<?xml version="1.0" encoding="US-ASCII"?>
<!--XBRL Document Created with Wdesk from Workiva-->
<!-- -->
<link:linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/AccruedExpensesAndOtherCurrentLiabilities" xlink:href="vlrx-20190331.xsd#AccruedExpensesAndOtherCurrentLiabilities" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/AccruedExpensesAndOtherCurrentLiabilitiesDetails" xlink:href="vlrx-20190331.xsd#AccruedExpensesAndOtherCurrentLiabilitiesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/AccruedExpensesAndOtherCurrentLiabilitiesTables" xlink:href="vlrx-20190331.xsd#AccruedExpensesAndOtherCurrentLiabilitiesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/BasisOfPresentationAndSignificantAccountingPolicies" xlink:href="vlrx-20190331.xsd#BasisOfPresentationAndSignificantAccountingPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/BasisOfPresentationAndSignificantAccountingPoliciesAdditionalInformationDetails" xlink:href="vlrx-20190331.xsd#BasisOfPresentationAndSignificantAccountingPoliciesAdditionalInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/BasisOfPresentationAndSignificantAccountingPoliciesPolicies" xlink:href="vlrx-20190331.xsd#BasisOfPresentationAndSignificantAccountingPoliciesPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/BasisOfPresentationAndSignificantAccountingPoliciesScheduleOfRecognitionOfAdoptionDetails" xlink:href="vlrx-20190331.xsd#BasisOfPresentationAndSignificantAccountingPoliciesScheduleOfRecognitionOfAdoptionDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/BasisOfPresentationAndSignificantAccountingPoliciesTables" xlink:href="vlrx-20190331.xsd#BasisOfPresentationAndSignificantAccountingPoliciesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/CommitmentsAndContingencies" xlink:href="vlrx-20190331.xsd#CommitmentsAndContingencies" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/CommitmentsAndContingenciesAdditionalInformationDetails" xlink:href="vlrx-20190331.xsd#CommitmentsAndContingenciesAdditionalInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/CommitmentsAndContingenciesOperatingLeaseAssetsAndLiabilitiesDetails" xlink:href="vlrx-20190331.xsd#CommitmentsAndContingenciesOperatingLeaseAssetsAndLiabilitiesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/CommitmentsAndContingenciesSummaryOfMinimumLeaseCommitmentsDetails" xlink:href="vlrx-20190331.xsd#CommitmentsAndContingenciesSummaryOfMinimumLeaseCommitmentsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/CommitmentsAndContingenciesSupplementalCashFlowsInformationDetails" xlink:href="vlrx-20190331.xsd#CommitmentsAndContingenciesSupplementalCashFlowsInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/CommitmentsAndContingenciesTables" xlink:href="vlrx-20190331.xsd#CommitmentsAndContingenciesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/CondensedConsolidatedBalanceSheetsUnaudited" xlink:href="vlrx-20190331.xsd#CondensedConsolidatedBalanceSheetsUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/CondensedConsolidatedBalanceSheetsUnauditedParenthetical" xlink:href="vlrx-20190331.xsd#CondensedConsolidatedBalanceSheetsUnauditedParenthetical" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/CondensedConsolidatedStatementsOfCashFlowsUnaudited" xlink:href="vlrx-20190331.xsd#CondensedConsolidatedStatementsOfCashFlowsUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/CondensedConsolidatedStatementsOfOperationsUnaudited" xlink:href="vlrx-20190331.xsd#CondensedConsolidatedStatementsOfOperationsUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/CondensedConsolidatedStatementsOfStockholdersEquityDeficitUnaudited" xlink:href="vlrx-20190331.xsd#CondensedConsolidatedStatementsOfStockholdersEquityDeficitUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/Debt" xlink:href="vlrx-20190331.xsd#Debt" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/DebtDebtOutstandingDetails" xlink:href="vlrx-20190331.xsd#DebtDebtOutstandingDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/DebtOtherNotePayableDetails" xlink:href="vlrx-20190331.xsd#DebtOtherNotePayableDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/DebtSeniorSecuredDebtDetails" xlink:href="vlrx-20190331.xsd#DebtSeniorSecuredDebtDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/DebtTables" xlink:href="vlrx-20190331.xsd#DebtTables" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/DocumentAndEntityInformation" xlink:href="vlrx-20190331.xsd#DocumentAndEntityInformation" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/FairValueMeasurements" xlink:href="vlrx-20190331.xsd#FairValueMeasurements" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/Inventory" xlink:href="vlrx-20190331.xsd#Inventory" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/InventoryAdditionalInformationDetails" xlink:href="vlrx-20190331.xsd#InventoryAdditionalInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/InventoryScheduleOfInventoryNetDetails" xlink:href="vlrx-20190331.xsd#InventoryScheduleOfInventoryNetDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/InventoryTables" xlink:href="vlrx-20190331.xsd#InventoryTables" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/NatureOfOperationsAndOrganization" xlink:href="vlrx-20190331.xsd#NatureOfOperationsAndOrganization" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/NetLossPerShare" xlink:href="vlrx-20190331.xsd#NetLossPerShare" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/NetLossPerShareAdditionalInformationDetails" xlink:href="vlrx-20190331.xsd#NetLossPerShareAdditionalInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/NetLossPerShareScheduleOfAntidilutiveOptionsNotIncludedInComputationOfWeightedAverageCommonSharesDetails" xlink:href="vlrx-20190331.xsd#NetLossPerShareScheduleOfAntidilutiveOptionsNotIncludedInComputationOfWeightedAverageCommonSharesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/NetLossPerShareTables" xlink:href="vlrx-20190331.xsd#NetLossPerShareTables" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/PropertyAndEquipment" xlink:href="vlrx-20190331.xsd#PropertyAndEquipment" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/PropertyAndEquipmentAdditionalInformationDetails" xlink:href="vlrx-20190331.xsd#PropertyAndEquipmentAdditionalInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/PropertyAndEquipmentScheduleOfPropertyAndEquipmentDetails" xlink:href="vlrx-20190331.xsd#PropertyAndEquipmentScheduleOfPropertyAndEquipmentDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/PropertyAndEquipmentTables" xlink:href="vlrx-20190331.xsd#PropertyAndEquipmentTables" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/RelatedPartyTransactions" xlink:href="vlrx-20190331.xsd#RelatedPartyTransactions" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/RelatedPartyTransactionsDetails" xlink:href="vlrx-20190331.xsd#RelatedPartyTransactionsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/RevenueFromContractWithCustomers" xlink:href="vlrx-20190331.xsd#RevenueFromContractWithCustomers" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/StockholdersEquityDeficit" xlink:href="vlrx-20190331.xsd#StockholdersEquityDeficit" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/StockholdersEquityDeficitEquityCompensationPlansDetails" xlink:href="vlrx-20190331.xsd#StockholdersEquityDeficitEquityCompensationPlansDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/StockholdersEquityDeficitNarrativeDetails" xlink:href="vlrx-20190331.xsd#StockholdersEquityDeficitNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/StockholdersEquityDeficitScheduleOfKeyAssumptionsDetails" xlink:href="vlrx-20190331.xsd#StockholdersEquityDeficitScheduleOfKeyAssumptionsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/StockholdersEquityDeficitScheduleOfStockOptionActivityDetails" xlink:href="vlrx-20190331.xsd#StockholdersEquityDeficitScheduleOfStockOptionActivityDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/StockholdersEquityDeficitStockOptionsDetails" xlink:href="vlrx-20190331.xsd#StockholdersEquityDeficitStockOptionsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/StockholdersEquityDeficitTables" xlink:href="vlrx-20190331.xsd#StockholdersEquityDeficitTables" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/SubsequentEvents" xlink:href="vlrx-20190331.xsd#SubsequentEvents" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/UncertaintiesLiquidityAndAbilityToContinueAsGoingConcern" xlink:href="vlrx-20190331.xsd#UncertaintiesLiquidityAndAbilityToContinueAsGoingConcern" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/UncertaintiesLiquidityAndAbilityToContinueAsGoingConcernDetails" xlink:href="vlrx-20190331.xsd#UncertaintiesLiquidityAndAbilityToContinueAsGoingConcernDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/Warrants" xlink:href="vlrx-20190331.xsd#Warrants" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/WarrantsAdditionalInformationDetails" xlink:href="vlrx-20190331.xsd#WarrantsAdditionalInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/WarrantsScheduleOfActivitiesOfWarrantsDetails" xlink:href="vlrx-20190331.xsd#WarrantsScheduleOfActivitiesOfWarrantsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://imetrix.edgar-online.com/role/WarrantsTables" xlink:href="vlrx-20190331.xsd#WarrantsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedNetLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedNetLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodEndLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodEndLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodStartLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodStartLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTerseLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTotalLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/netLabel" xlink:href="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd#netLabel" xlink:type="simple" />
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/AccruedExpensesAndOtherCurrentLiabilities" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PayablesAndAccrualsAbstract" xlink:label="loc_us-gaap_PayablesAndAccrualsAbstract_5D4F40F763F10F9471387B2001D4E96D" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentTextBlock" xlink:label="loc_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentTextBlock_776FF45541B88D68C9117B2001D4BEF1" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PayablesAndAccrualsAbstract_5D4F40F763F10F9471387B2001D4E96D" xlink:to="loc_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentTextBlock_776FF45541B88D68C9117B2001D4BEF1" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/AccruedExpensesAndOtherCurrentLiabilitiesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PayablesAndAccrualsAbstract" xlink:label="loc_us-gaap_PayablesAndAccrualsAbstract_E8525655ACA9103DCE8C8F3463480EE2" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredCompensationLiabilityCurrent" xlink:label="loc_us-gaap_DeferredCompensationLiabilityCurrent_DFCBEDC6505C594293FC8F346348EFC4" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PayablesAndAccrualsAbstract_E8525655ACA9103DCE8C8F3463480EE2" xlink:to="loc_us-gaap_DeferredCompensationLiabilityCurrent_DFCBEDC6505C594293FC8F346348EFC4" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_AccruedDistributionAgreementAndManagedCareCosts" xlink:label="loc_vlrx_AccruedDistributionAgreementAndManagedCareCosts_C99B41B6F9B2B828FA498F346349D51B" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PayablesAndAccrualsAbstract_E8525655ACA9103DCE8C8F3463480EE2" xlink:to="loc_vlrx_AccruedDistributionAgreementAndManagedCareCosts_C99B41B6F9B2B828FA498F346349D51B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccruedMarketingCostsCurrent" xlink:label="loc_us-gaap_AccruedMarketingCostsCurrent_0507A3745D4EBAAB06F48F3463491575" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PayablesAndAccrualsAbstract_E8525655ACA9103DCE8C8F3463480EE2" xlink:to="loc_us-gaap_AccruedMarketingCostsCurrent_0507A3745D4EBAAB06F48F3463491575" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SalesReturnProvision" xlink:label="loc_vlrx_SalesReturnProvision_F54747ABEFB23B383F958F3463496F26" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PayablesAndAccrualsAbstract_E8525655ACA9103DCE8C8F3463480EE2" xlink:to="loc_vlrx_SalesReturnProvision_F54747ABEFB23B383F958F3463496F26" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccruedProfessionalFeesCurrent" xlink:label="loc_us-gaap_AccruedProfessionalFeesCurrent_06683B7EC4B4E3ABC6E88F346349C2D1" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PayablesAndAccrualsAbstract_E8525655ACA9103DCE8C8F3463480EE2" xlink:to="loc_us-gaap_AccruedProfessionalFeesCurrent_06683B7EC4B4E3ABC6E88F346349C2D1" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_AccruedManufacturingCostsCurrent" xlink:label="loc_vlrx_AccruedManufacturingCostsCurrent_ED2A1BF7F56C22402DAF8F34634A888A" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PayablesAndAccrualsAbstract_E8525655ACA9103DCE8C8F3463480EE2" xlink:to="loc_vlrx_AccruedManufacturingCostsCurrent_ED2A1BF7F56C22402DAF8F34634A888A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherAccruedLiabilitiesCurrent" xlink:label="loc_us-gaap_OtherAccruedLiabilitiesCurrent_CA5D78F32BED003C51D38F34634A5119" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PayablesAndAccrualsAbstract_E8525655ACA9103DCE8C8F3463480EE2" xlink:to="loc_us-gaap_OtherAccruedLiabilitiesCurrent_CA5D78F32BED003C51D38F34634A5119" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccruedLiabilitiesAndOtherLiabilities" xlink:label="loc_us-gaap_AccruedLiabilitiesAndOtherLiabilities_61DAFFC086639F84146F8F34634A64AC" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PayablesAndAccrualsAbstract_E8525655ACA9103DCE8C8F3463480EE2" xlink:to="loc_us-gaap_AccruedLiabilitiesAndOtherLiabilities_61DAFFC086639F84146F8F34634A64AC" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/AccruedExpensesAndOtherCurrentLiabilitiesTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PayablesAndAccrualsAbstract" xlink:label="loc_us-gaap_PayablesAndAccrualsAbstract_C9FFBB975A5C475CDD007B2002C616D0" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfAccountsPayableAndAccruedLiabilitiesTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfAccountsPayableAndAccruedLiabilitiesTableTextBlock_1D54B0B868966687CA987B2002C66D81" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PayablesAndAccrualsAbstract_C9FFBB975A5C475CDD007B2002C616D0" xlink:to="loc_us-gaap_ScheduleOfAccountsPayableAndAccruedLiabilitiesTableTextBlock_1D54B0B868966687CA987B2002C66D81" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/BasisOfPresentationAndSignificantAccountingPolicies" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract_C07BCEDF5003C00BDAA37B20017184A9" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock" xlink:label="loc_us-gaap_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock_C6B7673C2CD2AC280C5A7B2001715E3E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_C07BCEDF5003C00BDAA37B20017184A9" xlink:to="loc_us-gaap_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock_C6B7673C2CD2AC280C5A7B2001715E3E" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/BasisOfPresentationAndSignificantAccountingPoliciesAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract_2A5472EC525AEF1193877B9D1A74F7BB" xlink:type="locator" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_NumberofLeasedBuildings" xlink:label="loc_vlrx_NumberofLeasedBuildings_75EA51D2CC6AC2ACCDBC7BB4B74F593C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_2A5472EC525AEF1193877B9D1A74F7BB" xlink:to="loc_vlrx_NumberofLeasedBuildings_75EA51D2CC6AC2ACCDBC7BB4B74F593C" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/BasisOfPresentationAndSignificantAccountingPoliciesPolicies" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract_4529426DCB67C222A0157ED5B50F17B5" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:label="loc_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_6B80206520234FDDE3247ED5B510023C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_4529426DCB67C222A0157ED5B50F17B5" xlink:to="loc_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_6B80206520234FDDE3247ED5B510023C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:label="loc_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_0DFBFFEBDF4CFBDFA5C67ED5B5101E91" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_4529426DCB67C222A0157ED5B50F17B5" xlink:to="loc_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_0DFBFFEBDF4CFBDFA5C67ED5B5101E91" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/BasisOfPresentationAndSignificantAccountingPoliciesScheduleOfRecognitionOfAdoptionDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract_FC32D2C56C7C41FAE8228F028A245617" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_3BD8BDF50CC18C1135DC8F028A26927A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_FC32D2C56C7C41FAE8228F028A245617" xlink:to="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_3BD8BDF50CC18C1135DC8F028A26927A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:label="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_DC72CC5946960F8B74D58F028A277657" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_3BD8BDF50CC18C1135DC8F028A26927A" xlink:to="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_DC72CC5946960F8B74D58F028A277657" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_F2B235705B68CC997F2E8F028A2843F4" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_DC72CC5946960F8B74D58F028A277657" xlink:to="loc_us-gaap_TypeOfAdoptionMember_F2B235705B68CC997F2E8F028A2843F4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingStandardsUpdate201602Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201602Member_62D1BC89F466986A95068F028A28EFC8" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_TypeOfAdoptionMember_F2B235705B68CC997F2E8F028A2843F4" xlink:to="loc_us-gaap_AccountingStandardsUpdate201602Member_62D1BC89F466986A95068F028A28EFC8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_28BAFAF66341BB776B038F028A2A6C7B" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_3BD8BDF50CC18C1135DC8F028A26927A" xlink:to="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_28BAFAF66341BB776B038F028A2A6C7B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset_7287F77F37CB633638B58F028A2ABF07" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_28BAFAF66341BB776B038F028A2A6C7B" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAsset_7287F77F37CB633638B58F028A2ABF07" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="loc_us-gaap_OperatingLeaseLiabilityCurrent_59BCF922474E5EDB9F8C8F028A2AD641" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_28BAFAF66341BB776B038F028A2A6C7B" xlink:to="loc_us-gaap_OperatingLeaseLiabilityCurrent_59BCF922474E5EDB9F8C8F028A2AD641" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:label="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_0417372460D60A5F90058F028A2B62CA" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_28BAFAF66341BB776B038F028A2A6C7B" xlink:to="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_0417372460D60A5F90058F028A2B62CA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalLeaseObligationsCurrent" xlink:label="loc_us-gaap_CapitalLeaseObligationsCurrent_DA6962FC7A55129EAD538F028A2B2FA8" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_28BAFAF66341BB776B038F028A2A6C7B" xlink:to="loc_us-gaap_CapitalLeaseObligationsCurrent_DA6962FC7A55129EAD538F028A2B2FA8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FinanceLeaseLiabilityCurrent" xlink:label="loc_us-gaap_FinanceLeaseLiabilityCurrent_F1FA8A8A70E0056F3B2B8F028A2BCFD8" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_28BAFAF66341BB776B038F028A2A6C7B" xlink:to="loc_us-gaap_FinanceLeaseLiabilityCurrent_F1FA8A8A70E0056F3B2B8F028A2BCFD8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredRentCredit" xlink:label="loc_us-gaap_DeferredRentCredit_4A5115425D03513DA5948F028A2B69D6" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_28BAFAF66341BB776B038F028A2A6C7B" xlink:to="loc_us-gaap_DeferredRentCredit_4A5115425D03513DA5948F028A2B69D6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalLeaseObligationsNoncurrent" xlink:label="loc_us-gaap_CapitalLeaseObligationsNoncurrent_623AB637C09E064108508F028A2B1176" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_28BAFAF66341BB776B038F028A2A6C7B" xlink:to="loc_us-gaap_CapitalLeaseObligationsNoncurrent_623AB637C09E064108508F028A2B1176" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FinanceLeaseLiabilityNoncurrent" xlink:label="loc_us-gaap_FinanceLeaseLiabilityNoncurrent_C9DCE08573B3CD86A5348F028A2B41C0" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_28BAFAF66341BB776B038F028A2A6C7B" xlink:to="loc_us-gaap_FinanceLeaseLiabilityNoncurrent_C9DCE08573B3CD86A5348F028A2B41C0" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/BasisOfPresentationAndSignificantAccountingPoliciesTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract_26EBA9C3929AFE8D0A5D5FC443FA43F6" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock" xlink:label="loc_us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock_C4E0772567346786FF555FC443FA0360" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_26EBA9C3929AFE8D0A5D5FC443FA43F6" xlink:to="loc_us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock_C4E0772567346786FF555FC443FA0360" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/CommitmentsAndContingencies" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_55958AC4F3406EDAB18C7B2003061409" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_F69104C8BAA9193700567B2003069C1C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_55958AC4F3406EDAB18C7B2003061409" xlink:to="loc_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_F69104C8BAA9193700567B2003069C1C" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/CommitmentsAndContingenciesAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_E926ACCB74A14277CE6F7B9D19C1DD26" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LeaseCost" xlink:label="loc_us-gaap_LeaseCost_55075507E64CE05DC8717B9D19C1598F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_E926ACCB74A14277CE6F7B9D19C1DD26" xlink:to="loc_us-gaap_LeaseCost_55075507E64CE05DC8717B9D19C1598F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LeaseAndRentalExpense" xlink:label="loc_us-gaap_LeaseAndRentalExpense_DF14E5E546AE9308231E7B9D19C29C99" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_E926ACCB74A14277CE6F7B9D19C1DD26" xlink:to="loc_us-gaap_LeaseAndRentalExpense_DF14E5E546AE9308231E7B9D19C29C99" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" xlink:label="loc_us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_5E0D6415CC0B8EF068FF7B9D19C26F51" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_E926ACCB74A14277CE6F7B9D19C1DD26" xlink:to="loc_us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_5E0D6415CC0B8EF068FF7B9D19C26F51" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1" xlink:label="loc_us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_CFCE5BFDEB4B0567BC4B7B9D19C2BD24" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_E926ACCB74A14277CE6F7B9D19C1DD26" xlink:to="loc_us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1_CFCE5BFDEB4B0567BC4B7B9D19C2BD24" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_FinanceLeaseNumberofLeases" xlink:label="loc_vlrx_FinanceLeaseNumberofLeases_1F1D1D596587BE0566B67B9D19C25884" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_E926ACCB74A14277CE6F7B9D19C1DD26" xlink:to="loc_vlrx_FinanceLeaseNumberofLeases_1F1D1D596587BE0566B67B9D19C25884" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FinanceLeaseRightOfUseAsset" xlink:label="loc_us-gaap_FinanceLeaseRightOfUseAsset_578BEFF8D5321224ABE87B9D19C23A6D" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_E926ACCB74A14277CE6F7B9D19C1DD26" xlink:to="loc_us-gaap_FinanceLeaseRightOfUseAsset_578BEFF8D5321224ABE87B9D19C23A6D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount" xlink:label="loc_us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount_30E4D3C5E3EAA447A2D87B9D19C2653A" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_E926ACCB74A14277CE6F7B9D19C1DD26" xlink:to="loc_us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount_30E4D3C5E3EAA447A2D87B9D19C2653A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalLeasedAssetsGross" xlink:label="loc_us-gaap_CapitalLeasedAssetsGross_CFC6281AC0BDFC46E05B7C05DEFBA64B" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_E926ACCB74A14277CE6F7B9D19C1DD26" xlink:to="loc_us-gaap_CapitalLeasedAssetsGross_CFC6281AC0BDFC46E05B7C05DEFBA64B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FinanceLeaseRightOfUseAssetAmortization" xlink:label="loc_us-gaap_FinanceLeaseRightOfUseAssetAmortization_65615AC8AD88D746540F7C0849A99A76" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_E926ACCB74A14277CE6F7B9D19C1DD26" xlink:to="loc_us-gaap_FinanceLeaseRightOfUseAssetAmortization_65615AC8AD88D746540F7C0849A99A76" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CommitmentsAndContingenciesTable" xlink:label="loc_vlrx_CommitmentsAndContingenciesTable_9873562E778CE95E1D5B7B9D19C35CD4" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_E926ACCB74A14277CE6F7B9D19C1DD26" xlink:to="loc_vlrx_CommitmentsAndContingenciesTable_9873562E778CE95E1D5B7B9D19C35CD4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherCommitmentsAxis" xlink:label="loc_us-gaap_OtherCommitmentsAxis_1673F33F3056747F14D77B9D19C30B96" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_CommitmentsAndContingenciesTable_9873562E778CE95E1D5B7B9D19C35CD4" xlink:to="loc_us-gaap_OtherCommitmentsAxis_1673F33F3056747F14D77B9D19C30B96" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherCommitmentsDomain" xlink:label="loc_us-gaap_OtherCommitmentsDomain_B83A981BBF1652FA8ECE7B9D19C3CE22" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OtherCommitmentsAxis_1673F33F3056747F14D77B9D19C30B96" xlink:to="loc_us-gaap_OtherCommitmentsDomain_B83A981BBF1652FA8ECE7B9D19C3CE22" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_IntegrationFeeMember" xlink:label="loc_vlrx_IntegrationFeeMember_7ACA86CC70DEADDF876F7B9D19C37BB0" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OtherCommitmentsDomain_B83A981BBF1652FA8ECE7B9D19C3CE22" xlink:to="loc_vlrx_IntegrationFeeMember_7ACA86CC70DEADDF876F7B9D19C37BB0" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_AnnualMaintenanceFeeMember" xlink:label="loc_vlrx_AnnualMaintenanceFeeMember_5B9F12E94C912AB07EB37B9D19C49C33" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OtherCommitmentsDomain_B83A981BBF1652FA8ECE7B9D19C3CE22" xlink:to="loc_vlrx_AnnualMaintenanceFeeMember_5B9F12E94C912AB07EB37B9D19C49C33" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaap_RelatedPartyTransactionAxis_7BEE780FB98602F5E7A07B9D19C439B8" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_CommitmentsAndContingenciesTable_9873562E778CE95E1D5B7B9D19C35CD4" xlink:to="loc_us-gaap_RelatedPartyTransactionAxis_7BEE780FB98602F5E7A07B9D19C439B8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_A9C9F679C984B07902D57B9D19C4DD32" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionAxis_7BEE780FB98602F5E7A07B9D19C439B8" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_A9C9F679C984B07902D57B9D19C4DD32" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_BioValveMember" xlink:label="loc_vlrx_BioValveMember_23466DE9B22410B19D1A7B9D19C4AC7E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_A9C9F679C984B07902D57B9D19C4DD32" xlink:to="loc_vlrx_BioValveMember_23466DE9B22410B19D1A7B9D19C4AC7E" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CommitmentsAndContingenciesLineItems" xlink:label="loc_vlrx_CommitmentsAndContingenciesLineItems_D02E93FA9F27183A20997B9D19C5523F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_CommitmentsAndContingenciesTable_9873562E778CE95E1D5B7B9D19C35CD4" xlink:to="loc_vlrx_CommitmentsAndContingenciesLineItems_D02E93FA9F27183A20997B9D19C5523F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherCommitment" xlink:label="loc_us-gaap_OtherCommitment_DD6353C86D8BE8BBD6587B9D19C5E6F2" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_CommitmentsAndContingenciesLineItems_D02E93FA9F27183A20997B9D19C5523F" xlink:to="loc_us-gaap_OtherCommitment_DD6353C86D8BE8BBD6587B9D19C5E6F2" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_OtherCommitmentTerm" xlink:label="loc_vlrx_OtherCommitmentTerm_D53EBCD6A527ADC28AA37B9D19C54ECC" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_CommitmentsAndContingenciesLineItems_D02E93FA9F27183A20997B9D19C5523F" xlink:to="loc_vlrx_OtherCommitmentTerm_D53EBCD6A527ADC28AA37B9D19C54ECC" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_LicensingPaymentPercentage" xlink:label="loc_vlrx_LicensingPaymentPercentage_D74E103679959DD3F3B27B9D19C5439E" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_CommitmentsAndContingenciesLineItems_D02E93FA9F27183A20997B9D19C5523F" xlink:to="loc_vlrx_LicensingPaymentPercentage_D74E103679959DD3F3B27B9D19C5439E" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_LicensingPaymentCertainCircumstancePercentage" xlink:label="loc_vlrx_LicensingPaymentCertainCircumstancePercentage_6F511ADC11535BABAD967B9D19C5389B" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_CommitmentsAndContingenciesLineItems_D02E93FA9F27183A20997B9D19C5523F" xlink:to="loc_vlrx_LicensingPaymentCertainCircumstancePercentage_6F511ADC11535BABAD967B9D19C5389B" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_AmountsOwedUnderLicensingAgreement" xlink:label="loc_vlrx_AmountsOwedUnderLicensingAgreement_9D8D1F33C3604AAF67F57B9D19C50501" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_CommitmentsAndContingenciesLineItems_D02E93FA9F27183A20997B9D19C5523F" xlink:to="loc_vlrx_AmountsOwedUnderLicensingAgreement_9D8D1F33C3604AAF67F57B9D19C50501" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/CommitmentsAndContingenciesOperatingLeaseAssetsAndLiabilitiesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_EF04F45D7F8F310FE85D7ED5B47A80AF" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset_EF75281478114313E5617ED5B47A12EA" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_EF04F45D7F8F310FE85D7ED5B47A80AF" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAsset_EF75281478114313E5617ED5B47A12EA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeaseLiability" xlink:label="loc_us-gaap_OperatingLeaseLiability_5F85B31B9236B25E5E7F7ED5B47A861D" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_EF04F45D7F8F310FE85D7ED5B47A80AF" xlink:to="loc_us-gaap_OperatingLeaseLiability_5F85B31B9236B25E5E7F7ED5B47A861D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1A45836ECDCD70DA23997ED5B47BA827" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_EF04F45D7F8F310FE85D7ED5B47A80AF" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1A45836ECDCD70DA23997ED5B47BA827" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/CommitmentsAndContingenciesSummaryOfMinimumLeaseCommitmentsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_05F78613B7C35F832CCF8F3462AA6EA3" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_E44786844127F38F05E38F3462AAE608" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_05F78613B7C35F832CCF8F3462AA6EA3" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_E44786844127F38F05E38F3462AAE608" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_96030467836E4838760E8F3462ABB504" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_05F78613B7C35F832CCF8F3462AA6EA3" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_96030467836E4838760E8F3462ABB504" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_7E89FF31CC6D4B172E0C8F3462ABF3C2" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_05F78613B7C35F832CCF8F3462AA6EA3" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_7E89FF31CC6D4B172E0C8F3462ABF3C2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_68D6499F64F6401293518F3462ABD461" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_05F78613B7C35F832CCF8F3462AA6EA3" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_68D6499F64F6401293518F3462ABD461" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_F83865693ABC5447F2328F3462AB452B" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_05F78613B7C35F832CCF8F3462AA6EA3" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_F83865693ABC5447F2328F3462AB452B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_B01D7270C30DEA1F32D48F3462AB7915" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_05F78613B7C35F832CCF8F3462AA6EA3" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_B01D7270C30DEA1F32D48F3462AB7915" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_50C8F94ED721168B96758F3462AC7AFC" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_05F78613B7C35F832CCF8F3462AA6EA3" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_50C8F94ED721168B96758F3462AC7AFC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_4E569179B867C03225578F3462ACED98" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_05F78613B7C35F832CCF8F3462AA6EA3" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_4E569179B867C03225578F3462ACED98" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeaseLiability" xlink:label="loc_us-gaap_OperatingLeaseLiability_435D8151C4EDC76256E98F3462AC8CD4" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_05F78613B7C35F832CCF8F3462AA6EA3" xlink:to="loc_us-gaap_OperatingLeaseLiability_435D8151C4EDC76256E98F3462AC8CD4" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/CommitmentsAndContingenciesSupplementalCashFlowsInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_DCC7B2F806FD7A522D788F045213CB36" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeasePayments" xlink:label="loc_us-gaap_OperatingLeasePayments_7EE5CB3AA0BD3C0EB1458F04521330DF" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_DCC7B2F806FD7A522D788F045213CB36" xlink:to="loc_us-gaap_OperatingLeasePayments_7EE5CB3AA0BD3C0EB1458F04521330DF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FinanceLeasePrincipalPayments" xlink:label="loc_us-gaap_FinanceLeasePrincipalPayments_6FA8EEABC6F4EB75E0FD8F1DB1F307BC" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_DCC7B2F806FD7A522D788F045213CB36" xlink:to="loc_us-gaap_FinanceLeasePrincipalPayments_6FA8EEABC6F4EB75E0FD8F1DB1F307BC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FinanceLeaseInterestPaymentOnLiability" xlink:label="loc_us-gaap_FinanceLeaseInterestPaymentOnLiability_8E26D7A495418796A62B8F0452132D95" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_DCC7B2F806FD7A522D788F045213CB36" xlink:to="loc_us-gaap_FinanceLeaseInterestPaymentOnLiability_8E26D7A495418796A62B8F0452132D95" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_LeasePayments" xlink:label="loc_vlrx_LeasePayments_B1055A34798F8CA23A6E8F045214111C" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_DCC7B2F806FD7A522D788F045213CB36" xlink:to="loc_vlrx_LeasePayments_B1055A34798F8CA23A6E8F045214111C" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/CommitmentsAndContingenciesTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_9666D09235D0BF347D465FC38A687586" xlink:type="locator" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_AssetsAndLiabilitiesLesseeTableTextBlock" xlink:label="loc_vlrx_AssetsAndLiabilitiesLesseeTableTextBlock_49DF1F604D6F13A359435FC3BDE3C73E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_9666D09235D0BF347D465FC38A687586" xlink:to="loc_vlrx_AssetsAndLiabilitiesLesseeTableTextBlock_49DF1F604D6F13A359435FC3BDE3C73E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LeaseCostTableTextBlock" xlink:label="loc_us-gaap_LeaseCostTableTextBlock_8CE8B99E3D592BAABC995FCB23CE9454" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_9666D09235D0BF347D465FC38A687586" xlink:to="loc_us-gaap_LeaseCostTableTextBlock_8CE8B99E3D592BAABC995FCB23CE9454" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_299FE9E6DEE151D1419E5FD2AC13590F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_9666D09235D0BF347D465FC38A687586" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_299FE9E6DEE151D1419E5FD2AC13590F" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/CondensedConsolidatedBalanceSheetsUnaudited" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementOfFinancialPositionAbstract" xlink:label="loc_us-gaap_StatementOfFinancialPositionAbstract_F328DCCE3F131CC03FD57F16A83FECEA" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AssetsAbstract" xlink:label="loc_us-gaap_AssetsAbstract_6218FBC3EF1A4083DECF7F16A83FD60B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_F328DCCE3F131CC03FD57F16A83FECEA" xlink:to="loc_us-gaap_AssetsAbstract_6218FBC3EF1A4083DECF7F16A83FD60B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AssetsCurrentAbstract" xlink:label="loc_us-gaap_AssetsCurrentAbstract_C74443BD8956B1F4E47D7F16A83F10A4" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsAbstract_6218FBC3EF1A4083DECF7F16A83FD60B" xlink:to="loc_us-gaap_AssetsCurrentAbstract_C74443BD8956B1F4E47D7F16A83F10A4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_7A72983B128C967694037F16A840B23A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsCurrentAbstract_C74443BD8956B1F4E47D7F16A83F10A4" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_7A72983B128C967694037F16A840B23A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_32141A4055781573B3137F16A840E2FF" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsCurrentAbstract_C74443BD8956B1F4E47D7F16A83F10A4" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_32141A4055781573B3137F16A840E2FF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaap_InventoryNet_0D2F1D5ED86A2F5E501A7F16A8402AF1" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsCurrentAbstract_C74443BD8956B1F4E47D7F16A83F10A4" xlink:to="loc_us-gaap_InventoryNet_0D2F1D5ED86A2F5E501A7F16A8402AF1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_7F05DF22581D8FF5462B7F16A8405F07" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsCurrentAbstract_C74443BD8956B1F4E47D7F16A83F10A4" xlink:to="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_7F05DF22581D8FF5462B7F16A8405F07" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaap_AssetsCurrent_8D88D26E2B3B4DB140AF7F16A8406223" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsCurrentAbstract_C74443BD8956B1F4E47D7F16A83F10A4" xlink:to="loc_us-gaap_AssetsCurrent_8D88D26E2B3B4DB140AF7F16A8406223" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_E0BB1CD486D2510791187F16A8411616" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsAbstract_6218FBC3EF1A4083DECF7F16A83FD60B" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_E0BB1CD486D2510791187F16A8411616" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset_81C40B36A7E1B13121D47F16A841E155" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsAbstract_6218FBC3EF1A4083DECF7F16A83FD60B" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAsset_81C40B36A7E1B13121D47F16A841E155" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_62D3577D89A89191389E7F16A841EC2F" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsAbstract_6218FBC3EF1A4083DECF7F16A83FD60B" xlink:to="loc_us-gaap_OtherAssetsNoncurrent_62D3577D89A89191389E7F16A841EC2F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Assets" xlink:label="loc_us-gaap_Assets_0979773283E86C3D0B217F16A841FBF8" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AssetsAbstract_6218FBC3EF1A4083DECF7F16A83FD60B" xlink:to="loc_us-gaap_Assets_0979773283E86C3D0B217F16A841FBF8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_F25F5C4BCF7A8E085B867F16A841AA3D" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_F328DCCE3F131CC03FD57F16A83FECEA" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_F25F5C4BCF7A8E085B867F16A841AA3D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="loc_us-gaap_LiabilitiesCurrentAbstract_1A7BF6516AE38044CA297F16A841183A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_F25F5C4BCF7A8E085B867F16A841AA3D" xlink:to="loc_us-gaap_LiabilitiesCurrentAbstract_1A7BF6516AE38044CA297F16A841183A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaap_AccountsPayableCurrent_2DD7214C52B7C845DD577F16A842F3F4" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_1A7BF6516AE38044CA297F16A841183A" xlink:to="loc_us-gaap_AccountsPayableCurrent_2DD7214C52B7C845DD577F16A842F3F4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccruedLiabilitiesAndOtherLiabilities" xlink:label="loc_us-gaap_AccruedLiabilitiesAndOtherLiabilities_28F831F2901ED9BC7FC57F16A842288B" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_1A7BF6516AE38044CA297F16A841183A" xlink:to="loc_us-gaap_AccruedLiabilitiesAndOtherLiabilities_28F831F2901ED9BC7FC57F16A842288B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="loc_us-gaap_OperatingLeaseLiabilityCurrent_D37727E536FF906006367F16A842C7F1" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_1A7BF6516AE38044CA297F16A841183A" xlink:to="loc_us-gaap_OperatingLeaseLiabilityCurrent_D37727E536FF906006367F16A842C7F1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FinanceLeaseLiabilityCurrent" xlink:label="loc_us-gaap_FinanceLeaseLiabilityCurrent_01710DB36626922941BE7F16A8424F3E" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_1A7BF6516AE38044CA297F16A841183A" xlink:to="loc_us-gaap_FinanceLeaseLiabilityCurrent_01710DB36626922941BE7F16A8424F3E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalLeaseObligationsCurrent" xlink:label="loc_us-gaap_CapitalLeaseObligationsCurrent_190C71C2E4D054D7EEFB7F2A98AE154A" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_1A7BF6516AE38044CA297F16A841183A" xlink:to="loc_us-gaap_CapitalLeaseObligationsCurrent_190C71C2E4D054D7EEFB7F2A98AE154A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaap_LiabilitiesCurrent_51DAC097826720D3611F7F16A842E6A1" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_1A7BF6516AE38044CA297F16A841183A" xlink:to="loc_us-gaap_LiabilitiesCurrent_51DAC097826720D3611F7F16A842E6A1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DueToRelatedPartiesNoncurrent" xlink:label="loc_us-gaap_DueToRelatedPartiesNoncurrent_5F9713239D0CA82EB4BB7F16A8433800" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_F25F5C4BCF7A8E085B867F16A841AA3D" xlink:to="loc_us-gaap_DueToRelatedPartiesNoncurrent_5F9713239D0CA82EB4BB7F16A8433800" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:label="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_4BF8450B5A791B8592397F16A8435350" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_F25F5C4BCF7A8E085B867F16A841AA3D" xlink:to="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_4BF8450B5A791B8592397F16A8435350" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredRentCreditNoncurrent" xlink:label="loc_us-gaap_DeferredRentCreditNoncurrent_F0C3FFD7C839EC81511E7F16A843937B" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_F25F5C4BCF7A8E085B867F16A841AA3D" xlink:to="loc_us-gaap_DeferredRentCreditNoncurrent_F0C3FFD7C839EC81511E7F16A843937B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_7554716F14BD39B8A2707F16A8437745" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_F25F5C4BCF7A8E085B867F16A841AA3D" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrent_7554716F14BD39B8A2707F16A8437745" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaap_Liabilities_B73CC9477213A22508507F16A8430E26" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_F25F5C4BCF7A8E085B867F16A841AA3D" xlink:to="loc_us-gaap_Liabilities_B73CC9477213A22508507F16A8430E26" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommitmentsAndContingencies" xlink:label="loc_us-gaap_CommitmentsAndContingencies_9AA216908C25A827C1DF7F16A843EA77" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_F25F5C4BCF7A8E085B867F16A841AA3D" xlink:to="loc_us-gaap_CommitmentsAndContingencies_9AA216908C25A827C1DF7F16A843EA77" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityAbstract" xlink:label="loc_us-gaap_StockholdersEquityAbstract_4DFD2066AFFFE65358D07F16A8449736" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_F25F5C4BCF7A8E085B867F16A841AA3D" xlink:to="loc_us-gaap_StockholdersEquityAbstract_4DFD2066AFFFE65358D07F16A8449736" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockValue" xlink:label="loc_us-gaap_PreferredStockValue_7F6B514BB552F8EE920B7F16A84438A2" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityAbstract_4DFD2066AFFFE65358D07F16A8449736" xlink:to="loc_us-gaap_PreferredStockValue_7F6B514BB552F8EE920B7F16A84438A2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaap_CommonStockValue_0A5D7F7C0B31367666347F16A844B282" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityAbstract_4DFD2066AFFFE65358D07F16A8449736" xlink:to="loc_us-gaap_CommonStockValue_0A5D7F7C0B31367666347F16A844B282" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="loc_us-gaap_AdditionalPaidInCapital_0A9964C8DE48DB56DE897F16A8441109" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityAbstract_4DFD2066AFFFE65358D07F16A8449736" xlink:to="loc_us-gaap_AdditionalPaidInCapital_0A9964C8DE48DB56DE897F16A8441109" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_B4AEFA471C4EA57E855B7F16A84415A2" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityAbstract_4DFD2066AFFFE65358D07F16A8449736" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_B4AEFA471C4EA57E855B7F16A84415A2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TreasuryStockValue" xlink:label="loc_us-gaap_TreasuryStockValue_1E3FA0E9C0A16D4B56727F16A8445E51" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityAbstract_4DFD2066AFFFE65358D07F16A8449736" xlink:to="loc_us-gaap_TreasuryStockValue_1E3FA0E9C0A16D4B56727F16A8445E51" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity_84FDFD1EDCBCF7EE04587F16A84472BD" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StockholdersEquityAbstract_4DFD2066AFFFE65358D07F16A8449736" xlink:to="loc_us-gaap_StockholdersEquity_84FDFD1EDCBCF7EE04587F16A84472BD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_67FD2E6D2D80DA10EF677F16A84503D0" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_F25F5C4BCF7A8E085B867F16A841AA3D" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquity_67FD2E6D2D80DA10EF677F16A84503D0" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/CondensedConsolidatedBalanceSheetsUnauditedParenthetical" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementOfFinancialPositionAbstract" xlink:label="loc_us-gaap_StatementOfFinancialPositionAbstract_551F2F181D8BFF9C26C07B2002A515A4" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_PreferredStockParOrStatedValuePerShare_56826E404EF817C0869B7B2002A503E7" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_551F2F181D8BFF9C26C07B2002A515A4" xlink:to="loc_us-gaap_PreferredStockParOrStatedValuePerShare_56826E404EF817C0869B7B2002A503E7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_68DDC1AA4064EB2A9E757B2002B5DDB7" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_551F2F181D8BFF9C26C07B2002A515A4" xlink:to="loc_us-gaap_PreferredStockSharesAuthorized_68DDC1AA4064EB2A9E757B2002B5DDB7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockSharesIssued" xlink:label="loc_us-gaap_PreferredStockSharesIssued_0B8A578AAD4A74DE5EDE7B2002B59ACC" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_551F2F181D8BFF9C26C07B2002A515A4" xlink:to="loc_us-gaap_PreferredStockSharesIssued_0B8A578AAD4A74DE5EDE7B2002B59ACC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockSharesOutstanding" xlink:label="loc_us-gaap_PreferredStockSharesOutstanding_8EB052D015C20A1C01E17B2002B548E5" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_551F2F181D8BFF9C26C07B2002A515A4" xlink:to="loc_us-gaap_PreferredStockSharesOutstanding_8EB052D015C20A1C01E17B2002B548E5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockLiquidationPreferenceValue" xlink:label="loc_us-gaap_PreferredStockLiquidationPreferenceValue_AB546B043A5997ECD8497B2002B6AB08" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_551F2F181D8BFF9C26C07B2002A515A4" xlink:to="loc_us-gaap_PreferredStockLiquidationPreferenceValue_AB546B043A5997ECD8497B2002B6AB08" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_B31BFCFB333E96278FD37B2002B60A79" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_551F2F181D8BFF9C26C07B2002A515A4" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_B31BFCFB333E96278FD37B2002B60A79" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_09B6C631F7570B83C95A7B2002B62683" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_551F2F181D8BFF9C26C07B2002A515A4" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_09B6C631F7570B83C95A7B2002B62683" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaap_CommonStockSharesIssued_BED8470D3D8B7C399FAC7B2002B6CBC3" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_551F2F181D8BFF9C26C07B2002A515A4" xlink:to="loc_us-gaap_CommonStockSharesIssued_BED8470D3D8B7C399FAC7B2002B6CBC3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_1E5AFDA3DD9A12248A707B2002B6D96E" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_551F2F181D8BFF9C26C07B2002A515A4" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_1E5AFDA3DD9A12248A707B2002B6D96E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TreasuryStockShares" xlink:label="loc_us-gaap_TreasuryStockShares_22A5AC9CC2BECE3A525F7B2002B6A786" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_551F2F181D8BFF9C26C07B2002A515A4" xlink:to="loc_us-gaap_TreasuryStockShares_22A5AC9CC2BECE3A525F7B2002B6A786" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/CondensedConsolidatedStatementsOfCashFlowsUnaudited" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementOfCashFlowsAbstract" xlink:label="loc_us-gaap_StatementOfCashFlowsAbstract_A09912D3F3A50FA4F08D98566C24ACD1" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_6B07EE9800A31EAB818E98566C2424ED" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_A09912D3F3A50FA4F08D98566C24ACD1" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_6B07EE9800A31EAB818E98566C2424ED" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_B011E4F4B91DC5DFAC7798566C250FE1" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_6B07EE9800A31EAB818E98566C2424ED" xlink:to="loc_us-gaap_NetIncomeLoss_B011E4F4B91DC5DFAC7798566C250FE1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_6ADA5D474AF52B878CF898566C264B28" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_6B07EE9800A31EAB818E98566C2424ED" xlink:to="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_6ADA5D474AF52B878CF898566C264B28" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_563E504B348C6460B34598566C26934D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_6ADA5D474AF52B878CF898566C264B28" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_563E504B348C6460B34598566C26934D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="loc_us-gaap_AmortizationOfFinancingCosts_FBFFE64C739D1B759E4598566C278B19" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_6ADA5D474AF52B878CF898566C264B28" xlink:to="loc_us-gaap_AmortizationOfFinancingCosts_FBFFE64C739D1B759E4598566C278B19" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaidInKindInterest" xlink:label="loc_us-gaap_PaidInKindInterest_F157163F8F3680DAA7DF98566C27346D" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_6ADA5D474AF52B878CF898566C264B28" xlink:to="loc_us-gaap_PaidInKindInterest_F157163F8F3680DAA7DF98566C27346D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:label="loc_us-gaap_ShareBasedCompensation_1A457BFF208C89E4AC9698566C2744B8" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_6ADA5D474AF52B878CF898566C264B28" xlink:to="loc_us-gaap_ShareBasedCompensation_1A457BFF208C89E4AC9698566C2744B8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryWriteDown" xlink:label="loc_us-gaap_InventoryWriteDown_B90E009B9CD2638FCCD398566C28A9C0" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_6ADA5D474AF52B878CF898566C264B28" xlink:to="loc_us-gaap_InventoryWriteDown_B90E009B9CD2638FCCD398566C28A9C0" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_IncreaseDecreaseinSalesReturns" xlink:label="loc_vlrx_IncreaseDecreaseinSalesReturns_F1FC9B0742EC05856A3498566C29450A" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_6ADA5D474AF52B878CF898566C264B28" xlink:to="loc_vlrx_IncreaseDecreaseinSalesReturns_F1FC9B0742EC05856A3498566C29450A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7257E56C2032EFAF08F198566C295F7C" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_6B07EE9800A31EAB818E98566C2424ED" xlink:to="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7257E56C2032EFAF08F198566C295F7C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_9487CE7A52921CEDC68098566C298703" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7257E56C2032EFAF08F198566C295F7C" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_9487CE7A52921CEDC68098566C298703" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInInventories" xlink:label="loc_us-gaap_IncreaseDecreaseInInventories_A6A46E1D81F85F174FDE98566C2ABEEE" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7257E56C2032EFAF08F198566C295F7C" xlink:to="loc_us-gaap_IncreaseDecreaseInInventories_A6A46E1D81F85F174FDE98566C2ABEEE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_F9E10932757DE1F0DA4598566C2A8BD8" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7257E56C2032EFAF08F198566C295F7C" xlink:to="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_F9E10932757DE1F0DA4598566C2A8BD8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInOtherOperatingAssets" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets_2A8516050DE875BC4FB198566C2A3304" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7257E56C2032EFAF08F198566C295F7C" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets_2A8516050DE875BC4FB198566C2A3304" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsPayable" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayable_7379435547B24396CC4D98566C2B249D" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7257E56C2032EFAF08F198566C295F7C" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsPayable_7379435547B24396CC4D98566C2B249D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInAccruedLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInAccruedLiabilities_D9C5D99ABF36A7361D4598566C2C1E1E" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7257E56C2032EFAF08F198566C295F7C" xlink:to="loc_us-gaap_IncreaseDecreaseInAccruedLiabilities_D9C5D99ABF36A7361D4598566C2C1E1E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInDeferredLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInDeferredLiabilities_A1BF8564D513AFEE5F7B98566C2D1BC2" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7257E56C2032EFAF08F198566C295F7C" xlink:to="loc_us-gaap_IncreaseDecreaseInDeferredLiabilities_A1BF8564D513AFEE5F7B98566C2D1BC2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_D4DE7D7263BEAFD777DF98566C2E0119" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_6B07EE9800A31EAB818E98566C2424ED" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_D4DE7D7263BEAFD777DF98566C2E0119" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_ED421E9E3530F22B3F7D98566C2E030C" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_A09912D3F3A50FA4F08D98566C24ACD1" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_ED421E9E3530F22B3F7D98566C2E030C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_243FBB698588A7F761ED98566C2ECB25" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_ED421E9E3530F22B3F7D98566C2E030C" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_243FBB698588A7F761ED98566C2ECB25" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_FBAC6E9887A9B211D70498566C2FEDB9" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_ED421E9E3530F22B3F7D98566C2E030C" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_FBAC6E9887A9B211D70498566C2FEDB9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_44374BAD8C8A66BB570398566C2FBA85" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_A09912D3F3A50FA4F08D98566C24ACD1" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_44374BAD8C8A66BB570398566C2FBA85" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RepaymentsOfLongTermCapitalLeaseObligations" xlink:label="loc_us-gaap_RepaymentsOfLongTermCapitalLeaseObligations_E2C74860F0726F8274B398566C31C080" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_44374BAD8C8A66BB570398566C2FBA85" xlink:to="loc_us-gaap_RepaymentsOfLongTermCapitalLeaseObligations_E2C74860F0726F8274B398566C31C080" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_4BF716CA37C53105907798566C31D30F" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_44374BAD8C8A66BB570398566C2FBA85" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_4BF716CA37C53105907798566C31D30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans_735848F7B45CDA6086EF98566C312F81" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_44374BAD8C8A66BB570398566C2FBA85" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans_735848F7B45CDA6086EF98566C312F81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_E6B18217715DCA8BB69598566C31B197" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_44374BAD8C8A66BB570398566C2FBA85" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_E6B18217715DCA8BB69598566C31B197" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_C7AF19351667D717CF2F98566C32E1E5" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_A09912D3F3A50FA4F08D98566C24ACD1" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_C7AF19351667D717CF2F98566C32E1E5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_FBFACD1347E4F779C99C98566C33555B" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_A09912D3F3A50FA4F08D98566C24ACD1" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_FBFACD1347E4F779C99C98566C33555B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_F22A25EBD39E389362EB98566C33E274" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_A09912D3F3A50FA4F08D98566C24ACD1" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_F22A25EBD39E389362EB98566C33E274" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" xlink:label="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_5A672BBA6FB8B752B67E98566C34429E" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_A09912D3F3A50FA4F08D98566C24ACD1" xlink:to="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_5A672BBA6FB8B752B67E98566C34429E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability" xlink:label="loc_us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_350D3EF927CD7215561198566C34BCFC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_5A672BBA6FB8B752B67E98566C34429E" xlink:to="loc_us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_350D3EF927CD7215561198566C34BCFC" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_OperatingLeaseLiabilityinExchangeforRightofUseAsset" xlink:label="loc_vlrx_OperatingLeaseLiabilityinExchangeforRightofUseAsset_309FD03DF0F374B34F1298566C35F871" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_5A672BBA6FB8B752B67E98566C34429E" xlink:to="loc_vlrx_OperatingLeaseLiabilityinExchangeforRightofUseAsset_309FD03DF0F374B34F1298566C35F871" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_NoncashDeferredRent" xlink:label="loc_vlrx_NoncashDeferredRent_3D719F36F836D1ABDB7D98566C35D90F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_5A672BBA6FB8B752B67E98566C34429E" xlink:to="loc_vlrx_NoncashDeferredRent_3D719F36F836D1ABDB7D98566C35D90F" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ContractwithCustomerLiabilityReduction" xlink:label="loc_vlrx_ContractwithCustomerLiabilityReduction_8D5A8779D1AFB6BA12CB98566C35658C" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_5A672BBA6FB8B752B67E98566C34429E" xlink:to="loc_vlrx_ContractwithCustomerLiabilityReduction_8D5A8779D1AFB6BA12CB98566C35658C" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SalesReturnProvisionInitialApplication" xlink:label="loc_vlrx_SalesReturnProvisionInitialApplication_BA814B688499946FB3D098566C360D87" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_5A672BBA6FB8B752B67E98566C34429E" xlink:to="loc_vlrx_SalesReturnProvisionInitialApplication_BA814B688499946FB3D098566C360D87" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_NoncashDeferredCostofGoodsSoldReduction" xlink:label="loc_vlrx_NoncashDeferredCostofGoodsSoldReduction_431600B02DC5E1A6A29798566C379E13" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_5A672BBA6FB8B752B67E98566C34429E" xlink:to="loc_vlrx_NoncashDeferredCostofGoodsSoldReduction_431600B02DC5E1A6A29798566C379E13" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_AccruedDistributionFeesandManagedCareCosts" xlink:label="loc_vlrx_AccruedDistributionFeesandManagedCareCosts_6D15A85593A26EF8E35998566C374884" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_5A672BBA6FB8B752B67E98566C34429E" xlink:to="loc_vlrx_AccruedDistributionFeesandManagedCareCosts_6D15A85593A26EF8E35998566C374884" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalLeaseObligationsIncurred" xlink:label="loc_us-gaap_CapitalLeaseObligationsIncurred_18C34488F6A6A9F9D9C598566C37552F" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_5A672BBA6FB8B752B67E98566C34429E" xlink:to="loc_us-gaap_CapitalLeaseObligationsIncurred_18C34488F6A6A9F9D9C598566C37552F" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_OfferingCostsIncurredButNotYetPaid" xlink:label="loc_vlrx_OfferingCostsIncurredButNotYetPaid_EB3F131D46C23A1C55C598566C387AAE" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_5A672BBA6FB8B752B67E98566C34429E" xlink:to="loc_vlrx_OfferingCostsIncurredButNotYetPaid_EB3F131D46C23A1C55C598566C387AAE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherNoncashInvestingAndFinancingItemsAbstract" xlink:label="loc_us-gaap_OtherNoncashInvestingAndFinancingItemsAbstract_82CB56C42F7D46AF9C3898566C38C2DB" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_A09912D3F3A50FA4F08D98566C24ACD1" xlink:to="loc_us-gaap_OtherNoncashInvestingAndFinancingItemsAbstract_82CB56C42F7D46AF9C3898566C38C2DB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalExpendituresIncurredButNotYetPaid" xlink:label="loc_us-gaap_CapitalExpendituresIncurredButNotYetPaid_7414E055146A2DC46D0198566C39BDB8" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OtherNoncashInvestingAndFinancingItemsAbstract_82CB56C42F7D46AF9C3898566C38C2DB" xlink:to="loc_us-gaap_CapitalExpendituresIncurredButNotYetPaid_7414E055146A2DC46D0198566C39BDB8" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/CondensedConsolidatedStatementsOfOperationsUnaudited" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:label="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_154CFAFAAB22B14F66857B1FFF245DA9" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_AA9C6AAD174D94DB04BC7B1FFF241782" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_154CFAFAAB22B14F66857B1FFF245DA9" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_AA9C6AAD174D94DB04BC7B1FFF241782" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CostOfGoodsAndServicesSold" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_A1766A9246C7C05819B47B1FFF24223A" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_154CFAFAAB22B14F66857B1FFF245DA9" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_A1766A9246C7C05819B47B1FFF24223A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GrossProfit" xlink:label="loc_us-gaap_GrossProfit_A298788FDCC675D26D277B1FFF330136" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_154CFAFAAB22B14F66857B1FFF245DA9" xlink:to="loc_us-gaap_GrossProfit_A298788FDCC675D26D277B1FFF330136" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingExpensesAbstract" xlink:label="loc_us-gaap_OperatingExpensesAbstract_E037873B7E3D5FB26D027B1FFF33A794" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_154CFAFAAB22B14F66857B1FFF245DA9" xlink:to="loc_us-gaap_OperatingExpensesAbstract_E037873B7E3D5FB26D027B1FFF33A794" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense_CA7F0EA968F9AD02FA857B1FFF335CA8" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingExpensesAbstract_E037873B7E3D5FB26D027B1FFF33A794" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpense_CA7F0EA968F9AD02FA857B1FFF335CA8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SellingGeneralAndAdministrativeExpense" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense_AA05503F69F5266FD55A7B1FFF33AF3C" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingExpensesAbstract_E037873B7E3D5FB26D027B1FFF33A794" xlink:to="loc_us-gaap_SellingGeneralAndAdministrativeExpense_AA05503F69F5266FD55A7B1FFF33AF3C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingExpenses" xlink:label="loc_us-gaap_OperatingExpenses_13972E1FA7E2EB8759BA7B1FFF332EF7" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingExpensesAbstract_E037873B7E3D5FB26D027B1FFF33A794" xlink:to="loc_us-gaap_OperatingExpenses_13972E1FA7E2EB8759BA7B1FFF332EF7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_78D9DCF75AD3BF77762D7B1FFF33FF25" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OperatingExpensesAbstract_E037873B7E3D5FB26D027B1FFF33A794" xlink:to="loc_us-gaap_OperatingIncomeLoss_78D9DCF75AD3BF77762D7B1FFF33FF25" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NonoperatingIncomeExpenseAbstract" xlink:label="loc_us-gaap_NonoperatingIncomeExpenseAbstract_8537B14FCE4D1D450AC17B1FFF3319F9" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_154CFAFAAB22B14F66857B1FFF245DA9" xlink:to="loc_us-gaap_NonoperatingIncomeExpenseAbstract_8537B14FCE4D1D450AC17B1FFF3319F9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense_F629B5EFC22DA99F5B887B1FFF3370DE" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_8537B14FCE4D1D450AC17B1FFF3319F9" xlink:to="loc_us-gaap_InterestExpense_F629B5EFC22DA99F5B887B1FFF3370DE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherNonoperatingExpense" xlink:label="loc_us-gaap_OtherNonoperatingExpense_4E0A90F1EB07EF31EDEE7B1FFF33E81B" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_8537B14FCE4D1D450AC17B1FFF3319F9" xlink:to="loc_us-gaap_OtherNonoperatingExpense_4E0A90F1EB07EF31EDEE7B1FFF33E81B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherNonoperatingIncome" xlink:label="loc_us-gaap_OtherNonoperatingIncome_59CBF4B20EB219F0EF267B1FFF33B9F9" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_8537B14FCE4D1D450AC17B1FFF3319F9" xlink:to="loc_us-gaap_OtherNonoperatingIncome_59CBF4B20EB219F0EF267B1FFF33B9F9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NonoperatingIncomeExpense" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_4BCF6A36AFEF3B7C9D947B1FFF332E50" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_8537B14FCE4D1D450AC17B1FFF3319F9" xlink:to="loc_us-gaap_NonoperatingIncomeExpense_4BCF6A36AFEF3B7C9D947B1FFF332E50" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_E7EB3D4DAB59CFD191287B1FFF330EE1" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_154CFAFAAB22B14F66857B1FFF245DA9" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_E7EB3D4DAB59CFD191287B1FFF330EE1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_636D7868127C68E41DBE7B1FFF3367E8" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_154CFAFAAB22B14F66857B1FFF245DA9" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_636D7868127C68E41DBE7B1FFF3367E8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_928764C9C72413049A407B1FFF331D4B" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_154CFAFAAB22B14F66857B1FFF245DA9" xlink:to="loc_us-gaap_NetIncomeLoss_928764C9C72413049A407B1FFF331D4B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockDividendsIncomeStatementImpact" xlink:label="loc_us-gaap_PreferredStockDividendsIncomeStatementImpact_47CBD4F4A31DE3E4586C7B1FFF33CAE0" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_154CFAFAAB22B14F66857B1FFF245DA9" xlink:to="loc_us-gaap_PreferredStockDividendsIncomeStatementImpact_47CBD4F4A31DE3E4586C7B1FFF33CAE0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic" xlink:label="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_1CAA6E84868E8726C59F7B1FFF33FEB3" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_154CFAFAAB22B14F66857B1FFF245DA9" xlink:to="loc_us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_1CAA6E84868E8726C59F7B1FFF33FEB3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareBasicAndDiluted" xlink:label="loc_us-gaap_EarningsPerShareBasicAndDiluted_C9300D78CF85B2D8206B7B1FFF33E12C" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_154CFAFAAB22B14F66857B1FFF245DA9" xlink:to="loc_us-gaap_EarningsPerShareBasicAndDiluted_C9300D78CF85B2D8206B7B1FFF33E12C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:label="loc_us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted_39808EE6AC0BA2FAAE287B1FFF3337A7" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_154CFAFAAB22B14F66857B1FFF245DA9" xlink:to="loc_us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted_39808EE6AC0BA2FAAE287B1FFF3337A7" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/CondensedConsolidatedStatementsOfStockholdersEquityDeficitUnaudited" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementOfStockholdersEquityAbstract" xlink:label="loc_us-gaap_StatementOfStockholdersEquityAbstract_1736A13D4BED264E4B2B9DDFFEC66B9C" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_820F53194A795941FDAB9DDFFEC60F09" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementOfStockholdersEquityAbstract_1736A13D4BED264E4B2B9DDFFEC66B9C" xlink:to="loc_us-gaap_StatementTable_820F53194A795941FDAB9DDFFEC60F09" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_35F346B63A9B50FBA0799DDFFEC64577" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementTable_820F53194A795941FDAB9DDFFEC60F09" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_35F346B63A9B50FBA0799DDFFEC64577" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_7D0920AA61520908142D9DDFFEC6C4D0" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_35F346B63A9B50FBA0799DDFFEC64577" xlink:to="loc_us-gaap_EquityComponentDomain_7D0920AA61520908142D9DDFFEC6C4D0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockMember" xlink:label="loc_us-gaap_PreferredStockMember_DBFD82E07234F2D8A1CF9DDFFEC641AE" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_7D0920AA61520908142D9DDFFEC6C4D0" xlink:to="loc_us-gaap_PreferredStockMember_DBFD82E07234F2D8A1CF9DDFFEC641AE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember_EA810872F3DEFC00F3609DDFFEC7DFE1" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_7D0920AA61520908142D9DDFFEC6C4D0" xlink:to="loc_us-gaap_CommonStockMember_EA810872F3DEFC00F3609DDFFEC7DFE1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TreasuryStockMember" xlink:label="loc_us-gaap_TreasuryStockMember_5BBC32703DB1DAA48AD49DDFFEC76945" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_7D0920AA61520908142D9DDFFEC6C4D0" xlink:to="loc_us-gaap_TreasuryStockMember_5BBC32703DB1DAA48AD49DDFFEC76945" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_1DB3471BD96AC2FC897A9DDFFEC76E18" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_7D0920AA61520908142D9DDFFEC6C4D0" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_1DB3471BD96AC2FC897A9DDFFEC76E18" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember_6C1F71F6C50A130819159DDFFEC7D3E2" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_7D0920AA61520908142D9DDFFEC6C4D0" xlink:to="loc_us-gaap_RetainedEarningsMember_6C1F71F6C50A130819159DDFFEC7D3E2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_DAD88A07264D64A77AC39DDFFEC7AE75" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementTable_820F53194A795941FDAB9DDFFEC60F09" xlink:to="loc_us-gaap_StatementLineItems_DAD88A07264D64A77AC39DDFFEC7AE75" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementLineItems_DAD88A07264D64A77AC39DDFFEC7AE75" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity_915FA9EDC3A83E823ABB9DDFFEC87F1B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:to="loc_us-gaap_StockholdersEquity_915FA9EDC3A83E823ABB9DDFFEC87F1B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharesOutstanding" xlink:label="loc_us-gaap_SharesOutstanding_C189B8F73DEC760AFA409DDFFEC8B494" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:to="loc_us-gaap_SharesOutstanding_C189B8F73DEC760AFA409DDFFEC8B494" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption" xlink:label="loc_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_8EB9B18EDD158DD2DE829DDFFEC82D2A" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:to="loc_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_8EB9B18EDD158DD2DE829DDFFEC82D2A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_E4694E0799ACFBE319059DDFFEC9F036" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_E4694E0799ACFBE319059DDFFEC9F036" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_ABEB867626ADF7181BE99DDFFEC9EFE5" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_ABEB867626ADF7181BE99DDFFEC9EFE5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_E260A02C5CDEFF4648C79DDFFEC924E0" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_E260A02C5CDEFF4648C79DDFFEC924E0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockAndWarrantsIssuedDuringPeriodValuePreferredStockAndWarrants" xlink:label="loc_us-gaap_StockAndWarrantsIssuedDuringPeriodValuePreferredStockAndWarrants_F1C98F795081269148889DDFFEC901F8" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:to="loc_us-gaap_StockAndWarrantsIssuedDuringPeriodValuePreferredStockAndWarrants_F1C98F795081269148889DDFFEC901F8" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_StockIssuedDuringPeriodSharesExerciseOfWarrants" xlink:label="loc_vlrx_StockIssuedDuringPeriodSharesExerciseOfWarrants_9FEFB5C27E09A5F14C989DDFFEC90521" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:to="loc_vlrx_StockIssuedDuringPeriodSharesExerciseOfWarrants_9FEFB5C27E09A5F14C989DDFFEC90521" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross_72AFC3D23FAFE7184FF99DDFFEC9ECB1" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross_72AFC3D23FAFE7184FF99DDFFEC9ECB1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_9D1BBAE38EFF6B60F8B19DDFFECA6D86" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_9D1BBAE38EFF6B60F8B19DDFFECA6D86" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_12CDABFCE9F1550B77519DDFFECA9517" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_12CDABFCE9F1550B77519DDFFECA9517" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_7213987BA294A3120DDD9DDFFECABE38" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:to="loc_us-gaap_NetIncomeLoss_7213987BA294A3120DDD9DDFFECABE38" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity_9CB2AB17170E1901C6A89DDFFECA69D5" xlink:type="locator" />
    <link:presentationArc order="13" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:to="loc_us-gaap_StockholdersEquity_9CB2AB17170E1901C6A89DDFFECA69D5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharesOutstanding" xlink:label="loc_us-gaap_SharesOutstanding_4464E45F4F0DA2D0A5AC9DDFFECAE99B" xlink:type="locator" />
    <link:presentationArc order="14" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_D43E3FF3978E5B18F5949DDFFEC8CEFC" xlink:to="loc_us-gaap_SharesOutstanding_4464E45F4F0DA2D0A5AC9DDFFECAE99B" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/Debt" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtDisclosureAbstract" xlink:label="loc_us-gaap_DebtDisclosureAbstract_36996CFFA1D3A4CBDE5F7B2001C5546B" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtDisclosureTextBlock" xlink:label="loc_us-gaap_DebtDisclosureTextBlock_1C116AFB8E54CB096A337B2001C5B3D0" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_36996CFFA1D3A4CBDE5F7B2001C5546B" xlink:to="loc_us-gaap_DebtDisclosureTextBlock_1C116AFB8E54CB096A337B2001C5B3D0" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/DebtDebtOutstandingDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtDisclosureAbstract" xlink:label="loc_us-gaap_DebtDisclosureAbstract_F0E3DCFCB5FBCD7BB6317B9D1A455F7D" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_2177678E1056BEAB4A4E7B9D1A450B04" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_F0E3DCFCB5FBCD7BB6317B9D1A455F7D" xlink:to="loc_us-gaap_DebtInstrumentTable_2177678E1056BEAB4A4E7B9D1A450B04" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_21F4C4B86AEB9C1033827B9D1A463595" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_2177678E1056BEAB4A4E7B9D1A450B04" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_21F4C4B86AEB9C1033827B9D1A463595" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_C2D2C93C1884EA9DCBD87B9D1A4641C6" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_21F4C4B86AEB9C1033827B9D1A463595" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_C2D2C93C1884EA9DCBD87B9D1A4641C6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeniorNotesMember" xlink:label="loc_us-gaap_SeniorNotesMember_50E164A17EE8E181868A7B9D1A46E302" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_C2D2C93C1884EA9DCBD87B9D1A4641C6" xlink:to="loc_us-gaap_SeniorNotesMember_50E164A17EE8E181868A7B9D1A46E302" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentInKindPIKNoteMember" xlink:label="loc_us-gaap_PaymentInKindPIKNoteMember_A484AD27392A9929F9EE7B9D1A4732D5" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_C2D2C93C1884EA9DCBD87B9D1A4641C6" xlink:to="loc_us-gaap_PaymentInKindPIKNoteMember_A484AD27392A9929F9EE7B9D1A4732D5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NotesPayableOtherPayablesMember" xlink:label="loc_us-gaap_NotesPayableOtherPayablesMember_196C4D968B57BA0F9E3D7B9D1A477BBE" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_C2D2C93C1884EA9DCBD87B9D1A4641C6" xlink:to="loc_us-gaap_NotesPayableOtherPayablesMember_196C4D968B57BA0F9E3D7B9D1A477BBE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_4BA03C62DBF12F0E07327B9D1A4782BA" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_2177678E1056BEAB4A4E7B9D1A450B04" xlink:to="loc_us-gaap_DebtInstrumentLineItems_4BA03C62DBF12F0E07327B9D1A4782BA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SecuredDebt" xlink:label="loc_us-gaap_SecuredDebt_4A85572FDE24412805FA7B9D1A47752B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_4BA03C62DBF12F0E07327B9D1A4782BA" xlink:to="loc_us-gaap_SecuredDebt_4A85572FDE24412805FA7B9D1A47752B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredFinanceCostsNet" xlink:label="loc_us-gaap_DeferredFinanceCostsNet_BC81FB5AE4A015BB676E7B9D1A473EA4" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_4BA03C62DBF12F0E07327B9D1A4782BA" xlink:to="loc_us-gaap_DeferredFinanceCostsNet_BC81FB5AE4A015BB676E7B9D1A473EA4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherNotesPayable" xlink:label="loc_us-gaap_OtherNotesPayable_1E542823DFB57071A4497B9D1A474F40" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_4BA03C62DBF12F0E07327B9D1A4782BA" xlink:to="loc_us-gaap_OtherNotesPayable_1E542823DFB57071A4497B9D1A474F40" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaap_LongTermDebt_A525CDBB7C374C6F0E5D7B9D1A48AE1E" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_4BA03C62DBF12F0E07327B9D1A4782BA" xlink:to="loc_us-gaap_LongTermDebt_A525CDBB7C374C6F0E5D7B9D1A48AE1E" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/DebtOtherNotePayableDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtDisclosureAbstract" xlink:label="loc_us-gaap_DebtDisclosureAbstract_B99C226BC736BEB37B9A7B9D1A2719DD" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_1F82F4A651E988A3D9EB7B9D1A27F410" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_B99C226BC736BEB37B9A7B9D1A2719DD" xlink:to="loc_us-gaap_DebtInstrumentTable_1F82F4A651E988A3D9EB7B9D1A27F410" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaap_CreditFacilityAxis_F0190E9CAE48C30935DB7BCE2904DEF6" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_1F82F4A651E988A3D9EB7B9D1A27F410" xlink:to="loc_us-gaap_CreditFacilityAxis_F0190E9CAE48C30935DB7BCE2904DEF6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_3FD32A4FF430EAFDB74A7BCE2906C7CE" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CreditFacilityAxis_F0190E9CAE48C30935DB7BCE2904DEF6" xlink:to="loc_us-gaap_CreditFacilityDomain_3FD32A4FF430EAFDB74A7BCE2906C7CE" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CapitalRoyaltyPartnersTermLoanMember" xlink:label="loc_vlrx_CapitalRoyaltyPartnersTermLoanMember_844323F8F86029D1840A7BCE2E2E9E6D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CreditFacilityDomain_3FD32A4FF430EAFDB74A7BCE2906C7CE" xlink:to="loc_vlrx_CapitalRoyaltyPartnersTermLoanMember_844323F8F86029D1840A7BCE2E2E9E6D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringPlanAxis" xlink:label="loc_us-gaap_RestructuringPlanAxis_D3E57DC74D59C4ECEBEE7B9D1A28BD1B" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_1F82F4A651E988A3D9EB7B9D1A27F410" xlink:to="loc_us-gaap_RestructuringPlanAxis_D3E57DC74D59C4ECEBEE7B9D1A28BD1B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringPlanDomain" xlink:label="loc_us-gaap_RestructuringPlanDomain_22DD8FD34DF8C6BA63D77B9D1A286ADA" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RestructuringPlanAxis_D3E57DC74D59C4ECEBEE7B9D1A28BD1B" xlink:to="loc_us-gaap_RestructuringPlanDomain_22DD8FD34DF8C6BA63D77B9D1A286ADA" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_RestructuredDebtMember" xlink:label="loc_vlrx_RestructuredDebtMember_8E615ED738FE0F0766077B9D1A28B763" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RestructuringPlanDomain_22DD8FD34DF8C6BA63D77B9D1A286ADA" xlink:to="loc_vlrx_RestructuredDebtMember_8E615ED738FE0F0766077B9D1A28B763" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_508A019E08446FA59C577B9D1A28A12C" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_1F82F4A651E988A3D9EB7B9D1A27F410" xlink:to="loc_us-gaap_DebtInstrumentAxis_508A019E08446FA59C577B9D1A28A12C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_9C1873901F40F08FA7E27B9D1A28B083" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentAxis_508A019E08446FA59C577B9D1A28A12C" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_9C1873901F40F08FA7E27B9D1A28B083" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_WcasCapitalPartnersIvLpMember" xlink:label="loc_vlrx_WcasCapitalPartnersIvLpMember_D546DA2D59D89B0B68A37B9D1A29F87D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_9C1873901F40F08FA7E27B9D1A28B083" xlink:to="loc_vlrx_WcasCapitalPartnersIvLpMember_D546DA2D59D89B0B68A37B9D1A29F87D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_4BCADEF6CEC290DBC79F7B9D1A29F7E1" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_1F82F4A651E988A3D9EB7B9D1A27F410" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_4BCADEF6CEC290DBC79F7B9D1A29F7E1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_192E2460B28F63A92AF07B9D1A2990CD" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_4BCADEF6CEC290DBC79F7B9D1A29F7E1" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_192E2460B28F63A92AF07B9D1A2990CD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NotesPayableOtherPayablesMember" xlink:label="loc_us-gaap_NotesPayableOtherPayablesMember_CA97FDD82A39EA7816937B9D1A2AA6E6" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_192E2460B28F63A92AF07B9D1A2990CD" xlink:to="loc_us-gaap_NotesPayableOtherPayablesMember_CA97FDD82A39EA7816937B9D1A2AA6E6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeniorSubordinatedNotesMember" xlink:label="loc_us-gaap_SeniorSubordinatedNotesMember_0B2F5DC005156C2897B37B9D1A2A34F0" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_192E2460B28F63A92AF07B9D1A2990CD" xlink:to="loc_us-gaap_SeniorSubordinatedNotesMember_0B2F5DC005156C2897B37B9D1A2A34F0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SecuredDebtMember" xlink:label="loc_us-gaap_SecuredDebtMember_EDD495BC9C90E1560EA87B9D1A2ABCFF" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_192E2460B28F63A92AF07B9D1A2990CD" xlink:to="loc_us-gaap_SecuredDebtMember_EDD495BC9C90E1560EA87B9D1A2ABCFF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentInKindPIKNoteMember" xlink:label="loc_us-gaap_PaymentInKindPIKNoteMember_A971540C8FDA5F5E79C77BCE329C66D8" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_192E2460B28F63A92AF07B9D1A2990CD" xlink:to="loc_us-gaap_PaymentInKindPIKNoteMember_A971540C8FDA5F5E79C77BCE329C66D8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaap_RelatedPartyTransactionAxis_8924A3DAF717B9F1FDDD7B9D1A2A58A0" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_1F82F4A651E988A3D9EB7B9D1A27F410" xlink:to="loc_us-gaap_RelatedPartyTransactionAxis_8924A3DAF717B9F1FDDD7B9D1A2A58A0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_DE7AC3CB80FE3222DC2D7B9D1A2A71FC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionAxis_8924A3DAF717B9F1FDDD7B9D1A2A58A0" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_DE7AC3CB80FE3222DC2D7B9D1A2A71FC" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember" xlink:label="loc_vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember_83745E8588BBD2E8BA437BCE30884F39" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_DE7AC3CB80FE3222DC2D7B9D1A2A71FC" xlink:to="loc_vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember_83745E8588BBD2E8BA437BCE30884F39" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DebtConversionCapitalRoyaltyPartnersMember" xlink:label="loc_vlrx_DebtConversionCapitalRoyaltyPartnersMember_181396A790BF8C32BF057BCE2FF95AD5" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember_83745E8588BBD2E8BA437BCE30884F39" xlink:to="loc_vlrx_DebtConversionCapitalRoyaltyPartnersMember_181396A790BF8C32BF057BCE2FF95AD5" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DebtConversionWCASMember" xlink:label="loc_vlrx_DebtConversionWCASMember_ACA16808C35DE1E2C59F7B9D1A2B9E54" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember_83745E8588BBD2E8BA437BCE30884F39" xlink:to="loc_vlrx_DebtConversionWCASMember_ACA16808C35DE1E2C59F7B9D1A2B9E54" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaap_StatementClassOfStockAxis_AB6EDD9A371DD826C79A7B9D1A2B12A2" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_1F82F4A651E988A3D9EB7B9D1A27F410" xlink:to="loc_us-gaap_StatementClassOfStockAxis_AB6EDD9A371DD826C79A7B9D1A2B12A2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_5C4D33E7E54AB3E7D2EF7B9D1A2B07C8" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementClassOfStockAxis_AB6EDD9A371DD826C79A7B9D1A2B12A2" xlink:to="loc_us-gaap_ClassOfStockDomain_5C4D33E7E54AB3E7D2EF7B9D1A2B07C8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeriesAPreferredStockMember" xlink:label="loc_us-gaap_SeriesAPreferredStockMember_807D5CA100CFDD5FDF497B9D1A2BC401" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockDomain_5C4D33E7E54AB3E7D2EF7B9D1A2B07C8" xlink:to="loc_us-gaap_SeriesAPreferredStockMember_807D5CA100CFDD5FDF497B9D1A2BC401" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_6F06FE9518CA7049D6D67B9D1A2C1696" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_1F82F4A651E988A3D9EB7B9D1A27F410" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_6F06FE9518CA7049D6D67B9D1A2C1696" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_1DE91F94B8206D7829EF7B9D1A2CFA42" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_6F06FE9518CA7049D6D67B9D1A2C1696" xlink:to="loc_us-gaap_EquityComponentDomain_1DE91F94B8206D7829EF7B9D1A2CFA42" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockMember" xlink:label="loc_us-gaap_PreferredStockMember_DE07F4461EEB19A6FBDA7B9D1A2CBB0B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_1DE91F94B8206D7829EF7B9D1A2CFA42" xlink:to="loc_us-gaap_PreferredStockMember_DE07F4461EEB19A6FBDA7B9D1A2CBB0B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_23A0523647061E3F39067B9D1A2C67F8" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_1F82F4A651E988A3D9EB7B9D1A27F410" xlink:to="loc_us-gaap_DebtInstrumentLineItems_23A0523647061E3F39067B9D1A2C67F8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentFaceAmount" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_A2FB051598077F4B07997B9D1A2DF369" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_23A0523647061E3F39067B9D1A2C67F8" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_A2FB051598077F4B07997B9D1A2DF369" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_5516CC08A9FAA69A38037B9D1A2D6EB1" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_23A0523647061E3F39067B9D1A2C67F8" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_5516CC08A9FAA69A38037B9D1A2D6EB1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentPeriodicPaymentInterest" xlink:label="loc_us-gaap_DebtInstrumentPeriodicPaymentInterest_82D6DB44E581BF7A792B7B9D1A2DCF78" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_23A0523647061E3F39067B9D1A2C67F8" xlink:to="loc_us-gaap_DebtInstrumentPeriodicPaymentInterest_82D6DB44E581BF7A792B7B9D1A2DCF78" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtConversionOriginalDebtAmount1" xlink:label="loc_us-gaap_DebtConversionOriginalDebtAmount1_E1B8AC0EF49083348A157B9D1A2DAF16" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_23A0523647061E3F39067B9D1A2C67F8" xlink:to="loc_us-gaap_DebtConversionOriginalDebtAmount1_E1B8AC0EF49083348A157B9D1A2DAF16" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentConvertibleConversionPrice1" xlink:label="loc_us-gaap_DebtInstrumentConvertibleConversionPrice1_0EF25038126FEF970EB87B9D1A2D1CD8" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_23A0523647061E3F39067B9D1A2C67F8" xlink:to="loc_us-gaap_DebtInstrumentConvertibleConversionPrice1_0EF25038126FEF970EB87B9D1A2D1CD8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtConversionConvertedInstrumentSharesIssued1" xlink:label="loc_us-gaap_DebtConversionConvertedInstrumentSharesIssued1_50BCF5C6E06E6AB000FD7B9D1A2D1856" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_23A0523647061E3F39067B9D1A2C67F8" xlink:to="loc_us-gaap_DebtConversionConvertedInstrumentSharesIssued1_50BCF5C6E06E6AB000FD7B9D1A2D1856" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaidInKindInterest" xlink:label="loc_us-gaap_PaidInKindInterest_8B50360B18B9B20B01B57BCE286602CF" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_23A0523647061E3F39067B9D1A2C67F8" xlink:to="loc_us-gaap_PaidInKindInterest_8B50360B18B9B20B01B57BCE286602CF" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/DebtSeniorSecuredDebtDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtDisclosureAbstract" xlink:label="loc_us-gaap_DebtDisclosureAbstract_E68E6D58E4FC24D734007B9D1A366821" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_E5C052A0285E1C5260E37B9D1A367080" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_E68E6D58E4FC24D734007B9D1A366821" xlink:to="loc_us-gaap_DebtInstrumentTable_E5C052A0285E1C5260E37B9D1A367080" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_E6C1F9E2D6E6D09318B07B9D1A37DA43" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_E5C052A0285E1C5260E37B9D1A367080" xlink:to="loc_us-gaap_DebtInstrumentAxis_E6C1F9E2D6E6D09318B07B9D1A37DA43" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_4B52D301DE758AA3BAEC7B9D1A374D07" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentAxis_E6C1F9E2D6E6D09318B07B9D1A37DA43" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_4B52D301DE758AA3BAEC7B9D1A374D07" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CapitalRoyaltyPartnersTermLoanMember" xlink:label="loc_vlrx_CapitalRoyaltyPartnersTermLoanMember_54368FF8E52C1B3269317B9D1A370AC2" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4B52D301DE758AA3BAEC7B9D1A374D07" xlink:to="loc_vlrx_CapitalRoyaltyPartnersTermLoanMember_54368FF8E52C1B3269317B9D1A370AC2" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_WcasCapitalPartnersIvLpMember" xlink:label="loc_vlrx_WcasCapitalPartnersIvLpMember_7B8AF44358AE917AB1B67B9D1A370038" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_4B52D301DE758AA3BAEC7B9D1A374D07" xlink:to="loc_vlrx_WcasCapitalPartnersIvLpMember_7B8AF44358AE917AB1B67B9D1A370038" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaap_CreditFacilityAxis_0127F8646BF1D90821DA7B9D1A380F15" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_E5C052A0285E1C5260E37B9D1A367080" xlink:to="loc_us-gaap_CreditFacilityAxis_0127F8646BF1D90821DA7B9D1A380F15" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_18DBCEC5198739DEEA037B9D1A386607" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CreditFacilityAxis_0127F8646BF1D90821DA7B9D1A380F15" xlink:to="loc_us-gaap_CreditFacilityDomain_18DBCEC5198739DEEA037B9D1A386607" xlink:type="arc" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_CreditFacilityDomain_18DBCEC5198739DEEA037B9D1A386607" xlink:to="loc_vlrx_CapitalRoyaltyPartnersTermLoanMember_54368FF8E52C1B3269317B9D1A370AC2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_7DAAB8C030AFA2A73A2B7B9D1A3874AF" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_E5C052A0285E1C5260E37B9D1A367080" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_7DAAB8C030AFA2A73A2B7B9D1A3874AF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_CB14F32CB744FE0800A37B9D1A38FF0C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_7DAAB8C030AFA2A73A2B7B9D1A3874AF" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_CB14F32CB744FE0800A37B9D1A38FF0C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentInKindPIKNoteMember" xlink:label="loc_us-gaap_PaymentInKindPIKNoteMember_1875675A7BA6A84996F37B9D1A39270A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_CB14F32CB744FE0800A37B9D1A38FF0C" xlink:to="loc_us-gaap_PaymentInKindPIKNoteMember_1875675A7BA6A84996F37B9D1A39270A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SecuredDebtMember" xlink:label="loc_us-gaap_SecuredDebtMember_7C403C9DF10C538577367B9D1A39365F" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_CB14F32CB744FE0800A37B9D1A38FF0C" xlink:to="loc_us-gaap_SecuredDebtMember_7C403C9DF10C538577367B9D1A39365F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NotesPayableOtherPayablesMember" xlink:label="loc_us-gaap_NotesPayableOtherPayablesMember_586A3D4EBA8D67E491297B9D1A39D05C" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_CB14F32CB744FE0800A37B9D1A38FF0C" xlink:to="loc_us-gaap_NotesPayableOtherPayablesMember_586A3D4EBA8D67E491297B9D1A39D05C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeniorSubordinatedNotesMember" xlink:label="loc_us-gaap_SeniorSubordinatedNotesMember_621008A3F4D1E09416F67B9D1A39D2A9" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_CB14F32CB744FE0800A37B9D1A38FF0C" xlink:to="loc_us-gaap_SeniorSubordinatedNotesMember_621008A3F4D1E09416F67B9D1A39D2A9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringPlanAxis" xlink:label="loc_us-gaap_RestructuringPlanAxis_3D0742D6910814D6EDAD7B9D1A398B94" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_E5C052A0285E1C5260E37B9D1A367080" xlink:to="loc_us-gaap_RestructuringPlanAxis_3D0742D6910814D6EDAD7B9D1A398B94" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringPlanDomain" xlink:label="loc_us-gaap_RestructuringPlanDomain_75D0452FD3AF657135D07B9D1A3A8195" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RestructuringPlanAxis_3D0742D6910814D6EDAD7B9D1A398B94" xlink:to="loc_us-gaap_RestructuringPlanDomain_75D0452FD3AF657135D07B9D1A3A8195" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_RestructuredDebtMember" xlink:label="loc_vlrx_RestructuredDebtMember_7E3F3EA9B48AF9C27C2B7B9D1A3A14AE" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RestructuringPlanDomain_75D0452FD3AF657135D07B9D1A3A8195" xlink:to="loc_vlrx_RestructuredDebtMember_7E3F3EA9B48AF9C27C2B7B9D1A3A14AE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaap_RelatedPartyTransactionAxis_D4E8EECB616AA99EB0677B9D1A3AD410" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_E5C052A0285E1C5260E37B9D1A367080" xlink:to="loc_us-gaap_RelatedPartyTransactionAxis_D4E8EECB616AA99EB0677B9D1A3AD410" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_C4D6285EAD087EDCE3667B9D1A3AA0BC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionAxis_D4E8EECB616AA99EB0677B9D1A3AD410" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_C4D6285EAD087EDCE3667B9D1A3AA0BC" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember" xlink:label="loc_vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember_23C868BDD225538EE4F87B9D1A3B2A20" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_C4D6285EAD087EDCE3667B9D1A3AA0BC" xlink:to="loc_vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember_23C868BDD225538EE4F87B9D1A3B2A20" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DebtConversionCapitalRoyaltyPartnersMember" xlink:label="loc_vlrx_DebtConversionCapitalRoyaltyPartnersMember_8B23C50F1C80C0B6422D7B9D1A3BB905" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember_23C868BDD225538EE4F87B9D1A3B2A20" xlink:to="loc_vlrx_DebtConversionCapitalRoyaltyPartnersMember_8B23C50F1C80C0B6422D7B9D1A3BB905" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DebtConversionWCASMember" xlink:label="loc_vlrx_DebtConversionWCASMember_A56F2E7ED5C627AF89F07B9D1A3B4A29" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_C4D6285EAD087EDCE3667B9D1A3AA0BC" xlink:to="loc_vlrx_DebtConversionWCASMember_A56F2E7ED5C627AF89F07B9D1A3B4A29" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaap_StatementClassOfStockAxis_D70430890DB3CD23B6EF7B9D1A3B1154" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_E5C052A0285E1C5260E37B9D1A367080" xlink:to="loc_us-gaap_StatementClassOfStockAxis_D70430890DB3CD23B6EF7B9D1A3B1154" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_C4FBEA718ABCF97A02457B9D1A3CF991" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementClassOfStockAxis_D70430890DB3CD23B6EF7B9D1A3B1154" xlink:to="loc_us-gaap_ClassOfStockDomain_C4FBEA718ABCF97A02457B9D1A3CF991" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeriesAPreferredStockMember" xlink:label="loc_us-gaap_SeriesAPreferredStockMember_53F0776F72A44D6100DA7B9D1A3C7148" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockDomain_C4FBEA718ABCF97A02457B9D1A3CF991" xlink:to="loc_us-gaap_SeriesAPreferredStockMember_53F0776F72A44D6100DA7B9D1A3C7148" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_8C8382FCFEB389E3B8317B9D1A3CF0DF" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_E5C052A0285E1C5260E37B9D1A367080" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_8C8382FCFEB389E3B8317B9D1A3CF0DF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_FB8107A60A708D03AF837B9D1A3CAD17" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_8C8382FCFEB389E3B8317B9D1A3CF0DF" xlink:to="loc_us-gaap_EquityComponentDomain_FB8107A60A708D03AF837B9D1A3CAD17" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockMember" xlink:label="loc_us-gaap_PreferredStockMember_50CC698EF35D112F65497B9D1A3C5FDB" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_FB8107A60A708D03AF837B9D1A3CAD17" xlink:to="loc_us-gaap_PreferredStockMember_50CC698EF35D112F65497B9D1A3C5FDB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_5CCA2682B37644D8C0427B9D1A3D1AF4" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentTable_E5C052A0285E1C5260E37B9D1A367080" xlink:to="loc_us-gaap_DebtInstrumentLineItems_5CCA2682B37644D8C0427B9D1A3D1AF4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_65257551E7AC83236ABE7B9D1A3D2F57" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5CCA2682B37644D8C0427B9D1A3D1AF4" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_65257551E7AC83236ABE7B9D1A3D2F57" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentTerm" xlink:label="loc_us-gaap_DebtInstrumentTerm_23FA32F7EB2BA399212E7B9D1A3D7275" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5CCA2682B37644D8C0427B9D1A3D1AF4" xlink:to="loc_us-gaap_DebtInstrumentTerm_23FA32F7EB2BA399212E7B9D1A3D7275" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_D4DB00A5625EFC442A137B9D1A3D79E5" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5CCA2682B37644D8C0427B9D1A3D1AF4" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_D4DB00A5625EFC442A137B9D1A3D79E5" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DebtInstrumentCovenantCashandCashEquivalents" xlink:label="loc_vlrx_DebtInstrumentCovenantCashandCashEquivalents_9DB4608DC9E274893AAE7B9D1A3D5E8A" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5CCA2682B37644D8C0427B9D1A3D1AF4" xlink:to="loc_vlrx_DebtInstrumentCovenantCashandCashEquivalents_9DB4608DC9E274893AAE7B9D1A3D5E8A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_882162357F7DD9885C1A7B9D1A3E2E5C" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5CCA2682B37644D8C0427B9D1A3D1AF4" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_882162357F7DD9885C1A7B9D1A3E2E5C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestrictedCash" xlink:label="loc_us-gaap_RestrictedCash_06F5E4C0676458C1C0EA7B9D1A3EB071" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentLineItems_5CCA2682B37644D8C0427B9D1A3D1AF4" xlink:to="loc_us-gaap_RestrictedCash_06F5E4C0676458C1C0EA7B9D1A3EB071" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/DebtTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtDisclosureAbstract" xlink:label="loc_us-gaap_DebtDisclosureAbstract_C87F6633DB7CB07490987B1FFF728324" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfDebtTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfDebtTableTextBlock_B0C724FB68A6C93877A97B1FFF723CC2" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtDisclosureAbstract_C87F6633DB7CB07490987B1FFF728324" xlink:to="loc_us-gaap_ScheduleOfDebtTableTextBlock_B0C724FB68A6C93877A97B1FFF723CC2" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/DocumentAndEntityInformation" xlink:type="extended">
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DocumentAndEntityInformationAbstract" xlink:label="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:type="locator" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_DocumentType" xlink:label="loc_dei_DocumentType_1BC0A8C14FEF3A7E78D298EF0A2EEFB5" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:to="loc_dei_DocumentType_1BC0A8C14FEF3A7E78D298EF0A2EEFB5" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_AmendmentFlag" xlink:label="loc_dei_AmendmentFlag_61CEE424BEA68732641E98EF0A2EC89E" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:to="loc_dei_AmendmentFlag_61CEE424BEA68732641E98EF0A2EC89E" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_DocumentPeriodEndDate" xlink:label="loc_dei_DocumentPeriodEndDate_CC4B095E3A801FCD8A2F98EF0A2F85DF" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:to="loc_dei_DocumentPeriodEndDate_CC4B095E3A801FCD8A2F98EF0A2F85DF" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_DocumentFiscalYearFocus" xlink:label="loc_dei_DocumentFiscalYearFocus_2290EC03FCF9907174EF98EF0A2F29C4" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:to="loc_dei_DocumentFiscalYearFocus_2290EC03FCF9907174EF98EF0A2F29C4" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_DocumentFiscalPeriodFocus" xlink:label="loc_dei_DocumentFiscalPeriodFocus_416986B72DC374F6117D98EF0A2FBF78" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:to="loc_dei_DocumentFiscalPeriodFocus_416986B72DC374F6117D98EF0A2FBF78" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_TradingSymbol" xlink:label="loc_dei_TradingSymbol_39607C405B643B5CC19398EF0A2F1A1B" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:to="loc_dei_TradingSymbol_39607C405B643B5CC19398EF0A2F1A1B" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityRegistrantName" xlink:label="loc_dei_EntityRegistrantName_F4252B7782C27373159198EF0A2FA7A0" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:to="loc_dei_EntityRegistrantName_F4252B7782C27373159198EF0A2FA7A0" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityCentralIndexKey" xlink:label="loc_dei_EntityCentralIndexKey_20745F5043BC6B6E528398EF0A300F9E" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:to="loc_dei_EntityCentralIndexKey_20745F5043BC6B6E528398EF0A300F9E" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_CurrentFiscalYearEndDate" xlink:label="loc_dei_CurrentFiscalYearEndDate_86FBA4E3856A4741DECF98EF0A30D0C4" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:to="loc_dei_CurrentFiscalYearEndDate_86FBA4E3856A4741DECF98EF0A30D0C4" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityFilerCategory" xlink:label="loc_dei_EntityFilerCategory_1AAC4529022CD295304298EF0A309946" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:to="loc_dei_EntityFilerCategory_1AAC4529022CD295304298EF0A309946" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityCommonStockSharesOutstanding" xlink:label="loc_dei_EntityCommonStockSharesOutstanding_D03BE23CFB06EE470C6798EF0A3054CA" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:to="loc_dei_EntityCommonStockSharesOutstanding_D03BE23CFB06EE470C6798EF0A3054CA" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityEmergingGrowthCompany" xlink:label="loc_dei_EntityEmergingGrowthCompany_2E17D60CC2BDDAA46BE998EF0A306209" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:to="loc_dei_EntityEmergingGrowthCompany_2E17D60CC2BDDAA46BE998EF0A306209" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntitySmallBusiness" xlink:label="loc_dei_EntitySmallBusiness_09B60678ECC1C19D501798EF0A304290" xlink:type="locator" />
    <link:presentationArc order="13" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:to="loc_dei_EntitySmallBusiness_09B60678ECC1C19D501798EF0A304290" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd#dei_EntityExTransitionPeriod" xlink:label="loc_dei_EntityExTransitionPeriod_704DBF703D46580AA8AF98EF0D0CB941" xlink:type="locator" />
    <link:presentationArc order="14" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DocumentAndEntityInformationAbstract_636113EB36B1B9B31B6498EF0A2EF898" xlink:to="loc_dei_EntityExTransitionPeriod_704DBF703D46580AA8AF98EF0D0CB941" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/FairValueMeasurements" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueDisclosuresAbstract" xlink:label="loc_us-gaap_FairValueDisclosuresAbstract_C3DFA3D1FF4D7575393352DB8463F45E" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueDisclosuresTextBlock" xlink:label="loc_us-gaap_FairValueDisclosuresTextBlock_6C43F8FE4DCF2A10C3A352F9341DCEC6" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_FairValueDisclosuresAbstract_C3DFA3D1FF4D7575393352DB8463F45E" xlink:to="loc_us-gaap_FairValueDisclosuresTextBlock_6C43F8FE4DCF2A10C3A352F9341DCEC6" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/Inventory" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryDisclosureAbstract" xlink:label="loc_us-gaap_InventoryDisclosureAbstract_7A7041E30A577ECC83BB7B2002E5DFF1" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryDisclosureTextBlock" xlink:label="loc_us-gaap_InventoryDisclosureTextBlock_6A5EC10AF83C7636D7D77B2002E5ECE2" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InventoryDisclosureAbstract_7A7041E30A577ECC83BB7B2002E5DFF1" xlink:to="loc_us-gaap_InventoryDisclosureTextBlock_6A5EC10AF83C7636D7D77B2002E5ECE2" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/InventoryAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryDisclosureAbstract" xlink:label="loc_us-gaap_InventoryDisclosureAbstract_77026F5004C8376978D87B2002722C32" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryValuationReserves" xlink:label="loc_us-gaap_InventoryValuationReserves_AE5C9AF5CAB03DA8E49D7B2002720E0F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InventoryDisclosureAbstract_77026F5004C8376978D87B2002722C32" xlink:to="loc_us-gaap_InventoryValuationReserves_AE5C9AF5CAB03DA8E49D7B2002720E0F" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/InventoryScheduleOfInventoryNetDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryDisclosureAbstract" xlink:label="loc_us-gaap_InventoryDisclosureAbstract_D9A8A63362DE8A085F2C7B1FFFCEBD53" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryRawMaterialsNetOfReserves" xlink:label="loc_us-gaap_InventoryRawMaterialsNetOfReserves_61D4DC0513FE661140F77B1FFFCEB762" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InventoryDisclosureAbstract_D9A8A63362DE8A085F2C7B1FFFCEBD53" xlink:to="loc_us-gaap_InventoryRawMaterialsNetOfReserves_61D4DC0513FE661140F77B1FFFCEB762" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryWorkInProcessNetOfReserves" xlink:label="loc_us-gaap_InventoryWorkInProcessNetOfReserves_0DB0C3927C3A768780427B1FFFDD60DF" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InventoryDisclosureAbstract_D9A8A63362DE8A085F2C7B1FFFCEBD53" xlink:to="loc_us-gaap_InventoryWorkInProcessNetOfReserves_0DB0C3927C3A768780427B1FFFDD60DF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryFinishedGoodsNetOfReserves" xlink:label="loc_us-gaap_InventoryFinishedGoodsNetOfReserves_4F88D0EAC6961481FE957B1FFFDD6BD2" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InventoryDisclosureAbstract_D9A8A63362DE8A085F2C7B1FFFCEBD53" xlink:to="loc_us-gaap_InventoryFinishedGoodsNetOfReserves_4F88D0EAC6961481FE957B1FFFDD6BD2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaap_InventoryNet_BD14A0911008ED4E22F27B1FFFDD4DEB" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InventoryDisclosureAbstract_D9A8A63362DE8A085F2C7B1FFFCEBD53" xlink:to="loc_us-gaap_InventoryNet_BD14A0911008ED4E22F27B1FFFDD4DEB" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/InventoryTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryDisclosureAbstract" xlink:label="loc_us-gaap_InventoryDisclosureAbstract_A8B770F515E6852BD7D97B1FFFDDF097" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfInventoryCurrentTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_BDCDF6C184094EF92B587B1FFFDD39F4" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_InventoryDisclosureAbstract_A8B770F515E6852BD7D97B1FFFDDF097" xlink:to="loc_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_BDCDF6C184094EF92B587B1FFFDD39F4" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/NatureOfOperationsAndOrganization" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:label="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_EF7C05398277BFF7A88B7B200171803F" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OrganizationConsolidationBasisOfPresentationBusinessDescriptionAndAccountingPoliciesTextBlock" xlink:label="loc_us-gaap_OrganizationConsolidationBasisOfPresentationBusinessDescriptionAndAccountingPoliciesTextBlock_7B0D706B1CCEFCB1811D7B200171F322" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_EF7C05398277BFF7A88B7B200171803F" xlink:to="loc_us-gaap_OrganizationConsolidationBasisOfPresentationBusinessDescriptionAndAccountingPoliciesTextBlock_7B0D706B1CCEFCB1811D7B200171F322" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/NetLossPerShare" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract_7CACBE494001E6B5A38C7B1FFFEE29CD" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareTextBlock" xlink:label="loc_us-gaap_EarningsPerShareTextBlock_A6D0E5BE3DA2387A947D7B1FFFEEC16C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareAbstract_7CACBE494001E6B5A38C7B1FFFEE29CD" xlink:to="loc_us-gaap_EarningsPerShareTextBlock_A6D0E5BE3DA2387A947D7B1FFFEEC16C" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/NetLossPerShareAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract_2356DEA49742C506F09B7B2001E48A66" xlink:type="locator" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_EarningsPerShareTable" xlink:label="loc_vlrx_EarningsPerShareTable_24B972FD4B52D10C84A27B2001E47C90" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareAbstract_2356DEA49742C506F09B7B2001E48A66" xlink:to="loc_vlrx_EarningsPerShareTable_24B972FD4B52D10C84A27B2001E47C90" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaap_StatementClassOfStockAxis_3A178979BE833DA8DD687B2001E4D1B6" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_EarningsPerShareTable_24B972FD4B52D10C84A27B2001E47C90" xlink:to="loc_us-gaap_StatementClassOfStockAxis_3A178979BE833DA8DD687B2001E4D1B6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_2AD15F20D282CD7E37537B2001E4BD73" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementClassOfStockAxis_3A178979BE833DA8DD687B2001E4D1B6" xlink:to="loc_us-gaap_ClassOfStockDomain_2AD15F20D282CD7E37537B2001E4BD73" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeriesAPreferredStockMember" xlink:label="loc_us-gaap_SeriesAPreferredStockMember_71B6AF41DE42EDF36C097B2001E47518" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockDomain_2AD15F20D282CD7E37537B2001E4BD73" xlink:to="loc_us-gaap_SeriesAPreferredStockMember_71B6AF41DE42EDF36C097B2001E47518" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_EarningsPerShareLineItems" xlink:label="loc_vlrx_EarningsPerShareLineItems_CEFEF164D45F721A93CF7B2001E48730" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_EarningsPerShareTable_24B972FD4B52D10C84A27B2001E47C90" xlink:to="loc_vlrx_EarningsPerShareLineItems_CEFEF164D45F721A93CF7B2001E48730" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_PreferredStockDividendRatePerOneHundredDollarsOfStock" xlink:label="loc_vlrx_PreferredStockDividendRatePerOneHundredDollarsOfStock_181C161602B70AE05E267B2001E40575" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_EarningsPerShareLineItems_CEFEF164D45F721A93CF7B2001E48730" xlink:to="loc_vlrx_PreferredStockDividendRatePerOneHundredDollarsOfStock_181C161602B70AE05E267B2001E40575" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/NetLossPerShareScheduleOfAntidilutiveOptionsNotIncludedInComputationOfWeightedAverageCommonSharesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract_0CBA036A03F510053DB79988DBC36E1B" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_57ECDB62A9B8409BD38F9988DBC6B188" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareAbstract_0CBA036A03F510053DB79988DBC36E1B" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_57ECDB62A9B8409BD38F9988DBC6B188" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_5FCD96E8037D0EDB144F9988DBC8624C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_57ECDB62A9B8409BD38F9988DBC6B188" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_5FCD96E8037D0EDB144F9988DBC8624C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_1B986A5CB38D8EF9FF179988DBC8704F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_5FCD96E8037D0EDB144F9988DBC8624C" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_1B986A5CB38D8EF9FF179988DBC8704F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="loc_us-gaap_EmployeeStockOptionMember_750BEC59858F7301E1639988DBC89892" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_1B986A5CB38D8EF9FF179988DBC8704F" xlink:to="loc_us-gaap_EmployeeStockOptionMember_750BEC59858F7301E1639988DBC89892" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_WarrantMember" xlink:label="loc_us-gaap_WarrantMember_F28CE8C055C2A6A83CDD9988DBCB138D" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_1B986A5CB38D8EF9FF179988DBC8704F" xlink:to="loc_us-gaap_WarrantMember_F28CE8C055C2A6A83CDD9988DBCB138D" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SeriesAandBWarrantsMember" xlink:label="loc_vlrx_SeriesAandBWarrantsMember_94663EFF9F7C5B31E9399988DED11BEA" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_1B986A5CB38D8EF9FF179988DBC8704F" xlink:to="loc_vlrx_SeriesAandBWarrantsMember_94663EFF9F7C5B31E9399988DED11BEA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockMember" xlink:label="loc_us-gaap_PreferredStockMember_FC79FF532DC99260A8DC9988DBCC6E6A" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_1B986A5CB38D8EF9FF179988DBC8704F" xlink:to="loc_us-gaap_PreferredStockMember_FC79FF532DC99260A8DC9988DBCC6E6A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeStockMember" xlink:label="loc_us-gaap_EmployeeStockMember_A5FCD8F5239CB0CD049E9988DBCC8882" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_1B986A5CB38D8EF9FF179988DBC8704F" xlink:to="loc_us-gaap_EmployeeStockMember_A5FCD8F5239CB0CD049E9988DBCC8882" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_7BDB6C5BAB5B55D4E1DF9988DBCC34FB" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_57ECDB62A9B8409BD38F9988DBC6B188" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_7BDB6C5BAB5B55D4E1DF9988DBCC34FB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_FD910AC42DC78DAE03779988DBCC09FD" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_7BDB6C5BAB5B55D4E1DF9988DBCC34FB" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_FD910AC42DC78DAE03779988DBCC09FD" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/NetLossPerShareTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract_CA2758271622BD02C8907B2002E59817" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_0CEC862460A6A6A788EE7B2002E5CDBD" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EarningsPerShareAbstract_CA2758271622BD02C8907B2002E59817" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_0CEC862460A6A6A788EE7B2002E5CDBD" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/PropertyAndEquipment" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAbstract" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAbstract_6E0BA0B91C1631348AB17B20018060EE" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_6E488F2F087F803560917B2001806672" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract_6E0BA0B91C1631348AB17B20018060EE" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_6E488F2F087F803560917B2001806672" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/PropertyAndEquipmentAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAbstract" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAbstract_CA162D57B3EFDB6237F87ED5B4EA515D" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_907A338F352810DBC7E37ED5B4EAC547" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract_CA162D57B3EFDB6237F87ED5B4EA515D" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_907A338F352810DBC7E37ED5B4EAC547" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/PropertyAndEquipmentScheduleOfPropertyAndEquipmentDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAbstract" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAbstract_1B45B1CB8EAE66A021F27B2003068CE9" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_E384D2DF0E94555CAFFF7B2003065A98" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract_1B45B1CB8EAE66A021F27B2003068CE9" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_E384D2DF0E94555CAFFF7B2003065A98" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_575CFA96EC779B1870A37B20030671F8" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_E384D2DF0E94555CAFFF7B2003065A98" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_575CFA96EC779B1870A37B20030671F8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_4941895CD3E6FADF03867B200306F261" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_575CFA96EC779B1870A37B20030671F8" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_4941895CD3E6FADF03867B200306F261" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MachineryAndEquipmentMember" xlink:label="loc_us-gaap_MachineryAndEquipmentMember_67AD723C5E90C1B6CCCC7B2003065F18" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_4941895CD3E6FADF03867B200306F261" xlink:to="loc_us-gaap_MachineryAndEquipmentMember_67AD723C5E90C1B6CCCC7B2003065F18" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ComputersAndSoftwareMember" xlink:label="loc_vlrx_ComputersAndSoftwareMember_84DF4821BC73DAD8CE787B20030642C7" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_4941895CD3E6FADF03867B200306F261" xlink:to="loc_vlrx_ComputersAndSoftwareMember_84DF4821BC73DAD8CE787B20030642C7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LeaseholdImprovementsMember" xlink:label="loc_us-gaap_LeaseholdImprovementsMember_34A180216BAA5B78AD767B200306926F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_4941895CD3E6FADF03867B200306F261" xlink:to="loc_us-gaap_LeaseholdImprovementsMember_34A180216BAA5B78AD767B200306926F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OfficeEquipmentMember" xlink:label="loc_us-gaap_OfficeEquipmentMember_98C52351F5CB84E4A7E37B2003061C11" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_4941895CD3E6FADF03867B200306F261" xlink:to="loc_us-gaap_OfficeEquipmentMember_98C52351F5CB84E4A7E37B2003061C11" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FurnitureAndFixturesMember" xlink:label="loc_us-gaap_FurnitureAndFixturesMember_6F3C06ED78D6BFE2DEF27B200306C615" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_4941895CD3E6FADF03867B200306F261" xlink:to="loc_us-gaap_FurnitureAndFixturesMember_6F3C06ED78D6BFE2DEF27B200306C615" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ConstructionInProgressMember" xlink:label="loc_us-gaap_ConstructionInProgressMember_19BC0275CA89ECBA126D7B200306C230" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_4941895CD3E6FADF03867B200306F261" xlink:to="loc_us-gaap_ConstructionInProgressMember_19BC0275CA89ECBA126D7B200306C230" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="loc_srt_RangeAxis_348DC5D5CA7ECB6E9A887B2003062E78" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_E384D2DF0E94555CAFFF7B2003065A98" xlink:to="loc_srt_RangeAxis_348DC5D5CA7ECB6E9A887B2003062E78" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_5483F48F0AB06A36EC457B2003065534" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RangeAxis_348DC5D5CA7ECB6E9A887B2003062E78" xlink:to="loc_srt_RangeMember_5483F48F0AB06A36EC457B2003065534" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MinimumMember" xlink:label="loc_srt_MinimumMember_C9269B5BEBB8DC422C287B200306D931" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RangeMember_5483F48F0AB06A36EC457B2003065534" xlink:to="loc_srt_MinimumMember_C9269B5BEBB8DC422C287B200306D931" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="loc_srt_MaximumMember_EBCD4387F30F57A830A07B200306CE0B" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RangeMember_5483F48F0AB06A36EC457B2003065534" xlink:to="loc_srt_MaximumMember_EBCD4387F30F57A830A07B200306CE0B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentLineItems" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_2A3CEA0E1CF602D3A6317B20030695D5" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_E384D2DF0E94555CAFFF7B2003065A98" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentLineItems_2A3CEA0E1CF602D3A6317B20030695D5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_06E0AE039A3428CE29267B2003064285" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_2A3CEA0E1CF602D3A6317B20030695D5" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_06E0AE039A3428CE29267B2003064285" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_8F5C63CEB1C3302743BC7B200306C0D2" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_2A3CEA0E1CF602D3A6317B20030695D5" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentGross_8F5C63CEB1C3302743BC7B200306C0D2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_FB9D0DC8787755F664797B200306DD37" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_2A3CEA0E1CF602D3A6317B20030695D5" xlink:to="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_FB9D0DC8787755F664797B200306DD37" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_A306D6BA59628C3CD69C7B200306B7C0" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/totalLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_2A3CEA0E1CF602D3A6317B20030695D5" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_A306D6BA59628C3CD69C7B200306B7C0" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/PropertyAndEquipmentTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAbstract" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAbstract_63724BB690ED79C88E037B2001715E12" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTextBlock_54FB6E1C052291641A867B200171EB1D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract_63724BB690ED79C88E037B2001715E12" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTextBlock_54FB6E1C052291641A867B200171EB1D" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/RelatedPartyTransactions" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionsAbstract" xlink:label="loc_us-gaap_RelatedPartyTransactionsAbstract_D080F332A7E1C0BC5AF67B2001C5254A" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:label="loc_us-gaap_RelatedPartyTransactionsDisclosureTextBlock_FF15D0F04ABB822E856A7B2001C50259" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionsAbstract_D080F332A7E1C0BC5AF67B2001C5254A" xlink:to="loc_us-gaap_RelatedPartyTransactionsDisclosureTextBlock_FF15D0F04ABB822E856A7B2001C50259" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/RelatedPartyTransactionsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionsAbstract" xlink:label="loc_us-gaap_RelatedPartyTransactionsAbstract_38B66922C0AFF384FB1C996208183663" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_5B987B501DB952C5EDEF996208188C8D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionsAbstract_38B66922C0AFF384FB1C996208183663" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_5B987B501DB952C5EDEF996208188C8D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_3675BF064776ED49B3C999620818C3DC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_5B987B501DB952C5EDEF996208188C8D" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_3675BF064776ED49B3C999620818C3DC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaap_RelatedPartyDomain_D0EE7436DF117611401C99620819558F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_3675BF064776ED49B3C999620818C3DC" xlink:to="loc_us-gaap_RelatedPartyDomain_D0EE7436DF117611401C99620819558F" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CapitalRoyaltyPartnersMember" xlink:label="loc_vlrx_CapitalRoyaltyPartnersMember_0BAF1CE3DF2077E3DD0C99620819C679" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyDomain_D0EE7436DF117611401C99620819558F" xlink:to="loc_vlrx_CapitalRoyaltyPartnersMember_0BAF1CE3DF2077E3DD0C99620819C679" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightAxis" xlink:label="loc_us-gaap_ClassOfWarrantOrRightAxis_86A9563F553223FFC72C996208199501" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_5B987B501DB952C5EDEF996208188C8D" xlink:to="loc_us-gaap_ClassOfWarrantOrRightAxis_86A9563F553223FFC72C996208199501" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightDomain" xlink:label="loc_us-gaap_ClassOfWarrantOrRightDomain_D0D37864D600B1CDB06A99620819BF72" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightAxis_86A9563F553223FFC72C996208199501" xlink:to="loc_us-gaap_ClassOfWarrantOrRightDomain_D0D37864D600B1CDB06A99620819BF72" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SeriesAWarrantsMember" xlink:label="loc_vlrx_SeriesAWarrantsMember_9FA77A933564202BE7039962081A735D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightDomain_D0D37864D600B1CDB06A99620819BF72" xlink:to="loc_vlrx_SeriesAWarrantsMember_9FA77A933564202BE7039962081A735D" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SeriesBWarrantsMember" xlink:label="loc_vlrx_SeriesBWarrantsMember_E8E003595524C434D08E9962081A19F6" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightDomain_D0D37864D600B1CDB06A99620819BF72" xlink:to="loc_vlrx_SeriesBWarrantsMember_E8E003595524C434D08E9962081A19F6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaap_RelatedPartyTransactionAxis_0437F39DB021C5C3E13D9962081AEAFC" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_5B987B501DB952C5EDEF996208188C8D" xlink:to="loc_us-gaap_RelatedPartyTransactionAxis_0437F39DB021C5C3E13D9962081AEAFC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_C64222ED6B6AD29680DA9962081AE352" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionAxis_0437F39DB021C5C3E13D9962081AEAFC" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_C64222ED6B6AD29680DA9962081AE352" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember" xlink:label="loc_vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember_F93A0565C4FAC31546CE9962081B7F9C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_C64222ED6B6AD29680DA9962081AE352" xlink:to="loc_vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember_F93A0565C4FAC31546CE9962081B7F9C" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DebtConversionCapitalRoyaltyPartnersMember" xlink:label="loc_vlrx_DebtConversionCapitalRoyaltyPartnersMember_3E6A89D1BE69A9FF02A79962081BCEE5" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember_F93A0565C4FAC31546CE9962081B7F9C" xlink:to="loc_vlrx_DebtConversionCapitalRoyaltyPartnersMember_3E6A89D1BE69A9FF02A79962081BCEE5" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DebtConversionWCASMember" xlink:label="loc_vlrx_DebtConversionWCASMember_9ADFBF76FE2426E938E59962081BAF31" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember_F93A0565C4FAC31546CE9962081B7F9C" xlink:to="loc_vlrx_DebtConversionWCASMember_9ADFBF76FE2426E938E59962081BAF31" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_AD19A937DB49D4F7D5689962081B5BB6" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_5B987B501DB952C5EDEF996208188C8D" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_AD19A937DB49D4F7D5689962081B5BB6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_7F25AEC9CD3A5AF4F3069962081C0442" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_AD19A937DB49D4F7D5689962081B5BB6" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_7F25AEC9CD3A5AF4F3069962081C0442" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SecuredDebtMember" xlink:label="loc_us-gaap_SecuredDebtMember_50B16464E687D9666F989962081CBC54" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_7F25AEC9CD3A5AF4F3069962081C0442" xlink:to="loc_us-gaap_SecuredDebtMember_50B16464E687D9666F989962081CBC54" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaap_StatementClassOfStockAxis_0AA9D26BB5EEC3C28F949962081C8F73" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_5B987B501DB952C5EDEF996208188C8D" xlink:to="loc_us-gaap_StatementClassOfStockAxis_0AA9D26BB5EEC3C28F949962081C8F73" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_777836D57EC662C632069962081CAC01" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementClassOfStockAxis_0AA9D26BB5EEC3C28F949962081C8F73" xlink:to="loc_us-gaap_ClassOfStockDomain_777836D57EC662C632069962081CAC01" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeriesAPreferredStockMember" xlink:label="loc_us-gaap_SeriesAPreferredStockMember_7C741220281C5254B1A59962081DF7A5" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockDomain_777836D57EC662C632069962081CAC01" xlink:to="loc_us-gaap_SeriesAPreferredStockMember_7C741220281C5254B1A59962081DF7A5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_251BA7415F1D66DFA7A49962081D75D7" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_5B987B501DB952C5EDEF996208188C8D" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_251BA7415F1D66DFA7A49962081D75D7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_FB1733493CB68A5691349962081D66DE" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_251BA7415F1D66DFA7A49962081D75D7" xlink:to="loc_us-gaap_EquityComponentDomain_FB1733493CB68A5691349962081D66DE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember_6A9480F75A72CE4CD7099962081D2A3F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_FB1733493CB68A5691349962081D66DE" xlink:to="loc_us-gaap_CommonStockMember_6A9480F75A72CE4CD7099962081D2A3F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockMember" xlink:label="loc_us-gaap_PreferredStockMember_61A30E21C99B463047919962081E4EDB" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_FB1733493CB68A5691349962081D66DE" xlink:to="loc_us-gaap_PreferredStockMember_61A30E21C99B463047919962081E4EDB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionLineItems" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_70B8D640A76C2354ABDA9962081EA6B5" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_5B987B501DB952C5EDEF996208188C8D" xlink:to="loc_us-gaap_RelatedPartyTransactionLineItems_70B8D640A76C2354ABDA9962081EA6B5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_67847DF380B991D2DB109962081E3FBF" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_70B8D640A76C2354ABDA9962081EA6B5" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_67847DF380B991D2DB109962081E3FBF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_E2175F173D1A1B5768B69962081E6D50" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_70B8D640A76C2354ABDA9962081EA6B5" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_E2175F173D1A1B5768B69962081E6D50" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassOfWarrantOrRightIssued" xlink:label="loc_vlrx_ClassOfWarrantOrRightIssued_1070312608744550DC4B9962081E0D71" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_70B8D640A76C2354ABDA9962081EA6B5" xlink:to="loc_vlrx_ClassOfWarrantOrRightIssued_1070312608744550DC4B9962081E0D71" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_2FB7D477E016D779E56D9962081EE1C3" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_70B8D640A76C2354ABDA9962081EA6B5" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_2FB7D477E016D779E56D9962081EE1C3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtConversionOriginalDebtAmount1" xlink:label="loc_us-gaap_DebtConversionOriginalDebtAmount1_2030FD2ED5E740333B129962081F9687" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_70B8D640A76C2354ABDA9962081EA6B5" xlink:to="loc_us-gaap_DebtConversionOriginalDebtAmount1_2030FD2ED5E740333B129962081F9687" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtConversionConvertedInstrumentSharesIssued1" xlink:label="loc_us-gaap_DebtConversionConvertedInstrumentSharesIssued1_D33B04825030A3FED2919962081F6D2D" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_70B8D640A76C2354ABDA9962081EA6B5" xlink:to="loc_us-gaap_DebtConversionConvertedInstrumentSharesIssued1_D33B04825030A3FED2919962081F6D2D" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/RevenueFromContractWithCustomers" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueFromContractWithCustomerAbstract" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerAbstract_F5B8FCDB16CA8B02CFD260E8B0AD0C05" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueFromContractWithCustomerTextBlock" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerTextBlock_B6C9B12FB6DCE0A3850A60E8EC944FD8" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RevenueFromContractWithCustomerAbstract_F5B8FCDB16CA8B02CFD260E8B0AD0C05" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerTextBlock_B6C9B12FB6DCE0A3850A60E8EC944FD8" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/StockholdersEquityDeficit" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityAbstract" xlink:label="loc_us-gaap_EquityAbstract_79526C3E0669298B199C7F16A74DCC27" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareholdersEquityAndShareBasedPaymentsTextBlock" xlink:label="loc_us-gaap_ShareholdersEquityAndShareBasedPaymentsTextBlock_173E3A7EC8C51CAAC0AA7F16A74D4C60" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityAbstract_79526C3E0669298B199C7F16A74DCC27" xlink:to="loc_us-gaap_ShareholdersEquityAndShareBasedPaymentsTextBlock_173E3A7EC8C51CAAC0AA7F16A74D4C60" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/StockholdersEquityDeficitEquityCompensationPlansDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityAbstract" xlink:label="loc_us-gaap_EquityAbstract_22C86C7216CCCF04636E985668D62805" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_19FF1610BFCD122D6785985668D70A56" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityAbstract_22C86C7216CCCF04636E985668D62805" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_19FF1610BFCD122D6785985668D70A56" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="loc_srt_RangeAxis_9EB6A97D3CE0DA524711985668D8768F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_19FF1610BFCD122D6785985668D70A56" xlink:to="loc_srt_RangeAxis_9EB6A97D3CE0DA524711985668D8768F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_42A937FB18BF20FFF46E985668D97024" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RangeAxis_9EB6A97D3CE0DA524711985668D8768F" xlink:to="loc_srt_RangeMember_42A937FB18BF20FFF46E985668D97024" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MinimumMember" xlink:label="loc_srt_MinimumMember_134EDD5516CD4716230A985668D98088" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RangeMember_42A937FB18BF20FFF46E985668D97024" xlink:to="loc_srt_MinimumMember_134EDD5516CD4716230A985668D98088" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="loc_srt_MaximumMember_E4862429BAA07E51A26D985668DABE5A" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RangeMember_42A937FB18BF20FFF46E985668D97024" xlink:to="loc_srt_MaximumMember_E4862429BAA07E51A26D985668DABE5A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaap_PlanNameAxis_495F32833BAC5E313195985668DA29B0" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_19FF1610BFCD122D6785985668D70A56" xlink:to="loc_us-gaap_PlanNameAxis_495F32833BAC5E313195985668DA29B0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaap_PlanNameDomain_792F8F28DC7A144AC104985668DB1191" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameAxis_495F32833BAC5E313195985668DA29B0" xlink:to="loc_us-gaap_PlanNameDomain_792F8F28DC7A144AC104985668DB1191" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanTwoThousandEighteenInducementPlanMember" xlink:label="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanTwoThousandEighteenInducementPlanMember_0DCEFE854C93640A7A9B985668DBDA4A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_792F8F28DC7A144AC104985668DB1191" xlink:to="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanTwoThousandEighteenInducementPlanMember_0DCEFE854C93640A7A9B985668DBDA4A" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanMember" xlink:label="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanMember_3A7D6FBC35A1597F088B985668DDC0DC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanTwoThousandEighteenInducementPlanMember_0DCEFE854C93640A7A9B985668DBDA4A" xlink:to="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanMember_3A7D6FBC35A1597F088B985668DDC0DC" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_TwoThousandEighteenInducementPlanMember" xlink:label="loc_vlrx_TwoThousandEighteenInducementPlanMember_AEE8BC07CD1AF932F599985668DD6244" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanTwoThousandEighteenInducementPlanMember_0DCEFE854C93640A7A9B985668DBDA4A" xlink:to="loc_vlrx_TwoThousandEighteenInducementPlanMember_AEE8BC07CD1AF932F599985668DD6244" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis_6CBE5FD0559FD76F0D99985668DED475" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_19FF1610BFCD122D6785985668D70A56" xlink:to="loc_us-gaap_AwardTypeAxis_6CBE5FD0559FD76F0D99985668DED475" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_98CBC8CFDA2DE9EF94A8985668DEA3E3" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_AwardTypeAxis_6CBE5FD0559FD76F0D99985668DED475" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_98CBC8CFDA2DE9EF94A8985668DEA3E3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeStockMember" xlink:label="loc_us-gaap_EmployeeStockMember_A7FB0D127B189C4BAAD1985668DFDF2F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_98CBC8CFDA2DE9EF94A8985668DEA3E3" xlink:to="loc_us-gaap_EmployeeStockMember_A7FB0D127B189C4BAAD1985668DFDF2F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_56F135AC69EEB4977166985668E0D292" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_19FF1610BFCD122D6785985668D70A56" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_56F135AC69EEB4977166985668E0D292" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_EmployeeStockPurchasePlansCapitalSharesOutstandingAuthorizedPercent" xlink:label="loc_vlrx_EmployeeStockPurchasePlansCapitalSharesOutstandingAuthorizedPercent_F8B7E200C7DE1A295A12985668E119AC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_56F135AC69EEB4977166985668E0D292" xlink:to="loc_vlrx_EmployeeStockPurchasePlansCapitalSharesOutstandingAuthorizedPercent_F8B7E200C7DE1A295A12985668E119AC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent_B7F95C9C40FEE92E27A2985668E26EEB" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_56F135AC69EEB4977166985668E0D292" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardPurchasePriceOfCommonStockPercent_B7F95C9C40FEE92E27A2985668E26EEB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardDiscountFromMarketPriceOfferingDate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardDiscountFromMarketPriceOfferingDate_8C457AB212A190BCBF35985668E24A1F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_56F135AC69EEB4977166985668E0D292" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardDiscountFromMarketPriceOfferingDate_8C457AB212A190BCBF35985668E24A1F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_5EF99362CC412071980E985668E373F6" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_56F135AC69EEB4977166985668E0D292" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_5EF99362CC412071980E985668E373F6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" xlink:label="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_CF42B57AB7D3C932EDDB985668E389BC" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_56F135AC69EEB4977166985668E0D292" xlink:to="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_CF42B57AB7D3C932EDDB985668E389BC" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CommonStockCapitalSharesReservedforFutureIssuanceAnnualIncreasePercent" xlink:label="loc_vlrx_CommonStockCapitalSharesReservedforFutureIssuanceAnnualIncreasePercent_76FB9E78CB627F8E5A0D985668E36B9F" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_56F135AC69EEB4977166985668E0D292" xlink:to="loc_vlrx_CommonStockCapitalSharesReservedforFutureIssuanceAnnualIncreasePercent_76FB9E78CB627F8E5A0D985668E36B9F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_C664717E86A7730FF108985668E3B482" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_56F135AC69EEB4977166985668E0D292" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_C664717E86A7730FF108985668E3B482" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_1765A3C19F9594D7B77A985668E4435D" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_56F135AC69EEB4977166985668E0D292" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_1765A3C19F9594D7B77A985668E4435D" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SharebasedCompensationArrangementbySharebasedPaymentAwardNumberofAdditionalSharesAvailableforGrant" xlink:label="loc_vlrx_SharebasedCompensationArrangementbySharebasedPaymentAwardNumberofAdditionalSharesAvailableforGrant_A9DAAE94502CD79FC6CD985668E4CCFB" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_56F135AC69EEB4977166985668E0D292" xlink:to="loc_vlrx_SharebasedCompensationArrangementbySharebasedPaymentAwardNumberofAdditionalSharesAvailableforGrant_A9DAAE94502CD79FC6CD985668E4CCFB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_AB50F86506B41A9BD830985668E49182" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_56F135AC69EEB4977166985668E0D292" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_AB50F86506B41A9BD830985668E49182" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_9BBF4AF568A5FD8CED49985668E62DFB" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_56F135AC69EEB4977166985668E0D292" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_9BBF4AF568A5FD8CED49985668E62DFB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_3B941C87FB63EEAC45CE985668E6A20F" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_56F135AC69EEB4977166985668E0D292" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_3B941C87FB63EEAC45CE985668E6A20F" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/StockholdersEquityDeficitNarrativeDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityAbstract" xlink:label="loc_us-gaap_EquityAbstract_45D4902AD0A7FB49B4879DDFFCF5F570" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfStockByClassTable" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityAbstract_45D4902AD0A7FB49B4879DDFFCF5F570" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_2323C3EDD254A6C42E579DDFFCF5115A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_2323C3EDD254A6C42E579DDFFCF5115A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_B35D109982160F69104B9DDFFCF5B78B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_2323C3EDD254A6C42E579DDFFCF5115A" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_B35D109982160F69104B9DDFFCF5B78B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaap_SubsequentEventMember_6CC7DC26079419852E519DDFFCF6896F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_B35D109982160F69104B9DDFFCF5B78B" xlink:to="loc_us-gaap_SubsequentEventMember_6CC7DC26079419852E519DDFFCF6896F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_A201C8D25323EE11D02C9DDFFCF6DC06" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_A201C8D25323EE11D02C9DDFFCF6DC06" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_C1778023E89B38BC76479DDFFCF6F6D0" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_A201C8D25323EE11D02C9DDFFCF6DC06" xlink:to="loc_us-gaap_EquityComponentDomain_C1778023E89B38BC76479DDFFCF6F6D0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember_8C05A2D140A20FAC0A069DDFFCF70DB8" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_C1778023E89B38BC76479DDFFCF6F6D0" xlink:to="loc_us-gaap_CommonStockMember_8C05A2D140A20FAC0A069DDFFCF70DB8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockMember" xlink:label="loc_us-gaap_PreferredStockMember_9F7A96D94BFA09D50E879DDFFCF7121C" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityComponentDomain_C1778023E89B38BC76479DDFFCF6F6D0" xlink:to="loc_us-gaap_PreferredStockMember_9F7A96D94BFA09D50E879DDFFCF7121C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis_E650714157B49877CF7C9DDFFCF763B8" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:to="loc_us-gaap_SubsidiarySaleOfStockAxis_E650714157B49877CF7C9DDFFCF763B8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_7419B904C63FF9E7FA809DDFFCF70520" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_E650714157B49877CF7C9DDFFCF763B8" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_7419B904C63FF9E7FA809DDFFCF70520" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IPOMember" xlink:label="loc_us-gaap_IPOMember_2996A1CA28A134778A8D9DDFFCF7998B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_7419B904C63FF9E7FA809DDFFCF70520" xlink:to="loc_us-gaap_IPOMember_2996A1CA28A134778A8D9DDFFCF7998B" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SupplementalProctusMember" xlink:label="loc_vlrx_SupplementalProctusMember_05F27BCEFF5C4F24ACEB9DDFFCF8FA9D" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_7419B904C63FF9E7FA809DDFFCF70520" xlink:to="loc_vlrx_SupplementalProctusMember_05F27BCEFF5C4F24ACEB9DDFFCF8FA9D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OverAllotmentOptionMember" xlink:label="loc_us-gaap_OverAllotmentOptionMember_3082BE98C4A3F90F4DDB9DDFFCF8D06F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_7419B904C63FF9E7FA809DDFFCF70520" xlink:to="loc_us-gaap_OverAllotmentOptionMember_3082BE98C4A3F90F4DDB9DDFFCF8D06F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionAxis" xlink:label="loc_us-gaap_RelatedPartyTransactionAxis_49AAC1E32FAACDB30E0F9DDFFCF82ADE" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:to="loc_us-gaap_RelatedPartyTransactionAxis_49AAC1E32FAACDB30E0F9DDFFCF82ADE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RelatedPartyTransactionDomain" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_1F38D23D5938322E28EA9DDFFCF8D31B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionAxis_49AAC1E32FAACDB30E0F9DDFFCF82ADE" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_1F38D23D5938322E28EA9DDFFCF8D31B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InvestorMember" xlink:label="loc_us-gaap_InvestorMember_A4C259CB90964F56DB9D9DDFFCF91EA1" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_1F38D23D5938322E28EA9DDFFCF8D31B" xlink:to="loc_us-gaap_InvestorMember_A4C259CB90964F56DB9D9DDFFCF91EA1" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DebtConversionCapitalRoyaltyPartnersMember" xlink:label="loc_vlrx_DebtConversionCapitalRoyaltyPartnersMember_BE55DE7EAE5945EEF4589DDFFCF956AE" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_1F38D23D5938322E28EA9DDFFCF8D31B" xlink:to="loc_vlrx_DebtConversionCapitalRoyaltyPartnersMember_BE55DE7EAE5945EEF4589DDFFCF956AE" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DebtConversionWCASMember" xlink:label="loc_vlrx_DebtConversionWCASMember_F82E887AC5EC7C70195B9DDFFCF97E40" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_1F38D23D5938322E28EA9DDFFCF8D31B" xlink:to="loc_vlrx_DebtConversionWCASMember_F82E887AC5EC7C70195B9DDFFCF97E40" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember" xlink:label="loc_vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember_F2078826B5BDEBAF68699DDFFCF945AE" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_1F38D23D5938322E28EA9DDFFCF8D31B" xlink:to="loc_vlrx_DebtConversionCapitalRoyaltyPartnersAndWCASMember_F2078826B5BDEBAF68699DDFFCF945AE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_61EB3CD9BE869A6F3B1F9DDFFCF9AD0F" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_61EB3CD9BE869A6F3B1F9DDFFCF9AD0F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_81538F719B21F55773C59DDFFCF98C17" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_61EB3CD9BE869A6F3B1F9DDFFCF9AD0F" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_81538F719B21F55773C59DDFFCF98C17" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SecuredDebtMember" xlink:label="loc_us-gaap_SecuredDebtMember_88E1051008CA260054499DDFFCFAAA49" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_81538F719B21F55773C59DDFFCF98C17" xlink:to="loc_us-gaap_SecuredDebtMember_88E1051008CA260054499DDFFCFAAA49" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NotesPayableOtherPayablesMember" xlink:label="loc_us-gaap_NotesPayableOtherPayablesMember_142E1846D417F26EC8AD9DDFFCFA191E" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_81538F719B21F55773C59DDFFCF98C17" xlink:to="loc_us-gaap_NotesPayableOtherPayablesMember_142E1846D417F26EC8AD9DDFFCFA191E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringPlanAxis" xlink:label="loc_us-gaap_RestructuringPlanAxis_94BE7FE2696E0F1BBFE29DDFFCFA6EDA" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:to="loc_us-gaap_RestructuringPlanAxis_94BE7FE2696E0F1BBFE29DDFFCFA6EDA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringPlanDomain" xlink:label="loc_us-gaap_RestructuringPlanDomain_471FEEEE85D1E58DB3699DDFFCFAF761" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RestructuringPlanAxis_94BE7FE2696E0F1BBFE29DDFFCFA6EDA" xlink:to="loc_us-gaap_RestructuringPlanDomain_471FEEEE85D1E58DB3699DDFFCFAF761" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_RestructuredDebtMember" xlink:label="loc_vlrx_RestructuredDebtMember_0257D39C45906C32D2C89DDFFCFA5A9C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_RestructuringPlanDomain_471FEEEE85D1E58DB3699DDFFCFAF761" xlink:to="loc_vlrx_RestructuredDebtMember_0257D39C45906C32D2C89DDFFCFA5A9C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_DD9FAC2616FD1FC27CCF9DDFFCFBCFA1" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:to="loc_us-gaap_DebtInstrumentAxis_DD9FAC2616FD1FC27CCF9DDFFCFBCFA1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_0F4F2B455D4E80D27E0A9DDFFCFB0FFB" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentAxis_DD9FAC2616FD1FC27CCF9DDFFCFBCFA1" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_0F4F2B455D4E80D27E0A9DDFFCFB0FFB" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_WcasCapitalPartnersIvLpMember" xlink:label="loc_vlrx_WcasCapitalPartnersIvLpMember_206D9E1C456A120DFAFB9DDFFCFB42A2" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_0F4F2B455D4E80D27E0A9DDFFCFB0FFB" xlink:to="loc_vlrx_WcasCapitalPartnersIvLpMember_206D9E1C456A120DFAFB9DDFFCFB42A2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaap_StatementClassOfStockAxis_A9517F64DC7946FFDB659DDFFCFB6C37" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:to="loc_us-gaap_StatementClassOfStockAxis_A9517F64DC7946FFDB659DDFFCFB6C37" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_FF4BD79422D048FE11D89DDFFCFC914D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_StatementClassOfStockAxis_A9517F64DC7946FFDB659DDFFCFB6C37" xlink:to="loc_us-gaap_ClassOfStockDomain_FF4BD79422D048FE11D89DDFFCFC914D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeriesAPreferredStockMember" xlink:label="loc_us-gaap_SeriesAPreferredStockMember_08C6B0D051D4E4F797DD9DDFFCFCDD62" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockDomain_FF4BD79422D048FE11D89DDFFCFC914D" xlink:to="loc_us-gaap_SeriesAPreferredStockMember_08C6B0D051D4E4F797DD9DDFFCFCDD62" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_CounterpartyNameAxis" xlink:label="loc_srt_CounterpartyNameAxis_BF9DFE0BB5B0C2B9BFF29DDFFCFC371C" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:to="loc_srt_CounterpartyNameAxis_BF9DFE0BB5B0C2B9BFF29DDFFCFC371C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_DDDBEF26EA77131BCC249DDFFCFCBE4C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_CounterpartyNameAxis_BF9DFE0BB5B0C2B9BFF29DDFFCFC371C" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_DDDBEF26EA77131BCC249DDFFCFCBE4C" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_AspireCapitalFundLLCMember" xlink:label="loc_vlrx_AspireCapitalFundLLCMember_163044008D5152BDAAA39DDFFCFD7C3D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_DDDBEF26EA77131BCC249DDFFCFCBE4C" xlink:to="loc_vlrx_AspireCapitalFundLLCMember_163044008D5152BDAAA39DDFFCFD7C3D" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_B.RileyFBRInc.Member" xlink:label="loc_vlrx_B.RileyFBRInc.Member_91D4DC0C2E8B0B170DBE9DDFFCFDE0B3" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_DDDBEF26EA77131BCC249DDFFCFCBE4C" xlink:to="loc_vlrx_B.RileyFBRInc.Member_91D4DC0C2E8B0B170DBE9DDFFCFDE0B3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaap_PlanNameAxis_FCA09E19C58634218BF79DDFFCFD0D4C" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:to="loc_us-gaap_PlanNameAxis_FCA09E19C58634218BF79DDFFCFD0D4C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaap_PlanNameDomain_8B591AD362C9940C78B49DDFFCFD65E1" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameAxis_FCA09E19C58634218BF79DDFFCFD0D4C" xlink:to="loc_us-gaap_PlanNameDomain_8B591AD362C9940C78B49DDFFCFD65E1" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanTwoThousandEighteenInducementPlanMember" xlink:label="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanTwoThousandEighteenInducementPlanMember_BA8076EA5F0AB6F026BD9DDFFCFD49DC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_8B591AD362C9940C78B49DDFFCFD65E1" xlink:to="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanTwoThousandEighteenInducementPlanMember_BA8076EA5F0AB6F026BD9DDFFCFD49DC" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanMember" xlink:label="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanMember_C41030E25DBA4144D6819DDFFCFED6FF" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_8B591AD362C9940C78B49DDFFCFD65E1" xlink:to="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanMember_C41030E25DBA4144D6819DDFFCFED6FF" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_TwoThousandEighteenInducementPlanMember" xlink:label="loc_vlrx_TwoThousandEighteenInducementPlanMember_55D033350C04234313439DDFFCFEC479" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_8B591AD362C9940C78B49DDFFCFD65E1" xlink:to="loc_vlrx_TwoThousandEighteenInducementPlanMember_55D033350C04234313439DDFFCFEC479" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_PurchaseAgreementMember" xlink:label="loc_vlrx_PurchaseAgreementMember_77C5B1DE7E15B30914EA9DDFFCFED475" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_8B591AD362C9940C78B49DDFFCFD65E1" xlink:to="loc_vlrx_PurchaseAgreementMember_77C5B1DE7E15B30914EA9DDFFCFED475" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_AtMarketIssuanceSalesAgreementMember" xlink:label="loc_vlrx_AtMarketIssuanceSalesAgreementMember_C5DC86F4850703B5D52C9DDFFCFE2986" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_8B591AD362C9940C78B49DDFFCFD65E1" xlink:to="loc_vlrx_AtMarketIssuanceSalesAgreementMember_C5DC86F4850703B5D52C9DDFFCFE2986" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SecondPurchaseAgreementMember" xlink:label="loc_vlrx_SecondPurchaseAgreementMember_0D4E8FBAE61314B7E9EE9DDFFCFECECC" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_8B591AD362C9940C78B49DDFFCFD65E1" xlink:to="loc_vlrx_SecondPurchaseAgreementMember_0D4E8FBAE61314B7E9EE9DDFFCFECECC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="loc_srt_RangeAxis_9FB794279614A171A6639DDFFCFE36BF" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:to="loc_srt_RangeAxis_9FB794279614A171A6639DDFFCFE36BF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_1461732C9A89D1DFC5ED9DDFFCFFD8AC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RangeAxis_9FB794279614A171A6639DDFFCFE36BF" xlink:to="loc_srt_RangeMember_1461732C9A89D1DFC5ED9DDFFCFFD8AC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="loc_srt_MaximumMember_1959567A68BE3BA4809E9DDFFCFF8DCA" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RangeMember_1461732C9A89D1DFC5ED9DDFFCFFD8AC" xlink:to="loc_srt_MaximumMember_1959567A68BE3BA4809E9DDFFCFF8DCA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MinimumMember" xlink:label="loc_srt_MinimumMember_801ADDA48F990113FBEE9DDFFCFFDCCA" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RangeMember_1461732C9A89D1DFC5ED9DDFFCFFD8AC" xlink:to="loc_srt_MinimumMember_801ADDA48F990113FBEE9DDFFCFFDCCA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightAxis" xlink:label="loc_us-gaap_ClassOfWarrantOrRightAxis_277153F1BFC103A46C419DDFFCFFC6A8" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:to="loc_us-gaap_ClassOfWarrantOrRightAxis_277153F1BFC103A46C419DDFFCFFC6A8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightDomain" xlink:label="loc_us-gaap_ClassOfWarrantOrRightDomain_B099C393951D36B8CBC79DDFFD00BCD0" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightAxis_277153F1BFC103A46C419DDFFCFFC6A8" xlink:to="loc_us-gaap_ClassOfWarrantOrRightDomain_B099C393951D36B8CBC79DDFFD00BCD0" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SeriesAWarrantsMember" xlink:label="loc_vlrx_SeriesAWarrantsMember_5D11D4ACF66F8425A6F09DDFFD00E119" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightDomain_B099C393951D36B8CBC79DDFFD00BCD0" xlink:to="loc_vlrx_SeriesAWarrantsMember_5D11D4ACF66F8425A6F09DDFFD00E119" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SeriesBWarrantsMember" xlink:label="loc_vlrx_SeriesBWarrantsMember_B479DC93991DBECB13FD9DDFFD0087E3" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightDomain_B099C393951D36B8CBC79DDFFD00BCD0" xlink:to="loc_vlrx_SeriesBWarrantsMember_B479DC93991DBECB13FD9DDFFD0087E3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfStockLineItems" xlink:label="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:type="locator" />
    <link:presentationArc order="13" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_B55AF405DA3EE8528D879DDFFCF5BA78" xlink:to="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_9FAC4EB91D91B9EDD3ED9DDFFD001EAD" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_9FAC4EB91D91B9EDD3ED9DDFFD001EAD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_562A87E82052BF32CB4C9DDFFD017443" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_562A87E82052BF32CB4C9DDFFD017443" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_F55D0402D933C7F4E2059DDFFD013069" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_PreferredStockSharesAuthorized_F55D0402D933C7F4E2059DDFFD013069" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_74324464B83434CD3E669DDFFD0126D7" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_74324464B83434CD3E669DDFFD0126D7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharePrice" xlink:label="loc_us-gaap_SharePrice_10B3D51B687127D0FFBB9DDFFD01D580" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_SharePrice_10B3D51B687127D0FFBB9DDFFD01D580" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_10168B181D80F3184F0B9DDFFD014987" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_10168B181D80F3184F0B9DDFFD014987" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtConversionOriginalDebtAmount1" xlink:label="loc_us-gaap_DebtConversionOriginalDebtAmount1_30CE18277D0DB6B0151A9DDFFD01C6CC" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_DebtConversionOriginalDebtAmount1_30CE18277D0DB6B0151A9DDFFD01C6CC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtConversionConvertedInstrumentSharesIssued1" xlink:label="loc_us-gaap_DebtConversionConvertedInstrumentSharesIssued1_89E52D760993E01AFCF39DDFFD02C02A" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_DebtConversionConvertedInstrumentSharesIssued1_89E52D760993E01AFCF39DDFFD02C02A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockSharesSubscribedButUnissued" xlink:label="loc_us-gaap_CommonStockSharesSubscribedButUnissued_1EB8DAEBF72317C2EF9D9DDFFD02A3A9" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_CommonStockSharesSubscribedButUnissued_1EB8DAEBF72317C2EF9D9DDFFD02A3A9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockShareSubscribedButUnissuedSubscriptionsReceivable" xlink:label="loc_us-gaap_CommonStockShareSubscribedButUnissuedSubscriptionsReceivable_7532C91929F4F41857569DDFFD0210DA" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_CommonStockShareSubscribedButUnissuedSubscriptionsReceivable_7532C91929F4F41857569DDFFD0210DA" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CommonStockPurchaseAgreementTerm" xlink:label="loc_vlrx_CommonStockPurchaseAgreementTerm_AD544765AE1D6BA691959DDFFD02979F" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_vlrx_CommonStockPurchaseAgreementTerm_AD544765AE1D6BA691959DDFFD02979F" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CommonStockSubscriptionsReceivableMaximumSharesAuthorized" xlink:label="loc_vlrx_CommonStockSubscriptionsReceivableMaximumSharesAuthorized_4BD99940E82B9DF2C7469DDFFD024AC2" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_vlrx_CommonStockSubscriptionsReceivableMaximumSharesAuthorized_4BD99940E82B9DF2C7469DDFFD024AC2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:label="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_C7D1C90334364A2508AA9DDFFD02C600" xlink:type="locator" />
    <link:presentationArc order="13" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_C7D1C90334364A2508AA9DDFFD02C600" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CommonStockSharesAuthorizedLimitPercent" xlink:label="loc_vlrx_CommonStockSharesAuthorizedLimitPercent_1EBC2022ADD258B145C09DDFFD0377A7" xlink:type="locator" />
    <link:presentationArc order="14" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_vlrx_CommonStockSharesAuthorizedLimitPercent_1EBC2022ADD258B145C09DDFFD0377A7" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SaleofStockAveragePricePerShare" xlink:label="loc_vlrx_SaleofStockAveragePricePerShare_1548C52EE399C008053C9DDFFD036CD2" xlink:type="locator" />
    <link:presentationArc order="15" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_vlrx_SaleofStockAveragePricePerShare_1548C52EE399C008053C9DDFFD036CD2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_8A3DD30389499CA52BDE9DDFFD031105" xlink:type="locator" />
    <link:presentationArc order="16" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_8A3DD30389499CA52BDE9DDFFD031105" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentOfFinancingAndStockIssuanceCosts" xlink:label="loc_us-gaap_PaymentOfFinancingAndStockIssuanceCosts_6A55170C082197AFE1839DDFFD038F2E" xlink:type="locator" />
    <link:presentationArc order="17" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_PaymentOfFinancingAndStockIssuanceCosts_6A55170C082197AFE1839DDFFD038F2E" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_PaymentsOfOfferingCosts" xlink:label="loc_vlrx_PaymentsOfOfferingCosts_54497ED101EF38C7DE169DDFFD0331E1" xlink:type="locator" />
    <link:presentationArc order="18" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_vlrx_PaymentsOfOfferingCosts_54497ED101EF38C7DE169DDFFD0331E1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsOfStockIssuanceCosts" xlink:label="loc_us-gaap_PaymentsOfStockIssuanceCosts_79D83CD55C23C4D03AF19DDFFD037E12" xlink:type="locator" />
    <link:presentationArc order="19" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_PaymentsOfStockIssuanceCosts_79D83CD55C23C4D03AF19DDFFD037E12" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CommonStockSubscriptionsReceivablePurchaseSharesNoticeShares" xlink:label="loc_vlrx_CommonStockSubscriptionsReceivablePurchaseSharesNoticeShares_C71230C7A77E16773C9C9DDFFD0313E5" xlink:type="locator" />
    <link:presentationArc order="20" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_vlrx_CommonStockSubscriptionsReceivablePurchaseSharesNoticeShares_C71230C7A77E16773C9C9DDFFD0313E5" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CommonStockSubscriptionsReceivableConsiderationShares" xlink:label="loc_vlrx_CommonStockSubscriptionsReceivableConsiderationShares_FE824E6E838069550D629DDFFD04B86C" xlink:type="locator" />
    <link:presentationArc order="21" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_vlrx_CommonStockSubscriptionsReceivableConsiderationShares_FE824E6E838069550D629DDFFD04B86C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockPricePerShare" xlink:label="loc_us-gaap_SaleOfStockPricePerShare_263CC894520722D3671E9DDFFD04A7BA" xlink:type="locator" />
    <link:presentationArc order="22" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_SaleOfStockPricePerShare_263CC894520722D3671E9DDFFD04A7BA" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassOfWarrantOrRightIssued" xlink:label="loc_vlrx_ClassOfWarrantOrRightIssued_7E091018430B258474D69DDFFD04A4DF" xlink:type="locator" />
    <link:presentationArc order="23" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_vlrx_ClassOfWarrantOrRightIssued_7E091018430B258474D69DDFFD04A4DF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockConsiderationReceivedPerTransaction" xlink:label="loc_us-gaap_SaleOfStockConsiderationReceivedPerTransaction_236C899A6ED0D93C88F09DDFFD047AC9" xlink:type="locator" />
    <link:presentationArc order="24" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_SaleOfStockConsiderationReceivedPerTransaction_236C899A6ED0D93C88F09DDFFD047AC9" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsIssued" xlink:label="loc_vlrx_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsIssued_57E3D0093E8BEB5F9CBB9DDFFD040684" xlink:type="locator" />
    <link:presentationArc order="25" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_vlrx_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsIssued_57E3D0093E8BEB5F9CBB9DDFFD040684" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_WarrantsAndRightsOutstandingTerm" xlink:label="loc_us-gaap_WarrantsAndRightsOutstandingTerm_1EF98D4E8C483C8B3A079DDFFD05FE73" xlink:type="locator" />
    <link:presentationArc order="26" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_WarrantsAndRightsOutstandingTerm_1EF98D4E8C483C8B3A079DDFFD05FE73" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassOfRightOrWarrantExercisedInPeriod" xlink:label="loc_vlrx_ClassOfRightOrWarrantExercisedInPeriod_07EC59E4742E0BE1A1D09DDFFD05B850" xlink:type="locator" />
    <link:presentationArc order="27" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_vlrx_ClassOfRightOrWarrantExercisedInPeriod_07EC59E4742E0BE1A1D09DDFFD05B850" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion" xlink:label="loc_us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion_AA67697CDBC82F3F8CA39DDFFD058F5E" xlink:type="locator" />
    <link:presentationArc order="28" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion_AA67697CDBC82F3F8CA39DDFFD058F5E" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_AverageMarketCapitalizationConversionThreshold" xlink:label="loc_vlrx_AverageMarketCapitalizationConversionThreshold_6A560A216FC03BF30F069DDFFD05DE67" xlink:type="locator" />
    <link:presentationArc order="29" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_vlrx_AverageMarketCapitalizationConversionThreshold_6A560A216FC03BF30F069DDFFD05DE67" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_PreferredStockDividendRatePerOneHundredDollarsOfStock" xlink:label="loc_vlrx_PreferredStockDividendRatePerOneHundredDollarsOfStock_B998705C81892FEE57B59DDFFD0559FE" xlink:type="locator" />
    <link:presentationArc order="30" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_7EFFE7E1C156AEFD80B89DDFFD0070A6" xlink:to="loc_vlrx_PreferredStockDividendRatePerOneHundredDollarsOfStock_B998705C81892FEE57B59DDFFD0559FE" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/StockholdersEquityDeficitScheduleOfKeyAssumptionsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityAbstract" xlink:label="loc_us-gaap_EquityAbstract_20C85D3BC8D2553859A48F32F3CD98D3" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_EED5F7EF16DACB95DA808F32F3CE0D1D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityAbstract_20C85D3BC8D2553859A48F32F3CD98D3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_EED5F7EF16DACB95DA808F32F3CE0D1D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_7672908FD225E872CCE78F32F3CE1A5A" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityAbstract_20C85D3BC8D2553859A48F32F3CD98D3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_7672908FD225E872CCE78F32F3CE1A5A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_73DF571B6B40E91BACAF8F32F3CE956F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityAbstract_20C85D3BC8D2553859A48F32F3CD98D3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_73DF571B6B40E91BACAF8F32F3CE956F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_1CB44D78760A8621E1BA8F32F3CEF5EB" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityAbstract_20C85D3BC8D2553859A48F32F3CD98D3" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_1CB44D78760A8621E1BA8F32F3CEF5EB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_F295512E77EF91FCD1058F32F3CFD828" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityAbstract_20C85D3BC8D2553859A48F32F3CD98D3" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_F295512E77EF91FCD1058F32F3CFD828" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/StockholdersEquityDeficitScheduleOfStockOptionActivityDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityAbstract" xlink:label="loc_us-gaap_EquityAbstract_4EE55ABF9EA942062DD97F16A714B0C5" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_1BF5F2843C159BC3976A7F16A714C390" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityAbstract_4EE55ABF9EA942062DD97F16A714B0C5" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_1BF5F2843C159BC3976A7F16A714C390" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaap_PlanNameAxis_42A8CAEA47F36042D9737F16A714E91A" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_1BF5F2843C159BC3976A7F16A714C390" xlink:to="loc_us-gaap_PlanNameAxis_42A8CAEA47F36042D9737F16A714E91A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaap_PlanNameDomain_88E586335AB177DD7DAC7F16A715007D" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameAxis_42A8CAEA47F36042D9737F16A714E91A" xlink:to="loc_us-gaap_PlanNameDomain_88E586335AB177DD7DAC7F16A715007D" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanTwoThousandEighteenInducementPlanMember" xlink:label="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanTwoThousandEighteenInducementPlanMember_D4147C9F53610F45746A7F16A715CF18" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_88E586335AB177DD7DAC7F16A715007D" xlink:to="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanTwoThousandEighteenInducementPlanMember_D4147C9F53610F45746A7F16A715CF18" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_14ABA6BC68631AD0A4147F16A715390B" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_1BF5F2843C159BC3976A7F16A714C390" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_14ABA6BC68631AD0A4147F16A715390B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_96DAD51076A9100D44867F16A7154B0C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_14ABA6BC68631AD0A4147F16A715390B" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_96DAD51076A9100D44867F16A7154B0C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_D77CB7E4EFE7741A85D77F16A716EE87" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_96DAD51076A9100D44867F16A7154B0C" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_D77CB7E4EFE7741A85D77F16A716EE87" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_0D4A8B3864EFE98B8F717F16A716B43D" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_96DAD51076A9100D44867F16A7154B0C" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_0D4A8B3864EFE98B8F717F16A716B43D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_4F2BB7731CF906DEA17D7F16A716AE7A" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2009/role/negatedLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_96DAD51076A9100D44867F16A7154B0C" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_4F2BB7731CF906DEA17D7F16A716AE7A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_078149F8F38749BC20267F16A7164500" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_96DAD51076A9100D44867F16A7154B0C" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_078149F8F38749BC20267F16A7164500" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_1412105FB99FBE24DACC7F16A7160F67" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_14ABA6BC68631AD0A4147F16A715390B" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_1412105FB99FBE24DACC7F16A7160F67" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_B454414D5339BE1C3DDF7F16A7169431" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_14ABA6BC68631AD0A4147F16A715390B" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_B454414D5339BE1C3DDF7F16A7169431" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_289D8E2F8D58A83B26877F16A717552C" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_B454414D5339BE1C3DDF7F16A7169431" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_289D8E2F8D58A83B26877F16A717552C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_97F8D5E8930121E9B2D77F16A717B437" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_B454414D5339BE1C3DDF7F16A7169431" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_97F8D5E8930121E9B2D77F16A717B437" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_09CE65F7B0A09FD9ACA07F16A71779E2" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_B454414D5339BE1C3DDF7F16A7169431" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_09CE65F7B0A09FD9ACA07F16A71779E2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_967F62E8900D9D6EE4F97F16A7176EA9" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_B454414D5339BE1C3DDF7F16A7169431" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_967F62E8900D9D6EE4F97F16A7176EA9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageGrantDateFairValue_C4139DBA19AB78DA28DE7F16A71767B7" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_14ABA6BC68631AD0A4147F16A715390B" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageGrantDateFairValue_C4139DBA19AB78DA28DE7F16A71767B7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_5C9FA21345FE1B777EF87F16A718914B" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_14ABA6BC68631AD0A4147F16A715390B" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_5C9FA21345FE1B777EF87F16A718914B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_3CAC21921090437166CC7F16A7189B45" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_5C9FA21345FE1B777EF87F16A718914B" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_3CAC21921090437166CC7F16A7189B45" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsGrantedWeightedAverageRemainingContractualTerm" xlink:label="loc_vlrx_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsGrantedWeightedAverageRemainingContractualTerm_FF3E0A97BB4C23168A2D7F16A71876BF" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAdditionalDisclosuresAbstract_5C9FA21345FE1B777EF87F16A718914B" xlink:to="loc_vlrx_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsGrantedWeightedAverageRemainingContractualTerm_FF3E0A97BB4C23168A2D7F16A71876BF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1_CBBE5083700D5BFC691D7F16A71886DD" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_14ABA6BC68631AD0A4147F16A715390B" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1_CBBE5083700D5BFC691D7F16A71886DD" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsAggregateIntrinsicValueAbstract" xlink:label="loc_vlrx_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_6FBB522AB7F75B79EF1A7F16A71887F5" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_14ABA6BC68631AD0A4147F16A715390B" xlink:to="loc_vlrx_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_6FBB522AB7F75B79EF1A7F16A71887F5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_490D07B7FB654F89588C7F16A71861E9" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_6FBB522AB7F75B79EF1A7F16A71887F5" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_490D07B7FB654F89588C7F16A71861E9" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsGrantedIntrinsicValue" xlink:label="loc_vlrx_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsGrantedIntrinsicValue_8C1687A7913FDE5F29657F16A7192B96" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsAggregateIntrinsicValueAbstract_6FBB522AB7F75B79EF1A7F16A71887F5" xlink:to="loc_vlrx_SharebasedCompensationArrangementbySharebasedPaymentAwardOptionsGrantedIntrinsicValue_8C1687A7913FDE5F29657F16A7192B96" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_8A8DBC292EA8809C25E27F16A7194593" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_14ABA6BC68631AD0A4147F16A715390B" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_8A8DBC292EA8809C25E27F16A7194593" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/StockholdersEquityDeficitStockOptionsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityAbstract" xlink:label="loc_us-gaap_EquityAbstract_CB4AA8523E8D24DE212B985668923F11" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_22C9C37C773B71D76A6198566893A0BD" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityAbstract_CB4AA8523E8D24DE212B985668923F11" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_22C9C37C773B71D76A6198566893A0BD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaap_PlanNameAxis_813EA16A7D29BCE63D909856689397F0" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_22C9C37C773B71D76A6198566893A0BD" xlink:to="loc_us-gaap_PlanNameAxis_813EA16A7D29BCE63D909856689397F0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaap_PlanNameDomain_A867DACB95C647CB7E1498566894100B" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameAxis_813EA16A7D29BCE63D909856689397F0" xlink:to="loc_us-gaap_PlanNameDomain_A867DACB95C647CB7E1498566894100B" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanMember" xlink:label="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanMember_41AAE9FADDBA3343570C98566895A62E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_A867DACB95C647CB7E1498566894100B" xlink:to="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanMember_41AAE9FADDBA3343570C98566895A62E" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanTwoThousandEighteenInducementPlanMember" xlink:label="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanTwoThousandEighteenInducementPlanMember_8676545C3048B6BFA6A5985668951142" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_A867DACB95C647CB7E1498566894100B" xlink:to="loc_vlrx_TwoThousandSixteenEmployeeEquityCompensationPlanTwoThousandEighteenInducementPlanMember_8676545C3048B6BFA6A5985668951142" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4E9012F1E8D9BDA5780998566896EC03" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_22C9C37C773B71D76A6198566893A0BD" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4E9012F1E8D9BDA5780998566896EC03" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCost1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCost1_0DED322F924B5951358D985668962CE6" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4E9012F1E8D9BDA5780998566896EC03" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardCompensationCost1_0DED322F924B5951358D985668962CE6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_FCDFD3812280F8C18FB1985668973CC7" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4E9012F1E8D9BDA5780998566896EC03" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_FCDFD3812280F8C18FB1985668973CC7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1_98375EFFC3F5586F075D98566897EBA6" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4E9012F1E8D9BDA5780998566896EC03" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1_98375EFFC3F5586F075D98566897EBA6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_BFEB80175F77119422CE989845F5BD5D" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4E9012F1E8D9BDA5780998566896EC03" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_BFEB80175F77119422CE989845F5BD5D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_E669C7264CB70ACF852998566898E3E0" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4E9012F1E8D9BDA5780998566896EC03" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions_E669C7264CB70ACF852998566898E3E0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_2607F15F7301325F394298566898AC99" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_4E9012F1E8D9BDA5780998566896EC03" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_2607F15F7301325F394298566898AC99" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/StockholdersEquityDeficitTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityAbstract" xlink:label="loc_us-gaap_EquityAbstract_23EB12D0154D8D3373C57F16A74AF6FE" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_71104F16FBD8977613177F16A74AF943" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityAbstract_23EB12D0154D8D3373C57F16A74AF6FE" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock_71104F16FBD8977613177F16A74AF943" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_F88A0E2B8CE199BC8B037F16A74B1912" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_EquityAbstract_23EB12D0154D8D3373C57F16A74AF6FE" xlink:to="loc_us-gaap_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsTableTextBlock_F88A0E2B8CE199BC8B037F16A74B1912" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/SubsequentEvents" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventsAbstract" xlink:label="loc_us-gaap_SubsequentEventsAbstract_930B3FA8F5A8EA86857D60E64D3651DA" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsequentEventsTextBlock" xlink:label="loc_us-gaap_SubsequentEventsTextBlock_FB841CBF8D91E4A39AD460E64D369335" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsequentEventsAbstract_930B3FA8F5A8EA86857D60E64D3651DA" xlink:to="loc_us-gaap_SubsequentEventsTextBlock_FB841CBF8D91E4A39AD460E64D369335" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/UncertaintiesLiquidityAndAbilityToContinueAsGoingConcern" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:label="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_0E5263BBC7C265214AB57B2000BC9F52" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubstantialDoubtAboutGoingConcernTextBlock" xlink:label="loc_us-gaap_SubstantialDoubtAboutGoingConcernTextBlock_EF753034AAA28A9D3FCE7B2000BC5CF2" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_0E5263BBC7C265214AB57B2000BC9F52" xlink:to="loc_us-gaap_SubstantialDoubtAboutGoingConcernTextBlock_EF753034AAA28A9D3FCE7B2000BC5CF2" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/UncertaintiesLiquidityAndAbilityToContinueAsGoingConcernDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:label="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_E35B71BE02B23BD0FCBB9E44712737BD" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfStockByClassTable" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_024712D93A51CF750B249E4471270549" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_E35B71BE02B23BD0FCBB9E44712737BD" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_024712D93A51CF750B249E4471270549" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_CounterpartyNameAxis" xlink:label="loc_srt_CounterpartyNameAxis_27014F6F8508A01057DC9E44712770CC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_024712D93A51CF750B249E4471270549" xlink:to="loc_srt_CounterpartyNameAxis_27014F6F8508A01057DC9E44712770CC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_0B6ABC73245B02E641949E4471289516" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_CounterpartyNameAxis_27014F6F8508A01057DC9E44712770CC" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_0B6ABC73245B02E641949E4471289516" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_AspireCapitalFundLLCMember" xlink:label="loc_vlrx_AspireCapitalFundLLCMember_2CCDF5A6BC1F37F5720F9E4471287EB7" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_0B6ABC73245B02E641949E4471289516" xlink:to="loc_vlrx_AspireCapitalFundLLCMember_2CCDF5A6BC1F37F5720F9E4471287EB7" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_B.RileyFBRInc.Member" xlink:label="loc_vlrx_B.RileyFBRInc.Member_FBFB304469F5C42A25CB9E447128B14D" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_0B6ABC73245B02E641949E4471289516" xlink:to="loc_vlrx_B.RileyFBRInc.Member_FBFB304469F5C42A25CB9E447128B14D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaap_PlanNameAxis_568C8CC2943173C6CAF89E44712831B6" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_024712D93A51CF750B249E4471270549" xlink:to="loc_us-gaap_PlanNameAxis_568C8CC2943173C6CAF89E44712831B6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaap_PlanNameDomain_869A0338866B18F0FA1E9E447128E934" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameAxis_568C8CC2943173C6CAF89E44712831B6" xlink:to="loc_us-gaap_PlanNameDomain_869A0338866B18F0FA1E9E447128E934" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_AtMarketIssuanceSalesAgreementMember" xlink:label="loc_vlrx_AtMarketIssuanceSalesAgreementMember_92981EDCEBC82B41B12F9E447129D685" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_869A0338866B18F0FA1E9E447128E934" xlink:to="loc_vlrx_AtMarketIssuanceSalesAgreementMember_92981EDCEBC82B41B12F9E447129D685" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SecondPurchaseAgreementMember" xlink:label="loc_vlrx_SecondPurchaseAgreementMember_2128D36EB7C2DDB761899E447129FB26" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_PlanNameDomain_869A0338866B18F0FA1E9E447128E934" xlink:to="loc_vlrx_SecondPurchaseAgreementMember_2128D36EB7C2DDB761899E447129FB26" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis_9F887F46CC31147683439E4471294D08" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_024712D93A51CF750B249E4471270549" xlink:to="loc_us-gaap_SubsidiarySaleOfStockAxis_9F887F46CC31147683439E4471294D08" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_C0E2117F42FB50E3B5FA9E4471293D54" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_9F887F46CC31147683439E4471294D08" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_C0E2117F42FB50E3B5FA9E4471293D54" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="loc_srt_RangeAxis_D409141999769CD4DD929E44712978EA" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_024712D93A51CF750B249E4471270549" xlink:to="loc_srt_RangeAxis_D409141999769CD4DD929E44712978EA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_95E109940E6EA840662C9E4471293353" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RangeAxis_D409141999769CD4DD929E44712978EA" xlink:to="loc_srt_RangeMember_95E109940E6EA840662C9E4471293353" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MinimumMember" xlink:label="loc_srt_MinimumMember_A554E449F38834F5D7BD9E4471291EDA" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RangeMember_95E109940E6EA840662C9E4471293353" xlink:to="loc_srt_MinimumMember_A554E449F38834F5D7BD9E4471291EDA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="loc_srt_MaximumMember_1CB9EFAFB315BA8AD8479E4471299847" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_srt_RangeMember_95E109940E6EA840662C9E4471293353" xlink:to="loc_srt_MaximumMember_1CB9EFAFB315BA8AD8479E4471299847" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightAxis" xlink:label="loc_us-gaap_ClassOfWarrantOrRightAxis_9FEEF200C5D1468962C19E44712A4672" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_024712D93A51CF750B249E4471270549" xlink:to="loc_us-gaap_ClassOfWarrantOrRightAxis_9FEEF200C5D1468962C19E44712A4672" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightDomain" xlink:label="loc_us-gaap_ClassOfWarrantOrRightDomain_2E817C1AB9F7FC7EDD2D9E44712A3F0E" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightAxis_9FEEF200C5D1468962C19E44712A4672" xlink:to="loc_us-gaap_ClassOfWarrantOrRightDomain_2E817C1AB9F7FC7EDD2D9E44712A3F0E" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SeriesAWarrantsMember" xlink:label="loc_vlrx_SeriesAWarrantsMember_9C1BA592FDA47EE7C0559E44712A3892" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightDomain_2E817C1AB9F7FC7EDD2D9E44712A3F0E" xlink:to="loc_vlrx_SeriesAWarrantsMember_9C1BA592FDA47EE7C0559E44712A3892" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SeriesBWarrantsMember" xlink:label="loc_vlrx_SeriesBWarrantsMember_BD57CF8F510605F9346D9E44712AE7B2" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightDomain_2E817C1AB9F7FC7EDD2D9E44712A3F0E" xlink:to="loc_vlrx_SeriesBWarrantsMember_BD57CF8F510605F9346D9E44712AE7B2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfStockLineItems" xlink:label="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_024712D93A51CF750B249E4471270549" xlink:to="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_D70CAD180FABBC9657D69E44712BF699" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_D70CAD180FABBC9657D69E44712BF699" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestrictedCash" xlink:label="loc_us-gaap_RestrictedCash_07118EF0B34F44C1D8569E44712BD36A" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_us-gaap_RestrictedCash_07118EF0B34F44C1D8569E44712BD36A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_F43130805B8484BFA7809E44712B8B3E" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_F43130805B8484BFA7809E44712B8B3E" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CommonStockSubscriptionsReceivablePurchaseSharesNoticeShares" xlink:label="loc_vlrx_CommonStockSubscriptionsReceivablePurchaseSharesNoticeShares_75F6A8DD5C77513712C39E44712B865E" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_vlrx_CommonStockSubscriptionsReceivablePurchaseSharesNoticeShares_75F6A8DD5C77513712C39E44712B865E" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_DebtInstrumentCovenantMinimumCashAndCashEquivalents" xlink:label="loc_vlrx_DebtInstrumentCovenantMinimumCashAndCashEquivalents_05E6B8B5A08AA90FE8419E44712B2D0B" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_vlrx_DebtInstrumentCovenantMinimumCashAndCashEquivalents_05E6B8B5A08AA90FE8419E44712B2D0B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockShareSubscribedButUnissuedSubscriptionsReceivable" xlink:label="loc_us-gaap_CommonStockShareSubscribedButUnissuedSubscriptionsReceivable_A6F8FE37DB471868A3029E44712B9756" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_us-gaap_CommonStockShareSubscribedButUnissuedSubscriptionsReceivable_A6F8FE37DB471868A3029E44712B9756" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:label="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_6753BA53C71F09390DC59E44712CB799" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_6753BA53C71F09390DC59E44712CB799" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_08C43169C1FDC928A8DA9E44712CAD97" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues_08C43169C1FDC928A8DA9E44712CAD97" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_10BAAE9E230AD3BC578D9E44712CE42B" xlink:type="locator" />
    <link:presentationArc order="9" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues_10BAAE9E230AD3BC578D9E44712CE42B" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SaleofStockAveragePricePerShare" xlink:label="loc_vlrx_SaleofStockAveragePricePerShare_A2BDEB16D51B8382B22E9E44712CDBA8" xlink:type="locator" />
    <link:presentationArc order="10" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_vlrx_SaleofStockAveragePricePerShare_A2BDEB16D51B8382B22E9E44712CDBA8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentOfFinancingAndStockIssuanceCosts" xlink:label="loc_us-gaap_PaymentOfFinancingAndStockIssuanceCosts_37772534191F5B523C809E44712C0F62" xlink:type="locator" />
    <link:presentationArc order="11" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_us-gaap_PaymentOfFinancingAndStockIssuanceCosts_37772534191F5B523C809E44712C0F62" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_PaymentsOfOfferingCosts" xlink:label="loc_vlrx_PaymentsOfOfferingCosts_C60A4B237D6F2201EAE59E44712D0687" xlink:type="locator" />
    <link:presentationArc order="12" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_vlrx_PaymentsOfOfferingCosts_C60A4B237D6F2201EAE59E44712D0687" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CommonStockSubscriptionsReceivableMaximumSharesAuthorized" xlink:label="loc_vlrx_CommonStockSubscriptionsReceivableMaximumSharesAuthorized_D47094403B23EEC4E2949E44712DB35A" xlink:type="locator" />
    <link:presentationArc order="13" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_vlrx_CommonStockSubscriptionsReceivableMaximumSharesAuthorized_D47094403B23EEC4E2949E44712DB35A" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CommonStockSharesAuthorizedLimitPercent" xlink:label="loc_vlrx_CommonStockSharesAuthorizedLimitPercent_F17B4CA8A7AA62FD1A2E9E44712DC2F6" xlink:type="locator" />
    <link:presentationArc order="14" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_vlrx_CommonStockSharesAuthorizedLimitPercent_F17B4CA8A7AA62FD1A2E9E44712DC2F6" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SaleofStockMinimumPricePerShare" xlink:label="loc_vlrx_SaleofStockMinimumPricePerShare_1930EF14B7BDF99A5C9A9E44712D282D" xlink:type="locator" />
    <link:presentationArc order="15" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_vlrx_SaleofStockMinimumPricePerShare_1930EF14B7BDF99A5C9A9E44712D282D" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_CommonStockSubscriptionsReceivableConsiderationShares" xlink:label="loc_vlrx_CommonStockSubscriptionsReceivableConsiderationShares_19492519A7C2B1C373AE9E44712D6311" xlink:type="locator" />
    <link:presentationArc order="16" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_vlrx_CommonStockSubscriptionsReceivableConsiderationShares_19492519A7C2B1C373AE9E44712D6311" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockConsiderationReceivedPerTransaction" xlink:label="loc_us-gaap_SaleOfStockConsiderationReceivedPerTransaction_51D04EE420C7B599616E9E44712D29D9" xlink:type="locator" />
    <link:presentationArc order="17" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_us-gaap_SaleOfStockConsiderationReceivedPerTransaction_51D04EE420C7B599616E9E44712D29D9" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassOfWarrantOrRightIssued" xlink:label="loc_vlrx_ClassOfWarrantOrRightIssued_7F96863DF6DC76FC1CB49E44712E012A" xlink:type="locator" />
    <link:presentationArc order="18" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_vlrx_ClassOfWarrantOrRightIssued_7F96863DF6DC76FC1CB49E44712E012A" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsIssued" xlink:label="loc_vlrx_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsIssued_0982FE1FE5200D8F85009E44712E3C17" xlink:type="locator" />
    <link:presentationArc order="19" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_vlrx_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsIssued_0982FE1FE5200D8F85009E44712E3C17" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassesOrWarrantRightExercisablePeriod" xlink:label="loc_vlrx_ClassesOrWarrantRightExercisablePeriod_F1435AFC4EA55CF805329E44712E4CBD" xlink:type="locator" />
    <link:presentationArc order="20" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_vlrx_ClassesOrWarrantRightExercisablePeriod_F1435AFC4EA55CF805329E44712E4CBD" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassofWarrantorRightEstimatedRevenueBeforeFees" xlink:label="loc_vlrx_ClassofWarrantorRightEstimatedRevenueBeforeFees_F7B3E646CA50E2212FA29E44712E859B" xlink:type="locator" />
    <link:presentationArc order="21" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_vlrx_ClassofWarrantorRightEstimatedRevenueBeforeFees_F7B3E646CA50E2212FA29E44712E859B" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassOfRightOrWarrantExercisedInPeriod" xlink:label="loc_vlrx_ClassOfRightOrWarrantExercisedInPeriod_EDE3BED9367E857259D29E44712EADA0" xlink:type="locator" />
    <link:presentationArc order="22" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_vlrx_ClassOfRightOrWarrantExercisedInPeriod_EDE3BED9367E857259D29E44712EADA0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" xlink:label="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_CD80A476ED0641FB6FDA9E44712E7BF6" xlink:type="locator" />
    <link:presentationArc order="23" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfStockLineItems_CDCCF2EB4DDECA0AF8FC9E44712A14F9" xlink:to="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_CD80A476ED0641FB6FDA9E44712E7BF6" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/Warrants" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_5A4BBB41AF0A9DC6859752DB8EED7E48" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock_E34537BDACBDF53ABEAD52DB8EED0B67" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_5A4BBB41AF0A9DC6859752DB8EED7E48" xlink:to="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureTextBlock_E34537BDACBDF53ABEAD52DB8EED0B67" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/WarrantsAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_0FA2B7B0192F997AAFB5996209A59D37" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_41E8BBC89277442B9B5F996209A6B0D8" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_0FA2B7B0192F997AAFB5996209A59D37" xlink:to="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_41E8BBC89277442B9B5F996209A6B0D8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightAxis" xlink:label="loc_us-gaap_ClassOfWarrantOrRightAxis_7E8CC39F70A1515AE9DD996209A65A57" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_41E8BBC89277442B9B5F996209A6B0D8" xlink:to="loc_us-gaap_ClassOfWarrantOrRightAxis_7E8CC39F70A1515AE9DD996209A65A57" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightDomain" xlink:label="loc_us-gaap_ClassOfWarrantOrRightDomain_A916525B9251AC6F39D2996209A6C4C0" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightAxis_7E8CC39F70A1515AE9DD996209A65A57" xlink:to="loc_us-gaap_ClassOfWarrantOrRightDomain_A916525B9251AC6F39D2996209A6C4C0" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_PlacementAgentWarrantsMember" xlink:label="loc_vlrx_PlacementAgentWarrantsMember_5544D8BC5464C0ED3241996209A698C6" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightDomain_A916525B9251AC6F39D2996209A6C4C0" xlink:to="loc_vlrx_PlacementAgentWarrantsMember_5544D8BC5464C0ED3241996209A698C6" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SeriesAWarrantsMember" xlink:label="loc_vlrx_SeriesAWarrantsMember_321DE8143AA54BBB7B4E996209A777A6" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightDomain_A916525B9251AC6F39D2996209A6C4C0" xlink:to="loc_vlrx_SeriesAWarrantsMember_321DE8143AA54BBB7B4E996209A777A6" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_SeriesBWarrantsMember" xlink:label="loc_vlrx_SeriesBWarrantsMember_0B7BF78A289A289ED969996209A78C0F" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightDomain_A916525B9251AC6F39D2996209A6C4C0" xlink:to="loc_vlrx_SeriesBWarrantsMember_0B7BF78A289A289ED969996209A78C0F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_61322DABF990F34071F4996209A723D0" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_41E8BBC89277442B9B5F996209A6B0D8" xlink:to="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_61322DABF990F34071F4996209A723D0" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassOfWarrantOrRightIssued" xlink:label="loc_vlrx_ClassOfWarrantOrRightIssued_AC7EF6242EB86497FE70996209A7DB22" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_61322DABF990F34071F4996209A723D0" xlink:to="loc_vlrx_ClassOfWarrantOrRightIssued_AC7EF6242EB86497FE70996209A7DB22" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeTermOfContract" xlink:label="loc_us-gaap_DerivativeTermOfContract_F2C2C66C6D072D25600F996209A8F5D7" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_61322DABF990F34071F4996209A723D0" xlink:to="loc_us-gaap_DerivativeTermOfContract_F2C2C66C6D072D25600F996209A8F5D7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeLiabilitiesCurrent" xlink:label="loc_us-gaap_DerivativeLiabilitiesCurrent_5044E54B26DA5B51FA37996209A89F4E" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_61322DABF990F34071F4996209A723D0" xlink:to="loc_us-gaap_DerivativeLiabilitiesCurrent_5044E54B26DA5B51FA37996209A89F4E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockPricePerShare" xlink:label="loc_us-gaap_SaleOfStockPricePerShare_6E77F7CF82B50D265100996209A8AEC4" xlink:type="locator" />
    <link:presentationArc order="4" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_61322DABF990F34071F4996209A723D0" xlink:to="loc_us-gaap_SaleOfStockPricePerShare_6E77F7CF82B50D265100996209A8AEC4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SaleOfStockConsiderationReceivedPerTransaction" xlink:label="loc_us-gaap_SaleOfStockConsiderationReceivedPerTransaction_4A1F149B54183026717D996209A8D3AC" xlink:type="locator" />
    <link:presentationArc order="5" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_61322DABF990F34071F4996209A723D0" xlink:to="loc_us-gaap_SaleOfStockConsiderationReceivedPerTransaction_4A1F149B54183026717D996209A8D3AC" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsIssued" xlink:label="loc_vlrx_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsIssued_C7867A5CF49F86DBB917996209A86697" xlink:type="locator" />
    <link:presentationArc order="6" preferredLabel="http://www.xbrl.org/2003/role/verboseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_61322DABF990F34071F4996209A723D0" xlink:to="loc_vlrx_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsIssued_C7867A5CF49F86DBB917996209A86697" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassOfRightOrWarrantExercisedInPeriod" xlink:label="loc_vlrx_ClassOfRightOrWarrantExercisedInPeriod_A049EBD7ED7983BC2E08996209A92ED9" xlink:type="locator" />
    <link:presentationArc order="7" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_61322DABF990F34071F4996209A723D0" xlink:to="loc_vlrx_ClassOfRightOrWarrantExercisedInPeriod_A049EBD7ED7983BC2E08996209A92ED9" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassesOrWarrantRightExercisablePeriod" xlink:label="loc_vlrx_ClassesOrWarrantRightExercisablePeriod_A761C9A5D2D083E76BD9996209A946DD" xlink:type="locator" />
    <link:presentationArc order="8" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_61322DABF990F34071F4996209A723D0" xlink:to="loc_vlrx_ClassesOrWarrantRightExercisablePeriod_A761C9A5D2D083E76BD9996209A946DD" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/WarrantsScheduleOfActivitiesOfWarrantsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_F52DADB7B9B0637EBB257B9D1A0A75C8" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightTable" xlink:label="loc_us-gaap_ClassOfWarrantOrRightTable_6CA647921CB51DE6C7C27B9D1A0A9557" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_F52DADB7B9B0637EBB257B9D1A0A75C8" xlink:to="loc_us-gaap_ClassOfWarrantOrRightTable_6CA647921CB51DE6C7C27B9D1A0A9557" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightAxis" xlink:label="loc_us-gaap_ClassOfWarrantOrRightAxis_4F0A613EBCE559A92ABA7B9D1A0B88CA" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightTable_6CA647921CB51DE6C7C27B9D1A0A9557" xlink:to="loc_us-gaap_ClassOfWarrantOrRightAxis_4F0A613EBCE559A92ABA7B9D1A0B88CA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightDomain" xlink:label="loc_us-gaap_ClassOfWarrantOrRightDomain_4BDCF0BCF8BF70848D567B9D1A0B5C39" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightAxis_4F0A613EBCE559A92ABA7B9D1A0B88CA" xlink:to="loc_us-gaap_ClassOfWarrantOrRightDomain_4BDCF0BCF8BF70848D567B9D1A0B5C39" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_PlacementAgentWarrantsMember" xlink:label="loc_vlrx_PlacementAgentWarrantsMember_071A7A3C99586E88E03C7B9D1A0B8079" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightDomain_4BDCF0BCF8BF70848D567B9D1A0B5C39" xlink:to="loc_vlrx_PlacementAgentWarrantsMember_071A7A3C99586E88E03C7B9D1A0B8079" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_EquityClassifiedWarrantsMember" xlink:label="loc_vlrx_EquityClassifiedWarrantsMember_C461745DBD78FC34942E7B9D1A0B58EC" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightDomain_4BDCF0BCF8BF70848D567B9D1A0B5C39" xlink:to="loc_vlrx_EquityClassifiedWarrantsMember_C461745DBD78FC34942E7B9D1A0B58EC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ClassOfWarrantOrRightLineItems" xlink:label="loc_us-gaap_ClassOfWarrantOrRightLineItems_B2CDE7542EA21EBB3F3F7B9D1A0C1A55" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightTable_6CA647921CB51DE6C7C27B9D1A0A9557" xlink:to="loc_us-gaap_ClassOfWarrantOrRightLineItems_B2CDE7542EA21EBB3F3F7B9D1A0C1A55" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassofWarrantorRightWarrantsRollForwardRollForward" xlink:label="loc_vlrx_ClassofWarrantorRightWarrantsRollForwardRollForward_9AD525CF6BCA889214AB7B9D1A0C7139" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_B2CDE7542EA21EBB3F3F7B9D1A0C1A55" xlink:to="loc_vlrx_ClassofWarrantorRightWarrantsRollForwardRollForward_9AD525CF6BCA889214AB7B9D1A0C7139" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassofWarrantorRightOutstandingAndExercisable" xlink:label="loc_vlrx_ClassofWarrantorRightOutstandingAndExercisable_00E99723D16F883A8EC87B9D1A0C7B80" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_ClassofWarrantorRightWarrantsRollForwardRollForward_9AD525CF6BCA889214AB7B9D1A0C7139" xlink:to="loc_vlrx_ClassofWarrantorRightOutstandingAndExercisable_00E99723D16F883A8EC87B9D1A0C7B80" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassOfWarrantOrRightExercisesInPeriod" xlink:label="loc_vlrx_ClassOfWarrantOrRightExercisesInPeriod_1880E5ABA6849BFBCCCD7B9D1A0CAA05" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_ClassofWarrantorRightWarrantsRollForwardRollForward_9AD525CF6BCA889214AB7B9D1A0C7139" xlink:to="loc_vlrx_ClassOfWarrantOrRightExercisesInPeriod_1880E5ABA6849BFBCCCD7B9D1A0CAA05" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassofWarrantorRightOutstandingAndExercisable" xlink:label="loc_vlrx_ClassofWarrantorRightOutstandingAndExercisable_4B063E110A7E702788437B9D1A0D7F79" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_ClassofWarrantorRightWarrantsRollForwardRollForward_9AD525CF6BCA889214AB7B9D1A0C7139" xlink:to="loc_vlrx_ClassofWarrantorRightOutstandingAndExercisable_4B063E110A7E702788437B9D1A0D7F79" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassofWarrantorRightWarrantsWeightedAverageExercisePriceRollForward" xlink:label="loc_vlrx_ClassofWarrantorRightWarrantsWeightedAverageExercisePriceRollForward_C122F6500D58F2E621467B9D1A0DBB7A" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_B2CDE7542EA21EBB3F3F7B9D1A0C1A55" xlink:to="loc_vlrx_ClassofWarrantorRightWarrantsWeightedAverageExercisePriceRollForward_C122F6500D58F2E621467B9D1A0DBB7A" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassofWarrantorRightOutstandingAndExercisableWeightedAverageExercisePrice" xlink:label="loc_vlrx_ClassofWarrantorRightOutstandingAndExercisableWeightedAverageExercisePrice_5974BBC4D67712571D8D7B9D1A0D8BBD" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/periodStartLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_ClassofWarrantorRightWarrantsWeightedAverageExercisePriceRollForward_C122F6500D58F2E621467B9D1A0DBB7A" xlink:to="loc_vlrx_ClassofWarrantorRightOutstandingAndExercisableWeightedAverageExercisePrice_5974BBC4D67712571D8D7B9D1A0D8BBD" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsExercised" xlink:label="loc_vlrx_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsExercised_0D39ABBD70F860268A377B9D1A0E066A" xlink:type="locator" />
    <link:presentationArc order="2" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" priority="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_ClassofWarrantorRightWarrantsWeightedAverageExercisePriceRollForward_C122F6500D58F2E621467B9D1A0DBB7A" xlink:to="loc_vlrx_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsExercised_0D39ABBD70F860268A377B9D1A0E066A" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassofWarrantorRightOutstandingAndExercisableWeightedAverageExercisePrice" xlink:label="loc_vlrx_ClassofWarrantorRightOutstandingAndExercisableWeightedAverageExercisePrice_445EC00AB1F36AA1DD2A7B9D1A0E208B" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/periodEndLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_ClassofWarrantorRightWarrantsWeightedAverageExercisePriceRollForward_C122F6500D58F2E621467B9D1A0DBB7A" xlink:to="loc_vlrx_ClassofWarrantorRightOutstandingAndExercisableWeightedAverageExercisePrice_445EC00AB1F36AA1DD2A7B9D1A0E208B" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassofWarrantorRightWarrantsWeightedAverageRemainingContractualTermAbstract" xlink:label="loc_vlrx_ClassofWarrantorRightWarrantsWeightedAverageRemainingContractualTermAbstract_4FA493D434C5115CBC577B9D1A0E51E1" xlink:type="locator" />
    <link:presentationArc order="3" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_B2CDE7542EA21EBB3F3F7B9D1A0C1A55" xlink:to="loc_vlrx_ClassofWarrantorRightWarrantsWeightedAverageRemainingContractualTermAbstract_4FA493D434C5115CBC577B9D1A0E51E1" xlink:type="arc" />
    <link:loc xlink:href="vlrx-20190331.xsd#vlrx_ClassofWarrantorRightOutstandingandExercisableWeightedAverageRemainingContractualTerm" xlink:label="loc_vlrx_ClassofWarrantorRightOutstandingandExercisableWeightedAverageRemainingContractualTerm_D1818A2E03415E06E6047B9D1A0E591F" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_vlrx_ClassofWarrantorRightWarrantsWeightedAverageRemainingContractualTermAbstract_4FA493D434C5115CBC577B9D1A0E51E1" xlink:to="loc_vlrx_ClassofWarrantorRightOutstandingandExercisableWeightedAverageRemainingContractualTerm_D1818A2E03415E06E6047B9D1A0E591F" xlink:type="arc" />
  </link:presentationLink>
  <link:presentationLink xlink:role="http://imetrix.edgar-online.com/role/WarrantsTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_CF04E763F6CB7C8DA75C52DB8F3DD9B1" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock" xlink:label="loc_us-gaap_ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock_02767C4CCB0024886A4C52DB8F3E87EC" xlink:type="locator" />
    <link:presentationArc order="1" preferredLabel="http://www.xbrl.org/2003/role/terseLabel" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_CF04E763F6CB7C8DA75C52DB8F3DD9B1" xlink:to="loc_us-gaap_ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock_02767C4CCB0024886A4C52DB8F3E87EC" xlink:type="arc" />
  </link:presentationLink>
</link:linkbase>