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Lexeo Therapeutics Announces Progress in FDA Discussions for Accelerated Approval Pathway and Positive Interim Clinical Data for LX2006 in Friedreich Ataxia Cardiomyopathy
U.S. Food and Drug Administration (FDA) open to pooling data from ongoing Phase I/II studies of LX2006 with pivotal data to support a Biologics License Application (BLA) for Accelerated Approval
Interim clinical data show sustained or deepening improvements in the majority of participants across both
cardiac and neurologic measures of Friedreich ataxia
Participants with abnormal left ventricular mass index (LVMI) at baseline achieved 18% mean reduction in LVMI at 6 months and 23% mean reduction at 12 months, exceeding FDA-aligned target threshold of 10% reduction
Clinically meaningful improvement observed in the modified Friedreich Ataxia Rating Scale (mFARS), indicative of slowed disease progression and improved function
Company to host webcast today at 8:00 AM ET
NEW YORK – October 7, 2025 (GLOBE NEWSWIRE) – Lexeo Therapeutics, Inc. (Nasdaq: LXEO), a clinical stage genetic medicine company dedicated to pioneering novel treatments for cardiovascular diseases, today announced updates to key components of an Accelerated Approval pathway for LX2006 in Friedreich ataxia (FA) cardiomyopathy, alongside new interim clinical data from ongoing Phase I/II studies.
“We are encouraged by our recent dialogue with the FDA on LX2006, and we appreciate the Agency’s collaborative spirit as we work to deliver a potentially life-changing therapy to the FA community as efficiently as possible,” said R. Nolan Townsend, Chief Executive Officer of Lexeo Therapeutics. “Given the highly compelling data to date that demonstrate clinically meaningful improvements across both cardiac and neurologic measures of FA, we are now pursuing a development strategy that could enable a smaller pivotal study, given the potential to pool data with the ongoing Phase I/II trials, as well as potentially assessing the co-primary endpoint of LVMI earlier than 12 months. This approach could accelerate our overall timeline toward a BLA submission for LX2006 under the Accelerated Approval pathway.”
FDA Feedback to Date
In response to questions from the Company regarding the possibility of a faster path to a BLA, the FDA has indicated openness to a BLA submission for accelerated approval that includes clinical data from the ongoing Phase I/II studies of LX2006 pooled with new clinical data to be generated in the planned pivotal study. To enable pooling of these data to support licensure, Lexeo will submit enhanced manufacturing comparability data and meet an additional nonclinical requirement prior to the initiation of the planned pivotal study, given the Company’s intention to leverage its optimized, high-yield Sf9-baculovirus manufacturing platform for future clinical and commercial drug supply, compared to the adherent HEK293 process used for Phase I/II clinical supply. The FDA also previously agreed to evaluate the co-primary endpoint of LVMI at a time point earlier than 12 months. Lexeo continues to engage with the FDA on the pivotal protocol and comparability. In discussions to date, there have been no changes to the previously disclosed alignment with the FDA on key parameters related to the LX2006 planned registrational study.
Collectively, Lexeo believes this regulatory feedback has the potential to reduce the size and length of the planned pivotal study, possibly accelerating the overall timeline to BLA submission. Lexeo plans to initiate the LX2006 pivotal study as soon as possible in the first half of 2026, pending finalization of the trial protocol. FDA has previously granted Breakthrough Therapy, Regenerative Medicine Advanced Therapy (RMAT), Orphan Drug and Fast Track designations to LX2006, and admitted LX2006 into the CMC Development and Readiness Pilot (CDRP) program.