Consent of Independent Registered Public Accounting Firm
We consent to the incorporation by reference in the following Registration Statements:
1)
Registration Statement (Form S-8 No. 333-282106) pertaining to the MBX Biosciences, Inc. 2024 Stock Option and Incentive Plan and MBX Biosciences, Inc. 2024 Employee Stock Purchase Plan,
2)
Registration Statement (Form S-8 No. 333-285846) pertaining to the MBX Biosciences, Inc. 2024 Stock Option and Incentive Plan and MBX Biosciences, Inc. 2024 Employee Stock Purchase Plan, and
3)
Registration Statement (Form S-3 No. 333-291308) of MBX Biosciences, Inc.;
of our report dated March 12, 2026, with respect to the financial statements of MBX Biosciences, Inc. included in this Annual Report (Form 10-K) for the year ended December 31, 2025.
/s/ Ernst & Young LLP
Indianapolis, Indiana
March 12, 2026