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FEDERAL REGISTER · NOTICEAugust 29, 2025NOTICE — NO LEGAL EFFECT

Amylyx Pharmaceuticals, Inc.; Withdrawal of Approval of New Drug Application for RELYVRIO (Sodium Phenylbutyrate and Taurursodiol) for Suspension, 3 Gram/Packet and 1 Gram/Packet

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Document details are published in the U.S. Federal Register; SPEQ surfaces them for reference and is not affiliated with or endorsed by the FDA or the Office of the Federal Register. The authoritative text is on federalregister.gov.

Document type
Notice
Agency
Health and Human Services Department
Published
August 29, 2025
Document number
2025-16646
ABSTRACT

The Food and Drug Administration (FDA or Agency) is withdrawing approval of the new drug application (NDA) for RELYVRIO (sodium phenylbutyrate and taurursodiol) for suspension, 3 gram (g)/ packet and 1 g/packet, held by Amylyx Pharmaceuticals, Inc. (Amylyx), 43 Thorndike St., Cambridge, MA 02141. Amylyx has voluntarily requested that FDA withdraw approval of this application and has waived its opportunity for a hearing.

Abstract as published in the Federal Register.

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