Serina Therapeutics Submits Complete Response To FDA Clinical Hold Letter For SER-252, Lead Program For Advanced Parkinson's Disease

– Company addresses FDA requests regarding formulation excipient 

– Global site start-up activities continue, with first-patient-in for registrational Phase 1b study targeted for Q1 2026, subject to FDA feedback

HUNTSVILLE, Dec. 10, 2025 (GLOBE NEWSWIRE) -- Serina Therapeutics, Inc. ("Serina" or the "Company") (NYSE:SER), a clinical-stage biotechnology company advancing its lead Investigational New Drug ("IND") candidate, SER-252, for advanced Parkinson's disease, enabled by its proprietary POZ PlatformTM drug optimization technology, today announced that it has submitted a complete response to the U.S. Food and Drug Administration's ("FDA") clinical hold letter for SER-252, the Company's lead program for advanced Parkinson's disease.

As previously disclosed, the FDA placed the Company's Investigational New Drug ("IND") application for SER-252 on clinical hold pending additional information related to a commonly used formulation excipient. On November 25, 2025, the FDA issued a formal full clinical hold letter specifying the information required to permit initiation of the planned Phase 1b registrational study, SER-252-1b.

The issues identified by the FDA do not relate to the apomorphine active drug substance, its mechanism of action, the use of the enFuse device (Enable Injections) or the broader 505(b)(2) NDA development pathway previously discussed with the Agency.

Serina's complete response, submitted on December 9, 2025, includes:

• A detailed data package supporting the proposed use of trehalose as a subcutaneous excipient at the intended dose, including comparative information to approved products containing trehalose and additional nonclinical analyses; and
• A revised protocol to initiate the single ascending dose (SAD) phase. Initiation of the SAD phase of the SER-252-1b trial is anticipated to begin in Q1 2026.