Key Highlights

  • Acadia Pharmaceuticals shares closed at $22.18 today, down 12.78%.
  • The company's drug remlifanserin narrowly missed the primary endpoint in the Phase 2 portion of the RADIANT trial for Alzheimer's disease psychosis, with a standardized effect size of 0.26 and a p-value of 0.0603.
  • The drug achieved nominal statistical significance on a key secondary endpoint, with a standardized effect size of 0.37 and a p-value of 0.0077.
  • A research firm trimmed its price target to $33 from $40 while maintaining a bullish rating, and the company plans to continue Phase 3 development of the 60 mg dose while dropping the 30 mg arm.

Primary Endpoint Narrowly Missed

Acadia Pharmaceuticals (NASDAQ:ACAD) shares closed sharply lower today after the company reported topline results from the Phase 2 portion of its RADIANT trial evaluating remlifanserin for Alzheimer's disease psychosis. The 60 mg once-daily dose narrowly missed the primary endpoint of change in hallucination and delusion symptoms, posting a standardized effect size of 0.26 with a p-value of 0.0603, just short of conventional statistical significance, while achieving nominal significance on the key secondary endpoint measuring overall symptom severity, with a stronger effect size of 0.37.

Management Still Plans to Advance Into Phase 3

Despite the narrow miss, management said it still plans to advance Phase 3 development of the 60 mg dose while dropping the ineffective 30 mg arm from the program, citing meaningful and consistent efficacy trends across endpoints and a favorable safety profile with no signal of QT prolongation or negative impact on motor symptoms or cognition. A research firm trimmed its price target to $33 from $40 while maintaining a bullish rating, and a separate firm reiterated its own bullish stance with a $41 target, calling the data directionally supportive even amid uncertainty about the drug's ultimate regulatory and commercial prospects.

A Large Unmet Need Amid Broader Sector Softness

Acadia Pharmaceuticals is a San Diego-based commercial-stage biopharmaceutical company focused on central nervous system disorders and rare diseases, with an existing portfolio including the first and only FDA-approved treatments for Parkinson's disease psychosis and Rett syndrome. The selloff follows a strong run earlier this year tied to a positive European regulatory opinion on its Rett syndrome drug, and comes amid broader healthcare sector softness and rising bond yields pressuring valuations across the group. There is currently no FDA-approved therapy for Alzheimer's disease psychosis.