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# Acadia Pharmaceuticals Nixes Schizophrenia Drug
- URL: https://www.fdaweb.com/acadia-pharmaceuticals-nixes-schizophrenia-drug/
- Published: 2024-03-12T12:00:00.000Z
- Updated: 2026-09-14T14:25:04.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5156534

Acadia Pharmaceuticals says it is scrapping pimavanserin for treating negative symptoms of schizophrenia after announcing “disappointing” top-line results from the Phase 3 ADVANCE-2 trial. “Pimavanserin did not demonstrate a statistically significant improvement over placebo on the study’s primary endpoint, the change from baseline to week 26 on the Negative Symptom Assessment-16 (NSA-16) total score (-11.8 vs. -11.1; p=0.4825; effect size=0.07),” it says. On the safety side, the trial found pimavanserin’s safety and tolerability profile consistent with previous clinical trials and showing a low rate of adverse events.

“We are disappointed the trial did not meet its primary endpoint given the significant unmet need in patients with negative symptoms of schizophrenia,” Acadia says. “We will continue to analyze these data with our scientific advisors, but we do not intend to conduct any further clinical trials with pimavanserin.”

ADVANCE-2 used the NSA-16 scale, which measures change on the wide range of predominant negative symptoms that patients experience, looking at 16 different items in five subscales and covers symptoms such as blunted affect, poor socialization and lack of motivation, according to the company. “The change from baseline observed in the pimavanserin arm of ADVANCE-2 was similar to the change from baseline observed at the 34 milligram dose in ADVANCE-1 (-11.8 vs. -11.6); however, the placebo effect in ADVANCE-2 was higher than the placebo effect observed in ADVANCE-1 (-11.1 vs. -8.5),” it notes.