Acadia’s schizophrenia drug trial did not meet primary endpoint

US-based biopharmaceutical company Acadia Pharmaceuticals has announced that its Phase III ADVANCE-2 clinical trial evaluating pimavanserin for the treatment of negative symptoms in schizophrenia did not meet its primary endpoint.

The 26-week trial, which enrolled 454 adult participants experiencing negative symptoms despite control of positive symptoms with ongoing antipsychotic therapy, administered a 34mg dose of pimavanserin.

Efficacy was assessed using the Negative Symptom Assessment-16 (NSA-16) scale, evaluating various negative symptoms across five subscales, including blunted affect, poor socialization, and lack of motivation.

Despite this, pimavanserin did not demonstrate a statistically significant difference compared to placebo in the change from baseline to week 26 on the NSA-16 total score, the study's primary endpoint.

However, the safety and tolerability profile of pimavanserin remained consistent with previous trials, although the placebo effect observed in ADVANCE-2 was higher than that reported in the ADVANCE-1 trial.

Overall, the drug was well-tolerated, with an adverse event rate of 30.4% compared to 40.3% in the placebo group.