Acadia's Phase 3 Pimavanserin Trial for Schizophrenia Negative Symptoms: Top-Line Results

Acadia Pharmaceuticals Inc. recently reported the outcomes of the Phase 3 ADVANCE-2 trial, which was designed to assess the efficacy of pimavanserin in addressing the negative symptoms of schizophrenia. The study, unfortunately, did not meet its primary goal, as pimavanserin failed to show a significant difference compared to a placebo in improving the symptoms, as measured by the Negative Symptom Assessment-16 (NSA-16) total score. Despite this setback, the drug maintained a favorable safety profile with a low incidence of adverse events.

The company's CEO, Steve Davis, expressed disappointment over the results, acknowledging the significant need for treatments targeting the negative symptoms of schizophrenia. He stated that Acadia will not proceed with further clinical trials for pimavanserin in this context. The CEO also extended his gratitude to the participants and researchers involved in the study.

The ADVANCE-2 trial was a double-blind, randomized, placebo-controlled study that spanned 26 weeks and involved 454 adult patients. These patients were suffering from predominant negative symptoms of schizophrenia and had their positive symptoms under control with ongoing antipsychotic treatments. The NSA-16 scale was utilized to measure changes in a range of negative symptoms, encompassing 16 different items across five subscales.

It is noteworthy that the observed changes in the pimavanserin group were similar to those seen in the ADVANCE-1 trial at the same dosage. However, the placebo effect in the ADVANCE-2 trial was more pronounced than in the previous study. In terms of tolerability, pimavanserin showed an adverse event rate of 30.4%, which was lower than the 40.3% rate observed in the placebo group.

Acadia Pharmaceuticals has been a pioneer in neuroscience for three decades, focusing on developing solutions for critical healthcare needs. The company has successfully developed and commercialized the first FDA-approved drug for Parkinson’s disease psychosis and Rett syndrome. Acadia continues to explore treatments for Prader-Willi syndrome, Alzheimer’s disease psychosis, and other neuropsychiatric symptoms associated with central nervous system disorders.