ACADIA ANNOUNCES DATA FROM SCHIZOPHRENIA CO-THERAPY STUDY

Acadia Pharmaceuticals has announced positive top-line results from its Phase II schizophrenia co-therapy trial with ACP-103, its proprietary and selective 5-HT2A inverse agonist.

The multicenter, randomized, double-blind, placebo-controlled, six-week trial evaluated ACP-103 co-therapy when used together with either risperidone, a commonly prescribed atypical antipsychotic drug, or haloperidol, a generic typical antipsychotic drug. The trial enrolled 423 patients across sites in the U.S. and Brazil. Patients were randomly assigned to one of five study arms: ACP-103 plus low-dose risperidone, low-dose risperidone plus placebo, high-dose risperidone plus placebo, ACP-103 plus haloperidol or haloperidol plus placebo. The primary endpoint of the study was antipsychotic efficacy as measured after day 42 compared with baseline in each of the two ACP-103 co-therapy arms using the Positive and Negative Syndrome Scale (PANSS).

The co-therapy arms with ACP-103 demonstrated statistically significant antipsychotic efficacy as measured by the reduction in the PANSS. In addition, the co-therapy arm combining ACP-103 with low-dose risperidone demonstrated a statistically significant improvement in antipsychotic efficacy compared with low-dose risperidone plus placebo, and comparable efficacy to high-dose risperidone plus placebo. Co-therapy with ACP-103 also led to a faster onset of antipsychotic action and an improved side effect profile.

Each of the treatments was generally safe and well tolerated. Adverse events were comparable among the five study arms and were generally characterized as mild to moderate. The most common adverse events were sedation, headache and agitation. There were three serious adverse events in the study that were deemed to be drug-related, each of which occurred in a risperidone-plus-placebo arm.