ACP-103 cuts PNSS score in Ph II trial

The USA's Acadia Pharmaceuticals reported positive top-line results from a Phase II schizophrenia co-therapy trial with ACP-103, its proprietary and selective 5-HT2A inverse agonist. The trial evaluated ACP-103 together with either Janssen's Risperdal (risperidone), a commonly prescribed atypical antipsychotic, or haloperidol, a generic typical antipsychotic drug.

According to Acadia, the ACP-103 co-therapy arms demonstrated statistically-significant antipsychotic efficacy as measured by the reduction in the Positive and Negative Syndrome Scale, the primary endpoint of the trial. In addition, the co-therapy arm combining ACP-103 with low-dose risperidone demonstrated a statistically-significant improvement in antipsychotic efficacy compared to 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, the firm noted.

"These data clearly demonstrate the advantages of co-therapy with ACP-103 and show the importance of 5-HT receptor antagonism in schizophrenia therapy," said Herbert Meltzer, director of the Psychosis Program at the Vanderbilt University School of Medicine.