Pimavanserin – Schizophrenia Negative Symptoms


Pimavanserin is a proprietary small molecule that we have advanced to Phase 2 development for negative symptoms of schizophrenia. Pimavanserin is a selective serotonin inverse agonist (SSIA) preferentially targeting 5-HT2A receptors. Its distinct mechanism of action targets serotonergic 5-HT2A receptors while avoiding activity at dopamine and other receptors commonly targeted by other antipsychotics.

About Schizophrenia

According to the National Institute of Mental Health, approximately one percent of the U.S. population develops schizophrenia during their lifetime. Schizophrenia is a chronic, debilitating mental illness characterized by thought disorder, emotional and cognitive dysfunction, and behavioral disturbances. These disturbances may include positive symptoms, including hallucinations, delusions, and disorganized speech, as well as a range of negative symptoms, including flat affect, loss of interest, emotional withdrawal, and cognitive impairment.

Studies show that about 40 to 50 percent of schizophrenia patients suffer from prominent negative symptoms. While currently available antipsychotic treatments for schizophrenia target positive symptoms, most patients remain functionally impaired because of negative symptoms, cognitive deficits, and limited social function.


In April 2019, we completed enrollment of the Phase 2 ADVANCE study evaluating the efficacy and safety of adjunctive use of pimavanserin in patients with schizophrenia who have predominant negative symptoms. The ADVANCE study is a 26-week, randomized, double-blind, placebo-controlled, multi-center study with approximately 380 patients with inadequate response to current antipsychotic treatment for schizophrenia. The primary endpoint of the study is change from baseline on the Negative Symptom Assessment-16 (NSA-16) total score. We expect to report results around the end of 2019.