Sunovion, PsychoGenics nondopamine schizophrenia drug meets phase 2 endpoint

Sunovion Pharmaceuticals and PsychoGenics unveiled positive phase 2 results for a new schizophrenia treatment that does not bind to the brain’s dopamine receptors.

While its exact mechanism of action is unknown, the two companies believe that SEP-363856 activates trace amine-associated receptor 1 (TAAR1) in addition to the serotonin receptor 5-HT1A without binding to other serotonergic receptors.

TAAR1 helps regulate dopamine, norepinephrine and serotonin transmission, and has effects in the brain’s immune system. Direct activation of dopamine and serotonin receptors, meanwhile, is believed to mediate the effects of current antipsychotic drugs, which for decades have focused on blocking dopamine receptors, the companies said.

The placebo-controlled study met its primary endpoint, enrolling 245 hospitalized patients with acute worsening of schizophrenia and demonstrating improvements in a total syndrome scale over four weeks of daily treatment. Improvements were also seen in the overall severity of illness and psychopathology subscales.

“The results of this first placebo-controlled study assessing the utility of SEP-363856 in patients with schizophrenia are exciting, and we intend to advance the development of this novel investigational medicine as quickly as possible,” said Sunovion Chief Medical Officer Antony Loebel, who also heads global clinical development for Sumitomo Dainippon Pharma Group. The study’s results were presented at annual meeting of the American College of Neuropsychopharmacology.

SEP-363856 was identified through a collaboration employing PsychoGenics’ SmartCube neurological drug discovery platform, through a mechanism-independent approach.

The in vivo SmartCube platform pits treated mice against a sequence of challenges, while capturing bioinformatics and behavioral profiles to analyze the potential of different compounds to treat psychiatric disorders.

The drug, which is also being studied in Parkinson’s disease psychosis, is jointly owned by Sunovion and PsychoGenics, with Sunovion holding exclusive rights to global development and commercialization.