SAN FRANCISCO—Adding samidorphan to olanzapine did not diminish the antipsychotic efficacy of olanzapine alone in adults with schizophrenia, according to data presented during a poster session at the American Psychiatric Association’s annual meeting.
“ALKS 3831, currently under development for the treatment of schizophrenia, is composed of a flexible dose of olanzapine and a fixed dose of 10 mg of samidorphan,” wrote poster presenter Adam Simmons and coauthors Peter Weiden, MD, David McDonnell, Ying Jiang, Lauren DiPetrillo, and Bernard Silverman. “In phase 1 and phase 2 clinical studies, samidorphan mitigated olanzapine-associated weight gain.”
The poster summarized antipsychotic efficacy results for ALKS 3831, compared with olanzapine alone, from a trio of double-blinded, randomized trials.
In the first study—a 12-week phase 2 trial of adults without a recent exacerbation of schizophrenia—those randomized to ALKS 3831 showed a similar change as patients randomized to olanzapine alone in Positive and Negative Symptoms Scale (PANSS) scores between baseline and week 12.
In the second study, a 9- to 15-month phase 2 trial of adults with schizophrenia and alcohol use disorder with a recent schizophrenia exacerbation, overall gains in PANSS scores were similar for ALKS 3831 and olanzapine alone.
The third study was a 4-week phase 3 trial of adults experiencing an acute exacerbation of schizophrenia. At week 4, change from baseline on PANSS scores were, again, similar between the 2 treatments.
“In three separate studies with clinically unique patient populations with schizophrenia, treatment with ALKS 3831 resulted in similar antipsychotic efficacy to olanzapine, as evaluated by change in PANSS total score,” researchers wrote.
“Antipsychotic efficacy of ALKS 3831 across three olanzapine-controlled clinical studies.” Abstract presented at: the American Psychiatric Association Annual Meeting; May 20, 2019; San Francisco, CA.