Olanzapine/Samidorphan Offers Observable Benefit for Treatment of Negative Schizophrenia Symptoms
The combination of olanzapine and samidorphan (OLZ/SAM) may have a significant long-term treatment benefit on the negative symptoms of schizophrenia, according to research presented at the 2025 NEI Spring Congress.
“Addressing negative symptoms of schizophrenia can be a treatment challenge,” wrote Roger S. McIntyre, MD, FRCPC, Department of Psychiatry and Pharmacology, University of Toronto, Toronto, ON, Canada, and study coauthors. “This post hoc analysis examined the long-term effect of the combination of olanzapine and samidorphan (OLZ/SAM) on negative symptoms.”
The researchers evaluated data from a 4-week olanzapine and placebo-controlled OLZ/SAM study for the treatment of acute schizophrenia (n=281). Each participant also had ≥1 postbaseline visit in a 52-week open-label extension study.
In their analysis, the researchers measured treatment effect through the change in baseline mean Positive and Negative Syndrome Scale (PANSS) Marder Negative Symptoms Factor score at week 56. They also measured the mean change in Marder Negative Symptoms Factor score in a high baseline negative symptoms subgroup (Marder Negative Symptoms Factor score ≥24), and in a high negative/low positive symptoms subgroup (Marder Negative Symptoms Factor score ≥24, PANSS positive symptoms factor score ≤19, and score of ≥4 on 2 of 3 PANSS blunted affect, passive/apathetic social withdrawal, or lack of spontaneity/flow of conversation items).
At week 56, the mean change in Marder Negative Symptoms Factor score was –8.5 (0.41; n=183) from baseline. In the high baseline negative symptom subgroup, the mean change was –9.8 (0.50; n=124). The high negative symptoms/low positive symptoms subgroup also saw a decrease, with a mean change of –8.9 (0.90; n=37).
“Results of this post hoc analysis suggest that OLZ/SAM provides a treatment benefit for negative symptoms of schizophrenia that is observable over long-term therapy,” the authors concluded.
Writing and editorial support were provided by Peloton Advantage, LLC, and funded by Alkermes, Inc.
Reference
McIntyre RS, Matthews DM, Harris ME, et al. Treatment effects of olanzapine/samidorphan on negative symptoms in patients with schizophrenia: a post hoc analysis. NEI Spring Congress; May 8-10; Philadelphia, Pennsylvania.
