Lundbeck and Otsuka report new data from their trials evaluating brexpiprazole for the treatment of manic episodes associated with bipolar I disorder.
Data from two global Phase III clinical trials evaluating the safety and efficacy of brexpiprazole for the treatment of patients with manic episodes associated with bipolar I disorder did not meet the primary endpoint. The duration of the randomized phase of each trial was 3 weeks.
The two multicenter, randomized, double-blind studies of brexpiprazole versus placebo comprised a total of approximately 650 bipolar I patients who experienced an acute manic episode, with or without mixed features, that required hospitalization. The primary efficacy measure to assess the psychiatric signs and symptoms was determined using the Young Mania Rating Scale (YMRS). The YMRS score is a widely-used clinician rating scale to assess mania symptoms based on a patient’s subjective reports of their condition and clinical observations made during interviews.i
The studies did not meet the primary endpoint of statistical separation from placebo as measured by the Young Mania Rating Scale (YMRS) at week 3. In both studies, the placebo effect on the rating scales was substantially higher than anticipated.
Brexpiprazole was generally well tolerated in the trials. The most common adverse reactions observed during the trials were akathisia (6.5%) and headache (5%) and no other adverse events was greater than 3% for patients receiving brexpiprazole across the 2 studies.
The next steps
The companies will conduct a thorough analysis of the study results to determine what the next steps will be. The results from the bipolar 1 disorder mania studies do not have any bearing on the approved indications of brexpiprazole as treatment for people living with major depressive disorder (MDD) and schizophrenia.