A multicenter, randomized, double-blind, controlled phase 3 trial of fixed-dose brexpiprazole for the treatment of adults with acute schizophrenia.

The objective of this study was to evaluate the efficacy, safety and tolerability of brexpiprazole versus placebo in adults with acute schizophrenia. This was a 6-week, multicenter, placebo-controlled double-blind phase 3 study. Patients with acute schizophrenia were randomized to brexpiprazole 1, 2 or 4 mg, or placebo (2:3:3:3) once daily. The primary endpoint was changed from baseline at week 6 in Positive and Negative Syndrome Scale (PANSS) total score; the key secondary endpoint was Clinical Global Impressions-Severity (CGI-S) at week 6. Brexpiprazole 4 mg showed statistically significant improvement versus placebo (treatment difference: -6.47, p=0.0022) for the primary endpoint. Improvement compared with placebo was also seen for the key secondary endpoint (treatment difference: -0.38, p=0.0015), and on multiple secondary efficacy outcomes. Brexpiprazole 1 and 2mg also showed numerical improvements versus placebo, although p>0.05. The most common treatment-emergent adverse events were headache, insomnia and agitation; incidences of akathisia were lower in the brexpiprazole treatment groups (4.2%-6.5%) versus placebo (7.1%). Brexpiprazole treatment was associated with moderate weight gain at week 6 (1.23-1.89 kg versus 0.35 kg for placebo); there were no clinically relevant changes in laboratory parameters and vital signs. In conclusion, brexpiprazole 4 mg is an efficacious and well-tolerated treatment for acute schizophrenia in adults. Clinical Trials.gov NCT01393613; BEACON trial.