Lurasidone Monotherapy in the Treatment of Bipolar I Depression: a Randomized, Double-blind, Placebo-controlled Study

Objective: The authors evaluated the efficacy and safety of lurasidone in the treatment of patients with major depressive episodes associated with bipolar I disorder.

Method: Patients were randomly assigned to receive double-blind treatment with lurasidone (20-60 mg/day [N=166] or 80-120 mg/day [N=169]) or placebo (N=170) for 6 weeks. Primary and key secondary endpoints were change from baseline to week 6 on the Montgomery-Åsberg Depression Rating Scale (MADRS) and depression severity score on the Clinical Global Impressions scale for use in bipolar illness (CGI-BP), respectively.

Results: Lurasidone treatment significantly reduced mean MADRS total scores at week 6 for both the 20-60 mg/day group (-15.4; effect size=0.51) and the 80-120 mg/day group (-15.4; effect size=0.51) compared with placebo (-10.7). Similarly, lurasidone treatment resulted in significantly greater endpoint reduction in CGI-BP depression severity scores for both the 20-60 mg/day group (-1.8; effect size=0.61) and the 80-120 mg/day group (-1.7; effect size=0.50) compared with placebo (-1.1). Both lurasidone groups also experienced significant improvements compared with placebo in anxiety symptoms and in patient-reported measures of quality of life and functional impairment. Discontinuation rates due to adverse events were similar in the 20-60 mg/day (6.6%), 80-120 mg/day (5.9%), and placebo (6.5%) groups. The most frequent adverse events associated with lurasidone were nausea, headache, akathisia, and somnolence. Minimal changes in weight, lipids, and measures of glycemic control were observed with lurasidone.

Conclusion: Monotherapy with lurasidone in the dosage range of 20-120 mg/day significantly reduced depressive symptoms in patients with bipolar I depression. Lurasidone was well tolerated, with few changes in weight or metabolic parameters.