Double-blind, placebo-controlled study of lurasidone monotherapy for the treatment of bipolar I depression.

Aim: Previous studies conducted primarily in the USA and Europe have demonstrated the efficacy and safety of lurasidone 20-120 mg/day for the treatment of bipolar I depression. The aim of the current study was to evaluate the efficacy and safety of lurasidone monotherapy for the treatment of bipolar I depression among patients from diverse ethnic backgrounds, including those from Japan.

Methods: Patients were randomly assigned to double-blind treatment for 6 weeks with lurasidone, 20-60 mg/day (n = 184) or 80-120 mg/day (n = 169), or placebo (n = 172). The primary end-point was change from baseline to Week 6 on the Montgomery-Åsberg Depression Rating Scale (MADRS).

Results: Lurasidone treatment significantly reduced mean MADRS total scores from baseline to Week 6 for the 20-60-mg/day group (-13.6; adjusted P = 0.007; effect size = 0.33), but not for the 80-120-mg/day group (-12.6; adjusted P = 0.057; effect size = 0.22) compared with placebo (-10.6). Treatment with lurasidone 20-60 mg/day also improved MADRS response rates, functional impairment, and anxiety symptoms. The most common adverse events associated with lurasidone were akathisia and nausea. Lurasidone treatments were associated with minimal changes in weight, lipids, and measures of glycemic control.

Conclusion: Monotherapy with once daily doses of lurasidone 20-60 mg, but not 80-120 mg, significantly reduced depressive symptoms and improved functioning in patients with bipolar I depression. Results overall were consistent with previous studies, suggesting that lurasidone 20-60 mg/day is effective and safe in diverse ethnic populations, including Japanese.