The efficacy and safety of lurasidone in bipolar I depression with and without rapid cycling: A pooled post-hoc analysis of two randomized, placebo-controlled trials.

Background: The efficacy and safety of lurasidone monotherapy in patients with bipolar I depression with or without rapid cycling has not been previously investigated.

Methods: We performed subgroup analysis (rapid cycling/non-rapid cycling) of pooled data from two 6-week, randomized, double-blind, placebo-controlled trials of lurasidone monotherapy (20-60 mg/day or 80-120 mg/day). Analyses included mean change from baseline to week 6 in Montgomery-Åsberg Depression Rating Scale (MADRS) total score. Safety assessments included the number of treatment-emergent adverse events (TEAEs) and laboratory assessments.

Results: Of 1024 patients randomized, 85 were rapid cycling. Mean change in MADRS total score in patients with non-rapid cycling and rapid cycling, respectively, was -14.8 (effect size = 0.47) and - 12.8 (effect size = 0.04) in the lurasidone 20-60 mg/day group, -14.3 (effect size = 0.41) and - 13.0 (effect size = 0.02) in the lurasidone 80-120 mg/day group and -10.6 and -13.3 in the placebo group. The most common TEAE in each subgroup was akathisia in both lurasidone groups. Treatment-emergent mania was reported only in a small number of rapid cycling and non-rapid cycling patients.

Limitations: This was a post-hoc analysis of a short-term study that excluded patients with ≥8 cycles in the past year.

Conclusions: In patients with non-rapid cycling bipolar depression, lurasidone monotherapy significantly improved depressive symptoms relative to placebo at both the 20-60 mg/day and 80-120 mg/day doses. In patients with rapid cycling, both doses of lurasidone displayed depressive symptom score reduction from baseline, but significant improvement was not observed likely due to high levels of improvement on placebo and small sample size.