Olanzapine versus lithium in the acute treatment of bipolar mania: A double-blind, randomized, controlled trial

BackgroundThis multicenter, double-blind, randomized, controlled study conducted in China examined the efficacy and safety of olanzapine versus lithium in the treatment of patients with bipolar manic/mixed episodes.MethodsPatients with bipolar manic or mixed episode (DSM-IV criteria) and Young Mania Rating Scale (YMRS) score ≥ 20 at screening received olanzapine (5–20 mg/day, n = 69) or lithium carbonate (600–1800 mg/day, n = 71) for 4 weeks. The primary outcome was mean change from baseline in Clinical Global Impressions-Bipolar Version Overall Severity of Illness (CGI-BP) score. Secondary efficacy measures included YMRS, Brief Psychiatric Rating Scale (BPRS), and Montgomery–Åsberg Depression Rating Scale (MADRS) scores. Safety was also assessed.ResultsA significantly greater mean change was observed in olanzapine versus lithium patients in CGI-BP (Overall Severity) (P = 0.009), YMRS (P = 0.013), BPRS (P = 0.032), and CGI-BP (Severity of Mania) (P = 0.012) scores. More olanzapine than lithium patients experienced at least one adverse event possibly related to study drug (P = 0.038). More olanzapine patients had a clinically significant weight increase (≥ 7% of baseline weight) compared to lithium patients (P = 0.009). More olanzapine patients completed the study than lithium patients, although this difference was not statistically significant (olz, 91.3%; lith, 78.9%; P = 0.057).LimitationsNo placebo arm was included; however both treatments have previously been reported to be more effective than placebo.ConclusionsThese results suggest that olanzapine has superior efficacy to lithium in the acute treatment of patients with bipolar mania over a 4-week period. However, adverse events were experienced by a greater number of olanzapine patients than lithium patients.