Efficacy and tolerability of extended release quetiapine fumarate (quetiapine XR) monotherapy in major depressive disorder: A placebo-controlled, randomized study☆

Background Evaluate the efficacy and tolerability of extended release quetiapine fumarate (quetiapine XR) once-daily monotherapy for patients with major depressive disorder (MDD). Methods In this 10-week, (8-week active treatment phase and 2-week drug-discontinuation/tapering phase), multicenter, parallel-group, placebo-controlled, double-blind, randomized, Phase III study (D1448C00003: Opal), patients initially received quetiapine XR 150 mg/day or placebo. At Week 2, inadequate responders (< 20% reduction in MADRS total score) were up-titrated to 300 mg/day quetiapine XR or matching placebo for the final 6 weeks. Primary endpoint: change from randomization to Week 8 in MADRS total score. Secondary endpoints included: MADRS response (≥ 50% reduction in total score from randomization) and changes from randomization to Week 8 in HAM-D and CGI-S. Results 310 patients were randomized. At Week 8, quetiapine XR significantly reduced mean MADRS total score versus placebo (−16.49 vs −13.10, respectively; p   10% any group during the randomized phase) for quetiapine XR and placebo, respectively were dry mouth (32.9% and 6.5%), sedation (21.7% and 1.9%), somnolence (20.4% and 5.2%), and headache (10.5% and 10.3%). Limitations The study was not designed to compare quetiapine XR 150 mg/day and 300 mg/day; it was intended to reflect dose titration that might occur in clinical practice. Conclusions Quetiapine XR monotherapy is effective in patients with MDD, with symptom improvement seen as early as Week 1, and tolerability results consistent with the known profile of quetiapine.