Extended-release quetiapine fumarate in the treatment of patients with major depressive disorder: adjunct therapy.

Approximately half of the patients with major depressive disorder (MDD) respond insufficiently to current antidepressants, resulting in increased risk of relapse and residual symptoms. Strategies available include dose increase, combination with a second agent, switching antidepressants, adjunct treatment, psychotherapy or exercise. Efficacy and tolerability of once-daily extended-release quetiapine fumarate (quetiapine XR) adjunct to index antidepressant therapy in patients with MDD and an inadequate response to treatment were assessed in two acute studies as part of a global clinical trial program. Quetiapine XR significantly improved depressive symptoms versus placebo. Significant improvement in quality of life versus placebo was confined to elderly patients with MDD. Tolerability was consistent with the known pharmacological profile of quetiapine: the most common adverse events were dry mouth, somnolence, sedation, dizziness and fatigue. Quetiapine XR is approved in the EU, USA and several other countries worldwide as adjunctive treatment for patients with MDD and an inadequate response to previous antidepressants.