Evaluation of eszopiclone discontinuation after cotherapy with fluoxetine for insomnia with coexisting depression

Background: Insomnia and major depressive disorder (MDD) may coexist. This study evaluated hypnotic discontinuation effects following an 8-week placebo-controlled study of eszopiclone/fluoxetine cotherapy in patients with insomnia and comorbid MDD. Methods: Patients meeting DSM-IV criteria for MDD and insomnia received fluoxetine each morning for 8 weeks and were randomized to concomitant treatment with nightly eszopiclone 3mg (cotherapy) or placebo (monotherapy). Thereafter, patients received 2 weeks of continued fluoxetine plus single-blind placebo. Results: Incidence rates of central nervous system (CNS) and potentially CNS-related adverse events (AEs) during the run-out period were similar between treatment groups (8.8% with monotherapy vs 9.8% with cotherapy), and there was no evidence of benzodiazepine withdrawal AEs. Physician-assessed Clinical Global Impression improvements in depressive symptoms were maintained after eszopiclone discontinuation. Improvements in 17-item Hamilton-Depression Rating Scale (HAM-D-17) scores with cotherapy versus monotherapy seen at Week 8 (p= .0004) were maintained at Week 10 (p< .0001) and significantly higher depression response and remission rates were observed after cotherapy at Week 10 (p< .02). Patients discontinued from eszopiclone maintained improvements in SL (sleep latency), WASO (wake after sleep onset), and TST (total sleep time) during the 2 weeks following discontinuation (P< 05). Conclusions: In this study, eszopiclone discontinuation did not result in significant CNS or benzodiazepine withdrawal AEs, rebound insomnia, or rebound depression; and improvements in sleep and depressive symptoms were maintained.