Continuation treatment of OCD: double-blind and open-label experience with fluoxetine

Recent advances in the pharmacotherapy of obsessive compulsive disorder (OCD) have led to a significant reduction in suffering and a return to productive living for many patients previously considered refractory to treatment. However, OCD can be a chronic disorder that significantly detracts from an individual's well-being. Potent inhibitors of 5-hydroxytryptamine (5-HT) reuptake have emerged as the first-line choice in the pharmacotherapy of OCD. These members of the therapeutic armamentarium for OCD, while associated with acute symptomatic improvement, have not been extensively studied during continuation therapy. In this study, 274 primary OCD subjects completed a 13-week, double-blind, placebo-controlled trial of three fixed doses of fluoxetine. Treatment responders (n = 76) continued their blinded treatment, whereas acute fixed-dose nonresponders began an open-label trial on their maximally tolerated dose (up to 80 mg daily) for 24 weeks. Responders maintained their acute treatment gains; in addition, all three doses of fluoxetine (20, 40, and 60 mg) were associated with further Y-BOCS improvement over the 24-week extension. Fluoxetine 60 mg achieved a statistically significantly greater reduction in Y-BOCS than placebo during the continuation. Open-label study subjects (n = 198) benefited from dose titration, with two thirds achieving a clinical response during the subsequent 24 weeks. Fluoxetine was well tolerated during both 24-week continuation periods. Only 4 (5.7%) of 70 subjects treated with fluoxetine in the responder extension terminated early due to an adverse event. The open-label extension, fluoxetine (to 80 mg), also demonstrated a low rate of adverse events; the profile of events was consistent with the extensive fluoxetine experience in other clinical populations. In conclusion, fluoxetine continuation treatment in OCD was associated with a maintained/improved symptomatic profile in most cases. Further dose titration improved the outcome of many acute, fixed-dose nonresponders. Continuation treatment with fluoxetine appeared to be well tolerated with few late-emergent adverse events.