A Double-Blind, Placebo-Controlled Study of the Efficacy and Safety of Controlled-Release Fluvoxamine in Patients With Obsessive-Compulsive Disorder

Objective: The aim of this 12-week, double-blind, flexible-dose, placebo-controlled, parallel-arm, multicenter trial was to determine the safety and efficacy of fluvoxamine in a controlled-release (CR) formulation in adult outpatients with obsessive-compulsive disorder (OCD).

Method: 253 adult outpatients with DSM-IV OCD were randomly assigned to receive 100 to 300 mg of fluvoxamine CR (N = 127) or placebo (N = 126) once daily for 12 weeks. Intent-to-treat analyses of efficacy assessments with the Yale-Brown Obsessive Compulsive Scale (YBOCS), Clinical Global Impressions-Severity of Illness scale (CGI-S), and Clinical Global Impressions-Improvement scale (CGI-I) were conducted.

Results: Fluvoxamine CR was significantly (p < .05) superior to placebo in decreasing YBOCS total score beginning at week 2. This early response was sustained at all subsequent visits. At endpoint, there was a mean decrease of 8.5 ± 0.7 (31.7%) in the YBOCS total score compared with baseline in the fluvoxamine CR treatment group versus a mean decrease of 5.6 ± 0.7 (21.2%) in the placebo group (p = .001). Fluvoxamine CR was also significantly superior to placebo in lowering the severity of illness (CGI-S, p = .002) and in producing clinical improvement (CGI-I, p < .01). At endpoint, significantly greater percentages of the fluvoxamine CR treatment group were responders (p = .002) and remitters (p = .019) compared with the placebo group.

Conclusion: Over 12 weeks, fluvoxamine CR treatment was associated with a statistically significant and clinically relevant reduction in OCD severity and was found to be safe and well tolerated. The early onset of therapeutic effect, starting from week 2, was of particular interest.