Background:
Questions have been raised regarding the relative efficacy and tolerability of the different serotonin transport inhibitors in the treatment of obsessive-compulsive disorder. We compared the results from four large multicenter placebo-controlled trials of the serotonin transport inhibitors clomipramine hydrochloride (N=520), fluoxetine hydrochloride (N=355), fluvoxamine maleate (N=320), and sertraline hydrochloride (N=325) for the treatment of obsessive-compulsive disorder.
Methods:
Effect size was calculated by subtracting the end-point drug treatment mean change from the endpoint placebo mean change and dividing by the endpoint pooled change standard deviation. A test for overall differences between effect sizes was conducted, followed by all possible pairwise comparisons. The Yale-Brown Obsessive Compulsive Scale was the primary outcome measure for all four studies.
Results:
All four agents were significantly more effective than placebo, with clomipramine significantly more effective than the other three treatments, which did not differ in effect size. A significantly greater percentage of patients treated with clomipramine were rated much or very much improved than were patients treated with fluoxetine, fluvoxamine, or sertraline.
Conclusion:
While the results of this meta-analysis support the superiority of clomipramine, head-to-head, double-blind comparisons of these compounds would be the best test of comparative efficacy and tolerability.