EFFICACY AND TOLERABILITY OF SEROTONIN TRANSPORT INHIBITORS IN OBSESSIVE-COMPULSIVE DISORDER - A METAANALYSIS

Background: Questions have been raised regarding the relative efficacy and tolerability of the different serotonin transport inhibitors in t he treatment of obsessive-compulsive disorder. We compared the results from four large multicenter placebo-controlled trials of the serotoni n transport inhibitors clomipramine hydrochloride (N=520), fluoxetine hydrochloride (N=355), fluvoxamine maleate (N=320), and sertraline hyd rochloride (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 divid ing by the endpoint pooled change standard deviation. A test for overa ll differences between effect sizes was conducted, followed by all pos sible pairwise comparisons. The Yale-Brown Obsessive Compulsive Scale was the primary outcome measure for all four studies. Results: All fou r agents were significantly more effective than placebo, with clomipra mine significantly more effective than the other three treatments, whi ch did not differ in effect size. A significantly greater percentage o f patients treated with clomipramine were rated much or very much impr oved than were patients treated with fluoxetine, fluvoxamine, or sertr aline. Conclusion: While the results of this meta-analysis support the superiority of clomipramine, head-to-head, double-blind comparisons o f these compounds would be the best test of comparative efficacy and t olerability.