Placebo-controlled trial of moclobemide in social phobia

Moclobemide, a reversible inhibitor of monoamine oxidase A, previously has been reported to have efficacy in the treatment of social phobia. Seventy-seven non-responders to one week of single-blind placebo were randomly assigned to moclobemide or placebo for eight weeks of double-blind treatment. Outcome was assessed by independent evaluator, treating psychiatrist and self-ratings. After eight weeks, patients who were at least minimally improved continued treatment for a further eight weeks. Intention-to-treat sample response rates at week 8 were 7/40 (17.5%) for the moclobemide group and 5/37 (13.5%) for placebo (NS). Moclobemide was significantly superior to placebo on 2 of 10 primary outcome measures. Moclobemide was well tolerated. Moclobemide may have efficacy in the treatment of social phobia, but absence of significant differences on most primary outcome measures and small effect sizes for all outcome measures suggest that the magnitude of its clinical effect is small.