Levetiracetam in social phobia: a placebo controlled pilot study

While serotonergic antidepressants are now established as first-line pharamcotherapy for generalized social anxiety disorder (SAD), other agents with different mechanisms have shown promise in treating SAD. The aim of this pilot study is to examine the efficacy and safety of levetiracetam (LEV), an anticonvulsant with calcium channel modulating properties, in treating SAD. Adult outpatients meeting DSM-IV criteria for SAD were randomly assigned (2:1) to double-blind treatment with either LEV (500-3000 mg/day) or placebo (PBO) for 7 weeks. The primary outcome measures were the change from baseline in the Brief Social Phobia Scale (BSPS) and response using the Clinical Global Impression of Improvement scale (CGI-I). The mean (SD) BSPS scores at baseline and endpoint were 45.4 (9.7) and 31.2 (19.7) for LEV (n=9), compared to 43.5 (8.4) and 37.8 (19.9) for PBO (n =7) (ITT; ns). Rates of response were 22% for LEV and 14% for PBO using the CGI-I. Using a BSPS response criterion (>30% reduction), response rates were 44% for LEV and 14% for PBO. The effect sizes of LEV relative to PBO were 0.33 for the BSPS and 0.50 for the LSAS. In summary, the results of this study, while negative on the pre-defined measures, suggest promise for LEV as a new treatment of SAD. Further work should be carried out with larger sample sizes and optimal dosing strategies of the drug.