Fluvoxamine treatment of generalized social anxiety disorder in Japan: a randomized double-blind, placebo-controlled study

The efficacy of selective serotonin reuptake inhibitors (SSRIs) for the treatment of social anxiety disorder (SAD) has been reported in the USA and Europe. However, no clinical investigation has been done with SSRIs in Japanese patients with SAD. This study was performed to determine the effectiveness and safety of fluvoxamine for generalized SAD (GSAD) in Japanese patients. In this double-blind study, patients meeting DSM-IV criteria for GSAD were randomized to receive treatment with fluvoxamine or placebo for 10 wk. Fluvoxamine treatment was initiated at 50 mg/d, and increased by 50 mg weekly to a maximum of 150 or 300 mg/d. The primary efficacy outcome was mean change from baseline on the Liebowitz Social Anxiety Scale -Japanese Version (LSAS-J) total score. The secondary outcomes were response according to the Clinical Global Impressions - Global Improvement (CGI-1) score and three domains of the Sheehan Disability Scale (SDS; used to assess psychosocial impairment). A total of 176 fluvoxamine-treated patients and 89 placebo-treated patients were eligible for the efficacy analysis. At week 10, the fluvoxamine-treated patients had a significantly greater reduction in the LSAS-J total score compared with placebo-treated patients (p = 0.0197), with significantly more fluvoxamine recipients being at least much improved on the CGI-I scale compared with placebo-treated patients (p=0.024). Fluvoxamine-treated patients also had better responses on the SDS compared with placebo-treated patients (p=0.0208). Fluvoxamine was safe and well tolerated. These results suggest that fluvoxamine is effective for the treatment of Japanese patients with GSAD.