A Double-Blind, Placebo-Controlled Study of the Efficacy and Safety of Desvenlafaxine Succinate in the Treatment of Major Depressive Disorder

Objective: This study evaluated the efficacy and safety of desvenlafaxine succinate extended-release in major depressive disorder (MDD).

Method: Adult outpatients with DSM-IV-defined MDD were randomly assigned to desvenlafaxine 100 mg/day (N = 114), 200 mg/day (N = 116), or 400 mg/day (N = 113) or placebo (N = 118) for 8 weeks. Efficacy variables included change from baseline in the 17-item Hamilton Rating Scale for Depression (HAM-D₁₇, the primary efficacy measure), Clinical Global Impressions-Improvement scale (CGI-I), Montgomery-Asberg Depression Rating Scale, Clinical Global Impressions-Severity of Illness scale (CGI-S), rates of response (>= 50% decrease from baseline HAM-D₁₇ score) and remission (HAM-D₁₇ score <= 7), and Visual Analog Scale-Pain Intensity overall score. The study was conducted from November 2003 to November 2004.

Results: At the final on-therapy evaluation, the mean HAM-D₁₇ scores for desvenlafaxine 100 mg/day (12.75) and 400 mg/day (12.50) were significantly lower than for placebo (15.31; p = .0038 and p = .0023, respectively); for desvenlafaxine 200 mg/day, the mean score was 13.31 (p = .0764). CGI-I and Montgomery-Asberg Depression Rating Scale results were significant for all groups; CGI-S results were significant with 100 mg/day and 400 mg/day. Response rates were significantly greater for desvenlafaxine 100 mg/day (51%) and 400 mg/day (48%) versus placebo (35%; p = .017 and p = .046, respectively); the response rate for desvenlafaxine 200 mg/day was 45% (p = .142). Remission rates were significantly greater for desvenlafaxine 400 mg/day (32%) versus placebo (19%; p = .035); remission rates were 30% for desvenlafaxine 100 mg/day (p = .093) and 28% for desvenlafaxine 200 mg/day (p = .126). Visual Analog Scale-Pain Intensity results were significant for desvenlafaxine 100 mg/day versus placebo (p = .002), but not for the higher doses. The most commonly reported adverse events were nausea, insomnia, somnolence, dry mouth, dizziness, sweating, nervousness, anorexia, constipation, asthenia, and abnormal ejaculation/orgasm.

Conclusions: Desvenlafaxine is effective and well tolerated in the short-term treatment of MDD.