Desvenlafaxine 50 and 100 mg/d Versus Placebo for the Treatment of Major Depressive Disorder: A Phase 4, Randomized Controlled Trial

Objective: To assess short-term efficacy and safety of desvenlafaxine 50 and 100 mg/d versus placebo for treating major depressive disorder (MDD). Assessment of sexual function was a secondary objective.

Method: Outpatients (≥ 18 years) who met criteria for MDD from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision and had screening and baseline 17-item Hamilton Depression Rating Scale (HDRS17) total scores ≥ 20 were randomly assigned to placebo or desvenlafaxine 50 or 100 mg/d in an 8-week study conducted from October 2011 to August 2012. The primary efficacy end point was change from baseline in HDRS17 total score at week 8, analyzed using a mixed-effects model for repeated measures. Sexual function was assessed using the Arizona Sexual Experiences Scale (ASEX).

Results: The safety population included 909 patients (intent-to-treat population, n = 886). Significantly greater improvement in adjusted mean HDRS17 total score from baseline to week 8 was observed for desvenlafaxine 50 mg (-11.28; P = .006) and desvenlafaxine 100 mg (-11.67; P < .001) compared with placebo (-9.71), with adjustment for multiplicity. In the ASEX total score analysis (n = 422), the treatment by gender interaction was not significant; thus, genders were combined for subsequent analyses. Comparisons for desvenlafaxine versus placebo for change from baseline in ASEX total and all item scores found P > .05, with no adjustment for multiplicity. Rates of sexual dysfunction based on ASEX were comparable among treatment groups.

Conclusions: These results support previous findings demonstrating antidepressant efficacy, safety, and tolerability of desvenlafaxine 50 and 100 mg/d versus placebo. Sexual function was comparable between desvenlafaxine and placebo.

Trial Registration: ClinicalTrials.gov identifier: NCT01432457