An Integrated Analysis of the Efficacy of Desvenlafaxine Compared with Placebo in Patients with Major Depressive Disorder

Introduction: To assess the efficacy of desvenlafaxine (administered as desvenlafaxine succinate) in outpatients with major depressive disorder. Methods: A meta-analysis of individual patient data was performed on the complete set of registration trials (nine randomized, double-blind, placebo-controlled 8-week studies) of desvenlafaxine. Patients received fixed (50, 100, 200, or 400 mg/day; n=1,342) or flexible doses (100-400 mg/day; n=463) of desvenlafaxine or placebo (n=1,108). The primary efficacy variable was the 17-item Hamilton Rating Scale for Depression (HAM-D-17); the primary intent to treat analyses used the last-observation-carried-forward method. Results: Significantly greater improvement with desvenlafaxine versus placebo on the HAM-D-17 total score was observed for the full data set (difference in adjusted means: -1.9; P<.001), each fixed-close group (all P<.001), and the flexible-dose group (P=.024). Overall rates of HAM-D-17 response (>= 50% decrease from baseline score: 53% vs 41%) and remiss on (HAM-D-17 <= 7: 32% vs 23%) were significantly greater for desvenlafaxine versus placebo (all P<.001). Discontinuation rates due to adverse events increased with dose (4% to 18%; placebo: 3%). Conclusion: Desvenlafaxine demonstrated short-term efficacy for treating major depressive disorder across the range of doses studied. No evidence of greater efficacy was observed with doses >50 mg/day; a strong dose-response effect on tolerability was observed.