Bupropion extended release compared with escitalopram: effects on sexual functioning and antidepressant efficacy in 2 randomized, double-blind, placebo-controlled studies

Abstract

Objective: To compare the effects on sexual functioning and the antidepressant efficacy of once-daily bupropion extended release (XL) and escitalopram in adults with major depressive disorder (MDD).

Method: Adult outpatients with moderate to severe DSM-IV-defined MDD and normal sexual functioning were randomly assigned to receive bupropion XL (300-450 mg/day; N = 276), escitalopram (10-20 mg/day; N = 281), or placebo (N = 273) for up to 8 weeks in 2 identically designed, randomized, double-blind, parallel-group studies (study 1 conducted from February 6, 2003, to June 10, 2004; study 2 conducted from January 21, 2003, to June 15, 2004). Data were analyzed prospectively for each study individually, and pooled data were analyzed retrospectively.

Results: In both the individual studies and the pooled dataset, the incidence of orgasm dysfunction at week 8 (primary endpoint) and the incidence of worsened sexual functioning at the end of the treatment period were statistically significantly lower with bupropion XL than with escitalopram (p < .05), not statistically different between bupropion XL and placebo (p > or = .067), and statistically significantly higher with escitalopram than with placebo (p < or = .001). The percentages of patients with orgasm dysfunction at week 8 in study 1, study 2, and the pooled dataset, respectively, were 13%, 16%, and 15% with bupropion XL; 32%, 29%, and 30% with escitalopram; and 11%, 8%, and 9% with placebo. The respective percentages of patients with worsened sexual functioning at the end of the treatment period were 18%, 22%, and 20% with bupropion XL; 37%, 34%, and 36% with escitalopram; and 14%, 16%, and 15% with placebo. Mean changes in Changes in Sexual Functioning Questionnaire scores for all domains at week 8 were statistically significantly worse for escitalopram compared with bupropion XL (p < or = .05). Separation from placebo could not be established at a statistical .05 level for bupropion on 17-item Hamilton Rating Scale for Depression (HAM-D-17) total score. However, escitalopram showed statistical superiority to placebo on HAM-D-17 total score in one of the 2 studies and in the pooled data. Bupropion XL did not statistically differ from escitalopram with respect to mean change in HAM-D-17 total score, HAM-D-17 response or remission rates, percentage of patients much or very much improved on Clinical Global Impressions-Improvement scale scores, or mean changes in the Hospital Anxiety and Depression (HAD) scale total score or Clinical Global Impressions-Severity of Illness scale score at week 8.

Conclusions: Bupropion XL had a sexual tolerability profile significantly better than that of escitalopram with similar HAM-D-17 remission rates and HAD total scores in patients with MDD.