Venlafaxine vs. fluoxetine in postmenopausal women with major depressive disorder: an 8-week, randomized, single-blind, active-controlled study

Background: In the population of postmenopausal patients with major depressive disorder (MDD), the superiority of serotonin-norepinephrine reuptake inhibitors (SNRIs) over selective serotonin reuptake inhibitors (SSRIs) has not yet been definitively proven. Consequently, a direct comparison of the efficacy of SSRIs and SNRIs in the treatment of postmenopausal depression could provide relevant data. The aim of this study was to compare the efficacy and safety of venlafaxine vs. fluoxetine in the treatment of postmenopausal MDD.

Methods: This was an 8-week, multicenter, randomized, single-blind, active-controlled trial conducted at a psychiatric hospital (Beijing Anding Hospital) and a general hospital (Beijing Chaoyang Hospital) between April 2013 and September 2017. The primary outcome measure was improving depressive symptoms (Hamilton Depression Rating Scale (HAMD-24) score). The secondary outcomes included the change of HAMD-24 anxiety/somatization factor score and Clinical Global Impressions-Improvement (CGI-I) response rate. Safety was assessed by treatment-emergent adverse events (TEAEs) and laboratory tests. Efficacy was analyzed by using the full analysis set (FAS) following the modified intention-to-treat (mITT) principle. The primary endpoint measurements were analyzed using a mixed-effect model for repeated measures (MMRM) model with patients as a random-effect factor, treatment group as the independent variable, time as a repeated measure, and baseline covariates, using a first-order ante dependence covariance matrix.

Results: A total of 184 women were randomized. The full analysis set (FAS) included 172 patients (venlafaxine, n = 82; fluoxetine, n = 90). Over the 8-week study period, the reduction in HAMD-24 scores was significant (P < 0.001) in both groups, while a significantly greater decline from baseline was observed in the venlafaxine group compared with the fluoxetine group (least-squares mean difference [95% CI]: - 2.22 [- 7.08, - 0.41]), P = 0.001). The baseline-to-week-8 least-squares mean change of the anxiety/somatization factor scores, CGI-I response rate were greater in the venlafaxine group than in the fluoxetine group (all P < 0.05). The most frequent TEAEs (≥5%) in both groups were nausea, somnolence, dizziness, headache, and dry mouth. There was no significant difference in the incidence of adverse events between the two groups.

Conclusion: Venlafaxine was well tolerated and compared to fluoxetine, it led to a greater improvement in the treatment of postmenopausal MDD.

Trial registration: Clinical Trials. gov #NCT01824433 . The trial was registered on April 4, 2013.