A double-blind, randomized, placebo-controlled trial of once-daily venlafaxine extended release (XR) and fluoxetine for the treatment of depression

Background: We compared the efficacy and tolerability of venlafaxine XR wit h that of fluoxetine in a multicenter, randomized, double-blind, placebo-co ntrolled study in depressed outpatients, Methods: Outpatients, 18 years and older, who met DSM-IV criteria for major depressive disorder were included (n = 301 randomized; 232 completed). Patients were randomly:assigned to ei ght weeks of treatment with either venlafaxine XR 75-225 mg/day (n = 100), fluoxetine 20-60 mg/day (n = 103), or placebo (n = 98), The primary efficac y outcome measures were the final ratings on the Hamilton Rating Scale for Depression (HAM-D-21) total score, HAM-D-21 depressed mood item, Montgomery -Asberg Depression Rating Scale total score, and Clinical Global Impression s Scale. Results: Withdrawal from the study due to adverse events occurred in 6% of the patients in the venlafaxine XR group and 9% of the patients in the fluoxetine group. Patients treated with venlafaxine XR, but only rarel y those treated with fluoxetine, had statistically significant improvements in their depression ratings compared with placebo at the end of the study. The percentages of patients who achieved full remission of their depressio n (HAM-D-21 total score less than or equal to 7) at the end of treatment we re 37%, 22% and 18% for the venlafaxine XR, fluoxetine and placebo groups, respectively. The differences in remission rates between venlafaxine XR and the other groups were statistically significant (p < 0.05). Limitations: T he superior remission outcome observed with venlafaxine XR treatment needs to be replicated in additional studies. Conclusion: Venlafaxine XR is a wel l-tolerated and efficacious treatment for depression. The results of this s tudy suggest that venlafaxine XR is as well-tolerated as fluoxetine but may have some efficacy advantages over fluoxetine, (C) 1999 Elsevier Science B .V. All rights reserved.