Efficacy and response time to sertraline versus fluoxetiae in the treatment of unipolar major depressive disorder

Background: Few studies have compared the treatment efficacy of the 2 selective serotonin reuptake inhibitors sertraline and fluoxetine. Method: A randomized, single-blind, parallelgroup study of 10 weeks' duration comparing the efficacy of sertraline, 50 mg/day; sertraline, 100 mg/day; and fluoxetine, 20 mg/day, was conducted in 44 psychiatric outpatients with DSM-IV unipolar major depressive disorder. Antidepressant dosages were doubled at 6 weeks for subjects who had not achieved remission. Primary outcome measurements included the 21-item Hamilton Rating Scale for Depression (HAM-D) and the Clinical Global Impressions-Improvement scale (CGI-I), with scores of ≤ 7 on the HAM-D and ≤ 2 on the CGI-I representing a positive treatment response, i.e., remission. Results: At 4 weeks, significant differences in rate of positive treatment response were noted, with 0% for sertraline, 50 mg; 46% for sertraline, 100 mg; and 31% for fluoxetine, 20 mg (p = .023). At 6 weeks, positive treatment response rates were 21%, 43%, and 31% for subjects taking 50 mg of sertraline, those taking 100 mg of sertraline, and those taking 20 mg of fluoxetine, respectively, with treatment groups no longer differing significantly from each other. In subjects for whom antidepressant dose was doubled at week 6, response rates at week 10 (4 weeks on increased dose) were 40% for sertraline, 100 mg; 43% for sertraline, 200 mg; and 55% for fluoxetine, 40 mg. Conclusion: Subjects taking sertraline, 100 mg, and fluoxetine, 20 mg, demonstrated an earlier treatment response compared with subjects taking sertraline, 50 mg. For patients without a positive response at 6 weeks, an increased antidepressant dose resulted in remission for a substantial proportion of patients when assessed 4 weeks later.