The aim of this study was to assess the efficacy and safety of sertraline compared with placebo in a good clinical practice trial conducted with major depressive disorder patients naive to selective serotonin reuptake inhibitors.
This was a 10-week randomized, multicenter, placebo-controlled, double blind, superiority trial. Adult patients diagnosed with major depressive disorder (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria), total score of 19 to 36 in the 17-item Hamilton Depression Rating Scale (HAMD-17), were randomly allocated to sertraline (n = 39) or placebo (n = 38). Each patient received a fixed dose of sertraline 50 mg/d or placebo for 4 weeks. Afterward a flexible dose up to 200 mg/d was allowed if needed. The primary efficacy end point was clinical response defined as 50% score reduction in HAMD-17 at 10 weeks relative to baseline. Supplementary analysis was performed on HAMD-17 score change from baseline.
The clinical response favored sertraline (72% vs 32%; relative risk, 2.27; 95% confidence interval, 1.37–3.78; P = 0.0006). A linear mixed model showed arm × time interaction was significant (likelihood ratio test χ2 on 7 df = 48.42, P < 0.0001). The HAMD-17 change score favored sertraline from week 8 onwards. The most frequent adverse events in the sertraline arm were headache, diarrheas, and weight loss.
In this trial, the benefit of sertraline compared with placebo appeared later than usual. The therapeutic process with a close doctor-patient relationship throughout the trial and the effect expectancy due to a new treatment might explain the response delay.
Trial registration: RPCEC, ID no. 00000128.