METHODS: A total of 148 depressive patients receiving escitalopram 10-20 mg/day were genotyped for 5HTTLPR and rs25531 polymorphisms. Clinical assessment was done at baseline and after 4, 8, and 12 weeks using the 17-item Hamilton Depression Rating Scale (HDRS-17), Montgomery-Asberg Depression Rating Scale (MADRS), and Clinical Global Impression Scale (CGI). At the end of week 12, patients were defined as responders and non-responders based on HDRS17 and MADRS scores. Chi-square test and logistic regression analysis were performed to investigate the genotypic influence on treatment response. Comparison of continuous variables among different groups was done using Student's t test or one-way ANOVA.

METHODS: Elderly outpatients aged at least 65 years with a primary diagnosis of moderate to severe episode of recurrent MDD were recruited by psychiatrists in 44 clinical centers in 10 countries from October 2013 to January 2016. Patients were randomly assigned to receive tianeptine (n = 105), placebo (n = 107), or escitalopram (n = 99) for 8 weeks. The primary outcome measure was the 17-item Hamilton Depression Rating Scale (HDRS₁₇) total score.

RESULTS: Tianeptine improved depressive symptoms, as evaluated by the HDRS₁₇ total score in terms of absolute change from baseline (week 0) to week 8 (placebo-tianeptine difference [SE] of 3.84 [0.85] points, P < .001, using a last-observation-carried-forward approach) and response to treatment (tianeptine: 46.7%; placebo: 34.0%, estimate [SE] = 12.70% [6.70], P = .06). A sensitivity analysis using a mixed model for repeated measures confirmed the main results on HDRS total s​core. The placebo-tianeptine difference (SE) was 0.66 (0.15) for Clinical Global Impressions-Severity of Illness (95% CI, 0.37 to 0.96; P < .001) and 0.57 (0.14) for Clinical Global Impressions- Improvement (95% CI, 0.30 to 0.83; P < .001). Positive results were also obtained with the active control escitalopram (HDRS₁₇ total score placebo-escitalopram difference of 4.09 ± 0.86 points, P < .001), therefore validating the sensitivity of the studied population. Tianeptine was well tolerated, with only minimal differences in tolerability from placebo.

CONCLUSIONS: The present study provides robust evidence that an 8-week treatment period with tianeptine 25-50 mg is efficacious and well tolerated in depressed patients aged 65 years or older.