Results
±
ADVERSE EVENTS, ADVERSE EVENT
Out of the 74 screened patients, 65 were recruited and randomly assigned to sertraline and agomelatine (N = 33) or sertraline and placebo (N = 32) groups. As presented in Figs. 
Demographic characteristics of the participants
Flowchart of the participants enrolled in the trialThe baseline Y-BOCS scores were not significantly different between the groups in total (MD (95% CI) = 0.270 (-1.062, 1.602) (P = 0.8403)), the obsession subscale (MD (95% CI) = 1.060 (0.204, 1.916,) (P = 0.2214)) and compulsion subscale (MD (95% CI) = 0.790 (-0.168, 1.748) (P = 0.4136)) (Table 
Baseline Y-BOCS scores of the patientsTotal Y-BOCS scores significantly dropped in both groups, slightly more in the placebo group. The score changes from baseline in the agomelatine group at weeks 4, 8 and 12 were MD (95% CI) = 3.04 (1.63, 4.44) (P = 0.03), MD (95% CI) = 7.75 (6.49, 9.00) (P < 0.001), and MD (95% CI) = 12.25 (11.00, 13.49) (P < 0.001), respectively. Furthermore, score changes from baseline in the placebo group at weeks 4, 8, and 12 were MD (95% CI) = 4.54 (1.21, 9.98) (P = 0.03), MD (95% CI) = 8.50 (6.65, 4.443) (P < 0.001), and MD (95% CI) = 12.46 (6.65, 15.74) (P < 0.001), respectively (Fig. The mean difference between the two groups at weeks four (MD (95% CI) = 1.770 (1.417) (P = 0.21)), eight (MD (95% CI) = 1.020 (1.413) (P = 0.47)) and twelve (MD (95% CI) = 0.480 (-1.23, 2.19) (P = 0.78)) were not statistically significant. Also, repeated-measures analysis did not reveal a significant effect of time (Greenhouse-Geisser F (2.176, 104.426) = 0.546, P = 0.59).
The mean (± standard deviation) Y-BOCS scores of weeks 4, 8, and 12, and their comparison with the baseline scores (95% CI)
Comparison of the total Y-BOCS score changes between the two groups during the course of trialY-BOCS obsession subscale score changes from baseline in the agomelatine group at weeks 4, 8 and 12 were MD (95% CI) = 0.91 (0.15, 1.66) (P = 0.23), MD (95% CI) = 2.91 (2.19, 3.66) (P = 0.0002), and MD (95% CI) = 5.04 (4.19, 5.88) (P < 0.001), respectively. Score changes from baseline in the placebo group at weeks 4, 8 and 12 were MD (95% CI) = 1.81 (0.79, 2.8) (P = 0.07), MD (95% CI) = 3.35 (2.31, 4.38) (P = 0.002), and MD (95% CI) = 5.00 (3.84, 6.16) (P < 0.001), respectively (Fig. At week 4, the Y-BOCS scores significantly dropped in the placebo group (MD (95% CI) = 1.960 (0.948) P = 0.04However, the mean differenced at weeks eight (MD (95% CI) = 1.500 (0.947) (P = 0.11)) and twelve (MD (95% CI) = 1.020 (-0.15, 2.19) (P = 0.38)) were not statistically significant (Fig. 
Comparison of Y-BOCS score changes between the two groups during the course of trialThe Y-BOCS compulsion subscale score changes from baseline at weeks 4, 8 and 12 of the study in the agomelatine group were MD (95% CI) = 2.13 (1.08, 3.17) (P = 0.04), MD (95% CI) = 4.83 (3.94, 5.72) (P < 0.0001), and MD (95% CI) = 7.21 (6.34, 8.07) (P < 0.001), respectively. And in the placebo group, the score changes from baseline at weeks 4, 8 and 12 were MD (95% CI) = 2.73 (1.79, 3.66) (P = 0.005), MD (95% CI) = 5.15 (4.20, 6.09) (P < 0.001), and MD (95% CI) = 7.460 (6.50, 8.42) (p-value < 0.001), respectively (Fig. The mean difference between the two groups at weeks four (MD (95% CI) = 0.190 (1.021) (p-value = 0.85)), eight (MD (95% CI) = 0.470 (0.884) (p-value = 0.59)) and twelve (MD (95% CI) = 0.540 (-0.34, 1.42) (P = 0.54)) were not significantly different (Table Additionally, no significant difference was detected via repeated-measures analysis (Huyn-Feldt F (2.394, 114.931) = 0.165, P = 0.88).
Comparison of Y-BOCS score changes between the two groups during the course of trialHigh rates of LFTs were not detected in any of the patients.Adverse events were recorded during the study and were characterized as transient and non-severe, with no cases necessitating treatment discontinuation. The frequency of side effects was not significantly different between the groups (Table 
Comparison of the frequency of adverse events between the two groups (N, %)