Double-blind, comparative study of milnacipran and paroxetine in Japanese patients with major depression

Abstract

Kunitoshi Kamijima,1 Shinji Hashimoto,2 Eiichi Nagayoshi,2 Tsukasa Koyama3 1International University of Health and Welfare, Tochigi, 2Asahi-kasei Pharma Corporation, Tokyo, 3Ohyachi Hospital, Sapporo, Japan Background and methods: A double-blind, parallel-group, controlled study was performed to investigate if milnacipran was noninferior to paroxetine in terms of improvement in symptoms of depression in Japanese patients with major depressive disorders in a fixed-dose design. The efficacy and safety of milnacipran 200 mg/day were also assessed in comparison with those at the standard dose of 100 mg/day. Results: Changes in 17-item Hamilton depression rating scale (HAM-D) total score (mean ± standard deviation) for group M1 (milnacipran 100 mg/day), group M2 (milnacipran 200 mg/day), and group PX (paroxetine 30 or 40 mg/day) were -12.9 ± 5.8, -12.8 ± 6.1, and -13.1 ± 6.2, respectively, and the estimated differences in total score for group PX (Dunnett's 95% simultaneous confidence interval) were 0.1 (-1.1 to 1.3) for group M1 and 0.3 (-0.9 to 1.5) for group M2. The noninferiority of groups M1 and M2 to group PX was thus confirmed, because the upper confidence limit of differences between groups M1 and PX and between groups M2 and PX was less than 2.0. The estimated mean difference of change in HAM-D total score (95% confidence interval) between groups M2 and M1 was 0.2 (-0.9 to 1.2), indicating a comparable change in total score for both groups. The incidence of treatment-related adverse events was 71.7% for group M1, 68.8% for group M2, and 69.3% for group PX, indicating no significant difference between the three groups. Conclusion: These results demonstrate that milnacipran 100 mg/day and 200 mg/day is not inferior to paroxetine in terms of efficacy and safety. Keywords: milnacipran, paroxetine, depression, noninferiority, Japan