Efficacy and safety of selegiline transdermal system (STS) for the atypical subtype of major depressive disorder: pooled analysis of 5 short-term, placebo-controlled trials

Objective The objective of the present study is to investigate the efficacy and safety of the selegiline transdermal system (STS) in major depressive disorder (MDD) with atypical features. Methods This was a post-hoc analysis of 5 short-term trials. The atypical subtype was defined as the presence of at least 1 item with a score of 2 or greater from items 22–26 on the 28-item Hamilton Depression Rating Scale (HAMD-28), and a maximum score of 1 point for items 6 (insomnia late), 12 (somatic symptoms, gastrointestinal), and 16 (loss of weight) to exclude vegetative features of melancholic depression. The mean changes of HAMD-28 total score from baseline to the endpoint (response rate defined as ≥50% reduction in HAMD-28 scores and remission rate defined as ≤10 HAMD-28 total score at the treatment endpoint) were compared between atypical and nonatypical groups. Results In this analysis, 352 subjects (STS = 168 vs placebo = 184) met the definition of atypical subtype at baseline. STS (n = 641) significantly decreased HAMD-28 total score compared with placebo (n = 648) from beginning to end of treatment (–10.7 ± 9.3 vs –9.4 ± 9.3; p = 0.014). STS showed comparable efficacy in patients with the atypical subtype compared with the nonatypical subtype for placebo-subtracted mean change in HAMD-28 total score (–2.11 ± 1.01 vs. –1.0 ± 0.60; p = 0.34), odds ratio (OR) for response (1.41 vs 1.23, p = 0.62), and OR for remission (1.77 vs 1.18, p = 0.22). Conclusion STS appears to be comparably efficacious and tolerable in atypical and nonatypical subtypes of MDD. Adequately powered, controlled, clinical trials are necessary to confirm our findings.