Background: The predictive value of early functional improvement for treatment success at week 8 was assessed in a pooled analysis in patients with major depressive disorder (MDD) treated with desvenlafaxine (administered as desvenlafaxine succinate) or placebo. Methods: Data were pooled from 7 double-blind studies (either published or submitted for publication) in adult patients with MDD randomly assigned to desvenlafaxine 50 mg/d or placebo. Patients with baseline Sheehan Disability Scale (SDS) score >12 (N=2156) had 4 levels of treatment success determined at week 8 (last observation carried forward), defined as: functional response (SDS ≤12), functional/depression response (SDS ≤12 and ≥50% improvement in 17-item Hamilton Rating Scale for Depression [HAM-D17] score), functional remission (SDS <7), and functional/depression remission (SDS <7 and HAM-D17 ≤7). Early improvement in SDS (week 2) was evaluated as a predictor of later functional response/remission using receiver operating characteristic analysis. Odds ratios (ORs) of the predictability of improvement thresholds were computed from a logistic regression model. Results: The proportion of patients achieving each level of treatment success was significantly greater for patients treated with desvenlafaxine (49%, 37%, 23%, 15%, respectively) vs placebo (38%, 25%, 17%, 10%; all P≤0.002). Early change in SDS was a highly significant predictor of functional response/remission (ORs, 0.958–0.976; all P<0.0001). The optimal thresholds for predicting functional response/remission ranged from 17% to 30% SDS improvement at week 2. Discussion: Patients’ early functional response to desvenlafaxine 50 mg/d may have clinical value in predicting treatment success. Research supported by Pfizer Inc.
Claudio Soares, MD, PhD, FRCPC; Jean Endicott, PhD; Matthieu Boucher, PhD; Rana Fayyad, PhD; Alesia Sadosky; Christine Guico-Pabia, MD, MBA, MPH