Duloxetine in the Treatment of Major Depressive Disorder: Comparisons of Safety and Efficacy in U.S. Hispanic and Majority Caucasian Patients

Roberto Lewis-Fernández, M.D.; Carlos Blanco, M.D., Ph.D.;Craig H. Mallinckrodt, Ph.D.; Madelaine M. Wohlreich, M.D.;John G. Watkin, D.Phil.; and John M. Plewes, M.D.

Objective: To evaluate new pharmacotherapies for the treatment of major depressive disorder (MDD) in Hispanic Americans, the largest ethnic minority group in the United States.

Method: Efficacy and safety data were pooled from 7 double-blind, placebo-controlled clinical trials of duloxetine conducted from February 1999 through November 2002. English-speaking patients (aged >= 18 years) meeting DSM-IV criteria for MDD received duloxetine (40-120 mg/day; Hispanic, N = 58; Caucasian, N = 748) or placebo (Hispanic, N = 62; Caucasian, N = 594) for up to 9 weeks. Efficacy measures included the 17-item Hamilton Rating Scale for Depression (HAM-D-17) total score, HAM-D-17 subscales, the Clinical Global Impressions-Severity of Illness scale, the Patient Global Impression of Improvement scale, and the Visual Analog Scales for pain. Safety was assessed using discontinuation rates, treatment-emergent adverse events, vital signs, and laboratory analyses. Three sets of data were analyzed using different pooling strategies, including exploratory analyses with 470 subjects (Hispanic, N = 51; Caucasian, N = 419) receiving the recommended dose of 60 mg.

Results: No evidence for a differential effect of duloxetine in Hispanic and Caucasian patients was found in efficacy outcomes. Discontinuation rates due to adverse events among duloxetine-treated patients were 14.0% for Hispanics and 17.0% for Caucasians, compared with 3.2% and 5.7%, respectively, for placebo-treated patients (p = .671). The type of adverse events and their individual rate of occurrence did not differ significantly between Hispanic and Caucasian patients. Mean changes from baseline for pulse, blood pressure, weight, and laboratory analytes were small and showed no significant differences between Hispanic and Caucasian patients.

Conclusion: In this analysis of pooled data, no evidence for a differential effect of duloxetine in Hispanic and majority Caucasian patients was found in efficacy or safety outcomes.

(J Clin Psychiatry 2006;67:1379-1390)

Received Jan. 11, 2006; accepted June 5, 2006. From Columbia University College of Physicians & Surgeons, New York State Psychiatric Institute, New York, N.Y. (Drs. Lewis-Fernández and Blanco); and Lilly Research Laboratories, Eli Lilly and Co., Indianapolis, Ind. (Drs. Mallinckrodt, Wohlreich, Watkin, and Plewes).

Presented in part as a poster session at the 157th annual meeting of the American Psychiatric Association, May 1-6, 2004, New York, N.Y.

Sponsored by Eli Lilly and Co., Indianapolis, Ind. Supported by New York State Psychiatric Institute (Drs. Lewis-Fernández and Blanco) and by NIH grant DA 00482 (Dr. Blanco). All of the authors participated in the decision to publish the data.

Dr. Lewis-Fernández is a member of the Multicultural Advisory Board for Eli Lilly. Dr. Mallinckrodt is an employee of and a stock shareholder in Eli Lilly. Dr. Wohlreich is an employee of and a stock shareholder in Eli Lilly. Dr. Watkin is an employee of Eli Lilly. Dr. Plewes is an employee of and a stock shareholder in Eli Lilly. Dr. Blanco reports no additional significant commercial or other relationships relevant to the subject of this article.

The authors gratefully acknowledge the comments of Michael R. Liebowitz, M.D.

Corresponding author and reprints: Roberto Lewis-Fernández, M.D., Hispanic Treatment Program, New York State Psychiatric Institute, Rm. 3200 (#69), New York, NY 10032(e-mail: rlewis@nyspi.cpmc.columbia.edu).