A Double-Blind, Multicenter Trial Comparing Duloxetine With Placebo in the Treatment of Fibromyalgia Patients

Objective. To assess the efficacy and safety of duloxetine, a serotonin and norepinephrine reuptake inhibitor, in subjects with primary fibromyalgia, with or without current major depressive disorder. Methods. This study was a randomized, double-blind, placebo-controlled trial conducted in 18 outpa-tient research centers in the US. A total of 207 subjects meeting the American College of Rheumatology criteria for primary fibromyalgia were enrolled (89 % female, 87 % white, mean age 49 years, 38 % with current major depressive disorder). After single-blind placebo treat-ment for 1 week, subjects were randomly assigned to receive duloxetine 60 mg twice a day (n 104) or placebo (n 103) for 12 weeks. Co–primary outcome measures were the Fibromyalgia Impact Questionnaire (FIQ) total score (score range 0–80, with 0 indicating no impact) and FIQ pain score (score range 0–10). Second-ary outcome measures included mean tender point pain threshold, number of tender points, FIQ fatigue, tired-ness on awakening, and stiffness scores, Clinical Globa