Safety and efficacy of esreboxetine in patients with fibromyalgia: A 14-week, randomized, double-blind, placebo-controlled, multicenter clinical trial Arthritis & Rheumatism, 04/26/2012

Arnold LM et al. – Esreboxetine was generally well tolerated and associated with significant improvements in pain, Fibromyalgia Impact Questionnaire (FIQ), Patient Global Impression of Change (PGIC), and fatigue scores compared with placebo. The lack of a dose–response relationship in both the efficacy and safety analyses suggests that 4–mg/d esreboxetine would offer clinical benefit with the least risk of drug exposure.

• Patients meeting American College of Rheumatology criteria for fibromyalgia were randomized to receive 4– (n = 277), 8– (n = 284), or 10–mg/d (n = 283) esreboxetine, or matching placebo (n = 278), for 14 weeks.
• Primary efficacy outcomes were weekly mean pain score and Fibromyalgia Impact Questionnaire (FIQ) total score at week 14.
• Secondary efficacy measures included Patient Global Impression of Change (PGIC), Global Fatigue Index (GFI), and 36–item Short–Form Health Survey (SF–36; Physical Functioning scale only) scores at week 14.
• Esreboxetine's safety profile was evaluated based on adverse events and other safety measures.

• All doses of esreboxetine demonstrated statistically significant improvements over placebo on pain (P ≤ 0.025), FIQ (P ≤ 0.023), and PGIC (P ≤ 0.007).
• Additionally, the 4– and 8–mg/d esreboxetine demonstrated statistically significant improvements over placebo on the GFI (P = 0.001).
• No significant improvements over placebo were evident for any dose of esreboxetine on the SF–36 Physical Functioning scale.
• Adverse events were mostly mild to moderate in severity; insomnia, constipation, dry mouth, nausea, dizziness, hot flush, headache, hyperhidrosis, and palpitations were reported most frequently.