(286) Efficacy of duloxetine in patients with fibromyalgia: Pooled analysis of four placebo-controlled clinical trials

Abstract

Fibromyalgia (FM) is characterized by chronic widespread musculoskeletal pain, fatigue, mood disturbance, and functional impairment. This pooled analysis of 4 placebo-controlled, double-blind, randomized trials assessed the efficacy of duloxetine compared with placebo on pain reduction in patients with FM. Across all studies, 797 patients received duloxetine 60 mg/day or 120 mg/day (doses pooled) and 535 patients received placebo. Pain was assessed by the 24-hour average pain severity score on the Brief Pain Inventory (BPI); other efficacy measures included the Clinical Global Impressions of Severity (CGI-S), Patient Global Impressions of Improvement (PGI-I), 17-item Hamilton Depression Rating Scale (HAMD), Fibromyalgia Impact Questionnaire (FIQ) total score, Multidimensional Fatigue Inventory (MFI), pain interference items on the BPI, Sheehan Disability Scale (SDS), the Short Form-36 mental component scale (SF-36 MCS) and physical component scale (SF-36 PCS). Changes from baseline to endpoint (LOCF) for most of the above efficacy measures were analyzed using an analysis of covariance model. After 12 weeks of treatment, pain was significantly reduced in patients treated with duloxetine (p<.001) compared with placebo. In addition, duloxetine was superior to placebo on the CGI-S (p<.001), PGI-I (p<.001), FIQ total scores (p<.001), MFI mental fatigue score (p=.002); as well as improvement in depressive symptoms (p=.003). Treatment with duloxetine was also associated with significant improvement in functioning as assessed by SDS scores rating global functioning (p<.001), work/school (p=.018) and family life (p<.001); SF-36 MCS (p<.001) and PCS (p=.026), and pain interference scores (p<.001). The most common adverse events (≥5% or significantly more frequent) for duloxetine were: nausea, headache, dry mouth, insomnia, fatigue, constipation, diarrhea, dizziness, somnolence, hyperhydrosis, and decreased appetite. Results suggest that 12 weeks of treatment with duloxetine versus placebo was associated with significant reduction in pain severity, improvement in mood and mental fatigue, and improved functioning. Studies funded by Eli Lilly and Company. Fibromyalgia (FM) is characterized by chronic widespread musculoskeletal pain, fatigue, mood disturbance, and functional impairment. This pooled analysis of 4 placebo-controlled, double-blind, randomized trials assessed the efficacy of duloxetine compared with placebo on pain reduction in patients with FM. Across all studies, 797 patients received duloxetine 60 mg/day or 120 mg/day (doses pooled) and 535 patients received placebo. Pain was assessed by the 24-hour average pain severity score on the Brief Pain Inventory (BPI); other efficacy measures included the Clinical Global Impressions of Severity (CGI-S), Patient Global Impressions of Improvement (PGI-I), 17-item Hamilton Depression Rating Scale (HAMD), Fibromyalgia Impact Questionnaire (FIQ) total score, Multidimensional Fatigue Inventory (MFI), pain interference items on the BPI, Sheehan Disability Scale (SDS), the Short Form-36 mental component scale (SF-36 MCS) and physical component scale (SF-36 PCS). Changes from baseline to endpoint (LOCF) for most of the above efficacy measures were analyzed using an analysis of covariance model. After 12 weeks of treatment, pain was significantly reduced in patients treated with duloxetine (p<.001) compared with placebo. In addition, duloxetine was superior to placebo on the CGI-S (p<.001), PGI-I (p<.001), FIQ total scores (p<.001), MFI mental fatigue score (p=.002); as well as improvement in depressive symptoms (p=.003). Treatment with duloxetine was also associated with significant improvement in functioning as assessed by SDS scores rating global functioning (p<.001), work/school (p=.018) and family life (p<.001); SF-36 MCS (p<.001) and PCS (p=.026), and pain interference scores (p<.001). The most common adverse events (≥5% or significantly more frequent) for duloxetine were: nausea, headache, dry mouth, insomnia, fatigue, constipation, diarrhea, dizziness, somnolence, hyperhydrosis, and decreased appetite. Results suggest that 12 weeks of treatment with duloxetine versus placebo was associated with significant reduction in pain severity, improvement in mood and mental fatigue, and improved functioning. Studies funded by Eli Lilly and Company.