Comparative efficacy and harms of duloxetine, milnacipran, and pregabalin in fibromyalgia syndrome

Duloxetine (DLX), milnacipran (MLN), and pregabalin (PGB) are the only drugs licensed by the US Food and Drug Administration (FDA) for fibromyalgia syndrome (FMS). Evidence on the comparative benefits and harms is still accruing. The authors searched MEDLINE, SCOPUS, Cochrane Central Register of Controlled Trials, and sought unpublished data from the databases of FDA, US National Institutes for Health, and Industry through May 2009 for randomized controlled trials. Outcomes of interest were symptom reduction (pain, fatigue, sleep disturbance, depressed mood, reduced health-related quality of life), and adverse events. 17 studies with 7,739 patients met the inclusion criteria. The 3 drugs were superior to placebo except DLX for fatigue, MLN for sleep disturbance, and PGB for depressed mood. Adjusted indirect comparisons indicated no significant differences for 30% pain relief and dropout rates due to adverse events between the 3 drugs. Significant differences in average symptom reduction were found: DLX and PGB were superior to MLN in reduction of pain and sleep disturbances. DLX was superior to MLN and PGB in reducing depressed mood. MLN and PGB were superior to DLX in reducing fatigue. The risk of headache and nausea with DLX and MLN was higher compared with PGB. The risk of diarrhea was higher with DLX compared to MLN and PGB. There is evidence for the short-term (up to 6 months) efficacy of DLX, MLN, and PGB. Differences with regard to the occurrence of the key symptoms of FMS and to drug-specific adverse events may be relevant for the choice of medication.

Perspective: This article presents comparative data on the efficacy and harms of duloxetine, milnacipran, and pregabalin in fibromyalgia syndrome. The results can help clinicians in choosing medication since the 3 drugs have different effects on the key symptoms of fibromyalgia syndrome and differences in side effects, contraindications, and warnings.