A 1-year safety and efficacy study of duloxetine in patients with fibromyalgia.

OBJECTIVE

Evaluate the efficacy and safety of duloxetine at doses up to 120 mg once daily in patients with fibromyalgia.

METHODS

This was a phase 3, 60-week study, which included an 8-week open-label period followed by a 52-week, randomized, double-blind period. Patients received duloxetine 30 mg daily for 1 week and duloxetine 60 mg daily for 7 weeks and were then randomized to receive either 60 or 120 mg daily (1:2 ratio).

RESULTS

Enrolled patients (N=350, 95.7% female) exhibited moderate disease symptoms at study entry (Brief Pain Inventory average pain=6.7, Clinical Global Impression of Severity=4.1, and Patient's Global Impression of Severity=4.1). Significant pain reduction in patients was observed during the open-label study phase. This pain reduction continued during the 52-week double-blind study phase, as demonstrated by additional mean decreases in the Brief Pain Inventory average pain score within both duloxetine groups. The most common (> or =15%) treatment-emergent adverse events (overall phase) were nausea, headache, insomnia, dizziness, constipation, and dry mouth. Seventy-four (21.1%) patients reported adverse events as a reason for discontinuation [most common (>1%) were insomnia, vomiting, diarrhea, dizziness, and nausea]. The mean change (SD) in sitting systolic blood pressure (mm Hg) was -0.1 (14.4), in sitting diastolic blood pressure was -0.2 (9.6), in sitting pulse rate was 1.9 (10.4) bpm, and in weight was 0.7 (4.3) kg.

CONCLUSIONS

The profile of duloxetine for the long-term treatment of fibromyalgia was consistent with that seen in other indications for which the drug is currently marketed.