OBJECTIVES: Existing treatments for fibromyalgia have limited efficacy, and only a minority of individuals clinically respond to any single intervention. This study was a prospective, multicenter, randomized, double-blind, controlled clinical trial to evaluate the feasibility of alternating magnetic field therapy in fibromyalgia patients by comparing the Angel Touch device (AT-02) with a sham control (S-01). METHODS: Two sites enrolled 44 subjects with diagnosed fibromyalgia. After informed consent, subjects taking prohibited concomitant drugs underwent a washout period of two or more weeks. All subjects then began a one-week run-in period. Numerical rating scale (NRS) pain scores were collected without device intervention for one day, followed by S-01 application to four or more painful sites for 10 minutes at each site, twice daily for six days. Subjects were then randomized to AT-02 or S-01, applied to four or more painful sites for 10 minutes at each site, twice daily for eight weeks. NRS scores were obtained twice daily during the entire treatment period. RESULTS: The primary end point (change in NRS ± SD at week 8 vs baseline) was -0.94 ± 1.33 in the AT-02 group and -0.22 ± 1.38 in the S-01 group. A trend toward a between-group difference in eight-week NRS scores favored the AT-02 group (-0.73, 95% confidence interval = -1.56 to 0.11, P = 0.086). An adjusted repeated measure analysis detected a significant difference in NRS scores (P = 0.039). CONCLUSIONS: The reduction in NRS scores for AT-02 relative to sham was comparable to reductions observed in meta-analyses of fibromyalgia drug therapy. The unadjusted results and the persistence of the pain score reductions remain encouraging.