The purpose of this study is to determine if DVS-233 is safe and effective in the treatment of pain and other symptoms of fibromyalgia syndrome.

Inclusion Criteria:

• Fibromyalgia according to 1990 American College of Rheumatology (ACR) criteria

Exclusion Criteria:

• Other painful conditions that may make results difficult to interpret.
• Treatment with other drugs for fibromyalgia with 14 days of study start or during the study.