Jazz Pharmaceuticals Inc, Palo Alto, Calif, and UCB, Brussels, Belgium, have completed the first of two phase 3 pivotal clinical trials of sodium oxybate for the treatment of fibromyalgia with the drug achieving its primary endpoints. The phase 3 trial demonstrated that sodium oxybate significantly decreased pain and fatigue and improved daily function in patients with fibromyalgia.

“Achieving positive sodium oxybate data in fibromyalgia from this phase 3 clinical trial is an exciting milestone for Jazz Pharmaceuticals, and supports our commitment to developing products that can improve outcomes for patients with serious medical conditions,” says Samuel Saks, MD, chief executive officer of Jazz Pharmaceuticals.

The 14-week randomized, double-blind study included 548 adult patients with fibromyalgia who were assigned randomly to one of three treatment options: sodium oxybate 4.5 g/night, sodium oxybate 6 g/night, or placebo. The primary outcome measure was the proportion of patients who achieved at least 30% reduction in pain from baseline to endpoint based on the Pain Visual Analog Scale.

Of the patients receiving sodium oxybate treatment, 46.2% of patients on 4.5 g /night and 39.3% of patients on 6 g/night reported at least a 30% reduction in pain, compared with 27.3% of patients on placebo. These results were highly statistically significant. Patients receiving sodium oxybate also reported a significant improvement in fatigue.