Pregabalin (Lyrica) Is First Drug Approved for Fibromyalgia

ROCKVILLE, Md., June 22 -- The FDA has approved pregabalin (Lyrica) for treatment of fibromyalgia.

The agency said that pregabalin, which was already approved for partial seizures and symptomatic relief of shingles and diabetic neuropathy, is the first drug to win an indication for fibromyalgia, a disorder characterized by pain, fatigue, and sleep problems.

But Steven Galson, M.D., M.P.H., director of the FDA's Center for Drug Evaluation and Research, cautioned that the drug was not a panacea because response to the drug was not universal.

In a pair of studies reported last month at the American Psychiatric Association meeting, the response rate varied from about 30% to 60%.

In November 2006, a preliminary report from one of those trials found that 63% of patients reported pain relief with the drug. (See ACR: Lyrica Shows Durable Effect In Fibromyalgia)

The FDA put it this way, "Two double-blind, controlled clinical trials, involving about 1,800 patients, support approval for use in treating fibromyalgia with doses of 300 mg or 450 mg per day."

The FDA estimated that three to six million Americans -- most of them middle-aged women -- have fibromyalgia.

There is, however, no clinical test to confirm a diagnosis. An exclusionary diagnosis is made after physical examination and symptom evaluation.

Management of the condition is additionally complicated by the finding that patients with fibromyalgia may experience pain differently than other patients, which may also affect response to medication. The pregabalin trials, for example, offer no mechanistic explanation for response.

The most common side effects of pregabalin include mild-to-moderate dizziness and sleepiness. Blurred vision, weight gain, dry mouth, and swelling of the hands and feet also were reported in clinical trials. The side effects appeared to be dose-related.

Pregabalin can impair motor function and cause problems with concentration and attention. The FDA said the agent could impair a patient's ability to drive.

Pregabalin is manufactured by Pfizer. The FDA said Pfizer has agreed to a post-marketing study of the drug in children with fibromyalgia and a study in breastfeeding women.