Pfizer (NYSE:PFE) reported this morning that advanced studies of a drug treating fibromyalgia performed better than placebos, bringing the drug a step closer to being declared effective in once-a-day doses. According to the press release, fibromyalgia affects more than 5 million Americans.

The drug, which the $177 billion pharmaceutical giant markets under the brand name Lyrica, first received the FDA's green light in 2004 and is approved to treat five indications, mostly in the "therapeutic area of pain."

According to Pfizer's most recent annual report, Lyrica was one of only 12 of the company's biopharmaceutical products to have more than $1 billion in sales in 2011. Lyrica sales jumped 21% in 2011 from the previous year. The drug goes off patent in the U.S. in 2018.

Pfizer stock was up nearly 1.2% today.

John Divinehas no positions in the stocks mentioned above. You can follow him on Twitter, @divinebizkid, and on Motley Fool CAPS, @TMFDivine.

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