Pfizer ( PFE) said Monday that the European Union has approved the drug Lyrica as a treatment for generalized anxiety disorder.

The EU's clearance enables Pfizer to expand the drug's uses, a process that has taken longer than the company had hoped.

Although Lyrica is approved for several diseases and conditions in the U.S. and in foreign markets, the Food and Drug Administration rejected Pfizer's application in mid-2004 for treating generalized anxiety disorder.

Pfizer continues to talk with the FDA about Lyrica as a treatment for the condition, a company spokeswoman said.

Lyrica has been approved in the U.S. for treating epileptic seizures and nerve pain related to diabetes and shingles. The drug is sold in more than 60 countries for various pain and seizure treatments.

Pfizer says clinical trials show Lyrica relieves generalized anxiety disorder symptoms such as depression, excessive worry and panic, as well as headaches and muscle pain. The most common side effects are dizziness and drowsiness. Pfizer says anxiety disorder can affect 5% of the population at some point.

Lyrica is Pfizer's follow-up to Neurontin, a big-selling, multiuse drug that has succumbed to generic competition. Neurontin's worldwide sales dropped to $639 million last year from $2.7 billion in 2004. Lyrica had $291 million in sales last year, with foreign markets accounting for 62%.

Pfizer received conditional approval in 2004 from the FDA for three Lyrica uses -- nerve pain associated with diabetes, nerve pain associated with shingles and epileptic seizures.

Lyrica later gained formal clearance but didn't reach the U.S. market until September 2005 because the Drug Enforcement Administration was reviewing it as a controlled substance. Lyrica is a Class V drug, meaning it exhibits the least risk for abuse.

Pfizer's stock was off 25 cents, or 1%, to $25.77

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