Valeant Pharmaceuticals

(VRX)

said Thursday it has received U.S. clearance to begin marketing a treatment for Parkinson's disease.

The Food and Drug Administration's endorsement of the drug Zelapar concludes a

protracted process for Valeant, who submitted the drug for approval in April 2002.

Zelapar helps relieve symptoms of Parkinsons's, a progressive neurological disorder. The FDA approved the once-daily tablet as an adjunct therapy in patients receiving stronger drugs, levodopa or carbidopa. Zelapar will be used by patients who respond poorly to these drugs, helping them during the day when the other drugs wear off.

Zelapar is a version of selegiline, a compound used in treating

depression and Parkinson's.

In May,

Teva Pharmaceutical Industries

(TEVA) - Get Report

received FDA clearance for its Parkinson's drug Azilect. The drug, which also endured a long regulatory review, is

a once-a-day pill that can be used as a single therapy for patients in early stages of the disease or in combination with levodopa for moderate-to-severe forms of the disease.

Both Zelapar and Azilect belong to a class of drugs known as MAO inhibitors.

Zelapar uses a new delivery system that enables the tablet to dissolve quickly in the mouth, providing a "more active drug at a lower dose," the company says. Valeant, of Costa Mesa, Calif., also sells Tasmar for Parkinson's. Tasmar, known as a COMT inhibitor, is used an adjunct therapy with stronger drugs for patients with severe Parkinson's.

"With more than 1.5 million Americans with Parkinson's disease, and 60,000 new cases diagnosed each year, having new treatment options available to help manage the symptoms associated with the disease are critical," said Timothy Tyson, president and CEO of Valeant.

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