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Wyeth faces battle over venlafaxine


A pharmaceutical firm is facing a financial hit over the patent for its antidepressant Effexor (venlafaxine), experts claim.

Wyeth is currently the exclusive seller of extended-release Effexor in the US until July 2010 after it won a battle over the patent back in 2005.

But the New Jersey-based firm is under threat from Sun Pharmaceutical Industries, a generics manufacturer in India, which has applied for Food and Drug Administration (FDA) approval to sell venlafaxine, but with an important difference – it is an extended-release tablet, and not a capsule.

The patent for venlafaxine runs out in June 2008, but the capsule formulation protection expires later.

Sun hopes its different formulation will allow it to sidestep Wyeth’s patent rights, and Wyeth has already announced it will not sue for patent infringement.

Deutsche Bank analyst Barbara Ryan said of the move: “It’s not helpful. The issue is Wyeth has tremendous exposure to generic competition between now and 2010, and a lot of arrows are pointed at their two major drugs, Protonix and Effexor.”

Experts believe the Sun version of Effexor XR could take up to 15% of the market share for the drug, the equivalent of a $500m loss in annual sales for Wyeth.

Copyright © PA Business 2007


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