Wyeth Sues Lupin to Block Generic Effexor CR

In its ongoing battle to block generic Effexor, Wyeth Pharmaceuticals has sued generic firm Lupin Pharmaceuticals for patent infringement.

In a lawsuit filed in the U.S. District Court for the District of Maryland, Wyeth alleged that the generic version of its antidepressant drug made by Lupin infringes on three of seven patents covering Effexor controlled-release capsules.

Wyeth is suing to protect the '120, '171 and '958 patents, which cover the extended-released formulation of venlafaxine hydrochloride, the active ingredient in Effexor.

The basic patents expire March 20, 2017, while the '171 patent has pediatric exclusivity through Sept. 20 of that year.

Wyeth had filed a patent infringement lawsuit to block a generic version of the antidepressant drug made by Impax Laboratories last year. The case is still pending.

Sales of Effexor, the world's best-selling antidepressant, topped $3.7 billion for 2006, an increase of 8 percent over the previous year, according to figures released by Wyeth in January.