PARSIPPANY, N.J. — Generic drug maker Watson Pharmaceuticals is challenging the patent protection on an antidepressant made by Pfizer, the company said.
Watson filed a regulatory approval application with the Food and Drug Administration for desvenlafaxine succinate extended-release tablets in the 50-mg and 100-mg strengths. The drug is a generic version of Pfizer's Pristiq.
Watson's application included a paragraph IV certification, a legal assertion that patents covering the branded drug are invalid, unenforceable or won't be infringed, and the company said it was the first to file a complete application for a generic version of Pristiq. In response, Pfizer and others filed suit against Watson Friday in the U.S. District Court for the District of Delaware to try and prevent Watson from commercializing its product before the expiration of U.S. Patent No. 6,673,838, which is set to expire in 2022. The suit puts a stay of approval on Watson's drug until August 2015 or until the companies settle the case.
Pristiq had sales of about $559 million during the 12-month period ended in April, according to IMS Health.