Generic drug companies win fight to make Pronova's Lovaza

WASHINGTON, Sept 12 (Reuters) - Generic drug companies can develop generic versions of Lovaza, a fish-oil derived drug used to treat high cholesterol, a U.S. appeals court ruled on Thursday.

In April 2009, Pronova BioPharma Norge AS filed a patent infringement lawsuit in Delaware against Teva Pharmaceuticals USA Inc and Par Pharmaceutical Inc, to prevent them from bringing out a generic version of Lovaza.

The drug is marketed in the United States by GlaxoSmithKline (LSE: GSK.L - news) Plc. Glaxo's U.S. sales of the drug were $916 million in 2011. German chemicals firm BASF bought Pronova this year.

A judge in Delaware agreed that Pronova's two patents for the drug were valid and would be infringed by a generic product.

But the U.S. Court of Appeals for the Federal Circuit disagreed with the lower court, ruling that one of that patents was invalid. Since the other expired in March, the appeals court reversed the lower court's decision.

However, the decision can be appealed to the U.S. Supreme Court.