Last Updated: 2007-03-21 12:00:23 -0400 (Reuters Health)

NEW YORK (Reuters) - Pfizer Inc. said on Tuesday a U.S. court upheld the three main patents covering its Celebrex arthritis treatment, winning a challenge by generic drugmaker Teva Pharmaceutical Industries Ltd.

The decision by the U.S. District Court in Newark, New Jersey bars Israel-based Teva from launching a competitor drug in the U.S. until December 2015, Pfizer said.

Pfizer had filed suit against Teva in February 2004 after the generic drugmaker asked U.S. regulators for permission to sell a copycat version of Celebrex.

Celebrex, which was approved in 1998 and had sales last year of $1.57 billion, is in the same class of medicines as Merck & Co's withdrawn Vioxx pain and arthritis treatment.

The pill works by blocking a protein called COX-2 that is linked to inflammation. Although designed to treat pain with a smaller risk of gastrointestinal problems than far less-expensive conventional painkillers, Celebrex has not proven such a safety advantage in clinical trials.