Pfizer wins extension of Lipitor patent

WASHINGTON - Pfizer Inc. won new protection on the cholesterol pill Lipitor, the world's best-selling drug, after the United States agreed to reissue a patent on the drug's key ingredient that had been invalidated by an appeals court.

The US Patent and Trademark Office said it would reissue a patent that expires in June 2011 after Pfizer altered what an appeals court had called inconsistent language that made the patent invalid. Pfizer can get the patent if it pays a $1,510 fee, according to the agency.

The decision affirming Pfizer's patent rights to the compound bolsters its efforts to prevent Apotex Inc. and Teva Pharmaceutical Industries from selling a copy before November 2011, when India's Ranbaxy Laboratories Ltd. is scheduled to enter the US market. Sales of Lipitor were $3.1 billion in the third quarter.