Here’s Why Pfizer’s Holding on to Its Celebrex Patent With Both Hands
Patent expirations continue to be a problem for the United States’ largest pharmaceutical manufacturers. Since Pfizer’s (NYSE:PFE) patent for its blockbuster cholesterol medicine Lipitor — which for nearly a decade was the world’s top selling drug — expired in 2011, earnings and revenue have struggled to grow. Like many large drug manufacturers, cheaper generic versions of its once top selling pharmaceuticals are eroding sales for drugs, no longer protected by patents that once earned Pfizer billions annually. It is for that reason that the company is pursuing a so-called method of use patent for its arthritis pill Celebrex. The drug belongs to a class of drugs called COX-2 that helps lower pain for arthritis patients by blocking a chemical reaction in the body that causes inflammation.
A method of use patent covers the use of a product to treat certain health problems or diseases, and Pfizer argued in the United States District Court for the Eastern District of Virginia that the company should be able to retain marketing exclusivity and an additional 18 months of a market monopoly because the reissued patent covers methods of treating osteoarthritis and other approved conditions with celecoxib, the active ingredient in Celebrex. The reissued patent was intended to extend market exclusivity for the drug to December 2, 2015 from May 20, 2014, when the original patent covering the basic chemical compound in Celebrex is due to expire. The issue reached the courts after Pfizer sued generic companies — Teva Pharmaceuticals (NYSE:TEVA), Mylan Pharmaceuticals, Watson Laboratories, Lupin Pharmaceuticals, and Apotex — for infringement of the reissued patent. Those competitors filed abbreviated new drug applications with the U.S. Food and Drug Administration for approval to market a generic form of celecoxib in the United States beginning on May 30, 2014.
However, the generic drug makers successfully argued that the patent Pfizer accused them of infringing upon was not significantly different from the one nearing expiration, and the Virginia District Court ruled that the reissued patent was invalid. Pfizer has already indicated it will appeal the summary judgement, confirming Wednesday in a press release that the company “disagrees with the ruling and will pursue all available remedies” to overturn it. But for now, Celebrex is set to face tough generic competition beginning at the end of May.