Recently, U.S. District Court Judge Garrett Brown rejected the argument made by Teva Pharmaceuticals Industries Ltd. that the patent covering the main ingredient in Merck & Co.’s asthma and allergy treatment drug Singulair® was invalid or unenforceable. The patent that covers Singulair’s® main ingredient is U.S. Patent No. 5,565,473 and can be viewed at Google patents with this link: U.S. Patent No. 5,565,473.
Teva is the world’s largest generic drug maker and has a 22% market share of generic-drugs in the U.S. (Fortune Magazine – Teva: The King of Generic Drugs). The company has a history of persuading courts to invalidate pharmaceutical patents. For example, in 2004, Teva filed and won a lawsuit against Novartis International AG. In the lawsuit, the court found that Novartis’s patent for the blood pressure medicine Lotrel® was invalid.
A provision in the Hatch-Waxman Act, passed by Congress in 1984, gives generic drug companies an incentive to challenge pharmaceutical patents. According to the Hatch-Waxman Act, if a generic drug maker is able to prove that a patent protecting a drug is invalid, then the generic drug maker is given a six month window of sales exclusivity to sell their generic version of the drug.
Oddly enough, even though Teva is the world’s largest generic drug maker, the company does a significant amount of research on new drugs. In fact, the company developed and patented the active ingredient in the multiple sclerosis treatment Copaxone®, the patent for which expires in 2014.
Image from: http://tevausa.com/default.aspx?pageid=31