Merck & Co, Inc announced that the US District Court for the District of New Jersey has ruled in Merck's favour in a patent infringement suit against Teva Pharmaceuticals USA Inc. (Teva). Teva was seeking FDA approval to sell a generic version of 4, 5 and 10 mg tablets of Singulair (montelukast sodium), Merck's asthma and allergic rhinitis medicine.

In his decision, Judge Garrett E Brown upheld Merck's patent on Singulair and ruled that Teva committed infringement. Judge Brown also issued an injunction blocking the approval of Teva's generic versions until the August 2012 expiration of the patent.

"The court appropriately ruled that the patent for Singulair in the US is valid," said Bruce Kuhlik, executive vice president and general counsel of Merck. "We invest heavily in the R&D that is needed to discover innovative medicines like Singulair, and we will vigorously defend our intellectual property rights."

Merck filed the patent infringement lawsuit against Teva in February 2007. The trial was heard before Judge Brown in February 2009.