The lawsuit was filed in the United States District Court of New Jersey last week, sources said. The suit follows a marketing application filed by the company with the US Food and Drug Administration (FDA), the drug regulator in the US, for launching a generic version of the patented drug. As per the US rules, an innovator company has to sue the generic challenger within 45 days, to freeze any decision by the regulator to allow the application.
"Dr Reddy's is unlikely to gain much upside from this drug, even if the company is able to get a favourable verdict. Mylan Laboratories of the US has 180-day exclusivity for selling the drug in the US for 500 mg-strength from January 1, 2009, as per an out-of-court settlement and has a licence to sell 250 mg tablets," said Varun Chonker, a patent expert.
Abbott had also sued Indian drug makers Wockhardt, Impax Laboratories and Israel-based Teva Pharmaceuticals for challenging the patent on this drug in the last three years.
A spokesperson of Dr Reddy's said he would require more time to respond on the development, as the information on this issue has to come from the US office of the company.
Currently, Dr Reddy's is also engaged in patent litigations over Roche's Boniva, which is used to treat or prevent osteoporosis in women after menopause, allergy drugs Clarinex-D of Schering-Plough Corporation and Allegra of sanofi-aventis and respiratory drug Avelox of Bayer.
Dr Reddy's is believed to have filed the first marketing application for generic versions for these drugs. This will qualify the company to secure 180-day exclusive marketing right of the drug on patent expiry.
