Ranbaxy Laboratories shares surged 4.3 per cent on Thursday after its parent Daiichi Sankyo sent a statement to Japan's Stock Exchange (Nikkei) stating that it will start sales of a generic version of Lipitor in the US from November.
The anti-cholesterol blockbuster drug is expected to fetch nearly $500 million in revenues to Ranbaxy. The company's share price stood at Rs 507 at close on the Bombay Stock Exchange.
Lipitor, owned by Pfizer, is the world's largest selling drug and it loses patent protection in the US in November this year. Ranbaxy has 180 days of exclusivity on this product starting November 30 after it struck a deal with Pfizer in 2008.
Mylan case
However, doubts were raised on the company's exclusivity after US-based pharmaceutical company Mylan Inc sued the US Food and Drug Administration in March, seeking to block the Indian drug maker's rights.
Mylan, in a complaint filed on March 18 in a federal court in Washington, said it and other generic-drug makers should be allowed to enter the market as soon as Lipitor's patent expires later this year. It contended that Ranbaxy isn't eligible for marketing exclusivity because of false and unreliable data from its manufacturing site in Paonta Sahib, from where copies of Lipitor would be produced.
But in May, the US court dismissed the petition by Mylan Inc. The USFDA countered that Mylan lacked standing to file the lawsuit, the complaint was premature, and that the agency's enforcement discretion was not reviewable by a court.
Siding with the FDA, the US District Judge, Mr James Boasberg, ruled that drug makers cannot sue over pending applications filed by their competitors.
Lipitor had global sales of over $10 billion last year. In 2008, Ranbaxy had reached an agreement with Pfizer to sell generic version of the drug in the US market beginning November 30, 2011.
Ranbaxy had said it is entitled to 180 days of marketing exclusivity as a reward for agreeing to withdraw all litigation contesting the validity of Pfizer's patents in specified countries, including the US.