Merck sues India's Glenmark for stomping on Januvia patent

Merck ($MRK) is the latest Big Pharma to join India's pharma-patent fray. Generics maker Glenmark Pharmaceuticals hit Merck with premature generic versions of its diabetes blockbusters Januvia and Janumet. Now, the U.S.-based company has fired back with a lawsuit in Indian court.

Merck's Indian unit, MSD Pharma, holds a domestic patent on the active ingredient in Januvia, which is combined with metformin in Janumet. Still, Glenmark launched its versions of the drugs last week, just as India's Supreme Court was preparing its verdict against Novartis ($NVS)  in a landmark patent case.

"Glenmark is a responsible company and has launched the products after due diligence and research," the Indian company told Reuters.

Glenmark officials told India's Economic Times that their versions--dubbed Zita and Zita Met--would sell at a 20% discount to MSD's price of about 1,200 rupees per month, or $22. The two drugs are among the top-selling diabetes treatments in India, with 2011 sales of about 3 billion rupees, or $55 million, the ET says.

MSD told the ET that it believes its patents on the two drugs are "valid and enforceable," and that it would "vigorously" defend them. "We are disappointed with Glenmark's decision to directly infringe upon our intellectual property," an MSD spokesperson told the ET.

Glenmark isn't the only domestic company to launch copies of Big Pharma's on-patent drugs. Cipla began selling its version of Bayer's Nexavar long before the Indian government granted Natco Pharma a compulsory license. The company has also been selling a version of Roche's ($RHHBY) Tarceva and recently cut its already-discounted price on that product by another 63%.

But like its multinational competitors, Merck has targeted India and other emerging markets for growth. And when CEO Kenneth Frazier took over in 2010, he talked up plans for tiered pricing, to make its products more affordable to patients in developing countries.

- read the Reuters news
- get more from the ET

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