Indian pharmaceutical company Dr Reddy's Laboratories Ltd on Thursday said it has launched a generic version of Protonix, a drug used to control the amount of acid in the stomach, in the United States.

In a statement, Dr Reddy's said it has launched generic pantoprazole sodium delayed-release tablets in 20- and 40-milligram strengths.

The company said its tablets had total U.S. sales of about $1.8 billion for the 12 months to Sept. 30, 2010.

Earlier this month, World's largest drug maker Pfizer had moved the court against Dr Reddy's Laboratories seeking a delay in launching the Indian drug maker's low-cost version of atorvastatin, the world's best-selling medicine, in the US market.

Pfizer had said in its filing before a American local court in Delaware last Monday that Dr Reddy's plan to launch a generic version of atorvastatin sold under the Lipitor brand will infringe upon its patent.

The drug maker, which rakes in over $12 billion in global sales from Lipitor, has asked the court to withhold approval of the drug until one of its patents for Lipitor expires in January 2017.