[THE INVESTOR] Daewoong Pharmaceutical plans to file a lawsuit against Korea United Pharmaceutical for patent infringement, according to industry sources on Aug. 12.

Daewoong claims that Korea United stole its patented sustained release technology that lets the drug maintain the efficacy for a longer time, in developing Gastiin CR tab, a new drug to improve indigestion.

Gasmotin, the original medicine containing Mosapride Citrate made by Japan’s Dainippon Sumitomo and imported by Daewoong, and its generic are to be taken three times a day while Gastiin CR only needs to be administered once a day.

As Gasmotin’s patent expired in 2011, Daewoong attempted to develop a modified version. Although the pharmaceutical company dropped the project, it has obtained several patents during the research and development, including the technology to prolong the impact of the drug.

Daewoong is taking legal action to defend the market of the original drug that has already shrunk to 19.8 billion won (US$17.97 million) in revenue last year from 40.8 billion won in 2011, the sources said.

Korea United claims that it “has developed its own technology without infringing that of Daewoong, which slowed down the development of its new drug,” released last month.

By Hwang You-mee (glamazon@heraldcorp.com)