Impax faces generic Oxycontin patent challenge

HAYWARD, Calif. — Another generic drug maker is seeking to market its version of a popular opioid painkiller.

Impax said it had filed applications with the Food and Drug Administration seeking approval for a generic version of Purdue Pharma’s Oxycontin (oxycodone) controlled-release tablets in the 10-, 15-, 20-, 30-, 40-, 60- and 80-mg strengths.

Purdue filed suit against Impax on April 8 in the U.S. District Courts for the Southern District of New York, seeking to prevent Impax from marketing its version before the expiration of Purdue's patents.

According to Wolters Kluwer Health, aggregate U.S. sales of Oxycontin since launch were approximately $2.8 billion for the 12 months ended in January.