Endo, Impax to Face Class Action Trial in Opana Antitrust Case

Endo International Plc and Amneal Pharmaceuticals Inc. unit Impax Laboratories lost their bid Friday to head off a trial in a Chicago federal court of class action antitrust claims over a patent settlement that allegedly delayed generic versions of Endo’s prescription pain reliever Opana ER.

Judge Harry D. Leinenweber issued a pair of companion rulings in the U.S. District Court for the Northern District of Illinois, formally certifying the consolidated case as a class action and denying a summary judgment bid by the pharmaceutical companies.

Although the drugmakers have plausible defenses—such as their claim that the settlement ending Endo’s earlier ...