Roche Holding AG sues generic drug maker Mylan Inc. for patent infringement in order to prevent it from selling a generic version of Roche’s Xeloda (capecitabine) breast cancer treatment. Mylan applied for FDA approval of the generic, but Roche wants a court to block approval until the patent on the medicine expires in 2013. Roche sued April 8 in federal court in Newark, New Jersey.