NEW YORK (AP) — Sepracor Inc. said Tuesday it will allow Teva Pharmaceutical Industries Ltd. to launch generic versions of its respiratory drug Xopenex in 2013 under terms of a patent lawsuit settlement. Teva will be able to launch a licensed generic version of Xopenex inhalation solution on Feb. 17, 2013, and the company will pay Sepracor a royalty on sales. Sepracor had sued Barr Pharmaceuticals, now a unit of Teva, to prevent the company from selling its own generic version. Sepracor and Teva will ask the U.S. District Court for the District of Delaware to dismiss their litigation. In 2008, Sepracor reported $441 million in Xopenex revenue. The drug is intended to treat shortness of breath for patients with asthma or chronic obstructive pulmonary disease. The Marlborough, Mass., company reached a similar settlement with Breath Ltd., a unit of Arrow Group, in May 2008. Under that settlement, Breath will be able to start selling its generics in August 2012. A patent lawsuit against Mylan Inc.'s Dey LP subsidiary is continuing. The patents supporting Xopenex, or levalbuterol, begin to expire in March 2013.