HAYWARD, Calif., Aug. 7, 2017 /PRNewswire/ -- Impax Laboratories, Inc. (NASDAQ: IPXL ), today announced a Settlement Agreement (the "Contract Settlement Agreement") to resolve a contract dispute relating to an agreement entered into in June 2010 among Endo International plc ("Endo"), Penwest Pharmaceuticals and Impax regarding the Abbreviated New Drug Application litigation related to the original formulation of Opana ® ER (oxymorphone hydrochloride) CII Extended-Release ("ER") tablets (the "2010 ANDA Settlement"). In the 2010 ANDA Settlement, Impax obtained a non-exclusive license to certain then-existing and future Endo patents. Orange Book listed patents for Opana ER extend until November 2029.