Irish drug company Elan ( ELN) said it completed the sale of the European rights to Prialt, a treatment for severe chronic pain, to Japan's Eisai. Under the terms of the sale, Elan received roughly $50 million when the deal closed. The company will receive an additional $10 million either two years from now or when Prialt is rolled out in key European markets, whichever comes first. Elan could get $40 million more if Prialt reaches certain revenue-related milestones in Europe. Elan is retaining the product rights in the U.S. Elan's American depositary receipts edged up 3 cents to $14.85 in after-hours trading Monday. The ADRs slipped 19 cents in the regular session.