NEW YORK (AP) -- Alkermes PLC and Elan Corp. said Friday that Alkermes completed its acquisition of Elan's drug technology business. As part of the deal, Irish drug maker Elan received $500 million in cash and 31.9 million shares of Alkermes, giving it a 25-percent stake in the company. Alkermes also reincorporated in Ireland as part of the deal. It is now headquartered in Dublin after being based in Waltham, Mass. It valued the deal at $1 billion. The companies agreed to the deal in May. The deal is expected to double Alkermes' annual revenue and make the company profitable, allowing it to make bigger investments in research. The company will also pay lower taxes. Elan said it expected to save $130 million a year in payments on debt. Elan said Friday that it will use part of the proceeds to buy back up to $721.2 million in senior notes due in 2013 and 2016. Shares of Alkermes lost a penny to $16.51 in afternoon trading, while Elan shares fell 9 cents to $9.71.