U.S.-listed Alkermes Inc. /quotes/zigman/67810/quotes/nls/alks ALKS +0.85% expects its acquisition of Elan Corp. PLC’s /quotes/zigman/170510/quotes/nls/eln ELN +1.01% drug-technology unit to propel the combined group to the ranks of Big Biotech, operating in central nervous system diseases with a portfolio of 25 products, five of which could be major money spinners well into the 2020s. “We’ll be driving that transformation with five key products that have very long patent lives and which are really critical products in their category,” Chief Executive Richard Pops told Dow Jones Newswires in an interview.