Eli Lilly has acquired Alnara Pharmaceuticals, a developer of drugs for metabolic diseases, for an undisclosed amount, giving the global company a foothold in a new therapeutic area that may help it replace pending revenue losses. Like all major pharmaceutical companies, Lilly stands to lose millions as its patents protecting its top-selling medicines expire during the next decade. The Alnara deal gives it “a promising entry into enzyme replacement therapy,” says Bryce Carmine, EVP and president of Lilly BioMedicines.

By buying Alnara, Lilly gains ownership of its lead late-stage protein therapeutic, liprotamase, which is already under review by the U.S. Food and Drug Administration. The medicine, a non-porcine pancreatic enzyme replacement therapy for cystic fibrosis patients, is being considered as a treatment of exocrine pancreatic insufficiency.

If approved, liprotamase will allow many patients to take significantly fewer pills than they now take with current treatment options.

Lilly's CEO, John Lechleiter, told The Wall Street Journal that he doesn't expect to pursue any large mergers. “We've seen no evidence that the large combined companies are going to be any more innovative than Eli Lilly currently spending between $4 [billion] and $5 billion a year on research and development," he said in a WSJ interview.

The area of enzyme replacement therapy, which generally caters to niche patient populations, has proven lucrative for companies such as Genzyme and Shire, which have developed or marketed enzyme replacement therapies for Gaucher's Disease. GlaxoSmithKline and Pfizer have also recently entered the market, by way of deals with Japan's JCR Pharmaceuticals and Israel's Protalix Biotherapeutics, respectively.

Alnara, which is based in Cambridge, Massachusetts, has suggested the market for liprotamase might be worth $400 million alone, a prospect which attracted venture funding to the young company from MPM Capital, Third Rock Ventures, Frazier Healthcare and Bessemer Venture Partners before Indianapolis-based Lilly snapped it up.

The transaction is contingent on Hart-Scott-Rodino clearance and other customary closing conditions, Lilly said.