AstraZeneca plc emerged as Ironwood Pharmaceuticals Inc.'s preferred partner for linaclotide in China based on its willingness to support the biotech's rollout of the guanylate cyclase C (GCC; GUCY2C) agonist in the U.S. In a mutually beneficial move, Ironwood's U.S. sales reps will bolster their presence with GI doctors by simultaneously promoting the pharma's Nexium esomeprazole.

FDA approved linaclotide to treat irritable bowel syndrome with constipation (IBS-C) and chronic idiopathic constipation (CIC) in August. Ironwood will co-market the drug as Linzess in the U.S. with Forest Laboratories Inc.