FDA approves Ironwood’s irritable bowel drug
Ironwood Pharmaceuticals Inc. says it is on track to start selling a treatment for chronic constipation and irritable bowel syndrome, following approval of the drug by federal regulators Thursday. The highly-anticipated pill, called Linzess, will be the first product developed by the 14-year-old Cambridge company to hit the market. FDA approval was expected, but most observers had predicted it would come next month. Analysts say Linzess could be a blockbuster, capable of pulling in $1 billion in annual worldwide sales within a decade.