U.S. health regulators are seeking stronger warnings about the risk of pancreatitis after the deaths of two patients taking Amylin Pharmaceuticals' injectable diabetes drug Byetta, sending the company's shares down as much 16 percent.
The Food and Drug Administration Monday said it had received six reports of hemorrhagic or necrotizing pancreatitis requiring hospitalization. Two of the patients died and the four others were recovering at the time of the reports.
The FDA said it was working with Amylin "to add stronger, more prominent warnings in the product label." Amylin co-markets the drug—one of the most successful new diabetes medicines in recent years—with Eli Lilly.
Amylin's shares were down about 15 percent at $28.95 in afternoon trading on the Nasdaq, while Eli Lilly's shares fell 1.7 percent to $47.92 on the New York Stock Exchange.
Pancreatitis is an inflammation of the pancreas, which helps aid in digestion by releasing vital hormones. The condition usually subsides quickly, according to the Merck Manual of Medical Information.
Complications or death are rare, Amylin and Lilly said in a statement. Rates of such problems are about as common in patients taking the drug as in others who have pancreatitis.
In October, the FDA said it had reviewed 30 reports of pancreatitis in patients being treated with Byetta. At the time, Amylin agreed to add information about the risk on its drug label and to alert doctors about the problem.
It was not immediately clear if the FDA would order new so-called "black box'' warnings, the strongest type available, and representatives for the agency could not immediately be reached.
The companies said they would work with the agency to update the drug's label.