The Food and Drug Administration on Monday announced that it’s seeking a stronger, more prominent warning about Byetta. The announcement follows six new reports of patients developing a dangerous form of pancreatitis while taking the drug. Two of the patients died and four were recovering.

Byetta, manufactured by Eli Lilly & Co. and Amylin Pharmaceuticals Inc., is available in the US since June 2005 for the treatment of type 2 diabetes.

The reports received by the FDA follows an earlier warning last October, when the agency cited 30 reports of pancreatitis in Byetta patients. None of those patients had hemorrhagic or necrotizing pancreatitis. However, the FDA then asked Amylin to include a warning on acute pancreatitis in the “precautions” section of Byetta’s label. Now the agency wants to strengthen that warning, but it was not immediately clear whether the FDA would order a “black-box” warning, the strongest type available.

Pancreatitis is the inflammation of the pancreas that can cause bleeding. The condition can also lead to toxins being released into the bloodstream that will negatively affect other organs in the body, leading to death in some cases.

Pancreatitis is rare in the general public but more common among type 2 diabetes patients, the manufacturers of Bietta said. Moreover, there have been rare reports of pancreatitis in Byetta patients and very rare reports of pancreatitis with complications or fatalities. The number of these cases is “similar” to that observed in the general public with pancreatitis, the companies added. However, they said that would work with the FDA to update the drug’s label.

Following the FDA announcement, Amylin’s shares closed down 13 percent at $29.76 on the Nasdaq, while Eli Lilly’s shares were down 1.5 percent at $48.05 on the New York Stock Exchange.