Deaths now associated with diabetes drug Byetta. Source: New York Times

Amylin Pharmaceuticals and Eli Lilly have provided context regarding the recent FDA warning for Byetta, revealing that four new deaths occurred in patients with pancreatitis, who were taking the injectable diabetes drug.

The companies said they were aware of the pancreatitis cases referenced in the warning, as well as others, and previously reported the cases to the FDA. 

James Malone, Lilly's chief medical officer, said that the FDA was aware of the four additional deaths, but said the agency chose not to announce them because it was "concentrating on the more severe forms of the condition." However, Malone also noted that "we felt it was important to get this information out there" and specified that the four cases involved patients who also had other medical conditions, which were likely the primary cause of death.

No definite relationship between Byetta and the additional deaths has been proved, and the FDA was aware of them when it made its announcement last week, Amylin’s CEO Dan Bradbury, told Bloomberg.

Since 2006, the Lilly and Amylin said that U.S. prescribing information for Byetta (exenatide) has included information about pancreatitis. A study, presented last week at the 24th International Conference on Pharmacoepidemiology and Therapeutic Risk Management 2008 in Copenhagen, Denmark, found that patients with type 2 diabetes were at nearly three times the risk of developing pancreatitis than those without diabetes.

The drugmakers said that while “a definite causal relationship between exenatide and pancreatitis has not been proved, to better understand the suspected relationship, Amylin and Lilly continue to pursue a comprehensive drug safety program that includes extensive internal and external review of individual cases, and clinical and epidemiologic studies.”

Malone added that similar issues have been noted with other treatments, indicating that “with all other diabetes medications we know there has been pancreatitis and some of those people have died. So it's not a unique phenomenon with Byetta.”

Diabetes patients have a threefold risk of pancreatitis, or inflamed pancreas, and as many as 20 percent of patients with the condition develop complications, Bradbury told Bloomberg.