Amylin Pharmaceuticals Takes Over Byetta

Dallas, TXAmylin Pharmaceuticals has taken full control of Byetta marketing in the US and will take full control globally in 2013, according to reports. Eli Lilly formerly partnered with Amylin to market Byetta (known generically as exenatide). Byetta side effects reportedly include an increased risk of acute pancreatitis.

Among the deal that sees Amylin taking full control of Byetta is concern about Bydureon, which is a once-weekly injectable version of Byetta. Bydureon has not yet been approved by the FDA. According to Medical Marketing & Media (12/01/11), Amylin will pay Lilly $250 million upfront for control of Byetta, plus royalties of up to $1.2 billion on future sales.

Byetta is used in patients with diabetes. When it was initially approved for use on the market, in 2005, it was approved only in combination with other anti-diabetic medications. Since that time, however, it has been approved for use by itself. The US Food and Drug Administration (FDA) has updated the label for Byetta multiple times to include the reported risks of acute pancreatitis, hemorrhagic pancreatitis and altered kidney function.

In 2009, the FDA issued a warning that Byetta was potentially linked to an increased risk of kidney problems. When it made the announcement (11/02/09), the FDA noted that from April 2005 through October 2008, the agency received 78 reports of altered kidney function in patients using Byetta. Among the reports of altered kidney function were 62 cases of acute renal failure and 16 cases of renal insufficiency. The FDA also noted that of the 6.6 million prescriptions filled for Byetta in the included time frame, 78 reports of adverse reaction represented a small percentage.

The FDA reported that cases of acute renal failure occurred in patients ranging in age from 23 to 83 years and happened between three days and two years of initiating Byetta therapy. Most of the patients who experienced altered kidney function had at least one contributory risk factor, including cardiac insufficiency, hypertension and pancreatitis. Furthermore, more than half the patients had symptoms such as diarrhea and/or vomiting, which are also risk factors for kidney problems.

Of the 78 reports of altered kidney function, four patients died and 71 patients required hospitalization. Eighteen patients required dialysis and two underwent a kidney transplant. In 63 of the 78 reports, patients discontinued Byetta, and of those, 39 reported a lessening of symptoms of kidney problems once Byetta was discontinued.