Much-Anticipated Byetta Cousin Rejected Again by the FDA

Washington, D.C.The makers of Byetta have been dealt a serious blow by the US Food and Drug Administration (FDA) after the regulatory agency rejected the much-anticipated, once-weekly Bydureon injection. This is the second time Bydureon, to be manufactured by Amylin, Eli Lilly and Alkermes, has been given the thumbs-down. The response letter from the FDA, according to a recent report in The New York Times, cited the need for a study to test for cardiac effects—something the manufacturers say could take two years.

Byetta is an injectable diabetes drug that has been linked in the past to Byetta acute pancreatitis, among other adverse reactions. The makers of Byetta have been under pressure to develop an improvement on Byetta for two reasons: they face increased competition from generic drugs soon entering the market, and the need to inject Byetta twice daily proves distasteful for many.

A Byetta competitor, Victoza and manufactured by Novo Nordisk, requires injection only once per day. In contrast, Bydureon requires injection only once per week.

The FDA rejection this time took most by surprise, although industry watchers note that the FDA has been more diligent recently with regard to testing for possible adverse cardiovascular effects.

Among existing Byetta side effects is impaired kidney function and the potential for renal failure—in addition to the potential for acute pancreatitis. Given the similarity of formulations between Byetta and Bydureon [the biggest difference that allows for a once-weekly injection comes from technology provided by Alkermes], the FDA's hesitation could be understandable.

In its coverage of the FDA rejection of Bydureon on October 20th, The New York Times reported that the federal drug watchdog is concerned that patients with kidney impairment may not succeed in clearing Bydureon effectively from their bodies, allowing for the buildup of Bydureon concentrations in the bloodstream.

According to an Amylin spokesperson, previous studies on animals as well as humans had not revealed any problems with the "QT interval," a measure employed to predict potential disruptions in heart rhythm that could lead to death. However, the FDA is concerned that concentrations due to the long-lasting nature of Bydureon could be higher than with Byetta.

The FDA first rejected Bydureon in March. This latest piece of Byetta news is said to have even caught investors by surprise. Most thought Bydureon would be approved this time.

The two-year delay required to accomplish the cardiovascular study will result in the loss of further market share to Novo Nordisk, while a host of plaintiffs afflicted with Byetta acute pancreatitis and other adverse reactions pursue compensation through the services of a Byetta attorney.