Long-Acting Byetta Faces Approval ObstaclesNov 5, 2008 | Parker Waichman LLP A new version of Byetta, a diabetes drug made by Amylin Pharmaceuticals Inc. and Eli Lilly & Co., isn't going to be approved by the Food & Drug Administration (FDA) anytime soon. Amylin said yesterday in a regulatory filing that data for the new Byetta didn't satisfy the FDA's standards.
The original Byetta was approved by the FDA in 2005 to help type 2 diabetics better control blood sugar when other drugs were not adequate. The twice-daily injection is a synthetic form of a lizard hormone that boosts the production of insulin. Insulin is vital to controlling blood sugar levels. The new version of Byetta would be taken once-weekly.
According to Amylin's filing with the Securities and Exchange Commission (SEC),the FDA rejected data from studies meant to show that new Byetta batches made by partner Alkermes were equivalent to batches made at Amylin's Ohio facility. If Amylin has to conduct an additional study, it would likely delay its plans to ask for approval by the middle of 2009. Amylin said it is continuing discussions with the FDA.
The probable approval delay is just the latest troubling news surrounding Byetta. On August 18, the FDA said that Byetta had been linked to 6 cases of hemorrhagic or necrotizing pancreatitis in patients taking Byetta since its October alert. All patients required hospitalization, two patients died and four patients were recovering at time of reporting. Byetta was discontinued in all 6 cases. Then, on August 26, Amylin announced that four additional fatalities had been confirmed in Byetta patients suffering from milder forms of pancreatitis.
Just last October, the FDA said that 30 people developed pancreatitis that was associated with the use of Byetta. Of those, 5 later suffered from kidney failure. Six patients experienced the onset or worsening of symptoms after their dosage of Byetta was increased from 5 milligrams twice daily to 10 milligrams twice daily. And according to the FDA, pancreatitis symptoms in 22 patients subsided or improved once they quit taking Byetta.
Those safety problems could also ultimately impact the approval prospects for the new version of Byetta. Because of its long-acting nature, once-weekly Byetta cannot be quickly removed from the body, which would be a problem for a patient who developed pancreatitis. In most instances where Byetta patients develop pancreatitis, the problem subsides once treatment is halted. That would not likely be the case with the long-acting version.