FDA review accuses Amylin of withholding data on Bydureon app

TheStreet's Adam Feuerstein may have just thrown a wild card into the high-stakes bidding war for Amylin ($AMLN). 

With the company reportedly engaged in talks with a roster of potential buyers, including AstraZeneca ($AZN), Feuerstein laid his hands on a summary FDA review of the Bydureon app in which a senior FDA regulator complains that Amylin failed to tell the FDA of a significant safety study related to the diabetes drug and went on to delay the review process by dragging its feet on a QT study of the drug. The Financial Times followed TheStreet this morning with its own report, indicating that Amylin may have some explaining to do about its relationship with the FDA and the rest of its clinical trial work.

"The review and this eventual recommendation for approval of Bydureon has been a long and complicated process," writes the FDA's Mary Parks, "in part due to Amylin's withholding of information on Byetta that FDA deemed to be important to its evaluation of the safety and effectiveness of Bydureon."

At the heart of the controversy is a heart safety study that Amylin did measuring the electrical cycles of patients taking Byetta--called a QT study--which was done for Canadian regulators. Byetta, which has the same active ingredient as Bydureon and Amylin, sought and obtained the right to use its safety and efficacy data on Byetta to back up its NDA on Bydureon. Regulators were willing to consider an abbreviated clinical program for Bydureon, which would have been augmented with the data on Byetta. Instead, Amylin and its partner Eli Lilly ($LLY) were twice rebuffed by the FDA. And now the review indicates why the process took so long, fingering Amylin for stalling.

Amylin, according to the FDA, didn't make the heart safety study on Byetta – conducted outside the U.S.--available to the agency. It was only when Canada's drug agency alerted the FDA to the study that U.S. regulators found out about it. And even after the company was told to submit the data, says Parks, Amylin failed to provide the information in its resubmission for the treatment. 

The timing of the public review of the critical FDA report on Amylin's clinical program couldn't be worse. Bloomberg and Reuters have been regularly updating investors with insider accounts of the auction underway for Amylin, which also includes Takeda, Merck ($MRK), Sanofi ($SNY), Pfizer ($PFE) and Bristol-Myers Squibb ($BMY).

For its part, Amylin notes that Bydureon ultimately passed all the challenges it faced at the FDA and states that it is "committed to being transparent with regulatory agencies, the patients and physicians who put their trust in our products and our investor community. Our interactions with regulatory agencies have been, and will continue to be, forthright and timely."

- get the FDA review
- here's the story from TheStreet
- read the report from the Financial Times