Tom Lamb and the Drug Injury Watch have a good article on the selective information given by Amylin Pharmaceuticals about their diabetes drug Byetta (co-marketed with Eli Lilly) to the media and their investors in October, 2009. Apparently, they released the good information that the FDA approved it as a stand-alone medication for adults with type 2 diabetes. The only caveat was that the labeling would have to warn about the risk of pancreatitis in patients with severe kidney disease.
At the end of December, however, when the FDA letter to Amylin was obtained, a more complete picture emerged. It seems that the FDA also required human and animal studies to further investigate the risk of pancreatitis “to ensure that the benefits of the drug outweigh the risks of acute pancreatitis and acute renal failure.” These additional studies are necessary because “an analysis of spontaneous postmarketing adverse events reported . . . will not be sufficient to assess the signal of a serious risk of acute pancreatitis, including hemorrhagic or necrotizing pancreatitis, and the signal of a serious risk of thyroid neoplasms.”
See also the Bloomberg article on the selective information given by Amylin, which goes into more detail about the effects on Amylin’s stock prices.