Amylin shares fall ahead of diabetes drug decision

NEW YORK

Shares of Amylin Pharmaceuticals Inc. fell nearly 4 percent Thursday ahead of a potential Food and Drug Administration decision on the company's long-acting version of a diabetes drug.

Stock in the San Diego company has been extremely volatile, and earlier in the day hit a 52-week high.

The FDA is expected to make a decision on Amylin's exanatide-LAR on Friday. The drug is a once-weekly version of the injectable treatment Byetta, which is currently taken twice daily.

"Amylin's stock price in particular could be quite volatile over the next weeks as there are an unlimited number of scenarios surrounding the outcome of the March 12th action date for Byetta (exenatide LAR)," said Credit Suisse analyst Catherine J. Arnold, in a note to investors.

She reaffirmed a "Outperform" rating on the stock, saying the FDA could choose to take more time reviewing the drug application, which would knock down shares.

The market for diabetes drugs will likely become even more cramped in the future. In January, the FDA approved Novo's Victoza, which is taken once-daily. That drug is part of the same GLP-1 class as Byetta, which works by increasing the body's insulin production.

Victoza was under review for two years, with safety concerns slowing down the process. It was approved with a warning over the risk for thyroid cancer and the company had to develop a risk-mitigation plan for patients.

There are several other diabetes treatments on the market from the DPP-4 class, which also works to regulate blood sugar levels. Merck & Co. makes the diabetes drug Januvia, while Bristol-Myers Squibb Co. and AstraZeneca make Onglyza. Another potential DPP-4 drug called alogliptin, is still being studied by Takeda Pharmaceutical Co. Ltd.

On Thursday afternoon, shares of Amylin Pharmaceuticals Inc. fell 76 cents to $20.14.