The US Food and Drug Administration (FDA) recently issued a complete response letter delaying the approval of Amylin Pharmaceuticals, Inc. (AMLN), Eli Lilly and Co. (LLY) and Alkermes, Inc.’s (ALKS) once weekly formulation of Byetta (exenatide). The companies are seeking to get Byetta once weekly (proposed trade name: Bydureon) approved for the treatment of type II diabetes.
Despite the delay, both Amylin and Alkermes shares were up significantly as the agency did not ask the companies to conduct additional clinical or pre-clinical studies. This is encouraging news as additional studies would have delayed approval significantly. 

We were concerned that safety issues surrounding the use of glucagon-like peptide-1 (GLP-1) molecules like exenatide could have led to the FDA asking for additional safety studies. However, we believe that the final label for Byetta once weekly is likely to contain warnings regarding the risk of pancreatitis and thyroid cancer. 

In its complete response letter, the agency has asked the companies to finalize the label and provide a Risk Evaluation and Mitigation Strategy (REMS) and clarification on existing manufacturing processes. 

The letter did not include requests related to the Dec 2009 observations from the FDA’s pre-approval inspection of the Ohio manufacturing facility. The companies stated that all the observations raised by the FDA at that time have been addressed. 

Amylin intends to respond immediately to the FDA’s requests. At present, there is little visibility as to whether this response will be treated as a class I or class II review. Depending on the classification, a decision from the FDA should be out 2-6 months after the response is submitted. 

Once launched, Amylin’s Byetta once weekly will face competition from Novo Nordisk’s (NVO) Victoza, a once-daily injection that received FDA approval recently. Other GLP-1 molecules under development include GlaxoSmithKline’s (GSK) Syncria (albiglutide) and Roche/Ipsen’s taspoglutide. We note that Glaxo’s Syncria, currently in a phase III program, is also a once-weekly injection. 

We currently have a Neutral recommendation on Amylin. While we were expecting a delay in Byetta once weekly’s approval, we are pleased to see that Amylin will not be required to conduct additional studies. Byetta once weekly should receive approval in the second half of 2010.
Read the full analyst report on “AMLN”
Read the full analyst report on “LLY”
Read the full analyst report on “ALKS”
Read the full analyst report on “NVO”
Read the full analyst report on “GSK”
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