The FDA has announced that starting in early April, its Endocrinologic and Metabolic Drugs Advisory Committee will begin looking into two new drugs for type 2 diabetes: saxagliptin tablets from Bristol-Meyers Squibb and liraglutide, an injection drug from Novo Nordisk.

Both drugs are designed to lower blood glucose levels in people with type 2 diabetes, but there are concerns that they may be linked to a higher occurrence of cardiovascular problems in diabetes patients. Consequently, the committee will focus on whether either treatment increases patients' risk of heart attacks or strokes.

Neither drug is a totally new therapy. Saxagliptin is similar to Merck's Januvia, a DPP-4 inhibitor that works by increasing the body's level of incretin hormones, which lowers blood glucose.

Liraglutide, like Amylin Pharmaceuticals' and Eli Lilly & Co.'s Byetta, is a long-acting form of the hormone GLP-1, which triggers the release of insulin. Unlike Byetta, which is injected twice daily, liraglutide will be marketed as a once-daily injection.

(Amylin and Lilly currently are testing a long-term form of Byetta that would be injected once a week. Timed-release capsules in the injection dissolve at specific intervals to deliver a continuous supply of the drug to the patient.)

The FDA's desire to scrutinize saxagliptin and liraglutide comes from its December 2008 directive calling for all new diabetes drug treatments to demonstrate that they do not increase cardiovascular risks.

Among the new testing conditions requested by the agency is the inclusion of older, sicker diabetes patients who are at higher risk of having a heart attack or stroke. Additionally, it is asking that drug studies follow patients for up to two years, versus the current three to six months.

Because both drugs were submitted to the FDA before issuance of the new December guidelines, there is some question about whether the agency will request more clinical data from the manufacturers.