Bristol-Myers Squibb and AstraZeneca have filed their new type 2 diabetes compound saxagliptin, which they hope will be able to provide some competition to Merck & Co’s big-selling dipeptidyl peptidase-4 (DPP-4) inhibitor Januvia, in both the USA and Europe.

The companies said that marketing applications to the USFood and Drug Administration and the European Medicines for saxagliptin, which will have the trade name Onglyza. The submissions are based on studies that evaluated the drug “at up to 80 times therapeutic clinical doses”, B-MS and AstraZeneca said.

The six core Phase III trials for the submissions involved more than 4,000 patients, including 3,000 who were treated with saxagliptin. Those studies include Onglyza in combination with metformin, as well as its use as monotherapy in treatment-naive diabetics. Additional Phase III data for saxagliptin, including when added to a sulfonylurea and a thiazolidinedione are scheduled to be published later this year.

Some analysts have said that if approved, Onglyza could be a $2 billion drug but that pathway to approval may be about to become more complicated. At the beginning of the month, a panel of experts advised the FDA to insist that studies on new diabetes drugs need to include much more data on the potential heart risks of the treatments.

This could mean that it will no longer be enough to show that the drug merely lowers blood glucose levels and this in turn means more studies, increased costs and probable approval delays. B-MS and AstraZeneca are hoping to get approvals for saxagliptin in 2009 but if the process takes longer than that, Merck will continue to smile all the way to the bank.

There is still much excitement surrounding DPP-4 inhibitors, a new class of oral drug that enhances the body's own ability to lower blood sugar when it is elevated. However in the USA, there is only one DPP-4 inhibitor that has been approved, Merck ‘s Januvia (sitagliptin), and it could prove very difficult for other such treatments – eg saxagliptin and Takeda’s alogliptin – to make any major dent in its dominant position in the market.