DPP4 and type 2 diabetes mellitus: Various selective DPP-IV inhibitors especially adamantane-based DPP-IV inhibitor have been developed and marketed as therapeutic agents for T2DM including vildagliptin in EU in 2007 (Galvus, Novartis)29, 30, and saxagliptin in the US in 2009 (Onglyza, BMS)31 are now used in many countries as monotherapies or in combination with other glucose-lowering agents.