Against a backdrop of flattening sales of its only marketed diabetes drugs and a new class of oral drugs - SGLT2s - entering the market from competitors, Merck & Co. Inc. appears to be shoring up its position.

Last Monday, Merck and Pfizer Inc. announced they will co-develop and co-commercialize Pfizer's ertugliflozin, plus fixed-dose combinations of the oral sodium-glucose cotransporter 2 (SGLT2) inhibitor with metformin and with Merck's Januvia sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor.