Glucagon and insulin work in concert to achieve and maintain proper blood glucose levels. Glucagon, released by pancreatic alpha cells, prevents hypoglycemia, while insulin released by beta cells prevents hyperglycemia. Together they preserve a tight blood glucose concentration between 70-100 mg/dL fasting and 70-140 mg/dL after meals. In type 2 diabetes, glucagon production, release, and action are malfunctioning. Overproduction of glucagon leads to over-stimulation of gluconeogenesis and glycolysis, in turn exacerbating hyperglycemia of diabetes mellitus.
It is only natural to look for ways of lowering the synthesis, secretion, or effects of glucagon. In this phase-2 clinical trial, the researchers tested the ability of a glucagon receptor antagonist in lowering A1c in 166 patients with metformin-uncontrolled type 2 diabetes over 12 weeks. The glucagon receptor antagonist RVT-1502, at the high dose 15 mg per day, lowered A1c by 1.0% without severe hypoglycemia. Slight and mild elevation of aminotransferases and blood pressure were documented respectively.
Since study results are meaningfully positive, a follow-up phase-3 randomized clinical trial would be expected.