INS and diabetes mellitus: In clinical trials such as the U.K. Prospective Diabetes Study (UKPDS) and Diabetes Outcome Progression Trial (ADOPT), the findings showed that sulfonylureas initially increase early-phase insulin secretion in response to oral glucose tolerance tests, thus leading to a more rapid rate of deterioration of beta cell function and overall glycemic control compared to treatment with metformin, thiazolidinediones or insulin therapy (10, 11).