Placebo to Sitagliptin

Study to Assess Safety & Efficacy of Sitagliptin as Initial Oral Therapy for Treatment of Type 2 Diabetes Mellitus in Pediatric Participants. (MK-0431-083)

Omarigliptin (MK-3102) Clinical Trial - Placebo- and Sitagliptin-Controlled Monotherapy Study in Japanese Patients With Type 2 Diabetes Mellitus (MK-3102-020)

Randomized Sitagliptin Withdrawal Study (MK-0431-845)

Study Of Safety And Efficacy Of Ertugliflozin (PF-04971729, MK-8835) In Participants With Type 2 Diabetes (MK-8835-016)

Efficacy and Safety of Ertugliflozin (MK-8835/PF-04971729) With Sitagliptin in the Treatment of Participants With Type 2 Diabetes Mellitus (T2DM) With Inadequate Glycemic Control on Diet and Exercise (MK-8835-017)

Study to Evaluate the Safety and Efficacy of the Addition of Omarigliptin (MK-3102) Compared With the Addition of Sitagliptin in Participants With Type 2 Diabetes Mellitus With Inadequate Glycemic Control on Metformin (MK-3102-026)

A Study of the Efficacy and Safety of MK-0431D (a Fixed-dose Combination of Sitagliptin and Simvastatin) for the Treatment of Participants With Type 2 Diabetes Mellitus (T2DM) With Inadequate Glycemic Control on Metformin Monotherapy (MK-0431D-266)

A Study of the Co-administration of Sitagliptin and Atorvastatin in Inadequately Controlled Type 2 Diabetes Mellitus (MK-0431E-211)

Safety and Efficacy of Sitagliptin Compared With Glimepiride in Elderly Participants With Type 2 Diabetes Mellitus (MK-0431-251)

A Study of Different Doses of Sitagliptin (MK-0431) in Participants With Type 2 Diabetes Mellitus (MK-0431-014)

An Investigational Drug in Patients With Type 2 Diabetes Mellitus and Chronic Renal Insufficiency (0431-028)(COMPLETED)