<qa>  What is the first study visit for the participants?At the 2nd study visit Visit 2, which will take place 3 months after starting the combination drug, the participant will again come to the Diabetes Center after an overnight fast of at least 8 hours. The participant will undergo a second OGTT as in the first visit. The 3rd study visit Visit 3 will be 6 months after initiation of the drug, and will have a repeat administration of an OGTT. If a participant starts the combination drug before enrolling in the study, heshe can still participate in the study as long as he or she has had a clinical OGTT performed within 6 months of starting the combination drug. In these cases, the informed consent, brief medical history, weight and height and vital signs and blood pressure, as well as blood draw for DNA will occur on the Visit 2, which will be the first study visit for these participants. If a clinical OGTT had been performed prior to but within 6 months of starting the combination therapy, this OGTT can be used in analysis of the data, although will not have the full amount of data as the study OGTT. 