A Study of Efficacy and Safety of Supaglutide in Type 2 Diabetes Patients On Metformin Treatment(SUPER-2)

This is a study to evaluate the efficacy and safety of Supaglutide injection in the treatment of type 2 diabetes patients with poor glycemic control after metformin treatment. This trial includes dosage determination (Phase IIb) and efficacy confirmation stage(Phase III ). The primary outcome of the phase IIb period is to preliminarily evaluate the efficacy and safety of Supaglutide combined with metformin and to provide the recommended dosage for the Phase 3 period after 12-week treatment. The primary outcome of the Phase III period is to evaluate the efficacy and safety of Supaglutide combined with metformin treatment after 24-week, double-blind treatment. The secondary outcome is to evaluate the efficacy and safety of Supaglutide combined with metformin during the 24-week, double-blinded plus 28-week, open-label treatment period.

This trial includes a 2-week screening period, a 4-week metformin titration and dose-stabilization period, a 4-week induction period, a 24-week double-blind treatment period and a 28-week open-label treatment period, followed by a 4-week follow-up period and a follow-up visit. We calculated that the sample size would need to be 632, including 120 subjects in the period of Phase IIb and 512 subjects in the period of Phase III. During the phase IIb period, subjects were randomly assigned to once-weekly subcutaneously injected Supaglutide 1mg plus metformin, 3mg plus metformin and placebo plus metformin at a ratio of 1:1:1. When the number of participants who have completed the 12-week follow up reached 120, interim analyses will be performed and the results will be evaluated by Independent Data Monitoring Committee experts to determine the recommended phase 3 dosage. During the phase III stage, subjects were randomly assigned 1:1 to the "recommended phase 3 dosage + metformin" group and the "placebo + metformin" group.