This study is a randomized, double-blind, placebo-controlled, multicenter, dose-escalating study to characterize the safety (including the anti-drug antibodies(ADA)), tolerability pharmacokinetics (PK) and pharmacodynamic parameters（PD）of TG103. The study will consist of 3 periods: an approximately 2-week lead-in period, followed by a 12-week treatment period, and a 3-week safety follow-up period. Three dose groups (7.5mg, 15mg and 22.5mg) of subjects will be enrolled and dosed sequentially; 12
The main purpose of this study is to assess the safety and tolerability of multiple ascending doses of TG103 in subjects with type 2 diabetes.