This is a multicenter, randomized, double-blind and placebo-controlled study. The investigational drug is HBM9161 injection, with the indication of TED. Subjects will be randomized to treatment group I, treatment group II, or placebo group. Subjects in treatment group 1 will receive HBM9161 680 mg subcutaneously once weekly (qw) for 12 doses; Subjects in treatment group 2 will receive HBM9161 680 mg subcutaneously once weekly (qw) for 6 doses, followed by HBM9161 680 mg subcutaneously once every two weeks (q2w) for 3 doses; Subjects in placebo group will receive placebo subcutaneously once weekly (qw) for 12 doses. After the 12-week dosing period, there will be a 5-week follow-up period.
Primary Objective: To preliminarily evaluate the efficacy of the treatment regimen of HBM9161 680 mg administered subcutaneously weekly and sequentially every other week for 12 weeks in Chinese patients with active moderate to severe TED.