Safety Study of CC312 in Autoimmune Disease Patients

This study is an open-label, multiple-dose escalation, Investigator-Initiated Trial (IIT) clinical trial designed to evaluate the safety and tolerability of CC312 in adult patients with relapsed and refractory autoimmune diseases. The trial also assesses pharmacokinetics (PK) and preliminary efficacy. CC312 is a trispecific T cell engager (TriTE) that targets the B cell surface antigen CD19, the T cell antigen CD3, and the T cell co-stimulatory molecule CD28. Given its mechanism of action, which is similar to the "biopharmaceutical version" of CAR-T, there is a higher risk of cytokine release syndrome (CRS) at the onset of infusion administration. Therefore, a lower priming dose will be administered before the therapeutic dosing phase to mitigate this risk and ensure safety, followed by a therapeutic dose to achieve and maintain efficacy. The study is divided into three dose groups, with 3-6 subjects enrolled in each group, resulting in a total of 9-18 subjects in the study. A "3+3" dose escalation design is employed to systematically evaluate the safety and determine the optimal dose of CC312.