A Clinical Study of TQB2029 for Injection in Subjects With Multiple Myeloma

This is a study to evaluate the maximum tolerated dose (MTD), dose limiting toxicity (DLT), occurrence of all adverse events (AEs) and serious adverse events (SAEs), pharmacokinetic parameters, pharmacodynamic parameters, immunogenicity, and anti-tumor effects of TQB2029 for injection in Chinese adult subjects with multiple myeloma. The study is divided into Phase Ia and Ib, Phase Ia: dose escalation phase, to evaluate the safety and tolerability of TQB2029 for injection, and determining DLT and MTD; Phase Ib: Dose extension phase, to evaluate the effectiveness of TQB2029 for injection in subjects with multiple myeloma.