KYS202002A

Main objectives: 1. To evaluate the safety and tolerability of intravenous administration of KYS202002A in subjects with relapsed or refractory multiple myeloma; 2. To determine the dose-limiting toxicity (DLT) and maximum tolerated dose (MTD) of intravenous administration of KYS202002A in subjects with relapsed or refractory multiple myeloma, and to provide a basis for the dosing regimen and dosage of Phase II clinical trials. Secondary objectives: 1. To evaluate the pharmacokinetic and pharmacodynamic characteristics of KYS202002A in subjects with relapsed or refractory multiple myeloma; 2. To evaluate the immunogenicity of KYS202002A in subjects with relapsed or refractory multiple myeloma; 3. To preliminarily evaluate the anti-tumor activity of KYS202002A in subjects with relapsed or refractory multiple myeloma.