An Exploratory Study of RD140 Injection in Patients With Relapsed/Refractory Multiple Myeloma or Plasma Cell Leukemia

"This study is divided into two stages: dose escalation and dose extension. The dose escalation stage sampled the 3+3 dose-escalation design, and set up three dose-increasing dose groups of 1.0×10\^5 CART cells/kg, 3.0×10\^5 CART cells/kg and 6.0×10\^5 CART cells/kg, and subjects will receive a single infusion of RD140. Each dose group level will include 3-6 subjects.~In the dose expansion stage, 1\~2 dose groups were selected for expansion and 3\~6 subjects were included in each extended dose group, and the target dose was administered once."