Complete immune reconstitution was achieved by 24 months post-transplantation, with sustained functional immune recovery and a Functional Assessment of Cancer Therapy-Leukemia (FACT-Leu) total score of 158/172 at the 7-year follow-up.<h4>Conclusions</h4>This case report details the clinical course of an adult patient with early-relapsed, chemorefractory B-ALL who achieved 7-year MRD-negative sustained remission after treatment with PD-L1-armored CD19/CD22 dual-targeted CAR-T cell co-infusion followed by consolidative allo-HSCT. Here, CD274 is linked to acute lymphoblastic leukemia.