Efficacy and Safety of CAR T-cell Therapy in Relapsed/Refractory B-cell Acute Lymphoblastic Leukemia: A Systematic Review and Meta-analysis

IntroductionAcute lymphoblastic leukemia (ALL) is the most common childhood cancer, with rising global incidence. The prognosis for patients with relapsed or refractory B-cell ALL (r/r B-ALL) remains poor, necessitating novel therapies. Chimeric Antigen Receptor T-cell (CAR T-cell) therapy has shown promise in treating r/r B-ALL, offering significant improvements in remission rates. MethodsA comprehensive literature search was conducted across PubMed, Embase, and Cochrane Library for studies evaluating CAR T-cell therapy in r/r B-ALL. Randomized controlled trials, cohort, and case-control studies were included, focusing on efficacy and safety outcomes. Data were extracted and pooled using random-effects models. The risk of bias was assessed with the New Ottawa Scale. ResultsA total of 32 studies were included, involving 1,55,365 patients. The pooled relapse rate was 0.39 (95% CI: 0.29-0.49), with no significant difference between CD19 and CD22 CAR T-cell therapies (p = 0.88). Co-stimulatory agents like 4-1BB showed the most favorable relapse rate of 0.38 (95% CI: 0.27-0.49). The overall Cytokine Release Syndrome (CRS) rate was 0.63 (95% CI: 0.53-0.73), and neurotoxicity occurred at a rate of 0.32 (95% CI: 0.24-0.41). ConclusionCAR T-cell therapy is effective in treating r/r B-ALL, with high remission rates and manageable adverse events. The choice of co-stimulatory agent and antigen target influences relapse outcomes. Further research is needed to refine CAR T-cell constructs and optimize patient-specific treatments.