A study published in the New England Journal of Medicine presents the use of universal base-engineered CAR7 T cells for the treatment of relapsed T-cell acute lymphoblastic leukemia (T-ALL). These CAR7 T cells are genetically engineered using base editing that inactivates the genes CD52, CD7, and the β chain of the αβ T-cell receptor, thereby reducing the risk of rejection, cell fratricide, and graft-versus-host disease. Ten patients, including children and adults with relapsed T-ALL who did not respond to standard therapy, were treated in clinical phase 1. In 82% of patients there was a deep remission, which enabled subsequent allogeneic stem cell transplantation. After three years, 64% of patients remain disease-free. Serious adverse events included cytokine release syndrome, multiple cytopenias, and opportunistic infections, with fatal fungal complications in one patient. The results support further research into this therapy as a potentially effective option for patients with relapsed T-ALL[1][2].