IL15 and graft versus host disease: Rezvani et al. in a clinical trial initiated in 2017 (NCT03056339), reported in 2020 phase I interim results.90 These showed that cord blood CAR-NK-CD19 cells armored with soluble IL-15 could persist in patients for over a year with a single infusion, with an overall response rate (ORR) of 73% and achieving complete remission (CR) for seven out of eleven patients, without any cytokine related syndrome (CRS), graft versus host disease (GVHD), Immune effector cell-associated neurotoxicity syndrome (ICANS) or NK-related toxicity as.