This study investigated the antitumor efficacy of IL-15-armored claudin 18.2-targeting CAR-T cells in syngeneic mouse tumor models. IL-15-armored CAR-T cells showed improved in vitro expansion and a less differentiated phenotype. In vivo, these cells demonstrated enhanced antitumor activity in both pancreatic and melanoma models, with increased in vivo expansion and tumor infiltration. The enhanced efficacy was associated with increased T-cell infiltration and a surprising increase in tumor angiogenesis. While some tumor recurrence occurred, the study suggests IL-15 armoring as a promising strategy to improve CAR-T cell therapy for solid tumors.
