CAR‐T‐cell products in solid tumors: Progress, challenges, and strategies

Abstract T cells engineered to express chimeric antigen receptors (CARs) with specificity toward tumor cells have led to promising outcomes in patients with hematological malignancies. Nevertheless, the application of CAR‐T cell therapy in solid tumors encounters several obstacles. These include tumor heterogeneity and immune escape, T cell exhaustion and restricted infiltration into the tumors that affect the therapeutic efficacy of CAR‐T cells, as well as “on‐target, off‐tumor” toxicities that can lead to severe and even fatal adverse events. In recent years, clinical trials and new approaches of CAR‐T cell therapy for solid tumors have made certain progress. Here, we update the outcomes of related clinical trials and summarize engineered strategies aiming to improve the efficacy and therapeutic safety of CAR‐T cells based on experimental and clinical studies.