However, another clinical study has indicated that compared to CD19‐targeted CAR‐T cell therapy alone, patients receiving vancomycin pretreatment before CAR‐T cell therapy achieved significantly enhanced tumor control effects, a phenomenon possibly related to increased cross‐presentation of tumor‐associated antigens, suggesting that vancomycin‐modulated gut microbiome composition may constitute one of the key factors influencing the efficacy of CAR‐T cell immunotherapy [232]. The gene discussed is CD19; the disease is neoplasm.