Weill Cornell Medicine and Roswell Park reported preclinical evidence that directly delivering CAR T cells into the bladder can control bladder tumors. In a Journal of Experimental Medicine study, researchers co-led by Taha Merghoub, PhD, identified MUC16 as a clinically relevant target for bladder cancer and demonstrated tumor control in mice using intravesical, catheter-based administration of MUC16-targeting CAR T cells. The investigators emphasized that shifting CAR T delivery from systemic to local administration aims to address solid-tumor barriers such as poor infiltration and off-target toxicity, leveraging an established urology route for potential bladder-sparing benefit. While the work remains preclinical, it establishes both the target rationale (MUC16) and an administration strategy (intravesical delivery) that could shape how next CAR T concepts are translated toward early human studies.