In vivo CAR therapy: quo vadis?

In vivo CAR therapies are rapidly emerging as a strategy to address the scalability, access, and toxicity limitations associated with conventional ex vivo CAR-T cell products. This article reviews viral and LNP–RNA platform technologies, emerging clinical evidence, and key safety and regulatory considerations relative to established CAR-T and immune cell engager approaches. While early progress is encouraging, careful translational evaluation is essential to determine whether in vivo CAR strategies can ultimately meet or surpass current standards of care across oncology, autoimmunity, and other indications.