Cell therapy developer Lyell has initiated a first‑of‑its‑kind trial that tests its experimental CAR‑T product directly against marketed CAR‑T therapies. The head‑to‑head design aims to generate comparative efficacy and safety data rather than the traditional single‑arm registration pathway. The study could reset competitive benchmarks in autologous cell therapy if Lyell demonstrates superior durability or safety. Investors and clinical stakeholders will watch trial design, endpoints and comparator selection closely, since regulators and payers increasingly demand comparative effectiveness data to inform coverage decisions.