Lyell Immunopharma LYL273 Trial Update

Lyell Immunopharma announced an update on the safety profile of its CAR T-cell therapy, LYL273, in an ongoing U.S. Phase 1 clinical trial for relapsed or refractory metastatic colorectal cancer. The company reported a significant reduction in Grade >= 2 diarrhea/colitis from 55% to 10% with the implementation of gastrointestinal prophylaxis and a standardized safety management plan. No Grade >= 3 cytokine release syndrome (CRS) or immune effector cell-associated neurotoxicity syndrome (ICANS) was observed in patients receiving prophylaxis. The Phase 1 trial has been amended to a Phase 1/2 design, allowing for seamless expansion into a potential pivotal single-arm Phase 2 trial, pending regulatory alignment with the United States — Food and Drug Administration. New cohorts, including a second-line cohort and a combination strategy with radiotherapy, have been added. Additional Phase 1 clinical data and an End-of-Phase 1 meeting with the United States — Food and Drug Administration are expected in the second half of 2026.