Lyell Acquires LYL273 CAR-T, Reports 67% ORR in Refractory Colorectal Cancer

SOUTH SAN FRANCISCO, Calif. – November 10, 2025 — Lyell Immunopharma, Inc. (Nasdaq: LYEL), a late-stage clinical company advancing next-generation chimeric antigen receptor (CAR) T-cell therapies, today announced the acquisition of exclusive global rights (excluding Greater China) to LYL273 (formerly GCC19CART) from Innovative Cellular Therapeutics (ICT).

LYL273 is a novel autologous guanylyl cyclase-C (GCC)-targeted CAR T-cell product candidate being developed for metastatic colorectal cancer (mCRC) and other GCC-expressing cancers. The acquisition significantly strengthens Lyell’s solid tumor pipeline.

High Response Rates Observed in Difficult-to-Treat mCRC

The acquisition follows promising clinical data from an ongoing U.S. Phase 1 clinical trial of LYL273 in patients with refractory mCRC. At the highest dose level studied to date (Dose Level 2), LYL273 achieved:

• Overall Response Rate (ORR): 67% (4 of 6 patients)
• Disease Control Rate (DCR): 83% (5 of 6 patients)

The responses included one patient with a pathological complete response and another with a complete reduction in tumor volume. For patients in Dose Level 2, the median progression-free survival was 7.8 months.

“The outcomes in this initial cohort of heavily pre-treated patients are very encouraging,” said Benjamin L. Schlechter, MD, lead investigator in the Phase 1 clinical trial.

Colorectal cancer is the second leading cause of cancer deaths worldwide. GCC is an ideal target as it is expressed on more than 95% of colorectal cancers.

Enhanced CAR-T Designed to Overcome Solid Tumor Barriers

LYL273 is a GCC-targeted CAR T-cell product candidate armed with enhancements designed to improve its effectiveness in the hostile solid tumor microenvironment. These enhancements include CD19 CAR expression and controlled cytokine release, which are intended to improve CAR T-cell expansion, immune cell infiltration, and cancer cell killing.

The therapy demonstrated a manageable safety profile. LYL273 has been granted Fast Track designation by the FDA.

Transaction Details and Financial Outlook

Under the licensing agreement, Lyell gains exclusive global rights to LYL273 outside of Greater China. ICT will receive an upfront payment of $40 million cash and 1.9 million shares of Lyell common stock, and is eligible for up to $850 million in additional milestones and tiered royalties.

Lyell management expects the current cash resources will fund operations into 2027, supporting the progress of LYL273 and Lyell’s other pivotal clinical trials. The next data update from the Phase 1 trial is expected in the first half of 2026.