SOUTH SAN FRANCISCO, Calif. — November 10, 2025 — Leads & Copy — Lyell Immunopharma, Inc. (Nasdaq: LYEL) has bolstered its solid tumor pipeline through the acquisition of global rights to LYL273, a novel autologous guanylyl cyclase-C (GCC)-targeted CAR T-cell product candidate, from Innovative Cellular Therapeutics (ICT) for the treatment of metastatic colorectal cancer (mCRC) and other GCC-expressing cancers.
The acquired LYL273 (formerly GCC19CART) demonstrated a 67% overall response rate and an 83% disease control rate in patients with refractory mCRC enrolled in an ongoing Phase 1 clinical trial in the U.S., with a manageable safety profile at the highest dose level studied.
LYL273 is designed to improve CAR T-cell expansion, immune cell infiltration and cancer cell killing in the hostile solid tumor microenvironment. The U.S. Food and Drug Administration granted Fast Track designation to LYL273 for mCRC treatment.
According to Benjamin L. Schlechter, MD, Senior Physician in the Gastrointestinal Cancer Center, Dana-Farber Cancer Institute, the outcomes in the initial cohort of heavily pre-treated patients are encouraging. He added that patients with metastatic colorectal cancer have a significant need for innovations like LYL273.
Richard Klausner, MD, Lyell co-founder and Board Chairman, stated that these early results suggest they may be on the path to breaking the barrier for solid cancer CAR T-cell therapy. He further noted that the ability to treat solid tumors with an acceptable safety profile has become the holy grail for CAR T-cell therapy for cancer.
As of the October 28, 2025 data cutoff date, the Phase 1 clinical trial data reported dose-dependent clinical activity in 12 patients. Six patients received Dose Level 1 (1 x 106 CAR T cells/kg), and six patients received Dose Level 2 (2 x 106 CAR T cells/kg). Across both dose levels, the overall response rate was 50%, and the disease control rate was 83%.
At Dose Level 2, the overall response rate was 67%, with one patient achieving a pathological complete response and one patient showing complete tumor volume reduction of the target lesions. The disease control rate was 83%, and the median progression-free survival was 7.8 months. The incidence and severity of treatment-related adverse events were higher at Dose Level 2.
The most common treatment-related adverse events at Dose Level 2 were cytokine release syndrome (83%) and diarrhea (83%). Immune effector cell-associated neurotoxicity syndrome occurred in 33% of patients and resolved rapidly with treatment. A dose-limiting toxicity occurred in one patient, including Grade 3 diarrhea, Grade 4 enterocolitis and death from fungal sepsis 48 days post-infusion.
According to Lynn Seely, MD, Lyell’s President and CEO, Lyell was founded to realize the full potential of cell therapy for solid tumors, and LYL273 has the potential to be a transformational advance in the treatment of colorectal cancer.
Lyell will receive exclusive global rights, outside of mainland China, Hong Kong, Macau and Taiwan, to research, develop, manufacture and commercialize LYL273. ICT will receive an upfront payment of $40 million and 1.9 million shares of Lyell common stock. Additionally, ICT is eligible for up to $30 million in clinical milestones, $115 million in regulatory milestones, and $675 million in commercial sales milestones, as well as tiered royalties.
Lyell expects its cash will be adequate to fund operations into 2027 through data and progress updates from the ronde-cel clinical program and additional clinical data from the Phase 1 clinical trial of LYL273. Lyell expects net cash use in 2025 to be between $155 million and $160 million, excluding the $40 million upfront payment from the transaction.
Lyell’s management hosted an investor conference call and webcast, which can be replayed on the Investor page of the Lyell Website.
Ellen Rose
Senior Vice President, Communications and Investor Relations
erose@lyell.com
Source: Lyell Immunopharma, Inc.
