8-K: Lyell Immunopharma Reports Promising Initial Data from Phase 1 Trial of LYL797 CAR T-Cell Therapy

Lyell Immunopharma announced positive initial clinical data from its Phase 1 trial of LYL797, a CAR T-cell therapy, showing dose-dependent anti-tumor activity and tumor infiltration in patients with advanced solid tumors.

Summary

• Lyell Immunopharma has released initial clinical and translational data from its Phase 1 trial of LYL797, a CAR T-cell therapy targeting the ROR1 protein.
• The trial included 20 patients with advanced solid tumors, primarily triple-negative breast cancer (TNBC) and non-small cell lung cancer (NSCLC), all with relapsed or refractory metastatic disease.
• Patients had received a mean of six prior lines of therapy for metastatic disease.
• Four dose levels of LYL797 were explored: 50 x 10^6, 100 x 10^6, 150 x 10^6, and 300 x 10^6 cells.
• In 16 efficacy-evaluable patients, the objective response rate (ORR) was 40% and the clinical benefit rate (CBR) was 60% at the 150 x 10^6 cell dose level for TNBC patients.
• Across all dose levels, the CBR was 38%.
• The most frequent adverse events were cytokine release syndrome (61%), pneumonitis (22%), and headache (17%).
• Grade 3 related adverse events included pneumonitis (17%) and hypoxia (11%).
• One patient experienced Grade 5 respiratory failure.
• No immune effector cell-associated neurotoxicity syndrome (ICANS) was reported.
• Translational data showed that LYL797 CAR T-cells expanded, infiltrated, and persisted in solid tumors, with evidence of tumor killing.
• CAR T-cell expansion was observed in peripheral blood samples at Day 60 in all patients assessed, with peak expansion between Days 8 and 11.
• The exhaustion marker TIGIT was low in LYL797 CAR T-cells at Day 11.
• LYL797 CAR T-cells were present in all evaluable solid-tumor biopsies.
• The company has submitted an IND for LYL119, a next-generation ROR1-targeted CAR T-cell product.

Sentiment

Score: 8

Explanation: The document presents positive initial clinical data with promising efficacy and tumor infiltration, although there are some safety concerns that need to be managed. The company's cash runway is also a positive factor.

Positives

• LYL797 showed dose-dependent anti-tumor activity in patients with advanced solid tumors, particularly TNBC.
• The therapy demonstrated a 40% objective response rate at the highest dose level cleared to date.
• LYL797 CAR T-cells successfully infiltrated solid tumors and showed evidence of tumor killing.
• The manufacturing success rate for LYL797 was 100%.
• The company is expanding the trial to include patients with other ROR1-expressing tumors, such as ovarian and endometrial cancers.
• The company has submitted an IND for LYL119, a next-generation ROR1-targeted CAR T-cell product.

Negatives

• Pneumonitis was a notable adverse event, particularly in patients with lung metastases, with one patient experiencing Grade 5 respiratory failure.
• Cytokine release syndrome (CRS) was a common adverse event, although generally mild.
• Dose escalation is being conducted separately for patients with and without lung involvement due to the pneumonitis risk.

Risks

• The risk of pneumonitis, especially in patients with lung metastases, requires careful monitoring and management.
• The long-term durability of the responses observed with LYL797 needs further evaluation.
• The company is still in the early stages of clinical development, and there are risks associated with clinical trials and regulatory approvals.
• The company's ability to manufacture and supply its product candidates for clinical trials is a risk.

Future Outlook

Lyell plans to continue dose escalation of LYL797, expand the trial to include patients with other ROR1-expressing tumors, and initiate a new clinical trial for patients with multiple myeloma and chronic lymphocytic leukemia. They also plan to advance LYL119, their next-generation ROR1-targeted product candidate.

Management Comments

• David R. Spigel, MD, stated that the initial findings are promising and demonstrate the potential of LYL797 to deliver meaningful benefits to patients.
• Lynn Seely, MD, expressed encouragement with the clinical responses and the demonstration of persistent CAR T-cell infiltration into solid tumors.

Industry Context

This announcement is significant in the context of the broader cell therapy field, as it demonstrates the potential of CAR T-cell therapy to address solid tumors, which have been more challenging to treat than hematological malignancies. The use of anti-exhaustion technology is also a key area of innovation in the field.

Comparison to Industry Standards

• The 40% ORR in TNBC at the 150 x 10^6 dose level is competitive with other CAR T-cell therapies in solid tumors, although direct comparisons are difficult due to differences in patient populations and trial designs.
• The ability of LYL797 to infiltrate solid tumors is a key differentiator, as this has been a challenge for many CAR T-cell therapies.
• The management of pneumonitis is consistent with the standard of care for other cancer therapies that have this side effect.
• Companies like Kite Pharma and Novartis have had success with CAR T-cell therapies in hematological malignancies, but solid tumors remain a significant unmet need, making Lyell's progress noteworthy.

Stakeholder Impact

• Shareholders may react positively to the promising clinical data.
• Patients with advanced solid tumors may benefit from this new treatment option.
• Employees may be motivated by the progress of the company's research.
• The company's suppliers and partners may see increased business opportunities.

Next Steps

• Select a Recommended Phase 2 Dose for LYL797.
• Generate data at higher dose levels.
• Continue dose escalation with steroid prophylaxis in patients with lung involvement.
• Enroll patients with platinum-resistant ovarian and endometrial cancers.
• Initiate a study in hematologic malignancies including multiple myeloma and CLL.
• Advance LYL119 into clinical trials.

Key Dates

Keywords

CAR T-cell therapy, LYL797, ROR1, Triple-negative breast cancer, Solid tumors, Immunotherapy, Anti-exhaustion technology, Clinical trial, Pneumonitis, Cytokine release syndrome