CEL-SCI Highlights FDA Approval Of Merck's Keytruda As Precedent For Multikine, Citing 66% Reduction In Risk Of Death In Low/Zero PD-L1 Head And Neck Cancer Patients vs. Keytruda's 30% Recurrence Reduction In PD-L1 Positive Tumors

FDA priority review and approval based on interim results sets a positive precedent, paving the path for future Multikine approval

Multikine reduced the risk of death by 66% compared to standard of care in the target population of patients with low and zero PD-L1, while Keytruda reduced the risk of recurrence and progression (EFS) by 30% compared with standard of care in patients whose tumors expressed higher PD-L1 without demonstrating improvement in overall survival

Pre-operative treatments from CEL-SCI and Merck have the potential to offer clinical benefit for locally advanced resectable head and neck cancer patients across the PD-L1 expression spectrum

CEL-SCI Corporation (NYSE:CVM) today applauded the U.S. Food and Drug Administration's (FDA) approval of Merck's KEYTRUDA® (pembrolizumab), an anti-PD-1 therapy, for the treatment of adult patients with resectable locally advanced head and neck squamous cell carcinoma (HNSCC) whose tumors express PD-L1 (Combined Positive Score [CPS] ≥1) as determined by an FDA-approved test. Merck's application was granted the FDA's priority review on February 25, 2025, and regulatory approval was granted on June 13, 2025, based on interim results from Keytruda's Phase 3 KEYNOTE-689 trial.

Last week the FDA approved Keytruda as a perioperative (before and after surgery) treatment for resectable locally advanced head and neck cancer patients whose tumors express PD-L1 at a positive level. In Merck's Phase 3 KEYNOTE-689 trial, Keytruda reduced the risk of recurrence and progression by 30%, compared with standard of care, in patients whose tumors expressed PD-L1 (CPS ≥1). The study did not show an improvement in overall survival. Patients with low to zero levels of PD-L1 did not benefit from Keytruda.

In contrast to the results of the KEYNOTE-689, CEL-SCI's Phase 3 study showed that Multikine* treated patients whose tumors expressed low (Tumor Proportion Score [TPS <10]) to zero PD-L1, had their risk of death reduced by 66% (hazard ratio 0.34, 95% CI [0.18, 0.65], p=0.0012) and extended the 5-year overall survival to 73% compared to 45% in the standard of care, log rank p=0.0015. About 70% of the patients in CEL-SCI's Phase 3 study had low to zero levels of PD-L1.