Merck (NYSE: MRK) and Moderna (NASDAQ: MRNA) Announced Wednesday August 19, 2026 That the Phase 3 INTerpath-001 Trial of Intismeran Autogene (V940 / mRNA-4157, an Individualized Neoantigen Therapy) Plus Pembrolizumab (Keytruda) Met Its Primary Endpoint of Recurrence-Free Survival (RFS) and Key Secondary Endpoint of Distant Metastasis-Free Survival (DMFS) in Adults With High-Risk (Stage IIB-IV) Resected Cutaneous Melanoma Compared to Keytruda Alone; The Readout Is the First Positive Phase 3 for an Individualized Neoantigen Therapy and the First Phase 3 to Demonstrate Substantial Improvement Over Keytruda Alone in the Adjuvant Melanoma Setting; Phase 2b KEYNOTE-942 Five-Year Follow-Up Data Presented at ASCO 2026 Had Shown a 49% Reduction in Risk of Recurrence or Death and a 59% Reduction in Risk of Distant Metastasis or Death Versus Keytruda Alone
Merck (NYSE: MRK) and Moderna (NASDAQ: MRNA) announced Wednesday August 19, 2026 that the Phase 3 INTerpath-001 trial of intismeran autogene (V940 / mRNA-4157, an individualized neoantigen therapy) plus pembrolizumab (Keytruda) met its primary endpoint of recurrence-free survival (RFS) and the key secondary endpoint of distant metastasis-free survival (DMFS) in adults with high-risk (Stage IIB-IV) resected cutaneous melanoma compared to Keytruda alone. Mechanism: intismeran autogene is a personalized mRNA therapy that encodes up to 34 tumor-specific neoantigen peptides selected from the individual patient's tumor mutation signature. The mRNA is delivered as a lipid nanoparticle injection; cells at the injection site translate the mRNA into the neoantigen peptides, which are then presented to the immune system to generate a targeted T-cell response against the patient's tumor. The Phase 3 readout is the first positive Phase 3 for an individualized neoantigen therapy and the first Phase 3 to demonstrate substantial improvement over Keytruda alone in the adjuvant melanoma setting. Trial design: randomized, double-blind, placebo- and active-comparator-controlled global Phase 3 evaluating safety and efficacy of the combination versus Keytruda alone. Phase 2b KEYNOTE-942 five-year follow-up data presented at the 2026 ASCO Annual Meeting had shown a 49% reduction in risk of recurrence or death and a 59% reduction in risk of distant metastasis or death for the combination versus Keytruda alone, and the Phase 3 readout confirms and extends those benefits. The result validates the personalized neoantigen mRNA vaccine platform and opens a substantial commercial pathway for the Merck-Moderna collaboration in adjuvant oncology settings beyond melanoma including non-small-cell lung cancer, renal cell carcinoma, and cutaneous squamous cell carcinoma where INTerpath studies are ongoing.