Merck and Moderna reported median five-year follow-up data from the Phase 2b KEYNOTE-942/mRNA-4157-P201 study of intismeran autogene plus Merck’s Keytruda in high-risk stage III/IV melanoma patients. The combination reduced the risk of recurrence or death by 49% versus Keytruda alone, matching the benefit seen at the three-year mark. The personalized mRNA therapy encodes up to 34 patient-specific neoantigens, and its safety profile remained consistent with earlier reports. With roughly 112,000 new U.S. melanoma cases projected in 2026, Jefferies analysts estimate peak annual sales in melanoma could reach several billion dollars if pricing aligns with Keytruda’s $200,000 per course.

Merck and the Coalition for Epidemic Preparedness Innovations (CEPI) have committed $30 million to develop an updated version of Merck’s Ebola vaccine, focusing on cost reduction and improved thermostability for low- and middle-income countries. The collaboration will fund formulation optimization, scale-up of manufacturing processes and stability testing under tropical conditions. CEPI’s support aims to secure advanced purchase commitments from global health agencies, targeting an annual production capacity of at least 5 million doses at a cost below $5 per dose.

Merck faces headwinds as Gardasil sales in China fell more than 35% year-over-year and Japanese volumes dropped by 28% in the third quarter, driven by increased competition from domestic HPV vaccines and tighter reimbursement policies. Analysts forecast vaccine segment growth could slow to low single digits in Q4, potentially dragging overall revenue guidance down by $150 million. Merck’s management has indicated plans to adjust marketing investments and expand patient assistance programs to bolster uptake, but near-term visibility remains uncertain.