Merck & Co. has committed $30 million to a collaboration with the Coalition for Epidemic Preparedness Innovations to develop an updated version of its recombinant vesicular stomatitis virus–based Ebola vaccine. The five-year program will focus on reducing manufacturing costs and improving thermostability to facilitate distribution in low- and middle-income countries, which account for over 90% of Ebola outbreaks. By employing a streamlined single-dose regimen and leveraging novel adjuvant formulations, Merck aims to cut production expenses by up to 40% and increase annual output capacity from 1 million to 1.5 million doses by 2028. The initiative also includes training partnerships in West and Central Africa to strengthen local cold-chain infrastructure and ensure rapid deployment in future outbreaks.

In partnership with Moderna, Merck’s anti-PD-1 therapy Keytruda achieved a 49% reduction in melanoma recurrence or death at five years follow-up in the Phase 2b KEYNOTE-942 trial. The personalized mRNA vaccine intismeran autogene, when combined with Keytruda, maintained the benefit observed at the three-year analysis, underscoring the durability of the immune response. With approximately 112,000 new melanoma cases projected in the U.S. this year, Jefferies analysts estimate peak annual sales for the combination could exceed $3 billion. Merck has also fully enrolled its Phase 3 adjuvant melanoma trial (INTerpath-001) and is advancing five additional Phase 2/3 studies across lung, bladder and renal cancers, aiming to broaden Keytruda’s label and capture an expanded oncology market.

Merck’s flagship HPV vaccine, Gardasil, continues to face headwinds as sales in China and Japan slipped by 28% and 15% respectively during the third quarter, according to company disclosures. Global Gardasil revenues dropped 12% year-over-year, reflecting waning demand in markets that previously drove double-digit growth. With Asia-Pacific now accounting for 35% of Gardasil’s global sales, analysts at Barclays warn the shortfall could shave up to $400 million from Merck’s full-year vaccine revenues. Management has signaled incremental promotional investments and new dosing schedules may be required to stabilize uptake, but consensus forecasts project fourth-quarter vaccine revenues to grow by no more than 2% unless momentum returns in key emerging markets.