Merck, Moderna say mRNA vaccine and Keytruda lowers the risk of death in melanoma patients

Merck & Co. Inc. and Moderna Inc. said Tuesday that their experimental mRNA-based cancer vaccine reduced the risk of recurrence or death when used with Merck’s Keytruda in patients with late-stage melanoma. Merck’s stock was up 1.9% in premarket trading, while Moderna shares rallied 5.6%. The Phase 2b study compared the combination treatment with Keytruda. The companies said they now plan to move forward with a Phase 3 clinical trial testing the combination treatment in 2023, and they also plan to study how the mRNA vaccine/Keytruda combination can be used to treat other types of tumors. Merck’s stock has gained 42.2% year-to-date, while Moderna’s shares are down 34.9%. The S&P 500 has declined 16.2% so far this year.

Market Pulse Stories are Rapid-fire, short news bursts on stocks and markets as they move. Visit MarketWatch.com for more information on this news.