By — Associated Press Associated Press Leave your feedback Share Copy URL https://www.pbs.org/newshour/health/moderna-shares-surge-after-it-says-experimental-mrna-cancer-treatment-passed-key-test Email Facebook Twitter LinkedIn Pinterest Tumblr Share on Facebook Share on Twitter Moderna shares surge after it says experimental mRNA cancer treatment passed key test Health Aug 20, 2026 10:49 AM EDT Moderna shares more than doubled Wednesday after it announced initial results from a study of an experimental cancer treatment that would be the first of its kind if approved by regulators. READ MORE: Flight attendants and pilots have highest risk of dying from radiation-linked cancers, study says Moderna and Merck are developing a treatment using an mRNA-based cancer vaccine called intismeran that is designed to be tailored to individual patients based on unique mutations within their tumors. In current studies, they are pairing it with Keytruda, a immunotherapy drug made by Merck. The study compared using intismeran and Keytruda together on melanoma patients against using Keytruda alone. The companies said patients who received the combination lived longer without cancer returning or metastasizing than patients who got Keytruda alone. Educate your inbox Subscribe to Here’s the Deal, our politics newsletter for analysis you won’t find anywhere else. Enter your email address Subscribe Form error message goes here. Thank you. Please check your inbox to confirm. The companies did not say how long patients survived without cancer returning or whether patients lived longer overall. They said they plan to present the study results at an upcoming international medical meeting. READ MORE: Trump's vaccine order would require millions of individual shots last used decades ago Moderna shares rose more than 120% to $140.12 a share. Merck shares rose about 11%. A free press is a cornerstone of a healthy democracy. Support trusted journalism and civil dialogue. Donate now By — Associated Press Associated Press
Moderna shares more than doubled Wednesday after it announced initial results from a study of an experimental cancer treatment that would be the first of its kind if approved by regulators. READ MORE: Flight attendants and pilots have highest risk of dying from radiation-linked cancers, study says Moderna and Merck are developing a treatment using an mRNA-based cancer vaccine called intismeran that is designed to be tailored to individual patients based on unique mutations within their tumors. In current studies, they are pairing it with Keytruda, a immunotherapy drug made by Merck. The study compared using intismeran and Keytruda together on melanoma patients against using Keytruda alone. The companies said patients who received the combination lived longer without cancer returning or metastasizing than patients who got Keytruda alone. Educate your inbox Subscribe to Here’s the Deal, our politics newsletter for analysis you won’t find anywhere else. Enter your email address Subscribe Form error message goes here. Thank you. Please check your inbox to confirm. The companies did not say how long patients survived without cancer returning or whether patients lived longer overall. They said they plan to present the study results at an upcoming international medical meeting. READ MORE: Trump's vaccine order would require millions of individual shots last used decades ago Moderna shares rose more than 120% to $140.12 a share. Merck shares rose about 11%. A free press is a cornerstone of a healthy democracy. Support trusted journalism and civil dialogue. Donate now