Headline Roundup • August 19th, 2026
Personalized mRNA Vaccine Reduces Risk of Melanoma Recurrence in Clinical Trials
Summary from the AllSides News Team
A personalized mRNA vaccine combined with Keytruda immunotherapy, developed by Moderna and Merck, successfully prevented skin cancer from recurring or spreading in patients during a phase 3 clinical trial.
The Details: Each vaccine is designed "specifically for each patient based on the unique set of mutations within their tumor to train and activate the immune system to recognize and fight cancer," according to Moderna and Merck. The trial enrolled 1,137 high-risk patients that had surgically removed melanoma. The patients were randomized, with half receiving Keytruda immunotherapy plus the mRNA vaccine and half receiving just Keytruda. In January, the companies announced at the mid-stage of the trial that the vaccine reduced the risk of recurrence of cancer or death by 49% after five years. Shares in Moderna went up 60% in premarket trading after the announcement.
For Context: The National Cancer Institute found that in 2023, 1.5 million Americans were living with melanoma, which is the deadliest form of skin cancer. mRNA vaccines were first made available to the public during the COVID-19 pandemic, and since then, the US Food and Drug Administration (FDA) has approved other mRNA vaccines for the flu and respiratory syncytial virus (RSV).
How the Media Covered It: CNN (Lean Left bias) focused on the stock market gains for the companies, noting that "Barclays analysts said they expect the therapy could generate about $3 billion for treating melanoma by 2035." Reuters (Center) reported that Moderna "struggled to generate new products beyond its COVID-19 vaccine and faced pushback over its mRNA technology from President Donald Trump's administration," making this new vaccine a potential "reversal of fortune" for the company. Epoch Times (Lean Right) highlighted views from supporters and critics of mRNA vaccines, writing that proponents "say the technology is superior to older vaccine platforms, in part because it can be quickly reconfigured," while critics are concerned about potential "serious side effects, including cancer."
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A cancer vaccine utilizing messenger ribonucleic acid (mRNA) technology prevented skin cancer from recurring in a phase 3 clinical trial, companies that make the vaccine said on Aug. 19.
The trial participants were people who underwent surgery to remove skin cancer.
The vaccine also prevented cancer from spreading in the patients, Moderna and Merck said.
Moderna's mRNA vaccine combined with Merck's immunotherapy Keytruda succeeded in a late-stage trial for skin cancer, the companies said on Wednesday, sending shares of the vaccine maker up 60% in premarket trading.
The study is ongoing, but interim results found the treatment, Intismeran, met both its primary target of reducing cancer recurrence and its secondary goal of keeping cancers from spreading to other parts of the body.
Moderna said on Wednesday that a personalized mRNA cancer vaccine reduced the risk of recurrence and spread of melanoma in a late-stage trial, a major success in a new field of cancer treatment that sent the drugmaker's shares surging as much as 160%.
Moderna developed the vaccine with Merck and tested it together with immunotherapy drug Keytruda, a widely used treatment for melanoma. Thousands of patients who have undergone surgery to remove high-risk melanoma tumors could benefit as soon as next year if regulators approve the vaccine, Moderna President Stephen...
