Moderna is announcing a breakthrough in its mRNA vaccine trial for melanoma, a type of skin cancer. According to the results from a Phase 3 clinical trial involving over 1,100 people, the vaccine showed "statistically significant and clinically meaningful improvement" in helping patients remain cancer-free for longer. The trial used a combination of Moderna's mRNA vaccine and Merck's Keytruda drug, with results indicating that patients who received the vaccine stayed cancer-free longer than those who did not. This breakthrough has caused Moderna's stock to more than double, but it is also a significant step forward in the fight against melanoma, which affects about 112,000 people in the US each year and kills around 8,500 annually.
Written by the local model on 2026-08-20,
using this article's own text rather than the other coverage of the
same event (that is the story summary below).
Story summary
Moderna, a biotechnology company, has announced promising results from a Phase 3 clinical trial of its mRNA vaccine for treating advanced-stage melanoma, the deadliest form of skin cancer. The trial, which involved over 1,100 patients, showed that the vaccine led to a statistically significant and clinically meaningful improvement in preventing melanoma recurrence or spread. This breakthrough could potentially revolutionize the treatment of melanoma, and Moderna's stock price surged by more than double on Wednesday morning after the news was announced. The vaccine works by using artificial intelligence to identify specific mutations in each patient's tumor and then delivering synthetic mRNA into cells to attack those mutations. This is a major milestone for mRNA vaccines, which have shown significant promise in treating various types of cancer, including melanoma.
Written for “Moderna Melanoma Vaccine Trial” on 2026-08-31,
grounded in this article and the 1 other(s) covering the same event.
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answer rather than a gap: a match report or a rescue can be warmly
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No political leaning scored for article 1564 · logged 2026-08-21
Moderna is touting a "landmark moment" in its
, saying its vaccine could help prevent the deadly skin cancer from returning or spreading.
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vaccine → tout → cancer
The groundbreaking clinical trial studied over 1,100 people whose melanoma was in advanced stages, taking a piece of a patient's tumor and using it to build a shot, CBS News medical correspondent Dr. Céline Gounder explained.
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Gounder → study → shot
The results came from a Phase 3 trial, the last stage before a Food and Drug Administration review.
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results → come → review
Gounder, who has had melanoma herself but noticed it very early, said the trial is "a big win for mRNA vaccines against cancer."
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trial → have → cancer
Following the news, Moderna's stock more than doubled on Wednesday morning.
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stock → follow → morning
Here's what to know about the melanoma vaccine:
How does the melanoma vaccine work?
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vaccine → know → vaccine
After a piece of the patient's tumor is removed, it is analyzed to identify the unique mutations present, CBS News chief medical correspondent Dr. Jon LaPook said.
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LaPook → remove → mutations
Artificial intelligence is then used to help scientists figure out which of the hundreds of mutations should be included in the vaccine.
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which → use → vaccine
Like other mRNA vaccines, Moderna's melanoma vaccine delivers synthetic mRNA into cells, delivering a "one-two punch" to melanoma, LaPook said.
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LaPook → deliver → melanoma
Moderna's mRNA vaccine — used in combination with Merck's cancer immunotherapy drug Keytruda — is built from a patient's own tumor, which has its own genetic sequence, so each dose is personalized.
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dose → use → sequence
"Cancer can put a cloak of invisibility around itself so the immune system can't see it, and the first punch is a drug called Keytruda, which removes the cloak," LaPook explained.
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LaPook → put → cloak
Meanwhile, the patient's cells read the mRNA and build a protein, breaking the messenger down.
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cells → read → messenger
That protein then trains the immune system to learn to attack cancer cells.
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system → train → cells
The vaccine gives the immune system the scent of melanoma so the immune system can hunt it down and kill it," LaPook said.
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LaPook → give → it
What did Moderna's melanoma vaccine trial find?
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trial → find → What
For patients whose melanoma had gone deeper, or reached the lymph nodes, Moderna and its drug development partner Merck said the novel treatment showed "statistically significant and clinically meaningful improvement" in helping patients remain cancer-free for longer.
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patients → go → improvement
For those participating in the trial, surgeons had already removed their tumors, and everyone had been treated with Keytruda, the standard immunotherapy.
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everyone → participate → Keytruda
But some patients were also given the mRNA melanoma vaccine.
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patients → give → vaccine
That group stayed cancer-free longer, the trial found.
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trial → stay → ?
about 8,500 people in the U.S. will die from melanoma this year.
is the fifth most commonly diagnosed cancer in the United States, with about 112,000 new cases each year.
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people → die → cases
The American Cancer Society projects that
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Society → project → ?
