Melanoma Vaccine Cuts Risk of Cancer Returning by 42% in Trial

Written by Kelly Crumrin

Posted on October 27, 2026

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A personalized cancer vaccine may help prevent melanoma from returning after surgery, according to promising results from a large clinical trial.

Researchers found that adding the experimental vaccine to an existing immunotherapy treatment reduced the risk of melanoma returning or death by 42 percent compared with immunotherapy alone.

The findings offer hope for people with high-risk melanoma, a type of skin cancer that can return even after surgery. However, the vaccine is still being studied and is not yet approved for routine use.

🗳️ If your doctor recommended it, would you consider joining a clinical trial testing a new melanoma treatment?

Yes

I’m not sure

How Does the Melanoma Vaccine Work?

Unlike vaccines that prevent infections, this cancer vaccine is designed for people who have already been diagnosed with melanoma. Known as intismeran, the vaccine uses messenger RNA (mRNA) technology to help the immune system recognize and attack cancer cells that may remain after surgery.

The treatment is personalized. This means that researchers analyze cancer cells from an individual’s tumor to identify specific genetic changes. They then use that information to create a vaccine designed specifically for their cancer.

The vaccine is given alongside pembrolizumab (Keytruda), an immunotherapy drug that helps the immune system fight cancer. The two treatments work in different ways to help the body recognize and attack melanoma cells.

What Did the Melanoma Vaccine Study Find?

The phase 3 clinical trial, called INTerpath-001, included 1,137 people with stage 2B to stage 4 melanoma. All participants had undergone surgery to remove their cancer but were considered at high risk of it returning.

Participants received either the personalized vaccine plus pembrolizumab or pembrolizumab alone.

After two years:

82 percent of people who received the vaccine and immunotherapy were alive without their melanoma returning
70 percent of people who received immunotherapy alone were alive without their melanoma returning

That means about 12 more people out of every 100 were alive without their melanoma returning after two years when they received the combined treatment.

Researchers also found that the vaccine combination reduced the risk of melanoma spreading to distant parts of the body or death. After two years, 88.5 percent of people receiving both treatments were alive without distant spread, compared with 80.2 percent receiving immunotherapy alone.

“The transformative INTerpath-001 results have the potential to make a foundational shift in how we treat patients with earlier-stage melanoma in the adjuvant [after surgery] setting.”

— Professor Georgina Long, the study’s principal investigator and medical director of Melanoma Institute Australia

Side Effects of the Melanoma Vaccine

Like all medications, the melanoma vaccine can cause side effects. The most common side effects reported by participants receiving both treatments included:

Fever
Pain at the injection site
Fatigue

Severe treatment-related side effects occurred at similar rates in both groups: 14.2 percent with the combination and 13.4 percent with immunotherapy alone.

What Does This Mean for People With Melanoma?

These findings represent an encouraging step toward new treatment options for people with melanoma who have a high risk of recurrence.

However, researchers still need to understand how long the vaccine’s benefits last and whether it helps people live longer. The vaccine must be reviewed and approved by the U.S. Food and Drug Administration before it can be offered routinely in the United States.

Talk to Your Doctor About Clinical Trials

If you’re living with melanoma, you can ask your cancer care team about your risk of recurrence, available treatments, and whether any clinical trials may be an option for you.

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