Companies announce strong results for personalized mRNA vaccine in preventing melanoma from recurring
Tuesday, August 25, 2026

NEWS UPDATE: News organizations across the country are reporting that a personalized mRNA vaccine being tested in a late-stage clinical trial appears to prevent the return or spread of melanoma in high-risk patients.

The "topline findings” were announced by the pharmaceutical companies Moderna and Merck, who plan to present the results at an upcoming medical meeting and share them with regulatory authorities.

According to the companies’ news release, the combination of a personalized mRNA vaccine with the immunotherapy pembrolizumab led to a 49% reduction in the risk of cancer recurrence or death, and a 59% reduction in the risk of distant spread or death compared to the immunotherapy alone.

UI Health Care participated in the stage 3 clinical trial led by Mohammed Milhem, MBBS, medical oncologist at UI Health Care Holden Comprehensive Cancer Center. 

"This is a new way to attack cancer, and I am sure it will reverberate throughout all of oncology as a potential path for prevention of cancer,” Milhem says. “Other trials are ongoing to test this approach for lung, bladder, and kidney cancer, too. If those trials prove successful as well, then the landscape for how we approach cancer is about to take a huge turn.”

Read on for more details about the therapy.

Original story

From February 28, 2024

University of Iowa Health Care is among the first sites in the country to participate in a phase 3 clinical trial to test a new, personalized vaccine for patients with high-risk melanoma.

The study will combine individualized mRNA vaccines with the immunotherapy pembrolizumab to determine if the combination is safe and does a better job than pembrolizumab alone at preventing melanoma from returning in people with high-risk disease.

The first mRNA vaccines debuted in 2020 against COVID-19, but cancer researchers have also been studying how mRNA vaccines can be used to direct patients’ own immune systems to detect and target cancer cells. 

A personalized vaccine tailored for each patient 

A key feature of the new vaccines, developed by Moderna and Merck, is that they are tailored to target each patient’s unique tumor. The patient’s tumor is removed and sequenced, and the genetic information is used to create a personalized vaccine that can target multiple patient- and tumor-specific proteins. This individualized vaccine will prompt the patient’s own immune system to target tumor cells wherever they are in the patient's body.

We are excited to be participating in this international clinical trial, which allows us to offer this innovative, personalized cancer vaccine to Iowa patients with advanced melanoma - Mohammed Milhem, MBBS

The researchers hope the combination of the personalized vaccine with the pembrolizumab, which boosts the patient’s immune response, will prevent melanoma from returning.

“We are excited to be participating in this international clinical trial, which allows us to offer this innovative, personalized cancer vaccine to Iowa patients with advanced melanoma,” says Mohammed Milhem, MBBS, director of the Division of Hematology, Oncology, and Blood and Marrow Transplantation with UI Health Care, and the principal investigator for the UI site of the study.

Leadership in clinical trials for cancer vaccines 

Across all its global sites, the new trial aims to enroll 1089 patients with stage IIB to IV melanoma who will have their tumor surgically removed.

“We were selected as a U.S. site for the trial based on our national research leadership in melanoma and cancer vaccines and our expertise in conducting successful clinical trials,” says Milhem, who is also director of the Melanoma Program at Holden Comprehensive Cancer Center.

Patients will receive up to nine doses of the individualized vaccine given along with pembrolizumab. The vaccine is reported to have minimal side effects, including mild aches, chills, and mild fever.