04:02 - Source: CNN
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New data from a trial of an investigational mRNA vaccine shows that it reduced the risk of recurrence of the serious skin cancer melanoma when combined with immunotherapy, according to drugmakers Moderna and Merck.

In a trial of 157 people who had had surgery to treat melanoma, 78.6% of those who received the personalized vaccine and the immunotherapy Keytruda were free of cancer at 18 months, while 62.2% of people who got only the immunotherapy were recurrence-free. Cancer recurrence or death happened in 22.4% – 24 out of 107 – who received the combination treatment and 40% – 20 out of 50 – who received only the immunotherapy.

No serious side effects from the experimental vaccine have been reported. The most common side effects were fatigue, injection site pain and chills.

Dr. Kyle Holen, Moderna’s senior vice president and head of development, therapeutics and oncology, said in a statement that the results “provide further encouragement for the potential of mRNA” for people with melanoma, and it “may be a novel means of potentially extending the lives of patients.”

Moderna’s experimental cancer vaccine, mRNA-4157/V940, is designed to prime the immune system to generate a response to specific tumors. Merck’s Keytruda, which is already used in the treatment of melanoma, stimulates the immune system to attack tumors.

Data from the Phase 2b trial has not been peer-review or published; preliminary results from the trial were shared in December. The companies presented the latest data at the American Association for Cancer Research’s annual meeting.

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The companies have said they plan to launch a Phase 3 study in 2023 and will expand to more types of tumors, including lung cancer.

According to the American Cancer Society, melanoma accounts for about 1% of all skin cancers, but it causes a majority of skin cancer deaths. The group estimates that in 2023, about 100,000 new melanomas will be diagnosed in the US, and almost 8,000 people will die from melanoma.