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Moderna and Merck are studying an mRNA vaccine in combination with immunotherapy in melanoma patients.
CNN –
An investigational mRNA vaccine used alongside immunotherapy continues to show benefits for people with high-risk forms of the skin cancer melanoma, drugmakers said Thursday.
In a three-year follow-up of study participants who had stage III or IV melanoma completely removed but were at high risk of the cancer coming back, those who received Moderna's vaccine along with Merck's Keytruda immunotherapy had , a 49% lower rate of recurrence or death and a 62% lower risk of distant tumor cell spread or death compared to those who received Keytruda alone, the companies said in a news release.
At a two-year follow-up, people who received Keytruda and the mRNA-4157/V940 vaccine had a 44% lower risk of recurrence or death and a 65% lower risk of distant metastasis or death who received the Keytruda vaccine alone.
About a quarter of study participants who received Keytruda plus the vaccine reported serious adverse events related to treatment, compared with about 20% of those who received Keytruda alone. The most common side effects attributed to the vaccine were fatigue, pain at the injection site and chills.
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The U.S. Food and Drug Administration first approved Keytruda, which boosts the immune system's ability to recognize and fight cancer cells, in 2014 for the treatment of certain types of cancer. The agency granted breakthrough therapy designation to mRNA-4157/V940 in combination with Keytruda, which accelerates the development and review of drugs to treat a serious disease and that preliminary clinical evidence indicates is a significant improvement over available therapies can represent.
The data from the Phase 2b trial of the therapies has not been peer-reviewed or published in a peer-reviewed journal. Moderna and Merck say they have begun Phase 3 trials in stage IIB-IV melanoma and non-small cell lung cancer and plan to expand the research to additional tumor types.
According to the American Cancer Society, melanoma accounts for about 1% of all skin cancers but causes the majority of skin cancer deaths. The group estimated that about 100,000 new melanomas would be diagnosed in the U.S. in 2023 and nearly 8,000 people would die from melanoma.
CNN's Jamie Gumbrecht contributed to this report.