A UK man has become one of the first to receive an experimental mRNA vaccine designed to prevent recurrence of melanoma skin cancer. Steve Young, a 52-year-old musician, had a stage II melanoma removed previously, and said the shot is his “best chance” at stopping the cancer coming back.

“I feel lucky to be part of this clinical trial,” Young said in a statement. This is Phase 3 of a trial process that has already seen encouraging results in human volunteers, and Young will be joining just over 1,000 other people worldwide who will be taking part.

The vaccine is called mRNA-4157, or sometimes V940. It’s designed to be given alongside the drug Keytruda (pembrolizumab), and results from the earlier portion of the trial showed this combo led to a 44 percent reduction in recurrence or death at 18 months following surgical removal of high-grade melanoma.

Young and the other trial participants know that they’ll be receiving Keytruda. What will remain a mystery, both to them and the medics supervising them, is whether they’re getting the real vaccine or a placebo.

mRNA vaccines have been in the spotlight in recent years thanks to COVID-19. In fact, Moderna – architects of one of the shots that helped bring the pandemic under control – are also behind this skin cancer vaccine, in collaboration with another pharma company, MSD.

These types of vaccines work by providing the body’s cells with a set of blueprints so that they can get to work making specific proteins. For COVID, these are viral proteins that the immune system can recognize and respond to. In the case of mRNA-4137, the instructions tell the body how to make up to 34 different proteins only found on cancer cells, called neoantigens.

What makes this so exciting is that the suite of proteins can be personalized for each patient. The vaccine primes the patient’s immune system against proteins that are known to play a part in their specific cancer, while Keytruda tackles another of the cancer’s defenses in a two-pronged approach.

A lot of the lessons learned during the race to develop vaccines against COVID-19 are now having a renaissance in cancer vaccine research. Iain Foulkes, Executive Director of Research and Innovation at Cancer Research UK, wrote in an opinion piece that while this news is certainly exciting, “we can’t lose sight of the complex challenges ahead,” and vaccines are not going to be the one-and-only solution to cancer treatment.

But they’re already playing their part in different ways. The HPV vaccine program has had stunning success against cervical cancer, and early research is underway for vaccines against breast cancer and glioblastoma, to name a couple. 

Melanoma is not the most common type of skin cancer, but according to the American Association for Cancer Research, it results in the most deaths. Rates are on the up, so better treatments are more urgently needed than ever. Many people, clinicians and patients alike, will be watching the progress of this latest trial with great interest.