The new vaccine gives hope for the fight against melanoma already given to patients in Britain.

Doctors began testing hundreds of patients the first personalized vaccine against cancer mRNA in the world for melanoma, as experts hailed its “game-changing” potential to cure cancer permanently.

Melanoma strikes about 132,000 people a year worldwide and is the leading cause of skin cancer death. Currently, surgery is the main treatment, although sometimes radiation therapy, drugs and chemotherapy are also used.

Now the experts they are testing new vaccines that are tailor-made for each patient and tell his body to hunt cancer cells to prevent the disease from coming back.

A phase 2 trial found that the vaccines dramatically reduced the risk of cancer recurrence in melanoma patients. A definitive, phase 3, trial has now begun and is being led by University College London Hospitals NHS Foundation Trust (UCLH).

Dr. Heather Shaw, the national coordinating investigator for the trial, said the vaccines had the potential to treat people with melanoma and were being tested in other cancers, including lung, bladder and kidney.

The vaccine is a personalized neoantigen therapy. It is designed to activate the immune system, so that it can treat a patient’s specific type of cancer and tumor.

Known as mRNA-4157 (V940), the vaccine targets tumor neoantigens, which are expressed by tumors in a particular patient. These are markers on the tumor that can potentially be recognized by the immune system.

To personalize it, a tumor sample is removed during the patient’s surgery, followed by DNA sequencing and the use of artificial intelligence. The result is a custom-made anti-tumor graft that is specific to the patient’s tumor.

“This is very much a personalized treatment and it’s much smarter in some respects than a vaccine,” Shaw said. “It’s completely tailored to the patient – ​​you couldn’t just give it to the next patient down the line because you wouldn’t expect it to work.

“They may have some new antigens in common, but they’re likely to have their own very individual new antigens that are important to their tumor, and so it’s really individualized.”

The ultimate goal is to permanently cure patients of their cancer, Shaw said. “I think there’s real hope that these will be game changers in immunotherapy,” he said.

Phase 2 data found that people with high-risk melanomas who got the vaccine alongside Keytruda immunotherapy were nearly half (49%) as likely to have their cancer die or come back after three years than those who got Keytruda alone .

Patients received 1 mg of the mRNA vaccine every three weeks for a maximum of nine doses and 200 mg of Keytruda every three weeks (a maximum of 18 doses) for about a year.

One of the first patients in the trial at UCLH is Steve Young, 52, from Stevenage in Hertfordshire. “I’m really, really excited,” he said. “This is my best chance to stop cancer in its tracks.”