A personalized cancer vaccine using messenger RNA technology is currently being tested in London, the first such vaccine to be tested on humans. Experts say this could be a “watershed moment” in the effort to permanently cure cancer, The Guardian reports.
Melanoma, the type of cancer for which this vaccine is being developed, affects around 132,000 people globally each year and is the most fatal skin cancer. Currently, surgery is the main form of treatment for the disease, but radiotherapy and chemotherapy are also sometimes used.
But experts are now testing personalized vaccines for each patient – once injected, the serum gives the body instructions on how to ‘hunt’ cancer cells and stop them from spreading rapidly. With the help of the vaccine, it would be possible for the body to become “immune” to cancer.
In the second phase of testing, doctors noticed that the vaccine drastically reduced the risk of cancer returning in melanoma patients. The third phase of testing has now begun, and the effort is being led by University College London.
Dr. Heather Shaw, the physician who is coordinating the national trial, said the vaccines have the potential to cure melanoma patients and are also being tested for other types of cancer, including lung, bladder and kidney.
Encouraging data
“It’s one of the most extraordinary things I’ve done in recent years. It’s an extremely well-made tool,” she said. The vaccine is a form of individualized therapy, made specifically for each individual patient. It is developed to produce an immune response in the patient’s body specific to the type of cancer and tumor.
mRNA-4157 instructs the body to activate an immune response that specifically targets mutations in the patient’s cancer. To customize it, doctors take a sample of the patient’s cancer during surgery, sequence it genetically using artificial intelligence, and then produce the vaccine.
“This is very similar to individualized therapy and is much smarter, in some ways, than a vaccine. The treatment is personalized for the patient – you can’t give it to the next patient because you don’t expect it to work,” said Shaw.
According to phase 2 data published in December, people with severe melanoma who were vaccinated, given the serum at the same time as MSD’s cancer drug Keytruda, had a nearly half (49%) reduced risk of death or cancer coming back after three years, compared to people treated only with the anticancer drug.
Patients were injected with one milligram of mRNA vaccine every three weeks for up to nine doses and 200 milligrams of Keytruda every three weeks (up to 18 doses) for about a year.
The international phase 3 study includes a wider range of patients and hopes to recruit around 1,100 people. These will include 60-70 patients from eight centers across the UK, including London, Manchester, Edinburgh and Leeds. According to Shaw, side effects include fatigue and pain in the area of the arm where the injection was made.
Professor Lawrence Young, from the University of Warwick, said “this is one of the most exciting developments in modern cancer therapy”, adding that “interest in cancer vaccines has been rekindled in recent years by a deeper understanding of how in which the body controls immune responses and through the emergence of mRNA vaccines”.
Editor: Adrian Dumitru
