Doctors have started testing the world’s first personalized mRNA cancer vaccine for melanoma in hundreds of patients, as experts hailed its ‘game-changing’ potential to permanently cure cancer.
Melanoma affects approximately 132,000 people worldwide each year and is the leading cause of death from skin cancer. Currently, surgery is the main treatment, although radiotherapy, medications and chemotherapy are also sometimes used.
Now experts are testing new jabs tailored to each patient that tell their bodies to detect cancer cells to prevent the disease from ever coming back.
A phase 2 trial found that the vaccines dramatically reduced the risk of cancer recurrence in melanoma patients. Now a final phase 3 trial has been launched, led by University College London Hospitals NHS Foundation Trust (UCLH).
Dr. Heather Shaw, the study’s national coordinating investigator, said the jabs had the potential to cure people with melanoma and were being tested in other cancers including lung, bladder and kidney cancer.
“This is one of the most exciting things we’ve seen in a very long time,” Shaw said. “This is a very finely honed instrument. To be able to sit there and say to your patients that you’re offering them something that’s basically like the Fat Duck at Bray versus McDonald’s – it’s that level of cordon bleu coming to them… The patients are very excited about them.
The vaccine is an individualized neoantigen therapy. It is designed to activate the immune system so it can fight back against a patient’s specific type of cancer and tumor.
The vaccine is known as mRNA-4157 (V940) and targets tumor neoantigens, which are expressed by tumors in a given patient. These are markers on the tumor that may be recognized by the immune system.
The shot encodes up to 34 neoantigens and activates an anti-tumor immune response based on the unique mutations in a patient’s cancer.
To personalize it, a tumor sample is removed from the patient during surgery, followed by DNA sequencing and the use of artificial intelligence. The result is a tailor-made anti-cancer shot that is specific to the patient’s tumor.
“This is very much an individualized therapy and in some ways is much smarter than a vaccine,” Shaw said. “It is absolutely tailor-made for the patient. You couldn’t give this to the next patient in line because you wouldn’t expect it to work.
“They may have some shared novel antigens, but they probably have their own, very individual novel antigens that are important to their tumor and that’s why it’s really personalized.”
The ultimate goal is to permanently cure patients of their cancer, Shaw said. “I think there is real hope that these will be game changers in immunotherapy,” she said.
Phase 2 data showed that people with severe high-risk melanoma who received the jab in addition to the Keytruda immunotherapy were almost half (49%) more likely to die or have their cancer come back after three years than those who received Keytruda alone.
Patients received 1 mg of the mRNA vaccine every three weeks for up to nine doses, and 200 mg of Keytruda every three weeks (up to 18 doses) for about a year.
The global Phase 3 trial will now include a wider range of patients and aims to recruit around 1,100 people. The UK arm aims to recruit at least 60 to 70 patients across eight centres, including London, Manchester, Edinburgh and Leeds.
One of the first patients to take part in the trial at UCLH is Steve Young, 52, from Stevenage in Hertfordshire. “I’m really excited,” he said. “This is my best chance to stop the cancer.”