Personalised Skin Cancer Vaccine Shows Promising Results in Clinical Trials

The results of the clinical trial for the skin cancer vaccine, Intismeran, a collaboration between Moderna and Merck, have been published, showcasing astonishing results. The vaccine is primarily designed to reduce the risk of death among skin cancer patients who have had their tumor removed through surgery, with hopes that it may be applicable to other tumors such as kidney, bladder and lung cancers.

Two years after the initial treatment, the results of the most recent clinical trial have shown that patients who used the cancer vaccine, Intismeran, alongside Keytruda — a widely used immunotherapy drug — reduced the risk of either death or cancer recurrence by 42%. The combination of drugs also reduced the risk of melanoma, a form of skin cancer, from spreading by 38% over two years compared to immunotherapy alone.

Intismeran is a mRNA vaccine, which means that it is largely personalized to each individual cancer patient. A patient first undergoes a biopsy, and their removed cancer cells are compared to their healthy cells to see what the differences are. The mRNA platform then takes the top 34 differences in the cells to code what is known as the “neoantigen”— a sequence of tumor-specific proteins — which is then injected into the patient. The vaccine then trains the immune system to recognize and target these neoantigens, in a similar manner as to how standard vaccines recognize and target a common virus or bacteria.

In the case that the cancer does return, the hope is that with the vaccine, the patient’s immune system will recognize these cancer cells and target them.

While this is a hallmark achievement in terms of cancer treatment, there are still several hurdles that need to be crossed before the drug is officially rolled out.

1. There needs to be more longitudinal research conducted on the current patients enrolled in the clinical trial. Previous attempts at combining Keytruda with other drugs have resulted in worse side effects, as well as failing to improve cancer recurrence rates.
2. Cost remains an issue of concern, as each vaccine needs to be personalized for the individual with genetic analysis conducted on their tumor. Governments will need to consider funding availability when determining the scale of distribution for the drug.
3. The drug needs to undergo a regulatory review process which could take several years, and publication of the drug in peer-reviewed medical journals is also necessary so that it can be examined by independent experts.