Cancer Vaccines Could Be Just Around The Corner – But They Need Investment

Vaccines aren’t just for infectious diseases. Any molecule that can be recognised by the immune system can be vaccinated against. The immune system is able to recognise cancer cells due to their high mutation rate, which causes them to express proteins not found elsewhere in the body. Because of this, it is possible to vaccinate against an ongoing cancer, essentially teaching the immune system to recognize and attack it more aggressively. 

There’s a major hurdle for cancer vaccines, though: not everyone’s cancer is the same. Mutation is inherently random, and while there may be some common denominators, one person’s lung cancer is going to contain a different range of mutations to another person’s lung cancer. This means that each person would need their own personalised vaccine developed specifically for them. Even then, a cancer will continue to mutate and acquire new mutations that reduce the immune system’s ability to detect them.

This is where gene therapy-based vaccines step in. Unlike traditional vaccines, which work by introducing the immune system to pieces of a pathogen for recognition, gene therapy vaccines deliver genetic material inside a virus or lipid nanoparticle. This genetic material then instructs specialised cells to make the desired proteins, which they will then present to the immune system for recognition. This means that once a working vaccine exists, different genetic material can simply be ‘plugged in’ to the delivery system as required. When combined with genetic sequencing, this would allow personalised vaccines to be developed very quickly.

In the case of cancer, a doctor would take a biopsy of a patient’s cancer and send it to the lab for genetic sequencing. A machine learning algorithm would then identify which genetic mutations within that cancer encode the most promising protein targets for the immune system. DNA or mRNA with instructions on how to make those proteins would then be manufactured and packaged into the vaccine delivery system to be given to the patient.

How close are we to such vaccines becoming a standard treatment? The FDA recently granted breakthrough therapy designation to a personalised skin cancer vaccine developed by Moderna, after a clinical trial suggesting that it cut risk of death or recurrence of melanoma by 44%. Dr Paul Burton, the chief medical officer of Moderna, believes the company may be able to offer similar treatments in as little as 5 years, and not just for cancer.

Personalised vaccines could be developed to prevent or treat other diseases such as heart disease and autoimmune diseases. The idea of vaccinating against an autoimmune disease might seem strange, given that autoimmune diseases are caused by the immune system reacting to the body’s own proteins. However, just as gene therapy can be used to activate an immune response, it can also be used to tell the immune system not to attack a specific protein.

Within a mere decade, we could rapidly identify the genetic characteristics of any disease for a specific person, then develop a personalised therapy using gene therapy and machine learning tools. This would change medicine as we know it, but can’t happen without investment. While investment in gene therapy-based vaccines has exploded, it arguably still doesn’t reflect the potential gains that this technology has to offer. We know from our experience with COVID-19 that effective vaccines can be developed very quickly if needed. Cancer alone kills 10 million people a year – higher than COVID’s toll since 2020. We also know that there will be another, deadlier pandemic sooner or later. Perhaps we should be pushing this vaccine technology with more urgency.