Moderna’s mRNA Vaccine Aims to Stop Cancer Spreading by Teaching the Immune System to Recognise Cancer Cells

US drug and vaccine maker Moderna has reported a new possibility in cancer treatment. The company is developing an mRNA-based vaccine that, it is hoped, could reduce the risk of cancer spreading from one organ of the body to another. The central idea behind the research is that the vaccine may activate the body’s own immune system against cancer.

One reason cancer becomes so dangerous is this very spread. Cancer does not always remain confined to a single organ; it can move from one organ to another. In medical science this process is called ‘metastasis’, and it plays a major role in the disease turning fatal.

If detected at an early stage, cancer can in many cases be controlled or cured through treatment. But once the disease reaches the third or fourth stage, treatment becomes complicated and the risk to the patient rises many times over. Doctors use various tests to determine whether the cancer has spread to other parts of the body.

Cancer cells can break away from the original tumour, travel to another part of the body and form a new tumour there. Several routes work behind this spread, the most familiar of which is the bloodstream.

In spread through the blood, cancer cells enter the blood vessels and travel with the blood to other parts of the body. Finding a favourable environment there, the cells start growing again and give rise to new tumours.

The second route is the lymphatic system. Cancer cells can also reach different parts of the body through the lymph channels. In this way there is a risk of cancer spreading to the lungs, liver, brain or bones, making treatment even harder.

Beyond this, cancer cells can invade the healthy tissue surrounding the original tumour and grow there. From there, a path opens for the disease to spread further through the body. Through any one of these three routes, the disease can gradually take hold of the whole body.

Moderna’s vaccine is built on mRNA technology. Such a vaccine gives the body’s immune system a kind of instruction to build a response against a specific target — in other words, the immune system learns which cells it needs to attack.

One of the vaccine’s main aims is to activate the immune system by targeting certain special proteins in cancer cells, known as ‘neoantigens’. Neoantigens are special antigens created by genetic changes in cancer cells; if immune cells can identify them, they can single out and attack the cancer cells.

Alongside the hope, however, a note of caution has been sounded clearly. It is by no means certain that the vaccine will directly destroy the proteins of all cancer cells or completely stop cancer from spreading. Its effectiveness will depend on the results of clinical trials and on which type of cancer it is applied to.

Reports mention a third-phase trial of the vaccine. But without updated information on the trial’s current status, the approval process and a possible timeline for reaching the market, it cannot be said with certainty that it will reach ordinary patients any time soon.

All in all, while this mRNA research opens a door of new possibility in cancer treatment, more scientific data and trial results will be needed to confirm how effective and safe the vaccine is. Only when those results are in hand will it be clear how big a weapon this vaccine can become in the fight against cancer.