Vaccines are a type of immunotherapy. Unlike vaccines to protect us from disease, cancer treatment vaccines are for people who already have cancer. Cancer vaccines help your body’s immune system recognise and attack cancer cells.
Research in this area is at an early stage. So vaccines are mainly available as part of clinical trials.
What are vaccines?
Normally, vaccines help to protect us from disease. They are made from weakened or harmless versions of the disease they are designed to protect us from. This means that they don’t cause the disease.
When you have a vaccine, it stimulates your immune system into action. The immune system makes antibodies that can recognise and attack the harmless versions of the disease. Once the body has made these antibodies it can recognise the disease if you come into contact with it again. So you’re protected from it.
What are vaccines to treat cancer?
Researchers are looking at vaccines as a possible treatment for cancer.
In the same way that vaccines work against diseases, the vaccines are made to recognise proteins that are on particular cancer cells.
An antigen is a substance that triggers the immune system to respond against it. For example, a virus has antigens on its surface which triggers the immune system to attack it. Body cells and cancer cells also have antigens on them.
Tumour associated antigens are proteins found in cancer cells. Normal cells either don’t have these antigens, or if they do, they have a much smaller amount.
Cancer treatment vaccines aim to help your immune system recognise these antigens. And to attack and destroy the cancer cells that have them.
Types of cancer vaccines
Scientists are studying many different types of cancer vaccines and how they work in different ways. More research is needed before they have a full picture of how well this type of treatment works and which cancers it could treat.
The following types of cancer vaccines are most commonly under investigation throughout the world:
Protein or peptide vaccines
These vaccines are made from special proteins in cancer cells. Or from small pieces of protein (peptides). They aim to stimulate your immune system to attack the cancer. Scientists have worked out the genetic codes of many cancer cell proteins, so they can make them in the lab in large quantities.
DNA and RNA vaccines
These vaccines are made with bits of DNA or RNA that are usually found in cancer cells. They can be injected into the body to make the cells of the immune system better at responding to and destroying cancer cells.
Whole cell vaccines
A whole cell vaccine uses the whole cancer cell, not just a specific cell antigen, to make the vaccine. The cancer cells are changed in the lab to make them easier for the immune system to find.
Scientists make the vaccine from your own cancer cells, another person’s cancer cells or cancer cells that were grown in the laboratory.
Dendritic cell vaccines
Dendritic cells help the immune system recognise and attack abnormal cells, such as cancer cells. To make the vaccine, scientists grow dendritic cells alongside cancer cells in the lab. The vaccine then stimulates your immune system to attack the cancer.
Scientists can change viruses in the laboratory and use them as a type of carrier to deliver cancer antigens into your body. They change the viruses so that they cannot cause serious disease. The altered virus is called a viral vector.
Some vaccines use a viral vector to deliver cancer antigens into your body. Your immune system responds to the viral vector. And this then helps your immune system to recognise and respond to the cancer antigen.
A treatment called T-VEC (talimogene laherparepvec), also known as Imlygic, is similar to virus vaccines. It uses a strain of the cold sore virus (herpes simplex virus). The virus has been changed by altering the genes that tell the virus how to behave. It tells the virus to destroy the cancer cells and ignore the healthy cells. This process also seems to help the immune system find and destroy other cancer cells.
T-VEC is now available as a treatment for some people with melanoma skin cancer whose cancer cannot be removed with surgery. It is also being looked at in trials for head and neck cancer. You have T-VEC as an injection directly into the melanoma or head and neck cancer.
When you might have these drugs
Research in this area is at an early stage. So cancer treatment vaccines are mainly available as part of clinical trials.
Ask your doctor if they know about any trials that might be suitable for you. This depends on many factors including:
- your type of cancer
- the stage of your cancer
- whether you have already had certain treatments
How you have treatment
You usually have these drugs as an injection under the skin (subcutaneous injection) or into muscle (intramuscular injection).
Many cancer treatment vaccines are new treatments. So there might be side effects we don’t yet know about.
Side effects we do know about are similar to other vaccines used for infectious disease. These include:
- redness, swelling, mild pain or itching where you have the injection
- flu like sumptoms such as feeling unwell or a high temperature (fever) for a few days after
Your doctor or trial team will tell you more about the individual side effects of each cancer vaccine. You can also read about side effects of individual vaccines in our trial summaries on the clinical trials database.