Cancer immunotherapy

Immunotherapy is a very active area of cancer research. Many scientists and doctors around the world are studying new ways to use immunotherapy to treat cancer. Some of these are discussed here.

Treatments that target immune system checkpoints

The immune system has checkpoint proteins (such as PD-1 and CTLA-4) that help keep it from attacking other normal cells in the body. Cancer cells sometimes take advantage of these checkpoints to avoid being attacked by the immune system. Targeting these checkpoints is quickly becoming an important part of the treatment for some cancers, such as melanoma and non-small cell lung cancer. Researchers have also found promising early results against a number of other cancer types. Unlike most other cancer drugs, these checkpoint inhibitors seem to be helpful against many different types of cancer. Only a few of these treatments have been approved for use so far, but many others are now being studied in clinical trials.

A newer approach being studied is to combine treatments that have different targets (such as nivolumab, which targets PD-1, and ipilimumab, which targets CTLA-4) to see if this might work better. In melanoma, this combined approach has been shown to work better than using either treatment alone, but the combination also comes with an increased risk of serious side effects. Other studies are looking at combining checkpoint inhibitors with other types of drugs used to treat cancer.

Newer cancer vaccines

Vaccines are not yet a major type of treatment for cancer. Researchers have been trying to develop vaccines to fight cancer for decades, but this has proven to be harder than was first thought. As researchers have learned over the years, the immune system is very complex. It has also become clear that cancer cells have different ways of eluding the immune system, which makes creating effective vaccines difficult.

Researchers are using the knowledge gained in recent years to improve how they develop cancer vaccines. For example, vaccines are now often given along with other substances (called adjuvants) that help boost the body’s immune response, which might help the vaccines work better. Researchers are also studying the best way to give vaccines, looking to see if they work better when used alone or with other types of cancer treatments.

Types of cancer vaccines

Many different types of vaccines are now being studied to treat a variety of cancers.

Tumor cell vaccines

These vaccines are made from actual cancer cells that have been removed from the patient during surgery. The cells are altered (and killed) in the lab to make them more likely to be attacked by the immune system and then injected back into the patient. The patient’s immune system then attacks these cells and any similar cells still in the body.
Most tumor cell vaccines are autologous, meaning the vaccine is made from killed tumor cells taken from the same person in whom they will later be used. Other vaccines are allogeneic, meaning the cells for the vaccine come from someone other than the patient being treated. Allogeneic vaccines are easier to make than autologous vaccines, but it’s not yet clear if one type works better than the other.

Antigen vaccines

These vaccines boost the immune system by using only one antigen (or a few), rather than whole tumor cells. The antigens are usually proteins or pieces of proteins called peptides.
Antigen vaccines can be specific for a certain type of cancer, but they are not made for a specific patient like autologous tumor cell vaccines are.

Vector-based vaccines

These vaccines use special delivery systems (called vectors) to make them more effective. They aren’t really a separate category of vaccine; for example, there are vector-based antigen vaccines. Vectors are special viruses, bacteria, yeast cells, or other structures that can be used to get antigens into the body. The vectors are often germs that have been altered to make sure they can no longer cause disease.

Vectors can be helpful in making vaccines for a number of reasons. First, they can be used to deliver more than one cancer antigen at a time, which might make the body’s immune system more likely to mount a response. Second, vectors such as viruses and bacteria might trigger their own immune responses from the body, which could help make the overall immune response even stronger. Finally, these vaccines might be easier and less expensive to make than some other vaccines.

Some common cancers in which vaccines are being tested

Some of the more common types of cancer in which vaccines are now being studied include:

  • Brain tumors (especially glioblastoma)
  • Breast cancer
  • Cervical cancer
  • Colorectal cancer
  • Kidney cancer
  • Lung cancer
  • Lymphoma
  • Melanoma
  • Pancreas cancer
  • Prostate cancer

This is not a complete list – vaccines are being studied in other types of cancer as well.

The Advanced Skin Vaccination EPIMMUN™ with the P.L.E.A.S.E.® device is able to create much higher immune responses than with traditional injections. So there is a high possibility to reach the necessary therapeutic level to cure cancer.