With the recent FDA approval of immunotherapy drugs, immunotherapy as a whole has been generating massive buzz (and hope) amongst the global cancer community and patients alike.
As a relatively new field of treatment however, immunotherapy raises a lot of questions. To answer those questions, in the last article we spoke about what immunotherapy exactly is and how it works.
Today, we’re looking at the different types of viable immunotherapy treatment methods.
So without further ado, here are the 5 main types of immunotherapy treatments that have been clinically approved:
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Monoclonal Antibodies
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Adoptive T-cell Therapy
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Checkpoint Inhibitors
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Cancer Vaccines
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Cytokines
Ready? Let’s go.
1. Monoclonal Antibodies (or mAbs)
Approved for a wide range of cancers, monoclonal antibodies are types of proteins designed specifically to detect cancer cells that mask themselves. These proteins or antibodies attach themselves to specific antigens found only on cancer cells.
By attaching to cancer cells, these antibodies essentially ‘mark’ them. Our immune system then recognizes these cancer cells which in turn initiates an attack on them.
Another type of mAb is the bispecific antibody. These not only mark the cancerous cells but also work to bring cancer-fighting T cells to the affected site.
Monoclonal antibodies are currently used for leukemia, breast, kidney, gastric, ovarian, cervical and brain cancer.
2. Adoptive T-cell therapy
Adoptive T-cell therapy leverages our T-cells which are a part of our immune cells that fight against foreign cells like cancer. T-cell therapies boost our immune system by either increasing the fighting ability or the number of immune T cells.
As a known fact, cancer cells particularly go unnoticed because of their shear number.
With adoptive CAR T-cell therapy:
i) The patient’s T cells are collected from the affected area
ii) These cells are then modified and activated to produce receptors on the surface of these cancer cells called CARs. These CARs or chimeric antigen receptors attach to the surface of cancer cells which helps detect them
iii) These activated T-cells are also multiplied before injecting them back into the patient’s body
iv) Once injected, these CAR T-cells start detecting and destroying the cancer cells
3. Checkpoint Inhibitors
It’s a known fact that our immune system puts checks on itself to make sure that it doesn’t over or under perform. To not over perform in particular, we have what are called checkpoint inhibitors.
Normally, we have proteins called PD-L1 present on the surface of ‘healthy’ cells. These proteins help our immune cells identify healthy cells and stop themselves from overacting on them.
Cancer cells take advantage of this defence mechanism. By producing large amounts of PD-L1 on their own surface, cancer cells camouflage themselves as healthy cells to our immune system. In other words,
Here’s where checkpoint inhibitors come in.
Checkpoint inhibitors bind or react with the PD-L1 on cancer cells making them visible and open to attack for immune cells.
Recently approved checkpoint inhibitors:
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Pembrolizumab (Keytruda)
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Atezolizumab (Tecentriq)
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Avelumab (Bavencio)
4. Cancer Vaccines
Cancer vaccinations essentially supercharge our immune response to cancerous cells They are based on the same principle that other vaccines are wherein a small modified amount of the particular virus or disease is introduced into the patient to train it to recognize and fight the disease.
Given as injections or intravenous infusions, cancer vaccines are made up of dead cancer cells or proteins. They stimulate immune cells to recognize them as foreign and assign fighter B-cells that produce antibodies that deal with all the cells that replicate these vaccines.
Examples of cancer vaccines:
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Provenge for prostate cancer
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CIMAvax EGF and Vaxina for non-small cell lung cancer
5. Cytokines
Instead of attacking any cancerous activity specifically, cytokines boost the overall power of immune cells. Cytokines such as interleukins (ILs) and interferons (IFNs) jumpstart the ability of immune cells to fight cancer.
ILs control the growth and activity of immune cells. IFNs on the other hand, trigger the production of proteins and white blood cells that help immune cells fight better.
Looking Ahead
Thanks to the promise shown by recently approved immunotherapy drugs, countless clinical trials and research breakthroughs, immunotherapy is already presenting countless treatment possibilities.
Even as a relatively new field, it is proving to be quite the weapon in the fight for a cancer-free future.
Take a moment to learn about the European Congress on Clinical Oncology where the global cancer community comes together to share their findings and discuss the latest breakthroughs, advances and challenges associated with cancer cure.