Dostarlimab: The Miracle Drug that has the Potential to Eradicate The 3rd Most Common Cancer
By Eva Fata
What if I said that there is a cure for colorectal cancer?
What if I told you that there were no side effects?
What if I told you that the cancer was 100% cured?
Well, it might not be a full-on cure, but it did cure 18 patients with no side effects. It's called Dostarlimab — a miracle cure. I’ll explain to you how Dostarlimab works and the results.
Dostarlimab is a drug which has a collection of lab molecules which can act as a replacement for human antibodies. It acts in a way which can allow your cells to attack the cancer cells and kill them.
A small group of colorectal patients (18 people), after this trial done by a doctor at the Memorial Sloan Kettering Cancer Centre, their disease subsided (100% cure)!?! The trial results have been labelled as “surprising” because every patient was cured completely without any exceptions!
Not only that, the patients had no side effects! This is amazing. A lot of treatments have side effects which can be non-life threatening but very unpleasant (nausea) but also life-threatening side effects (damage to organs, low blood cell counts).
Immunotherapy is a technology which we should continue to improve and research to get even better results like this one.
Background of colorectal cancer
The second leading cause of death by cancer type is colorectal cancer.
In 2020, there were 1,806,590 new cases of colorectal cancer.
Colorectal cancer is the third most common cancer worldwide.
Colorectal cancer happens when cells in the colon and rectum grow out of control. The colon is the longest and first part of the large intestine. The large intestine is the last part of the digestive system, which breaks down food for the body to use.
It typically affects people over the age of 50 but can appear at any age. The overall risk for colon cancer is 1 in 23 for men and 1 and 26 for women.
Colon cancer usually begins with small clumps of cells called polyps that form along the lining of the colon. Polyps are usually not cancerous, however, they can turn into colon cancer over time.
Polyps often don’t cause symptoms. Therefore, doctors recommend getting regular screenings to look for polyps in the colon, to find one and remove it before it becomes cancer, which helps prevent colon cancer.
Immunotherapy
Immunotherapy uses the body's immune system to fight cancer. Substances in which the body or made in a lab are used to boost, direct or restore the body's natural defences against cancer.
Immune checkpoint inhibitor therapy → Immune checkpoint inhibitors block proteins called checkpoints that are made by some types of immune system cells, such as T-cells and some cancer cells. These checkpoints can help keep immune responses from being too strong and also sometimes keep T cells from killing cancer cells. When these checkpoints are blocked, T cells can kill cancer cells better. These are used to treat some patients with metastatic colorectal cancer.
There are two types of immune checkpoint inhibitor therapy:
- CTLA-4 inhibitor therapy → CTLA-4 is a protein on the surface of T cells which helps keep the body’s immune responses in check. When CTLA-4 attaches to another protein called B7 on a cancer cell, it stops the T cell from killing the cancer cell. CTLA-4 inhibitors attach to CTLA-4 which allows the T cells to kill cancer cells.
- PD-1 and PD-L1 inhibitor therapy → PD-1 is a protein on the surface of T cells which helps keep the body’s immune responses in check. PD-L1 is a protein found on some types of cancer cells. When PD-1 attaches to PD-L1, it stops the T cell from killing the cancer cell. PD-1 and PD-L1 inhibitors keep PD-1 and PD-L1 proteins from attaching.
How Dostarlimab works
Dostarlimab is a drug which has a collection of lab molecules which can act as a replacement for human antibodies. Dostarlimab attaches to PD-1 which is found on the surface of T cells. PD-1 in healthy T cells acts as a brake which prevents the cells from starting an uncontrollable immune response.
However, PD-1 can also inactivate T cells in tumours and prevent them from destroying cancer cells. A cancer cell or normal cell within the tumour mass has an increased amount of PD-L1 and PD-L2 molecules on their surfaces which bind to PD-1. When these two molecules (PD-L1 and PD-L2) attach with the PD-1 receptor on the T cell, the T cell gets inactivated and cannot kill the cancer cells.
Dostarlimab binds to the PD-1 in a way which resists PD-L1 and PD-L2 from attaching to the PD-1 receptor. This blockage on PD-1 allows the T cells to activate and attack and kill the cancer cells.
Other ways to treat colorectal cancer
Surgery
Removing the cancer is the most common treatment for all stages of colorectal cancer. There are two types of surgery which a doctor may use to remove the cancer.
- Local excision → If the cancer is found at a very early stage, the doctor can remove it without cutting through the adnominal wall. Instead, the doctor will put a tube with a cutting tool through the rectum into the colon and cut the cancer out.
- Resection of the colon with anastomosis → If the cancer is larger, the doctor will perform a partial colectomy (removes the cancer and a small amount of healthy tissue around it). The doctor then may perform an anastomosis (sewing the healthy parts of the colon together). The doctor will also usually remove lymph nodes near the colon to see if they have cancer
After the doctor removes all the cancer that was seen, some patients may be given chemotherapy or radiation therapy to kill cancer cells which may be lurking in the body.
The downsides of surgery are the risk of bleeding and blood which can be threatening.
Chemotherapy
Chemotherapy uses drugs to stop the growth of cancer cells by either killing them or stopping them from dividing. Chemotherapy is taken by mouth or injected into a vein or muscle and then the drugs enter the bloodstream and can reach cancer cells.
The downside to chemotherapy is that it causes a lot of side effects during the treatment (e.g. hair loss, nausea) and also long-lasting side effects depending on the treatment (e.g. nerve damage, risk of second cancer).
Radiation therapy
Radiation therapy is a treatment which uses high-energy X-rays or other types of radiation to kill cancer cells or to stop them from growing. The two main types of radiation therapy are:
- External radiation therapy uses a machine outside the body to send radiation toward a specific area of the body with cancer
- Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wire or catheters that are placed directly or near the cancer.
Radiation therapy has downsides to it as well. Not only does it kill cancer cells, it also kills healthy cells. Some side effects from this are hair loss, fatigue and diarrhea.
Targeted therapy
Targeted therapy uses drugs or other substances to identify and attack specific cancer cells.
Some targeted therapies used for the treatment of colon cancer are:
Monoclonal antibodies → Monoclonal antibodies are immune system proteins that are made in the laboratory to treat many diseases including cancer. These antibodies can attach to a specific target on cancer cells or other cells which may help cancer cells grow. These antibodies are then able to kill the cancer cells and block their growth or keep them from spreading. Monoclonal antibodies are given by infusion and may be used alone or to carry drugs, toxins or radioactive material directly to cancer cells.
There are different types of monoclonal antibody therapy
- Vascular endothelial growth factor (VEGF) inhibitor therapy → Cancer cells make a substance called VEGF, which causes new blood vessels to form (angiogenesis) and helps cancer to grow. These VEGF inhibitors block VEGF and stop new blood vessels from forming. This may kill cancer cells because they need new blood vessels to grow.
- Epidermal growth factor receptor (EGFR) inhibitor therapy → EGFRs are proteins found on the surface of certain cells, including cancer cells. epidermal growth factor attaches to the EGFR on the surface of the cell and then causes the cells to grow and divide. The EGFR inhibitor blocks the receptor and stops the epidermal growth factor from attaching to the cancer cell. This then stops the cancer cell from growing and dividing.
- Angiogenesis inhibitors → Angiogenesis inhibitors stop the growth of new blood vessels which tumours need to grow.
- Ziv-aflibercept → a vascular endothelial growth factor trap which blocks an enzyme needed for the growth of new blood vessels in tumours.
- Regorafenib is a drug which is used to treat colorectal cancer which has spread to other parts of the body and not gotten better with other treatments. It blocks the action of certain proteins, like the vascular endothelial growth factor. This may keep cancer cells from growing and may even kill them! It can also prevent the growth of new blood vessels in which tumours need to grow.
- Protein kinase inhibitor therapy → A treatment which blocks a protein needed for cancer cells to divide. Protein kinase inhibitors include:
- BRAF inhibitors: block the activity of proteins made by mutant BRAF genes
The downside to targeted therapy is that: Some life-threatening side effects include: high blood pressure, heart damage, and bleeding and may interfere with blood vessel growth. It has some non-life-threatening side effects such as hair loss and nausea.
As you can see surgery, targeted therapy, chemotherapy and radiation therapy come with a lot of side effects and downsides to them. Another thing is a lot of these treatments don’t always work well and are not always successful.
This is where Dostarlimab is a star. Dostarlimab had ZERO side effects and was also 100% effective (100% cured). This is a win-win for Dostarlimab.
Now I understand that it was a small trial and still has some work to be done — of course, but we can build on the current results and keep researching and building it to possibly find a cure and/or treat other cancers with Dostarlimab.
Thank you for reading! If you have any questions please email me at efata968@gmail.com
Dedicated to Massimo
Sources:
https://cancer.ca/en/treatments/treatment-types/radiation-therapy/side-effects-of-radiation-therapy
https://www.ucir.org/immunotherapy-drugs/dostarlimab-gxly
https://my.clevelandclinic.org/health/treatments/11582-immunotherapy
https://www.wcrf.org/cancer-trends/worldwide-cancer-data/
https://www.mayoclinic.org/tests-procedures/chemotherapy/about/pac-20385033
