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Many of us have loved ones who have gone through treatment for cancer, and for those whose treatment has been successful, many owe their lives to chemotherapy. Chemotherapy was identified as a potential treatment for cancer, not in a lab, as you might expect. Its origins lie far from the sterile environment of a hospital, as it originated in the battlefields of World War One. In this blog, we look at the development of chemotherapy drugs and their trials to give you an overview of how this type of treatment came to pass.
Was chemotherapy discovered by accident?
During the course of WW1, many soldiers suffered the devastating effects of a chemical weapon known as mustard gas. Causing lung damage, blistering and degradation of white blood cells, it was a horrific experience for those exposed to it. However, some scientists were curious as to whether it could be used for good. They wondered if the chemical could kill off cancer cells without damaging healthy ones.
It was during World War II that scientists made a fascinating and hopeful discovery. Researchers were studying nitrogen mustard and confirmed that the compound could shrink tumours in mice. This led scientists to hypothesise that the compound could be used to target the devastating condition of lymphoma. The first clinical trials began with promising results. Tumours shrank, and some patients went into remission.
A combination of projects
Around the same time, another discovery was made that would impact the development of chemotherapy. At Boston Children’s Hospital, Sidney Farber investigated folic acid and how it could inhibit the growth of cancer cells. His research led to the development of aminopterin. This drug was found to treat acute lymphocytic leukaemia (ALL), sending patients into remission. Aminopterin’s success was then followed by the development of methotrexate, a chemotherapy drug that targets the cellular processes in the body, effectively combatting cancer.
More drugs developed
Following the success of these early discoveries, other chemotherapy drugs were developed, which allowed physicians to tailor treatments to:
- Damage DNA to prevent cancer cells from replicating
- Interfere with DNA synthesis to stop cell division
- Inhibit cell division, preventing the multiplication of cancer cells
- Block hormone activity that leads to the growth of cells
Testing new formulations
Chemotherapy drug trials were less sophisticated than they are today. Typically, they were not fully resourced, and there needed to be more standardised protocols. However, as with many areas of science, clinical trials have become more sophisticated. Specific advancements in the field included:
- Randomised control trials are where patients are randomly assigned to whether they receive the treatment or a placebo.
- Blinding, in which the doctor, patient, or both are unaware of how the assignment is made, can minimise bias.
- Phased trials, in which specific questions are identified for each phase, are related to optimal dosing, safety, and effectiveness.
- Combination therapy is used to avoid drug resistance. As cancer cells can develop resistance to a single drug, using multiple drugs can increase the effectiveness of treatment.
The story continues
Of course, there are still significant challenges with chemotherapy. These include the well-known and documented side effects, drug resistance, and the potential for treatments to harm healthy cells. Clinical trials are ongoing to try and reduce the symptoms of sufferers on chemotherapy and to improve the anti-resistance of cancer drugs.
Obviously, there is a long way to go before we can say we have a cure for cancer if we ever will. However, using optimised chemotherapy trial techniques, and an ever-growing knowledge of how cancer cells evolve, the future for many patients with cancer looks a little brighter than before.
You may also like: Navigating The Changing Landscape Of Clinical Trials
Photo by National Cancer Institute on Unsplash