Cancer, a major global health issue, can be treated with surgery, radiotherapy, or systemic therapy. Over the years, improvements in these methods have been made, but the most significant developments have been in systemic therapy. Chimeric antigen receptor (CAR) T-cell therapy, a recent breakthrough in this area, is receiving worldwide recognition.
Major Interventions in Systemic Therapy for Cancer Treatment
The first form of systemic therapy was chemotherapy, which combated cancer by targeting its rapidly growing cells. However, the effectiveness of chemotherapy drugs was limited and they came with serious side effects because they affect many types of cells in the body, not just the cancerous ones.
Immunotherapy, also known as targeted agents, marked the next advancement in systemic therapy. These targeted agents work by binding to specific targets on the cancer or immune cells, which reduces the toxic impact on non-tumor cells. However, this method is only effective against tumors with these specific targets.
Understanding CAR T-cell Therapy
CAR T-cell therapies are a significant advance in cancer treatment. Unlike traditional treatment methods that involve drug intake, CAR T-cell therapies utilize the patient’s own cells. These cells are modified in a lab to activate T-cells which then target tumor cells. The therapy is currently approved for treating leukaemias and lymphomas.
In the treatment procedure, T cells are extracted from the patient’s blood and a gene for a special receptor, called a chimeric antigen receptor (CAR), that binds to a certain protein on the patient’s cancer cells is added. These CAR T cells are then proliferated in large amounts in a lab and infused back into the patient.
The Significance and Challenges of CAR T-cell Therapy
CAR T-cell therapies provide a more targeted approach than previous treatments and directly stimulate the patient’s immune system to fight cancer, resulting in higher clinical efficacy. For this reason, they are often referred to as “living drugs”.
However, the complexities of preparing CAR T-cell therapies have hindered their widespread use. The first successful clinical trial was reported a decade ago, while the first indigenously developed therapy in India was performed only in 2021. In addition, while certain types of leukaemias and lymphomas have a high success rate of about 90%, the success rate for other cancers is lower. Potential side effects, including cytokine release syndrome and neurological symptoms, have also been noted.
Lastly, cost is also a major concern. Critics argue that even developing CAR T-cell therapy within India may not be cost-effective since it would still be unaffordable for most people.
Role of T Cells in Immunity
T cells, a type of white blood cell, play a key role in immune response. They help the body recognize and respond to foreign substances like viruses, bacteria, and abnormal cells, including cancer cells. There are two major types of T cells: helper T cells, which support other cells of the immune system, and cytotoxic T cells, which annihilate virally infected cells and tumors.
Government Initiatives in Cancer Treatment
Several initiatives have been launched by the government to combat cancer. These include the National Programme for Prevention and Control of Cancer, Diabetes, Cardiovascular Diseases and Stroke; the National Cancer Grid; and National Cancer Awareness Day. Such initiatives aim to raise awareness, prevent, and control cancer across the nation.
