CAR T-CELL THERAPY

1. Context

2. What is CAR T- Cell therapy?

3. What are CAR T-Cells?

• Chimeric antigen receptor (CAR) T-­cell therapies represent a quantum leap in the sophistication of cancer treatment. Unlike chemotherapy or immunotherapy, which require mass­produced injectable or oral medication, CAR T­-cell therapies use a patient’s own cells.
•  They are modified in the laboratory to activate T-­cells, a component of immune cells, to attack tumors. These modified cells are then infused back into the patient’s bloodstream after conditioning them to multiply more effectively.
• The cells are even more specific than targeted agents and directly activate the patient’s immune system against cancer, making the treatment more clinically effective. This is why they’re called ‘living drugs’.

4. How does it work?

• The therapy targets leukaemia and lymphoma. Leukaemia is a cancer of blood-forming tissues, including bone marrow. Lymphoma is a cancer of the lymphatic system, which is part of the body's germ-fighting network.
• It uses lentiviral technology. In gene therapy, this is a method of inserting, modifying or deleting genes in organisms using lentivirus, a family of viruses responsible for diseases such as AIDS (acquired immunodeficiency syndrome).
• As a part of the treatment, a specific type of white blood cells and T cells are changed in the lab so they can find and destroy cancer cells.
• It is also sometimes referred to as a type of cell-based gene therapy because it involves altering genes inside T cells to help them attack cancerous cells.

5. How has systemic therapy evolved?

• Systemic therapy’s earliest form was chemotherapy; when administered, it preferentially acts on cancer cells because of the latter’s rapid, unregulated growth and poor healing mechanisms.
• Chemotherapeutic drugs have modest response rates and significant side­ effects as they affect numerous cell types in the body.
• The next stage in its evolution was targeted agents, also known as immunotherapy. Here the drugs bind to specific targets on cancer or on the immune cells that help the tumour grow or spread.
• This method often has fewer side­ effects as the impact on non ­tumour cells is limited. However, it is effective only against tumours that express these targets.

6. Will it be an expensive treatment in India?

• In India, introducing any new therapy faces the twin challenges of cost and value.
• Critics argue that developing facilities in India may be redundant and/or inappropriate as even when it becomes cheaper, CAR T­-cell therapy will be unaffordable to most Indians.
• Those who are affluent and require the therapy currently receive it abroad anyway.
• While this is true, it may be the right answer to the wrong question. Having access to a global standard of care is every patient’s right; how it can be made more affordable can be the next step.
• Investments in developing these technologies in India represent the hope that, as with other initially expensive treatments like robotic surgery, we will be able to provide economies of scale.
• The sheer volume of patients in India has the potential to drive the cost of treatment down.

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