NEXCAR19 – SCI & TECH

News: UPSC Essentials | One word a day — NexCAR19, the therapy

 

What's in the news?

       The Central Drugs Standard Control Organisation (CDSCO) this month granted market authorisation for NexCAR19.

       It is India’s first indigenously-developed CAR-T cell therapy, to ImmunoACT, a company incubated by IIT Bombay.

 

NexCAR19 Therapy:

       NexCAR19 therapy is designed to target cancer cells that carry the CD19 protein. This protein acts like a flag on cancer cells, which allows CAR-T cells to recognise and attach themselves to the cancer cells and start the process of elimination.

       India is now one of the first developing countries to have its indigenous CAR-T and gene therapy platform.

       The therapy is for people with B-cell lymphomas who didn’t respond to standard treatments like chemotherapy, leading to relapse or recurrence of the cancer.

 

Go back to basics:

CAR T-cell Therapy:

       Chimeric antigen receptor (CAR) T-cell therapies represent a quantum leap in the sophistication of cancer treatment.

       Unlike chemotherapy or immunotherapy, which require mass-produced 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 tumours.

       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’.

 

How does it work?

       In CAR T-cell therapy, the patient’s blood is drawn to harvest T-cells – immune cells that play a major role in destroying tumour cells.

       Researchers modify these cells in the laboratory so that they express specific proteins on their surface, known as chimeric antigen receptors (CAR) - they have an affinity for proteins on the surface of tumour cells.

       This modification in the cellular structure allows CAR T-cells to effectively bind to the tumour and destroy it.

       Conventional chemotherapy or immunotherapy comprises molecules that bind to the tumour or block chemical pathways that allow the tumour to grow or multiply – but don’t directly affect the immune system.

       In CAR T-cell therapy, the immune system is activated when the modified T-cells are reintroduced into the body, which allows a gradual and sustained tumour kill as these cells multiply.

 

Applications:

       As of today, CAR T-cell therapy has been approved for leukaemias (cancers arising from the cells that produce white blood cells) and lymphomas (arising from the lymphatic system).

       CAR T-cell therapy is also presently used among patients with cancers that have returned after an initial successful treatment or which haven’t responded to previous combinations of chemotherapy or immunotherapy.

 

Response of CAR T-cell therapy:

       Its response rate is variable. In certain kinds of leukaemias and lymphomas, the efficacy is as high as 90%, whereas in other types of cancers it is significantly lower.

       The potential side-effects are also significant, associated with cytokine release syndrome (a widespread activation of the immune system and collateral damage to the body’s normal cells) and neurological symptoms (severe confusion, seizures, and speech impairment).

       It is unaffordable to half of the Indians as it is costly.