Chimeric Antigen Receptor (CAR) T cell therapy involves genetically modifying a patient’s T cells to fight against malignant tumor cells.
T cells are a type of white blood cell developed from the stem cells in the bone marrow and are a vital part of the immune system, defending the body against infections
T-cells are collected from the patient through a process called leukapheresis.
They are then modified in the lab to express proteins called chimeric antigen receptors (CARs) on their surface.
The gene responsible for encoding CAR is developed synthetically in the lab, and a vector acts as a vehicle to deliver CAR into the patient’s T-cell.
Commonly, viral vectors, such as lentiviral vectors, are used, as seen in NexCAR19.
NexCAR19: India's Indigenously Developed CAR-T Therapy
NexCAR19 is designed to target cancer cells carrying the CD19 protein, a marker on cancer cells, enhancing precision in treatment.
It has been developed in India by ImmunoACT, which is a company incubated at IIT Bombay
The re-engineered T cells are then multiplied by millions in the lab and sent back to the hospital, where they are infused into the patient.
The patient usually undergoes chemotherapy before receiving the CAR-T cells.
The CAR comprises several components that enable it to identify cancer cell antigens and stimulate an immune response.
Each CAR spans across the cell membrane, with a portion extending outside the cell and a portion inside.
The exterior segment is made of fragments of laboratory-generated antibodies selected for their affinity to bind to the targeted antigen.
The internal segment of CAR consists of two components responsible for transmitting signalling once the receptor interacts with an antigen
While CAR-T therapy has shown remarkable progress in cases that looked hopeless, its efficacy varies from person to person, and it remains too early to declare it a complete cure.
Moreover, it entails several side effects, the cytokine release syndrome (CRS) being the most common — an inflammatory response triggering immune system hyperactivity.
Neurotoxicity is another common side effect but it wasn’t observed in any early-stage clinical trial patients, potentially because of the ‘humanised’ antibody fragments used.
Additionally, infections and low blood cell counts are other side effects doctors anticipate
While NexCAR19 is priced at a fraction of its U.S. counterpart, it remains relatively high for many Indians, ranging from ₹40 to 45 lakh
COMMENTS