Global Health Asia-Pacific July 2022 - Page 41

What is CAR T-cell Therapy ? T-cells or T-lymphocytes are a type of white blood cells in our immune system . T-cells have the capacity to recognise abnormal cells or any cells infected by viruses in the body , and then destroy these abnormal cells . However , T-cells may sometimes fail to recognise or eliminate these threats in the body , such as in the case of cancer .
CAR T-cell Therapy is a form of immunotherapy where T�cells are taken from the patient ’ s blood and modified in a laboratory setting to enable the T-cells to identify and destroy specific cancer cells . The modified T�cells are then reinfused into the patient ’ s body to detect cancer cells and destroy the cancer by harnessing the body ’ s own immune response .
Chimeric antigen receptor T-cell
CAR T-cell
CAR Chimeric Antigen Receptor
How does it work ?
Step 1 Screening and collection of T-cells The patient will first undergo screening and a series of tests to determine if CAR T-cell Therapy is an appropriate treatment option for their disease , and to ensure that the patient is fit to undergo treatment . White blood cells , which include T-cells , will be extracted from the patient ’ s blood using a procedure called leukapheresis . During this procedure , two intravenous infusion ( IV ) lines will be inserted into the patient : blood is extracted through one line , to allow the white blood cells to be separated out and extracted , while the rest of the blood is returned to the patient ’ s body through the second line .
Bridging treatment may also be required after the procedure to control the disease while waiting for the CAR T-cells to be infused ( in Step 4 ).
Step 2 Making the CAR T-cells When the white blood cells have been extracted , the T-cells will be separated out and sent to the laboratory to be altered . This alteration is carried out by adding the specific CA� gene to the T�cells , hence modifying them into CAR T-cells . These cells will then be grown and multiplied in the laboratory . Under normal circumstances , it can take 2 – 3 weeks to produce the adequate number of CAR T-cells required for CAR T-cell Therapy .
Step 3 Preparing the body for infusion A short chemotherapy cycle , called lymphodepletion , will be administered a few days before the infusion of CAR T-cells . This is done to lower the number of other immune cells in the body and prepare the body to receive the CAR T-cells .
Step 4 Infusion of CAR T-cells When enough CAR T-cells have been produced , the
T-cells that have been genetically engineered to produce an artificial T-cell receptor for use in immunotherapy
product will be shipped back to the hospital to be infused into the patient . Once the CAR T-cells begin binding with cancer cells in the body , they will begin to increase in number and destroy even more cancer cells .
Step 5 Recovery and follow-up Patients receiving CAR T-cell Therapy will have an early recovery period of approximately 6 – 8 weeks . During this period , patients will be monitored for any side effects and assessed on treatment response . Foreign patients will be required to be in Singapore throughout the entire process , which usually takes about 3 – 4 months from screening to recovery , depending on their individual condition .
Will I need to be hospitalised for undergoing the procedure ? Hospitalisation of 1 – 2 days is required at the start of the CAR T-cell Therapy . This hospital admission is for leukapheresis , a procedure where white blood cells , which include T-cells , are extracted from the patient ’ s blood .
Bridging treatment may also be required after leukapheresis to control the disease while waiting for the CAR T-cells to be infused .
A short chemotherapy cycle , called lymphodepletion , will be administered a few days before infusion to prepare the body to accept the CAR T-cells . During this period , readmission to hospital is required .
CAR T-cell Therapy is a form of immunotherapy where T-cells are taken from the patient ’ s blood and modified in a laboratory setting to enable the T-cells to identify and destroy specific cancer cells .
GlobalHealthAsiaPacific . com JULY 2022
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