Homegrown CAR-T cells ‘cure’ 8-yr-old’s leukaemia
Mumbai: Three months ago, eight-year-old Indu Shirke’s parents were told she had only a few more weeks to live as her leukaemia had relapsed. Doctors at Tata Memorial Hospital, where Indu (not her real name) was under treatment since 2020, offered them an option: a homegrown version of a gene therapy that had shown promise in at least 50% of the patients it was used for in the West.
Her father, Baban Shirke (name changed), a driver in a village near Igatpuri, said there was no reason to turn it down as her condition was “bad”. “CAR-T saved her,” he told TOI. When the family visited ACTREC, Tata Memorial Centre’s research block in Kharghar earlier in the week, doctors told them no cancer cells could be detected in her blood. “She is eating normally for the first time in two years,” he added.CAR-T cells are a new form of immunotherapy, itself a fledgling branch of cancer treatment (see box). It entails re-engineering the body's T immune cells with some genetic material so that they selectively target cancer cells for destruction.
The eight-year-old got the treatment as part of the safety trials for India’s first indigenously made CAR-T cells — a joint effort between IIT-Bombay and Tata Memorial Centre, Mumbai (the first patient was infused on June 6, 2021). This made-in-India therapy’s price tag will be a 10th of its cost in the US, said IIT-B scientist Dr Rahul Purwar who is driving the project.
Last month, the group announced “encouraging” results of the Phase 1 trial for 10 patients with lymphoma. Last week, Dr (Surg Cdr) Gaurav Narula from TMC announced similar results for the safety trial for six patients of leukemia at a medical conference in Kochi. “For a group of patients who had no known options, these were very encouraging results and in line with published data of other CAR-T products in other parts of the world,” said Dr Narula. Each of these patients had received three to five lines of therapy, including previous stem cell transplant, but in vain.
TMC deputy director Dr Navin Khattry said although “it’s early days yet” with CAR-T cells, the Indian product has proved to be safe. “We found it has low toxicity as compared to the western CAR-T cells. For instance, 33% of the western patients develop some level of neurological toxicity, but this wasn’t seen in our patients. Moreover, none of our patients developed cytokine storms (when the body’s immune system responds too aggressively to infection),” said Dr Khattry.
Another eight-year-old boy who underwent CAR-T infusion over six months back is also cancer-free at the moment. Only one of the six patients didn’t have any response to CAR-T cells. Another patient, who responded well initially, passed away 16 months later after undergoing a bone marrow transplant.
Doctors hope the 8-year-old girl and other patients in the future have the same response as American youngster Emily Whitehead, who was the first patient in the world to undergo CAR-T cell therapy 10 years back. She didn’t need any therapy thereafter and has been cancer free since 2012.
According to the girl’s father, doctors first collected his daughter's blood through a special process for collecting white blood cells. Thereafter, her T cells were gathered from the white blood cells and “trasduced” with a viral vector (tools used to deliver genetic material into cells). “This is done in order to get the T Cells to express certain antibody,” said Dr Narula.
These modified T Cells were then multiplied in the high-tech laboratory at IIT Bombay. A battery of tests was done to check for toxicity before it was given as a single infusion to the patient.
“We were in ACTREC for 30 days and came back to Igatpuri,” said the father. She has go back for a checkup in early November.
As for the IIB-TMC team, it is preparing for the second phase of the clinical trial in which 50 patients will be given CAR-T cells. Purwar, who has since set up ImmunoACT Laboratory, said, “We are also working on gene therapy for various other cancers, including solid tumours,'” he said, adding that the goal is to make gene therapy affordable to many more Indians.
