Novel cancer therapy works for 73 per cent Indian patients in clinical trials: Why the Lancet report is significant

This is the first clinical trial of a CAR T-cell therapy from India to be published in an international journal. “This is really a world class innovation done within the country. The treatment has been found to be comparable to others approved globally and the  cost is 1/20th of those therapies. This will improve access and affordability of such high-end cancer treatments,” the Lancet commentary said.

What is CAR T-cell therapy?

CAR T-cell therapy, or chimeric antigen receptor T-cell therapy, trains the body’s own immune cells to identify and destroy cancer cells. This treatment is designed for specific types of blood cancer and is given to patients whose cancer has either relapsed or not responded to first-line treatment.

Based on unpublished, yet-to-be peer-reviewed results, India’s drug regulator had granted approval for this therapy in 2023. It is now available at several hospitals across India, including Apollo, Fortis, Amrita and Max, among others.

Given that the treatment is novel and intended for cancer patients with no other options, the regulator allowed the company — a start-up incubated in IIT Bombay called ImmunoAct — to forgo a large Phase III clinical trial to demonstrate its efficacy in a broader population. However, the company must follow up with all patients who receive the therapy for 15 years.

What were the Lancet findings?

Along with a response rate of 73%, the study reported an average six months survival without any progression in acute lymphoblastic leukaemia patients and four months in lymphoma patients.

Are there side-effects?

While the response rate was found to be similar to other therapies approved across the world, there was high incidence of haemophagocytic lymphohistiocytosis — a serious but known complication of CAR T therapies where the immune cells get uncontrollably activated leading to hyper inflammation and organ damage.

This complication was seen in 12% of the study participants, leading to the death of at least one of the patients. The study reported one other treatment-related death caused by bleeding in the lungs and multi-organ failure.

The most common side effects reported by the study were anaemia in 61% participants, thrombocytopenia (low platelet count increasing the risk of bleeding) in 65% patients, neutropenia (low count of white blood cells called neutrophils) in 96% patients, and febrile neutropenia (neutropenia along with fever) in 47% of the patients. These were already extremely sick cancer patients who failed to respond to other treatments.

How does the therapy work? 

For any CAR T-cell therapy, a patient’s immune T-cells are collected by filtering their blood. These cells are then engineered in a lab to add receptors that can bind with cancer cells. These cells are then multiplied and infused in the patient. Usually, the cancer cells are adept at evading the unmodified T cells. The treatment developed in India is meant for patients with two types of blood cancers that affect the B cells — acute lymphoblastic leukemia and large B cell lymphomas.

Why is the treatment important?

Access to cutting-edge cancer treatment like CAR T-cell therapy remains restricted to a handful of countries owing to the technological challenges as well as the cost associated with the treatment. “The only countries or regions with access to at least one anti-CD19 CAR T-cell product are the USA, EU, UK, Japan, Australia, Singapore, Israel, Switzerland, Brazil, South Korea, Canada and China,” the commentary said.

The commentary states: “Approved CAR T-cell products cost US$373 000–475 000, and clinical care and possible relocation expenses bring the total treatment cost to over US$1 000 000… (This therapy) was marketed at a relatively low cost of approximately US$30 000.” This translates to around Rs 25 lakh.