New Delhi: An indigenously developed gene therapy for specific blood cancers has shown a 73 per cent response rate among patients in India, according to results of clinical trials published in The Lancet Haematology journal. Known as ‘CAR T-cell therapy‘, the treatment involves modifying genes in one’s T-cells — a type of immune cells — to help fight cancer. The study looked at patients with leukaemia, which occurs in bone marrow, and lymphoma, which affects the lymphatic system.
Researchers, including those from the Indian Institute of Technology-Bombay and Tata Memorial Hospital, Mumbai, said in low and middle-income countries, patients in whom ‘B-cell’ tumours continue to grow following a period of remission (relapse), or do not respond to treatment (refractory), suffer from poor outcomes due to an absence of effective therapies.
A type of white blood cell, B-cells are crucial to one’s immune system as they produce antibodies to fight infections.
“The clinical trials of India’s first gene therapy for cancer offer hopes of another chance to live among these patients, that there is one more drug that doctors can try,” lead author Rahul Purwar, professor at IIT-Bombay and founder of ImmunoACT, told PTI.
‘ImmunoACT’, or ImmunoAdoptive Cell Therapy Private Limited, is a gene-modified cell therapy company, a spinoff of IIT Bombay.
The CAR T-cell therapy is also a cost-effective alternative to that available in the developed world, Purwar added.
“We developed it over a period of 11 years, starting with drug design and lab work, which was then translated into animal studies, before progressing to clinical trials,” he said.
The injection ‘talicabtagene autoleucel‘ is now approved in India, “available for USD 30,000,” which is “less than one-tenth of the price of other approved CD19 CAR T-cell therapy products marketed worldwide,” the authors wrote.
In a linked commentary article, authors from the University of Pennsylvania, US, and not involved in the study, wrote, “Approved CAR T-cell products cost USD 373,000-475,000, and clinical care and possible relocation expenses bring the total treatment cost to over (one million USD).”
“Therefore, access to CAR T-cell therapy is an important limitation to the success of this approach in not only high-income countries but particularly in low-income and middle-income countries,” they wrote.
In phase-1 of the India trials, talicabtagene autoleucel was injected into the veins of 14 patients aged 18 years or older having relapsed or refractory B-cell lymphoma. In phase-2 trials, the drug was given to 50 patients aged 15 years and older with relapsed or refractory B-cell leukaemia or B-cell lymphoma.
The typical age of the overall study group was 44 years. Of the 64 patients, 49 were men and 15 women.
While phase-1 trials assess a new drug’s safety in 20-100 volunteers, along with how the drug is absorbed and metabolised in the body, phase-2 trials involve 100-300 participants for the testing of the new drug’s effectiveness.
Among the 51 patients analysed, “the overall response rate was 73 per cent,” the authors wrote.
There were two treatment-related deaths, and the most common toxicities were neutropenia (unusually low count of neutrophils), which affected 55 of 57 patients, followed by thrombocytopenia (a low platelet count), which affected 37 of them, the team said.
Anaemia was found to affect 35 patients.
“Talicabtagene autoleucel had a manageable safety profile and induced durable responses in patients with relapsed or refractory B-cell malignancies,” the authors wrote.
“This therapy addresses an important unmet need for patients with relapsed or refractory B-cell malignancies in India,” they wrote.
