The therapy, known as CAR-T cell therapy, involves taking a blood sample from a patient, extracting immune system cells called T-cells from it, genetically modifying them in the laboratory so they can detect and kill cancer cells better, then injecting them back into the patient. The modified T-cells remain in a patient's body, multiplying and providing long-term protection.
One study, led by Professor Carl June of the University of Pennsylvania, was centered on ten patients with chronic lymphocytic leukemia (CLL). Over 3500 GLINK(#:2488, diagnoses)} of CLL are made yearly in the UK and result in over 1000 deaths.
All patients in the study had mutations associated with high-risk CLL and were unresponsive to the standard drug treatment of ibrutinib. During the trial patients received a combination of ibrutinib and a CAR-T cell therapy called CTL119 over three consecutive days.
After three months, there was no evidence of disease in eight of nine patients who could be evaluated. All eight patients remained without signs of disease at a median of six months after treatment.
The study's first author, Dr Saar Gill of the University of Pennsylvania, explained: 'Combining ibrutinib with the CTL119 therapy achieved very powerful results for these patients, and with limited toxicity. This newer, coupled approach gives us hope that personalized cell therapies could be an important option for high-risk CLL patients on these types of drugs.'
In a second trial, researchers at Xi'an Jiaotong University, China, gave CAR-T cell therapy over a week to 35 patients with multiple myeloma, another type of blood cancer, who were not responding to standard treatment. Over 115,000 diagnoses of multiple myeloma are made each year worldwide.
Ten days after treatment all patients displayed a reduction in cancer size, and 33 patients showed clinical remission within two months of treatment.
Of 19 patients who could be evaluated after four months, 14 achieved a complete loss of evidence of disease (complete response), and five achieved partial response. Five of the patients with a complete response remain disease-free a year later.
The researchers intend to expand the study to include 100 people in China, and launch another study in the US.
'Although recent advances in chemotherapy have prolonged life expectancy in multiple myeloma, this cancer remains incurable,' said study author Dr Wanhong Zhao of Xi'an Jiaotong University. 'It appears that with this novel immunotherapy there may be a chance for cure in multiple myeloma, but we will need to follow patients much longer to confirm that.'
Patients from both studies experienced side effects of CAR T-cell therapy, but this was manageable in all patients.
The two clinical trials were presented at the 2017 American Society of Clinical Oncology Annual Meeting.