Researchers at the Charbonneau Cancer Institute at the University of Calgary and McMaster University have developed an experimental chimeric antigen receptor (CAR) T-cell therapy, called GCAR1, which is showing promise against certain solid tumors. The work was reported in companion papers in Nature and Nature Cancer, according to a July 2 announcement.
Dr. Douglas Mahoney, director of the Riddell Centre for Cancer Immunotherapy at the Cumming School of Medicine and principal investigator on the Nature Cancer study, said, "We've developed a first-in-class CAR T cell therapy, called GCAR1, that is showing strong preclinical and early clinical promise in sarcoma and other cancers. Our colleagues at McMaster University have further demonstrated its potential in mouse models of a deadly brain cancer. This work reflects a close collaboration between the University of Calgary, Cancer Care Alberta, Alberta Precision Laboratories, and other key partners around the country, bringing discovery science and clinical expertise together at every step." Mahoney also said that Boreal Biomanufacturing played a key role by manufacturing the virus used to engineer CAR T cells, while BC Cancer provided critical reagents for biomanufacturing.
The therapy has been administered to two Canadian patients with alveolar soft-cell sarcoma. The first patient lived significantly longer than expected after receiving treatment; her doctors said her life expectancy was extended by 18 months. Dr. Sorana Morrissy led data analysis efforts from tissue samples collected before and after treatment. Morrissy said, "We anticipated learning something from Stéphanie's tissue and studied lung biopsies taken before and after treatment. We also generated data from dozens of blood samples, each comprising many thousands of cells." Insights from this data informed treatment for a second patient—a 55-year-old man—who received GCAR1 combined with another immunotherapy.
The second patient described his experience: "This clinical trial gave me hope. I was told there wasn't anything more that could be done to treat my cancer... After the second therapy the scans showed that many of the tumors shrank, and some had disappeared." Dr. Mona Shafey oversaw his care at Arthur J.E. Child Comprehensive Cancer Centre: "One of the lesions in Kent's lungs was over 2.5 centimeters in size, and now it's less than one centimeter... With research we can bring new experimental treatments to patients who have exhausted all standard treatments."
Dr. Franz Zemp noted rapid progress: "We have had laser focus on this new target since 2021... Within six months of building the medicine we had data back from mouse studies... That speed of translation from lab to clinic is remarkable." Researchers are studying tumor samples before and after GCAR1 therapy as they work toward advanced versions targeting markers found on kidney and brain cancers as well.
Support for this research came through philanthropic contributions along with grants from organizations including Canadian Cancer Society, Canadian Institutes of Health Research (CIHR), BioCanRx, Alberta Children's Hospital Foundation, and Alberta Cancer Foundation.
