First-in-human studies of CAR-T cell therapies for recurrent glioblastoma suggest the approach may eventually become useful for patients with this deadly type of brain cancer, researchers say.
The treatment involves removing a patients’ own T cells – a key component of the immune system – genetically altering them, and re-infusing them. The therapy, which has so far only been approved for a variety of blood cancers, shrank tumors in three separate early-stage glioblastoma trials designed primarily to test the safety of the approach.
In one trial, reported on Wednesday in The New England Journal of Medicine, three patients with recurrent glioblastoma were treated with CAR-T cells engineered to target various forms of epidermal growth factor receptor (EGFR) proteins on the tumor cell surface.
“Tumor regression was dramatic and rapid, occurring within days after receipt of a single… infusion,” researchers reported.
The tumors began to regrow within one to two months in two of the three participants, but the third patient’s response to treatment persisted through 150 days of follow-up.
“These results are exciting, but they are also just the beginning, they tell us that we are on the right track,” study leader Dr. Marcela Maus of Mass General Cancer Center in Boston said in a statement.
Since CAR-T therapy first came on the scene, researchers have been looking for ways it might treat solid tumor cancers.
In a separate early trial published on Wednesday in Nature Medicine, CAR-T cells targeting EGFR and a second cell-surface protein called Interleukin 13 receptor alpha 2 shrank tumors in all six patients with recurrent glioblastoma, although none shrank by at least 50%.
“Stable disease was maintained on scans performed at least 2 months after CAR T cell therapy in three of the four patients who had at least 2 months of follow-up time,” the researchers said.
The trial, funded in part by Gilead Sciences’ Kite Pharma unit, is ongoing, with future participants receiving incrementally higher doses of the treatment.
“We are energized by these results, and are eager to continue our trial, which will give us a better understanding of how this dual-target CAR T cell therapy affects a wider range of individuals with recurrent (glioblastoma),” study leader Dr. Donald O’Rourke of the University of Pennsylvania Perelman School of Medicine in Philadelphia said in a statement.
A third early stage trial published last week in Nature Medicine tested various doses of CAR-T cells targeting Interleukin 13 receptor alpha 2 in 65 patients with recurrent glioblastoma.
The treatment, licensed by Fortress Biotech’s Mustang Bio division, achieved stable disease or better in 50% of patients, the authors reported. Overall, half of the participants survived more than 8 months.
“These were heavily pretreated patients, so we were not sure how they would do with CAR T cell therapy,” senior author Dr. Behnam Badie of City of Hope in Duarte, California said in a statement. “But some of them even did better than how they initially responded to standard of care treatments.
Read more about CAR-T cell treatments on Reuters.com
