The world's first patient to be infused with base-edited T-cells is in remission for leukemia 28 days after receiving the gene therapy, according to the U.K.-based Great Ormond Street Hospital.
Six months after being treated with base editing — a technique that modifies the genetic code to reduce side-effect risk — and a second bone marrow transplant, the 13-year-old patient, Alyssa, is still in remission and is doing well, according to a GOSH news release.
It's tricky to treat T-cell leukemia with traditional CAR T-cell therapy because T-cells will kill each other before they can be used in treatments, but by altering a donor's CAR T-cells, base editing ensures the cells only attack cancerous ones and not themselves.
Alyssa was diagnosed with leukemia in May 2021, and despite receiving chemotherapy and a bone marrow transplant, full remission couldn't be achieved.
"Only after she received her CD7 CAR-T cell therapy and a second bone marrow transplant in GOSH she has become leukemia free," Robert Chiesa, MD, a bone marrow transplant consultant at GOSH, said in a statement. "This is quite remarkable, although it is still a preliminary result, which needs to be monitored and confirmed over the next few months."
The researchers plan to recruit 10 patients with T-cell leukemia "who have exhausted all other treatment options" to further test the base editing technique.