Washington, Jan. 15 (Reuters): The US Food and Drug Administration said today it was halting about 30 gene therapy trials after learning that a second child in a French gene therapy experiment has leukaemia.
The two boys in France were diagnosed with leukaemia after receiving the experimental treatment for “bubble boy disease” — X-linked severe combined immunodeficiency, or SCID.
A genetic defect leaves such children — always boys — without an immune system. Without treatment, they can die of infections that would hardly affect a healthy child.
The gene therapy, which reinforces the children’s bone marrow with genetically engineered immune cells, had worked remarkably well in the children. They had seemingly been cured of SCID before the leukaemia symptoms began and were among 10 gene therapy patients in France who were living normal lives.
Both leukaemia patients are apparently being helped by chemotherapy, said Dr Philip Noguchi, head of gene therapy issues at the FDA. “We do know that both children, the first one and second one, are clinically stable,” he said.
The French researchers declined to comment.