US clears breakthrough gene therapy for childhood leukemia

US health officials have approved a breakthrough treatment that genetically engineers patients' own blood cells into an army of assassins to seek and destroy childhood leukemia.
The Food and Drug Administration calls the approval historic, the first gene therapy to hit the US market. Made from scratch for every patient, it's one of a wave of "living drugs" under development to fight additional blood cancers and other tumors, too.
Novartis Pharmaceuticals has set the price for its one- time infusion of so-called "CAR-T cells" at $475,000, but says there would be no charge for patients who didn't show a response within a month.