ASTRINGOF FIRSTS

The year started with no gene therapies sold in the U.S. and only a couple elsewhere. Then the Food and Drug Administration ap- proved the first CAR-T cell therapies, which alter a patient’s own blood cells to turn them into specialized cancer killers . They’re only for certain types of leukemia and lymphoma now, but more are in the works for other blood cancers.

Last week, the FDA approved Luxturna, the first gene therapy for an inherited disease, a form of blindness. People with it can’t make a protein needed by the retina, tissue at the back of the eye that converts light into signals to the brain, enabling sight. The therapy injects a modified virus containing a corrective gene into the retina so the cells canmake the protein.

Children who received the treatment told what it was like to gain vision.

“Oh yikes, colors. Colors are super fun,” said 13-yearold Caroline Carper of Little Rock, Arkansas. “And the sunshine is blinding.”

Gene therapies also showed some promise against a variety of diseases including hemophilia , a blood clotting problem; “bubble boy” disease, where a f lawed immune system leaves patients vulnerable to fatal infections, and sickle cell disease, a serious and painful blood disorder common among black people.

It’s not all good news, though. The therapies don’t work for everyone. They’re shockingly expensive. And no one knows how long some results will last, though scientists say the aimis a one-time repair that gets at the root cause.

“The whole promise ... is to cure diseases. It’s based on the rationale of fixing the problem,” not just improving treatment, said Dr. Carl June, a University of Pennsylvania scientist who pioneered CAR-T therapy.

A NEW FRONTIER: GENE EDITING

In mid-November, Brian Madeux, a 44-year- old Phoenix man with a metabolic disease called Hunter syndrome, had just become the first person to try an experimental gene editing treatment.

“I believe in science,”