Top FDA of­fi­cials on Wednes­day sketched out a new reg­u­la­to­ry ap­proach that aims to keep pace with sci­en­tif­ic ad­vances in per­son­al­ized med­i­cine. It builds off the cel­e­brat­ed case of Ba­by KJ, who was treat­ed with a cus­tom gene ther­a­py...