UPDATE 1 — FDA advisers back safety of Grail's cancer test, narrowly endorses efficacy
(Adds details and background throughout) Sept 23 (Reuters) — A panel of outside experts advising the US FDA backed the safety of Grail's blood-based cancer detection test, Galleri, on Wednesday, but was divided on the evidence supporting its effectiveness. While all the 10 panel members unanimously backed Galleri's saf