Grail reported that its NHS‑Galleri multicancer early detection (MCED) trial did not meet the study’s primary endpoint of a statistically significant reduction in stage III–IV cancers. The topline announcement accompanied full‑year financial results and prompted an immediate market reaction, with shares falling roughly half their value in after‑hours trading. The company said there were favorable trends in a pre‑specified group of 12 deadly cancers and plans to extend follow‑up by up to a year; Grail also indicated the readout should not alter its ongoing FDA premarket approval review. Independent experts quoted in the company call and press coverage characterized the result as a major setback that will complicate payor, regulatory and public‑health adoption discussions for MCED tests.