AstraZeneca reported that Etcamah (camizestrant) failed to meet its primary goal in a Phase 3 setting designed to support earlier use in advanced ER-positive, HER2-negative breast cancer. The company said Etcamah, tested with standard hormone therapy and in combination regimens, did not significantly delay disease progression versus the comparator. The disappointment follows a separate accelerated FDA clearance just weeks earlier in a biomarker-selected setting tied to ESR1 detection by an FDA-approved test. AstraZeneca framed the regimen readout as showing only a numerical improvement without statistical significance. For the market, the update reinforces the difficulty of translating oral SERD efficacy into broad first-line settings and increases emphasis on ESR1-mutant subsets for label positioning.