On September 4, 2026, the FDA granted accelerated approval to ETCAMAH (camizestrant) in combination with a CDK4/6 inhibitor for adults with HR-positive, HER2-negative metastatic or locally advanced breast cancer who develop an ESR1 mutation while receiving first-line aromatase inhibitor therapy. The decision introduces a new, mutation-guided treatment strategy aimed at intercepting endocrine resistance before clinical progression—a shift many oncologists have been anticipating.