Arnold Lee
Camizestrant (Etcamah®) is an orally available, potent selective estrogen receptor degrader (SERD) and complete estrogen receptor (ER) α antagonist being developed by AstraZeneca for the treatment of breast cancer. It received its first approval in the United Arab Emirates (UAE) in May 2025. At the time of writing, the drug had been subsequently approved in Saudi Arabia, Japan, the EU, Canada, the UK and the USA. In patients with ER-positive and human epidermal growth factor receptor 2 (HER2)-negative breast cancer with a detectable ESR1 mutation, switching to camizestrant while continuing the same CDK4/6 inhibitor significantly prolonged progression-free survival in comparison with continuing treatment with an aromatase inhibitor in combination with a CDK4/6 inhibitor. This article summarizes the milestones in the development of camizestrant leading to this first approval for the treatment of adults with locally advanced or metastatic hormone receptor positive (HR+), HER2-negative breast cancer with an ESR1 gene mutation that emerges during first-line hormonal therapy, in combination with CDK4/6 inhibitors.