AstraZeneca PLC: US FDA decision date on camizestrant extended

The US Food and Drug Administration (FDA) has extended its Prescription Drug User Fee Act (PDUFA) review deadline for AstraZeneca’s New Drug Application (NDA) for camizestrant. The drug, combined with a CDK4/6 inhibitor, is intended for first-line treatment of patients with hormone receptor (HR)-positive, HER2-negative advanced breast cancer whose tumors develop an ESR1 mutation. The FDA’s decision comes after the Oncologic Drugs Advisory Committee in April 2026 failed to reach a majority vote on the drug’s benefit based on the SERENA-6 Phase III trial results. The NDA relies on data from the SERENA-6 trial, which was presented at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting and published in *The New England Journal of Medicine*. The FDA previously granted Breakthrough Therapy Designation for the camizestrant combination in May 2025. In response to the FDA’s request, AstraZeneca has submitted additional analyses, including ctDNA clearance data linked to long-term efficacy, which will be presented at ASCO 2026 on June 2. Susan Galbraith, Executive Vice President of Oncology Haematology R&D at AstraZeneca, stated the company remains committed to advancing oncology treatments. She emphasized the potential of the SERENA-6 strategy, which involves monitoring ESR1 mutations in circulating tumor DNA (ctDNA) and switching therapy to improve patient outcomes. The FDA’s extended review will allow further evaluation of these new data. Meanwhile, the European Medicines Agency (EMA) has already adopted a positive opinion for the camizestrant combination in the same setting, based on SERENA-6 results. The drug is already approved in the United Arab Emirates and Saudi Arabia, with regulatory reviews ongoing in Japan and other countries. Camizestrant targets HR-positive breast cancer, the most common subtype, which accounts for 70% of cases. While endocrine therapies and CDK4/6 inhibitors are standard treatments, resistance often develops, highlighting the need for new solutions like camizestrant.