Capivasertib After Progression on CDK4/6 Inhibitor Combined with Endocrine Therapy in a Patient with HR-Positive, HER2-Negative Metastatic Breast Cancer: A Case Report

Capivasertib, an AKT inhibitor, combined with fulvestrant, has demonstrated significantly improved progression-free survival compared with fulvestrant alone in patients with hormone receptor (HR)-positive advanced breast cancer whose disease progressed during or after previous aromatase inhibitor therapy with or without a cyclin-dependent kinase 4/6 (CDK4/6) inhibitor. This report presents a patient with HR-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer who achieved clinical benefit with capivasertib following disease progression after endocrine therapy, including ovarian suppression, aromatase inhibitors and fulvestrant, as well as chemotherapy and treatment with the CDK4/6 inhibitor palbociclib in combination with letrozole. PEER REVIEWED ARTICLE Peer reviewers: Dr Alin Chirindel, University Hospital Basel, Basel, Switzerland One anonymous peer reviewer Received on November 20, 2024; accepted after peer review on December 20, 2024; published online on December 27, 2024.