Efficacy and Safety of Camizestrant Plus Ribociclib in Patients With Breast Cancer

This trial will study a type of breast cancer defined by the expression of hormone receptor in the cancer cells (HR+). Patients will be treated with ribociclib, a cyclin-dependent kinase inhibitor, and camizestrant, a selective estrogen receptor degrader (SERD) and complete ER antagonist. The main purpose of the Study is to analyze the efficacy (to find out how effective a treatment is) of ribociclib in combination with camizestrant in patients with advanced HR+ breast cancer who have received endocrine therapy (ET) in early breast cancer setting for at least 5 years, of which at least 2 years with aromatase inhibitor (AI). Ribociclib plus camizestrant efficacy will be determined by assessing the period from treatment initiation until disease progression, defined as progression free survival (PFS). The anticipated favorable clinical benefits of the combination of ribociclib and camizestrant therapy are projected to outweigh the risks of this treatment. This Study will be performed in full compliance with International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) and all applicable local Good Clinical Practice (GCP) and regulations.