This clinical trial is focused on studying the effects of stopping certain medications in patients with metastatic HR-positive, HER2-negative breast cancer. This type of breast cancer is characterized by the presence of hormone receptors (HR) and the absence of a protein called HER2. The study involves medications known as CDK4/6 inhibitors, which include abemaciclib, ribociclib, and palbociclib. These medications are used in combination with endocrine therapy, which includes drugs like letrozole, fulvestrant, exemestane, and anastrozole. The purpose of the study is to evaluate whether stopping CDK4/6 inhibitors after a prolonged period of treatment can maintain disease stability in patients who have shown at least stable disease for 12 months.
Participants in the study will be randomly assigned to either continue or discontinue the CDK4/6 inhibitors while continuing with endocrine therapy. The study will monitor the patients over a period to see if the cancer remains stable without the CDK4/6 inhibitors. The main focus is to observe the progression-free survival rate, which means the length of time during and after the treatment that the patient lives with the disease without it getting worse. This will be assessed through imaging tests to check for any signs of cancer progression.
The trial aims to provide insights into the long-term management of metastatic HR-positive, HER2-negative breast cancer by understanding the effects of discontinuing CDK4/6 inhibitors. This could potentially lead to new strategies for maintaining disease control while minimizing medication use. The study is expected to run until 2028, with recruitment starting in late 2023.



Germany