This is a low-intervention, randomized, non-comparative, open-label, multicenter, prospective, phase II trial investigating discontinuation of CDK4/6 inhibitors in patients with metastatic HR positive, HER2 negative breast cancer with durable disease control.
Female patient has given written informed consent
Patient is ≥ 18 years of age at time of signing the written informed consent
Patient has been diagnosed with histologically confirmed metastatic adenocarcinoma of the breast
Patient has documented histological or cytological confirmation of estrogen receptor positive (ER+) and HER2 negative (HER2-) disease
Patient has active (or history of) brain or leptomeningeal metastases
Patient is pre- or perimenopausal. Patient is pregnant or breast feeding or planning to become pregnant within five times the half-life of the IMPs after the end of treatment.
Patient has significant cardiovascular disease, such as cardiac disease (New York Heart Association Class II or greater), myocardial infarction or cerebrovascular accident within 6 months prior to initiation of study treatment, unstable arrhythmias, or unstable angina
Patient has other concomitant or previous malignancy, except adequately treated in-situ carcinoma of the uterine cervix, basal or squamous cell carcinoma of the skin, cancer in complete remission for > 5 years