Phase II, multicenter, single arm trial to assess the feasibility of first line ribociclib in combination with a non steroidal aromatase inhibitor in women or men aged 70 years-old or older, with hormone receptor positive/HER2 negative advanced breast cancer

Elderly patients are generally more susceptible to the side effects of active treatments. Patients entered in clinical trials, especially the elderly, are not completely representative of the "real" population because of selection process. The lack of data collected from a real population turns the indication of treatment a challenging task and expose older patients to a risk of under treatment (fear of excessive toxicity because of the lack of data). With the aim of covering this gap, we are planning to run a phase II trial evaluating the feasibility of delivering the combination of ribociclib plus NSAI as first-line treatment specifically in a population of breast cancer patients aged ≥70 years. Primary endpoint: • The treatment feasibility will be evaluated as the proportion of patients not having experienced disease progression (PD), still on treatment with ribociclib plus NSAI 6 months after the first drug administration Secondary endpoints: * Treatment adherence * Safety and tolerability * Patient reported outcomes (PROs) * Overall response rate (ORR) * Progression free survival (PFS)