Introduction/aim: The combination of CDK4-6i and endocrine therapy (ET) is standard-of- care for pts with HR+/HER2- advanced breast cancer. However, studies evaluating adjuvant CDK4-6i provided contradictory results thus far. We conducted a systematic review and meta-analysis to assess if the addition of CDK4-6i to adjuvant ET impacts on survival’s outcomes and safety of pts with HR+/HER2- EBC.