Study of Ribociclib With Everolimus + Exemestane in HR+ HER2- Locally Advanced/Metastatic Breast Cancer Post Progression on CDK 4/6 Inhibitor.

Inclusion Criteria:

Adult men and women
Patient has a confirmed diagnosis of estrogen-receptor positive and/or progesterone receptor positive breast cancer by local laboratory and has HER2-negative breast cancer
Patient must have either measurable disease by RECIST 1.1 or bone lesions in absence of measurable disease.
ECOG Performance Status 0 - 1
Disease refractory to either, AI, tamoxifen or fulvestrant
Previously treated on any CDK 4/6 inhibitor.
Patient has adequate bone marrow and organ function.

Exclusion Criteria:

Patient with symptomatic visceral disease or any disease burden that makes the patient ineligible for endocrine therapy per the investigator's best judgment.
Patient has received more than one line of chemotherapy for advanced disease.
Previous treatment with mTOR inhibitors, or exemestane for advanced disease.
Progressed on more than one CDK 4/6 inhibitor
Patient with CNS involvement unless they are at least 4 weeks from prior therapy completion.
Clinically significant, uncontrolled heart disease and/or recent cardiac events.