Sequential Therapies Modeled on Evolutionary Dynamics for Breast Cancer

Inclusion Criteria

• •Female patients 18 years or older
• •Histologically or cytologically confirmed diagnosis of hormone positive HER2 negative metastatic breast cancer per ASCO/CAP criteria (Allison et al, 2020, Wolff et al, 2018), with diagnosis established through either a breast/axillary biopsy or biopsy of a metastatic lesion.
• •Hormone positive MBC previously treated with endocrine therapy with either an aromatase inhibitor or Tamoxifen (alone or in combination with a CDK4/6 inhibitor).
• •Elevated breast tumor markers which may include cancer antigen 15-3 (CA 15-3) levels above the institutional upper limit of normal (ULN) range of 0.0-31.0 U/mL, cancer antigen 27-29 (CA 27-29) (range \<38 U/mL) and/or elevated Carcinoembryonic antigen (CEA) above institutional upper limit of normal (range 0.0 - 5.2 ng/mL).
• •Presence of measurable disease on imaging via RECIST v1.1.
• •ECOG performance status 0-1.
• •Participants must have adequate organ and marrow function as defined in the protocol.
• •A negative pregnancy test for pre-menopausal women of childbearing potential.
• •Pre-menopausal women of childbearing potential who are sexually active with a male partner must agree to use adequate contraception prior to the study, for the duration of study participation.
• •Concurrent or prior use of immunosuppressive medication within 14 days before the first dose of study drugs, with the following exceptions: premedication with dexamethasone, intranasal, inhaled, topical or local steroid injections, systemic corticosteroids at physiologic doses not exceeding 10 mg/day of prednisone or its equivalent; steroids as premedication for hypersensitivity reactions (e.g., premedication for iodinated contrast allergy before CT scan).
• •Inability to comply with protocol requirements.
• •Pregnant and/or breastfeeding women are excluded.