Serial Circulating Tumor DNA (ctDNA) Monitoring During Adjuvant Capecitabine in Early Triple-negative Breast Cancer

Eligibility Criteria

• 1. Anatomic stage I - III triple-negative breast cancer at diagnosis
• 2. Estrogen receptors (ER) and Progesterone receptors (PR) status \<10%
• 3. Residual disease following at least 4 cycles of neoadjuvant chemotherapy. Patients who received other investigational immunotherapy or targeted therapy during the neoadjuvant phase of treatment are eligible.
• 4. ≥ 18 years of age
• 5. Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2
• 6. All clinically significant toxic effects of prior cancer therapy resolved to Grade ≤ 1 by the National Cancer Institute Common Terminology Criteria for Adverse Events, version 5.0 (NCI CTCAE, v 5.0), except alopecia and G2 neuropathy.
• 7. No evidence of metastatic disease.
• 8. A minimum 4-week wash out from previous chemotherapy treatment is required.
• 9. Adequate hematologic function: Absolute neutrophil count (ANC) ≥ 1,500 cells/μL (≥ 1,500/mm3); Platelets ≥ 100,000 cells/μL (≥ 100,000/mm3)
• 10. Adequate hepatic function: Bilirubin ≤ 1.5 times the specific institutional upper limit of normal (ULN). Exception: If Gilbert's syndrome; then ≤ 5 times ULN. Aspartate transaminase (AST) and alanine transaminase (ALT) each ≤ 2.5 x ULN
• 11. Adequate renal function: Serum creatinine ≤ 1.5 x ULN; or calculated creatinine clearance \> 50 mL/min using the Cockcroft Gault formula.
• 12. Planned for 6 months or 8 cycles of adjuvant capecitabine.
• 13. Women of childbearing potential (WOCBP) must have a negative pregnancy test.
• 14. WOCBP must agree to use effective contraception during the study and for 3 months after the last dose.
• 15. Male participants and their female partners of child bearing potential must be willing to use an appropriate method of contraception during the study and for 3 months after the last dose.
• 16. Capable of giving signed informed consent, which includes compliance with requirements and restrictions listed in the informed consent form (ICF) and in the protocol
• 1. Metastatic breast cancer
• 2. Has not had definitive surgical resection
• 3. Pregnant or breastfeeding
• 4. Has not completed definitive adjuvant radiation if planned
• 5. Known human immunodeficiency virus (HIV) positivity or active hepatitis B or C.
• 6. Investigational agents within 4 weeks of study initiation
• 7. Inability to swallow oral medications