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

The Primary Objective is to characterize the circulating tumor DNA (ctDNA) profile of triple-negative breast cancer (TNBC) in participants with residual disease after standard neoadjuvant chemotherapy (NAC) receiving standard-of-care adjuvant capecitabine.

The Secondary Objectives are to correlate ctDNA levels with genomic features and survival.

Inclusion criteria

• Anatomic stage I - III triple-negative breast cancer at diagnosis
• Estrogen receptors (ER) and Progesterone receptors (PR) status <10%
• 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.
• ≥ 18 years of age
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2
• 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.
• No evidence of metastatic disease.
• A minimum 4-week wash out from previous chemotherapy treatment is required.
• Adequate hematologic function: Absolute neutrophil count (ANC) ≥ 1,500 cells/μL (≥ 1,500/mm3); Platelets ≥ 100,000 cells/μL (≥ 100,000/mm3)
• 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
• Adequate renal function: Serum creatinine ≤ 1.5 x ULN; or calculated creatinine clearance > 50 mL/min using the Cockcroft Gault formula.
• Planned for 6 months or 8 cycles of adjuvant capecitabine.
• Women of childbearing potential (WOCBP) must have a negative pregnancy test.
• WOCBP must agree to use effective contraception during the study and for 3 months after the last dose.
• 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.
• Capable of giving signed informed consent, which includes compliance with requirements and restrictions listed in the informed consent form (ICF) and in the protocol

Exclusion criteria

• Metastatic breast cancer
• Has not had definitive surgical resection
• Pregnant or breastfeeding
• Has not completed definitive adjuvant radiation if planned
• Known human immunodeficiency virus (HIV) positivity or active hepatitis B or C.
• Investigational agents within 4 weeks of study initiation
• Inability to swallow oral medications