Comparing UTD2 Combined With Capecitabine to Capecitabine as Adjuvant Therapy for Non-pCR TNBC Patients

Inclusion Criteria:

1. Informed Consent and Compliance The patient has fully understood this study andvoluntarily signed the informed consent form, demonstrating the ability andwillingness to comply with the study protocol-defined visits, treatment plans,laboratory tests, and other study procedures.

2. Age and Gender Female patients aged 18 to 70 years old (inclusive) on the day ofsigning the informed consent.

3. Prior Neoadjuvant Chemotherapy without pCR Received prior neoadjuvant chemotherapycontaining anthracycline or taxane agents without achieving pathological completeresponse (pCR). Neoadjuvant chemotherapy requirement: At least 4 completed cycles. Non-pCRdefinition: Residual invasive carcinoma confirmed by pathology after primary tumorresection.

4. Surgical Resection Underwent complete surgical resection (R0) with pathologicallyconfirmed negative margins.

5. Triple-Negative Breast Cancer Confirmation Post-resection tumor tissue confirmed as ER-negative, PR-negative, and HER2-negativebreast cancer by immunohistochemistry (IHC): ER-negative: <1% expression by IHC. PR-negative: <1% expression by IHC.HER2-negative: IHC score of 0 or 1+, or 2+ with negative in situ hybridization (ISH)results.

6. Postoperative Treatment No prior systemic anticancer therapy (excludingradiotherapy) after breast cancer surgery.

7. Performance Status ECOG performance status of 0 to 1.

8. Hematological Criteria (within 1 week prior to enrollment) Blood tests meet the following criteria (CTCAE v5.0 ≤ Grade 1, based oninstitutional laboratory standards): White blood cell (WBC) count ≥ 3.0 × 10^9/L. Absolute neutrophil count (ANC) ≥ 1.5 × 10^9/L. Platelet (PLT) count ≥ 100 × 10^9/L. Hemoglobin ≥ 9.0 g/dL. Noadministration of recombinant human granulocyte colony-stimulating factor (rhG-CSF),blood products, or erythropoietin (EPO) within 14 days prior to enrollment.

9. Biochemical Criteria (within 1 week prior to enrollment)

Normal blood biochemistry (CTCAE v5.0 ≤ Grade 1, based on institutional laboratory standards):

Total bilirubin (TBIL) ≤ 1.5 × upper limit of normal (ULN). Alanine aminotransferase (ALT) ≤ 1.5 × ULN. Aspartate aminotransferase (AST) ≤ 1.5 × ULN. Alkaline phosphatase (ALP) ≤ 2.5 × ULN. Creatinine clearance (Ccr) ≥ 50 mL/min. Contraception Requirements Fertile patients must agree to use highly effective contraception (hormonal, barrier methods, or abstinence) with their partners during the trial and for at least 6 months after the last dose. Premenopausal female patients must have a negative blood or urine pregnancy test before enrollment.

Exclusion Criteria:

1. Stage IV metastatic breast cancer.

2. Bilateral breast cancer.

3. History of other malignancies within the past 5 years, except for cured basal cellcarcinoma of the skin, cervical carcinoma in situ, or papillary thyroid carcinoma.

4. Radiotherapy within 2 weeks prior to the first dose of the study drug.

5. Surgery within 2 weeks prior to the first dose of the study drug.

6. Prior treatment with utidelone or capecitabine, known hypersensitivity to utidelone,capecitabine, or fluoropyrimidines, or confirmed dihydropyrimidine dehydrogenase (DPD) deficiency.

7. Prior adverse reactions to anticancer therapy have not recovered to CTCAE v5.0 Grade ≤1 (excluding toxicities deemed non-risky by the investigator, such as alopecia).

8. Gastrointestinal disorders (e.g., esophageal obstruction, pyloric obstruction,intestinal obstruction), post-gastrointestinal resection, or other factors causingdysphagia that may interfere with oral drug absorption.

9. Severe comorbidities, including significant cardiac/cerebrovascular disease,uncontrolled diabetes/hypertension, active infections, or active peptic ulcer.

10. Active hepatitis B virus (HBV) infection.

11. History of immunodeficiency (e.g., HIV-positive status, congenital/acquiredimmunodeficiency disorders) or organ transplantation.

12. Psychiatric disorders or poor compliance.

13. Pregnancy (positive pregnancy test) or lactation.

14. Concurrent participation in another interventional clinical study or receiving otherinvestigational therapies.

15. Concomitant use of potent CYP3A4 inhibitors/inducers or QT-prolonging drugs within 14 days prior to the first dose or during the study.

16. Other conditions deemed unsuitable for study participation by the investigator.