Camrelizumab, Pirfenidone, and Chemotherapy in the Treatment of Advanced Triple-Negative Breast Cancer

Inclusion criteria

• Female, aged 18-70 years.
• Histologically confirmed recurrent/metastatic TNBC (ER-negative: IHC ER <1%; PR-negative: IHC PR <1%; HER2-negative: IHC -/+, or IHC ++ but FISH/CISH negative), with at least one measurable lesion per RECIST v1.1.
• ECOG performance status 0-2.
• Estimated life expectancy ≥3 months.
• Received first-line chemotherapy + PD-1/PD-L1 inhibitor for metastatic or locally advanced unresectable TNBC, with response of CR/PR or stable disease lasting ≥3 months. For neoadjuvant/adjuvant therapy, disease progression during treatment or within 6 months after completion will be considered as first-line failure.
• Adequate organ function (no transfusion, growth factor, or thrombopoietic agents within 2 weeks before screening):
• Hematology: ANC ≥1.5×10⁹/L; PLT ≥90×10⁹/L; Hb ≥90 g/L.
• Serum chemistry: TBIL ≤1.5×ULN; ALT and AST ≤1.5×ULN; ALP ≤2.5×ULN; BUN and Cr ≤1.5×ULN with creatinine clearance ≥50 mL/min (Cockcroft-Gault).
• TSH ≤ULN (if abnormal, T3 and T4 must be assessed; enrollment allowed if T3/T4 normal).
• Cardiac: LVEF ≥50% by echocardiography; 18-lead ECG with QTcF <480 ms (female).
• Women of childbearing potential must have negative pregnancy test (serum or urine) within 7 days prior to enrollment and agree to use adequate contraception during treatment and for 4 months after last dose.
• Voluntarily signed informed consent and good compliance.

Exclusion criteria

• Concurrent participation in another interventional cancer trial.
• Received other antitumor therapy within 14 days before first dose.
• Prior treatment with pirfenidone.
• Untreated active brain metastases or leptomeningeal disease.
• Major non-breast cancer surgery within 4 weeks prior to enrollment or incomplete recovery from such surgery.
• Active or history of autoimmune disease (except vitiligo, resolved childhood asthma without treatment in adulthood).
• Severe cardiac disease (e.g., heart failure with LVEF <50%, uncontrolled arrhythmias, angina requiring medication, significant valvular disease, recent myocardial infarction, poorly controlled hypertension >180/100 mmHg).
• Congenital or acquired immunodeficiency (e.g., HIV infection).
• Live vaccination within 4 weeks before or during study.
• Known allergy to study drugs or excipients.
• Severe concomitant disease or condition that may interfere with study participation per investigator judgment