Neoadjuvant Treatment of Triple-Negative Breast Cancer with Stereotactic Radiotherapy, PD-1 Monoclonal Antibody, and Chemotherapy

Chinese Academy of Medical Sciences & Peking Union Medical College

Status and phase: Not yet enrolling; Phase 2

Conditions: Breast Cancer Invasive

Treatments: Radiation: neoadjuvant SBRT combined with PD-1 monoclonal antibody and chemotherapy

Study type: Interventional

Funder types: Other

Identifiers

NCT06691594

NCC4456

Details and patient eligibility

About

The primary aim is to evaluate the efficacy of neoadjuvant SBRT combined with PD-1 monoclonal antibody and chemotherapy in patients with triple-negative breast cancer, with the endpoint being the pCR rate-defined as the proportion of patients with no residual invasive cancer in the breast and no axillary lymph node metastasis after treatment. This is a single-arm study. Eligible participants will receive : neoadjuvant treatment consisting of SBRT followed by Envafolimab (PD-1 inhibitor), chemotherapy and immunotherapy (Envafolimab). Surgery will be performed after the last chemotherapy cycle. Pathological evaluation will assess the treatment response. Patients will receive adjuvant immunotherapy (Envafolimab) up to 1 year post-surgery.

Enrollment: 20 estimated patients

Sex: Female

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

Signed written informed consent prior to enrollment Age ≥ 18 years ECOG PS score 0-1 Newly diagnosed T1c N1-2 or T2-3 N0-2 breast cancer Triple-negative breast cancer with PD-L1 CPS < 10 Hemoglobin ≥ 10.0 g/dl, Neutrophils ≥ 1.5 × 10⁹/L, Platelet count ≥ 100 × 10⁹/L; BUN ≤ 1.5 × upper limit of normal (ULN), Cr≤ 1.5 × ULN; Serum bilirubin ≤ 1.5 × ULN, AKP, AST, and ALT ≤ 2.5 × ULN Women of childbearing potential must be willing to use contraception during the study: Negative serum or urine pregnancy test within 7 days prior to treatment

Exclusion criteria

Occult breast cancer Bilateral breast cancer The breast tumor is unsuitable for SBRT Unable to undergo MRI scanning Has other malignancies that may affect survival time Has any active autoimmune disease or a history of autoimmune disease Currently using immunosuppressants or systemic steroids for immunosuppressive purposes, and has been using them within 2 weeks prior to enrollment Known allergy to any component of the investigational drugs Has uncontrolled cardiac symptoms or diseases Has an active infection or has unexplained fever > 38.5°C during screening or before the first dose Has other factors that may cause early termination of the study, such as other serious diseases requiring concurrent treatment, significant laboratory abnormalities, or factors related to family or social circumstances that could affect the patient's safety or data and sample collection

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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20 participants in 1 patient group

neoadjuvant SBRT combined with PD-1 monoclonal antibody and chemotherapy

Experimental group

Description:

Eligible participants will receive neoadjuvant treatment consisting of: SBRT: One session of 10Gy radiation to the primary tumor, followed by a 150mg subcutaneous injection of pembrolizumab (PD-1 inhibitor). Chemotherapy and Immunotherapy: One week after SBRT, participants will undergo 6 cycles of pembrolizumab (400mg), albumin-bound paclitaxel (250mg/m²), and carboplatin (AUC=5). Surgery: Surgery will be performed 21 days after the last chemotherapy cycle, with either breast-conserving surgery or modified radical mastectomy. Pathological evaluation will assess the treatment response. Adjuvant Immunotherapy: Four weeks post-surgery, patients will receive pembrolizumab every 3 weeks for up to 1 year.

Treatment:

Radiation: neoadjuvant SBRT combined with PD-1 monoclonal antibody and chemotherapy