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

Prospective, Single-arm, Phase II Study of Stereotactic Radiotherapy Combined with PD-1 Monoclonal Antibody and Chemotherapy As Neoadjuvant Treatment for Triple-negative Breast Cancer

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.

Study Overview

• Status: Not yet recruiting
• Conditions: Breast Cancer Invasive
• Intervention / Treatment: Radiation: neoadjuvant SBRT combined with PD-1 monoclonal antibody and chemotherapy

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Xuran Zhao, Doctor; Phone Number: 13661135602; Email: 923791362@qq.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

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), creatinine ≤ 1.5 × ULN

Serum bilirubin ≤ 1.5 × ULN, alkaline phosphatase (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

Breast tumor unsuitable for SBRT

Unable to undergo MRI scanning

History of other malignancies that may affect survival

Active autoimmune disease or history of autoimmune disease

Current use of immunosuppressants or systemic steroids (within 2 weeks prior to enrollment)

Known allergy to any component of the investigational drugs

Uncontrolled cardiac symptoms or diseases

Active infection or unexplained fever > 38.5°C during screening/before first dose

Other factors likely to cause early study termination (e.g., serious concurrent illnesses, significant lab abnormalities, or social/family circumstances affecting safety/data collection)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: neoadjuvant SBRT combined with PD-1 monoclonal antibody and chemotherapy; 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.

Radiation: neoadjuvant SBRT combined with PD-1 monoclonal antibody and chemotherapy; 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.; Other Names: radiotherapy combined with chemotherapy and immunotherapy

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
the efficacy of neoadjuvant SBRT combined with PD-1 monoclonal antibody and chemotherapy	pCR rate-defined as the proportion of patients with no residual invasive cancer in the breast and no axillary lymph node metastasis after treatment	From enrollment to the completion of surgery

Collaborators and Investigators

• Sponsor: Cancer Institute and Hospital, Chinese Academy of Medical Sciences

Study record dates

Study Major Dates

• Study Start (Estimated): February 1, 2025
• Primary Completion (Estimated): November 1, 2028
• Study Completion (Estimated): November 1, 2030

Study Registration Dates

• First Submitted: November 14, 2024
• First Submitted That Met QC Criteria: November 14, 2024
• First Posted (Actual): November 15, 2024

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: February 18, 2025
• Last Verified: January 1, 2025

More Information

Terms related to this study

• Keywords: immunotherapy; triple-negative breast cancer; preoperative radiothrapy
• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Skin Diseases; Breast Diseases; Breast Neoplasms; Triple Negative Breast Neoplasms; Immunologic Factors; Physiological Effects of Drugs; Antibodies; Antibodies, Monoclonal
• Other Study ID Numbers: NCC4456

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No