Neoadjuvant adebrelimab plus chemotherapy for high-risk ER-positive/HER2-negative breast cancer

An Open-label, One-arm Phase II Study of Adebrelimab Combined With Neoadjuvant Chemotherapy for High-risk, Early-stage and Locally Advanced Estrogen Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative (ER+/HER2-) Breast Cancer.

This trial will test whether adding adebrelimab, an anti–PD‑L1 drug, to standard neoadjuvant chemotherapy helps people with early or locally advanced high‑risk ER‑positive/HER2‑negative breast cancer achieve a complete tumor response before surgery.

Quick facts

• Phase: Phase 2
• Study type: Interventional
• Enrollment: 48 (estimated)
• Ages: 18 Years to 65 Years
• Sex: Female
• Sponsor: Shanghai Jiao Tong University School of Medicine (Academic / other)
• Drugs / interventions: immunotherapy, adebelimab, chemotherapy
• Locations: 1 site (Shanghai, Shanghai Municipality)
• Trial ID: NCT06500208 on ClinicalTrials.gov

What this trial studies

This is a single-arm Phase 2 neoadjuvant trial combining adebrelimab with nab‑paclitaxel followed by epirubicin and cyclophosphamide in patients with early or locally advanced high‑risk ER+/HER2− breast cancer. Eligible participants must have measurable unilateral disease, provide core biopsy tissue for PD‑L1 and biomarker testing, and have ECOG 0–1 with adequate organ function. The primary objective is to increase pathologic complete response (pCR) rates at surgery while characterizing safety, and secondary analyses will explore biomarkers associated with response. All treatment and surgical care are planned at Ruijin Hospital in Shanghai.

Who should consider this trial

Good fit: Ideal candidates are adults with unilateral, high‑risk early or locally advanced ER+/HER2− breast cancer (for example grade 3 or high Ki‑67, node‑positive or larger tumors), measurable disease, available biopsy tissue, ECOG 0–1, and adequate hematologic, liver, renal and cardiac function.

Not a fit: Patients with bilateral disease, metastatic (stage IV) cancer, active autoimmune disease, recent systemic immunosuppression, severe cardiac disease, or who are pregnant or breastfeeding are unlikely to benefit or are ineligible.

Why it matters

Potential benefit: If successful, the combination could increase pathologic complete response rates before surgery and help define a role for immunotherapy in ER+/HER2− breast cancer.

How similar studies have performed: Checkpoint inhibitors plus chemotherapy have shown benefit mainly in triple‑negative breast cancer, while use in ER+/HER2− disease remains exploratory with limited positive data to date.

Eligibility criteria

Inclusion Criteria:

* pathologically diagnosed as unilateral primary invasive breast cancer with a) cT1c-T2N1-3 or cT3-4N0-3, b) Tumor Grade 3 or Grade 2 with PR- or Ki67 \> 20%;
* IHC ER expression ≥1%; IHC HER2 0 or 1+; IHC HER2 2+ and no amplification in FISH test;
* At least one measurable lesion according to RECIST 1.1;
* Available core needle biopsy samples for PD-L1 status testing;
* ECOG 0 or 1 within 10 days prior to initiation of treatment;
* Not currently pregnant or breastfeeding, agree to strict contraception during treatment and at least 6 months after last dose;
* Intact hematologic, liver, renal and heart functions;
* Signed written informed consent.

Exclusion Criteria:

* Bilateral invasive breast cancer or Stage IV breast cancer;
* Severe heart disease;
* Diagnosed as immune deficiency or receiving systemic steroid therapy or any form of immuno-suppressive therapy within 7 days prior to the first dose of treatment;
* Had active autoimmune diseases requiring systemic therapy within the past 2 years;
* Severe systemic infections or other serious medical conditions;
* Other malignant tumors in the past 5 years, except for cured carcinoma in situ of the cervix and skin cancer without melanoma;
* History of HIV infection;
* Active HBV or HCV infection;
* Known allergies or intolerance to the therapeutic drug or its excipients;
* History of application of any immunotherapy targeting PD-1/PD-L1/T cell receptors;
* Judged by the investigator to be unsuitable to participate in this study.

Where this trial is running

Shanghai, Shanghai Municipality

• Ruijin Hospital — Shanghai, Shanghai Municipality, China (Recruiting)

Study contacts

• Study coordinator: Haoyu Wang

Conditions Breast Cancer; breast cancer; ER+/HER2-; neoadjuvant; Adebrelimab