Trastuzumab Plus Taxane Neoadjuvant Therapy for HER2-Positive Breast Ductal Carcinoma In Situ (DCIS) : A Phase II Study

Trastuzumab Combined With Taxane Neoadjuvant Therapy for HER2-positive Breast Carcinoma in Situ: a Phase II Single-arm Clinical Study

This is a phase II single-center single-arm clinical study designed to analyze the efficacy and safety of trastuzumab combined with taxane neoadjuvant therapy for HER2-positive breast carcinoma in situ (or with invasive carcinoma).

Study Overview

• Status: Enrolling by invitation
• Conditions: Breast Carcinoma in Situ
• Intervention / Treatment: Drug: Trastuzumab combined with taxane neoadjuvant therapy

Detailed Description

This Phase II single-center, single-arm clinical study was designed to evaluate the efficacy and safety of trastuzumab combined with taxane as a neoadjuvant treatment for patients with HER2-positive breast cancer in situ or invasive breast cancer. The study was designed to determine breast-conserving surgery rates and pathologic complete response (pCR) rates, assess tumor size reduction, and evaluate potential adverse events associated with treatment options. Participants will be treated with trastuzumab and taxane on a prescribed schedule, with periodic evaluations including imaging, histopathological analysis, and safety monitoring. The aim is to gain insight into the therapeutic potential of this combination therapy in improving outcomes for patients with HER2-positive breast cancer.

• Study Type: Interventional
• Enrollment (Estimated): 54
• Phase: Phase 2

Contacts and Locations

Study Locations

• China
  • Guangdong
    • Guangzhou, Guangdong, China
      • Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Diagnosed breast carcinoma in situ (female, 18 to 70 years old);
2. Breast mass ≥2cm, and in situ cancer pathology confirmed HER2 positive (definition: immunohistochemical results 3+ or in situ hybridization results positive);
3. No evidence of distant transfer;
4. Have not received any previous cancer treatment;
5. Imaging examination showed at least one measurable lesion within 2 weeks before enrollment;
6. Left ventricular ejection fraction (LVEF) was measured by echocardiography ≥50%;
7. Previous treatment-related toxicity should be alleviated to NCI CTCAE (version 5.0) ≤1 degree, AST and ALT≤2.5 times the upper limit of normal, total bilirubin ≤1.5 times the upper limit of normal;

8. Liver and kidney function tests are basically normal:

   1. Total bilirubin (TBIL) ≤3× upper limit of normal (ULN),
   2. Alanine aminotransferase and aspartate aminotransferase (ALT/AST) ≤2.5×ULN (patients with liver metastasis ≤5xULN),
   3. Serum creatinine ≤1.5×ULN or creatinine clearance (Ccr) ≥60 ml/min;

9. Adequate bone marrow functional reserve:

   1. White blood cell count (WBC) ≥3.0×10^9 / L,
   2. Neutrophil count (ANC) ≥1.5×10^9 / L,
   3. Platelet count (PLT) ≥70×10^9 / L
10. Fertile women must use contraceptives;
11. Be able to understand the research process, voluntarily participate in the study, and sign the informed consent.

Exclusion Criteria:

1. Metastatic breast cancer (stage IV);
2. History of invasive breast cancer, or prior systemic treatment to treat or prevent breast cancer;
3. Previous or concurrent malignant diseases, except skin basal cell carcinoma or cervical cancer in situ;
4. Patients with severe heart disease or discomfort that is not expected to tolerate chemotherapy, including but not limited to: fatal arrhythmias or higher grade atrioventricular block, unstable angina pectoris, clinically significant valvular disease, transmural myocardial infarction shown by electrocardiogram, uncontrolled hypertension;
5. Insufficient bone marrow or kidney function, liver function impairment;
6. Grade 2 or more severe peripheral neuropathy;
7. Patients with thrombocytopenia, neutropenia, anemia, hypokalemia, and elevation of alanine aminotransferase or aspartate aminotransferase above CTCAE Level 1;
8. Patients who are known to be allergic to the active ingredient or other ingredient of the investigational drug;
9. Had received radiotherapy, chemotherapy, endocrine therapy, or was participating in any interventional drug clinical trial within 4 weeks prior to enrollment;
10. Pregnant or lactating women, women of childbearing age who refused to use effective contraception during the study period;
11. Any other conditions that the investigator considers the patient unfit to participate in the study, concomitant diseases or conditions that may interfere with study participation, or any serious medical disorder that may affect the safety of the subject (e.g., uncontrolled heart disease, high blood pressure, active or uncontrollable infection, active hepatitis B virus infection).

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: treatment; The study includes a single treatment arm where all participants will receive a combination of trastuzumab and taxane as part of the neoadjuvant therapy. This treatment arm is designed to assess the efficacy and safety of the regimen in patients with HER2-positive breast carcinoma in situ; Trastuzumab (HER2-Targeted Therapy):Trastuzumab will be administered intravenously at a standard dosage based on the patient's body weight. The initial dose will be a loading dose followed by maintenance doses every three weeks, as per clinical guidelines for HER2-positive breast cancer treatment.The therapy targets the HER2 receptor to inhibit tumor growth and improve response rates.; Taxane (Chemotherapy):A taxane-based chemotherapeutic agent (e.g., paclitaxel or docetaxel) will be administered intravenously. The specific agent, dosage, and schedule will follow standard protocols used in the neoadjuvant setting for HER2-positive breast cancer.Taxanes work by disrupting microt

Drug: Trastuzumab combined with taxane neoadjuvant therapy; Trastuzumab combined with taxane neoadjuvant therapy

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Breast-conserving surgery rate after 4-6 cycles of treatment	The breast-conserving surgery rate was calculated as a percentage of the total number of patients who successfully completed breast-conserving surgery after neoadjuvant therapy. For this study, all patients were required to confirm after treatment that the tumor was resectable and had no significant metastasis by imaging evaluation, such as breast ultrasound or MRI.	From the start of neoadjuvant therapy to the completion of surgery (approximately 3-4 months after enrollment)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
pathological Complete Response (pCR)	pCR refers to the situation in which a patient's carcinoma in situ tumor has completely disappeared through pathological examination after neoadjuvant therapy. Measurement Tool: Histopathological examination of surgical specimens.	Within 3-4 months from enrollment, at the completion of neoadjuvant therapy.
Objective Response Rate (ORR)	ORR is the proportion of patients whose tumors have shrunk significantly over the course of treatment. Specifically, ORR includes both partial response (PR) and complete response (CR). Partial response (PR) : The maximum diameter or volume of the tumor is reduced by at least 30%, but it does not completely disappear. Complete response (CR) : The tumor disappears completely and no visible signs of cancer are confirmed by imaging tests, such as CT scans, MRI, or ultrasound. Measurement Tool: Imaging assessments (MRI, CT, or ultrasound).	Within 3-4 months from enrollment, at the completion of neoadjuvant therapy.
Overall survival	Measurement Tool: Survival status verified through medical records and patient follow-up.	From enrollment to 60 months ± 3 months or until the date of death from any cause, whichever occurs first.
Biomarker analysis o f HER2 and Ki-67 using immunohistochemistry (IHC) or quantitative PCR	Measurement Tool: Expression levels of specific biomarkers, such as HER2 and Ki-67, will be assessed using immunohistochemistry (IHC) or quantitative PCR, with tumor tissue or blood samples collected at baseline and post-therapy.	Within 4-6 months from enrollment, at the completion of surgery.
AE rate	Adverse event rate	From enrollment to 12 months after the end of study treatment.
Assessment of quality of life in patients using the FACT-B scale	Quality of life refers to people's perception and experience of their physical state, mental function, social ability, and overall personal situation based on socioeconomic, cultural background and value orientation. FACT-B scale was used to assess patients before treatment, during treatment (from the first day of the third cycle, and every two cycles thereafter), and 30 days after treatment. Patients' quality of life was quantified by the proportion of changes in the score	From enrollment to 12 months after the end of study treatment or the last follow-up visit.
Event-free survival (EFS) of 3 years	Event-free survival (EFS) is defined as the time from the initiation of neoadjuvant therapy to the first occurrence of disease progression, recurrence, second primary cancer, or death from any cause. In this study, 3-year EFS is defined as the proportion of patients who have not experienced any of these events within 36 months after starting treatment. Measurement Tool: Clinical and imaging follow-ups, verified by medical records.	At 36 months from the date of enrollment.
Event-free survival (EFS) of 5 years	Measurement Tool: Clinical and imaging follow-ups, verified by medical records.	At 60 months from the date of enrollment.

Collaborators and Investigators

• Sponsor: Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University
• Collaborators: Peking University Shenzhen Hospital

Study record dates

Study Major Dates

• Study Start (Actual): March 1, 2025
• Primary Completion (Estimated): January 1, 2027
• Study Completion (Estimated): January 1, 2030

Study Registration Dates

• First Submitted: December 26, 2024
• First Submitted That Met QC Criteria: February 24, 2025
• First Posted (Actual): February 25, 2025

Study Record Updates

• Last Update Posted (Actual): November 28, 2025
• Last Update Submitted That Met QC Criteria: November 23, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Neoplasms by Histologic Type; Neoplasms, Glandular and Epithelial; Skin Diseases; Breast Diseases; Carcinoma; Breast Neoplasms; Carcinoma in Situ; Skin and Connective Tissue Diseases; Breast Carcinoma In Situ; Antineoplastic Agents, Immunological; Antineoplastic Agents; Trastuzumab; Taxane
• Other Study ID Numbers: SYSKY-2024-746-01

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