First-Line Dual Versus Single HER2-Targeted Therapy With Docetaxel for Advanced HER2-Positive Breast Cancer

NCT07829900 | Completed

• 1 other identifier: NMU-HER2BC-RWE-001
• Study Type: observational
• Target: 2,250
• Locations: 1 country
• Sites: 1

Brief Summary

This retrospective observational cohort study emulates a target trial to compare the effectiveness and safety of two first-line treatment strategies for women with HER2-positive unresectable locally advanced, recurrent, or metastatic breast cancer in routine clinical practice: pertuzumab plus trastuzumab and docetaxel versus trastuzumab and docetaxel. Data were obtained from electronic health records held by the National Health and Medical Big Data (Eastern) Center and linked with the Jiangsu Provincial Mortality Registry. Eligible patients initiated one of the two treatment strategies between January 1, 2020, and December 31, 2024. Time zero was defined as the date of the first administration of the qualifying first-line regimen. No minimum number of treatment cycles was required. The primary outcome was overall survival. Secondary outcomes included progression-free survival and prespecified adverse events.

Conditions

HER2-Positive Breast Cancer; Advanced Breast Cancer

Keywords

Pertuzumab; Trastuzumab; Docetaxel; Dual HER2-Targeted Therapy; Real-World Evidence; Target Trial Emulation

Outcome Measures

Primary Outcomes (1)

• Overall Survival (OS)

  Overall survival was defined as the time from the first administration of the index first-line treatment regimen to death from any cause.

  From the index date until death, last known follow-up, or December 31, 2024, whichever occurred first (up to 60 months)

Secondary Outcomes (2)

• Real-World Progression-Free Survival (rwPFS)

  From the index date until documented real-world disease progression, death, last known progression-free follow-up, or December 31, 2024, whichever occurred first (up to 60 months)

• Proportion of Participants With Prespecified Grade 3 or Higher Adverse Events

  From the index date through the documented end of first-line treatment (up to 60 months)

Study Arms (2)

Pertuzumab Plus Trastuzumab and Docetaxel

Drug: Pertuzumab; Drug: Trastuzumab; Drug: Docetaxel

Trastuzumab and Docetaxel

Drug: Pertuzumab; Drug: Docetaxel

Interventions

Pertuzumab DRUG

Pertuzumab administered as part of first-line dual HER2-targeted therapy with trastuzumab and docetaxel. Exposure was identified from electronic prescriptions, medication orders, and administration records.

Pertuzumab Plus Trastuzumab and Docetaxel; Trastuzumab and Docetaxel

Trastuzumab DRUG

Trastuzumab administered as part of first-line HER2-targeted therapy with docetaxel, with or without pertuzumab. Exposure was identified from electronic prescriptions, medication orders, and administration records.

Pertuzumab Plus Trastuzumab and Docetaxel

Docetaxel DRUG

Docetaxel administered as first-line chemotherapy in combination with HER2-targeted therapy. Exposure was identified from electronic prescriptions, medication orders, and administration records.

Pertuzumab Plus Trastuzumab and Docetaxel; Trastuzumab and Docetaxel

Eligibility Criteria

• Age: 18 Years+
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The study population comprised adult female patients with HER2-positive unresectable locally advanced, recurrent, or metastatic breast cancer who initiated first-line treatment with either pertuzumab plus trastuzumab plus docetaxel or trastuzumab plus docetaxel between January 1, 2020 and December 31, 2024. Eligible patients were retrospectively identified from the National Health and Medical Big Data (Eastern) Center. Electronic health record data were linked to the Jiangsu mortality registry. The index date (time zero) was defined as the date of the first administration of the index treatment regimen. Patients meeting the prespecified eligibility criteria during the study period were included.

You may qualify if:

• Female patients aged 18 years or older on the index date.
• Histologically or cytologically confirmed breast cancer.
• HER2-positive disease, defined according to available pathology records as immunohistochemistry (IHC) 3+ or IHC 2+ with positive in situ hybridization.
• Unresectable locally advanced, recurrent, or metastatic breast cancer on the index date.
• No prior systemic anticancer therapy for unresectable locally advanced, recurrent, or metastatic breast cancer before the index date.
• Initiation of first-line treatment with either:
• pertuzumab plus trastuzumab plus docetaxel; or
• trastuzumab plus docetaxel between January 1, 2020 and December 31, 2024.
• Sufficient information available on or before the index date to determine eligibility, treatment assignment, and baseline covariates.

You may not qualify if:

• Early-stage or resectable breast cancer treated with curative intent on the index date.
• Prior systemic anticancer therapy for unresectable locally advanced, recurrent, or metastatic breast cancer before the index date.
• Another active primary malignant tumor on the index date that was expected to materially affect survival.
• Insufficient or invalid information to determine HER2 status, advanced disease status, index treatment regimen, or index date.
• Absence of a valid patient identifier required for linkage between the electronic health record database and the mortality registry.

Sponsors & Collaborators

• Xin Li: lead

Study Sites (1)

Nanjing Medical University

Nanjing, Jiangsu, 2111166, China

Location

MeSH Terms

Interventions

pertuzumab; Trastuzumab; Docetaxel

Intervention Hierarchy (Ancestors)

Antibodies, Monoclonal, Humanized; Antibodies, Monoclonal; Antibodies; Immunoglobulins; Immunoproteins; Blood Proteins; Proteins; Amino Acids, Peptides, and Proteins; Serum Globulins; Globulins; Taxoids; Cyclodecanes; Cycloparaffins; Hydrocarbons, Alicyclic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals; Diterpenes; Terpenes

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Professor,PhD,PhD supervisor,Deputy Dean of the School of Pharmacy,Nanjing Medical University

Study Record Dates

• First Submitted: September 14, 2026
• First Posted: September 21, 2026
• Study Start: April 20, 2020
• Primary Completion: December 31, 2024
• Study Completion: December 31, 2024
• Last Updated: September 21, 2026

Record last verified: 2026-08

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)