HER2-low Unresectable and/or Metastatic Breast Cancer in Russia

March 11, 2026 updated by: AstraZeneca

A Multicenter Observational Retrospective Study of Therapeutic Approaches and Clinical Outcomes in Real Clinical Practice in Russian Patients With Human Epidermal Growth Factor Receptor 2 (HER2)-Low Unresectable and/or Metastatic Breast Cancer

Planned study population consists of approximately 3,150 adult patients with HER2-negative (IHC 0, + or IHC2+/ISH-) unresectable or metastatic BC enrolled to the study in order to obtain approximately 2,000 patients with confirmed HER2 low status (IHC1+ or IHC2+/ISH ).

Study Overview

Status

Completed

Conditions

Study Type

Observational

Enrollment (Actual)

1669

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Russia
      • Arkhangelsk, Russia
        • Research Site
      • Barnaul, Russia
        • Research Site
      • Belgorod, Russia
        • Research Site
      • Chelyabinsk, Russia
        • Research Site
      • Chita, Russia
        • Research Site
      • Grozny, Russia
        • Research Site
      • Irkutsk, Russia
        • Research Site
      • Istra, Russia
        • Research Site
      • Izhevsk, Russia
        • Research Site
      • Kaluga, Russia
        • Research Site
      • Kemerovo, Russia
        • Research Site
      • Khanty-Mansiysk, Russia
        • Research Site
      • Kirov, Russia
        • Research Site
      • Kostroma, Russia
        • Research Site
      • Krasnodar, Russia
        • Research Site
      • Krasnoyarsk, Russia
        • Research Site
      • Maykop, Russia
        • Research Site
      • Moscow, Russia
        • Research Site
      • Nal'chik, Russia
        • Research Site
      • Nizhny Novgorod, Russia
        • Research Site
      • Novosibirsk, Russia
        • Research Site
      • Omsk, Russia
        • Research Site
      • Orenburg, Russia
        • Research Site
      • Perm, Russia
        • Research Site
      • Pyatigorsk, Russia
        • Research Site
      • Ryazan, Russia
        • Research Site
      • Saint Petersburg, Russia
        • Research Site
      • Saransk, Russia
        • Research Site
      • Sevedorvinsk, Russia
        • Research Site
      • Smolensk, Russia
        • Research Site
      • Sochi, Russia
        • Research Site
      • Surgut, Russia
        • Research Site
      • Tomsk, Russia
        • Research Site
      • Tver', Russia
        • Research Site
      • Ufa, Russia
        • Research Site
      • Ulan-Ude, Russia
        • Research Site
      • Vladivostok, Russia
        • Research Site
      • Volgograd, Russia
        • Research Site
      • Yaroslavl, Russia
        • Research Site
      • Yuzhno-Sakhalinsk, Russia
        • Research Site

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Sampling Method

Non-Probability Sample

Study Population

Planned study population consists of approximately 3,150 adult patients with HER2-negative (IHC 0, + or IHC2+/ISH-) unresectable or metastatic BC enrolled to the study in order to obtain approximately 2,000 patients with confirmed HER2 low status (IHC1+ or IHC2+/ISH ).

Description

Inclusion Criteria:

  • Patients with confirmed diagnosis of unresectable and/or metastatic BC established between the 1st July 2021 and the 1st July 2022.

  • Patients have HER2-negative status (IHC0, IHC1+, IHC2+/ISH-) obtained in the local laboratory.

    -. Patients have an adequate archival tumor sample and slides suitable for reassessment HER2 status* by the reference laboratory.

  • Patients have documented hormonal status (ER, PR) IHC score.
  • Age ≥ 18 years at the time of inclusion.
  • Patients provided written consent allowing for data and samples to be used in the future and this study would be covered by the consent for future use in accordance with ICH GCP, GPP (Good Pharmacoepidemiology Practices) and local law prior to inclusion in the study. If the patient is deceased, a waiver may be accepted

Exclusion Criteria:

  • Patients with previous HER2 positive status in the anamnesis at the diagnosis or after the diagnosis of breast cancer.
  • Presence of other malignancies within period since diagnosis until the timepoint of data collection.
  • Patients receiving trastuzumab deruxtecan currently or received in anamnesis.
  • The participation in any randomised controlled trial within period since diagnosis until end of study.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
To study the overall prevalence of HER2-low among patients with HER2-negative mBC, based on reassessment of historical HER2 fixed tissue IHC stained slides assay in the Russian Federation
Time Frame: 12 months
12 months
To study the clinical-pathological, histopathological and demographic profiles of patients of HR-positive and HR-negative HER2-low status among unresectable and/or mBC patients identified as HER2-negative HR-positive/negative
Time Frame: 12 months
Clinical and demographic data, as well as other study variables will be presented as frequencies or percentages, or as the mean value, standard deviation, median, quantiles, minimum and maximum, depending on the type of variable (continuous or categorical) for the total sample and all subgroups (if applicable).
12 months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
To describe data on the diagnostic algorithms and therapeutic tactics in patients with HR-positive and HR-negative HER2-low unresectable and/or mBC in routine practice in the Russian Federation
Time Frame: 12 months
Data on methods used for diagnosis will be presented as frequencies or percentages, or as the mean value, standard deviation, median, quartiles, minimum and maximum, depending on the type of variable (categorical or continuous) for the total sample and all subgroups
12 months
To describe data on the treatment approach in patients with HR-positive and HR-negative HER2-low unresectable and/or mBC in routine practice in the Russian Federation, and the sequence of therapy administration (HR-positive and HR-negative).
Time Frame: 12 months
Data on methods used for anticancer and concomitant treatment will be presented as frequencies or percentages, or as the mean value, standard deviation, median, quartiles, minimum and maximum, depending on the type of variable (categorical or continuous) for the total sample and all subgroups
12 months
To assess the treatment outcomes of patients with HR-positive and HR-negative HER2-low unresectable and/or mBC in routine practice in the Russian Federation
Time Frame: 12 months
Data on methods used for anticancer and concomitant treatment will be presented as frequencies or percentages, or as the mean value, standard deviation, median, quartiles, minimum and maximum, depending on the type of variable (categorical or continuous) for the total sample and all subgroups
12 months
To characterize the concordance between HER2 IHC scores in local and reference laboratories after reassessment in the reference lab (IHC 0, 1+, 2+/ISH-) using the existing, and refined, criteria of ASCO/CAP definition
Time Frame: 12 months
The frequency of concordance of IHC HER2 scores and ISH results between local and reference laboratories will be calculated along with exact 95% CIs. Cohen's Kappa statistics will be used to evaluate concordance between HER2 IHC scores in local and reference laboratories.
12 months
To describe the concordance of HER2 status evaluations performed in a reference laboratory by a pathologist manually and by an artificial intelligence (AI) program.
Time Frame: 12 months
Concordance assessed using Cohen's Kappa statistics (positive, negative and overall agreement) between HER2 status evaluations performed in a reference laboratory by a pathologist manually and by an AI program.
12 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

AstraZeneca

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

May 30, 2023

Primary Completion (Actual)

March 14, 2025

Study Completion (Actual)

March 14, 2025

Study Registration Dates

First Submitted

May 30, 2023

First Submitted That Met QC Criteria

June 12, 2023

First Posted (Actual)

June 22, 2023

Study Record Updates

Last Update Posted (Actual)

March 12, 2026

Last Update Submitted That Met QC Criteria

March 11, 2026

Last Verified

March 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • D133HR00029

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

Qualified researchers can request access to anonymized individual patient-level data from AstraZeneca group of companies sponsored clinical trials via the request portal Vivli.org. All requests will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure. Yes, indicates that AZ are accepting requests for IPD, but this does not mean all requests will be shared.

IPD Sharing Time Frame

AstraZeneca will meet or exceed data availability as per the commitments made to the EFPIA PhRMA Data Sharing Principles. For details of our timelines, please rerefer to our disclosure commitment at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

IPD Sharing Access Criteria

When a request has been approved AstraZeneca will provide access to the anonymized individual patient-level data via secure research environment Vivli.org.

Signed Data Usage Agreement (non-negotiable contract for data accessors) must be in place before accessing requested information.

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Breast Cancer

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Switzerland

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe