Suspended

DISCORDANTTrastuzumab Deruxtecan vs CDK4/6 Inhibitors for HER2-low Metastatic Breast Cancer

What is being tested

Trastuzumab deruxtecan (T-DXd)

+ Ribociclib with ET

+ Abemaciclib with ET

Drug

Who is being recruted

Breast Diseases+3

+ Breast Neoplasms

+ Neoplasms

Over 18 Years

+9 Eligibility Criteria

See all eligibility criteria

How is the trial designed

Treatment Study

Phase 3

Interventional

Study Start: January 2026

See protocol details

Summary

Principal SponsorDanish Breast Cancer Cooperative Group

Last updated: February 13, 2026

Sourced from a government-validated database.Claim as a partner

Study start date: January 1, 2026

Actual date on which the first participant was enrolled.

This clinical trial is designed to compare two treatment options for patients with a specific type of metastatic breast cancer that is non-luminal A, ER-positive, and HER2-low. The study aims to evaluate the effectiveness of an investigational drug, trastuzumab deruxtecan, against the current standard treatment, which includes CDK4/6 inhibitors combined with endocrine therapy. This research is important because it could lead to improved treatment strategies for individuals with this type of breast cancer, potentially offering better outcomes and new hope for patients who are dealing with this challenging condition. Participants in this trial will be randomly assigned to receive either the investigational drug or the standard treatment. Trastuzumab deruxtecan is administered intravenously every 21 days, while the standard treatment involves taking a CDK4/6 inhibitor, with specific options determined by the treating physician, alongside daily endocrine therapy. The study will involve regular scans every 9-12 weeks to monitor the cancer's response to the treatment. Additional supportive care like anti-nausea medication and antibiotics is permitted, and the trial will document all treatments received. This careful monitoring will help assess how well each treatment works and any side effects that participants may experience.

Official TitleA Randomised Trial Comparing Trastuzumab Deruxtecan to CDK4/6 Inhibitors in Non-luminal A, ER-positive/HER2-low Metastatic Breast Cancer

NCT06585969

Principal SponsorDanish Breast Cancer Cooperative Group

Last updated: February 13, 2026

Sourced from a government-validated database.Claim as a partner

Protocol

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

Treatment Study

These studies test new ways to treat a disease, condition, or health issue. The goal is to see if a new drug, therapy, or approach works better or has fewer side effects than existing options.

Eligibility

Researchers look for people who fit a certain description, called eligibility criteria: person's general health condition or prior treatments.

Conditions

Criteria

Female

Biological sex of participants that are eligible to enroll.

Over 18 Years

Range of ages for which participants are eligible to join.

Healthy volunteers not allowed

If individuals who are healthy and do not have the condition being studied can participate.

Conditions

Pathology

Breast DiseasesBreast NeoplasmsNeoplasmsNeoplasms by SiteSkin DiseasesSkin and Connective Tissue Diseases

Criteria

6 inclusion criteria required to participate

Women aged 18 or above.

Radiologically/pathologically verified metastatic breast cancer.

ER-positive (1% or more) and HER2-low (HER2 1+ or HER2 2+/ISH-neg)10,11.

PAM50 Luminal B, HER2-enriched or Basal-like.

Show More Criteria

3 exclusion criteria prevent from participating

Patients who are incapable of understanding the written material received

Patients with inaccessible tumour tissue

Other malignant disease within 5 years (in situ cervix and non-melanoma skin cancer excluded)

Study Plan

Find out more about all the medication administered in this study, their detailed description and what they involve.

Treatment Groups

Study Objectives

2 intervention groups are designated in this study

This study does not include a placebo group

Treatment Groups

Group I

Experimental

Trastuzumab deruxtecan until progression or intolerable toxicity: 5.4 mg/kg intravenous on day 1 of a 21 days cycle.

Group II

Active Comparator

\- CDK4/6 inhibitor with an endocrine therapy until progression og intolerable toxicity * CDK4/6 inhibitor: Physician's choice of ribociclib (600mg daily for 21 days in a 4 week schedule) or abemaciclib (125mg twice daily). * Endocrine therapy: letrozole (2.5mg daily), anastrozole (1mg daily), exemestane (25mg daily), tamoxifen (20mg daily) or fulvestrant (intramuscular 500mg every 4 weeks)

Study Objectives

Primary Objectives

Secondary Objectives

Study Centers

These are the hospitals, clinics, or research facilities where the trial is being conducted. You can find the location closest to you and its status.

This study has no location dataSave this study to your profile to know when the location data is available.

SuspendedNo study centers