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Active, not recruiting Phase 2 Interventional

Determinants of Resistance to Endocrine Therapy and a Cyclin-dependent Kinases 4 and 6 (CDK4/6) Inhibitor for HR+ MBC

ClinicalTrials.gov ID: NCT03439735

Public ClinicalTrials.gov record NCT03439735. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 7, 2026, 10:26 PM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

Prospective Evaluation of Determinants of Resistance to Endocrine Therapy and a Cyclin-dependent Kinases 4 and 6 (CDK4/6) Inhibitor in Hormone Receptor (HR) Positive Metastatic Breast Cancer (MBC)

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

The goal of this research study is to determine if the investigators can predict which participants will respond to endocrine therapy and a cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitor for metastatic breast cancer and which participants will not. Investigators will use information from the tumor tissue and serial blood samples. Investigators hope that a deeper understanding of which participants will respond to this combination and how resistance emerges will allow the investigators to better tailor therapies for metastatic breast cancer. Subjects will have archived tissue or new biopsy collected at study enrollment. This tissue will undergo special molecular testing. Subjects will also have blood collected at study enrollment and periodically thereafter. This blood will also undergo special molecular testing. Information from this testing will not be available to subjects or their treating physicians as the investigators do not know how this information should impact treatment. The investigators will collect information about which treatment the subjects receive and how their cancer responds. Any man or woman being seen at Johns Hopkins for treatment of newly diagnosed estrogen receptor positive (ER+) and/or progesterone receptor positive (PR+) metastatic breast cancer may be eligible.

Study identification

NCT ID
NCT03439735
Recruitment status
Active, not recruiting
Study type
Interventional
Phase
Phase 2
Enrollment
45 participants

Conditions and interventions

Eligibility (public fields only)

Age range
18 Years to 100 Years
Sex
All
Healthy volunteers
Healthy volunteers not accepted

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Jul 19, 2018
Primary completion
Jul 31, 2027
Completion
Oct 31, 2027
Last update posted
Aug 6, 2026

2018 – 2027

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
Johns Hopkins University Baltimore Maryland 21287

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT03439735, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Aug 6, 2026 · Synced Sep 7, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT03439735 live on ClinicalTrials.gov.

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