Focused Ultrasound and Pembrolizumab in Metastatic Breast Cancer (Breast-48)

January 21, 2026 updated by: Patrick Dillon, MD

Focused Ultrasound Therapy to Augment Antigen Presentation and Immune-Specificity of Checkpoint Inhibitor Therapy With Pembrolizumab in Metastatic Breast Cancer

This pilot study evaluates the use of high-intensity focused ultrasound (HIFU) combined with pembrolizumab in patients with metastatic breast cancer. One-half of participants will be randomized to receive the first dose of pembrolizumab after HIFU and one-half of participants will be randomized to receive their first dose of pembrolizumab before HIFU.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Terminated

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
13

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 1

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

  • United States
    • Virginia
      • Charlottesville, Virginia, United States, 22908
        • University of Virginia

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

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria (summary):

  • Histologically confirmed metastatic or unresectable breast cancer
  • Any receptor status (estrogen receptor, progesterone receptor, HER2 receptor). Patients who are HR+ should also no longer be candidates for hormonal-based therapy. Patients who are HER2+ should have progressed on or no longer be candidates for available HER2 directed therapy. Hormonal therapy must be stopped prior to day 1 of treatment.
  • Patients must have had at least one prior line of therapy for breast cancer in the metastatic setting.
  • Patients must have an accessible lesion in the breast/chest wall/axilla which has not been previously thermally ablated. Prior breast irradiation is acceptable if the lesion has recurred or grown following radiation.
  • Patients must agree to use an adequate method of contraception for the course of the study through 120 days after the last dose of study medication.
  • Patients must have at least one target lesion in breast/chest wall/axilla which is amenable to application of high intensity focused ultrasound:
  • Patients must be willing to provide tissue from a newly obtained core or excisional biopsy of a tumor lesion.
  • Performance status of 0 or 1 on the ECOG Performance Scale.
  • Adequate organ function

Exclusion Criteria (summary):

  • Patients currently participating and receiving study therapy or patients who have participated in a study of an investigational agent and received study therapy or used an investigational device within 4 weeks of the first dose of treatment.
  • Patients with a diagnosis of immunodeficiency, patients receiving systemic steroid therapy or, patients who have received any other form of immunosuppressive therapy within 7 days prior to the first dose of trial treatment.
  • Patients with a known history of active Tuberculosis
  • Hypersensitivity to pembrolizumab or any of its excipients
  • Prior anti-cancer monoclonal antibody (mAb) within 4 weeks prior to study Day 1. Patients who have not recovered (i.e., ≤ Grade 1 or at baseline) from adverse events due to agents administered more than 4 weeks earlier are excluded.
  • Prior chemotherapy, targeted small molecule therapy, or radiation therapy within 2 weeks prior to study Day 1. Patients who has not recovered (i.e., ≤ Grade 1 or at baseline) from adverse events due to a previously administered agent.
  • Known additional malignancy that is progressing or requires active treatment. Exceptions include basal cell carcinoma of the skin or squamous cell carcinoma of the skin that has undergone potentially curative therapy or in situ cervical cancer.
  • Known active central nervous system (CNS) metastases and/or carcinomatous meningitis.
  • Active autoimmune disease that has required systemic treatment in the past 2 years.
  • History of (non-infectious) pneumonitis that required steroids or current pneumonitis.
  • Active infection requiring systemic therapy.
  • Pregnancy
  • Prior therapy with an anti-PD-1, anti-PD-L1, or anti-PD-L2 agent within the prior 24 weeks.
  • Known history of Human Immunodeficiency Virus (HIV)
  • Receipt of a live vaccine within 30 days of planned start of study therapy.
  • HIFU must not be applied to a breast with an implant. A region outside of the breast may be targeted as long as the targeted area is at least 10mm away from an implant.

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

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Arm A: 1st dose of pembrolizumab after HIFU
Pembrolizumab (200 mg) administered intravenously, days 22, 43, 64, followed by day 1 of each ensuing 3 -week cycle. Focused ultrasound tumor ablation day 15. High-intensity focused ultrasound ablation will target 50% of the tumor, up to 3 cubic centimeters.
Drug: Pembrolizumab
Pembrolizumab (200 mg)
Other Names:
  • Keytruda
Device: High-intensity focused ultrasound (HIFU)
Ablation will target 50% of the tumor, up to 3 cubic centimeters
Experimental: Arm B: 1st dose of pembrolizumab before HIFU
Pembrolizumab (200 mg) intravenously, days 1, 22, 43, 64, followed by day 1 of each ensuing 3 -week cycle. Focused ultrasound tumor ablation day 15. High-intensity focused ultrasound ablation will target 50% of the tumor, up to 3 cubic centimeters.
Drug: Pembrolizumab
Pembrolizumab (200 mg)
Other Names:
  • Keytruda
Device: High-intensity focused ultrasound (HIFU)
Ablation will target 50% of the tumor, up to 3 cubic centimeters

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Change in Proportion of CD8+ Tumor Infiltrating Lymphocytes
Time Frame: baseline and week 4
How many of the immune cells inside a tumor are a specific type of "killer" T cell
baseline and week 4

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Adverse event profile of pembrolizumab and HIFU
Time Frame: From date of randomization through 30 days following cessation of treatment
Toxicities from the combination of pembrolizumab and HIFU
From date of randomization through 30 days following cessation of treatment

Collaborators and Investigators

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

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Patrick Dillon, MD

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Patrick Dillon, MD, University of Virginia

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.

General Publications

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)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
September 25, 2017

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
June 1, 2022

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
June 17, 2022

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
July 31, 2017

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
July 31, 2017

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
August 2, 2017

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
February 9, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
January 21, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
January 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 19900

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

Yes

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

Clinical Trials on Pembrolizumab

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings