[18F]ISO-1 Positron Emission Tomography (PET/CT) in Primary Breast Cancer (ISO-1Primary)

January 7, 2026 updated by: University of Pennsylvania

Imaging of In Vivo Sigma-2 Receptor Expression With [18F]ISO-1 Positron Emission Tomography (PET/CT) in Primary Breast Cancer

In this study, positron emission tomography (PET/CT) imaging will be used to evaluate sigma-2 (σ2) receptor activity in sites of primary breast cancer using the investigational radiotracer [18F]ISO-1.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Active, not recruiting

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.

Detailed Description

This study will evaluate the feasibility of using [18F]ISO-1 PET/CT to image sigma-2 receptor binding in primary breast tumors and continue to evaluate the safety of the tracer in this patient population. [18F]ISO-1 uptake measures will be correlated with qualitative immunohistochemical staining for cell proliferation (Ki67). This is an observational study in that [18F]ISO-1 PET/CT will not be used to direct treatment decisions.

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 (Estimated)

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.
30

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
    • Pennsylvania
      • Philadelphia, Pennsylvania, United States, 19104
        • University of Pennsylvania Hospital

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:

  1. Adult patients, at least 18 years of age
  2. Known or suspected breast cancer with at least one breast lesion that is 1 cm or greater in size by standard imaging (e.g. mammography, ultrasound or breast MRI)
  3. Participants must be informed of the investigational nature of this study and provide written informed consent in accordance with institutional and federal guidelines prior to study-specific procedures

Exclusion Criteria:

  1. Females who are pregnant at the time of screening will not be eligible for this study, urine or serum pregnancy test will be performed in women of child-bearing potential at the time of screening.
  2. Inability to tolerate imaging procedure in the opinion of an investigator or treating physician
  3. Serious or unstable medical or psychological conditions that, in the opinion of the investigator, would compromise the subject's safety or successful participation in the study.
  4. Unwilling or unable to provide informed consent.

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: Diagnostic
  • Allocation: N/A
  • Interventional Model: Single Group 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: ISO-1 PET/CT
All subjects will receive an [18F]ISO-1 PET/CT scan
Drug: [18F]ISO-1
[18F]ISO-1 PET/CT scan
Other Names:
  • N-(4-(6,7-dimethoxy-3,-4-dihydroisoquinolin-2(1H)-yl)butyl)-2-(2-[18F]-fluoroethoxy)-5- Methylbenzamide ([18F]ISO-1)

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
Correlate [18F]ISO-1 uptake with pathologic assays measuring cellular proliferation rates (e.g. Ki-67)
Time Frame: 6 years
Correlate [18F]ISO-1 uptake with pathologic assays measuring cellular proliferation rates (e.g. Ki-67)
6 years

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
Evaluate the feasibility of using [18F]ISO-1 to image sigma-2 receptor binding in breast cancer
Time Frame: 6 years
Evaluate the feasibility of using [18F]ISO-1 to image sigma-2 receptor binding in breast cancer
6 years
Evaluate the safety of [18F]ISO-1
Time Frame: 6 years
Evaluate the safety of [18F]ISO-1
6 years
Correlate [18F]ISO-1 uptake with Autoradiography
Time Frame: 6 years
Correlate [18F]ISO-1 uptake with Autoradiography
6 years
Correlate [18F]ISO-1 uptake a with multi-gene expression assay, validated to predict recurrence
Time Frame: 6 years
Correlate [18F]ISO-1 uptake a with multi-gene expression assay, validated to predict recurrence
6 years
Correlate [18F]ISO-1 uptake with outcomes (e.g. time to recurrence, progression free survival and overall survival)
Time Frame: 6 years
Correlate [18F]ISO-1 uptake with outcomes (e.g. time to recurrence, progression free survival and overall survival)
6 years
Test the association of [18F]ISO-1 uptake with phenotypic breast cancer subtypes (e.g. HER2+, TN, ER/PR+, etc.)
Time Frame: 6 years
Test the association of [18F]ISO-1 uptake with phenotypic breast cancer subtypes (e.g. HER2+, TN, ER/PR+, etc.)
6 years

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.
University of Pennsylvania

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: David Mankoff, MD, PhD, University of Pennsylvania
  • Principal Investigator: Elizabeth McDonald, MD, PhD, University of Pennsylvania

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.
March 11, 2015

Primary Completion (Estimated)

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.
November 1, 2026

Study Completion (Estimated)

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.
November 1, 2026

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).
November 3, 2014

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.
November 3, 2014

First Posted (Estimated)

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.
November 6, 2014

Study Record Updates

Last Update Posted (Estimated)

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.
January 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 7, 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

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.
  • 820737

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.

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