A Prospective, Open-label, Single-arm, Exploratory Clinical Trial to Evaluate the Safety and Tolerability of 225Ac-TR2205 Injection in Patients With Triple-negative Breast Cancer.

January 6, 2026 updated by: Xiaorong Sun
This study is a prospective, single-center, single-arm, open-label research. It evaluates the safety and tolerability of 225Ac-TR2205 in patients with triple-negative breast cancer (TNBC), and assesses its radiation dosimetry and initial efficacy.

Study Overview

Status

Status

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

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.
15

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.
  • Early 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 Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

  • China
    • Shandong
      • Jinan, Shandong, China
        • Recruiting
        • Cancer Hospital of Shandong First Medical University

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

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  1. Voluntary participation in the study and signing of the informed consent form.
  2. Female patients aged 18 years and above.
  3. Patients with triple-negative breast cancer who have been diagnosed by histopathology [immune histochemistry estrogen receptor (ER) positive rate < 1% is defined as ER negative expression; progesterone receptor (PR) positive rate < 1% is defined as PR negative; human epidermal growth factor receptor 2 (HER2) expression 0-1+ or HER2 ++ but fluorescence in situ hybridization/colorimetric in situ hybridization (FISH/CISH) negative is defined as HER2 negative expression].
  4. Patients with metastatic triple-negative breast cancer who have received at least 2 systemic treatments (at least 1 of which is for metastatic disease).
  5. Patients with at least 1 measurable lesion (tumor evaluation according to RECIST 1.1).
  6. ECOG performance status assessment of 0-1.
  7. Clinical significance of hematological toxicity related to previous treatment must recover to ≤ 2 grade, and non-hematological toxicity ≤ 1 grade (except for hair loss).
  8. For patients with reproductive potential: 7 days before the first administration, fertile women must confirm that the urine pregnancy test is negative and agree to use effective contraceptive measures during the use of the study drug and within 6 months after the last administration (such as oral contraceptives, intrauterine devices, restraint of sexual desire or barrier contraception combined with spermicides, etc.).

Exclusion Criteria:

  1. Patients who received radiotherapy (except palliative radiotherapy) or chemotherapy, immunotherapy within 3 weeks before treatment, except for bisphosphonates (which can be used for bone metastasis), are excluded.
  2. Patients who received radionuclide therapy within 6 months before enrollment, such as strontium-89, samarium-153, rhenium-186, rhenium-188, radium-223, lutetium-177, actinium-225, or whole-body radiotherapy.
  3. Patients who are undergoing chemotherapy, immunotherapy, biological therapy, off-label radionuclide therapy, or other investigational treatments.
  4. Patients who have undergone major surgery within 28 days before enrollment.
  5. Patients evaluated by the investigator are expected to have a life expectancy of less than 3 months.
  6. Bone scans show super bone imaging, defined as uniform and significant concentration of radioactive isotopes in the entire skeleton relative to soft tissue, while the urinary system is not visible or shows mild visibility.
  7. Symptomatic spinal cord compression, or clinical or imaging evidence suggesting impending spinal cord compression.
  8. Patients with uncontrollable central nervous system (CNS) metastases, who need symptomatic treatment with glucocorticoids or mannitol, and if necessary, enhanced CT or MRI to clarify the status of brain metastases.
  9. Patients with a history of other malignant tumors, except for those with fully treated malignant tumors that have survived without treatment for more than 3 years without recurrence or progression, or patients with fully treated non-melanoma skin cancer and superficial bladder cancer.
  10. Patients with a history that may interfere with the purpose of the study and assessment, or the investigator determines that the patient has any condition that cannot cooperate with imaging examinations, treatment, and procedures.

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: 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: 225Ac-TR2205 Injection
Drug: 225Ac-TR2205 Injection
Patients will receive 225Ac-TR2205 injection administration at an interval of 8 weeks between each dose.

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
Time Frame
The incidence and severity grades of adverse events (AE), serious adverse events (SAE), and unexpected serious adverse reactions (SUSAR) were evaluated according to the CTCAE 5.0 standard.
Time Frame: 8 weeks after the last dose
8 weeks after the last dose

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.
Xiaorong Sun

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.
May 22, 2025

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.
April 1, 2027

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.
May 1, 2029

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).
January 6, 2026

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.
January 6, 2026

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.
January 14, 2026

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.
January 14, 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 6, 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

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.
  • TR2205-305

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

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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