Molecular Imaging of EpCam Expression in Breast Cancer Using [99mTc]Tc-DARPinEc1-G3C (EpCam-Scan)

SPECT/CT Imaging of Epithelial Cell Adhesion Molecule (EpCam) Expression in Triple Negative and Luminal Breast Cancer Using Technicium-99m-labelled Designed Ankyrin Repeat Proteins Ec1-G3C ([99mTc]Tc-DARPinEc1-G3C)

The study should evaluate distribution of [99mTc]Tc-DARPinEc1-G3C in patients with primary Triple negative and Luminal breast cancer.

The primary objective are:

1. To assess distribution of [99mTc]Tc-DARPinEc1-G3C in normal tissues and in tumors over time;
2. To evaluate dosimetry of [99mTc]Tc-DARPinEc1-G3C in breast cancer patients;
3. To obtain initial information concerning safety and tolerability of [99mTc]Tc-DARPinEc1-G3C in breast cancer patients after single intravenous injection:

The secondary objective are:

1. To compare the tumour imaging data with [99mTc]Tc-DARPinEc1-G3C in breast cancer patients with Triple negative and Luminal subtypes.

Study Overview

• Status: Enrolling by invitation
• Conditions: Primary Breast Cancer
• Intervention / Treatment: Drug: [99mTc]Tc-DARPinEc1-G3C

Detailed Description

Overall goal of the project: To determine EpCam expression in primary breast cancer before any system therapy.

Phase I. Distribution of [99mTc]Tc-DARPinEc1-G3C in patients with primary breast cancer. The study should evaluate distribution of [99mTc]Tc-DARPinEc1-G3C in patients with primary Triple negative and Luminal breast cancer before treatment.

Methodology: Open-label, exploratory, single center study. The subjects will receive a single injection of the labelled tracer.

• Study Type: Interventional
• Enrollment (Estimated): 10
• Phase: Phase 1

Contacts and Locations

Study Locations

• Russia
  • Tomsk Reg
    • Tomsk, Tomsk Reg, Russia, 634050
      • Russia Tomsk NRMC

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Subject is > 18 years of age
2. Morphological verification of Breast Cancer T2-4N0-3M0-1
3. Negative HER2 expression in primary tumour tissue according ASCO/CAP 2023 recommendation
4. ECOG 0-2.
5. A negative pregnancy test for all patients of childbearing potential. Sexually active women of childbearing potential participating in the study must use a medically acceptable form of contraception for at least 30 days after study termination
6. Subject is capable to undergo the diagnostic investigations to be performed in the study
7. Informed consent

Exclusion Criteria:

1. Refusal from the study
2. Any system/local treatment
3. Second, non-breast malignancy
4. Active current autoimmune/infection disease or history of autoimmune disease. Known HIV positive or chronically active hepatitis B or C
5. Administration of other investigational medicinal product within 30 days of screening
6. Pregnancy
7. Ongoing toxicity > grade 2 from previous standard or investigational therapies, according to US National Cancer Institute's

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: One single injection of [99mTc]Tc-DARPinEc1-G3C; A single injected dose of 3000 µg of [99mTc]Tc-DARPinEc1-G3C will be evaluated. The study requires enrollment of at least five (5) evaluable subjects per pathology cohort (Triple negative breast cancer and Luminal breast cancer). Subjects withdrawn from the study for any reason will be replaced.	Drug: [99mTc]Tc-DARPinEc1-G3C; One single injection of [99mTc]Tc-DARPinEc1-G3C, followed by gamma camera imaging directly postinjection and after 2, 4, 6, 24 and 48 hours.; Other Names: SPECT

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
SPECT-based [99mTc]Tc-DARPinEc1-G3C uptake value in tumor lesions (counts)	[99mTc]Tc-DARPinEc1-G3C uptake coinciding with tumor lesions will be assessed using single-photon emission computed tomography and measured in counts.	6 hours
SPECT-based [99mTc]Tc-DARPinEc1-G3C background uptake value (counts)	Focal uptake of [99mTc]Tc-DARPinEc1-G3C in the regions without pathological findings will be assessed with SPECT and measured in counts	6 hours
Tumor-to-background ratio (SPECT)	The SPECT-based tumor-to-background ratio will be calculated as follows: the value of [99mTc]Tc-DARPinEc1-G3C uptake coinciding with tumor lesions (counts) will be divided by the value of [99mTc]Tc-DARPinEc1-G3C uptake coinciding with the regions without pathological findings (counts)	6 hours
Gamma camera-based whole-body [99mTc]Tc-DARPinEc1-G3C uptake value (percent)	Whole-body [99mTc]Tc-DARPinEc1-G3C uptake coinciding with normal organs and tissues will be assessed using gamma camera and calculated as percentage (%) of the injected dose of the radiopharmaceutical.	6 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent of cases with abnormal findings based on the assessments of physical examination relative to baseline	The safety attributable to [99mTc]Tc-DARPinEc1-G3C injections will be evaluated based on the assessments of physical examination (percent of cases with abnormal findings relative to baseline)	48 hours
Percent of cases with abnormal findings based on the assessments of vital signs relative to baseline	The safety attributable to [99mTc]Tc-DARPinEc1-G3C injections will be evaluated based on the assessments of vital signs (percent of cases with abnormal findings relative to baseline)	48 hours
Rate of adverse events (percent)	The safety attributable to [99mTc]Tc-DARPinEc1-G3C injections will be evaluated based on the rate of adverse events (percent)	48 hours
Rate of administration of concomitant medication (percent)	The safety attributable to [99mTc]Tc-DARPinEc1-G3C injections will be evaluated based on the rate of administration of concomitant medication (percent)	48 hours

Collaborators and Investigators

• Sponsor: Tomsk National Research Medical Center of the Russian Academy of Sciences
• Investigators: Principal Investigator: Vladimir I. Chernov, Cardiology Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences

Study record dates

Study Major Dates

• Study Start (Actual): June 22, 2026
• Primary Completion (Estimated): August 1, 2028
• Study Completion (Estimated): August 1, 2028

Study Registration Dates

• First Submitted: August 20, 2026
• First Submitted That Met QC Criteria: August 20, 2026
• First Posted (Actual): August 25, 2026

Study Record Updates

• Last Update Posted (Actual): August 26, 2026
• Last Update Submitted That Met QC Criteria: August 24, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Breast Cancer; EpCAm expression; [99mTc]Tc-DARPinEc1-G3C
• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Skin Diseases; Breast Diseases; Skin and Connective Tissue Diseases; Breast Neoplasms
• Other Study ID Numbers: ORI-2026.09.06

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No