A Phase 1 Study of 68Ga-R11228 and 177Lu-R11228 in Breast Cancer

NCT07121244 | Recruiting Phase 1 FDA Drug

• 1 other identifier: R11228-101
• Study Type: interventional
• Target: 62
• Locations: 2 countries
• Sites: 7

Brief Summary

A phase 1 study of 68Ga-R11228 and 177Lu-R11228 in breast cancer.

Conditions

Locoregionally Recurrent Hormone-receptor Positive Breast Cancer; Metastatic Hormone Receptor Positive Breast Cancer

Keywords

Hormone Receptor Positive Breast Cancer; Endocrine resistant; Radioisotope

Outcome Measures

Primary Outcomes (5)

• Incidence of adverse events [68Ga-R11228]

  Number of participants with adverse events as assessed by NCI-CTCAE v5.0, including grade

  Day 1 to Day 7

• Incidence of Serious Adverse Events [68Ga-R11228]

  Number of participants with serious adverse events

  Day 1 to Day 7

• Incidence of adverse events [177Lu-R11228]

  Number of participants with adverse events as assessed by NCI-CTCAE v5.0, including grade

  Day 1 to week 36

• Incidence of Serious Adverse Events [177Lu-R11228]

  Number of participants with serious adverse events

  Day 1 to week 36

• Incidence of dose limiting toxicities [177Lu-R11228]

  Number of participants with dose limiting toxicities

  Day 1 to week 36

Secondary Outcomes (24)

• Image quality

  Day 1

• Absorbed dose coefficients [68Ga-R11228]

  Day 1

• Standardized uptake value in tumor lesions [68Ga-R11228]

  Day 1

• Effective whole-body dose for 68Ga-R11228

  Day 1

• Pharmacokinetic parameters of 68Ga-R11228

  Day 1

Study Arms (2)

Part A: 68Ga-R11228 Dose Optimization Portion

EXPERIMENTAL

68Ga-R11228 injection at pre-defined dose levels.

Drug: 68Ga-R11228

Part B: 68Ga-R11228 Imaging and 177Lu-R11228 Dose Ranging Portion

EXPERIMENTAL

68Ga-R11228 injection at pre-defined dose. 177Lu-R11228 injection at pre-defined doses.

Drug: 68Ga-R11228; Drug: 177Lu-R11228

Interventions

68Ga-R11228 DRUG

68Ga-R11228 is a gallium-labeled small molecule radioligand that is designed to localize tumor lesions

Part A: 68Ga-R11228 Dose Optimization Portion; Part B: 68Ga-R11228 Imaging and 177Lu-R11228 Dose Ranging Portion

177Lu-R11228 DRUG

177Lu-R11228 is a lutetium-labeled small molecule radioligand designed to treat tumor lesions

Part B: 68Ga-R11228 Imaging and 177Lu-R11228 Dose Ranging Portion

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Part A
• Pathologically confirmed estrogen and/or progesterone receptor (ER/PR) positive and HER2 negative locoregionally recurrent or metastatic breast cancer
• At least one target or non-target lesion per RECIST v1.1 criteria.
• Male or non-pregnant, non-lactating female subjects age ≥18 years.
• Part B
• Pathologically confirmed estrogen and/or progesterone receptor (ER/PR) positive and HER2 negative locoregionally recurrent or metastatic breast cancer
• Refractory to endocrine therapy. Note: there is no limit on prior number of lines of endocrine therapy or prior treatments with CDK4/6, AKT, PI3K and/or mTOR inhibitors.
• Received or declined at least one line of chemotherapy or antibody drug conjugate in the locoregionally recurrent or metastatic setting
• Progressive disease or intolerance to last treatment.
• At least one target lesion per RECIST v1.1 criteria.
• Male or non-pregnant, non-lactating female subjects age ≥18 years.
• Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1.
• Life expectancy of at least six months.
• Adequate bone marrow reserve, hepatic function and renal function.

You may not qualify if:

• Part A
• Study participant has not recovered from clinically significant adverse event(s) resulting from most recent anticancer therapy/intervention.
• Known central nervous system (CNS) disease, except for those subjects with treated brain metastasis who are stable for at least 1 month, having no evidence of progression or hemorrhage after treatment and no ongoing requirement for corticosteroids, as ascertained by clinical examination and brain imaging (magnetic resonance imaging \[MRI\] or computed tomography \[CT\]) during the screening period.
• Radiotherapy for breast cancer ≤ 28 days prior
• Received a radionuclide within a period of less than 10 physical half-lives of the administered radionuclide prior to dosing with 68Ga-R11228.
• Any condition that precludes the proper performance of imaging procedures required in this study.
• Part B
• Study participant has not recovered from clinically significant adverse event(s) resulting from most recent anticancer therapy/intervention
• Treatment with anticancer therapy or with an investigational drug or device within 21 days or 5 half-lives of the agent (whichever is shorter)
• Known central nervous system (CNS) disease, except for those subjects with treated brain metastasis who are stable for at least 1 month, having no evidence of progression or hemorrhage after treatment and no ongoing requirement for corticosteroids, as ascertained by clinical examination and brain imaging (magnetic resonance imaging \[MRI\] or computed tomography \[CT\]) during the screening period.
• Radiotherapy for breast cancer ≤ 28 days
• Prior systemic radionuclide therapeutic treatment.
• Received a radionuclide within a period of less than 10 physical half-lives of the administered radionuclide prior to dosing with 68Ga-R11228.
• Any unresolved NCI-CTCAE Version 5.0 Grade 2 or higher toxicity (except alopecia and Grade 2 platinum-therapy related neuropathy) from previous breast cancer treatment and/or from medical/surgical procedures or interventions.
• Any condition that precludes the proper performance of imaging procedures required in this study.

Sponsors & Collaborators

• Radionetics Oncology: lead

Study Sites (7)

Indiana University Melvin and Bren Simon Cancer Center

Indianapolis, Indiana, 46202, United States

RECRUITING

United Theranostics

Glen Burnie, Maryland, 21061, United States

RECRUITING

United Theranostics Princeton

Princeton, New Jersey, 08540, United States

RECRUITING

University Hospital Seidman Cancer Center

Cleveland, Ohio, 44106, United States

RECRUITING

MD Anderson Cancer Center

Houston, Texas, 77030, United States

RECRUITING

University of Utah - Huntsman Cancer Institute

Salt Lake City, Utah, 84112, United States

RECRUITING

Melbourne Theranostic Innovation Centre (MTIC)

Melbourne, Australia

RECRUITING

Central Study Contacts

Kristrun Stardal

CONTACT

8582186617; kstardal@radionetics.com

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SEQUENTIAL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 6, 2025
• First Posted: August 13, 2025
• Study Start: October 1, 2025
• Primary Completion (Estimated): June 1, 2028
• Study Completion (Estimated): June 1, 2033
• Last Updated: April 13, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

AU (1); US (6)