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

Not Applicable
Not yet recruiting
Conditions
Locoregionally Recurrent Hormone-receptor Positive Breast Cancer
Metastatic Hormone Receptor Positive Breast Cancer
Interventions
Drug: 68Ga-R11228
Drug: 177Lu-R11228
Registration Number
NCT07121244
Lead Sponsor
Radionetics Oncology
Brief Summary

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

Detailed Description

Patients with metastatic or locoregionally recurrent ER+ and/or PR+ and HER2 negative breast cancer will be enrolled.

Part A is being conducted to test 68Ga-R11228, a new investigational product (IP) that has been designed to detect cancer lesions in the body and make them visible on a Positron Emission Tomography (PET) scan. Three dose levels of 68Ga-R11228 will be evaluated, with each patient receiving a single dose.

Part B is being conducted to test 68Ga-R11228 and additionally 177Lu-R11228, which has been designed to treat patients who have cancer lesions with positive uptake on PET scan using 68Ga-R11228. Patients who qualify for 177Lu-R11228 treatment will receive up to 6 doses over approximately 36 weeks. Multiple 177Lu-R11228 dose levels will be evaluated in Part B.

A 5-year Follow-Up Period begins once the last cycle of 177Lu-R11228 dosing is completed.

Recruitment & Eligibility

Status
NOT_YET_RECRUITING
Sex
All
Target Recruitment
62
Inclusion Criteria

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.
Exclusion Criteria

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.

Study & Design

Study Type
INTERVENTIONAL
Study Design
SEQUENTIAL
Arm && Interventions
GroupInterventionDescription
Part A: 68Ga-R11228 Dose Optimization Portion68Ga-R1122868Ga-R11228 injection at pre-defined dose levels.
Part B: 68Ga-R11228 Imaging and 177Lu-R11228 Dose Ranging Portion68Ga-R1122868Ga-R11228 injection at pre-defined dose. 177Lu-R11228 injection at pre-defined doses.
Part B: 68Ga-R11228 Imaging and 177Lu-R11228 Dose Ranging Portion177Lu-R1122868Ga-R11228 injection at pre-defined dose. 177Lu-R11228 injection at pre-defined doses.
Primary Outcome Measures
NameTimeMethod
Incidence of adverse events [68Ga-R11228]Day 1 to Day 7

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

Incidence of Serious Adverse Events [68Ga-R11228]Day 1 to Day 7

Number of participants with serious adverse events

Incidence of adverse events [177Lu-R11228]Day 1 to week 36

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

Incidence of Serious Adverse Events [177Lu-R11228]Day 1 to week 36

Number of participants with serious adverse events

Incidence of dose limiting toxicities [177Lu-R11228]Day 1 to week 36

Number of participants with dose limiting toxicities

Secondary Outcome Measures
NameTimeMethod
Pharmacokinetic parameters of 68Ga-R11228Day 1

Amount of 68Ga-R11228 excreted in urine

Standardized uptake value in tumor lesions [68Ga-R11228]Day 1

Standard uptake value (SUV) in tumor lesions

Image qualityDay 1

68Ga-R11228 positron emission tomography (PET) image quality as assessed by a 5-point Likert scale

Absorbed dose coefficients [68Ga-R11228]Day 1

Absorbed dose coefficients (milliGray \[mGy\]/megabecquerel \[MBq\]) in organs.

Effective whole-body dose for 68Ga-R11228Day 1

Effective whole-body dose (millisievert \[mSv\]/MBq) for 68Ga-R11228

Inter-reader agreementDay 1

Inter-reader agreement described by Fleiss' kappa coefficient

Number of study participants with at least one tumor lesion detectedDay 1

Number of study participants with at least one tumor lesion detected by imaging with 68Ga-R11228

Intra-reader reproducibilityDay 1

Intra-reader reproducibility described by Cohen's kappa coefficient

Proportion of tumor lesions detected by imaging with 68Ga-R11228 per study participantDay 1

Proportion of the number of tumor lesions positive with 68Ga-11228 imaging divided by the number of tumor lesions detected with standard of care images

Absorbed dose coefficients [177Lu-R11228]7 days

Absorbed dose coefficients (milliGray \[mGy\]/megabecquerel \[MBq\]) in organs and tumor lesions for 177Lu-R11228

Pharmacokinetic parameters of 177Lu-R112287 days

PK parameters, including apparent volume of distribution

Objective response rate36 weeks

Number of study participants with a complete or partial response divided by the number of study participants who had at least one 177Lu-11228 dose

Duration of response36 weeks

Time from achieving partial response or complete response to progression per RECIST v1.1 or death, whichever is sooner

Progression free survival36 weeks

Time from first 177Lu-R11228 dose until progression per RECIST v1.1 or death, whichever is sooner

Overall survival36 weeks

Time from first 177Lu-R11228 dose until death from any cause

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