Trial of 225Ac-DOTATATE (RYZ101) in Subjects with ER+, HER2-negative Unresectable or Metastatic Breast Cancer Expressing SSTRs. (TRACY-1)

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Status and phase: Enrolling; Phase 2; Phase 1

Conditions: Metastatic Breast Cancer; HER2-negative Breast Cancer; ER+ Breast Cancer; Advanced Breast Cancer

Treatments: Drug: RYZ101

Study type: Interventional

Funder types: Industry

Identifiers

NCT06590857

RYZ101-201

Details and patient eligibility

About

Phase 1b/2 open-label trial of 225Ac-DOTATATE (RYZ101) in subjects with ER+, HER2-negative unresectable or metastatic breast cancer expressing SSTRs.

Enrollment: 124 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

Inclusion Criteria

Subjects must meet all the following criteria for enrollment in the study:

• Eastern Cooperative Oncology Group performance status ≤2.
• Histologically confirmed, ER+, HER2-negative, locally advanced and unresectable or metastatic breast cancer not amenable to treatment with curative intent.
• At least one RECIST v1.1-measurable tumor lesion that is SSTR-PET positive (defined as maximum standard uptake value (SUVmax) higher than liver mean standard uptake value (SUVmean) on SSTR-PET imaging) and at least 80% of RECIST v1.1measurable tumor lesions are SSTR-PET positive
• Sufficient renal function, as evidenced by eGFR ≥60 mL/min/1.73m2 calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation
• Adequate hematologic and hepatic function

Exclusion Criteria

Subjects who meet any of the following criteria will be excluded from the study:

• Prior radiopharmaceutical therapy, including radioembolization.
• Any toxicities from prior treatments that have not recovered to CTCAE Grade ≤1, except for alopecia.
• Significant cardiovascular disease
• Known active uncontrolled or symptomatic central nervous system (CNS) metastases, carcinomatous meningitis, spinal cord compression, or leptomeningeal disease.
• History of hypersensitivity or allergy to 225Ac, 68Ga, 64Cu, octreotate, or any of the excipients of DOTATATE imaging agents.
• Prior or concurrent malignancy whose natural history or treatment has the potential to interfere with the study safety or efficacy assessments.
• Pregnancy or lactation.

Trial design

Primary purpose: Treatment

Allocation: Non-Randomized

Interventional model: Sequential Assignment

Masking: None (Open label)

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124 participants in 2 patient groups

Dose Escalation

Experimental group

Description:

RYZ101 Dose Level -1 RYZ101 Dose Level 1 RYZ101 Dose Level 2 RYZ101 Dose Level 3

Treatment:

Drug: RYZ101

Expansion

Experimental group

Description:

RYZ101 RP2D Regimen

Treatment:

Drug: RYZ101