NCT07191717

Imlunestrant and Abemaciclib for the Treatment of Estrogen Receptor Positive Breast Cancer in Patients With Minimal Residual Disease, MIRI Trial

Phase II Minimal Residual Disease Study of Selective Estrogen Receptor Degrader Imlunestrant With Cyclin-Dependent Kinase (CDK) 4/6 Inhibitor Abemaciclib in Patients With ER+ Breast Cancer (MIRI)

• Status: Not Yet Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 42 (estimated)
• Sponsor: Jonsson Comprehensive Cancer Center · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This phase II trial studies how well imlunestrant and abemaciclib work in treating patients with estrogen receptor positive (ER+) breast cancer who have tumor remaining in the blood following treatment (minimal residual disease). Estrogen can cause the growth of breast cancer cells. Imlunestrant lowers the amount of estrogen made by the body. This may help stop the growth of tumor cells that need estrogen to grow. Abemaciclib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Imlunestrant and abemaciclib may be effective in treating patients with ER+ breast cancer who have minimal residual disease.

Detailed description

PRIMARY OBJECTIVE: I. To determine the rate of circulating tumor deoxyribonucleic acid (ctDNA) clearance after 12 cycles of adjuvant imlunestrant and abemaciclib. SECONDARY OBJECTIVES: I. To investigate the safety and tolerability of 12 cycles of adjuvant imlunestrant and abemaciclib. II. To assess the rate of ctDNA re-emergence in the 12 cycles following treatment on imlunestrant and abemaciclib. III. To evaluate the 1-year distant recurrence-free survival (DRFS), defined as the time from enrollment to evidence of distant disease recurrence or death due to any cause. EXPLORATORY OBJECTIVE: I. To assess potential predictive biomarkers of response to imlunestrant and abemaciclib. OUTLINE: Patients receive abemaciclib orally (PO) twice daily (BID) and imlunestrant PO once daily (QD) on days 1-28 of each cycle. Cycles repeat every 28 days for up to 12 cycles in the absence of disease progression or unacceptable toxicity. Additionally, patients undergo blood sample collection throughout the study. Patients may also undergo radiological scans per the discretion of the treating physician throughout the study. After completion of study treatment, patients are followed up at 30 days and then every 4 months for 1 year.

Conditions

• Anatomic Stage I Breast Cancer AJCC v8
• Anatomic Stage II Breast Cancer AJCC v8
• Anatomic Stage III Breast Cancer AJCC v8
• Invasive Breast Carcinoma
• Localized Estrogen Receptor-Positive Breast Carcinoma
• Localized Human Epidermal Growth Factor Receptor (HER2)-Negative Breast Carcinoma

Interventions

Type	Name	Description
DRUG	Abemaciclib	Given PO
PROCEDURE	Biospecimen Collection	Undergo blood sample collection
DRUG	Imlunestrant	Given PO
OTHER	Questionnaire Administration	Ancillary studies
PROCEDURE	Radiologic Imaging Procedure	Undergo radiologic scans

Timeline

• Start date: 2026-04-30
• Primary completion: 2030-04-30
• Completion: 2031-04-30
• First posted: 2025-09-25
• Last updated: 2025-11-10

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study