Abemaciclib for Molecular Residual Disease Detected by Circulating Tumor DNA in HR+/HER2- Early Breast Cancer

The goal of this clinical study is to determine whether monitoring ctDNA and treating patients who become ctDNA-positive with abemaciclib can help prevent the recurrence of hormone receptor-positive, HER2-negative breast cancer after curative surgery and standard therapy. The study will also assess the safety of abemaciclib and the medical problems that may occur during treatment. Participants will receive routine follow-up after surgery, undergo regular blood tests to measure ctDNA, and, if ctDNA becomes positive, receive abemaciclib for a defined treatment period with scheduled clinic visits for examinations and safety assessments. Researchers will evaluate recurrence-free survival, distant recurrence-free survival, adverse events, the time between ctDNA positivity and clinical recurrence, and the rate of ctDNA clearance at the end of abemaciclib therapy.

NCT Number	NCT07292207
Lead Sponsor	Nagoya City University Collaborators: Tohoku University, Japanese Foundation for Cancer Research, National Cancer Center, Japan, University of Tsukuba, Gifu University Graduate School of Medicine, Aichi Cancer Center
Conditions	ctDNA Monitoring, Breast Cancer
Enrollment	30 participants
Start Date	2026-01-10
Primary Completion	2028-11-30 (estimated)
Study Completion	2031-08-31 (estimated)
Updated on ClinicalTrials.gov	2025-12-18