the Efficacy of Leucogen in Preventing the Risk of Ribociclib-Associated Neutropenia in Early Breast Cancer

This study is a multicenter, single-arm, open-label Phase II exploratory clinical trial designed to evaluate whether prophylactic use of leucogen can reduce the incidence of Grade 3 or higher neutropenia in early-stage HR+/HER2- breast cancer patients receiving ribociclib combined with endocrine therapy. The study plans to enroll 97 patients using a Simon two-stage design, with the primary endpoint being the incidence of severe neutropenia within 4 treatment cycles (4 months) after initiation. Secondary endpoints include the incidence of all-grade neutropenia, febrile neutropenia, ribociclib treatment intensity, and safety. The study will systematically assess the preventive efficacy and safety of leucogen to provide a basis for subsequent Phase III randomized controlled trials.

NCT Number	NCT07380646
Lead Sponsor	Second Affiliated Hospital, School of Medicine, Zhejiang University
Conditions	Leucogen, Ribociclib, Neutropenia (Low White Blood Cell Count), Breast Cancer
Enrollment	94 participants
Start Date	2026-01-07
Primary Completion	2028-01-01 (estimated)
Study Completion	2028-06-01 (estimated)
Updated on ClinicalTrials.gov	2026-04-30