RC48 Plus Bevacizumab or Pyrotinib in HER2-Positive Metastatic Breast Cancer After T-DXd Failure: A Phase II Study

This multicenter, Phase II study (RADIANT-BC01) evaluates the efficacy and safety of Disitamab Vedotin (RC48) in combination with either bevacizumab or pyrotinib in adult patients with HER2-positive metastatic breast cancer whose disease has progressed on prior trastuzumab deruxtecan (T-Dxd) therapy. Eligible participants will be randomized 1:1 to receive RC48 plus bevacizumab (7.5 mg/kg IV every 2 weeks) or RC48 plus pyrotinib (320 mg orally once daily). Treatment continues until disease progression, unacceptable toxicity, withdrawal of consent, or initiation of new anticancer therapy. The primary endpoint is objective response rate (ORR); key secondary endpoints include progression-free survival (PFS), disease control rate (DCR), duration of response (DOR), overall survival (OS), and safety. This study aims to identify new post-T-Dxd treatment options and improve outcomes for patients with advanced HER2-positive breast cancer.

NCT Number	NCT07065435
Lead Sponsor	The First Affiliated Hospital with Nanjing Medical University Collaborators: RenJi Hospital, Anhui Provincial Hospital, The Affiliated Hospital of Xuzhou Medical University, The First Hospital of Jilin University, Shanghai Minhang Central Hospital, Zhejiang Cancer Hospital, Huai'an First People's Hospital
Conditions	HER2 + Breast Cancer
Enrollment	74 participants
Start Date	2024-01-01
Primary Completion	2025-12-01 (estimated)
Study Completion	2026-01-01 (estimated)
Updated on ClinicalTrials.gov	2025-07-15