On December 15, 2025, Biostar Pharma, Inc., the U.S. wholly-owned subsidiary of Beijing Huahao Zhongtian Biopharmaceutical Co., Ltd., announced the first patient dosing in its U.S. pivotal registrational clinical study (NCT06764940) evaluating Utidelone injection (UTD1), one of its core product's key overseas clinical pipelines, in combination with capecitabine for HER2-negative breast cancer brain metastases (BCBM).

The study adopts a two-stage design and plans to enroll approximately 120 subjects. The primary endpoint is central nervous system objective response rate (CNS-ORR). Nearly 20 leading research centers across the United States are participating, including MD Anderson Cancer Center, Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, City of Hope-Duarte, Robert H. Lurie Comprehensive Cancer Center at Northwestern University, University of Colorado Hospital, Augusta University, and University of California Los Angeles, among others.

Utidelone's unique physicochemical properties and its insensitivity to P-glycoprotein-mediated efflux confer upon it the ability to penetrate the blood-brain barrier (BBB) and prevent/treat solid tumor brain metastases, standing in stark contrast to taxanes, another class of microtubule stabilizers. A Phase II clinical study of Utidelone combined with bevacizumab and chemotherapy for HER2-negative BCBM, presented as an oral report at the 2025 ASCO Annual Meeting, enrolled 34 patients and showed a CNS-ORR of 67.6%, a CNS clinical benefit rate (CNS-CBR) of 88.2%, and a median CNS progression-free survival (CNS-PFS) of 15 months. Another Phase II study of Utidelone combined with bevacizumab for HER2-negative BCBM, published in JAMA Oncology in 2025, enrolled 47 patients and showed a CNS-ORR of 42.6%, a median CNS-PFS of 10.6 months, and a median overall survival of 15.1 months. In both studies, treatment-related adverse events (TRAEs) were mostly Grade 1-2, manageable, and reversible. Utidelone has also been granted Orphan Drug Designation by the U.S. FDA for the treatment of breast cancer brain metastases.

Approximately 20-50% of patients with advanced breast cancer will develop brain metastases. Due to the presence of the BBB, many breast cancer therapeutics struggle to achieve effective concentrations intracranially, resulting in generally poor prognosis for BCBM patients, particularly those with HER2-negative BCBM, who have a median progression-free survival of only 2-6 months. Currently, there is no effective pharmacological treatment for HER2-negative BCBM, and no drug has been approved globally for this indication, representing a significant and urgent unmet clinical need. Utidelone has the potential to change this, offering new treatment options and hope of survival for these patients.