BIOSTAR PHARM-B(02563): Yutidelong treatment of brain metastases in breast cancer, the first patient in the United States treated with key clinical research.

BIOSTAR PHARM-B(02563) announced that its wholly owned US subsidiary, Biostar Pharma, Inc. (US-Biostar), has completed the first patient dosing of an important overseas clinical study: UTD1 in combination with capecitabine for the treatment of HER2-negative breast cancer brain metastasis (BCBM) in a key registration clinical study in the United States (NCT06764940). The study is designed in two stages, with a planned enrollment of approximately 120 subjects. The primary endpoint is the central nervous system objective response rate (CNS-ORR). Nearly 20 top research centers in the United States, including MD Anderson Cancer Center, John Hopkins Sidney Kimmel Comprehensive Cancer Center, City of Hope-Duarte, Robert H. Lurie Comprehensive Cancer Center of Northwestern University, University of Colorado Hospital, Augusta University, and University of California Los Angeles, are participating. The unique physicochemical properties and insensitivity to P-glycoprotein mediated efflux of UTD1 give it the ability to penetrate the blood-brain barrier (BBB) and treat solid tumor brain metastases, contrasting sharply with taxane drugs, which are also microtubule stabilizers. A Phase II clinical study presented at the 2025 ASCO conference reported that UTD1 in combination with trastuzumab and chemotherapy for HER2-negative BCBM enrolled 34 patients, with a CNS-ORR of 67.6%, CNS clinical benefit rate (CNS-CBR) of 88.2%, and a median CNS progression-free survival (CNS-PFS) of 15 months. Another study published in the 2025 JAMA Oncology journal on UTD1 in combination with trastuzumab for HER2-negative BCBM included 47 patients, with a CNS-ORR of 42.6%, a median CNS-PFS of 10.6 months, and a median overall survival of 15.1 months. Treatment-related adverse events (TRAEs) in both studies were mostly grade 1-2 and manageable and reversible. UTD1 has been granted orphan drug status for the treatment of breast cancer brain metastases by the US FDA. Approximately 20-50% of advanced breast cancer patients will experience brain metastases. Due to the presence of the BBB, many breast cancer treatments are unable to reach effective concentrations in the brain, leading to poor prognosis for BCBM patients with a median progression-free survival of only 2-6 months, particularly in HER2-negative cases. However, there is currently a lack of effective treatment options for HER2-negative BCBM globally, with no approved drugs for this condition, highlighting a significant and urgent unmet clinical need. UTD1 is poised to change this situation and provide new treatment options and hope for survival for these patients.