FDA Clears Biostar's Phase 2 Study of Utidelone for HER2- Breast Cancer Brain Metastasis

SAN FRANCISCO, July 5, 2024 -- Biostar Pharma, Inc., the U.S. subsidiary of Beijing Biostar Pharmaceuticals Co., Ltd., has announced that their lead product, Utidelone Injection (UTD1), has received approval from the US FDA to conduct a phase 2 study (BG01-2402) aimed at treating HER2-negative breast cancer brain metastasis (BCBM).

Breast cancer brain metastases affect about 20-50% of patients with metastatic breast cancer, depending on the molecular classification. The standard treatments for BCBM typically include surgical and radiation therapies, supplemented by drug treatments. However, the blood-brain barrier (BBB) and blood-tumor barrier (BTB) limit the efficacy of many drugs that work well for extracranial metastases, leading to poor prognoses for BCBM patients, particularly those with HER2-negative disease. Specifically, patients with hormone receptor-positive (HR+)/HER2-negative BCBM have a median progression-free survival (mPFS) of about 4-6 months, while those with triple-negative breast cancer (TNBC) brain metastasis have an mPFS of only 2.8 months.

Recent advancements in small-molecule tyrosine kinase inhibitors (TKIs) and antibody-drug conjugates (ADCs) have improved outcomes for HER2-positive BCBM patients. However, there remains a significant unmet need for effective treatments for HER2-negative BCBM, as no drugs have yet been approved for this condition globally.

Utidelone distinguishes itself from other treatments due to its ability to penetrate the BBB, thanks to its unique physicochemical properties and resistance to P-glycoprotein-mediated efflux. This capability has been demonstrated in preclinical studies and several clinical trials. A recent phase 2 study presented at the ASCO 2024 conference investigated utidelone in combination with bevacizumab for HER2-negative BCBM. The study showed promising results, with a central nervous system overall response rate (CNS-ORR) of 42.6%, a median progression-free survival of 7.7 months, and a 12-month overall survival rate of 74.4% among 47 patients. Results were even more favorable in the HR-/HER2- subgroup, showing a CNS-ORR of 55% and an mPFS of 8.4 months. The side effects were generally manageable, mostly being grade 1 or 2, indicating a promising balance between efficacy and safety for utidelone in treating HER2-negative BCBM.

In March 2024, Utidelone was granted "orphan drug designation" by the US FDA for the treatment of BCBM. Following this, Biostar filed an Investigational New Drug (IND) application for a phase 2 study focusing on HER2-negative BCBM. The FDA’s approval of this application is a significant step in Biostar's global development strategy.

The BG01-2402 study, titled "A Pivotal Phase II Clinical Trial of Utidelone Injection (UTD1) Plus Capecitabine (CAP) in HER2-negative Breast Cancer Patients with Brain Metastases," aims to assess both intracranial and systemic efficacy of the combination treatment. The trial will follow a Simon's 2-stage design and is planned to be conducted at 10-15 sites across the United States, with an enrollment target of 120 patients. The primary endpoint of the study is CNS-ORR, with secondary endpoints including progression-free survival (PFS), duration of response (DOR), and overall survival (OS).

Beijing Biostar Pharmaceuticals Co., Ltd. is an innovative biopharmaceutical company dedicated to developing first- and best-in-class anti-cancer drugs. Utilizing advanced technology platforms such as combinatorial biosynthesis and microbial fermentation, Biostar has built a well-balanced product pipeline, covering both advanced product life-cycle expansion and early-stage project development, supported by a state-of-the-art manufacturing facility and experienced R&D teams.