SAN FRANCISCO, USA, July 5, 2024, Biostar Pharma, Inc., the U.S. subsidiary of Beijing Biostar Pharmaceuticals Co., Ltd. (Biostar), which is a synthetic biology-driven biopharma company focusing on the development and commercialization of innovative oncology drugs, announced today that their core pipeline product Utidelone Injection (UTD1) had been granted to conduct a phase 2 study (BG01-2402) for HER2- breast cancer brain metastasis (BCBM) by the US FDA.

Depending on the molecular classification of breast cancer, approximately 20~50% of metastatic breast cancer patients develop brain metastases.^[1] The current standard of care for BCBM is primarily local treatment with surgery and radiation therapy, supplemented by drug therapy. Due to blood-brain barrier (BBB) and blood-tumor barrier (BTB), many drugs that are effective for extracranial metastasis of breast cancer have very limited intracranial permeability, leading to poor prognosis for BCBM patients, especially with HER2- BCBM.^[2-3] The mPFS for HR+/HER2- BCBM is about 4-6 months,^[4-8] while the mFPS for TNBC brain metastasis is only 2.8 months.^[9]

In recent years, multiple small-molecule TKIs and ADC drugs have brought survival benefits to HER2+ BCBM patients. However, there is still a lack of drug treatment regimens with proven efficacy for HER2- BCBM, and no drug has been approved for HER2- BCBM worldwide, suggesting a significant unmet medical need.

Utidelone can penetrate BBB due to its unique physicochemical characteristics and insusceptibility to P-glycoprotein-mediated efflux, which has been confirmed by preclinical drug tissue distribution studies and several clinical trials. A phase 2 study of utidelone in combination with bevacizumab for the treatment of HER2- BCBM presented at the ASCO 2024 demonstrated efficacy outcomes of 42.6% of CNS-ORR, 7.7 months of mPFS, and 74.4% of 12-month OS rate with total 47 eligible patients being enrolled. The efficacy was even better in HR-/HER2- subgroup, showing 55% of CNS-ORR and 8.4 months of mPFS. The safety was manageable with majority of the AEs being Grade 1~2, suggesting a promising efficacy and manageable safety profile of utidelone for HER2- BCBM, and the potential of utidelone to become a new treatment option in the space.

Utidelone has been granted an “orphan drug designation” by the US FDA for the treatment of BCBM in Mar 2024. Biostar then filed an IND application for this phase 2 study for HER2- BCBM. The US FDA clearance of the application marks an important milestone of Biostar’s globalization development strategy.  

About BG01-2402 Study

BG01-2402 study refers to “A Pivotal Phase II Clinical Trial of Utidelone Injection (UTD1) Plus Capecitabine (CAP) in HER2-negative Breast Cancer Patients with Brain Metastases”. The purpose of the study is to evaluate the intracranial and systemic efficacy of Utidelone Injection in combination with capecitabine in HER2- BCBM patients. This study follows a Simon’s 2-stage design, and is planned to be conducted at 10-15 sites in the US with enrollment target of 120 patients. The primary endpoint is CNS-ORR; the secondary endpoints include PFS, DOR and OS, etc. 

Reference:

1. Lin, N. U., Gaspar, L. E. & Soffietti, R. Breast cancer in the central nervous system: multidisciplinary considerations and management. Am. Soc. Clin. Oncol. Educ. Book 37, 45–56 (2017).

2. Arvanitis, Costas D et al. “The blood-brain barrier and blood-tumour barrier in brain tumours and metastases.” Nature reviews. Cancer vol. 20, 1 (2020): 26-41. doi:10.1038/s41568-019-0205-x

3. Darlix A, Louvel G, et al. Impact of breast cancer molecular subtypes on the incidence, kinetics and prognosis of central nervous system metastases in a large multicentre real-life cohort. Br J Cancer. 2019 Dec; 121(12): 991-1000.

4. Leone, J.P. Emblem, K.E et al. Phase II trial of carboplatin and bevacizumab in patients with breast cancer brain metastases. Breast Cancer Res. 2020, 22, 131.

5. Chen X, Bai X, et al. The anti-tumor efficiency of low-dose apatinib-based chemotherapy in pretreated HER2-negative breast cancer with brain metastases. Ann Med. 2023 Dec; 55(1): 2218647.

6. Tolaney SM, Sahebjam S, et al. A Phase II Study of Abemaciclib in Patients with Brain Metastases Secondary to Hormone Receptor-Positive Breast Cancer. Clin Cancer Res. 2020 Oct 15; 26(20): 5310-5319.

7. Mosele F, Deluche E, Lusque A, et al. Trastuzumab deruxtecan in metastatic breast cancer with variable HER2 expression: the phase 2 DAISY trial. Nat Med. 2023; 29(8): 2110-2120.

8. Nadia Harbeck, et al. Trastuzumab deruxtecan vs treatment of physician’s choice in patients with HER2-low unresectable and/or metastatic breast cancer: Subgroup analyses from DESTINY-Breast04. 2022 SABCS. P1-11-01

9. Diéras V, Weaver R, et al. Abstract Pd13-07: Subgroup analysis of patients with brain metastases from the phase 3 ascent study of sacituzumab govitecan versus chemotherapy in metastatic triple-negative breast cancer. Cancer Res (2021)81 (4_Supplement): PD13–07-PD13-07

About Beijing Biostar Pharmaceuticals Co., Ltd.

Beijing Biostar Pharmaceuticals Co., Ltd. is an integrated biopharma company focusing on the development of first- and best-in-class innovative anti-cancer drugs with independent intellectual property through state-of-the-art technology platforms of combinatorial biosynthesis, microbial fermentation production and microbial drug formulation development. With an insight-driven strategy, experienced R&D teams, cGMP-compliant manufacturing facility and domestic commercialization capability, the company have built a balanced product pipeline, covering both lead product life-cycle expansion and early-stage projects development. Further information can be found on the company’s website http://www.biostar-pharm.com/en or by contacting our business development team at bd@biostar-pharma.com on partnering with us.

Source: Biostar Pharma