Biosion Initiates Phase 1 Trial of BSI-082 Anti-SIRPα Antibody for Advanced Solid Tumors
核心洞察
Biosion (搜索) has dosed the first patient in a Phase 1a/1b investigator-initiated trial of BSI-082, a next-generation anti-SIRPα (搜索) monoclonal antibody at the Mays Cancer Center (搜索).
BSI-082 is engineered to block the CD47 (搜索)-SIRPα (搜索) "don't eat me" signal while addressing safety concerns of earlier anti-CD47 therapies through reduced binding to red blood cells and platelets.
The trial will evaluate BSI-082 as monotherapy and in combination with trastuzumab deruxtecan in HER2-positive solid tumors (搜索), with preclinical data showing synergistic enhancement of ADC activity.
Biosion (搜索) has achieved a significant clinical milestone with the first patient dosing in a Phase 1a/1b investigator-initiated trial of BSI-082, a highly differentiated anti-SIRPα (搜索) monoclonal antibody for advanced solid tumors (搜索). The study is being conducted at the Mays Cancer Center (搜索), a National Cancer Institute-designated Cancer Center at The University of Texas at San Antonio's Health Science Center.
Novel Mechanism Targets Innate Immunity
BSI-082 is engineered to block the CD47 (搜索)-SIRPα (搜索) "don't eat me" signal, a critical checkpoint that tumor cells exploit to evade macrophage phagocytosis. The antibody was developed using Biosion (搜索)'s proprietary H³ Antibody Discovery Platform to address historical challenges faced by other candidates in this therapeutic class.
The drug demonstrates several key differentiators that position it as a next-generation therapy. BSI-082 provides broad population coverage through high-affinity binding to SIRPα (搜索) variants V1, V2, and V8, covering more than 90% of the human population. The engineered Fc domain minimizes binding to red blood cells and platelets, significantly reducing the risk of anemia (搜索) and thrombocytopenia (搜索) commonly associated with anti-CD47 (搜索) therapies. Additionally, BSI-082 does not bind to SIRPγ, preserving T-cell function and ensuring adaptive immune responses remain active.
"BSI-082's unique profile—specifically its ability to potently block the 'don't eat me' signal without compromising patient safety—positions it as an ideal combination partner for standard-of-care therapies, particularly antibody-drug conjugates," said Mingjiu Chen, Ph.D., Founder and CEO of Biosion (搜索).
Trial Design and Combination Strategy
The Phase 1a/1b study is an open-label, dose-escalation and dose-expansion trial designed to evaluate the safety, tolerability, pharmacokinetics, and preliminary antitumor activity of BSI-082 in patients with locally advanced or metastatic solid tumors (搜索).
Phase 1a will establish the Recommended Dose for Expansion of BSI-082 as a monotherapy. Phase 1b will evaluate BSI-082 in combination with trastuzumab deruxtecan (T-DXd) in patients with HER2-positive solid tumors (搜索). Preclinical data has demonstrated that SIRPα (搜索) blockade can synergistically enhance the antitumor activity of ADCs by promoting antibody-dependent cellular phagocytosis.
"Targeting the innate immune system via the SIRPα (搜索)-CD47 (搜索) axis offers a compelling therapeutic strategy for refractory tumors," said John Sarantopoulos, M.D., associate professor of medicine in the Division of Hematology and Oncology and principal investigator at the Mays Cancer Center (搜索). "We are excited to lead the clinical evaluation of BSI-082, whose design addresses key limitations of earlier generation agents."
Clinical Validation and Strategic Positioning
The initiation of this investigator-initiated trial represents validation of BSI-082's scientific rationale and therapeutic potential by a premier academic institution. This milestone follows Biosion (搜索)'s recent transformative partnership with Aclaris Therapeutics (搜索) for its immunology portfolio and highlights the medical community's strong interest in the company's oncology assets.
Biosion (搜索) operates through a flexible "Discover-Develop-Partner" model and has established over 10 global partnerships, with 9 programs currently in clinical development. The company's portfolio includes monoclonal antibodies, bispecific antibodies, and antibody-drug conjugates, developed using proprietary platforms including the H³ Antibody Discovery platform, the SynTracer® HT Endocytosis platform, and the Flexibody® Bispecific platform.