Biosion Inc, a China-based clinical-stage biotechnology company developing innovative antibody-based therapeutics, announced on Tuesday that the first patient has been dosed in a Phase 1a/1b Investigator-Initiated Trial (IIT) assessing BSI-082, a highly differentiated, fully human anti-SIRP alpha monoclonal antibody.

This study is sponsored by and being conducted at the Mays Cancer Center, a National Cancer Institute (NCI)-designated Cancer Center and part of The University of Texas at San Antonio's Health Science Center.

BSI-082 is engineered to block the CD47-SIRP alpha 'don't eat me' signal, a critical checkpoint that tumour cells use to evade macrophage phagocytosis. Unlike other candidates in the class, BSI-082 was designed using Biosion's proprietary H3 Antibody Discovery Platform to overcome historical development challenges.

The Phase 1a/1b study is an open-label, dose-escalation and dose-expansion trial designed to evaluate the safety, tolerability, pharmacokinetics, and preliminary anti-tumour activity of BSI-082 in patients with locally advanced or metastatic solid tumours.

Phase 1a will establish the recommended dose for expansion (RDE) of BSI-082 as a monotherapy, and Phase 1b will evaluate BSI-082 in combination with trastuzumab deruxtecan (T-DXd) in patients with HER2-positive solid tumours.