Ontorpacept

Ontorpacept (TTI-621) is a soluble fusion protein comprising the N-terminal (1-118) of human SIRPα fused to the Fc region of human IgG1. This N-terminal (1-118) segment serves as the binding domain for CD47, an inhibitor of macrophage-mediated phagocytosis. As a checkpoint inhibitor that blocks CD47, ontorpacept exhibits antitumor activity [1].