Abstract 2712: Development of GB268, a tri-specific antibody targeting PD-1/CTLA-4/VEGF, with enhanced anti-tumor efficacy and reduced toxicity in pre-clinical studies

Abstract Background: Immunotherapy using immune checkpoint modulators such as anti-PD1/PD-L1 have been widely used in cancer therapy. Combination of checkpoint inhibition using anti-PD1 and anti-CTLA4 has improved therapeutic efficacy but is also accompanied by severe immune related adverse events (irAEs) which limited their clinical use. Bi-specific antibody targeting PD-1/CTLA-4 such as cadonilimab has shown improved clinical benefits with reduced irAEs in cervical cancer. Vascular endothelial growth factor (VEGF) is overexpressed in various solid tumors and anti-VEGF agents inhibit neovascularization and shrink tumor with time. Combined application of bevacizumab and PD-1/PD-L1 blockade displays durable and improved anti-tumor effects. We have recently developed a novel tri-specific antibody GB268, specifically targeting PD-1, CTLA-4 and VEGF with fine-tuned activity Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 2712.