Intellectual property of tumour immunotherapeutic antibody fusion protein BY24.26: multi-targeted fusion protein blocking vascular endothelial cell growth and activating T cells and contained drug compositions (Patent Application No. 201910023522.6, International Patent Application No. PCT/CN2020/071213)

BY24.26 is a bifunctional immune fusion protein ( Y-trap structure ) composed of anti-VEGF antibody and CD80. It not only binds PD-L1, CTLA-4 and CD28 via CD80, but also binds VEGF via anti-VEGF antibody.  Therefore, it is a multifunctional immunofusion protein. It combines with PD-L1 and CTLA-4 to support the immune system. At the same time, its combination with CD28 can activate the CD28 / B7 signaling pathway, which provides a steady stream of power for lymphocytes that kill tumors. Through VEGF antibody, tumor angiogenesis was inhibited, blood vessel normalization was induced, immunosuppression was reduced, invasion of immune effector cells was enhanced, and tumor microenvironment was improved.

· Research results on the tumour immunotherapy antibody fusion protein BY24.26

BY24.26 In vivo activity

BY24.26 Lymphocytic infiltration of tumour tissue

In vivo mCD80-Fc immunotherapeutic effect is much better than mPD1; Expression vector construction completed; Stable cell screening; Expression amount reached above 1.0g/L; Purity: 99.4%; Affinity with VEGF is 1.53×10-11M; Binding with CTLA-4, CD28 and PD-L1 is low affinity binding; PBMC immune reconstitution model. HuH7 growth inhibition was higher in human HCC cells than in commercial O and K drugs, and synergistic effect with PD1; significant CD4+ and CD8+ lymphocyte infiltration and reduced number of blood vessels in hepatocellular carcinoma HUH7 model.