A study on the efficacy and Safety Evaluation of a novel PD-1/CTLA-4 bispecific antibody

Abstract

Tumors constitute a significant health concern for humans, and PD-1 and CTLA-4 monoclonal antibodies have been proven effective in cancer treatment. Some researchers have identified that the combination of PD-1 and CTLA-4 dual blockade demonstrates superior therapeutic efficacy. However, the development of PD-1/CTLA-4 bispecific antibodies faces challenges in terms of both safety and efficacy. The present study discloses a novel PD-1/CTLA-4 bispecific antibody, designated as SH010. Experimental validation through surface plasmon resonance (SPR) confirmed that SH010 exhibits favorable binding activity with both PD-1 and CTLA-4. Flow cytometry analysis demonstrated stable binding of SH010 antibody to CHOK1 cells overexpressing human or cynomolgus monkey PD-1 protein and to 293F cells overexpressing human or cynomolgus monkey CTLA-4 protein. Moreover, it exhibited excellent blocking capabilities in protein binding between human PD-1 and PD-L1, as well as human CTLA-4 and CD80/CD86. Simultaneously, in vitro experiments indicate that SH010 exerts a significant activating effect on hPBMCs. In murine transplant models of human prostate cancer (22RV1) and small cell lung cancer (NCI-H69), administration of varying concentrations of the bispecific antibody significantly inhibits tumor growth. MSD analysis revealed that stimulation of hPBMCs from three different donors with SH010 did not induce the production of cytokine release syndrome. Furthermore, Single or repeated intravenous administrations of SH010 in cynomolgus monkeys show favorable systemic exposure without noticeable drug accumulation or apparent toxicity. In conclusion, SH010 represents a novel cancer therapeutic drug poised to enter clinical trials and obtain market approval.