Advances in the study of CD47-based bispecific antibody in cancer immunotherapy

Tumour therapy has entered the era of immunotherapy. Monoclonal antibodies (mAb), immune checkpoint inhibitors, chimeric antigen receptor T-cell (CAR-T), cytokine-induced killer (CIK), tumour-infiltrating lymphocytes (TILs) and other cellular immunotherapies have become the focus of current research. The CD47/SIRPα target is becoming another popular tumour immunotherapy target following the PDCD1/CD247(PD1/PD-L1) checkpoint inhibitor. In recent years, a large number of CD47/SIRPα mAbs, fusion proteins, and CD47/SIRPα-based bispecific antibodies (BsAbs) are undergoing preclinical and clinical trials and have good curative effects in the treatment of haematological tumours and solid tumours. They bring new vitality and hope for the treatment of patients with advanced tumours. This review summarizes the research progress of CD47/SIRPα-based BsAbs with different targets for tumour treatment. There are 12 and 9 BsAbs in clinical trials and pre-clinical research, respectively. We report on the mechanism of 15 BsAb molecules with different target and analyse the efficacy and safety of preclinical and clinical trials, discuss the issues that may be faced in the development of CD47-based BsAbs, and dual-target molecules, and summarize their development prospects. This review provides a reference for the safety and effectiveness of BsAbs in clinical application and in the future development of antibodies.