Interleukin 2-Based Cancer Immunotherapies: The Discovery of Next-Generation Antibody-Cytokine Bispecific Antibody Drug

Interleukin-2 (IL-2) is one of the first FDA-proved drugs in cancer immunotherapy. In the past 20 years, lots of new drug's development based on biased IL-2 agonist to expand the therapeutic window had been studied in preclinical and clinical trials. Unfortunately, most of them failed in different stages of clinical trials. Recently, the bispecific antibody which combined two drug-targets of IL-2 and another T cell agonist showed great efficacy in clinical trials. This viewpoint summarizes the history of novel drug design for recombinant IL-2 variants and concludes the promising drug design of IL-2-based bispecific antibodies according to the target mechanism-of-action (MOA) and preclinical/clinical data.