Immune checkpoint is one of the most effective research targets for tumor immunotherapy. Immune checkpoint inhibitors, mainly programmed death receptor 1 and its ligand 1, have achieved good response rates in various tumor treatments, but some tumors still have low response rates. In recent years, bispecific antibodies have developed rapidly in the field of tumor research, because they can target multiple targets and play a combined role in tumor therapy, and can effectively inhibit tumor immune escape. This article reviews the research progress and clinical status of bispecific antibodies targeting immune checkpoints.

Interleukin-12 (IL-12) is a pro-inflammatory cytokine derived from antigen-presenting cells. IL-12 has a variety of effector mechanisms such as promoting T cells proliferation and cytotoxicity, inducing T cells and NK cells to secrete interferon-γ (IFN-γ), etc. IL-12 shows significant anti-tumor effect in preclinical stage and is quickly used in clinic, but its systemic administration has serious dose-limiting toxicity. At present, most of the research is about the topical use of IL-12 to reduce systemic toxicity, change tumor microenvironment and activate immune system. This article reviews the research progress and clinical trials of IL-12 in the treatment of solid tumors in recent years.