Immuno-oncology agents (IO agents)

Immuno-oncology agents represent a broad therapeutic class of drugs designed to stimulate or restore the ability of the immune system to detect and destroy cancer cells (National Cancer Institute, 2023). Rather than being a single molecular target, this term encompasses various modalities including immune checkpoint inhibitors, chimeric antigen receptor (CAR) T-cell therapies, cancer vaccines, and cytokines (American Society of Clinical Oncology, 2022). These agents typically target specific proteins such as Programmed cell death protein 1 (PD-1), Programmed death-ligand 1 (PD-L1), or Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) to overcome the immunosuppressive environment created by tumors (Nature Reviews Drug Discovery, 2018). By modulating the immune response, these therapies aim to provide durable clinical benefits across a wide range of malignancies. However, their use is often associated with immune-related adverse events (irAEs) due to non-specific immune activation that can affect various organ systems (Journal of Clinical Oncology, 2021).

Other names

Cancer immunotherapyImmuno-oncology therapiesIO drugsBiological therapy for cancer

Immuno-oncology agents function by modulating the host immune system to recognize and eliminate malignant cells, primarily through the inhibition of immune checkpoints (e.g., PD-1/PD-L1, CTLA-4), activation of effector T-cells, or the administration of genetically modified immune cells (Nature Reviews Cancer, 2020).