Interleukin-6

Class

Anti-IL-6 monoclonal antibody

Interleukin-6 (IL-6) is a signaling protein, or cytokine, that cells release to coordinate inflammation and immune defense. It binds a receptor complex composed of an IL-6 receptor subunit and a signal-transducing partner called gp130, which activates intracellular signaling that switches on genes involved in inflammation, including production of acute-phase proteins such as C-reactive protein in the liver. While short-term IL-6 activity is a normal part of the response to infection or injury, sustained or excessive IL-6 signaling contributes to chronic inflammatory states. This has made IL-6 a target across a range of conditions, from inflammatory joint and bowel diseases to cancers where the cytokine supports tumor growth and cachexia, and more recently in cardiovascular and kidney disease, where chronic low-grade inflammation is thought to accelerate vascular damage. Anti-IL-6 monoclonal antibodies work by binding the cytokine directly, preventing it from engaging its receptor and blunting downstream inflammatory signaling. This approach differs from targeting the IL-6 receptor itself, but achieves a broadly similar functional outcome: interruption of the IL-6/gp130 signaling axis before it can propagate an inflammatory response.