AntiIL31

Anti-IL-31 refers to therapies that inhibit the activity of interleukin-31, a cytokine implicated in itch and skin inflammation. IL-31 is produced by activated T helper 2 (Th2) cells and other cell types, and signals through a receptor complex composed of IL-31 receptor A (IL-31RA) and oncostatin M receptor (OSMR). Engagement of this receptor activates downstream pathways that contribute to pruritus and inflammatory responses in the skin.

Therapies described as anti-IL-31 include monoclonal antibodies that neutralize IL-31 or block IL-31RA, thereby preventing IL-31 from signaling. By reducing IL-31–driven signals, these agents aim to lessen itch and skin inflammation.

The most prominent example is nemolizumab, a humanized monoclonal antibody that targets IL-31RA. Nemolizumab has been evaluated in clinical trials for atopic dermatitis and other pruritic conditions, with phase II studies reporting reductions in pruritus and some improvements in skin disease measures. Development has continued in several countries, with ongoing trials exploring broader indications and long-term safety. Other anti-IL-31 antibodies or receptor antagonists have been investigated in preclinical or early clinical settings, reflecting ongoing interest in targeting the IL-31 pathway.

Safety and tolerability data from trials to date suggest that injection-site reactions and common infectious or allergic events may occur, as with many biologics, though a comprehensive safety profile requires results from larger and longer studies. Anti-IL-31 therapies represent a targeted approach to itch and inflammation with potential applications in atopic dermatitis, prurigo nodularis, and other pruritic conditions.