One of the most significant recent advances in understanding atopic dermatitis is the recognition that itch is not just a consequence of skin inflammation, it is also driven by a distinct neurological signaling pathway that can be targeted directly. Nemolizumab is the first therapy designed to do exactly that.
What Is IL-31?
Interleukin-31 (IL-31) is a cytokine produced primarily by activated Th2 T cells, immune cells that are overactive in atopic dermatitis. IL-31 acts specifically on nerve fibers in the skin that express the IL-31 receptor, directly triggering the sensation of itch (pruritus).
This is a distinct mechanism from the inflammation-driven itch addressed by dupilumab. IL-31’s direct neural action explains why some patients have severe itch even when skin inflammation appears relatively controlled, the nerve-itch pathway remains active independently.
What Is Nemolizumab?
Nemolizumab is a monoclonal antibody that specifically blocks the IL-31 receptor A (IL-31RA). By preventing IL-31 from binding to nerve receptors, it directly interrupts the itch signaling pathway at its source.
What Clinical Trials Have Shown
Phase II and Phase III trials of nemolizumab in moderate-to-severe atopic dermatitis have demonstrated: – Significant and rapid reduction in itch intensity (as measured by the Peak Pruritus NRS scale), with many patients reporting meaningful improvement within the first week – Reduction in skin lesion severity (EASI score) as a downstream consequence of reduced scratching – Favorable safety profile with injection site reactions and atopic dermatitis exacerbations (during washout periods) as the most common adverse events
Nemolizumab has been approved for atopic dermatitis and prurigo nodularis in Japan and Europe and is being reviewed by the FDA.
What This Means for Patients
For patients who achieve adequate skin control on dupilumab or other biologics but continue to experience significant itch, nemolizumab addresses a parallel pathway that dupilumab does not directly target.
Contact NuLine about atopic dermatitis and itch-related clinical research.