Tofacitinib shows promise in curbing chronic itch
Chronic itch is a common condition that affects millions of people, but its causes are poorly understood. Now, researchers from Washington University School of Medicine, University of Cincinnati College of Medicine, and University of Cape Town have identified immune signaling pathways that mediate chronic itch.
Described in Cell on 7 September 2017, the study demonstrates that tofacitinib, a drug used in the treatment of rheumatoid arthritis, eases chronic itch with an unknown cause.
Chronic idiopathic pruritus, or itch of unknown origin, is a highly debilitating condition. Some patients with chronic idiopathic pruritus do not respond well to existing treatments. So new drugs are needed.
In this work, the researchers found that the patients taking tofacitinib exhibited a significant improvement of itch. Tofacitinib treatment curbed the need to scratch and allowed for better sleep.
The researchers identified the immune signaling molecules implicated in activating neurons in the skin that trigger chronic itch. They found that IL-4
activates sensory neurons in both mice and humans, and that chronic itch is mediated by neuronal IL-4Rα and JAK1
Tofacitinib belongs to the JAK inhibitor class. Although this study demonstrated the potential of tofacitinib in treating chronic itch, more research is needed to assess its safety and efficacy.
According to Dr. Brian Kim, corresponding author of the study and assistant professor at Washington University School of Medicine, future research will focus on whether tofacitinib or other similar drugs could be modified to relieve itch without disrupting the patients' immune system.
Chronic itch is an unpleasant sensory perception that can severely affect the quality of life. The sufferers usually have an intense desire to scratch. Chronic itch is a frequent symptom of diseases such as inflammatory disorders, but sometimes, the cause is unknown. Despite advances in the understanding of the pathogenesis of chronic itch, there are still many questions to be answered.