Targeting the IL-31 receptor α (IL-31RA) in PN with subcutaneous injection of nemolizumab, 0.5 mg/kg every 4 weeks, improved clinical responses in adults with moderate to severe PN in a randomized, double-blind phase 2 clinical trial.20 Interleukin 31 is a neuroimmune cytokine that is associated with sensory neuronal outgrowth and stimulation, inflammation, and altered epidermal differentiation. The gene discussed is IL31; the disease is poikiloderma with neutropenia.