Treatment Experiences with Intravenous Immunoglobulins, Ixekizumab, Dupilumab, and Anakinra in Netherton Syndrome: A Case Series

BACKGROUND: Netherton syndrome (NS) is a rare potential life-threatening disorder that causes severe defects to the skin barrier. No effective treatment options are available for patients with NS and current therapy is mostly supportive. The effects of intravenous immunoglobulins (IVIGs), ixekizumab, and dupilumab have scarcely been reported. Additionally, the role of anakinra in patients with NS has never been investigated. OBJECTIVES: The objective was to report our experiences of treatment with IVIG, ixekizumab, dupi­lumab, and anakinra in patients with NS. METHODS: A retrospective case series, including 5 patients with NS, was performed in a tertiary referral hospital between 2016 and 2021. Patients were treated with IVIG, ixekizumab, dupilumab, and/or anakinra. Long-term experiences with treatment regimens and adverse events requiring medical attention were reported. RESULTS: IVIG, ixekizumab, dupilumab, and anakinra were well tolerated with no severe adverse events. The 2 patients that received IVIG showed clinical response for 6 months and 2.5 years. Ixekizumab was effective in 1 of our patients for 3.5 years, while in another patient ixekizumab lost its effect after 1.5 years. Dupilumab treatment did not result in persistent improvement of NS-related skin symptoms in 1 patient. Anakinra showed physician-assessed clinical response during the first months of treatment in 4 patients with NS. During anakinra treatment, no changes in blood levels of IL-1β, IL-6, and TNF-α levels were measured at routine blood examinations. CONCLUSIONS: This case series suggests that the use of IVIG, ixekizumab, dupilumab, and anakinra in NS is safe and moderately effective on the short term. On the long term, a decline in effect was observed. Our experiences may help clinicians and researchers to provide adequate care and develop treatment for these severely affected patients. More international research, especially on the long term, is needed to determine if and which patients benefit most from the emerging therapies for NS.