A new avenue for treatment of chronic hand eczema
Authors: Marie L.A. Schuttelaar
Journal: British Journal of Dermatology (2022)

Linked Article: Worm et al. Br J Dermatol 2022; 187:42–51. Hand eczema (HE) is a prevalent disease with a lifetime prevalence of up to 15%.1 It strongly impacts patients’ quality of life, especially in patients with chronic HE (CHE). According to recently published guidelines for diagnosis, prevention and treatment of HE, topical corticosteroids are recommended as a short-term treatment for HE, as potent corticosteroids may cause skin atrophy and interfere with recovery in the long term.2, 4 The topical calcineurin inhibitor, tacrolimus, is also suggested for short-term treatment in patients with HE. In daily practice, it is used in patients refractory to topical corticosteroids, when fear of side-effects exists or in patients with CHE.2 For severe CHE, alitretinoin is the only registered systemic drug in some countries. Consequently, there is a significant unmet need for effective and safe topical treatments for long-term control of CHE. In this issue of the BJD, Worm and colleagues report the promising results of a 16-week double-blind, randomized phase IIb trial in which they explore the dose response, efficacy and safety of the topical pan-Janus kinase (JAK) inhibitor delgocitinib for CHE.5 Adults with mild-to-severe CHE were treated with delgocitinib cream 1, 3, 8 or 20 mg g−1, or cream vehicle twice daily for 16 weeks. Delgocitinib 8 mg g−1 and 20 mg g−1 showed a statistically significant treatment effect against vehicle; treatment success was achieved in 37% and 38% of patients, respectively. The treatment effect had not reached a plateau at week 16, suggesting that more prolonged treatment could show additional benefits. Delgocitinib was well tolerated without raising any safety concerns. It is strongly recommended to patch test all patients with CHE, which was also performed prior to the study from Worm et al.2, 5 However, patch testing results were not restrictive for inclusion. Consequently, patients entering the study could have had exposure to contact allergens that were highly relevant for the severity of their HE. As the proportion of patients with a main diagnosis of allergic contact dermatitis was rather small, this possibly had limited influence on the study results. JAK inhibitors target several cytokine pathways instead of one single pathway. Therefore, delgocitinib may benefit different aetiological and clinical subtypes of CHE. The current study included several subtypes of HE, but no data were presented on the effectiveness of delgocitinib on the different subtypes. This is an important issue that needs further assessment. In this study, patients with mild-to-severe HE were included. In general, mild eczema can be treated quite well with existing topical treatments. There is a large unmet need for effective treatment in patients with moderate-to-severe CHE. The effectiveness of delgocitinib in this subgroup should be evaluated separately in future studies. As clinicians, we need an effective and safe treatment option for prolonged treatment of patients with CHE in daily practice. Therefore, new data on the long-term effectiveness and safety should be awaited to draw firm conclusions on the value of this new drug for CHE treatment. As recommended in the Cochrane review on HE, head-to-head trials are needed – not comparing this treatment option with a vehicle, but comparing it with another established treatment. One example is the almost completed ALPHA trial.6, 7 Regardless of new treatment options, healthcare providers should keep in mind that ongoing attention for possible environmental triggers and patient education about skin protection and prevention are mandatory in patients with HE. the author would like to thank Pieter-Jan Coenraads and Laura Loman for reviewing and commenting on this text.