The pan‐JAK inhibitor delgocitinib in a cream formulation demonstrates dose response in chronic hand eczema in a 16‐week randomized phase IIb trial*

Background Chronic hand eczema (CHE) is a burdensome disease, and new well-documented, safe and efficacious treatments are warranted. In a recent CHE phase IIa trial, the pan-Janus kinase (JAK) inhibitor delgocitinib in an ointment formulation was found to be efficacious and well tolerated. Objectives This trial assessed the dose response, efficacy and safety of delgocitinib cream in CHE. Methods In this double-blind, phase IIb dose-ranging trial, adults with CHE and a recent history of inadequate response or contraindication to topical corticosteroids were randomized to delgocitinib cream 1, 3, 8, 20 mg g–1 or vehicle treatment twice daily for 16 weeks. The primary endpoint was the Investigator’s Global Assessment for CHE (IGA-CHE) treatment success [0 (clear) or 1 (almost clear) with a ≥ two-point improvement from baseline to week 16]. Secondary endpoints were the time to IGA-CHE treatment success and changes in Hand Eczema Severity Index (HECSI); other endpoints were itch and pain numerical rating scale (NRS) scores, and Patient’s Global Assessment (PaGA) at week 16. Results Patients (n = 258) were randomized 1 : 1 : 1 : 1 : 1 to delgocitinib cream 1, 3, 8, 20 mg g–1 or vehicle. A significant dose–response relationship was established for IGA-CHE (P < 0.025). IGA-CHE treatment success at week 16 was achieved in 21.2% (1 mg g–1), 7.8% (3 mg g–1), 36.5% (8 mg g–1), 37.7% (20 mg g–1) and 8.0% (vehicle) of patients. Delgocitinib 8 and 20 mg g–1 showed a treatment effect against vehicle (P < 0.001). Similarly, there were improvements in HECSI, itch and pain NRS scores, and PaGA. Delgocitinib cream was well tolerated with the majority of adverse events being mild or moderate and considered unrelated to treatment. The most frequently reported adverse events were nasopharyngitis (17.3–29.4% in delgocitinib groups vs. 40% in vehicle group), eczema (5.8–11.3% in delgocitinib groups vs. 16.0% in vehicle group) and headache (3.8–11.5% in delgocitinib groups vs. 4.0% in vehicle group). Conclusions In this trial, delgocitinib cream showed a dose–response relationship in terms of efficacy and was well tolerated.