Chronic hand eczema (CHE) can be extremely debilitating for patients and lead to disturbances of life, work, and sleep. In this seminar-in-depth, April Armstrong, MD, MPH, and Christopher Bunick, MD, PhD, take a deep dive into the epidemiology and pathogenesis of chronic hand eczema and review some of the latest treatments pending approval for CHE treatment. Chronic hand eczema is defined as eczema that persists for more than 3 months or recurs more than 2 times within a 12-month period. Symptoms fluctuate in severity over time and include pruritus, burning, and stinging.

Drs Armstrong and Bunick reviewed the 8 different etiologic subtypes of CHE, including irritant contact, allergic contact, atopic hand eczema, protein contact dermatitis, hyperkeratotic hand eczema, acute recurrent vesicular hand eczema, nummular eczema, and pulpitis. Of these, irritant contact dermatitis is the most common form of CHE, but in a large registry study of patients with CHE, 50% were classified as having more than one predominant subtype. Moving on to pathogenesis, Drs Armstrong and Bunick discussed that the JAK-STAT pathway is a driver for many of the CHE subtypes, including irritant contact dermatitis, atopic hand eczema, and allergic contact dermatitis. Historically, treatment of CHE has been limited to moderate and potent topical corticosteroids, despite surveys indicating that most patients would prefer a steroid-free topical therapy.

Pivoting to new treatments on the horizon, Drs Armstrong and Bunick introduced delgocitinib cream, a topical pan-JAK inhibitor. In pivotal Phase 3 trials of delgocitinib cream for CHE, 24.3% of delgocitinib-treated patients achieved IGA treatment success at Week 16 compared to just 8.4% of vehicle-treated patients. Long-term efficacy trials demonstrated maintenance of response out to 36 weeks. Delgocitinib led to rapid and sustained improvement in itch scores, with 47.2% of patients having a 4-point reduction in itch score at Week 16, compared to 21.6% of patients on vehicle. Improvement in itch compared to vehicle was seen as early as Week 2. Delgocitinib was well-tolerated in long-term efficacy and safety studies with no systemic pharmacologic effects expected with twice-daily use. In a match-adjusted indirect comparison, delgocitinib cream outperformed dupilumab over 16 weeks of CHE treatment in some measures.

To conclude, Drs Armstrong and Bunick discussed efficacy and safety data of ruxolitinib 1.5% cream, a topical JAK1/JAK2 inhibitor, for CHE. In a Phase 2 study, ruxolitinib 1.5% cream led to 53.2% of patients achieving IGA treatment success at Week 16, compared to just 10.9% of vehicle-treated patients. Improvement in itch was seen as early as Week 2. Ruxolitinib cream was well tolerated with no new safety signals observed.