Treatment of Severe Hailey-Hailey Disease With Apremilast.

Importance: Hailey-Hailey disease (HHD) is a rare, autosomal-dominant acantholytic dermatosis characterized clinically by development of recurrent blisters and erosions in friction areas. Despite progression in our understanding of the molecular genetics of HHD, therapy remains suboptimal and there is no known cure. Objective: To determine whether the novel phosphodiesterase-4 inhibitor apremilast is effective in the treatment of HHD. Design, Setting, and Participants: Clinical case series of 4 patients with severe, treatment-resistant HHD at an outpatient clinic in the Department of Dermatology of Nice University Hospital, Nice, France. The patients were treated with apremilast; after the initial titration, the dose was 30 mg, twice daily. Main Outcomes and Measures: Objective clinical response was assessed by the treating dermatologist using the physician global assessment score; recorded adverse effects were monitored throughout the treatment at intervals of 2 to 3 months. Results: Three women and 1 man, with a mean age of 56 years, were treated and followed up for 6 to 10 months. Family history of the disease was noted in 3 (75%) of the cases. The lesions affected the axillary regions (75%), submammary regions (75%), inguinal regions (100%), and back and neck areas (50%). An improvement in the symptoms was reported by all of the patients after a treatment period of 1 month. After 6 months, the improvement of HHD lesions was reported as moderate to almost cleared among the patients. However, 2 patients developed some flares after 6 to 10 months of treatment and stopped apremilast therapy. One of the patients developed uncontrolled diffuse lesions and apremilast was reintroduced, resulting in partial control of her disease. Conclusions and Relevance: Apremilast appears to offer a low-risk therapeutic alternative or adjunct in resistant and severe forms of HHD. A prospective controlled trial with long-term follow-up is required to confirm these preliminary observations.