Successful retreatment with spesolimab in refractory acrodermatitis continua of hallopeau after secondary loss of efficacy to adalimumab and secukinumab: a case report

Acrodermatitis continua of Hallopeau (ACH) is a rare, chronic, and relapsing localized pustular psoriasis that primarily affects the distal digits and nail apparatus. It is often refractory to conventional systemic therapies and biologics. We report a 64-year-old man with refractory ACH involving six fingers of both hands. He had a history of plaque psoriasis and psoriatic arthritis and had previously received acitretin, methotrexate, adalimumab, and secukinumab. Both adalimumab and secukinumab initially produced partial improvement but subsequently showed secondary loss of efficacy. At presentation, ACH was the only active cutaneous manifestation, with a baseline modified Nail Psoriasis Severity Index score of 53. The patient received spesolimab 900 mg intravenously on 12 February 2025 and again at week 4. Clinical remission was achieved at week 4, and the mNAPSI score decreased to 15. Remission was maintained until December 2025, when relapse occurred in three previously affected fingers. After retreatment with spesolimab on 15 March 2026, the lesions improved rapidly again. This case suggests that repeated IL-36 receptor blockade may be a potential strategy for relapsing refractory ACH.