Palmoplantar pustulosis (PPP) is chronic inflammatory dermatosis characterised by sterile neutrophilic pustules on acral skin. Clinical, immunological and genetic data support a role of interleukin 1 (IL-1) in the pathogenesis of the disease. The aim of this study was to determine whether the IL-1 receptor antagonist anakinra delivers therapeutic benefit for PPP. We conducted a randomised (1:1), double-blind, two-staged, adaptive, UK multi-centre, placebo-controlled trial. Participants had disease duration greater than 6 months and severity warranting systemic therapy. Treatment was eight weeks of anakinra or placebo via daily self-administered subcutaneous injections. The primary outcome was the Palmoplantar Pustulosis Psoriasis Area and Severity Index (PPPASI) at 8 weeks. 374 patients were screened for inclusion in the trial and 64 patients were enrolled (31 anakinra, 33 placebo). The mean baseline PPPASI was 17.8 (SD=10.5) and PPP investigator’s global assessment was severe (50%) or moderate (50%). The baseline adjusted mean difference in PPPASI favoured anakinra but did not demonstrate superiority in intention-to-treat analysis, -1.65, 95% CI [-4.77 to 1.47], p=0.300. Secondary objective measures including fresh pustule count (2.94, 95% CI [-26.44 to 32.33] favouring anakinra), total pustule count (-30.08, 95% CI [-83.20 to 23.05] favouring placebo), and patient-reported outcomes, similarly did not show superiority of anakinra. No serious adverse events occurred. This study does not identify superiority of anakinra over placebo in the treatment of PPP but has created a highly effective clinical trial network for testing future interventions in this rare condition.

ESDR052 - Anakinra for palmoplantar pustulosis: results from a randomized, double-blind, multicentre, two staged, adaptive placebo controlled trial (APRICOT)

50th Annual Meeting of the European Society for Dermatological Research. VIRTUAL MEETING