Brodalumab Improves Palmoplantar Pustulosis in Japanese Adults in Phase 3 Trial

BACKGROUND: The efficacy and safety of brodalumab in Japanese patients with palmoplantar pustulosis (PPP) were demonstrated during the 16-week double-blind phase of a randomized controlled trial. However, long-term data are unavailable. OBJECTIVES: To assess the efficacy and safety of brodalumab 210 mg administered subcutaneously (SC) repeatedly until Week 68 in PPP patients with moderate or severe pustules/vesicles in an open-label extension study. METHODS: In a multicentre, Phase 3, randomized, double-blind, placebo-controlled trial, Japanese adults having a diagnosis of PPP for ≥24 weeks, PPP Area Severity Index (PPPASI) of ≥12, PPPASI subscore of pustules/vesicles of ≥2 and inadequate response to therapy were included. Patients completing the double-blind phase with brodalumab 210 mg or placebo (1:1) SC once every 2 weeks (Q2W) for 16 weeks were invited to enter the open-label extension to receive brodalumab for the subsequent 52 weeks. RESULTS: By Week 68, 35 patients in the brodalumab group and 43 patients in the placebo-to-brodalumab group completed the study, with discontinuations (28 and 20 patients, respectively) primarily due to patient withdrawal. At Week 68, the mean ± SD improvement of the PPPASI total score from baseline was 23.83 ± 12.28 and 22.37 ± 13.09 in the brodalumab and placebo-to-brodalumab groups, respectively. Continued improvement or trend for improvement was seen in the secondary endpoints such as PPPASI 50/75/90 responses and Dermatology Life Quality Index. The incidence of adverse events was 849.3/100 person-years. Otitis externa had the highest incidence (44.0/100 person-years; Grade 1 or 2 only). Infection-related events were frequent but controllable. CONCLUSIONS: Brodalumab SC 210 mg Q2W administered for 68 weeks showed a long-term benefit to both dermatological and quality of life indices in these patients. It is expected to be used in appropriate patients, considering both safety risks and efficacy benefits.