Abstract
Background and Objectives: Palmoplantar pustulosis (PPPust) and palmoplantar psoriasis (PPso) are distinct palm/sole dermatoses that have historically shared the abbreviation "PPP". Though the two-since the advent of advanced biotechnology-are now deemed separate diagnoses, each still falls under the 'palmoplantar spectrum'. It is important to note that PPso and PPPust are each distinct from generalized pustular psoriasis (GPP), a condition that is outside the scope of our study. We quantified the relative efficacy of biologic and small-molecule monotherapies on the palmoplantar spectrum using Bayesian network meta-analyses (NMAs). Materials and Methods: On 6 November 2025, we searched PubMed, Scopus, ClinicalTrials.gov, and citations (i.e., citation mining) for randomized trials of monotherapy reporting PPP Area and Severity Index (PPPASI) outcomes at 12 or 16 weeks; we secondarily investigated fresh pustule-related outcomes at 4 weeks. We ran Bayesian NMAs with uniform priors; nodes were defined by dose and timepoint. Interventions' Surface Under the Cumulative Ranking Curve (SUCRA) values were computed; pairwise effects with 95% credible intervals were also estimated. Sensitivity analyses adjusted for diagnosis (pustulosis vs. psoriasis) via network meta-regression. Results: Twenty trials (n = 2030) with 23 active comparators provided data for 10 endpoints (fresh pustules at 4 weeks; PPPASI-50/75 and mean percentage and absolute PPPASI change at 12 and 16 weeks). Conclusions: The NMA indicates efficacy of ixekizumab and brodalumab (IL-17 inhibitors), guselkumab (IL-23 inhibitor), and spesolimab (IL-36 inhibitor) in managing palmoplantar pustulosis.