Eligibility Criteria for Active Ulcerative Pyoderma Gangrenosum in Clinical Trials: A Delphi Consensus on Behalf of the UPGRADE (Understanding Pyoderma Gangrenosum: Review and Assessment of Disease Effects) Group

At present, there are no standardized guidelines for determining patient eligibility for pyoderma gangrenosum (PG) clinical trials. Thus, we aim to determine which clinical features, histopathological features, or laboratory features should be included in active ulcerative PG clinical trial eligibility criteria for treatment-naïve patients and patients already treated with immunomodulating medications (treatment-exposed patients). This study employed 4 rounds of the Delphi technique. Electronic surveys were administered to 21 international board-certified dermatologists and plastic surgeon PG experts (June 2022–December 2022). Our results demonstrated that for a patient to be eligible for a PG trial, they must meet the following criteria: (i) presence of ulcer(s) with erythematous/violaceous undermining wound borders, (ii) presence of a painful or tender ulcer, (iii) history/presence of rapidly progressing disease, (iv) exclusion of infection and other causes of cutaneous ulceration, (v) biopsy for H&E staining, and (vi) a presence/history of pathergy. These criteria vary in importance for treatment-naïve versus treatment-exposed patients. Given the international cohort, we were unable to facilitate live discussions between rounds. This Delphi consensus study provides a set of specific, standardized eligibility criteria for PG clinical trials, thus addressing one of the main issues hampering progress toward Food and Drug Administration approval of medications for PG.