FP08 Serious infection risk with systemic treatments for psoriasis: a cohort study from the UK and Ireland

Introduction and aims The objective of this study was to evaluate the serious infection (SI) risks associated with the systemic treatments when compared with one another in people with moderate-to-severe psoriasis. Methods Adults with psoriasis who received one of the systemic treatments and follow-up data in the British Association of Dermatologists Biologic and Immunomodulators Register registry, with the exception of infliximab and certolizumab because of a higher risk of confounding by indication, were followed up from the time of treatment initiation to last available follow-up date or death. Infections that occurred during or up to 90 days after treatment discontinuation resulting in hospitalization, administration of intravenous antimicrobials or death were considered serious. Inverse probability of treatment weights was used to balance baseline covariates, and risks were compared using Prentice–Williams–Peterson Cox regression model. Results A total of 44 556 treatment episodes from 18 686 patients were analysed, and there were 4926 SI events. Unadjusted incidence rate of first SI was 28.54 [95% confidence interval (CI) 27.54–29.58] and that of further SIs was 78.70 (95% CI 75.17–82.36) per 1000 person-years. After adjusting for potential confounders, there were no significant differences between treatments. We found uncertain evidence for an increased probability of SI with bimekizumab when compared with other comparators. None of the lower bound of the CI for the comparative effect estimates crossed 1, and the estimates against risankizumab [hazard ratio (HR) 1.62, 95% CI 1.00–2.63] and ixekizumab (HR 1.56, 95% CI 0.97–2.50) had the lower bound of the CI closest to 1. Conclusions SI risks were comparable between conventional treatments, tumour necrosis factor inhibitors, interleukin (IL)-17A inhibitors, ustekinumab and IL-23 inhibitors for psoriasis. We found an uncertain signal for an increased risk with bimekizumab, in particular when compared with ixekizumab and risankizumab, and more data are needed to confirm whether this effect is true and to quantify any difference in SI risk.