Serious infection risk with systemic treatments for psoriasis: A cohort study from the British Association of Dermatologists Biologic Interventions Register (BADBIR)

BACKGROUND: Systemic treatments for psoriasis could increase the risk of serious infection due to their inhibitory effect on the immune system. OBJECTIVES: To estimate and compare the serious infection risk associated with systemic treatments for psoriasis. METHODS: Adult psoriasis patients who received at least one of the systemic treatments and had 6-month follow-up data in BADBIR database were included in the analysis. Patients were followed from the time of drug initiation to drug discontinuation, death or last available follow-up date. 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 weighting was used to balance baseline covariates. Hazard ratios and corresponding 95% confidence intervals were calculated using a piece-wise Cox proportional hazards model. A recurrent event analysis was also performed using Prentice-Williams-Peterson (PWP) model. Missing data were handled using multiple imputation. RESULTS: 46,770 treatment episodes from 18,976 patients were analyzed. Patients were predominantly male (n = 10,893; 57.4%) and had a mean age of 45.64 years (± 13.67) and mean BMI of 31.60 kg/m2 (± 7.28). The incidence rate of serious infections was 27.67 (95% CI, 26.72 to 28.65) and the rate of recurrent serious infection in those with prior infection was 78.70 (95% CI 75.17 to 82.36) events per 1000 person-years. The piecewise Cox proportional hazards model showed increased risk of serious infection with apremilast (HR 1.53; 95% CI 1.27 to 1.80) and secukinumab (HR 1.34; 95% CI 1.18 to 1.50) compared to adalimumab. However, these findings were not consistent across sensitivity analyses. The recurrent event analysis demonstrated lower risk with risankizumab compared with brodalumab (HR 0.74; 95% CI 0.55 to 0.99), etanercept (HR 0.75; 95% CI 0.60 to 0.94), and standard treatments (HR 0.80; 95% CI 0.65 to 0.98). Serious infection-associated deaths were rare (IR 1.81; 95% CI 1.57 to 2.07 per 1000 person-years). CONCLUSIONS: Despite isolated signals in the time-to-first event analysis, the more robust recurrent event analysis showed that risankizumab was associated with a lower risk of serious infections, while no significant differences were observed among the other systemic treatments for psoriasis.