OP0075 Impact of Different Infliximab Dose Regimens on Treatment Response and Drug Survival in 462 Patients with PSA. Results from the Nationwide Registries Danbio and Icebio

Background International guidelines recommend that in psoriatic arthritis (PsA) infliximab should be dosed with 5 mg/kg bodyweight every 8th week. Data on the use of lower doses is however scarce. Objectives We aimed to describe dose regimens, dose escalation and clinical outcomes in tumor necrosis factor alpha-(TNFi)-naïve patients with PsA treated with infliximab in routine rheumatology care. Methods Observational cohort study based on the nationwide DANBIO and ICEBIO registries. Stratified by country, characteristics of patients treated with ≤3 mg infliximab/kg body weight, 3-5 mg/kg or ≥5 mg/kg/≈8 wks were described. Outcomes were evaluated by ACR20/50/70 and EULAR-good-response after 6 months, disease activity after 12 months, Kaplan-Meier plots and regression analyses. Results 462 patients (376 Danish, 86 Icelandic) received treatment with infliximab. In Danish patients, start dose was ≤3mg/kg in 110 patients (29%), 3-5 mg/kg in 157 (42%), ≥5mg/kg in 38 (10%) and unregistered in 71 (19%). In Icelandic patients, corresponding numbers were 64 (74%), 17 (27%), 0 (0%) and 5 (6%). Patients with higher body weight received lower doses per kg. Danish patients received higher doses than Icelandic at baseline (median (IQR) 3.1 (3.0-3.8) mg/kg vs. 2.3 (2.1-2.9) mg/kg, p