AB0826 PROBABILITY OF SURVIVAL OF USTEKINUMAB IN PSORIATIC ARTHRITIS: A REAL CLINICAL PRACTICE COHORT COMPOSED OF 64 PATIENTS

Background:Psoriatic arthritis (PsA) is an inflammatory disorder of unknown etiology. Several domains are affected as peripheral or axial joints, enthesitis, dactylitis, nails as well as skin. Diverse cytokines have been described in the pathology of PsA as TNFα, IL-17 and IL-23. Ustekinumab (UST) is a fully human IgG1κ monoclonal antibody to interleukin 12/23. Its efficacy and safety have been tested in several clinical trials and registries. Nevertheless data from real word evidence studies is needed to understand the effectiveness, safety and behavior of UST in a different population of patients from randomized controlled trialsObjectives:Analyze the persistence of UST 45 and 90 mg along 52 weeks of treatmentMethods:Drug survival, effectiveness and security of UST were studied in a population of 64 PsA patients treated in the period between August 2014 to October 2019. Drug survival was defined as the time from initiation to discontinuation (stop/switch) of bDMARDs. For the determination of drug survival, Kaplan-Meier survival curves and Cox-regression analyses were used. Effectiveness was described as a reduction in the use of corticosteroids and in the levels of CRP along the study. All adverse events were recorded during the studyResults:64 patients were included with a mean follow-up of 57,2 weeks. At baseline the mean age was 47,8 years (8,9). 54,7% of patients were women and 45,3% were male. 31,3% were obese. Mean disease duration was 7,9 (5,0) years. 45,3% presented peripheric arthritis; 32,8% axial involvement; 31,3% enthesitis; 80% psoriasis. Patients were 45% bDMARDs-naïve; had a previous bDMARDs in 20,3% and ≥ than two bDMARDs in 34,4%. 30% of the patients had co-therapy with methotrexate and 29,7% of patients received corticosteroid therapy. Mean CRP was 7,9 (12,7) mg/L. The global probability of survival for UST was 96%, 83,9% and 60% at week 12, 24 and 52 respectively. High UST dosage was associated with favorable drug survival (at 52W: UST 45 mg=40,1%; UST 90 mg=75,8%; UST 45 to 90 mg*=88,9%) (p=0,008). The bDMARDS-naïve population also correlated with favorable UST survival (at 52W: bDMARDS-naïve=66,1% vs bDMARDS-experienced=56,7%), however no statistical significance was found (p=0,196). No difference in survival was observed among patients with or without axial involvement (W52: axial=58,2% vs non-axial=61,6; p=0,869). UST produced a reduction in the use of corticosteroids (30% vs 16%) and CRP levels (8,7 vs 7,7). Differences were greater in patients treated more than 28 weeks (maximum efficiency described for UST) (corticosteroids: 26% vs 16%; CRP levels: 8,5 vs 4,4). 4,9% of the patients suffered an AE. Most of them were non-serious AE: infections (3,3%) or headache (1,6%). The main cause of treatment discontinuation was lack of efficacy (30%), followed by primary failure (9,4%) and just a 3% due to AEConclusion:The persistence of UST was dose-dependent and greater for the UST 90 mg dosage and for the population of bDMARD-naïve patientsDrug survival of UST in the population of patients with axial involvement seems similar to the population of patients without axial affection which provide evidence of the efficacy of the IL23 inhibition in the axial domain of PsAUST decreased the use of corticosteroids and CRP levels along treatmentThe security profile of UST was to the drug. Only few non-serious AE reported during this study*UST 45 to 90 mg, patients who change from UST 45 to UST 90 mg dosageReferences:[1]Ritchlin C. Efficacy and safety of the anti-IL-12/23 p40 monoclonal antibody, ustekinumab, in patients with active psoriatic arthritis despite conventional non-biological and biological anti-tumour necrosis factor therapy: 6-month and 1-year results of the phase 3. Ann Rheum Dis 2014;73:990–9[2]McInnes IB. Efficacy and safety of ustekinumab in patients with active psoriatic arthritis: 1 year results of the phase 3, multicentre, double-blind, placebo-controlled PSUMMIT 1 trial. Lancet 2013;382:780–9Disclosure of Interests:None declared