POS0773 PRESCRIPTION PATTERNS AND EFFICACY OF THE SECOND BIOLOGIC AGENT IN JUVENILE IDIOPATHIC ARTHRITIS

Abstract

BackgroundBiologic agents (bDMARDs) have dramatically changed the disease course of juvenile idiopathic arthritis (JIA). TNF-α inhibitors (TNFi) are frequently used as first-line treatment, while there are no clear recommendations on the choice of the second bDMARD.ObjectivesWe aim to describe the prescription pattern of the second bDMARD in a cohort of non-systemic JIA patients.MethodsThis retrospective cohort study included non-systemic JIA patients treated with at least two bDMARDs followed in two Rheumatology Pediatric tertiary centers in Milan, Italy. Analyses were performed with R commander.ResultsThe study cohort included 39 patients; general features of the cohort are reported in Table 1. The median age at the first bDMARD was 5.9 [(interquartile range (IQR) 5.3] years. The prescription pattern of bDMARD is shown in Figure 1. Etanercept and adalimumab were the most frequently prescribed bDMARD (16 and 15 times, respectively). The causes of the first bDMARD discontinuation were the following: articular flare (43%), uveitis flare (33%), both articular and uveitis flare (6%), and adverse events (18%). Discontinuation of the first bDMARD due to articular flare was significantly more frequent in patients treated with adalimumab than with etanercept (73% vs. 25%; p=0.01). Conversely, the rate of bDMARD withdrawn due to active uveitis was higher in etanercept-treated patients than in adalimumab ones (38% vs. 20%; p=0.4).The discontinuation rate due to uveitis was significantly higher in the infliximab group than in the adalimumab group (80% vs. 20%; p=0.03).The median age at the second bDMARD was 9.4 (IQR 7.3) years. The majority of the cohort (80%) received a TNFi as the second bDMARD. Adalimumab was the most prescribed second bDMARD (55%) followed by infliximab (29%); the most frequent switch was from etanercept to adalimumab (13 times) (Figure 1). To note, the concomitant use of MTX decreased significantly between the two bDMARDs courses (85% vs. 64%; p = 0.04).The rate of clinical inactive disease (CID) at 3, 6, and 12 months did not differ significantly between the first and the second bDMARD. The general CID (defined as the ever achievement of CID) rate was lower during the first bDMARD course compared to the second (79% vs. 95%; p=0.04).A non-TNFi was prescribed as the second bDMARD in 8 patients (20%): 4 subjects received abatacept (2 for articular disease and 2 for adverse effects), and 4 subjects were treated with tocilizumab (all for articular disease).Uveitis activity represented the main reason for discontinuation in almost half of the patients who switched to a TNFi as the second bDMARD. No significant differences in efficacy were observed during the second course of bDMARDs between patients treated with TNFi or non-TNFi. Eighteen patients discontinued the second bDMARD: 16/31 (52%) from the TNFi group and 2/8 (25%) from the non-TNFi group. The reasons for discontinuation were articular flare (60%), uveitis flare (22%), both articular and uveitis flare (6%), and adverse events (12%).ConclusionMost of the patients in our cohort received a TNFi as the second bDMARD, with a significant proportion of patients being treated without MTX. No apparent differences were seen between the non-TNFi and TNFi for the achievement of clinical inactive disease. Larger studies are needed to explore the choice of the second bDMARD in JIA.Table 1.Demographic and clinical features of patientsClinical featuresSwitch to TNFi (n=31)Switch to non-TNFi (n=8)Overall population (n=39)p-valueGender, %F (n)87 (27)88 (7)87 (34)1Age at onset of symptoms, median (IQR)2 (3.7)3 (5.2)3 (4)0.651Uveitis, % (n)52 (16)50 (4)51 (20)1JIA subtype, % (n)Oligoarticular58 (18)38 (3)54 (21)0.432Polyarticular RF-19 (6)50 (4)25 (10)0.167Polyarticular RF +3 (1)13 (1)5 (2)0.372Enthesitis-related arthritis8 (3)0 (0)8 (3)1Psoriatic arthritis12 (4)0 (0)8 (3)1Duration of I bDMARDs, median (IQR)14 (35)29.5 (16.8)18 (31)0.347Follow-up time (months), median (IQR)112 (112)110.5 (82)112 (103.5)0.944Figure 1.Prescription pattern of biologic agents (bDMARDs) in the cohortREFERENCES:NIL.Acknowledgements:NIL.Disclosure of InterestsNone Declared.