THU0326

DRUG SURVIVAL AND REASONS FOR DISCONTINUATION OF THE FIRST COURSE OF BIOLOGICAL THERAPY IN 301 JUVENILE IDIOPATHIC ARTHRITIS PATIENTS.

M. Romano ^1,*I. Pontikaki ²M. Gattinara ²I. Ardoino ³C. Donati ²P. Boracchi ³P. L. Meroni ^{4 5}V. Gerloni ⁶

¹Pediatric Rheumatology Un, ²Pediatric Rheumatology Unit, Ist. G. Pini, ³Statistica Medica, ⁴Rheumatology, Università degli Studi , ⁵Rheumatology, ⁶Pediatric Rheumatology Uniti, Ist. G. Pini, Milano, Italy

Objectives: To determine long-term effectiveness and safety of 1st biological treatment (BT) in a cohort of 301 Juvenile Idiopathic Arthritis (JIA) pts, not-responders to DMARDs, in terms of drug survival (continuation rate on therapy) and to identify the baseline predictors of treatment discontinuation, in a 10-year experience in a single centre

Methods: In our Pediatric Rheumatology Unit, each JIA pnt enrolled in a BT is prospectively assessed at the start of treatment and then every 3 mo for the evaluation of safety and efficacy according to ACR-Pedi30 criteria. All clinical charts of pts who started a BT between Nov'99 and Jul'10 have been retrospectively reviewed. Survival analysis methods were used to determine time drug discontinuation due to disease control (defined, according to Wallace criteria, as: Inactive Disease [ID], Clinical Remission on Medication [CRM], Clinical Remission [CR]), or failure (adverse event [AE], inefficacy or loss of efficacy according ACR-Pedi30)

Results: 301 JIA pts, non-responders or intolerant to DMARDs and treated with one or more cycles of BT, were identified. Median disease duration, from onset to the beginning of 1st BT, was 7.9 yrs (mean 9.7; range 0.2-41.4). Median disease duration before referral was 0.86 yrs (mean 2.7; range 0.2-34.1). The majority of our pts (57.1%) were enrolled in etanercept (172), 121 were enrolled in a monoclonal anti-TNF antibody (infiximab or adalimumab) and in total, as 1st course of BT, there were 293 treatments with anti-TNF agents, 5 were initially treated with abatacept and 3 with anakinra. Median duration of first BT was 23.9 mo (mean 31.6; range 0.5-126.3). A total of 157 pts discontinued BT: 25 due to disease control, 3 temporarily stopped for pregnancy and 129 because of failure (76 for AEs and 53 for lack or loss of efficacy). Among 129 pts who discontinued for failure, 115 switched to a 2nd BT and 14 were never retreated with BT. Among 25 pts who discontinued due to disease control, 10 pts restarted on it for relapse of disease activity. The cumulative incidence of pts who stopped the 1st BT due to AE was 18% at 24 mo, 28% at 48 mo and 29 % at 60 mo, while discontinuation for inefficacy was 13% at 24 mo, 18% at 48 mo and 22% at 60 mo. Drug withdrawal for disease control was 3.5% at 24 mo, 7% at 48 mo and 10% at 60 mo. Drug survival was 73% at 24 mo, 50% at 48 mo, and 44 % at 60 mo. Etanercept therapy was a predictor of continuation of the 1st course of BT (p<0.01). In multivariate analysis predictors of discontinuation of the 1st BT were systemic onset (vs other JIA subtypes) (p=0.001) and longer disease duration before referral (p<0.01)

Conclusions: Although only few pts discontinued BT due to a complete and persistent disease control, the majority of them remained on BT for a long time, suggesting that in our cohort of JIA pts affected by a severe long lasting refractory disease, BT was globally well tolerate and efficacious in controlling arthritis

Disclosure of Interest: None Declared