POS1327 DO JIA PATIENTS RESPONSE TO RE-TREATMENT AFTER A FLARE DURING TAPERING OF BDMARDS? A DESCRIPTIVE STUDY
Authors: A. García Fernández, A. Briones-Figueroa, L. Calvo Sanz, Á. Andreu-Suárez, A. Boteanu
Journal: Annals of the Rheumatic Diseases (2021)

Background: Tapering and withdrawal of biological DMARDs (bDMARDs) is often attempted in Juvenile Idiopathic Arthritis (JIA) patients but data about response to re-treatment after an unsuccessful tapering are scarce. Objectives: Our aim is to assess response to re-treatment after a disease flare during tapering or withdrawal of bDMARDs and to describe re-treatment strategies. Methods: A retrospective, descriptive study was conducted in a cohort of JIA patients followed up in a referral hospital and who had received bDMARDs between 2000 and 2019. All JIA patients with at least one flare during tapering or withdrawal were included. Response to re-treatment was defined as achieving Wallace criteria for remission for 6 months. Results: A total of 142 flares during tapering or withdrawal were identified and included. In 3/142 (2.1%) patients bDMARDS were not re-started after a flare, 1 due to patient refusal, 2 due to unplanned pregnancy. Main characteristics according to tapering strategies are reported in Table 1. Table 1. Main characteristics according to tapering strategies. Apso, Psoriatic Arthritis; ERA, Enthesitis related Arthritis; OligE, Oligoarticular Extended; OligP, oligoarticular persistent; Poly RF+, polyarticular rheumatoid factor positive; PolyRF-, polyarticular rheumatoid factor negative; sJIA, Systemic JIA; Und, Undifferenciated. Tapering Withdrawal Cases , n (%) 80 (57.5) 59 (42.4) Female , n (%) 57 (71.3) 36 (61) Age at diagnosis ,years, median (IQR) 5 (2-11) 4 (2-11) Age at start of tapering or withdrawal , years, median (IQR) 17 (11-25) 16 (8-29) Categories, n (%) OligP 19 (23.8) 12 (20.3) OligE 15 (18.8) 13 (22) sJIA 10 (12.5) 11 (18.6) ERA 12 (15) 8 (13.6) Apso 7 (8.8) 6 (10.2) Poly RF+ 9 (11.3) 4 (6.8) Poly RF- 7 (8.8) 3 (5.1) Und 1 (1.3) 2 (3.4) Uveitis , n (%) 24 (30) 16 (27.1) Laboratory values, n (% ) - RF 15 (18.8) 5 (8.5) - ANA 45 (56.3) 33 (55.9) cDMARDs at start of tapering , n (%) 40 (50) 20 (33.9) bDMARD target, n (%) - TNF inhibitors 63 (78.8) 45 (76.3) - IL6-blockers 14 (17.5) 5 (8.5) - IL1-blockers 2 (2.5) 7 (11.9) - Rituximab 1 (1.3) 2 (3.4) Line of bDMARD, n (%) - First 50 (62.5) 45 (76.3) - Second 18 (22.5) 10 (16.9) - Third 5 (6.3) 2 (3.4) - Forth 6 (7.5) 2 (3.4) - Fifth 1 (1.3) 0 (0) Time in bDMARD treatment , months median (IQR) 28.4 (13.3-52.5) 28.2 (13.9-44.6) Remission prior tapering or withdrawal, months median (IQR) 8 (6-12) 8 (6-12) Fifty-nine out of 80 (73.8%) tapering cases were on remission at 6 months (6m) and 42/80 (52.5%) at 12 months (12m). Regarding dosage schedule adjustments, interval widening was the most frequent in 70/80 (87.5%) followed by combined strategy in 7/80 (8.8%) and lower dosage in 3/80 (3.8%). Median remaining dosage administrated was 54.9% IQR(50-75). Median time to flare was 14.9 months IQR (5.6-24.7). Median time to re-start of bDMARDs was 0 months min-max(0-13). After withdrawal of bDMARDs 23/59 (39%)cases at 6m and 14/59 (23.7%) cases at 12m were on remission. Median time to flare was 4.7 months IQR (2.8-11.4). Median time to re-start of bDMARDs was 1 month min-max (1-6). Most frequent re-treatment strategies were re-start of standard dosage [tapering 42/80 (52.5%), withdrawal 34/59 (57.6%)], re-start of previous effective dosage [tapering 28/80 (35%), withdrawal 11/59 (18.6%)], change of bDMARD [tapering 6/80 (7.5%), withdrawal 6/59 (10.2), re-start of bDMARD and cDMARD [tapering 4/80 (5%), withdrawal 6/59 (10.2)] and re-start of cDMARD [tapering 0/80 (0), withdrawal 1/59 (1.7%)]. Overall response to re-treatment was 75/80 (93.8%) and 53/58 (91.4%) among tapering and withdrawal, respectively. In 12/139 (8.6%) patients bDMARD was changed, achieving remission in 11/12 (91.7%) cases. No factors were associated with response to re-treatment and there were no differences between re-treatment strategies and re-achieving remission (p=0.596). Conclusion: Response to re-treatment was high (92.7%), no risk factors were identified. Most frequent retreatment strategy was re-start of standard bDMARD dosage in 76/139 (54.7%) followed up by restart of previous effective bDMARD dosage in 39/139 (28.1%). Disclosure of Interests: None declared