Outcomes of children with juvenile idiopathic arthritis receiving biological disease-modifying anti-rheumatic drugs: a retrospective single-centre experience from India.

BACKGROUND

We aimed to study the outcomes (remission, flare and adverse events) of biological disease-modifying anti-rheumatic drugs (bDMARD) in children with JIA from a low-middle-income country setting, and explore the factors associated with these outcomes.

METHODS

The Pediatric Rheumatology Clinic bDMARD register (2009 to August 2024) was screened to enrol children with JIA and at least 3 months follow-up whilst on bDMARDs. Participant characteristics and clinical responses were collected in a pre-designed proforma to evaluate the primary objective i.e., studying outcomes among children with JIA on bDMARDs. The secondary objective was to study factors associated with time-to-remission (TTR) and flare-after-stopping-bDMARDs.

FINDINGS

One-hundred-fifteen children (59.1% boys) with 168 patient-years of bDMARD use were enrolled for this single-centre study. Enthesitis-related arthritis was the commonest subtype of JIA (n = 44, 38.3%). The most commonly used bDMARD was adalimumab (n = 43, 37.3%). The median (IQR) delay to initiation of bDMARD from the perceived need was 2 (0-6) months, primarily due to financial impediments (n = 81, 70.4%). Fifteen (13%) children screened positive for tuberculosis infection. One hundred ten (95.6%) children achieved remission on bDMARD, after a median (IQR) of 7.5 (4-12) weeks. Macrophage activation syndrome at initiation was significantly associated (HR 3.6 (1.3-10.0), p = 0.03) with a longer time-to-remission. bDMARDs were stopped in n = 68/115 (59.1%) after a median (IQR) 15 (9.6-26.5) months, of whom n = 33/68 (48.5%) flared at 6 (3.5-12) months of follow-up. A longer time-to-remission (OR 1.12 (1.02-1.23), p = 0.01) was significantly associated with flare after stopping bDMARDs. Forty-two (36.5%) patients experienced adverse events. The most striking adverse events were serious infections requiring hospitalisation (n = 13, 11.3%) and tuberculosis (n = 4, 3.5%). All children who developed tuberculosis were on TNFi (Adalimumab).

INTERPRETATION

Though children on bDMARDs showed comparable remission rates, we noted a higher frequency of serious infections and tuberculosis, compared to the experience described from high-income countries. These observations highlight the need for further surveillance of outcomes of bDMARD use among children with JIA in an LMIC setting.

FUNDING

There has been no financial support for this work.