Background Biologic agents have improved the possibility of treatment of juvenile idiopathic arthritis (JIA). Infliximab has the longest history of using and despite of off-label status was administrated from 2004. Etanercept is available in Russia from 2009. Unfortunately some patients do not respond to them or have side effects. Drug survival is a general marker of the success of a treatment, as it depends on the drug efficacy and its side effects.
Objectives To evaluate drug survival (continuation rates on drug) of Biologic agents (BA) in JIA patients (pts), non-responders to conventional therapy DMARDs included.
Methods The study involved a prospective cohort of JIA patients taking different BA who attended our clinic from 2004 to 2014 with at least one year follow-up. Data on the disease course were used to estimate drug survival with Kaplan-Meier and calculate adverse event (AE) rates.
Results A number of 431 JIA pts, treated with one or more BA were analyzed. The average age of patients is 10,5 years (from 1,5 to 18 years). Median disease duration, from onset to the beginning of BA therapy was 7.1 years (interquartil range 1.3 -14.1). In total, 543 treatment series with etanercept (n=155), adalimumab (n=141), infliximab (n=117), abatacept (n=77), tocilizumab (n=53) were administered. There were 131 cases of BA withdrawals. Reasons for drug discontinuation were inefficacy 42% (etanercept 5%, infliximab 17%, adalimumab 5%, abatacept 13%, tocilizumab 1%), AE 33% (etanercept 5%, infliximab 20%, adalimumab 2%, abatacept 2%, tocilizumab 4%) or other 24% (etanercept 2%, infliximab 11%, adalimumab 10%, abatacept 1%, tocilizumab 2%). Etanercept treatment survival at 12 months was 98%, infliximab - 80%, adalimumab - 93%, abatacept – 89%, tocilizumab – 91%. Data is presented on diagram below.
Highest survival rates for TNF-inhibitors are associated with juvenile spondiloarthritis (JSA) group patients (Infliximab 64%, Adalimumab 89%, Etanercept 91%) and lowest with systemic arthritis (Infliximab 19%, Adalimumab 22%, Etanercept 78%).
Conclusions Infliximab therapy associated with the most discontinuation rate due to adverse events and inefficacy in compare of other BA. Among the subtypes of JIA, the risk of treatment discontinuation, TNF-inhibitors mostly, was highest in systemic arthritis. On the contrary, in JSA group patients the discontinuation rate was markedly low. In whole cohort of JIA patients etanercept and adalimumab have the optimal drug survival profile.
Disclosure of Interest None declared