Patterns of biologic and targeted-synthetic disease-modifying antirheumatic drug use in rheumatoid arthritis in Australia.

objectiveThe aim of this study was to describe treatment patterns in RA, including the frequency and reasons for switching or stopping biologic and targeted synthetic DMARDs (b/tsDMARDs).

methodsThe reasons for switching or stopping b/tsDMARDs were extracted from the Australian Rheumatology Association Database (ARAD) from 2003 to 2018 for RA participants. Switching patterns for each b/tsDMARD and time on first-, second- and third-line b/tsDMARDs were evaluated using Sankey diagrams and survival methods.

resultsA total of 2839 participants were included in the analysis. The first-line b/tsDMARDs were etanercept (n = 1414), adalimumab (n = 1024), infliximab (n = 155), golimumab (n = 98), abatacept (n = 66), certolizumab (n = 38), tocilizumab (n = 21) and tofacitinib (n = 23). Of those starting first-, second- and third-line biologic therapy, 24.0%, 31.8% and 24.4% switched to another b/tsDMARD within 12 months, respectively. Inefficacy or adverse effects were the most common reasons for stopping therapy, irrespective of line of treatment. Compared with first-line etanercept, participants were more likely to stop adalimumab [Hazard ratio (HR) 1.16, 95% CI: 1.04, 1.29] and infliximab (HR 1.77, 95% CI: 1.46, 2.16). No differences were seen for other b/tsDMARDs. For second-line therapies compared with etanercept, the risk of stopping was lower for tocilizumab (HR 0.41, 95% CI: 0.25, 0.70), rituximab (HR 0.51, 95% CI: 0.30, 0.85) and tofacitinib (HR 0.29, 95% CI: 0.15, 0.57). Participants taking rituximab, tocilizumab and tofacitinib were also less likely to stop third-line therapy in comparison with participants taking etanercept.

conclusionsSwitching between b/tsDMARDs was common among ARAD participants with RA, most commonly due to inefficacy or adverse effects. Durability of exposure and reasons for switching varied between b/tsDMARDs.