Comparison of anti-IL-6 receptor and JAK inhibitors in patients with rheumatoid arthritis from the real-world practice FIRST study

Abstract Objectives A molecular-targeted drug that is suitable as the second choice for patients with rheumatoid arthritis (RA) who show an inadequate response to the first biological disease-modifying antirheumatic drug (bDMARD) is unknown. This study aimed to analyse the efficacy and safety of interleukin-6 receptor (IL-6Ri) and Janus kinase inhibitors (JAKis), often selected as molecular-targeted drugs for second or subsequent treatments. Methods The efficacy and safety of JAKis and IL-6Ri were compared using propensity score-based inverse probability of treatment weighting (PS-IPTW) using propensity scores after 26 weeks of therapy in patients with RA. Results The remission rate at week 26, determined by the clinical disease activity index (CDAI), and the incidence of infection were higher in the JAKis than in the IL-6Ri group. The CDAI trajectories were divided into four according to the growth mixture modeling. IL-6Ri demonstrated greater efficacy in RA patients with ineffective to single bDMARD therapy compared with those with multiple ineffective bDMARDs. In patients who failed to respond to one bDMARD, there was no significant difference in the CDAI remission rate at week 26 between the JAKis (29.1%) and IL-6Ri (21.8%) groups (P = 0.21). However, for patients who did not respond to at least two bDMARDs, the CDAI remission rate at week 26 was higher in the JAKis than in the IL-6Ri group. Conclusions IL-6Ri offers a superior balance of efficacy and safety compared with JAKis for RA patients unresponsive to one bDMARD. However, JAKis may suit patients who do not respond to multiple bDMARDs.