Comparative effectiveness of JAK inhibitors and biologic disease-modifying antirheumatic drugs in patients with rheumatoid arthritis

Abstract

Background/aims: We aimed to compare the effectiveness and safety of Janus kinase inhibitors (JAKi) vs. biologic disease- modifying antirheumatic drugs (bDMARD) in Korean patients with rheumatoid arthritis (RA) who had an inadequate response to conventional synthetic DMARDs.

Methods: A quasi-experimental, multi-center, prospective, non-randomized study was conducted to compare response rates between JAKi and bDMARDs in patients with RA naïve to targeted therapy. An interim analysis was performed to estimate the proportion of patients achieving low disease activity (LDA) based on disease activity score (DAS)-28- erythroid sedimentation rate (ESR) (DAS28-ESR) at 24 weeks after treatment initiation and to evaluate the development of adverse events (AEs).

Results: Among 506 patients enrolled from 17 institutions between April 2020 and August 2022, 346 (196 JAKi group and 150 bDMARD group) were included in the analysis. After 24 weeks of treatment, 49.0% of JAKi users and 48.7% of bDMARD users achieved LDA (p = 0.954). DAS28-ESR remission rates were also comparable between JAKi and bDMARD users (30.1% and 31.3%, respectively; p = 0.806). The frequency of AEs reported in the JAKi group was numerically higher than that in the bDMARDs group, but the frequencies of serious and severe AEs were comparable between the groups.

Conclusion: Our interim findings reveal JAKi have comparable effectiveness and safety to bDMARDs at 24 weeks after treatment initiation.

Keywords: Comparative effectiveness research; Janus kinase inhibitor; Rheumatoid arthritis; Safety; Tumor necrosis factor inhibitors.

Figure 1

Patient selection flow. RA, rheumatoid arthritis; DMARD, disease modifying anti-rheumatic drug.

Figure 2

Percentage of patients achieving low disease activity in the bDMARD and JAKi groups. (A) DAS28-ESR low disease activity and (B) CDAI low disease activity. Bar presents the mean with a 95% confidence interval of percentage (%) for patients achieving low disease activity. bDMARD, biologic disease-modifying antirheumatic drug; JAKi, Janus kinase inhibitors; DAS, disease activity score; ESR, erythrocyte sedimentation rate; CDAI, Clinical Disease Activity Index.

Figure 3

Percentage of patients achieving remission in the bDRARD and JAKi groups. (A) DAS28-ESR disease remission and (B) CDAI disease remission. Bar represents the mean with a 95% confidence interval of percentage (%) for patients achieving disease remission. bDMARD, biologic disease-modifying antirheumatic drug; JAKi, Janus kinase inhibitors; DAS, disease activity score; ESR, erythrocyte sedimentation rate; CDAI, Clinical Disease Activity Index.