Efficacy of add-on iguratimod in patients with rheumatoid arthritis who inadequately respond to either tocilizumab or tumor necrosis factor alpha inhibitors.

OBJECTIVES

This study aimed to evaluate the efficacy of add-on iguratimod (IGU) in patients with rheumatoid arthritis (RA patients) who inadequately respond to either tocilizumab (TCZ) or tumor necrosis factor alpha inhibitors (TNFi).

METHODS

Twenty-three RA patients treated with TCZ (the TCZ group) and 23 RA patients treated with TNFi (the TNFi group) were enrolled in this 24-week retrospective study from our multicenter registry. All inadequate responders to either TCZ or TNFi received add-on IGU. Baseline demographics and disease activity at 24 weeks after initiating add-on IGU were compared between the two groups.

RESULTS

Baseline clinical disease activity index (CDAI) values in the TCZ group and TNFi group were 14.1 and 11.8 ( = .24 between the two groups). At 24 weeks, CDAI values in the TCZ group and TNFi group were 5.1 and 7.5 ( = .002 and .002 compared to baseline, respectively) and ΔCDAI values were -9.0 and -4.3 ( = .007 between the two groups). Multiple linear regression analysis revealed that add-on IGU in the TCZ group was associated with greater improvement in CDAI relative to the TNFi group.

CONCLUSION

Add-on IGU was more effective in inadequate responders to TCZ than in inadequate responders to TNFi.