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

Abstract

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 (p = .24 between the two groups). At 24 weeks, CDAI values in the TCZ group and TNFi group were 5.1 and 7.5 (p = .002 and .002 compared to baseline, respectively) and ΔCDAI values were −9.0 and −4.3 (p = .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.

Keywords:

• Rheumatoid arthritis
• iguratimod
• inadequate response
• tocilizumab
• tumor necrosis factor alpha inhibitors

Conflict of interest

Y. Hirano received lecture fees from AbbVie Inc., Eisai Co., Mitsubishi Tanabe Pharma Co., Pfizer Inc., Chugai Pharmaceutical Co., and Bristol-Myers Squibb Co. N. Takahashi received lecture fees from AbbVie Inc., Eisai Co., UCB Japan Co., Mitsubishi Tanabe Pharma Co., Takeda Pharmaceutical Co., Pfizer Inc., Chugai Pharmaceutical Co., Janssen Pharmaceuticals, and Bristol-Myers Squibb Co. N. Ishiguro received grants and lecture fees from Daiichi Sankyo Co., Takeda Pharmaceutical Co., Hisamitsu Pharmaceutical Co., Otsuka Pharmaceutical Co., Taisho Toyama Pharmaceutical Co., Kaken Pharmaceutical Co., Eisai Co., Janssen Pharmaceuticals, Bristol-Myers Squibb Co., AbbVie Inc., Chugai Pharmaceutical Co., Mitsubishi Tanabe Pharma Co., Astellas Pharma Inc., and Pfizer Inc. T. Kojima received lecture fees from Mitsubishi Tanabe Pharma Co., Takeda Pharmaceutical Co., Eisai Co., AbbVie Inc., Bristol-Myers Squibb Co., Pfizer Inc., Janssen Pharmaceuticals, Astellas Pharma Inc., and Chugai Pharmaceutical Co. The other authors declare no conflicts of interest.