Iguratimod, a synthetic disease modifying anti-rheumatic drug inhibiting the activation of NF-κB and production of RANKL: Its efficacy, radiographic changes, safety and predictors over two years’ treatment for Japanese rheumatoid arthritis patients

Abstract

Objective: To elucidate the clinical and radiographic outcomes for rheumatoid arthritis (RA) patients treated with a synthetic disease-modifying antirheumatic drug, iguratimod (IGU).

Methods: Clinical outcomes for 213 RA patients treated with 25 mg/day oral IGU or 50 mg/day after 4 weeks of 25 mg/day treatment for one day to 104 weeks were assessed.

Results: A total of 142 active RA patients (DAS28-ESR ≥3.2) treated for more than 12 weeks showed a significant reduction in both DAS and simplified disease activity index (SDAI) scores at week 4 (p < .001) to week 104. Good and moderate DAS responses were achieved in 54 (38%) and 66 (46%) patients, respectively. Total Genant-modified Sharp scores (GSS) of 31 patients at week 104 showed no progression (total GSS ≤0.84: the smallest detectable change) in 16 (52%) patients with a mean score reduction (95%CI) of −4.3 (−8.1∼−0.5) (p < .05). Predictors were an early response, moderate disease activity at baseline, and male gender. Eleven of the 213 patients had gastric and/or duodenal ulcer. A peculiar haemorrhage was seen in two patients treated concomitantly with IGU and warfarin potassium.

Conclusion: IGU treatment shows an early and sustained efficacy. Radiographically, no progression of GSS was evident in 16 (52%) patients at week 104. Gastric bleeding or gastric perforation warrants careful attention, especially in patients with concomitant use of both a non-steroidal anti-inflammatory drug and oral prednisolone.

Keywords:

• Clinical outcome
• iguratimod
• NF-κB
• RANKL
• synthetic DMARD

Acknowledgements

The authors acknowledge and thank Shizumi Taguchi, chief rheumatology nurse, and Shoko Kujima, managing director, of Ishikawa Orthopaedic and Rheumatism Clinic, for their kind cooperation.

Conflict of interest

None.

There is no claim or objection to publication of this article by Toyama Chemical Co., LTD., who developed and market iguratimod.