Efficacy of iguratimod salazosulfapyridine as the first-line csDMARD for rheumatoid arthritis.

We retrospectively evaluated the retention rate and clinical responses following treatment for rheumatoid arthritis (RA) with iguratimod (IGU) salazosulfapyridine (SASP) as the first-line conventional synthetic disease-modifying antirheumatic drug (csDMARD). We analyzed 197 RA patients who were treated with IGU or SASP as the initial treatment in the 3-year study period. The retention rate, clinical response, the dosage and percent user of prednisolone (PSL), and safety profiles were evaluated. At month 36, the retention rates of the IGU and SASP groups were 52.4 32.1%. The rate of responders (good or moderate response) at month 36 was 85.8 65.2% in the IGU and SASP groups, respectively. At month 36 for the IGU and SASP groups, the percentages of PSL users were 16.7 46.7%, and the PSL dosage was 0.3 mg/d 2.0 mg/d, respectively. The cumulative rates of any adverse event (AE) at month 36 were 19.8 29.2% in the IGU and SASP groups, respectively. IGU is a useful first-line csDMARD treatment for RA patients, showing a high retention rate and good efficacy without an increased risk of serious AEs, including serious infections. Our findings also indicate a PSL dose-sparing effect of IGU treatment.