Transition of clinical remission rates with molecular targeted therapies in rheumatoid arthritis in Japan: insights from the FIRST registry.

Abstract

To elucidate the prevailing concerns by analysing the shifts in clinical profiles and therapeutic outcomes of patients with RA from 2003 to 2022, and offer guidelines to refine future treatment approaches. Utilizing our registry data, we conducted an analysis of the patient background and biennial variations in the clinical remission rate 1 year post-initiation of biological/targeted synthetic DMARDs (b/tsDMARDs) in patients with RA in Phase II. We investigated the determinants of remission. This study registered 2916 patients. Over time, the patient demographics evolved, characterized by an increase in the average age of patients, earlier initiation of b/tsDMARDs, and variability in the rate of concomitant use of MTX. The remission rate, as measured by the Clinical Disease Activity Index (CDAI), consistently rose from 2003 to 2013, then declined after reaching its peak in 2013. By 2021, it had returned to the same level observed in 2009. The findings of the multivariate analysis indicated that the factors contributing to CDAI remission after 1 year included the administration of MTX at a dosage of 10 mg/week or higher, the absence of concomitant glucocorticoid use, low disease activity, a low HAQ Disability Index score, and the utilization of Janus kinase (JAK) inhibitors. Specifically, since 2011, the use of MTX has declined alongside rising average serum creatinine levels. Additionally, the utilization of JAK inhibitors has rapidly decreased since 2021. Despite advancements in treatment and early intervention strategies, the clinical remission rate for RA has not shown consistent improvement. Factors contributing to this include reduced use of MTX.