Publications

This paper is based upon a long-term cohort study, namely the ANSWER cohort, an observational multi-centre registry of RA patients in the Kansai district of Japan. Analyses demonstrate a difference in observed drug retention between bDMARDs-naïve and bDMARDs-switched patients. 7 bDMARD treatments were compared in patients with no prior exposure to biologics, with abatacept showing the greatest retention rate. In patients that had switched between these same bDMARDs or to tofacitinib throughout treatment, tocilizumab was found to exhibit the greatest retention rate.Few studies have investigated the impacts of bDMARDs-naïve and bDMARDs-switched patient states on drug retention, despite reports of multiple other clinical confounders. This study aimed to clarify these variables, with the potential to provide evidence for the use of precision medicine to improve long term drug retention in patients. Gray’s test estimated cumulative incidence curves and discontinuation ratios of each treatment for both groups. Biologics-naïve patients demonstrated the greatest retention rate for abatacept of the 7 bDMARDs. 18.3% of these patients discontinued abatacept therapy over the course of the study (from 2001 to 2019). The biologics-switched group demonstrated the highest retention rate for tocilizumab of the 7 bDMARDs and tofacitinib. 18.9% of these patients discontinued tocilizumab therapy over the course of the study due to loss of efficacy.The Fine-Gray hazard competing risk regression model compared previously calculated discontinuation ratios, presented as HRs allowed further comparison between the agents using abatacept as a referent. Overall, significant differences in drug retention can be observed when considering outcomes in bDMARDs-naïve and bDMARDs-switched cases. Furthermore, higher rates of discontinuation are generally seen in the bDMARDs-switched groups, as shown by percentage values of therapy discontinuation.