Drug retention of biologic and targeted synthetic disease-modifying antirheumatic drugs in Korean patients with seropositive rheumatoid arthritis.

Background/aims: The aim of this study was to compare the short- and long-term retention rates of biologic and targeted synthetic disease-modifying anti-rheumatic drugs (b/tsDMARDs) in Korean patients with seropositive rheumatoid arthritis.

Methods: This study was conducted with 1,538 treatment courses of 1,063 patients, including adalimumab (n = 332), etanercept (n = 369), infliximab (n = 146), abatacept (n = 152), tocilizumab (n = 299), tofacitinib (n = 136), and baricitinib (n = 104), in patients with seropositive rheumatoid arthritis who started b/tsDMARD treatment between 2008 and 2020 at Seoul St. Mary's Hospital. Discontinuation 1 and 3 years after the first prescription of each drug was investigated. Kaplan- Meier estimates of time to discontinuation were calculated to compare the difference in drug retention rate for each drug. Patient-level predictors of drug discontinuation were evaluated using a Cox proportional hazards model.

Results: The overall 1-year drug retention rate was from 60.1% for adalimumab to 90.0% for tofacitinib in the b/tsDMARD-naïve group, and from 55.2% for infliximab to 84.8% for tofacitinib in the b/tsDMARD-experienced group. The 3-year drug retention rate was from 36.9% for infliximab to 86.5% for tofacitinib in the b/tsDMARD-naïve group, and from 31.0% for infliximab to 65.4% for tocilizumab in the b/tsDMARD-experienced group. Drug discontinuation appeared to be affected by specific types of b/tsDMARDs.

Conclusion: Tocilizumab and tofacitinib are less commonly discontinued compared to tumor necrosis factor-α inhibitors at 1 and 3 years. Specifically, tofacitinib in the b/tsDMARD-naïve group and tocilizumab in the b/tsDMARD-experienced group showed the highest 3-year retention rates.