Single-center, retrospective analysis of efficacy and safety of tacrolimus as a second-line DMARD in combination therapy and the risk factors contributing to adverse events in 115 patients with rheumatoid arthritis.

To retrospectively evaluate the efficacy and safety of combination therapy with tacrolimus (TAC) and other disease-modifying antirheumatic drugs (DMARDs). One hundred fifteen rheumatoid arthritis (RA) patients treated with tacrolimus were enrolled in this retrospective analysis. We collected clinical information, including patient background, treatment efficacy (evaluated using the DAS score), and adverse events observed. Multiple logistic regression analysis was conducted to analyze factors contributing to clinical response and adverse effects. The disease activity score of 28 joints (DAS28) improved significantly at 24 weeks, and continuation rate at 1 year was 57.9%. There was no difference in continuation rate between different DMARD combinations, and not only methotrexate (MTX) but also bucillamine (BUC) and salazosulfapyridine (SSZ) were effective combination partners with TAC. No serious adverse events were observed, and no different inefficacy or safety was observed between non-elderly (<65 years old) and elderly (≥65 years old) RA patients. By conducting multiple logistic regression analysis, combination therapy with MTX and TAC, the number of baseline DMARDs (specifically, ≥3), and old age were identified as risk factors for adverse events. Our findings indicate that TAC is a valuable DMARD for second-line combination therapy in RA.