The effect of antimalarials on the safety and persistence of treatment with biologic agents or Janus kinase inhibitors in rheumatoid arthritis.

OBJECTIVES: To test the association of use of antimalarials with the overall safety of treatment in RA patients receiving one or multiple courses of biologic (b)DMARDs or a Janus kinase inhibitor (JAKi). METHODS: BiobadaBrasil is a multicentric registry-based cohort study of Brazilian patients with rheumatic diseases starting their first bDMARD or JAKi. The present analysis includes RA patients recruited from January 2009 to October 2019, followed up over one or multiple (up to six) courses of treatment (latest date, 19 November 2019). The primary outcome was the incidence of serious adverse events (SAEs). Total and system-specific adverse events (AEs) and treatment interruption served as secondary outcomes. Negative binomial regression with generalized estimating equations (to estimate multivariate incidence rate ratios, mIRR) and frailty Cox proportional hazards models were used for statistical analyses. RESULTS: The number of patients enrolled was 1316 (2335 treatment courses, 6711 patient-years [PY]; 1254.5 PY on antimalarials). The overall incidence of SAEs was 9.2/100 PY. Antimalarials were associated with reduced risk of SAEs (mIRR: 0.49; 95% CI: 0.36, 0.68; P < 0.001), total AEs (0.68; 95% CI: 0.56, 0.81; P < 0.001), serious infections (0.53; 95% CI: 0.34, 0.84; P = 0.007) and total hepatic AEs (0.21; 95% CI: 0.05, 0.85; P = 0.028). Antimalarials were also related to better survival of treatment course (P = 0.003). There was no significant increase in the risk of cardiovascular AEs. CONCLUSION: Among RA patients on treatment with bDMARDs or JAKi, concomitant use of antimalarials was associated with reduced the incidence of serious and total AEs and with longer treatment course survival.

Safety of the Methotrexate-leflunomide Combination in Rheumatoid Arthritis: Results of a Multicentric, Registry-based, Cohort Study (BiobadaBrasil).

OBJECTIVE: To evaluate the safety of the methotrexate (MTX)-leflunomide (LEF) combination in rheumatoid arthritis (RA), comparing it with other therapeutic schemes involving conventional synthetic (cs-) and biologic (b-) disease-modifying antirheumatic drugs (DMARDs) or Janus kinase inhibitors (JAKi). METHODS: Patients with RA starting a treatment course with a csDMARD (without previous use of bDMARD or JAKi) or their first bDMARD/JAKi were followed up in a registry-based, multicentric cohort study in Brazil (BiobadaBrasil). The primary outcome was the incidence of serious adverse events (SAEs); secondary outcomes included serious infections. Multivariate Cox proportional hazards models and propensity score matching analysis (PSMA) were used for statistical comparisons. RESULTS: In total, 1671 patients (5349 patient-years [PY]) were enrolled; 452 patients (1537 PY) received MTX + LEF. The overall incidence of SAEs was 5.6 per 100 PY. The hazard of SAEs for MTX + LEF was not higher than for MTX or LEF (adjusted HR [aHR] 1.00, 95% CI 0.76-1.31, P = 0.98). MTX + LEF presented a lower hazard of SAEs (aHR 0.56, 95% CI 0.36-0.88, P = 0.01) and infectious SAEs (aHR 0.48, 95% CI 0.25-0.94, P = 0.03) than bDMARDs/JAKi with MTX or LEF. MTX + LEF presented lower hazard of SAEs than MTX + sulfasalazine (SSZ; aHR 0.33, 95% CI 0.16-0.65, P = 0.002). Analysis using PSMA confirmed the results obtained with traditional multivariate Cox analysis. CONCLUSION: In our study, MTX + LEF presented a relatively good overall safety profile in comparison to MTX + SSZ and schemes involving advanced therapies in RA.