Background The role of biological anti-TNF agents (ATBA) in the treatment of rheumatological diseases (RD) has expanded, but dosing patterns have not been thoroughly explored.

Purpose To describe patterns of ATBA use among patients with RD.

Material and methods To describe patterns of ATBA use we retrospectively collected dispensing records of etanercept, adalimumab, golimumab and infliximab in first line (FL) or subsequent line (SL) settings, from 2011 to 2013, in a general teaching hospital. Variables included: average dose according to the standard dosing interval, dose escalation and discontinuation (gap in treatment >60 days or switch). Time to discontinuation was assessed with Kaplan-Meier curves and U Mann-Whitney tests for average comparisons (SPSS 15.0).

Results Over 3 years, average doses dispensed were: etanercept (N = 238) 40.2 ± 10.9 mg/week, adalimumab (N = 344) 44.9 ± 8.6 mg/2 weeks, golimumab (N = 38) 52.2 ± 1.6 mg/month, and infliximab (N = 139) 489.1 ± 188.6 mg/8 weeks. The overall percentages with dose escalation or discontinuation were greater in the SL for all ATBAs (42.2% SL vs. 28.6% FL, p = 0.039). The proportion with dose escalation was greater for infliximab patients (71.8% SL vs. 52.2% FL, p = 0.012), as well as for discontinuations (15.2% SL vs. 8.6%, p = 0.029). Time to discontinuation was significantly shorter for SL than FL for all ATBAs (median 10.6 vs. 14.9 months; p = 0.018). The hazard ratio for discontinuing SL vs. FL was 1.321 (p = 0.020).

Conclusion In RD ATBAs have higher rates of discontinuation, dose escalation, and shorter time to discontinuation in SL than in FL, therefore the correct selection of FL is a key question in this setting.

References and/or acknowledgements No conflict of interest.