Abstract
Objective: To examine whether to continue treatment with TNF inhibitor or switch to biological agent with a different target of action in outpatients with RA refractory to TNF inhibitor as the 1st biologic.
Subjects and methods: Since four biologics became available for our use in July 2008, we have examined 22 RA patients for at least 1 year of observation who were administered 2nd biologics: a TNF inhibitor in 11 subjects (T group) or an anti-IL-6 agent in 11 subjects (I group).
Results: All subjects received previous treatment of a single TNF inhibitor. The ratios of MTX combination as 2nd biologics were 36.3% and 18.2% in the T and I group (P＝0.635), and the ratios of PSL combination were 90.9% and 81.8% in the T and I group, respectively (P＝1.000). Mean DAS28-CRP values before the start and after 48 weeks (final observation) were 4.87±1. 16 and 4.62±1.27 in the T group, and 4.87±1.47 and 1.93±0.91 in the I group, respectively. The 48-week treatment completion rates were 36.4% (4/11) in the T group and 81.8% (9/11) in the I group. The numbers of subjects who discontinued the treatment due to inadequate response were 4 and 1 in the T and I groups, respectively, and the numbers of failures due to adverse events were 3 in the T group and 1 in the I groups.
Conclusion: Switching to an anti-IL-6 agent with a different mechanism of action may have a beneficial effect on patients with RA refractory to TNF inhibitor as the 1st biologic.
