Impact of Tofacitinib on Components of the ACR Response Criteria: Post Hoc Analysis of Phase III and Phase IIIb/IV Trials

Objective. To evaluate the effect of tofacitinib (TOF) on American College of Rheumatology (ACR) response criteria components in patients with rheumatoid arthritis (RA). Methods. This post hoc analysis pooled data from RA phase III randomized controlled trials (RCTs) assessing TOF 5 or 10 mg BID, adalimumab (ADA), or placebo, with conventional synthetic disease-modifying antirheumatic drugs, and a phase IIIb/IV RCT assessing TOF 5 mg BID monotherapy, TOF 5 mg BID with methotrexate (MTX), or ADA with MTX. Outcomes included proportions of patients achieving ACR20/50/70 responses and ≥ 20/50/70% improvement rates in ACR components at week 2 and months 1, 3, and 6; and mean percent improvement in ACR components and Clinical or Simplified Disease Activity Index (CDAI or SDAI) low disease activity or remission rates, at month 3, for ACR20/50/70 responders. Results. Across treatment groups, ≥ 20/50/70% improvement rates were numerically higher for most physician- vs patient-reported measures. In phase III RCTs, at earlier timepoints, ≥ 50/70% improvements in patient global assessment of disease activity, pain, and physician global assessment were similar. Among ACR20 responders receiving TOF, mean percent improvements for tender and swollen joint counts were > 70% at month 3. CDAI/SDAI remission was achieved at month 3 by 27.8-45.0% of ACR70 responders receiving TOF. Conclusion. Among ACR20 responders treated with TOF, physician-reported components particularly exceeded 20% response improvement. At month 3, disease state generally did not corroborate ACR70 response criteria. Divergences between physician- and patient-reported measures highlight the importance of identifying appropriate patient-reported outcome targets to manage RA symptoms in clinical practice.