Background/Purpose: Self-reported disease activity (DA) indices such as RAPID3 (Routine Assessment of Patient [pt] Index Data 3) and RADAI (Rheumatoid Arthritis [RA] DA Index)1 offer a pt-focused approach to clinical management. RAPID3 is an index without formal joint counts, whereas RADAI includes a self-assessment of tenderness in 16 joint areas. This post hoc analysis of the REALISTIC (RA EvALuation In Subjects receiving TNF Inhibitor Certolizumab pegol [CZP]) study2 assessed the performance of RAPID3 and RADAI to measure impact of treatment with CZP in a broad population of RA pts closely resembling routine clinical practice.
Method: During the 12-week (wk), double-blind phase of REALISTIC (NCT00717236) 1063 pts with inadequate response to ≥1 DMARD were randomized 4:1 to CZP 400 mg at Wks 0, 2, and 4, followed by 200 mg at Wks 6, 8, and 10, or placebo (PBO), added to their current treatment. 75% pts were from North America. The RADAI (summarized as a joint tenderness score [JS] or the total score [TS], both ranging 0–10, with 10 indicating highest DA) was administered at 0, 2, 6, and 12 wks. Mean change from baseline (BL) in RADAI-TS was assessed using ANCOVA applying LOCF (CZP vs PBO). The % of pts achieving a minimum clinically important difference (MCID) for the RADAI-TS was evaluated (defined as a 1-point decrease). Correlations between RADAI-TS, RADAI-JS, RAPID3, and clinical DA measures (including DAS28[ESR] and total and swollen joint counts [TJC, SJC]) were examined using Pearson coefficients.
Result: Mean BL RAPID3 and RADAI-TS were similar between groups (CZP vs PBO: RAPID3 14.75 vs 15.50, RADAI-TS 5.56 vs 5.68). Statistically significant improvements in RAPID3 and RADAI-TS were reported with CZP vs PBO from as early as Wk 2 up to Wk 12 (Figure). Significantly more CZP pts had improvements ≥MCID in RADAI and achieved RAPID3 low DA or remission from Wk 2 onward. Correlations between RADAI (TS and JS) or RAPID3 and DAS28(ESR) were high, while correlations between RADAI-TS and RAPID3 were very high (Table). Pt-reported scoring of the joint for tenderness in the RADAI highly correlated with physician-reported TJC and moderately with SJC. Responsiveness of RADAI and RAPID3 was good, especially in pts with moderate or high number of affected joints at BL.
Conclusion: Rapid and significant improvements in RAPID3 and RADAI were observed within the first 3 months of CZP treatment in a broad population of RA pts. RADAI and RAPID3 may represent reliable pt-reported measures of DA in RA pts.
1. Uitz E, et al. Rheumatology 2000;39:542-549.
2. Weinblatt ME, et al. Ann Rheum Dis 2011;70(Suppl. 3);414.
Disclosure: M. E. Weinblatt, UCB Inc, 2, UCB Inc, 5 ; J. E. Pope, UCB Inc, 2, UCB Inc, 5 ; R. M. Fleischmann, UCB Inc, 5, UCB Inc, 2 ; C. O. Bingham, UCB Inc, 5, UCB Inc, 2 ; G. Coteur, UCB Inc, 3 ; M. Dougados, UCB Inc, 5, UCB Inc, 2 .