Arthritis & Rheumatism, Volume 62,
November 2010 Abstract Supplement
Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Atlanta, Georgia November 6-11, 2010.
Comparison of ASAS Partial Remission and Low ASDAS as Indicators of Remission-Like States in Ankylosing Spondylitis.
van der Heijde4, Desiree, Sieper3, Joachim, Brown2, Steve, Lavie1, Frederic, Pangan2, Aileen
Definition of remission in patients with Ankylosing Spondylitis (AS) has previously been based on the ASAS partial remission (ASAS PR) criteria. More recently, the AS Disease Activity Score (ASDAS) was developed and cut-offs validated, including low ASDAS (<1.3) as indicator of a remission-like state.
To compare the performance of ASAS PR and low ASDAS in identifying patients in remission in the 5-year ATLAS (Adalimumab Trial Evaluating Long-Term Efficacy and Safety for AS) clinical trial and to determine potential causes of observed differences in response rates.
Patients were randomized to receive adalimumab (ADA) 40 mg every other week (wk) or placebo (PBO) during a 24-wk double-blind period, followed by an open-label extension of up to 236 wks (total of 5 years). Efficacy and safety were assessed throughout the study. We evaluated the proportion of patients achieving ASAS PR, low ASDAS, ASDAS clinically important improvement (CII, decrease of at least 1.10 from baseline) and ASDAS major improvement (MI, decrease of at least 2.00 from baseline) at weeks 12 and 24 using a non-responder imputation analysis; and at weeks 52, 104 and 260 using observed analysis. Because ASDAS is calculated using the same components as the ASAS PR except for BASFI, plus the addition of CRP and peripheral pain/swelling (BASDAI Question 3), we also determined if baseline BASFI and mSASSS scores contributed to the observed differences in ASAS PR and low ASDAS response rates.
ATLAS enrolled 315 patients (208 ADA, 107 PBO). Only patients in the ADA arm could have received 5 years of ADA therapy. At week 12 there were more subjects in the ADA arm compared with PBO who achieved ASAS PR (20.7% vs. 3.7%, P<0.001), low ASDAS (36.5% vs. 2.8%, P <0.001), CII (61.5% vs 17.8%, P <0.0001) and MI (39.9% vs. 3.7%, P <0.0001). At 1, 2, and 5 years of ADA exposure, the response rates (%) were higher for the 3 ASDAS-based response criteria compared with ASAS PR: (N, low ASDAS, CII, MI, ASAS PR) 1 year (N=282, 42%, 69%, 47%, 33%); 2 years (N=261, 53%, 77%, 53%, 38%); 5 years (N=124, 61%, 87%, 65%, 51%). Higher baseline BASFI and mSASSS were noted for subjects who achieved low ASDAS but not ASAS PR, compared with those who achieved both low ASDAS and ASAS PR (Table 1). Even higher baseline BASFI and mSASSS were noted for those who did not fulfill either criteria. BASFI was the most frequently observed ASAS component to have not met the required value of <20 in the sub-group "low ASDAS +/ASAS PR -."
Low ASDAS detects more subjects in a remission-like state and allows for better differentiation between active treatment (ADA) and placebo than ASAS PR. This is likely due to the inclusion of BASFI in ASAS PR criteria, which may not reflect response to effective therapies if irreversible damage and functional disability are present.
|Duration of Adalimumab Exposure||low ASDAS||ASAS PR||Mean (SD) Baseline BASFI||Mean (SD) Baseline mSASSS|
|Any ADA (N = 79)||+||+||42.85 (19.93)||12.75 (14.52)|
|Any ADA (N = 39)||+||-||51.84 (20.78)||20.55 (20.04)|
|Any ADA (N = 149)||-||-||61.53 (20.88)||25.67 (21.68)|
|Any ADA (N = 15)||-||+||48.52 (19.20)||15.64 (19.74)|
|Any ADA (N = 90)||+||+||44.03 (19.09)||12.25 (14.16)|
|Any ADA (N = 47)||+||-||55.79 (20.80)||24.76 (22.11)|
|Any ADA (N = 114)||-||-||61.06 (21.70)||25.77 (22.54)|
|Any ADA (N = 10)||-||+||62.49 (20.56)||17.50 (15.58)|
|Any ADA (N = 55)||+||+||42.23 (17.55)||12.77 (14.49)|
|Any ADA (N = 20)||+||-||54.27 (25.61)||25.19 (23.77)|
|Any ADA (N = 41)||-||-||62.44 (18.80)||27.60 (24.33)|
|Any ADA (N = 8)||-||+||62.35 (16.23)||24.29 (18.33)|
To cite this abstract, please use the following information:
van der Heijde, Desiree, Sieper, Joachim, Brown, Steve, Lavie, Frederic, Pangan, Aileen; Comparison of ASAS Partial Remission and Low ASDAS as Indicators of Remission-Like States in Ankylosing Spondylitis. [abstract]. Arthritis Rheum 2010;62 Suppl 10 :518