Evaluation of disease activity assessments in patients with rheumatoid arthritis and an inadequate response to anti-TNF therapy: analyses of abatacept clinical trial data.

OBJECTIVES: To assess the ability of efficacy measures that incorporate onset or sustainability to detect treatment effect or reflect patient satisfaction, using exploratory analyses of data from the ATTAIN (Abatacept Trial in Treatment of Anti-TNF INadequate Responders) trial. METHODS: 218 abatacept- and 99 placebo-treated patients were evaluated. Reporting methods included time to onset (first American College of Rheumatology [ACR] 50 response/Low Disease Activity State [LDAS; DAS28 < or =3.2]) and sustainability of ACR50/LDAS, both assessed according to discriminatory capacity (number of patients needed to study [NNS]) and patient satisfaction with treatment. RESULTS: Efficacy measures incorporating elements of sustainability or onset decreased discriminatory capacity, while sustainability, but not onset of action, was important in reflecting patient satisfaction. CONCLUSIONS: Optimal assessment methods depend on whether the outcome of interest is ability to detect treatment effects or to reflect patient satisfaction. Sustainability of response (and possibly, at a lower magnitude, fast onset of action) may be important when evaluating patient satisfaction with RA therapies in patients who have previously failed anti-TNF therapy