Validation of minimal disease activity criteria for psoriatic arthritis using interventional trial data

Abstract

Objective. New criteria for minimal disease activity (MDA) in psoriatic arthritis (PsA) have been developed. The aim is to provide further validation of these criteria using data obtained in interventional trials with infliximab, a drug with proven efficacy in PsA. Methods. The data were obtained from patients in phase II and III infliximab studies of PsA. In both studies, patients with active PsA were treated with infliximab (5 mg/kg) or placebo followed by a period of treatment with infliximab. Between-group comparisons in terms of those achieving MDA and the relationship of MDA to American College of Rheumatology outcomes, C-reactive protein levels, and radiologic progression were performed.

Radiographic Progression of Patients With Psoriatic Arthritis Who Achieve Minimal Disease Activity in Response to Golimumab Therapy: Results Through 5 Years of a Randomized, Placebo‐Controlled Study

“…The composite PsA MDA criteria have been preliminarily validated in both observational and interventional trial cohorts 5, 6. Also, it was previously found that MDA might be predicted after 3 months of anti‐tumor necrosis factor (TNF) therapy by factors such as baseline age, CRP level, and function (as assessed by the Bath Ankylosing Spondylitis Functional Index) in a smaller cohort (n = 146) of PsA patients 18.…”

“…For the purpose of these post‐hoc analyses, and as validated by Coates and Helliwell 5, MDA was defined as the presence of at least 5 of the following 7 PsA outcome measures: swollen joint count ≤1 of 66 evaluated; tender joint count ≤1 of 68 evaluated; Psoriasis Area and Severity Index (PASI) ≤1 (range 0–72)11; patient pain visual analog scale (VAS) score ≤15 (range 0–100); patient global assessment of disease activity VAS score of ≤20 (range 0–100); Health Assessment Questionnaire disability index (HAQ DI) score ≤0.5 (range 0–3)12, 13; and tender enthesis points ≤1.…”

“…As defined by the Outcome Measures in Rheumatology Clinical Trials (OMERACT) group, MDA is “that state of disease activity deemed a useful target of treatment by both the patient and physician, given current treatment possibilities and limitations,” and encompasses both remission and low disease activity 4. The PsA MDA criteria, a composite of 7 tools used to assess disease activity, have been preliminarily validated in both observational and interventional trial cohorts 5, 6.…”

Application and Modifications of Minimal Disease Activity Measures for Patients with Psoriatic Arthritis Treated with Adalimumab: Subanalyses of ADEPT

“…Although an improved prognosis was demonstrated in patients who achieved MDA, whether the improvements were a reflection of the disease course or due to treatment regimens could not be determined with the study design. The MDA criteria were subsequently validated using data from the randomized, controlled IMPACT and IMPACT2 trials in which patients received infliximab for the treatment of PsA 16 . In those trials there were statistically significant differences (infliximab vs placebo treatment) in the percentage of patients who achieved MDA at Week 16 (p < 0.0001) and Week 24 (p < 0.001).…”

Psoriatic arthritis: is it time to treat-to-target or target to treat?

“…Patients achieving MDA are more likely to have a better radiologic outcome, because the achievement of sustained MDA (defined as MDA for over 12 months at consecutive clinic visits) was found to reduce progression of radiographic joint damage over a 3-year period [14]. The MDA criteria were used in the TICOPA (Tight Control of PsA) study, the only randomized study to date addressing whether treating to target using a prespecified target can improve outcome in PsA [15].…”