No overall damage progression despite persistent inflammation in adalimumab-treated psoriatic arthritis patients: results from an investigator-initiated 48-week comparative magnetic resonance imaging, computed tomography and radiography trial

Abstract

In a comparative conventional MRI, dynamic contrast-enhanced (DCE)-MRI, CT and radiography study, the authors aimed to monitor whether inflammation is reduced or even eliminated and damage halted in PsA patients receiving anti-TNF therapy. A 48-week prospective open-label investigator-initiated trial of 41 biologic-naive patients treated with 40 mg adalimumab every other week. Hand CT, MRI (according to the PsA MRI scoring system method) and radiography (Sharp-van der Heijde method) were obtained at weeks 0, 6 (only MRI), 24 and 48. Clinical response was assessed by the PsA Response Criteria (PsARC). In the 23 PsARC responders at week 48, significant decreases from baseline in MRI synovitis (mean -2.0, P < 0.05), bone marrow oedema (BMO) (-1.3, P < 0.05), flexor tenosynovitis (-2.1, P < 0.05) and total inflammation (-6.0, P < 0.005) were observed. However, MRI signs of inflammation remained present (week 48 total inflammation score median = 9). Several DCE-MRI parameters also decreased (P < 0.05) and were correlated (ρ = 0.62) with conventional MRI total inflammation score. No statistically significant changes in bone erosion or proliferation scores were observed. With CT as the standard reference for detecting bone erosions/proliferations, sensitivity, specificity and accuracy were 100%/40%, 83%/93% and 84%/86%, respectively, for MRI, whereas corresponding values for radiography were 17%/26%, 98%/96%, and 93%/87%, respectively. Erosive progression as assessed by CT was found in 6 of 480 joints and baseline BMO was predictive (relative risk 10, 95% CI 2.1, 49). MRI signs of inflammation decrease, but do not disappear, during anti-TNF-α therapy. No overall changes in bone erosions or proliferations were observed. On joint-level baseline MRI, BMO was related to subsequent erosive progression detected by CT. ClinicalTrials.gov, http://clinicaltrials.gov/, NCT01465438.