OBJECTIVES: To investigate changes in MRI inflammation and structural lesions in the sacroiliac joints (SIJ) during treatment with adalimumab (ADA) vs. placebo (PLA).
METHODS: In a 48-week double-blind placebo-controlled trial, 52 SpA patients were randomized to sc. ADA 40 mg (n=25) or PLA for 12 weeks, followed by ADA (n=27) eow. SIJ MRIs obtained at weeks 0, 12, 24 and 48 were assessed independently and blindly by use of the modified Berlin and Spondyloarthritis Research Consortium of Canada (SPARCC) SIJ MRI Inflammation and Structural Scores.
RESULTS: No baseline inflammation was observed in 44% of the ADA-group and 26-30% of the PLA-group. In patients having baseline inflammation, larger mean percentage reductions in MRI inflammation from week 0 to 12 were seen in ADA-group than PLA-group (Berlin/SPARCC: -52%/-58% vs -5%/-12%, both p<0.05). Furthermore, SPARCC erosion score decreased (mean -0.6) and SPARCC backfill score increased (+0.8) in ADA-group. From week 12 to 24, larger absolute reductions in Berlin/SPARCC inflammation scores and SPARCC erosion score, and larger increases in Berlin/SPARCC fat scores were seen in PLA-group than ADA-group. In univariate regression analyses (ANCOVA) and multivariate stepwise regression analyses treatment with adalimumab was independently associated with regression of SPARCC erosion score from week 0 to 12, but not with changes in the other types of MRI lesions.
CONCLUSION: Significant changes in Berlin and SPARCC MRI inflammation scores and in SPARCC erosion score occurred within 12 weeks after initiation of adalimumab. TNFα-inhibitor treatment was associated with resolution of erosion and development of backfill. This article is protected by copyright. All rights reserved.