Objective: With computed tomography (CT) and radiography to investigate if repair of bone erosions, defined as regression of erosion scores, occurs during adalimumab-treatment of rheumatoid arthritis (RA) patients.
Methods: Fifty-two RA patients, naïve to biologics, with at least two low-grade radiographic erosions in the wrist or metacarpophalangeal (MCP) joints in the same (index) hand, initiated adalimumab 40 mg sc. eow. Thirty-five patients completed the study (median age 61 years (range 19-86), disease duration 8 years (0-36)). CT of index wrist and MCP2-5 and radiographs of hands and forefeet were obtained at baseline, 6 and 12 months. Images were evaluated blinded to chronology and clinical data, and assessed according to Sharp/van der Heijde (radiographs) and OMERACT RA MRI scoring (CT) methods.
Results: All investigated parameters of disease activity had decreased at 6 and 12 months (P<0.001). No significant change in any imaging parameters of joint destruction was observed at 6 and 12 months. High intrareader agreements were reached (mean intraobserver intraclass coefficients: 0.96 (CT) and 0.97 (radiography)). The number of patients with change scores exceeding the smallest detectable change (SDC) was comparable on CT and radiography, as were proportions of patients progressing/regressing. Decreased erosion scores at 12 months were registered in 1.6% and 1.8% of sites assessed on CT and radiography respectively.
Conclusion: Repair of erosions in adalimumab-treated RA patients is rare, but erosive regression, exceeding the SDC, on CT and radiography occurred. The very limited overall erosive progression supports that joint destruction is minimal during adalimumab treatment of RA patients.