A Review on the Effect of Tumor Necrosis Factor Inhibitors on Structural Progression in Early Axial Spondyloarthritis Using Magnetic Resonance Imaging

INTRODUCTION: Considering the progressive nature of axial spondyloarthritis (axSpA), it is important to determine whether tumor necrosis factor alpha (TNFα) inhibitors have an effect on early inflammatory and structural lesions detected using magnetic resonance imaging (MRI). METHODS: A search of MEDLINE/PubMed for full-text, English-language articles on randomized controlled trials (RCTs) of adalimumab, certolizumab, etanercept, golimumab, or infliximab published since January 2007 was conducted in February 2018 and again in December 2018. The collected articles reported on inflammatory or fatty lesion progression in the spine or sacroiliac joint (SIJ), determined using MRI, in a population that included at least 40% of patients with early axSpA, defined as non-radiographic axSpA. RESULTS: Of the 105 articles retrieved, 19 were included in this review, of which the majority were on etanercept (n = 11). A majority of selected articles included information on inflammatory lesions (SIJ 15/19; spine 12/19). All five TNFα inhibitors showed benefits on inflammation, assessed by MRI, in patients with early axSpA for up to 204 weeks of treatment. Structural progression in SIJ and the spine was assessed in 6/19 and 3/19 articles, respectively, with mixed evidence on benefits of TNF-inhibitor treatment. CONCLUSIONS: In conclusion, treatment with TNFα inhibitors reduces MRI-evident inflammatory lesions in the SIJ and spine of patients with early axSpA for up to 4 years. There is less evidence of benefits on structural lesions. Additional studies are required to determine whether TNFα-inhibitor therapy can limit or delay radiological progression in patients with early axSpA. FUNDING: Pfizer.