Background For ankylosing spondylitis (AS) and non-radiographic axial spondyloarthritis (nr-axSpA) patients, tumor necrosis factor (TNF) inhibitors are recommended when disease activity persists despite non-steroidal anti-inflammatory drugs.
Objectives To evaluate the efficacy and safety of TNF inhibitors in patients with AS and nr-axSpA.
Methods Searching PubMed, Embase, Cochrane Library, CNKI and WanFang databases, we included all double-blind randomized controlled trials (RCTs) that compared a TNF inhibitor with placebo in AS/nr-axSpA patients. The efficacy endpoints included the proportions of patients reaching Assessment in Ankylosing Spondylitis 20% response (ASAS20), ASAS5/6, partial remission, and Bath Ankylosing Spondylitis Disease Activity Index 50% improvement (BASDAI50). We used adverse events (AEs), withdrawals due to AEs and severe AEs to evaluate the safety of biologics. TNF inhibitors were pooled to perform comparison with placebo and among themselves, calculating odds ratios (OR) with associated 95% credible intervals (CrI), probability of being best (Pbest) and the surface under the cumulative ranking curve (SUCRA) as well as numbers needed to treat (NNT).
Results Twenty-nine double-blind RCTs with 5200 patients were included in the analysis focusing on 6 TNF inhibitors, including etanercept, intended copies of etanercept, adalimumab, infliximab, golimumab and certolizumab. Compared with placebo, TNF inhibitors were efficacious in achieving ASAS20, ASAS5/6, partial remission and BASDAI50 responses, but with an increased risk of AEs and withdrawals due to AEs. No significant differences in efficacy were found among biologics, except that etanercept had a higher rate of ASAS20 response compared with golimumab in the Chinese patients (OR 4.78, 95% CrI 1.20–17.84). Among the Chinese population, etanercept was ranked the most efficacious therapy for ASAS20 with NNT of 2 (Pbest 93.6%, SUCRA 0.97).
Conclusions Compared to placebo, TNF inhibitors are efficacious in controlling disease activity for AS and nr-axSpA patients without a higher risk of severe AEs. Although no significant differences in efficacy among biologics were found, the Chinese population had a better ASAS20 response to etanercept.
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Disclosure of Interest None declared