Predictive clinical-genetic model of long-term non-response to tumor necrosis factor-alpha inhibitor therapy in spondyloarthritis.

AIM: Tumor necrosis factor inhibitors (TNFi) are effective in controlling disease activity in spondyloarthritis (SpA). However, in a proportion of patients these treatments are ineffective or lead to adverse events. Recently, alternative therapies, such as interleukin (IL)-17 or IL-23 inhibitors, have emerged in the treatment of these pathologies. This study aimed to determine clinical and genetic predictors of non-response to TNFi treatment in 118 spondyloarthritis patients diagnosed according to Assessment in SpondyloArthritis International Society (ASAS) criteria.

METHOD: From the literature, 41 single nucleotide polymorphisms (SNPs) were selected that had previously been associated with TNFi treatment response in spondyloarthropathies, rheumatoid arthritis and psoriasis. A clinical non-response was defined as a decrease of <50% of initial Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) in axial involvement, or a reduction of less than 1.2 of initial Disease Activity Score of 28 joints-C-reactive protein (DAS28-CRP) in patients with only peripheral involvement. Univariate and multivariate hazard ratios (HR) were determined using Cox proportional hazard models to analyze the potential prognostic factors affecting non-response to TNFi treatment.

RESULTS

The clinical factors that significantly increased the non-response rate were: global visual analog scale (VAS), CRP, BASDAI, Bath Ankylosing Spondylitis Functional Index (BASFI), and the number of TNFi used. Only rs11591741 SNP showed an association with non-response. In the multivariate analysis, females had a non-response rate 4.46 times higher than males; each one-point increase in the BASFI index increased the non-response rate by 75%, and being a genotype GG vs GC or CC carrier was associated with an almost 4 times greater non-response rate.

CONCLUSION

We developed a clinical-genetic model to identify SpA patients with a long-term non-response to TNFi therapy.