Drug survival of anti-tumour necrosis factor α therapy in spondyloarthropathies: Results from the Spanish emAR II study

Abstract

Objective. To assess drug survival and the reasons for switching anti-TNF-α therapy in SpA patients in a Spanish nationwide study. Methods. A cross-sectional study was performed. Sample size was calculated to represent all regions and hospitals throughout the country. Demographic data, patient characteristics and disease activity parameters were obtained. Drug survival and reasons for switching anti-TNF therapy were also recorded. Results. A total of 467 SpA patients receiving at least one anti-TNF agent were identified. Among patients who received a first, second and third anti-TNF course, 39.4%, 37.4% and 23.1% discontinued treatment, respectively. The main reasons for switching anti-TNF agents in the first course were lack or loss of efficacy (LOE) and adverse events (AEs) in 40% and 30% of switchers, respectively. Similarly, reasons for switching during the second anti-TNF course were LOE in 48% and AEs in 28% of switchers. Of the 467 SpA patients starting anti-TNF therapy, 28% switched to a second and 8% switched to a third therapy. Mean drug survival for the first, second and third anti-TNF courses were 84.4 (95% CI 78.4, 90.5), 70.2 (95% CI 61.6, 78.9) and 64.8 (95% CI 51.1, 78.5) months, respectively (P = 0.315).Conclusion. Twenty-eight per cent of SpA patients starting anti-TNF therapy switched to a second anti-TNF agent. Drug survival did not differ among anti-TNF courses. The main reason for switching anti-TNF therapy was LOE. Switchers were more frequently women and had higher disease activity parameters at the time of the study than non-switchers.