Carmona L and Gómez-Reino JJ (2006) Survival of TNF antagonists in spondylarthritis is better than in rheumatoid arthritis. Data from the Spanish registry BIOBADASER. Arthritis Res Ther 8: R72

The tumor necrosis factor (TNF) inhibitors infliximab, etanercept and adalimumab are commonly used in the treatment of both spondyloarthritis and rheumatoid arthritis (RA); however, long-term efficacy and safety data exist only for RA. A new study, based on data from the Spanish drug registry BIOBADASER, has compared the duration of treatment and safety profiles of these three TNF inhibitors in spondyloarthritis and rheumatoid arthritis.

Carmona and Gómez-Reino compared the rates of treatment discontinuation and adverse events in spondyloarthritis patients (n = 1,524) and RA patients (n = 4,006), respectively. At 1, 2 and 3 years, they found that duration of treatment was markedly longer in spondyloarthritis than in RA. The hazard ratio for discontinuation of treatment among spondyloarthritis patients (compared with RA patients) was 0.66 (95% CI 0.57–0.76). In addition, adverse events were less common in spondyloarthritis patients: only 17% of spondyloarthritis patients experienced an adverse event, compared to 26% of RA patients (P <0.001). The hazard ratio for adverse events in spondyloarthritis patients was 0.80 (95% CI 0.70–0.91).

The authors conclude that TNF-inhibitor therapy is safe and effective in spondyloarthritis; indeed, these agents have a better safety profile and longer duration of treatment when used to treat spondyloarthritis than when used to treat RA. As spondyloarthritis requires chronic treatment, however, assessment of outcomes beyond 3 years is recommended.