Persistence of biological agents over an eight-year period in rheumatoid arthritis and spondyloarthritis patients.

Objective: To calculate the persistence, over a period of eight years, the retention rate of first and second-line of treatment with biological agents in  patients with rheumatoid arthritis, spondyloarthritis and psoriatic arthritis and to compare retention rates of the various drugs for each pathology.

Method: Retrospective observational study that included patients affected by  rheumatoid arthritis, spondyloarthritis and psoriatic arthritis, who started  treatment with biological agents between January 2009 and December 2012 and followed until December 2016.

Results: 132, 87 and 33 patients were included in rheumatoid arthritis, spondyloarthritis and psoriatic arthritis, respectively. The median  retention duration of all biological agents for the first and second-line, was 30.9 months and 14.0 months, respectively for rheumatoid arthritis; 63.06  months and 25.6 months, respectively in spondyloarthritis. Psoriatic arthritis did  not reach the median (> 70 months in first-line) (first line p = 0.002). Individual drug survival in first line: the median retention duration of tocilizumab was 58.3 months, followed by etanercept (p = 0.79) in rheumatoid arthritis. For spondyloarthritis, golimumab and etanercept had greater retention than the other drugs (they did not reach the median): adalimumab was 63.0 months and for infliximab was 50.1 months. In psoriatic arthritis, golimumab,  infliximab and etanercept not reach the median and they had greater retention than adalimumab (59.4 months). Individual drug survival in second  line: tocilizumab was the most persistent drug (median 22.1 months) in  rheumatoid arthritis, and golimumab for spondyloarthritis and psoriatic arthritis.

Conclusions: Tocilizumab and etanercept in rheumatoid arthritis, and golimumab in spondyloarthritis and psoriatic arthritis also, were the most persistent drugs in first-line and second-line treatment.