Background: Tumor necrosis factor (TNF)-blockers are approved for use in several immune-related conditions, but treatment patterns, such as switching between TNF blockers or restarting treatment after a gap in therapy, are not clearly established. This analysis examined TNF blocker treatment patterns within the first year after initiating treatment with etanercept, adalimumab, or infliximab in patients with rheumatoid arthritis, psoriasis, psoriatic arthritis, or ankylosing spondylitis.
Methods: Administrative claims data from the MarketScan® Commercial Claims and Encounters Database (Thomson Reuters, Ann Arbor, MI, USA) were analyzed for patients with rheumatoid arthritis, psoriasis, psoriatic arthritis, or ankylosing spondylitis who were continuously enrolled and newly initiated etanercept, adalimumab, or infliximab treatment between January 1, 2005 and July 1, 2009. Persistence (no treatment gap ≥45 days), restarting index therapy (after a ≥45-day treatment gap), switching to a different biologic of interest (certolizumab, golimumab, ustekinumab, alefacept, abatacept, rituximab, or tocilizumab), and stopping (≥45-day treatment gap with no restart or switch) were analyzed for the first year after the index date.
Results: A total of 8,454 patients had an index claim for etanercept (n = 4,224), adalimumab (n = 2,941), or infliximab (n = 1,289). Treatment patterns in the first year across all four conditions combined for etanercept, adalimumab, or infliximab, respectively, were: persistence, 42%, 47%, and 56%; restarting, 25%, 19%, and 12%; switching, 13%, 12%, and 13%; and stopping, 20%, 22%, and 19%. The combined rates of either persistence or restarting initial therapy after a treatment gap were 67%, 66%, and 68%, for etanercept, adalimumab, and infliximab, respectively. Most switches (66-92%) were between the three TNF blockers.
Conclusion: In the first year after initiating TNF blocker therapy, patients often have a ≥45-day treatment gap; however, approximately two-thirds of patients are either persistent with or restart their index therapy in the year following TNF blocker initiation.