Patient outcomes following therapy switch influenced by patient factors
A Danish study into treatment outcomes in patients with inflammatory arthritis following a treatment switch have indicated that outcomes are affected by patient-related factors and non-specific drug effects.
A study of 2016 patients with inflammatory arthritis has shown that outcomes following a switch in the treatment regimen are affected by patient-related factors and non-specific drug effects. In April 2016, patients receiving from 50 mg originator (ETA) for rheumatoid arthritis (RA) were switched to biosimilar (SB4) etanercept for economic reasons. 1-year treatment outcomes in 2061 patients was studied using data from the DANBIO registry, which covered more than 95% of adults with rheumatic diseases treated in Denmark, according to the study authors.
“Real-world evidence on effectiveness of switching to biosimilar etanercept is scarce,” commented first author Bente Glintborg (Gentofte and Herlev University Hospital, Denmark) in the study and, as such, it was unclear whether this mandated switch may affect patient outcomes and why.
Glintborg explained: “Switch outcomes for the two biosimilars might differ due to different active substances (monoclonal antibodies vs. receptor fusion protein) and increasing experience with, and confidence in, the use of biosimilars in patients and community over time.”
79% of the 2061 patients switched from ETA to SB4, with no change in disease activity and flare rates from 3 months before the switch until 3 months after. After a year, treatment retention rates were lower in switchers and higher in non-switchers, compared with historic retention rates. Rates of withdrawal from SB4 were higher in patients non in remission, although the reasoning was largely subjective.
Biosimilars have the potential to reduce treatment cost as well as increase patient satisfaction, though treatment access and provision of an additional treatment option, but further study is required to confirm the safety, efficacy and long-term outcomes of patients switched to biosimilar drugs.
Source: Glintborg B, Loft AG, Omerovic E et al. To switch or not to switch: results of a nationwide guideline of mandatory switching from originator to biosimilar etanercept. One-year treatment outcomes in 2061 patients with inflammatory arthritis from the DANBIO registry. Ann. Rheum. Dis. 78:192-200 (2019)