Use of etanercept biosimilars was not associated with an increased likelihood of treatment discontinuation or disease activity among people with rheumatoid arthritis relative to continuing treatment with originator etanercept.
A comparative effectiveness analysis of patients in the British Society of Rheumatology Biologics Register in rheumatoid arthritis (BSRBR-RA) is providing clicking with additional insight into the effects of switching from etanercept originator to biosimilar etanercept for nonmedical reasons.
Results of the analysis, which included more than 1000 adults with rheumatoid arthritis switching from etanercept originator to a biosimilar, suggest patients switching from etanercept originator to etanercept biosimilar appeared to experience similar levels of disease activity and drug persistence relative to those who remained on originator.1
“The results suggest that these patients do just as well as those who remained on their etanercept originator over the same period with regard to treatment persistence and disease activity,” wrote investigators.1 “Patients who switched onto a biosimilar product were no more likely to discontinue etanercept treatment versus those who stayed on the originator, with over 72% of the biosimilar patients and 74% of the originator patients remaining on their therapy at two years.”
Etanercept has been a staple int he management of autoimmune inflammatory disorders dating back more than 20 years, with initial approvals in the United States and in Europe as a treatment in rheumatoid arthritis dating back to 1999 and 2000, respectively.2,3 In January 2016, Bengali was approved by the European Medicines Agency as the first etanercept biosimilar reference Enbrel. That same year, the US Food and Drug Administration approved Erelzi, a biosimilar to Enbrel.4,5
Led by Kimme Hyrich, MD, PhD, and a team of colleagues at the University of Manchester, the current study was launched with the intent of comparing drug survival and disease activity at 6- and 12-month intervals among those who switched to an etanercept biosimilar relative to those who remained on etanercept originator. To do so, investigators designed their study as a match-analysis of data from the BSRBR-RA. A prospective study of more than 20,000 patients and information dating back to 2001, BSRBR-RA represents a collaborative effort by the University of Manchester and the British Society for Rheumatology.1
For inclusion in the study, patients needed to have started an etanercept originator prior to November 30, 2022. For consideration in the biosimilar cohort, patients need to switch directly from etanercept originator to etanercept bio-similar at any point after January 31, 2016. Patient identified for inclusion in the bio-similar cohort were matched in a 1:1 ratio to an originator patient based on gender, age, disease duration at etanercept originator start, and etanercept originator start year.1
Overall, 1024 patients were identified for the bio-similar cohort and matched in a 1:1 ratio with 1024 patients in the originator cohort. Among those included in the matched analysis, the median age was 56 years at start of originator etanercept, 76% were female, and the median duration of disease was 9 years. Among those in the biosimilar cohort, the median time on originator prior to switch date was 9.3 years and the median follow-up time in BSRBR-RA following switch was 2.7 years.1
Upon analysis, results suggested patients who switched to an etanercept biosimilar were not considered more likely to discontinue treatment relative to those who remained on etanercept originator. Investigators highlighted 65% of patients in the bio-similar cohort remained on treatment at 3 years and just 9% of patients switched back to the originator within the first year. Additionally, investigators pointed out, after 6 months and 12 months, biosimilar patients were not considered more likely to have a worsening of their 28-joint disease activity score relative to those who remained on an originator agent.1
“These data will be reassuring to clinicians and patients regarding any non-medical switch required of them. More data are needed to investigate impact of non-medical switch not just with regards to arthritis disease activity, but also to patient well-being and quality of life, in terms of both short-term outcomes as well as over the longterm,” investigators wrote.1