Mandatory Biosimilar Switch in Canada Has Minimal Impacts on Patient Health

A mandatory switch to biosimilar etanercept had minimal impacts on patient health, according to a Canadian study using rapid monitoring of drug and health services utilization. The study, published in BMC Rheumatology reviewed the results of a mandated switch from originator etanercept (Enbrel) to a biosimilar in British Columbia (BC), Canada, as part of its Biosimilars Initiative.

The BC Biosimilars Initiative is a mandatory biosimilar switching policy in which patients in the PharmaCare prescription coverage plan receiving certain reference drugs are being switched to available biosimilars. New Brunswick, Alberta, and Quebec all have mandatory biosimilar switching programs in place, as well.

There are 2 etanercept biosimilars approved in Canada: Brenzys from Merck, which was approved in August 2016, and Erelzi from Sandoz, which was approved in April 2017.

“Following the recent patent expiration of originator etanercept, the more affordable biosimilar versions of etanercept are available,” the authors wrote. “Switching patients from originator etanercept to its biosimilars as part of routine clinical practice may result in significant public and private drug cost savings.”

The researchers conducted a prospective, population-based cohort study using administrative data from the BC Ministry of Health. The province of BC has a universal health system providing access to physicians and hospital services. PharmaCare, the provinces’ drug plan, covers eligible prescriptions, certain medical supplies, and pharmacy services.

The study included 4 cohorts of patients on the originator etanercept: a policy cohort (n = 1694) of patients who used the originator drug in the 6 months leading up to the launch of the Biosimilars Initiative and 3 historical cohorts of patients who refilled a prescription for the originator in the 6 months before May 27 in 2016 (n = 1878), 2017 (n = 1963), and 2018 (n = 1823). Patients in the historical cohorts were consider controls.

The researchers found:

• Prescriptions for etanercept biosimilars increased from 17.3% in May 2019 to 96.9% in December 2019
• 65.1% of patients had switched to a biosimilar by the end of the 6-month transition period
• 88.1% of patients had switched by the end of the 1-year follow-up period
• 9.6% of patients in the policy cohort switched to a different biologic disease-modifying antirheumatic drug (bDMARD) by the end of the 1-year follow up, which was similar to switching trend in the historical cohorts (between 8.2% and 9.7%)
• There was a transient increase in etanercept refills between months 3 and 8
• The switching policy had no impact on emergency department visits or admissions

The ability to monitor changes in health services utilization so quickly was a strength of the study, and the researchers noted that they provided policy makers with monthly reports that had just a 1-month lag. A limitation of the study is the lack of a way to control for differences between cohorts.

“We did not find permanent unintended changes in health services utilization, which suggests that switching to the biosimilar etanercept had minimal impacts on patient health,” the authors concluded. “Additional research on clinical outcomes is recommended to strengthen the evidence that no long-term unintended negative health impacts are associated with switching from originator etanercept to its biosimilars.”

Reference

Fisher A, Kim JD, Carney G, Dormuth C. Rapid monitoring of health services use following a policy to switch patients from originator to biosimilar etanercept-a cohort study in British Columbia. BMC Rheumatol. Published online January 27, 2022. doi:10.1186/s41927-021-00235-x