Outpatient Nirmatrelvir-Ritonavir and Remdesivir Utilization in Canada

Outpatient Nirmatrelvir-Ritonavir and Remdesivir Utilization in Canada

Outpatient Nirmatrelvir-Ritonavir and Remdesivir Utilization in Canada

HC0069

Overview

What is the issue?
  • Nirmatrelvir-ritonavir and remdesivir are two antiviral therapies indicated for the treatment of non-hospitalized adult patients with mild to moderate COVID-19.
  • The Public Health Agency of Canada is currently responsible for overseeing the procurement and allocation of these drugs to ensure their availability for federal, provincial, and territorial health care systems. Gathering information on the outpatient utilization of these therapies is needed to help determine fair access in the future.
What was the aim of the study?
  • This drug utilization study aimed to describe the use of nirmatrelvir-ritonavir and remdesivir in the outpatient setting across Canadian provinces for which data were readily available, and to describe the characteristics of patients receiving these therapies.
How was the study conducted?
  • This study was a collaboration with ADTEC and INESSS.
  • Nirmatrelvir-ritonavir:
    • We used administrative health databases from the provinces of Alberta, British Columbia, Manitoba, Ontario, Quebec, and Saskatchewan.
    • Monthly outpatient prescriptions and patient characteristics were studied.
  • Remdesivir:
    • As outpatient remdesivir infusions are not routinely captured in prescription drug claims, we obtained aggregate data for outpatient remdesivir prescriptions from the provinces of Ontario and Saskatchewan, and the greater Winnipeg area in Manitoba.
    • Monthly outpatient prescriptions at the provincial level were studied.
What did the study find?
  • Nirmatrelvir-ritonavir use:
    • Overall, 212,593 adults filled 218,862 nirmatrelvir-ritonavir prescriptions during the study period (which ranged from January 2022 to June 2023).
    • More than 90% received only one course of treatment, and less than 10% were dispensed the recommended lower dosage for renal impairment.
    • Monthly use per population was highest in Manitoba and Ontario, with rapid growth in the first year, and lower and more stable use in other provinces. The trend changed when expressed by the number of COVID-19 cases.
    • Approximately 70% of nirmatrelvir-ritonavir recipients were aged 65 years and older, and more than 90% received at least 1 dose of a COVID-19 vaccine, although there were important cross-provincial differences in patient characteristics.
  • Remdesivir use:
    • A total of 2,610 outpatient remdesivir prescriptions were recorded from July 2022 to May 2023 in Ontario, 324 from April 2022 to April 2023 in Saskatchewan, and 407 from April 2022 to May 2023 in Winnipeg, Manitoba.
    • Expressed per unit population, trends in monthly remdesivir utilization were similar. In all provinces, monthly use grew rapidly, peaking in early fall 2022 and declining thereafter.
    • Patient characteristics are unknown, as only aggregate data were readily available.
Implications
  • To our knowledge, this is the first population-based analysis of nirmatrelvir-ritonavir and remdesivir utilization in Canada.
  • Our study included data from 6 provinces, and findings may not be generalizable to other jurisdictions.
Key messages
  • Outpatient nirmatrelvir-ritonavir use varied across provinces. Remdesivir use, in the provinces for which utilization data was available, was low overall.
  • Utilization of both therapies gradually decreased from October 2022, suggesting declining demand in this patient setting.

Manuscripts

Presentations

Project Team

Project Lead
Michael Paterson MSc
Research Assistant
Audray St-Jean MSc
Site Investigator
Donica Janzen PhD
Saskatchewan
Site Investigator
Mike Benigeri
Quebec
Site Investigator
Michael Paterson MSc
Ontario
Site Investigator
Alan Katz MBChB, MSc, CCFP
Manitoba
Site Investigator
Colin R. Dormuth ScD
British Columbia
Site Investigator
Paul Ronksley PhD
Alberta
Analyst
Xinya Lu PhD
Saskatchewan
Analyst
Jean-Luc Kaboré
Quebec
Analyst
Houssem Missaoui
Quebec
Analyst
Fangyun Wu MSc
Ontario
Analyst
Ruby Sheng
Ontario
Analyst
Matthew Dahl BSc
Manitoba
Analyst
Sylvia Aponte-Hao
Alberta