Background Incidence Rates of Selected Vaccine Adverse Events of Special Interest in Canada

Study summary

No information provided.

Study identification

• EU PAS number:
  EUPAS1000001053
• Study ID:
  1000001053
• Official title and acronym:
  Background Incidence Rates of Selected Vaccine Adverse Events of Special Interest in Canada
• DARWIN EU® study:
  No
• Study countries:
  Canada
• Study description:
  The COVID-19 pandemic highlighted the need for timely detection of emerging safety signals for new vaccines and continuous lifecycle monitoring for established vaccines. Background incident rates of adverse events of special interest (AESIs) can facilitate the identification of vaccine safety signals using observed-to-expected analyses. Such analyses were conducted globally in response to safety concerns arising during the COVID-19 vaccine rollout. In Canada, evidence on background incidence rates of AESIs is currently limited to the provinces of British Columbia and Ontario, highlighting the need for national data. As part of a collaboration with the International Coalition of Medicine Regulatory Authorities (ICMRA), CNODES will replicate a DARWIN EU study (EUPAS1000000254) to estimate background incidence rates for selected vaccine AESIs in Canada.; ; We will conduct a descriptive retrospective cohort study using administrative health databases from 6 provinces. The analysis will be conducted separately for pediatric and adult populations. The study population will include all eligible individuals who were registered for provincial medical services coverage between January 1, 2015, and December 31, 2024 (or the latest date of data availability). We will study the incidence of 5 AESI categories including: Guillain-Barré Syndrome, myocarditis, encephalitis, stroke, and thrombocytopenia; with no prior record of the specific outcome within a 365-day washout window. Incidence rates per 100,000 person-years will be estimated for each AESI. Rates will be stratified by subgroups and will also be age and sex standardized to the European and Canadian populations. Demographic and clinical characteristics of individuals with incident AESIs will be described and compared with individuals without the AESIs matched on age, sex, and calendar time of the event. Three sensitivity analyses will be conducted. Results will be reported by province separately and pooled across provinces.
• Study status:
  Ongoing

Research institutions and networks

Institutions

Lady Davis Institute

University of British Columbia

University of Calgary, Calgary, Canada;
University of Manitoba, Winnipeg, Canada;
Dalhousie University, Halifax, Canada;
ICES, Toronto, Canada;
Saskatchewan Health Quality Council, Saskatoon, Canada

Networks

Canadian Network for Observational Drug Effect Studies (CNODES)

Canada

Study timelines

Date when funding contract was signed

Actual:10/11/2025

Study start date

Actual:10/11/2025

Date of final study report

Planned:05/03/2027

Sources of funding

Other

More details on funding

CNODES is a collaborating core network partner of CoLab, which is funded for query-related activity by Canada’s Drug Agency (CDA-AMC, grant number C222 360).

Regulatory

• Was the study required by a regulatory body?:
  Yes
• Is the study required by a Risk Management Plan (RMP)?:
  Not applicable