Using Data from the Canadian Post-marketing Spontaneous Pharmacovigilance System for Drug Safety Research: A Feasibility Study.

Introduction: Post-marketing studies involve the detection and interpretation of potential problems associated with the use of a given drug. Post-marketing spontaneous pharmacovigilance systems, such as the Canada Vigilance program, may constitute a gold mine of free data for drug safety research. However, the quantity and the quality of data remain to be demonstrated.

Objective: To assess the feasibility to use the Canada Vigilance database for academic drug safety research, and to document the characteristics of data that are extractable.

Methods: This is a descriptive retrospective analysis study design. The beta-blocker and anticoagulant adverse reactions (AR) in Canada were analyzed. Tests for data extraction from the Canada Vigilance database were performed in October 2019; data were then available from January 1, 1966 to June 30, 2019.

Results: There were 41 variables with extractable data. For anticoagulants, data were extracted in Excel and.pdf file format, while it was only plain text.pdf files for beta-blockers. Overall, there were 4707 reported ARs with the use of anticoagulants and 6332 cases reported for beta-blockers. The trend of ARs related to anticoagulants steadily increased in the study period, with a notable increase in 2009 while direct oral anticoagulants were marketed. The proportion of missing data varied from 0 to 98%, but most important variables were all available. It was not possible to distinguish brand names and generic drugs in the database.

Conclusion: It seems feasible to use data from the Canadian Post-marketing Spontaneous Pharmacovigilance System for academic drug safety research. Upcoming studies should validate the quality of reports compared to actual medical charts.