Oral Presentation: Analyzing the U.S. Post-Marketing Safety Surveillance of COVID-19 Vaccines

Background/Introduction: Since December 2020, three COVID-19 vaccines have been authorized in the United States (U.S.) and were proceeded by large immunization programs. Objective/Aim: The aim of this study was to characterize the U.S. post-marketing safety (PMS) profiles of these vaccines with an indepth analysis of mortality data. Methods: This was a retrospective database analysis study. Details of the U.S. PMS reports (15 December 2020 to 19 March 2021) of the three vaccines (Pfizer-BioNTech, Moderna, and Janssen Ad26.COV2.S) were retrieved from the U.S. Vaccine Adverse Event Reporting System (VAERS). A descriptive analysis was conducted to characterize the reported adverse events (AEs). A comparative (Pfizer-BioNTech vs. Moderna) analysis of mortality was conducted. The mean count ratio of death between the two vaccines was estimated using a negative binomial regression model adjusting for the measured confounders. Results: A total of 44,451 AE reports were retrieved (corresponding to 0.05% of the vaccinated U.S. population at least one dose). The initial estimated reporting rates for AEs in the US were 37.5 cases 100,000 of all doses administered (15 December 2020 to 19 March 2021). The median age in the identified reports was 49 years, and more than two-third of patients were female (73.9%). The most frequently reported AEs (per total number of AE reports) were pain (35.3%), injection site reactions (27.0%), headache (18.6%), fatigue (13.0%), and pyrexia and dizziness (10%, respectively). Serious AEs were reported in only 6,514 (14.6%) of the reports with 4,108 hospitalizations. The total number of death reports was 1,919, and the median age at death was 80 years. Of the death cases, 38.4% (737) had a history of a cardiovascular disease, 16.3% had diabetes, 13% had a respiratory disease and 9.7% had renal disease. The mean count ratio of Moderna (n = 997) vs. Pfizer-BioNTech (n = 899) of 1.07 (95% confidence interval 0.86 to 1.33). Conclusion: The vast majority of PMS AEs in the U.S. were nonserious, and the number of serious AEs is very low given the total number of vaccinated U.S. population. No differences in the mortality findings between Moderna and Pfizer-BioNTech were observed.