The US-CDC implemented V-Safe to monitor COVID-19 vaccines, and the EMA-funded vACcine COVID-19 monitoring readinESS ACCESS project created template protocols for cohort event monitoring which were made publicly available in February 2021. In Europe the ACCESS protocols were implemented in the Early Covid Vaccine Monitor (ECVM) study which included first vaccinated persons, this study was continued and complemented by the COVID-19 Vaccine Monitor cohort event monitoring study (CVM), which focused on special populations and booster vaccinations, and included additional countries. Cohort event monitoring is an active safety surveillance tool that can be used to collect solicited and unsolicited adverse reactions following COVID-19 vaccination, with two objectives: i) to generate, estimate, describe, and compare incidence rates of patient-reported Adverse Drug Reactions (ADRs) of the different COVID-19 vaccines across the participating countries in the general and special populations (pregnant and lactating women, children, and adolescents, immunocompromised, people with history of allergy, and people with prior SARS-CoV-2 infection), and ii) to identify and generate incidence rates and potential predictors of the most frequently reported ADRs related to different COVID-19 vaccines after the first/second dose(s) of the first vaccination cycle as well.

The research leading to these results was conducted as part of the activities of the EU PE&PV (Pharmacoepidemiology and Pharmacovigilance) Research Network (led by Utrecht University) with collaboration from the Vaccine Monitoring Collaboration for Europe network (VAC4EU). The project has received support from the European Medicines Agency under the Framework service contract nr EMA/2018/23/PE. This report expresses the opinion of the authors and may not be understood or quoted as being made on behalf of or reflecting the position of the European Medicines Agency or one of its committees or working parties. The work in this report is based on: EU PAS Register No: WP1: EUPAS42504 WP2: EUPAS39798