BACKGROUND: The COVID-19 mRNA vaccine (Comirnaty®) received conditional marketing authorisation in December2020 in the European Union and United Kingdom (UK) and standard marketing authorisation inSeptember 2022. Efficient and timely monitoring of the use and safety of the vaccine is needed.
OBJECTIVES: To present vaccine utilisation patterns of Comirnaty from an ongoing post-authorisation safety study thatevaluates the risks of selected adverse events of special interest (AESIs) following vaccination in thegeneral European population.
METHODS: This retrospective cohort study includes patients vaccinated with Comirnaty and matched unvaccinatedindividuals from five European countries using six data sources from the Vaccine monitoringCollaboration for Europe (VAC4EU) association: the Netherlands (PHARMO), Italy (Pedianet), Spain(EpiChron-IACS; SIDIAP), UK (CPRD Aurum), and Norway (Norwegian health registers [NHR]). Recordedprescription, dispensing or administration data from electronic healthcare records were used to assessComirnaty vaccination status based on a distributed methodology with common protocol, theConcePTION common data model and common analytical programs.
RESULTS: Overall, 13,943,561 individuals received ≥1 dose of Comirnaty: PHARMO 1,015,120; NHR 3,552,508 (all upto 31 Dec 21); EpiChron-IACS 729,978 (as of 31 Jan 22); SIDIAP 3,105,320 (as of 30 Dec 21); CPRD 3,596,213(as of 15 Oct 21); and Pedianet 4,921 (as of 28 Feb 22). Among these, 11,634,073 (83%) received a 2nddose of Comirnaty, 2,920,232 (21%) received a 3rd dose of Comirnaty, and 3,220 (0.02%) received a 4thdose of Comirnaty up to the dates mentioned in each database. The median time between the 1st and2nd dose ranged from 3 weeks in EpiChron-IACS to 10 weeks in CPRD. The mean age in vaccinatedindividuals at 1st dose ranged from 46 years (CPRD) to 51 years (NHR).
CONCLUSIONS: The Comirnaty vaccine has been administered widely in the five European countries that contribute datato this study. Based on the data analysed, the majority of vaccinated persons received the completeprimary series (i.e. two-dose immunisation) and 20% received a third dose. The median time betweendose 1 and dose 2 was particularly long in the CRPD, possibly due to UK’s national vaccination programtarget of vaccinating as many individuals as possible with at least 1 dose. Few individuals have received a4th dose within the study period; however, the study will continue to monitor vaccine utilisation throughthe end of the study in December 2023.