(078) Safety of the Janssen COVID-19 vaccine (JCOVDEN) using VAC4EU European Healthcare Data: Methods and Results of the First Study Feasibility Assessment

Publication Number: 415

Background: As part of the lifecycle benefit-risk assessment of vaccines, a post-authorisation safety study (PASS) using real-world data was required by EMA-PRAC to characterise and evaluate the safety of the JCOVDEN.

Objectives: The first phase of the study was a feasibility assessment i) to describe JCOVDEN patterns of use compared to other COVID-19 vaccine brands, ii) to characterise vaccinated individuals, iii) to describe follow–up time and reasons for censoring, and iv) to conduct time-to-onset analyses for 17 selected adverse events of special interest (AESIs).

Methods: This retrospective observational study used electronic healthcare data from two European countries (the Netherlands [PHARMO Data Network] and Spain [VID, SIDIAP]).
A common protocol and the ConcePTION common data model pipeline were used to perform the data management and analyses. The pipeline encompassed the syntactic and semantic harmonisation of data, the implementation of the epidemiological study design, and the statistical analysis.
We report frequencies and percentages, means and standard deviations (SD), medians and interquartile ranges (IQR). The unadjusted incident rates (IRs) per 10,000 person-years of the selected AESIs were calculated and benchmarked to the 2018 background rates published in the ACCESS study.

Results: A total of 527,513 individuals received the first dose of the JCOVDEN. Almost all administration of JCOVDEN occurred in Q2-Q3 2021 (98%). More than 80% of the COVID-19 vaccines administered in 2021 were mRNA vaccines. The relative use of the different COVID-19 vaccine brands was consistent with that reported by the European Centre for Disease Prevention and Control (ECDC). In VID and SIDIAP, JCOVDEN was administered more frequently in individuals aged 40-49 years. Around 55% of JCOVDEN vaccinees were females. Most individuals with a first dose of JCOVDEN received a booster dose with one of the mRNA vaccines about 6 months later. For PHARMO, only vaccine uptake and follow-up data were available for this first feasibility assessment.
In SIDIAP and VID, the unadjusted IRs for most assessed AESIs were consistent with those expected from the background IRs reported in the ACCESS study.

Conclusions: This feasibility analysis showed that the planned PASS is feasible but faces limitations (e.g., the number of persons who received JCOVDEN, channelling of COVID-vaccines over time to different age groups and heterologous schemes) that will be considered by design during the full implementation of the safety study.