Enhanced Passive Safety Surveillance (EPSS) confirms an optimal safety profile of the use of MF59® -adjuvanted influenza vaccine in older adults: Results from three consecutive seasons.

Donatella Panatto,Sylvie Tomczyk,Mendel Haag,Daniela Amicizia,Maria Maddalena Lino,Piero Luigi Lai

doi:10.1111/irv.12685

Abstract

BackgroundIn Europe, the enhanced safety surveillance (ESS) of seasonal influenza vaccines is mandatory, in order to detect any potential increase in reactogenicity when the vaccine composition is updated. The MF59®‐adjuvanted influenza vaccine (Fluad™) is the first and the only licensed adjuvanted seasonal influenza vaccine in Europe.ObjectiveOur objective was to summarize the safety data of Fluad™ over three consecutive seasons.MethodsA passive approach to ESS (EPSS) was adopted, in which reporting of spontaneous adverse events (AEs) by vaccinees and vaccine exposure was estimated, in order to generate a near real‐time reporting rate. EPSS was conducted in Italy during the 2015, 2016, and 2017 influenza seasons in the primary care setting. All AEs reported within 7 days following immunization were analyzed by season, type and seriousness. Fisher's exact test was used to compare frequencies between seasons.ResultsTotal exposure accounted for approximately 1,000 doses of Fluad™ for each season. A total of 0.5% (2015), 0.7% (2016), and 0.5% (2017) individual case safety reports (ICSRs) were received, corresponding to a total of 9 (2015), 18 (2016), and 12 (2017) spontaneous AEs. The frequencies of AEs of interest were below those expected on the basis of the known safety profile of the vaccine. Most AEs were mild‐to‐moderate in severity. No between‐season difference was found.ConclusionsOur analyses confirmed that the safety data observed were consistent with the known safety profile of Fluad™, which has been amply established over the last 20 years. No significant changes in the safety profile were observed.

Highlights

In Europe, the enhanced safety surveillance (ESS) of seasonal influenza vaccines is mandatory, in order to detect any potential increase in reactogenicity when the vaccine composition is updated
In the overall population, reports of any unsolicited adverse events (AEs) decreased by 35% [adjusted risk ratio, adjuvanted vs unadjuvanted: 0.65]
This report is the first to provide an overview of spontaneous individual case safety reports (ICSRs) received from vaccinees with FluadTM in three consecutive influenza seasons in the context of Enhanced passive safety surveillance (EPSS)

Summary

| BACKGROUND

The prevention, monitoring, and control of adverse events (AEs) following immunization are essential to ensuring safety and main‐ taining public confidence in vaccines; without the latter it is almost impossible to achieve optimal vaccination coverage.[1]. FluadTM was first licensed in 1997 in Italy; since 81 million doses have been administered worldwide.[5] It is currently authorized for the immunization of people aged 65 years or older in about 30 countries, while in Canada a pediatric formulation indicated for children aged 6‐23 months is available.[6]. With regard to solicited AEs, these were reported more frequently in subjects immunized with adjuvanted formulations than in those who received non‐adjuvanted vaccine. Most of these AEs involved the injection site were of mild/ moderate intensity and resolved in a few days.[20]. The secondary objective was to compare the observed frequen‐ cies between seasons

| METHODS

| Ethics statement

Findings

| DISCUSSION