Influenza is a serious public health problem that is mostly preventable with immunization. Recommendations for influenza vaccine composition are changed on an annual basis, necessitating ongoing benefit-risk assessment. From September 1 to November 30, 2016, researchers conducted near-real-time enhanced passive surveillance (EPS) for the influenza vaccine Fluarix Tetra in ten volunteer general practices in England that used Fluarix Tetra as their primary influenza vaccine brand, in accordance with European Medicines Agency guidelines. The EPS approach combined normally obtained data from electronic health records with a customized adverse event reporting card (AERC) issued to Fluarix Tetra vaccine recipients. Data for individuals who received a different influenza vaccination were obtained only from the EHR. They reported the weekly and cumulative incidence of pre-defined adverse events of interest (AEI) that occurred within 7 days after vaccination, after adjusting for the clustering effect. Of the 97,754 eligible individuals, 19,334 were vaccinated against influenza, with 13,861 receiving Fluarix Tetra. A total of 1,049 Fluarix Tetra participants reported AEIs, including 703 using the AERC. Individual pre-specified AEI categories analysis revealed no safety indication for Fluarix Tetra. An AEI was reported by 62 people who received a recognized brand of non-GSK influenza vaccination and 54 people who received an unknown brand.
In conclusion, the study found no safety signal for Fluarix Tetra and demonstrated that the AERC was a valuable tool that supplemented regular pharmacovigilance by enabling more extensive AEI collection.
Reference: https://www.tandfonline.com/doi/full/10.1080/21645515.2019.1565258