A Study to Assess Tolerability of the Trivalent Recombinant Vaccine in Individuals Aged 18 and Older Using the Vaccinees Perception of Injection Questionnaire

This study will be conducted through an online survey that respondents will complete only if they meet the inclusion criteria and give their consent to continue to the main questionnaire. Each participant will complete the survey only once. Participants will provide details about their demographic data, health status, perceptions of flu vaccination and injection site reactions, as well as drivers for vaccine choice and future vaccine use.

In the 2024-2025 influenza season, the sponsor conducted a feasibility study to evaluate patient-reported severity, impact and tolerability of RIV3 local and systemic symptoms, as well as the overall experience of participants with vaccination. The study employed two validated instruments: the EQ-5D-5L and the VAPI , targeting participants aged 18 to 64 years.

For the 2025-2026 influenza season, the study sponsor intends to enhance participant enrollment to enable the generation of statistically robust and clinically meaningful data on the tolerability profile of RIV3. The resulting data are intended for dissemination through peer-reviewed scientific journals and presentation at international scientific conferences.