Monitoring the safety of Efluelda Tetra vaccine in older adults

Post-marketing Surveillance Study for the Safety of Efluelda Tetra Pre-filled Syringe, a High-dose Quadrivalent Influenza Vaccine Administered to Adults 65 Years or Older in the Republic of Korea.

Observational Sanofi · NCT06694025

This study is testing the safety of the Efluelda Tetra vaccine in adults aged 65 and older to see how well it works in real-life situations.

Quick facts

Study typeObservational
Enrollment670 (estimated)
Ages65 Years and up
SexAll
SponsorSanofi Industry-sponsored
Locations1 site (Seoul)
Trial IDNCT06694025 on ClinicalTrials.gov

What this trial studies

This observational study aims to assess the safety profile of the Efluelda Tetra pre-filled syringe vaccine in adults aged 65 years and older. Participants will be monitored for adverse events and adverse drug reactions following vaccination under routine clinical practice. The study will last approximately 28 to 35 days, with a possible extension if follow-up visits are missed. The goal is to gather real-world data on the vaccine's safety in this age group.

Who should consider this trial

Good fit: Ideal candidates for this study are adults aged 65 years or older who are receiving the Efluelda Tetra vaccine.

Not a fit: Patients who have previously participated in this study or are currently involved in other clinical studies related to vaccines or drugs may not benefit.

Why it matters

Potential benefit: If successful, this study could provide valuable insights into the safety of the Efluelda Tetra vaccine for older adults, enhancing vaccination strategies.

How similar studies have performed: Other studies have successfully monitored vaccine safety in older populations, indicating that this approach is well-established.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Adults aged 65 years or older on the day of enrollment
* The informed consent form has been signed and dated
* Receipt of 1 dose of Efluelda Tetra on the day of enrollment according to the approved local product label

Exclusion Criteria:

* Previous history of enrollment in this study
* Participation at the time of study enrollment (or in the 4 weeks preceding the enrollment) or planned participation during the present study period in a clinical study investigating a vaccine, drug, medical device or medical procedure

Where this trial is running

Seoul

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions ImmunizationInfluenza
Last reviewed 2026-06-10 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.