Comparing two flu vaccines for older adults
Relative Vaccine Effectiveness of Adjuvanted Quadrivalent Inactivated Influenza Vaccine vs High-Dose Quadrivalent Inactivated Influenza Vaccine Among Adults ≥65 Years for the 2023-24 and 2024-25 Seasons
This study is testing which of two flu vaccines works better for adults aged 65 and older to prevent the flu and related health issues.
Quick facts
| Study type | Observational |
|---|---|
| Enrollment | 960000 (estimated) |
| Ages | 65 Years and up |
| Sex | All |
| Sponsor | Kaiser Permanente Academic / other |
| Locations | 1 site (Oakland, California) |
| Trial ID | NCT06029933 on ClinicalTrials.gov |
What this trial studies
This observational study evaluates the effectiveness of two types of influenza vaccines, the quadrivalent adjuvanted inactivated influenza vaccine (aIIV4) and the quadrivalent high-dose inactivated influenza vaccine (HD-IIV4), in preventing confirmed influenza and related health outcomes in adults aged 65 and older. Conducted at Kaiser Permanente Northern California, the study will analyze data from the 2023/24 and 2024/25 influenza seasons. Participants will be KPNC members who receive one of the vaccines at a KPNC facility during the specified seasons.
Who should consider this trial
Good fit: Ideal candidates are adults aged 65 years and older who are members of Kaiser Permanente and receive either aIIV4 or HD-IIV4 during the study period.
Not a fit: Patients under 65 years of age or those receiving their vaccination outside of Kaiser Permanente will not benefit from this study.
Why it matters
Potential benefit: If successful, this study could help identify the more effective vaccine for preventing influenza and its complications in older adults.
How similar studies have performed: Previous studies have shown varying effectiveness of different influenza vaccines in older populations, making this approach relevant and potentially impactful.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Age ≥65 years at the time of influenza vaccination * KPNC member at the time of vaccination * Receive either aIIV4 or HD-IIV4 at a KPNC facility during the 2023/24 and/or 2024/25 influenza seasons Exclusion Criteria: * Age \<65 years at the time of influenza vaccination * Received either aIIV4 or HD-IIV4 in the inpatient setting * Receive more than one influenza vaccination during a single season period (i.e., 2023/24 or 2024/25 influenza seasons) * Receive an influenza vaccination outside of KPNC
Where this trial is running
Oakland, California
- Kaiser Permanente Northern California (entire region) — Oakland, California, United States (Recruiting)
Study contacts
- Study coordinator: Amber H. Hyman, PhD, MPH
- Email: Amber.Hyman@kp.org
- Phone: 510-267-7571
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.