Apply to trial NCT06029933

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RecruitingBiological intervention

Fluad vs. Fluzone High-Dose Vaccine Effectiveness Among Adults ≥65 Years

This study will evaluate the relative vaccine effectiveness of quadrivalent adjuvanted inactivated influenza vaccine (aIIV4) versus quadrivalent high-dose inactivated influenza vaccine (HD-IIV4) in preventing polymerase chain reaction (PCR)-confirmed influenza and influenza-related outcomes in adults ≥65 years of age during the 2023/24, 2024/25, and 2026/27 influenza seasons. The study is an observational study conducted at Kaiser Permanente Northern California (KPNC), an integrated health care system in the United States.

How this works

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    About 5 to 10 minutes. Skip-friendly where possible.

  2. We connect you with the study team

    When a site picks up your application, we introduce you to their team directly — with you on the thread.

  3. The team reaches out to schedule screening

    Usually within a few business days, via the contact you give.

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