Fluad vs. Fluzone High-Dose Vaccine Effectiveness Among Adults ≥65 Years
Study Details
Study Description
Brief Summary
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 and 2024/25 influenza seasons. The study is an observational study conducted at Kaiser Permanente Northern California (KPNC), an integrated health care system in the United States.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
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Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Fluad Recipients Kaiser Permanente Northern California members aged ≥65 years who receive Adjuvanted Quadrivalent Inactivated Influenza Vaccine (aIIV4) |
Biological: Adjuvanted Quadrivalent Inactivated Influenza Vaccine (aIIV4)
Fluad Quadrivalent vaccine is an inactivated influenza vaccine formulated to contain 60 mcg of hemagglutinin (HA) total, with 15 mcg from each of the four recommended influenza strains and the MF59 adjuvant in single-dose prefilled 0.5 mL syringes. Kaiser Permanente Northern California members ≥65 years may receive Fluad as part of routine clinical care during the influenza season.
Other Names:
|
| Fluzone High-Dose Recipients Kaiser Permanente Northern California members aged ≥65 years who receive High-Dose Quadrivalent Inactivated Influenza Vaccine (HD-IIV4) |
Biological: High-Dose Quadrivalent Inactivated Influenza Vaccine (HD-IIV4)
Fluzone High-Dose Quadrivalent vaccine is an inactivated split virion influenza vaccine formulated to contain 240 mcg of HA total, with 60 mcg from each of the four recommended influenza strains in single-dose prefilled 0.7 mL syringes. Kaiser Permanente Northern California members ≥65 years may receive Fluzone High-Dose as part of routine clinical care during the influenza season.
Other Names:
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Outcome Measures
Primary Outcome Measures
- PCR-confirmed influenza [≥14 days after vaccination until date of outcome, death, loss-to-follow-up, or end of each season (estimated May 2024 or May 2025)]
KPNC members ≥65 years who receive Fluad or Fluzone High-Dose will be retrospectively assessed for the presence of PCR-confirmed influenza. This outcome will be assessed in single-season analyses (2023/24 and 2024/25 separately) and a pooled 2-seasons analysis (2023/24 and 2024/25 combined).
Secondary Outcome Measures
- Emergency department visit or hospitalization for PCR-confirmed influenza [≥14 days after vaccination until date of outcome, death, loss-to-follow-up, or end of each season (estimated May 2024 or May 2025)]
KPNC members ≥65 years who receive Fluad or Fluzone High-Dose will be retrospectively assessed for an emergency department visit or hospitalization for PCR-confirmed influenza. This outcome will be assessed in single-season analyses (2023/24 and 2024/25 separately) and a pooled 2-seasons analysis (2023/24 and 2024/25 combined).
- Hospitalization for PCR-confirmed influenza [≥14 days after vaccination until date of outcome, death, loss-to-follow-up, or end of each season (estimated May 2024 or May 2025)]
KPNC members ≥65 years who receive Fluad or Fluzone High-Dose will be retrospectively assessed for hospitalization for PCR-confirmed influenza. This outcome will be assessed in a pooled 2-seasons analysis (2023/24 and 2024/25 combined).
- Hospitalization for all-cause community-acquired pneumonia [≥14 days after vaccination until date of outcome, death, loss-to-follow-up, or end of each season (estimated May 2024 or May 2025)]
KPNC members ≥65 years who receive Fluad or Fluzone High-Dose will be retrospectively assessed for hospitalization for all-cause community-acquired pneumonia. This outcome will be assessed in single-season analyses (2023/24 and 2024/25 separately) and a pooled 2-seasons analysis (2023/24 and 2024/25 combined).
Other Outcome Measures
- Hospitalization for cardiovascular events [≥14 days after vaccination until date of outcome, death, loss-to-follow-up, or end of each season (estimated May 2024 or May 2025)]
KPNC members ≥65 years who receive Fluad or Fluzone High-Dose will be retrospectively assessed for hospitalization for cardiovascular events. This outcome will be assessed in single-season analyses (2023/24 and 2024/25 separately) and a pooled 2-seasons analysis (2023/24 and 2024/25 combined).
- PCR-confirmed influenza in subgroups with comorbidities [≥14 days after vaccination until date of outcome, death, loss-to-follow-up, or end of each season (estimated May 2024 or May 2025)]
KPNC members ≥65 years with comorbidities (e.g., cardiovascular and respiratory conditions, diabetes, obesity) who receive Fluad or Fluzone High-Dose will be retrospectively assessed for hospitalization for PCR-confirmed influenza. This outcome will be assessed in a pooled 2-seasons analysis (2023/24 and 2024/25 combined).
Eligibility Criteria
Criteria
Inclusion Criteria:
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Age ≥65 years at the time of influenza vaccination
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KPNC member at the time of vaccination
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Receive either aIIV4 or HD-IIV4 at a KPNC facility during the 2023/24 and/or 2024/25 influenza seasons
Exclusion Criteria:
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Age <65 years at the time of influenza vaccination
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Received either aIIV4 or HD-IIV4 in the inpatient setting
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Receive more than one influenza vaccination during a single season period (i.e., 2023/24 or 2024/25 influenza seasons)
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Receive an influenza vaccination outside of KPNC
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Kaiser Permanente Northern California (entire region) | Oakland | California | United States | 94612 |
Sponsors and Collaborators
- Kaiser Permanente
- Seqirus
Investigators
None specified.Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- 2033496