NCT06029933

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

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

• Status: Recruiting
• Phase: —
• Study type: Observational
• Enrollment: 960,000 (estimated)
• Sponsor: Kaiser Permanente · Academic / Other
• Sex: All
• Age: 65 Years
• Healthy volunteers: Accepted

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.

Conditions

• Influenza
• Community-acquired Pneumonia
• Cardiovascular Events

Interventions

Type	Name	Description
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.
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.

Timeline

• Start date: 2023-08-17
• Primary completion: 2025-05-01
• Completion: 2026-05-01
• First posted: 2023-09-08
• Last updated: 2023-09-08

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study