N/A
N=2,776,278
Flublok v. Standard Dose Vaccine Effectiveness Among Kaiser Permanente Northern California Adults 18-64 Years
Influenza · Pneumonia · Lower Respiratory Tract Infection · Acute Myocardial Infarction · Congestive Heart Failure
Bottom Line
View on ClinicalTrials.gov: NCT03694392 ↗Enrolled (actual)
2,776,278
Serious AEs
0.0%
Results posted
Apr 2025
Primary outcome: Primary: Number of Adults 50-64 Years Old With Polymerase-chain Reaction (PCR) Confirmed Influenza Tests — 559; 925 participants — p=<0.05
Study Design & Population
- Study type
- Observational
- Phase
- N/A
- Interventions
- Flublok Quadrivalent (Biological); Standard Dose Inactivated Influenza Vaccine (SD-IIV) (Biological)
- Age
- Adult · 18+ yrs
- Sex
- All
- Sponsor
- Kaiser Permanente
- Primary completion
- Apr 2021
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Number of Adults 50-64 Years Old With Polymerase-chain Reaction (PCR) Confirmed Influenza Tests |
559; 925 | <0.05 sig |
| SECONDARY Number of Adults 50-64 Years Old Hospitalized With PCR-confirmed Influenza |
95; 153 | <0.05 sig |
| SECONDARY Number of Adults 50-64 Years Old Hospitalized With Community-acquired Pneumonia |
106; 183 | <0.05 sig |
| SECONDARY Number of Adults 50-64 Years Old Hospitalized With Cardio-respiratory Events |
631; 890 | <0.05 sig |
| SECONDARY Number of Adults 50-64 Years Old With Polymerase-chain Reaction (PCR) Confirmed Influenza A Tests |
522; 862 | <0.05 sig |
| SECONDARY Number of Adults 50-64 Years Old With Polymerase-chain Reaction (PCR) Confirmed Influenza B Tests |
37; 64 | <0.05 sig |
Summary
The overall objective of this study is to describe the effectiveness of Flublok Quadrivalent vaccine compared to standard dose inactivated influenza vaccine (SD-IIV) in adults 18 through 64 years of age. During this study, Flublok Quadrivalent or SD-IIV will be administered according to the guidelines in the Prescribing Information materials and only to persons for whom it is indicated. The 2018-2019, 2019-2020, and 2020-2021 formulations of recombinant influenza vaccine (Flublok Quadrivalent vaccine) and SD-IIV will be evaluated for outcomes including all polymerase chain reaction (PCR)-confirmed influenza, PCR-confirmed hospitalized influenza, hospitalized community-acquired pneumonia and cardio-respiratory events.
Eligibility Criteria
Inclusion Criteria
- Between the ages of ≥18 and <65 years at the time of influenza vaccination
- Receive either Flublok Quadrivalent vaccine or standard dose inactivated influenza vaccine at a Kaiser Permanente Northern California facility during the study period from August 2018 through April 2020
Exclusion Criteria
- Children <18 years old
- Adults ≥65 years old
Data sourced from ClinicalTrials.gov (NCT03694392). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.