Post-Marketing Observational Study of Safety Following Vaccination With Flublok® Compared to Licensed IIV in Adults

Study Overview
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Brief Summary
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The primary objective of this study is to retrospectively characterize the safety of Flublok in adults 18 years of age and older, in comparison with egg-based trivalent or quadrivalent inactivated influenza vaccines (IIVs), using a methodological approach designed to query the database of electronic health records (EHR) maintained by Kaiser-Permanente, Northern California (KPNC), a large medical care organization (MCO).

Detailed Description
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The primary analysis is a nonrandomized, observational retrospective cohort study. Data on adults 18 years of age and older who were enrolled in the KPNC database during the risk intervals after vaccination analyzed for this study who were vaccinated with Flublok or an IIV (either IIV3 or IIV4) will be identified for analysis. The rates of occurrence of specific MAEs of interest in pre-specified risk intervals following Flublok and IIV will be compared.

Official Title
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Post-Marketing Observational Study of Safety Following Vaccination With Flublok® Compared to Licensed IIV in Adults 18 Years of Age and Older

Conditions
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Human Influenza

Intervention / Treatment
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* Biological: Recombinant Influenza Vaccine
* Biological: Inactivated Influenza Vaccine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Data from the EHR of all adult KPNC members 18 years of age and older, who received Flublok for active immunization against influenza as part of routine medical care within the KPNC system. The comparator cohort will include data from all adults in the same age group who received any IIV (trivalent or quadrivalent) during the period of Flublok administration. Exclusion Criteria: Healthcare providers are expected not to administer Flublok or IIV to individuals with known contraindication to either vaccine (see product package inserts). However, there will be no exclusions other than age and KPNC membership criteria at the time of vaccination.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Flublok<br>Recombinant influenza vaccine (RIV); Intramuscular injection of vaccine of recombinant uncleaved hemagglutinin (rHA0) derived from influenza A/H1N1, A/H3N2, and B viruses, as identified for the season by the FDA Vaccines and Related Biological Products Advisory Committee (VRBPAC) in a total volume of 0.5 mL. | Biological: Recombinant Influenza Vaccine<br>* Intramuscular injection of study vaccine<br>* Other names: Flublok;|
| Inactivated Influenza Vaccine<br>Injectable, inactivated, egg-based influenza vaccines (IIV); Intramuscular injection of vaccine (whether trivalent or quadrivalent) derived from influenza A/H1N1, A/H3N2, and B viruses, as identified for the season by the FDA Vaccines and Related Biological Products Advisory Committee (VRBPAC) in a total volume of 0.5 mL. | Biological: Inactivated Influenza Vaccine<br>* Intramuscular injection of study vaccine<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants with Serious adverse events (SAEs) and medically-attended adverse events (MAEs) | Incidence of Serious and/or Medically-Attended Adverse events | Five months post-vaccination |