Comparison of the Safety of Flublok® Versus Licensed IIV in Healthy, Medically Stable Adults ≥ 50 Years of Age

Comparison of the Safety of Flublok® Versus Licensed Inactivated Influenza Vaccine in Healthy, Medically Stable Adults ≥ 50 Years of Age

The hypothesis for this trial is that the incidence of a pre-defined composite of common systemic hypersensitivity adverse events for Flublok recipients is non-inferior to that reported for licensed IIV recipients. Another hypothesis is that the safety and reactogenicity of Flublok is clinically acceptable, i.e. consistent with the overall safety profiles previously observed with Flublok and with the licensed comparator.

The Advisory Committee on Immunization Practices (ACIP) recommends that all people aged 6 months and older be immunized to prevent influenza. Currently the only approved influenza vaccine across the entire age group is inactivated influenza vaccine (IIV). A Biologics Licensing Application (BLA) for Flublok was approved by the FDA for influenza immunization of adults 18-49 years of age. Additional safety and, ultimately efficacy, data is needed to support use in adults ≥50 years of age, an important age group as adults ≥65 years of age are among those at increased risk of influenza complications.

Inclusion Criteria:

1. Ambulatory adults aged 50 years and older
2. Medically stable, as determined by medical history and targeted physical examination based on medical history, if appropriate
3. Able to understand and comply with planned study procedures
4. Provides written informed consent prior to initiation of any study procedure.

Exclusion Criteria:

1. Known contraindication to either study vaccine (see product package inserts)
2. Receipt of any other influenza or other vaccine within 30 days prior to enrollment in this study.
3. Receipt of any new medication within 30 days prior to enrollment in this study
4. Plans to participate in any investigation involving an investigational product during this study.
5. Pre-existence of atopic dermatitis or any other cutaneous disorder that could complicate the evaluation of potential primary endpoints.
6. Any clinical or social circumstance that in the opinion of the investigator could interfere with compliance with study procedures or interfere with the interpretation of clinical data.