The purpose of this study is to demonstrate the efficacy of an investigational Vero cell-derived, trivalent, seasonal influenza vaccine to prevent infection with an influenza virus that is antigenically similar to one of the three strains in the vaccine. Subjects will be randomized in a double-blind fashion to receive a single intramuscular injection of either the investigational vaccine or placebo. Blood will be drawn from all subjects for a determination of hemagglutination inhibition antibody titers on Days 0 and 21, body temperature and injection site reactions will be monitored daily for 7 days. In addition, subjects must return to the clinic promptly to have swab samples of their nose and throat taken whenever they feel flu symptoms and all subjects will be monitored for adverse events until Day 180.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
DOUBLE
Enrollment
7,250
Single intramuscular injection
Single intramuscular injection
Quality of Life Medical & Research Center, LLC
Tucson, Arizona, United States
Benchmark Research
Sacramento, California, United States
California Research Foundation
San Diego, California, United States
Benchmark Research San Francisco
San Francisco, California, United States
Radiant Research, Inc
Denver, Colorado, United States
Efficacy of an Investigational Vero Cell-derived Influenza Vaccine to Prevent Infection With an Influenza Virus That is Antigenically Similar to One of the Three Strains in the Vaccine
The number of subjects developing influenza infection, as confirmed by viral culture and typing of naso-pharyngeal specimens, with a virus that is antigenically similar to one of the strains contained in the vaccine 21 days to 180 days after the date of vaccination.
Time frame: 180 days
Number of Subjects Who Developed Influenza Infection 21 Days to 180 Days Post-vaccination With Infecting Strain Matching the Strains Contained in the Vaccine
Number of subjects with influenza infection confirmed by viral culture and typing and/or RT-PCR analysis of naso-pharyngeal specimens that are antigenically similar to the strains contained in the vaccine
Time frame: 180 days
Number of Subjects Who Developed Influenza Infection Between 21 and 180 Days Post-vaccination, Regardless of Whether the Infecting Strain Matched the Vaccine Strains Antigenically
Number of subjects with influenza infection as confirmed by viral culture and typing of naso-pharyngeal specimens regardless of whether the isolate is antigenically matched to the strains contained in the vaccine
Time frame: 180 days
HIA Titer for Each of the Three Antigens Contained in the Vaccine at Day 21
Time frame: 21 days
Percentage of Subjects With Seroprotective Antibody Titer [Reciprocal HIA Titer ≥ 40] for Each of the Three Antigens Contained in the Vaccine at Day 21
Time frame: 21 days
Fold Increase of HIA Titer for Each of the Three Antigens Contained in the Vaccine at Day 21 as Compared to Baseline
Time frame: 21 days
Percentage of Subjects Demonstrating Seroconversion to Each of the Three Antigens Contained in the Vaccine at Day 21
Seroconversion is defined as a ≥ 4-fold increase in HIA titer from baseline or a HIA titer ≥ 40 when there is no detectable HIA titer (HIA titer \<10) at baseline.
Time frame: 21 days
Frequency and Severity of Occurrence of Any Injection Site Reactions Related to Vaccination
Number of Subjects With Non-Serious Local Reactions During the Entire Follow-Up Period
Time frame: 180 days
Frequency and Severity of Occurrence of Any Injection Site Reactions and Systemic AEs Observed During the Entire 180-day Follow-up Period
Time frame: 180 days
Frequency and Severity of Occurrence of Any Systemic Reactions Related to Vaccination
Number of Subjects With Non-Serious Systemic Reactions During the Entire Follow-Up Period
Time frame: 180 days
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Clinical Research of South Florida
Coral Gables, Florida, United States
Jacksonville Center for Clinical Research
Jacksonville, Florida, United States
Pharmax Research Clinic
Miami, Florida, United States
University Clinical Research, Inc
Pembroke Pines, Florida, United States
Miami Research Associates
South Miami, Florida, United States
...and 26 more locations