The purpose of this study is to describe the safety and immunogenicity of repeat administration of Adacel vaccine approximately 10 years following initial administration of the vaccine. Antibody levels prior to revaccination will also be used to characterize antibody persistence following initial vaccination 10 years earlier. Primary Objectives: * To compare seroprotection rates against tetanus and diphtheria induced by Adacel vaccine to those induced by Td Adsorbed vaccine. * To compare booster response rates against tetanus and diphtheria induced by Adacel vaccine to those induced by Td Adsorbed vaccine. * To compare anti-pertussis geometric mean antibody concentrations (GMCs) induced by Adacel vaccine to the GMCs induced by Daptacel® vaccine given to infants. Secondary Objectives: * To describe the rates of immediate reactions, solicited reactions, unsolicited adverse events (AEs), and serious adverse events (SAEs) following vaccination with Adacel or Td Adsorbed vaccine. * To describe booster response rates for pertussis antigens following revaccination with Adacel vaccine.
Healthy adults \< 65 years of age who received Adacel vaccine 10 years previously will be randomized to receive either Adacel or TENIVAC (Td Adsorbed) vaccine. They will be assessed for immunogenicity at baseline and post-vaccination. Safety data will be collected for 6 months following vaccination.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
SINGLE
Enrollment
1,330
0.5 mL, Intramuscular
0.5 mL, Intramuscular
Unnamed facility
Huntsville, Alabama, United States
Unnamed facility
Jonesboro, Arkansas, United States
Unnamed facility
Little Rock, Arkansas, United States
Unnamed facility
San Diego, California, United States
Unnamed facility
Boulder, Colorado, United States
Unnamed facility
Marietta, Georgia, United States
Unnamed facility
Woodstock, Georgia, United States
Unnamed facility
Peoria, Illinois, United States
Unnamed facility
Mishawaka, Indiana, United States
Unnamed facility
Louisville, Kentucky, United States
...and 23 more locations
Percentage of Participants With Diphtheria and Tetanus Seroprotection
Anti-Diphtheria antibodies were assessed by a toxin neutralization test. Anti-Tetanus antibodies were assessed using an enzyme-linked immunosorbent assay. Seroprotection was defined as the following: Anti-Diphtheria and Anti-Tetanus ≥ 0.1 IU/mL.
Time frame: 1 month post-booster vaccination
Percentage of Participants With Diphtheria and Tetanus Booster Response
Anti-Diphtheria antibodies were assessed by a toxin neutralization test. Anti-Tetanus antibodies were assessed using an enzyme-linked immunosorbent assay. A booster response was defined as a 4-fold increase in pre- to post-vaccination antibody concentrations for subjects with pre-vaccination antibody concentrations ≤2.56 IU/mL for diphtheria and ≤ 2.7 IU/mL for tetanus. If the pre vaccination antibody concentrations were \> 2.56 IU/mL for diphtheria and \> 2.7 IU/mL for tetanus, then a 2-fold increase in response rate was defined as a booster response.
Time frame: 1 month post-booster vaccination
Geometric Mean Concentrations (GMC) of Anti Pertussis Antibodies
Anti-Pertussis antibodies (Pertussis toxoid, Filamentous Hemagglutinin (FHA), Pertactin, Fimbriae types 2 and 3) were assessed using an enzyme-linked immunosorbent assay. Anti-pertussis GMCs further to Adacel vaccination was compared to an historical control group with Daptacel (NCT00255047 for pertussis toxoid and PMID 8538705 for FHA, Pertactin and Fimbriae) since Td Adsorbed Vaccine does not contain any pertussis antigens.
Time frame: 1 month post-booster vaccination
Percentage of Subjects With Pertussis Antigen Booster Response
Anti-Pertussis antibodies (Pertussis toxoid, Filamentous Hemagglutinin \[FHA\], Pertactin, Fimbriae (types 2 and 3) were assessed using an enzyme-linked immunosorbent assay. Booster response is defined as a minimum rise in antibody concentration from pre- to post-vaccination. The minimum rise is at least 2 times if the pre-vaccination concentration is above the cutoff value, or at least 4 times if it is at or below the cutoff value. Anti-pertussis toxoid booster response rates further to Adacel vaccination was compared to an expected booster rates based on study Td506 (PMID 15933223) since Td Adsorbed Vaccine does not contain any pertussis antigens.
Time frame: 1 month post-booster vaccination
Percentage of Participants Reporting a Solicited Injection Site or Systemic Reactions
Injection site reactions: Pain, Erythema, and Swelling. Systemic reactions: Fever (Temperature), Headache, Malaise, and Myalgia. Grade 3 Injection site reactions: Pain, Significant, prevents daily activity. Erythema and Swelling, \>100 mm. Grade 3 Systemic reactions: Fever, ≥39°C or ≥102.1 F; Headache, Malaise, and Myalgia, Significant; prevents daily activity.
Time frame: Day 0 up to Day 7 post-vaccination
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