A study to evaluate the Safety, Tolerability, and Immunogenicity of an Investigational Tetanus/Diphtheria/Pertussis Booster Vaccine (Tdap-1018) Compared to Boostrix in Healthy Volunteers Between 10 and 22 Years of Age

INTERVENTION: The study will be conducted in 2 parts: • Part 1 will enroll healthy adult volunteers 18 to 22 years of age, inclusive. Part 1 will consist of approximately 24 subjects in 2 escalating dose levels of CpG(Tdap)‐1018 (Group A: 1500 mcg; Group B: 3000 mcg) with approximately12 subjects in each group (Tdap 1018 n = 8; Boostrix n = 4). • Part 2 will enroll healthy adolescent volunteers 10 to 17 years of age, inclusive. Part 2 will consist of approximately 250 subjects in 2 escalating dose levels of CpG(Tdap)‐1018 (Group C: 1500 mcg; Group D: 3000 mcg) with approximately 125 subjects (Tdap 1018 n = 100; Boostrix n = 25) in each group. All subjects will receive 1 dose of their assigned treatment (Tdap 1018 Dose 1, Tdap‐1018 Dose 2, or Boostrix). All subjects will undergo assessments of safety and immunogenicity. Subjects will be followed for safety for 12 weeks after the study injection. All subjects will have a pre‐vaccination blood draw and receive the assigned treatment vaccine at Day 1. Blood draws for measuring post‐vaccination antibody levels and exploratory evaluations will be done at Week 4. Safety assessments will be done at Weeks 4 and 12. CONDITION: Infection ‐ Other infectious diseases Pertussis;Diptheria;Tetanus; ; Pertussis ; Diptheria ; Tetanus Respiratory ‐ Other respiratory disorders / diseases PRIMARY OUTCOME: To evaluate the safety and tolerability of Tdap‐1018. This is a composite outcome.[; This is a composite primary outcome where each component is assessed by monitoring the following parameters through Week 12 or End of Study/Early Discontinuation.; Parameters:; 1. Incidence of local and systemic post‐injection reactions (PIRs); 2. Incidence of serious adverse events (SAEs); 3. Incidence of adverse events (AEs) leading to treatment discontinuation; ; PIRs, AEs and SAEs will be graded based on the United States Food and Drug Administration’s (FDA) Guidance for Industry: Center for Biologics Evaluation and Research (CBER) Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trials.] SECONDARY OUTCOME: To assess the immunogenicity to pertussis of Tdap‐1018 compared with Boostrix 4 weeks after a booster vaccination[This is a composite secondary outcome. Each component is assessed by obtaining blood samples at the following timepoints: Day 1(prior to study vaccine injection), Day 4 and End of Study visit. ; Parameters: ; 1. Geometric mean concentration (GMC) of antibodies to each of the pertussis antigens 4 weeks after dosing: anti‐pertussis toxin (anti‐PT), anti‐ filamentous hemagglutinin (anti‐FHA), and anti‐pertactin (anti‐PRN). ; 2. Booster response rates for antibodies to pertussis antigens (inactivated pertussis toxin [PT], filamentous hemagglutinin [FHA], and pertactin [PRN]): ; ‐ In initially seronegative subjects (threshold to be defined), post‐vaccination antibody concentrations greater than or equal to 4 × threshold. ; ‐ In initially seropositive subjects with pre‐vaccination antibody concentrations between greater than or equal to threshold and 4 × threshold, an increase of greater than or equal to 4 × the pre‐vaccination antibody concentration. ; ‐ Ratio of GMCs of antibodies to pertussis antigens comparing Tdap 1018 with Boostrix. ; Parameters: ; 1. Booster response rates for anti‐tetanus (anti‐T) and anti‐diphtheria (anti D) antibodies: ; ‐ In subjects with pre‐vaccination less than 0.1 IU/mL, post‐vaccination concentration greater than or equal to 0.4 IU/mL ; ‐ In subjects with pre‐vaccination concentration greater than or equal to 0.1 IU/mL, an increase of at least 4 times the pre‐vaccination concentration. ; ; 2. Percentage of subjects with (anti‐T) antibodies greater than or equal to 0.1 IU/mL ; ‐ In initially seropositive subjects with pre‐vaccination antibody concentrations greater than 4 × threshold, an increase of greater than or equal to 2 × the pre‐vaccination antibody concentration ; ‐ Geometric mean fold increase of anti‐PT, anti‐FHA, and anti‐PRN (Day 29 versus Day 1)] To assess the immunogenicity to tetanus and diphtheria for Tdap‐1018 compared with Boostrix 4 weeks after a booster vaccination[This is a composite secondary outcome. Each component is assessed by obtaining blood samples at the following timepoints: Day 1(prior to study vaccine injection), Day 4 and End of Study visit. ; 3. Percentage of subjects with anti‐T antibodies greater than or equal to 1.0 IU/mL ; 4. Percentage of subjects with (anti‐D) antibodies greater than or equal to 0.1 IU/mL ; 5. Percentage of subjects with anti‐D antibodies greater than or equal to 1.0 IU/mL ; 6. GMCs of anti‐T and anti‐D antibodies.] INCLUSION CRITERIA: A subject must meet all of the following criteria to be eligible for enrollment (defined as receiving any study vaccine) in the study: 1) Willing to participate: pediatric assent and written parental/legal guardian consent; or adult informed consent provided for the study 2) Male or female, 18 to 22 (Part 1) or 10 to 17 (Part 2) years of age 3) Have documentation of 2 or more prior acellular pertussis (aP) vaccinations 4) Be in good health in the opinion of the investigator, based upon medical history, physical examination (adults), and laboratory evaluation (adults) 5) Adult subject, or adolescent subject and/or adult guardian of adolescent subject, be able to comprehend and follow all required study procedures and be available for all visits scheduled in the study 6) Seronegative for human immunodeficiency virus (HIV), adults only