Immunogenicity and Safety of a Tetanus-diphtheria Vaccine and a 13-valent Pneumococcal Conjugate Vaccine

Study Overview
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Brief Summary
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When two or more vaccines are administered concurrently, there is a concern on vaccine interaction, which can either enhance or suppress immune response to vaccine antigens. This study is designed to evaluate the immunogenicity and safety of tetanus-diphtheria (Td) and pneumococcal vaccines after concomitant administration in adults aged 50 years and older.

Detailed Description
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Vaccination would be the most effective strategy to prevent diverse infectious diseases. Actually, The World Health Organization (WHO) estimate that vaccination averts 2-3 million deaths per year. In adults, several vaccines are recommended based on age and medical conditions if they have not receive vaccination before, and lack evidence of past infection: influenza, measles-mumps-rubella (MMR), varicella, human papilloma virus (HPV), tetanus-diphtheria (Td), pneumococcl vaccines and etc. In particular, when the patient visits a vaccination clinic, Td and the pneumococcal vaccines are commonly administered at the same time. In this study, we aimed to evaluate the immunogenicity and safety of Td vaccine and PCV13 after concomitant administration in adults aged 50 years. This single-center, open label randomized trial was conducted (Clinical Trial Number - NCT02215863) at Korea University Guro Hospital from November 2013 to April 2016. Adults ≥50 years of age were randomized in a 1:1:1 ratio to receive Td + PCV13 (Group 1), PCV13 alone (Group 2) or Td alone (Group 3).

Official Title
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Immunogenicity and Safety of a Tetanus-diphtheria Vaccine and a 13-valent Pneumococcal Conjugate Vaccine After Concomitant Vaccination in ≥50-year-old Adults

Conditions
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Tetanus, Diphtheria, Pneumococcal Infections

Intervention / Treatment
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* Biological: Tetanus-diphtheria (Td) and PCV13
* Biological: PCV13 alone
* Biological: Td alone


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults aged ≥50 years who signed the informed consent Exclusion Criteria: history of S. pneumoniae infection within the previous 5 years previous pneumococcal vaccination previous tetanus-diphtheria (Td) vaccination within the last 10 years known immunodeficiency or immunosuppressant use or coagulation disorders

Ages Eligible for Study
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Minimum Age: 50 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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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Tetanus-diphtheria (Td) and PCV13<br> | Biological: Tetanus-diphtheria (Td) and PCV13<br>* 154 concomitant Td-PCV13 recipients: one dose of each vaccine administered on Day 0<br>|
| Active Comparator: PCV13 alone<br> | Biological: PCV13 alone<br>* 154 PCV13 recipients: one vaccine injection administered on Day 0<br>|
| Active Comparator: Td alone<br> | Biological: Td alone<br>* 437 Td recipients: one vaccine injection administered on Day 0<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Tetanus antibody titers at day 28 post-vaccination | IgG antibody titers by enzyme linked immunosorbent assay (ELISA) Seroprotection rate: percentage of subjects with a post-vaccination antibody levels ≥0.1 IU/mL | 4 weeks after vaccination | 
| Diphtheria antibody titers at day 28 post-vaccination | IgG antibody titers by enzyme linked immunosorbent assay (ELISA) | 4 weeks after vaccination | 
| Tetanus seroprotection rate at day 28 post-vaccination | Proportion of IgG antibody titers ≥0.1 IU/mL | 4 weeks after vaccination | 
| Diphtheria seroprotection rate at day 28 post-vaccination | Proportion of IgG antibody titers ≥0.1 IU/mL | 4 weeks after vaccination | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Opsonophagocytic assay (OPA) titers for PCV13 | Four capsule serotypes: 1, 5, 18C and 19A | 4 weeks after vaccination |