The aim of the study was to investigate the immunogenicity and safety of CYD dengue vaccine and Tetanus Toxoid (T), Reduced Diphtheria Toxoid (D) and Acellular Pertussis Vaccine Adsorbed (ap) (Tdap) vaccine when both vaccines were administered concomitantly or sequentially. Primary Objectives: * To demonstrate the non-inferiority of the humoral immune response to the Tdap booster dose concomitantly administered with the first dose of CYD dengue vaccine as compared to sequential administration, measured 28 days after Tdap booster dose. * To demonstrate the non-inferiority of the humoral immune response to the first dose of CYD dengue vaccine concomitantly administered with Tdap as compared to sequential administration, measured 28 days after the first dose of CYD dengue vaccine. Secondary Objectives: * To demonstrate the non-inferiority of the humoral immune response of 3 doses of CYD dengue vaccine with the first dose concomitantly administered with Tdap as compared to sequential administration, measured 28 days after the third dose of CYD dengue vaccine. * To describe the humoral immune response at baseline and 28 days after the first and third doses of CYD dengue vaccine, in each and any group. * To describe the humoral immune response of Tdap vaccine at baseline and 28 days after concomitant administration with the first dose of CYD dengue vaccine as compared to the sequential administration, in each and any group. * To describe the safety of the CYD dengue vaccine and of the Tdap booster dose after each and any injection in each group.
Participants were to receive CYD dengue vaccine according to a 3-dose schedule administered 6 months apart, with the first dose of CYD dengue vaccine administered either concomitantly or sequentially with a booster dose of the Tdap vaccine, Adacel®. During the conduct of the study, a safety signal was identified which led to the Independent Data Monitoring Committee (IDMC) recommendation not to vaccinate participants who had never been infected by dengue prior to the first injection, i.e., dengue non-immune participants. The protocol was amended accordingly but never implemented due to absence of response of Health Authorities (HA) from The Philippines. After having waited for more than 1.5 years, and as the participants became out of window to complete their immunization schedule and the last safety follow-up call (6 months after the last dose), the Sponsor decided to stop the trial. Participants only attended a last safety follow-up visit to terminate the study and were informed about the end of the study. As a consequence, the study was prematurely terminated before injection of the last dose (3rd dose) of the CYD dengue vaccine. As a consequence of the IDMC recommendations, the main immunogenicity analyses were done in dengue immune participants which is not what was planned in the protocol (and this is why the primary endpoints are not exactly the same as those defined in the protocol as they were finally assessed only in dengue immune participants whereas initially it was planned to be assessed regardless of baseline status). All participants were assessed for immunogenicity and safety. Safety assessments included solicited reactions within 7 or 14 days after each injection, unsolicited adverse events within 28 days after each injection, and serious adverse events during the study period.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
NONE
Enrollment
688
0.5 milliliter (mL), Subcutaneous at Month 1, 7 and Month 13, respectively
0.5 mL, intramuscularly (IM) at Month 1.
0.5 mL, intramuscularly at Day 0.
Unnamed facility
City of Muntinlupa, Alabang, Philippines
Unnamed facility
Manila, Philippines
Unnamed facility
Quezon, Philippines
Unnamed facility
Quezon City, Philippines
Geometric Mean Concentrations (GMCs) of Antibodies Against Pertussis Antigens (Pertussis Toxoid, Filamentous Hemagglutinin, Pertactin, and Fimbriae 2+3) 28 Days After Dose of Tdap Vaccine in Previously Dengue Immune Participants
GMCs against each pertussis antigens (pertussis toxoid \[PT\], filamentous hemagglutinin \[FHA\], pertactin \[PRN\], fimbriae types 2 and 3 \[FIM2+3\]) were assessed using an enzyme-linked immunosorbent assay (ELISA) method and were measured in ELISA unit/milliliter (EU/mL). Dengue immune participants at Baseline were defined as participants with titers \>=10 (1/dilution) for at least one serotype with the parental dengue virus strain.
Time frame: 28 days after Tdap vaccination
Percentage of Participants With Seroprotection Against Diphtheria and Tetanus Antigens 28 Days After the Dose of Tdap Vaccine in the Previously Dengue Immune Participants
Seroprotection against diphtheria (Anti-D) and tetanus (Anti-T) antigens was performed by Micrometabolic Inhibition Test - Toxin Neutralization assay (MIT-TNA) and ELISA, respectively. Seroprotection was defined as anti-D and anti-T Ab concentration greater than 0.1 international units (IU)/mL. Dengue immune participants at Baseline were defined as participants with titers \>=10 (1/dilution) for at least one serotype with the parental dengue virus strain.
Time frame: 28 days after Tdap vaccination
Geometric Mean Titers (GMTs) of Antibodies Against Each Dengue Virus Serotype 28 Days After the First Dose of CYD Dengue Vaccination in the Previously Dengue Immune Participants
The GMTs against each of the four parenteral dengue virus serotypes (1, 2, 3 and 4) of CYD dengue vaccine were assessed using the 50% plaque reduction neutralization test (PRNT50) assay method. Dengue immune participants at Baseline were defined as participants with titers \>=10 (1/dilution) for at least one serotype with the parental dengue virus strain. Titers were measured in terms of 1/dilution.
Time frame: 28 days after first CYD dengue vaccination
Geometric Mean Titers of Antibodies Against Each Dengue Virus Serotype at Baseline and 28 Days After the First Dose of CYD Dengue Vaccination in the Previously Dengue Immune Participants
The GMTs against each of the four parenteral dengue virus serotypes (1, 2, 3 and 4) of CYD dengue vaccine were assessed using PRNT50 assay method. Dengue immune participants at Baseline were defined as participants with titers \>=10 (1/dilution) for at least one serotype with the parental dengue virus strain. Titers were measured in terms of 1/dilution.
Time frame: Baseline (Pre-CYD vaccination 1) and 28 days after the first CYD dengue vaccination
Percentage of Participants With Neutralizing Antibody Titers Against Each of the 4 Dengue Virus Serotypes of CYD at Baseline and 28 Days After First Dose of CYD Dengue Vaccination in the Previously Dengue Immune Participants
The GMTs against each of the four parenteral dengue virus serotypes (1, 2, 3 and 4) of CYD dengue vaccine were assessed using PRNT50 assay method. Dengue immune participants at Baseline were defined as participants with titers \>=10 (1/dilution) for at least one serotype with the parental dengue virus strain.
Time frame: Baseline (Pre-CYD vaccination 1) and 28 days after the first CYD dengue vaccination
Percentage of Participants With Neutralizing Antibody Titers Above Predefined Thresholds Against at Least 1, 2, 3, or 4 Serotypes of CYD at Baseline and 28 Days After the First Dose of CYD Dengue Vaccination in the Previously Dengue Immune Participants
Dengue neutralizing antibody levels against each of the 4 dengue virus serotypes (1, 2, 3, and 4) were measured by PRNT50. Dengue immune participants at Baseline were defined as participants with titers \>=10 (1/dilution) for at least one serotype with the parental dengue virus strain. Percentage of participants with neutralizing antibody titers above pre-defined thresholds (\>=10 and \>=100 \[1/dilution\]) against at least 1, 2, 3, or 4 serotypes of CYD were reported. Here, 'dil'=dilution and "vac"=vaccination in the specified categories.
Time frame: Baseline (Pre-CYD vaccination 1) and 28 days after the first CYD dengue vaccination
Geometric Mean Concentrations of Serum Antibodies Against Pertussis Antigens (Pertussis Toxoid, Filamentous Hemagglutinin, Pertactin, and Fimbriae 2+3) at Baseline and 28 Days After the Dose of Tdap Vaccine in the Previously Dengue Immune Participants
GMCs against each pertussis antigens (PT, FHA, PRN, FIM2+3) were assessed using ELISA assay method and were measured in EU/mL. Dengue immune participants at Baseline were defined as participants with titers \>=10 (1/dilution) for at least one serotype with the parental dengue virus strain.
Time frame: Baseline (Pre-Tdap vaccination) and 28 days after the Tdap vaccination
Percentage of Participants Achieving Serum Antibody (>=0.1 IU/mL) Against Diphtheria and Tetanus Antigens at Baseline and 28 Days After the Dose of Tdap Vaccine in the Previously Dengue Immune Participants
The GMC against diphtheria and tetanus antigens was performed by MIT-TNA and ELISA, respectively. Dengue immune participants at Baseline were defined as participants with titers \>=10 (1/dilution) for at least one serotype with the parental dengue virus strain.
Time frame: Baseline (Pre-Tdap vaccination) and 28 days after the dose of Tdap vaccination
Number of Participants With Immediate Unsolicited Adverse Events (AE) Following Vaccination With Tdap or CYD Dengue Vaccine
An unsolicited AE was an observed AE that did not fulfill the conditions prelisted in the electronic case report form (eCRF) in terms of diagnosis and/or onset post-vaccination. Any unsolicited AE occurred during first 30 minutes post-vaccination was recorded on the CRF as immediate AE. At Visit 1, participants of Group 1 received no vaccination and participants of Group 2 received only Tdap vaccination. At Visit 2, participants of Group 1 received both CYD and Tdap vaccination and participants of Group 2 received only CYD vaccination. At Visit 4, participants of Groups 1 and 2 received CYD vaccination.
Time frame: Within 30 minutes after any and each vaccination
Number of Participants With Solicited Injection Site Reactions Following Vaccination With Tdap or CYD Dengue Vaccine
A solicited reaction (SR) was an AE observed and reported under the conditions (symptom and onset) prelisted (i.e., solicited) in the eCRF and considered as related to vaccination. Solicited injection site reactions included pain, erythema, and swelling. At Visit 1, participants of Group 1 received no vaccination and participants of Group 2 received only Tdap vaccination. At Visit 2, participants of Group 1 received both CYD and Tdap vaccinations and participants of Group 2 received only CYD vaccination. At Visit 4, participants of Groups 1 and 2 received only CYD vaccination.
Time frame: Within 7 days after any and each vaccination
Number of Participants With Solicited Systemic Reactions Following Vaccination With Tdap or CYD Dengue Vaccine
A SR reaction was an AE observed and reported under the conditions (symptom and onset) prelisted (i.e., solicited) in the CRF and considered as related to vaccination. Solicited injection site reactions included fever, headache, malaise, myalgia, and asthenia. At Visit 1, participants of Group 1 received no vaccination and participants of Group 2 received only Tdap vaccination. At Visit 2, participants of Group 1 received both CYD and Tdap vaccinations and participants of Group 2 received only CYD vaccination. At Visit 4, participants of Groups 1 and 2 received only CYD vaccination.
Time frame: Within 14 days after any and each vaccination
Number of Participants Reporting Unsolicited Adverse Events Following Vaccination With Tdap or CYD Dengue Vaccine
An unsolicited AE was an observed AE that did not fulfill the conditions prelisted in the eCRF in terms of diagnosis and/or onset post-vaccination. At Visit 1, participants of Group 1 received no vaccination and participants of Group 2 received only Tdap vaccination. At Visit 2, participants of Group 1 received both CYD and Tdap vaccinations and participants of Group 2 received only CYD vaccination. At Visit 4, participants of Groups 1 and 2 received CYD vaccination.
Time frame: Within 28 days after any and each vaccination
Number of Participants Reporting Non-serious Adverse Event of Special Interests (AESIs) Following Vaccination With Tdap or CYD Dengue Vaccine
Non-serious AESIs were non-serious AEs that were considered by the Sponsor to be relevant for the monitoring of the safety profile of the investigational vaccine. At Visit 1, participants of Group 1 received no vaccination and participants of Group 2 received only Tdap vaccination. At Visit 2, participants of Group 1 received both CYD and Tdap vaccinations and participants of Group 2 received only CYD vaccination. At Visit 4, participants of Groups 1 and 2 received CYD vaccination.
Time frame: Within 7 days post any and each vaccination
Number of Participants Reporting Serious Adverse Events (SAEs) and Serious AESIs Following Vaccination With Tdap or CYD Dengue Vaccine
SAEs were AEs resulting in any of the following outcomes or deemed significant for any other reason: death; life-threatening; required hospitalization or prolonged existing hospitalization; persistent or significant disability/incapacity; congenital anomaly or a medically important event. Serious AESIs were SAEs that were considered by the Sponsor to be relevant for the monitoring of the safety profile of the investigational vaccine.
Time frame: From Day 0 up to 6 months after the last Tdap or CYD vaccination
Number of Participants Reporting Cases of Virologically Confirmed Dengue (VCD) Hospitalization Following Vaccination With Tdap or CYD Dengue Vaccine
Hospitalized suspected dengue case was defined as an acute febrile illness with diagnosis of dengue requiring hospitalization (with bed attribution). In such cases, 1 unplanned acute blood sample (within the first 5 days after fever onset) was collected for virological confirmation of hospitalized suspected dengue case. A suspected case was considered VCD if there was a detection of wild type dengue virus by dengue non-structural protein 1 antigen ELISA and/or dengue reverse transcriptase-polymerase chain reactions.
Time frame: From Day 0 up to 6 months after the last Tdap or CYD vaccination
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