Tdap Vaccine in Post-Partum Women

Phase IV, Open Label Trial to Evaluate Immunogenicity of Tdap Vaccine in Post-Partum Women to Optimize Vaccination Schedule for Women Who May Have a Subsequent Child

Status

Completed

Phases

Phase 4

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT01711645

Enrollment

Registered

2012-10-22

Start date

2012-10-26

Completion date

2015-08-28

Last updated

2017-05-05

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Diphtheria, Pertussis, Tetanus

Keywords

Acellular, Adacel®, Diptheria toxoids, Pertussis, postpartum, Tdap, Tetanus, women

Brief summary

Monitoring immune response and longevity in serum and milk after Tdap administration to postpartum women. The clinical trial will involve women (aged 18 - 45 years) who have just delivered full-term infants (greater than or equal to 37 completed weeks of gestation) at Vanderbilt University Medical Center. The enrollment period will be fifteen months. The duration is over two years of observation.

Detailed description

This is a single site, prospective study involving only one intervention, receipt of a single 0.5 mL intramuscular (IM) dose of Adacel (Tetanus toxoid, reduced diphtheria toxoid and acellular Pertussis) vaccine, among 55 healthy post partum women. The purpose of the study is to examine the immune responses and subsequent decline in serum and breast milk antibody titers over two years of observation. The clinical trial will involve women (aged 18 - 45 years) who have just delivered full-term infants (greater than or equal to 37 completed weeks of gestation) at Vanderbilt University Medical Center. One particular population at Vanderbilt to target will be the centering prenatal care group that has breastfeeding rates as high as 75 percent at hospital discharge and maintained at 20 percent at 6 months. The enrollment period will be fifteen months. The subjects, staff assessing subjects, and laboratory personnel will be aware of receipt of the vaccine. Since only a single vaccine product is being utilized, there is no blinding needed of the subjects or staff.

Interventions

BIOLOGICALTetanus toxoid, reduced diphtheria toxoid and acellular pertussis vaccine adsorbed onto aluminum phosphate

55 postpartum subjects receive a single intramuscular (IM) 0.5 mL dose of Adacel® (Tetanus toxoid, reduced diphtheria toxoid and acellular pertussis vaccine adsorbed).

Study design

Allocation

Intervention model

SINGLE_GROUP

Primary purpose

PREVENTION

Eligibility

Sex/Gender

FEMALE

Age

18 Years to 45 Years

Healthy volunteers

Inclusion criteria

-Healthy, postpartum women as determined by medical history aged 18 - 45 years of age inclusive. -Women 1-4 days postpartum from delivery of full-term infants. Full-term will be defined as estimated gestational age of greater than or equal to 37 completed weeks of pregnancy determined by menstrual dating and concordant with ultrasound findings as per ACOG bulletin #101). -Provide written informed consent prior to initiation of any study procedures. -Available for the entire study period. -Able to understand and complete all relevant study procedures during study participation (women who ultimately have limited ability to breast feed after enrollment will not be excluded from the study).

Exclusion criteria

-Prior receipt of a tetanus or diphtheria-containing vaccine within two years of enrollment. -Prior receipt of a tetanus and diphtheria toxoid and acellular pertussis vaccine within two years of enrollment. -Known or suspected impairment of immunologic function. -Febrile illness within the last 24 hours or an oral temperature \>/= 100.4 degrees F (\>/= 38 degrees C) at the time of enrollment. -History of documented tetanus, diphtheria, or pertussis disease within the preceding 5 years. -History of allergic or adverse reaction to diphtheria, tetanus, or pertussis vaccines. -Receipt of any steroids, immunoglobulins, other blood products/transfusion within the past six months- excluding Rh immunoglobulin (Rhogam™ and Rhophylac™). -Is enrolled or plans to enroll in another clinical trial with an investigational product while participating in this study (observational studies are allowed). -Known active infection with HIV, hepatitis B, or hepatitis C. -History of alcohol or drug abuse in the last 5 years. -Any condition which, in the opinion of the investigators, may pose a health risk to the subject or interfere with the evaluation of the study objectives. -Any woman with health condition who is currently taking glucocorticoids, i.e., oral, parenteral, and high-dose inhaled steroids, and immunosuppressive or cytotoxic drugs. -Sensitive to latex, based on package insert -Progressive or unstable neurologic condition, based on package insert. -Receipt of influenza or other vaccines concomitantly administered or for 42 days following Adacel, based on package insert.

Design outcomes

Primary

Measure	Time frame	Description
Kinetics of the ELISA IgG Antibody Rise in Serum	Prior to and following Tdap, through 24 months post-vaccination	The assessment of the kinetics of the ELISA IgG antibody rise in serum was defined by the protocol as the geometric mean fold rise at each timepoint (reported separately above). No additional analysis was pre-defined or performed for this outcome measure.
ELISA GMCs of Serum IgG to PT, FHA, PRN and FIM at Week 2	2 weeks post vaccination	Blood was collected from participants at 2 weeks after vaccination for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens. A value of 5 EU/mL was imputed for results reported as below LLOQ. The geometric mean of participants' concentrations at the timepoint was calculated, along with the 95% CI.
ELISA GMCs of Serum IgG to PT, FHA, PRN and FIM at Week 6	6 weeks post vaccination	Blood was collected from participants at 6 weeks after vaccination for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens. A value of 5 EU/mL was imputed for results reported as below LLOQ. The geometric mean of participants' concentrations at the timepoint was calculated, along with the 95% CI.
ELISA GMCs of Serum IgG to PT, FHA, PRN and FIM at Month 6	6 months post vaccination	Blood was collected from participants at 6 months after vaccination for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens. A value of 5 EU/mL was imputed for results reported as below LLOQ. The geometric mean of participants' concentrations at the timepoint was calculated, along with the 95% CI.
ELISA GMCs of Serum IgG to PT, FHA, PRN and FIM at Month 12	12 months post vaccination	Blood was collected from participants at 12 months after vaccination for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens. A value of 5 EU/mL was imputed for results reported as below LLOQ. The geometric mean of participants' concentrations at the timepoint was calculated, along with the 95% CI.
ELISA GMCs of Serum IgG to PT, FHA, PRN and FIM at Month 18	18 months post vaccination	Blood was collected from participants at 18 months after vaccination for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens. A value of 5 EU/mL was imputed for results reported as below LLOQ. The geometric mean of participants' concentrations at the timepoint was calculated, along with the 95% CI.
ELISA GMCs of Serum IgG to PT, FHA, PRN and FIM at Month 24	24 months post vaccination	Blood was collected from participants at 24 months after vaccination for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens. A value of 5 EU/mL was imputed for results reported as below LLOQ. The geometric mean of participants' concentrations at the timepoint was calculated, along with the 95% CI.
Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Week 2	Prior to and 2 weeks after vaccination	Blood samples were collected from participants for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens at baseline prior to vaccination and 2 weeks after vaccination. A 4-fold rise in antibody concentration from prior to vaccination was defined as a post-vaccination IgG greater than or equal to 40 EU/mL for participants with baseline IgG concentrations less than the LLOQ (10), or 4 times the baseline IgG concentration for baseline IgG concentrations greater than the LLOQ.
Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Week 6	Prior to and 6 weeks after vaccination	Blood samples were collected from participants for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens at baseline prior to vaccination and 6 weeks after vaccination. A 4-fold rise in antibody concentration from prior to vaccination was defined as a post-vaccination IgG greater than or equal to 40 EU/mL for participants with baseline IgG concentrations less than the LLOQ (10), or 4 times the baseline IgG concentration for baseline IgG concentrations greater than the LLOQ.
Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 6	Prior to and 6 months after vaccination	Blood samples were collected from participants for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens at baseline prior to vaccination and 6 months after vaccination. A 4-fold rise in antibody concentration from prior to vaccination was defined as a post-vaccination IgG greater than or equal to 40 EU/mL for participants with baseline IgG concentrations less than the LLOQ (10), or 4 times the baseline IgG concentration for baseline IgG concentrations greater than the LLOQ.
Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 12	Prior to and 12 months after vaccination	Blood samples were collected from participants for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens at baseline prior to vaccination and 12 months after vaccination. A 4-fold rise in antibody concentration from prior to vaccination was defined as a post-vaccination IgG greater than or equal to 40 EU/mL for participants with baseline IgG concentrations less than the LLOQ (10), or 4 times the baseline IgG concentration for baseline IgG concentrations greater than the LLOQ.
Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 18	Prior to and 18 months after vaccination	Blood samples were collected from participants for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens at baseline prior to vaccination and 18 months after vaccination. A 4-fold rise in antibody concentration from prior to vaccination was defined as a post-vaccination IgG greater than or equal to 40 EU/mL for participants with baseline IgG concentrations less than the LLOQ (10), or 4 times the baseline IgG concentration for baseline IgG concentrations greater than the LLOQ.
Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 24	Prior to and 24 months after vaccination	Blood samples were collected from participants for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens at baseline prior to vaccination and 24 months after vaccination. A 4-fold rise in antibody concentration from prior to vaccination was defined as a post-vaccination IgG greater than or equal to 40 EU/mL for participants with baseline IgG concentrations less than the LLOQ (10), or 4 times the baseline IgG concentration for baseline IgG concentrations greater than the LLOQ.
Geometric Mean Fold Rise in Serum IgG by ELISA at Week 6	Prior to and 6 weeks following vaccination	Blood was collected from participants at baseline prior to vaccination and at 6 weeks after vaccination for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens. The geometric mean of participants' fold rise in antibody concentrations from baseline to post vaccination was calculated, along with the 95% CI.
Geometric Mean Fold Rise in Serum Immunoglobulin G (IgG) by ELISA at Week 2	Prior to and 2 weeks following vaccination	Blood was collected from participants at baseline prior to vaccination and at 2 weeks after vaccination for assessment of IgG by ELISA against the pertussis toxin (PT), filamentous hemaggluttinin (FHA), pertactin (PRN) and fimbrae (FIM) antigens. Antibody concentrations were reported as ELISA units per milliliter (EU/mL). The geometric mean of participants' fold rise in antibody concentrations from baseline to post vaccination was calculated, along with the 95% confidence interval (CI).
Geometric Mean Fold Rise in Serum IgG by ELISA at Month 6	Prior to and 6 months following vaccination	Blood was collected from participants at baseline prior to vaccination and at 6 months after vaccination for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens. The geometric mean of participants' fold rise in antibody concentrations from baseline to post vaccination was calculated, along with the 95% CI.
Geometric Mean Fold Rise in Serum IgG by ELISA at Month 12	Prior to and 12 months following vaccination	Blood was collected from participants at baseline prior to vaccination and at 12 months after vaccination for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens. The geometric mean of participants' fold rise in antibody concentrations from baseline to post vaccination was calculated, along with the 95% CI.
Geometric Mean Fold Rise in Serum IgG by ELISA at Month 18	Prior to and 18 months following vaccination	Blood was collected from participants at baseline prior to vaccination and at 18 months after vaccination for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens. The geometric mean of participants' fold rise in antibody concentrations from baseline to post vaccination was calculated, along with the 95% CI.
Geometric Mean Fold Rise in Serum IgG by ELISA at Month 24	Prior to and 24 months following vaccination	Blood was collected from participants at baseline prior to vaccination and at 24 months after vaccination for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens. The geometric mean of participants' fold rise in antibody concentrations from baseline to post vaccination was calculated, along with the 95% CI.
ELISA Geometric Mean Concentrations (GMC) of Serum IgG to PT, FHA, PRN and FIM at Baseline	Baseline (prior to vaccination)	Blood was collected from participants at baseline prior to vaccination for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens. Antibody concentrations were reported as ELISA units per milliliter (EU/mL). A value of 5 EU/mL was imputed for results reported as below the lower limit of quantitation (LLOQ) (\<10 EU/mL). The geometric mean of participants' concentrations at the timepoint was calculated, along with the 95% CI.

Secondary

Measure	Time frame	Description
ELISA GMC of Breast Milk IgA to PT at Week 2	2 weeks post vaccination	Breast milk was collected from participants at 2 weeks after vaccination for assessment of secretory IgA (sIgA) to PT and FHA by ELISA. Available data at the timepoint were summarized by geometric mean of the concentration as reported in EU/mL. Note that for the PT at this timepoint, all participants had a value of 5, the imputed value for below the LLOQ of the assay (\<10), and so the 95% CI is not reported, as there was no measurable variability in the data. The range is reported.
ELISA GMC of Breast Milk IgA to PT at Week 6	6 weeks post vaccination	Breast milk was collected from participants at 6 weeks after vaccination for assessment of secretory IgA (sIgA) to PT and FHA by ELISA. Available data at the timepoint were summarized by geometric mean of the concentration as reported in EU/mL. Note that for the PT at this timepoint, all participants had a value of 5, the imputed value for below the LLOQ of the assay (\<10), and so the 95% CI is not reported, as there was no measurable variability in the data. The range is reported.
ELISA GMC of Breast Milk IgA to PT at Month 6	6 months post vaccination	Breast milk was collected from participants at 6 weeks after vaccination for assessment of secretory IgA (sIgA) to PT and FHA by ELISA. Available data at the timepoint were summarized by geometric mean of the concentration as reported in EU/mL. Note that for the PT at this timepoint, all participants had a value of 5, the imputed value for below the LLOQ of the assay (\<10), and so the 95% CI is not reported, as there was no measurable variability in the data. The range is reported.
ELISA GMC of Breast Milk IgA to FHA at Baseline.	Baseline (prior to vaccination)	Breast milk (colostrum) was collected from participants at baseline prior to vaccination for assessment of secretory IgA (sIgA) to the FHA antigen by ELISA. Available data at the timepoint were summarized by geometric mean of the concentration as reported in EU/mL along with the 95% confidence interval.
ELISA GMC of Breast Milk IgA to FHA at Week 2.	2 weeks post vaccination	Breast milk was collected from participants at 2 weeks post vaccination for assessment of secretory IgA (sIgA) to the FHA antigen by ELISA. Available data at the timepoint were summarized by geometric mean of the concentration as reported in EU/mL along with the 95% confidence interval.
ELISA GMC of Breast Milk IgA to FHA at Week 6.	6 weeks post vaccination	Breast milk was collected from participants at 6 weeks post vaccination for assessment of secretory IgA (sIgA) to the FHA antigen by ELISA. Available data at the timepoint were summarized by geometric mean of the concentration as reported in EU/mL. Note that for the FHA at this timepoint, all participants had a concentration of 5, the imputed value for below the LLOQ of the assay (\<10), and so the 95% CI is not reported, as there was no measurable variability in the data. The range is reported.
ELISA GMC of Breast Milk IgA to FHA at Month 6.	6 months post vaccination	Breast milk was collected from participants at 6 months post vaccination for assessment of secretory IgA (sIgA) to the FHA antigen by ELISA. Available data at the timepoint were summarized by geometric mean of the concentration as reported in EU/mL along with the 95% confidence interval.
ELISA GMC of Breast Milk IgA to PRN and FIM by Study Day.	Baseline (prior to vaccination), Week 2, Week 6 and Month 6 post vaccination	Breast milk (colostrum) was collected from participants at baseline prior to vaccination for assessment of secretory IgA (sIgA) to the PRN and FIM antigen by ELISA. Available data at the timepoint were to be summarized by geometric mean of the concentration as reported in EU/mL along with the 95% confidence interval. The lower limit of quantitation (LLOQ) of the assay was 10 EU/mL.
Proportion of Participants With 4-fold Rise in Antibody in Breast Milk by Study Day.	Prior to vaccination, 2 weeks, 6 weeks, and 6 months after vaccination	Breast milk samples were collected from participants for evaluation of PT and FHA secretory IgA (sIgA) by ELISA. The lower limit of quantification (LLOQ) for the assay was 10 EU/mL. A 4-fold rise in concentration from prior to vaccination was defined as a post-vaccination sIgA concentration greater than or equal to 40 EU/mL for participants with baseline sIgA concentrations less than the LLOQ, or 4 times the baseline sIgA concentration for baseline sIgA concentrations greater than the LLOQ.
Geometric Mean Fold Rise in Antibody Concentrations Assessed by ELISA in Breast Milk by Study Day	Prior to vaccination, 2 weeks, 6 weeks, and 6 months after vaccination	Breast milk samples were collected from participants for evaluation of secretory IgA (sIgA) by ELISA. Geometric mean fold rise was defined as the geometric mean of participants' fold rise in post vaccination sIgA relative to the pre-vaccination sIgA.
Kinetics of the ELISA IgG Antibody Decline in Breast Milk Expressed in EU/ml.	Prior to vaccination, 2 weeks, 6 weeks, and 6 months after vaccination	Breast milk samples were collected from participants for evaluation of PT and FHA secretory IgA (sIgA) by ELISA. The protocol defined kinetics as assessment at each post-vaccination timepoint of the geometric mean fold rise, defined as the geometric mean of participants' fold rise in post vaccination sIgA relative to the pre-vaccination sIgA.
ELISA GMC of Breast Milk IgA to Pertussis Toxin (PT) at Baseline.	Baseline (prior to vaccination)	Breast milk (colostrum) was collected from participants at baseline prior to vaccination for assessment of secretory IgA (sIgA) to the PT antigen by ELISA. Available data at the timepoint were summarized by geometric mean of the concentration as reported in EU/mL along with the 95% confidence interval. The lower limit of quantitation (LLOQ) of the assay was 10. Results of \<10 were reported as half the LLOQ (5).

Countries

United States

Participant flow

Recruitment details

Postpartum participants were recruited within 1-4 days of full-term delivery in the Nashville area between 26Oct2012 and 03Sep2013.

Participants by arm

Arm	Count
Adacel® Tdap Vaccine Postpartum participants receive a single intramuscular (IM) 0.5 mL dose of Adacel® (Tetanus toxoid, reduced diphtheria toxoid and acellular pertussis vaccine adsorbed) as a single intramuscular (IM) 0.5 mL dose	55
Total	55

Withdrawals & dropouts

Period	Reason	FG000
Overall Study	Lost to Follow-up	6
Overall Study	Physician Decision	5
Overall Study	Withdrawal by Subject	8

Baseline characteristics

Characteristic	Adacel® Tdap Vaccine
Age, Categorical <=18 years	0 Participants
Age, Categorical >=65 years	0 Participants
Age, Categorical Between 18 and 65 years	55 Participants
Age, Continuous	30.1 years STANDARD_DEVIATION 4.4
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	55 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants
Race (NIH/OMB) Asian	2 Participants
Race (NIH/OMB) Black or African American	1 Participants
Race (NIH/OMB) More than one race	0 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants
Race (NIH/OMB) White	52 Participants
Region of Enrollment United States	55 participants
Sex: Female, Male Female	55 Participants
Sex: Female, Male Male	0 Participants

Adverse events

Event type	EG000 affected / at risk
deaths Total, all-cause mortality	— / —
other Total, other adverse events	0 / 55
serious Total, serious adverse events	0 / 55

Outcome results

Primary

Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 12

Blood samples were collected from participants for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens at baseline prior to vaccination and 12 months after vaccination. A 4-fold rise in antibody concentration from prior to vaccination was defined as a post-vaccination IgG greater than or equal to 40 EU/mL for participants with baseline IgG concentrations less than the LLOQ (10), or 4 times the baseline IgG concentration for baseline IgG concentrations greater than the LLOQ.

Time frame: Prior to and 12 months after vaccination

Population: All participants with blood collected and results reported at both timepoints are included in the analysis population.

Arm	Measure	Group	Value (COUNT_OF_PARTICIPANTS)
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 12	PT	5 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 12	FHA	5 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 12	PRN	28 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 12	FIM	26 Participants

Primary

Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 18

Blood samples were collected from participants for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens at baseline prior to vaccination and 18 months after vaccination. A 4-fold rise in antibody concentration from prior to vaccination was defined as a post-vaccination IgG greater than or equal to 40 EU/mL for participants with baseline IgG concentrations less than the LLOQ (10), or 4 times the baseline IgG concentration for baseline IgG concentrations greater than the LLOQ.

Time frame: Prior to and 18 months after vaccination

Population: All participants with blood collected and results reported at both timepoints are included in the analysis population.

Arm	Measure	Group	Value (COUNT_OF_PARTICIPANTS)
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 18	FHA	7 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 18	PT	3 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 18	PRN	25 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 18	FIM	26 Participants

Primary

Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 24

Blood samples were collected from participants for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens at baseline prior to vaccination and 24 months after vaccination. A 4-fold rise in antibody concentration from prior to vaccination was defined as a post-vaccination IgG greater than or equal to 40 EU/mL for participants with baseline IgG concentrations less than the LLOQ (10), or 4 times the baseline IgG concentration for baseline IgG concentrations greater than the LLOQ.

Time frame: Prior to and 24 months after vaccination

Population: All participants with blood collected and results reported at both timepoints are included in the analysis population.

Arm	Measure	Group	Value (COUNT_OF_PARTICIPANTS)
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 24	PT	1 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 24	FHA	2 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 24	PRN	19 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 24	FIM	20 Participants

Primary

Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 6

Blood samples were collected from participants for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens at baseline prior to vaccination and 6 months after vaccination. A 4-fold rise in antibody concentration from prior to vaccination was defined as a post-vaccination IgG greater than or equal to 40 EU/mL for participants with baseline IgG concentrations less than the LLOQ (10), or 4 times the baseline IgG concentration for baseline IgG concentrations greater than the LLOQ.

Time frame: Prior to and 6 months after vaccination

Population: All participants with blood collected and results reported at both timepoints are included in the analysis population.

Arm	Measure	Group	Value (COUNT_OF_PARTICIPANTS)
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 6	PT	5 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 6	FHA	18 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 6	PRN	34 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Month 6	FIM	29 Participants

Primary

Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Week 2

Blood samples were collected from participants for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens at baseline prior to vaccination and 2 weeks after vaccination. A 4-fold rise in antibody concentration from prior to vaccination was defined as a post-vaccination IgG greater than or equal to 40 EU/mL for participants with baseline IgG concentrations less than the LLOQ (10), or 4 times the baseline IgG concentration for baseline IgG concentrations greater than the LLOQ.

Time frame: Prior to and 2 weeks after vaccination

Population: All participants with blood collected and results reported at both timepoints are included in the analysis population.

Arm	Measure	Group	Value (COUNT_OF_PARTICIPANTS)
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Week 2	PT	31 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Week 2	FHA	45 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Week 2	PRN	43 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Week 2	FIM	34 Participants

Primary

Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Week 6

Blood samples were collected from participants for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens at baseline prior to vaccination and 6 weeks after vaccination. A 4-fold rise in antibody concentration from prior to vaccination was defined as a post-vaccination IgG greater than or equal to 40 EU/mL for participants with baseline IgG concentrations less than the LLOQ (10), or 4 times the baseline IgG concentration for baseline IgG concentrations greater than the LLOQ.

Time frame: Prior to and 6 weeks after vaccination

Population: All participants with blood collected and results reported at both timepoints are included in the analysis population.

Arm	Measure	Group	Value (COUNT_OF_PARTICIPANTS)
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Week 6	PT	21 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Week 6	FHA	44 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Week 6	PRN	42 Participants
Adacel® Tdap Vaccine	Count of Participants With 4-fold Rise in ELISA Antibody Concentrations at Week 6	FIM	34 Participants

Primary

ELISA Geometric Mean Concentrations (GMC) of Serum IgG to PT, FHA, PRN and FIM at Baseline

Blood was collected from participants at baseline prior to vaccination for assessment of IgG by ELISA against the PT, FHA, PRN and FIM antigens. Antibody concentrations were reported as ELISA units per milliliter (EU/mL). A value of 5 EU/mL was imputed for results reported as below the lower limit of quantitation (LLOQ) (\<10 EU/mL). The geometric mean of participants' concentrations at the timepoint was calculated, along with the 95% CI.

Time frame: Baseline (prior to vaccination)