A PHASE 2B, PLACEBO-CONTROLLED, RANDOMIZED, OBSERVER-BLINDED TRIAL TO EVALUATE THE SAFETY, TOLERABILITY, AND IMMUNOGENICITY OF A MULTIVALENT GROUP B STREPTOCOCCUS VACCINE WHEN ADMINISTERED CONCOMITANTLY WITH TETANUS, DIPHTHERIA, AND ACELLULAR PERTUSSIS VACCINE (TDAP) IN HEALTHY NONPREGNANT WOMEN 18 THROUGH 49 YEARS OF AGE
Phase: PHASE2
Conditions: Group B Streptococcus Infections
Sponsor: Pfizer

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
Page 1 
 
 
 
 
 
 
 
A PHASE 2B, PLACEBO-CONTROLLED, RANDOMIZED, OBSERVER-BLINDED 
TRIAL TO EVALUATE THE SAFETY, TOLERABILITY, AND 
IMMUNOGENICITY OF A MULTIVALENT GROUP B STREPTOCOCCUS 
VACCINE WHEN ADMINISTERED CONCOMITANTLY WITH TETANUS, 
DIPHTHERIA, AND ACELLULAR PERTUSSIS VACCINE (TDAP) IN HEALTHY 
NONPREGNANT WOMEN 18 THROUGH 49 YEARS OF AGE 
 
Study Intervention Number: 
PF-06760805 
Study Intervention Name: 
Group B Streptococcus 6-Valent 
Polysaccharide Conjugate Vaccine (GBS6) 
US IND Number: 
CCI  
EudraCT Number: 
Not Applicable (N/A) 
Protocol Number: 
C1091005 
Phase: 
2b 
Brief Title: Group B Streptococcus Vaccine and Concomitant Administration of Tdap in 
Nonpregnant Women 
 
 
This document and accompanying materials contain confidential information belonging to Pfizer. Except as 
otherwise agreed to in writing, by accepting or reviewing these documents, you agree to hold this 
information in confidence and not copy or disclose it to others (except where required by applicable law) or 
use it for unauthorized purposes. In the event of any actual or suspected breach of this obligation, Pfizer 
must be promptly notified. 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
Page 2 
 
 
Document History 
 
Document 
Version Date 
Amendment 3 
04 October 2022 
Amendment 2 
11 April 2022 
Amendment 1 
22 January 2021 
Original protocol 
08 December 2020 
 
This amendment incorporates all revisions to date, including amendments made at the 
request of country health authorities and IRBs/ECs and any protocol administrative change 
letter(s). 
Protocol Amendment Summary of Changes Table 
Amendment 3 (04 October 2022) 
Overall Rationale for the Amendment: The addition of Visit 3 will be a 6-month safety 
follow-up telephone call. Visit 3 is added to address CBER’s request for a 6-month safety 
follow-up. 
 
Section # and Name 
Description of Change 
Brief Rationale 
Section 1.1: Synopsis 
Section 1.3: Schedule of 
Activities 
Section 3: Objectives, Estimands, 
and Endpoints 
Section 4.1: Overall Design 
Section 5.2: Exclusion Criteria 
Section 6.5.3: Recording 
Nonstudy Vaccinations and 
Concomitant Medications 
Section 8.3.1: Time Period and 
Frequency for Collecting AE and 
SAE Information 
Section 8.3.5.1: Exposure During 
Pregnancy 
Section 8.11.3: Visit 3 – 6-Month 
Telephone Call Follow-up Visit 
(160-200 Days After Visit 1) 
Section 8.11.4: Unscheduled 
Visits 
• The addition of 
Visit 3 will be a 
6-month safety 
follow-up telephone 
call. 
• A 6-month safety 
follow-up telephone 
call has been added to 
address CBER 
feedback. 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
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Section # and Name 
Description of Change 
Brief Rationale 
Section 9.1.2: Estimands 
Section 9.5: Interim Analyses 
Section 10.6: Appendix 6: 
Protocol Amendment History 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
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TABLE OF CONTENTS 
LIST OF TABLES ..................................................................................................................... 8 
1. PROTOCOL SUMMARY ..................................................................................................... 9 
1.1. Synopsis ..................................................................................................................... 9 
1.2. Schema..................................................................................................................... 13 
1.3. Schedule of Activities .............................................................................................. 14 
2. INTRODUCTION ................................................................................................................ 16 
2.1. Study Rationale ........................................................................................................ 16 
2.2. Background .............................................................................................................. 16 
2.2.1. Disease Overview ........................................................................................ 16 
2.2.2. Maternal Immunization as an Approach to Prevent Disease in Infants 
and Pregnant Women ....................................................................................... 17 
2.3. Benefit/Risk Assessment ......................................................................................... 18 
2.3.1. Risk Assessment ......................................................................................... 19 
2.3.2. Benefit Assessment ..................................................................................... 21 
2.3.3. Overall Benefit/Risk Conclusion ................................................................ 21 
3. OBJECTIVES, ESTIMANDS, AND ENDPOINTS ............................................................ 21 
4. STUDY DESIGN ................................................................................................................. 24 
4.1. Overall Design ......................................................................................................... 24 
4.2. Scientific Rationale for Study Design ..................................................................... 24 
4.3. Justification for Dose ............................................................................................... 24 
4.4. End of Study Definition ........................................................................................... 25 
5. STUDY POPULATION ...................................................................................................... 25 
5.1. Inclusion Criteria ..................................................................................................... 25 
5.2. Exclusion Criteria .................................................................................................... 26 
5.3. Lifestyle Considerations .......................................................................................... 27 
5.3.1. Contraception .............................................................................................. 27 
5.4. Screen Failures ........................................................................................................ 27 
5.5. Criteria for Temporarily Delaying 
Enrollment/Randomization/Administration of Study Intervention ........................... 28 
5.5.1. Temporary Delay Criteria ........................................................................... 28 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
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5.5.1.1. Criteria  for  Temporarily  Delaying  Vaccine 
Administration .................................................................................. 28 
5.5.1.2. Criteria for Temporarily Delaying Blood Draw ........................ 28 
6. STUDY INTERVENTION(S) AND CONCOMITANT THERAPY ................................. 28 
6.1. Study Intervention(s) Administered ........................................................................ 28 
6.1.1. GBS6 .......................................................................................................... 29 
6.1.2. Tdap ........................................................................................................... 29 
6.1.3. Placebo ....................................................................................................... 29 
6.1.4. Administration ............................................................................................ 29 
6.2. Preparation/Handling/Storage/Accountability ......................................................... 30 
6.2.1. Preparation and Dispensing ........................................................................ 31 
6.3. Measures to Minimize Bias: Randomization and Blinding .................................... 32 
6.3.1. Allocation to Study Intervention ................................................................ 32 
6.3.2. Blinding of the Site Personnel .................................................................... 32 
6.3.3. Blinding of the Sponsor ............................................................................. 32 
6.3.4. Breaking the Blind ..................................................................................... 33 
6.4. Study Intervention Compliance .............................................................................. 33 
6.5. Concomitant Therapy ............................................................................................. 33 
6.5.1. Prohibited Nonstudy Vaccines and Medications During the Study ........... 33 
6.5.2. Permitted Nonstudy Vaccines and Medications During the Study ............ 33 
6.5.3. Recording Nonstudy Vaccinations and Concomitant Medications ............ 34 
6.6. Dose Modification .................................................................................................. 34 
6.7. Intervention After the End of the Study ................................................................. 34 
7. DISCONTINUATION OF STUDY INTERVENTION AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL ........................................................................... 34 
7.1. Discontinuation of Study Intervention .................................................................... 34 
7.2. Participant Discontinuation/Withdrawal From the Study ...................................... 34 
7.2.1. Withdrawal of Consent .............................................................................. 35 
7.3. Lost to Follow-up ................................................................................................... 36 
8. STUDY ASSESSMENTS AND PROCEDURES .............................................................. 36 
8.1. Efficacy and/or Immunogenicity Assessments ....................................................... 37 
8.1.1. GBS Vaccine Antibody Testing ................................................................. 37 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
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8.1.2. Tdap Antibody Testing ............................................................................... 37 
8.1.3. Biological Samples ..................................................................................... 38 
8.2. Safety Assessments .................................................................................................. 38 
8.2.1. Participant E-Diary ..................................................................................... 38 
8.2.2. Grading Scale for Prompted Events ............................................................ 39 
8.2.2.1. Local Reactions ......................................................................... 39 
8.2.2.2. Systemic Events ......................................................................... 40 
8.2.2.3. Fever .......................................................................................... 41 
8.2.3. Use of Antipyretic/Pain Medication ............................................................ 42 
8.2.4. Clinical Safety Laboratory Assessments ..................................................... 42 
8.2.5. Pregnancy Testing ....................................................................................... 42 
8.3. Adverse Events and Serious Adverse Events .......................................................... 42 
8.3.1. Time Period and Frequency for Collecting AE and SAE Information ....... 43 
8.3.1.1. Reporting SAEs to Pfizer Safety ............................................... 43 
8.3.1.2. Recording Nonserious AEs and SAEs on the CRF ................... 43 
8.3.2. Method of Detecting AEs and SAEs ........................................................... 44 
8.3.3. Follow-up of AEs and SAEs ....................................................................... 44 
8.3.4. Regulatory Reporting Requirements for SAEs ........................................... 44 
8.3.5. Environmental Exposure, Exposure During Pregnancy or 
Breastfeeding, and Occupational Exposure ..................................................... 45 
8.3.5.1. Exposure During Pregnancy ...................................................... 45 
8.3.5.2. Exposure During Breastfeeding ................................................. 46 
8.3.5.3. Occupational Exposure .............................................................. 47 
8.3.6. Cardiovascular and Death Events ................................................................ 47 
8.3.7. Disease-Related Events and/or Disease-Related Outcomes Not 
Qualifying as AEs or SAEs .............................................................................. 47 
8.3.8. Adverse Events of Special Interest ............................................................. 47 
8.3.8.1. Lack of Efficacy ........................................................................ 47 
8.3.9. Medical Device Deficiencies ...................................................................... 47 
8.3.10. Medication Errors ...................................................................................... 48 
8.4. Treatment of Overdose ............................................................................................ 49 
8.5. Pharmacokinetics ..................................................................................................... 49 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
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8.6. Pharmacodynamics ................................................................................................. 49 
8.7. Genetics .................................................................................................................. 49 
8.8. Biomarkers .............................................................................................................. 49 
8.9. Immunogenicity Assessments ................................................................................ 49 
8.10. Health Economics ................................................................................................. 49 
8.11. Study Procedures .................................................................................................. 50 
8.11.1. Visit 1 – Vaccination (Day 1) .................................................................. 50 
8.11.2. Visit 2 – 1-Month Follow-up Visit (28-38 Days After Visit 1) ............... 52 
8.11.3. Visit 3 – 6-Month Telephone Call Follow-up Visit (160-200 Days 
After Visit 1) ................................................................................................... 52 
8.11.4. Unscheduled Visits .................................................................................. 52 
9. STATISTICAL CONSIDERATIONS ................................................................................ 54 
9.1. Estimands and Statistical Hypotheses .................................................................... 54 
9.1.1. Statistical Hypotheses ................................................................................ 54 
9.1.2. Estimands ................................................................................................... 54 
9.2. Sample Size Determination .................................................................................... 56 
9.3. Analysis Sets ........................................................................................................... 57 
9.4. Statistical Analyses ................................................................................................. 57 
9.4.1. Safety Analyses .......................................................................................... 57 
9.4.2. Immunogenicity Analyses .......................................................................... 58 
9.5. Interim Analyses ..................................................................................................... 61 
9.6. Data Monitoring Committee or Other Independent Oversight Committee ............ 61 
10. SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS.......................................................................................................... 62 
10.1. Appendix 1: Regulatory, Ethical, and Study Oversight Considerations ............... 62 
10.1.1. Regulatory and Ethical Considerations .................................................... 62 
10.1.1.1. Reporting of Safety Issues and Serious Breaches of the 
Protocol or ICH GCP ........................................................................ 62 
10.1.2. Financial Disclosure ................................................................................. 63 
10.1.3. Informed Consent Process ....................................................................... 63 
10.1.4. Data Protection ......................................................................................... 64 
10.1.5. Dissemination of Clinical Study Data ...................................................... 64 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
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10.1.6. Data Quality Assurance ............................................................................ 65 
10.1.7. Source Documents ................................................................................... 66 
10.1.8. Study and Site Start and Closure .............................................................. 67 
10.1.9. Publication Policy .................................................................................... 68 
10.1.10. Sponsor’s Qualified Medical Personnel ................................................. 69 
10.2. Appendix 2: Clinical Laboratory Tests ................................................................ 69 
10.3. Appendix 3: Adverse Events: Definitions and Procedures for Recording, 
Evaluating, Follow-up, and Reporting ...................................................................... 70 
10.3.1. Definition of AE ....................................................................................... 70 
10.3.2. Definition of an SAE ................................................................................ 71 
10.3.3. Definition of Medically Attended Adverse Event ................................... 72 
10.3.4. Definition of Immediate Adverse Event .................................................. 73 
10.3.5. Recording/Reporting and Follow-up of AEs and/or SAEs ...................... 73 
10.3.6. Reporting of SAEs ................................................................................... 76 
10.4. Appendix 4: Contraceptive Guidance ................................................................... 78 
10.4.1. Female Participant Reproductive Inclusion Criteria ................................ 78 
10.4.2. Woman of Childbearing Potential ............................................................ 78 
10.4.3. Contraception Methods ............................................................................ 79 
10.5. Appendix 5: Liver Safety: Suggested Actions and Follow-up Assessments ........ 81 
10.6. Appendix 6: Protocol Amendment History .......................................................... 83 
10.7. Appendix 7: Abbreviations ................................................................................... 87 
11. REFERENCES .................................................................................................................. 90 
 
LIST OF TABLES 
Table 1. 
Local Reaction Grading Scale ................................................................. 40 
Table 2. 
Systemic Event Grading Scale ................................................................. 41 
Table 3. 
Ranges for Fever ...................................................................................... 42 
Table 4. 
Probability of Observing at Least 1 Event by Assumed True Event 
Rates .......................................................................................................... 57 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
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1. PROTOCOL SUMMARY 
1.1. Synopsis 
Rationale 
Pfizer is developing a group B streptococcus 6-valent polysaccharide conjugate vaccine 
(GBS6) for the prevention of group B streptococcal invasive disease due to the 6 serotypes 
that cause the majority of disease in infants (serotypes Ia, Ib, II, III, IV, and V) by active 
immunization of pregnant women. Pregnant women have been vaccinated globally to 
prevent neonatal tetanus and pertussis in young infants, and to protect women and their 
infants against influenza. 
Tetanus- and pertussis-containing vaccines are recommended in many countries during 
pregnancy. In the US, tetanus, diphtheria, and acellular pertussis vaccine (Tdap) is 
recommended for administration between 27 and 36 weeks of gestation. As GBS6 is being 
evaluated for administration within the same gestational timeframe, information on the safety 
and potential immune interference of concomitantly administered Tdap and GBS6 is 
important to understand prior to GBS6 licensure. 
Study C1091005 is a descriptive study that will evaluate the concomitant administration of 
GBS6 and Tdap among nonpregnant women to rule out significant interference. The study is 
expected to provide useful data prior to the Phase 3 definitive coadministration assessment 
program in pregnant women. 
Objectives, Estimands, and Endpoints 
 
Objectives 
Estimands 
Endpoints 
Primary (Safety): 
Primary (Safety): 
Primary (Safety): 
• To describe the 
safety and 
tolerability of 
GBS6 when 
administered 
concomitantly 
with Tdap 
(GBS6+Tdap) 
and when GBS6 
is administered 
alone 
(GBS6+placebo). 
In participants receiving at least 1 dose of the 
investigational products: 
• The proportion of participants reporting 
prompted local reactions within 7 days 
following investigational product 
administration. 
• The proportion of participants reporting 
prompted systemic events within 7 days 
following investigational product 
administration. 
• The proportion of participants reporting 
adverse events (AEs) through 1 month 
following investigational product 
administration. 
• The proportion of participants reporting 
medically attended adverse events 
(MAEs) and serious adverse events 
(SAEs) through 6 months following 
investigational product administration. 
• Prompted local reactions (redness, swelling, 
and pain at the injection site). 
• Prompted systemic events (fever, 
nausea/vomiting, diarrhea, headache, fatigue, 
muscle pain, and joint pain). 
• AEs. 
• MAEs and SAEs. 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
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Objectives 
Estimands 
Endpoints 
Primary 
(Immunogenicity): 
Primary (Immunogenicity): 
Primary (Immunogenicity): 
• To describe the 
immune 
responses 
induced by Tdap 
when 
administered 
concomitantly 
with GBS6 
(GBS6+Tdap) 
compared to the 
immune 
responses 
induced by Tdap 
(placebo+Tdap) 
alone. 
In participants receiving all doses of the 
investigational products and in compliance 
with the key protocol criteria (evaluable 
participants): 
• The difference in proportions of 
participants with anti–tetanus toxoid 
antibody concentrations ≥0.1 IU/mL 
measured 1 month after vaccination 
between the GBS6+Tdap group and the 
placebo+Tdap group. 
• The difference in proportions of 
participants with anti–diphtheria toxoid 
antibody concentrations ≥0.1 IU/mL 
measured 1 month after vaccination 
between the GBS6+Tdap group and the 
placebo+Tdap group. 
• Geometric mean ratio (GMR), estimated 
by the GMR of anti–pertussis toxin 
antibodies from the GBS6+Tdap group to 
the placebo+Tdap group measured 
1 month after vaccination. 
• GMR, estimated by the GMR of 
anti–filamentous hemagglutinin 
(anti-FHA) antibodies from the 
GBS6+Tdap group to the placebo+Tdap 
group measured 1 month after 
vaccination. 
• GMR, estimated by the GMR of 
antipertactin (anti-PRN) antibodies from 
the GBS6+Tdap group to the 
placebo+Tdap group measured 1 month 
after vaccination. 
• Anti–tetanus toxoid and anti–diphtheria 
toxoid antibodies and anti–pertussis 
component (pertussis toxin, FHA, and PRN) 
antibodies. 
• To describe the 
immune 
responses 
induced by 
GBS6 when 
administered 
concomitantly 
with Tdap 
(GBS6+Tdap) 
compared to the 
immune 
responses 
induced by 
GBS6 
(GBS6+placebo) 
alone. 
• GBS capsular polysaccharide (CPS) 
serotype-specific IgG GMR, estimated by 
the GMR of GBS CPS serotype-specific 
IgG antibodies from the GBS6+Tdap 
group to the GBS6+placebo group 
measured 1 month after vaccination. 
• GBS CPS serotype-specific IgG antibody 
concentrations. 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
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Objectives 
Estimands 
Endpoints 
Secondary: 
Secondary: 
Secondary: 
• N/A 
• N/A 
• N/A 
Exploratory 
(Immunogenicity): 
Exploratory (Immunogenicity): 
Exploratory (Immunogenicity): 
• To further 
describe the 
immune 
responses 
elicited by Tdap 
when 
administered 
concomitantly 
with GBS6 
(GBS6+Tdap) 
compared to 
Tdap 
(placebo+Tdap) 
alone. 
In participants receiving all doses of the 
investigational products and in compliance 
with the key protocol criteria (evaluable 
participants): 
• Proportions of participants with 
anti–tetanus toxoid and 
anti–diphtheria toxoid antibody 
concentrations ≥0.1 IU/mL measured 
before vaccination and 1 month after 
vaccination for both the GBS6+Tdap 
group and the placebo+Tdap group. 
• Proportions of participants with 
anti–tetanus toxoid and 
anti–diphtheria toxoid antibody 
concentrations ≥1.0 IU/mL measured 
before vaccination and 1 month after 
vaccination for both the GBS6+Tdap 
group and the placebo+Tdap group. 
• The differences in proportions of 
participants with anti–tetanus toxoid and 
anti–diphtheria toxoid antibody 
concentrations ≥1.0 IU/mL measured at 
1 month after vaccination between the 
GBS6+Tdap group and the 
placebo+Tdap group. 
• GMCs of anti–tetanus toxoid, 
anti–diphtheria toxoid, and 
anti–pertussis component (pertussis 
toxin, FHA, PRN, and FIM) antibodies 
measured before vaccination and 
1 month after vaccination for both the 
GBS6+Tdap group and the 
placebo+Tdap group. 
• Geometric mean fold rise (GMFRs) of 
anti–tetanus toxoid, anti-diphtheria 
toxoid, and anti–pertussis component 
(pertussis toxin, FHA, PRN, and FIM) 
antibodies measured from before 
vaccination to 1 month after vaccination 
for both the GBS6+Tdap group and the 
placebo+Tdap group. 
• Anti–tetanus toxoid, anti–diphtheria toxoid, 
and anti–pertussis component (pertussis toxin, 
FHA, PRN, and FIM) antibody 
concentrations. 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
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Objectives 
Estimands 
Endpoints 
• To further 
describe the 
immune 
responses 
elicited by GBS6 
when 
administered 
concomitantly 
with Tdap 
(GBS6+Tdap) 
compared to 
GBS6 
(GBS6+placebo) 
alone. 
• GBS CPS serotype-specific IgG GMCs 
measured before and 1 month after 
vaccination for both the GBS6+Tdap 
group and the GBS6+placebo group. 
• GBS CPS serotype-specific IgG GMFRs 
measured from before vaccination to 
1 month after vaccination for both the 
GBS6+Tdap group and the 
GBS6+placebo group. 
• GBS CPS serotype-specific IgG antibody 
concentrations. 
 
Overall Design 
This is a Phase 2, multicenter, placebo-controlled, randomized, observer-blinded study in 
which approximately 300 healthy nonpregnant women, 18 through 49 years of age, will be 
randomized to evaluate concomitant administration of GBS6 and Tdap. Participants will be 
randomized in a 1:1:1 ratio to receive 20 µg GBS6 and concomitant Tdap (GBS6+Tdap), 
20 µg GBS6 and placebo (GBS6+placebo), or Tdap and placebo (placebo+Tdap). 
Participants will have blood drawn prior to vaccination (Visit 1) and at 1 month after 
vaccination (Visit 2). Electronic diaries (e-diaries) will be used to collect prompted local 
reaction and systemic event data for 7 days after vaccination (Days 1 through 7, where Day 1 
is the day of vaccination). AEs will be collected through Visit 2. MAEs and SAEs will be 
collected through Visit 3. 
An external data monitoring committee (E-DMC) will be utilized. 
Number of Participants 
Approximately 300 participants will be randomly assigned to the investigational products to 
achieve a target of 270 evaluable participants, assuming 10% nonevaluability. 
Intervention Groups and Duration 
Participants will be enrolled and randomized in a 1:1:1 ratio to receive 1 of the 
following 3 groups: GBS6+Tdap, GBS6+placebo, or placebo+Tdap, to achieve a target 
of 270 evaluable participants, assuming 10% nonevaluability. Details of sample size 
determination can be found in Section 9.2. 
Participants will take part in the study from enrollment to approximately 6 months after 
vaccination. 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
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Data Monitoring Committee 
This study will use an established E-DMC. The E-DMC is independent of the study team 
and includes only external members. The E-DMC charter describes the role of the E-DMC 
in more detail. 
The E-DMC will be responsible for ongoing monitoring of the safety of participants in the 
study according to the charter. The recommendations made by the E-DMC to alter the 
conduct of the study will be forwarded to the appropriate Pfizer personnel for final decision. 
Pfizer will forward such decisions, which may include summaries of aggregate analyses of 
safety data, to regulatory authorities, as appropriate. 
Statistical Methods 
The statistical data analysis of the study results will be descriptive in nature. An estimation 
approach will be used to assess the safety and immunogenicity objectives in the study. 
Summary statistics will be provided for all binary and continuous endpoints related to study 
primary and exploratory objectives. 
The statistical analysis plan (SAP) will be developed and finalized before database lock and 
will describe the participant populations to be included in the analyses and the procedures for 
accounting for missing, unused, and spurious data. A summary of the planned statistical 
analyses of the primary and secondary endpoints can be found in Section 9. 
1.2. Schema 
Not applicable. 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
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1.3. Schedule of Activities 
The SoA table provides an overview of the protocol visits and procedures. Refer to the STUDY ASSESSMENTS AND 
PROCEDURES section of the protocol for detailed information on each procedure and assessment required for compliance with the 
protocol. 
The investigator may schedule visits (unplanned visits) in addition to those listed in the SoA table, in order to conduct evaluations or 
assessments required to protect the well-being of the participant. 
 
Visit Number 
1 
2 
3 
Visit Description 
Vaccination 
1-Month Follow-up Visit 
6-Month Follow-up Call 
Visit Window (Days)a 
Day 1 
28-38 Days After Visit 1 
160-200 Days After Visit 1 
Type of Visit 
Clinic 
Clinic 
Phone Call 
Obtain informed consent 
X 
Assign a participant number using the IRT system 
X 
Record demography, medical history, physical examination, vital 
signsb 
X 
Perform urine pregnancy test 
X 
Record nonstudy vaccine information 
X 
X 
X 
Record medication information 
X 
Xc 
Xc 
Review inclusion and exclusion criteria 
X 
Measure prevaccination oral temperature 
X 
Contraception checkd 
X 
X 
Review temporary delay criteria 
X 
Review continued eligibility 
X 
X 
Assign randomization and container number 
X 
Obtain blood draw for immunogenicity assessmente 
X 
(~50 mL) 
X 
(~50 mL) 
Administer investigational products 
X 
Postvaccination observation (at least 30 minutes) and assessment of 
immediate AEs 
X 
Issue/activate e-diary devicef 
X 
Issue thermometer and measuring device 
X 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
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Visit Number 
1 
2 
3 
Visit Description 
Vaccination 
1-Month Follow-up Visit 
6-Month Follow-up Call 
Visit Window (Days)a 
Day 1 
28-38 Days After Visit 1 
160-200 Days After Visit 1 
Type of Visit 
Clinic 
Clinic 
Phone Call 
Provide the participant with a contact card 
X 
Review and/or collect e-diaryg 
X 
Record AEs 
X 
X 
Record MAEs and SAEs 
X 
X 
X 
Abbreviations: AE = adverse event; IRT = interactive response technology; GBS = group B streptococcus; MAE = medically attended event; SAE = serious 
adverse event. 
a. 
Day relative to start of study vaccination (Day 1). 
b. Vital signs include weight, height, sitting blood pressure and pulse rate, respiratory rate, and temperature (oral). 
c. 
Only concomitant medications taken to treat an AE, MAE, or SAE will be recorded in the case report form, as appropriate. 
d. The contraception check is an opportunity to confirm that contraception is used consistently and correctly through the required time period per protocol 
(28 days after vaccination). 
e. 
All blood volumes are approximate and at Visit 1 will be taken prior to vaccination. 
f. 
Participants will record prompted reactogenicity events in an e-diary each evening for 7 days following vaccination (where Day 1 is the day of vaccination). 
Remind participants that study staff may contact them to obtain additional information on Grade 3 events entered into the e-diary. Ask participants to 
contact the investigator or site staff immediately if they are prompted by the e-diary from Day 1 through Day 7 following vaccination to determine if an 
unscheduled visit is required to assess a Grade 4 event. 
g. Designated site staff will review e-diary data online following vaccination to evaluate participant compliance and as part of the ongoing safety review. 

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2. INTRODUCTION 
GBS6 is being developed for: 
• Active immunization to prevent disease caused by GBS serotypes (Ia, Ib, II, III, IV, and 
V) contained in the vaccine. 
2.1. Study Rationale 
GBS6 is being developed to address the global unmet medical need for prevention of infant 
GBS disease. It is based on the well-established platform of vaccines composed of CPSs 
conjugated to the CRM197 protein that target the polysaccharide capsules of encapsulated 
bacteria. Maternal immunization with an efficacious GBS vaccine would likely offer 
benefits beyond existing approaches to prevent infant GBS disease. The vaccine may also 
protect against adverse fetal outcomes by reducing GBS colonization in pregnant women. 
Pregnant women may also benefit directly from a GBS vaccine by the prevention of 
peripartum GBS disease. Other populations, such as adults of advanced age or with 
particular GBS risk factors, may be considered for GBS6 vaccine evaluation in the future. 
Pregnant women are vaccinated globally to prevent neonatal tetanus and pertussis in young 
infants, and to protect women and their infants against influenza. 
Tetanus- and pertussis-containing vaccines are recommended in many countries during 
pregnancy. In the US, tetanus, diphtheria, and acellular pertussis vaccine (Tdap) is 
recommended for administration between 27 and 36 weeks’ gestation of each pregnancy. As 
GBS6 is being evaluated for administration within the same timeframe, information on the 
safety and potential immune interference of Tdap and GBS6 administered concomitantly are 
important to understand prior to evaluation of GBS6 in late-stage clinical trials and before 
GBS6 licensure. 
Study C1091005 is a descriptive study that will evaluate the concomitant administration of 
GBS6 and Tdap among nonpregnant women to rule out significant interference. The study is 
expected to provide data prior to the Phase 3 definitive coadministration assessment program 
in pregnant women. 
2.2. Background 
2.2.1. Disease Overview 
Streptococcus agalactiae, also known as GBS, is an encapsulated, gram-positive coccus that 
is associated with lower intestinal and rectovaginal colonization. There are 10 serotypes of 
GBS (Ia, Ib, II, III, IV, V, VI, VII, VIII, and IX) differentiated by the composition of their 
polysaccharide capsule. Although all GBS serotypes have been found to cause disease, 6 
serotypes (Ia, Ib, II, III, IV, and V) have been found to cause >95% of disease globally, with 
variability in their global prevalence and virulence.1,2 GBS disease most frequently occurs 
in the very young—newborns and infants younger than 3 months of age—and the elderly, 
especially older adults with comorbid conditions.3,4,5,6,7 However, GBS disease has been 
reported in individuals of all ages, and pregnant women may be particularly susceptible.8 

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Among infants, GBS may cause serious disease, including sepsis, meningitis, and 
pneumonia; less common manifestations include skin and soft tissue, bone, and joint 
infections.9 In pregnant women, GBS may be associated with ascending infections ranging 
from relatively benign urinary tract infections to chorioamnionitis (which may result in 
stillbirth or preterm delivery) and puerperal sepsis (which may be fatal).10 Bacteremia 
without a focus, cellulitis, bone and joint infections, and urinary tract infections are common 
disease manifestations of GBS infection in older nonpregnant adults.6,11,12 
2.2.2. Maternal Immunization as an Approach to Prevent Disease in Infants and 
Pregnant Women 
The goal of maternal immunization is to generate protective antibodies that may be 
placentally transferred in utero to provide the newborn and young infant with IgG antibody 
concentrations at birth sufficient to protect them against infections during the period of 
increased vulnerability until they are able to adequately respond to their own active 
immunizations or infectious challenges. Examples of this concept include vaccination with 
tetanus, pertussis, or influenza vaccines to provide maternally transferred antibody protection 
against the cognate pathogen. Pfizer is following this paradigm to develop vaccines for 
respiratory syncytial virus (RSV) and GBS infections.13 
Vaccination of pregnant women is used globally in the prevention of neonatal tetanus and 
pertussis in young infants, and to protect women and their infants against influenza.14,15,16,17,18 
There is increasing experience with the safety, effectiveness, and acceptance of influenza 
vaccine and tetanus toxoid– and pertussis-containing vaccines for use in pregnant women in 
various regions globally to prevent disease in newborns and infants.17,19,20 Maternal 
immunization against influenza is recommended by the US Advisory Committee on 
Immunization Practices (ACIP).21 In addition, several countries recommend maternal Tdap 
vaccination during every pregnancy, including closely spaced pregnancies. To date, these 
vaccines have demonstrated an acceptable safety profile with single and repeat dosing.22,23,24 
Current preventive measures against invasive GBS disease in infants vary by region and 
include universal screening of pregnant women in the third trimester of pregnancy and 
administration of intrapartum antibiotic prophylaxis (IAP) to prevent disease in the infant, a 
risk-based approach to IAP, or no prevention intervention.7,9,25 Each of these approaches has 
limitations, and while implementation of IAP policies has reduced incidence of early-onset 
disease (EOD), there has not been a measurable impact on late-onset disease (LOD; beyond 
the first week of life) and a significant EOD burden remains. Published data from natural 
history studies have demonstrated a general correlation between maternal GBS antibody 
levels and a reduced risk of GBS disease in newborns, with an attempt made to derive an 
immunological threshold of protection.26,27,28,29,30 These studies established clearly that 
antibodies to GBS capsular polysaccharides in the mother correlated with protection against 
GBS disease in the infant. Immunization of pregnant women with a GBS vaccine, therefore, 
is a reasonable alternative approach to prevent invasive GBS disease in young infants and 
possibly GBS disease in pregnant or postpartum women.31 A licensed GBS vaccine 
approved for administration in pregnancy would likely be given in the second trimester 
and/or during the third trimester. 

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There is currently no licensed vaccine for the prevention of GBS disease; however, Pfizer is 
developing a multivalent vaccine for the prevention of invasive GBS disease in infants. 
GBS6 was evaluated in a Phase 1/2 first-in-human (FIH) study in healthy nonpregnant 
women and men 18 through 49 years of age in the US. GBS6 was safe and well-tolerated 
and elicited robust immune responses that persisted through 6 months after vaccination at all 
dose levels and formulations. No meaningful difference in the GBS CPS IgG immune 
responses were observed for any serotype between GBS6 doses or formulations. No safety 
risks were identified beyond reactogenicity through 6 months. The safety findings from this 
FIH study are similar to those of other investigational GBS vaccines and of other licensed 
vaccines recommended for use in pregnancy.32,33,34,35 
The purpose of this Phase 2b descriptive study is to evaluate the concomitant administration 
of GBS6 and Tdap. The study is expected to provide data prior to the Phase 3 definitive 
coadministration assessment program in pregnant women, which will inform future studies 
with pregnant women in which Tdap may be used. 
2.3. Benefit/Risk Assessment 
Pfizer is developing GBS6 to address a global unmet medical need for the prevention of GBS 
disease due to 6 serotypes in young infants by active immunization of pregnant women. 
GBS6 is composed of polysaccharides of the 6 most prevalent serotypes causing >95% of 
GBS disease in infants and adults,1,4 individually conjugated to the CRM197 carrier protein. 
An efficacious vaccine would offer a favorable adjunct option to currently existing 
approaches for GBS disease prevention by providing greater feasibility of implementation in 
low- and middle-income countries (LMICs), and the potential to provide protection against 
disease, including both EOD and LOD, in infants. In addition, there is a long history of 
success in protecting pediatric and adult populations against diseases caused by encapsulated 
bacteria using vaccines that target CPSs and generate functional antibodies that eliminate 
bacteria by opsonophagocytosis. 
A completed Phase 1/2 study of GBS6 in healthy adults demonstrated that GBS6 was safe 
and well-tolerated in healthy nonpregnant women and healthy men and elicited robust 
immune responses that persisted through 6 months after vaccination at all dose levels and 
formulations evaluated. The study's safety findings were similar to those of other 
investigational GBS and licensed vaccines recommended for use in pregnancy. The data 
provide support for continuing evaluation of GBS6 in later-phase trials and in pregnant 
women. 
More detailed information about the known and expected benefits and risks and reasonably 
expected AEs of GBS6 may be found in the GBS6 investigator’s brochure (IB), which is the 
SRSD for this study. 
The SRSD for Tdap will be the product information for the US, where this vaccine will be 
procured. 

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2.3.1. Risk Assessment 
 
Potential Risk of Clinical Significance 
Summary of Data/Rationale for Risk 
Mitigation Strategy 
Study Intervention(s) – GBS6, Tdap, and Placebo 
Potential risks associated with GBS6 in the age 
group for this study include the following: 
• 
Injection site redness 
• 
Injection site swelling 
• 
Injection site pain or tenderness 
• 
Fever 
As with any vaccine, a rare but possible event 
associated with GBS6 is: 
• 
Hypersensitivity reaction, including 
swelling of the face or lips (face edema), 
wheezing (bronchospasm), or difficulty in 
breathing (dyspnea) 
The potential risks are based on the FIH 
C1091001 study results and those described in 
the IB. 
Eligibility criteria have been selected to ensure 
that only appropriate healthy participants are 
included in the study (see Section 5). 
Individuals with significant reactions after 
vaccination or AEs considered by the investigator 
to present increased risk to the participant or who 
develop exclusionary conditions during the 
conduct of the study will be excluded from 
interventions but may be followed for safety. 
Potential risks associated with Tdap in the age group 
for this study include the following: 
• 
Injection site pain 
• 
Injection site swelling 
• 
Injection site redness 
• 
Headache 
• 
Body ache or muscle weakness 
The risks are based on the known safety profile 
of a commonly used Tdap in this age group, 
presented in the Adacel USPI. 
Eligibility criteria have been selected to ensure 
that only appropriate healthy participants are 
included in the study (see Section 5). 
Individuals with significant reactions after 
vaccination or AEs considered by the investigator 
to present increased risk to the participant or who 
develop exclusionary conditions during the 
conduct of the study will be excluded from 
interventions but may be followed for safety. 

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Potential Risk of Clinical Significance 
Summary of Data/Rationale for Risk 
Mitigation Strategy 
Study Intervention(s) – GBS6, Tdap, and Placebo 
Potential risks associated with placebo in the age 
group for this study include the following: 
• 
Injection site pain 
• 
Injection site swelling 
• 
Injection site redness 
The risks are based on commonly observed 
events in vaccine studies using a placebo. 
Eligibility criteria have been selected to ensure 
that only appropriate healthy participants are 
included in the study (see Section 5). 
Individuals with significant reactions after 
vaccination or AEs considered by the investigator 
to present increased risk to the participant or who 
develop exclusionary conditions during the 
conduct of the study will be excluded from 
interventions but may be followed for safety. 
Study Procedures – Venipuncture 
Venipuncture will be performed during the study. 
There is a risk of bleeding, bruising, hematoma 
formation, and infection at the venipuncture site 
and an overall risk of dizziness and fainting 
associated with the procedure. 
Only qualified nurses, physicians, nurse 
practitioners, physician’s assistants, phlebotomists, 
or medical assistants certified or otherwise 
authorized to draw blood per the standards and 
procedures of the investigative site as allowed by 
institutional, local, and state guidance will be 
allowed to draw blood to minimize local 
complications. 

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2.3.2. Benefit Assessment 
GBS6 is being developed to benefit infants through the vaccination of pregnant women. The 
current study will provide important information about interference of GBS6 and Tdap in 
nonpregnant women to inform future studies in pregnant women. Nonpregnant women may 
benefit from participation in this study from the development of GBS antibodies, which may 
protect them from GBS disease in the near future. 
Other benefits to the individual participant may include receipt of a booster Tdap and 
protection from Tdap-associated disease, physical examination by a medical provider at the 
start of the study and prior to each study vaccination, a thorough review of the participant’s 
vaccination status, and evaluation and management of some illnesses (AEs) that occur during 
participation in the study as part of protocol-specified scheduled and unscheduled 
assessments. 
2.3.3. Overall Benefit/Risk Conclusion 
The anticipated benefit (protective immunity against GBS6) that may be afforded to 
participants outweighs the potential risks in this study, including the possibility of transient 
local and systemic reactogenicity events of varying severity and possible complications from 
needlesticks (vaccination or venipuncture) for an overall favorable benefit/risk assessment. 
3. OBJECTIVES, ESTIMANDS, AND ENDPOINTS 
 
Objectives 
Estimands 
Endpoints 
Primary (Safety): 
Primary (Safety): 
Primary (Safety): 
• To describe the safety and 
tolerability of GBS6 when 
administered concomitantly with 
Tdap (GBS6+Tdap) and when 
GBS6 is administered alone 
(GBS6+placebo). 
In participants receiving at least 1 dose 
of the investigational products: 
• The proportion of participants 
reporting prompted local reactions 
within 7 days following 
investigational product 
administration. 
• Prompted local reactions (redness, 
swelling, and pain at the injection 
site). 
• Prompted systemic events 
(fever, nausea/vomiting, diarrhea, 
headache, fatigue, muscle pain, 
and joint pain). 
• The proportion of participants 
reporting prompted systemic events 
within 7 days following 
investigational product 
administration. 
• AEs. 
• MAEs and SAEs. 
• The proportion of participants 
reporting adverse events (AEs) 
through 1 month following 
investigational product 
administration. 
• The proportion of participants 
reporting medically attended 
adverse events (MAEs) and serious 
adverse events (SAEs) through 
6 months following investigational 
product administration. 

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Objectives 
Estimands 
Endpoints 
Primary (Immunogenicity): 
Primary (Immunogenicity): 
Primary (Immunogenicity): 
• To describe the immune responses 
induced by Tdap when 
administered concomitantly with 
GBS6 (GBS6+Tdap) compared to 
the immune responses induced by 
Tdap (placebo+Tdap) alone. 
In participants receiving all doses of 
the investigational products and in 
compliance with the key protocol 
criteria (evaluable participants): 
• The difference in proportions of 
participants with anti–tetanus 
toxoid antibody concentrations 
≥0.1 IU/mL measured 1 month 
after vaccination between the 
GBS6+Tdap group and the 
placebo+Tdap group. 
• The difference in proportions of 
participants with anti–diphtheria 
toxoid antibody concentrations 
≥0.1 IU/mL measured 1 month 
after vaccination between the 
GBS6+Tdap group and the 
placebo+Tdap group. 
• Geometric mean ratio (GMR), 
estimated by the GMR of 
anti–pertussis toxin antibodies 
from the GBS6+Tdap group to the 
placebo+Tdap group measured 
1 month after vaccination. 
• GMR, estimated by the GMR of 
anti–filamentous hemagglutinin 
(anti-FHA) antibodies from the 
GBS6+Tdap group to the 
placebo+Tdap group measured 
1 month after vaccination. 
• 
GMR, estimated by the GMR of 
antipertactin (anti-PRN) 
antibodies from the GBS6+Tdap 
group to the placebo+Tdap group 
measured 1 month after 
vaccination. 
• Anti–tetanus toxoid and anti– 
diphtheria toxoid antibodies and 
anti–pertussis component 
(pertussis toxin, FHA, and PRN) 
antibodies. 
• To describe the immune responses 
induced by GBS6 when 
administered concomitantly with 
Tdap (GBS6+Tdap) compared to 
the immune responses induced by 
GBS6 (GBS6+placebo) alone. 
• 
GBS capsular polysaccharide 
(CPS) serotype-specific IgG 
GMR, estimated by the GMR of 
GBS CPS serotype-specific IgG 
antibodies from the GBS6+Tdap 
group to the GBS6+placebo 
group measured 1 month after 
vaccination. 
• GBS CPS serotype-specific IgG 
antibody concentration. 
Secondary: 
Secondary: 
Secondary: 
• N/A 
• N/A 
• N/A 

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Objectives 
Estimands 
Endpoints 
Exploratory (Immunogenicity): 
Exploratory (Immunogenicity): 
Exploratory (Immunogenicity): 
• To further describe the immune 
responses elicited by Tdap when 
administered concomitantly with 
GBS6 (GBS6+Tdap) compared to 
Tdap (placebo+Tdap) alone. 
In participants receiving all doses of 
the investigational products and in 
compliance with the key protocol 
criteria (evaluable participants): 
• Proportions of participants with 
anti–tetanus toxoid and 
anti–diphtheria toxoid antibody 
concentrations ≥0.1 IU/mL 
measured before vaccination 
and 1 month after vaccination 
for both the GBS6+Tdap group 
and the placebo+Tdap group. 
• Proportions of participants with 
anti–tetanus toxoid and 
anti–diphtheria toxoid antibody 
concentrations ≥1.0 IU/mL 
measured before vaccination 
and 1 month after vaccination 
for both the GBS6+Tdap group 
and the placebo+Tdap group. 
• The differences in proportions 
of participants with anti–tetanus 
toxoid and anti–diphtheria 
toxoid antibody concentrations 
≥1.0 IU/mL measured 1 month 
after vaccination between the 
GBS6+Tdap group and the 
placebo+Tdap group. 
• GMCs of anti–tetanus toxoid, 
anti–diphtheria toxoid, and 
anti–pertussis component 
(pertussis toxin, FHA, PRN, 
and FIM) antibodies measured 
before vaccination and 1 month 
after vaccination for both the 
GBS6+Tdap group and the 
placebo+Tdap group. 
• Geometric mean fold rises 
(GMFRs) of anti–tetanus 
toxoid, anti–diphtheria toxoid, 
and anti–pertussis component 
(pertussis toxin, FHA, PRN, 
and FIM) antibodies measured 
from before vaccination to 
1 month after vaccination for 
both the GBS6+Tdap group and 
the placebo+Tdap group. 
• Anti–tetanus toxoid, 
anti–diphtheria toxoid, and anti–
pertussis component (pertussis 
toxin, FHA, PRN, and FIM) 
antibody concentrations. 

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Objectives 
Estimands 
Endpoints 
• To further describe the immune 
responses elicited by GBS6 when 
administered concomitantly with 
Tdap (GBS6+Tdap) compared to 
GBS6 (GBS6+placebo) alone. 
• GBS CPS serotype-specific IgG 
GMCs measured before and 1 
month after vaccination for both 
the GBS6+Tdap group and the 
GBS6+placebo group. 
• GBS CPS serotype-specific IgG 
GMFRs measured from before 
vaccination to 1 month after 
vaccination for both the 
GBS6+Tdap group and the 
GBS6+placebo group. 
• GBS CPS serotype-specific IgG 
antibody concentrations. 
 
4. STUDY DESIGN 
4.1. Overall Design 
This Phase 2, multicenter, placebo-controlled, randomized, observer-blinded study will enroll 
approximately 300 healthy nonpregnant women from US investigative sites, 18 through 49 
years of age, who will be randomized to evaluate concomitant administration of GBS6 and 
Tdap. Participants will be randomized in a 1:1:1 ratio to receive 20 µg GBS6 and 
concomitant Tdap, 20 µg GBS6 and placebo, or Tdap and placebo. 
Participants will have blood drawn prior to vaccination (Visit 1) and at 1 month after 
vaccination (Visit 2). E-diaries will be used to collect prompted local reaction and systemic 
event data for 7 days after vaccination (Days 1 through 7, where Day 1 is the day of 
vaccination). AEs will be collected through Visit 2. MAEs and SAEs will be collected 
through Visit 3. 
Participants will take part in the study from enrollment to 6 months after vaccination. 
An E-DMC will be utilized. 
4.2. Scientific Rationale for Study Design 
Refer to Section 2.1. 
Human reproductive safety data are limited for GBS6. 
Based on the pharmacology of the compound and data from reproductive toxicity in animals, 
there is no expectation of human teratogenicity. However, as data in humans are limited, the 
use of a highly effective method of contraception is required (see Appendix 4). 
4.3. Justification for Dose 
The dose of vaccine that will be used in this study was determined following assessment of 
safety and immunogenicity data from the FIH study (C1091001) and Study C1091002. 

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The FIH study was conducted in healthy nonpregnant women and healthy men in the US and 
assessed the safety and immunogenicity of 3 different dose levels of GBS6 (5, 10, or 
20 µg/serotype, formulated with or without AlPO4). GBS6 was safe and well-tolerated and 
elicited robust immune responses at all dose levels and formulations. The highest dose 
(20 µg/serotype, formulated without AlPO4) is selected for this study, as this is the 
dose/formulation that has been selected for future licensure studies and has shown an 
acceptable safety profile, the greatest consistent postvaccination immune responses in 
pregnant women, and measurable IgG antibody concentrations in infants in Study C1091002. 
4.4. End of Study Definition 
The end of the study is defined as the date of the last visit of the last participant in the study. 
5. STUDY POPULATION 
This study can fulfill its objectives only if appropriate participants are enrolled. The 
following eligibility criteria are designed to select participants for whom participation in the 
study is considered appropriate. All relevant medical and nonmedical conditions should be 
taken into consideration when deciding whether a particular participant is suitable for this 
protocol. 
Prospective approval of protocol deviations to recruitment and enrollment criteria, also 
known as protocol waivers or exemptions, is not permitted. 
5.1. Inclusion Criteria 
Participants are eligible to be included in the study only if all of the following criteria apply: 
Age and Sex: 
1. Healthy women ≥18 and ≤49 years of age. Refer to Appendix 4 for reproductive criteria 
for female participants (Section 10.4.1). 
Type of Participant and Disease Characteristics: 
2. Participants who are willing and able to comply with scheduled visits, investigational 
plan, laboratory tests, lifestyle considerations, and other study procedures, including 
completion of the e-diary from Day 1 to Day 7 following administration of 
investigational product. 
3. Healthy females at enrollment who are determined by medical history, physical 
examination, and clinical judgment of the investigator to be eligible for inclusion in the 
study. 
4. Expected to be available for the duration of the study and who can be contacted by 
telephone during study participation. 

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Informed Consent: 
5. Capable of giving personal signed informed consent as described in Appendix 1, which 
includes compliance with the requirements and restrictions listed in the ICD and in this 
protocol. 
5.2. Exclusion Criteria 
Participants are excluded from the study if any of the following criteria apply: 
1. Pregnant female participants; breastfeeding female participants; positive urine pregnancy 
test for women of childbearing potential (WOCBP) at Visit 1 (prior to vaccination); and 
WOCBP who are, in the opinion of the investigator, sexually active and at risk for 
pregnancy; and WOCBP who are unwilling or unable to use effective methods of 
contraception as outlined in this protocol from the signing of the informed consent until 
at least 28 days after the last dose of investigational product. 
Medical Conditions: 
2. History of severe adverse reaction associated with a vaccine and/or severe allergic 
reaction (eg, anaphylaxis) to any component of the investigational product or any 
diphtheria toxoid–containing or CRM197-containing vaccine. 
3. History of microbiologically proven invasive disease caused by group B streptococcus. 
4. Immunocompromised participants with known or suspected immunodeficiency. 
5. Bleeding diathesis or condition associated with prolonged bleeding that would in the 
opinion of the investigator contraindicate intramuscular injection. 
6. Other medical or psychiatric condition including recent (within the past year) or active 
suicidal ideation/behavior or laboratory abnormality that may increase the risk of study 
participation or, in the investigator’s judgment, make the participant inappropriate for the 
study. 
Prior/Concomitant Therapy: 
7. Previous vaccination with any licensed or investigational GBS vaccine, or planned 
receipt during the participant’s participation in the study (through the 6-month follow-up 
visit [Visit 3]). 
8. Vaccination within 5 years with tetanus and diphtheria toxoids and acellular pertussis– 
containing vaccines (Tdap) before investigational product administration. 
9. Participants who receive treatment with immunosuppressive therapy, including cytotoxic 
agents or systemic corticosteroids, eg, for cancer or an autoimmune disease, or planned 
receipt through the 1-month follow-up visit (Visit 2). 

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10. Vaccination with diphtheria- or CRM197-containing vaccine(s) from 6 months before 
investigational product administration, or planned receipt through the 1-month follow-up 
visit. 
11. Receipt or planned receipt of blood/plasma products or immunoglobulin, from 60 days 
before investigational product administration through the 1-month follow-up visit. 
Prior/Concurrent Clinical Study Experience: 
12. Participation in other studies involving investigational drug(s) within 28 days prior to 
study entry and/or during study participation. Participation in purely observational 
studies is acceptable. 
Diagnostic Assessments: 
Not applicable. 
Other Exclusions: 
13. Investigator site staff or Pfizer employees directly involved in the conduct of the study, 
site staff otherwise supervised by the investigator, and their respective family members. 
5.3. Lifestyle Considerations 
5.3.1. Contraception 
The investigator or his or her designee, in consultation with the participant, will confirm that 
the participant has selected an appropriate method of contraception for the individual 
participant and her partner(s) from the permitted list of contraception methods 
(see Appendix 4, Section 10.4.3) and will confirm that the participant has been instructed in 
its consistent and correct use. At time points indicated in the SoA, the investigator or 
designee will inform the participant of the need to use highly effective contraception 
consistently and correctly and document the conversation and the participant’s affirmation in 
the participant’s chart (participants need to affirm their consistent and correct use of at least 1 
of the selected methods of contraception) considering that their risk for pregnancy may have 
changed since the last visit. In addition, the investigator or designee will instruct the 
participant to call immediately if the selected contraception method is discontinued or if 
pregnancy is known or suspected in the participant or partner. 
5.4. Screen Failures 
Screen failures are defined as participants who consent to participate in the clinical study but 
are not subsequently randomly assigned to study intervention. A minimal set of screen 
failure information is required to ensure transparent reporting of screen failure participants to 
meet the CONSORT publishing requirements and to respond to queries from regulatory 
authorities. Minimal information includes demography, screen failure details, eligibility 
criteria, and any SAE. 

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Individuals who do not meet the criteria for participation in this study (screen failure) may be 
rescreened under a different participant number if they later meet eligibility criteria. 
5.5. Criteria for Temporarily Delaying Enrollment/Randomization/Administration of 
Study Intervention 
5.5.1. Temporary Delay Criteria 
The following conditions are temporary or self-limiting and a participant may be vaccinated 
and/or have blood drawn in the study once the condition(s) has/have resolved and no other 
exclusion criteria are met. The prevaccination immunogenicity blood draw and vaccination 
should take place on the same day (Visit 1). 
5.5.1.1. Criteria for Temporarily Delaying Vaccine Administration 
• Current febrile illness (body temperature ≥100.4°F [≥38.0°C]) or other acute illness 
within 48 hours before investigational product administration. 
• Receipt of any inactivated vaccine or otherwise nonlive vaccine within 14 days and any 
live vaccine within 28 days before investigational product administration. 
• Receipt of short-term (<14 days) systemic corticosteroids. Investigational product 
administration should be delayed until systemic corticosteroid use has been discontinued 
for at least 30 days. Inhaled/nebulized, intra-articular, intrabursal, or topical (skin or 
eyes) corticosteroids are permitted. 
5.5.1.2. Criteria for Temporarily Delaying Blood Draw 
• Receipt of antibiotic therapy within 72 hours before blood draw. Note: Topical 
antibiotics are permitted. 
6. STUDY INTERVENTION(S) AND CONCOMITANT THERAPY 
Study intervention is defined as any investigational intervention(s), marketed product(s), 
placebo, medical device(s), or study procedure(s) intended to be administered to a study 
participant according to the study protocol. 
For the purposes of this protocol, the term investigational product may be used 
synonymously with study intervention. 
6.1. Study Intervention(s) Administered 
For this study, the investigational products are GBS6 (20 µg CPS/serotype/dose, which is 
equivalent to a 120-µg/0.5-mL dose), Tdap, and placebo (normal saline). 

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6.1.1. GBS6 
GBS6 is composed of serotypes Ia, Ib, II, III, IV, and V CPSs individually conjugated to the 
CRM197 carrier protein. CCI 
 
. There is 1 dose level (20 µg CPS/serotype/dose per vaccine dose of 
120 µg). 
CCI 
 designed to 
deliver the intended dose in a 0.5-mL injection volume. 
6.1.2. Tdap 
US-licensed Tdap will be provided by the sponsor to each study site. 
Investigational sites will be provided with details of which US-licensed Tdap will be 
provided prior to the start of enrollment. The active ingredients of Tdap will contain the 
following (per 0.5-mL dose): 5 Lf (limits of flocculation) of TTd, 2 Lf of DTd, acellular 
pertussis antigens (2.5 µg of inactivated pertussis toxin, 5 µg of FHA, and 3 µg of PRN, 5 µg 
of FIM). 
The Tdap will also contain the following excipient concentrations: 1.5 mg AlPO4, ≤5 µg of 
residual formaldehyde, <50 ng residual glutaraldehyde, and 3.3 mg phenoxyethanol. 
Note: The stopper of the Tdap vial may contain natural rubber latex. 
6.1.3. Placebo 
The placebo for the GBS6 vaccine and Tdap will be a sterile normal saline solution for 
injection (0.9% NaCl injection, in a 0.5-mL dose). 
Placebo will be provided by the sponsor to each study site. 
Placebo will be packaged within cartons labeled by Pfizer or its designee in accordance with 
current guidelines and applicable local and legal regulatory requirements. 
6.1.4. Administration 
Participants will receive 2 injections at Visit 1 in accordance with the study’s SoA. 
A 120-µg dose of GBS6 (0.5 mL) and Tdap, a 120-µg dose of GBS6 (0.5 mL) and normal 
saline placebo, or normal saline placebo and Tdap will be administered intramuscularly by an 
unblinded site staff member or designee. 

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Location of Injection at Visit 1 
 
Formulation 
Site of Vaccination 
GBS6 (20 µg CPS/serotype/dose) 
Tdap 
Left deltoid muscle 
Right deltoid muscle 
GBS6 (20 µg CPS/serotype/dose) 
Placebo 
Left deltoid muscle 
Right deltoid muscle 
Placebo 
Tdap 
Left deltoid muscle 
Right deltoid muscle 
 
Standard vaccination practices must be observed and vaccine must not be injected into blood 
vessels. Appropriate medication and other supportive measures for management of an acute 
hypersensitivity reaction should be available in accordance with local guidelines for standard 
immunization practices. 
Administration of study interventions should be performed by an appropriately qualified, 
GCP-trained, and vaccine-experienced member of the study staff (eg, physician, nurse, 
physician’s assistant, nurse practitioner, pharmacist, or medical assistant) as allowed by 
local, state, and institutional guidance. 
Study intervention administration details will be recorded on the CRF. 
6.2. Preparation/Handling/Storage/Accountability 
1. The investigator or designee must confirm appropriate temperature conditions have been 
maintained during transit for all study interventions received and any discrepancies are 
reported and resolved before use of the study intervention. 
2. Investigational product will be shipped at +2°C to +8°C to each study site after required 
regulatory and legal documents have been received by the sponsor. Upon receipt 
at the study site, the investigational product should be immediately transferred to 
a +2°C to +8°C temperature-monitored refrigerator for storage. 
3. Only participants enrolled in the study may receive study intervention and only 
authorized site staff may supply or administer study intervention. All study interventions 
must be stored in a secure, environmentally controlled, and monitored (manual or 
automated recording) area in accordance with the labeled storage conditions with access 
limited to the investigator and authorized site staff. At a minimum, daily minimum and 
maximum temperatures for all site storage locations must be documented and available 
upon request. Data for nonworking days must indicate the minimum and maximum 
temperatures since previously documented for all site storage locations upon return to 
business. 

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4. Any excursions from the study intervention label storage conditions should be reported to 
Pfizer upon discovery along with any actions taken. The site should actively pursue 
options for returning the study intervention to the storage conditions described in the 
labeling, as soon as possible. Once an excursion is identified, the study intervention must 
be quarantined and not used until Pfizer provides permission to use the study 
intervention. Specific details regarding the definition of an excursion and information the 
site should report for each excursion will be provided to the site in the IP manual. 
5. Any storage conditions stated in the SRSD will be superseded by the storage conditions 
stated on the label. 
6. Study interventions should be stored in their original containers. 
7. See the IP manual for storage conditions of the study intervention. 
8. The investigator, institution, or the head of the medical institution (where applicable) is 
responsible for study intervention accountability, reconciliation, and record maintenance 
(ie, receipt, reconciliation, and final disposition records), such as the IPAL or 
sponsor-approved equivalent. All study interventions will be accounted for using a study 
intervention accountability form/record. 
9. Further guidance and information for the final disposition of unused study interventions 
are provided in the IP manual. All destruction must be adequately documented. If 
destruction is authorized to take place at the investigator site, the investigator must ensure 
that the materials are destroyed in compliance with applicable environmental regulations, 
institutional policy, and any special instructions provided by Pfizer. 
Upon identification of a product complaint, notify the sponsor within 1 business day of 
discovery as described in the IP manual. 
6.2.1. Preparation and Dispensing 
See the IP manual for instructions on how to prepare the investigational products for 
administration. Investigational products should be prepared and dispensed by an 
appropriately qualified and experienced unblinded member of the study staff (eg, physician, 
nurse, physician’s assistant, nurse practitioner, pharmacy assistant/technician, or pharmacist) 
as allowed by local, state, and institutional guidance. 

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6.3. Measures to Minimize Bias: Randomization and Blinding 
6.3.1. Allocation to Study Intervention 
Allocation (randomization) of participants to investigational product groups will proceed 
through the use of an IRT system (IWR). The unblinded site personnel will be required to 
enter or select information including but not limited to the user’s ID and password, the 
protocol number, and the participant number. The unblinded site personnel will then be 
provided with an investigational product assignment, randomization number, and DU or 
container number when study intervention is being supplied via the IRT system. The IRT 
system will provide a confirmation report containing the participant number, randomization 
number, and DU or container number assigned. The confirmation report must be stored by 
the unblinded site personnel in the unblinded site files. 
Study intervention will be dispensed at Visit 1 only as summarized in the SoA. 
The study-specific IRT reference manual and IP manual will provide the contact information 
and further details on the use of the IRT system. 
6.3.2. Blinding of the Site Personnel 
This is an observer-blinded study, as the appearance of GBS6, Tdap, and placebo will not be 
matched. The study staff dispensing, preparing, and administering the vaccine will be 
unblinded, but all other study personnel, including the principal investigator and the 
participant, will be blinded. The principal investigator will assign the responsibility of 
unblinded dispenser and unblinded administrator to persons who will not participate in the 
evaluation of any study participant. More than 1 unblinded dispenser/administrator may be 
assigned. A member of the study site staff or clinic pharmacy should fulfill this role. 
Contact between the unblinded dispenser/administrator and study participants should be kept 
to a minimum. The investigator, study coordinator, and any site staff other than the 
unblinded dispenser/administrator must not be allowed to know the investigational product 
assigned to any study participant and must not be allowed to see the investigational product 
containers. 
6.3.3. Blinding of the Sponsor 
Sponsor study team members will remain blinded to vaccine assigned/received at the 
participant level. In an event that unblinded results need to be submitted for regulatory 
communications prior to study team unblinding, efforts will be made to ensure study team 
members involved in participant assessments are blinded. 
Laboratory personnel performing the immunologic assays will remain blinded to vaccine 
assigned/received throughout the study. 

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6.3.4. Breaking the Blind 
The IRT will be programmed with blind-breaking instructions. In case of an emergency, the 
investigator has the sole responsibility for determining if unblinding of a participant’s 
investigational product assignment is warranted. Participant safety must always be the first 
consideration in making such a determination. If the investigator decides that unblinding is 
warranted, the investigator should make every effort to contact the sponsor prior to 
unblinding a participant’s investigational product assignment unless this could delay further 
management of the participant. If a participant’s investigational product assignment is 
unblinded, the sponsor must be notified within 24 hours after breaking the blind. The date 
and reason that the blind was broken must be recorded in the source documentation and CRF. 
The study-specific IRT reference manual and IP manual will provide the contact information 
and further details on the use of the IRT system. 
6.4. Study Intervention Compliance 
All doses of investigational product will be administered by the appropriately qualified and 
designated study staff at the investigator site. 
6.5. Concomitant Therapy 
6.5.1. Prohibited Nonstudy Vaccines and Medications During the Study 
• Nonstudy investigational vaccines, drugs, or medical devices are prohibited during the 
course of the study. 
• Nonstudy diphtheria- and CRM197-containing vaccines, blood/plasma products or 
immunoglobulins, and immunosuppressive therapy are prohibited during the course of 
the study. 
• Other nonstudy vaccines may not be given concomitantly with the investigational product 
or within 14 days after investigational product administration (except during an outbreak 
or pandemic situation). 
6.5.2. Permitted Nonstudy Vaccines and Medications During the Study 
• Licensed influenza vaccine may be given during the study 14 days after investigational 
product administration. 
• If medically necessary (eg, pandemic), licensed vaccines may be given at any time. 
• Inhaled/nebulized, intra-articular, intrabursal, or topical (skin or eyes) corticosteroids are 
permitted. 
• The use of antipyretics and other pain medication to treat symptoms associated with 
investigational product administration is permitted during participant participation in the 
study. 

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• The use of prophylactic antipyretic medication, while permitted, is not recommended on 
the day of the investigational product administration. 
• Any other vaccines that are medically required by local recommendations and permitted 
by the protocol may be administered concomitantly with GBS6 and/or Tdap but must be 
given in a different limb. 
• Hormonal contraceptives that meet the requirements of this study are allowed to be used 
in participants who are WOCBP (see Appendix 4). 
6.5.3. Recording Nonstudy Vaccinations and Concomitant Medications 
The name and date of administration for all nonstudy vaccinations received from the time of 
signing of the ICD to Visit 3 will be collected and recorded in the CRF. Antibiotic treatment 
taken from the signing of the ICD to Visit 3 will be recorded. 
Details of any medications that the participant is currently taking for medical conditions at 
enrollment (time of signing of the ICD at Visit 1) will be recorded in the CRF. Additionally, 
only medications taken to treat AEs from the signing of the ICD through Visit 2 and MAEs 
and SAEs from the signing of the ICD through Visit 3 will be recorded in the CRF 
(per Section 8.3.1). 
6.6. Dose Modification 
Not applicable. 
6.7. Intervention After the End of the Study 
No intervention will be provided to study participants at the end of the study. 
7. DISCONTINUATION OF STUDY INTERVENTION AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL 
7.1. Discontinuation of Study Intervention 
Since this is a single-dose study, this section is not applicable. 
7.2. Participant Discontinuation/Withdrawal From the Study 
A participant may withdraw from the study at any time at his/her own request. Reasons for 
discontinuation from the study include the following: 
• Withdrawn consent (refused further follow-up); 
• Lost to follow-up; 
• Medication error without associated AE; 
• Death; 

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• Study terminated by sponsor; 
• AEs; 
• Protocol violation; 
• Pregnancy; 
• No longer meets eligibility criteria. 
After investigational product administration at Visit 1, participants who request to 
discontinue further study procedures (eg, blood draw) at an upcoming visit will be asked to 
remain in the study for protocol-specified safety follow-up procedures. The only exception 
to this is when a participant specifically withdraws consent for any further contact with her. 
If a participant withdraws from the study, she may request destruction of any remaining 
samples taken and not tested, and the investigator must document any such requests in the 
site study records and notify the sponsor accordingly. 
If the participant withdraws from the study and also withdraws consent (see Section 7.2.1) 
for disclosure of future information, no further evaluations should be performed and no 
additional data should be collected. The sponsor may retain and continue to use any data 
collected before such withdrawal of consent. 
When a participant withdraws from the study because of an SAE, the SAE must be recorded 
on the CRF and reported on the Vaccine SAE Reporting Form. 
Lack of completion of all or any of the withdrawal/early termination procedures will not be 
viewed as protocol deviations so long as the participant’s safety was preserved. 
Participants who have received the investigational product will not be replaced regardless of 
the reason for withdrawal. 
7.2.1. Withdrawal of Consent 
Participants who request to discontinue receipt of study intervention will remain in the study 
and must continue to be followed for protocol-specified follow-up procedures. The only 
exception to this is when a participant specifically withdraws consent for any further contact 
with her or persons previously authorized by the participant to provide this information. 
Participants should notify the investigator in writing of the decision to withdraw consent 
from future follow-up, whenever possible. The withdrawal of consent should be explained in 
detail in the medical records by the investigator as to whether the withdrawal is only from 
further receipt of the study intervention or also from the study procedures and/or 
posttreatment study follow-up, and entered on the appropriate CRF page. In the event that 
vital status (whether the participant is alive or dead) is being measured, publicly available 
information should be used to determine vital status only as appropriately directed in 
accordance with local law. 

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7.3. Lost to Follow-up 
A participant will be considered lost to follow-up if she repeatedly fails to return for 
scheduled visits and is unable to be contacted by the study site. 
The following actions must be taken if a participant fails to return to the clinic for a required 
study visit or cannot be reached for scheduled telephone call: 
• The site must attempt to contact the participant and reschedule the missed visit as 
soon as possible and counsel the participant on the importance of maintaining the 
assigned visit schedule and ascertain whether or not the participant wishes to and/or 
should continue in the study; 
• Before a participant is deemed lost to follow-up, the investigator or designee must 
make every effort to regain contact with the participant (where possible, 3 telephone 
calls and, if necessary, a certified letter to the participant’s last known mailing 
address or local equivalent methods). These contact attempts should be documented 
in the participant’s medical record; 
• Should the participant continue to be unreachable, she will be considered to have 
withdrawn from the study. 
8. STUDY ASSESSMENTS AND PROCEDURES 
The investigator (or an appropriate delegate at the investigator site) must obtain a signed and 
dated ICD before performing any study-specific procedures. 
The date of birth will be collected to critically evaluate the immune response and safety 
profile by age. 
Study procedures and their timing are summarized in the SoA. Protocol waivers or 
exemptions are not allowed. 
Safety issues should be discussed with the sponsor immediately upon occurrence or 
awareness to determine whether the participant should continue or discontinue study 
intervention. 
Adherence to the study design requirements, including those specified in the SoA, is essential 
and required for study conduct. 
All screening evaluations must be completed and reviewed to confirm that potential 
participants meet all eligibility criteria. The investigator will maintain a screening log to 
record details of all participants screened and to confirm eligibility or record reasons for 
screening failure, as applicable. 

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Every effort should be made to ensure that protocol-required tests and procedures are 
completed as described. However, it is anticipated that from time to time there may be 
circumstances outside the control of the investigator that may make it unfeasible to perform 
the test. In these cases, the investigator must take all steps necessary to ensure the safety 
and well-being of the participant. When a protocol-required test cannot be performed, the 
investigator will document the reason for the missed test and any corrective and preventive 
actions that he/she has taken to ensure that required processes are adhered to as soon as 
possible. The study team must be informed of these incidents in a timely manner. 
For samples being collected and shipped, detailed collection, processing, storage, and 
shipment instructions and contact information will be provided to the investigator site prior 
to initiation of the study. 
8.1. Efficacy and/or Immunogenicity Assessments 
Blood samples (approximately 50 mL/visit) for immunogenicity assessments will be 
collected from all participants prior to vaccination (Day 1) and at 1 month after vaccination 
(Visit 2) 
Sample collection, processing, storage, and shipping information can be found in the ISF or 
equivalent manual. Sera will be used for immunogenicity assessments, assay development, 
and routine assay maintenance. 
8.1.1. GBS Vaccine Antibody Testing 
Concentrations of anticapsular IgG for the 6 serotypes (Ia, Ib, II, III, IV, and V) will be 
determined from the GBS6+Tdap and GBS6+placebo groups for each blood sample at Day 1 
and at 1 month after vaccination and reported as IgG concentrations. 
Participants from these 2 groups will be identified by an independent unblinded statistician; 
additional participants from the placebo+Tdap group may be included in order to maintain 
the blinding of randomization assignment. 
8.1.2. Tdap Antibody Testing 
Sera will be collected from the coadministration and placebo+Tdap groups and they will be 
assayed for IgG antibodies to Tdap antigens in a multiplexed Luminex bead-based assay 
(DTP-6 IgG). IgG levels to diphtheria, tetanus, and pertussis antigens (pertussis toxin, PRN, 
FHA, and FIM) will be measured and reported in either IU/mL (diphtheria and tetanus) or 
EU/mL (pertussis toxin, FHA, FIM and PRN). 
Participants from these 2 groups will be identified by an independent unblinded statistician; 
additional participants from the GBS6+placebo group may be included in order to maintain 
the blinding of randomization assignment. 
Immunogenicity assays will be performed at Pfizer Vaccine Research & Development 
Laboratory located at 401 North Middletown Road, Pearl River, NY 10965 and/or at a 
facility designated by Pfizer. 

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8.1.3. Biological Samples 
Serum samples will be used only for scientific research. Each sample will be labeled with a 
code so that the laboratory personnel testing the samples will not know the participant’s 
identity. Samples that remain after performing assays outlined in the protocol may be stored 
by Pfizer. Unless a time limitation is required by local regulations or ethical requirements, 
the samples will be stored for up to 15 years after the end of the study and then destroyed. 
If allowed by the ICD, stored samples may be used for additional testing to better understand 
the immune responses to the vaccine(s) under study in this protocol, to inform the 
development of other products, and/or for vaccine-related assay work supporting vaccine 
programs. No testing of the participant’s genetic material will be performed. 
The participant may request that her samples, if still identifiable, be destroyed at any time; 
however, any data already collected from those samples will still be used for this research. 
The biological samples may be shared with other researchers as long as confidentiality is 
maintained and no testing of the participant’s genetic material is performed. 
8.2. Safety Assessments 
Planned time points for all safety assessments are provided in the SoA. Unscheduled clinical 
laboratory measurements may be obtained at any time during the study to assess any 
perceived safety issues. 
8.2.1. Participant E-Diary 
Participants will be required to use an e-diary, based on appropriate technology, and 
will be asked to monitor and record local reactions, systemic events, temperature, and 
antipyretic/pain medication used to treat symptoms each evening for 7 days following 
vaccination. Participants may be able to utilize their own devices to access this technology, 
or use a device provided by the sponsor. This system, hereafter referred to as the 
participant’s e-diary, allows recording of these assessments only within a fixed time window, 
thus providing the accurate representation of the participant’s experience at that time. Data 
on local reactions, systemic events, temperature, and antipyretic/pain medication used to treat 
symptoms reported on the e-diary will be transferred electronically to the e-diary vendor, 
where they will be available for review by investigators, their qualified designees, and 
sponsor staff at all times via an internet-based portal. At intervals agreed to by the vendor 
and Pfizer, these data will be transferred electronically to Pfizer for analysis and reporting. 
These data do not need to be reported by the investigator in the CRF. However, if a 
participant withdraws because of prompted events reported in the e-diary, the event(s) should 
be recorded on the AE page of the CRF, regardless of whether the investigator considers the 
event(s) to be clinically significant. 
Investigators (or appropriately qualified designee) are required to review the e-diary data 
online to evaluate participant compliance and as part of the ongoing safety review. 

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The investigator or designee must contact the participant in order to obtain stop dates for any 
reactions ongoing on the last day that the e-diary was completed. The stop dates should be 
documented in the source documents and the information entered in the CRF. 
8.2.2. Grading Scale for Prompted Events 
The grading scales used in this study to assess AEs as described below are based on concepts 
outlined in the FDA CBER guidelines on toxicity grading scales for healthy adult volunteers 
enrolled in preventive vaccine clinical trials.36 
8.2.2.1. Local Reactions 
From Day 1 to Day 7, where Day 1 is the day of vaccination, participants will be asked to 
assess redness, swelling, and pain at the injection site of the left arm and to record the 
symptoms in the e-diary in the evening. Redness and swelling of the injection site of the left 
arm will be measured and recorded in measuring device units (range: 1 to 21 and >21), and 
then categorized during analysis as mild, moderate, or severe based on the grading scale in 
Table 1. Measuring device units can be converted to centimeters according to the following 
scale: 1 measuring device unit = 0.5 cm. Pain at the vaccine injection site of the left arm will 
be assessed by the participant as mild, moderate, or severe according to the grading scale in 
Table 1. A participant with a severe (Grade 3 or above) local reaction of the left arm will be 
prompted to contact the investigator to perform an unscheduled visit and assess the reaction. 
Only an investigator is able to classify a participant’s local reaction as Grade 4, after physical 
examination of the participant or documentation from another medically qualified source 
(eg, emergency room or hospital record), or, in the case of pain at the injection site only, 
telephone contact with the participant. If a participant experiences a Grade 4 local reaction, 
the investigator must immediately notify the sponsor. Site staff will educate the participant 
regarding signs and symptoms that would prompt site contact. The procedure for notification 
of the sponsor is provided in the study documentation. 
If a local reaction persists beyond the end of the e-diary period following vaccination, the 
participant will be requested to report that information and/or any new AEs that develop to 
the investigator. The investigator will enter this additional information in the CRF. 

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Table 1. 
Local Reaction Grading Scale 
 
Mild 
(Grade 1) 
Moderate 
(Grade 2) 
Severe 
(Grade 3)a 
Grade 4b 
Pain at injection 
site 
Does not interfere 
with activity 
Repeated use of 
nonnarcotic pain 
reliever >24 hours 
or interferes with 
activity 
Any use of narcotic 
pain reliever or 
prevents daily 
activityc 
Emergency room 
visit or 
hospitalization for 
severe pain at the 
injection site 
Erythema/ 
redness 
>2.0 cm to 5.0 cm 
(5 to 10 measuring 
device units) 
>5.0 cm to 10.0 cm 
(11 to 20 measuring 
device units) 
>10.0 cm 
(>20 measuring 
device units) 
Necrosis or 
exfoliative 
dermatitis 
Induration/ 
swelling 
>2.0 cm to 5.0 cm 
(5 to 10 measuring 
device units) 
>5.0 cm to 10.0 cm 
(11 to 20 measuring 
device units) 
>10.0 cm 
(>20 measuring 
device units) 
Necrosis 
a. 
Participants experiencing ≥ Grade 3 local reactions are to be seen by the study site. Refer to the 
Unscheduled Visits section (Section 8.11.4) for further guidance. 
b. Grade 4 assessment should be made by the investigator. Grade 4 will not be collected in the electronic 
diary but will be recorded as an AE on the case report form. 
c. 
Prevents daily activity, ie, results in missed days of work or school or is otherwise incapacitating, or 
includes use of narcotics for analgesia. 
 
8.2.2.2. Systemic Events 
From Day 1 to Day 7, where Day 1 is the day of vaccination, participants will be asked to 
assess nausea/vomiting, diarrhea, headache, fatigue, muscle pain, and joint pain and to 
record the symptoms in the e-diary in the evening. The symptoms will be assessed by 
the participant as mild, moderate, or severe according to the grading scale in Table 2. 
Participants will also be instructed to contact site staff if they experience any possible 
Grade 4 prompted systemic event (ie, emergency room visit or hospitalization for 
nausea/vomiting, diarrhea, headache, fatigue, muscle pain, or joint pain) within 7 days after 
vaccination. Study staff may also contact the participant to obtain additional information on 
Grade 3 events entered into the e-diary. 
Only an investigator is able to classify a participant’s systemic event as Grade 4, after 
physical examination of the participant or documentation from another medically qualified 
source (eg, emergency room or hospital record) or telephone contact with the participant. If 
a participant experiences a Grade 4 systemic event, the investigator must immediately notify 
the sponsor. The procedure for notification of the sponsor is provided in the study 
documentation. 
Further, if a systemic event persists beyond the end of the e-diary period following 
vaccination, the participant will be requested to report that information and/or any new AEs 
that develop to the investigator. The investigator will enter this additional information in the 
CRF. 

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Table 2. 
Systemic Event Grading Scale 
 
Mild 
(Grade 1) 
Moderate 
(Grade 2) 
Severe 
(Grade 3)a 
Grade 4b 
Nausea/vomiting 
No interference with 
activity or 1-2 times 
in 24 hours 
Some interference 
with activity or >2 
times in 24 hours 
Prevents daily 
activity; requires IV 
hydration 
Emergency room 
visit or 
hospitalization for 
hypotensive shock 
Diarrhea 
2-3 loose stools in 24 
hours 
4-5 loose stools in 24 
hours 
≥6 loose stools in 
24 hours 
Emergency room 
visit or 
hospitalization for 
severe diarrhea 
Headache 
No interference with 
activity 
Repeated use of 
nonnarcotic pain 
reliever >24 hours or 
some interference with 
activity 
Significant; any use 
of narcotic pain 
reliever or prevents 
daily activityc 
Emergency room 
visit or 
hospitalization for 
severe headache 
Fatigue 
(= tiredness in 
diaries) 
No interference with 
activity 
Some interference 
with activity 
Significant; prevents 
daily activityc 
Emergency room 
visit or 
hospitalization for 
severe fatigue 
Muscle pain 
No interference with 
activity 
Some interference 
with activity 
Significant; prevents 
daily activityc 
Emergency room 
visit or 
hospitalization for 
severe muscle pain 
Joint pain 
No interference with 
activity 
Some interference 
with activity 
Significant; prevents 
daily activityc 
Emergency room 
visit or 
hospitalization for 
severe joint pain 
a. 
Participants experiencing ≥ Grade 3 systemic events are to be seen by the study site. Refer to the 
Unscheduled Visits section (Section 8.11.4) for further guidance. 
b. Grade 4 assessment should be made by the investigator. Grade 4 will not be collected in the electronic 
diary but will be collected as an AE on the case report form. 
c. 
Prevents daily routine activity, ie, results in missed days of work or school or is otherwise incapacitating, 
or includes use of narcotics for analgesia. 
 
8.2.2.3. Fever 
In order to record information on fever, a digital thermometer will be given to the participant 
with instructions on how to measure oral temperature at home. Temperature will be 
collected in the evening daily for 7 days following vaccination (Days 1 to 7, where Day 1 is 
the day of vaccination) and at any time during the 7 days that fever is suspected. Fever is 
defined as an oral temperature of ≥100.4°F (≥38.0°C). The highest temperature for each day 
will be recorded in the e-diary. In the event of a fever on Day 7, temperature will be 
collected daily until fever has resolved (1 day of temperature less than 100.4°F [38.0°C] in 
order to collect a stop date in the CRF). A participant with a fever ≥102.1°F (≥39.0°C) will 
be prompted to contact the investigator to assess the fever and perform an unscheduled visit 
as appropriate. Study staff must also contact the participant to obtain additional information 
if a temperature of ≥102.1°F is entered into an e-diary. Temperature will be measured and 
recorded to 1 decimal place and then grouped into ranges for the analysis according to 
Table 3. 

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Table 3. 
Ranges for Fever 
 
100.4°F to 101.1°F (38.0°C to 38.4°C) 
101.2°F to 102.0°F (>38.4°C to 38.9°C) 
102.1°F to 104.0°F (>38.9°C to 40.0°C) 
>104.0°F (>40.0°C) 
 
8.2.3. Use of Antipyretic/Pain Medication 
From Day 1 to Day 7, where Day 1 is the day of vaccination, the participant will be asked to 
record the use of antipyretic and/or pain medication used to treat symptoms reported in the 
e-diary in the evening. 
8.2.4. Clinical Safety Laboratory Assessments 
Clinical safety laboratory assessments will not be collected in this study. 
8.2.5. Pregnancy Testing 
Pregnancy tests will be urine tests, but must have a sensitivity of at least 25 mIU/mL. 
Pregnancy tests will be performed in WOCBP at the times listed in the SoA, immediately 
before the administration of each vaccine dose. A negative pregnancy test result will be 
required prior to the participant’s receiving the study intervention. Pregnancy tests may also 
be repeated if requested by IRBs/ECs or if required by local regulations. In the case of a 
positive confirmed pregnancy, the participant will be withdrawn from administration of study 
intervention but may remain in the study. 
8.3. Adverse Events and Serious Adverse Events 
The definitions of an AE and an SAE can be found in Appendix 3. 
AEs may arise from symptoms or other complaints reported by the participant (or, when 
appropriate, by a caregiver, surrogate, or the participant’s legally authorized representative), 
or they may arise from clinical findings of the investigator or other healthcare providers 
(clinical signs, test results, etc). 
The investigator and any qualified designees are responsible for detecting, documenting, and 
recording events that meet the definition of an AE or SAE and remain responsible to pursue 
and obtain adequate information both to determine the outcome and to assess whether the 
event meets the criteria for classification as an SAE or caused the participant to discontinue 
the study intervention (see Section 7.1). 
Each participant will be questioned about the occurrence of AEs in a nonleading manner. 
In addition, the investigator may be requested by Pfizer Safety to obtain specific follow-up 
information in an expedited fashion. 

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8.3.1. Time Period and Frequency for Collecting AE and SAE Information 
The time period for actively eliciting and collecting AEs and SAEs (“active collection 
period”) for each participant begins from the time the participant provides informed consent, 
which is obtained before the participant’s participation in the study (ie, before undergoing 
any study-related procedure and/or receiving study intervention), through and including 
Visit 2 (1 month after vaccination) for AEs, and through and including Visit 3 (6 months 
after vaccination) for MAEs and SAEs. 
Follow-up by the investigator continues throughout and after the active collection period and 
until the AE or SAE or its sequelae resolve or stabilize at a level acceptable to the 
investigator. 
For participants who are screen failures, the active collection period ends when screen failure 
status is determined. 
If the participant withdraws from the study and also withdraws consent for the collection of 
future information, the active collection period ends when consent is withdrawn. 
If a participant permanently discontinues or temporarily discontinues study intervention 
because of an AE or SAE, the AE or SAE must be recorded on the CRF and the SAE 
reported using the Vaccine SAE Reporting Form. 
Investigators are not obligated to actively seek AEs or SAEs after the participant has 
concluded study participation. However, if the investigator learns of any SAE, including a 
death, at any time after a participant has completed the study, and he/she considers the event 
to be reasonably related to the study intervention, the investigator must promptly report the 
SAE to Pfizer using the Vaccine SAE Reporting Form. 
8.3.1.1. Reporting SAEs to Pfizer Safety 
All SAEs occurring in a participant during the active collection period as described in 
Section 8.3.1 are reported to Pfizer Safety on the Vaccine SAE Reporting Form immediately 
upon awareness and under no circumstance should this exceed 24 hours, as indicated in 
Appendix 3. The investigator will submit any updated SAE data to the sponsor within 
24 hours of it being available. 
8.3.1.2. Recording Nonserious AEs and SAEs on the CRF 
All nonserious AEs and SAEs occurring in a participant during the active collection, which 
begins after obtaining informed consent, as described in Section 8.3.1, will be recorded on 
the AE section of the CRF. 
The investigator is to record on the CRF all directly observed and all spontaneously reported 
AEs and SAEs reported by the participant. 

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8.3.2. Method of Detecting AEs and SAEs 
The method of recording, evaluating, and assessing causality of AEs and SAEs and the 
procedures for completing and transmitting SAE reports are provided in Appendix 3. 
Care will be taken not to introduce bias when detecting AEs and/or SAEs. Open-ended and 
nonleading verbal questioning of the participant is the preferred method to inquire about 
AE occurrences. 
8.3.3. Follow-up of AEs and SAEs 
After the initial AE/SAE report, the investigator is required to proactively follow each 
participant at subsequent visits/contacts. For each event, the investigator must pursue and 
obtain adequate information until resolution, stabilization, the event is otherwise explained, 
or the participant is lost to follow-up (as defined in Section 7.3). 
In general, follow-up information will include a description of the event in sufficient detail to 
allow for a complete medical assessment of the case and independent determination of 
possible causality. Any information relevant to the event, such as concomitant medications 
and illnesses, must be provided. In the case of a participant death, a summary of available 
autopsy findings must be submitted as soon as possible to Pfizer Safety. 
Further information on follow-up procedures is given in Appendix 3. 
8.3.4. Regulatory Reporting Requirements for SAEs 
Prompt notification by the investigator to the sponsor of an SAE is essential so that legal 
obligations and ethical responsibilities towards the safety of participants and the safety of a 
study intervention under clinical investigation are met. 
The sponsor has a legal responsibility to notify both the local regulatory authority and other 
regulatory agencies about the safety of a study intervention under clinical investigation. The 
sponsor will comply with country-specific regulatory requirements relating to safety 
reporting to the regulatory authority, IRBs/ECs, and investigators. 
Investigator safety reports must be prepared for SUSARs according to local regulatory 
requirements and sponsor policy and forwarded to investigators as necessary. 
An investigator who receives SUSARs or other specific safety information (eg, summary or 
listing of SAEs) from the sponsor will review and then file it along with the SRSD(s) for the 
study and will notify the IRB/EC, if appropriate according to local requirements. 

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8.3.5. Environmental Exposure, Exposure During Pregnancy or Breastfeeding, and 
Occupational Exposure 
Environmental exposure occurs when a person not enrolled in the study as a participant 
receives unplanned direct contact with or exposure to the study intervention. Such exposure 
may or may not lead to the occurrence of an AE or SAE. Persons at risk for environmental 
exposure include healthcare providers, family members, and others who may be exposed. 
An environmental exposure may include exposure during pregnancy, exposure during 
breastfeeding, and occupational exposure. 
Any such exposure to the study intervention under study are reportable to Pfizer Safety 
within 24 hours of investigator awareness. 
8.3.5.1. Exposure During Pregnancy 
An EDP occurs if: 
• A female participant is found to be pregnant while receiving or after discontinuing 
study intervention. 
• A female nonparticipant is found to be pregnant while being exposed or having been 
exposed to study intervention due to environmental exposure. Below are examples of 
environmental EDP: 
• A female family member or healthcare provider reports that she is pregnant after 
having been exposed to the study intervention by ingestion, inhalation, or skin 
contact. 
• A male family member or healthcare provider who has been exposed to the study 
intervention by ingestion, inhalation, or skin contact then exposes his female 
partner prior to or around the time of conception. 
The investigator must report EDP to Pfizer Safety within 24 hours of the investigator’s 
awareness, irrespective of whether an SAE has occurred. The initial information submitted 
should include the anticipated date of delivery (see below for information related to 
termination of pregnancy). 
• If EDP occurs in a participant, the investigator must report this information to Pfizer 
Safety on the Vaccine SAE Reporting Form and an EDP Supplemental Form, 
regardless of whether an SAE has occurred. Details of the pregnancy will be 
collected after the start of study intervention and until 6 months after vaccination. 
• If EDP occurs in the setting of environmental exposure, the investigator must report 
information to Pfizer Safety using the Vaccine SAE Reporting Form and EDP 
Supplemental Form. Since the exposure information does not pertain to the 
participant enrolled in the study, the information is not recorded on a CRF; however, 
a copy of the completed Vaccine SAE Reporting Form is maintained in the ISF. 

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Follow-up is conducted to obtain general information on the pregnancy and its outcome for 
all EDP reports with an unknown outcome. The investigator will follow the pregnancy until 
completion (or until pregnancy termination) and notify Pfizer Safety of the outcome as a 
follow-up to the initial EDP Supplemental Form. In the case of a live birth, the structural 
integrity of the neonate can be assessed at the time of birth. In the event of a termination, 
the reason(s) for termination should be specified and, if clinically possible, the structural 
integrity of the terminated fetus should be assessed by gross visual inspection (unless 
preprocedure test findings are conclusive for a congenital anomaly and the findings are 
reported). 
Abnormal pregnancy outcomes are considered SAEs. If the outcome of the pregnancy meets 
the criteria for an SAE (ie, ectopic pregnancy, spontaneous abortion, intrauterine fetal 
demise, neonatal death, or congenital anomaly in a live-born baby, a terminated fetus, an 
intrauterine fetal demise, or a neonatal death), the investigator should follow the procedures 
for reporting SAEs. Additional information about pregnancy outcomes that are reported to 
Pfizer Safety as SAEs follows: 
• Spontaneous abortion, including miscarriage and missed abortion; 
• Neonatal deaths that occur within 6 months of birth should be reported, without 
regard to causality, as SAEs. In addition, infant deaths after 6 months should be 
reported as SAEs when the investigator assesses the infant death as related or 
possibly related to exposure to the study intervention. 
Additional information regarding the EDP may be requested by the sponsor. Further 
follow-up of birth outcomes will be handled on a case-by-case basis (eg, follow-up on 
preterm infants to identify developmental delays). In the case of paternal exposure, the 
investigator will provide the participant with the Pregnant Partner Release of Information 
Form to deliver to his partner. The investigator must document in the source documents that 
the participant was given the Pregnant Partner Release of Information Form to provide to his 
partner. 
8.3.5.2. Exposure During Breastfeeding 
An exposure during breastfeeding occurs if: 
• A female participant is found to be breastfeeding while receiving or after 
discontinuing study intervention. 
• A female nonparticipant is found to be breastfeeding while being exposed or having 
been exposed to study intervention (ie, environmental exposure). An example of 
environmental exposure during breastfeeding is a female family member or 
healthcare provider who reports that she is breastfeeding after having been exposed to 
the study intervention by inhalation or skin contact. 

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The investigator must report exposure during breastfeeding to Pfizer Safety within 24 hours 
of the investigator’s awareness, irrespective of whether an SAE has occurred. The 
information must be reported using the Vaccine SAE Reporting Form. When exposure 
during breastfeeding occurs in the setting of environmental exposure, the exposure 
information does not pertain to the participant enrolled in the study, so the information is not 
recorded on a CRF. However, a copy of the completed Vaccine SAE Reporting Form is 
maintained in the ISF. 
An exposure during breastfeeding report is not created when a Pfizer drug specifically 
approved for use in breastfeeding women (eg, vitamins) is administered in accord with 
authorized use. However, if the infant experiences an SAE associated with such a drug, the 
SAE is reported together with the exposure during breastfeeding. 
8.3.5.3. Occupational Exposure 
An occupational exposure occurs when a person receives unplanned direct contact with the 
study intervention, which may or may not lead to the occurrence of an AE. Such persons 
may include healthcare providers, family members, and other roles that are involved in the 
trial participant’s care. 
The investigator must report occupational exposure to Pfizer Safety within 24 hours of the 
investigator’s awareness, regardless of whether there is an associated SAE. The information 
must be reported using the Vaccine SAE Reporting Form. Since the information does not 
pertain to a participant enrolled in the study, the information is not recorded on a CRF; 
however, a copy of the completed Vaccine SAE Reporting Form is maintained in the ISF. 
8.3.6. Cardiovascular and Death Events 
Not applicable. 
8.3.7. Disease-Related Events and/or Disease-Related Outcomes Not Qualifying as AEs 
or SAEs 
Not applicable. 
8.3.8. Adverse Events of Special Interest 
Not applicable. 
8.3.8.1. Lack of Efficacy 
Lack of efficacy in an approved indication should be reported as an SAE to Pfizer Safety. 
8.3.9. Medical Device Deficiencies 
Not applicable. 

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8.3.10. Medication Errors 
Medication errors may result from the administration or consumption of the study 
intervention by the wrong participant, or at the wrong time, or at the wrong dosage strength. 
Exposures to the study intervention under study may occur in clinical trial settings, such as 
medication errors. 
 
Safety Event 
Recorded on the CRF 
Reported on the Vaccine SAE 
Reporting Form to Pfizer Safety 
Within 24 Hours of Awareness 
Medication errors 
All (regardless of whether 
associated with an AE) 
Only if associated with an SAE 
 
Medication errors include: 
• Medication errors involving participant exposure to the study intervention; 
• Potential medication errors or uses outside of what is foreseen in the protocol that do 
or do not involve the study participant. 
Such medication errors occurring to a study participant are to be captured on the medication 
error page of the CRF, which is a specific version of the AE page. 
In the event of a medication dosing error, the sponsor should be notified within 24 hours. 
Whether or not the medication error is accompanied by an AE, as determined by the 
investigator, the medication error is recorded on the medication error page of the CRF and, if 
applicable, any associated AE(s), serious and nonserious, are recorded on the AE page of the 
CRF. 
Medication errors should be reported to Pfizer Safety within 24 hours on a Vaccine SAE 
Reporting Form only when associated with an SAE. 
Other examples include, but are not limited to: 
• The administration of expired study intervention; 
• The administration of an incorrect study intervention; 
• The administration of an incorrect dosage; 

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• The administration of study intervention that has undergone temperature excursion from 
the specified storage range, unless it is determined by the sponsor that the study 
intervention under question is acceptable for use. 
8.4. Treatment of Overdose 
For this study, any dose of investigational product greater than 1 dose within a 24-hour time 
period will be considered an overdose. 
The sponsor does not recommend specific treatment for an overdose. 
In the event of an overdose, the investigator should: 
1. Contact the medical monitor within 24 hours. 
2. Closely monitor the participant for any AEs/SAEs. 
3. Document the quantity of the excess dose as well as the duration of the overdose in 
the CRF. 
4. Overdose is reportable to Safety only when associated with an SAE. 
8.5. Pharmacokinetics 
Pharmacokinetic parameters are not evaluated in this study. 
8.6. Pharmacodynamics 
Pharmacodynamic parameters are not evaluated in this study. 
8.7. Genetics 
Genetics (specified analyses) are not evaluated in this study. 
8.8. Biomarkers 
Biomarkers are not evaluated in this study. 
8.9. Immunogenicity Assessments 
Please refer to Section 8.1. 
8.10. Health Economics 
Health economics/medical resource utilization and health economics parameters are not 
evaluated in this study. 

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8.11. Study Procedures 
If, because of a medical situation (such as disease outbreak or pandemic), study visits cannot 
be conducted in person at the study site, visit procedures should be conducted remotely or via 
telephone, as is feasible. 
It is anticipated that the procedures below will be conducted in a stepwise manner; ensure 
that procedures listed prior to administration of the vaccine are conducted prior to 
vaccination. 
8.11.1. Visit 1 – Vaccination (Day 1) 
• Obtain written informed consent before performing any study-specific procedures. 
• Assign a participant number using the IRT system. 
• Obtain and record the participant demography (including date of birth, sex, race, and 
ethnicity). The full date of birth will be collected to critically evaluate the immune 
response and safety profile by age. 
• Obtain and record any medical history of clinical significance. 
• Perform physical examination evaluating any clinically significant abnormalities within 
the following body systems: general appearance; skin; head, eyes, ears, nose, and throat; 
heart; lungs; abdomen; musculoskeletal; extremities; neurological; and lymph nodes. 
Abnormal results must be recorded on source documents and the Physical Examination 
page of the CRF. 
• Prior to vaccination, perform a urine pregnancy test for WOCBP and ensure the result is 
negative. 
• Record nonstudy vaccinations and medications as described in Section 6.5.3. 
• Ensure and document that all of the inclusion criteria, none of the exclusion criteria, and 
none of the temporary delay criteria are met. 
• Prior to vaccination, measure vital signs, including weight, height, sitting blood pressure 
and pulse rate, respiratory rate, and temperature (oral). 
• Verify the participant’s understanding of and compliance with the protocol requirements 
for contraception. Instruct the participant to use appropriate contraceptives until 28 days 
after administration of investigational product and document the conversation and the 
participant’s affirmation in the participant’s source document. 

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• A blinded site staff member will use the IRT system to obtain the participant’s 
randomization number. An unblinded site staff member will use the IRT to assign the 
investigational product container number, and will prepare the investigational product 
and deliver it to the investigational product administrator. Please refer to the IP manual 
for further instruction on this process. 
• Prior to vaccination, collect a blood sample of approximately 50 mL for immunogenicity 
assessments. 
• The unblinded administrator administers a 0.5-mL injection of investigational product 
into the deltoid muscle of the left arm and a 0.5-mL injection of investigational product 
into the deltoid muscle of the right arm (see Section 6.1.4). Please refer to the IP manual 
for further instruction on this process. 
• Blinded site staff must observe the participant for at least 30 minutes after investigational 
product administration for any acute reactions. Record any immediate AEs in the 
participant’s source documents, on the AE page of the CRF, and on an SAE form as 
applicable. 
• Issue/activate e-diary device. Ask the participant to complete the e-diary from Day 1 to 
Day 7, with Day 1 being the day of vaccination. 
• Issue the participant a measuring device to measure local reactions and a digital 
thermometer to measure daily temperatures, and provide instructions on their use. 
• Ask the participant to contact the site staff or investigator immediately if she is prompted 
by the e-diary from Day 1 to Day 7 following vaccination to determine if an unscheduled 
visit is required (eg, redness or swelling at the injection site measuring >20 measuring 
device units [>10.0 cm]). Remind participants that study staff may contact them to obtain 
additional information on Grade 3 (or above) events entered into the e-diary. 
• Ask the participant to contact the site staff or investigator if an MAE (eg, emergency 
room) or hospitalization occurs. 
• Provide the participant with a contact card (see Section 10.1.10 for a description of the 
contact card). 
• Record AEs as described in Section 8.3. 
• Complete the participant’s source documents. 
• The investigator or an authorized designee completes the CRF and an unblinded site staff 
member updates the investigational product accountability records. 

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• The investigator or appropriately qualified designee reviews the e-diary data online 
following vaccination to evaluate participant compliance and as part of the ongoing 
safety review. 
8.11.2. Visit 2 – 1-Month Follow-up Visit (28-38 Days After Visit 1) 
• Ensure that the participant continues to be eligible for the study, meets none of the 
participant withdrawal criteria as described in Section 7, and meets none of the blood 
draw temporary delay criteria as described in Section 5.5.1.2. 
• Verify the participant’s understanding of and compliance with the protocol requirements 
for contraception. 
• Collect a blood sample of approximately 50 mL for immunogenicity assessments. 
• Review the participant’s e-diary data and collect the e-diary. Collect stop dates of any 
e-diary events ongoing on the last day that the e-diary was completed and record stop 
dates in the CRF. 
• Record nonstudy vaccinations and concomitant medications as described in Section 6.5.3. 
• Record AEs as described in Section 8.3. 
• Complete the participant’s source documents. 
• The investigator or an authorized designee completes the CRF. 
8.11.3. Visit 3 – 6-Month Telephone Call Follow-up Visit (160-200 Days After Visit 1) 
• Ensure that the participant continues to be eligible for the study and meets none of the 
participant withdrawal criteria as described in Section 7. 
• Record nonstudy vaccinations and concomitant medications as described in Section 6.5.3. 
• Record MAEs and SAEs as described in Section 8.3. 
• Complete the participant’s source documents. 
• The investigator or an authorized designee completes the CRF. 
8.11.4. Unscheduled Visits 
If the participant reports redness or swelling at the injection site measuring >20 measuring 
device units (>10.0 cm), fever ≥102.1°F (≥39.0°C), or severe injection site pain, severe 
nausea/vomiting, severe diarrhea, severe headache, severe fatigue, severe muscle pain, or 
severe joint pain, a telephone contact must occur as soon as possible between the participant 
and the investigator or a medically qualified member of the study site staff to assess if an 

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unscheduled visit is required. A site visit must be scheduled as soon as possible to assess the 
extent of the reaction unless: 
• The participant is unable to attend the unscheduled visit, or 
• The reaction is no longer present at the time of the telephone contact, or 
• The participant recorded an incorrect value in the e-diary (confirmation of an e-diary data 
entry error), or 
• The investigator determined it was not needed. 
This telephone contact will be recorded in the CRF and in the participant’s source 
documentation. 
If the participant is unable to attend the unscheduled visit, any ongoing reactions must be 
assessed at the next scheduled visit (Visit 2 and/or Visit 3). 
The reactions should be assessed by the investigator or a medically qualified member of the 
study staff, such as a study physician or a study nurse, as applicable to the investigator’s local 
practice, who will: 
• Measure oral temperature. 
• Measure minimum and maximum diameters of redness (if present). 
• Measure minimum and maximum diameters of swelling (if present). 
• Assess any injection site pain that is present in accordance with the grading scale 
provided in Section 8.2.2. 
• Assess any systemic events (nausea/vomiting, diarrhea, headache, fatigue, muscle pain, 
or joint pain) that are present in accordance with the grading scale provided in 
Section 8.2.2. 
The investigator or an authorized designee will complete the unscheduled visit page of the 
CRF. 
Participants will also be instructed to contact site staff if they experience any possible 
Grade 4 prompted systemic event (ie, emergency room visit or hospitalization for 
nausea/vomiting, diarrhea, headache, fatigue, muscle pain, or joint pain) within 7 days after 
vaccination. Study staff may contact the participant to obtain additional information on 
Grade 3 events entered into the e-diary. Lastly, participants will be instructed to contact the 
site to report any significant illness, medical event, or hospitalization that occurs during the 
study period. The site should determine if an unscheduled visit to further evaluate the event 
is warranted in all such cases. 

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9. STATISTICAL CONSIDERATIONS 
Methodology for summary and statistical analyses of the data collected in this study is 
described here and further detailed in a SAP, which will be maintained by the sponsor. The 
SAP may modify what is outlined in the protocol where appropriate; however, any major 
modifications of the primary endpoint definitions or their analyses will also be reflected in a 
protocol amendment. 
9.1. Estimands and Statistical Hypotheses 
9.1.1. Statistical Hypotheses 
There are no statistical hypotheses defined in the study. 
9.1.2. Estimands 
Primary (Safety): 
In participants receiving at least 1 dose of the investigational product: 
• The proportion of participants reporting prompted local reactions within 7 days following 
investigational product administration. 
• The proportion of participants reporting prompted systemic events within 7 days 
following investigational product administration. 
• The proportion of participants reporting AEs through 1 month following investigational 
product administration. 
• The proportion of participants reporting MAEs and SAEs through 6 months following 
investigational product administration. 
Missing e-diary data will not be imputed; missing AE dates and missing AE severity will be 
handled according to Pfizer safety rules. 
Primary (Immunogenicity): 
In participants receiving all doses of the investigational products and in compliance with the 
key protocol criteria (evaluable participants): 
• The difference in proportions of participants with anti–tetanus toxoid antibody 
concentrations ≥0.1 IU/mL measured 1 month after vaccination between the GBS6+Tdap 
group and the placebo+Tdap group. 
• The difference in proportions of participants with anti–diphtheria toxoid antibody 
concentrations ≥0.1 IU/mL measured 1 month after vaccination between the GBS6+Tdap 
group and the placebo+Tdap group. 

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• GMR, estimated by the GMR of anti–pertussis toxin antibodies from the GBS6+Tdap 
group to the placebo+Tdap group measured 1 month after vaccination. 
• GMR, estimated by the GMR of anti–filamentous hemagglutinin 
(anti-FHA) antibodies from the GBS6+Tdap group to the placebo+Tdap group measured 
1 month after vaccination. 
• GMR, estimated by the GMR of antipertactin (anti-PRN) antibodies from the 
GBS6+Tdap group to the placebo+Tdap group measured 1 month after vaccination. 
• GBS capsular polysaccharide (CPS) serotype-specific IgG GMR, estimated by the GMR 
of GBS CPS serotype-specific IgG antibodies from the GBS6+Tdap group to the 
GBS6+placebo group measured 1 month after vaccination. 
These estimands estimate the vaccine effect in the hypothetical setting where participants 
follow the study schedules and protocol requirements as directed. Missing serology results 
will not be imputed, as missing completely at random (MCAR) is assumed. For participants 
who discontinue from the study or have major protocol violations, all postdiscontinuation or 
violation observations will be censored. 
Secondary 
Not applicable. 
Exploratory 
In participants receiving all doses of the investigational products and in compliance with the 
key protocol criteria (evaluable participants): 
• Proportions of participants with anti–tetanus toxoid and anti–diphtheria toxoid antibody 
concentrations ≥0.1 IU/mL measured before vaccination and 1 month after vaccination 
for both the GBS6+Tdap group and the placebo+Tdap group. 
• Proportions of participants with anti–tetanus toxoid and anti–diphtheria toxoid antibody 
concentrations ≥1.0 IU/mL measured before vaccination and 1 month after vaccination 
for both the GBS6+Tdap group and the placebo+Tdap group. 
• The differences in proportions of participants with anti–tetanus toxoid and 
anti–diphtheria toxoid antibody concentrations ≥0.1 IU/mL measured 1 month after 
vaccination between the GBS6+Tdap group and the placebo+Tdap group. 
• Geometric mean concentrations (GMCs) of anti–tetanus toxoid, anti–diphtheria toxoid, 
and anti–pertussis component (pertussis toxin, FHA, PRN, and FIM) antibodies measured 
before vaccination and 1 month after vaccination for both the GBS6+Tdap group and the 
placebo+Tdap group. 

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• Geometric mean fold rises (GMFRs) of anti–tetanus toxoid, anti–diphtheria toxoid, and 
anti–pertussis component (pertussis toxin, FHA, PRN, and FIM) antibodies measured 
from before vaccination to 1 month after vaccination for both the GBS6+Tdap group and 
the placebo+Tdap group. 
• GBS capsular polysaccharide (CPS) serotype-specific IgG GMCs measured before and 
1 month after vaccination for both the GBS6+Tdap group and the GBS6+placebo group. 
• GBS capsular polysaccharide (CPS) serotype-specific IgG GMFRs measured from before 
vaccination to 1 month after vaccination for both GBS6+Tdap group and GBS6+placebo 
group. 
9.2. Sample Size Determination 
The study sample sizes are not based on any formal statistical hypothesis test considerations. 
The study aims to have a sufficient number of participants in order to describe the safety and 
immunogenicity of concomitantly administered Tdap and GBS6. With approximately 
100 participants to be enrolled in each group, the lower bound of the 2-sided 95% CI for the 
IgG GMR, estimated by the GMR of GBS CPS serotype-specific IgG antibodies from the 
GBS6+Tdap group to the GBS6+placebo group measured 1 month after vaccination, is 
approximately 0.40, 0.38, 0.53, 0.48, 0.63, and 0.46, assuming that there was no inherent 
difference between these 2 groups, and the maximum SD (natural logarithm scale) is 3.09, 
3.27, 2.15, 2.48, 1.58, and 2.65 for serotypes Ia, Ib, II, III, IV, and V, respectively, from 
Study C1091001, with a 10% nonevaluable rate. 
With a similar assumption of no inherent difference between groups, a similar nonevaluable 
rate, and 100 enrolled participants in each group, the lower bound of the 2-sided 95% CI for 
the GMR, estimated by the GMR of anti–pertussis toxin antibodies, anti-FHA antibodies, or 
anti-PRN antibodies from the GBS6+Tdap group to the placebo+Tdap group measured 
1 month after vaccination, is approximately 0.74, 0.78, and 0.72, assuming maximum SDs 
(natural logarithm scale) of 1.01, 0.85, and 1.12 for anti–pertussis toxin antibody, anti-FHA 
antibody, anti-PRN antibody endpoints, respectively, and the lower bound of the 2-sided 
95% CI for the difference in proportions of participants with anti–tetanus toxoid antibody 
concentrations ≥0.1 IU/mL and participants with anti–diphtheria toxoid antibody 
concentrations ≥0.1 IU/mL measured 1 month after vaccination between the GBS6+Tdap 
group and the placebo+Tdap group is approximately -0.05 and -0.076, respectively, assuming 
that the proportions are 0.99 and 0.94 for anti–tetanus toxoid antibody and anti–diphtheria 
toxoid antibody endpoints from Study B1971015. 
The primary safety objective includes the endpoints for local reactions, systemic events, AEs, 
MAEs, and SAEs. 
Table 4 shows the probability of detecting at least 1 event (local reactions, systemic events, 
AEs, MAEs, or SAEs). The number of participants in each study group is 100, which 
provides a 86% chance of observing at least 1 event in a group, assuming a true rate of at 
least 2%. 

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Table 4. 
Probability of Observing at Least 1 Event by Assumed True Event Rates 
 
Assumed True Event Percentage 
Probability 
0.10% 
9.52% 
0.50% 
39.4% 
1.0% 
63.4% 
2.0% 
86.7% 
3.0% 
95.2% 
4.0% 
98.3% 
5.0% 
99.4% 
 
9.3. Analysis Sets 
For purposes of analysis, the following analysis sets are defined: 
 
Population 
Description 
Enrolled 
All participants who sign the ICD. 
Randomly assigned to 
investigational product 
All participants who are assigned a randomization number in 
the IWR system. 
Evaluable 
All participants who are eligible, receive all doses of the 
investigational products to which they were randomized, 
have blood drawn for assay testing within the specified time 
frame for 1 month after vaccination, have at least 1 valid and 
determinate assay result at the 1-month postvaccination visit, 
and have no major protocol violations. 
Modified intent-to-treat 
(mITT) 
All randomized participants who receive at least 1 dose of the 
investigational products and have at least 1 valid and 
determinate assay result after vaccination. 
Safety 
All participants who receive at least 1 dose of the 
investigational products and have at least 1 valid postdose 
assessment. 
 
9.4. Statistical Analyses 
The SAP will be developed and finalized before any analyses are performed and will 
describe the analyses and procedures for accounting for missing, unused, and spurious data. 
This section is a summary of the planned statistical analyses of the primary and secondary 
endpoints. 
9.4.1. Safety Analyses 
All safety analyses will be performed on the safety population. 

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Endpoint 
Statistical Analysis Methods 
Primary 
• Point estimates and exact 2-sided 95% CIs will be calculated using the 
Clopper-Pearson method for the proportion of participants reporting each 
event (local reactions, systemic events, AEs, MAEs, and SAEs) for each 
vaccine group. 
• AEs and SAEs will be categorized according to MedDRA terms. A 
3-tiered approach will be used to summarize AEs. For both Tier 1 and 
Tier 2 events, the 95% CIs for the difference in the proportion of 
participants reporting events between the GBS6+Tdap group and the 
GBS6+placebo group, and between the GBS6+Tdap group and the 
placebo+Tdap group, will be calculated using the test statistic proposed 
by Miettinen and Nurminen. In addition, for Tier 1 events (if any), the 
asymptotic p-values will also be presented for the difference in the 
proportion of participants reporting events based on the same test statistic 
and under the assumption that the test statistic is asymptotically normally 
distributed. There are no preidentified Tier 1 events for this study. A 
MedDRA preferred term is defined as a Tier 2 event if there are 1% of 
participants in at least 1 vaccine group reporting the event. Descriptive 
summary statistics (counts and proportions) will be provided for Tier 3 
events for each vaccine group. 
The safety analyses are based on the safety population. Participants will 
be summarized according to the vaccine group corresponding to the 
investigational product they actually received. Missing e-diary data will 
not be imputed; missing AE dates and missing AE severity will be 
addressed using the Pfizer safety rules. 
Secondary 
• N/A 
Exploratory 
• N/A 
 
9.4.2. Immunogenicity Analyses 
 
Endpoint 
Statistical Analysis Methods 
Primary 
• The differences (GBS6+Tdap group minus placebo+Tdap group) in 
proportions of participants with anti–tetanus toxoid and anti–diphtheria 
toxoid antibody concentrations ≥0.1 IU/mL at 1 month after vaccination 
will be calculated, and associated 2-sided 95% CIs will be calculated 
using the Miettinen and Nurminen method 
• GMRs of the GBS6+Tdap group to the placebo+Tdap group for the 
anti–pertussis toxin, anti-FHA, and anti-PRN antibody concentrations at 
1 month after vaccination will be calculated, along with associated 
2-sided 95% CIs. The GMR will be calculated as the group mean 
difference of logarithmically transformed antibody levels and 
transformed back to the original units. Two (2)-sided 95% CIs will also 
be obtained by calculating CIs using Student’s t distribution for the mean 

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Endpoint 
Statistical Analysis Methods 
difference of measures on the logarithmically transformed assay results 
and transforming confidence limits back to the original units. 
• GBS6 serotype-specific IgG GMR of the GBS6+placebo group to the 
GBS6+Tdap group at 1 month after vaccination will be calculated, along 
with associated 2-sided 95% CIs, using the same method as for 
anti–pertussis toxin, anti-FHA, and anti-PRN antibody GMRs. 
CCI 
This analysis is based on the evaluable population. An additional analysis 
will be performed based on the mITT population if there is enough 
difference between the mITT population and the evaluable population. 
Participants will be summarized according to the vaccine group to which 
they were randomized. Missing serology data will not be imputed. 
Exploratory 
• Point estimates and the exact 2-sided 95% CIs will be calculated using 
the Clopper-Pearson method for the proportion of participants with 
anti–tetanus toxoid and anti–diphtheria toxoid antibody concentrations 
≥0.1 IU/mL at each available time point for the GBS6+Tdap and 
placebo+Tdap groups. 
• Point estimates and the exact 2-sided 95% CIs will be calculated using 
the Clopper-Pearson method for the proportion of participants with 
anti–tetanus toxoid and anti–diphtheria toxoid antibody concentrations 
≥1.0 IU/mL at each available time point for the GBS6+Tdap and 
placebo+Tdap groups. 
• The differences (GBS6+Tdap group minus placebo+Tdap group) in 
proportions of participants with anti–tetanus toxoid and anti–diphtheria 
toxoid antibody concentrations ≥1.0 IU/mL measured at each available 
time point after vaccination will be calculated and associated 2-sided 
95% CIs will be calculated using the Miettinen and Nurminen method. 
• Geometric mean concentrations (GMCs) of anti-TTd, anti-DTd, 
anti–pertussis toxin, anti-FHA, anti-PRN, and anti-FIM antibodies at 
each available time point will be descriptively summarized for the 
GBS6+Tdap and placebo+Tdap groups, along with associated 2-sided 
95% CIs. The GMC will be calculated as the mean of the antibody titers 
after the logarithm transformation and then transformed back to its 
original scale. Two (2)-sided 95% CIs will be constructed by calculating 
a CI for the mean of the logarithmically transformed assay results 
computed based on Student’s t distribution and transforming confidence 
limits back to the original units. 

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Endpoint 
Statistical Analysis Methods 
• Geometric mean fold rises (GMFRs) from before vaccination to each 
available time point after vaccination will be provided for anti-TTd, 
anti-DTd, anti–pertussis toxin, anti-FHA, anti-PRN, and anti-FIM 
antibodies for both the GBS6+Tdap and placebo+Tdap groups, along 
with associated 2-sided 95% CIs. The GMFR will be calculated as the 
mean of the difference of logarithmically transformed antibody titers 
(postvaccination minus prevaccination for each participant) and 
transformed back to the original units. Two (2)-sided 95% CIs will be 
computed by calculating CIs for the mean difference of measures on the 
logarithmically transformed assay results using Student’s t distribution 
and transforming back to the original units. 
• GBS capsular polysaccharide (CPS) serotype-specific IgG GMCs at each 
available time point will be descriptively summarized for the 
GBS6+Tdap and GBS6+placebo groups, along with associated 2-sided 
95% CIs, using the same method as for anti-TTd, anti-DTd, anti– 
pertussis toxin, anti-FHA, anti-PRN, and anti-FIM antibody GMCs. 
• GBS capsular polysaccharide (CPS) serotype-specific IgG GMFRs from 
before vaccination to each available time point after vaccination will be 
provided, for both the GBS6+Tdap and GBS6+placebo groups, along 
with associated 2-sided 95% CIs using the same method as for anti-TTd, 
anti-DTd, anti–pertussis toxin, anti-FHA, anti-PRN, and anti-FIM 
antibody GMFRs. 
• GBS capsular polysaccharide (CPS) serotype-specific empirical RCDCs 
for IgG antibody concentrations at each available postvaccination time 
point will be presented, for both the GBS6+Tdap and GBS6+placebo 
groups. 
• Point estimates and the exact 2-sided 95% CIs will be calculated using 
the Clopper-Pearson method for the proportions of participants with 
serotype-specific GBS-positive vaginal/rectal cultures at each available 
time point for all 3 groups. 
IgG antibody concentrations denoted as BLQ will be imputed as 0.5 × LLOQ 
for GMC and GMT analyses, respectively. 
The above analyses are based on the evaluable population. An additional 
analysis will be performed based on the mITT population if there is enough 
difference between the mITT population and the evaluable population. 
Participants will be summarized according to the vaccine group to which 
they were randomized. Missing serology data will not be imputed. 

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9.5. Interim Analyses 
There will be 1 planned interim analysis when Visit 2 (1-month postvaccination visit) safety 
and immunogenicity data from all participants are available. 
9.6. Data Monitoring Committee or Other Independent Oversight Committee 
This study will use an established E-DMC. The E-DMC is independent of the study team 
and includes only external members. The E-DMC charter describes the role of the E-DMC 
in more detail. 
The E-DMC will be responsible for ongoing monitoring of the safety of participants in the 
study according to the charter. The recommendations made by the E-DMC to alter the 
conduct of the study will be forwarded to the appropriate Pfizer personnel for final decision. 
Pfizer will forward such decisions, which may include summaries of aggregate analyses of 
safety data, to regulatory authorities, as appropriate. 

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10. SUPPORTING DOCUMENTATION AND OPERATIONAL CONSIDERATIONS 
10.1. Appendix 1: Regulatory, Ethical, and Study Oversight Considerations 
10.1.1. Regulatory and Ethical Considerations 
This study will be conducted in accordance with the protocol and with the following: 
• Consensus ethical principles derived from international guidelines including the 
Declaration of Helsinki and CIOMS International Ethical Guidelines; 
• Applicable ICH GCP guidelines; 
• Applicable laws and regulations, including applicable privacy laws. 
The protocol, protocol amendments, ICD, SRSD(s), and other relevant documents 
(eg, advertisements) must be reviewed and approved by the sponsor and submitted to an 
IRB/EC by the investigator and reviewed and approved by the IRB/EC before the study is 
initiated. 
Any amendments to the protocol will require IRB/EC approval before implementation of 
changes made to the study design, except for changes necessary to eliminate an immediate 
hazard to study participants. 
The investigator will be responsible for the following: 
• Providing written summaries of the status of the study to the IRB/EC annually or 
more frequently in accordance with the requirements, policies, and procedures 
established by the IRB/EC; 
• Notifying the IRB/EC of SAEs or other significant safety findings as required by 
IRB/EC procedures; 
• Providing oversight of the conduct of the study at the site and adherence to 
requirements of 21 CFR, ICH guidelines, the IRB/EC, European regulation 536/2014 
for clinical studies (if applicable), and all other applicable local regulations. 
10.1.1.1. Reporting of Safety Issues and Serious Breaches of the Protocol or ICH GCP 
In the event of any prohibition or restriction imposed (ie, clinical hold) by an applicable 
regulatory authority in any area of the world, or if the investigator is aware of any new 
information that might influence the evaluation of the benefits and risks of the study 
intervention, Pfizer should be informed immediately. 
In addition, the investigator will inform Pfizer immediately of any urgent safety measures 
taken by the investigator to protect the study participants against any immediate hazard, and 
of any serious breaches of this protocol or of ICH GCP that the investigator becomes aware 
of. 

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10.1.2. Financial Disclosure 
Investigators and subinvestigators will provide the sponsor with sufficient, accurate financial 
information as requested to allow the sponsor to submit complete and accurate financial 
certification or disclosure statements to the appropriate regulatory authorities. Investigators 
are responsible for providing information on financial interests during the course of the study 
and for 1 year after completion of the study. 
10.1.3. Informed Consent Process 
The investigator or his/her representative will explain the nature of the study, including the 
risks and benefits, to the participant and answer all questions regarding the study. The 
participant should be given sufficient time and opportunity to ask questions and to decide 
whether or not to participate in the trial. 
Participants must be informed that their participation is voluntary. Participants will be 
required to sign a statement of informed consent that meets the requirements of 21 CFR 50, 
local regulations, ICH guidelines, HIPAA requirements, where applicable, and the IRB/EC 
or study center. 
The investigator must ensure that each study participant is fully informed about the nature 
and objectives of the study, the sharing of data related to the study, and possible risks 
associated with participation, including the risks associated with the processing of the 
participant’s personal data. 
The participant must be informed that her personal study-related data will be used by the 
sponsor in accordance with local data protection law. The level of disclosure must also be 
explained to the participant. 
The participant must be informed that her medical records may be examined by Clinical 
Quality Assurance auditors or other authorized personnel appointed by the sponsor, by 
appropriate IRB/EC members, and by inspectors from regulatory authorities. 
The investigator further must ensure that each study participant is fully informed about her 
right to access and correct her personal data and to withdraw consent for the processing of 
her personal data. 
The medical record must include a statement that written informed consent was obtained 
before the participant was enrolled in the study and the date the written consent was obtained. 
The authorized person obtaining the informed consent must also sign the ICD. 
Participants must be reconsented to the most current version of the ICD(s) during their 
participation in the study. 
A copy of the ICD(s) must be provided to the participant. 
Participants who are rescreened are required to sign a new ICD. 

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10.1.4. Data Protection 
All parties will comply with all applicable laws, including laws regarding the implementation 
of organizational and technical measures to ensure protection of participant data. 
Participants’ personal data will be stored at the study site in encrypted electronic and/or paper 
form and will be password-protected or secured in a locked room to ensure that only 
authorized study staff have access. The study site will implement appropriate technical and 
organizational measures to ensure that the personal data can be recovered in the event of 
disaster. In the event of a potential personal data breach, the study site will be responsible 
for determining whether a personal data breach has in fact occurred and, if so, providing 
breach notifications as required by law. 
To protect the rights and freedoms of participants with regard to the processing of personal 
data, participants will be assigned a single, participant-specific numerical code. Any 
participant records or data sets that are transferred to the sponsor will contain the numerical 
code; participant names will not be transferred. All other identifiable data transferred to the 
sponsor will be identified by this single, participant-specific code. The study site will 
maintain a confidential list of participants who participated in the study, linking each 
participant’s numerical code to her actual identity and medical record identification. In case 
of data transfer, the sponsor will protect the confidentiality of participants’ personal data 
consistent with the clinical study agreement and applicable privacy laws. 
10.1.5. Dissemination of Clinical Study Data 
Pfizer fulfills its commitment to publicly disclose clinical study results through posting the 
results of studies on www.clinicaltrials.gov (ClinicalTrials.gov), the EudraCT, and/or 
www.pfizer.com, and other public registries in accordance with applicable local 
laws/regulations. In addition, Pfizer reports study results outside of the requirements of local 
laws/regulations pursuant to its SOPs. 
In all cases, study results are reported by Pfizer in an objective, accurate, balanced, and 
complete manner and are reported regardless of the outcome of the study or the country in 
which the study was conducted. 
www.clinicaltrials.gov 
Pfizer posts clinical trial results on www.clinicaltrials.gov for Pfizer-sponsored interventional 
studies (conducted in patients) that evaluate the safety and/or efficacy of a product, 
regardless of the geographical location in which the study is conducted. These results are 
submitted for posting in accordance with the format and timelines set forth by US law. 
EudraCT 
Pfizer posts clinical trial results on EudraCT for Pfizer-sponsored interventional studies in 
accordance with the format and timelines set forth by EU requirements. 

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www.pfizer.com 
Pfizer posts public disclosure synopses (CSR synopses in which any data that could be used 
to identify individual participants have been removed) on www.pfizer.com for 
Pfizer-sponsored interventional studies at the same time the corresponding study results are 
posted to www.clinicaltrials.gov. 
Documents within marketing authorization packages/submissions 
Pfizer complies with the European Union Policy 0070, the proactive publication of clinical 
data to the EMA website. Clinical data, under Phase 1 of this policy, includes clinical 
overviews, clinical summaries, CSRs, and appendices containing the protocol and protocol 
amendments, sample CRFs, and statistical methods. Clinical data, under Phase 2 of this 
policy, includes the publishing of individual participant data. Policy 0070 applies to new 
marketing authorization applications submitted via the centralized procedure since 
01 January 2015 and applications for line extensions and for new indications submitted via 
the centralized procedure since 01 July 2015. 
Data Sharing 
Pfizer provides researchers secure access to patient-level data or full CSRs for the purposes 
of “bona-fide scientific research” that contributes to the scientific understanding of the 
disease, target, or compound class. Pfizer will make available data from these trials 
24 months after study completion. Patient-level data will be anonymized in accordance with 
applicable privacy laws and regulations. CSRs will have personally identifiable information 
redacted. 
Data requests are considered from qualified researchers with the appropriate competencies to 
perform the proposed analyses. Research teams must include a biostatistician. Data will not 
be provided to applicants with significant conflicts of interest, including individuals 
requesting access for commercial/competitive or legal purposes. 
10.1.6. Data Quality Assurance 
All participant data relating to the study will be recorded on printed or electronic CRF unless 
transmitted to the sponsor or designee electronically (eg, laboratory data). The investigator is 
responsible for verifying that data entries are accurate and correct by physically or 
electronically signing the CRF. 
The investigator must maintain accurate documentation (source data) that supports the 
information entered in the CRF. 
The investigator must ensure that the CRFs are securely stored at the study site in encrypted 
electronic and/or paper form and are password-protected or secured in a locked room to 
prevent access by unauthorized third parties. 

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The investigator must permit study-related monitoring, audits, IRB/EC review, and 
regulatory agency inspections and provide direct access to source data documents. This 
verification may also occur after study completion. It is important that the investigator(s) 
and their relevant personnel are available during the monitoring visits and possible audits or 
inspections and that sufficient time is devoted to the process. 
Monitoring details describing strategy (eg, risk-based initiatives in operations and quality, 
such as risk management and mitigation strategies and analytical risk-based monitoring), 
methods, responsibilities, and requirements, including handling of noncompliance issues and 
monitoring techniques (central, remote, or on-site monitoring), are provided in the 
monitoring plan. 
The sponsor or designee is responsible for the data management of this study, including 
quality checking of the data. 
Study monitors will perform ongoing source data verification to confirm that data entered 
into the CRF by authorized site personnel are accurate, complete, and verifiable from source 
documents; that the safety and rights of participants are being protected; and that the study is 
being conducted in accordance with the currently approved protocol and any other study 
agreements, ICH GCP, and all applicable regulatory requirements. 
Records and documents, including signed ICDs, pertaining to the conduct of this study must 
be retained by the investigator for 15 years after study completion unless local regulations or 
institutional policies require a longer retention period. No records may be destroyed during 
the retention period without the written approval of the sponsor. No records may be 
transferred to another location or party without written notification to the sponsor. The 
investigator must ensure that the records continue to be stored securely for as long as they are 
maintained. 
When participant data are to be deleted, the investigator will ensure that all copies of such 
data are promptly and irrevocably deleted from all systems. 
The investigator(s) will notify the sponsor or its agents immediately of any regulatory 
inspection notification in relation to the study. Furthermore, the investigator will cooperate 
with the sponsor or its agents to prepare the investigator site for the inspection and will allow 
the sponsor or its agent, whenever feasible, to be present during the inspection. The 
investigator site and investigator will promptly resolve any discrepancies that are identified 
between the study data and the participant's medical records. The investigator will promptly 
provide copies of the inspection findings to the sponsor or its agent. Before response 
submission to the regulatory authorities, the investigator will provide the sponsor or its 
agents with an opportunity to review and comment on responses to any such findings. 
10.1.7. Source Documents 
Source documents provide evidence for the existence of the participant and substantiate the 
integrity of the data collected. Source documents are filed at the investigator site. 

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Data reported on the CRF or entered in the eCRF that are from source documents must be 
consistent with the source documents or the discrepancies must be explained. The 
investigator may need to request previous medical records or transfer records, depending on 
the study. Also, current medical records must be available. 
The definition of what constitutes source data can be found in ISF, which is maintained by 
the sponsor. 
Description of the use of computerized systems is documented in the data management plan, 
which is maintained by the sponsor. 
The investigator must maintain accurate documentation (source data) that supports the 
information entered in the CRF. 
Study monitors will perform ongoing source data verification to confirm that data entered 
into the CRF by authorized site personnel are accurate, complete, and verifiable from source 
documents; that the safety and rights of participants are being protected; and that the study is 
being conducted in accordance with the currently approved protocol and any other study 
agreements, ICH GCP guidelines, and all applicable regulatory requirements. 
10.1.8. Study and Site Start and Closure 
The study start date is the date on which the clinical study will be open for recruitment of 
participants. 
The first act of recruitment is the date of the first participant’s first visit and will be the study 
start date. 
The sponsor designee reserves the right to close the study site or terminate the study at any 
time for any reason at the sole discretion of the sponsor. Study sites will be closed upon 
study completion. A study site is considered closed when all required documents and study 
supplies have been collected and a study-site closure visit has been performed. 
The investigator may initiate study-site closure at any time upon notification to the CRO if 
requested to do so by the responsible IRB/EC or if such termination is required to protect the 
health of study participants. 
Reasons for the early closure of a study site by the sponsor may include but are not limited 
to: 
• Failure of the investigator to comply with the protocol, the requirements of the 
IRB/EC or local health authorities, the sponsor's procedures, or GCP guidelines; 
• Inadequate recruitment of participants by the investigator; 
• Discontinuation of further study intervention development. 

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If the study is prematurely terminated or suspended, the sponsor shall promptly inform the 
investigators, the ECs/IRBs, the regulatory authorities, and any CRO(s) used in the study of 
the reason for termination or suspension, as specified by the applicable regulatory 
requirements. The investigator shall promptly inform the participant and should assure 
appropriate participant therapy and/or follow-up. 
Study termination is also provided for in the clinical study agreement. If there is any conflict 
between the contract and this protocol, the contract will control as to termination rights. 
10.1.9. Publication Policy 
The results of this study may be published or presented at scientific meetings by the 
investigator after publication of the overall study results or 1 year after the end of the study 
(or study termination), whichever comes first. 
The investigator agrees to refer to the primary publication in any subsequent publications, 
such as secondary manuscripts, and submits all manuscripts or abstracts to the sponsor 
30 days before submission. This allows the sponsor to protect proprietary information and to 
provide comments, and the investigator will, on request, remove any previously undisclosed 
confidential information before disclosure, except for any study- or Pfizer 
intervention-related information necessary for the appropriate scientific presentation or 
understanding of the study results. 
For all publications relating to the study, the investigator will comply with recognized ethical 
standards concerning publications and authorship, including those established by the 
International Committee of Medical Journal Editors. 
The sponsor will comply with the requirements for publication of the overall study results 
covering all investigator sites. In accordance with standard editorial and ethical practice, the 
sponsor will support publication of multicenter studies only in their entirety and not as 
individual site data. In this case, a coordinating investigator will be designated by mutual 
agreement. 
Authorship of publications for the overall study results will be determined by mutual 
agreement and in line with International Committee of Medical Journal Editors authorship 
requirements. 
If publication is addressed in the clinical study agreement, the publication policy set out in 
this section will not apply. 

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10.1.10. Sponsor’s Qualified Medical Personnel 
The contact information for the sponsor's appropriately qualified medical personnel for the 
study is documented in the study contact list located in the ISF. 
To facilitate access to appropriately qualified medical personnel on study-related medical 
questions or problems, participants are provided with an emergency contact card (ECC) at 
the time of informed consent. The ECC contains, at a minimum, (a) protocol and study 
intervention identifiers, (b) participant’s study identification number, (c) site emergency 
phone number active 24 hours/day, 7 days per week, and (d) Pfizer Call Center number. 
The contact number can also be used by investigator staff if they are seeking advice on 
medical questions or problems; however, it should be used only in the event that the 
established communication pathways between the investigator site and the study team are not 
available. 
The ECC is intended to augment, but not replace, the established communication pathways 
between the investigator, site staff, and the study team. The ECC is to be used by healthcare 
professionals not involved in the research study, only as a means of reaching the investigator 
or site staff related to the care of a participant. The Pfizer Call Center number should only be 
used when the investigator and site staff cannot be reached. The Pfizer Call Center number 
is not intended for use by the participant directly; if a participant calls that number directly, 
she will be directed back to the investigator site. 
10.2. Appendix 2: Clinical Laboratory Tests 
Not applicable. 

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10.3. Appendix 3: Adverse Events: Definitions and Procedures for Recording, 
Evaluating, Follow-up, and Reporting 
10.3.1. Definition of AE 
 
AE Definition 
• An AE is any untoward medical occurrence in a patient or clinical study 
participant, temporally associated with the use of study intervention, whether or not 
considered related to the study intervention. 
• Note: An AE can therefore be any unfavorable and unintended sign (including an 
abnormal laboratory finding), symptom, or disease (new or exacerbated) 
temporally associated with the use of study intervention. 
 
 
Events Meeting the AE Definition 
• Any abnormal laboratory test results (hematology, clinical chemistry, or urinalysis) 
or other safety assessments (eg, ECG, radiological scans, vital sign measurements), 
including those that worsen from baseline, considered clinically significant in the 
medical and scientific judgment of the investigator. Any abnormal laboratory test 
results that meet any of the conditions below must be recorded as an AE: 
• Is associated with accompanying symptoms. 
• Requires additional diagnostic testing or medical/surgical intervention. 
• Leads to a change in study dosing (outside of any protocol-specified dose 
adjustments) or discontinuation from the study, significant additional 
concomitant drug treatment, or other therapy. 
• Exacerbation of a chronic or intermittent preexisting condition, including either an 
increase in frequency and/or intensity of the condition. 
• New conditions detected or diagnosed after study intervention administration, even 
though it may have been present before the start of the study. 
• Signs, symptoms, or the clinical sequelae of a suspected drug-drug interaction. 
• Signs, symptoms, or the clinical sequelae of a suspected overdose of either study 
intervention or a concomitant medication. Overdose per se will not be reported as 
an AE/SAE unless it is an intentional overdose taken with possible 
suicidal/self-harming intent. Such overdoses should be reported regardless of 
sequelae. 

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Events NOT Meeting the AE Definition 
• Any clinically significant abnormal laboratory findings or other abnormal safety 
assessments which are associated with the underlying disease, unless judged by the 
investigator to be more severe than expected for the participant’s condition. 
• The disease/disorder being studied or expected progression, signs, or symptoms of 
the disease/disorder being studied, unless more severe than expected for the 
participant’s condition. 
• Medical or surgical procedure (eg, endoscopy, appendectomy): the condition that 
leads to the procedure is the AE. 
• Situations in which an untoward medical occurrence did not occur (social and/or 
convenience admission to a hospital). 
• Anticipated day-to-day fluctuations of preexisting disease(s) or condition(s) present 
or detected at the start of the study that do not worsen. 
 
10.3.2. Definition of an SAE 
If an event is not an AE per definition above, then it cannot be an SAE even if serious 
conditions are met (eg, hospitalization for signs/symptoms of the disease under study, death 
due to progression of disease). 
 
An SAE is defined as any untoward medical occurrence that, at any dose: 
a.  Results in death 
b. Is life-threatening 
The term “life-threatening” in the definition of “serious” refers to an event in which the 
participant was at risk of death at the time of the event. It does not refer to an event that 
hypothetically might have caused death if it were more severe. 
c.  Requires inpatient hospitalization or prolongation of existing hospitalization 
In general, hospitalization signifies that the participant has been detained (usually 
involving at least an overnight stay) at the hospital or emergency ward for observation 
and/or treatment that would not have been appropriate in the physician’s office or 
outpatient setting. Complications that occur during hospitalization are AEs. If a 
complication prolongs hospitalization or fulfills any other serious criteria, the event is 
serious. When in doubt as to whether “hospitalization” occurred or was necessary, the AE 
should be considered serious. 

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An SAE is defined as any untoward medical occurrence that, at any dose: 
Hospitalization for elective treatment of a preexisting condition that did not worsen from 
baseline is not considered an AE. 
d. Results in persistent disability/incapacity 
• The term disability means a substantial disruption of a person’s ability to conduct 
normal life functions. 
• This definition is not intended to include experiences of relatively minor medical 
significance, such as uncomplicated headache, nausea, vomiting, diarrhea, 
influenza, and accidental trauma (eg, sprained ankle) which may interfere with or 
prevent everyday life functions but do not constitute a substantial disruption. 
e.  Is a congenital anomaly/birth defect 
f. Is a suspected transmission via a Pfizer product of an infectious agent, pathogenic 
or nonpathogenic, is considered serious 
• The event may be suspected from clinical symptoms or laboratory findings 
indicating an infection in a participant exposed to a Pfizer product. The terms 
“suspected transmission” and “transmission” are considered synonymous. These 
cases are considered unexpected and handled as serious expedited cases by 
pharmacovigilance personnel. Such cases are also considered for reporting as 
product defects, if appropriate. 
g. Other situations: 
• Medical or scientific judgment should be exercised in deciding whether SAE 
reporting is appropriate in other situations, such as important medical events that 
may not be immediately life-threatening or result in death or hospitalization but 
may jeopardize the participant or may require medical or surgical intervention to 
prevent one of the other outcomes listed in the above definition. These events 
should usually be considered serious. 
• 
Examples of such events include invasive or malignant cancers, intensive treatment 
in an emergency room or at home for allergic bronchospasm, blood dyscrasias or 
convulsions that do not result in hospitalization, or development of drug 
dependency or drug abuse. 
 
10.3.3. Definition of Medically Attended Adverse Event 
An MAE is defined as a nonserious AE that results in an evaluation at a medical facility. 

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10.3.4. Definition of Immediate Adverse Event 
Immediate AEs, defined as AEs occurring within the first 30 minutes after study intervention 
administration. 
10.3.5. Recording/Reporting and Follow-up of AEs and/or SAEs 
AE and SAE Recording/Reporting 
The table below summarizes the requirements for recording adverse events on the CRF 
and for reporting serious adverse events on the Vaccine SAE Reporting Form to Pfizer 
Safety. These requirements are delineated for 3 types of events: (1) SAEs; (2) nonserious 
adverse events (AEs); and (3) exposure to the study intervention under study during 
pregnancy or breastfeeding, and occupational exposure. 
It should be noted that the Vaccine SAE Reporting Form for reporting of SAE information 
is not the same as the AE page of the CRF. When the same data are collected, the forms 
must be completed in a consistent manner. AEs should be recorded using concise medical 
terminology and the same AE term should be used on both the CRF and the Vaccine SAE 
Reporting Form for reporting of SAE information. 
 
Safety Event 
Recorded on the CRF 
Reported on the Vaccine 
SAE Reporting Form to 
Pfizer Safety Within 24 
Hours of Awareness 
SAE 
All 
All 
Nonserious AE 
All 
None 
Exposure to the study 
intervention under study 
during pregnancy or 
breastfeeding 
All AEs/SAEs associated 
with exposure during 
pregnancy or breastfeeding. 
All instances of EDP are 
reported (whether or not 
there is an associated 
SAE).* 
Note: Instances of EDP or 
EDB not associated with an 
AE or SAE are not captured 
in the CRF. 
All instances of EDB are 
reported (whether or not 
there is an associated 
SAE).** 
Environmental or 
occupational exposure to 
the product under study 
to a non-participant (not 
involving EDP or EDB). 
None. Exposure to a study 
non-participant is not 
collected on the CRF. 
The exposure (whether or 
not there is an associated 
AE or SAE) must be 
reported.*** 
* 
EDP (with or without an associated AE or SAE): any pregnancy information is reported to Pfizer 
Safety using the Vaccine SAE Reporting Form and EDP Supplemental Form; if the EDP is 
associated with an SAE, then the SAE is reported to Pfizer Safety using the Vaccine SAE Reporting 
Form. 

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AE and SAE Recording/Reporting 
** 
EDB is reported to Pfizer Safety using the Vaccine SAE Reporting Form, which would also include 
details of any SAE that might be associated with the EDB. 
*** 
Environmental or occupational exposure: AEs or SAEs associated with occupational exposure are 
reported to Pfizer Safety using the Vaccine SAE Reporting Form. 
• When an AE/SAE occurs, it is the responsibility of the investigator to review all 
documentation (eg, hospital progress notes, laboratory reports, and diagnostic 
reports) related to the event. 
• The investigator will then record all relevant AE/SAE information in the CRF. 
• It is not acceptable for the investigator to send photocopies of the participant’s 
medical records to Pfizer Safety in lieu of completion of the Vaccine SAE 
Reporting Form/AE/SAE CRF page. 
• There may be instances when copies of medical records for certain cases are 
requested by Pfizer Safety. In this case, all participant identifiers, with the 
exception of the participant number, will be redacted on the copies of the medical 
records before submission to Pfizer Safety. 
• The investigator will attempt to establish a diagnosis of the event based on signs, 
symptoms, and/or other clinical information. Whenever possible, the diagnosis 
(not the individual signs/symptoms) will be documented as the AE or SAE. 
 
 
Assessment of Intensity 
The investigator will make an assessment of intensity for each AE and SAE reported 
during the study and assign it to 1 of the following categories: 
• Mild: An event that is easily tolerated by the participant, causing minimal 
discomfort and not interfering with everyday activities. 
• Moderate: An event that causes sufficient discomfort and interferes with normal 
everyday activities. 
• Severe: An event that prevents normal everyday activities. An AE that is assessed 
as severe should not be confused with an SAE. Severe is a category utilized for 
rating the intensity of an event; and both AEs and SAEs can be assessed as severe. 
An event is defined as “serious” when it meets at least 1 of the predefined outcomes as 
described in the definition of an SAE, NOT when it is rated as severe. 

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Assessment of Intensity 
GRADE If required on the AE page of the CRF, the investigator will use the 
adjectives MILD, MODERATE, SEVERE, to describe the maximum 
intensity of the AE. For purposes of consistency, these intensity grades are 
defined as follows: 
1 
MILD 
Does not interfere with participant's usual function. 
2 
MODERATE 
Interferes to some extent with participant's usual 
function. 
3 
SEVERE 
Interferes significantly with participant's usual 
function. 
 
 
Assessment of Causality 
• The investigator is obligated to assess the relationship between study intervention 
and each occurrence of each AE or SAE. The investigator will use clinical 
judgment to determine the relationship. 
• A “reasonable possibility” of a relationship conveys that there are facts, evidence, 
and/or arguments to suggest a causal relationship, rather than a relationship cannot 
be ruled out. 
• Alternative causes, such as underlying disease(s), concomitant therapy, and other 
risk factors, as well as the temporal relationship of the event to study intervention 
administration, will be considered and investigated. 
• The investigator will also consult the IB and/or product information, for marketed 
products, in his/her assessment. 
• For each AE/SAE, the investigator must document in the medical notes that he/she 
has reviewed the AE/SAE and has provided an assessment of causality. 
• There may be situations in which an SAE has occurred and the investigator has 
minimal information to include in the initial report to the sponsor. However, it is 
very important that the investigator always make an assessment of causality 
for every event before the initial transmission of the SAE data to the sponsor. 
• The investigator may change his/her opinion of causality in light of follow-up 
information and send an SAE follow-up report with the updated causality 
assessment. 

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Assessment of Causality 
• The causality assessment is one of the criteria used when determining regulatory 
reporting requirements. 
• If the investigator does not know whether or not the study intervention caused the 
event, then the event will be handled as “related to study intervention” for reporting 
purposes, as defined by the sponsor. In addition, if the investigator determines that 
an SAE is associated with study procedures, the investigator must record this 
causal relationship in the source documents and CRF, and report such an 
assessment in the dedicated section of the Vaccine SAE Reporting Form and in 
accordance with the SAE reporting requirements. 
 
 
Follow-up of AEs and SAEs 
• The investigator is obligated to perform or arrange for the conduct of supplemental 
measurements and/or evaluations as medically indicated or as requested by the 
sponsor to elucidate the nature and/or causality of the AE or SAE as fully as 
possible. This may include additional laboratory tests or investigations, 
histopathological examinations, or consultation with other healthcare providers. 
• If a participant dies during participation in the study or during a recognized 
follow-up period, the investigator will provide Pfizer Safety with a copy of any 
postmortem findings including histopathology. 
• New or updated information will be recorded in the originally completed CRF. 
• The investigator will submit any updated SAE data to the sponsor within 24 hours 
of receipt of the information. 
 
10.3.6. Reporting of SAEs 
 
SAE Reporting to Pfizer Safety via an Electronic Data Collection Tool 
• The primary mechanism for reporting an SAE to Pfizer Safety will be the 
electronic data collection tool. 
• If the electronic system is unavailable, then the site will use the paper SAE data 
collection tool (see next section) in order to report the event within 24 hours. 
• The site will enter the SAE data into the electronic system as soon as the data 
become available. 

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SAE Reporting to Pfizer Safety via an Electronic Data Collection Tool 
• After the study is completed at a given site, the electronic data collection tool will 
be taken off-line to prevent the entry of new data or changes to existing data. 
• If a site receives a report of a new SAE from a study participant or receives updated 
data on a previously reported SAE after the electronic data collection tool has been 
taken off-line, then the site can report this information on a paper SAE form (see 
next section) or to Pfizer Safety by telephone. 
 
 
SAE Reporting to Pfizer Safety via Vaccine SAE Reporting Form 
• Facsimile transmission of the Vaccine SAE Reporting Form is the preferred 
method to transmit this information to Pfizer Safety. 
• In circumstances when the facsimile is not working, notification by telephone is 
acceptable with a copy of the Vaccine SAE Reporting Form sent by overnight mail 
or courier service. 
• Initial notification via telephone does not replace the need for the investigator to 
complete and sign the Vaccine SAE Reporting Form pages within the designated 
reporting time frames. 

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10.4. Appendix 4: Contraceptive Guidance 
10.4.1. Female Participant Reproductive Inclusion Criteria 
A female participant is eligible to participate if she is not pregnant or breastfeeding, and at 
least 1 of the following conditions applies: 
• Is not a WOCBP (see definitions below in Section 10.4.2). 
OR 
• Is a WOCBP and using an acceptable contraceptive method as described below 
during the intervention period (for a minimum of 28 days after the last dose of 
study intervention). The investigator should evaluate the effectiveness of the 
contraceptive method in relationship to the first dose of study intervention. 
The investigator is responsible for review of medical history, menstrual history, and recent 
sexual activity to decrease the risk for inclusion of a woman with an early undetected 
pregnancy. 
10.4.2. Woman of Childbearing Potential 
A woman is considered fertile following menarche and until becoming postmenopausal 
unless permanently sterile (see below). 
If fertility is unclear (eg, amenorrhea in adolescents or athletes) and a menstrual cycle cannot 
be confirmed before the first dose of study intervention, additional evaluation should be 
considered. 
Women in the following categories are not considered WOCBP: 
1. Premenopausal female with 1 of the following: 
• Documented hysterectomy; 
• Documented bilateral salpingectomy; 
• Documented bilateral oophorectomy. 
For individuals with permanent infertility due to an alternate medical cause other than the 
above, (eg, mullerian agenesis, androgen insensitivity), investigator discretion should be 
applied to determining study entry. 
Note: Documentation for any of the above categories can come from the site personnel’s 
review of the participant’s medical records, medical examination, or medical history 
interview. The method of documentation should be recorded in the participant’s medical 
record for the study. 

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2. Postmenopausal female: 
• A postmenopausal state is defined as no menses for 12 months without an alternative 
medical cause. In addition, a 
• high FSH level in the postmenopausal range must be used to confirm a 
postmenopausal state in women under 60 years of age and not using hormonal 
contraception or HRT. 
• Female on HRT and whose menopausal status is in doubt will be required to use 
one of the nonestrogen hormonal highly effective contraception methods if they 
wish to continue their HRT during the study. Otherwise, they must discontinue 
HRT to allow confirmation of postmenopausal status before study enrollment. 
10.4.3. Contraception Methods 
1. Implantable progestogen-only hormone contraception associated with inhibition of 
ovulation. 
2. Intrauterine device. 
3. Intrauterine hormone-releasing system. 
4. Bilateral tubal occlusion. 
5. Vasectomized partner: 
• Vasectomized partner is a highly effective contraceptive method provided that the 
partner is the sole sexual partner of the woman of childbearing potential and the 
absence of sperm has been confirmed. If not, an additional highly effective method 
of contraception should be used. The spermatogenesis cycle is approximately 
90 days. 
6. Combined (estrogen- and progestogen-containing) hormonal contraception associated 
with inhibition of ovulation: 
• Oral; 
• Intravaginal; 
• Transdermal. 
7. Progestogen-only hormone contraception associated with inhibition of ovulation: 
• Oral; 
• Injectable. 

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8. Sexual abstinence: 
• Sexual abstinence is considered a highly effective method only if defined as 
refraining from heterosexual intercourse during the entire period of risk associated 
with the study intervention. The reliability of sexual abstinence needs to be evaluated 
in relation to the duration of the study and the preferred and usual lifestyle of the 
participant. 
9. Progestogen-only oral hormonal contraception where inhibition of ovulation is not the 
primary mode of action. 
10. Male or female condom with or without spermicide. 
11. Cervical cap, diaphragm, or sponge with spermicide. 
12. A combination of male condom with either cervical cap, diaphragm, or sponge with 
spermicide (double-barrier methods). 

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10.5. Appendix 5: Liver Safety: Suggested Actions and Follow-up Assessments 
Potential Cases of Drug-Induced Liver Injury 
Humans exposed to a drug who show no sign of liver injury (as determined by elevations in 
transaminases) are termed “tolerators,” while those who show transient liver injury, but adapt 
are termed “adaptors.” In some participants, transaminase elevations are a harbinger of a 
more serious potential outcome. These participants fail to adapt and therefore are 
"susceptible" to progressive and serious liver injury, commonly referred to as DILI. 
Participants who experience a transaminase elevation above 3 × ULN should be monitored 
more frequently to determine if they are an “adaptor” or are “susceptible.” 
LFTs are not required as a routine safety monitoring procedure in this study. However, 
should an investigator deem it necessary to assess LFTs because a participant presents with 
clinical signs/symptoms, such LFT results should be managed and followed as described 
below. 
In the majority of DILI cases, elevations in AST and/or ALT precede TBili elevations 
(>2 × ULN) by several days or weeks. The increase in TBili typically occurs while 
AST/ALT is/are still elevated above 3 × ULN (ie, AST/ALT and TBili values will be 
elevated within the same laboratory sample). In rare instances, by the time TBili elevations 
are detected, AST/ALT values might have decreased. This occurrence is still regarded as a 
potential DILI. Therefore, abnormal elevations in either AST OR ALT in addition to TBili 
that meet the criteria outlined below are considered potential DILI (assessed per Hy’s law 
criteria) cases and should always be considered important medical events, even before all 
other possible causes of liver injury have been excluded. 
The threshold of laboratory abnormalities for a potential DILI case depends on the 
participant’s individual baseline values and underlying conditions. Participants who present 
with the following laboratory abnormalities should be evaluated further as potential DILI 
(Hy’s law) cases to definitively determine the etiology of the abnormal laboratory values: 
• Participants with AST/ALT and TBili baseline values within the normal range who 
subsequently present with AST OR ALT values >3 × ULN AND a TBili value 
>2 × ULN with no evidence of hemolysis and an alkaline phosphatase value 
<2 × ULN or not available. 
• For participants with baseline AST OR ALT OR TBili values above the ULN, the 
following threshold values are used in the definition mentioned above, as needed, 
depending on which values are above the ULN at baseline: 
• Preexisting AST or ALT baseline values above the normal range: AST or ALT 
values >2 times the baseline values AND >3 × ULN; or >8 × ULN (whichever is 
smaller). 

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• Preexisting values of TBili above the normal range: TBili level increased from 
baseline value by an amount of at least 1 × ULN or if the value reaches >3 × ULN 
(whichever is smaller). 
Rises in AST/ALT and TBili separated by more than a few weeks should be assessed 
individually based on clinical judgment; any case where uncertainty remains as to whether it 
represents a potential Hy’s law case should be reviewed with the sponsor. 
The participant should return to the investigator site and be evaluated as soon as possible, 
preferably within 48 hours from awareness of the abnormal results. This evaluation should 
include laboratory tests, detailed history, and physical assessment. 
In addition to repeating measurements of AST and ALT and TBili for suspected cases of 
Hy’s law, additional laboratory tests should include albumin, CK, direct and indirect 
bilirubin, GGT, PT/INR, total bile acids, and alkaline phosphatase. Consideration should 
also be given to drawing a separate tube of clotted blood and an anticoagulated tube of blood 
for further testing, as needed, for further contemporaneous analyses at the time of the 
recognized initial abnormalities to determine etiology. A detailed history, including relevant 
information, such as review of ethanol, acetaminophen/paracetamol (either by itself or as a 
coformulated product in prescription or over-the-counter medications), recreational drug, 
supplement (herbal) use and consumption, family history, sexual history, travel history, 
history of contact with a jaundiced person, surgery, blood transfusion, history of liver or 
allergic disease, and potential occupational exposure to chemicals, should be collected. 
Further testing for acute hepatitis A, B, C, D, and E infection and liver imaging (eg, biliary 
tract) and collection of serum samples for acetaminophen/paracetamol drug and/or protein 
adduct levels may be warranted. 
All cases demonstrated on repeat testing as meeting the laboratory criteria of AST/ALT and 
TBili elevation defined above should be considered potential DILI (Hy’s law) cases if no 
other reason for the LFT abnormalities has yet been found. Such potential DILI (Hy’s law) 
cases are to be reported as SAEs, irrespective of availability of all the results of the 
investigations performed to determine etiology of the LFT abnormalities. 
A potential DILI (Hy’s law) case becomes a confirmed case only after all results of 
reasonable investigations have been received and have excluded an alternative etiology. 

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10.6. Appendix 6: Protocol Amendment History 
The Protocol Amendment Summary of Changes Table for the current amendment is located 
directly before the table of contents (TOC). The protocol amendment summary of changes 
tables for past amendment(s) can be found below: 
Amendment 2 (11 April 2022) 
Overall Rationale for the Amendment: Study sample size and statistical analyses have 
been modified based on a strategic decision to describe the safety and immunogenicity in 
nonpregnant women, with a plan for a future study to evaluate the safety and 
immunogenicity in pregnant women. 
 
Section # and Name 
Description of Change 
Brief Rationale 
Section 1.1: Synopsis 
Section 2: Introduction 
Section 2.1: Study Rationale 
Section 2.2.2: Maternal 
Immunization as an Approach to 
Prevent Disease in Infants and 
Pregnant Women 
Section 2.3.1: Risk Assessment 
Section 3: Objectives, Estimands, 
and Endpoints 
Section 4.1: Overall Design 
Section 4.3: Justification for 
Dose 
Section 5.2: Exclusion Criteria 
Section 6.5.3: Recording 
Nonstudy Vaccinations and 
Concomitant Medications 
Section 9.1.1: Statistical 
Hypotheses 
Section 9.1.2: Estimands 
Section 9.2: Sample Size 
Determination 
Section 9.4.2: Immunogenicity 
Analyses 
• Modified the primary 
immunogenicity 
objective and 
estimands to align 
with strategic 
decision of 
evaluating the 
immunogenicity 
interference with 
coadministration of 
Tdap and GBS6. 
• Revised the study 
sample size to align 
with modified safety 
and immunogenicity 
objective. 
• Modified the 
hypothesis-based 
noninferiority testing 
analysis for the 
primary 
immunogenicity 
endpoints to 
descriptive analysis 
due to the change in 
the primary study 
immunogenicity 
objective. 
• Modified appropriate 
statistical sections 
due to updates to the 
• The study aims to have 
a sufficient number of 
participants in order to 
describe the safety and 
immunogenicity of 
coadministration of 
GBS6 and Tdap. 
• The study design is 
descriptive in nature, 
and descriptive 
statistics will be 
provided for the 
primary safety and 
primary 
immunogenicity 
endpoints. 

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Section # and Name 
Description of Change 
Brief Rationale 
primary 
immunogenicity 
objectives and 
estimands. 
Section 1.1: Synopsis 
Section 1.3: Schedule of 
Activities 
Section 2.3.3: Overall 
Benefit/Risk Conclusion 
Section 3: Objectives, Estimands, 
and Endpoints 
Section 7.2: Participant 
Discontinuation/Withdrawal 
From the Study 
Former Section 8.1.3: GBS 
Microbiological Cultures 
Section 8.1.3: Biological 
Samples 
Section 8.11.1: Visit 1 – 
Vaccination (Day 1) 
Section 8.11.2: Visit 2 – 1-Month 
Follow-up Visit (28-38 Days 
After Visit 1) 
• Removed swabs for 
GBS microbiological 
cultures. 
• Due to the reduction in 
study participants, 
there is no added value 
in taking the 
microbiological 
cultures. 
Section 1.1: Synopsis 
Section 1.3: Schedule of 
activities 
Section 3: Objectives, Estimands, 
and Endpoints 
Section 4.1: Overall Design 
Section 6.5.3: Recording 
Nonstudy Vaccinations and 
Concomitant Medications 
Section 8.1: Efficacy and/or 
Immunogenicity Assessments 
Section 8.3.1: Time Period and 
Frequency for Collecting AE and 
SAE Information 
Former Section 8.11.3: Visit 3 – 
6-Month Telephone Call 
Follow-up Visit (160-200 Days 
After Visit 1) 
Section 9.1.2: Estimands 
• Modified the study 
follow-up period for 
participants to 
approximately 
1 month after 
vaccination to align 
with the study 
objectives. 
• Safety will be assessed 
through 1 month after 
vaccination. Immune 
responses to GBS6 and 
Tdap antigens will be 
measured 1 month 
after vaccination. 

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Section # and Name 
Description of Change 
Brief Rationale 
Section 8.1.1: GBS Vaccine 
Antibody Testing 
Section 8.1.2: Tdap Antibody 
Testing 
• Added an unblinded 
statistician who will 
identify participants 
from the dose 
groups. 
• The addition of an 
unblinded statistician 
will allow study 
participants to be 
divided by 
immunogenicity 
assessment in order to 
decrease the number of 
assays required to be 
analyzed. 
Document History 
Section 5.2: Exclusion Criteria 
Section 5.3.1: Contraception 
Section 5.5: Criteria for 
Temporarily Delaying 
Enrollment/Randomization/Study 
Intervention Administration of 
Study Intervention 
Section 6: Study Intervention(s) 
and Concomitant Therapy 
Section 7.2.1: Withdrawal of 
Consent 
Section 8.2.5: Pregnancy Testing 
Section 8.3: Adverse Events and 
Serious Adverse Events 
Section 8.3.1: Time Period and 
Frequency for Collecting AE and 
SAE Information 
Section 8.3.5: Environmental 
Exposure, Exposure During 
Pregnancy or Breastfeeding, and 
Occupational Exposure 
Section 10.1.3: Informed 
Consent Process 
Section 10.1.7: Source 
Documents 
Section 10.1.10: Sponsor’s 
Qualified Medical Personnel 
Section 10.3.2: Definition of an 
SAE 
Section 10.3.5: 
Recording/Reporting and 
Follow-up of AEs and/or SAEs 
• Updated wording to 
match mandatory 
text from the new 
protocol template. 
• These changes were 
incorporated to align 
with the protocol 
template changes. 

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Section # and Name 
Description of Change 
Brief Rationale 
Section 10.6: Appendix 6: 
Protocol Amendment History 
 
Amendment 1 (22 January 2021) 
Overall Rationale for the Amendment: The GBS6 dose formulation has been updated to 
remove AlPO4 since interim data from Study C1091002 show acceptable immune responses 
were achieved with the formulation that did not contain AlPO4. 
 
Section # 
and Name 
Description of Change 
Brief Rationale 
Section 1 
Section 4.1 
Section 4.3 
Section 6.1 
The GBS6 dose formulation has 
been updated to remove AlPO4 
The GBS6 dose formulation has been 
updated to remove AlPO4 since interim 
data from Study C1091002 shows 
acceptable immune responses were 
achieved with the formulation that did 
not contain AlPO4. 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
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Final Protocol Amendment 3, 04 October 2022 
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10.7. Appendix 7: Abbreviations 
The following is a list of abbreviations that may be used in the protocol. 
 
Abbreviation 
Term 
ACIP 
Advisory Committee on Immunization Practices 
ADE 
adverse device effect 
AE 
adverse event 
AlPO4 
aluminum phosphate 
ALT 
alanine aminotransferase 
AST 
aspartate aminotransferase 
BLQ 
below the limit of quantitation 
CBER 
Center for Biologics Evaluation and Research (United States) 
CFR 
Code of Federal Regulations 
CI 
confidence interval 
CIOMS 
Council for International Organizations of Medical Sciences 
CK 
creatine kinase 
CONSORT 
Consolidated Standards of Reporting Trials 
CPS 
capsular polysaccharide 
CRF 
case report form 
CRM197 
cross-reactive material 197 
CRO 
contract research organization 
CSR 
clinical study report 
DILI 
drug-induced liver injury 
DNA 
deoxyribonucleic acid 
DTd 
diphtheria toxoid 
DU 
dispensable unit 
EC 
ethics committee 
ECG 
electrocardiogram 
eCRF 
electronic case report form 
e-diary 
electronic diary 
E-DMC 
external data monitoring committee 
EDP 
exposure during pregnancy 
EMA 
European Medicines Agency 
EOD 
early-onset disease 
EU 
European Union 
EudraCT 
European Clinical Trials Database 
EU/mL 
endotoxin units per milliliter 
FDA 
Food and Drug Administration (United States) 
FHA 
filamentous hemagglutinin 
FIH 
first-in-human 
FIM 
fimbriae 
FSH 
follicle-stimulating hormone 
GBS 
group B streptococcus 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
Page 88 
 
 
 
Abbreviation 
Term 
GBS6 
group B streptococcus 6-valent polysaccharide conjugate vaccine 
GCP 
Good Clinical Practice 
GGT 
gamma-glutamyl transferase 
GMC 
geometric mean concentration 
GMFR 
geometric mean fold rise 
GMR 
geometric mean ratio 
GMT 
geometric mean titer 
HIPAA 
Health Insurance Portability and Accountability Act 
HRT 
hormone replacement therapy 
IAP 
intrapartum antibiotic prophylaxis 
IB 
investigator’s brochure 
ICD 
informed consent document 
ICH 
International Council for Harmonisation 
ID 
identification 
IgG 
immunoglobulin G 
IND 
investigational new drug 
INR 
international normalized ratio 
IP manual 
investigational product manual 
IPAL 
Investigational Product Accountability Log 
IRB 
institutional review board 
IRT 
interactive response technology 
ISF 
investigator site file 
IU/mL 
international units per milliliter 
IWR 
interactive Web-based response 
Lf 
flocculation units 
LFT 
liver function test 
LLOQ 
lower limit of quantitation 
LMIC 
low- and middle-income country 
Ln 
natural logarithm 
LOD 
late-onset disease 
MAE 
medically attended adverse event 
MCAR 
missing completely at random 
MedDRA 
Medical Dictionary for Regulatory Activities 
mITT 
modified intent-to-treat 
mIU/mL 
milli-international units per milliliter 
N/A 
not applicable 
NaCl 
sodium chloride 
PRN 
pertactin 
PT 
prothrombin time 
RCDC 
reverse cumulative distribution curve 
RSV 
respiratory syncytial virus 
SADE 
serious adverse device effect 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
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Page 89 
 
 
 
Abbreviation 
Term 
SAE 
serious adverse event 
SAP 
statistical analysis plan 
SoA 
schedule of activities 
SOP 
standard operating procedure 
SRM 
study reference manual 
SRSD 
single reference safety document 
SUSAR 
suspected unexpected serious adverse reaction 
TBili 
total bilirubin 
Td 
tetanus and diphtheria vaccine 
Tdap 
tetanus toxoid, diphtheria toxoid, and acellular pertussis vaccine 
TTd 
tetanus toxoid 
ULN 
upper limit of normal 
US 
United States 
USPI 
United States prescribing information 
WOCBP 
woman/women of childbearing potential 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
Page 90 
 
 
11. REFERENCES 
 
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Lin FYC, Philips JB 3rd, Azimi PH, et al. Level of maternal antibody required to protect 
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Phares CR, Lynfield R, Farley MM, et al. Epidemiology of invasive group B 
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Edmond KM, Kortsalioudaki C, Scott S, et al. Group B streptococcal disease in infants 
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Skoff TH, Farley MM, Petit S, et al. Increasing burden of invasive group B 
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Lamagni TL, Keshishian C, Efstratiou A, et al. Emerging trends in the epidemiology of 
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Deutscher M, Lewis M, Zell ER, et al. Incidence and severity of invasive 
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Edwards MS, Nizet V, Baker CJ. Group B streptococcal infections. In: Remington JS, 
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Baker CJ. The spectrum of perinatal group B streptococcal disease. Vaccine 
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Smith EM, Khan MA, Reingold A, et al. Group B streptococcus infections of soft tissue 
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Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
PFIZER CONFIDENTIAL 
Page 91 
 
 
 
12 
Natarajan P, Poretz DM. The increasing threat of group B streptococcus infection in 
adults [abstract 738]. Open Forum Infect Dis 2014;1(Suppl 1):S208. 
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Munoz FM. Current challenges and achievements in maternal immunization research. 
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Berenson AB, Hirth JM, Rahman M, et al. Maternal and infant outcomes among women 
vaccinated against pertussis during pregnancy. Hum Vaccin Immunother 
2016;12(8):1965-71. 
15 
Swamy GK, Beigi RH. Maternal benefits of immunization during pregnancy. Vaccine 
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Englund JA. The influence of maternal immunization on infant immune responses. 
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Zaman K, Roy E, Arifeen SE, et al. Effectiveness of maternal influenza immunization in 
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Madhi SA, Cutland CL, Kuwanda L, et al. Influenza vaccination of pregnant women and 
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Munoz FM, Bond NH, Maccato M, et al. Safety and immunogenicity of tetanus 
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Layton JB, Butler AM, Li D, et al. Prenatal Tdap immunization and risk of maternal and 
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Harper SA, Fukuda K, Uyeki TM, et al; Centers for Disease Control and Prevention 
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Lindsey B, Kampmann B, Jones C. Maternal immunization as a strategy to decrease 
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Centers for Disease Control and Prevention. Updated recommendations for use of 
tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine (Tdap) in 
pregnant women--Advisory Committee on Immunization Practices (ACIP), 2012. 
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Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
Protocol C1091005 
Final Protocol Amendment 3, 04 October 2022 
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Page 92 
 
 
 
24 
Australian Government Department of Health. Pertussis (whooping cough). In: 
Australian immunisation handbook. Available from: 
https://immunisationhandbook.health.gov.au/vaccine-preventable-diseases/ 
pertussis-whooping-cough. Updated: 20 Sep 2019. Accessed: 24 Oct 2019. 
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Bekker V, Bijlsma MW, van de Beek D, et al. Incidence of invasive group B 
streptococcal disease and pathogen genotype distribution in newborn babies in the 
Netherlands over 25 years: a nationwide surveillance study. Lancet Infect Dis 
2014;14(11):1083-89. 
26 
Baker CJ, Carey VJ, Rench MA, et al. Maternal antibody at delivery protects neonates 
from early onset group B streptococcal disease. J Infect Dis 2014;209(5):781-8. 
27  Dangor Z, Kwatra G, Izu A, et al. Correlates of protection of serotype-specific capsular 
antibody and invasive group B streptococcus disease in South African infants. Vaccine 
2015;33(48):6793-9. 
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Fabbrini M, Rigat F, Rinaudo CD, et al. The protective value of maternal group B 
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Infect Dis 2016;63(6):746-53. 
29 
Lin FY, Philips JB 3rd, Azimi PH, et al. Level of maternal antibody required to protect 
neonates against early-onset disease caused by group B streptococcus type Ia: a 
multicenter, seroepidemiology study. J Infect Dis 2001;184(8):1022-8. 
30  Lin FYC, Weisman LE, Azimi PH, et al. Level of maternal IgG anti-group B 
streptococcus type III antibody correlated with protection of neonates against 
early-onset disease caused by this pathogen. J Infect Dis 2004;190(5):928-34. 
31 
Dzanibe S, Madhi SA. Systematic review of the clinical development of group B 
streptococcus serotype-specific capsular polysaccharide-based vaccines. Expert Rev 
Vaccines 2018;17(7):635-51. 
 
32  Madhi SA, Cutland CL, Jose L, et al. Safety and immunogenicity of an investigational 
maternal trivalent group B streptococcus vaccine in healthy women and their infants: a 
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33 
Fluarix [package insert]. Research Triangle Park, NC: GlaxoSmithKline; 2020. 
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Afluria [package insert]. Summit, NJ: Seqirus; 2020. 
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Afluria Quadrivalent [package insert]. Summit, NJ: Seqirus; 2020. 

Group B Streptococcus 6-Valent Polysaccharide Conjugate Vaccine (GBS6) 
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Final Protocol Amendment 3, 04 October 2022 
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Page 93 
 
 
 
36 US Food and Drug Administration. Guidance for industry: toxicity grading scale for 
healthy adult and adolescent volunteers enrolled in preventive vaccine clinical trials. 
Rockville, MD: Center for Biologics Evaluation and Research; September 2007. 

 
Signed By: 
Date(GMT) 
Signing Capacity 
 
Document Approval Record 
 
 
C1091005 Clinical Protocol Amendment 3 Clean Copy, 04 Oct 2022 
 
A PHASE 2B, PLACEBO-CONTROLLED, RANDOMIZED, OBSERVE 
R-BLINDED TRIAL TO EVALUATE THE SAFETY, TOLERABILITY, A 
ND IMMUNOGENICITY OF A MULTIVALENT GROUP B STREPTOC 
OCCUS VACCINE WHEN ADMINISTERED CONCOMITANTLY WITH 
TETANUS, DIPHTHERIA, AND ACELLULAR PERTUSSIS VACCINE ( 
TDAP) IN HEALTHY NONPREGNANT WOMEN 18 THROUGH 49 YE 
ARS OF AGE 
 
 
PPD 
  
PPD 
 
04-Oct-2022 14 45 29 
Final Approval 
 
04-Oct-2022 14 53 49 
Final Approval 
Document Name: 
Document Title: