Randomized Phase I/II Study of the Safety and Immunogenicity of a Single Dose of the Recombinant Live-Attenuated Respiratory Syncytial Virus (RSV) Vaccines RSV ΔNS2/Δ1313/I1314L, RSV 6120/ΔNS2/1030s, RSV 276 or Placebo, Delivered as Nose Drops to RSV-Seronegative Children 6 to 24 Months of Age
Phase: PHASE1
Conditions: Respiratory Syncytial Virus (RSV)
Sponsor: National Institute of Allergy and Infectious Diseases (NIAID)

IMPAACT 2021 
 
 
Randomized Phase I/II Study of the Safety and Immunogenicity of a 
Single Dose of the Recombinant Live-Attenuated Respiratory 
Syncytial Virus (RSV) Vaccines RSV ΔNS2/Δ1313/I1314L, RSV 
6120/ΔNS2/1030s, RSV 276 or Placebo, Delivered as Nose Drops to 
RSV-Seronegative Children 6 to 24 Months of Age 
 
A Study of the International Maternal Pediatric Adolescent  
AIDS Clinical Trials Network  
 
 
 
 
Sponsored by: 
National Institute of Allergy and Infectious Diseases  
Eunice Kennedy Shriver  
National Institute of Child Health and Human Development  
National Institute of Mental Health 
 
 
 
DAIDS Study ID # 38530 
IND # 018943 Held by DAIDS 
 
 
 
Protocol Chairs: 
Coleen Cunningham, MD 
 
Ruth Karron, MD 
 
Protocol Vice Chair: 
Elizabeth J. McFarland, MD 
 
 
 
NIAID Medical Officers:  
Dwight Yin, MD, PhD, MPH  
Patrick Jean-Philippe, MD 
 
 
NICHD Medical Officer: 
Jack Moye, Jr., MD 
 
Clinical Research Managers: 
Charlotte Perlowski, MSPH 
Jennifer Libous, MS, CCRP 
Haley Brozik, MSc 
 
FINAL Version 3.0 
 
 
28 April 2022 

 
IMPAACT 2021, FINAL Version 3.0 
Page 2 of 106 
28 April 2022 
IMPAACT 2021 
Randomized Phase I/II Study of the Safety and Immunogenicity of a Single Dose 
of the Recombinant Live-Attenuated Respiratory Syncytial Virus (RSV) Vaccines 
RSV ΔNS2/Δ1313/I1314L, RSV 6120/ΔNS2/1030s, RSV 276 or Placebo, Delivered 
as Nose Drops to RSV-Seronegative Children 6 to 24 Months of Age 
 
TABLE OF CONTENTS 
 
TABLE OF CONTENTS ............................................................................................................. 2 
LIST OF TABLES ....................................................................................................................... 5 
LIST OF FIGURES .................................................................................................................... 5 
PROTOCOL SIGNATURE PAGE .............................................................................................. 6 
ABBREVIATIONS AND ACRONYMS ........................................................................................ 7 
PROTOCOL TEAM ROSTER ...................................................................................................10 
STUDY SITE ROSTER .............................................................................................................13 
SCHEMA ..................................................................................................................................15 
1 
INTRODUCTION ...........................................................................................................18 
1.1 
Overview ......................................................................................................................................... 18 
1.2 
Background ..................................................................................................................................... 21 
1.3 
Prior Research................................................................................................................................. 24 
1.3.1 Experimental Vaccines against Respiratory Syncytial Virus ....................................................... 24 
1.3.2 Preclinical Studies ....................................................................................................................... 25 
1.3.3 Previous Clinical Experience ....................................................................................................... 27 
1.4 
Rationale ......................................................................................................................................... 30 
1.5 
Hypotheses ..................................................................................................................................... 33 
2 
OBJECTIVES ................................................................................................................33 
2.1 
Primary Objectives .......................................................................................................................... 33 
2.2 
Secondary Objectives ...................................................................................................................... 33 
2.3 
Exploratory Objectives ..................................................................................................................... 33 
3 
STUDY DESIGN ...........................................................................................................34 
4 
STUDY POPULATION ..................................................................................................36 
4.1 
Inclusion Criteria .............................................................................................................................. 37 
4.2 
Exclusion Criteria............................................................................................................................. 37 
4.3 
Co-Enrollment Considerations ......................................................................................................... 40 
4.4 
Recruitment, Screening, and Enrollment Process ........................................................................... 40 
4.5 
Participant Retention ....................................................................................................................... 41 
4.6 
Participant Withdrawal or Termination from the Study .................................................................... 41 
5 
STUDY PRODUCT CONSIDERATIONS .......................................................................42 
5.1 
Study Products ................................................................................................................................ 42 
5.2 
Study Product Regimens ................................................................................................................. 42 
5.3 
Study Product Formulation .............................................................................................................. 42 
5.3.1 Vaccines ...................................................................................................................................... 42 
5.3.2 Diluent for RSV ΔNS2/Δ1313/I1314L and RSV 6120/ΔNS2/1030s ............................................ 43 
5.3.3 Placebo for RSV ΔNS2/Δ1313/I1314L and RSV 6120/ΔNS2/1030s .......................................... 43 
5.4 
Study Product Storage .................................................................................................................... 43 
5.5 
Study Product Preparation .............................................................................................................. 44 
5.5.1 Preparation of Placebo for RSV ΔNS2/Δ1313/I1314L and RSV 6120/ΔNS2/1030s ................... 44 
5.5.2 Preparation of Live Recombinant Respiratory Syncytial Virus RSV ΔNS2/Δ1313/I1314L and 
RSV 6120/ΔNS2/1030s ............................................................................................................... 44 
5.6 
Study Product Administration Procedure ......................................................................................... 45 
5.7 
Study Product Acquisition ................................................................................................................ 45 
5.8 
Study Product Accountability ........................................................................................................... 46 

 
IMPAACT 2021, FINAL Version 3.0 
Page 3 of 106 
28 April 2022 
5.9 
Disposition of Used Study Product .................................................................................................. 46 
5.10 
Final Disposition of Study Products ................................................................................................. 46 
5.11 
Concomitant Medications ................................................................................................................ 46 
5.11.1 Prohibited Concomitant Medications ........................................................................................... 46 
5.11.2 Precautionary Concomitant Medications ..................................................................................... 46 
6 
STUDY VISITS AND PROCEDURES............................................................................47 
6.1 
Screening Visit................................................................................................................................. 47 
6.2 
Enrollment Visit/Study Product Administration (Day 0) .................................................................... 48 
6.3 
Acute Phase Contacts and Visit ...................................................................................................... 51 
6.3.1 Acute Phase Contacts: Daily on Study Days 1-27 (±1 day) ........................................................ 51 
6.3.2 Acute Phase Visit: Study Day 28 (-1/+4 days) ............................................................................ 51 
6.4 
Post-Acute Phase (Days 29 to 56) .................................................................................................. 52 
6.4.1 Day 29 Contact (+1 day) ............................................................................................................. 52 
6.4.2 Day 56 Visit (+7 Days) ................................................................................................................ 53 
6.5 
Period after Day 56 Visit until October 31st or as specified in the MOP ........................................... 53 
6.6 
RSV Season Surveillance (November 1st through March 31st following study product administration 
or as specified in the MOP) ............................................................................................................. 53 
6.7 
Post-RSV Season Study Visit (April 1st to 30th in the calendar year following study product 
administration) ................................................................................................................................. 54 
6.8 
Illness Visit ...................................................................................................................................... 54 
6.9 
Early Discontinuation Study Visit ..................................................................................................... 56 
6.10 
Additional Considerations for Laboratory Procedures ..................................................................... 56 
6.10.1 Specimen Collection ................................................................................................................... 56 
6.10.2 Specimen Preparation, Testing, Storage, and Shipping.............................................................. 56 
6.10.3 Biohazard Containment ............................................................................................................... 58 
7 
SAFETY ASSESSMENT, MONITORING, AND REPORTING .......................................58 
7.1 
Safety-Related Roles and Responsibilities ...................................................................................... 58 
7.1.1 Site Investigators ......................................................................................................................... 58 
7.1.2 Protocol Safety Review Team (PSRT) ........................................................................................ 58 
7.1.3 Data and Safety Monitoring Board (DSMB) ................................................................................ 59 
7.2 
Safety-Related Data Collection ....................................................................................................... 59 
7.3 
Expedited Adverse Event (EAE) Reporting ..................................................................................... 63 
7.3.1 EAE Reporting to DAIDS............................................................................................................. 63 
7.3.2 EAE Reporting Requirements for this Study ............................................................................... 63 
7.3.3 Grading Severity of Events (applies to EAEs and all other adverse events) ............................... 64 
7.3.4 EAE Reporting Period ................................................................................................................. 65 
8 
PARTICIPANT MANAGEMENT ....................................................................................65 
8.1 
Management of Adverse Events ..................................................................................................... 65 
9 
STATISTICAL CONSIDERATIONS ...............................................................................66 
9.1 
General Design Issues .................................................................................................................... 66 
9.2 
Objectives and Outcome Measures ................................................................................................ 67 
9.2.1 Primary Outcome Measures........................................................................................................ 67 
9.2.2 Secondary Outcome Measures ................................................................................................... 68 
9.2.3 Exploratory Outcome Measures .................................................................................................. 68 
9.3 
Randomization and Sample Size .................................................................................................... 70 
9.3.1 Randomization ............................................................................................................................ 70 
9.3.2 Sample Size ................................................................................................................................ 70 
9.4 
Monitoring ........................................................................................................................................ 73 
9.4.1 Monitoring of Accrual and Retention by the Protocol Team ........................................................ 74 
9.4.2 Monitoring of Safety by the Protocol Safety Review Team (PSRT) and ad hoc DSMB Expert 
Members ..................................................................................................................................... 74 
9.4.3 Monitoring by the NIAID Intramural Data and Safety Monitoring Board ...................................... 75 
9.5 
Analyses .......................................................................................................................................... 76 

 
IMPAACT 2021, FINAL Version 3.0 
Page 4 of 106 
28 April 2022 
9.5.1 Primary Safety Outcome Measures ............................................................................................ 76 
9.5.2 Primary Immunogenicity Outcome Measures ............................................................................. 77 
9.5.3 Secondary Outcome Measures ................................................................................................... 77 
9.5.4 Exploratory Outcome Measures .................................................................................................. 77 
10 
DATA HANDLING AND RECORD KEEPING ................................................................78 
10.1 
Data Management Responsibilities ................................................................................................. 78 
10.2 
Essential and Source Documents and Access to Source Data ....................................................... 78 
10.3 
Clinical Investigator’s Brochure ....................................................................................................... 79 
10.4 
Quality Control and Quality Assurance ............................................................................................ 79 
11 
CLINICAL SITE MONITORING .....................................................................................79 
12 
HUMAN SUBJECTS PROTECTIONS ...........................................................................80 
12.1 
Institutional Review Board/Ethics Committee Review and Approval ............................................... 80 
12.2 
Vulnerable Participants .................................................................................................................... 80 
12.3 
Informed Consent ............................................................................................................................ 81 
12.4 
Potential Benefits............................................................................................................................. 81 
12.5 
Potential Risks ................................................................................................................................. 82 
12.5.1 Venipuncture ............................................................................................................................... 82 
12.5.2 Nasal Swabs ............................................................................................................................... 82 
12.5.3 Receipt of Study Product ............................................................................................................ 82 
12.6 
Reimbursement/Compensation ....................................................................................................... 82 
12.7 
Privacy and Confidentiality .............................................................................................................. 82 
12.8 
Management of Incidental Findings ................................................................................................. 83 
13 
ADMINISTRATIVE PROCEDURES ..............................................................................83 
13.1 
Regulatory Oversight ....................................................................................................................... 83 
13.2 
Protocol Registration ....................................................................................................................... 83 
13.3 
Study Implementation ...................................................................................................................... 84 
13.4 
Protocol Deviation Reporting ........................................................................................................... 84 
13.5 
ClinicalTrials.gov ............................................................................................................................. 85 
14 
PUBLICATIONS ............................................................................................................85 
15 
REFERENCES ..............................................................................................................86 
APPENDICES ...........................................................................................................................89 
Appendix I: Schedule of Events: Screening, Acute Phase, and Post-Acute Phase ....................89 
Appendix II: Schedule of Events: RSV Seasonal Surveillance and Post-season Sampling .......90 
Appendix III: Definitions of Solicited Adverse Events ................................................................91 
Appendix IV: RSV Seasonality in Baltimore ..............................................................................92 
Appendix V: Operational Guidance for Study Implementation at Sites Experiencing Operational 
Disruptions Due to COVID-19 ........................................................................................93 
Appendix VI: Informed Consent Form for Study Participation ....................................................95 
 
 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 5 of 106 
28 April 2022 
 
LIST OF TABLES 
 
Table 1: Overview of recent RSV vaccine candidates with M2-2 or NS2 deletiona .................... 19 
Table 2: Overview of RSV vaccine candidates with NS2 or M2-2 deletion to be studied in 
IMPAACT 2021........................................................................................................... 21 
Table 3: Criteria for Including a Vaccine in IMPAACT 2021 ...................................................... 31 
Table 4: Post-Accrual Season Study Review Criteria ................................................................ 32 
Table 5: AE eCRF Entry Requirements ..................................................................................... 62 
Table 6: Grading Table for Solicited AEs................................................................................... 64 
Table 7: Fever Grading* ............................................................................................................ 64 
Table 8: EAE Reporting ............................................................................................................ 65 
Table 9: Exact 95% confidence intervals for various observed vaccine response rates with a 
sample size of 38 ........................................................................................................ 71 
Table 10: Differences (exact 95% CIs) in observed rates of AEs between vaccine and placebo 
arms ........................................................................................................................... 72 
Table 11: Exact 95% confidence intervals for range of numbers of observed events among 40 
participants ................................................................................................................. 72 
Table 12: Groups responsible for monitoring ............................................................................. 73 
 
 
LIST OF FIGURES 
 
Figure 1: Study Overview .......................................................................................................... 17 
Figure 2: Initial Study Phases and Additional Study Timeframes ............................................... 36 
Figure 3: Investigational Product Label (Enlarged Sample) ....................................................... 43 
 
 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 6 of 106 
28 April 2022 
IMPAACT 2021 
Randomized Phase I/II Study of the Safety and Immunogenicity of a Single Dose 
of the Recombinant Live-Attenuated Respiratory Syncytial Virus (RSV) Vaccines 
RSV ΔNS2/Δ1313/I1314L, RSV 6120/ΔNS2/1030s, RSV 276 or Placebo, Delivered 
as Nose Drops to RSV-Seronegative Children 6 to 24 Months of Age 
 
 
DAIDS Study ID # 38530 
 
Version 3.0 
 
PROTOCOL SIGNATURE PAGE 
 
 
I will conduct this study in accordance with the provisions of this protocol and all applicable protocol-
related documents. I agree to conduct this study in compliance with United States (US) Health and 
Human Service regulations (45 CFR 46); applicable US Food and Drug Administration regulations; 
standards of the International Council for Harmonisation Guideline for Good Clinical Practice (E6); 
Institutional Review Board determinations; all applicable in-country, state, and local laws and regulations; 
and other applicable requirements (e.g., US National Institutes of Health, Division of AIDS) and 
institutional policies. 
 
 
 
 
 
 
        
 
 
 
 
 
 
 
 
Signature of Investigator of Record 
  
 
 
Date 
 
 
 
 
 
 
 
 
 
 
Name of Investigator of Record  
 
(printed) 
 
 
 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 7 of 106 
28 April 2022 
IMPAACT 2021  
Randomized Phase I/II Study of the Safety and Immunogenicity of a Single Dose 
of the Recombinant Live-Attenuated Respiratory Syncytial Virus (RSV) Vaccines 
RSV ΔNS2/Δ1313/I1314L, RSV 6120/ΔNS2/1030s, RSV 276 or Placebo, Delivered 
as Nose Drops to RSV-Seronegative Children 6 to 24 Months of Age 
 
ABBREVIATIONS AND ACRONYMS 
 
ACIP 
Advisory Committee on Immunization Practices (CDC) 
AE 
adverse event  
AGM 
African green monkey 
AIDS 
acquired immunodeficiency syndrome 
ANOVA 
analysis of variance 
ARI 
 
acute respiratory illness 
BSC 
 
biological safety cabinet 
cDNA 
complementary deoxyribonucleic acid 
cGMP 
current good manufacturing practice 
CFR 
Code of Federal Regulations 
CI 
confidence interval 
CIR 
Center for Immunization Research 
COVID-19 
coronavirus disease 2019  
cp 
cold-passaged  
CRADA 
Cooperative Research and Development Agreement 
CRL 
Charles River Laboratories 
CRPMC 
Clinical Research Products Management Center 
CSO 
Clinical Safety Office 
CTM 
clinical trial material 
DAERS 
DAIDS Adverse Experience Reporting System 
DAIDS 
Division of AIDS  
DAIDS PRO 
Division of AIDS Protocol Registration Office 
DC 
discontinuation 
DCR 
Division of Clinical Research 
DHHS 
Department of Health and Human Services 
DIR 
NIAID Division of Intramural Research 
DMC 
Data Management Center 
DMEM 
Dulbecco’s Modified Eagle Medium 
DMID 
Division of Microbiology and Infectious Diseases 
DNA 
deoxyribonucleic acid 
DSMB 
Data and Safety Monitoring Board 
EAE 
Expedited Adverse Event 
eCRF  
electronic case report form 
EENT 
ears, eyes, nose, throat 
ELISA 
enzyme-linked immunosorbent assay 
EMA 
European Medicines Agency 
F protein 
fusion protein (of RSV) 
FDA 
Food and Drug Administration 
FDAAA 
Food and Drug Administration Amendments Act of 2007 
FSTRF 
Frontier Science & Technology Research Foundation, Inc. 
GCP 
good clinical practice 
GMP 
good manufacturing practice 
GMT 
geometric mean peak titer 
HEENT 
head, ears, eyes, nose, throat 
HIPAA 
Health Insurance Portability and Accountability Act 

 
IMPAACT 2021, FINAL Version 3.0 
Page 8 of 106 
28 April 2022 
HIV 
Human Immunodeficiency Virus 
HJF 
Henry M. Jackson Foundation for the Advancement of Military Medicine 
HVTN 
HIV Vaccine Trials Network 
IBC 
Institutional Biosafety Committee 
ICF 
informed consent form 
ICH 
International Conference on Harmonisation 
ICU 
intensive care unit 
IgA, IgG, IgE immunoglobulin A, G, E 
IMPAACT 
International Maternal Pediatric Adolescent AIDS Clinical Trials Network 
IND 
investigational new drug 
IoR 
Investigator of Record  
IRB  
Institutional Review Board 
JHSPH 
Johns Hopkins Bloomberg School of Public Health 
JHU 
Johns Hopkins University 
LDMS 
Laboratory Data Management System 
LID 
Laboratory of Infectious Diseases 
LPC 
Laboratory Processing Chart 
LRI 
lower respiratory illness 
LRT 
lower respiratory tract 
MAARI 
medically attended acute respiratory illness 
MAALRI 
medically attended acute lower respiratory illness 
mAb 
monoclonal antibody 
MOG 
IMPAACT Management Oversight Group 
MOP 
Manual of Procedures 
MPT 
 
median peak titers  
mRNA 
messenger Ribonucleic Acid 
NHP 
nonhuman primate 
NIAID 
National Institute of Allergy and Infectious Diseases 
NIAID CRMS NIAID Clinical Research Management System 
NICHD 
National Institute of Child Health and Human Development 
NIH 
National Institutes of Health 
NIMH 
National Institute of Mental Health 
NP 
nasopharyngeal 
NS 
nasal swab 
nt 
nucleotide 
NW 
nasal wash 
OHRP 
Office for Human Research Protections 
ORF 
open reading frame 
OTC 
over-the-counter 
PCR 
polymerase chain reaction 
PE 
physical exam 
PFU 
plaque-forming unit 
PHACS  
Pediatric HIV/AIDS Cohort Study 
PID 
participant identification number 
PMTCT 
prevention of mother-to-child HIV transmission 
PRNT 
plaque reduction neutralization titer 
PSRT 
Protocol Safety Review Team 
r 
recombinant 
RE 
regulatory entity 
RNA 
ribonucleic acid 
RT-PCR 
reverse transcription polymerase chain reaction 
RSC 
Regulatory Support Center 
RSV 
respiratory syncytial virus 

 
IMPAACT 2021, FINAL Version 3.0 
Page 9 of 106 
28 April 2022 
RSV-MAARI  RSV-associated medically attended acute respiratory illness 
SAE 
Serious Adverse Event 
SAP 
Statistical Analysis Plan 
SARS-CoV-2 severe acute respiratory syndrome coronavirus 2 
SD 
standard deviation 
SDAC 
Statistical & Data Analysis Center, Harvard School of Public Health 
SDMC 
Statistical and Data Management Center 
SES 
Study Enrollment System 
SFM 
serum-free medium 
SID 
Study Identification Number 
sIRB  
single Institutional Review Board 
SMARTT  
Surveillance Monitoring for ART Toxicities  
SPDSMP 
Study Progress, Data, and Safety Monitoring Plan 
SOP 
standard operating procedure 
SPG 
sucrose-phosphate-glutamate buffer 
SUSAR 
Serious and Unexpected Suspected Adverse Reaction 
TL 
tracheal lavage  
URI 
upper respiratory illness 
URT 
upper respiratory tract 
US 
United States 
USP 
United States Pharmacopeia 
VAR 
vaccine administration record 
wt 
 
wild-type 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 10 of 106 
28 April 2022 
IMPAACT 2021 
Randomized Phase I/II Study of the Safety and Immunogenicity of a Single Dose 
of the Recombinant Live-Attenuated Respiratory Syncytial Virus (RSV) Vaccines 
RSV ΔNS2/Δ1313/I1314L, RSV 6120/ΔNS2/1030s, RSV 276 or Placebo, Delivered 
as Nose Drops to RSV-Seronegative Children 6 to 24 Months of Age 
 
PROTOCOL TEAM ROSTER 
 
Protocol Chairs 
Coleen Cunningham, MD  
University of California, Irvine 
333 City Blvd West, Suite 800 
Orange, CA, 92868 
Phone: 714-456-8470 
Email: ckcunnin@uci.edu 
 
Ruth Karron, MD 
Center for Immunization Research (CIR)  
Johns Hopkins Bloomberg School of Public 
Health (JHSPH)  
624 N. Broadway, Room 217  
Baltimore, MD 21205  
Phone: 410-614-0319  
Email: rkarron@jhu.edu 
 
Protocol Vice Chair 
Elizabeth (Betsy) J. McFarland, MD  
Children’s Hospital Colorado Pediatric 
Infectious Diseases, Box B055  
13123 East 16th Ave.  
Aurora, CO 80045  
Phone: 720-777-1966 
Email: betsy.mcfarland@cuanschutz.edu  
 
Clinical Research Managers 
Charlotte Perlowski, MSPH 
IMPAACT Operations Center 
FHI 360 
359 Blackwell Street, Suite 200 
Durham, NC 27701 
Phone: 919-321-3581 
Email: cperlowski@fhi360.org 
 
Jennifer Libous, MS, CCRP 
IMPAACT Operations Center 
FHI 360 
1825 Connecticut Ave. NW 
Washington, DC 20009 
Phone: 202-884-8131  
Email: jlibous@fhi360.org 
 
Haley Brozik, MSc 
IMPAACT Operations Center 
FHI 360 
359 Blackwell Street, Suite 200 
Durham, NC 27701 
Phone: 919-321-3922 
Email: hbrozik@fhi360.org  
 
NIAID Medical Officers 
Dwight Yin, MD, PhD, MPH 
Maternal Adolescent and Pediatric Research 
Branch, Prevention Sciences Program  
DAIDS/NIAID/NIH  
5601 Fishers Lane, Room 8B37, MSC 9831  
Rockville, MD 20852  
Phone: 301-761-5006  
Email: dwight.yin@nih.gov 
 
Patrick Jean-Philippe, MD  
DAIDS/NIAID/NIH 
Maternal, Adolescent and Pediatric Research 
Branch, Prevention Sciences Program  
5601 Fishers Lane, Room 8B21 
Rockville, MD 20852 
Phone: 240-292-4790  
Email: jeanphilippep@niaid.nih.gov   
 
NICHD Medical Officer 
Jack Moye, Jr., MD 
Eunice Kennedy Shriver National Institute of 
Child Health & Human Development 
National Institutes of Health,  
DHHS Bldg. 6710B Rm. 2130 MSC 7002 
6710B Rockledge Drive  
Bethesda, MD 20817 
Phone: 301-594-8624 
Email: john.moye@nih.hhs.gov 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 11 of 106 
28 April 2022 
DMID Program Officer 
Sonnie Kim 
DMID/NIAID/NIH 
Respiratory Diseases Branch 
Influenza, SARS, and Other Respiratory 
Diseases Section 
5601 Fishers Lane, Room 8E12 
Rockville, MD 20852 
Phone: 240-627-3287 
Email: sonnie.kim@nih.gov 
 
Protocol Pharmacist 
Kelly Colsh, PharmD 
DAIDS/NIAID/NIH 
5601 Fishers Lane, Room 9D38 
Rockville, MD 20852 
Phone: 240-669-5721 
Email: kelly.colsh@nih.gov 
 
Site-Based Pharmacist 
Vivian Rexroad, PharmD 
Investigational Drug Service Pharmacy 
Carnegie 180, Johns Hopkins Hospital 
600 North Wolfe St. 
Baltimore, MD 21287-6180 
Phone: 410-955-4505 
Email: vrexroa@jhmi.edu 
 
Clinical Investigator 
Emmanuel B. Walter, Jr., MD, MPH 
Duke Vaccine and Trials Unit 
2608 Erwin Road, Suite 210  
Durham, NC 27705  
Phone: 919-620-5374 
Email: chip.walter@duke.edu  
 
Scientific Investigators 
Ursula Buchholz, D.V.M., PhD  
Laboratory of Infectious Diseases (LID), 
National Institute of Allergy and Infectious 
Diseases (NIAID),  
NIH Building 50, Room 6503  
50 South Dr., MSC 8007  
Bethesda, MD 20892  
Phone: 301-594-1533  
Email: ubuchholz@niaid.nih.gov 
 
Peter Collins, PhD  
LID, NIAID, NIH  
Building 50, Room 6517  
50 South Dr., MSC 8007  
Bethesda, MD 20892  
Phone: 240-669-5917  
Email: pcollins@niaid.nih.gov 
 
Protocol Statisticians 
Mark Giganti, PhD 
Center for Biostatistics in AIDS Research 
Harvard TH Chan School of Public Health 
651 Huntington Avenue 
Boston, MA 02115 
Phone: 617-432-3233 
Email: mgiganti@sdac.harvard.edu 
 
Rachel Ketchum, SM 
Center for Biostatistics in AIDS Research  
Harvard TH Chan School of Public Health  
651 Huntington Avenue  
Boston, MA 02115  
Phone: 617-432-2899 
Email: rketchum@sdac.harvard.edu 
 
Protocol Data Managers 
Benjamin Johnston, BS 
Frontier Science Foundation 
4033 Maple Rd.  
Amherst, NY 14226-1056  
Phone: 716-834-0900 x7407  
Email: johnston@frontierscience.org  
 
Jared Kneebone, PhD 
Frontier Science Foundation 
4033 Maple Rd. 
Amherst, NY 14226-1056 
Phone: 716-834-0900 x7263 
Email: kneebone@frontierscience.org 
 
Protocol Laboratory Data Manager 
Frederic Bone 
Laboratory Data Manager 
Frontier Science Foundation 
4033 Maple Road 
Amherst, NY 14226 
Phone: 716-834-0900 ext. 7306 
Email: bone@frontierscience.org  

 
IMPAACT 2021, FINAL Version 3.0 
Page 12 of 106 
28 April 2022 
Laboratory Center Representatives 
Nicole Tobin, MD 
University of California Los Angeles 
MacDonald Research Laboratory  
675 Charles E. Young Drive South 
Los Angeles, CA 90095 
Phone: (310) 825-7708 
Email: ntobin@milabcentral.org 
 
Sam Yi 
IMPAACT Laboratory Center 
University of California Los Angeles 
10990 Wilshire Blvd., Suite 260 
Los Angeles, CA 90024 
Phone: 323-806-8836 
Email: syi@milabcentral.org 
 
Protocol Laboratory Technologist 
Paul Harding, MS 
Pediatric Infectious Diseases  
University of Colorado Denver  
Mail Stop 8604, Building P15  
12700 East 19th Ave., Room 11460-A  
Aurora, CO 80045  
Phone: 303-724-3404 
Email: paul.harding@ucdenver.edu 
 
IMPAACT Community Program Associate 
Marcus Bolton, MEd 
IMPAACT Operations Center 
FHI 360 
359 Blackwell St., Suite 200 
Durham, NC 22701 
Phone: (919) 544-7040 x11678 
Email: mbolton@fhi360.org 
 
Westat Clinical Research Associate  
Aundria Charles, BSN, CCRP  
Westat, Inc. 
1441 W. Montgomery Ave. 
Rockville, MD 20850 
 
Phone: 240-453-2758  
Email: AundriaCharles@westat.com  
 
JHU CIR Laboratory Representatives 
Jennifer Oliva, MS 
Center for Immunization Research 
Johns Hopkins University 
615 N. Wolfe Street, Room E5416 
Baltimore, MD 21205 
Phone: (410) 955-7230 
Email: jenn@jhu.edu; CIRLab@jhu.edu 
  
Kimberli Wanionek, MS 
Center for Immunization Research 
Johns Hopkins University 
615 N. Wolfe Street, Room E5416 
Baltimore, MD 21205 
Phone: (410) 955-7230  
Email: kwanion1@jhu.edu; CIRLab@jhu.edu 

 
IMPAACT 2021, FINAL Version 3.0 
Page 13 of 106 
28 April 2022 
STUDY SITE ROSTER 
 
Site 4001, Lurie Children’s Hospital of Chicago 
Ellen Chadwick, MD 
Ann & Robert H. Lurie Children's Hospital of 
Chicago 
225 E. Chicago Ave 
Chicago, IL 60611 
Phone: 312-227-4080 
Email: egchadwick@luriechildrens.org 
 
Site 4601, University of California San Diego 
Stephen Spector, MD 
9500 Gilman Drive 
Stein Clinical Research Building 
Room 430, Mail Code 0672 
La Jolla, CA 92093 
Phone: 858-534-7361 
Email: saspector@ucsd.edu  
 
Site 5013, Jacobi Medical Center 
Andrew Wiznia, MD 
Jacobi Medical Center 
1400 Pelham Parkway South 
JACP room 5c15, Building #5 
Bronx, NY 10461 
Phone: 718-918-4664 
Email: andrew.wiznia@einstein.yu.edu  
 
Site 5030, Emory University School of Medicine  
Andres Camacho-Gonzalez, MD, MSc  
Emory University 
2015 Uppergate Drive 
Atlanta, GA 30322 
Phone: 404-727-5642 
Email: acamac2@emory.edu  
 
Evan Anderson, MD 
Emory University 
2015 Uppergate Drive 
Atlanta, GA 30322 
Phone: 404-727-1746 
Email: evanderson@emory.edu 
 
Site 5040, SUNY Stony Brook 
Sharon Nachman, MD 
Stony Brook University Hospital 
HSC T-11 RM 060 
Department of Pediatric Infectious Disease 
Stony Brook, NY 11794-8111 
Phone: 631-444-7692 
Email: Sharon.Nachman@stonybrookmedicine.edu  
 
Site 5048, University of Southern California 
Mikhaela Cielo, MD 
Keck School of Medicine of USC 
HSA 10220, Bldg A10N 
Los Angeles, CA 90089 
Phone: 323-226-4726 
Email: mikhaela.cielo@usc.edu  
 
Site 5052, University of Colorado Denver 
Elizabeth (Betsy) J. McFarland, MD  
Children’s Hospital Colorado  
Pediatric Infectious Diseases, Box B055  
13123 East 16th Ave.  
Aurora, CO 80045  
Phone: 720-777-1966 
Email: betsy.mcfarland@cuanschutz.edu  
 
Site 5083, Rush University/Cook County 
Hospital 
Mariam Aziz, MD 
Rush University Medical Center 
600 South Paulina St., Suite 140-142 
Chicago, IL 60612 
Phone: 312-942-4265 
Email: mariam_aziz@rush.edu  
 
Site 5112, David Geffen School of Medicine at 
UCLA 
Jaime Deville, MD 
University of California, Los Angeles 
Department of Pediatrics  
Division of Infectious Diseases 
10833 Le Conte Ave., MDCC 22-442 
Los Angeles, CA 90095 
Phone: 310-825-9660 
Email: jdeville@mednet.ucla.edu  
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 14 of 106 
28 April 2022 
Site 5128, Baylor College of Medicine/Texas 
Children’s Hospital 
Mary Paul, MD 
Texas Children's Hospital 
1102 Bates Street, Suite 630 
Houston, TX 77030 
Phone: 832-822-1038 
Email: mepaul@texaschildrens.org  
 
Site 30344, Saint Louis Center for Vaccine 
Development 
Sharon Frey, MD  
Edward A. Doisy Research Center  
1100 S. Grand Boulevard, 1st Floor 
St. Louis, MO 63104 
Phone: 314-977-9032  
Email: sharon.frey@health.slu.edu 
 
Site 32029, Johns Hopkins University Center for 
Immunization Research (JHU CIR) CRS 
Ruth Karron, MD 
Center for Immunization Research  
Johns Hopkins Bloomberg School of Public 
Health (JHSPH)  
624 N. Broadway, Room 217  
Baltimore, MD 21205  
Phone: 410-614-0319  
Email: rkarron@jhu.edu 
 
Site 32014, Duke Vaccine and Trials Unit 
Emmanuel B. Walter, Jr., MD, MPH 
Duke Vaccine and Trials Unit 
2608 Erwin Road, Suite 210  
Durham, NC 27705  
Phone: 919-620-5374 
Email: chip.walter@duke.edu 
 
Site 32015, Sealy Institute for Vaccine Sciences 
Clinical Trials Program at University of Texas 
Medical Branch 
Richard Rupp, MD 
UTMB Children’s Health Center 
400 Harborside Drive 
Galveston, TX 77550 
Phone: 409-772-3695 
Email: rrupp@utmb.edu  
 
Site 32016, University of Maryland School of 
Medicine Center for Vaccine Development 
James Campbell, MD, MS 
655 West Baltimore Street 
Baltimore, Maryland 21201-1559  
Phone: 410-706-5328 
Email: jcampbel@medicine.umaryland.edu 
 
Site 32017, The Children’s Mercy Hospital 
James Christopher Day, MD  
Children's Mercy Kansas City 
2401 Gillham Road 
Kansas City, MO 64108 
Phone: 816-234-3207 
Email: ccday@cmh.edu 
 
Jennifer Schuster, MD 
Children's Mercy Kansas City 
2401 Gillham Road 
Kansas City, MO 64108 
Phone: 816-234-3061 
Email: jeschuster@cmh.edu 
 
Site 32018, Gamble Center for Clinical Studies 
at Cincinnati Children’s Hospital Medical 
Center 
Robert W. Frenck, Jr., MD 
Division of Infectious Diseases 
Cincinnati Children’s Hospital Medical Center 
3333 Burnet Avenue 
Cincinnati, OH 45229 
Phone: 513-636-4463 
Email: robert.frenck@cchmc.org

 
IMPAACT 2021, FINAL Version 3.0 
Page 15 of 106 
28 April 2022 
IMPAACT 2021 
Randomized Phase I/II Study of the Safety and Immunogenicity of a Single Dose 
of the Recombinant Live-Attenuated Respiratory Syncytial Virus (RSV) Vaccines 
RSV ΔNS2/Δ1313/I1314L, RSV 6120/ΔNS2/1030s, RSV 276 or Placebo, Delivered 
as Nose Drops to RSV-Seronegative Children 6 to 24 Months of Age 
 
SCHEMA 
 
Purpose: 
To assess whether the live-attenuated RSV vaccine candidates RSV 
ΔNS2/Δ1313/I1314L, RSV 6120/ΔNS2/1030s, and RSV 276 will each be 
safe and immunogenic in RSV-seronegative recipients.  
 
Design: 
A double-blind, randomized, placebo-controlled study to evaluate the safety 
and immunogenicity of the vaccines in RSV-seronegative infants and 
children 6 to 24 months of age (referred to throughout the protocol as 
children). As with protocol V2.0, participants in protocol V3.0 will be 
randomized equally to receive RSV ΔNS2/Δ1313/I1314L vaccine, RSV 
6120/ΔNS2/1030s vaccine, or placebo (a third vaccine, RSV 276 included 
under protocol V1.0 is not included under protocol V2.0 or V3.0). 
Participants will be enrolled in the study outside the time during which wild-
type (wt) RSV circulates in the community at each study site. All participants 
will remain on study until they complete the Post-RSV Season Visit between 
April 1st and April 30th in the calendar year following study product 
administration.  
 
Study Population: 
Healthy RSV-seronegative* children ≥6 months (180 days) at the time of 
screening to <25 months (750 days) of age at the time of enrollment 
 
* Throughout the protocol and informed consent documents, seronegativity 
refers to RSV antibody status, which is defined as a serum RSV-neutralizing 
antibody titer <1:40. 
Sample Size: 
Approximately 130, including approximately 40 each in the placebo and two 
candidate vaccine arms open under protocol V2.0 and V3.0, as well as all 
participants previously randomized to receive RSV 276 under protocol V1.0 
prior to closure of this arm  
 
Study Product: 
As with protocol V2.0, under protocol V3.0, eligible RSV-seronegative 
children will receive a single dose of RSV ΔNS2/Δ1313/I1314L vaccine, 
RSV 6120/ΔNS2/1030s vaccine, or placebo intranasally at enrollment. 
 
 
         
 
 
 
 
 
 
 
 
~N 
Product 
Dose 
40 
RSV ΔNS2/Δ1313/I1314L 
Vaccine 
106 
PFU** 
40 
RSV 6120/ΔNS2/1030s vaccine 
105 
PFU** 
10 
RSV 276 Vaccine  
(enrollment closed under 
protocol V2.0 and V3.0) 
105 
PFU** 
40 
Placebo 
0 
**plaque-forming units (PFU) 

 
IMPAACT 2021, FINAL Version 3.0 
Page 16 of 106 
28 April 2022 
Study Duration: 
Up to approximately 58 months total, as described below. All participants 
will be followed through April of the year following their enrollment. 
Therefore, expected length of follow-up for a given participant is between 4 
and 15 months depending on time of enrollment. Given the study did not 
fully accrue in the first enrollment season (2019), enrollment was paused 
during the second enrollment season (2020) due to COVID-19, and no sites 
were able to resume enrollment during the third enrollment season (2021), 
enrollment will be extended into a fourth enrollment season (e.g., 2022), 
resulting in a total enrollment period of approximately 42 months and total 
study duration of approximately 46 months. 
 
If a fifth enrollment season (e.g., 2023) is required and approved, the total 
enrollment period will be approximately 54 months and the total study 
duration approximately 58 months. 
 
Primary Objectives 
1. Safety: To estimate and compare (each vaccine group to placebo) the frequency and severity of 
adverse events (AEs) following study product administration (Day 0) through Day 56 
2. Immunogenicity: To estimate and compare (between the vaccine groups and to the benchmark of 
70%) the percentage of vaccinees having a ≥4-fold rise in serum RSV-neutralizing antibodies at 
the Day 56 Visit  
 
Secondary Objectives 
1. Immunogenicity: To estimate and compare (between the vaccine groups) the percentage of 
vaccinees with a ≥4-fold rise in serum IgG antibody to RSV F protein (RSV F IgG) at the Day 56 
Visit 
2. Immunogenicity: To estimate and compare (between the vaccine groups) the titers of serum RSV 
F IgG and serum RSV-neutralizing antibodies at the Day 56 Visit 
3. Safety: To describe and compare the frequency and severity of RSV-associated, medically 
attended, acute respiratory illness (RSV-MAARI) and RSV-associated, medically attended, acute 
lower respiratory illness (RSV-MAALRI) in the placebo and vaccine arms during RSV season 
 
Exploratory Objectives 
1. To evaluate the association of vaccine virus shedding with adverse events: To assess the 
incidence and magnitude of vaccine virus shedding in samples collected at Illness Visits 
associated with solicited AEs on Study Days 0 through 28 and with serious AEs from Study Day 
0 through Day 56  
2. Immunogenicity – timing of maximum response: To estimate and compare serum RSV F IgG and 
serum RSV-neutralizing antibody responses at the Day 28 and 56 Visits in each vaccine group 
3. Immunogenicity – magnitude of anamnestic response: To estimate and compare (each vaccine 
group to placebo and between the vaccine groups) the titers of serum RSV F IgG and serum 
RSV-neutralizing antibodies in participants infected with wt RSV during the RSV season  
4. Immunogenicity – durability of vaccine-induced RSV antibodies: to estimate and compare 
(between the vaccine groups), the magnitude of RSV serum antibody titers in samples collected at 
the Day 56 and Post-RSV Season Visits among vaccine recipients who do not have evidence of 
RSV infection during RSV season 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 17 of 106 
28 April 2022 
IMPAACT 2021 
Randomized Phase I/II Study of the Safety and Immunogenicity of a Single Dose 
of the Recombinant Live-Attenuated Respiratory Syncytial Virus (RSV) Vaccines 
RSV ΔNS2/Δ1313/I1314L, RSV 6120/ΔNS2/1030s, RSV 276 or Placebo, Delivered 
as Nose Drops to RSV-Seronegative Children 6 to 24 Months of Age 
 
Figure 1: Study Overview 
Panel A: Randomization Scheme 
 
 
 
Panel B: Study Procedures (All Study Product Arms) 
  
  

 
IMPAACT 2021, FINAL Version 3.0 
Page 18 of 106 
28 April 2022 
1 
INTRODUCTION  
 
1.1 
Overview 
 
Human respiratory syncytial virus (RSV) is the most common viral cause of serious acute lower 
respiratory illness (LRI) in infants and children under 5 years of age worldwide (1). There is 
broad consensus that a vaccine is needed. Attenuated live virus vaccines are a promising strategy 
for RSV since they have not been associated with vaccine enhanced disease (2) and they have the 
potential of inducing a spectrum of immune responses similar to responses induced by wild-type 
infection (3). This protocol is part of a multi-year development plan aimed at identifying a 
candidate RSV vaccine that is sufficiently attenuated but still immunogenic. 
 
One attenuation strategy that has shown great promise is the deletion of the viral interferon 
antagonist NS2, resulting in an NS2 deletion mutant. Each of the two most promising NS2 
deletion candidates, RSV ∆NS2/∆1313/I1314L and RSV 6120/∆NS2/1030s, contains a second 
attenuating element in addition to the NS2 deletion. As the second element, RSV 
∆NS2/∆1313/I1314L contains a deletion ∆1313 of a single codon of the L polymerase open 
reading frame (ORF), stabilized by an adjacent mutation I1314L. RSV 6120/∆NS2/1030s is 
identical to RSV ∆NS2/∆1313/I1314L, but was made to be slightly less attenuated by replacing 
the ∆1313/I1314 mutations by the 1030s mutation, consisting of 1321K(AAA) and 1313S(TCA) 
in the L gene. Both ∆NS2 vaccine candidates are attenuated and moderately temperature 
sensitive. In a Phase I trial (NCT01893554), a single intranasal dose of 106 PFU of RSV 
∆NS2/∆1313/I1314L was well tolerated and immunogenic in RSV-seronegative children 6-24 
months of age (20 vaccine recipients, 10 placebo recipients). 80% and 90% of recipients shed 
virus detected by culture and RT-qPCR, respectively (geometric mean peak titers (GMT) 1.8 
log10 PFU/mL; 3.5 log10 copies/mL). Moreover, 85% and 80% had ≥4-fold increases in RSV F 
IgG and RSV-neutralizing serum antibody titers, respectively. The serum antibody response was 
durable over the RSV surveillance season, and the vaccine primed for a strong anamnestic 
response to wild-type RSV. There was no evidence of excess respiratory illness associated with 
receipt of a 106 dose of RSV ∆NS2/∆1313/I1314L. [(4), manuscript in preparation].  
 
RSV 6120/∆NS2/1030s was also well-tolerated and highly restricted in replication in 12- to 59- 
month-old RSV seropositive children (10 vaccinees and 5 placebo recipients) and is currently 
being evaluated at a 105 dose in RSV-seronegative children 6-24 months of age. To date, 23 RSV-
seronegative children have been enrolled in this study; information about study allocation, 
vaccine virus shedding, and tolerability is pending. 
 
Another very promising strategy is based on the deletion of a large section of the open reading 
frame encoding the RSV RNA regulatory protein M2-2 from the RSV genome. Deletion of M2-2 
increases viral mRNA production, and reduces viral RNA replication (5). The increase in mRNA 
production results in increased synthesis of viral antigen, with the potential for increased 
immunogenicity, and the decreased RNA replication results in delayed assembly of new virus 
particles, and in attenuation. The first candidate RSV vaccine using this strategy, MEDI/ΔM2-2, 
was studied sequentially in adults, seropositive children, and then seronegative infants and 
children (age 6 to 24 months) (6). This study found that the vaccine had excellent 
immunogenicity despite very low viral replication in seronegative infants and children: at a dose 
of 105 PFU, only 60% of RSV-seronegative vaccinees shed vaccine virus (mean peak titer by 
culture from NW samples, 1.5 log10 PFU/mL), yet 95% of vaccinees had ≥4-fold increases in 
RSV-neutralizing serum antibody titers, and substantial serum RSV-neutralizing antibody 
responses were achieved (GMT=1:97). RSV MEDI/∆M2-2 thus had a very promising phenotype, 
but this vaccine was evaluated as part of a Collaborative Research and Development Agreement 

 
IMPAACT 2021, FINAL Version 3.0 
Page 19 of 106 
28 April 2022 
(CRADA) with Medimmune, LLC, that has been terminated, and this material was not available 
for further study. Therefore, a similar virus, RSV 276, was generated to replace MEDI/∆M2-2, as 
described in greater detail below.  
 
Based on infectivity, safety, and immunogenicity data to date, these three candidate vaccines—
RSV ∆NS2/∆1313/I1314L, RSV 6120/∆NS2/1030s, and RSV 276—appear to be the strongest 
candidates to move into expanded Phase I/II trial (IMPAACT 2021) for a further evaluation of 
vaccine safety and immunogenicity. Each candidate contains a large deletion mutation, which 
effectively reduces the potential for de-attenuation, an important concern for a live-attenuated 
vaccine. This expanded Phase I/II study will evaluate safety, and immunogenicity of these three 
lead candidates. As a secondary objective, we will assess the rates of RSV-medically attended 
acute respiratory illness (MAARI) and RSV-medically attended acute lower respiratory illness 
(MAALRI) in vaccine recipients and placebo recipients during the RSV season following receipt 
of study product (secondary safety outcome measure).  
 
Table 1 includes an overview of recent RSV studies involving these and related candidates. The 
candidates used in IMPAACT 2021 are further described in Table 2. 
 
Table 1: Overview of recent RSV vaccine candidates with M2-2 or NS2 deletiona 
 
IMPAACT
/CIR 
Protocol 
Vaccine 
name 
Attenuating mutations, key features 
Expected effect 
Study status 
CIR  275 
MEDI/ 
∆M2-2 
• Deletion of the RSV RNA regulatory 
M2-2 protein 
• Attenuation 
• Increased 
immunogenicity 
 
• Achieved target 
accrual (n=30)  
• Highly attenuated 
• Highly immunogenic 
(6) 
2000/291 
LID 
∆M2-2 
• Deletion of the RSV RNA regulatory 
M2-2 protein 
• Differences between LID/∆M2-2 and 
MEDI/∆M2-2:  
1. Deletion of 112 nt of the 3’ SH 
noncoding region 
2. Slightly different design of M2-2 
deletion 
3. 19 silent nucleotide changes and two 
non-synonymous changes (in NS2, 
N) 
4. Except for a single amino acid 
difference in NS2 and N, same amino 
acid sequence as MEDI/∆M2-2 
• Attenuation 
• Increased 
immunogenicity 
 
• Closed to accrual 
(n=29)  
• Peak viral titers in NW 
higher than expected,  
exceeded MEDI/∆M2-
2 (7) 
2011/311 
LID 
∆M2-2 
1030s 
• Deletion of the RSV RNA regulatory 
M2-2 protein  
• Differences to MEDI/∆M2-2 as 
described for LID/∆M2-2 above, plus: 
• genetically stable “1030s” attenuating 
point mutation [Y1321K(AAA) and 
S1313(TCA) mutation in L] 
• Attenuation 
• Temperature 
sensitivity 
• Increased 
immunogenicity 
• Achieved target 
accrual (n=33)  
• Highly immunogenic, 
attenuated, no safety 
signal 

 
IMPAACT 2021, FINAL Version 3.0 
Page 20 of 106 
28 April 2022 
IMPAACT
/CIR 
Protocol 
Vaccine 
name 
Attenuating mutations, key features 
Expected effect 
Study status 
2012/312 
LID cp 
∆M2-2 
• Deletion of the RSV RNA regulatory 
M2-2 protein 
• Differences to MEDI/∆M2-2 as 
described for LID/∆M2-2 above, plus: 
• five point mutations (derived from cold-
passaged RSV) in the RSV 
nucleoprotein, fusion protein, and 
polymerase protein 
• Attenuation 
(increased by 
addition of cp 
mutations) 
• Increased 
immunogenicity 
• Closed to accrual 
(n = 17)  
• Over-attenuated 
2013/313 
D46/NS
2/N/ 
∆M2-2-
HindIII 
• Deletion of the RSV RNA regulatory 
M2-2 protein; design based on 
MEDI/∆M2-2. 
• Contains complete 3’ SH noncoding 
region that is deleted in “LID” versions;  
• Differences between D46/NS2/N/ 
∆M2-2-HindIII and MEDI/∆M2-2: 19 
silent nucleotide changes. 
• Same amino acid sequence as 
MEDI/∆M2-2 
• Attenuation 
• Increased 
immunogenicity 
• Achieved target 
accrual (n=32) 
• Analysis finalized in 
February 2019 
2018/321 
 
RSV 276 • Deletion of the RSV RNA regulatory 
M2-2 protein; design based on 
MEDI/∆M2-2. 
• Contains the SH noncoding region that 
is deleted in “LID” versions; 
• RSV 276 replaces MEDI/∆M2-2, 
differing by two nucleotides in the 5’ 
noncoding region of the M2 gene (nt 
8198/99; GC in MEDI/∆M2-2; CG in 
RSV 276), and by two noncoding 
changes (A1937G; T13900C)  
• Attenuation 
• Increased 
immunogenicity 
• Closed to accrual 
(n=65) 
• RSV 276: associated 
with higher rate of 
solicited AEs 
• RSV ∆NS2/∆1313/ 
I1314L: favorable 
safety profile 
 
RSV 
∆NS2/ 
∆1313/I1
314L 
• Vaccine candidate with deletion of the 
RSV interferon antagonist NS2 (ΔNS2) 
included for comparison 
• Deletion of codon 1313 of the 
polymerase gene (Δ1313), codon 1314 
was genetically stabilized (I1314L) 
• Attenuation 
• Temperature 
sensitivity 
• Increased 
immunogenicity 
aGenomic position numbering is in reference to biological wt RSV strain A2 (Genbank accession number M74568), which is 
15,222 nt in length. Thus, deletions or insertions in the recombinant viruses do not change the sequence numbering of the 
remaining nucleotides.  
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 21 of 106 
28 April 2022 
Table 2: Overview of RSV vaccine candidates with NS2 or M2-2 deletion to be 
studied in IMPAACT 2021 
 
Vaccine name Attenuating mutations, key features 
Expected effect 
RSV 276 
• Deletion of the RSV RNA regulatory M2-2 protein (ΔM2-2); 
design based on MEDI/∆M2-2. 
• Contains the SH noncoding region that is deleted in “LID” 
versions; 
• RSV 276 is similar to MEDI/∆M2-2, differing by two 
nucleotides in the 5’ noncoding region of the M2 gene (nt 
8198/99; GC in MEDI/∆M2-2; CG in RSV 276), and by two 
noncoding changes in N and L (A1937G; T13900C)  
• Attenuation 
• Increased immunogenicity 
RSV ∆NS2/ 
∆1313/I1314L 
• Deletion of the RSV interferon antagonist NS2 (ΔNS2) 
• Deletion of codon 1313 of the polymerase gene (Δ1313), 
Codon 1314 was genetically stabilized (I1314L) 
• Attenuation 
• Temperature sensitivity 
• Increased immunogenicity 
RSV 
6120/∆NS2/ 
1030s 
• Deletion of the RSV interferon antagonist NS2 (ΔNS2) 
• genetically stable “1030s” attenuating point mutation 
[Y1321K(AAA) and S1313(TCA) mutation in L] 
• Slightly less attenuated than 
RSV ∆NS2/∆1313/I1314L 
• Temperature sensitivity 
• Increased immunogenicity 
 
In IMPAACT 2021, the lead candidates from each attenuation strategy, RSV 
∆NS2/∆1313/I1314L, RSV 6120/ΔNS2/1030s, and RSV 276, will be evaluated side-by-side. A 
placebo group equal in size to each vaccine group is included because of the high background of 
respiratory/febrile illness among RSV-seronegative children in this age group. 
 
It is hoped that all candidates will:  
• 
be safe, and  
• 
result in at least 70% of the population of vaccine recipients having a ≥4-fold rise in serum 
RSV-neutralizing antibody titers from pre-study product administration to the Day 56 
Visit after study product administration 
 
However, one or more of these vaccine candidates may have safety signals that become apparent 
only when compared to placebo recipients in this larger number of participants. The vaccine 
candidates may differ in the magnitude of antibody responses and in responses observed 
following naturally occurring RSV infection.  
 
RSV∆NS2/∆1313/I1314L was previously evaluated at both 105 PFU and 106 PFU; both doses 
were well tolerated, but only the 106 PFU dose was sufficiently infectious and immunogenic. For 
this reason, RSV∆NS2/∆1313/I1314L will only be tested at the 106 dose level. RSV 
6120/∆NS2/1030s will be evaluated and RSV 276 was evaluated (under protocol V1.0) at a dose 
of 105 PFU, the dose used in previous studies of RSV 6120/∆NS2/1030s, MEDI ∆M2-2, and RSV 
276. 
 
1.2 
Background  
 
Epidemiology, Disease Burden, and the Need for a Vaccine 
 
In the United States alone, RSV is responsible for 75,000 to 125,000 hospitalizations of infants 
yearly (8), and worldwide, RSV is responsible for at least 34 million cases of lower respiratory 
tract disease in children under 5 years, resulting in an estimated 3.4 million hospitalizations and 
66,000 to 199,000 RSV-attributable deaths each year (1). In temperate climates, annual RSV 

 
IMPAACT 2021, FINAL Version 3.0 
Page 22 of 106 
28 April 2022 
epidemics occur in late winter and early spring, and nearly all children are infected within the 
first 2 years of life.  RSV illness can range from mild upper respiratory tract illness (URI), 
including rhinitis, pharyngitis, and coryza, to severe LRI, including bronchiolitis and pneumonia. 
Beyond the acute burden of disease caused by RSV, severe RSV disease in infancy may 
predispose to reactive airways disease during childhood (9, 10). 
 
RSV is an enveloped RNA virus that is a member of the newly organized Pneumoviridae family, 
genus Orthopneumovirus (11). RSV has a single negative-sense strand RNA genome of 15.2 
kilobases encoding 10 mRNAs. Each mRNA encodes a single protein, with the exception of the 
M2 mRNA, which contains 2 overlapping open reading frames (ORFs). The 11 RSV proteins are: 
the viral RNA-binding nucleoprotein N, the phosphoprotein P, the large polymerase protein L, the 
attachment glycoprotein G, the fusion glycoprotein F, the small hydrophobic surface glycoprotein 
SH, the internal matrix protein M, the 2 nonstructural proteins NS1 and NS2, and the M2-1 and 
M2-2 proteins encoded by the M2 mRNA. The gene order is: 3’-NS1-NS2-N-P-M-SH-G-F-M2-
L-5.’ RSV transcription and genome replication take place exclusively in the cytoplasm, and 
virions form by budding from the apical plasma membrane of respiratory epithelial cells.  
 
Currently, no licensed vaccine against RSV is available, although there is broad consensus that 
such a vaccine is urgently needed and should be a global health priority. Although passive 
immunoprophylaxis with the RSV-neutralizing monoclonal antibody palivizumab (Synagis®; 
MedImmune) is available for high-risk infants, this approach is not feasible for general use. A 
formalin-inactivated vaccine against RSV was evaluated clinically in the 1960s and did not 
confer protection; instead, disease enhancement occurred at a high rate following natural 
infection of vaccinees with wt RSV (12). Studies in experimental animals established that disease 
enhancement was specific to non-replicating RSV vaccines and not seen with infectious RSV or 
replicating vaccine vectors (13, 14).   
 
Following the failure of the formalin-inactivated RSV vaccine, attempts at developing RSV 
vaccines at National Institute of Allergy and Infectious Diseases (NIAID) have focused largely on 
live-attenuated approaches (3). Importantly, over a period of over 20 years, a number of live-
attenuated investigational RSV vaccines have been evaluated in RSV-seronegative or RSV-naïve 
infants and children, and enhanced disease following wt RSV infection of vaccinees has not been 
observed (2). Apart from the absence of enhanced disease, live-attenuated RSV vaccines have a 
number of known advantages over non-replicating RSV vaccines. They can be administered 
intranasally, induce protective mucosal immunity in the respiratory tract (as well as systemic 
immunity), infect in the presence of maternally-derived RSV serum antibody, and have been well 
tolerated and immunogenic when administered to infants as young as four weeks of age (15).  
 
Human RSV has a single serotype with two antigenic subgroups, A and B. The two subgroups 
exhibit a 3- to 4-fold reciprocal difference in neutralization by polyclonal convalescent serum. 
Analysis of glycoprotein-specific responses in infants by enzyme-linked immunosorbent assay 
(ELISA) with purified F and G glycoproteins showed that the fusion proteins (F proteins) were 
50% related antigenically, and the G proteins were 7% related (16). Consistent with this level of 
antigenic relatedness, F protein expressed by a recombinant vaccinia virus was equally protective 
in cotton rats against challenge with either subgroup A or B, whereas the G protein was 13-fold 
less effective against the heterologous subgroup (17). Thus, the F protein is responsible for most 
of the observed cross-subgroup neutralization and protection, and a subgroup A vaccine virus is 
likely to induce a broad immune response against wt RSV of either subgroup. Antibodies to the F 
protein are one of the endpoints evaluated in this study. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 23 of 106 
28 April 2022 
The RSV vaccines to be evaluated in this study were derived using a recombinant 
deoxyribonucleic acid (DNA)-based technique called reverse genetics (18). This technique allows 
de novo recovery of infectious virus entirely from complementary DNA (cDNA) in a qualified 
cell substrate under defined conditions. Reverse genetics provides a means to introduce 
predetermined mutations into the RSV genome via the cDNA intermediate. Derivation of vaccine 
virus from cDNA minimizes the risk of contamination with adventitious agents and helps to keep 
the passage history brief and well documented. Once recovered, the vaccine virus is propagated in 
the same manner as a biologically derived virus. As a result of repeated passage and 
amplification, the drug substance (clinical trial material) does not contain any recombinant DNA. 
The RSV vaccine candidates to be tested under this protocol are derivatives of strain A2, 
subgroup A. 
 
Vaccine Description 
 
In previous Phase I studies in RSV-seronegative infants and children 6 to 24 months of age, the 
live-attenuated RSV strains RSV ∆NS2/∆1313/I1314L, RSV 6120/ΔNS2/1030s, and RSV 276, a 
virus that is similar to MEDI ∆M2-2, have emerged as the most promising candidates.  
 
RSV ΔNS2/Δ1313/I1314L contains two independent attenuating elements: (i) a 523 nt deletion of 
the viral interferon/apoptosis antagonist NS2 gene, and (ii) an amino acid deletion in the L protein 
(Δ1313; deletion of S1313). In addition, RSV ΔNS2/Δ1313/I1314L contains the genetically 
stabilizing mutation I1314L (19). This stabilizing mutation was included to prevent the de-
attenuating second site mutation I1314T (20). RSV 6120/∆NS2/1030s is identical to RSV 
∆NS2/∆1313/I1314L but was made to be slightly less attenuated by replacing the ∆1313/I1314 
mutations by the 1030s mutation, consisting of Y1321K(AAA) and 1313S(TCA) in the L gene. 
RSV with NS2 deletion is attenuated in animal models, including in chimpanzees (21). As shown 
in the bovine RSV/calf model (22), the deletion of an RSV interferon/apoptosis antagonist may 
increase immunogenicity. To study the attenuating effect of ∆1313 alone, a recombinant RSV 
with deletion of codon 1313 of the L gene was evaluated (RSV ∆1313). On their own, the 
deletion of codon 1313 or the 1030s mutation of the polymerase gene had a substantial 
attenuating effect on RSV. ∆1313 rendered RSV temperature sensitive (ts), with a shutoff 
temperature (TSH) of 37°C, and was strongly attenuating in mice. 1030s also induced temperature 
sensitivity, but at a TSH that was one degree higher (38°C) than that of RSV ∆1313. The 1030s 
mutation also was less attenuating than ∆1313 in the mouse model (19). 
 
MEDI/∆M2-2 was attenuated by deletion of the RNA regulatory protein M2-2 (5). MEDI/∆M2-2 
was very highly restricted, well tolerated, safe, and immunogenic in a previous study in RSV-
seronegative children and infants (6), but is not available for further study. RSV 276 was 
designed to be similar to MEDI/∆M2-2. Like MEDI/∆M2-2, RSV 276 contains a deletion of the 
RSV RNA-regulatory M2-2 protein, resulting in increased mRNA production and reduced RNA 
replication (5). Recombinant RSV with M2-2 deletion grows more slowly in vitro than wt RSV 
(5, 23). Deletion of M2-2 results in increased accumulation of intracellular viral mRNA and 
decreased accumulation of genome and antigenome (5). The increase in mRNA accumulation in 
cells infected with an M2-2-deleted RSV (∆M2-2) was accompanied by an increase in the 
expression of RSV proteins, including expression of the F and G glycoproteins, suggesting that 
M2-2 deletion mutants might be more immunogenic than wt RSV. RSV with M2-2 deletion is 
highly attenuated in pre-clinical studies (6, 23, 24). RSV 276 differs from MEDI/∆M2-2 only by 
four nucleotides: specifically, two nucleotides in the 5’ noncoding region of the M2 gene (nt 
8198/99; GC in MEDI/∆M2-2; CG in RSV 276), and two noncoding changes (A1937G in the N 
ORF; T13900C in the L ORF). It is anticipated that these four nucleotide differences between 

 
IMPAACT 2021, FINAL Version 3.0 
Page 24 of 106 
28 April 2022 
MEDI/∆M2-2 and RSV 276 will not affect replication, attenuation, safety, and immunogenicity 
in humans because two of these differences are in a non-coding region adjacent to the deletion in 
M2-2 and the other two occur in open reading frames without changing amino acid coding. 
 
RSV ∆NS2/∆1313/I1314L, RSV 6120/ΔNS2/1030s, and RSV 276 are cDNA derived live-
attenuated RSV vaccine candidates. The seed viruses were generated at the Laboratory of 
Infectious Diseases (LID), NIAID (non-GMP), and transferred to Charles River Laboratories 
[CRL; Malvern, PA; operated under cGMP (current Good Manufacturing Practice)]. The seed 
viruses passed pre-production testing (Sterility, Mycoplasma, Bacteriostasis/Fungistasis and 
testing for porcine circovirus types 1 and 2; testing performed at CRL under cGMP) and were 
accepted for manufacturing of the Drug Product under cGMP in Vero cells. The Drug Products 
are contained in sterile 2.0 mL micro tubes, each containing 0.6 mL volumes. 
 
The RSV ΔNS2/Δ1313/I1314L Drug Product is a concentrate of live recombinant RSV 
ΔNS2/Δ1313/I1314L Vero Grown Virus Vaccine (Lot RSV#006A) in OptiPro SFM with 
1X SPG (sucrose, 0.218 M; KH2PO4, 0.0038 M; K2HPO4, 0.0072 M; L-Glutamic Acid, 0.0054 
M). The Drug Product has a potency of approximately 7.3 log10 PFU/mL and is diluted to dose on 
site. 
 
The RSV 276 (Lot RSV#014A) and the RSV 6120/ΔNS2/1030s (Lot RSV#012A) Drug Products 
are concentrates of live recombinant Vero Grown Virus Vaccine in DMEM without phenol red 
with 1X SPG (sucrose, 0.218 M; KH2PO4, 0.0038 M; K2HPO4, 0.0072 M; L-Glutamic Acid, 
0.0054 M). The RSV 276 (Lot RSV#014A) Drug Product has a potency of approximately 6.2 
log10 PFU/mL, and the RSV 6120/ΔNS2/1030s (Lot RSV#012A) Drug Product has a potency of 
approximately 6.0 log10 PFU/mL. Both are diluted to dose on site. 
 
The Final Drug Products, RSV ΔNS2/Δ1313/I1314L, Lot RSV#006A, RSV 6120/ΔNS2/1030s, 
Lot RSV#012A, and RSV 276, Lot RSV#014A, passed all in-vitro and in-vivo testing required 
for viral vaccines (Detection of Inapparent Viruses in a Viral Vaccine Product, in vitro 
Tuberculosis Testing, PCR-based Reverse Transcriptase Testing, Porcine Circovirus Testing, 
Sterility, Mycoplasma, Bacteriostasis/Fungistasis, Residual DNA testing, DNA Sizing, 
Endotoxin, Determination of the Sucrose Level, pH Determination, Intact Cell Assay, 
Potency/Infectivity, Identity, Purity, Toxicology and Pharmacology testing). Sequence analysis 
confirmed that the genomic sequences of the Drug Products, Lots RSV#006A, RSV#012A, and 
RSV#014A, were identical to the cDNA that each was derived from. RSV ΔNS2/Δ1313/I1314L, 
Lot RSV#006A, RSV 6120/ΔNS2/1030s, Lot RSV#012A, and RSV 276, Lot RSV#014A, were 
released by CRL for use as investigational vaccines. 
 
1.3 
Prior Research 
 
1.3.1 
Experimental Vaccines against Respiratory Syncytial Virus 
 
Efforts have been directed toward the development of a live-attenuated RSV vaccine because of 
the advantages of live-attenuated vaccines over inactivated or subunit vaccines. These advantages 
include the ability to (i) induce the full spectrum of protective immune responses including serum 
and local antibodies as well as CD4+ and CD8+ T cells and innate immunity, (ii) infect and 
replicate in the presence of maternal antibody permitting immunization of young infants, and (iii) 
produce an acute, self-limited, attenuated infection that is well tolerated and readily eliminated 
from the respiratory tract. Another important advantage is the absence of vaccine-related 
enhanced disease, as has been confirmed in clinical studies (2). 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 25 of 106 
28 April 2022 
Several live-attenuated RSV vaccines have been evaluated in clinical trials in adult and pediatric 
populations as part of NIAID’s ongoing RSV vaccine development program (6, 15, 25-27). RSV 
∆NS2/∆1313/I1314L, RSV 6120/ΔNS2/1030s, and RSV 276 represent the lead vaccine 
candidates from these attenuation strategies. Prior to studies of RSV ΔNS2/Δ1313/I1314L and 
RSV 6120/ΔNS2/1030s, three RSV vaccine viruses with NS2 deletion (rA2cpΔNS2, 
rA2cp248/404ΔNS2, and rA2cp530/1009ΔNS2) had been evaluated in clinical studies (27). Prior 
to evaluation of RSV 276 under the present protocol, several RSV candidates with M2-2 deletion 
have been evaluated. A short summary of preclinical studies involving these vaccine candidates is 
included below, and a description of previous human experience with the prior candidates that are 
most closely related to the candidates of the present protocol can be found in Section 1.3.3.  
 
1.3.2 
Preclinical Studies 
 
1.3.2.1 Genetic Stability of RSV ΔNS2/Δ1313/I1314L and RSV 6120/ΔNS2/1030s 
 
RSV ΔNS2/Δ1313/I1314L and RSV 6120/ΔNS2/1030s are temperature sensitive, with shut-off 
temperatures for virus replication of 38ºC-39°C (RSV ΔNS2/Δ1313/I1314L) and 40°C (RSV 
6120/ΔNS2/1030s) and showing a small-plaque phenotype at 37°C and above (RSV 
ΔNS2/Δ1313/I1314L) and 38°C and above (RSV 6120/ΔNS2/1030s). In case of RSV 
ΔNS2/Δ1313/I1314L, this phenotype is associated with the deletion of a single codon of the 
polymerase ORF, codon 1313 (19, 20). To prevent a de-attenuating second-site mutation that had 
been observed in an in-vitro genetic stability stress test, the neighboring codon I1314 was 
genetically stabilized by changing it to I1314L. In further in-vitro stability stress tests, this 
I1314L change indeed stabilized the 1313 site of the RSV polymerase ORF. The genetic stability 
of RSV ΔNS2/Δ1313/I1314L was confirmed by sequence analysis of RSV ΔNS2/Δ1313/I1314L 
isolates from a previous Phase I study. This recent pediatric vaccine study showed that RSV 
ΔNS2/Δ1313/I1314L is a genetically stable RSV vaccine candidate (Karron et al., manuscript in 
preparation).  
 
The moderate temperature sensitivity of RSV 6120/ΔNS2/1030s is associated with the “1030s” 
mutation. This mutation is also genetically stabilized (19). This “1030s” mutation was included in 
the previous vaccine candidate RSV cps2. Of note, no evidence for genetic instability of the 
“1030s” site was detected in vaccine isolates obtained during a clinical study of this candidate in 
infants and children (4). 
 
1.3.2.2 Replication of RSV ΔNS2/Δ1313/I1314L and RSV 6120/ΔNS2/1030s in an in-vitro model of 
mucociliary normal human tracheal/bronchial epithelial cells 
 
Multicycle replication of experimental lots of RSV ∆NS2/∆1313/I1314L and RSV 
6120/ΔNS2/1030s was compared to that of wt RSV in a 3D mucociliary human tissue model of 
normal pseudostratified differentiated primary human tracheal/bronchial airway epithelial cells 
(EpiAirway, Mattek, Inc.), cultured in an air-liquid interface at two different temperatures (32°C 
and 37°C) to model the temperatures of the upper and lower airways RSV. Differentiated human 
airway cells represent the best available in-vitro model to predict vaccine replication. Wt RSV A2 
was included for comparison. Triplicate wells were infected at an MOI of 0.1 in 100 µl of 
medium per well. After 2 hours of adsorption, virus inoculum was gently removed, and the apical 
surfaces of the cultures were washed 3 times with 300 µL PBS. Apical washes were collected 
daily on days 1-7 post-infection to assay viral replication, snap frozen, and virus titers were 
determined by RSV immunoplaque assay on Vero cells. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 26 of 106 
28 April 2022 
Recombinant wt RSV of strain A2 replicated efficiently in these differentiated primary human 
tracheal/bronchial epithelial cells at 32°C and at 37°C. At 32°C, peak titers of about 5.6 log10 
PFU/mL of wt RSV were detected on day 6, whereas at 37°C, peak titers of about 6.1 log10 were 
reached by day 5 post-infection. At 32°C, peak titers of RSV ∆NS2/∆1313/I1314L were detected 
on day 5, and were about 40-fold lower than those of wildtype RSV; RSV 6120/ΔNS2/1030s also 
peaked on day 5, and replicated to about 4-fold higher titers than RSV ΔNS2/∆1313/I1314L, 
showing that indeed, RSV ΔNS2 with the 1030s mutation is slightly less restricted for replication 
than RSV ΔNS2/∆1313/I1314L. At 37°C, RSV ∆NS2/∆1313/I1314L was too restricted for a 
meaningful comparison, and RSV 6120/ΔNS2/1030s replicated to about 50-fold lower peak titers 
than wt RSV. This difference in peak titers of RSV 6120/ΔNS2/1030s and wt RSV was 
statistically significant and shows that RSV 6120/ΔNS2/1030s is restricted in this most predictive 
pre-clinical model. 
 
1.3.2.3 Evaluation of the Attenuation Phenotype of RSV ΔNS2/Δ1313/I1314L, RSV 6120/ΔNS2/1030s, 
and RSV 276 in Experimental Animals 
 
Recombinant RSV with deletion of ΔNS2 and codon 1313 of the polymerase ORF was evaluated 
for its ability to replicate in the upper and lower respiratory tract (URT and LRT, respectively) of 
mice. While wt RSV rA2 replicated to about 4.0 log10 PFU and 4.5 log10 PFU per gram of tissue 
in the upper and lower respiratory tracts of mice, replication of the deletion ΔNS2/Δ1313 mutant 
was reduced to below the level of detection, demonstrating attenuation. 
 
Replication and immunogenicity of RSV ΔNS2/Δ1313/I1314L were evaluated in nonhuman 
primates (African green monkeys, AGMs). AGMs are semi-permissive for RSV. AGMs which 
were seronegative for RSV were inoculated intranasally and intratracheally with RSV 
ΔNS2/Δ1313/I1314L; a dose of 1 x 106 PFU of vaccine in a 1 mL volume was administered per 
site to sedated juvenile male and female AGMs (total dose per animal: 2 x 106 PFU). 
Nasopharyngeal (NP) swabs were collected daily on Days 0 through 10 and Day 14, tracheal 
lavage (TL) samples were collected every other day from Day 2 through Day 10 and on Day 14, 
and virus shedding was analyzed by plaque assay. Serum RSV-neutralizing antibody titers were 
determined by a complement-enhanced 60% RSV plaque reduction neutralization assay. Results 
from studies following the same protocol, performed in animals from the same group and origin, 
inoculated with recombinant wt RSV A2 at the same dose, were included for comparison. Studies 
were approved by the Animal Care and Use Committee of NIAID, NIH. Virus shedding was 
analyzed by immunoplaque assay. Substantial shedding from the upper and lower respiratory 
tract over several days of the wt RSV A2 control virus was detected by plaque assay, with mean 
peak titers of 3.5 log10 PFU per mL in the URT and in the LRT. Compared to wt RSV A2, mean 
peak titers of RSV ΔNS2/Δ1313/I1314L were slightly reduced in the URT (3.2 log10 PFU per 
mL), and greatly reduced in the LRT (1.4 log10 PFU per mL), with detectable shedding in TL 
samples of only three of four animals. The sum of daily titers (area under the curve) of shedding 
of RSV ΔNS2/Δ1313/I1314L from the upper and lower respiratory tract was substantially lower 
than that of wt RSV A2. Despite the lower level of shedding, RSV ΔNS2/Δ1313/I1314L was 
immunogenic in AGMs. 
 
RSV 276 and RSV 6120/ΔNS2/1030s also were evaluated for their ability to replicate in AGMs 
in four independent non-GLP studies. The first two NHP studies were done to evaluate 
Experimental Lots of these viruses, and the subsequent two studies were done to test the clinical 
safety of the clinical trial materials (CTM) of RSV 276 and RSV 6120/ΔNS2/1030s. As described 
above, AGMs, seronegative for RSV, were inoculated intranasally and intratracheally with 1 x 
106 PFU of RSV 276 in a 1 mL volume per site (total dose per animal: 2 x 106 PFU). Results 
from studies following the same protocol, performed in animals from the same group and origin, 

 
IMPAACT 2021, FINAL Version 3.0 
Page 27 of 106 
28 April 2022 
inoculated with MEDI/ΔM2-2 and recombinant wt RSV A2 at the same dose, were included for 
comparison. Substantial shedding from the upper and lower respiratory tract over several days of 
the wt RSV A2 control virus was detected by plaque assay, with mean peak titers of 4.2 log10 
PFU per mL in the URT, and 4.1 log10 PFU per mL in the LRT. RSV 276 was infectious for 
AGMs, and except for a single RSV 276 inoculated animal with undetectable shedding from the 
URT, all animals shed the candidate vaccine viruses over several days from the upper and lower 
respiratory tract. However, compared to wt RSV A2, shedding of RSV 276 was reduced in the 
upper and lower respiratory tract. Mean peak titers of the experimental lot and of the CTM of 
RSV 276 were not significantly different from those of MEDI/ΔM2-2 in a previous study. Both 
lots of RSV 276 induced serum neutralizing antibody titers that were higher than those to 
MEDI/ΔM2-2, and comparable to those to the wt RSV A2 control virus. These results show that 
at a total dose of 2 x 106 PFU, administered intranasally and intratracheally, RSV 276 is 
attenuated to a similar degree as MEDI/ΔM2-2, and very immunogenic in AGMs.  
 
Compared to wt RSV A2, shedding of RSV 6120/ΔNS2/1030s was slightly reduced in the URT 
(mean peak titers of 3.8 log10 PFU), but higher than that of the previously tested RSV 
ΔNS2/Δ1313/I1314L virus (3.2 log10 PFU per mL). In the LRT, the mean peak titers were 4.6 
log10 PFU per mL for the Experimental Lot and 2.9 PFU per mL for the CTM of RSV 
6120/ΔNS2/1030s. Compared to the RSV ΔNS2/Δ1313/I1314L vaccine candidate (mean peak 
LRT titers: 1.4 log10 PFU per ml), RSV 6120/ΔNS2/1030s was less restricted in AGMs, and 
similarly immunogenic. 
 
These study results indicate that RSV ΔNS2/Δ1313/I1314L and RSV 276 are restricted for 
replication in AGMs, the most permissive RSV nonhuman primate model that is currently 
available. At the dose of 1 x 106 PFU per site, shedding of these vaccine candidates was 
detectable from the URT and LRT, but was substantially reduced compared to recombinant wt 
RSV A2. Despite the low level of shedding, all of these candidates were very immunogenic in 
AGMs. Overall, replication and immunogenicity of RSV 276 were comparable to MEDI/ΔM2-2. 
RSV 6120/ΔNS2/1030s was less restricted than RSV ΔNS2/Δ1313/I1314L in AGMs. In 
summary, it is anticipated that these investigational RSV ΔNS2/Δ1313/I1314L, RSV 
6120/ΔNS2/1030s, and RSV 276 live vaccine candidates will be attenuated, immunogenic, and 
safe upon intranasal application in RSV-seronegative children.  
 
1.3.3 
Previous Clinical Experience 
 
RSV ΔNS2/Δ1313/I1314L, RSV 6120/ΔNS2/1030s, and RSV 276 have recently been evaluated 
in first-in-human Phase I studies. The RSV 276 vaccine is similar to the live-attenuated 
recombinant RSV MEDI ∆M2-2 vaccine virus, which has been studied in RSV-seropositive 
cohorts, and in RSV-seronegative children. 
 
1.3.3.1 RSV ΔNS2/Δ1313/I1314L 
 
Prior to RSV ΔNS2/Δ1313/I1314L and RSV 6120/ΔNS2/1030s, three RSV vaccine viruses with 
NS2 deletion (rA2cpΔNS2, rA2cp248/404ΔNS2, and rA2cp530/1009ΔNS2) had been evaluated 
in clinical studies (27), confirming that the deletion of the NS2 gene attenuates RSV. rA2cpΔNS2 
was over-attenuated for adults but under-attenuated for use in young children, whereas both 
rA2cp248/404ΔNS2 and rA2cp530/1009ΔNS2 were over-attenuated and insufficiently 
immunogenic for seronegative children (27). 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 28 of 106 
28 April 2022 
Based on these results, RSV∆NS2/∆1313/I1314L and RSV 6120/ΔNS2/1030s were developed. In 
a recent Phase I trial (NCT01893554), RSV∆NS2/∆1313/I1314L was evaluated in RSV-
seropositive children 12-59 months of age at a dose of 106 PFU (10V, 5P), and no shedding or 
immune response was detected, indicative of attenuation. Next, it was evaluated in seronegative 
children 6-24 months of age at two sequential dose levels. At the lower dose of 105 PFU (15V, 
7P), the vaccine was poorly infectious (7% and 73% of recipients shed virus detected by culture 
and RT-qPCR, respectively) and immunogenicity was low. At the higher dose of 106 PFU (20V, 
10P), 80% and 90% of recipients shed virus detected by culture and RT-qPCR, respectively 
[geometric mean peak titers (GMT) 1.8 log10 PFU/mL; 3.5 log10 copies/mL]. Moreover, 85% and 
80% had ≥4-fold increases in RSV F IgG and RSV-neutralizing serum antibody titers, 
respectively. The serum antibody response was durable over the RSV surveillance season, and the 
vaccine primed for a strong anamnestic response to wild-type RSV. In the 106 dose cohort, during 
the first 28 days after receipt of study product, 11 of the 20 (55%) vaccine recipients had a total of 
15 episodes of mild respiratory or febrile illnesses (Grade 1, except for a single Grade 2 fever). 
Vaccine virus was detected by culture during one of these 15 episodes (together with 
parainfluenza virus type 3), and by PCR during six of these episodes. Rhinovirus was detected 
during five of the 15 episodes in vaccine recipients. Of the 10 placebo recipients, eight (80%) had 
a total of 11 episodes of respiratory or febrile illnesses during the first 28 days. The respiratory 
illnesses included four Grade 1 illnesses (rhinorrhea and/or cough), and two Grade 2 illnesses 
(croup and stridor; both protocol-specified adverse events). An episode of otitis media (Grade 2) 
was also observed in this group. Additionally, there were three episodes of Grade 3 fever, and one 
episode of Grade 2 fever among placebo recipients. Enterovirus, rhinovirus, adenovirus, and 
bocavirus were detected in five of these 11 illness episodes. Based on these data, there was no 
evidence of excess respiratory illness associated with receipt of a 106 dose of RSV 
∆NS2/∆1313/I1314L. ∆NS2/∆1313/I1314L is presently being evaluated in 4- to 6-month-old 
infants (unscreened for RSV antibodies). In this younger cohort, seven participants have 
completed the post-vaccination acute and post-acute-phase follow-up, without any safety signals. 
 
1.3.3.2 RSV MEDI/ΔM2-2 and RSV 276 
 
Several versions of RSV vaccine candidates with M2-2 deletion have recently been evaluated 
[Table 1; (6, 28-31)]. The first vaccine candidate, designated RSV MEDI/ΔM2-2, was 
sequentially evaluated in adults, RSV-seropositive children, and RSV-seronegative infants and 
children (6). Fifteen healthy adults received a 106 PFU dose of this vaccine in an open-label study. 
The vaccine was generally well tolerated, and vaccine virus was not detected in nasal washes 
collected from any of the vaccine recipients. Serum antibody responses were not detected in any 
of these adult vaccinees. Thus, there was no evidence of replication of RSV MEDI/ΔM2-2 in 
adult vaccinees. A 106 PFU dose of RSV MEDI/ΔM2-2 was subsequently evaluated in 
RSV-seropositive children ages 12-59 months (double-blind, placebo-controlled). Ten children in 
this RSV-seropositive cohort received a 106 PFU dose of vaccine, and five received placebo. 
Among the vaccinees, five children had rhinorrhea or nasal congestion, which was associated in 
all cases with shedding of rhinovirus and with shedding of adenovirus (1 child) or enterovirus (1 
child). All illnesses were mild in severity. None of the vaccinees shed vaccine virus, indicating 
that there was also no evidence of replication of RSV MEDI/ΔM2-2, evaluated at a dose of 106 
PFU in RSV-seropositive children. 
 
RSV MEDI/∆M2-2 was subsequently evaluated at a 105 PFU dose in RSV-seronegative children. 
RSV MEDI/∆M2-2 replicated at low titers yet induced substantial RSV-neutralizing antibody 
responses in RSV-seronegative children. Vaccine virus was detected by culture in only 60% (12 
of 20) RSV-seronegative vaccinees, at a low mean peak titer of 1.5 log10 PFU/ml. However, 17 of 
20 had vaccine virus detected by qRT-PCR. Four-fold or greater increases in RSV-neutralizing 

 
IMPAACT 2021, FINAL Version 3.0 
Page 29 of 106 
28 April 2022 
antibodies occurred in 19 of 20 children, with mean log2 titers of 2.7 ± 0.9 before study product 
administration and 6.6 ± 1.1 following study product administration. Thus, while the levels of 
infectivity and replication of RSV MEDI/∆M2-2 were similar to what might be seen with an 
over-attenuated vaccine virus, the levels of RSV-specific serum antibodies indicated that this 
virus was surprisingly immunogenic. Respiratory illnesses were observed in 85% of vaccinees 
and 70% of placebo recipients, including fever (20% vs. 30%), rhinorrhea (85% vs. 50%), cough 
(35% vs. 30%), and otitis media (5% vs. 0%). Lower respiratory tract illness (LRI) was not 
detected in any participant. Transmission of vaccine virus occurred in a set of 13-month-old twin 
study participants; both were minimally symptomatic and vaccine virus shed retained the M2-2 
deletion and remained very highly restricted in the secondary infection. When data on vaccine 
virus infectivity and immunogenicity in RSV-seronegative children were compared to those 
achieved with rA2 cp248/404/1030/ΔSH, a live-attenuated RSV vaccine candidate that was well 
tolerated and immunogenic in previous pediatric Phase I studies (15), it was found that the 
MEDI/∆M2-2 shedding was significantly more restricted. However, the post-study product 
administration RSV-neutralizing serum antibody achieved (GMT = 1:97) was significantly 
greater with RSV MEDI/∆M2-2 than with rA2 cp248/404/1030/ΔSH. Surveillance during the 
subsequent RSV season showed that several RSV-seronegative RSV MEDI/∆M2-2 recipients had 
substantial antibody rises without reported medically attended illness, suggesting that the vaccine 
primed for strong anamnestic responses to RSV. The M2-2 deletion was stable in all shed vaccine 
virus samples that were tested (6).  
 
Thus, the MEDI/∆M2-2 phenotype appears to be very promising for an RSV vaccine; 
MEDI/∆M2-2 remained the lead candidate after evaluation of several other ∆M2-2 candidates 
with differences affecting replication and temperature sensitivity [Table 1; (6, 28-31)]. 
MEDI/∆M2-2 was not available for further clinical analysis, and RSV 276 was designed to be 
similar to MEDI/∆M2-2. RSV 276 differs from MEDI/ΔM2-2 by four nucleotides in noncoding 
sequence. It is reasonable to expect that these two viruses will have similar levels of replication 
and attenuation in pre-clinical testing and in clinical testing humans, and likely will be 
phenotypically indistinguishable. In pre-clinical nonhuman primate studies in AGMs, the most 
permissive RSV animal model currently available, the level of replication of RSV 276 was 
similar to MEDI/ΔM2-2.  
 
RSV 276 was evaluated under the protocol IMPAACT 2018/CIR 321 (NCT03422237, 
NCT03227029). Under this protocol, children 6 to 25 months of age received the RSV 
ΔNS2/Δ1313/I1314L or RSV 276 vaccines or placebo (randomization 2:2:1). The study enrolled 
52 children in the two vaccine arms (26 each) and 13 children in the placebo arm. Three children 
had no data after entry and are not included in the analysis. During the 28 days post-inoculation, 
mild upper respiratory and/or febrile events occurred often in both vaccine and placebo recipients, 
with 64% [90% CI: (46%, 80%)] of RSV ΔNS2/Δ1313/I1314L recipients, 84% [90% CI: (67%, 
94%)] of RSV 276 recipients, and 58% [90% CI: (32%, 82%)] of placebo recipients having one 
or more illness episodes. Most of the respiratory symptoms were Grade 1. The only Grade 3 
events were fever, which occurred in two RSV ΔNS2/Δ1313/I1314L vaccinees and one RSV 276 
vaccine recipient. Grade 2 fever occurred in one RSV ΔNS2/Δ1313/I1314L vaccinee, two RSV 
276 vaccinees, and one placebo recipient. Grade 2 otitis media occurred in one RSV 
ΔNS2/Δ1313/I1314L vaccinee and two RSV 276 vaccine recipients. Grade 2 cough occurred in 
one RSV 276 vaccine recipient and one placebo recipient. There were two Grade 2 URIs 
reported, both in RSV ΔNS2/Δ1313/I1314L vaccinees. All other events were Grade 1. There 
were no LRIs or SAEs. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 30 of 106 
28 April 2022 
1.4 
Rationale 
 
In previous Phase IA studies in RSV-seronegative infants and children 6 to 24 months of age, 
RSV vaccines based on two different attenuation strategies have been evaluated. The first 
approach is based on deletion of the gene encoding the RSV interferon/apoptosis antagonist NS2 
protein (∆NS2). Deletion of NS2 attenuates the virus and may enhance immunogenicity. The best 
∆NS2 candidates, RSV ∆NS2/∆1313/I1314L and RSV 6120/ΔNS2/1030s, additionally contain a 
genetically stabilized attenuating and temperature sensitivity mutation in the L protein (codon 
deletion ∆1313, as well as a missense mutation I1314L that prevents a de-attenuating mutation 
that otherwise can occur at position 1314 in RSV ∆NS2/∆1313/I1314L; genetically stabilized 
mutation 1030s in RSV 6120/ΔNS2/1030s). The second approach is based on deletion of the 
RSV M2-2 open reading frame (∆M2-2), which results in up-regulation of viral antigen synthesis, 
increasing immunogenicity per infectious unit. The initial ∆M2-2 vaccine candidate, MEDI/∆M2-
2, is not available for further study. A similar virus, called RSV 276, has now been prepared. 
Based on infectivity, safety, and immunogenicity data, these three candidate vaccines were 
identified as the strongest candidates to move into expanded Phase I/II trials. The overall goal of 
IMPAACT 2021 is to assess the safety and immunogenicity of the three vaccine candidates in a 
larger study and choose one or two to move forward into future large-scale studies.   
 
In IMPAACT 2021, RSV ∆NS2/∆1313/I1314L, RSV 6120/ΔNS2/1030s, and RSV 276 will be 
evaluated side-by-side. A placebo group equal in size to each vaccine group is needed to detect 
safety signals, including excess solicited adverse events (respiratory or febrile illness) that might 
be associated with one or more of the study products, above the high background of 
respiratory/febrile illness in this age group. Enrollment will take place outside the time during 
which wt RSV circulates in the community at each study site. RSV circulation will be determined 
by the Protocol Team through local and national surveillance and communication with the study 
sites, with additional guidance provided in the Manual of Procedures (MOP). Surveillance of 
study participants will take place during the RSV season that starts in the calendar year of study 
product administration. The goal was to complete enrollment within a single enrollment season, 
followed by planning of subsequent, larger safety and efficacy studies. However, the study was 
not fully accrued in the first season. The DSMB reviewed results during the winter RSV season 
following the first enrollment season (2019) and recommended that the study should continue as 
planned when feasible in the context of circulating severe acute respiratory syndrome coronavirus 
2 (SARS-CoV-2) and the associated coronavirus disease (COVID-19) pandemic. Due to COVID-
19, the study was not able to reopen during the second enrollment season (2020), and no sites 
were able to resume enrollment during the third enrollment season (2021); thus, enrollment is 
anticipated to resume for a fourth enrollment season (e.g., 2022). If a fifth enrollment season 
(e.g., 2023) is considered, the DSMB will review results from the fourth enrollment season (e.g., 
2022) to confirm if all candidate vaccines should remain in the study.  
 
The study population, the inclusion and exclusion criteria, most primary objectives, and other 
aspects of the proposed study adhere closely to previous IMPAACT RSV studies 2000, 2011, 
2012, 2013, and 2018. The schedule of evaluations is simplified compared to that of the previous 
studies; the number of in-person visits and scheduled clinical assessments are greatly reduced 
from seven to a single one over the first 28 days after study product administration, which should 
facilitate enrollment and minimize the labor required for the study. As with previous studies, 
participants with illness may have additional visits to assess the severity of the illness (see 
Section 6.8 for Illness Visits). Nasal swabs will be collected at Illness Visits (note that nasal 
washes were collected under protocol Version 1.0; see Section 3 for additional detail). 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 31 of 106 
28 April 2022 
Rationale for evaluation of immunogenicity on Day 28 and Day 56  
To date, all candidate vaccine studies with live attenuated RSV vaccines have used Day 56 as the 
time point to assess serum antibody response. This time point was used for two reasons: 1) it was 
believed that since this is a primary response (rather than an anamnestic [memory] response), it 
may not have reached maximal levels by Day 28 and 2) maximal replication of these highly 
attenuated vaccine viruses does not typically occur until Day 7, which may also delay induction 
of the immune response. However, some children may have become infected with wildtype RSV 
by the time their Day 56 specimens are collected, resulting in a >4-fold antibody response even if 
there was no response to vaccine. If this window could be shortened to 28 days, a time when 
antibody responses are generally present after vaccine, the frequency of antibody responses due to 
community-acquired wild-type RSV could be greatly reduced. This will be very important for 
future, large-scale studies. However, the change to Day 28 measures cannot be made without first 
confirming that responses are detectable on Day 28 and are comparable to those measured on Day 
56. It is anticipated that all future studies will measure response at a single timepoint (hopefully 
Day 28).   
 
Evaluation of study products 
There are four time points at which data have been/will be reviewed to allow a determination of 
which study arms will remain open. The first was prior to the time the study is open when interim 
results of IMPAACT 2018/CIR 321 and CIR 322 became available. These studies provided 
additional safety and immunogenicity data for each of the three candidate vaccines included in 
IMPAACT 2021. Each of the three products was evaluated by a subgroup of the Protocol Team 
using the go/no-go criteria in Table 3 below; all three products passed the go criteria. If the 
subgroup of Protocol Team members had determined that any product did not pass the go criteria, 
they would have shared this information with the DSMB members to make a final decision about 
whether that candidate arm may be dropped from IMPAACT 2021 prior to the opening of the 
study. Note that each candidate vaccine has been studied in a similar number of participants so 
far, so similar criteria were applied across the three vaccine candidates. The 70% cutoff specified 
below is considered to be a reasonable threshold to ensure that development of a potentially 
viable candidate vaccine is not stopped prematurely. 
 
Table 3: Criteria for Including a Vaccine in IMPAACT 2021 
 
Yes 
No 
1. Is the upper limit of the 95% confidence interval for the 
percentage of participants exhibiting a vaccine take (defined as 
the detection of vaccine virus shedding by culture or RT-PCR, 
and/or ≥4-fold rise in RSV-specific serum antibodies at the Day 
56 Visit) less than 70%? 
  
  
2. Have more than two participants receiving the specific product 
experienced LRI of ≥ Grade 2 in the 28 days following study 
product administration for which vaccine virus was isolated by 
culture at the time of illness without other potential explanation? 
  
  
3. Were there two or more participants who experienced vaccine-
associated Grade 4 events of similar type (as listed below) after 
study product administration with presence of vaccine virus 
without other potential explanation? 
                Otitis media within 28 days of study product administration 
                Pharyngitis within 28 days of study product administration 
  
  
 
For any specific candidate vaccine, a response of “yes” to any of these questions could have 

 
IMPAACT 2021, FINAL Version 3.0 
Page 32 of 106 
28 April 2022 
resulted in that candidate vaccine being removed from IMPAACT 2021 prior to the study 
opening.   
 
The second time point at which data were reviewed was during the winter RSV season following 
the first enrollment season (2019), given that the study was not yet fully accrued. Using the 
criteria in Table 4 as guidance, the DSMB recommended that the study should continue as 
planned when feasible in the context of the COVID-19 pandemic. Due to COVID-19, the study 
could not open in the second enrollment season (2020). During the winter of 2021, newly 
available unblinded data from IMPAACT 2018/CIR 321 and CIR 322 were reviewed, and it was 
determined that the RSV 276 vaccine arm of IMPAACT 2021 would be closed to further 
enrollment under protocol V2.0 (this was the third time point at which data were reviewed); this 
arm remains closed under protocol V3.0. No sites were able to resume enrollment during the third 
enrollment season (2021); thus, enrollment is anticipated to resume for a fourth enrollment season 
(e.g., 2022). If a fifth enrollment season (e.g., 2023) is considered, the DSMB will review results 
from the fourth enrollment season (e.g., 2022) to confirm if all candidate vaccines should remain 
in the study (this is the fourth time point at which data will be reviewed). The DSMB will use the 
criteria in Table 4 as guidance in making that decision.  
 
Table 4: Post-Accrual Season Study Review Criteria 
Yes 
No 
1. Is there a statistically significant (p<0.05) difference in the 
percentage with immune response (≥4-fold rise in serum RSV-
neutralizing antibodies) to the candidate vaccines such that one or 
two products can be identified to be immunologically superior to 
the remaining product or products, with the absence of a safety 
signal among the higher performing product(s)? 
  
  
If yes, the DSMB may recommend that the study close to accrual 
If no, the DSMB will consider the following questions for each specific product: 
2. Is the upper limit of the 95% confidence interval for the 
percentage of participants exhibiting a ≥4-fold rise in serum 
RSV-neutralizing antibodies at the Day 56 Visit less than 70%? 
  
  
3. Have more than two participants receiving the specific product 
experienced LRI of ≥ Grade 2 in the 28 days following study 
product administration for which vaccine virus was isolated 
without other potential explanation? 
  
  
4. Were there two or more participants who experienced vaccine-
associated Grade 4 events of similar type (as listed below) after 
study product administration with presence of vaccine virus 
without other potential explanation? 
                Otitis media within 28 days of study product administration 
                Pharyngitis within 28 days of study product administration 
  
  
 
For any specific candidate vaccine, a response of “yes” to any of these questions could result in 
that candidate vaccine arm being closed. As noted above, the RSV 276 vaccine arm was closed to 
further enrollment under protocol V2.0 and remains closed under protocol V3.0. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 33 of 106 
28 April 2022 
1.5 
Hypotheses 
 
The live-attenuated RSV vaccine candidates RSV ΔNS2/Δ1313/I1314L, RSV 6120/ΔNS2/1030s, 
and RSV 276 will each be safe and immunogenic in RSV-seronegative recipients. However, these 
vaccine candidates may have safety signals that become apparent only when analyzed in a larger 
number of participants, and the candidates may differ in the magnitude and longevity of antibody 
responses, and in responses observed following naturally occurring RSV infection. To move 
forward, the vaccines should: 
 
• 
be safe, and  
• 
result in at least 70% of the population of vaccine recipients having a ≥4-fold rise in serum 
RSV-neutralizing antibody titers from pre-study product administration to the Day 56 
Visit after study product administration  
 
2 
OBJECTIVES  
 
2.1 
Primary Objectives 
 
The primary objectives of this study are the following:  
 
2.1.1 
Safety: To estimate and compare (each vaccine group to placebo) the frequency and 
severity of adverse events (AEs) following study product administration (Day 0) through 
Day 56 
 
2.1.2 
Immunogenicity: To estimate and compare (between the vaccine groups and to the 
benchmark of 70%) the percentage of vaccinees having a ≥4-fold rise in serum RSV-
neutralizing antibodies at the Day 56 Visit 
 
2.2 
Secondary Objectives 
 
The secondary objectives of this study are to:  
 
2.2.1 
Immunogenicity: To estimate and compare (between the vaccine groups) the percentage 
of vaccinees with a ≥4-fold rise in serum IgG antibody to RSV F protein (RSV F IgG) at 
the Day 56 Visit 
 
2.2.2 
Immunogenicity: To estimate and compare (between the vaccine groups) the titers of 
serum RSV F IgG and serum RSV-neutralizing antibodies at the Day 56 Visit 
 
2.2.3 
Safety: To describe and compare the frequency and severity of RSV-associated, 
medically attended, acute respiratory illness (RSV-MAARI) and RSV-associated, 
medically attended, acute lower respiratory illness (RSV-MAALRI) in the placebo and 
vaccine arms during RSV season  
 
2.3 
Exploratory Objectives 
 
2.3.1 
To evaluate the association of vaccine virus shedding with adverse events: To assess the 
incidence and magnitude of vaccine virus shedding in samples collected at Illness Visits 
associated with solicited AEs on Study Days 0 through 28 and with serious AEs from 
Study Day 0 through Day 56  

 
IMPAACT 2021, FINAL Version 3.0 
Page 34 of 106 
28 April 2022 
 
2.3.2 
Immunogenicity – timing of maximum response: To estimate and compare serum RSV F 
IgG and serum RSV-neutralizing antibody responses at the Day 28 and 56 Visits in each 
vaccine group 
 
2.3.3 
Immunogenicity – magnitude of anamnestic response: To estimate and compare (each 
vaccine group to placebo and between the vaccine groups) the titers of serum RSV F IgG 
and serum RSV-neutralizing antibodies in participants infected with wt RSV during the 
RSV season  
 
2.3.4 
Immunogenicity – durability of vaccine-induced RSV antibodies: to estimate and 
compare (between the vaccine groups), the magnitude of RSV serum antibody titers in 
samples collected at the Day 56 and Post-RSV Season Visits among vaccine recipients 
who do not have evidence of RSV infection during RSV season 
 
 
3 
STUDY DESIGN 
 
The study will be conducted in children at selected sites in the United States. The vaccines will be 
evaluated in RSV-seronegative children ≥6 months (180 days) at the time of screening to <25 
months (750 days) of age at the time of enrollment. For the purpose of this study, RSV-
seronegative is defined as having a serum neutralizing antibody titer of <1:40. This definition has 
been used in previous evaluations of live-attenuated RSV vaccines (15, 26, 32). In these previous 
studies, live-attenuated RSV vaccines were highly restricted in replication and poorly 
immunogenic in children with titers ≥1:40 but were far less restricted in replication and highly 
immunogenic in children with titers <1:40. These data suggest that in this age group, this 
neutralizing antibody cutoff can distinguish effectively between children who have previously 
been infected with RSV and those who have not. 
 
The study will be double-blind, randomized, and placebo-controlled. As with protocol V2.0, 
under protocol V3.0, RSV-seronegative participants will be randomized equally (1:1:1) to one of 
the two active vaccine arms or the placebo arm. The total expected sample size is approximately 
130, including 40 each in the placebo and two candidate vaccine arms open under protocol V2.0 
and V3.0, as well as all participants previously randomized to receive RSV 276 vaccine under 
protocol V1.0 prior to closure of this arm. Adjustments to the candidate vaccines included in the 
study may be made as outlined in Section 1.4 (e.g., the RSV 276 arm was closed to further 
enrollment under protocol V2.0 and remains closed under protocol V3.0). Placebo recipients are 
needed in pediatric studies to distinguish the background respiratory and febrile illnesses that 
occur in children from those attributable to study vaccine. These numbers were chosen based 
upon experience with Phase I evaluation of other live-attenuated respiratory virus candidate 
vaccines (25-27), statistical considerations (see Section 9), and feasibility for reaching the 
enrollment goal within one season.   
 
Enrollment will occur outside the time during which wt RSV circulates in the community at each 
study site. RSV circulation will be determined by the Protocol Team through local and national 
surveillance and communication with the study sites, with additional guidance provided in the 
Manual of Procedures (MOP). The goal was to complete enrollment within a single enrollment 
season. Accrual was not completed in the first enrollment season (2019), and the DSMB 
recommended that the study continue as planned when feasible in the context of the COVID-19 
pandemic. Due to the COVID-19 pandemic, enrollment was paused during the second enrollment 

 
IMPAACT 2021, FINAL Version 3.0 
Page 35 of 106 
28 April 2022 
season (2020), and no sites were able to resume enrollment during the third enrollment season 
(2021). Enrollment will therefore be extended into a fourth enrollment season (e.g., 2022) and 
may be extended into a fifth enrollment season (e.g., 2023). This will increase the accrual time. 
Specific study phases are described in the paragraphs that follow. 
 
Throughout study follow-up, reported AEs will be clinically assessed via in-person or telehealth 
(telephone or video) Illness Visits as described in Section 6.8. Illness Visits may be conducted by 
study staff or, alternatively, by other medical providers if medical records from the visit can be 
made available to study staff and a parent/guardian can collect the nasal swab described below.  
 
A nasal swab to evaluate for RSV and other respiratory pathogens (adventitious agents) will be 
collected for each Illness Visit (see Section 6.8, Appendix I, and Appendix II). If a 
parent/guardian is comfortable collecting a nasal swab sample, the sample may be collected by 
the parent/guardian during or immediately after a telehealth visit. If parent/guardian is not 
comfortable collecting the sample, the nasal swab should be collected by study staff. 
 
Note: Under protocol Version 1.0, nasal wash samples were collected from participants. As with 
protocol Version 2.0, under protocol V3.0, the collection has been changed to nasal swab 
samples, to decrease potential exposure of study staff to SARS-CoV-2 and allow 
parents/guardians to collect samples, if possible and feasible for parents/guardians 
 
Duration of participation in the initial part of the study is 56 days, which consists of an Acute and 
a Post-Acute Phase. The schedule of events during the Acute Phase and Post-Acute Phase is 
shown in Appendix I. During the Acute Phase (which lasts from the day of study product 
administration (Study Day 0) to midnight on the 28th day following Day 0), participants will be 
contacted daily. These contacts will be conducted by phone, text, or email to assess interim 
medical history. Participants with episodes of fever Grade 2 or higher, URI (excluding rhinorrhea 
without cough), or otitis media will require an in-person Illness Visit; the timing of the visit 
depends on the grade of the event per Section 6.8. Cases of fever <Grade 2 and rhinorrhea 
without cough may be clinically assessed via telehealth (telephone or video) Illness Visit. 
Participants who have a possible LRI will have an in-person Illness Visit within one day of the 
reported onset of the LRI, and an in-person or telehealth (telephone or video) follow-up 
assessment is required one to three days after the initial assessment. See Section 6.8 for more 
information. 
 
During the Post-Acute Phase (Study Day 29 to midnight on the 56th day following Day 0), study 
participants will have a scheduled visit on Day 56. Episodes of Serious Adverse Events from Day 
29 through 56 will have an in-person or telehealth (telephone or video) Illness Visit (see Section 
6.8, Appendix I).  
 
In addition to the Acute and Post-Acute Phases, the study has a third timeframe during which the 
incidence and severity of illness suggestive of RSV occurring during the RSV season that starts in 
the calendar year of the participant’s study product administration are assessed. During the RSV 
Season Surveillance Period, encompassing November 1st to March 31st for most sites or—for sites 
with local RSV seasons that differ—as specified on a site-by-site basis in the MOP, site study 
staff will make weekly contact with the participants to identify medically attended episodes of 
fever, URI or LRI, or otitis media. Medically attended events during the RSV Season 
Surveillance Period are defined in Section 6.6. Such an episode may require an Illness Visit (see 
Section 6.8, Appendix II).  
 
All participants will have a Post-RSV Season Visit (April 1st to April 30th) in the calendar year 

 
IMPAACT 2021, FINAL Version 3.0 
Page 36 of 106 
28 April 2022 
following study product administration to collect blood for measurement of RSV immune 
response to further assess the durability of the vaccine response and to assess the immune 
response to naturally occurring wt RSV infection. Thus, the maximum duration of participation 
will be up to 15 months, depending upon the time of enrollment relative to the RSV season. 
 
Figure 2 summarizes the initial study phases and additional study timeframes. There may be 
overlap in these various timeframes.  
 
Figure 2: Initial Study Phases and Additional Study Timeframes 
  
 
 
4 
STUDY POPULATION 
 
The vaccines will be evaluated in RSV-seronegative children ≥6 months (180 days) at the time of 
screening to <25 months (750 days) of age at the time of enrollment. As with protocol V2.0, 
under protocol V3.0, participants will be randomized equally (1:1:1) to receive one of the two 
candidate vaccines or placebo (40 per arm) from US sites only. Children will be selected for 
participation according to the criteria in Sections 4.1 and 4.2. The sections that follow describe 
study-specific co-enrollment considerations; the recruitment, screening, and enrollment process; 
and participant retention and withdrawal or termination. Sites are expected to obtain the potential 
participant’s medical records from the potential participant’s primary care provider to review for 
eligibility. The criteria related to the health status (including CD4 counts) and age of household 
members, day care attendance, and scheduled vaccine administration in relation to study product 
administration (except as noted in the medical record) may rely on parent/guardian report.  
 
Any questions regarding interpretation of the inclusion/exclusion criteria or other considerations 
described in this section should be forwarded to the Protocol Team. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 37 of 106 
28 April 2022 
4.1 
Inclusion Criteria 
 
Potential participants must meet all of the following criteria in order to be included in this study: 
 
 
4.1.1 
≥6 months (defined as ≥180 days) of age at the time of screening and <25 months 
(defined as < 750 days) of age at the time of enrollment. 
 
4.1.2 
In good health based on review of the medical record, history, and physical examination, 
without evidence of chronic disease.  
 
4.1.3 
Parent/guardian is willing and able to provide written informed consent as described in 
protocol Section 12.3.  
 
Note: All sites must follow the policies and procedures of all applicable IRBs; this 
includes single IRB (sIRB) policies and procedures. Refer to Section 12.1 for more 
information on sIRB oversight of US sites. 
 
4.1.4 
Seronegative for RSV antibody, defined as a serum RSV-neutralizing antibody titer 
<1:40 at screening from a sample collected no more than 42 days prior to study product 
administration. 
 
Note: results from specimens collected during screening for any study of an RSV vaccine 
developed by the LID (NIAID, NIH) are acceptable. If study product will not be 
administered the same day as randomization (see Section 6.2), it must be administered no 
more than 42 days after the screening sample is collected.  
 
4.1.5 
Growing normally for age in the opinion of the site clinician in the six months prior to 
enrollment AND has a current height and weight above the 3rd percentile for age and sex 
per CDC (WHO) growth standards. 
 
4.1.6 
Has received routine immunizations appropriate for age (as per national Center for 
Disease Control Advisory Committee on Immunization Practices [ACIP]). Note: 
COVID-19 vaccination will not be required unless fully licensed for this age group and 
ACIP-recommended. See MOP for further guidance. 
 
4.1.7 
Is expected to be available for the duration of the study. 
 
4.1.8 
If born to an HIV-infected woman, potential participant must have documentation of 2 
negative HIV nucleic acid (RNA or DNA) test results from samples collected on different 
dates with both collected when ≥4 weeks of age and at least one collected when ≥16 
weeks of age, and no positive HIV nucleic acid (RNA or DNA) test; or 2 negative HIV 
antibody tests, both from samples collected at ≥24 weeks of age. If potential participant 
was breastfed by an HIV-infected woman, each of the sampling times noted above must 
be measured in weeks after the last exposure to breast milk, rather than weeks of age.   
 
4.2 
Exclusion Criteria 
 
Potential participants who meet any of the following criteria will be excluded from this study: 
 
4.2.1 
Prior laboratory-confirmed RSV infection. 

 
IMPAACT 2021, FINAL Version 3.0 
Page 38 of 106 
28 April 2022 
 
4.2.2 
Known or suspected HIV infection or impairment of immunological functions. 
 
4.2.3 
Receipt of immunosuppressive therapy, including any systemic, nasal, or inhaled 
corticosteroids within 28 days of enrollment. Note: Cutaneous (topical) steroid treatment 
is not an exclusion. 
 
4.2.4 
Any receipt of bone marrow/solid organ transplant. 
 
4.2.5 
Major congenital malformations (such as congenital cleft palate) or cytogenetic 
abnormalities. 
 
4.2.6 
Previous enrollment in this trial, previous maternal or pediatric receipt of a licensed or 
investigational RSV vaccine, or previous maternal or pediatric receipt of or planned 
administration of any anti-RSV product (such as ribavirin or RSV IG or RSV mAb). 
 
4.2.7 
Any previous anaphylactic reaction.  
 
4.2.8 
Any known hypersensitivity to any study product component. 
 
4.2.9 
Heart disease. Note: Potential participants with cardiac abnormalities documented to be 
clinically insignificant and requiring no treatment may be enrolled. 
 
4.2.10 Lung disease, including any history of reactive airway disease or medically diagnosed 
wheezing.   
 
4.2.11 Member of a household that contains a person with chronic lung disease, including but 
not limited to chronic obstructive pulmonary disease (COPD), emphysema, or home 
oxygen use, reactive airway disease or asthma.  
 
Note: Asthma or reactive airway disease in a household member is not exclusionary 
unless the household member has taken oral steroids for asthma management in the past 
month and/or has been hospitalized for asthma in the past month. 
 
4.2.12 Member of a household that contains, or will contain, an infant who is less than 4 months 
of age at the enrollment date through Day 14. 
 
4.2.13 Member of a household that contains another child/other children who is/are enrolled or 
is/are scheduled to be enrolled in IMPAACT 2021 on a different date and has/have not 
completed the Day 56 Visit (i.e., all eligible children from the same household must be 
enrolled/receive study product on the same date, or additional children in the household 
may be screened, enrolled, and randomized independently after other children in the 
household complete the Day 56 Visit).  
 
4.2.14 Member of a household that contains another child who is, or is scheduled to be, enrolled 
in another study evaluating an intranasal live-attenuated RSV vaccine, AND there has 
been or will be an overlap in residency during Day 0 to 14 of that other child’s 
participation in the study. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 39 of 106 
28 April 2022 
4.2.15 Member of a household that contains an immunocompromised individual, including, but 
not limited to: 
• 
a person who has been diagnosed with cancer and who has received chemotherapy 
within the 12 months prior to enrollment; or 
• 
a person living with a solid organ, cord blood, or bone marrow transplant. 
 
4.2.16 Shares a daycare room with infants less than 4 months of age, and parent/guardian is 
unable or unwilling to suspend daycare for 14 days following study product 
administration.  
 
4.2.17 Any of the following events at the time of enrollment: 
• 
fever (rectal temperature of ≥100.4°F (38°C)), or  
• 
upper respiratory signs or symptoms (including but not limited to rhinorrhea, 
cough, or pharyngitis) or 
• 
nasal congestion significant enough to interfere with successful study product 
administration, or  
• 
otitis media. 
 
Note: if participant is randomized and subsequently noted to have any of the above, study 
product administration must be deferred per protocol Section 6.2.  
 
4.2.18 Receipt of the following prior to enrollment (start counting backwards with ‘1’ as the day 
of planned study product administration): 
• 
any inactivated vaccine or live-attenuated rotavirus vaccine within the 14 days 
prior, or  
• 
any live vaccine, other than rotavirus vaccine, within the 28 days prior, or 
• 
another investigational vaccine or investigational drug within 28 days prior Note: if 
COVID-19 vaccine has EUA approval and ACIP recommendation for this age 
group, it is not considered investigational. 
 
4.2.19 Scheduled administration of the following after planned study product administration 
(start counting with ‘1’ as the day of planned study product administration): 
• 
inactivated vaccine or live-attenuated rotavirus vaccine within the 14 days after, or 
• 
any live vaccine other than rotavirus in the 28 days after, or 
• 
another investigational vaccine or investigational drug in the 56 days after Note: if 
COVID-19 vaccine has EUA approval and ACIP recommendation for this age 
group, it is not considered investigational. 
 
4.2.20 Receipt of immunoglobulin, any antibody products, or any blood products within the past 
6 months prior to enrollment 
 
4.2.21 Receipt of any of the following medications within 3 days prior to study enrollment: 
• 
systemic antibacterial, antiviral, antifungal, anti-parasitic, or antituberculous 
agents, whether for treatment or prophylaxis, or 
• 
intranasal medications, or 
• 
other prescription medication except as listed below 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 40 of 106 
28 April 2022 
Permitted concomitant medications (prescription or non-prescription) include nutritional 
supplements, medications for gastroesophageal reflux, eye drops, and topical 
medications, including (but not limited to) cutaneous (topical) steroids, topical 
antibiotics, and topical antifungal agents. 
 
4.2.22 Born at less than 34 weeks gestation. 
 
4.2.23 Born between 34 weeks gestation and 36 weeks and 6 days gestation and less than 1 year 
of age at the time of enrollment. 
 
4.2.24 Current suspected or documented developmental disorder, delay, or other developmental 
problem. 
 
4.2.25 Any previous receipt of supplemental oxygen therapy in a home setting. 
 
4.2.26 Known or suspected SARS-CoV-2 exposure within the 14 days prior to enrollment. Note: 
known or suspected SARS-CoV-2 includes a known asymptomatic household member 
under quarantine for SARS-CoV-2 exposure but without a positive SARS-CoV-2 test. 
 
4.3 
Co-Enrollment Considerations 
 
Co-enrollment to any biomedical interventional study is not allowed during the Acute Phase or 
Post-Acute Phase. After the Post-Acute Phase, co-enrollment may be considered if both Protocol 
Teams agree. 
 
Note: co-enrollment into IMPAACT 2021 is allowable for participants already enrolled in the 
PHACS (Pediatric HIV/AIDS Cohort Study) SMARTT (Surveillance Monitoring for ART 
Toxicities) study.  
 
Co-enrollment into IMPAACT 2021 is allowable for participants already enrolled in IMPAACT 
P1112, provided all eligibility criteria above are met, and the participant must not have received 
P1112 study product in the past 12 months. The P1112 and IMPAACT 2021 teams should be 
queried in each case to confirm (impaact.teamp1112@fstrf.org; impaact.team2021@fstrf.org). 
 
4.4 
Recruitment, Screening, and Enrollment Process 
 
Recruitment will take place at US sites selected on the ability to recruit and enroll children in 
RSV vaccine studies; given IMPAACT sites’ history and familiarity with select populations, this 
will include HIV-exposed, uninfected and/or HIV-unexposed children. Each site will identify the 
specific clinics (e.g., hospital, community, and private pediatric clinics) where recruitment will 
occur as part of the site selection process, which will be reviewed and approved by the Protocol 
Team. All recruitment materials must be reviewed and approved by the applicable IRB. 
 
Study product administration (Day 0) must occur within 42 days of collection of the screening 
sample and ideally on the same day as randomization or, if needed, up to 5 days after 
randomization (see Section 6.2). 
 
The IMPAACT Data Management Center (DMC) Study Enrollment System (SES) will be used 
to assist with tracking screening and enrollment. When informed consent is obtained, a 
participant identification number (PID) will be assigned to the child by the study staff, and a 

 
IMPAACT 2021, FINAL Version 3.0 
Page 41 of 106 
28 April 2022 
study-specific screening number will be obtained through the SES. For children found to be 
eligible, randomization and enrollment will occur upon successful entry of required eligibility 
data into the SES. Successful entry into the SES will generate a study identification number (SID) 
assignment and blinded prescribing information for the study product arm to which the child has 
been randomly assigned; this represents the effective point of enrollment. For potential 
participants who are found to be ineligible for the study, or who do not enroll in the study for any 
reason, an electronic case report form (eCRF) will be entered to record the screening outcome. 
Note that any eligible children living in the same household can be enrolled and will be 
randomized per Section 9.3.1. Refer to Section 9.4 for more information on monitoring 
participant accrual in this study.  
 
4.5 
Participant Retention 
 
Once a child has received study product, study staff will make every effort to retain him or her in 
follow-up for the protocol-specified duration of follow-up, i.e., through the Post-RSV Season 
Study Visit, thereby minimizing potential biases associated with loss to follow-up.   
 
4.6 
Participant Withdrawal or Termination from the Study 
 
Regardless of the participant retention procedures referenced above, parents/guardians of children 
participating in this study may voluntarily withdraw their children from the study at any time. 
Any participant who has received study product will be encouraged to remain in study follow-up 
for the duration of the study even if sample collection is refused.  
 
A participant may withdraw or be terminated from the study early for any of the following 
reasons that occur after randomization: 
 
• 
Withdrawal of consent – applies to a parent/guardian who verbally or in writing 
withdraws consent to participate in the study for any reason. 
• 
Exceedance of the 42-day window from collection of the screening sample to study 
product administration – applies to an illness or other participant-specific reason (see 
Section 6.2 for guidance related to exceedances due to a pause in study accrual). 
• 
Noncompliant with protocol – applies to a parent/guardian who does not comply with 
protocol-specific visits or evaluations on a consistent basis, such that adequate follow-up 
is not possible, and the participant’s safety would be compromised by continuing in the 
study. 
• 
Participant re-locates away from the study site (and it is not possible to continue 
participation at another IMPAACT 2021 site near the participant’s new location) or is 
otherwise determined to be lost-to-follow-up. 
• 
Investigator or designee determines that continued participation in the study would be 
unsafe or otherwise not in the best interest of the participant, after consultation with the 
Protocol Team. 
• 
Other – requires an explanation. 
 
The study may be stopped or canceled by the study investigators, sponsors, IMPAACT, 
government or regulatory authorities, or IRBs/IBCs for any reason.  
 
For any participant who received study product and withdraws or is terminated from the study 
prior to scheduled completion of follow-up, study staff will document the reason for the 
withdrawal or termination in detail and will make every effort to complete final evaluations as 

 
IMPAACT 2021, FINAL Version 3.0 
Page 42 of 106 
28 April 2022 
described in Section 6.9. In the event that the circumstances that led to a participant’s withdrawal 
or termination change (e.g., he or she returns to the study site area after having re-located 
previously), the site investigator or designee should contact the Protocol Team 
(impaact.team2021@fstrf.org) to discuss options for resumption of follow-up. 
 
5 
STUDY PRODUCT CONSIDERATIONS 
 
Site pharmacists should consult the Pharmacy Guidelines and Instructions for DAIDS Clinical 
Trials Networks for standard pharmacy operations. Refer to Figure 1 for an overview of the study 
design and to the Investigator’s Brochures (Ibs) for further information about the study products. 
 
5.1 
Study Products 
 
The products that will be administered in this study are: 
• 
Live Recombinant Respiratory Syncytial Virus RSV ΔNS2/Δ1313/I1314L 106 PFU per 
0.5ml vaccine 
• 
Live Recombinant Respiratory Syncytial Virus RSV 6120/ΔNS2/1030s 105 PFU per 
0.5ml vaccine 
• 
Live Recombinant Respiratory Syncytial Virus RSV 276 105 PFU per 0.5ml vaccine – 
this vaccine arm is closed to further enrollment under protocol V2.0 and V3.0; refer to 
protocol V1.0 for details related to this vaccine 
• 
Placebo for each RSV vaccine will be Lactated Ringer’s Solution for Injection, USP 
(0.5ml) 
 
5.2 
Study Product Regimens 
 
Enrolled study participants will receive a single dose of the indicated vaccine or placebo, 
administered as nose drops within 5 days of randomization. Ideally, the date of randomization 
will be the same as the date of study product administration (see Section 6.2).  
 
5.3 
Study Product Formulation  
 
5.3.1 
Vaccines 
 
The RSV ΔNS2/Δ1313/I1314L vaccine is provided in a sterile 2.0 mL micro tube, each 
containing 0.6 mL of Vaccine (Lot RSV #006A), with a titer of approximately 107.3 PFU/mL. The 
vaccine virus concentrate is diluted to an appropriate dose by designated licensed pharmacy 
personnel to prepare a dose of 106 PFU in a 0.5 mL volume. The vaccine vial is labeled as shown 
below in Figure 3. 
 
The RSV 6120/ΔNS2/1030s vaccine is provided in a sterile 2.0 mL micro tube, each containing 
0.6 mL of Vaccine (Lot RSV #012A), with a titer of approximately 106.0 PFU/mL. The vaccine 
virus concentrate is diluted to an appropriate dose by designated licensed pharmacy personnel to 
prepare a dose of 105 PFU in a 0.5 mL volume. The vaccine vial is labeled as shown below in 
Figure 3. 
 
The RSV 276 vaccine will not be provided under protocol V2.0 or V3.0. Refer to protocol V1.0 
for details related to this vaccine. 
  

 
IMPAACT 2021, FINAL Version 3.0 
Page 43 of 106 
28 April 2022 
Figure 3: Investigational Product Label (Enlarged Sample) 
 
RSV ΔNS2/Δ1313/I1314L Vaccine: 
 
Live Recombinant Respiratory Syncytial Virus 
RSV ΔNS2 Δ1313 I1314L  
VERO GROWN VIRUS VACCINE 
Date: 17OCT2012 
Vial#:XXX 
Lot: RSV #006A 
CAUTION: NEW DRUG LIMITED 
 BY FEDERAL (USA) LAW 
TO INVESTIGATIONAL USE 
Store at –80°C ± 15°C 
Charles River Laboratories, Malvern, PA 
 
RSV 6120/ΔNS2/1030s Vaccine: 
 
Live Recombinant Respiratory Syncytial Virus 
RSV 6120/∆NS2/1030s  
VERO GROWN VIRUS VACCINE 
Date: 29AUG2016 
Vial#:XXXX 
Lot: RSV #012A 
CAUTION: NEW DRUG LIMITED 
 BY FEDERAL (USA) LAW 
TO INVESTIGATIONAL USE 
Store at –80°C ± 15°C 
Charles River Laboratories, Malvern, PA 
 
 
5.3.2 
Diluent for RSV ΔNS2/Δ1313/I1314L and RSV 6120/ΔNS2/1030s 
 
As with protocol V2.0, under protocol V3.0, the diluent for RSV ΔNS2/Δ1313/I1314L and RSV 
6120/ΔNS2/1030s is Lactated Ringer’s Solution for Injection, USP.  
 
5.3.3 
Placebo for RSV ΔNS2/Δ1313/I1314L and RSV 6120/ΔNS2/1030s 
 
As with protocol V2.0, under protocol V3.0, the placebo for RSV ΔNS2/Δ1313/I1314L and RSV 
6120/ΔNS2/1030s is Lactated Ringer’s Solution for Injection, USP.  
 
5.4 
Study Product Storage 
 
Vaccine will be stored in a secure freezer under pharmacy control at -80°C ±15°C. It must remain 
frozen until time of use. Once the vaccine is thawed, it should never be refrozen for reuse. 
Vaccine will be prepared from new, unopened containers for each use.  
 
Lactated Ringer’s Solution for Injection, USP should be stored at room temperature in accordance 
with the manufacturer’s recommendation and transferred to a secure 2°C to 8°C refrigerator at 
least 24 hours before use. Vaccine diluent/placebo will be prepared from new, unopened 
containers for each use. 
 
Procedures for managing the vaccine and diluent/placebo shipment are in the Manual of 
Procedures (MOP). 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 44 of 106 
28 April 2022 
5.5 
Study Product Preparation 
 
The diluent for the vaccines, the placebo for the vaccines, and the RSV vaccines must be prepared 
by following the detailed instruction in the MOP. 
 
Prior to study product administration, an authorized prescriber will supply a prescription to the 
pharmacy. The prescription must include the information outlined in the MOP. Designated 
licensed pharmacy personnel will prepare the correct dose of vaccine or placebo for each 
participant in a USP <797> compliant environment appropriate for the Biosafety Level of the 
study products, as determined by local policies and procedures. To preserve blinding, yellow 
overlays will be applied to all prepared syringes. 
 
5.5.1 
Preparation of Placebo for RSV ΔNS2/Δ1313/I1314L and RSV 6120/ΔNS2/1030s 
 
As with protocol V2.0, under protocol V3.0, placebo for RSV ΔNS2/Δ1313/I1314L and RSV 
6120/ΔNS2/1030s will be Lactated Ringer’s Solution for Injection, USP. The diluent/placebo 
must be kept on ice during preparation of vaccine products. 
 
Placebo will be drawn up to a volume of 0.5 mL in a sterile 1 mL oral syringe and labeled per 
instructions in MOP. An auxiliary label stating “FOR INTRANASAL ADMINISTRATION 
ONLY” will be affixed to the syringe or outside bag. The labeled, filled syringe(s) will be 
transported in a cooler with a closed lid, monitored and maintained at 2ºC to 8ºC with ice or cold 
packs, to the clinical site for administration. Placebo must be administered within 4 hours of the 
time Lactated Ringer’s Solution for Injection, USP is removed from the refrigerator.  
 
Please follow the MOP for detailed instructions on preparation of placebo. 
 
5.5.2 
Preparation of Live Recombinant Respiratory Syncytial Virus RSV ΔNS2/Δ1313/I1314L and 
RSV 6120/ΔNS2/1030s 
 
If the -80°C freezer where the RSV vaccines are stored is not in close proximity to where the 
preparation is being done, the vaccine vials should be transported on dry ice from the freezer 
to the aseptic preparation area. Do not thaw this product on the bench top or allow the vial to 
thaw completely before putting onto wet ice. RSV is extremely sensitive to temperature 
fluctuations. Please follow the MOP for proper handling of the study product.  
 
RSV ΔNS2/Δ1313/I1314L requires two vials of undiluted vaccine to prepare the vaccine dose. 
RSV 6120/ΔNS2/1030s requires three vials of undiluted vaccine. Refer to the MOP for 
additional guidance. When manipulating the undiluted vaccine, use as small a gauge needle as 
possible to avoid loss of vaccine in the needle and syringe hub. As with protocol V2.0, under 
protocol V3.0, the frozen vaccine will be thawed and diluted with Lactated Ringer’s Solution for 
Injection, USP to the indicated dose of either 106 (RSV ΔNS2/Δ1313/I1314L) or 105 PFU (RSV 
6120/ΔNS2/1030s) in 0.5 mL prior to administration.  
 
The diluted vaccine will be drawn up to a volume of 0.5 mL in a sterile 1 mL oral syringe and 
labeled per instructions in MOP. An auxiliary label stating “FOR INTRANASAL 
ADMINISTRATION ONLY” will be affixed to the syringe or outside bag. The labeled, filled 
syringe(s) will be transported in a cooler with a closed lid, monitored and maintained at 2ºC to 
8ºC with ice or cold packs, to the clinical site for administration. Vaccine must be prepared 
and administered within 4 hours of being removed from the freezer and thawing. However, 

 
IMPAACT 2021, FINAL Version 3.0 
Page 45 of 106 
28 April 2022 
the expiration time is assigned based on the time the Lactated Ringer’s Solution for 
Injection, USP is removed from the refrigerator in order to maintain the blind. 
 
After the designated licensed pharmacy personnel dilutes the vaccine and draws up the vaccine 
into a syringe for administration, he/she will remove the label from all vaccine vials and place it 
in the accountability log. Please see the IMPAACT 2021 MOP for the study preparation and 
accountability documents. In this manner, monitoring personnel will be able to verify the 
accountability of all vaccine vials used for the study. 
 
Samples of undiluted (if available) and diluted vaccine will be aliquoted from the vaccine 
remaining after vaccine has been prepared and delivered to the clinical staff. The samples will 
be snap frozen as per the MOP and stored at -80°C ±15°C in the investigational pharmacy but 
separate from the study product until they are shipped to the central laboratory for titration. 
Titration of vaccine is done to confirm the titer of the vaccine administered to the participants. 
To “snap freeze” diluted and undiluted vaccine aliquots, follow CoolBox procedures described 
in the MOP. 
 
Please follow the MOP for detailed instructions on vaccine storage, handling, preparation, 
labelling and transport to the clinic. 
 
5.6 
Study Product Administration Procedure 
 
All study participants will receive a single dose of study product, administered as nose drops. 
There is no nasal preparation prior to administration. While the participant is supine, a volume of 
0.5 mL of study product will be delivered as nose drops (approximately 0.25 mL per nostril) 
using a sterile, needle-less 1 mL oral syringe. Participant will remain supine for approximately 60 
seconds following study product administration. 
 
5.7 
Study Product Acquisition 
 
The clinical lots of RSV ΔNS2/Δ1313/I1314L and RSV 6120/ΔNS2/1030s (and previously RSV 
276 under protocol V1.0) were generated by Charles River Laboratories using the seed virus 
provided by the National Institutes of Health (NIH).  
 
Lactated Ringer’s Solution for Injection, USP will be used as the diluent and placebo. 
 
Upon successful completion of protocol registration procedures, the clinical research site (CRS) 
pharmacists can order the vaccine, diluent/placebo, sterile oral 1-mL syringes (commercially 
available, individually packaged), sterile syringe caps and yellow overlays from the CRPMC by 
following the instructions in Pharmacy Guidelines and Instructions for DAIDS Clinical Trials 
Networks.  
 
Please refer to the MOP for details on shipment of the study products. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 46 of 106 
28 April 2022 
5.8 
Study Product Accountability 
 
The site pharmacist is responsible for maintaining an accurate inventory and accountability record 
of vaccine and diluent/placebo supplies for this study. The vaccines will be prepared as instructed 
with the site pharmacist serving as the unblinded dispenser. A copy of the randomization code 
will be retained by the site pharmacist. The site pharmacist will be responsible for maintaining the 
blind, and pharmacy records will be maintained in the pharmacy only.  
 
5.9 
Disposition of Used Study Product 
 
If there is any vaccine left after the syringes have been drawn up and aliquots have been removed 
for titering, it will be destroyed by pharmacy personnel as per the MOP. Partially used vials of 
vaccine and diluent/placebo may not be saved and reused at a later time. 
 
5.10 
Final Disposition of Study Products 
 
All unused study products must be returned to the CRPMC after the study is completed or 
terminated, unless otherwise instructed by the Protocol Team. Procedures and relevant forms are 
provided in the Pharmacy Guidelines and Instructions for DAIDS Clinical Trials Networks. 
 
5.11 
Concomitant Medications 
 
The term concomitant medications is used in this study to refer to medications other than the 
study products listed in Section 5.1. Additional guidance regarding concomitant medications is 
provided below and in Table 5. 
 
5.11.1 Prohibited Concomitant Medications 
 
The use of the following is not permitted:  
 
• 
Prophylactic antipyretics, decongestants, or antihistamines during the Acute Phase (28 
days following study product administration) – note that use of these medications for 
treatment of symptoms is allowed 
• 
An investigational drug or investigational vaccine other than the study product within 56 
days after receiving study product 
 
5.11.2 Precautionary Concomitant Medications  
 
 
Due to their potentially confounding effect on immunogenicity results, the following treatments 
should be avoided after study product administration unless clinically indicated:  
 
• 
Systemic corticosteroids for more than 14 days at a dosage equivalent to prednisone at >2 
mg/kg or 20 mg daily or other immune-modifying drugs  
• 
Immunoglobulins and/or any blood products  
 
The following should be avoided after study product administration unless indicated in an 
outbreak setting: 
 
• 
Licensed inactivated vaccine or live-attenuated rotavirus vaccine within 14 days after 
receiving study product  

 
IMPAACT 2021, FINAL Version 3.0 
Page 47 of 106 
28 April 2022 
• 
Licensed live virus vaccine, other than rotavirus vaccine, within 28 days after receiving 
study product 
 
Please notify the PSRT via email at impaact.psrt2021@fstrf.org if any of the concomitant 
medications listed above are administered. 
 
6 
STUDY VISITS AND PROCEDURES 
 
Study visits, except study product administration, may be conducted at one of the clinical sites or 
as home visits. Some Illness Visits may be performed at the clinical site, in-person or via 
telehealth (telephone or video), or in the community by a licensed medical provider. Study 
product administration must be conducted at one of the clinical sites. 
 
An overview of the study visits, evaluation schedule, and specimen collection and volumes are 
provided in Appendix I and II. Presented in this section is additional information on visit-specific 
study procedures. Study timeframes are summarized in Figure 2 of Section 3. 
 
If necessary, blood draws may occur on a different day than other visit procedures within the 
allowable window for that visit. All visits and procedures must be documented in accordance 
with NIAID Division of AIDS (DAIDS) requirements for source documentation; refer to Section 
10 for more information on documentation requirements and completion of eCRFs. Refer to 
Section 7 for information on expedited adverse event (EAE) reporting, which is required at 
specified times during follow-up.   
 
In addition to the protocol-specified procedures listed in this section, study staff may complete 
other tasks consistent with site SOPs, including but not limited to collecting, reviewing, and 
updating demographic and locator information; reviewing elements of informed consent; 
scheduling telephone contacts and visits; providing instructions for contacting study staff between 
visits; providing visit reminders; and following up on missed visits. All such tasks should be 
documented consistent with site SOPs. Clinical evaluations must be performed by a medical 
professional. Study staff should inform participants’ parents/guardians of clinically meaningful 
physical exam findings and laboratory test results when available. 
 
For sites experiencing disruptions or limitations of usual operations due to COVID-19, 
operational guidance is provided in Appendix VAppendix VAppendix V. All sites should follow 
applicable government, health authority, and institutional policies with respect to conduct of 
study visits and procedures, with utmost importance placed on the health and well-being of study 
participants and study staff. 
 
6.1 
Screening Visit 
 
Screening may begin 14 days prior to the start of the enrollment period. As sites consider 
scheduling for the screening visit, it is important to also consider potential dates of 
randomization, given that study product administration cannot occur 42 days or more after the 
screening sample is collected. Sites should schedule randomization and study product 
administration to be as soon as feasible after screening, allowing for the turnaround time for the 
RSV serology testing. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 48 of 106 
28 April 2022 
The parent/guardian must complete the informed consent process and sign the informed consent 
form before any study-related procedures are performed. Parents/guardians will also be offered a 
signed copy of the informed consent form (see Section 12.3). 
 
As in previous Phase I trials of other live-attenuated RSV vaccines (15, 25-27), screening 
laboratory tests other than the RSV antibody will not be performed on potential participants. Such 
tests are not routinely performed as part of well-child care, given that the risk of undiagnosed 
hepatic, metabolic, and renal diseases is much lower in children than in adults (33).  
 
Screening Visit Procedures*  
Administrative 
and Regulatory 
• Obtain written informed consent per IRB-approved procedures (a 
separate screening ICF may be used at some sites) 
• Confirm parent/guardian’s informed consent comprehension using 
the template quiz provided in the MOP or other, site-specific 
method.  
• Assign participant identification number (PID) 
• Assess eligibility 
Clinical 
• Obtain available medical records, including immunization record.  
If necessary, obtain release of medical records from 
parent/guardian to review the potential participant’s medical record 
as required per Health Insurance Portability and Accountability Act 
(HIPAA). 
• Obtain medical history, which should include demographics, prior 
diagnoses, current medications, signs and symptoms, and 
developmental status. 
• Perform focused clinical examination including temperature, heart 
rate, respiratory rate, EENT, lung, heart, and lymph nodes. 
Note: if the potential participant has had a physical examination in 
the past 2 weeks as part of routine care, some or all of the clinical 
examination data may be abstracted from the medical record (i.e., 
the procedures would not need to be repeated at the screening 
visit). 
Laboratory 
Blood  
Collect blood for: 
• Screening and pre-study product administration blood draw for 
RSV serum antibody testing. Note: if the potential participant had 
been screened but not enrolled into any study of an RSV vaccine 
developed by the LID (NIAID, NIH), the results from the sample 
collected for that study may be used if the sample was collected 
within the 42-day enrollment window for IMPAACT 2021; it is not 
necessary to collect another sample. 
Study Product 
Not applicable 
Schedule Enrollment Visit 
Note that study product administration must be no more than 42 days 
after collection of the screening sample and within 5 days of 
randomization.  
*No more than 42 days prior to study product administration. 
 
6.2 
Enrollment Visit/Study Product Administration (Day 0) 
 
Study enrollment and study product administration (Day 0) must occur outside the time during 
which wt RSV circulates in the community at each study site, and after: 
• 
the screening sample confirms that the child is RSV-seronegative, and 
• 
he/she meets all other inclusion/exclusion criteria.  
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 49 of 106 
28 April 2022 
Day 0 will correspond to the day of study product administration. Whenever possible, study 
product administration (Day 0) is to occur on the same day as randomization. Although sites are 
allowed up to 5 days after randomization to complete the Enrollment Visit and administer study 
product, sites should not proceed to randomization until a) final eligibility determination has been 
confirmed and b) it has been confirmed that study product can be administered within this 
window. If these 2 conditions cannot be met, randomization should be postponed. 
 
If participant is randomized and subsequently noted to have any of the following, study product 
administration must be deferred: 
• 
fever (rectal temperature of ≥100.4°F (38°C)), or  
• 
upper or lower respiratory symptoms or signs (including but not limited to rhinorrhea, 
cough, or pharyngitis), or 
• 
nasal congestion significant enough to interfere with successful study product 
administration, or  
• 
otitis media 
 
All eligible children from the same household who are enrolled on the same date must receive 
study product on the same date. Therefore, if one child experiences any of the illnesses above, 
study product administration must be deferred for all children in the household who were enrolled 
on the same date.   
 
Note: if the study product administration (Day 0) is deferred for one of the reasons above but then 
cannot be completed within 5 days of randomization, the participant(s) must be terminated from 
the study. These participants will not be replaced.   
 
If the 42-day window from collection of the screening sample to study product administration is 
exceeded due to an illness or other participant-specific reason and a child has already been 
randomized, the child must be taken off study. If the 42-day window from collection of the 
screening sample to study product administration is exceeded due to a pause in accrual, and a 
child whose parents wish to continue study participation has already been randomized, the child 
will be re-screened to confirm eligibility and remain in the originally assigned study arm. Email 
the PSRT at impaact.psrt2021@fstrf.org if the participant’s parent/guardian and the site still wish 
for the child to participate in the study. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 50 of 106 
28 April 2022 
Enrollment Visit/Day 0 Procedures   
Must be completed no more than 42 days from collection of the screening sample and within 5 
days of randomization  
Administrative 
and Regulatory 
• Complete eligibility determination and confirmation*  
• Complete paper-based eligibility checklist*, enter checklist 
data into SES to enroll/randomize the child, print and file a 
copy of the confirmation file 
Clinical 
• Obtain interim history, including any changes in medications 
and immunizations  
• Clinical examination: 
o Perform complete physical examination including 
temperature, heart rate, respiratory rate, weight, length 
and assessment of HEENT [head, ears, eyes, nose, 
throat], lungs, heart, abdomen, musculoskeletal, age-
appropriate neurological and skin exam. 
o Record temperature, pulse, and respirations 
Note: Confirm eligibility including clinical examination prior to 
administering study product. 
Laboratory 
Blood  
If insufficient volume collected at screening, collect blood: 
• To ensure that back-up aliquot is available for comparing pre- 
and post- sera.  
Study Product 
• Prescribe and prepare/dispense study product 
• Administer study product and maintain participant in a supine 
position for 1 minute. 
• Observe for at least 30 minutes after study product 
administration to evaluate for immediate hypersensitivity 
reactions. 
Prepare for follow-up 
• Provide the following: temperature card/memory aid with 
explanation, temporal and rectal thermometers with instructions 
for use, illness criteria explanation, and study personnel contact 
information. Schedule non-visit contacts for Days 1-27; 
schedule in-person Day 28 visit. 
• Provide instructions on how to collect, store, and return a nasal 
swab sample and dispense collection supplies.   
*Perform prior to enrollment/randomization 
 
Following the Enrollment Visit, the parent/guardian will record the child’s temperatures and signs 
of illness on the temperature card/memory aid and provide these to study personnel during an in-
person visit or non-visit day phone, email, or text contact. New rectal thermometers will be given, 
and temporal artery thermometers will be provided to parents/guardians for use during the study. 
For temperature measurements, parents/guardians will be instructed to use the study-provided 
temporal artery thermometer to screen for elevated temporal artery temperatures. This device is 
used to minimize the number of rectal temperature measurements and has been shown to be an 
effective screening tool for rectal fever (34). The parent/guardian will measure temporal artery 
temperatures following the manufacturer’s directions. If any temporal artery temperature is 
≥100.0°F, parents/guardians will be asked to measure a rectal temperature within 20 minutes (34). 
For study-specific management of solicited AEs and grading of temperatures, see Section 7.2 and 
Table 7, respectively. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 51 of 106 
28 April 2022 
6.3 
Acute Phase Contacts and Visit 
 
Refer to Figure 1 for a timeline of study procedures. The Acute Phase begins with study product 
administration (Day 0) and ends at midnight on the 28th day after study product administration. 
During the Acute Phase of the study, a study physician, physician assistant, nurse practitioner, or 
study nurse will be available by telephone 24 hours a day for consultation with parents/guardians 
regarding any illnesses that may occur during this period. 
 
Study personnel will have daily contact with participants’ parents/guardians for the first 28 days 
after study product administration. This 28-day period is consistent with the duration of shedding 
of live-attenuated respiratory virus vaccines in RSV-seronegative children (34-37).  
 
Study staff will contact the parent/guardian daily on Days 1-27 and will record parent/guardian-
provided temperatures and signs of illness; in-person visit will be conducted on Day 28 as 
outlined below. Participants with illness may have Illness Visits to assess the severity of the 
illness (see Section 6.8 for Illness Visits).   
 
6.3.1 
Acute Phase Contacts: Daily on Study Days 1-27 (±1 day)  
 
The non-visit contacts during the Acute Phase will be conducted via phone, email, or text contact.   
 
If the parent reports symptoms suspicious for an LRI, otitis media, fever or URI (per Appendix 
III), then an Illness Visit should be scheduled (see Section 6.8).  
 
Days 1-27 Daily Contact Procedures (each contact from day of study product administration ±1 
day) 
Interim History 
• Obtain and document from parent/guardian the participant’s 
interim history since last contact, including any changes in 
medications and immunizations.   
• Document highest temperature (temporal or rectal) 
Prepare for follow-up 
• Address any concerns and schedule appointment if necessary. 
 
6.3.2 
Acute Phase Visit: Study Day 28 (-1/+4 days) 
 
An in-person study visit during the Acute Phase is scheduled to be conducted on Day 28 (-1/+4 
days). If an in-person visit occurs on a date other than the target date within the allowable 
window, then non-visit contact is conducted in place of the original target visit date.   
 
Events that took place through midnight of Day 28 are considered to have occurred during the 
Acute Phase and will be reported on the non-visit contact conducted on Day 29. Note that it is not 
necessary to also have a “Day 29” contact (Section 6.4.1) if the Day 28 Visit is conducted on or 
after Day 29. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 52 of 106 
28 April 2022 
Day 28 (-1/+4 days) Visit Procedures (visit from day of study product administration) 
Clinical 
• Obtain interim history, including any changes in medications 
and immunizations 
• Perform focused clinical examination including temperature, 
heart rate, respiratory rate, EENT, lung, heart, and lymph 
nodes. 
• Record temperature, pulse, and respirations.   
Laboratory 
 
Blood 
 
Collect blood for: 
• Serum antibodies to RSV 
Prepare for follow-up 
• Schedule non-visit day contact and follow-up in-person visits.  
• Review serious AE criteria with participants and how to contact 
study personnel during Post-Acute Phase (Study Day 29 
through Day 56). 
 
If the child is diagnosed as having an LRI, otitis media, fever, or URI (per Appendix III) during 
the Acute Phase, evaluations required for the Illness Visit need to be performed. See Section 6.8 
for expectations regarding timing and requirements for in-person versus telehealth Illness Visits. 
If illness criteria are met or suspected (Appendix III), an Adventitious Agent Assay will be 
performed on the Illness Visit nasal swab (see MOP and LPC).    
 
6.4 
Post-Acute Phase (Days 29 to 56) 
 
The Post-Acute Phase begins at 12:01 am on the 29th day after study product administration and 
ends at midnight on the 56th day after study product administration. During the Post-Acute Phase, 
parents/guardians will be instructed to monitor for and contact the study site if their child has 
symptoms that are suggestive of a Serious Adverse Event (serious AE). If the parent/guardian 
reports a serious AE that may meet the study pause or stop criteria (Section 9.4.2), then an Illness 
Visit should be scheduled (see Section 6.8).  
 
6.4.1 
Day 29 Contact (+1 day) 
 
There will be a non-visit contact on Day 29 to obtain interim history through midnight on the 28th 
day following study product administration. If the Day 28 Visit is conducted on or after Day 29, it 
is not necessary to have an additional non-visit contact with the family. 
 
Day 29 Contact Procedures (+1 day) 
Interim History 
• Obtain interim history through midnight of the 28th day following 
study product administration, including any changes in 
medications and immunizations 
• Document highest temperature (temporal or rectal) 
Prepare for follow-up 
• Address any concerns. 
• Review serious AE criteria with participants and how to contact 
study personnel during Post-Acute Phase (Day 29 through Day 
56). 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 53 of 106 
28 April 2022 
6.4.2 
Day 56 Visit (+7 Days) 
 
The Day 56 Visit should be conducted between 56 and 63 days following study product 
administration. Because the Post-Acute Phase ends as of midnight on the 56th day following study 
product administration, only events through that time should be evaluated as having occurred 
during the Post-Acute Phase. If the Day 56 Visit is conducted on the 56th day after study product 
administration, sites should arrange a non-visit contact the next day to confirm that there were no 
events between the time of the study visit and midnight of the 56th day after study product 
administration. The evaluations expected at this visit are outlined below.  
 
Day 56 Visit (from day of study product administration +7 days) 
Clinical 
• Obtain interim history since last contact, including any changes in 
medications and immunizations  
• Record temperature, pulse, and respirations.  
Laboratory 
 
Blood 
 
Collect blood for: 
• Serum antibodies to RSV 
 
Prepare for follow-up 
• Review plans for weekly contact during the RSV Season 
Surveillance Period (see Section 6.6). 
 
 
6.5 
Period after Day 56 Visit until October 31st or as specified in the MOP 
 
During this period, contact with the participant is not required. No clinical data will be entered 
into eCRFs or reported under this protocol except for data as outlined in Table 5 in Section 7.2. 
 
6.6 
RSV Season Surveillance (November 1st through March 31st following study product 
administration or as specified in the MOP) 
 
Based on previous data regarding the seasonality of RSV in the Baltimore, MD area (Appendix 
IV), surveillance for RSV-associated disease will be conducted during the RSV season that starts 
in the calendar year of each participant’s study product administration. RSV season is between 
November 1st and March 31st for most sites or—for sites with local RSV seasons that differ—as 
specified on a site-by-site basis in the MOP. Note, RSV Season Surveillance may overlap with 
the Study Acute and Post-Acute Phase. In this case, evaluations required for each of the relevant 
phases of the study will be conducted.  
 
During the RSV season that starts in the calendar year of study product administration, 
participants enrolled in this study will be monitored for symptomatic, medically attended, RSV-
like illnesses listed below. Medically attended events during the RSV Season Surveillance Period 
are those for which care is sought in person or through formal telehealth (telephone or video) 
visits conducted by study staff or other medical provider; a telephone call to a nurse line is not 
considered medically attended. Information about these illnesses will be obtained during the 
RSV Season Surveillance Period by weekly communication between study personnel and the 
participant’s parent/guardian. These contacts may be by telephone, email, or text contact or by 
in-person visit. For this period, determine if any of the following medically attended events 
occurred. Please note that the symptoms below do not need to meet the Appendix III criteria. 
o Medically attended fever 
o Medically attended upper respiratory illness  
o Medically attended otitis media 

 
IMPAACT 2021, FINAL Version 3.0 
Page 54 of 106 
28 April 2022 
o Medically attended lower respiratory illness  
 
Study staff should conduct an Illness Visit within 3 days of a site’s study staff notification of any 
of these events; note that the Illness Visit can be conducted by a licensed provider in the 
community only if medical records for the medically attended event are available to the site (see 
Section 6.8).    
 
RSV Season Surveillance contacts (November 1st* through March 31st following study product 
administration) 
Clinical 
• Obtain interim history, including any changes in medications and 
immunizations 
Prepare for follow-up 
• Continue with weekly contacts through March 31st  
• Schedule an Illness Visit if warranted (see Section 6.8) 
• Schedule Post-RSV Season Study Visit to take place between April 
1st and 30th in the calendar year following study product 
administration 
*This date applies to most sites but may differ for those with local RSV seasons that differ. 
 
6.7 
Post-RSV Season Study Visit (April 1st to 30th in the calendar year following study product 
administration) 
 
There will be a single in-person visit between April 1st and 30th in the calendar year following 
study product administration. This window applies to all sites. For sites experiencing disruptions 
or limitations of usual operations due to COVID-19, operational guidance related to this visit 
(including broadened visit window specifications) is provided in Appendix V. 
 
Post-RSV Season Study Visit (April 1st to 30th in the calendar year following study product 
administration) 
Laboratory 
 
Blood 
 
Collect blood for: 
• Serum antibodies to RSV 
 
6.8 
Illness Visit 
 
The timeframe after site notification in which the Illness Visit must occur depends on grading of 
the fever and respiratory symptoms per Section 7.3.3 and Appendix III and the phase of the study. 
Following an Illness Visit, sites should continue to follow participants until resolution of 
symptoms. Refer to the MOP for guidance regarding additional Illness Visits for the same illness.  
 
Illness Visits may be conducted by study staff or, alternatively, by other medical providers if 
medical records from the visit can be made available to study staff and a parent/guardian can 
collect the nasal swab sample.   
 
All Illness Visits require nasal swab collection, which can be performed by study staff or by 
parents/guardians, if they are comfortable collecting. If a participant experiences an illness that 
may meet protocol-specified pausing/stopping rules (see Section 9.4.2), and parent/guardian 
collected the nasal swab, study staff should rapidly retrieve swab. See MOP and LPC for 
additional guidance on collection, storage, and return of the nasal swab samples.   

 
IMPAACT 2021, FINAL Version 3.0 
Page 55 of 106 
28 April 2022 
  
Illness Visits may occur during any of the following phases of the study: 
• 
Acute Phase:  
o For Grade 1 otitis media or URI (except rhinorrhea without cough), an in-person 
Illness Visit must be conducted within 3 days after illness onset.  
o For rhinorrhea without cough or for fever <Grade 2, the Illness Visit may be 
performed via telehealth (telephone or video) rather than in-person, if a 
parent/guardian can collect nasal swab sample at home.    
o For Grade 2 or higher fever, otitis media, or URI (except rhinorrhea without cough), 
an in-person Illness Visit must be conducted within 2 days after illness onset.  
o For a possible LRI, with any grade, the initial in-person assessment will occur within 
1 day of the reported onset of the LRI. A follow-up assessment (in person or via 
telehealth (telephone or video)), including nasal swab, is required 1 to 3 days after the 
initial assessment.  
• 
Post-Acute Phase: For a serious AE that may meet the study pause or stop criteria 
(Section 9.4.2), an in-person Illness Visit must be conducted within 3 days of site 
notification. As noted above, the in-person visit can be performed by study staff or, 
alternatively, by another medical provider if medical records from the visit can be made 
available to study staff and a parent/guardian can collect the nasal swab sample.   
• 
RSV Season Surveillance Period (between November 1st and March 31st for most sites 
or—for sites with local RSV seasons that differ—as specified on a site-by-site basis in 
the MOP): A nasal swab should be collected as outlined below (by parent/guardian or by 
study staff) within 3 days of site notification of a medically attended illness (as defined in 
Section 6.6) of the following types: fever, URI, LRI or otitis media.  
o If study staff can obtain the medical records for the medically attended visit, the 
medical records can be used in lieu of an Illness Visit, with parent/guardian collection 
of a nasal swab within 3 days of notification of the event. However, if this phase 
overlaps with the Acute or Post-Acute Phases, the time frames specified for the 
relevant Acute or Post-Acute phase should be used. 
o If obtaining medical records is not possible, study staff should conduct an in-person or 
telehealth (telephone or video) Illness Visit within 3 days of notification of the event. 
However, if this phase overlaps with the Acute or Post-Acute Phases, the time frames 
specified for the relevant Acute or Post-Acute phase should be used. 
 
Illness Visit Procedures 
Clinical 
• Obtain interim history, including any changes in medications and 
immunizations, and request release of medical records, if available, 
from non-study visit(s) related to the event prompting the Illness 
Visit. 
• If an in-person visit is conducted per Section 6.8, perform focused 
clinical examination including temperature, heart rate, respiratory 
rate, EENT, lung, heart, and lymph nodes. 
• If an in-person visit is conducted per Section 6.8, or if using 
medical records, record temperature, pulse, and respirations.   
Laboratory 
 
Nasal Swab 
Collect nasal swab for: 
• Viral detection and quantification 
• If a participant experiences an illness that may meet protocol-
specified pausing/stopping rules (see Section 9.4.2) and 
parent/guardian collected nasal swab, study staff should make 
plans to rapidly retrieve swab. 
Prepare for follow-up 
• Schedule follow-up as appropriate 

 
IMPAACT 2021, FINAL Version 3.0 
Page 56 of 106 
28 April 2022 
 
 
6.9 
Early Discontinuation Study Visit 
 
In the event that a participant is unable to continue participation in the study, every effort should 
be made to schedule a final Early Discontinuation Visit. Participants who discontinue prior to 
study product administration are not required to complete an Early Discontinuation Visit. 
 
Early Discontinuation 
Clinical 
• Obtain interim history, including any changes in medications 
and immunizations   
Laboratory 
 
Blood 
 
Collect blood for: 
• Serum antibodies to RSV 
 
6.10 
Additional Considerations for Laboratory Procedures 
 
Each study site and laboratory involved in this study will comply with the DAIDS policy on 
Requirements for DAIDS Funded and/or Sponsored Laboratories in Clinical Trials Policy, which 
is available at:  
https://www.niaid.nih.gov/research/daids-clinical-research-laboratory-specimens-management 
 
6.10.1 Specimen Collection 
 
Specimens will be collected for this study as indicated in the Schedule of Evaluations and per 
detailed guidance provided in the Laboratory Processing Chart (LPC), which will be available on 
the IMPAACT web site: www.impaactnetwork.org. Further information on collection of blood 
and nasal swab specimens will also be provided in the MOP. 
 
In accordance with US National Institutes of Health (NIH) recommendations, pediatric blood 
collection will not exceed 5 mL/kg in a single day or 9.5 mL/kg in any eight-week period. See 
Appendix I and II for specific blood volumes for IMPAACT 2021. Blood volumes of 5 mL are 
required for serology assays. This is the minimal required volume to determine the antibody 
response to the vaccines by the “gold standard” RSV plaque reduction neutralization assay, and 
by RSV glycoprotein ELISAs.  
 
Virus Detection 
 
Nasal swab specimens for detection of RSV and adventitious respiratory viruses by rRT-PCR 
(and culture when possible) will be collected from participants who meet illness criteria during 
the initial phase (Day 0 through Day 56) and RSV Season Surveillance Period (November 1st – 
March 31st for most sites or—for sites with local RSV seasons that differ—as specified on a site-
by-site basis in the MOP). Laboratory testing will be performed by personnel that are not 
involved with clinical assessment to maintain the blinding of the study. 
 
6.10.2 Specimen Preparation, Testing, Storage, and Shipping 
 
All specimens collected for this study will be labeled, transported, processed, tested, stored and/or 
shipped in accordance with the DAIDS policy referenced in Section 6.10, site and local 
laboratory SOPs, and the LPC. The frequency of specimen collection and testing will be directed 
by the Schedule of Evaluations (Appendix I and II). The Laboratory Data Management System 

 
IMPAACT 2021, FINAL Version 3.0 
Page 57 of 106 
28 April 2022 
(LDMS) will be used to document specimen collection, testing, storage, and shipping as specified 
in LPC.  
 
Virologic and Immunologic Assays 
 
Serum specimens will be collected up to 42 days prior to study product administration for the 
screening prior to study product administration, and at the Day 28 and Day 56 Visits for 
measurement of serum antibodies to RSV. In addition, post-RSV season serum specimens will be 
collected. These later samples will be used to determine whether a 2.5-fold or greater rise in 
RSV-specific serum antibody titer has occurred during the RSV season, which would signify 
infection with wt RSV. This will allow comparison of the rate and severity of significant RSV 
illness following infection with wt virus, as well as comparison of the antibody responses in 
vaccine and placebo recipients. Screening serum samples will be rapidly shipped to JHU for 
measurement of RSV-neutralizing antibody. All other sera will be shipped to JHU as specified 
in the MOP. 
 
Nasal swab specimens collected during Illness Visits will be used for quantitation of the amount 
of vaccine virus shed by quantitative reverse-transcription PCR. These assays, as well as the 
assessment of nasal swabs for the presence of adventitious viral agents, will be performed at the 
Johns Hopkins University Center for Immunization Research (JHU CIR). Cytokine/chemokine 
assays may also be performed on nasal washes from participants (enrolled under protocol V1.0) 
infected with vaccine virus if sufficient material is available. Selected specimens may be sent to 
LID, NIAID for confirmatory testing.  
 
If a participant experiences an illness meeting protocol-specified pausing/stopping rules, nasal 
swab specimens from the Illness Visit will be rapidly shipped to JHU for testing for adventitious 
agents by PCR; in this scenario, if parent/guardian collected a nasal swab, study staff should 
rapidly retrieve the specimen.  
 
Plan for Future Use and Storage of Biological Samples 
 
All specimens collected as part of this study may, with the parent/guardian’s permission, be 
stored for future research as part of JHU CIR’s approved biospecimen repository for vaccine 
research or at the LID, NIAID. These samples may be used for future screening for respiratory 
virus vaccine studies and to learn more about RSV infection and other diseases. These samples 
will not be sold or used to make commercial products. Samples will be stored only with the 
parent/guardian’s permission.  
 
All samples stored in the repository will be labeled with the participant identification (PID) 
numbers that, by themselves, cannot identify study participants but are linkable to the study 
databases generated by the main study. The repository database will contain only the study 
participants’ PID numbers. A master log linking the study participants’ PID numbers is 
maintained at the individual enrolling site and will not be shared with the Protocol Team or the 
laboratory at the JHU CIR. Study participants, or their parents/guardians, may withdraw consent 
for future testing of their specimens at any time. 
 
In the future, other investigators (both at NIH and outside) may wish to study these samples 
and/or data. In that case, IMPAACT and LID approval must be sought prior to any sharing of 
samples and/or data/clinical information. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 58 of 106 
28 April 2022 
6.10.3 Biohazard Containment 
 
Sites will use local standards to guide the use of personal protective equipment when collecting 
nasal swabs. As the transmission of blood-borne pathogens can occur through contact with 
contaminated needles, blood, and blood products, appropriate blood and secretion precautions 
will be employed by all personnel in the drawing of blood and shipping and handling of all 
specimens for this study, as currently recommended by the Centers for Disease Control and 
Prevention and the National Institutes of Health. Additional specimen collection and processing 
precautions are included in the MOP. All infectious specimens will be transported using 
packaging mandated in Title 42 of the Code of Federal Regulations, Part 72 (42 CFR 72) and in 
accordance with individual carrier guidelines (e.g., Federal Express, Airborne Express). 
 
7 
SAFETY ASSESSMENT, MONITORING, AND REPORTING 
 
Participant safety will be carefully assessed, monitored, and reported at multiple levels 
throughout this study. Sections 7.1-7.3 describe safety-related roles, responsibilities, and 
procedures for site investigators. The safety monitoring roles of the Protocol Safety Review Team 
(PSRT) and the Data and Safety and Monitoring Board (DSMB) are briefly referenced in Section 
7.1 and described in detail in Section 9.4. For this study, the DSMB will include two to three 
subject matter experts (i.e., ad hoc DSMB Expert Members) with expertise in pediatric 
respiratory virus vaccine development.  
 
7.1 
Safety-Related Roles and Responsibilities 
 
7.1.1 
Site Investigators 
 
Site investigators are responsible for continuous monitoring of all study participants and for 
alerting the Protocol Team if unexpected concerns arise. Site investigators will enter safety-
related data into eCRFs as indicated in Section 7.2 and complete expedited adverse event (EAE) 
reporting as indicated in Section 7.3.  
 
Site investigators are also responsible for prompt reporting of any unanticipated problems 
involving risks to participants or others to all applicable IRBs and other applicable review bodies, 
per the procedures of each applicable review body.  
 
7.1.2 
Protocol Safety Review Team (PSRT) 
 
A Protocol Safety Review Team (PSRT) will routinely review clinical and laboratory safety data 
reports prepared by the SDMC. Designees for PSRT members (e.g., a colleague who serves in a 
similar role as the PSRT member) will be allowed in the event of their non-availability for a 
review. To meet minimum quorum for a safety data review, the PSRT must include (but is not 
limited to): 
• 
A Protocol Chair or Vice Chair 
• 
A Data Manager 
• 
DAIDS or NICHD Medical Officer 
• 
A Protocol Statistician 
 
The content, format, and frequency of safety monitoring will be agreed upon in advance by the 
PSRT. The PSRT will be blinded to group assignment. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 59 of 106 
28 April 2022 
The PSRT will convene via teleconference or other means routinely throughout the study to 
review data relevant to safety monitoring and discuss any safety concerns – approximately twice 
per month during the Acute Phase and once a month thereafter – as well as on an ad hoc (as 
needed) basis outside of regularly scheduled calls. The PSRT will also provide rapid consultation 
to site clinicians regarding toxicity management as needed. 
 
On behalf of the full Protocol Team, the PSRT will monitor participant safety through routine 
review of study data reports as described in Section 9.4.2.  
 
7.1.3 
Data and Safety Monitoring Board (DSMB) 
 
An independent DSMB will monitor participant safety through routine and as needed reviews of 
study data. Refer to Section 9.4.3 for more information on the composition and role of the DSMB 
in monitoring of this study. Two to three ad hoc subject matter experts (i.e., ad hoc DSMB Expert 
Members) with expertise in pediatric respiratory virus vaccine development who are not 
otherwise affiliated with the Protocol Team will be added to the DSMB for review of this 
protocol. These ad hoc DSMB Expert Members will also perform ad hoc reviews of LRIs 
occurring during the Acute Phase and other safety concerns identified by the PSRT in real time as 
outlined in Section 9.4.  
 
7.2 
Safety-Related Data Collection 
 
Note: This section describes eCRF data collection for pre-existing conditions, adverse events, 
and laboratory test results. As part of this description, reference is made to severity grading and 
criteria for EAE reporting; refer to Sections 7.3.3 and 7.3.2, respectively, for detailed 
information on these topics.  
 
The definition of the term adverse event provided in Version 2.0 of the Manual for Expedited 
Reporting of Adverse Events to DAIDS (DAIDS EAE Manual) will be used in this study. This 
definition will be applied to all participants, beginning at the time of randomization, regardless of 
subsequent administration of or exposure to study product. Solicited AEs are predefined AEs that 
can occur after randomization, may be expected to occur if the study product is insufficiently 
attenuated, and have protocol-specific criteria for reporting. Any untoward medical conditions 
(including abnormal laboratory test results, signs, symptoms, or diagnoses) identified prior to 
enrollment will be considered pre-existing conditions. Refer to Section 4.4 for more information 
on defining the effective point of enrollment in the study. 
 
Pre-existing conditions, adverse events, and laboratory test results will be entered into eCRFs as 
specified below. 
 
Pre-Existing Conditions  
 
All pre-existing conditions identified as present during the screening period (prior to 
randomization) will be entered into medical history log eCRFs.  
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 60 of 106 
28 April 2022 
Adverse Events 
 
Adverse events — inclusive of abnormal laboratory test results and clinical signs, symptoms, and 
diagnoses — will be entered into adverse events log eCRFs as outlined in Table 5. In addition, for 
any event assessed as serious as defined in Version 2.0 of the DAIDS EAE Manual due to the 
event resulting in hospitalization or prolongation of hospitalization, data regarding the 
hospitalization will be entered into eCRFs.  
 
For IMPAACT 2021, solicited AEs, whether identified by a parent/guardian or clinician, are only 
entered into eCRFs if they meet the definitions per Appendix III. Individual symptoms listed in 
the “events” column that fail to meet the criteria in the “definition” column in Appendix III are 
recorded in source documents but are not entered into the eCRFs. From randomization through 
Day 28, solicited AEs meeting the criteria for reporting will be entered into eCRFs, assigned a 
severity grade (see Section 7.3.3, Table 6, and Table 7), and assessed for relationship to study 
product (see Section 8.1). For this study, the solicited AEs are defined in Appendix III and 
include the following:  
 
1. Fever 
2. Upper respiratory illness (URI) 
a. Rhinorrhea 
b. Pharyngitis,  
c. Cough without LRI, or 
d. Hoarseness. 
3. Otitis Media 
4. Lower respiratory illness (LRI) 
a. Wheezing, 
b. Pneumonia, 
c. Laryngotracheobronchitis (croup), 
d. Rhonchi, or 
e. Rales. 
 
Solicited Adverse Events Elicited by History Unconfirmed by Clinical Assessment 
 
With the exception of fever, solicited AEs reported by parents/guardians are NOT entered into 
eCRFs if a clinical assessment done on the day of the event(s) does/did not confirm their 
presence. For example, if a parent/guardian reports rhinorrhea on the day of visit, and there is/was 
no rhinorrhea upon exam, then the participant is considered to not have rhinorrhea that day. 
 
If the parent/guardian report of a fever meets the “definition” column criteria in Appendix III on a 
day on which there was a clinical assessment, the fever will be entered into eCRFs regardless of 
whether the clinical assessment confirmed its presence. 
 
Events elicited by parent/guardian history for days on which there was no clinical exam will be: 
 
• 
Entered into the eCRFs as AEs if the parent/guardian description meets the “definition” 
column criteria in Appendix III. 
• 
Recorded only on the source document, and NOT entered into the eCRF, if the 
parent/guardian description fails to meet the “definition” column criteria in Appendix III. For 
example, both rhinorrhea and cough must each occur on 2 consecutive days to meet the 
definition required for reporting per Appendix III. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 61 of 106 
28 April 2022 
Laboratory Test Results  
 
In addition to the recording specified above, laboratory test results will be entered into the 
relevant laboratory eCRFs, regardless of whether the test was protocol-specified or ordered by the 
site investigator for clinical purposes. 
 
This study has several periods of AE surveillance that have different AE eCRF entry 
requirements. In addition, there may be a period when no AEs are entered into eCRFs if Day 56 is 
before the start of the RSV Season Surveillance Period (November 1st for most sites or—for sites 
with local RSV seasons that differ—as specified on a site-by-site basis in the MOP). The adverse 
events (solicited and unsolicited; and serious AEs) to be entered into eCRFs and the study 
timeframe and the calendar dates during which they are to be reported are defined in Table 5. 
 
Adverse events identified in this study will be entered into adverse event log eCRFs as described 
in Table 5. Expectations regarding the recording of concomitant medications are also detailed in 
this table. 
 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 62 of 106 
28 April 2022 
Table 5: AE eCRF Entry Requirements 
Study Phase at the time 
of event onset 
Calendar Date 
AEs to enter into eCRFs 
Concomitant Medications to 
enter into eCRFs 
From randomization 
through midnight of 28th 
day following study 
product administration 
(Acute Phase) 
ANY 
• All serious AEs 
• All solicited AEs that meet 
Appendix III criteria  
• All unsolicited AEs (Grades 1 to 
4), with the exception of the 
following conditions if not treated 
with prescription medication or 
OTC medications with antipyretic 
properties: diaper rashes, teething 
pain, and spitting up. See MOP 
for additional guidance. 
 
Note: serious AEs and LRIs must be 
reported via DAIDS Adverse 
Experience Reporting System 
(DAERS; see Section 7.3.4).  
Enter these medications into 
eCRFs regardless of 
whether the related event is 
entered into eCRFs: 
• All cough and cold 
remedies including 
decongestants, cough 
suppressants, 
expectorants 
• All nasal sprays (except 
saline spray) 
• All antihistamines 
• All antipyretics 
• All prescription 
medications 
 
For serious AEs and LRIs: 
• All concomitant 
medications administered 
to treat the entered event 
From 12:01 am on 29th 
day after study product 
administration to 
midnight of the 56th day 
following study product 
administration 
(Post-Acute Phase) 
ANY 
• All serious AEs 
 
Note: serious AEs must be reported 
via DAERS (see Section 7.3.4). 
• All concomitant 
medications administered 
to treat the entered event 
After Day 56 and until 
RSV Season 
Surveillance Period 
Up to October 
31st* in year 
of study 
product 
administration 
• SUSARs 
• All concomitant 
medications administered 
to treat the entered event 
RSV Season 
Surveillance Period 
November 
1st* to March 
31st following 
study product 
administration 
• Fever, LRI, URI, and/or otitis 
media that are medically attended 
• All serious AEs  
 
Note: these events do not need to 
meet the Appendix III criteria. 
Serious AEs and Grade ≥3 LRIs 
must be reported via DAERS (see 
Section 7.3.4). 
For serious AEs and LRIs 
(all grades): 
• All concomitant 
medications administered 
to treat the entered event 
 
Medications administered 
to treat entered medically 
attended illness should be 
documented in source 
notes. 
Post-RSV Season 
April 1st-April 
30th in the 
year after the 
study product 
administration 
• Grade ≥3 AEs or serious AEs that 
is deemed related to Post-RSV 
Season Study Visit procedures. 
• SUSARs 
 
• All concomitant 
medications administered 
to treat the entered event 

 
IMPAACT 2021, FINAL Version 3.0 
Page 63 of 106 
28 April 2022 
Study Phase at the time 
of event onset 
Calendar Date 
AEs to enter into eCRFs 
Concomitant Medications to 
enter into eCRFs 
Throughout study 
ANY 
• Updated data on unresolved AEs 
or serious AEs with onset date 
during the timeframe from study 
product administration (Day 0) to 
midnight on the 28th day after Day 
0 
• Updated data on unresolved 
serious AEs with onset date prior 
to midnight on the 56th day 
following Day 0 
• Updated data on unresolved 
serious AEs with onset date during 
RSV Surveillance Period or related 
to the Post-RSV Season Study 
Visit 
 
Note: unresolved events should be 
followed to resolution or until no 
further change is expected. 
• All concomitant 
medications administered 
to treat the entered event 
*These dates apply to most sites but may differ for those with local RSV seasons that differ (see MOP). 
 
7.3 
Expedited Adverse Event (EAE) Reporting 
 
7.3.1 
EAE Reporting to DAIDS 
 
Requirements, definitions, and methods for expedited reporting of adverse events (AEs) are 
outlined in Version 2.0 of the DAIDS EAE Manual, which is available on the DAIDS RSC 
website at https://rsc.niaid.nih.gov/clinical-research-sites/manual-expedited-reporting-adverse-
events-daids. 
 
The DAIDS Adverse Experience Reporting System (DAERS), an internet-based reporting 
system, must be used for expedited AE reporting to DAIDS. In the event of system outages or 
technical difficulties, expedited AEs may be submitted via the DAIDS EAE Form. This form is 
available on the DAIDS RSC website at: https://rsc.niaid.nih.gov/clinical-research-sites/paper-
eae-reporting. 
 
For questions about DAERS, please contact NIAID CRMS at CRMSsupport@niaid.nih.gov. 
Please note that site queries may also be sent from within the DAERS application itself. 
 
For questions about expedited reporting, please contact the DAIDS RSC Safety Office at 
DAIDSRSCSafetyOffice@tech-res.com. 
 
7.3.2 
EAE Reporting Requirements for this Study 
 
• 
Both the Serious Adverse Event and SUSAR Reporting Categories, as defined in Version 
2.0 of the DAIDS EAE Manual, will be used by this study. Reporting periods for both 
categories are defined in Table 8. 
• 
The study agents for which expedited reporting is required are recombinant live-
attenuated respiratory syncytial virus vaccines RSV ΔNS2/Δ1313/I1314L, RSV 
6120/ΔNS2/1030s, and RSV 276 (protocol V1.0 only) and placebo. 

 
IMPAACT 2021, FINAL Version 3.0 
Page 64 of 106 
28 April 2022 
• 
In addition to the Serious Adverse Event Reporting Category identified above, other AEs 
that must be reported in an expedited manner are LRIs occurring during the periods 
specified in Table 8. 
 
7.3.3 
Grading Severity of Events (applies to EAEs and all other adverse events) 
 
All solicited AEs and fever will be graded following the protocol-defined grading system outlined 
in Table 6 and Table 7. Other AEs (i.e., excluding solicited AEs and fever) will be assessed for 
severity by the site investigator using the Division of AIDS Table for Grading the Severity of 
Adult and Pediatric Adverse Events (DAIDS AE Grading Table): Corrected Version 2.1, dated 
July 2017. In the event that this table is updated following protocol implementation, events will 
continue to be evaluated per this version of the DAIDS AE Grading Table. The DAIDS AE 
Grading Table is available on the RSC website at https://rsc.niaid.nih.gov/clinical-research-sites/ 
daids-adverse-event-grading-tables. 
 
Solicited AE Grading 
 
Table 6: Grading Table for Solicited AEs 
 
Severity 
Defined 
Grade (1) Mild 
No medical intervention required; may include use of over-the-counter 
medications managed by the caregiver for treatment of symptoms; does 
not interfere with usual activities (e.g., eating, sleeping, playing) 
Grade (2) Moderate 
Moderate symptoms, i.e., symptoms interfering to some degree with 
usual activities. In most cases, symptoms severe enough to necessitate a 
medical care visit would likely meet this criterion; however, if medical 
care is sought and symptoms are assessed as only mild, the event may 
remain Grade 1. If prescription medication is used or recommended for 
symptoms, the event automatically moves to at least Grade 2.   
Grade (3) Severe 
Prolonged medical intervention and/or hospitalization required 
Grade (4) Life 
threatening 
Illness requiring hospitalization with intensive care  
Grade (5) Death 
Event resulting in fatal outcome to the participant 
 
Fever Grading: Temperature Measurement 
Table 7: Fever Grading* 
 
 
 
 
 
Severity 
Defined 
Grade (0)** 
≥100.0ºF but <100.4ºF (≥37.8ºC but <38ºC) 
Grade (1) 
≥100.4ºF but <101.5ºF (≥38ºC but <38.6ºC) 
Grade (2) 
≥101.5ºF but <102.5ºF (≥38.6ºC but <39.2ºC) 
Grade (3) 
≥102.5ºF but <104.9ºF (≥39.2ºC but <40.5ºC) 
Grade (4) 
≥104.9ºF (≥40.5ºC)  
*Applies to any modality of temperature measurement 
**Grade 0 is to be used only when temporal temperature is ≥100.0 but <100.4 and no rectal 
temperature is measured.   
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 65 of 106 
28 April 2022 
The expedited AE reporting period for this study is defined in Section 7.3.4. 
 
7.3.4 
EAE Reporting Period 
 
Table 8 details the events that must be reported in an expedited fashion via DAERS during 
specific periods of the study. 
 
 
Table 8: EAE Reporting 
 
Study Phase at the time of 
event onset 
Calendar Date 
Events to Report via 
DAERS 
From randomization through midnight 
of 28th day following study product 
administration 
(Acute Phase) 
ANY 
• Serious AEs  
• LRIs 
From 12:01 am on 29th day after study 
product administration to midnight of 
the 56th day following study product 
administration 
(Post-Acute Phase) 
ANY 
• Serious AEs 
 
After Day 56 and until RSV Season 
Surveillance Period 
 
Up to October 31st* in year of 
study product administration 
• Follow-up related to 
Serious AEs/LRIs 
already reported 
• SUSARs 
RSV Season Surveillance Period 
November 1st* to March 31st 
following study product 
administration 
 
• Serious AEs 
• Grade ≥3 LRIs 
 
Post-RSV Season 
April 1st to April 30th in the year 
after the study product 
administration 
• Serious AEs related 
to Post-RSV Season 
Study Visit 
procedures  
• SUSARs 
 
*These dates apply to most sites but may differ for those with local RSV seasons that differ (see MOP). 
 
After the protocol-defined EAE reporting period, unless otherwise noted, only serious and 
unexpected suspected adverse reactions (SUSARs) as defined in Version 2.0 of the DAIDS EAE 
Manual will be reported to DAIDS if the study staff become aware of the events on a passive 
basis (from publicly available information).  
 
8 
PARTICIPANT MANAGEMENT 
 
8.1 
Management of Adverse Events 
 
All adverse events identified in this study will be source documented in participant research 
records, consistent with the requirements referenced in Section 10. Among other details, source 
documentation will include the severity of each event (graded as described in Section 7.3.3) and 
its relationship to study product, assessed by the site clinician (see below).   
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 66 of 106 
28 April 2022 
Relationship categories for Adverse Events are as follows: 
 
Related 
There is a reasonable possibility that the adverse event may be related to 
the study drug. 
 
Not related 
There is not a reasonable possibility that the adverse event may be 
related to the study drug.  
 
Further standardized guidance on determining whether there is a reasonable possibility of a 
relationship is available in the DAIDS EAE Manual, referenced in Section 7.3.1. 
 
Study staff who administer study product and assess AEs will be blinded. If the need arises to 
unblind a specific participant’s assignment to guide management of a serious illness or medical 
emergency or if knowing the participant’s treatment assignment would otherwise affect decisions 
regarding the participant’s immediate medical management as determined by the site Investigator 
of Record (IoR) or treating clinician, the procedures for emergency unblinding specified in the 
IMPAACT Network Manual of Procedures (MOP) must be followed. In the event that unblinding 
is required, only that specific participant’s assignment will be unblinded. 
 
9 
STATISTICAL CONSIDERATIONS 
 
9.1 
General Design Issues 
 
The goal of this Phase I/II blinded, randomized, placebo-controlled study is to assess the safety 
and immunogenicity of three RSV vaccine candidates (RSV ΔNS2/Δ1313/I1314L, RSV 
6120/ΔNS2/1030s and RSV 276) in RSV-seronegative children, and to determine whether any of 
the vaccines are good candidates to move forward into larger safety and efficacy studies. Note 
that adjustments to the candidate vaccines included in the study may be made as outlined in 
Section 1.4. 
 
Since clinical testing of RSV vaccines is only possible outside the time during which wt RSV 
circulates in the community, and since vaccine studies have long preparation and follow-up 
periods, it is essential that vaccine development planning be as efficient and timely as possible. 
To move forward, the vaccines should: 
 
1. be safe, and 
2. result in at least 70% of vaccine recipients having a ≥4-fold rise in serum RSV-neutralizing 
antibody titers from pre-study product administration to the Day 56 Visit after study product 
administration. 
 
At this stage in the development of a vaccine for RSV, it is difficult to predict the behavior of 
each candidate vaccine with respect to replication, tolerability, and vaccine-induced immunity, 
and difficult to set precise benchmarks for each of these individual characteristics to determine 
the ‘best’ candidate vaccine. The goal of this study is to obtain more precise estimates of vaccine-
induced immune responses (≥4-fold rise in serum RSV-neutralizing antibody titers from pre-
study product administration to the Day 56 Visit) and gain additional knowledge about safety and 
replication, to help inform whether any of the candidate vaccines should go forward into larger 
studies. The proposed sample size is not sufficient to definitively assess safety or superiority in 
immunogenicity of one vaccine candidate over the others unless one has a very poor safety 
profile or immunogenicity.   

 
IMPAACT 2021, FINAL Version 3.0 
Page 67 of 106 
28 April 2022 
 
As with protocol V2.0, under protocol V3.0, participants will be randomized equally (1:1:1) to 
receive one of the two candidate vaccines or placebo (40 per arm). Eligible children living in the 
same household (including twins, siblings, or other non-related children living in the same 
household) will be allowed to enroll and will be randomized per Section 9.3.1. Participants will 
be enrolled outside the time during which wt RSV circulates in the community and followed 
through the RSV season that starts in the calendar year in which they receive study product with a 
final study visit in April of the following calendar year.  
 
The study will be reviewed by the NIAID Intramural Data and Safety Monitoring Board 
(DSMB), which will include ad hoc DSMB Expert members who are experts in pediatric 
respiratory vaccine development. The DSMB will review safety twice per year, Day 56 immune 
response rates at the conclusion of Day 56 follow-up during each calendar year, and if there are 
safety concerns between scheduled reviews. If targeted enrollment is achieved in one season, data 
collection for the primary objectives and two secondary objectives will be complete once all 
participants have completed their Day 56 Visit. Once immunologic samples have been assayed, 
safety and immunogenicity data will be analyzed and an unblinded primary analysis report 
distributed to the DSMB and a subset of the Protocol Team not involved in ongoing safety 
monitoring. This report will contain key information needed to plan vaccine studies for the 
subsequent year, and release of this information to selected members of the Protocol Team will 
not compromise safety monitoring through the remainder of the surveillance season. The study 
was not fully accrued in the first enrollment season (2019), and the DSMB recommended that the 
study continue when feasible in the context of the COVID-19 pandemic. Due to COVID-19, the 
study did not reopen during the second enrollment season (2020). During the winter of 2021, 
newly available unblinded data from IMPAACT 2018/CIR 321 and CIR 322 were reviewed, and 
it was determined that the RSV 276 vaccine arm of IMPAACT 2021 would be closed to further 
enrollment under protocol V2.0, and this arm remains closed under protocol V3.0.  
 
No sites were able to resume enrollment during the third enrollment season (2021); thus, 
enrollment is anticipated to resume for a fourth enrollment season (e.g., 2022). If a fifth 
enrollment season (e.g., 2023) is considered, the DSMB will review results from the fourth 
enrollment season (e.g., 2022) to confirm if all candidate vaccines should remain in the study. If 
enrollment is closed to an arm, the remaining arms would continue to enroll to the 40-per-arm 
goal.   
 
9.2 
Objectives and Outcome Measures 
 
The primary and secondary outcome measures listed below will be addressed in the study’s 
primary Statistical Analysis Plan, which will define the content of the Primary Analysis Report. 
This report will form the basis for the primary study manuscript and results reporting to 
ClinicalTrials.gov.  
 
9.2.1 
Primary Outcome Measures 
 
Objective 1: Safety: To estimate and compare (each vaccine group to placebo) the frequency and 
severity of adverse events (AEs) following study product administration (Day 0) through Day 56  
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 68 of 106 
28 April 2022 
Outcome measures: 
 
1. Grade 1 or higher solicited AEs as defined in Appendix III from Day 0 through Day 28 
2. Grade 2 or higher LRIs as defined in Appendix III from Day 0 through Day 28 
3. Serious AEs from Day 0 through Day 56 
 
Objective 2: Immunogenicity: To estimate and compare (between the vaccine groups and to the 
benchmark of 70%) the percentage of vaccinees having a ≥4-fold rise in serum RSV-neutralizing 
antibodies at the Day 56 Visit 
Outcome measure: 
 
4. ≥4-fold rise in serum RSV-neutralizing antibody titer from pre-study product administration 
(screening) to the Day 56 Visit 
 
Titer is quantified even if <1:40; therefore, a ≥4-fold rise can be determined even for lower titers. 
 
9.2.2 
Secondary Outcome Measures 
 
Objective 1: Immunogenicity: To estimate and compare (between the vaccine groups) the 
percentage of vaccinees with a ≥4-fold rise in serum IgG antibody to RSV F protein (RSV F IgG) 
at the Day 56 Visit 
 
Outcome measure: 
 
1. ≥4-fold rise in serum RSV F IgG from pre-study product administration (screening) to the 
Day 56 Visit 
 
Objective 2: Immunogenicity: To estimate and compare (between the vaccine groups) the titers of 
serum RSV F IgG and serum RSV-neutralizing antibodies at the Day 56 Visit 
 
Outcome measures: 
 
2. Titer of serum RSV F IgG at the Day 56 Visit 
3. Titer of serum RSV-neutralizing antibodies at the Day 56 Visit 
 
Objective 3: Safety: To describe and compare the frequency and severity of RSV-associated 
medically attended acute respiratory illness (RSV-MAARI) and RSV-associated medically 
attended acute lower respiratory illness (RSV-MAALRI) in the placebo and vaccine arms during 
RSV season  
 
Outcome measures: 
 
4. RSV-MAARI and maximum grade (if more than one illness within a participant) 
5. RSV-MAALRI and maximum grade (if more than one illness within a participant) 
 
9.2.3 
Exploratory Outcome Measures 
 
Objective 1: To evaluate the association of vaccine virus shedding with adverse events: To assess 
the incidence and magnitude of vaccine virus shedding in samples collected at Illness Visits 
associated with solicited AEs on Study Days 0 through 28 and with serious AEs from Study Day 0 
through Day 56 

 
IMPAACT 2021, FINAL Version 3.0 
Page 69 of 106 
28 April 2022 
 
Outcome measures: 
 
For solicited AEs between Days 0 and 28 (more than one per participant possible). Detection and 
magnitude of vaccine virus shedding detected in Illness Visit specimens as determined by:  
 
1. RT-PCR 
2. culture (when possible)  
 
For serious AEs between Days 0 and 56 (more than one per participant possible). Detection and 
magnitude of vaccine virus shedding detected in Illness Visit specimens as determined by: 
 
3. RT-PCR 
4. culture (when possible)  
 
Objective 2: Immunogenicity – timing of maximum response: To estimate and compare serum 
RSV F IgG and serum RSV-neutralizing antibody responses at the Day 28 and 56 Visits in each 
vaccine group   
 
Outcome measures: 
 
5. Titer of serum RSV F IgG at the Day 28 and 56 Visits 
6. Titer of serum RSV-neutralizing antibodies at the Day 28 and 56 Visits 
 
Objective 3: Immunogenicity – magnitude of anamnestic response: To estimate and compare 
(each vaccine group to placebo and between the vaccine groups) the titers of serum RSV F IgG 
and serum RSV-neutralizing antibodies in participants infected with wt RSV during the RSV 
season  
 
Outcome measures: 
 
In subset of children who had RSV infection documented during the RSV season (via viral testing 
confirming presence of RSV or a further ≥2.5-fold rise in serum RSV-neutralizing antibody titers 
from the Day 56 Visit to the Post-RSV Season Visit): 
 
7. Titer of serum RSV F IgG at the Day 56 and Post-RSV Season Visits  
8. Titer of serum RSV-neutralizing antibodies at the Day 56 and Post-RSV Season Visits 
 
Objective 4: Immunogenicity – durability of vaccine-induced RSV antibodies: to estimate and 
compare (between the vaccine groups), the magnitude of RSV serum antibody titers in samples 
collected at the Day 56 and Post-RSV Season Visits among vaccine recipients who do not have 
evidence of RSV infection during RSV season  
 
Outcome measures: 
 
In subset of children who achieve ≥4-fold rises in serum RSV-neutralizing antibody titers 
between pre-study product administration and the Day 56 Visit and with no evidence of RSV 
infection after Day 56 (no RSV infection identified by viral testing done at the site or centrally 
and <2.5-fold rise in serum RSV-neutralizing antibody titers from the Day 56 Visit to the Post-
RSV Season Visit): 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 70 of 106 
28 April 2022 
9. Titer of serum RSV F IgG at Day 56 and Post-RSV Season Visits  
10. Titer of serum RSV-neutralizing antibodies at Day 56 and Post-RSV Season Visits 
 
9.3 
Randomization and Sample Size 
 
 
 
9.3.1 
Randomization 
 
As with protocol V2.0, under protocol V3.0, RSV-seronegative children will be randomized 
equally (1:1:1) to receive one of two candidate vaccines (RSV ΔNS2/Δ1313/I1314L (106 PFU) or 
RSV 6120/ΔNS2/1030s (105 PFU)) or placebo. Under protocol V1.0, prior to the closure of the 
RSV 276 (105 PFU) arm, participants were previously randomized equally to one of three 
candidate vaccines (RSV ΔNS2/Δ1313/I1314L (106 PFU), RSV 6120/ΔNS2/1030s (105 PFU), or 
RSV 276 (105 PFU)) or placebo.   
 
Randomization will use permuted blocks. Eligible children from the same household are allowed 
to enroll: they must either be enrolled on the same date and to the same study arm to reduce 
potential cross-contamination that could occur if children living together were to receive different 
study products, or additional children in the household can be screened, enrolled, and randomized 
independently after other children in the household complete the Day 56 Visit.  
 
9.3.2 
Sample Size 
 
A target sample size of approximately 40 per arm was chosen to gather more data on safety and to 
yield sufficiently precise confidence intervals around Day 56 immunogenicity to help inform 
which candidate vaccines should go forward into larger studies. The total expected sample size is 
approximately 130, including approximately 40 each in the placebo and two candidate vaccine 
arms open under protocol V2.0 and V3.0 (RSV ΔNS2/Δ1313/I1314L and RSV 
6120/ΔNS2/1030s), as well as all participants previously randomized to receive RSV 276 (105 
PFU) under protocol V1.0 prior to closure of this arm. 
 
To fully assess safety, much larger sample sizes will be required, and additional studies will need 
to be conducted on the candidate vaccines identified as promising in this trial. Declaring 
superiority in immunogenicity of one vaccine candidate over another will only be possible if one 
candidate has very poor immunogenicity.   
 
9.3.2.1 Immunogenicity 
 
If multiple children living in the same household are enrolled on the same date, one will be 
randomly chosen for the primary immunogenicity analysis. Assuming enrollment of 40 
participants per arm and an exclusion rate of 5% (losses-to-follow-up, non-evaluability, or non-
selected siblings), approximately 38 participants per arm will be evaluable for the primary initial 
response to vaccine immunogenicity outcome measure. The goal of the study is to estimate the 
response rates in each candidate vaccine arm with sufficient precision to make a decision about 
whether that vaccine should move forward into larger studies. Table 9 shows exact 95% 
confidence intervals (CIs) around various observed response rates with a sample size of 38. For 
example, if the response rate is estimated to be 79%, the 95% CI would be (63%, 91%), and the 
study can be reasonably sure that the actual response rate is greater than 63%.   
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 71 of 106 
28 April 2022 
Table 9: Exact 95% confidence intervals for various observed vaccine 
response rates with a sample size of 38 
 
Observed ≥4-fold rise in RSV antibody 
N (%) 
95% CI 
20 (53%) 
(36%, 69%) 
24 (63%) 
(46%, 78%) 
28 (74%) 
(57%, 87%) 
30 (79%) 
(63%, 91%) 
32 (84%) 
(69%, 94%) 
34 (90%) 
(75%, 97%) 
 
For a product to be considered a good candidate, a response rate of at least 70% is desirable. With 
38 participants, the study will have greater than 80% power to reject the null hypothesis if the true 
response rate is at least 90% (two-sided hypothesis test with Type I error of 5%).  
 
Response rates among the vaccine arms will be compared with two-sided tests of the null 
hypothesis that the response rates are the same. With 38 participants per arm, there would be at 
least 80% power to detect differences of more than 33% if the true response rate in the inferior 
arm is less than 50% (Type I error of 5%).   
 
9.3.2.2 Safety 
 
Safety summaries will include all enrolled participants, including all children from within the 
same household who enrolled on the same date and each counted separately. Safety outcome 
measures include types of events that will be frequent but less serious (e.g., Grade 1 solicited 
AEs) and some that will be rare but serious (Grade 3 or higher AEs, serious AEs and LRIs), 
which if they occurred in the vaccine arms, would be of concern.   
 
Safety of each vaccine must be interpreted relative to the rates of comparable events over a 
comparable time period in the placebo arm. Rates will be compared using two-sided 95% CIs 
around the differences in rates of AEs between the vaccine arms (PV) and the placebo arm (PC). 
Table 10 shows exact CIs for differences in various observed rates of AEs between the vaccine 
and placebo groups with 40 participants per arm. If the observed AE rate in the placebo arm is 
50%, differences in rates of more than 20% between arms would result in CIs not covering the 
value 0.  
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 72 of 106 
28 April 2022 
Table 10: Differences (exact 95% CIs) in observed rates of AEs between 
vaccine and placebo arms  
 
Observed N (%) of AEs  
Observed difference  
(pv – pc) 
95% CI for   
(pv – pc) 
 
Placebo (pc) 
Vaccine (pv) 
 
N=40 
20 (50%) 
24 (60%) 
10% 
(-12%, 32%) 
 
28 (70%) 
20% 
 (-1%, 41%) 
 
32 (80%) 
30% 
(10%, 50%) 
14 (35%)  
18 (45%) 
10% 
(-11%, 31%) 
 
22 (55%) 
20% 
(-1%, 41%) 
 
26 (65%) 
30% 
(9%, 51%) 
10 (25%) 
14 (35%) 
10% 
(-10%, 30%) 
 
18 (45%) 
20% 
(0%, 40%) 
 
22 (55%) 
30% 
(10%, 50%) 
4 (10%) 
8 (20%) 
10% 
(-5%, 25%) 
 
12 (30%) 
20% 
(3%, 37%) 
 
16 (40%) 
30% 
(12%, 48%) 
2 (5%) 
6 (15%) 
10% 
(-3%, 23%) 
 
10 (25%) 
20% 
(5%, 35%) 
 
Potentially serious LRIs will be monitored closely and are likely to occur. Previous studies 
indicate that about 2.8% of participants will develop an LRI. With this underlying rate in 160 
children, there would be an 83% chance of seeing >2 LRIs. With 40 participants, if the 
underlying LRI probability is 0.01, the chance of seeing >2 LRIs is <1%. If the underlying 
probability of an LRI is 5 times higher (0.05), the chance of seeing >2 LRIs is 32%. If the 
underlying probability of an LRI in the placebo arm is 0.01, and in each vaccine arm it is 0.05, 
the average probability across arms would be 0.04, and with 160 participants, the chance of 
seeing >2 LRIs would be about 96%.   
 
Table 11 shows two-sided exact 95% CIs for a range of observed numbers of AEs. For example, 
if no AE of a given type is observed among 40 participants, the team is 95% confident that the 
underlying probability of that AE in that study arm is between 0% and 9%.   
 
Table 11: Exact 95% confidence intervals for range of numbers of observed 
events among 40 participants 
 
Observed N (%) of AEs  
95% CI  
0 (0%) 
(0%, 9%) 
2 (5%) 
(1%, 17%) 
3 (8%) 
(2%, 20%) 
5 (13%) 
(4%, 27%) 
7 (18%) 
(7%, 33%) 
10 (25%) 
(13%, 41%) 
15 (38%) 
(23%, 54%) 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 73 of 106 
28 April 2022 
9.4 
Monitoring 
 
Full details of monitoring reports will be described in a separate Study Progress Data and Safety 
Monitoring Plan (SPDSMP). The study will be monitored by the groups described in Table 12. 
 
Table 12: Groups responsible for monitoring  
Group 
Membership 
Responsibility 
Approximate 
frequency 
Blinding status 
IMPAACT 
Leadership 
IMPAACT 
Management 
Oversight Group 
(MOG) 
Accrual according to 
standard operating 
procedures 
Monthly 
Blinded 
Protocol Team  
Accrual and retention 
Monthly 
Blinded  
Protocol 
Safety Review 
Team 
(PSRT)* 
Protocol Chair(s), 
Vice Chair(s), Medical 
Officer(s), LID 
investigator(s), 
Protocol 
Statistician(s), 
Protocol and Lab Data 
Manager(s), CRM(s) 
Safety 
Twice monthly while 
participants are within 
28 days post-study 
product administration 
and at least monthly 
thereafter 
Blinded  
Data and 
Safety 
Monitoring 
Board 
(DSMB) 
Standing NIAID 
Intramural DSMB 
with 2-3 ad hoc 
DSMB Expert 
Members who are 
experts in pediatric 
respiratory virus 
vaccine development 
 
Safety; 
data monitoring, 
recommendations on 
continuation, study 
modifications, 
suspension, or 
termination 
 
2-3 ad hoc DSMB 
Expert Members who 
are experts in pediatric 
respiratory virus 
vaccine development 
will adjudicate LRIs 
during Days 0 – 28 and 
AEs/serious AEs at 
request of PSRT in real 
time. 
Twice a year 
(September/February);  
 
Expert Member ad hoc 
review of LRIs during 
Days 0 – 28 and 
AEs/serious AEs at 
request of PSRT 
 
Full DSMB ad hoc 
review if requested by 
ad hoc DSMB Expert 
Members 
Masked for twice 
yearly reviews 
with option to 
unblind if 
necessary 
 
Unblinded for ad 
hoc reviews 
DAIDS 
Medical 
Officer 
DAIDS 
Pharmacovigilance, 
medical review of 
EAEs, safety reports to 
the FDA as needed 
As EAEs are reported 
by sites through 
DAERS 
Blinded 
*See Section 7.1.2 for a listing of PSRT members required to meet minimum quorum for a safety data review. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 74 of 106 
28 April 2022 
9.4.1 
Monitoring of Accrual and Retention by the Protocol Team 
 
The Protocol Team is responsible for continuous monitoring of study progress, including timely 
achievement of key milestones, and quality of study conduct.  The team will closely monitor 
participant accrual and retention based on reports generated at least monthly by the Statistical and 
Data Management Center (SDMC). The team has developed an accrual plan that includes site-
specific and total enrollment projections over the course of the accrual period, and actual accrual 
will be monitored relative to these projections. The team will monitor the timing of site-specific 
study activation, which will determine when each site will begin accruing participants, and actual 
accrual following activation. For any site that is delayed in completing the study activation 
process, or that falls short of its accrual projections, the team will communicate with the site to 
identify the barriers the site has encountered and the operational strategies and action plans to 
address these. If relatively few of the eligible sites have been activated after the study has been 
open to accrual, the team will periodically re-assess the feasibility of the study and the reasons 
why sites have not been activated and may make adjustments as needed.   
 
The Protocol Team will similarly review participant retention and other key indicators of the 
quality of study conduct (e.g., data quality, and data and specimen completeness) based on reports 
generated by the SDMC and will follow up with study sites as needed to ensure high quality 
study conduct throughout the period of study implementation.  
 
9.4.2 
Monitoring of Safety by the Protocol Safety Review Team (PSRT) and ad hoc DSMB Expert 
Members 
 
Two to three additional ad hoc DSMB Expert Members with expertise in pediatric respiratory 
virus vaccine development will be added to the DSMB for review of this protocol. These ad hoc 
DSMB Expert Members will perform real-time ad hoc reviews of individual (unblinded) cases of 
LRIs and serious adverse events not attributed to an etiology or cause unrelated to the study 
product to assess whether detection of vaccine virus is associated with the illness.  
 
The SDMC will generate reports of adverse events pooled across arms (with the vaccine and 
placebo arms presented together). Safety reports will be reviewed by the Protocol Safety Review 
Team (PSRT), which includes the Protocol Chair(s) and/or Vice Chair(s), Medical Officer(s), 
LID investigator(s), Protocol Statistician(s), Protocol and Lab Data Manager(s), and CRM(s). The 
PSRT will monitor participant safety via conference call or other meeting approximately twice a 
month during the Acute Phase (i.e., until the last participant enrolled in that season has been 
followed for 28 days post-study product administration) and monthly until all participants have 
reached Day 56. On these calls, the DAIDS Medical Officer will also review any EAEs reported 
to the DAIDS Safety Office not yet entered in the study database.   
 
Ad hoc DSMB Expert Member reviews will be requested by the PSRT if: 
 
• 
any LRIs, intensive care unit (ICU) admissions, or deaths occur within 28 days of study 
product administration or 
• 
>1 serious AE occurs within 56 days of study product administration or 
• 
>1 Grade 4 fever occurs within 14 days of study product administration or  
• 
>1 Grade ≥3 solicited AE (excluding rhinorrhea and fever) occurs within 28 days of study 
product administration.  
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 75 of 106 
28 April 2022 
In the event of a participant’s ICU admission or death within 28 days of study product 
administration that is considered related to study product administration, accrual and study 
product administration will stop pending review. In all other cases, accrual and study product 
administration will continue while ad hoc DSMB Expert Member review is in progress. The 
review will be convened per DSMB guidelines. The site will send respiratory viral samples to the 
JHU CIR laboratory to determine shedding of RSV or adventitious viral agents, and the lab will 
send their results for ad hoc review directly to the ad hoc DSMB Expert Members (results will 
ultimately be included in the study database). Independent SDMC personnel other than the 
Protocol Statistician will send the ad hoc DSMB Expert Members the participant’s treatment 
assignment. The ad hoc DSMB Expert Members will review the relevant safety information and 
available data, including presence of vaccine virus shedding, whether other adventitious agents 
are present, and whether the participant received placebo or one of the candidate vaccines. The ad 
hoc DSMB Expert Members will review whether the AE, serious AE, or LRI can be attributed to 
an etiology, a cause, or a diagnosis unrelated to the study vaccine, and if it is associated with 
shedding of vaccine virus at the time of the event (even if another pathogen is identified). The ad 
hoc DSMB Expert Members will report their assessment to the DSMB. Based on (1) the severity 
of the event, (2) whether the participant received a candidate vaccine and (3) whether RSV and/or 
other agents are present in the nasal swab, the ad hoc DSMB Expert Members may recommend to 
the DSMB that enrollment be continued or paused pending full DSMB review.    
 
If the DSMB decides the study can continue unchanged, they will communicate their findings to 
the Protocol Team. Alternatively, the DSMB may recommend modifications to the study design.    
 
9.4.3 
Monitoring by the NIAID Intramural Data and Safety Monitoring Board 
 
The NIAID Intramural DSMB is constituted to review the safety data of Intramural NIAID 
clinical studies that require DSMB oversight. The NIAID Intramural DSMB includes independent 
experts in infectious diseases, biostatistics, and clinical research who do not have direct 
involvement in the conduct of the study and have no significant conflicts of interests as defined 
by NIAID policy. Standing DSMB membership is outlined in the NIAID Policy on the Intramural 
Research Program Data and Safety Monitoring Board, and for this study, the DSMB will also 
include ad hoc DSMB Expert Members who are experts in pediatric respiratory vaccine 
development (Section 9.4.2).  
 
The DSMB will review the protocol and Study Progress, Data, and Safety Monitoring Plan 
(SPDSMP) prior to the study opening to enrollment and then at least twice a year 
(August/September and February) or on a schedule specified by the DSMB. All reviews will 
focus on accrual, data completeness, adherence to the protocol, and safety. If full enrollment is 
not achieved in the first season, once Day 56 immunogenicity results are available (February of 
the subsequent calendar year), the DSMB will review the immunogenicity data. Once enrollment 
and follow-up through Day 56 is complete, a primary analysis report addressing the study’s 
primary and first two secondary objectives will be finalized. This report will be sent to the DSMB 
and a subset of the Protocol Team not reviewing ongoing safety during the surveillance period. 
This report will be used to plan vaccine studies for the subsequent calendar year. Once follow-up 
is complete through the end of the surveillance period, the DSMB will be sent a copy of the 
second analysis report.   
 
During enrollment, two reports will be submitted to the DSMB Executive Secretary for 
distribution to the DSMB members: one that pools data across arms and a second broken down by 
masked treatment arm. Codes identifying the arms will be provided separately. The goals of the 
reviews are to drop any vaccine arms that have clearly inferior immunogenicity or safety 

 
IMPAACT 2021, FINAL Version 3.0 
Page 76 of 106 
28 April 2022 
concerns. Since this is a Phase I/II study, no adjustments are made to account for the impact of 
multiple looks on Type I error rates.   
 
The DSMB might consider halting enrollment to a vaccine arm: 
 
1. for clear differences in immunogenicity: if there a statistically significant difference in the 
percentage with immune response (>4-fold rise in serum RSV-neutralizing antibodies) to the 
candidate vaccines such that one or two products can be identified to be immunologically 
superior to the remaining product or products, with the absence of a safety signal among the 
higher performing product(s) 
2. for inadequate immunogenicity: the upper limit of a 95% CI around the response rate (≥4-
fold rise in RSV-neutralizing antibody titer) for a vaccine arm is less than 70%.  [With a 
sample size of 10 (15, 20, 25, 30, 38), this would occur if the observed response rate was 
<30% (<40%, <45%, <48%, <50%, <53%)] 
3. for safety concerns (also considering vaccine virus shedding and adventitious data): 
a. if >2 participants receiving the specific product experience LRIs of ≥Grade 2 in the 
28 days following study product administration for which vaccine virus is isolated 
without other potential explanation 
b. if there are ≥2 participants with vaccine-associated Grade 4 events of similar type 
(otitis media or pharyngitis within 28 days of study product administration) with 
presence of vaccine virus without other potential explanation. 
                 
After each ad hoc or interim review, the DSMB Executive Secretary will promptly provide the 
Protocol Chair with the DSMB’s recommendations, and the official DSMB Recommendations 
will be provided in a timely fashion through the office of the NIAID Clinical Director. The 
Protocol Team will circulate written DSMB recommendations to the sites upon receipt for 
submission to applicable IRBs.  
 
9.5 
Analyses 
 
A detailed description of analyses will be described in a separate Statistical Analysis Plan (SAP). 
Since this is a Phase I/II study, statistical comparisons will not be adjusted for multiple 
comparisons or interim looks by the DSMB. Exact confidence intervals will be calculated using 
the method of Clopper-Pearson.  
 
9.5.1 
Primary Safety Outcome Measures  
 
All children who receive study product will be included in safety analyses. Safety outcome 
measures will be included if they occur after study product administration.   
 
The number and proportion (two-sided 95% CI) of participants who experience each primary 
safety outcome measure will be summarized by study arm. The difference in proportions (95% 
CI) between each vaccine group and the placebo group will be calculated. Supportive analyses 
that stratify by time of enrollment will be performed to account for potential ascertainment 
differences related to COVID-19. In addition, for each primary safety outcome measure, the 
worst grade experienced by each participant will be summarized, including all graded events. 
Rare events (LRIs and serious AEs) will be summarized with details including site-assessed 
relationship with the study product.  
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 77 of 106 
28 April 2022 
9.5.2 
Primary Immunogenicity Outcome Measures 
 
This will be a per-protocol analysis including children who receive the as-randomized study 
vaccine and have serum RSV-neutralizing antibody titer results at pre-study product 
administration (screening) and the Day 56 Visit. In the event that twins, siblings, or other non-
related children living in the same household are enrolled on the same date, one will be randomly 
selected to be included in the primary analysis.   
 
Children will be classified as a responder to the vaccine if they achieve a ≥4-fold increase in 
serum RSV-neutralizing antibody titers from pre-study product administration to the Day 56 
Visit. Proportions (95% CIs) of responders will be summarized by arm. Pair-wise differences in 
response rates with 95% CIs between the vaccine arms (and differences between vaccine and 
placebo arms) will be summarized. Sensitivity analyses to ensure that results support the same 
overall conclusion will be performed in which the selected child is replaced by other siblings or 
other children from the same household who enrolled on the same date. Secondary analyses will 
include (i) classifying participants missing their Day 56 antibody titer as failures, (ii) in the intent-
to-treat population including all participants as-randomized regardless of vaccine receipt, and (iii) 
using an outcome measure defined as a ≥4-fold increase in serum RSV-neutralizing antibody 
titers from pre-study product administration to the Day 56 Visit and no wild-type RSV infection 
detected before Day 56. If enrollment takes place over more than one season, response rates will 
be summarized by calendar year of enrollment.   
 
9.5.3 
Secondary Outcome Measures  
 
Children will be classified as responders to the vaccine if they achieve a ≥4-fold increase in 
serum RSV F IgG antibody levels from pre-study product administration to the Day 56 Visit.  
Participants will be included in the analysis if they receive the as-randomized study vaccine and 
have RSV F IgG results at screening and the Day 56 Visit. These data will be summarized using 
the same methods as for the primary initial response to vaccine immunogenicity outcome 
measure.  
 
Titers of serum RSV F IgG and serum RSV-neutralizing antibodies will be summarized at the 
Day 56 Visit, as well as changes from pre-study product administration. Levels and changes will 
be compared between vaccines using pair-wise Wilcoxon rank sum tests. Sensitivity analyses will 
be performed replacing the selected child by other siblings or other children living in the same 
household who enrolled on the same date. If relevant, seasonal effects will be examined using 
analyses stratified by calendar year of enrollment.  
 
The frequency and severity of RSV-associated MAARI and MAALRI in children who experience 
these conditions during the subsequent RSV season will be summarized within each arm. Event 
rates may need to be adjusted for the varying length of the RSV surveillance season across sites. 
Supportive analyses that stratify by time of enrollment will also be performed to account for 
potential ascertainment differences related to COVID-19.   
 
9.5.4 
Exploratory Outcome Measures 
 
Participants who experience solicited AEs (Days 0-28) and serious AEs (Days 0-56) are required 
to have a nasal swab specimen collected. Viral shedding will initially be summarized at the 
participant level, with additional analyses done depending on observed patterns.     
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 78 of 106 
28 April 2022 
Other continuous exploratory outcome measures (infectivity, titers, etc.) will use methods similar 
to the secondary continuous immunogenicity outcome measures. 
 
Day 28 and 56 Visit antibody levels will be summarized using means/geometric means and 95% 
confidence intervals.  It is unlikely that formal equivalence can be established with the relatively 
small sample size.   
 
10 
DATA HANDLING AND RECORD KEEPING 
 
10.1 
Data Management Responsibilities 
 
As described in Section 4.4, data on screening and enrollment in this study will be collected using 
the DMC Study Enrollment System (SES).   
 
Study sites must maintain adequate and accurate research records containing all information 
pertinent to the study for all screened and enrolled participants, including paper-based CRFs (if 
used), eCRFs, and supporting source data. In maintaining these records, sites must comply with 
the standards of source documentation specified in the DAIDS Site Clinical Operations and 
Research Essentials (SCORE) Manual, which is available on the website referenced in Section 
10.2. 
 
eCRFs and an eCRF completion guide will be made available to study sites by the DMC. Study 
site staff will enter required data into eCRFs, with system checks applied and data queries 
generated immediately upon saving the entered data. Data must be entered within timeframes 
specified by the DMC; queries must also be resolved in a timely manner. Selected laboratory data 
will be transferred electronically to the DMC through the LDMS.  
 
The Protocol Team and/or study oversight bodies (e.g., DSMB) may determine that additional 
source data associated with procedures or evaluations performed per protocol should be entered 
into eCRFs so that the data can be used for analysis or to otherwise assist with interpretation of 
study findings. In such cases, sites will be officially instructed to enter the additional data into 
eCRFs from available source documentation.  
 
Further information on eCRFs and IMPAACT data management procedures will be provided by 
the DMC. A User Manual for the Study Enrollment System (SES) is available on the DMC portal 
at https://www.frontierscience.org. 
 
10.2 
Essential and Source Documents and Access to Source Data 
 
All DAIDS policies referenced in this section are available at: 
https://www.niaid.nih.gov/research/daids-clinical-site-implementation-operations 
 
Study-related documentation will be completed as required by applicable IRBs, the sponsor, and 
regulatory authorities. Continuing review documentation will be submitted to applicable IRBs. 
An annual report will be submitted by the sponsor to the FDA based on the anniversary date that 
the IND for the RSV ΔNS2/Δ1313/I1314L, RSV 6120/ΔNS2/1030s, and RSV 276 vaccines went 
into effect. These reports will provide a brief description of the progress of the investigation as 
outlined in 21 CFR 312.33 and will include any revisions of the protocol not previously 
submitted to the FDA. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 79 of 106 
28 April 2022 
Study-related documents will be maintained by the site investigator for a period of at least 2 years 
after final marketing approval of the vaccine, or at least 2 years after the formal discontinuation 
of clinical development of the product (or longer based upon local laws). The sponsor is required 
to inform the site investigator as to when such documents need no longer be retained. No study 
document should be destroyed without prior written agreement between the sponsor and the 
Protocol Chair. Storage of all study-related documents will be such that confidentiality will be 
strictly maintained. These records are also to be maintained in compliance with IRB, state, and 
federal medical records retention requirements, whichever are longest. Should the site 
investigator wish to assign the study records to another party and/or move them to another 
location, the site investigator must provide written notification of such intent to the sponsor with 
the name of the person who will accept responsibility for the transferred records and/or their new 
location. The sponsor must be notified in writing, and written permission must be received by the 
site from the sponsor prior to destruction or relocation of research records. 
 
All study records must be accessible for inspection, monitoring, and/or auditing during and after 
the conduct of the study by authorized representatives of the study sponsors and their contracted 
monitors, IMPAACT, the US Food and Drug Administration, the European Medicines Agency 
(EMA), site drug regulatory authorities, the sIRB and any applicable local IRBs, OHRP, and 
other US, local, and international regulatory entities. Records must be kept on site throughout the 
period of study implementation; thereafter, instructions for off-site storage may be provided by 
NIH. No study records may be removed to an off-site location or destroyed prior to receiving 
approval from NIH.  
 
10.3 
Clinical Investigator’s Brochure 
 
Investigators will receive the current version of the Clinical Investigator’s Brochures (Ibs) that 
comprehensively describe all the available preclinical experience with each experimental vaccine. 
If relevant new information becomes available during the course of the trial, the investigators will 
receive a revised IB or an amendment to the current version. 
 
10.4 
Quality Control and Quality Assurance 
 
Study sites must ensure that essential documents and participant research records are subject to 
continuous quality control and quality assurance procedures consistent with the DAIDS SCORE 
Manual, which is available on the website referenced in Section 10.2.  
 
11 
CLINICAL SITE MONITORING 
 
Under contract to DAIDS or NICHD, site monitors will inspect study site facilities and review 
participant study records – including informed consent forms, paper-based CRFs (if used), 
eCRFs, medical records, laboratory records, and pharmacy records – to ensure protection of study 
participants, compliance with the IRB/IBC-approved protocol, and accuracy and completeness of 
records. Monitors also will review essential document files to ensure compliance with all 
applicable regulatory requirements. Site investigators will make study facilities and documents 
available for inspection by the monitors.   
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 80 of 106 
28 April 2022 
Monitoring visits may be conducted on-site or remotely. Remote visits may include remote 
source document verification using methods specified for this purpose by DAIDS or NICHD. 
Remote monitoring visits may be performed in place of, or in addition to onsite visits to ensure 
the safety of study participants and data integrity (38). Site investigators will make study 
documents available for site monitors to review utilizing a secure platform that is 21 CFR Part 11 
and HIPAA compliant. Potential platform options include: Veeva SiteVault, Medidata Rave 
Imaging Solution, Medidata Remote Source Review, site-controlled SharePoint or cloud-based 
portal, and direct access to electronic medical records. Other secure platforms that are 21 CFR 
Part 11 and HIPAA compliant may be utilized, as allowed by DAIDS Office of Clinical Site 
Oversight (OCSO) or NICHD. 
 
12 
HUMAN SUBJECTS PROTECTIONS 
 
12.1 
Institutional Review Board/Ethics Committee Review and Approval  
 
Prior to study initiation, site investigators must obtain IRB/IBC review and approval of this 
protocol and site-specific ICFs in accordance with 45 CFR 46; subsequent to initial review and 
approval, IRBs/IBCs must review the study at least annually. Site investigators must promptly 
report to IRBs/IBCs any changes in the study and must comply with the requirements of 45 CFR 
46.108(a)(4) and 21 CFR 56.108(b) for promptly reporting the following: unanticipated problems 
involving risks to participants or others; serious or continuing noncompliance with applicable 
regulations or the requirements or determinations of their IRBs/IBCs; and any suspension or 
termination of IRB approval. 
 
US sites are overseen by an sIRB, with additional review by local IRBs if required per their 
agreements with the sIRB. Site investigators are responsible for awareness of and adherence to 
the policies and procedures of all applicable IRBs/IBCs. All such policies and procedures must be 
followed and complete documentation of all correspondence to and from all applicable 
IRBs/IBCs must be maintained in site essential document files. Sites must submit documentation 
of both initial review and approval and continuing review to the DAIDS Protocol Registration 
Office (PRO) in accordance with the DAIDS Protocol Registration Manual (see also Section 
13.2). 
 
A copy of the study approval (including approval of the informed consent form) is to be 
maintained in the site investigator’s study document binder, and a copy will be supplied to the 
sponsor.  
 
During the study, applicable IRBs will be provided with all documents subject to review (i.e., 
protocol amendments, informed consent form updates, advertisements, and any written 
information that may be provided to the participant’s parents/guardians). Study progress reports 
will be made to applicable IRBs in accordance with IRB guidelines and government regulations. 
 
12.2 
Vulnerable Participants 
 
The NIH is mandated by law to ensure that children be included in clinical research when 
appropriate (39, 40). This study responds to that mandate and will provide clinical research data 
to inform RSV vaccine safety and immunogenicity in children. Nonetheless, the children who 
take part in this study are considered vulnerable participants per the US Code of Federal 
Regulations, the IRBs/IBCs must consider the potential risks and benefits to child participants as 
described in 45 CFR 46 Subpart D (for children). 

 
IMPAACT 2021, FINAL Version 3.0 
Page 81 of 106 
28 April 2022 
 
With respect to 45 CFR 46 Subpart D, IRBs/IBCs must determine the level of risk to children in 
the categories specified in 45 CFR 46.404-407. Documentation of this determination is required 
to complete the DAIDS protocol registration process described in Section 13.2, and the risk 
category assigned by the IRB/IBC further determines the parental informed consent requirements 
for the study at each site.  Per 45 CFR 46.408 (b), the IRB/IBC may find that the consent of one 
parent is sufficient for research to be conducted under 46.404 or 46.405. If the IRB/IBC finds that 
the research is covered by 46.406 or 46.407, both parents must give their consent, unless one 
parent is deceased, unknown, incompetent, or not reasonably available or when only one parent 
has legal responsibility for the care and custody of the child (as determined locally). The IRB/IBC 
must document their risk determination, and study sites should adapt the signature pages of their 
site-specific ICFs as needed to accommodate the parental consent requirements associated with 
the IRB/IBC determination. 
 
Study sites must comply DAIDS requirements for enrolling minors in clinical research as 
specified in the DAIDS SCORE Manual, which is available on the website referenced in Section 
10.2.  
 
12.3 
Informed Consent 
 
A sample informed consent form is provided in Appendix VI. In obtaining and documenting 
informed consent, the site investigator must comply with the applicable regulatory requirements, 
ICH GCP guidelines, and ethical principles. The written informed consent form must be approved 
by the sIRB prior to its use. 
 
Written informed consent for the child’s study participation will be obtained before any study-
specific procedures are performed. The informed consent process will include information 
exchange, detailed discussion, and assessment of understanding of all required elements of 
informed consent, including the potential risks, benefits, and alternatives to study participation.  
The process will emphasize the unproven efficacy of the study vaccine products. 
  
As part of the informed consent process, parents/guardians will also be asked whether they agree 
to storage and future research testing of biological specimens remaining after all protocol-
specified testing has been completed. Future research testing of residual specimens may be 
declined with no impact on other aspects of the child’s study participation.   
 
Parental consenting requirements at each site will depend on the IRB/IBC risk determination 
described in Section 12.2; all IRB/IBC requirements will be followed.   
 
12.4 
Potential Benefits 
 
Participants may not receive direct study product-related benefit from enrollment in this 
study. However, based on prior studies, there is the possibility of a reduced risk of disease from 
RSV for vaccine recipients; placebo recipients will not receive any direct benefit from enrollment 
in this study. The three vaccines included in this study have been tested on small numbers of 
children, with Phase I data available/pending as outlined in protocol Section 1.3.3. The existing 
data suggest the vaccines lead to immunogenicity, but a reduced risk of disease has not been 
demonstrated so far; the prospect of direct benefit for participants is therefore uncertain. It is 
hoped that information gained in this study will contribute to the development of a safe and 
effective vaccine for the prevention of illness associated with RSV infection. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 82 of 106 
28 April 2022 
12.5 
Potential Risks  
 
The burden of repeat study visits and examinations may be a risk associated with study 
participation. Additional potential risks are summarized below. 
 
12.5.1 Venipuncture 
 
As outlined in Appendix I and Appendix II, each participant will have four scheduled blood 
draws of 5 mL each. Risks occasionally associated with venipuncture include pain and bruising at 
the site of venipuncture, lightheadedness, infection, and syncope (rarely).  
 
12.5.2 Nasal Swabs 
 
As outlined in Appendix I and Appendix II, one nasal swab (anterior nares swab) will be 
collected at each Illness Visit; note that, for possible LRI during the Acute Phase, a follow-up 
nasal swab is to be collected (see Section 6.8). Nasal swabs may be collected by participants’ 
parents/guardians and will be retrieved by study staff or returned to the study site. The total 
number of nasal swabs performed for each participant during study participation will depend on 
how many times the participant meets illness criteria. Risks occasionally associated with nasal 
swab include discomfort and occasionally epistaxis. Nasal swabs are not standard care in well 
children and are not routinely performed on ill children.   
 
12.5.3 Receipt of Study Product 
 
If a vaccine (RSV ΔNS2/Δ1313/I1314L or RSV 6120/ΔNS2/1030s) is insufficiently attenuated, 
participants could experience rhinorrhea, cough, fever, hoarseness, otitis media, or LRI. 
Immediate hypersensitivity reactions—which could be life threatening—including urticaria, 
anaphylaxis, or other Immunoglobulin E (IgE)-mediated responses are possible, as with any 
vaccine. There is a theoretical possibility, as with any investigational vaccine, of risks about 
which there is no present knowledge. Parents/guardians will be informed of any such risks should 
further data become available. As noted in Section 1.4, the RSV 276 vaccine arm was closed to 
further enrollment under protocol V2.0 and remains closed under protocol V3.0; RSV 
ΔNS2/Δ1313/I1314L and RSV 6120/ΔNS2/1030s will continue to be evaluated to determine 
which study arms will remain open in IMPAACT 2021 as outlined in Table 3 and Table 4. 
 
12.6 
Reimbursement/Compensation 
 
Pending sIRB approval, compensation will be provided to the participant’s parent/guardian based 
on each site’s standard. Specific compensation amounts will be determined by the sIRB in 
collaboration with local IRB. The amount must be reviewed and approved by the sIRB. 
Compensation will be specified in site-specific ICFs and/or other materials if applicable per IRB 
policies and procedures. 
 
12.7 
Privacy and Confidentiality 
 
All study procedures will be conducted in private and every effort will be made to protect 
participant privacy and confidentiality to the extent possible. Participant information will not be 
released without written permission to do so except as necessary for review, monitoring, and/or 
auditing as described in Section 10.2. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 83 of 106 
28 April 2022 
All study-related information will be stored securely. Participant research records will be stored 
in locked areas with access limited to study staff. All laboratory specimens, eCRFs, and other 
documents that may be transmitted off-site (e.g., EAE report forms, photographs of observed 
reactions) will be identified by PID only. Likewise, communications between study staff and 
Protocol Team members regarding individual participants will identify participants by PID only.   
 
Study sites are encouraged but not required by DAIDS to store study records that bear participant 
names or other personal identifiers separately from records identified by PID. All local databases 
must be secured with password protected access systems. Lists, logbooks, appointment books, 
and any other documents that link PID numbers to personal identifying information should be 
stored in a separate, locked location in an area with limited access.   
 
In addition to the above, a Certificate of Confidentiality has been deemed issued for the 
IMPAACT Network by the US Department of Health and Human Services. This certificate 
protects study staff from being compelled to disclose study-related information by any US 
Federal, state, or local civil, criminal, administrative, legislative, or other proceedings. It thus 
serves to protect the identity and privacy of study participants.  
 
12.8 
Management of Incidental Findings 
 
Site clinicians will inform parents (or other authorized guardians if applicable) of all clinically 
meaningful physical exam findings and laboratory test results. When applicable, site clinicians 
will provide referrals to non-study sources of medical care for further evaluation and/or treatment 
of these findings.  
 
13 
ADMINISTRATIVE PROCEDURES 
 
13.1 
Regulatory Oversight 
 
This study is sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), 
Eunice Kennedy Shriver National Institute of Child Health and Development (NICHD), and 
National Institute of Mental Health (NIMH), which are part of the United States National 
Institutes of Health (NIH).   
 
The Division of AIDS (DAIDS) within the NIAID is responsible for regulatory oversight of this 
study and holds the Investigational New Drug (IND) application under which the study will be 
conducted. DAIDS will distribute safety-related information pertaining to the study products prior 
to and during the conduct of the study, in accordance with its sponsor obligations.  
 
NIAID and NICHD provide funding to the clinical research sites at which this study will be 
conducted. Each institute contracts with an independent clinical site monitoring group to perform 
clinical site monitoring as described in Section 11. As part of this activity, monitors will inspect 
study-related documentation to ensure compliance with applicable US, local, and international 
regulatory requirements. 
 
13.2 
Protocol Registration 
 
Prior to implementation of this protocol, and any subsequent full version amendments, each site 
must have the protocol and the protocol ICFs approved by the sIRB and, as applicable, by their 
local IRBs/IBCs, and any other applicable regulatory entities. Upon receiving final approval, sites 

 
IMPAACT 2021, FINAL Version 3.0 
Page 84 of 106 
28 April 2022 
will submit all required protocol registration documents to the DAIDS PRO at the RSC. The 
DAIDS PRO will review the submitted protocol registration packet to ensure that all of the 
required documents have been received.   
 
Site-specific ICFs will be reviewed and approved by the DAIDS PRO and sites will receive an 
Initial Registration Notification from the DAIDS PRO that indicates successful completion of the 
protocol registration process. A copy of the Initial Registration Notification should be retained in 
the site's regulatory files. 
 
For any future protocol amendments, upon receiving final sIRB and any other applicable 
regulatory entity approvals, sites should implement the amendment immediately. Sites are 
required to submit an amendment registration packet to the DAIDS PRO at the RSC. The DAIDS 
PRO will review the submitted protocol registration packet to ensure that all the required 
documents have been received. Site-specific ICFs will not be reviewed and approved by the 
DAIDS PRO and sites will receive an Amendment Registration Notification when the DAIDS 
PRO receives a complete registration packet. A copy of the Amendment Registration Notification 
should be retained in the site's regulatory files. 
 
For additional information on the protocol registration process and specific documents required 
for initial and amendment registrations, refer to the current version of the DAIDS Protocol 
Registration Manual, which is available on the RSC website: https://rsc.niaid.nih.gov/clinical-
research-sites/protocol-registration. 
 
13.3 
Study Implementation 
 
This study will be conducted in accordance with the protocol, international good clinical practice 
guidelines, and all applicable US, local, and international regulations. Study implementation will 
also be guided by the IMPAACT Network MOP, study-specific MOP, LPC, and other study 
implementation materials, which will be available on the IMPAACT website: 
www.impaactnetwork.org. 
 
Study implementation at each site will also be guided site-specific SOPs. The DAIDS SCORE 
Manual specifies the minimum set of SOPs that must be established at sites conducting DAIDS 
funded and/or sponsored clinical trials (available on the website referenced in Section 10.2). 
These SOPs should be updated and/or supplemented as needed to describe roles, responsibilities, 
and procedures for this study. 
 
13.4 
Protocol Deviation Reporting 
 
Per the requirements for source documentation specified in the DAIDS SCORE Manual 
(available at the website referenced in Section 10.2), all protocol deviations must be documented 
in participant research records. Reasons for the deviations and corrective and preventive actions 
taken in response to the deviations should also be documented. 
 
Deviations should be reported to applicable IRBs/IBCs and other applicable review bodies in 
accordance with the policies and procedures of these review bodies. Serious deviations that are 
associated with increased risk to one or more study participants and/or significant impacts on the 
integrity of study data must also be reported within IMPAACT, following procedures specified in 
the IMPAACT Manual of Procedures. 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 85 of 106 
28 April 2022 
13.5 
ClinicalTrials.gov 
 
The NIH Policy on Dissemination of NIH-funded Clinical Trial Information establishes the 
expectation that clinical trials funded in whole or in part by the NIH will be registered and have 
summary results information submitted to ClinicalTrials.gov for public posting. The Protocol 
Team will comply with this policy as well as the requirements of 42 CFR 11. 
 
14 
PUBLICATIONS 
 
All presentations and publications of data collected in this study are governed by IMPAACT 
policies, which are available in the IMPAACT Network MOP. Any presentation, abstract, or 
manuscript will be made available for review by the pharmaceutical and NIAID sponsors prior to 
submission. Publication or presentation clearance will conform to any CRADA or other 
collaborative agreement in place. 
 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 86 of 106 
28 April 2022 
15 
REFERENCES 
 
1. 
Nair H, Nokes DJ, Gessner BD, Dherani M, Madhi SA, Singleton RJ, et al. Global 
burden of acute lower respiratory infections due to respiratory syncytial virus in young 
children: a systematic review and meta-analysis. Lancet. 2010;375(9725):1545-55. 
2. 
Wright PF, Karron RA, Belshe RB, Shi JR, Randolph VB, Collins PL, et al. The absence 
of enhanced disease with wild type respiratory syncytial virus infection occurring after 
receipt of live, attenuated, respiratory syncytial virus vaccines. Vaccine. 
2007;25(42):7372-8. 
3. 
Collins PL, Murphy BR. New generation live vaccines against human respiratory 
syncytial virus designed by reverse genetics. ProcAm ThoracSoc. 2005;2(2):166-73. 
4. 
Buchholz UJ, McFarland EJ, Cunningham CK, Muresan P, Perlowski C, Luongo C, et al. 
Live RSV vaccine candidates attenuated by M2-2 or NS2 deletion are well-tolerated and 
immunogenic in RSV seronegative children and infants.  RSV Vaccines for the World; 
November 29-December 1, 2017; Malaga, Spain2017. 
5. 
Bermingham A, Collins PL. The M2-2 protein of human respiratory syncytial virus is a 
regulatory factor involved in the balance between RNA replication and transcription. 
ProcNatlAcadSciUSA. 1999;96(20):11259-64. 
6. 
Karron RA, Luongo C, Thumar B, Loehr KM, Englund JA, Collins PL, et al. A gene 
deletion that up-regulates viral gene expression yields an attenuated RSV vaccine with 
improved antibody responses in children. Sci Transl Med. 2015;7(312):312ra175. 
7. 
McFarland EJ, Karron RA, Muresan P, Cunningham CK, Valentine ME, Perlowski C, et 
al. Live-Attenuated Respiratory Syncytial Virus Vaccine Candidate With Deletion of 
RNA Synthesis Regulatory Protein M2-2 is Highly Immunogenic in Children. J Infect 
Dis. 2018. 
8. 
Hall CB, Weinberg GA, Iwane MK, Blumkin AK, Edwards KM, Staat MA, et al. The 
burden of respiratory syncytial virus infection in young children. N Engl J Med. 
2009;360(6):588-98. 
9. 
Hall CB. Respiratory syncytial virus and parainfluenza virus. N Engl J Med. 
2001;344(25):1917-28. 
10. 
Martinez FD. Respiratory syncytial virus bronchiolitis and the pathogenesis of childhood 
asthma. PediatrInfect DisJ. 2003;22(2 Suppl):S76-S82. 
11. 
Collins PL, Karron RA. Respiratory syncytial virus and metapneumovirus. In: Knipe 
DM, Howley PM, Cohen JI, Griffin DE, Lamb RA, Martin MA, et al., editors. Fields 
Virology, Sixth Edition. 1. Sixth ed. Philadelphia: Lippincott Williams & Wilkins; 2013. 
p. 1086-123. 
12. 
Kim HW, Canchola JG, Brandt CD, Pyles G, Chanock RM, Jensen K, et al. Respiratory 
syncytial virus disease in infants despite prior administration of antigenic inactivated 
vaccine. Am J Epidemiol. 1969;89(4):422-34. 
13. 
Collins PL, Murphy BR. Vaccines against Human Respiratory Syncytial Virus. 
Respiratory Syncytial Virus. 2007;14:233-78. 
14. 
Acosta PL, Caballero MT, Polack FP. Brief history and characterization of enhanced 
respiratory syncytial virus disease. Clin Vaccine Immunol. 2015;23(3):189-95. 
15. 
Karron RA, Wright PF, Belshe RB, Thumar B, Casey R, Newman F, et al. Identification 
of a recombinant live attenuated respiratory syncytial virus vaccine candidate that is 
highly attenuated in infants. J Infect Dis. 2005;191(7):1093-104. 

 
IMPAACT 2021, FINAL Version 3.0 
Page 87 of 106 
28 April 2022 
16. 
Hendry RM, Burns JC, Walsh EE, Graham BS, Wright PF, Hemming VG, et al. Strain-
specific serum antibody responses in infants undergoing primary infection with 
respiratory syncytial virus. J Infect Dis. 1988;157(4):640-7. 
17. 
Johnson PR, Jr., Olmsted RA, Prince GA, Murphy BR, Alling DW, Walsh EE, et al. 
Antigenic relatedness between glycoproteins of human respiratory syncytial virus 
subgroups A and B: evaluation of the contributions of F and G glycoproteins to 
immunity. J Virol. 1987;61(10):3163-6. 
18. 
Collins PL, Hill MG, Camargo E, Grosfeld H, Chanock RM, Murphy BR. Production of 
infectious human respiratory syncytial virus from cloned cDNA confirms an essential 
role for the transcription elongation factor from the 5' proximal open reading frame of the 
M2 mRNA in gene expression and provides a capability for vaccine development. 
ProcNatlAcadSciUSA. 1995;92(25):11563-7. 
19. 
Luongo C, Winter CC, Collins PL, Buchholz UJ. Increased genetic and phenotypic 
stability of a promising live-attenuated respiratory syncytial virus vaccine candidate by 
reverse genetics. Journal of virology. 2012;86(19):10792-804. 
20. 
Luongo C, Winter CC, Collins PL, Buchholz UJ. Respiratory syncytial virus modified by 
deletions of the NS2 gene and amino acid S1313 of the L polymerase protein is a 
temperature-sensitive, live-attenuated vaccine candidate that is phenotypically stable at 
physiological temperature. Journal of virology. 2013;87(4):1985-96. 
21. 
Whitehead SS, Bukreyev A, Teng MN, Firestone CY, St Claire M, Elkins WR, et al. 
Recombinant respiratory syncytial virus bearing a deletion of either the NS2 or SH gene 
is attenuated in chimpanzees. Journal of virology. 1999;73(4):3438-42. 
22. 
Valarcher JF, Furze J, Wyld S, Cook R, Conzelmann KK, Taylor G. Role of alpha/beta 
interferons in the attenuation and immunogenicity of recombinant bovine respiratory 
syncytial viruses lacking NS proteins. Journal of virology. 2003;77(15):8426-39. 
23. 
Jin H, Cheng X, Zhou HZ, Li S, Seddiqui A. Respiratory syncytial virus that lacks open 
reading frame 2 of the M2 gene (M2-2) has altered growth characteristics and is 
attenuated in rodents. J Virol. 2000;74(1):74-82. 
24. 
Teng MN, Whitehead SS, Bermingham A, St CM, Elkins WR, Murphy BR, et al. 
Recombinant respiratory syncytial virus that does not express the NS1 or M2-2 protein is 
highly attenuated and immunogenic in chimpanzees. J Virol. 2000;74(19):9317-21. 
25. 
Karron RA, Wright PF, Crowe JE, Jr., Clements-Mann ML, Thompson J, Makhene M, et 
al. Evaluation of two live, cold-passaged, temperature-sensitive respiratory syncytial 
virus vaccines in chimpanzees and in human adults, infants, and children. J Infect Dis. 
1997;176(6):1428-36. 
26. 
Wright PF, Karron RA, Belshe RB, Thompson J, Crowe JE, Jr., Boyce TG, et al. 
Evaluation of a live, cold-passaged, temperature-sensitive, respiratory syncytial virus 
vaccine candidate in infancy. J Infect Dis. 2000;182(5):1331-42. 
27. 
Wright PF, Karron RA, Madhi SA, Treanor JJ, King JC, O'Shea A, et al. The interferon 
antagonist NS2 protein of respiratory syncytial virus is an important virulence 
determinant for humans. J Infect Dis. 2006;193(4):573-81. 
28. 
McFarland EJ, Karron RA, Muresan P, Cunningham CK, Valentine ME, Perlowski C, et 
al. Live-Attenuated Respiratory Syncytial Virus Vaccine Candidate With Deletion of 
RNA Synthesis Regulatory Protein M2-2 is Highly Immunogenic in Children. The 
Journal of infectious diseases. 2018;217(9):1347-55. 

 
IMPAACT 2021, FINAL Version 3.0 
Page 88 of 106 
28 April 2022 
29. 
McFarland EJ, Karron RA, Muresan P, Cunningham CK, Perlowski C, Libous J, et al. 
Live-Attenuated Respiratory Syncytial Virus Vaccine With M2-2 Deletion and With 
Small Hydrophobic Noncoding Region Is Highly Immunogenic in Children. J Infect Dis. 
2020;221(12):2050-9. 
30. 
McFarland EJ, Karron RA, Muresan P, Cunningham CK, Libous J, Perlowski C, et al. 
Live Respiratory Syncytial Virus Attenuated by M2-2 Deletion and Stabilized 
Temperature Sensitivity Mutation 1030s Is a Promising Vaccine Candidate in Children. J 
Infect Dis. 2020;221(4):534-43. 
31. 
Cunningham CK, Karron R, Muresan P, McFarland EJ, Perlowski C, Libous J, et al. 
Live-Attenuated Respiratory Syncytial Virus Vaccine With Deletion of RNA Synthesis 
Regulatory Protein M2-2 and Cold Passage Mutations Is Overattenuated. Open Forum 
Infect Dis. 2019;6(6):ofz212. 
32. 
McFarland EJ, Buchholz UJ, Muresan P, Cunningham CK, Luongo C, Thumar B, et al., 
editors. High Infectivity of recombinant live-attenuated respiratory syncytial virus 
vaccine RSV LID ΔM2-2 in RSV-seronegativeinfants and children. ID Week Advancing 
Science, Improving Care; 2015; San Diego, CA. 
33. 
American Academy of Pediatrics, Committee on Practice and Ambulatory Medicine. 
Recommendations for Preventive Pediatric Health Care. Pediatrics. 2007;120(6):1376. 
34. 
Siberry GK, ener-West M, Schappell E, Karron RA. Comparison of temple temperatures 
with rectal temperatures in children under two years of age. ClinPediatr(Phila). 
2002;41(6):405-14. 
35. 
Crowe JE, Jr., Bui PT, London WT, Davis AR, Hung PP, Chanock RM, et al. 
Satisfactorily attenuated and protective mutants derived from a partially attenuated cold-
passaged respiratory syncytial virus mutant by introduction of additional attenuating 
mutations during chemical mutagenesis. Vaccine. 1994;12(8):691-9. 
36. 
Whitehead SS, Juhasz K, Firestone CY, Collins PL, Murphy BR. Recombinant 
respiratory syncytial virus (RSV) bearing a set of mutations from cold-passaged RSV is 
attenuated in chimpanzees. J Virol. 1998;72(5):4467-71. 
37. 
Gharpure MA, Wright PF, Chanock RM. Temperature-sensitive mutants of respiratory 
syncytial virus. J Virol. 1969;3(4):414-21. 
38. 
FDA Guidance on Conduct of Clinical Trials of Medical Products During the COVID-19 
Public Health Emergency: Guidance for Industry, Investigators, and Institutional Review 
Boards. March 2020 [updated January 27, 2021. Available from: 
https://www.fda.gov/media/136238/download. 
39. 
National Institutes of Health. Guidelines for the Inclusion of Women and Minorities as 
Subjects in Clinical Research. Federal Register.; 1994 March 18. 
40. 
National Institutes of Health. NIH Policy and Guidelines on the Inclusion of Children as 
Participants in Research Involving Human Subjects. 1998 March 6. 
 

 
  
 
IMPAACT 2021, FINAL Version 3.0 
Page 89 of 106 
28 April 2022 
APPENDICES 
Appendix I: Schedule of Events: Screening, Acute Phase, and Post-Acute Phase  
 
* Select Illness Visits can be conducted via telehealth (See Section 6.8) 
 
 
ACUTE PHASE 
POST-ACUTE PHASE 
 
Screening 
Enrollment 
Visit/Study Product 
Administration 
(Day 0) 
Day 1-27  
(contact each day 
±1 day) 
Day 28  
(-1/+4 days) 
Day 29  
(+1 day) 
Day 29 to Day 56 
Visit (monitoring 
throughout) 
Day 56 
(+7 days) 
Day 57 
Illness Visit  
Early 
Discontinuation 
In-person visit (all 
except Day 0 may 
be in clinic or home) 
X 
X 
 
X 
 
 
X 
 
X* 
X 
Non-visit contact 
 
 
X 
 
X 
Per 
Section 
6.4 
 
If needed 
per Section 
6.4.2 
 
 
Informed consent 
X 
 
 
 
 
 
 
 
 
 
History 
X 
 
 
 
 
 
 
 
 
 
Interim history 
 
X 
X 
X 
X 
Per 
Section 
6.4 
X 
If needed 
per Section 
6.4.2 
X 
X 
Physical exam (full) 
 
X 
 
 
 
 
 
 
 
 
Clinical assessment 
(focused PE) 
X 
 
 
X 
 
 
 
 
X 
 
Administer study 
product 
 
X 
 
 
 
 
 
 
 
 
Blood for: 
immunologic assays 
5mL 
If needed 
per  
Section 6.2 
 
5mL 
 
 
5mL 
 
 
5mL 
Nasal swab for 
viral detection & 
quantification 
 
 
 
 
 
 
 
 
X 
 
Total blood volume 
5mL 
-- 
-- 
5mL 
-- 
-- 
5mL 
 
-- 
5mL 

 
IMPAACT 2021, FINAL Version 3.0 
Page 90 of 106 
28 April 2022 
Appendix II: Schedule of Events: RSV Seasonal Surveillance and Post-season 
Sampling 
 
 
Weekly contact 
Post-RSV Season 
Visit 
Illness 
Visit*** 
Early 
Discontinuation 
Visit Period 
Nov 1st* to Mar 31st 
Apr 1st to Apr 
30th** 
 
 
Clinical assessment 
(focused PE) 
 
 
X 
 
Interim history 
X 
 
X 
X 
LABORATORY EVALUATIONS 
Blood for: 
immunologic assays 
 
5 mL 
 
5 mL 
Nasal swab for 
viral detection & 
quantification 
 
 
X 
 
TOTAL BLOOD 
VOLUME 
-- 
5 mL 
-- 
5 mL 
*These dates apply to most sites but may differ for those with local RSV seasons that differ. 
** For sites experiencing disruptions or limitations of usual operations due to COVID-19, broadened visit 
window specifications for this visit are provided in Appendix V. 
*** Select Illness Visits can be conducted via telehealth (See Section 6.8) 
 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 91 of 106 
28 April 2022 
Appendix III: Definitions of Solicited Adverse Events 
 
Event 
Defined 
Fever 
Temporal temperatures ≥100.0oF unconfirmed by rectal temp -or-  
Rectal temperature of ≥100.4oF. 
Acute Otitis Media1 
Loss of tympanic membrane landmarks, accompanied by erythema and loss 
of mobility. May or may not be associated with fever or other respiratory 
symptoms. Confirmed with tympanometry if possible. 
Upper Respiratory Tract Illness (URI) 
Rhinorrhea 
Two or more consecutive days of clear or purulent discharge from the 
nares.  
Note: Not associated with crying, change of room temperature, or eating 
and drinking. 
Pharyngitis1 
Pharyngeal erythema accompanied by exudate or pharyngeal erythema with 
enlarged tender lymph nodes.   
Note: May be associated with sore throat, or painful or difficult swallowing. 
Cough without LRI  
Two or more consecutive days of 3 or more episodes of cough during a 15-
minute timed observation period, or cough awakens child from sleep.  
Note: Not associated with eating, drinking or choking. 
Hoarseness 
An unnaturally deep or rough quality of voice. 
Lower Respiratory Tract Illness (LRI) 
Wheezing2,3 
Sustained, high pitched, musical breath sounds, especially during the 
expiratory phase, which do not clear with cough. 
Pneumonia1,2,3 
Rales and crackles, originating in the lower respiratory tract, usually 
accompanied by tachypnea, which do not clear with cough. May be 
confirmed by x-ray showing areas of consolidation. 
Laryngotracheobronchitis 
(croup) 1,2,4 
Barking cough, hoarseness, and inspiratory stridor 
Rhonchi2,3 
Coarse breath sounds which are not transmitted noises from the upper 
airway and do not clear with cough. 
Rales2,3 
Abnormal lung sound heard through a stethoscope. Rales may be sibilant 
(whistling), dry (crackling) or wet (more sloshy) depending on the amount 
and density of fluid refluxing back and forth in the air passages. 
1 Diagnosis must be made by a medical professional 
2 Must be sustained over 20 minutes. 
3 Clinical assessment must be made by a medical professional and confirmed by a second medical professional, if possible. 
4 It is not necessary for medical professional(s) to witness inspiratory stridor as long as parent or guardian report is consistent 
with stridor and a medical professional judges the symptoms in total to be consistent with croup. 
 
NOTE: Solicited AEs will only be entered into eCRFs according to guidance outlined in Section 7.2.

 
IMPAACT 2021, FINAL Version 3.0 
Page 92 of 106 
28 April 2022 
Appendix IV: RSV Seasonality in Baltimore 
 
 
 
 
 
 
 
 
All specimens collected and tested at Johns Hopkins Hospital through 10 March 2016 
 
 

 
IMPAACT 2021, FINAL Version 3.0 
Page 93 of 106 
28 April 2022 
Appendix V: Operational Guidance for Study Implementation at Sites 
Experiencing Operational Disruptions Due to COVID-19  
 
To safeguard the health and well-being of study participants and study staff in the context of circulating 
SARS-CoV-2 and the associated coronavirus disease 2019 (COVID-19), the guidance provided in this 
appendix may be implemented at sites experiencing disruptions due to COVID-19.  
 
The extent to which site operations may be disrupted by COVID-19 may vary across sites and over time. 
All sites should follow applicable government, health authority, and institutional policies with 
respect to conduct of study visits and procedures, with utmost importance placed on the health and 
well-being of study participants and study staff. All sites must also comply with any directives 
received from the study sponsor, the IMPAACT Network, the IMPAACT 2021 the Protocol Team and/or 
Protocol Safety Review Team (PSRT) and should contact the PSRT (impaact.psrt2021@fstrf.org) with 
any questions or concerns regarding this guidance or management of study participants.  
 
Should a determination be made in the future that the guidance provided in this appendix is no longer 
applicable, sites will be formally notified and instructed to inform their IRBs and other applicable 
regulatory entities. 
 
Visit Scheduling 
• 
Sites should continue to conduct weekly non-visit contacts per protocol with participants’ families 
during the remainder of RSV Season Surveillance (i.e., through 31 March in a given year). 
• 
Should sites have research visits suspended due to COVID-19, data should be collected via chart 
abstractions. The participants’ parents/guardians may collect nasal swab specimens as directed by the 
site staff.  
• 
Sites should conduct Post-RSV Season Study Visits; effective when sites experience disruption due to 
COVID-19 and implement this guidance, the target window for the Post-RSV Season Study Visit is 
broadened to include 1 April to 31 July in a given year and the allowable window for this visit is 
broadened to include up to 30 September in a given year.  
­ Sites should utilize the broadened visit window as needed to permit continued completion of in-
person Post-RSV Season Study Visits. 
­ Sites that anticipate operational disruptions or closures in the near future are advised to conduct 
visits early in the target window. Visits conducted prior to opening of the target window would 
also be preferred to completely missing a visit at a later date. 
­ Sites that are currently experiencing operational disruptions or closures are advised to conduct 
visits late in the target window. Visits conducted after closing of the target window (i.e., after 31 
July in a given year) but prior to the closing of the allowable window (i.e., by 30 September in a 
given year) would also be preferred to completely missed visits. 
­ Sites with no ability to conduct Post-RSV Season Study Visits in-person during any of the 
windows noted above should notify the protocol team. 
 
Prioritization of Post-RSV Season Study Visit Procedures 
• 
Sites with full capacity to conduct Post-RSV Season Study Visits in-person at the study clinic during 
the month of April in a given year should continue to do so in full compliance with the current 
protocol language. If it is not possible to conduct visits in April, the broadened windows noted above 
may be used. 
• 
Sites may also conduct in-person Post-RSV Season Study Visits off-site, in full or in part, if permitted 
by applicable government, health authority, and institutional policies during any of the windows 
noted above. Where this option is permitted, site staff should communicate with parents/guardians to 
determine in advance where and when such visits will take place, with adequate protections for 

 
  
 
IMPAACT 2021, FINAL Version 3.0 
Page 94 of 106 
28 April 2022 
safety, privacy, and confidentiality. Off-site visit procedures should be conducted by site staff who 
are adequately qualified and trained to conduct the procedures, as determined by the site Investigator 
of Record (IoR), with attention paid to occupational health, biohazard containment, and specimen and 
data chain of custody. These staff should also be adequately trained and qualified to immediately 
assess and/or manage any adverse events and/or social impacts that may occur during the visits. If 
adverse events requiring further evaluation or management are identified during an off-site visit, 
study staff conducting the visit should arrange for appropriate clinical management, in consultation 
with the IoR or designee, as needed. 
• 
The only protocol-specified procedure for the Post-RSV Season Study Visit is collection of blood for 
serum antibodies to RSV. Sites with limited capacity to conduct Post-RSV Season Study Visits in-
person with blood collection during any of the windows noted above should contact the protocol 
team.  
 
Documentation 
• 
Site-specific contingency plans, and the implementation thereof, should be documented in essential 
document files for IMPAACT 2021.  
• 
Documentation should be entered in participant study charts in real-time should any of the following 
occur: 
­ Missed visits  
­ Out-of-window visits 
­ Off-site visits (document the location of the visit) 
­ Incomplete or partial visits (document which procedures were performed and which were not) 
­ Remote contacts (e.g., by telephone) performed in lieu of in-person visits (document method used 
to complete the contact and which procedures were performed) 
­ Any other participant contacts  
­ Non-standard laboratory assays (e.g., use of alternate laboratories or alternate laboratory assays) 
• 
In consultation with the Division of AIDS, the IMPAACT Network has developed and disseminated 
guidance for documenting and/or reporting protocol deviations that may occur due to limited site 
capacity to conduct study visits or procedures due to COVID-19. Please contact the IMPAACT 
Operations Center Clinical Research Managers with any questions related to documentation and 
reporting requirements.  
 
 
 

 
  
 
IMPAACT 2021, FINAL Version 3.0 
Page 95 of 106 
28 April 2022 
Appendix VI: Informed Consent Form for Study Participation 
 
Version 3.0, dated 28 April 2022 
 
 
Sponsor / Study Title: 
  
National Institutes of Health (NIH) / National Institute of Allergy and 
Infectious Diseases (NIAID) / National Institute of Child Health and 
Human Development (NICHD) / National Institute of Mental Health 
(NIMH) / “Randomized Phase I/II Study of the Safety and 
Immunogenicity of a Single Dose of the Recombinant Live-Attenuated 
Respiratory Syncytial Virus (RSV) Vaccines RSV 
ΔNS2/Δ1313/I1314L, RSV 6120/ΔNS2/1030s, RSV 276 or Placebo, 
Delivered as Nose Drops to RSV-Seronegative Children 6 to 24 
Months of Age” 
 
Protocol Number: 
 
IMPAACT 2021  
 
Principal Investigator: 
(Study Doctor) 
 
«PiFullName» 
 
Telephone: 
 
«IcfPhoneNumber» 
 
Address: 
«PiLocations» 
 
 
 
KEY INFORMATION 
 
You are being asked to allow your child to take part in this research study to test vaccines to prevent 
respiratory syncytial virus (RSV) illness in children. Research studies include only people who choose to 
take part or whose parents/legal guardians choose to allow them to take part. The study staff will explain 
the study to you and will answer any questions you might have. You should take your time to make your 
decision. 
 
Important details you should know: 
• 
The purpose of the study is to look at the safety (side effects) and antibody (germ fighter) 
response of children to a single dose of one of two investigational vaccines against RSV. 
Investigational means that the study vaccines have not been approved for use by the U.S. Food 
and Drug Administration (FDA).  
• 
If you choose to allow your child to participate in this study, he/she will receive either 1 dose of 
one of the study vaccines or 1 dose of placebo (inactive substance), which has no study vaccine in 
it.  
• 
After the visit where your child receives the study vaccine or placebo, he/she will complete 3 
more in-person study visits, which will include answering questions about your child’s health, 
completing a physical exam on your child and collecting a small amount of blood from your 
child. In between these visits, study staff will contact you by telephone, text, or email to check on 
your child. If your child becomes ill, he/she will have a nasal swab collected to test for the RSV 
vaccine virus or any other virus that may be in your child's nose. The swab may be collected by 
you or by study staff. 

 
  
 
IMPAACT 2021, FINAL Version 3.0 
Page 96 of 106 
28 April 2022 
• 
Your child will be in this study until April of the year after he/she started the study, which is 
between 4 and 15 months from now, depending on which month of the year he/she starts the 
study. 
• 
Risks and side effects related to receipt of a study vaccine could include mild respiratory illnesses 
or colds or allergic reaction (rarely). If your child receives a nasal swab as part of the study, 
he/she could experience brief discomfort, or rarely, a nosebleed. The study blood draws could 
cause bleeding, pain, bruising, infection, and/or lightheadedness/passing out (rarely). 
• 
Your child may receive a study vaccine that may reduce RSV disease; however, your child may 
receive no direct benefit from participating in the study. This study will help doctors learn more 
about RSV, and it is hoped that this information will help in the prevention of RSV in children in 
the future. 
• 
You may choose to not allow your child to take part in this study. There are currently no licensed 
vaccines to protect against RSV illness. 
 
INTRODUCTION 
 
You are being asked to allow your child to take part in this research study to test vaccines to prevent 
respiratory syncytial virus (RSV) illness in children. This study is sponsored by the National Institutes of 
Health (NIH). The study doctor in charge of this study at this study site is listed on the first page of this 
form. Before you decide if you want your child to be a part of this study, we want you to know about the 
study.  
 
This is a consent form. It gives you information about this study. The clinical research staff will talk with 
you about this information. You are free to ask questions about this study at any time. If you agree to 
allow your child to take part in this study, you will be asked to sign and date this consent form. You will 
get a copy to keep. 
 
WHY IS THIS STUDY BEING DONE? 
 
The study is being done to look at the safety (side effects) and antibody (germ fighter) response of 
children to a single dose of one of two study vaccines against a virus called respiratory syncytial virus, or 
RSV. The study will look to see if the vaccine increases protection against RSV. It will tell us how safe 
and strong the study vaccine was during the study. The experimental vaccines in this study have not been 
approved by the US Food and Drug Administration (FDA). Your child was chosen to be in this study 
because your child is at least 6 months (180 days) old and less than 25 months (750 days) old and is 
healthy.  
 
 
RSV is a virus (germ) that can cause breathing problems in children. Symptoms of infection with RSV 
may include: 
• 
Fever 
• 
Runny nose 
• 
Sore throat 
• 
Ear infection 
• 
Cough  
• 
Croup (barky cough with hoarseness) 
 
RSV can cause serious lung infections such as pneumonia and wheezing. At this time, there is no 
approved vaccine to prevent RSV illness. 
 

 
  
 
IMPAACT 2021, FINAL Version 3.0 
Page 97 of 106 
28 April 2022 
Doctors who develop vaccines at the NIH have made live virus vaccines that may help prevent RSV 
illness in babies and children. A live virus vaccine contains a weakened, live virus that is made to help 
your body respond in a way that will protect you from getting sick from the virus. This is called an 
“immune response.” The investigational RSV vaccines in this study contain a live, weakened form of 
RSV and are given as nose drops. The study vaccines have been tested in humans before, and other RSV 
vaccines very similar to these have also been tested in both adults and children. There were not many side 
effects, and there was an immune response. 
  
We are asking you to allow your child to participate in this study. We will ask you to review, sign, and 
date this study consent prior to conducting any study procedures with your child. As part of reviewing the 
consent, we will ask you to answer questions to see how well you understand the study. If you agree that 
your child can participate, we will give your child either 1 dose of one of the study vaccines or 1 dose of 
placebo, which has no investigational vaccine in it. The placebo is made of water and salt and is gentle on 
the inside of the nose. It is sterile, which means it is very clean, and is safe to use in people. About 100 
additional children are planned to take part in the study.  
 
WHAT DOES MY CHILD HAVE TO DO IF HE/SHE IS IN THIS STUDY? 
 
General Information About the Study  
 
If you agree to allow your child to take part in this study, you will be asked some questions to be sure 
he/she can be in this study. Your child’s blood will be tested at the first visit to see if your child has had 
RSV in the past. You will be told the result of this test. Your child cannot take part in this study if he/she 
already has antibodies against RSV, which means he/she already had the RSV illness. Your child will not 
be able to be in the study if your child lives with people who have weak immune systems or is not well.  
 
Your child cannot take part in this study if you know or think that he/she has been exposed to SARS-
CoV-2, the new coronavirus that causes the COVID-19 illness, within 14 days prior to enrollment. Your 
child cannot take part in this study if he/she lives with or is in a daycare room with babies younger than 4 
months of age, unless you are able to keep your child out of daycare for 14 days after he/she receives the 
study vaccine or placebo.  
 
 Your child should not get any vaccines, including rotavirus vaccine for at least 14 days and other live 
vaccines for at least 28 days after getting the study vaccine or placebo. We ask that you talk with the 
study staff before your child gets any routine vaccines for the 28 days after the study vaccine or placebo. 
We ask that your child does not take part in any other experimental vaccine or drug studies for 8 weeks 
after they receive vaccine or placebo.  
 
The study vaccine/placebo will be given to your child as described under “Day Study Vaccine/Placebo is 
Given” below. If multiple children living in the same household are eligible to participate in the study, 
they must be enrolled on the same date, or they may enroll on different dates if additional children in the 
household are screened and enrolled after other children in the household complete the Day 56 Visit. All 
children living in the same household who are enrolled on the same date must receive the study 
vaccine/placebo on the same date. 
 
About 2 out of each 3 enrolled children will get one of the two RSV study vaccines, and about 1 out of 
each 3 enrolled children will get nose drops without vaccine (placebo). Whether your child gets one of the 
study vaccines or nose drops without vaccine (placebo) will be decided randomly by computer, like 
flipping a coin. All children living in the same household who are enrolled on the same date will be 
randomly assigned to the same study group. Neither you nor the study doctors or study nurses will know 

 
  
 
IMPAACT 2021, FINAL Version 3.0 
Page 98 of 106 
28 April 2022 
whether your child got one of the study vaccines or placebo until the study ends, but this information can 
be made available to the study doctor if needed. The graphic below shows the study groups. 
 
 
 
Your child will be in this study until April of the year after he/she started the study. For the first 8 weeks 
after getting the study vaccine or placebo, your child will be followed closely. During this part of the 
study, there will be about 2 days when your child is seen by the study staff and 28 days when your child 
will not be seen but you will be contacted by telephone, text, or email by the study staff. Your child will 
also be followed during the RSV season after your child gets the vaccine or placebo. During this time, we 
will contact you by telephone, text, or email each week to ask about your child's health and arrange for 
follow-up visits if needed.  
 
Study visits will last about 30 to 60 minutes, except on the day when your child is screened and on the 
day he/she is given the study vaccine or placebo; those 2 visits may take about 1 to 2 hours each.  
 
Please note the following for the study visits: 
 
• 
If your child has RSV symptoms, such as runny nose, sore throat, cough, fever, or difficulty 
breathing, he/she might need to be seen for an evaluation, sometimes as soon as within 24 hours. 
• 
Study visits, except the visit where your child gets the study vaccine or placebo, may take place at 
your home or at one of the research sites/clinics. The visit where your child receives the study 
vaccine or placebo must take place at one of the research sites/clinics where emergency 
equipment is available.  
• 
Other study visits may take place at your home or at one of the research sites/clinics. Study staff 
will provide you with information on the location of these visits. 
• 
For temperature measurements, you will be asked to use a temporal thermometer, which is used 
on your child’s forehead. You will measure forehead temperatures 3 times in a row, following the 
directions. The highest of the 3 readings will be recorded on a chart we will give to you. If your 
child has a forehead temperature greater than or equal to 100.0o Fahrenheit, you will be asked to 
check your child’s rectal temperature within 20 minutes. Forehead and rectal thermometers will 
be given to you for use during the study. 
 
In the sections below, we will tell you more about what will happen at the different study visits.  
 
Screening Visit 
 
The purpose of the screening visit is to find out if your child may enter the study. It will take about 1 to 2 

 
  
 
IMPAACT 2021, FINAL Version 3.0 
Page 99 of 106 
28 April 2022 
hours and will include: 
• 
The study staff telling you about the study and asking you questions to be sure you understand the 
study. 
• 
Going over, signing, and dating the consent form.   
• 
Going over your child's medical history and doing a physical examination on your child. The 
physical examination will include checking your child’s temperature, pulse (heart rate), breathing 
rate, and examination of your child’s ears, eyes, nose, throat, lungs, heart, and lymph nodes. If the 
physical examination results are not normal, the study staff will tell you and refer your child for 
follow-up care with your child's primary medical provider. If your child has had a physical 
examination recently, we may be able to record the results from his/her medical record, rather 
than doing another examination. 
• 
Answering questions about the health of your child and people living in your house. 
• 
Collecting a small amount of blood (about 1 teaspoon) to test for antibodies (germ fighters) 
against RSV. If your child had been screened for any study of an RSV vaccine developed by the 
NIH doctors, we may not need to collect this sample, because we may be able to use the results 
and blood from the other study.  
• 
If requested, giving written permission to review your child’s medical records. 
• 
If we think your child may be eligible for the study, your child will be asked to return for a series 
of study visits, beginning with the visit when we will confirm that he/she is eligible and then give 
your child the study vaccine or placebo. 
 
Day Study Vaccine/Placebo is Given 
This visit will take about 1 to 2 hours and will include the following: 
• 
We will confirm that your child has not been ill recently and do a physical examination, which 
will include checking your child’s temperature, pulse (heart rate), breathing rate, weight, length, 
head, ears, eyes, nose, throat, lungs, heart, abdomen, musculoskeletal system, nervous system, 
and skin. 
• 
Your child will receive 1 dose of study vaccine or placebo given as nose drops using a small 
syringe (without a needle). Your child will be lying on his/her back while we give a small amount 
of nose drops and into both nostrils. Your child will remain lying down for about 1 minute 
afterwards. Your child can be in your lap during this time. 
• 
After the nose drops are given, we will watch your child in the clinic for 30 minutes.  
• 
We will provide you with the dates of the rest of the visits and telephone/email contact days.  
• 
You will be given a forehead thermometer, a rectal thermometer, and a temperature chart to 
record your child's temperature daily for 29 days (including the day the study vaccine/placebo is 
given to your child), and at any other time you are concerned about fever. 
 
Monitoring for 56 Days after Study Vaccine/Placebo is Given 
• 
Your child will have a study visit on Day 28 (-1/+4 days) after the study vaccine or placebo is 
given. This visit will take about 30 to 60 minutes, and we will: 
o Check your child's temperature, pulse, breathing rate, ears, eyes, nose, throat, lungs, 
heart, and lymph nodes. 
o Do a brief clinical assessment. 
o Ask about your child's health since the last visit. 
o We will take a small amount of blood (about 1 teaspoon) from your child to measure 
antibodies (germ fighters) against RSV. 
o Because study visits will be less frequent after the first month, on Day 28, we will review 
when you should contact the study staff in the event your child becomes ill during the 
following month. 

 
  
 
IMPAACT 2021, FINAL Version 3.0 
Page 100 of 106 
28 April 2022 
• 
The study nurse will contact you daily from Days 1 through 27, and on Day 29. The study staff 
will ask you to report your child’s temperatures and any illness your child has had since the last 
visit or contact. The contact may be by telephone, text, or email, whichever you prefer.   
• 
Your child will have a follow-up visit about 56 days after the study nose drops were given. At 
this visit, we will ask about your child’s health since the last visit and take a small amount of 
blood (about 1 teaspoon) from your child to measure antibodies (germ fighters) against RSV. We 
will check your child's temperature, pulse, and breathing rate.  
• 
We also ask you to call us right away to tell us about any illness that your child has from the day 
he/she receives the nose drops up to the follow-up visit (8 weeks). 
• 
A study nurse or study doctor will be available by telephone to answer your questions 24 hours a 
day during the 28 days after your child receives the study vaccine or placebo. 
• 
If your child becomes ill, you may be asked to complete a telehealth (telephone or video) visit, an 
in-person visit with a licensed medical provider in the community, and/or bring him/her to the 
clinic for an examination, sometimes as quickly as within 24 hours. We may request your 
permission to review your child’s medical records, including records from visits with other 
medical providers related to the illness. A nasal swab will be collected at that time to look for the 
RSV vaccine virus or any other virus that may be in your child's nose. The swab may be collected 
by study staff or by you, if you are comfortable doing this. To do the nasal swab, a swab will be 
gently inserted into your child’s nose, rotated for a few seconds, and then removed. 
 
Monitoring Before, During, and After RSV Season 
• 
Your child will also be followed during the RSV season after getting the study nose drops. We 
will be in contact with you each week to inquire about your child's health. If your child has a 
fever, a respiratory illness (a cold), or an ear infection that requires medical care, we will work 
with you to schedule an in-person visit at the clinic or with a licensed medical provider in the 
community, or telehealth (telephone or video) visit, to collect a nasal swab and clinical 
assessment. We may request your permission to review your child’s medical records, including 
records from visits with other medical providers related to the illness. 
• 
We will collect a small amount of blood (about 1 teaspoon) in April of the year after he/she 
started the study to look at the antibodies (germ fighters) against natural RSV infection.  
• 
You will not be told whether your child received the study vaccine or placebo while on study. 
You will receive that information after the end of the study. You will not receive information 
about your child’s response to the study vaccine, but you will receive a summary of the overall 
response to the study vaccine for everyone in the study. 
HOW MANY PEOPLE WILL TAKE PART IN THIS STUDY? 
There will be approximately 100 additional children taking part in this study.  
WHAT ARE THE RISKS OF THE STUDY? 
Risks of the Study Vaccines 
• 
If the study vaccines are not weakened enough, they may cause a runny nose, sore throat, cough, 
or other signs of a cold. Some children who previously received a different vaccine that is no 
longer included in this study had coughs. It is also possible that the study vaccines may cause a 
sinus infection, croup (infection of the upper airway), ear infection, fever, wheezing, or 
pneumonia (infection of the lungs). In other studies with similar study vaccines, mild respiratory 
illnesses or colds were observed frequently in children who received either study vaccine or 
placebo. Runny nose occurred more often in children who got vaccine than those who got 
placebo. 

 
  
 
IMPAACT 2021, FINAL Version 3.0 
Page 101 of 106 
28 April 2022 
• 
Study investigators have used the same or similar placebo for studies of RSV, parainfluenza 
(virus causing cold, pneumonia, bronchitis, etc.), and influenza (flu) vaccines in several hundred 
babies and children over the past 20 years. They have not noticed side effects with this placebo.   
• 
There is no specific medicine to treat RSV illness. If any symptoms of RSV occur, such as runny 
nose, sore throat, cough, or difficulty breathing, your child will receive prompt medical care, if 
needed. 
• 
The study vaccines were made in a way that was designed to minimize the inclusion of other 
ingredients. However, as with all biological products, there is a small chance that they contain 
unidentified material. There is a very small chance that such material may cause illness, including 
possibly serious illness. 
• 
There may be other side effects of the study vaccines that are not yet known. If new information 
about possible side effects of the study vaccines becomes available, we will let you know. 
• 
It is possible that the study vaccine virus could be spread from your child to other people in the 
home or daycare and may make them sick. It could be spread to young children and people with 
weakened immune systems. This is why children who will live with/share a daycare room with 
young babies during the 14 days after receiving the study vaccine or placebo or who live with 
people who have weak immune systems are not allowed to participate in the study. 
• 
The study vaccines could cause a severe allergic reaction. A severe reaction can cause hives, 
throat swelling, rapid heart rate, weakness, difficulty breathing, or death. These reactions are rare 
and have not been seen to date with the vaccines in this study. 
 
Risks of Nasal Swab 
Nasal swabs may cause brief discomfort and may rarely cause a nosebleed. 
 
Risks of Having Blood Drawn 
Blood drawing can cause bleeding, pain, bruising, or infection at the place where the blood is taken. 
Sometimes, blood drawing can cause your child to feel lightheaded or to faint. It sometimes takes more 
than one try to get blood from a small child. You may ask study staff about options for reducing the 
discomfort from drawing blood, such as numbing cream. 
WHY WOULD THE STUDY DOCTOR TAKE MY CHILD OFF OF THIS STUDY EARLY? 
The study doctors or the sponsor also have the right to end your child's participation in the study at any 
time without your consent for any of the following reasons: 
• 
For your child’s safety; 
• 
You do not follow study procedures as directed by the study doctors;  
• 
New information becomes available regarding the safety of the study vaccine; 
• 
If it is in your child's best interest; 
• 
You do not consent to continue in the study after being told of changes in the research that may 
affect your child; 
• 
The study sponsor, the International Maternal Pediatric Adolescent AIDS Clinical Trials Network 
(IMPAACT), the Advarra Institutional Review Board (IRB), the Office for Human Research 
Protections (OHRP), the National Institute of Allergy and Infectious Diseases (NIAID), or the 
United States Food and Drug Administration (FDA) decide to end the study. An IRB is a 
committee that watches over the safety and rights of research participants. 
 
WHAT HAPPENS IF MY CHILD IS INJURED? 
 
If your child suffers physical injury from this study, the study doctor will provide or will refer your child 
for appropriate medical treatment.  The study doctor will also provide referrals to appropriate health care 

 
  
 
IMPAACT 2021, FINAL Version 3.0 
Page 102 of 106 
28 April 2022 
facilities. The cost for this treatment will be charged to you or your insurance company.  There is no 
program for compensation either through this institution or the National Institutes of Health (NIH). No 
financial compensation by the doctors that gave your child the study vaccine or placebo will be made for 
any discomfort suffered because of participation in this study. You will not be giving up any of your 
child’s legal rights by signing and dating this consent form. 
ARE THERE BENEFITS TO TAKING PART IN THIS STUDY? 
• 
Your child may receive an active study vaccine that may reduce RSV disease; however, your 
child may not receive any direct benefit from being in the study. Other studies of these vaccines 
have shown an immune response, but they have not shown a reduced risk of disease so far. If 
your child receives placebo, your child will not receive protection against RSV. 
• 
Being in the study may help find a vaccine that works well to prevent serious RSV illness. Such a 
vaccine may be of future benefit to babies and children in this country and in the rest of the 
world. 
WHAT OTHER CHOICES DOES MY CHILD HAVE BESIDES THIS STUDY? 
There are no licensed vaccines to protect against RSV illness at this time. There is no other similar study 
or approved vaccine that we can offer your child. You may choose to not allow your child to take part in 
this study. 
WHAT ABOUT CONFIDENTIALITY? 
To help us protect your privacy, we have obtained a Certificate of Confidentiality from the National 
Institutes of Health. With this Certificate, the researchers cannot be forced to disclose information that 
may identify you, even by a court subpoena, in any federal, state, or local civil, criminal, administrative, 
legislative, or other proceedings. The researchers will use the Certificate to resist any demands for 
information that would identify you, except as explained below. The Certificate cannot be used to resist a 
demand for information from personnel of the United States Government that is used for auditing or 
evaluation of federally funded projects or for information that must be disclosed in order to meet the 
requirements of the federal Food and Drug Administration (FDA).   
 
You should understand that a Certificate of Confidentiality does not prevent you or a member of your 
family from voluntarily releasing information about you or your child’s participation in this research. If 
an insurer, employer, or other person obtains your written consent to receive research information, then 
the researchers may not use the Certificate of Confidentiality to withhold that information. 
 
The Certificate of Confidentiality does not prevent the researchers from disclosing voluntarily, without 
your consent, information that would identify you as a participant in the research project under certain 
circumstances such as child abuse.  
 
Your child’s name, birth date, and Social Security number are not routinely given to anyone unless required by 
law. All of the information you give us during this study will be put in locked file cabinets and/or in 
password-protected computer files. The only people who will have access to this information will be those 
who are involved in the study. 
 
There will be people involved in the study who need to see your child’s health information. These people 
may include the researchers, study and laboratory personnel, and other clinical research staff. Others who may 
see your child’s information are the groups of people who make sure that the study is being done as it 

 
  
 
IMPAACT 2021, FINAL Version 3.0 
Page 103 of 106 
28 April 2022 
should be: Advarra Institutional Review Board (IRB), the Center for Immunization Research (CIR), the 
National Institute of Allergy and Infectious Diseases (NIAID; NIH) Intramural Data and Safety 
Monitoring Board and others who need to see your child’s information to make sure that the study is going 
as planned.  
 
Other groups of people who may be involved in the study and may need to see your child’s 
information are: 
• 
The government agency “Office for Human Research Protections,” that makes sure that we are 
conducting the research as planned, and the US FDA, and the European Medicines Agency (EMA) 
• 
The sponsor of the study and people with whom the sponsor may contract for the study, such as 
study monitors. 
• 
Other US, local, and international regulatory groups 
 
At the end of the study, whatever we learn from the research may be used in a medical journal or used for 
teaching. Your child’s name or other details about his/her health will not be used in a manner such that 
anyone can personally identify your child. 
WHAT ARE THE COSTS TO ME? 
There are no costs to you or your child for him/her being in the study. The costs for the study 
vaccine/placebo, study visits, or study procedures are covered by the sponsor (NIH/NIAID). However, 
taking part in this study may lead to added costs to you or your child and your/your child’s insurance 
company if medical complications arise or if your child’s doctor decides extra tests are needed. In some 
cases, it is possible that your/your child’s insurance company will not pay for these costs, because your 
child is taking part in a research study.   
WILL MY CHILD RECEIVE ANY COMPENSATION? 
«Compensation» 
 
You will be paid up to a total of $xx.xx for your child's participation in this study at the following rate: 
 
• 
$xx.xx for Visits xxx.  
• 
$xx.xx for Visits xxx.  
• 
$xx.xx for Visits xxx.  
 
You will also be paid during the RSV surveillance period as follows: 
 
• 
$xx.xx for Visits xxx.  
• 
$xx.xx for Visits xxx.  
• 
$xx.xx for Visits xxx.  
 
If you stop your child from taking part in the study early, you will only be paid for the days of the study 
that your child completed. Your child may also receive age-appropriate books or small toys. If needed, 
bus tokens or parking passes may be given to you. 
 
If you have any questions regarding compensation for your child’s participation, please contact the study 
staff. 
 

 
  
 
IMPAACT 2021, FINAL Version 3.0 
Page 104 of 106 
28 April 2022 
You may be required to provide your Social Security number to be paid. If your payment for study 
participation exceeds $600 per year, this information must be reported to the Internal Revenue Service. 
WHAT ARE MY CHILD’S RIGHTS AS A RESEARCH PARTICIPANT? 
Taking part in this study is completely voluntary. You may choose not to have your child take part in this 
study or leave this study at any time. Your decision will not have any impact on your child’s participation 
in other studies and will not result in any penalty or loss of benefits to which you or your child are 
otherwise entitled. 
 
A study doctor, physician assistant, nurse practitioner, or study nurse will inform you of any significant 
abnormal physical findings and/or test results for your child and will make appropriate referrals back to 
your child’s primary care giver, if necessary. 
 
We will tell you about new information from this or other studies that may affect your child’s health, 
welfare, or willingness to stay in this study. You may be asked to sign and date a revised consent form if 
this occurs. If you want the results of the study, let the study staff know. 
 
At the end of the study, you will be told in writing whether your child was given one of the vaccines or 
the placebo. 
 
A description of this clinical trial will be available on http://www.ClinicalTrials.gov, as required by U.S. 
Law. This Web site will not include information that can identify your child. At most, the Web site will 
include a summary of the results. You can search this Web site at any time. 
WHAT ARE MY RESPONSIBILITIES? 
• 
If you decide to withdraw your child from the study early, we ask that you notify the study nurse 
or study doctor. 
• 
If your child comes off the study early, we will ask you to bring him/her into the clinic for an 
early discontinuation visit. At that visit, we will ask about your child’s health since the last visit 
and do a final blood draw (about 1 teaspoon) to measure antibodies (germ fighters) against RSV. 
• 
Any child who has received the study product will be encouraged to remain in the study so that 
safety information can be collected. 
• 
It is important that you do not enroll your child in other studies where your child receives the 
study vaccines or medications for 8 weeks after he/she receives vaccine/placebo. 
• 
If your child becomes ill, or this study site is closed due to COVID-19 safety concerns when a 
nasal swab should be collected, and you are comfortable collecting a nasal swab from him/her 
using supplies we give you, we may ask you to return the swab to the study team, or a study team 
member may come get the swab from you. You will receive instructions on how to collect, store, 
and return nasal swab samples and receive collection supplies during the visit when your child is 
enrolled and receives the study vaccine/placebo. 
WHOM TO CONTACT ABOUT THIS STUDY 
During the study, if your child experiences any medical problems or suffers a research-related injury or if 
you have questions, concerns, or complaints about the study, please contact the study doctor at the 
telephone number listed on the first page of this consent document. If you seek emergency care for your 
child, or hospitalization is required, alert the treating physician that your child is participating in this 
research study.  
 

 
  
 
IMPAACT 2021, FINAL Version 3.0 
Page 105 of 106 
28 April 2022 
An institutional review board (IRB) is an independent committee established to help protect the rights of 
research participants. If you have any questions about your child’s rights as a research participant and/or 
concerns or complaints regarding this research study, contact: 
 
• 
By mail: 
Study Subject Adviser 
Advarra IRB 
6100 Merriweather Dr., Suite 600 
Columbia, MD 21044 
• 
or call toll free:    877-992-4724 
• 
or by email:          adviser@advarra.com 
 
Please reference the following number when contacting the Study Subject Adviser: Pro000XXXXX. 
 
STORAGE AND FUTURE USE OF UNUSED SPECIMENS  
 
If you agree, any unused blood or nasal swab samples taken from your child will be stored indefinitely 
(with protectors of identity) once this study is complete. These unused blood and nasal swab samples will 
be stored as part of the Johns Hopkins University Center for Immunization Research’s approved 
biospecimen repository for vaccine research or at the Laboratory of Infectious Diseases at the National 
Institutes of Health. The samples may be used for future laboratory studies (including studies done by 
different investigators) to learn more about RSV and other viruses. These studies will be conducted 
without obtaining additional informed consent from you. The studies will not include human genetic 
research; that is, the study doctors will not look at your child’s genes (also known as DNA). 
 
• 
Your child’s unused blood or nasal swab samples, if any, will be used only for laboratory studies 
and will not be sold or used directly to make products that will be for sale. 
• 
The samples will not contain your child’s private information. They will be coded so that your 
child’s name cannot be easily identified. 
• 
Reports about studies done with your child’s unused samples will not be put in your child’s health 
or study records.  
• 
There will be no direct benefit to your child in using the samples as noted above, but from 
studying the unused samples of children taking part in the studies, we may learn more about the 
RSV germ or other viruses that cause illness in babies and children. 
• 
Results from future studies using your child’s unused samples may be included in medical papers 
and meeting reports, but your child’s name will not be used. 
 
You can change your mind at any time about allowing your child’s unused samples to be used for future 
laboratory studies. If you do change your mind, contact the study doctor or study nurse and let him/her 
know. Then the samples will no longer be used for laboratory studies and will be destroyed. 

 
  
 
IMPAACT 2021, FINAL Version 3.0 
Page 106 of 106 
28 April 2022 
PERMISSION FOR STORAGE AND FUTURE USE OF UNUSED SPECIMENS 
Your choice will not have any effect on your child’s taking part in this study. 
 
I will allow the use of my child’s unused blood or nasal swab samples to be stored indefinitely and to be 
used in future laboratory studies for the purposes described above. Your child’s name will not be 
available to the laboratory or to the scientists who may be doing any future tests. (Please check one and 
initial below) 
 
Yes:  
Initials _________ 
Date ____________ 
 
No:  
Initials _________ 
Date ____________ 
 
 
If NO, your child’s study samples will only be used for the testing described in this study.  
 
SIGNATURE AND DATE  
 
If you have read this consent form (or had it explained to you), all of your questions have been answered, 
and you agree your child can take part in this study, please sign and date your name below. 
 
 
____________________________                 
Study Participant’s Name (print) 
 
 
 
 
 
__________________________________ 
____________________________________ 
Participant’s Parent’s/Legal Guardian’s  
Parent’s/Legal Guardian’s Signature and Date 
 
 
Name (print) 
 
 
__________________________________ 
____________________________________ 
Study Staff Conducting  
 
 
Study Staff’s Signature and Date 
 
 
Consent Discussion’s Name (print)  
 
 
__________________________________ 
____________________________________ 
Witness’ Name (print)  
 
             Witness’ Signature and Date 
 
 
 
(As appropriate)