A Phase 4 Double-blind Study to Evaluate the Shedding and Immunogenicity of Trivalent and Quadrivalent Formulations of FluMist in Children 24 to < 48 Months of Age
Phase: PHASE4
Conditions: Influenza, Healthy
Sponsor: MedImmune LLC

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A Phase 4 Double-blind Study to Evaluate the Shedding 
and Immunogenicity of Trivalent and Quadrivalent 
Formulations of FluMist in Children 24 to < 48 Months of 
Age
Sponsor Protocol Number: D2560C00013
Application Number:
Investigational Product:
Quadrivalent live attenuated influenza vaccine (Q/LAIV)
Sponsor:
MedImmune, LLC, a wholly owned subsidiary of AstraZeneca
One MedImmune Way
Gaithersburg, MD 20878, USA
Medical Monitor:
Contract Research Organization:
Protocol History, Date: Original Protocol, 03Mar2017
Amendment 1, 02Jun2017
 

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TABLE OF CONTENTS
PROTOCOL SYNOPSIS..........................................................................................................6
LIST OF ABBREVIATIONS .................................................................................................10
1
INTRODUCTION ........................................................................................................11
1.1
Disease Background...........................................................................................11
1.2
FluMist Quadrivalent (MEDI3250) Background...............................................11
1.3
Summary of Nonclinical Experience .................................................................12
1.4
Summary of Clinical Experience .......................................................................13
1.5
Rationale for Conducting the Study...................................................................14
1.6
Benefit-Risk and Ethical Assessment ................................................................14
1.7
Research Hypotheses..........................................................................................16
2
OBJECTIVES AND ENDPOINTS..............................................................................16
2.1
Objectives...........................................................................................................16
2.1.1Primary Objective ......................................................................................16
2.1.2Secondary Objectives.................................................................................17
2.1.3Exploratory Objectives...............................................................................17
2.2
Study Endpoints .................................................................................................17
2.2.1Primary Endpoint .......................................................................................17
2.2.2Secondary Endpoints..................................................................................17
2.2.3Exploratory Endpoints................................................................................18
3
STUDY DESIGN .........................................................................................................18
3.1
Description of the Study.....................................................................................18
3.1.1Treatment Regimen....................................................................................20
3.2
Rationale for Dose, Population, and Endpoints .................................................20
3.2.1Dose Rationale ...........................................................................................20
3.2.2Rationale for Study Population ..................................................................20
3.2.3Rationale for Endpoints..............................................................................20
4
MATERIALS AND METHODS..................................................................................21
4.1
Subjects ..............................................................................................................21
4.1.1Number of Subjects....................................................................................21
4.1.2Inclusion Criteria........................................................................................21
4.1.3Exclusion Criteria.......................................................................................21
4.1.4Subject Enrollment and Randomization.....................................................22
4.1.5Withdrawal from the Study........................................................................23
4.1.6Discontinuation of Investigational Product................................................23
4.1.7Replacement of Subjects............................................................................23
4.1.8Withdrawal of Informed Consent for Data and Biological Samples .........24

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4.2
Schedule of Study Procedures............................................................................25
4.2.1Screening Visit (Visit 1 [Days -75 to 1]) ...................................................30
4.2.2Treatment Period, Dose 1 (Visit 2 [Day 1])...............................................30
4.2.3Follow-up Period, After Dose 1 (Visits 3 to 7 [Days 2, 3, 4, 5, 7])...........30
4.2.4Telephone Contact Follow-up After Dose 1 (Days 15 [+2], 21 [+2])........31
4.2.5Treatment Period, Dose 2 (Visit 8 [Day 28 (+2)]).....................................31
4.2.6Follow-up Period, After Dose 2 (Visits 9 to 11 [Days 30 (+2), 32 (+2), 
34 (+2)]) ...................................................................................31
4.2.7Telephone Contact Follow-up After Dose 2 (Days 42 [+2], 48 [+2])........32
4.2.8Final Visit (Visit 12 [Day 56 +/- 2]) ..........................................................32
4.2.9Optional Study Visit...................................................................................32
4.3
Description of Study Procedures........................................................................33
4.3.1Medical History and Physical Examination...............................................33
4.3.2Clinical Laboratory Tests...........................................................................33
4.3.3Serum Immunogenicity Evaluation and Methods......................................33
4.3.4Shedding Evaluation and Methods.............................................................33
4.3.5Nasal HA-Specific IgA Evaluation and Methods ......................................34
4.3.6Estimate of Volume of Blood to Be Collected...........................................34
4.4
Study Suspension or Termination ......................................................................34
4.5
Investigational Products.....................................................................................35
4.5.1Identity of Investigational Product(s).........................................................35
4.5.1.1
Investigational Product Handling.............................................36
4.5.1.2
Investigational Product Inspection...........................................37
4.5.1.3
Treatment Administration ........................................................37
4.5.1.4
Monitoring of Dose Administration.........................................37
4.5.1.5
Reporting Product Complaints.................................................37
4.5.2Additional Study Medications....................................................................38
4.5.3Labeling………..........................................................................................38
4.5.4Storage………............................................................................................38
4.5.5Treatment Compliance ...............................................................................38
4.5.6Accountability............................................................................................38
4.6
Treatment Assignment and Blinding..................................................................39
4.6.1Methods for Assigning Treatment Groups.................................................39
4.6.2Methods to Ensure Blinding.......................................................................39
4.6.3Methods for Unblinding.............................................................................40
4.6.3.1
Unblinding in the Event of a Medical Emergency...................40
4.6.3.2
Unblinding for Planned Analysis Purposes..............................40

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4.7
Restrictions During the Study and Concomitant Treatment(s) ..........................40
4.7.1Permitted Concomitant Medications..........................................................40
4.7.2Prohibited Concomitant Medications.........................................................41
4.8
Statistical Evaluation..........................................................................................41
4.8.1General Considerations ..............................................................................41
4.8.2Sample Size................................................................................................42
4.8.3Analyses of Immunogenicity and Shedding…….......................................43
4.8.3.1
Primary Endpoint Analysis ......................................................43
4.8.3.2
Secondary Endpoint Analyses..................................................43
4.8.3.3
Exploratory Endpoint Analyses................................................44
4.8.3.4
Subgroup Analyses...................................................................44
4.8.4Safety………..............................................................................................44
4.8.5Interim Analysis .........................................................................................44
5
ASSESSMENT OF SAFETY.......................................................................................45
5.1
Definition of Adverse Events.............................................................................45
5.2
Definition of Serious Adverse Events................................................................45
5.3
Recording of Adverse Events.............................................................................46
5.3.1Time Period for Collection of Adverse Events ..........................................46
5.3.2Follow-up of Unresolved Adverse Events .................................................46
5.3.3Deaths……….............................................................................................47
5.4
Reporting of Serious Adverse Events ................................................................47
5.5
Other Events Requiring Immediate Reporting...................................................48
5.5.1Overdose……….........................................................................................48
5.6
Solicited Symptoms............................................................................................48
6
STUDY AND DATA MANAGEMENT .....................................................................49
6.1
Training of Study Site Personnel .......................................................................49
6.2
Monitoring of the Study.....................................................................................49
6.2.1Source Data ................................................................................................50
6.2.2Study Agreements ......................................................................................50
6.2.3Archiving of Study Documents..................................................................50
6.3
Study Timetable and End of Study ....................................................................50
6.4
Data Management ..............................................................................................50
6.5
Medical Monitor Coverage ................................................................................51
7
ETHICAL AND REGULATORY REQUIREMENTS................................................51
7.1
Subject Data Protection......................................................................................51
7.2
Ethics and Regulatory Review ...........................................................................52
7.3
Informed Consent...............................................................................................52

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7.4
Changes to the Protocol and Informed Consent Form.......................................53
7.5
Audits and Inspections .......................................................................................53
8
REFERENCES .............................................................................................................54
9
CHANGES TO THE PROTOCOL ..............................................................................55
9.1
Protocol Amendment 1.......................................................................................55
10
APPENDICES ..............................................................................................................56
10.1
Appendix 10.1 – Signature of Principal Investigator.........................................56
10.2
Appendix 10.2 - Additional Safety Guidance ....................................................58
10.3
Appendix 10.3 - National Institute of Allergy and Infectious Disease and 
Food Allergy and Anaphylaxis Network Guidance for Anaphylaxis 
Diagnosis ................................................................................................62
10.4
Appendix 10.4 – 2016-2017 FluMist Quadrivalent Package Insert...................63
LIST OF IN-TEXT TABLES
Table 4.2-1
Schedule of Study Procedures.............................................................26
Table 4.5.1-1
Identification of Investigational Products ...........................................35
Table 4.8.2-1
Power Calculations..............................................................................42
LIST OF IN-TEXT FIGURES
Figure 3.1-1
Study Flow Diagram ...........................................................................19

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PROTOCOL SYNOPSIS
TITLE
A Phase 4 Double-blind Study to Evaluate the Shedding and Immunogenicity of Trivalent and Quadrivalent 
Formulations of FluMist in Children 24 to < 48 Months of Age 
HYPOTHESES  
No formal hypotheses will be tested in this study; detailed descriptive statistics will be provided for all 
endpoints. This includes descriptions of shedding characteristics, immune responses, and safety. Potential 
relationships among these measures will be explored.
OBJECTIVES
Primary objective: 
To describe the level of serum hemagglutination inhibition (HAI) antibody responses induced by trivalent and 
quadrivalent formulations of FluMist against antigenically matched influenza strains.
Secondary objectives:
1.
To describe the proportion of individuals who shed vaccine viruses
2.
To describe the duration of shedding of vaccine viruses
3.
To quantify the titer of shed vaccine viruses
4.
To describe the level of serum neutralizing antibody responses induced by trivalent and quadrivalent 
formulations of FluMist against antigenically matched influenza strains
5.
To describe the level of mucosal antibody responses induced by trivalent and quadrivalent formulations of 
FluMist against antigenically matched influenza strains.
6.
To describe the safety and tolerability of trivalent and quadrivalent formulations of FluMist.
Exploratory objectives:
1.
To further characterize the serum and mucosal immune responses following vaccination
2.
To compare results of shedding analyses using culture-based methods and quantitative real-time polymerase 
chain reaction (qRT-PCR).
STUDY ENDPOINTS
Primary endpoints:
•
The proportion of subjects with strain-specific HAI seroconversion rates (≥ 4-fold increase) from baseline 
through Days 28 and 56 by treatment group.
Secondary endpoints:
•
The proportion of subjects who shed vaccine by formulation, strain, dose number, and baseline serostatus 
(by qRT-PCR)
•
The number of days of shedding by formulation, strain, dose number, and baseline serostatus (by qRT-
PCR)
•
Viral titer by day, strain, dose number and baseline serostatus (by qRT-PCR)
•
The proportion of subjects with strain-specific neutralizing antibody seroconversion rates (≥ 4-fold 
increase) from baseline through Days 28 and 56, by baseline serostatus
•
The proportion of subjects with strain-specific nasal immunoglobulin A (IgA) increase (≥ 2-fold increase) 
from baseline through Days 28 and 56
•
The proportion of subjects with any strain-specific antibody response defined as a ≥ 4-fold increase in HAI 
antibodies or a ≥ 4-fold increase neutralizing antibodies or ≥ 2-fold increase in IgA antibodies
•
The proportion of subjects with solicited symptoms experienced from administration of investigational 
product through 14 days post last vaccination
•
The proportion of subjects with treatment-emergent adverse events (AEs) experienced from administration 
of investigational product through 28 days post last vaccination

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•
The proportion of subjects with treatment-emergent serious adverse events (SAEs) experienced from 
administration of investigational product through 28 days post last vaccination.
Exploratory endpoints:
•
Endpoints to be determined based on specific assays to characterize immune responses
•
The proportion of subjects who shed vaccine by formulation, strain, dose number, and baseline serostatus 
(by culture-based methods)
•
The number of days of shedding by formulation, strain, dose number, and baseline serostatus  (by culture-
based methods)
•
Viral titer by day, strain, dose number, and baseline serostatus (by culture-based methods).
STUDY DESIGN  
This randomized, double-blind, multi-center study will enroll approximately 200 children 24 to < 48 months of 
age, at screening. Subjects will be randomized (~65 subjects per group) at 1:1:1 ratio to receive two doses of 
either 1) a quadrivalent formulation of FluMist®. Strains included in the vaccine will be based on the World 
Health Organization (WHO) and Vaccines and Related Biological Products Advisory Committee (VRBPAC)
2017-2018 Northern Hemisphere recommendations and will include a replacement H1N1 strain 
(A/Slovenia/2903/2015) and A/New Caledonia/7/2014(H3N2), B/Phuket/3073/2013 (B/Yamagata-lineage), and 
B/Brisbane/60/2008 (B/Victoria-lineage); 2) a second quadrivalent formulation of FluMist. Strains included in 
the vaccine will be based on the 2015-2016 licensed formulation of FluMist: A/Bolivia/559/2013 (H1N1), 
A/Switzerland/9715293/2013 (H3N2), B/Phuket/3073/2013 (B/Yamagata-lineage), and B/Brisbane/60/2008 
(B/Victoria-lineage); or 3) a trivalent formulation of FluMist. Strains included in the vaccine will be based on 
the strains recommended by the WHO and VRBPAC for the 2015-2016 season: A/Bolivia/559/2013 (H1N1), 
A/Switzerland/9715293/2013 (H3N2), and B/Phuket/3073/2013 (B/Yamagata-lineage).
Subjects will be screened for the study within 75 days prior to randomization. Randomization will be stratified 
according to whether the subject ever received prior influenza vaccination (Yes/No). It is intended that 
approximately 50% of randomized subjects will not have been previously vaccinated. All subjects will receive 
an initial dose of investigational product at the site on Study Day 1. Subjects will receive a second dose on 
Study Day 28.
Nasal samples for evaluation of shedding will be obtained from each subject on Days 2, 3, 4, 5, and 7 after Dose 
1 and on Days 2, 4 and 6 after Dose 2. Blood and nasal samples for the assessment of immune responses will be 
obtained on Day 1 prior to dosing, on Day 28 (prior to dosing) and on Day 56.
Safety evaluation will consist of the collection of solicited symptoms during the 14-day period after each dose, 
and AEs, SAEs, and concomitant medication use through the 28-day period post each dose. On Days 1 and 28, 
subjects’ legal representatives will be given a temperature log to record daily temperature during the 14 days 
post dosing. Four telephone contacts for safety follow-up will occur between Days 15-16, Days 21-23, Days 42-
44 and 48-50. 
The study will be conducted during the influenza “off-season” in the US. It is anticipated that enrollment will 
start around the beginning of June 2017. The duration of subject participation is approximately 3 to 4 months. 
After completion of the study all subjects will be offered and strongly encouraged to receive one or two doses 
(depending on their vaccination history) of an inactivated influenza vaccine approved for use in the US for the 
2017-2018 influenza season.
TARGET SUBJECT POPULATION  
Male and female children 24 months to < 48 months of age, at screening.
TREATMENT GROUPS AND REGIMENS  
Subjects will be randomly assigned in a 1:1:1 ratio to receive a single dose on Study Days 1 and 28 of either 
FluMist Quadrivalent 2017-2018 formulation (approximately 65 subjects), FluMist Quadrivalent 2015-2016 
formulation (approximately 65 subjects), or FluMist trivalent 2015-2016 formulation (approximately 
65 subjects) by intranasal spray.

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STATISTICAL METHODS
Sample size:  
HAI Immunogenicity:
It is expected that for each analysis of immunogenicity, 90% of subjects will be evaluable. The resulting sample 
size of ~60 evaluable subjects per arm would produce a 95% confidence interval (CI) within 14 percentage 
points of the observed proportion of subjects seroconverting. An estimate of 40% for the proportion of subjects 
seroconverting was used for the purposes of CI calculations.
Assuming that the seroconversion rate in the A/Bolivia H1N1 strain (2015-2016 formulation) ranged from 10% 
to 40%, based on 25% of the rate difference, the sample size of 60 evaluable subjects per arm would result in 
approximately 80% power to detect a statistically significant difference in the seroconversion rate comparing the 
A/Bolivia H1N1 strain (2015-2016 formulation) to the replacement H1N1 strain selected for the 2017-2018 
vaccine formulation (A/Slovenia/2903/2015). The table below summarizes the study power based on various 
assumptions.
Power Calculations
Percentage of Subjects with Immune 
Response
Absolute 
Difference (%)
N Per Group
Power (%)
A/Bolivia Strain
A/Slovenia Strain
10
25
15
60
58
30
20
60
78
35
25
60
91
40
30
60
97
50
40
60
99
20
35
15
60
45
40
20
60
67
45
25
60
84
50
30
60
94
30
30
45
60
39
50
20
60
61
55
25
60
79
60
30
60
92
40
55
15
60
37
60
20
60
59
65
25
60
79
70
30
60
92
Shedding:
It is expected that for each analysis of shedding, 90% of subjects will be evaluable. The resulting sample size of 
~60 evaluable subjects per arm would produce a 95% CI within 15 percentage points of the observed proportion 
of subjects who shed. An estimate of 50% for the proportion of subjects shedding influenza vaccine virus was 
used for the purposes of sample size calculations, as this value was statistically conservative (ie, had the highest 
variability).
Statistical analyses:
Primary endpoint analysis:
The primary endpoint is the strain-specific HAI antibody seroconversion rates, defined as at least 4-fold increase 
from baseline through Day 28 and Day 56. The proportion of subjects who had seroconversion will be 
summarized at Days 28 and 56 visits by strain and treatment. Its corresponding 95% exact CI will be provided.   
The difference in proportion between the A/Bolivia H1N1 strain (2015-2016) and the replacement H1N1 strain 

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selected for the 2017-2018 vaccine formulation will be tested by Cochran–Mantel–Haenszel (CMH) test 
adjusting for the prior flu vaccination status. If the number of subjects in any stratum is too small, Fisher’s exact 
test will be used without adjusting for the prior flu vaccination status. If it is evident that the proportion is 
confounded with some of other demographic and baseline disease characteristic variables, the confounding 
variables will be adjusted.
Secondary endpoint analyses:
Geometric mean titers (GMTs) and geometric mean fold rises (GMFRs) of HAI antibody, neutralizing antibody, 
and nasal IgA will be summarized by strain and treatment at Days 28 and 56 visits. Corresponding 95% CI will 
be calculated assuming log normal distribution. 
Using the results of the qRT-PCR method, the proportion of subjects who shed vaccine will be summarized by 
treatment, strain, and dose number based on the same method as for the primary analysis. The number of days of 
shedding will be summarized descriptively by treatment, strain, dose number, and baseline serostatus. The viral 
titer will be calculated by day, strain, dose number, and baseline serostatus. 
The strain-specific neutralizing antibody seroconversion rates (≥ 4-fold increase from baseline), and 
strain-specific nasal IgA increase (≥ 2-fold increase from baseline) at Days 28 and 56 visits will be summarized 
descriptively using the same method as for the primary endpoint.
Exploratory endpoint analyses:
Analyses of immune response will be conducted based on newly identified specific assays to characterize 
immune response.
Using the results of culture-based methods, the proportion of subjects who shed vaccine, the number of days of 
shedding, and the viral titer will be summarized using the same methods as described for secondary endpoint 
analyses.
Subgroup analyses:
Subgroup analysis by baseline serostatus and prior vaccination status will be conducted for primary and 
secondary endpoints.

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LIST OF ABBREVIATIONS
Abbreviation or 
Specialized Term
Definition
ACIP
Advisory Committee on Immunization Practices
AE
adverse event
att
attenuated
BD
Becton Dickinson (Accuspray™)
ca
cold adapted
CDC
Centers for Disease Control and Prevention
CI
confidence interval
eCRF
electronic case report form
EDC
electronic data capture
FFU
fluorescent focus unit
GCP
Good Clinical Practice
GMP
Good Manufacturing Practice
HAI 
hemagglutination inhibition
ICF
informed consent form
ICH
International Council for Harmonisation
IEC
Independent Ethics Committee
IRB
Institutional Review Board
ITT
intent-to-treat
IWRS
interactive web response system
qRT-PCR
quantitative real-time polymerase chain reaction
SAE
serious adverse event
SID
subject identification
TIV
trivalent inactivated vaccine
ts
temperature sensitive
US FDA
United States Food and Drug Administration
USA
United States of America
VRBPAC
Vaccines and Related Biological Products Advisory Committee
WHO 
World Health Organization

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1
INTRODUCTION
1.1
Disease Background
Influenza is a highly contagious, acute febrile illness of global importance. It is the most 
common vaccine-preventable disease in the developed world. In humans, influenza illness is 
caused mainly by 2 types of viruses: influenza A, with multiple subtypes categorized by 
hemagglutinin and neuraminidase surface antigens, and influenza B, which circulates as 
2 major antigenic lineages (Yamagata and Victoria). A/H3N2 and A/H1N1 are 
the 2 influenza A subtypes that have circulated and caused human disease since 1977 
(Kilbourne, 2006).
Uncomplicated influenza illness in healthy individuals is generally a self-limited febrile 
respiratory disease of 3 to 7 days’ duration, sometimes with persistence of cough and malaise 
for several weeks. Influenza illness is characterized by the abrupt onset of signs and 
symptoms such as fever, myalgia, headache, malaise, chills, nonproductive cough, anorexia, 
sore throat, and rhinitis. Children may also have otitis media, croup, nausea, and vomiting. 
Complications of influenza include primary influenza viral pneumonia; exacerbation of 
underlying medical conditions such as cardiac or pulmonary disease, including asthma or 
chronic obstructive pulmonary disease; and secondary bacterial infections such as 
pneumonia, sinusitis, or otitis. Young children can have febrile seizures or symptoms 
mimicking bacterial sepsis with high fevers. Rarely, influenza virus infection has been 
associated with encephalopathy, transverse myelitis, myositis, rhabdomyolysis, myocarditis, 
pericarditis, and, in children, Reye syndrome (Fiore et al, 2007; Ramet et al, 2007).
1.2
FluMist Quadrivalent (MEDI3250) Background
FluMist® Quadrivalent is an intranasally administered influenza vaccine that was developed 
as a successor to the trivalent seasonal vaccine, FluMist (also referred to as trivalent live 
attenuated influenza vaccine [T/LAIV]). Refer to the current package insert for additional 
details (Appendix 10.4). 
The active agents of FluMist Quadrivalent consist of 2 cold adapted (ca), 
temperature-sensitive (ts), attenuated (att) reassortant influenza strains of type A (ie, A/H1N1 
and A/H3N2), 1 ca/ts/att reassortant influenza strain of type B-Victoria, and 1 ca/ts/att
reassortant influenza strain of type B-Yamagata. The types A and B master donor viruses 
(MDVs), from which the reassortant strains are derived, were adapted to grow in primary 
chick kidney cells at 25°C by sequential passage at progressively lower temperatures. During 

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the process of cold adaptation, each virus acquired mutations that conferred unique biological 
phenotypes of cold adaptation, temperature sensitivity, and attenuation, which distinguish 
these viruses from wild-type influenza viruses.
While the commercial formulation of FluMist Quadrivalent can be stored at 2°C to 8°C, the 
vaccine to be used in this study will require storage in a freezer.
1.3
Summary of Nonclinical Experience
A number of nonclinical studies of FluMist have been conducted in ferrets, as the ferret has 
been proven to be a good model for studying influenza. 
Primary pharmacodynamic studies in ferrets have been conducted to evaluate the replication 
and immunogenicity of live attenuated influenza vaccine strains. Results of replication, 
immunogenicity, and challenge studies in ferrets demonstrated that vaccination with trivalent 
FluMist protected animals following challenge with wild-type virus; vaccine-induced 
immunity in these animals substantially decreased replication of the wild-type virus in the 
lungs as well as the upper airways. Studies with FluMist Quadrivalent demonstrated that it 
was equally immunogenic, had similar replication kinetics, and conferred equally efficient 
protection following challenge with wild-type viruses.
A single- and repeat-dose toxicology study was conducted in ferrets to investigate the 
potential adverse effects of trivalent FluMist given 1 or 3 times to ferrets over a 15-week 
period. The regimen consisted of up to 3 human doses of trivalent FluMist administered 
intranasally at Weeks 0, 4, and 14. This dosing regimen is in compliance with International 
Council for Harmonisation (ICH) Guideline M3, which recommends a toxicity study duration 
of 3 months with a product dosing duration of up to 1 month. No clinical indications of 
toxicity were manifest during the course of the study from any of the parameters evaluated. 
No test material-related toxicity was identified in the major organs examined 
histopathologically, except for increased incidence of acute, multifocal, suppurative 
inflammation of the nasal turbinates, and lymph node hyperplasia in animals at interim 
necropsy. These findings were most likely due to inoculation 3 days prior to necropsy and the 
antigenic responses of the animals to the inoculum. Overall, in this study and a similar repeat-
dose study conducted with FluMist Quadrivalent in ferrets, the vaccine was well tolerated.
Studies with trivalent FluMist were conducted to evaluate reproductive and developmental 
toxicology in 2 different animal models (rat and ferret). Results of the study conducted with 
rats indicated that exposure to trivalent FluMist once prior to mating and once during 

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pregnancy did not produce any maternal toxicity or affect the reproductive capacity of the 
dam. These exposures did not produce embryo-fetal toxicity in near-term fetuses or pups 
evaluated for 21 days postpartum. Results of a similar study in which quadrivalent FluMist 
was administered 3 times prior to mating and again 3 times during gestation showed no safety 
concerns.
The study in ferrets involved intranasal administration of trivalent FluMist to pregnant ferrets 
at 4 different time points during gestation. No vaccine treatment-related effects were 
observed with respect to maternal mortality, clinical observations, or body weight during 
gestation, nor were there any treatment-related effects observed in fetal parameters or in 
maternal macroscopic pathology that could be attributed to the intranasal instillation of 
trivalent FluMist. 
The potential for ocular toxicity resulting from the inadvertent instillation of trivalent FluMist 
into the eye was evaluated in 2 ocular toxicity studies in rabbits using a standard Draize test. 
Neither study elicited results consistent with ocular toxicity.
The results of the nonclinical studies performed with trivalent FluMist and FluMist 
Quadrivalent collectively demonstrate that the vaccine has a favorable safety and tolerability
profile.
1.4
Summary of Clinical Experience
In over 60 clinical studies, more than 120,000 subjects from 6 weeks to > 90 years of age 
have been administered MedImmune’s egg-produced vaccine, FluMist. These studies were 
designed to evaluate the safety, efficacy, and immunogenicity of the vaccine among various 
study populations, including > 90,000 children and adolescents 6 weeks to 17 years of age 
and > 30,000 adults 18 to > 90 years of age. In these studies, FluMist was found to be 
generally safe and well tolerated. In healthy adults 18 through 64 years of age, FluMist 
recipients reported higher rates of runny nose (44%) and sore throat (26%) than placebo 
recipients (27% and 17%, respectively), with a median event duration of 1 day regardless of 
treatment received. Other symptoms, including cough, headache, chills, muscle aches, and 
tiredness/weakness occurred less often and at similar rates between the treatment groups. 
Low-grade fever (temperature > 100ºF) occurred at a similarly low rate for FluMist and 
placebo recipients (1.3% and 1.5%, respectively).
The clinical development of FluMist Quadrivalent included 2 pivotal, double-blind studies 
conducted in the USA, one in children and adolescents 2 to 17 years of age (MI-CP208; 

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2,312 subjects) and one in adults 18 through 49 years of age (MI-CP185; 1,800 subjects), 
both of which demonstrated that the immune responses generated by FluMist Quadrivalent 
were noninferior to the immune responses generated by FluMist and the safety and 
tolerability profiles of the 2 vaccines were similar in both populations. 
In addition to the clinical study experience, over 200,000 doses of FluMist have been 
administered in post-marketing studies, and more than
 doses of FluMist have 
been distributed commercially worldwide from initial licensure in 2003. FluMist was initially 
approved for use in healthy individuals 5 to 49 years of age; however, the age indication was 
expanded to include children 24 to 59 months of age prior to the 2007-2008 influenza season. 
For this study population, there are no risks anticipated other than those described in the 
Package Insert (Appendix 4).
The 2016-2017 FluMist Quadrivalent Package Insert (Appendix 9.4) provides the most 
current safety data and product use information.
1.5
Rationale for Conducting the Study
In light of concerns regarding the low effectiveness of FluMist Quadrivalent against influenza 
A(H1N1)pdm09 strains in the United States during the 2013–2014 and 2015–2016 influenza 
seasons, the US Advisory Committee on Immunization Practices (ACIP) issued an interim 
recommendation on June 22, 2016 that FluMist Quadrivalent should not be used in the US for 
the 2016-2017 influenza season (Grohskopf et al, 2016). The vaccine remains licensed for 
use by the US FDA as the agency considers that “the benefits of FluMist Quadrivalent 
outweigh any potential risks.” (US FDA, 2016). This study is being conducted to describe the 
immunogenicity, safety, and viral shedding of a new A/H1N1 strain (A/Slovenia/2903/2015) 
that will be incorporated into the FluMist Quadrivalent for the 2017-2018 influenza season to 
the immunogenicity, safety, and viral shedding of the previous A/H1N1 strain 
(A/Bolivia/559/2013) that was included in the vaccine in the 2015-2016 and 2016-2017 
influenza seasons. The results from this study will be included as part of a larger submission 
of data to the ACIP as they consider whether to re-issue a recommendation for use of FluMist 
Quadrivalent in the US.
1.6
Benefit-Risk and Ethical Assessment
The study will be performed in accordance with ethical principles that have their origin in the 
Declaration of Helsinki and are consistent with ICH/Good Clinical Practice, and applicable 
regulatory requirements.

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Considerations relating to benefits:
In placebo-controlled studies with greater than 13,000 pediatric subjects conducted during 
7 influenza seasons from 1996 through 2003 in Europe, Latin America, Africa, Asia/Oceania, 
and the US, trivalent FluMist protection against laboratory-confirmed influenza illness was 
demonstrated in a broad age range of children. In these placebo controlled studies, trivalent 
FluMist consistently demonstrated high rates of efficacy against culture-confirmed influenza 
caused by wild-type virus strains antigenically matched to those in the vaccine (ranging from 
62.2% to 100%) and also against all strains regardless of antigenic match. In 3 trivalent 
inactivated vaccine (TIV)-controlled studies involving > 12,000 children, the vaccine 
consistently demonstrated statistically significant superior efficacy relative to TIV against 
culture-confirmed influenza illness caused by wild-type virus strains antigenically matched to 
those in the vaccine as well as against illness caused by all strains regardless of antigenic 
match. Compared to TIV, trivalent FluMist reduced the number of cases of culture-confirmed 
influenza illness by 35% to 53% for illness due to matched strains and by 32% to 55% for 
illness due to all strains regardless of antigenic match. 
Since incorporation of 2009 H1N1pdm09 strains into the vaccine, however, the effectiveness 
of the vaccine against this influenza subtype has been less clear. While the vaccine has 
demonstrated effectiveness against H3N2 and B strains, effectiveness against H1N1 strains 
has varied by country and by influenza season. Based on a study from the Centers for Disease 
Control and Prevention (CDC), the vaccine appeared effective against H1N1 when given as a 
monovalent vaccine in 2009-2010. However, based on a retrospective evaluation of the CDC 
data for 2010-2011 season, the trivalent vaccine did not appear to have been effective against 
H1N1 strains in the US. For the 2013-2014 season, the quadrivalent vaccine was not effective 
for H1N1 strains in the US in studies performed by both the CDC and MedImmune, but the 
trivalent formulation does appear to have been effective in Canada, based on both a test-
negative study and a cluster-randomized trial. Based on the findings from both 2010-2011 
and 2013-2014 seasons, MedImmune replaced the H1N1 component of the vaccine 
(A/California/07/2009) with a more heat stable strain (A/Bolivia/559/2013). Replacement of 
the A/California strain may have improved the effectiveness of the vaccine, however, the 
effectiveness of the vaccine against A/H1N1pdm09 strains was still lower than expected 
during the 2015-2016 influenza season, and MedImmune plans to replace this strain with a 
new H1N1 strain (A/Slovenia/2903/2015) for the 2017-2018 season.

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Study participants will be offered and encouraged to take an optional dose of a licensed 
inactivated influenza vaccine at the end of the study in order to maximize the likelihood that 
they are protected against influenza.
Considerations relating to risks:
There are two important identified risks for FluMist, wheezing in children under the age of 
2 years and hypersensitivity (including anaphylaxis). Data from clinical studies found vaccine 
recipients < 24 months of age in both TIV and trivalent FluMist study treatment groups had 
higher rates of medically significant wheezing than vaccine recipients ≥ 24 months of age. In 
one study, FluMist recipients < 24 months of age had increased rates of medically significant 
wheezing compared to TIV recipients. For vaccine recipients ≥ 24 months of age, no 
statistically significant increases were observed between treatment groups in medically 
significant wheezing, with the point estimates generally being higher for TIV compared to 
trivalent FluMist. FluMist is not indicated for children under the age of 2 years. 
Hypersensitivity reactions can occur with all vaccines and typically occur in genetically 
predisposed individuals. The likelihood of a hypersensitivity reaction to FluMist may be 
decreased by not giving the product to patients with known allergies to components of the 
product. In addition to the important potential risks, the most common clinical trial solicited 
adverse reactions (≥10% in FluMist recipients and at least 5% greater than in placebo 
recipients) were runny nose or nasal congestion (ages 2 years through 49 years), fever over 
100°F (children ages 2 years through 6 years), and sore throat (adults ages 18 years through 
49 years). 
1.7
Research Hypotheses
No formal hypotheses will be tested in this study; detailed descriptive statistics will be 
provided for all endpoints. This includes descriptions of shedding characteristics, immune 
responses, and safety. Potential relationships among these measures will be explored.
2
OBJECTIVES AND ENDPOINTS
2.1
Objectives
2.1.1
Primary Objective
To describe the level of serum hemagglutination inhibition (HAI) antibody responses induced 
by trivalent and quadrivalent formulations of FluMist against antigenically matched influenza 
strains

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2.1.2
Secondary Objectives
1. To describe the proportion of individuals who shed vaccine viruses
2. To describe the duration of shedding of vaccine viruses
3. To quantify the titer of shed vaccine viruses
4. To describe the level of serum neutralizing antibody responses induced by trivalent and 
quadrivalent formulations of FluMist against antigenically matched influenza strains
5. To describe the level of mucosal antibody responses induced by trivalent and quadrivalent 
formulations of FluMist against antigenically matched influenza strains
6. To describe the safety and tolerability of trivalent and quadrivalent formulations of 
FluMist
2.1.3
Exploratory Objectives
1. To further characterize the serum and mucosal immune responses following vaccination
2. To compare results of shedding analyses using culture-based methods and quantitative 
real-time polymerase chain reaction (qRT-PCR)
2.2
Study Endpoints
2.2.1
Primary Endpoint
The proportion of subjects with strain-specific HAI seroconversion rates (≥ 4-fold increase) 
from baseline through Days 28 and 56 by treatment group.
2.2.2
Secondary Endpoints
1. The proportion of subjects who shed vaccine by formulation, strain, dose number, and 
baseline serostatus (by quantitative real-time polymerase chain reaction [qRT-PCR])
2. The number of days of shedding by formulation, strain, dose number, and baseline 
serostatus (by qRT-PCR)
3. Viral titer by day, strain, dose number, and baseline serostatus (by qRT-PCR)
4. The proportion of subjects with strain-specific neutralizing antibody seroconversion rates 
(≥ 4-fold increase) from baseline through Days 28 and 56, by baseline serostatus
5. The proportion of subjects with strain-specific nasal Immunoglobulin A (IgA) increase 
(≥2-fold increase) from baseline through Days 28 and 56
6. The proportion of subjects with any strain-specific antibody response defined as a ≥ 4-
fold increase in HAI antibodies or a ≥ 4-fold increase neutralizing antibodies or ≥ 2-fold 
increase in IgA antibodies
7. The proportion of subjects with solicited symptoms experienced from administration of 
investigational product through 14 days post last vaccination

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8. The proportion of subjects with treatment-emergent adverse events (AEs) experienced 
from administration of investigational product through 28 days post last vaccination
9. The proportion of subjects with treatment-emergent serious adverse events (SAEs)
experienced from administration of investigational product through 28 days post last 
vaccination.
2.2.3
Exploratory Endpoints
1. Endpoints to be determined based on specific assays to characterize immune responses
2. The proportion of subjects who shed vaccine by formulation, strain, dose number, and 
baseline serostatus (by culture-based methods)
3. The number of days of shedding by formulation, strain, dose number, and baseline 
serostatus (by culture-based methods)
4. Viral titer by day, strain, dose number, and baseline serostatus (by culture-based 
methods).
3
STUDY DESIGN
3.1
Description of the Study
This randomized, double-blind, multi-center study will enroll approximately 200 children 24 
to < 48 months of age, at screening. Subjects will be randomized (~65 subjects per group) at 
1:1:1 ratio to receive two doses of either 1) a quadrivalent formulation of FluMist. Strains 
included in the vaccine will be based on the WHO and VRBPAC 2017-2018 Northern 
Hemisphere recommendations and will include a replacement H1N1 strain
(A/Slovenia/2903/2015) and A/New Caledonia/71/2014 (H3N2), B/Phuket/3073/2013 
(B/Yamagata-lineage), and B/Brisbane/60/2008 (B/Victoria-lineage); 2) a second 
quadrivalent formulation of FluMist. Strains included in the vaccine will be based on the 
2015-2016 licensed formulation of FluMist: A/Bolivia/559/2013 (H1N1),
A/Switzerland/9715293/2013 (H3N2), B/Phuket/3073/2013 (B/Yamagata-lineage), and 
B/Brisbane/60/2008 (B/Victoria-lineage); or 3) a trivalent formulation of FluMist. Strains 
included in the trivalent vaccine will be based on the strains recommended by the WHO and 
VRBPAC for the 2015-2016 season: A/Bolivia/559/2013 (H1N1), 
A/Switzerland/9715293/2013 (H3N2), and B/Phuket/3073/2013 (B/Yamagata-lineage).
Subjects will be screened for the study within 75 days prior to randomization. Randomization 
will be stratified according to whether the subject ever received prior influenza vaccination 
(Yes/No). It is intended that approximately 50% of randomized subjects will not have been 
previously vaccinated. All subjects will receive an initial dose of investigational product at 
the site on Study Day 1. Subjects will receive a second dose on Study Day 28.

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Nasal samples for evaluation of shedding will be obtained from each subject on Days 2, 3, 4, 
5, and 7 after Dose 1 and on Days 2, 4, and 6 after Dose 2. Blood and nasal samples for the 
assessment of immune responses will be obtained on Day 1 prior to dosing, on Day 28 (prior 
to dosing) and on Day 56.
Safety evaluation will consist of the collection of solicited symptoms during the 14-day 
period after each dose, and AEs, SAEs, and concomitant medication use through the 28-day 
period post each dose. On Days 1 and 28, subjects’ legal representatives will be given a 
temperature log to record daily temperature during the 14 days post dosing. Four telephone 
contacts for safety follow-up will occur between Days 15-16, Days 21-23, Days 42-44 and 
Days 48-50. 
The study will be conducted during the influenza “off-season” in the US. It is anticipated that 
enrollment will start around the beginning of June 2017. The duration of subject participation 
is approximately 3 to 4 months. After completion of the study all subjects will be offered and 
strongly encouraged to receive one or two doses (depending on their vaccination history) of 
an inactivated influenza vaccine approved for use in the US for the 2017-2018 influenza 
season.
Figure 3.1-1
Study Flow Diagram
Q/LAIV = quadrivalent live attenuated influenza vaccine; T/LAIV = trivalent live attenuated influenza vaccine
The endpoints to be measured in this study are described in Section 2.2.

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3.1.1
Treatment Regimen
Subjects will be randomly assigned in a 1:1:1 ratio to receive a single dose on Study Days 1 
and 28 of either FluMist Quadrivalent 2017-2018 formulation (approximately 65 subjects), 
FluMist Quadrivalent 2015-2016 formulation (approximately 65 subjects), or FluMist 
trivalent 2015-2016 formulation (approximately 65 subjects) by intranasal spray.
3.2
Rationale for Dose, Population, and Endpoints
3.2.1
Dose Rationale
Subjects enrolled in the study will receive two 0.2-mL doses of vaccine (0.1 mL per nostril) 
with the second dose administered approximately 4 weeks after the first dose. Each 0.2-mL 
dose will contain 107±0.5 fluorescent focus units (FFU) of each vaccine strain. The dose 
volume and dose level are based on the United States Food and drug Administration (US 
FDA) approved indication for FluMist Quadrivalent. In order to fully characterize the 
immunogenicity and shedding of the vaccine strains, all subjects will receive two doses.
3.2.2
Rationale for Study Population
The study population of young children was selected as this age group has been shown to 
have the highest level of immune responses to live attenuated influenza vaccines 
(Coelingh et al, 2015) and to shed vaccine viruses at high titers (Mallory et al, 2011). As a 
result, this population will allow for comparisons of the immunogenicity and viral shedding 
of the new A/H1N1 strain (A/Slovenia/2903/2015) that will be incorporated into the FluMist 
Quadrivalent vaccine for the 2017-2018 influenza season to the immunogenicity and viral 
shedding of the previous A/H1N1 strain (A/Bolivia/559/2013) that was included in the 
vaccine in the 2015-2016 and 2016-2017 influenza seasons.
3.2.3
Rationale for Endpoints
Hemagglutination inhibition antibodies and neutralizing antibodies are induced by influenza 
vaccination and are standard assays recommended by Regulatory Authorities to evaluate the 
immunogenicity of different vaccine formulations (Committee for Medicinal Products for 
Human Use [CHMP], 2016). Additionally, for intranasally administered live attenuated 
vaccines, mucosal IgA responses have been associated with protective efficacy against 
influenza infection (Ambrose et al, 2012). The ability to successfully replicate in the 
nasopharynx is an important characteristic of live attenuated vaccines and is associated with 
the induction of immune responses. The extent and duration of replication can be assessed 

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through the serial collection of nasal samples in which the titer of vaccine virus can be 
quantified.
In combination, solicited symptoms, adverse events, and serious adverse events provide a 
clinically meaningful summary of both the safety and tolerability profile of FluMist vaccine 
formulations. Use of these endpoints, which have been widely used in previous FluMist 
studies, will also allow the safety data collected in this study to be compared to that collected 
in previous studies.
4
MATERIALS AND METHODS
4.1
Subjects
4.1.1
Number of Subjects
Approximately 200 subjects are planned for participation in the study.
4.1.2
Inclusion Criteria
Subjects must meet all of the following criteria:
1. Age 24 months to < 48 months of age at the time of screening.
2. Written informed consent and any locally required authorization (eg, data privacy) 
obtained from the legal representative prior to performing any protocol-related 
procedures, including screening evaluations.
3. Healthy by medical history and physical examination or presence of stable underlying 
chronic medical condition for which hospitalization has not been required in the previous 
year.
4. Child’s legal representative able to be contacted by telephone throughout the study 
duration.
5. Child’s legal representative is able to understand and comply with the requirements of the 
protocol, as judged by the investigator.
4.1.3
Exclusion Criteria
Any of the following would exclude the subject from participation in the study:
1. History of allergic disease or reactions likely to be exacerbated by any component of the 
investigational product; 
2. Acute illness or evidence of significant active infection (including fever ≥ 100.4°F 
[38.0°C]) at randomization; 
3. History of asthma or history of recurrent wheezing;

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4. Any drug therapy from 15 days prior to randomization or expected drug therapy through 
28 days post last dose with the exception of chronic medications that have been well 
tolerated and were not initiated and/or did not have a dosage change within 90 days prior 
to randomization; 
5. Any known immunosuppressive condition or immune deficiency disease; Note: topical 
corticosteroids for uncomplicated dermatitis may be used throughout the study according 
to the judgment of the investigator; topical calcineurin inhibitors may be used in 
accordance with their package insert at entry and during study participation
6. Current or expected receipt of immunosuppressive medications within a 28-day window 
around vaccination; 
7. Use of aspirin or salicylate-containing medications within 28 days prior to randomization 
or expected receipt through 28 days after vaccination; 
8. Use of antiviral agents with activity against influenza viruses within 48 hours prior to first 
dose of investigational product or anticipated use of such agents through the end of the 
study follow-up period;
9. Receipt of any nonstudy seasonal influenza vaccine within 90 days of Dose 1 or planned 
receipt of nonstudy seasonal influenza vaccine prior to 28 days after last vaccination;
10. Receipt of immunoglobulin or blood products within 90 days before randomization into 
the study or expected receipt during study participation;
11. Administration of intranasal medications within 10 days prior to randomization, or 
expected receipt through 10 days after administration of each dose of investigational 
product;
12. Any investigational agent from 28 days prior to randomization through the end of the 
study follow-up period;
13. Known or suspected mitochondrial encephalomyopathy;
14. History of Guillain-Barré syndrome.
Note: an individual who initially is excluded from study participation based on one or more 
of the above time-limited criteria may be reconsidered for enrollment once the condition has 
resolved as long as the subject continues to meet all other entry criteria and the same subject 
identification (SID) number is used.
4.1.4
Subject Enrollment and Randomization
Study participation begins (ie, a subject is “enrolled”) once written informed consent is 
obtained. Once informed consent is obtained, a subject identification (SID) number will be 
assigned by a central system (an interactive web response system, IWRS) and the screening 
evaluations may begin to assess study eligibility (inclusion/exclusion) criteria. The SID 
number will be used to identify the subject during the screening process and throughout study 
participation, if applicable. 

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A master log of all consented subjects will be maintained at the site and will document all 
screening failures (ie, subjects who are consented but do not meet study eligibility criteria 
and/or are not randomized), including the reason(s) for screening failure.
Subjects who fail to meet the inclusion/exclusion criteria (ie, screening failures) should not be 
randomized or receive investigational product. Randomization will be stratified according to 
whether the subject received prior influenza vaccination (Yes/No). It is intended that 
approximately 50% of subjects randomized will not have been previously vaccinated.
4.1.5
Withdrawal from the Study
Subjects are free to withdraw their consent to participate in the study (investigational product 
and assessments) at any time, without prejudice to further treatment (withdrawal of consent). 
The subject’s legal representative will be asked about the reason(s) and the presence of any 
adverse events (AEs). If possible, the subject will be seen and assessed by the investigator. 
Adverse events will be followed up; diary assessment worksheets should be returned by the 
subject’s legal representative. If a subject withdraws from further participation in the study, 
then no further study visits or data collection should take place.
4.1.6
Discontinuation of Investigational Product
An individual subject will not receive any further investigational product if any of the 
following occur in the subject in question:
1. Withdrawal of consent from further treatment with investigational product 
2. Lost to follow-up
3. An adverse event (AE) that, in the opinion of the investigator or the sponsor, warrants 
discontinuation of further dosing or meets criteria for discontinuation from investigational 
product
4. Subject is determined to have met one or more of the exclusion criteria or failed to meet 
all of the inclusion criteria for study participation
Subjects who are permanently discontinued from receiving investigational product will be 
followed for protocol-specified assessments including follow-up of any AEs unless consent is 
withdrawn from further study participation (Section 4.1.5), the subject is lost to follow-up, or 
the subject is enrolled in another clinical study.
4.1.7
Replacement of Subjects
Subjects will not be replaced.

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4.1.8
Withdrawal of Informed Consent for Data and Biological Samples
Biological Samples Obtained for the Main Study
Study data are protected by the use of an SID number, which is a number specific to the 
subject. The investigator is in control of the information that is needed to connect a study 
sample to a subject. A subject’s consent to the use of data does not have a specific expiration 
date, but the subject’s legal representative may withdraw consent at any time by notifying the 
investigator. If consent is withdrawn, any samples collected prior to that time may still be 
given to and used by the sponsor but no new data or samples will be collected unless 
specifically required to monitor safety of the subject.
Samples Obtained for Future Research
Samples obtained for future research will be labeled with a sample identification number 
linked to the SID number but will not be labeled with personal identifiers such as the 
subject’s name. If the subject’s legal representative withdraws consent for participating in the 
future research, the sponsor will locate the subject’s sample and destroy it. The coding of 
samples and results is to ensure that these research results are kept confidential by keeping 
the subject’s identity and these results separate.
If the subject’s legal representative consents to have his/her samples used for future research, 
this additional research may not start immediately and may start at any time during the 
storage period. The subject’s sample(s) will be stored by the sponsor with similar samples 
from other subjects at a secure central laboratory. The subject’s samples will not be kept for 
more than 15 years after the end of the study in which they were collected. If the subject’s 
legal representative chooses not to allow the study samples to be used for future research, the 
samples will be destroyed by the sponsor once they are no longer required for the main study.
If consent is withdrawn after a sample has been taken but before the subject’s sample is sent 
to the sponsor for future research, the investigator will arrange to have it destroyed. If consent 
is withdrawn after the subject’s sample(s) have been sent to the sponsor for future research, 
the sponsor and the investigator will ensure that these sample(s) are destroyed unless the 
sample identification number has been removed and the subject can no longer be linked to 
any sample(s). However, if the subject’s samples have already been used for research, the 
sponsor is not required to destroy results of this research. In this case only the remaining 
sample(s) will be destroyed.

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4.2
Schedule of Study Procedures
Table 4.2-1 shows all procedures to be conducted at the screening, treatment, and follow-up 
visits. Assessments should be performed in the order shown in the table.
Whenever vital signs and blood draws are scheduled for the same nominal time, the blood 
draws should occur last. 

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Table 4.2-1
Schedule of Study Procedures
Visit (V) or 
Telephone 
Contact 
(TC)
V1
V2
V3
V4
V5
V6
V7
TC
V8
V9 
V10
V11
TC
V12
Study 
Period
Scr
Dose 1
Post Dose 1
Dose 2
Post Dose 2
Study Day
-75
to 1
1
2
3
4
5
7
15 
(+2)
21 
(+2)
28 (+2)
30 (+2)
32 (+2)
34 (+2)
42 (+2)
48 (+2)
56 (± 2)
Written 
informed 
consent/
assignment 
of SID 
number
X
Verify 
eligibility 
criteria
X
X
X
Medical 
history at 
screening
X
Medical 
history
update
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Concom-
itant 
medications
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Physical 
examina-
tion 
including 
weight, 
height, and 
vital signs
X
X 
X 

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Table 4.2-1
Schedule of Study Procedures
Visit (V) or 
Telephone 
Contact 
(TC)
V1
V2
V3
V4
V5
V6
V7
TC
V8
V9 
V10
V11
TC
V12
Study 
Period
Scr
Dose 1
Post Dose 1
Dose 2
Post Dose 2
Study Day
-75
to 1
1
2
3
4
5
7
15 
(+2)
21 
(+2)
28 (+2)
30 (+2)
32 (+2)
34 (+2)
42 (+2)
48 (+2)
56 (± 2)
Targeted 
physical 
examina-
tionb
X
X
X
X
X
X
X
X
X
Assessment 
of 
AEs/SAEs
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Randomize, 
assign 
investiga-
tional 
product via 
IWRS
X
X d
Administer 
investiga-
tional 
product
X
X
Observe at 
least 15 min 
post 
investiga-
tional 
product 
administra-
tion
X
X

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Table 4.2-1
Schedule of Study Procedures
Visit (V) or 
Telephone 
Contact 
(TC)
V1
V2
V3
V4
V5
V6
V7
TC
V8
V9 
V10
V11
TC
V12
Study 
Period
Scr
Dose 1
Post Dose 1
Dose 2
Post Dose 2
Study Day
-75
to 1
1
2
3
4
5
7
15 
(+2)
21 
(+2)
28 (+2)
30 (+2)
32 (+2)
34 (+2)
42 (+2)
48 (+2)
56 (± 2)
Collect 
nasal 
samples for 
shedding 
X
X
X
X
X
X
X
X
Collect 
nasal 
samples for 
immune 
response 
Xa
Xa
X
Collect 
blood for 
assessment 
of immune 
responses
Xa
Xa
X
Provide 
thermom-
eters and 
diary 
assessment 
worksheet 
X
Xc
Collect and 
review diary 
assessment 
worksheet
Xe
Xe
Xe
Xe
Xe
Xe
Xe
Xf
Xe
Xe
Xe
Xe
Xe
Xf
Collect 
solicited 
X
X
X
X
X
X
X
X
X
X

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Table 4.2-1
Schedule of Study Procedures
Visit (V) or 
Telephone 
Contact 
(TC)
V1
V2
V3
V4
V5
V6
V7
TC
V8
V9 
V10
V11
TC
V12
Study 
Period
Scr
Dose 1
Post Dose 1
Dose 2
Post Dose 2
Study Day
-75
to 1
1
2
3
4
5
7
15 
(+2)
21 
(+2)
28 (+2)
30 (+2)
32 (+2)
34 (+2)
42 (+2)
48 (+2)
56 (± 2)
symptoms
AEs = adverse events; IWRS = interactive web response system; SAEs = serious adverse events; Scr = screen; SID = subject identification
a
Collect prior to dosing.
b
Targeted physical examination, if appropriate. 
c
Only provide thermometer if replacement is needed.
d
Contact IWRS for assignment of investigational product kit number and sprayer number only, randomization not needed. 
e
Review diary assessment worksheet only.
f
Collect diary assessment worksheet on Day 28 (± 2) for Days 1-15 and on Day 56 (± 2) for Days 28-42.

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4.2.1
Screening Visit (Visit 1 [Days -75 to 1])
All screening procedures must be performed within 75 days before or on the same day as 
investigational product administration (Day -75 to Day 1). The screening evaluations may be 
carried out over more than one visit. Written informed consent and any locally required 
privacy act document authorization must be obtained prior to performing any protocol-
specific procedures, including screening evaluations.
1. Obtain written informed consent and appropriate privacy act document authorization 
2. Assign an SID number
3. Verify eligibility criteria
4. Obtain screening medical history
5. Record concomitant medication use
6. Perform screening physical examination, including vital signs, height, and weight
7. Assess for AEs/SAEs.
4.2.2
Treatment Period, Dose 1 (Visit 2 [Day 1])
1. Verify eligibility criteria.
2. Review medical history, concomitant medication use (any new findings since screening), 
and perform physical examination (including height, weight, and temperature)
3. Assess for AEs/SAEs.
4. Randomize and assign investigational product kit number via IWRS..
5. Obtain nasal samples for immune responses prior to dosing. 
6. Obtain blood for immune responses prior to dosing. 
7. Administer investigational product.
8. Observe subject for a minimum of 15 minutes. Provide diary assessment workbook, 
thermometer, and instructions for completing the workbook. Ensure that the subject’s 
legal representative understands how to take subject’s temperature. Day 1 temperature is 
recorded by the subject’s legal representative during the evening of Day 1 (day of 
investigational product administration). The diary assessment workbook will be used for 
the collection of body temperature and solicited symptoms and will be completed by the 
subject’s legal representative to serve as a memory aid for future data collection by study 
staff during visits and telephone contacts. Diary assessment workbooks will be returned 
to the site at the study Day 28 visit.
9. Assess for post dose AEs/SAEs.
4.2.3
Follow-up Period, After Dose 1 (Visits 3 to 7 [Days 2, 3, 4, 5, 7])
1. Update medical history, perform targeted physical examination if appropriate
2. Assess for AEs/SAEs
3. Update concomitant medications

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4. Collect nasal samples for shedding evaluation
5. Review diary assessment and solicited symptoms.
4.2.4
Telephone Contact Follow-up After Dose 1 (Days 15 [+2], 21 [+2])
1. Update medical history
2. Assess AEs/SAEs
3. Update concomitant medications
4. Review diary assessment workbook information for all 14 days (at Day 15 [+2] telephone 
call).
4.2.5
Treatment Period, Dose 2 (Visit 8 [Day 28 (+2)])
1. Update medical history, perform physical examination including vital signs (see Section 
4.3.1 for specifics) before administration of investigational product.
2. Assess AEs/ SAEs and concomitant medication use
3. Collect diary assessment workbooks for Days 1-14 (post Dose 1)
4. Verify ongoing eligibility (Section 4.1) before administration of investigational product
5. Obtain nasal sample for evaluation of immune response before administering Dose 2 
6. Obtain blood for evaluation of immune response before administering Dose 2 
7. Contact IWRS for assignment of investigational product kit number and sprayer number
8. Provide diary assessment workbook and instructions for completion. Ensure that the 
subject’s legal representative understands how to contact the site to report AEs and how 
to take temperatures and fill out the diary assessment workbook. A thermometer is only 
provided if replacement is needed. The diary assessment workbook will be used for the 
collection of body temperature and solicited symptoms and will be completed by the 
subject’s legal representative to serve as a memory aid for future data collection by study 
staff during visits and telephone contacts. Diary assessment workbooks will be returned 
to the site at the last subject visit (Day 56 ± 2). 
9. Administer investigational product
10. Observe at least 15 minutes post investigational product administration
11. Assess for post dose AEs/SAEs.
4.2.6
Follow-up Period, After Dose 2 (Visits 9 to 11 [Days 30 (+2), 32 (+2), 34
(+2)])
1. Update medical history, perform targeted physical examination if appropriate
2. Assess for AEs/SAEs 
3. Update concomitant medications
4. Collect nasal samples for shedding evaluation 
5. Review diary assessment and solicited symptoms.

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4.2.7
Telephone Contact Follow-up After Dose 2 (Days 42 [+2], 48 [+2])
1)
Update medical history
2)
Assess AEs/SAEs
3)
Update concomitant medications
4)
Review diary assessment workbook information for all 14 days (at Day 42 [+2]
telephone call).
4.2.8
Final Visit (Visit 12 [Day 56 +/- 2])
1)
Update medical history, perform targeted physical examination if appropriate
2)
Assess AEs/SAEs 
3)
Update concomitant medications
4)
Collect diary assessment workbooks for Days 28-42
5)
Obtain nasal sample for evaluation of immune response 
6)
Obtain blood for evaluation of immune response.
4.2.9
Optional Study Visit
Subjects will be offered and encouraged to receive commercial inactivated influenza vaccine 
as approved for the upcoming influenza season unless receipt is felt to be contraindicated 
according to the judgment of the investigator. The commercial inactivated influenza vaccine 
will be administered in accordance with the package insert. The optional dose(s) of influenza 
vaccine should be administered prior to the start of the influenza season. The optional study 
dose(s) must occur at least 28 days after Dose 2 has been administered. Dosing will be 
scheduled based on the availability of commercial inactivated influenza vaccine, the onset of 
influenza activity in the area, and at the convenience of the subject/legal representative and 
the site. 
As with any vaccine, allergic reactions after administration are possible. Therefore, 
appropriate drugs and medical equipment to treat acute anaphylactic reactions must be 
immediately available, and study personnel must be trained to recognize and treat 
anaphylaxis. After vaccination, all participants will be observed for a minimum of 
15 minutes by the study staff. Emergency management supplies (eg, AMBU bag, adrenaline 
[epinephrine], antihistamine) must be available for initial treatment of an allergic reaction if 
needed.  
If subjects experience AEs following receipt of an optional dose of commercial influenza 
vaccine, the investigator will be advised to report them as required per local spontaneous 
postmarketing pharmacovigilance procedures. If the event is an SAE that has occurred within 

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the study duration, it should also be reported in accordance with Section 5.4 Reporting of 
SAEs.
4.3
Description of Study Procedures
4.3.1
Medical History and Physical Examination 
Medical history by body system and physical examination, including vital signs (temperature 
[any route], heart rate, and respiratory rate), height and weight in appropriate units will be 
completed during screening and on Days 1 and 28, prior to dosing.
4.3.2
Clinical Laboratory Tests
No clinical laboratory tests will be performed.
4.3.3
Serum Immunogenicity Evaluation and Methods
Subjects will have 3 blood samples collected for serum influenza HAI antibody testing,
serum influenza neutralizing antibody testing, and potentially other anti-influenza serology 
tests: one on Day 1 prior to receipt of investigational product, one on Day 28 (+ 2 days) prior 
to receiving Dose 2 of investigational product, and one on Day 56 (± 2 days; see time points 
Table 4.2-1). Serum will be separated and stored frozen at -20 ± 5°C or below until being 
batched and shipped to the central laboratory according to procedures specified in the 
Laboratory Manual. Serum can also be stored at -60°C or below.
Immune response evaluation will consist of serum HAI antibody titers and serum 
neutralizing antibody titers, both measurements to strains antigenically matched to those 
contained in the quadrivalent or trivalent vaccine formulation received. Additional assays 
may be performed to investigate immune responses to influenza or other respiratory viruses. 
Samples may also be retained for potential future testing for immune response to influenza if
the subject’s legal representative has given consent to potential future testing (no human 
genetic testing will be performed). Immunogenicity assays will be conducted following 
standard influenza HAI antibody and microneutralization assay procedures.
4.3.4
Shedding Evaluation and Methods
Instructions for obtaining and processing nasopharyngeal swab samples are provided in the 
Laboratory Manual. Nasopharyngeal swabs for quantification of influenza viral shedding will 
be obtained on Days 2, 3, 4, 5, 7, 30, 32, and 34 (see time points Table 4.2-1). All 
nasopharyngeal samples obtained from vaccinated subjects will have virus shedding 
quantified by qRT-PCR. Strain-specific qRT-PCR primer sets will be used to differentially 

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quantitate shedding of individual strains. A subset of the collected samples may also have 
influenza virus quantified by next generation sequencing.
4.3.5
Nasal HA-Specific IgA Evaluation and Methods
Quantification of influenza vaccine strain specific anti-HA IgA will be performed by 
collecting nasal fluid samples on Day 1 prior to receipt of investigational product, Day 28 
(+ 2 days) prior to receiving Dose 2 of investigational product, and on Day 56 (± 2 days; see 
time points Table 4.2-1). Instructions for collecting and processing the nasal fluid samples 
are provided in the Laboratory Manual. Anti-HA-specific IgA quantification will be 
performed using an anti-HA serology assay to quantitate antibodies to the different H1, H3 
and B-specific hemagglutinins.
4.3.6
Estimate of Volume of Blood to Be Collected
A maximum total of approximately 15 mL of blood will be collected over the course of this 
study: 5 mL for each of the 3 immunogenicity blood samples.
4.4
Study Suspension or Termination
The sponsor reserves the right to temporarily suspend or permanently terminate this study at 
any time. The reasons for temporarily suspending or permanently terminating the study may 
include but are not limited to the following: 
1. The incidence or severity of AEs in this or other studies indicates a potential health 
hazard to subjects
2. Subject enrollment is unsatisfactory
3. Noncompliance that might significantly jeopardize the validity or integrity of the study
4. Sponsor decision to terminate the study
If MedImmune determines that temporary suspension or permanent termination of the study 
is required, MedImmune will discuss the reasons for taking such action with all participating 
investigators (or head of the medical institution, where applicable). When feasible, 
MedImmune will provide advance notice to all participating investigators (or head of the 
medical institution, where applicable) of the impending action.
If the study is suspended or terminated for safety reasons, MedImmune will promptly inform 
all investigators, heads of the medical institutions (where applicable), and/or institutions 
conducting the study. MedImmune will also promptly inform the relevant regulatory 
authorities of the suspension/termination along with the reasons for such action. Where 
required by applicable regulations, the investigator or head of the medical institution must 

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inform the Institutional Review Board (IRB)/Independent Ethics Committee (IEC) promptly 
and provide the reason(s) for the suspension/termination. If the study is suspended for safety 
reasons and it is deemed appropriate by the sponsor to resume the study, approval from the 
relevant regulatory authorities (and IRBs/IECs when applicable) will be obtained prior to 
resuming the study.
4.5
Investigational Products
4.5.1
Identity of Investigational Product(s)
MedImmune will provide the investigator(s) with investigational product (Table 4.5.1-1) 
using designated distribution centers. 
Table 4.5.1-1
Identification of Investigational Products 
Investigational Product
Manufacturer
Concentration and Formulation as 
Supplied
FluMist Quadrivalent
2017-2018 formulation
MedImmune
107.0 ± 0.5 FFU of each of 4 ca, att, ts, 6:2 
reassortant influenza strains per 0.2 mL in the 
BD Accuspray device:
•
A/H1N1 (Slovenia/2903/2015)
•
A/H3N2 (A/New Caledonia/71/2014)
•
B (B/ Phuket/3073/2013)
•
B (B/Brisbane/60/2008)
 
 
FluMist Quadrivalent
2015-2016 formulation
MedImmune
107.0 ± 0.5 FFU of each of 4 ca, att, ts, 6:2 
reassortant influenza strains per 0.2 mL in the 
BD Accuspray device:
•
A/H1N1 (A/Bolivia/559/2013)
•
A/H3N2 (A/Switzerland/9715293/2013)
•
B (B/Phuket/3073/2013)
•
B (B/Brisbane/60/2008)
 
 

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Table 4.5.1-1
Identification of Investigational Products 
Investigational Product
Manufacturer
Concentration and Formulation as 
Supplied
FluMist trivalent
2015-2016 formulation
MedImmune
107.0 ± 0.5 FFU of each of 3 ca, att, ts, 6:2 
reassortant influenza strains per 0.2 mL in the 
BD Accuspray device:
•
A/H1N1 (A/Bolivia/559/2013)
•
A/H3N2 (A/Switzerland/9715293/2013)
•
B (B/Phuket/3073/2013)
 
 
att = attenuated; BD = Becton Dickinson; ca = cold adapted; FFU = fluorescent focus unit; ts = temperature 
sensitive; w/v = weight per volume
Investigational product will be packaged and stored at -30°C and shipped to the study site 
upon request of the sponsor or designee. The distributor will ship the investigational product 
directly to the clinical study site by express courier. Receiving departments should be 
notified that rapid handling of the shipment is required. Upon receipt at each study site, 
frozen investigational product should be immediately transferred to a -20°C (or -4°F) freezer 
(variations up to ± 5°C are acceptable) in a secure location with limited access. 
Investigational product will be supplied to the site in devices with identical appearances in 
coded kits. Each kit has a unique number that is printed on all labels within the kit (ie, the 
outer carton label and the label of each device within the carton). Each sprayer is also labeled 
with a unique number. Labels will be prepared in accordance with Good Manufacturing 
Practice (GMP) and local regulatory guidelines. 
4.5.1.1
Investigational Product Handling
Investigational product should not be removed from storage until the day of dosing. Remove 
only the sprayer to be administered; other sprayers in the kit must remain in the labeled 
storage conditions and must not thaw. Any broken or damaged sprayer must be identified as 
damaged and the sprayer number recorded on the investigational product accountability 
record. Damaged sprayers can be stored at room temperature until accountability is 
completed.

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4.5.1.2
Investigational Product Inspection
At room temperature, investigational product is a colorless to pale yellow liquid, and clear to 
slightly cloudy. Some proteinaceous particles may be present but they do not affect the use of 
the product. If there are any defects noted with the investigational product, the investigator 
and site monitor should be notified immediately.  Refer to the Product Complaint section for 
further instructions.
4.5.1.3
Treatment Administration
The first day of dosing is considered Day 1.
•
Investigational product should be brought to room temperature by holding the sprayer in 
the palm of the hand and supporting the plunger rod with the thumb (see Appendix 10.4). 
The investigational product should be administered immediately thereafter.
•
A single administration comprises intranasal delivery of approximately 0.2 mL total 
volume (0.1 mL into each nostril). Each sprayer has a divider that allows delivery of 
approximately half the contents of the sprayer into one nostril. Removal of the divider 
allows delivery of the remaining volume into the other nostril.
•
The individual administering the investigational product should depress the plunger rod 
as rapidly as possible to generate a fine mist. Half of the contents of each sprayer will be 
sprayed as a fine mist into each nostril while the subject is in an upright position.
•
After administration, used study sprayers must be placed immediately after use into 
locked containers or sealed bags.
4.5.1.4
Monitoring of Dose Administration
As with any vaccine, allergic reactions to dose administration are possible. Therefore, 
appropriate drugs and medical equipment to treat acute anaphylactic reactions must be 
immediately available, and study personnel must be trained to recognize and treat 
anaphylaxis. After vaccination, all subjects will be observed for a minimum of 15 minutes by 
the study staff. Emergency management supplies (eg, AMBU bag, adrenaline [epinephrine], 
antihistamine) will be made available for the initial treatment of an allergic reaction if 
needed. Local reactions or systemic events must be recorded.
4.5.1.5
Reporting Product Complaints
Any defects with the investigational product must be reported immediately to the 
MedImmune Product Complaint Department by the site with further notification to the site 
monitor. All defects will be communicated to MedImmune and investigated further with the 
Product Complaint Department. During the investigation of the product complaint, all 
investigational product must be stored at labeled conditions unless otherwise instructed.

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MedImmune contact information for reporting product complaints:
Email: productcomplaints@medimmune.com
4.5.2
Additional Study Medications
No other study medications are specified for use in this clinical protocol.
4.5.3
Labeling……….
Labels for the investigational product will be prepared in accordance with Good 
Manufacturing Practice (GMP) and local regulatory guidelines. Label text will be translated 
into local languages, as required.
4.5.4
Storage……….
Investigational product must be stored in the original outer package and must not be thawed. 
The manufacturer’s instructions for shipment and storage will be followed at all times. It is 
the responsibility of the investigator to maintain daily temperature logs for the freezer, at a 
minimum, daily Monday through Friday. The investigator will be provided with temperature 
monitors that record minimum/maximum temperatures, unless temperature monitors are 
already in place.
4.5.5
Treatment Compliance
Investigational product is administered by study site personnel, who will monitor 
compliance.
4.5.6
Accountability
The investigator’s or site’s designated investigational product manager is required to 
maintain accurate investigational product accountability records. Upon completion of the 

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study, copies of investigational product accountability records will be returned to 
MedImmune. All unused investigational product will be returned to a 
MedImmune-authorized depot or disposed of upon authorization by MedImmune.
4.6
Treatment Assignment and Blinding
4.6.1
Methods for Assigning Treatment Groups
An IWRS will be used for randomization to a treatment group and assignment of blinded
investigational product kit and sprayer numbers. A subject is considered randomized into the 
study when the investigator notifies the IWRS that the subject meets eligibility criteria and 
the IWRS provides the assignment of blinded investigational product to the subject.
Subjects will be randomized using a 1:1:1 ratio to receive either FluMist Quadrivalent
2017-2018 formulation, FluMist Quadrivalent 2015-2016 formulation, or FluMist trivalent 
2015-2016 formulation. Investigational product (FluMist Quadrivalent 2017-2018 
formulation, FluMist Quadrivalent 2015-2016 formulation, or FluMist trivalent 2015-2016 
formulation) must be administered the same day the investigational product is assigned. If 
there is a delay in the administration of investigational product such that it will not be 
administered within the specified timeframe, the study monitor must be notified immediately.
Subjects will receive a second dose of the same vaccine 28 days after the first dose. An 
IWRS will be used for assignment of the blinded investigational product kit number. Subjects 
are assigned the blinded investigational product kit number after the investigator notifies 
IWRS that the subject meets eligibility criteria for receipt of Dose 2. 
4.6.2
Methods to Ensure Blinding
This is a double-blind study in which FluMist Quadrivalent 2017-2018 formulation, FluMist 
Quadrivalent 2015-2016 formulation, and FluMist trivalent 2015-2016 formulation are 
identically labeled and indistinguishable in appearance. As such, neither the subject/legal 
representative nor any of the investigator or sponsor staff who are involved in the treatment 
or clinical evaluation of the subjects will be aware of the treatment received (ICH E9). In the 
event that treatment allocation for a subject becomes known to the investigator or other study 
staff involved in the management of study subjects, the sponsor must be notified 
immediately. 

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4.6.3
Methods for Unblinding
4.6.3.1
Unblinding in the Event of a Medical Emergency 
In the event of a medical emergency, the investigator may unblind an individual subject’s 
investigational product allocation. Instructions for unblinding an individual subject’s 
investigational product allocation are contained in the IWRS manual. In general, unblinding 
should only occur if management of the medical emergency would be different based on the 
subject having received investigational product. In the majority of cases, the management of 
a medical emergency would be the same whether or not investigational product was received 
by the subject. If this was the case, the investigational product allocation should not be 
unblinded.
MedImmune retains the right to unblind the treatment allocation for serious adverse events 
(SAEs) that are unexpected and are suspected to be causally related to an investigational 
product and that potentially require expedited reporting to regulatory authorities. 
4.6.3.2
Unblinding for Planned Analysis Purposes 
Planned analyses are described in Section 4.8. The study will be fully unblinded at the time 
of its completion.
4.7
Restrictions During the Study and Concomitant Treatment(s)
The investigator must be informed as soon as possible about any medication taken from the 
time of screening until the end of the clinical phase of the study (final study visit). Any 
concomitant medication(s), including herbal preparations, taken during the study will be 
recorded in the electronic case report form (eCRF).
4.7.1
Permitted Concomitant Medications
Investigators may prescribe concomitant medications or treatments deemed necessary to 
provide adequate supportive care except for those medications identified as “excluded” as 
listed in Section 4.7.2. Specifically, subjects should receive full supportive care during the 
study, including transfusions of blood and blood products, and treatment with antibiotics, 
anti-emetics, anti-diarrheals, and analgesics, and other care as deemed appropriate, and in 
accordance with their institutional guidelines.

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4.7.2
Prohibited Concomitant Medications
Other than the medications described above, use of concomitant medications including over-
the-counter medications, herbal supplements, vitamins, etc throughout the study is 
discouraged. 
The following medications are exclusionary. The sponsor must be notified if a subject 
receives any of these during the study.
1. Any investigational agent from 28 days prior to randomization through the end of the 
follow-up period
2. Any intranasal medication from 10 days prior to through 10 days post investigational 
product administration
3. Receipt of influenza antiviral therapy or antiviral agents within 48 hours prior to 
investigational product administration or expected receipt of influenza antiviral therapy 
or antiviral agents through the end of the study period
4.8
Statistical Evaluation
4.8.1
General Considerations
Tabular summaries will be presented by treatment group. Categorical data will be 
summarized by the number and percentage of subjects in each category. Continuous 
variables will be summarized by descriptive statistics. Additional details of statistical 
analyses will be described in the statistical analysis plan.
Definitions of Analysis Populations
The intent-to-treat (ITT) population: The ITT includes all randomized subjects.
As-Treated Population (ATP): The ATP includes all subjects who receive any amount of 
investigational product. Subjects will be included in the ATP according to the investigational 
product received regardless of treatment assigned by randomization.
Immunogenicity population: Immunogenicity population includes all subjects in the ATP 
who have no major protocol deviations judged to have the potential to interfere with the 
generation or interpretation of an immune response to investigational product. 

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4.8.2
Sample Size
HAI Immunogenicity
It is expected that for each analysis of immunogenicity, 90% of subjects will be evaluable. 
The resulting sample size of ~60 evaluable subjects per arm would produce a 95% 
confidence interval (CI) within 14 percentage points of the observed proportion of subjects 
seroconverting. An estimate of 40% for the proportion of subjects seroconverting was used 
for the purposes of CI calculations.
Assuming that the seroconversion rate in the A/Bolivia H1N1 strain (2015-2016 formulation) 
ranged from 10% to 40%, based on 25% of the rate difference, the sample size of 60 
evaluable subjects per arm would result in approximately 80% power to detect a statistically 
significant difference in the seroconversion rate comparing the A/Bolivia H1N1 strain (2015-
2016 formulation) to the replacement H1N1 strain selected for the 2017-2018 vaccine 
formulation (A/Slovenia/2903/2015). Table 4.8.2-1 summarizes the study power based on 
various assumptions. 
Table 4.8.2-1
Power Calculations
Percentage of Subjects with Immune 
Response
Absolute 
Difference (%)
N Per Group
Power (%)
A/Bolivia Strain
A/Slovenia Strain
10
25
15
60
58
30
20
60
78
35
25
60
91
40
30
60
97
50
40
60
99
20
35
15
60
45
40
20
60
67
45
25
60
84
50
30
60
94
30
30
45
60
39
50
20
60
61
55
25
60
79
60
30
60
92
40
55
15
60
37
60
20
60
59
65
25
60
79
70
30
60
92

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Shedding
It is expected that for each analysis of shedding, 90% of subjects will be evaluable. The 
resulting sample size of ~60 evaluable subjects per arm would produce a 95% CI within 
15 percentage points of the observed proportion of subjects who shed. An estimate of 50% 
for the proportion of subjects shedding influenza vaccine virus was used for the purposes of 
sample size calculations, as this value was statistically conservative (ie, had the highest 
variability).
4.8.3
Analyses of Immunogenicity and Shedding……
4.8.3.1
Primary Endpoint Analysis 
The primary endpoint is the strain-specific HAI antibody seroconversion rates, defined as at 
least 4-fold increase from baseline through Day 28 and Day 56. The proportion of subjects 
who had seroconversion will be summarized at Days 28 and 56 visits by strain and treatment. 
Its corresponding 95% exact CI will be provided.   
The difference in proportion between the A/Bolivia H1N1 strain (2015-2016) and the 
replacement H1N1 strain selected for the 2017-2018 vaccine formulation will be tested by 
Cochran–Mantel–Haenszel (CMH) test adjusting for the prior flu vaccination status. If the 
number of subjects in any stratum is too small, Fisher’s exact test will be used without 
adjusting for the prior flu vaccination status. If it is evident that the proportion is confounded 
with some of other demographic and baseline disease characteristic variables, the 
confounding variables will be adjusted.    
4.8.3.2
Secondary Endpoint Analyses 
Geometric mean titers (GMTs) and geometric mean fold rises (GMFRs) of HAI antibody,
neutralizing antibody, and nasal IgA will be summarized by strain and treatment at Days 28 
and 56 visits. Corresponding 95% CI will be calculated assuming log normal distribution. 
Using the results of the qRT-PCR method, the proportion of subjects who shed vaccine will 
be summarized by treatment, strain, and dose number based on the same method as for the 
primary analysis. The number of days of shedding will be summarized descriptively by
treatment, strain, dose number, and baseline serostatus. The viral titer will be calculated by 
day, strain, dose number, and baseline serostatus.
The strain-specific neutralizing antibody seroconversion rates (≥ 4-fold increase from 
baseline), and strain-specific nasal IgA increase (≥ 2-fold increase from baseline) at Days 28 

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and 56 visits will be summarized descriptively using the same method as for the primary 
endpoint. 
4.8.3.3
Exploratory Endpoint Analyses
Analyses of immune response will be conducted based on newly identified specific assays to 
characterize immune response.
Using the results of culture-based methods, the proportion of subjects who shed vaccine, the 
number of days of shedding, and the viral titer will be summarized using the same methods 
as described in Section 4.8.3.2.
4.8.3.4
Subgroup Analyses
Subgroup analysis by baseline serostatus and vaccination status will be conducted for the 
primary and secondary endpoints. 
4.8.4
Safety……….
Analysis of Adverse Events
Adverse events will be coded using the Medical Dictionary for Regulatory Activities 
(MedDRA) by system organ class (SOC) and preferred term (PT). Specific AEs will be 
counted once for each subject for calculating rates, but will be presented in total in subject 
listings. In addition, if the same adverse event (AE) occurs multiple times within a particular 
subject, the highest severity and level of causality will be reported. If any associations of 
interest between AEs and baseline characteristics are observed, additional stratified results 
may be presented. All treatment-emergent AEs will be summarized overall and by MedDRA 
SOC and PT, by severity and relationship to investigational product. In addition, summaries 
of deaths, SAEs, and treatment discontinuations due to AEs will be provided.
4.8.5
Interim Analysis
No interim analyses are planned.

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5
ASSESSMENT OF SAFETY
5.1
Definition of Adverse Events
The ICH Guideline for Good Clinical Practice E6(R1) defines an AE as:
Any untoward medical occurrence in a patient or clinical investigation subject 
administered a pharmaceutical product and which does not necessarily have a causal 
relationship with this treatment. An AE can therefore be any unfavorable and unintended 
sign (including an abnormal laboratory finding), symptom, or disease temporally 
associated with the use of a medicinal product, whether or not considered related to the 
medicinal product.
An AE includes but is not limited to any clinically significant worsening of a subject’s 
pre-existing condition. An abnormal laboratory finding (including ECG finding) that requires 
medical intervention by the investigator, or a finding judged by the investigator as medically 
significant should be reported as an AE. If clinical sequelae are associated with a laboratory 
abnormality, the diagnosis or medical condition should be reported (eg, renal failure, 
hematuria) not the laboratory abnormality (eg, elevated creatinine, urine red blood cell
increased). 
AEs may be treatment emergent (ie, occurring after initial receipt of investigational product) 
or nontreatment emergent. A nontreatment-emergent AE is any new sign or symptom, 
disease, or other untoward medical event that begins after written informed consent has been 
obtained but before the subject has received investigational product. 
Elective treatment or surgery or preplanned treatment or surgery (that was scheduled prior to 
the subject being enrolled into the study) for a documented pre-existing condition that did not 
worsen from baseline is not considered an AE (serious or nonserious). An untoward medical 
event occurring during the prescheduled elective procedure or routinely scheduled treatment 
should be recorded as an AE or SAE.
5.2
Definition of Serious Adverse Events
An SAE is any AE that:
•
Results in death
•
Is immediately life-threatening
•
Requires inpatient hospitalization or prolongation of existing hospitalization 
•
Results in persistent or significant disability/incapacity 

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•
Is an important medical event that may jeopardize the subject or may require medical 
intervention to prevent one of the outcomes listed above
Medical or scientific judgment should be exercised in deciding whether expedited 
reporting is appropriate in this situation. Examples of medically important events are 
intensive treatment in an emergency room or at home for allergic bronchospasm, blood 
dyscrasias, or convulsions that do not result in hospitalizations; or development of drug 
dependency or drug abuse.
5.3
Recording of Adverse Events
AEs will be recorded on the eCRF using a recognized medical term or diagnosis that 
accurately reflects the event. AEs will be assessed by the investigator for severity, 
relationship to the investigational product, possible etiologies, and whether the event meets 
criteria of an SAE and therefore requires immediate notification to the sponsor (see 
Section 5.4). See Section 5.2 for the definition of SAEs and Section 10.2 for guidelines for 
assessment of severity and relationship. 
If an AE evolves into a condition that meets the regulatory definition of “serious,” it will be 
reported on the SAE Report Form.
5.3.1
Time Period for Collection of Adverse Events
AEs will be collected from time of signature of informed consent, throughout the treatment 
period and including the follow-up period, Day 56, last contact.
All SAEs will be recorded from the time of informed consent.
For nontreatment-emergent AEs (ie, AEs that occur during the period from the time informed 
consent is signed but prior to the subject receiving investigational product), only AEs 
associated with protocol-related procedures should be reported. After the start of treatment, 
all treatment-emergent AEs (TEAEs; Section 5.1) should be reported.
5.3.2
Follow-up of Unresolved Adverse Events
Any AEs that are unresolved at the subject’s last AE assessment in the study are followed up 
by the investigator for as long as medically indicated, but without further recording in the 
eCRF. MedImmune retains the right to request additional information for any subject with 
ongoing AE(s)/SAE(s) at the end of the study, if judged necessary.

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5.3.3
Deaths……….
All deaths that occur during the study, including the protocol-defined follow-up period must 
be reported as follows:
•
Death clearly the result of disease progression should be reported and documented in the 
electronic case report form (eCRF) but should not be reported as an SAE.
•
Where death is not due (or not clearly due) to disease progression, the AE causing the 
death must be reported as an SAE within 24 hours. The report should contain a comment 
regarding the co-involvement of disease progression, if appropriate, and should assign 
main and contributory causes of death.
•
Deaths with an unknown cause should always be reported as an SAE. A post-mortem 
(autopsy) may be helpful in the assessment of the cause of death, and if performed a copy 
of the post-mortem results should be forwarded to the sponsor representative(s) within 
the usual timeframes (refer to Section 5.4 for additional information).
5.4
Reporting of Serious Adverse Events
All SAEs have to be reported, whether or not considered causally related to the 
investigational product, or to the study procedure(s). All SAEs will be recorded in the eCRF.
If any SAE occurs in the course of the study, then investigators or other site personnel must
inform the appropriate sponsor representative(s) within 1 day, ie, immediately but no later 
than 24 hours after becoming aware of the event.
The designated sponsor representative works with the investigator to ensure that all the 
necessary information is provided to the sponsor’s patient safety data entry site within 
1 calendar day of initial receipt for fatal and life-threatening events and within 5 calendar 
days of initial receipt for all other SAEs.
For fatal or life-threatening AEs where important or relevant information is missing, active 
follow-up is undertaken immediately. Investigators or other site personnel inform sponsor 
representatives of any follow-up information on a previously reported SAE within 1 calendar 
day, ie, immediately but no later than 24 hours after becoming aware of the event.
Once the investigators or other site personnel indicate an AE is serious in the electronic data 
capture (EDC) system, an automated email alert is sent to inform the designated sponsor 
representative(s).

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If the EDC system is not available, then the investigator or other study site personnel reports 
an SAE to the appropriate sponsor representative by telephone. The sponsor representative 
will advise the investigator/study site personnel how to proceed.
5.5
Other Events Requiring Immediate Reporting
5.5.1
Overdose……….
An overdose is defined as a subject receiving a dose of investigational product in excess of 
that specified in the Package Insert, unless otherwise specified in this protocol.
•
An overdose with associated AEs is recorded as the AE diagnosis/symptoms on the 
relevant AE modules in the eCRF and on the Overdose eCRF module.
•
An overdose without associated symptoms is only reported on the Overdose eCRF 
module.
If an overdose on a MedImmune investigational product occurs during the course of the 
study, then the investigator or other site personnel inform appropriate sponsor representatives 
immediately, or no later than 24 hours after becoming aware of the event.
The designated sponsor representative works with the investigator to ensure that all relevant 
information is provided to the sponsor’s Patient Safety data entry site.
For overdoses associated with an SAE, the standard reporting timelines apply; see Section
5.4. For other overdoses, reporting must occur within 30 days.
5.6
Solicited Symptoms 
Solicited symptoms are events that are considered likely to occur post dosing. For this study, 
solicited symptoms include:
•
Fever ≥ 100.4°F (38.0°C) by any route
•
Runny/stuffy nose
•
Sore throat
•
Cough
•
Headache
•
Generalized muscle aches
•
Decreased activity level (lethargy) OR tiredness/weakness
•
Decreased appetite

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Collection of specific solicited symptoms (sore throat, headache, generalized muscle aches) 
will be omitted when, according to the judgment of the investigator, the subject is too young 
to reliably report a particular symptom.
The reporting period for solicited symptoms for subjects is 14 days after each dose.
6
STUDY AND DATA MANAGEMENT
6.1
Training of Study Site Personnel
Before the first subject is entered into the study, a MedImmune representative will review 
and discuss the requirements of the protocol and related documents with the investigational 
staff and also train them in any study-specific procedures and system(s) utilized.
The Principal Investigator will ensure that appropriate training relevant to the study is given 
to all of these staff, and that any new information relevant to the performance of this study is 
forwarded to the staff involved.
The Principal Investigator will maintain a record of all individuals involved in the study 
(medical, nursing, and other staff).
6.2
Monitoring of the Study
During the study, a MedImmune representative will have regular contacts with the study site, 
including visits to:
•
Provide information and support to the investigator(s)
•
Confirm that facilities remain acceptable
•
Confirm that the investigational team is adhering to the protocol, that data are being 
accurately and timely recorded in the eCRFs, that biological samples are handled in 
accordance with the Laboratory Manual and that study drug accountability checks are 
being performed
•
Perform source data verification (a comparison of the data in the eCRFs with the 
subject’s medical records at the hospital or practice, and other records relevant to the 
study) including verification of informed consent of participating subjects. This will 
require direct access to all original records for each subject (eg, clinic charts)
•
Ensure withdrawal of informed consent to the use of the subject’s biological samples is 
reported and biological samples are identified and disposed of/destroyed accordingly, and 
the action is documented, and reported to the subject.

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The MedImmune representative will be available between visits if the investigator(s) or other 
staff at the center needs information and advice about the study conduct.
6.2.1
Source Data
Refer to the Clinical Study Agreement for location of source data.
6.2.2
Study Agreements
The Principal Investigator at each/the center should comply with all the terms, conditions, 
and obligations of the Clinical Study Agreement, or equivalent, for this study. In the event of 
any inconsistency between this protocol and the Clinical Study Agreement, the terms of 
protocol shall prevail with respect to the conduct of the study and the treatment of subjects 
and in all other respects, not relating to study conduct or treatment of subjects, the terms of 
the Clinical Study Agreement shall prevail.
Agreements between MedImmune and the Principal Investigator must be in place before any 
study-related procedures can take place, or subjects are enrolled.
6.2.3
Archiving of Study Documents
The investigator follows the principles outlined in the Clinical Study Agreement.
6.3
Study Timetable and End of Study
An individual subject will be considered to have completed the study if the subject was 
followed through their last protocol-specified visit/assessment (including telephone contact)
regardless of the number of doses of investigational product that was received. 
Subjects will be considered not to have completed the study if consent was withdrawn or the 
subject was lost to follow-up (see Sections 4.1.5 and 4.1.6).
The end of the study (“study completion”) is defined as the date of the last protocol-specified 
visit/assessment (including telephone contact) for the last subject in the study. 
6.4
Data Management 
Data management will be performed by MedImmune Data Management staff or other party
according to the Data Management Plan.

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An electronic data capture system will be used for data collection and query handling. The 
investigator will ensure that data are recorded in the eCRFs as specified in the study protocol 
and in accordance with the eCRF instructions provided.
The investigator ensures the accuracy, completeness, and timeliness of the data recorded and 
of the provision of answers to data queries according to the Clinical Study Agreement. The 
investigator will sign the completed eCRFs. A copy of the completed eCRFs will be archived 
at the study site.
6.5
Medical Monitor Coverage
Each subject’s legal representative will be provided with contact information for the 
Principal Investigator. In addition, each subject’s legal representative will receive a toll-free 
number intended to provide the subject’s physician access to a medical monitor 24 hours a 
day, 7 days a week in the event of an emergent situation where the subject’s health is deemed 
to be at risk. In this situation, when a subject presents to a medical facility where the treating 
physician or health care provider requires access to a physician who has knowledge of the 
investigational product and the clinical study protocol and the Principal Investigator is not 
available, the treating physician or health care provider can contact a medical monitor 
through this system, which is managed by a third party vendor.
7
ETHICAL AND REGULATORY REQUIREMENTS
7.1
Subject Data Protection
Each subject will be assigned a SID to ensure that personally identifiable information is kept 
separate from the study data. Subject data that are relevant to the trial, eg, demographic 
information, physical or mental health condition, diagnosis, comorbidities, laboratory test 
results, etc. will only be collected with the subject’s informed consent. The Informed Consent 
Form will incorporate (or, in some cases, be accompanied by a separate document 
incorporating) wording that describes how subject data will be collected, used, and 
distributed in compliance with relevant data protection and privacy legislation.
Extra precautions will be taken to preserve confidentiality and prevent genetic data being 
linked to the identity of the subject. MedImmune will not provide individual genotype results 
to subjects, any insurance company, any employer, their family members, general physician 
or any other third party, unless required to do so by law.

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7.2
Ethics and Regulatory Review
The Institutional Review Board/Independent Ethics Committee (IRB/IEC) responsible for 
each site must review and approve the final study protocol, including the final version of the 
Informed Consent Form and any other written information and/or materials to be provided to 
the subject’s legal representative. The IRB/IEC must also approve all advertising used to 
recruit subjects for the study. The investigator is responsible for submitting these documents 
to the applicable IRB/IEC, and distributing them to the study site staff.
The opinion of the IRB/IEC must be given in writing. The investigator must provide a copy 
of the written approval to MedImmune before enrolment of any subject into the study. 
MedImmune should approve any substantive modifications to the Informed Consent Form 
that are needed to meet local requirements.
If required by local regulations, the protocol must be re-approved by the IRB/IEC annually.
Before the study is initiated, MedImmune will ensure that the national regulatory authority in 
each country has been notified and their approval has been obtained, as required. 
MedImmune will provide safety updates/reports according to local requirements, including 
suspected unexpected serious adverse reactions where relevant, to regulatory authorities, 
IRB/IEC, and principal investigators.
Each Principal Investigator is responsible for providing reports of any serious and 
unexpected adverse drug reactions from any other study conducted with the investigational 
product to the IRB/IEC. MedImmune will provide this information to the Principal 
Investigator so that he/she can meet these reporting requirements.
7.3
Informed Consent
Informed consent of each subject will be obtained through a written and verbal explanation 
process that addresses all elements required by International Council for Harmonisation 
(ICH)/Good Clinical Practice (GCP). MedImmune will develop a core informed consent 
form for use by all investigators in the clinical study. MedImmune must approve any 
modifications to the informed consent form that are needed to meet local requirements.
The Principal Investigator(s) at each center will:
•
Ensure each subject’s legal representative is given full and adequate oral and written 
information about the nature, purpose, possible risk, and benefit of the study

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•
Ensure each subject’s legal representative is notified that they are free to discontinue the 
subject from the study at any time
•
Ensure that each subject’s legal representative is given the opportunity to ask questions 
and allowed time to consider the information provided
•
Ensure each subject’s legal representative provides signed and dated informed consent 
before conducting any procedure specifically for the study
•
Ensure the original, signed Informed Consent Form(s) is/are stored in the Investigator’s 
Study File
•
Ensure a copy of the signed Informed Consent Form is given to the subject’s legal 
representative
•
Ensure that any incentives for subjects who participate in the study as well as any 
provisions for subjects harmed as a consequence of study participation are described in 
the informed consent form that is approved by an IRB/IEC
7.4
Changes to the Protocol and Informed Consent Form
Study procedures will not be changed without the mutual agreement of the Principal 
Investigator and MedImmune.
Substantial changes must be documented in a study protocol amendment. MedImmune will 
distribute amended versions of the protocol to the principle investigator(s). Before 
implementation, amended protocols must be approved by relevant IRB/IEC (see Section 7.2)
and according to local requirements, the national regulatory authority approval. The IRB/IEC 
must also approve revisions to the informed consent form, advertising, and any other written 
information and/or materials resulting from the change to the protocol.
If local regulations require, any unsubstantial changes will be communicated to or approved 
by each IRB/IEC.
7.5
Audits and Inspections
Authorized representatives of MedImmune, a regulatory authority, or an IRB/IEC may 
perform audits or inspections at the center, including source data verification. The purpose of 
an audit or inspection is to systematically and independently examine all study-related 
activities and documents, to determine whether these activities were conducted, and data 
were recorded, analyzed, and accurately reported according to the protocol, Good Clinical 
Practice (GCP), guidelines of the International Council for Harmonisation (ICH), and any 
applicable regulatory requirements. The investigator will contact MedImmune immediately if 
contacted by a regulatory agency about an inspection at the site.

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8
REFERENCES
Ambrose CS, Wu X, Jones T, Mallory RM. The role of nasal IgA in children vaccinated with 
live attenuated influenza vaccine. Vaccine. 2012 Nov 6;30(48):6794-801.    
Fiore AE, Shay DK, Haber P, Iskander JK, Uyeki TM, Mootrey G, et al. Prevention and 
control of influenza. Recommendations of the Advisory Committee on Immunization 
Practices (ACIP). MMWR. 2007;56 (RR-06):1-54.
Coelingh K, Olajide IR, MacDonald P, Yogev R. Efficacy and effectiveness of live 
attenuated influenza vaccine in school-age children. Expert Rev Vaccines. 2015 (Sep 
7);14(10):1331-46.  
Committee for Medicinal Products for Human Use (CHMP), 2016. Guideline on influenza 
vaccines. Available from: 
http://www.ema.europa.eu/docs/en_GB/document_library/Scientific_guideline/2016/07/WC
500211324.pdf
Grohskopf LA, Sokolow LZ, Broder KR, Olsen SJ, Karron RA, Jernigan DB, Bresee JS.
Prevention and control of seasonal influenza with vaccines. Recommendations of the 
Advisory Committee on Immunization Practices — United States, 2016–17 Influenza 
Season. MMWR 2016; 65(5):1-54.
Kilbourne ED. Influenza pandemics of the 20th century. Emerg Infect Dis. 2006
(Jan);12(1):9-14.
Mallory RM, Yi T, Ambrose CS. Shedding of Ann Arbor strain live attenuated influenza 
vaccine virus in children 6-59 months of age. Vaccine. 2011 Jun 10;29(26):4322-7.
Ramet J, Weil-Olivier C, Sedlak W. Influenza vaccination: the paediatric perspective. 
Vaccine. 2007 (Jan 15);25(5):780-7.
US FDA, 2016. FDA information regarding FluMist Quadrivalent vaccine. Available from: 
https://www.fda.gov/BiologicsBloodVaccines/Vaccines/ApprovedProducts/ucm508761.htm

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9
CHANGES TO THE PROTOCOL
9.1
Protocol Amendment 1
Text revisions resulting from this amendment are incorporated in the body of Protocol 
Amendment 1. These changes are summarized below.
1. Protocol Synopsis: Updated to be consistent with the changes made to the body of the 
protocol.
2. Section 3.1 (Description of the Study): Text was updated to reflect a change to Inclusion 
Criterion 1 (Section 4.1.2) from “Age 24 months to < 48 months of age at the time of 
randomization” to “Age 24 months to < 48 months of age at the time of screening” so 
that subjects close to the upper age limit who were already screened for the study before 
the delay in availability of the clinical trial material could still be enrolled.
3. Section 3.1 (Description of the Study): The screening period was extended from 30 days
to 75 days due to a delay in the release of clinical trial material by the sponsor.
4. Section 3.1 (Description of the Study): The duration of subject participation was 
extended from “2 to 3 months” to “3 to 4 months” to reflect extension of the screening 
period from 30 days to 75 days.
5. Section 3.1 (Description of the Study): Figure 3.1-1 was updated to be consistent with the 
screening period extension from 30 days to 75 days.
6. Section 4.1.2 (Inclusion Criteria): Inclusion Criterion 1 (subject age criterion) was 
amended from “Age 24 months to < 48 months of age at the time of randomization” to 
“Age 24 months to < 48 months of age at the time of screening” so that subjects close to 
the upper age limit who were already screened for the study before the delay in 
availability of the clinical trial material could still be enrolled.
7. Section 4.2 (Schedule of Study Procedures): Table 4.2-1, Study Days for screening study 
period amended from “-30 to 1” to “-75 to 1” to reflect extension of the screening period 
from 30 days to 75 days.
8. Section 4.2.1 (Screening Visit): Study Days for screening study period amended from 
“-30 to 1” to “-75 to 1” to reflect extension of the screening period from 30 days to 
75 days.

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10 APPENDICES
10.1
Appendix 10.1 – Signature of Principal Investigator

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Signature of Principal Investigator
A Phase 4 Double-blind Study to Evaluate the Shedding and Immunogenicity of Trivalent 
and Quadrivalent Formulations of FluMist in Children 24 to < 48 Months of Age
I, the undersigned, have reviewed this protocol and I agree to conduct this protocol in 
accordance with ethical principles that have their origin in the Declaration of Helsinki and 
are consistent with the International Council for Harmonisation (ICH) guidelines on Good 
Clinical Practice (GCP), any applicable laws and requirements, and any conditions required 
by a regulatory authority and/or Institutional Review Board/Independent Ethics Committee 
(IRB/IEC). 
I understand that the protocol may not be modified without written approval of the sponsor. 
All changes to the protocol must be submitted to the applicable regulatory authority and 
IRB/IEC, and must be approved by the IRB/IEC prior to implementation except when 
necessary to eliminate immediate hazards to the subjects or when the change(s), as deemed 
by the sponsor, involves only logistical or administrative changes. Documentation of 
IRB/IEC approval must be sent to the sponsor immediately upon receipt.
Signature and date: 
Name and title:  
Address including postal code: 
  
Telephone number: 
Site/Center Number (if available)
This document contains confidential information, which should not be copied, referred to, released, or published 
without written approval from MedImmune or AstraZeneca. Investigators are cautioned that the information in 
this protocol may be subject to change and revision.

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10.2
Appendix 10.2 - Additional Safety Guidance
Further Guidance on the Definition of a Serious Adverse Event (SAE)
Life threatening
‘Life-threatening’ means that the subject was at immediate risk of death from AE as it 
occurred or it is suspected that use or continued use of the product would result in the 
subject’s death. ‘Life-threatening’ does not mean that had an AE occurred in a more severe 
form it might have caused death (eg, hepatitis that resolved without hepatic failure).
Hospitalization
Outpatient treatment in an emergency room is not in itself a serious AE, although the reasons 
for it may be (eg, bronchospasm, laryngeal edema). Hospital admissions and/or surgical 
operations planned before or during a study are not considered AEs if the illness or disease 
existed before the subject was enrolled in the study, provided that it did not deteriorate in an 
unexpected way during the study.
Important Medical Event or Medical Intervention
Medical and scientific judgment should be exercised in deciding whether a case is serious in 
situations where important medical events may not be immediately life threatening or result 
in death, hospitalization, disability or incapacity but may jeopardize the subject or may 
require medical intervention to prevent one or more outcomes listed in the definition of 
serious. These should usually be considered as serious.
Simply stopping the suspect drug does not mean that it is an important medical event; 
medical judgment must be used.
Examples of such events are:
•
Angioedema not severe enough to require intubation but requiring intravenous 
hydrocortisone treatment
•
Hepatotoxicity caused by paracetamol (acetaminophen) overdose requiring treatment 
with N-acetylcysteine
•
Intensive treatment in an emergency room or at home for allergic bronchospasm
•
Blood dyscrasias (eg, neutropenia or anemia requiring blood transfusion) or convulsions 
that do not result in hospitalization
•
Development of drug dependency or drug abuse

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Assessment of Severity
Assessment of severity is one of the responsibilities of the investigator in the evaluation of 
AEs and SAEs. The determination of severity should be made by the investigator based upon 
medical judgment and the severity categories of Grade 1 to 5 as defined below.
Grade 1
An event of mild intensity that is usually transient and may 
require only minimal treatment or therapeutic intervention. The 
event does not generally interfere with usual activities of daily 
living.
Grade 2
An event of moderate intensity that is usually alleviated with 
additional specific therapeutic intervention. The event 
interferes with usual activities of daily living, causing 
discomfort but poses no significant or permanent risk of harm 
to the subject.
Grade 3
A severe event that requires intensive therapeutic intervention. 
The event interrupts usual activities of daily living, or 
significantly affects the clinical status of the subject.
Grade 4
An event, and/or its immediate sequelae, that is associated with 
an imminent risk of death or with physical or mental 
disabilities that affect or limit the ability of the subject to 
perform activities of daily living (eating, ambulation, toileting, 
etc).
Grade 5
Death as a result of an event.
It is important to distinguish between serious criteria and severity of an AE. Severity is a 
measure of intensity whereas seriousness is defined by the criteria in Section 5.2. A Grade 3 
AE need not necessarily be considered an SAE. For example, a Grade 3 headache that 
persists for several hours may not meet the regulatory definition of an SAE and would be 
considered a nonserious event, whereas a Grade 2 seizure resulting in a hospital admission 
would be considered an SAE.

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Assessment of Relationship
Relationship to Investigational Product
The investigator is required to provide an assessment of relationship of AEs and SAEs to the 
investigational product. The following factors should be considered when deciding if there is 
a “reasonable possibility” that an AE may have been caused by the investigational product.
•
Time Course. Exposure to suspect investigational product. Has the subject actually 
received the suspect investigational product? Did the AE occur in a reasonable temporal 
relationship to the administration of the suspect investigational product?
•
Consistency with known investigational product profile. Was the AE consistent with the 
previous knowledge of the suspect investigational product (pharmacology and 
toxicology) or products of the same pharmacological class? OR could the AE be 
anticipated from its pharmacological properties? 
•
De-challenge experience. Did the AE resolve or improve on stopping or reducing the 
dose of the suspect investigational product?
•
No alternative cause. The AE cannot be reasonably explained by another etiology such as 
the underlying disease, other drugs, or other host or environmental factors.
•
Re-challenge experience. Did the AE reoccur if the suspected investigational product was 
reintroduced after having been stopped? MedImmune would not normally recommend or 
support a re-challenge.
•
Laboratory tests. A specific laboratory investigation (if performed) has confirmed the 
relationship?
In difficult cases, other factors could be considered such as:
•
Is this a recognized feature of overdose of the investigational product?
•
Is there a known mechanism?
Causality of ‘related’ is made if following a review of the relevant data, there is evidence for 
a ‘reasonable possibility’ of a causal relationship for the individual case. The expression 
‘reasonable possibility’ of a causal relationship is meant to convey, in general, that there are 
facts (evidence) or arguments to suggest a causal relationship.
The causality assessment is performed based on the available data including enough 
information to make an informed judgment. With limited or insufficient information in the 
case, it is likely that the event(s) will be assessed as ‘not related’.

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Causal relationship in cases where the disease under study has deteriorated due to lack of 
effect should be classified as no reasonable possibility.
Relationship to Protocol Procedures
The investigator is also required to provide an assessment of relationship of SAEs to protocol 
procedures on the SAE Report Form. This includes nontreatment-emergent SAEs (ie, SAEs 
that occur prior to the administration of investigational product) as well as treatment-
emergent SAEs. A protocol-related SAE may occur as a result of a procedure or intervention 
required during the study (eg, blood collection, washout of an existing medication). The 
following guidelines should be used by investigators to assess the relationship of SAEs to the 
protocol:
Protocol related:
The event occurred due to a procedure/intervention that was described 
in the protocol for which there is no alternative etiology present in the 
subject’s medical record.
Not protocol related: The event is related to an etiology other than the procedure/ 
intervention that was described in the protocol (the alternative etiology 
must be documented in the study subject’s medical record).

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10.3
Appendix 10.3 - National Institute of Allergy and Infectious Disease 
and Food Allergy and Anaphylaxis Network Guidance for 
Anaphylaxis Diagnosis
Sampson HA, Muñoz-Furlong A, Campbell RL, Adkinson FN Jr, Bock SA, Branum A, et al. 
Second symposium on the definition and management of anaphylaxis: Summary report --
Second National Institute of Allergy and Infectious Disease/Food Allergy and Anaphylaxis 
Network symposium. J Allergy Clin Immunol. 2006;117:391-7.
National Institute of Allergy and Infectious Diseases (NAID) and Food Allergy and 
Anaphylaxis Network (FAAN) define anaphylaxis as a serious allergic reaction that is rapid 
in onset and may cause death. They recognize 3 categories of anaphylaxis, with criteria 
designated to capture from 80% of cases (category 1) to > 95% of all cases of anaphylaxis 
(for all 3 categories). 
1. Acute onset of an illness (minutes to several hours) with involvement of the skin, 
mucosal tissue, or both (eg, generalized hives, pruritus or flushing, swollen lips-tongue-
uvula)
AND AT LEAST ONE OF THE FOLLOWING
a.
Respiratory compromise (eg, dyspnea, wheeze-bronchospasm, stridor, reduced peak 
expiratory flow (PEF), hypoxemia)
b. Reduced blood pressure (BP) or associated symptoms of end-organ dysfunction (eg, 
hypotonia [collapse], syncope, incontinence)
2. Two or more of the following that occur rapidly after exposure to a likely allergen for 
that patient (minutes to several hours):
a.
Involvement of the skin-mucosal tissue (eg, generalized hives, itch-flush, swollen 
lips-tongue-uvula)
b. Respiratory compromise (eg, dyspnea, wheeze-bronchospasm, stridor, reduced PEF, 
hypoxemia)
c.
Reduced BP or associated symptoms (eg, hypotonia [collapse], syncope, 
incontinence)
d. Persistent gastrointestinal symptoms (eg, crampy abdominal pain, vomiting)
3. Reduced BP after exposure to known allergen for that patient (minutes to several hours):
a.
Infants and children: low systolic BP (age specific) or greater than 30% decrease in 
systolic BP
b. Adults: systolic BP of less than 90 mm Hg or greater than 30% decrease from that 
person’s baseline

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10.4
Appendix 10.4 – 2016-2017 FluMist Quadrivalent Package Insert

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