A PHASE 2 RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED, MULTIPLE ASCENDING DOSE STUDY TO EVALUATE THE SAFETY, EFFICACY, PHARMACOKINETICS AND PHARMACODYNAMICS OF PF-06252616 IN AMBULATORY BOYS WITH DUCHENNE MUSCULAR DYSTROPHY
Phase: PHASE2
Conditions: Duchenne Muscular Dystrophy
Sponsor: Pfizer

PF-06252616
B5161002
Final Protocol Amendment 2, 15 August 2016
Page 1
A PHASE 2 RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED, 
MULTIPLE ASCENDING DOSE STUDY TO EVALUATE THE SAFETY, 
EFFICACY, PHARMACOKINETICS AND PHARMACODYNAMICS OF 
PF-06252616 IN AMBULATORY BOYS WITH DUCHENNE MUSCULAR 
DYSTROPHY
Compound:
PF-06252616
Compound Name:
Anti-Myostatin
United States (US) Investigational New 
Drug (IND) Number:
113,863
European Clinical Trials Database 
(EudraCT) Number:
2014-002072-92
Protocol Number:
B5161002
Phase:
2
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Document History
Document
Version Date
Summary of Changes and Rationale
Amendment 2
15 August 2016

Incorporation of Protocol Administrative 
letters issued on 01DEC2015, 07JAN2016, 
08FEB2016 and 09MAR2016. 

Schedule of Actives and carried out 
throughout protocol where appropriate.

Removed 6 hour PK and PD collection 
by the time of implementation of 
Amendment 2 a sufficient amount of 
6-hour PK and PD samples will have 
been collected to characterize PK and 
PD. Removal of the timepoint will
remove the burden to patients for this 
testing while maintaining the ability to 
achieve the PK and PD objectives. 

Vital signs moved to align with pre and 
post dosing collection.

Revised the requirements for weight 
collection from either the current visit or 
prior month’s visit.

Clarified window for fecal occult blood 
test.

Revised the timing for collection of 
thigh MRI and Functional assessments 
to provide flexibility while attempting to 
mitigate potential variability that may be 
introduced inconsistent testing. 

Clarified requirements for functional 
testing in non-ambulatory patients.

Clarified the data to be considered by 
the E-DMC for reduction in liver 
monitoring frequency.

Modified the window for investigational 
product administration to align with the 
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observed various site practices.  
Clarified the delivery to include the 
flush time.

Added allowance to stop monitoring for 
Tanner Stage, testicular volume, 
hormone and X-ray, should boys reach 
sexual maturity during the study. 

Added DXA-Whole body to Early 
Termination visit as it was missing from 
prior protocol version. 

Section 1.6 Toxicology-revisions made to 
reflect IB language.

Section 1.7 Clinical Experience-revisions 
made to reflect IB language.

Section 1.8.2 Immunogenicity-revisions 
made to reflect IB language. 

Added provision to allow the E-DMC to 
permit the results from the liver MRI and 
iron indices to be provided to the team and 
sites following their review of data which 
indicate these data are not unblinding to the 
study treatment assignment. 

Section 1.11.3 remove the requirement for 
monitoring Tanner staging for boys who 
reach sexual maturity during the study.

Section 2 Objectives/Endpoints: Added 
secondary objectives to 1) permit evaluation 
of long-term treatment and 2) evaluation of 
functional assessments in sub-group of 
subjects.  Added description of endpoints to 
meet new objectives. Corrected timepoints 
for endpoints. Removed strength testing by 
the MRC scale to reduce the burden of 
testing on subjects. Subjects will still 
undergo myometry testing for strength.

Section 3 Clarified the length of follow-up 
required for subjects who may be enrolling 
in the OLE study.  Clarified the duration of 
the study which has been extended due to 
longer than anticipated time to enroll.  
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Clarified that additional subjects may be 
enrolled if the study is full recruited before 
the interim analysis is completed and no 
safety issues have been observed.  Clarified 
the timing for the E-DMC to consider if the 
study can move to an automated
dose-escalation rather than a manual 
process and/or reduce the liver MRI 
monitoring frequency. Clarified that the 
E-DMC may determine if the liver MRI 
results and serum iron indice data may be 
shared with the study team if a 
determination can be made that the data are 
not unblinding as to the treatment 
assignment. 

Section 4-Expanded the age to include boys 
up to <16 years of age, clarified screening 
results for fecal occult blood test and in 
exclusion item 10, added current or prior 
treatment with anti-myostatin and clarified 
prior utrophin modifier exposure exclusion 
requirements (PACLs 07 Jan 2016 and 
06 Mar 2016). 

Section 5 updated to reflect the use of an 
Investigational Product Manual.  Updated 
the requirements to allow the previous 
month’s weight to be used for dose 
calculation for visits occurring after Day 1.
Modified the masking to include the in-line 
filter of the infusion set. This was added 
due to the potential of higher concentrations 
of the investigational drug produce which 
may be required for older subjects who are 
receiving the higher dose levels.  Provided 
guidance on compliance with dosing. 
Clarified the infusion time (PACL 08 Feb 
2016).

Section 6 updated to reflect changes noted 
in the Schedule of Activities.

Section 7 clarified reporting of abnormal 
findings from physical exams, clarified 
monitoring for sexual maturity, and 
removed the strength testing by MRC scale 
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to reduce the burden of testing on subjects.

Section 9, added the intention of continued 
recruitment if the study completes 
enrollment prior to the time of the IA and 
there are no safety issues identified.  Added 
a description of historic control group to 
evaluate with subjects in sequence Group 1 
who have been treated for 2 years.

Section 9.4, Revised the gamma for futility 
to (-1).

Various administrative changes made 
throughout protocol.
Amendment 1
18 May 2015

Abbreviations-added GLDH, removed 
PESC and UTN.

Schedule of Activities (SoA) revised to 
move Day 1 activities into a separate 
column to help clarify the procedures that 
will occur at baseline versus those that will 
occur on Day 1. 

SOA-Revised the visit window for 
Screening and Baseline to allow for 
additional days at Baseline and removed 
window for Day 1.

SOA corrected Immunogenicity sample at 
baseline (it was previously noted in 
Section 6 but not on the SOA).

SOA added “testicular volume” after 
Tanner Staging for clarity of collection of 
this data.

Clarified the window for vital signs at 
6 hours post dose.

SOA removed the requirements for thigh 
MRI visit 449 and 561 in Period 2. 

SOA separated DXA to whole body and 
spine for clarity of which DXA is to be 
performed at which visit.

SOA updated footnotes; added GLDH for 
lab tests and observation time required 
following investigational product 
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administration, clarified the following: 
collection of stool sample at screening, 
assessments needed for randomization, the 
subject observation time post dosing and for 
the 6 hour PK collection 

SOA and Section 5 clarified Dose 
Administration window for administration
(15 minutes) and requirements for 
administration outside of visit window.  

Section 1, clarified investigational product 
appearance, added GLDH to be used as a 
biomarker for hepatic injury.

Section 2, added GLDH in the list of 
primary clinical laboratory endpoints for 
safety assessment of liver injury; clarified 
collection of the exploratory endpoints for 
T2-mapping and Dixon methods to be 
collected at sites with capabilities.  Clarified 
the assessments for GDF-8 parameters.

Section 3, clarified the process for 
confirmation of exposure in the first 
12 subjects enrolled, removed the E-DMC 
decision at the time of IA to reduce the 
number of thigh MRIs instead the protocol 
will prospectively be changed to only 
collect thigh MRI annually in Period 2.

Section 3 Dose Adjustment-added a 
requirement to confirm the number of doses 
received at each dose level, updated table 
for dose adjustment to removed % 
Transferrin Saturation as criteria for dose 
adjustment, clarified that criteria applied to 
all subjects (active and placebo), clarified 
information to be communicated to assure 
blind is maintained, clarified dose 
adjustment in Sequence Period 2. 

Section 3 Changed the Pfizer Executive 
Steering Committee to “sponsor 
management” to align with the E-DMC 
charter.

Section 4 Inclusion criteria- clarified criteria 
for 4SC to be 1.6 stairs/second (or
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2.5 seconds), clarified the criteria for 
serum iron (1.2 x ULN), serum ferritin 
(140 ng/mL), % transferrin saturation 
50%) and results fecal occult blood testing
to be negative at screening.

Section 4 Exclusion criteria- clarified prior 
“lower limb” fractures, LVEF <55% 
(normal range at screening), concomitant 
medications (permitted and not permitted) 
and additives for the investigational 
product.

Section 4 Randomization, clarified that 
eligibility is based on the 4 SC at screening 
while randomization requires the baseline 
4SC to stratify subjects. 

Section 4 Screen Failures, added criteria for 
allowing re-screening for screen failures 
who fail the 4SC criteria only.

Section 4 Lifestyle clarified caffeine use 
within 24 hours of study visits.

Section 4 Lifestyle removed iron 
supplements to align with the other section 
of the protocol. 

Section 4 Lifestyle added dietary guidelines 
for fecal occult blood test and clarified
dietary preparation for DXA scan.

Section 4 Contraception clarified to align 
with updated protocol template language.

Section 4 Caregiver clarified that they will 
be responsible for completing the C-SSRs at 
each visit.

Section 4 Sponsor Qualified Medical 
Personnel clarified to align with updated 
protocol template language.

Section 4.7.3 Clinical Evaluators clarified 
the requirements for reliability to align with 
the Functional Assessment manual.

Section 5 Study Treatment, updated with 
protocol template language and clarified, 
the window for investigational product 
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administration (15 minutes), the decrease 
in infusion rate following an infusion site 
reaction, guidance for dosing outside of the 
visit window, added the 1 hour observation 
post administration, clarified the 
Investigational Product Storage and added a 
section on destruction of investigational 
drug product, clarified the DAI calculations 
and dose preparation double verification 
requirements and blinding procedures if 
more than 2 subjects are dosed at the same 
time. 

Section Concomitant medication- clarified 
permitted and prohibited medications.   
Added ARB and aldosterone 
blocker/thiazide diuretic as permitted. 
Added bisphosphonates as permitted. 
Added utrophin and treatment with an iron 
supplement and idebenone as prohibited.  
Noted that subjects may be discontinued 
who receive prohibited therapies.

Section 6 Study Procedures updated to align 
with revisions made to the SOA and to 
clarify procedures required for re-screening 
subjects. 

Section 7 Blood Collection added an option 
of an IV cannula for serial blood collection, 
updated the estimated laboratory blood 
volumes and added GLDH to list of clinical 
tests, clarified resuls for WBC and ANC 
and collection of serum for liver biomarker; 
and clarified timing for hormone testing.

Section 7 Electrocardiogram clarified the 
use of reporting results with the Fridericia 
correction. 

Section 7 Cardiac MRI/Echocardiogram, 
clarified preferred method is cardiac MRI, 
data provided by the central imaging vendor 
for cardiac MRI. Clarified method and data 
parameters to be collected for 
echocardiogram.

Section 7 C-SSRs clarified to be conducted 
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via parent proxy at each visit.

Section 7 Liver MRI, clarified who will 
calculate the R2* value for the liver MRI 
and quality of liver MRI.

Section 7 Thigh MRI, clarified not to be 
done after exercise.

Section 7 Additional Research, added 
information about additional research that 
may be performed with imaging 
assessments.

Section 7 Functional Assessments, clarified 
the training for the functional assessments 
and the ongoing quality control measures.

Section 7 4SC, clarified that the method is 
with or without use of hand rails.

Section 7 Trigger- Removed trigger for 
potential accelerated sexual development

Section 7 Trigger- Added trigger for spine 
compression or fracture.

Section 7 PODCI added information about 
the PODCI which had previously been 
omitted.

Section 8 Updates to align with protocol 
template language.

Section 9 Analysis, clarified the IA and 
handling of missing data for efficacy 
analysis

Sections 10-15 updates made to align with 
protocol template language.

Appendices, removed PODCIs for 
11-18 year olds.

Various administrative changes made 
throughout protocol.
Original protocol
18 July 2014
N/A
This amendment incorporates all revisions to date including amendments made at the request 
of country health authorities, institutional review boards/ethics committees (IRBs/ECs), etc.
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Abbreviations
This is a list of abbreviations that may be used in the protocol.
Abbreviation
Term
4SC
four stair climb
6MWD
six minute walk distance
6MWT
six minute walk test
ACE
angiotensin-converting-enzyme
ADA
anti-drug antibodies
AE
adverse event
ALT
alanine aminotransferace
aPTT
activated partial thromboplastin time
ARB
angiotensin II receptor blocker
AST
aspartate aminotransferase 
BMD
bone mineral density
BMP/TGF
bone morphogenetic protein transforming growth factor-
CDC
Center for Disease Control
CIOMS
Council for International Organizations of Medical Sciences
CHMP
Committee for Medicinal Product for Human Use
CL
clearance
CNS
central nervous system
CRF
case report form
CSA
clinical study agreement
CSF
cerebrospinal fluid
C-SSRS
Columbia Suicide Severity Rating Scale
DILI
drug-induced liver injury
DMD
Duchenne muscular dystrophy
DNA
deoxyribonucleic acid
DU
dispensable unit
DXA
dual energy x-ray absorptiometry
EC
ethics committee
ECG
Electrocardiogram
E-DMC
external data monitoring committee 
EDP
exposure during pregnancy
EDTA
edetic acid (ethylenediaminetetraacetic acid)
EF
ejection fraction
ELISA
enzyme-linked immunosorbent assay
EMA
European Medicines Agency
EudraCT
European Clinical Trials Database
FAS
full analysis set
FDA
Food and Drug Administration (United States)
FDAAA
Food and Drug Administration Amendments Act (United States)
FSH
follicle stimulating hormone
FVC
forced vital capacity
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GCP
Good Clinical Practice
GDF-8
growth differentiation factor 8
GGT
gamma-glutamyl transferase
GLDH
glutamate dehydrogenase
IA
interim analysis
IB
investigator’s brochure
ICD
informed consent document
ICH
International Conference on Harmonisation
ID
Identification
IgG1
immunoglobulin G1
IND
investigational new drug application
INR
international normalized ratio
IP
intraperitoneal
IRB
institutional review board
IRC
internal review committee
IRT
interactive response technology
IUD
intrauterine device
IV
intravenous
IVR
interactive voice response
IWR
interactive web response
LBM
lean body mass
LC/MS
liquid chromatography/mass spectrometry
LFT
liver function test
LH
luteinizing hormone
LLN
lower limit of normal
LSLV
last subject last visit 
MHP
mental health provider
MRC
Medical Research Council
MRI
magnetic resonance imaging
MSW
Master’s level Clinical Social Workers
N
number
N/A
not applicable
Nab
neutralizing antibodies
NHP
non-human primate
NOAEL
no observed adverse effect levels
NSAA
Northstar Ambulatory Assessment
OLE
open label extension
PCD
primary completion date
PK/PD
pharmacokinetic/pharmacodynamics
PNP
psychiatric Nurse Practitioners
PODCI
Pediatric Data Outcomes Collection Instrument
POM
proof of mechanism
PPV-23
pneumococcal polysaccharide vaccine
PT
prothrombin time
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PUL
Performance of Upper Limb
RBC
red blood cell
RNA
ribonucleic acid
ROM
range of motion
SAE
serious adverse event
SAP
statistical analysis plan
SC
subcutaneous
SD
Standard deviation
SOP
standard operating procedure
SRSD
single reference safety document
SSID
single subject’s identification
SWFI
sterile water for injection
T4
thyroxine
TEAEs
treatment emergent AEs
TIBC
total iron binding capacity
TK
toxicokinetic
TMDD
Target mediated drug disposition
TSH
thyroid stimulating hormone
ULN
upper limit of normal
US
United States
ULN
upper limit of normal
US
United States
USPI
United States package insert
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PROTOCOL SUMMARY
Background and Rationale
The investigational product PF-06252616, a humanized anti-myostatin (GDF-8) monoclonal 
antibody that neutralizes myostatin (GDF-8) is in development for the treatment of Duchenne 
muscular dystrophy (DMD) to preserve and/or improve muscle function.  Other potential 
indications for PF-06252616 include other muscular dystrophies, muscle frailty conditions 
such as cancer cachexia and sarcopenia and rehabilitation of muscle strength.
The safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of 
PF-06252616 have been demonstrated in healthy adults following administration of either 
single ascending intravenous (IV) or a subcutaneous (SC) dose(s) and, subsequently, repeat 
IV doses in adult healthy subjects.
DMD is the most frequently inherited neuromuscular disease, and predominantly affects 
boys.  It is an X-linked muscular dystrophy caused by a mutation at Xp21 in the gene coding 
for the protein dystrophin (Bushby et al, 2010; Manzur et al, 2008)4,12 which is absent from 
the muscle of boys with DMD.  DMD is the most severe of all muscular dystrophies and is 
characterized by skeletal and cardiac muscle degeneration.  Most boys lose the ability to 
walk between the ages of 10 and 14 (Lamperti & Moggio, 2010).11  Progressive cardiac 
problems manifest in the second decade.  Death occurs in the late teens or early twenties 
(Manzur et al, 2008).12
Protocol B5161002 is a first-in-patient study with PF-06252616.  This study will provide the 
initial clinical assessment of the safety, efficacy, PK and PD of PF-06252616 following 
repeat IV doses in ambulatory boys with DMD.
Objectives and Endpoints
Primary Safety and Efficacy

To determine the safety and tolerability of multiple ascending repeat IV doses of 
PF-06252616 in ambulatory boys with DMD.  Safety will be based on incidence of 
abnormal and clinically relevant laboratory findings, physical examinations, weight, 
vital signs, electrocardiogram (ECG), left ventricular ejection fraction (LVEF) by 
cardiac magnetic resonance imaging (MRI) with gadolinium or echocardiogram (if 
cardiac MRI is not available at the site), liver MRI, dual energy x-ray absorptiometry
(DXA) (bone mineral density), x-ray (bone age) and Columbia Suicide Severity 
Rating Scale (C-SSRS) parameters by Week 49.  Cardiac MRI with gadolinium is the 
preferred method for cardiac imaging.  If the subject has a contraindication to 
gadolinium, cardiac MRI without gadolinium will be acceptable.  Echocardiogram 
may be substituted if it is not possible to perform cardiac MRI (if cardiac MRI is not 
available at the site).
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
To demonstrate the efficacy of treatment with IV doses of PF-06252616 based on an 
observed mean change from baseline on function (4 Stair Climb) as compared to 
placebo following 49 weeks of treatment.
Secondary

To characterize the effects of PF-06252616 on muscle strength and other functional 
assessments (Forced Vital Capacity [FVC], Northstar Ambulatory Assessment
[NSAA], range of motion [ROM], Performance of Upper Limb [PUL], six minute 
walk distance [6MWD]) compared to placebo.

To evaluate the PD activity of PF-06252616 based on the percent change of muscle 
volume as measured on MRI from baseline as compared to placebo.

To evaluate the PD profile of PF-06252616 based on GDF-8 (myostatin) modulation 
in blood.

To characterize the PK profile of PF-06252616.

To evaluate the immunogenicity (anti-drug antibodies [ADA] and neutralizing 
antibodies [NAb]) of PF-06252616.

To characterize the long-term effects following approximately 2-years of treatment
with PF-06252616 on functional assessments compared to historical control.  

To characterize the effects of PF-06252616 on muscle strength and functional 
assessments compared to placebo in a subset of subjects who may demonstrate a
rapid disease decline and with relatively low variability over a one-year period.
Exploratory

To evaluate biomarkers (lean body mass [LBM] by DXA, muscle quality by MRI, 
quantification of blood biomarkers) that may be informative in demonstrating the 
pharmacologic effect of PF-06252616.

To evaluate biomarkers that may be informative for monitoring hepatic liver injury in 
the setting of dystrophic muscle.

To evaluate the Functional Health Status (Pediatric Data Outcomes Collection 
Instrument [PODCI] questionnaire).

To evaluate long term safety of PF-06252616 in subjects treated for >1 year.

To evaluate duration of treatment response following withdrawal and/or continuation 
of treatment for >1 year.

To evaluate response in a delayed treatment group.
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Study Design
This is a Phase 2 randomized, 2-period, double-blind, placebo-controlled, multiple ascending 
dose study to evaluate the safety, efficacy, PK and PD of PF-06252616 administered to 
ambulatory boys diagnosed with DMD.  Three IV infused dose levels (5, 20 and 40 mg/kg) 
administered every 28 days will be investigated in a within subject dose escalating fashion.
Approximately 105 eligible subjects will be randomly assigned to 1 of 3 sequence groups and 
receive investigational product for approximately 96 weeks (2 treatment periods of 
approximately 48 weeks each) stratified by their baseline time to complete the 4 stair climb 
(either or 8 seconds).
Sequence 1 (n=35):
Period 1: Active treatment (PF-06252616) within subject dose escalation (5, 20 and 
40 mg/kg)
Period 2: Active treatment (PF-06252616) at the maximum tolerated dose in Period 1
Sequence 2 (n=35):
Period 1: Active treatment (PF-06252616) within subject dose escalation (5, 20 and 
40 mg/kg)
Period 2: Placebo
Sequence 3 (n=35):
Period 1: Placebo
Period 2: Active treatment (PF-06252616) within subject dose escalation (5, 20 and 
40 mg/kg)
Each dose level will be explored in a dose escalating fashion within subjects, starting with 
the lowest dose.  At each dose level, dosing will be administered over a 2-hour IV infusion 
every 4 weeks for a total of 16 weeks (4 doses).  Dose escalation within a subject will occur 
following the planned fourth dose within each dose level.  Subjects will move from Period 1 
to Period 2 without a pause between periods.
Individual dose escalation decisions will be conducted for each subject by the Investigator, 
sponsor Medical Monitor and a Designated Reviewer.  This process will occur from time of 
the first subject being enrolled and continue until the time of the IA.  At the time of IA (or 
sooner as determined by the External Data monitoring committee’s review of unblinded 
data), if adequate safety has been demonstrated at each dose level as determined by an
External Data Monitoring Committee (E-DMC), subsequent dose escalation will occur
without confirmation of the individual safety data prior to dose escalation. 
From the time of study initiation through completion of the study, the sponsor will conduct 
routine safety monitoring of the blinded data per the safety review plans.  In addition, the
E-DMC will review unblinded safety data.  The E-DMC may determine if it is necessary to 
close or adjust a dose level within the study or continue with individual level dose escalation 
review.
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In the event that the E-DMC determines that adequate safety has been established at each 
dose level (following the IA or sooner), they will also consider if the requirement for liver
MRI can be reduced to an annual safety assessment (based on normal findings on the liver 
MRI).  
The individual subject dose adjustment will be determined by three parties including the 
Investigator, sponsor Medical Monitor and a Designated Reviewer.  Following the planned 
fourth dose within each dose level, all available safety data for an individual subject will be 
reviewed by the Investigator, sponsor Medical Monitor and Designated Reviewer to 
determine the appropriate dose adjustment.
Dose adjustment criteria will be used to determine if the dosing or dose level should be:

Escalated to the next dose level.

Maintained at the current dose level.

Reduced to a lower dose level, or

Stop dosing.
Subjects who complete this study may be invited to participate in an open label extension 
study. 
Investigational Product Administration
Subjects will be treated with IV infused PF-06252616 or placebo in this double-blind, 
placebo controlled study.  Allocation of subjects to the sequence groups (treatment 
assignment) will proceed through the use of an Interactive Response Technology (IRT) 
System [Interactive Web Response (IWR)/Interactive Voice Response (IVR) system] by the 
unblinded dispensing personnel.
PF-06252616 will be provided by Pfizer as a lyophilized powder for injection in single use, 
sterile glass vials.  Each vial will be sealed with a coated stopper and an aluminum overseal 
and labeled according to local regulatory requirements.  The drug product must be 
reconstituted with sterile water for injection (SWFI) for IV infusion.  The reconstituted 
PF-06252616 drug product is a clear to slightly opalescent solution and colorless to slightly 
colored in appearance. 
The placebo will be provided by Pfizer as a solution for injection.  The placebo is supplied in 
a glass vial sealed with a coated chlorobutyl serum stopper and an aluminum overseal and 
labeled according to local regulatory requirements.
The placebo does not match the active drug product and therefore, the supplies are provided 
as open label vials.  Trained unblinded site staff personnel who are appropriately qualified 
(eg, pharmacist, pharmacist technician) are required to prepare the investigational product.
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Details of the drug product and its preparation are provided in the dosage and administration 
instructions in the Investigational Product Manual.
Following preparation of the investigational product (PF-06252616 or placebo) by the 
unblinded site staff personnel, the prepared product will be provided to blinded staff 
personnel for administration. 
At the time of investigational product administration, topical anesthetics (eg, topical 
lidocaine at the site of infusion) may be administered to subjects, consistent with institutional 
guidelines.
The IV infusion should be administered by qualified healthcare professionals trained to 
detect any infusion related issues.  Infusion times, rates, any infusion interruptions or 
infusion rate reduction, will be recorded.  The study drug should be infused over a 2-hour 
period where time 0 is the beginning of the infusion and include the flush time. Subjects 
should be observed for 1-hour following completion of the investigational product 
administration. 
Statistical Method for Primary Efficacy
The sample size is based on the primary endpoint of demonstrating efficacy of change from 
baseline on a 4 stair climb timed function test as compared to placebo at 49 weeks.  To detect 
a 2.5 second difference in change from baseline in 4 stair climb based on a difference
between the active treatment and the placebo treatment in Period 1 assuming a standard 
deviation of 4.0 with 80% power at =0.05 (two-sided), a 2:1 treatment allocation and one
IA, a total of 96 subjects should complete 49 weeks of dosing for this assessment.  Assuming 
a 10% attrition rate, approximately 105 subjects should be enrolled (70 subjects receiving 
PF-06252616 and 35 subjects receiving placebo) in order to ensure a sufficient number of 
subjects will complete this assessment.  If there are no safety issues and enrollment has 
completed, additional subjects may be enrolled prior to the time of the interim analysis. 
These additional subjects may help off-set any unforeseen variability that may occur outside 
the presumed standard deviation for this age group.
One IA is planned to evaluate futility and efficacy after approximately 50% of the subjects 
have completed through Week 49.  Alpha- and beta-spending functions will be used to 
determine the cutoffs for efficacy and futility at the interim based on the observed number of 
subjects in the IA.  The gamma family spending functions will be used to appropriately 
account for error spending and adjust for the observed information at the time of the IA and
conservative boundaries (-1) will be used to define the futility and efficacy boundaries.  
The cutoff used at the IA will be calculated based on the percentage of subjects included at 
the IA to ensure appropriate protection of the type I error.  Further details regarding the IA
and simulations are included in the statistical analysis plan (SAP).
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At the time of the IA if the E-DMC makes a recommendation to the sponsor management to
modify or terminate the study based on establishing efficacy and safety of PF-06252616, the 
sponsor management will review the recommendation with regulatory agencies prior to 
making any changes to the study design, including termination of the study.
Continuous variables will be summarized by the number (N), mean, median, standard 
deviation, minimum and maximum.  Categorical variables will be summarized by percent 
and counts.  All summaries will be displayed by treatment group and/or period depending on 
the endpoint.  Efficacy data will be listed, tabulated and graphically represented, as 
appropriate.  Model assumptions will be tested using appropriate statistical or graphical 
techniques.
All analyses will be based on the full analysis set (FAS) which includes all randomized 
subjects who have received at least one dose of study drug.  Additionally analyses based on a 
per protocol analysis set may also be performed.
Change from baseline in 4 stair climb will be analyzed using a longitudinal mixed effects 
model.  The baseline result, treatment, time and treatment by time interaction will be 
included as fixed effects in the model.  Subject will be included as a random effect and the 
model will be fit with an unstructured covariance for the repeated measures.  The distribution 
of the time to climb 4 stairs is assumed to be right skewed.  Transformations of the time to 
climb 4 stairs (including the log transformation) will be evaluated to ensure the normality 
assumption is met.  Contrasts will be created to estimate the differences in change from 
baseline time in 4 stair climb at the end of each dose treatment levels for Period 1 (Week 17, 
Week 33 and Week 49).  The final analysis of the primary endpoint will be performed at 
Week 49, though data will continue to be collected through Week 97.  Additionally, 
non-Gaussian models may be explored in the case of non-normal data for the time to climb 
4 stairs.
Missing data will be handled using maximum likelihood techniques for a mixed effects 
model.  This analysis is unbiased under the assumption of missing at random when the model 
assumptions hold.  Subjects who lose the ability to climb 4 stairs and/or ambulate will be 
missing not at random.  Additional imputation methods to assess the sensitivity of the 
analysis to missing not at random data will also be performed.  A completer analysis will also 
be conducted as a sensitivity analysis.
A sensitivity analysis of the time to climb 4 stairs will be based on the velocity (defined as 
the reciprocal of time).  This analysis will use the same longitudinal model, but subjects who 
can no longer ambulate will be analyzed with a velocity of 0 instead of a missing time to 
climb 4 stairs at that time point, as specified above.  Thus the missing data will no longer be 
handled by the maximum likelihood techniques under the missing at random assumption for 
subjects who can longer complete the 4 stair climb.  Based on the number of subjects who 
cannot complete the function test at Week 49, a zero inflation model may also be explored 
for the velocity endpoint.
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Additionally, a non-parametric sensitivity analysis may be performed on the Week 49 data if 
there is a large number of subjects who can no longer ambulate.  The proportion of subjects 
who can no longer complete the test will also be compared between the two treatment groups 
at the Week 49 time point along with a time to failure analysis comparing the two treatment 
groups based on the ability to complete the test.
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SCHEDULE OF ACTIVITIES
The Schedule of Activities tables provide an overview of the protocol visits and procedures for Period 1, 2 and Early Withdrawal. In 
order to accommodate the scheduling, assessments may be conducted on separate days within the visit window; however the order of 
completion of assessments must be adhered to.  Refer to the STUDY PROCEDURES and ASSESSMENTS sections of the protocol 
for detailed information on each procedure and assessment required for compliance with the protocol. 
The investigator may schedule visits (unplanned visits) in addition to those listed on the schedule of activities, in order to conduct 
evaluations or assessments required to protect the wellbeing of the subject.
Study Flowchart Period 1
Period 1
Visit Number/Treatment 
Week)a
1
2
3 / (1 wk)
9 / (17 wk)
15 / (33 wk)
4 / (2 wk)a
10 / (18 wk) a
16 / (34 wk) a
5 / (5 wk)
11 / (21 wk)
17 / (37 wk)
6 / (9 wk)
12 / (25 wk)
18 / (41 wk)
7 / (13 
wk)
13/ (29 
wk)
19 / (45 
wk)
8 / (14 wk)a
14 / (30 wk)a
20 / (46 wk)a
Study Day/Visit Windowb
Screening
-42 to -5
Baseline
-4 to -1
1p
113 3
225 3
8 1
120 1
232 1
29 3p
141 3
253 3
57 3
169 3
281 3
85 3
197 3
309 3
92 1
204 1
316 1
Hours Post Dose
Pre
2
Pre
2
Pre
2
Pre
2
Pre
2
Entry/Safety Assessments/Questionnaire
Informed consent/Assentc
X
Demography
X
Medical Historyd
X
Medication History
X
Inclusion/Exclusion Review
X
X
Physical Examinatione
X
X
X
X
X
X
Tanner Stage and Testicular Volumes
X
X
Heightf
X
X
Weightg
X
Xg
X
X
X
X
Vital Signsh
X
X
X
X
X
X
X
X
X
X
X
X
Triplicate ECG
X
X
X
Cardiac MRI (or Echocardiogram)i
X
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Period 1
Visit Number/Treatment 
Week)a
1
2
3 / (1 wk)
9 / (17 wk)
15 / (33 wk)
4 / (2 wk)a
10 / (18 wk) a
16 / (34 wk) a
5 / (5 wk)
11 / (21 wk)
17 / (37 wk)
6 / (9 wk)
12 / (25 wk)
18 / (41 wk)
7 / (13 
wk)
13/ (29 
wk)
19 / (45 
wk)
8 / (14 wk)a
14 / (30 wk)a
20 / (46 wk)a
Study Day/Visit Windowb
Screening
-42 to -5
Baseline
-4 to -1
1p
113 3
225 3
8 1
120 1
232 1
29 3p
141 3
253 3
57 3
169 3
281 3
85 3
197 3
309 3
92 1
204 1
316 1
Hours Post Dose
Pre
2
Pre
2
Pre
2
Pre
2
Pre
2
Clinical Laboratory Testsj
X
X
X
Xa
X
X
X
Xa
Serum Ferritin, Serum Iron, TIBC, % 
Transferrin Saturationj
X
X
X
X
X
X
Hormones (LH, FSH, T4, TSH, 
androstenedione, testosterone)f,s
X
X
Fecal Occult Bloodk
X
X
X
X
X
X
PODCI Questionnaire
X
X
X
X
C-SSRSl
X
X
X
X
X
X
Randomizationm
X
Imaging Assessments
MRI-Liver
X
Xn
MRI-Thigh
Xn
Xn
DXA-Spinei
X
DXA-Whole Body
X
X
X-ray (hand and wrist)s
X
X
Functional Assessments
FVC
Xn
X
Xn
X
4 Stair Climb
Xn
X
Xn
X
Northstar Ambulatory Assessment
Xn
X
Xn
X
Range of Motion
Xn
X
Xn
X
Strength Assessment 
Xn
X
Xn
X
PUL
Xn
X
Xn
X
6MWT
Xn
X
Xn
X
Investigational Product Administration
Investigational Product 
administrationo
X
X
X
X
X
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Period 1
Visit Number/Treatment 
Week)a
1
2
3 / (1 wk)
9 / (17 wk)
15 / (33 wk)
4 / (2 wk)a
10 / (18 wk) a
16 / (34 wk) a
5 / (5 wk)
11 / (21 wk)
17 / (37 wk)
6 / (9 wk)
12 / (25 wk)
18 / (41 wk)
7 / (13 
wk)
13/ (29 
wk)
19 / (45 
wk)
8 / (14 wk)a
14 / (30 wk)a
20 / (46 wk)a
Study Day/Visit Windowb
Screening
-42 to -5
Baseline
-4 to -1
1p
113 3
225 3
8 1
120 1
232 1
29 3p
141 3
253 3
57 3
169 3
281 3
85 3
197 3
309 3
92 1
204 1
316 1
Hours Post Dose
Pre
2
Pre
2
Pre
2
Pre
2
Pre
2
PK/PD/Biomarker/Immunogenicity
PK sampleq
X
X
X
X
Xa
X
X
X
X
X
X
Xa
PD sample (Total GDF-8) q
X
X
X
X
X
X
X
X
X
X
Biomarker Sample Group 1 (Prep 
D1.5)
X
Biomarker Sample Group 2 (Prep 
B1.5, B2.5)j
X
X
X
Biomarker Sample Group 3 (Prep 
R1, Cell-free RNA)
X
Biomarker Sample Liver
X
X
X
X
X
X
X
X
Immunogenicity
X
X
X
X
X
Wellness Phone Checkr
X
X
X
X
X
Infusion Site Reaction monitoring
X
X
X
X
X
X
X
Adverse event monitoring
X






Concomitant medication
X






Abbreviations: = ongoing/continuous monitoring; 6MWT=Six minute walk test; C-SSRS=Columbia Suicide Severity Rating Scale, DXA=Dual-energy x-ray 
absorptiometry; ECG = electrocardiogram; FSH= Follicle stimulating hormone; FVC=Forced vital capacity; GDF-8=growth differentiation factor 8; 
LH= Luteinizing hormone; MRI=magnetic resonance image; PD=Pharmcodynamics, PK=Pharmocokinetics, PODCI=Pediatric Outcomes Data Collection 
Instrument; PUL=Performance of Upper Limb, T4 =thyroxine; TIBC=Total iron binding capacity, TSH=thyroid stimulating hormone.
a.
The first 12 subjects will be required to complete 6 additional visits including Visit 4, 8, 10, 14, 16 and 20 (Day 8, 92, 120, 204, 232 and 316) to provide 
clinical laboratory and PK samples in Period 1.  Subjects enrolled after the first 12 subjects will not be required to complete these additional visits.
b.
Assessments should be conducted on the Study Day within the visit window.  In order to assure consistency in assessment collection, at visits where 
functional assessments and imaging assessments are collected at the same visit, subjects will be required to be assessed over a 2 day period.  Please see 
Section 6 for additional details.
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c.
Informed consent must be provided by the subject’s caregiver (parent or legal guardian).  Subject will be required to provide assent in compliance local 
regulations and IRB requirements.
d.
Medical history will include confirmation by genetic testing of the diagnosis of Duchenne muscular dystrophy (DMD) as obtained from an approved 
laboratory.  Results must confirm the presence of a mutation in the dystrophin gene(s) which is clinically consistent with the diagnosis of DMD.
e.
The physical examination will also include a nose and throat mucosal exam.  
f.
Height and hormone testing should be performed in the morning.
g.
Weight must be collected at each visit prior to dosing. For the dosing on Day 1, the weight from the baseline visit will be used to calculate the dose on 
Day 1.  At subsequent visits after Day 1, either the current visit or the prior month’s weigh may be used to calculate the dose.   
h.
Vital sign evaluations will include supine blood pressure, pulse rate, respiratory rate and oral temperature. At each dosing visit, vital signs will be taken pre 
and post-dosing. The post-dosing vitals will be taken upon completion of the investigational product administration during the 1-hour observational period 
post-dose.  
i.
After the screening assessments are conducted, DXA-spine and cardiac MRI (or echocardiogram) assessments will only be conducted at Visit 21 and 
33 (Day 337 and 673) and Early Withdrawal. If it is not possible to perform cardiac MRI (eg, not available at the site) echocardiogram will be acceptable.  
The same method of cardiac imaging should be used consistently within a single subject. Cardiac MRI with gadolinium should only be performed after all 
other imaging assessments are completed. 
j.
Clinical laboratory tests include hematology, chemistry, gamma-glutamyl transferase (GGT), glutamate dehydrogenase (GLDH), prothrombin time (PT), 
activated partial thromboplastin time (aPTT), creatine kinase, amylase, cardiac troponin I and urinalysis.  Cardiac troponin I will be collected at Baseline, 
Visits 9, 15, 21, 25, 29 and 33 (Days, 113, 225, 337, 449, 561, 673) and EarlyWithdrawal.  The samples for Biomarker Group 2, serum ferritin, serum iron, 
TIBC and % transferrin saturation should be collected following and 8 hour fast.  See Section 7.3 for description on Biospecimen sample collection. 
k.
If a stool sample is unable to be collected during the screening visit, a collection kit and mailing supplies will be sent home and the caregiver will be 
responsible for collection and mailing the sample back to the site.  For all other visits, a stool sample will be collected at home within approximately 1 week 
prior to the scheduled visit.  Note that the collection may fall outside of the visit window.
l.
The “Children’s Baseline/Screening” C-SSRS will be administered at screening.  At all other visits the “Children’s Since Last Visit” assessment will be 
performed.  
m.
Randomization will occur after all screening evaluations and baseline C-SSRs are complete and subjects are confirmed to be eligible to participate in the 
study.  All baseline evaluations should also be completed prior to the randomization, as the weight and 4SC results from baseline are needed at the time of
registration in the randomization system.
n.
At visits when both imaging (MRI-thigh) and functional assessments are being conducted, these assessments should be conducted on separate days.  
Functional assessments should routinely be collected in the morning when the subject is rested and well fed.  The MRI-thigh should routinely be collected at 
approximately the same time of day throughout the study.  Functional assessments must be conducted in the order presented within the schedule of activities.  
Should subjects become non-ambulatory during the study, the 4SC, NSAA and 6MWT will not continue to be collected.  Following the interim analysis (or 
at an earlier time point as determined by the E-DMC upon their review of unblinded data), if the E-DMC determines that monitoring frequency for the liver
is able to be reduced, the liver MRI will then only be conducted at Screening and on Visit 19 and 32 (Days 309 and 645).
o.
Investigational product should be delivered in a 2 hour window -15 or +30 minutes including the flush time.  Subjects are required to be observed for 1 hour 
after the infusion of the investigational product is completed.  If a dosing visit cannot be conducted within the visit window, attempts should be made to 
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bring the subject back for dosing as soon as possible; however the dosing must not occur within 2 weeks prior to the next scheduled dose.  If the subject 
cannot return in this timeframe, the dose should be missed and the next visit should be conducted per the schedule of activities.
p.
Per the local requirements in Japan, all Japanese subjects will be hospitalized for an overnight observation following the first and second treatment on Day 1 
and Day 29.
q.
The window for the PK/PD assessments post dosing at 2 hours is +30 minutes.  If the infusion rate is decreased (following an infusion site reaction) the 
PK/PD assessments should be collected at the time of infusion completion (within a +30 minute window).
r.
Approximately 1 week following each dosing visit, the site will call the caregiver to verify if there are any adverse events which have emerged since dosing.
s.
For subjects who  may be sexually mature at the onset of study (as assessed at the baseline visit) or reach sexual maturity during the trial, as indicated by a 
Tanner Stage V rating, the Tanner Stage, testicular volume, hormone and X-ray (hand and wrist) will no longer required to be collected to assess for signs of 
precocious puberty.  
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Study Flowchart Period 2 and Early Withdrawal
Period 2
Early 
Withdrawal
Visit Number/ (Treatment Week)
21 / (49 wk)
25 / (65 wk)
29 / (81 wk)
22 / (53 wk)
26 / (69 wk)
30 / (85 wk)
23 / (57 wk)
27 / (73 wk)
31 / (89 wk)
24 / (61 wk)
28 / (77 wk)
32 / (93 wk)
33 / (97 wk)
34 / (105 wk)
Study Day/Visit Windowa
337 3
449 3
561 3
365 3
477 3
589 3
393 3
505 3
617 3
421 3
533 3
645 3
673 3
729 3b
Hours Post Dose
Pre
2
Pre
2
Pre
2
Pre
2
Safety Assessments/Questionnaire
Physical Examinationc
X
X
X
X
X
X
Tanner Stage and Testicular Volumep
X
X
X
Heightd
X
X
X
Weighte
X
X
X
X
X
X
Vital Signsf
X
X
X
X
X
X
X
X
X
X
Triplicate ECG
X
X
X
Cardiac MRI or Echocardiogramg
Xg
Xg
X
Clinical Laboratory Testsh
X
X
X
X
X
X
Serum Ferritin, Serum Iron, TIBC, % 
Transferrin Saturationh
X
X
X
X
X
X
Hormones (LH, FSH, T4, TSH, 
androstenedione, testosterone)d,p
X
X
X
Fecal Occult Bloodi
X
X
X
X
X
X
PODCI Questionnaire
X
X
X
X
C-SSRS)j
X
X
X
X
X
X
Imaging Assessments
MRI-Liverl
X
X
MRI-Thighk
X
X
X
DXA-Spineg
Xg
Xg
X
DXA-Whole Body
X
X
X
X-ray (hand and wrist)p
X
X
X
Functional Assessmentsk
FVC
Xk
X
Xk
X
4 Stair Climb
Xk
X
Xk
X
Northstar Ambulatory Assessment
Xk
X
Xk
X
Range of Motion
Xk
X
Xk
X
Strength Assessment 
Xk
X
Xk
X
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Period 2
Early 
Withdrawal
Visit Number/ (Treatment Week)
21 / (49 wk)
25 / (65 wk)
29 / (81 wk)
22 / (53 wk)
26 / (69 wk)
30 / (85 wk)
23 / (57 wk)
27 / (73 wk)
31 / (89 wk)
24 / (61 wk)
28 / (77 wk)
32 / (93 wk)
33 / (97 wk)
34 / (105 wk)
Study Day/Visit Windowa
337 3
449 3
561 3
365 3
477 3
589 3
393 3
505 3
617 3
421 3
533 3
645 3
673 3
729 3b
Hours Post Dose
Pre
2
Pre
2
Pre
2
Pre
2
PUL
Xk
X
Xk
X
6MWT
Xk
X
Xk
X
Investigational Product Administration
Investigational Product administrationm
X
X
X
X
PK/PD/Biomarker/Immunogenicity
PK samplen
X
X
X
X
X
X
X
X
X
PD sample (Total GDF-8)o
X
X
X
X
X
X
X
X
X
Biomarker Sample Group 2(Prep B1.5, B2.5)h
X
X
X
Biomarker Sample Group 3(Prep R1, Cell-free 
RNA)
X
X
X
Biomarker Sample Liver
X
X
X
X
X
X
Immunogenicity
X
X
X
X
X
X
Wellness Phone Checko
X
X
X
X
Infusion Site Reaction monitoring
X
X
X
X
X
X
Adverse event monitoring
X




X
X
Concomitant medication
X




X
X
Abbreviations: = ongoing/continuous monitoring; 6MWT=Six minute walk test; C-SSRS=Columbia Suicide Severity Rating Scale, DXA=Dual-energy x-ray 
absorptiometry;  ECG = electrocardiogram; FSH= Follicle stimulating hormone; FVC=Forced vital capacity; GDF-8=growth differentiation factor 8; 
LH= Luteinizing hormone; MRI=magnetic resonance image; PD-Pharmacodynamics, PK=Pharmacokinetics, PODCI=Pediatric Outcomes Data Collection 
Instrument; PUL=Performance of Upper Limb; T4=thyroxine; TIBC=Total iron binding capacity, TSH=thyroid stimulating hormone.
a.
Assessments should be conducted on the Study Day within the visit window.  In order to assure consistency in assessment collection, at visits where 
functional assessments and imaging assessments are collected at the same visit, subjects will be required to be assessed over a 2 day period. Please see 
Section 6 for additional details.
b.
At the final study Visit 34 (Day 729) any ongoing adverse events and concomitant medications will be reviewed.  This visit can be conducted by phone.
c.
The physical examination will include a nose and throat mucosal exam. 
d.
Height and hormone testing should be performed in the morning.
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e.
Weight must be collected at each visit prior to dosing.  At subsequent visits after Day 1, either the current visit or the prior month’s weight may be used to 
calculate the dose. 
f.
Vital sign evaluations will include supine blood pressure, pulse rate, respiratory rate and oral temperature. At each dosing visit, vital signs will be taken pre 
and post-dosing. The post-dosing vitals will be taken upon completion of the investigational product administration during the 1-hour observational period 
post-dose.   
g.
After the screening assessments are conducted, DXA-spine and cardiac MRI or echocardiogram will only be conducted at Visit 21 and 33 (Day 337 and 673)
and Early Withdrawal. If it is not possible to perform cardiac MRI (eg, not the available at the site) echocardiogram will be acceptable.  The same method of 
cardiac imaging should be used consistently within a single subject. Cardiac MRI with gadolinium should only be performed after all other imaging 
assessments are completed.
h.
Clinical laboratory tests include hematology, chemistry, GGT GLDH, PT, aPTT, creatine kinase, amylase, cardiac troponin I, and urinalysis.  Cardiac 
troponin I will be collected at Baseline, Visits 9, 15, 21, 25, 29 and 33 (Days, 113, 225, 337, 449, 561 673) and Early Withdrawal.  The samples for 
Biomarker Sample Group 2, serum ferritin, serum iron, TIBC and % transferrin saturation should be collected in the morning following an 8 hour fast. See 
Section 7.3 for description on Biospecimen sample collection.
i.
A stool sample will be collected at home within approximately 1 week prior to the scheduled visit. Note that the collection may fall outside of the visit 
window.
j.
The “Children’s Baseline/Screening” C-SSRS will be administered at screening.  At all other visits the “Children’s Since Last Visit” assessment will be 
performed.
k.
At visits when both imaging (MRI-thigh) and functional assessments are being conducted, the assessments should be conducted on separate days.  
Functional assessments should routinely be collected in the morning when subject is rested and well fed.  The MRI-thigh should routinely be collected at 
approximately the same time of day throughout the study. In Period 2, the MRI-thigh will only be conducted at Visit 21 and 33 (Days 337 and 673). 
Functional assessments must be conducted in the order presented within the schedule of activities. Should subjects become non-ambulatory during the 
study, the 4SC, NSAA and 6MWT will not continue to be collected.  
l.
Following the interim analysis (or at an earlier time point as determined by the E-DMC upon their review of unblinded data), if the E-DMC determines that 
the monitoring frequency for liver MRI can be reduced, it will only be conducted at Screening and on Visit 19 and 32 (Days 309 and 645).
m.
Investigational product should be delivered in a 2 hour window -15 or +30 minutes including the flush time.  Subjects are required to be observed for 1 hour 
after the infusion of the investigational product is completed.  If a dosing visit cannot be conducted within the visit window, attempts should be made to 
bring the subject back for dosing as soon as possible; however the dosing must not occur within 2 weeks prior to the next scheduled dose.  If the subject 
cannot return in this timeframe, the dose should be missed and the next visit should be conducted per the schedule of activities. 
n.
The window for the PK/PD assessments post dosing at 2 hours is +30 minutes.  If the infusion rate is decreased (following an infusion site reaction) the 
PK/PD assessments should be collected at the time of infusion completion (within a +30 minute window).  
o.
Approximately 1 week following each dosing visit, the site will call the caregiver to verify if there are any adverse events which have emerged since dosing.
p.
For subjects who may be sexually mature at the onset of the study (as assessed during the baseline visit) or reach sexual maturity during the trial, as indicated
by a Tanner Stage V rating, the Tanner Stage, testicular volume, hormone and X-ray (hand and wrist) will no longer be required to be collected to assess for 
signs of precocious puberty.
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TABLE OF CONTENTS
LIST OF TABLES...................................................................................................................34
APPENDICES .........................................................................................................................34
1. INTRODUCTION ...............................................................................................................35
1.1. Mechanism of Action/Indication.............................................................................35
1.2. Background and Rationale ......................................................................................35
1.2.1. Myostatin Role in Muscle Regulation ........................................................35
1.3. Duchenne Muscular Dystrophy...............................................................................35
1.3.1. PF-06252616...............................................................................................36
1.4. Nonclinical Pharmacodynamics..............................................................................36
1.7. Clinical Experience with PF-06252616 ..................................................................39
1.8. Immunogenicity Risk Assessments.........................................................................40
1.8.2. Immunogenicity Results B5161001 ...........................................................40
1.9. Rationale for Dosage Selection and Method of Administration .............................41
1.10. Study Design Rationale.........................................................................................43
1.11. Anticipated Risks and Safety Monitoring .............................................................44
1.11.6. Radiation...................................................................................................46
1.11.7. Other Risks ...............................................................................................46
1.11.8. Other Safety Monitoring...........................................................................46
1.12. Summary of Risk Benefit......................................................................................47
2. STUDY OBJECTIVES AND ENDPOINTS.......................................................................47
2.1. Objectives................................................................................................................47
2.1.1. Primary Safety and Efficacy.......................................................................47
2.1.2. Secondary ...................................................................................................47
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2.1.3. Exploratory .................................................................................................47
2.2. Endpoints.................................................................................................................48
2.2.1. Primary Safety-Based on Data from Period 1 ............................................48
2.2.2. Primary Efficacy-Based on Data from Period 1.........................................48
2.2.3. Secondary Endpoints-Based on Data from Period 1 and 2.........................48
2.2.3.1. Strength and Function ...............................................................48
2.2.3.2. Pharmacodynamic .....................................................................49
2.2.3.3. Pharmacokinetic........................................................................49
2.2.3.4. Immunogenicity ........................................................................49
2.2.4. Exploratory Endpoint-Based on Data from Period 1 and 2........................50
2.2.4.1. Pharmacologic...........................................................................50
2.2.4.2. Functional Health Status ...........................................................50
2.2.4.3. Long Term Safety-Based on Data from Period 2......................50
2.2.4.4. Duration of Treatment Response-Based on Data from 
Period 2..............................................................................................50
2.2.4.5. Response in a Delayed Treatment Group-Based on Data 
from Period 2.....................................................................................50
3. STUDY DESIGN.................................................................................................................50
3.1. Study Overview.......................................................................................................50
3.2. Duration of Subject Participation............................................................................53
3.3. Approximate Duration of Study..............................................................................53
3.4. Planned Number of Subjects...................................................................................53
3.5. Safety Monitoring, Individual Dose Escalation and the E-DMC............................53
3.5.1. Individual Subject Dose Adjustment and Stopping Rules..........................54
3.5.2. External Data Monitoring Committee (E-DMC)........................................56
4. SUBJECT SELECTION......................................................................................................57
4.1. Inclusion Criteria.....................................................................................................58
4.2. Exclusion Criteria....................................................................................................59
4.3. Randomization Criteria ...........................................................................................61
4.3.1. Screen Failures............................................................................................61
4.4. Lifestyle Guidelines ................................................................................................61
4.4.1. Meals and Dietary Restrictions...................................................................61
4.4.2. Activity .......................................................................................................62
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4.4.3. Contraception..............................................................................................62
4.5. Caregiver(s).............................................................................................................63
4.6. Sponsor’s Qualified Medical Personnel..................................................................63
4.7. Rater Qualifications.................................................................................................64
4.7.1. Columbia-Suicide Severity Rating Scale (C-SSRS)...................................64
4.7.2. Tanner Stage ...............................................................................................64
4.7.3. Clinical Evaluators......................................................................................64
5. STUDY TREATMENTS.....................................................................................................65
5.1. Allocation to Treatment ..........................................................................................66
5.2. Blinding of Site Personnel.......................................................................................67
5.3. Blinding of Sponsor ................................................................................................67
5.4. Breaking the Blind ..................................................................................................67
5.5. Compliance..............................................................................................................68
5.6. Drug Supplies..........................................................................................................68
5.6.1. Dosage Form(s) and Packaging..................................................................68
5.6.2. Preparation and Dispensing........................................................................69
5.7. Investigational Product Administration ..................................................................69
5.8. Investigational Product Storage ..............................................................................70
5.9. Investigational Product Accountability...................................................................71
5.9.1. Destruction of Investigational Product Supplies ........................................71
5.10. Concomitant Treatment(s).....................................................................................71
5.10.1. Permitted Therapies..................................................................................72
5.10.2. Prohibited Therapies.................................................................................72
5.10.3. Rescue Medication....................................................................................73
6. STUDY PROCEDURES .....................................................................................................73
6.1. Visit 1 (Screening Day -42 to -5)............................................................................74
6.1.1. Informed Consent/Assent ...........................................................................74
6.2. Visit 2 (Baseline Day -4 up to -1 prior to dosing on Day 1)...................................76
6.3. Visit 3 (Day 1).........................................................................................................77
6.4. Visit 4, 8, 10, 14, 16, 20 (Day 8, 92, 120, 204, 232, 316) Additional PK visits.....78
6.5. Visits 5, 11, 17, 22, 26, 30 (Days 29, 141, 253, 365, 477, 589)..............................79
6.6. Visits 6, 12, 18, 23, 27, 31 (Days 57, 169, 281, 393, 505, 617)..............................80
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6.7. Visits 7, 13, 19, 24, 28, 32 (Days 85, 197, 309, 421, 533, 645)..............................81
6.8. Visits 9, 15, 21, 25, 29 (Days 113, 225, 337, 449, 561)..........................................82
6.9. Visits 33 (Follow-up Day 673)................................................................................84
6.10. Visit 34 (Follow-up Day 729) ...............................................................................86
6.11. Unscheduled Visits................................................................................................86
6.12. Subject Withdrawal...............................................................................................87
6.13. Subject Lost to Follow-Up ....................................................................................90
7. ASSESSMENTS..................................................................................................................90
7.1. Blood Volume .........................................................................................................90
7.2. Safety.......................................................................................................................91
7.2.1. Clinical Laboratory.....................................................................................91
7.2.2. Physical Examinations/Nose and Throat Exam..........................................93
7.2.3. Tanner Stage and Testicular Volume .........................................................93
7.2.4. Vitals...........................................................................................................93
7.2.5. Electrocardiogram (ECG)...........................................................................93
7.2.6. Cardiac MRI/Echocardiogram....................................................................94
7.2.7. Assessment of Suicidal Ideation and Behavior –Columbia Suicide 
Severity Rating Scale (C-SSRS)......................................................................95
7.3. Banked Biospecimens .............................................................................................96
7.3.1. Markers of Drug Response.........................................................................96
7.3.2. Additional Research....................................................................................97
7.4. Pharmacokinetics (Serum for Analysis of PF-06252616).......................................98
7.5. Anti-Drug Antibody (ADA) anti-PF-06252616 and Neutralizing Antibody 
(NAb).........................................................................................................................98
7.6. Pharmacodynamics/Serum for Total GDF-8...........................................................99
7.7. Imaging Assessments ..............................................................................................99
7.7.1. Liver MRI...................................................................................................99
7.7.2. Thigh MRI ................................................................................................100
7.7.3. Duel-energy X-ray Absorptiometry (DXA) and X-ray ............................100
7.7.3.1. DXA ........................................................................................100
7.7.3.2. X-ray........................................................................................101
7.7.3.3. Radiation Exposure .................................................................101
7.7.4. Additional Research with Imaging Assessments......................................101
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7.8. Functional Assessments ........................................................................................101
7.8.1. Forced Vital Capacity (FVC)....................................................................102
7.8.2. 4 Stair Climb (4 SC) .................................................................................102
7.8.3. Northstar Ambulatory Assessment (NSAA) ............................................102
7.8.4. Range of Motion (ROM) ..........................................................................103
7.8.5. Strength Assessment.................................................................................103
7.8.6. Performance of Upper Limb (PUL)..........................................................103
7.8.7. Six Minute Walk Test (6MWT) ...............................................................103
7.9. Triggered Requirements........................................................................................103
7.10. Infusion Site Monitoring .....................................................................................103
7.11. Pediatric Outcomes Data Collection Instrument (PODCI) .................................104
8. ADVERSE EVENT REPORTING....................................................................................104
8.1. Adverse Events......................................................................................................104
8.2. Reporting Period ...................................................................................................104
8.3. Definition of an Adverse Event.............................................................................105
8.4. Medication Errors..................................................................................................105
8.5. Abnormal Test Findings........................................................................................106
8.6. Serious Adverse Events.........................................................................................106
8.6.1. Protocol-Specified Serious Adverse Events.............................................107
8.6.2. Potential Cases of Drug-Induced Liver Injury..........................................107
8.7. Hospitalization ......................................................................................................109
8.8. Severity Assessment..............................................................................................110
8.9. Causality Assessment............................................................................................110
8.10. Exposure During Pregnancy................................................................................110
8.11. Occupational Exposure .......................................................................................112
8.12. Withdrawal Due to Adverse Events (See Also the Section on Subject 
Withdrawal).............................................................................................................112
8.13. Eliciting Adverse Event Information ..................................................................112
8.14. Reporting Requirements......................................................................................112
8.14.1. Serious Adverse Event Reporting Requirements ...................................112
8.14.2. Nonserious Adverse Event Reporting Requirements .............................113
8.14.3. Sponsor’s Reporting Requirements to Regulatory Authorities ..............113
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9. DATA ANALYSIS/STATISTICAL METHODS.............................................................113
9.1. Sample Size Determination...................................................................................113
9.2. Efficacy Analysis ..................................................................................................114
9.2.1. Analysis of the Primary Endpoint.............................................................114
9.2.2. Analysis of the Secondary Endpoints.......................................................115
9.2.2.1. Historic Control.......................................................................115
9.2.3. Analysis of the Exploratory Endpoints.....................................................116
9.2.4. Analysis of Pharmacokinetics...................................................................116
9.2.5. Analysis of Pharmacodynamics................................................................117
9.3. Safety Analysis......................................................................................................118
9.3.1. Vital Signs ................................................................................................118
9.3.2. Electrocardiogram.....................................................................................118
9.3.3. Cardiac MRI/Echocardiogram..................................................................119
9.3.4. Liver MRI.................................................................................................119
9.3.5. Other Safety..............................................................................................119
9.4. Interim Analysis ....................................................................................................119
9.5. Data Monitoring Committee .................................................................................119
10. QUALITY CONTROL AND QUALITY ASSURANCE...............................................120
11. DATA HANDLING AND RECORD KEEPING ...........................................................120
11.1. Case Report Forms/Electronic Data Record .......................................................120
11.2. Record Retention.................................................................................................121
12. ETHICS............................................................................................................................121
12.1. Institutional Review Board (IRB)/Ethics Committee (EC).................................121
12.2. Ethical Conduct of the Study ..............................................................................121
12.3. Subject Information and Consent........................................................................122
12.4. Subject Recruitment ............................................................................................123
12.5. Reporting of Safety Issues and Serious Breaches of the Protocol or ICH 
GCP .........................................................................................................................123
13. DEFINITION OF END OF TRIAL.................................................................................123
13.1. End of Trial in a Member State...........................................................................123
13.2. End of Trial in All Other Participating Countries...............................................123
14. SPONSOR DISCONTINUATION CRITERIA ..............................................................124
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15. PUBLICATION OF STUDY RESULTS........................................................................124
15.1. Communication of Results by Pfizer ..................................................................124
15.2. Publications by Investigators ..............................................................................125
16. REFERENCES ................................................................................................................126
LIST OF TABLES
Table 1.
Escalating Dose Cohorts and Predicted Exposures and Margins Relative to 
Toxicokinetics Limits at Planned PF 06252616 Doses........................................42
Table 2.
Criteria to Determine Dose Adjustment within Individual Subjects....................55
Table 3.
Period 1 Dosing Schedule.....................................................................................65
Table 4.
Period 2 Dosing Schedule.....................................................................................66
APPENDICES
Appendix 1. Columbia-Suicide Severity Rating Scale (C-SSRS), Children’s 
Baseline/Screening .............................................................................................129
Appendix 2. Columbia-Suicide Severity Rating Scale (C-SSRS), Children’s Since Last 
Visit.....................................................................................................................132
Appendix 3. Pediatric Outcomes Data Collection Instrument (PODCI) 
Age 2-10-Completed by Parent ..........................................................................135
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1. INTRODUCTION
1.1. Mechanism of Action/Indication
The investigational product PF-06252616, a humanized anti-myostatin (GDF-8) monoclonal 
antibody that neutralizes myostatin (GDF-8) is in development for the treatment of Duchenne 
muscular dystrophy (DMD) to preserve and/or improve muscle function.  Other potential 
indications for PF-06252616 include other muscular dystrophies, muscle frailty conditions 
such as cancer cachexia and sarcopenia and rehabilitation of muscle strength.
The safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of 
PF-06252616 have been demonstrated in healthy adults following administration of either 
single ascending intravenous (IV) or a subcutaneous (SC) dose(s) and, subsequently, repeat 
IV doses in adult healthy subjects.
Protocol B5161002 is a first-in-patient study with PF-06252616.  This study will provide the 
initial clinical assessment of the safety, efficacy, PK and PD of PF-06252616 following 
repeat IV doses in ambulatory boys with DMD.
Complete information for this compound may be found in the Single Reference Safety 
Document, which for this study is the Investigator’s Brochure. 
1.2. Background and Rationale
1.2.1. Myostatin Role in Muscle Regulation
Myostatin or growth and differentiation factor 8 (GDF-8) is a member of the bone 
morphogenetic protein transforming growth factor-(BMP/TGF) superfamily of secreted 
differentiation factors (McNally, 2004).23  The muscle specific negative regulator role of 
GDF-8 is well conserved between zebrafish, dogs, cattle, mice and humans.  GDF-8 has been 
best studied in skeletal muscle where GDF-8 -/- mice possess muscles that are 100% to 
200% larger than wild type controls due to a combination of muscle fiber hyperplasia and 
hypertrophy (McPherron et al, 1997).24  Despite having increased skeletal muscle and 
decreased fat, the GDF-8 knockout mice appear to be normal and healthy.  Consistent with 
its role in mice, genetic loss of myostatin is associated with increased muscle mass in many 
different species (McNally, 2004).23  One case of a human has been reported with a 
homozygous mutation of the GDF-8 gene, associated with an absence of GDF-8 protein, 
increased muscle strength and, by age 4, no apparent untoward health effects (Schuelke et al, 
2004).27  Pharmacologic inhibition of GDF-8 activity in rodents results in increased muscle 
mass and improved muscle function in both normal and dystrophic animals (Bradley et al, 
2008).3 Given its effect on skeletal muscle and the absence of abnormality in knockout mice, 
GDF-8 represents an attractive target for diseases associated with muscle loss.
1.3. Duchenne Muscular Dystrophy
DMD is the most frequently inherited neuromuscular disease, and predominantly affects 
boys.  It is an X-linked muscular dystrophy caused by a mutation at Xp21 in the gene coding 
for the protein dystrophin (Bushby et al, 2010; Manzur et al, 2008)4,12 which is absent from 
the muscle of boys with DMD.  DMD is the most severe of all muscular dystrophies and is 
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characterized by skeletal and cardiac muscle degeneration.  Boys with DMD are 
phenotypically unremarkable at birth; onset of symptoms usually occurs around two to three 
years of age.  Most boys lose the ability to walk between the ages of 10 and 14 (Lamperti & 
Moggio, 2010).11  Progressive cardiac problems manifest in the second decade.  Death occurs 
in the late teens or early twenties (Manzur et al, 2008).12  Although girls don’t usually 
experience the full effects of DMD or the milder Becker muscular dystrophy a minority of 
females with the mutation are manifesting carriers, who have a mild form of the disorder 
(Lamperti & Moggio, 2010).11
There is no specific approved treatment that can stop or reverse the progression of DMD.  
Disease management consists primarily of supportive care which ranges from physical 
therapy to maximize function and minimize muscle contractures, to orthotics, tendon release 
surgery (which provides temporary benefit as contractures will redevelop), use of wheel chair 
(usually by age 12), surgical correction of scoliosis (Manzur et al, 2008)12 and use of 
respiratory care including various forms of assisted ventilation (including tracheotomy).  
Respiratory infections may be treated with antibiotics.  Death from pneumonia or cardiac 
involvement in late teens or early twenties is commonly observed in these patients.
A key therapeutic goal is to make DMD symptoms into milder Becker muscular dystrophy 
symptoms, but there is no satisfactory symptomatic or disease-modifying treatment at 
present.  Only limited and inadequate approaches such as chronic glucocorticoid use are 
currently available.  Thus, glucocorticoid off-label use in DMD may improve muscle strength 
for a period of time and perhaps delay the course of the disease, (Mendell et al, 1989; 
Bonifati et al, 2000),25,2 but glucocorticoid use is associated with well-known adverse events 
such as weight gain and broad hypothalamic-pituitary-adrenal axis effects.
1.3.1. PF-06252616
PF-06252616, also referred to as Anti-Myostatin, is a humanized recombinant antibody 
immunoglobulin G1 (IgG1) that neutralizes GDF-8 (myostatin).  PF-06252616 was 
developed by humanization of a mouse monoclonal antibody, designated mRK35, generated 
by immunizing GDF-8 knockout mice with recombinant GDF-8 and isolating monoclonal 
antibodies by splenic fusion using standard hybridoma methodology.  The substitution of 
specific amino acid residues in the Fc region of PF-06252616 has reduced the effector 
functions of the molecule.  The humanized recombinant antibody has a human kappa 
constant domain and a human IgG1 constant domain with 3 mutations to reduce potential 
effector function.  PF-06252616 investigational drug product is supplied as a lyophilized 
sterile powder for solution for injection in a single use vial.  The vials will be reconstituted 
with sterile water for injection (SWFI).  The reconstituted PF-06252616 drug product is clear 
to slightly opalescent and colorless to slightly colored in appearance.
1.4. Nonclinical Pharmacodynamics
Initial studies in mouse demonstrated that mRK35 was superior to a previous anti-myostatin
monoclonal antibody, MYO-029, which prompted humanization of the antibody 
(PF-06252616).  Administration of PF-06252616 to naïve and dystrophic mdx mice resulted 
in increased muscle mass and function.  Subsequent studies demonstrated that PF-06252616 
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could significantly increase lean mass and muscle volume in nonhuman primates (NHP) in a 
dose-dependent manner.  In one NHP study, the animals were monitored during a washout 
period following the last dose, which showed the muscle that accrued during the study was 
maintained for several weeks after the last dose.  Collectively the pharmacology data show 
that muscle anabolic activity of PF-06252616 has been observed in all studies, in both mice 
and NHP.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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1.7. Clinical Experience with PF-06252616
The clinical program for PF-06252616 was initiated in June 2012 with a Phase 1 first in 
human, randomized, double-blind (sponsor and pharmacist unblinded), placebo-controlled 
study (B5161001) evaluating the safety, tolerability, PK, PD, and pharmacologic (anabolic) 
effects of escalating single doses of PF-06252616 in healthy adult subjects.  The study
completed enrollment with 73 subjects at a single site.  Doses of 1, 3, 10, 20, and 40 mg/kg 
administered by IV and 3 mg/kg administered by SC, or placebo were studied.  In addition, a 
repeat IV administration of PF-06252616 10 mg/kg at 2 week intervals over a 28-day 
treatment period was investigated.  Safety was demonstrated at all dose levels and there were 
no dose-related trends in frequency of reported treatment emergent adverse events.
PF-06252616 serum concentrations in Study B5161001 were measured using a validated 
enzyme-linked immunosorbent assay (ELISA) method.  The PK serum profiles following the 
single and repeat dose administrations were analyzed.  Following either single or repeat IV 
infused doses, peak concentrations were generally observed within 2 hours after the end of 
infusion (median Tmax was 4 hours after the start of the 2-hour infusion). Concentrations 
declined relatively rapidly for the first 1 to 2 weeks and more slowly thereafter over a period 
of months.  Following SC administration, Cmax was observed at about 1 week (median Tmax
of 7 days [168 hours]) and concentrations subsequently declined slowly over a period of 
months.  Mean apparent terminal elimination t½ was roughly 2 weeks (14 days) overall but 
appeared to increase with dose, from 12 to 13 days at the lower doses up to 18 to 19 days for 
the higher doses. Serum Cmax generally appears to increase proportionally with dose 
following IV administration of 1 mg/kg to 40 mg/kg. The apparent bioavailability of the 
3 mg/kg SC injection was 61% based on comparison of geometric mean AUCinf values for 
3 mg/kg SC and IV.
The PD activity of PF-06252616 was evaluated in Study B5161001, by measuring total 
serum myostatin levels using a validated liquid chromatography/mass spectrometry (LC/MS) 
method.  Following the PF-06252616 serum concentration levels, total serum 
myostatin levels were noted to be modulated at all dose levels. After single dose 
administration, the median time to maximum total serum myostatin levels was generally 
between 11 and 30 days.  The extent of modulation generally increased between 1 and 
10 mg/kg IV doses and seemed to reach a plateau by the 20 mg/kg IV dose.  In the repeat 
dose cohort, the median myostatin baseline level was 3.1 mg/mL on Day 1 and following 
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10 mg/kg IV dosing, the median myostatin concentration increased to 18.6 ng/mL after the 
third dose.  The median Cmax (myostatin) after 10 mg/kg single and repeat dose were 
24.5 and 24.9 ng/mL respectively. 
One of the secondary objectives of Study B5161001 was to demonstrate proof of mechanism 
(POM) for evidence of a pharmacologic effect based on a percentage change in lean body 
mass (LBM) as measured in dual-energy x-ray absorptiometry (DXA) in the repeat dose 
cohort (10 mg/kg IV every 2 weeks for 1 month).  Per the analysis criteria, the percent 
change in LBM in the repeat dose cohort did not reach significance at any time point 
evaluated.  The criteria were then applied in an exploratory analysis to the magnetic 
resonance imaging (MRI) measurements of thigh muscle volume and T2-mapping of 
measures at each time point.  On the thigh muscle volume measurement, an increase in 
muscle volume at Day 113 was demonstrated, at which time a mean 4.48% difference from 
baseline, relative to placebo, was observed. The T2-mapping analysis further supported the 
observation of an increase of lean muscle in PF-06252616 treated subjects relative to placebo 
in an exploratory analysis. 
Study B5161002 is an ongoing first-in-patient, Phase 2, randomized, 2-period, double-blind, 
placebo-controlled, multiple ascending dose study to evaluate the safety, efficacy, PK and 
PD of PF-0652616 administered to ambulatory boys with DMD. The study was initiated in 
November 2014. Information for this study may be found in the Investigator’s Brochure. 
1.8. Immunogenicity Risk Assessments
 
 
 
 
1.8.2. Immunogenicity Results B5161001
The immunogenicity assessment population included all 53 subjects who received the active 
study drug (PF-06252616) with at least 1 post-treatment anti-drug antibody (ADA) 
determination.  The impact of ADAs and neutralizing antibodies (NAb) on PK and PD were 
also evaluated graphically with no apparent differences in PK and PD profiles between ADA 
positive subjects and ADA negative subjects.
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In subjects receiving active PF-06252616, ADAs were detected early on Day 15 of the study.  
Overall incidence of ADA was noted in 6 out of 53 subjects who received active treatment 
(PF-06252616) in the following cohorts; 1 subject in 1 mg/kg, 10 mg/kg (single IV), 
10 mg/kg (repeat dose) and 20 mg/kg IV dose cohorts; 2 subjects in 3 mg/kg SC dose cohort.  
The confirmed incidence rate was 11.3%.  There were 14 subjects who were considered 
inconclusive and the inconclusive subject-adjusted incidence rate excluding these subjects 
was 15.4% (6 out of 39 subjects).  Samples which tested positive for ADA were further 
tested for NAb. A total of 5 samples from 4 subjects showed NAb titer 1.3 in the following 
cohorts: 1 each in the 1 mg/kg, 10 mg/kg (repeat), 20 mg/kg IV, and 3 mg/kg SC group.  
Although these samples were positive in the NAb assay, all were determined to have 
‘inconclusive’ results for neutralizing activity due to potential interference from 
PF-06252616 levels in these samples.  
In summary, for Study B5161001, there was a confirmed ADA incidence rate of 11.3% but 
without any obvious impact on the PF-06252616 PK or myostatin modulation.
1.9. Rationale for Dosage Selection and Method of Administration
For Study B5161002, 5 mg/kg administered over two hours and every 4 weeks is being 
proposed as the starting dose as it is expected to show median GDF-8 serum coverage over 
80%, and therefore may show pharmacology as well as further provide a safety multiple of 
17 and 28.6 for Cmax and Cav at steady state respectively.  20 mg/kg administered over two 
hours and every 4 weeks is being proposed as the dose that would provide target coverage 
similar to the 10 mg/kg Q 2 week dose in Study B5161001, which produced MRI signal 
changes in healthy volunteers.  40 mg/kg administered over two hours and every 4 weeks is 
being proposed as the highest dose as it will provide additional safety coverage for future 
studies and it maximizes the potential for efficacy, especially considering that the target 
engagement of PF-06252616 in muscles is unclear.  IV was chosen as the route of 
administration to support the large volume of the dose that will be required to obtain the 
targeted GDF-8 coverage as well as for subject adherence.  The frequency of administration 
was chosen as 4 weeks to achieve targeted GDF-8 coverage but also to reduce the burden on 
subject travel to study sites.
To arrive at the above doses and regimens PK and PK/PD approaches were considered using 
the data previously generated within the program.  As prior PF-06252616 PK data has been 
derived in an adult population, a literature review was conducted to determine the CL and Vss
parameters of monoclonal antibodies administered to both an adult and a pediatric 
population.  This meta-analysis suggested that both parameters were similar between the 
adults and children, especially when both populations received a body weight based (mg/kg) 
dosing.  To confirm allometry for the current monoclonal antibody, allometric scaling of 
non-compartmental PK parameters (CL and Vss) determined in mice, rat, monkey and adult 
humans (Study B5161001) were scaled with body weight.  The exponents obtained were 
0.79 and 0.94 for CL and Vss respectively suggesting that PF-06252616 is similar to other 
monoclonal antibodies and that the PK parameters scale allometrically.
Predicted CL and Vss parameters were generated across the population using both the 
allometrically scaled non-compartmental parameters and allometrically scaled (using a fixed 
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0.75 exponent) population PK model; both methods gave similar results where the 5th, 50th
and 95th percentile CL and Vss values using the different methods were <30% different and 
within the normal variability observed for monoclonal antibodies.  These simulations 
considered the range of body weights that are expected in the current study (DMD subjects, 
ages 6 to 10 years old) based on literature values (pooled mean and standard deviations) and 
assessed the appropriateness of administering the same dose (mg/kg) to all subjects.  The 
weight distribution simulation suggested the difference between the lightest (5th percentile of 
age 6) and heaviest (95th percentile of age 10) DMD subject is approximately 36 kg.  
However if dosed per body weight, the corresponding CL values at the above weight 
extremes were approximately 13%.
From a PK/PD consideration, a target mediated drug disposition model (TMDD) was 
developed to simulate PF-06252616 exposures and corresponding GDF-8 coverage.  For 
Study B5161002 PK and GDF-8 simulations, it was assumed that that the weight normalized 
population PK parameters and the GDF-8 binding parameters are similar between healthy 
adult volunteers and DMD subjects 6 to 10 years old.  These parameters were used to 
simulate both the expected PK profile (to compare to toxicology exposure margins) and the 
expected PD profile (considering target coverage in serum).  These simulations suggest that 
5 mg/kg PF-06252616 when administered over a 2-hour infusion duration and every 4 weeks 
provides a median (50th percentile) GDF-8 coverage of approximately 85% with a lower end 
prediction (5th percentile of the trough) of 61% coverage at steady state.  This dose was 
determined to be a suitable starting dose in Study B5161002 as an impact on the 
pharmacology may be expected and there are wide safety margins to the toxicology limits 
(Table 1).  Similarly, simulations suggest that 20 mg/kg PF-06252616 when administered 
over a 2-hour infusion duration and every 4 weeks may provide a median target coverage of 
approximately 95% with the lower end of the prediction (5th percentile of the trough) of 
87% at steady state.  These values are very similar to the estimated GDF-8 coverage for the 
10 mg/kg dose administered every 2 weeks in Study B5161001 which produced a MRI signal 
on Day 113.  Finally, simulations suggest that a 40 mg/kg dose administered every 4 weeks 
will provide median target coverage of approximately 97% with a lower end (5th percentile of 
the trough) of around 93% at steady state.  At the highest dose, it is anticipated that a 2-fold 
safety margin to the toxicology limits will be maintained (Table 1).
Table 1.
Escalating Dose Cohorts and Predicted Exposures and Margins Relative to 
Toxicokinetics Limits at Planned PF 06252616 Doses
IV Dose 
(mg/kg)
Predicted 
Cmax
(g/mL)
Safety margin to 
toxicology limit 
(Cmax)
Predicted 
Cav
Safety margin to 
toxicology limit 
(Cav)
5
158
17
65
28.6
20
598
4.5
265
7.1
40
1214
2.2
550
3.4
a. Toxicology limit set by the NOAEL of 26 week non-human primate juvenile study at 
50 mg/kg [Cmax = 2690 g/mL, Cav,ss=1870 g/mL].
The toxicology AUC168 314,000 g•hr/mL was converted to Cav as follows: 314000 ÷ 168 
= Cav.  The predicted human AUC672 369298 µg•hr/mL was converted to Cav as follows: 
369298 ÷ 672  = 550 g/mL
Cmax = maximum concentration at steady state; Cav = average concentration at steady state.
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1.10. Study Design Rationale
The four stair climb (4SC) has been selected as the primary endpoint for this study based on 
results of prior oral steroid clinical trials in DMD.  The 4SC has been measured for more than 
20 years in DMD, widely used as an outcome in clinical trials, deemed as a reliable measure 
of motor function (Bushby et al 2011; McDonald et al 2013),5,21 can be “bench-marked” by a 
meaningful improvement with steroids (Manzur et al, 2008)13 and is a meaningful indicator 
of DMD boys’ lower limb function in a one year study.
Oral steroids are the only treatment demonstrated in randomized controlled trials to improve 
DMD boys’ strength and function. (Griggs et al 1991; Mendell et al, 1989).7,25  Functional 
improvements were measured as the time required to walk or run 9 meters or to climb 4 stairs 
after six months of daily steroids.  In a pooled analysis of three separate steroid studies, the 
magnitude of six month functional improvement compared to placebo group was larger as 
measured by the stair climb test (-3.69 sec 95% CI [-4.71 to -2.67 sec]) than the walk/run test 
(-2.64 sec 95% CI [-3.70 to -1.58]) (Manzur et al, 2008).13  Clinically, propelling oneself up 
stairs requires more proximal leg strength than walking on a flat surface.  This is supported 
by the natural history of DMD in that boys lose the ability to climb stairs prior to the loss of 
ambulation (Bushby et al, 2011; McDonald et al, 1995).5,18  In addition, there is data to 
support that a prolonged 4SC >8 seconds time is associated with loss of ambulation in 
12 months (McDonald et al, 2013).20  There is a stronger correlation between knee extensor 
strength, a key lower limb muscle to maintain ambulation, and 4SC (r=0.74) than time to 
walk/run (r=0.70) and distance walked in six minutes (r=0.64) (McDonald et al, 2013).21  A 
recent industry sponsored trial from PTC Therapeutics (placebo group) demonstrated that 
DMD boys treated with steroids and 7 years of age demonstrated a mean change of 4.7 sec 
7.5 sec over 12 months (McDonald et al, 2013).20  Therefore, ability to improve time to 
climb 4 stairs in a 12 month study while boys receive standard of care steroid treatment is a 
pertinent functional endpoint.
The six minute walk test (6MWT) has been used as the primary outcome measure in recent 
industry sponsored clinical trials for therapies to improve dystrophin expression in the 
muscle of boys with DMD.  However in these clinical studies as well as in natural history 
studies sizeable variability in the range of 6 minute walk distance (6MWD) change at 
one-year (from -23 to -59 m) as well as a large standard deviation (SD) around the mean 
change (SD 81 to 90 m) were observed in all studies (Mazzone et al, 2013; Goemans et al, 
2013; McDonald et al, 2013).17,8,20  An absolute change in the 6MWD may not be a reliable 
measurement of function in a one-year study of DMD boys for the primary endpoint, and
therefore the 6MWD will be evaluated as a secondary endpoint.
B5161002 is a Phase 2 randomized, 2-period, double-blind, placebo-controlled, multiple 
ascending dose study to evaluate the safety, efficacy, PK and PD of PF-06252616 in 
ambulatory boys with DMD.  The study design is intended to mitigate the bias of treatment 
effect while balancing the opportunity for subjects to receive active drug for a rare and fatal 
disorder.  The study will be conducted in two periods.  In each period the majority of subjects 
will be on active treatment according to the randomization plan (2 active:1 placebo).  In 
Period 2, subjects who received placebo in Period 1 will be assigned active drug.  In order to 
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mitigate the potential heterogeneity in response and because efficacy has not been established 
at any dose level, each subject will have an opportunity to dose escalate to receive all drug 
levels while being monitored for safety.  Based on the publication by McDonald et al 2013,20
subjects who complete a 4SC in >8 seconds may be at higher risk for loss of ambulation in 
the following 12 months.  To balance this potential difference, stratification on the 4 SC at 
baseline will be utilized.
1.11. Anticipated Risks and Safety Monitoring
Complete information for this compound may be found in the Single Reference Safety 
Document, which for this study is the Investigator’s Brochure.
Anticipated risks are based on clinical and toxicology data.
A total of 53 healthy adult subjects have received PF-06252616 in a phase 1 study.  
Forty-two received single IV or SC doses and 11 received a repeat dose (3 doses of 10 mg/kg 
PF-06252616 IV over a 4 week period).  There were no safety findings of concern from this 
study.  In 1 month toxicology studies performed with PF-06252616 in rat and monkey, no 
adverse findings were reported.  Consistent with the pharmacological response anticipated 
from this anti-myostatin monoclonal antibody, effects on skeletal muscle were noted.  In the 
26-week repeat dose toxicity studies in juvenile rats and monkeys, adverse and/or clinically 
relevant findings were noted and provide the basis of the warnings and precautions below.
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
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CCI
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1.11.6. Radiation 
Possible risks related to subject’s undergoing evaluation with DXA and bone age include the 
risk of radiation exposure.  The average effective dose of radiation received for a single DXA 
scan or hand x-ray for bone age may vary due to the instrument and the subject’s body.  The 
expected total radiation dose for 7 whole body DXA exams, 3 spine scans and 7 hand x-rays 
for bone age assessment is not expected to exceed 0.75 mSv.  This is less than 1 year of 
natural background radiation which is approximately 3.0 mSv per year (EHS Radiation Risk; 
Blake et al, 2006).10,1
1.11.7. Other Risks
Possible risks related to the administration of the study drug and/or as a consequence to 
phlebotomy may include hematoma or bruising.
1.11.8. Other Safety Monitoring
Additional safety monitoring will include the parameters of adverse events (AEs), physical 
examination, vital signs, and clinical laboratory parameters (including urinalysis, 
hematology, gamma-glutamyl transferese [GGT], glutamate dyhydrogenase [GLDH],
prothrombin time/activated partial thromboplastin time [PT/aPTT], creatine kinase, amylase, 
and chemistry) and Columbia Suicide Severity Rating Scale (C-SSRS).  Laboratory 
monitoring will also be performed to detect ADA and NAb.
CCI
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1.12. Summary of Risk Benefit
Study B5161002 is the first therapeutic study being conducted in pediatric subjects with 
DMD.  The drug may demonstrate pharmacologic activity in subjects.
In view of the initial clinical evidence of safety and the monitorable nature of key nonclinical 
toxicological findings, data support an acceptable risk profile for PF-06252616 in the current 
study and support a favorable benefit-risk profile in the indication of DMD.  Authorities will 
be kept informed of any additional data (eg, results from clinical studies) which may affect 
the assessment of the risk/benefit ratio for PF-06252616.
2. STUDY OBJECTIVES AND ENDPOINTS
2.1. Objectives
2.1.1. Primary Safety and Efficacy

To determine the safety and tolerability of multiple ascending repeat IV doses of 
PF-06252616 in ambulatory boys with DMD.

To demonstrate the efficacy of treatment with IV doses of PF-06252616 based on an 
observed mean change from baseline on function (4 Stair Climb) as compared to 
placebo following 49 weeks of treatment.
2.1.2. Secondary

To characterize the effects of PF-06252616 on muscle strength and other functional 
assessments compared to placebo.

To evaluate the PD activity of PF-06252616 based on the percent change of muscle 
volume from baseline as compared to placebo.

To evaluate the PD profile of PF-06252616 based on GDF-8 (myostatin) modulation 
in blood.

To characterize the PK profile of PF-06252616.

To evaluate the immunogenicity of PF-06252616.

To characterize the long-term effects following approximately 2-years of treatment 
with PF-06252616 on functional assessments compared to historical control.  

To characterize the effects of PF-06252616 on muscle strength and functional 
assessments compared to placebo in subset of subjects who may demonstrate a rapid 
disease decline and with relatively low variability over a one-year period. 
2.1.3. Exploratory

To evaluate biomarkers that may be informative in demonstrating the pharmacologic 
effect of PF-06252616.
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
To evaluate biomarkers that may be informative for monitoring hepatic liver injury in 
the setting of dystrophic muscle.

To evaluate the Functional Health Status.

To evaluate long term safety of PF-06252616 in subjects treated for >1 year.

To evaluate duration of treatment response following withdrawal and/or continuation 
of treatment for >1 year.

To evaluate response in a delayed treatment group (Sequence Group 3, Period 2).
2.2. Endpoints
2.2.1. Primary Safety-Based on Data from Period 1

Incidence of dose limiting or intolerability treatment related AEs by Week 49.

Incidence, severity and causal relationship of treatment emergent AEs (TEAEs) and 
withdrawals due to TEAEs by Week 49.

Incidence and magnitude of abnormal laboratory findings (clinical laboratory tests 
[hematology, chemistry, GGT, GLDH, PT, aPTT, creatine kinase, amylase, serum 
ferritin, serum iron, Total Iron Binding Capacity (TIBC), % transferrin saturation, 
hormone [luteinizing hormone [LH], follicle stimulating hormone [FSH], thyroxine 
[T4], thyroid stimulating hormone [TSH], fecal occult and urinalysis) by Week 49.

Abnormal and clinically relevant changes in liver MRI by Week 45 and physical 
examinations (including nose and throat mucosal exam and Tanner stage), weight, 
vital signs, ECG, cardiac MRI or echocardiogram measured LVEF (and other 
exploratory cardiac endpoints), DXA-spine (bone mineral density), x-ray (hand and 
wrist for bone age evaluation) and C-SSRS (See Appendix 1 and Appendix 2)
parameters by Week 49.  Cardiac MRI with gadolinium is the preferred method for 
cardiac imaging.  If the subject has a contraindication to gadolinium, cardiac MRI 
without gadolinium will be acceptable.  Echocardiogram may be substituted if it is 
not possible to perform cardiac MRI. 
2.2.2. Primary Efficacy-Based on Data from Period 1

Mean change from baseline on the 4SC as compared to placebo by Week 49.
2.2.3. Secondary Endpoints-Based on Data from Period 1 and 2
2.2.3.1. Strength and Function

Mean change from baseline as compared to placebo on function tests including, 
Forced Vital Capacity (FVC), Northstar Ambulatory Assessment (NSAA), range of 
motion (ROM), Performance of Upper Limb (PUL), 6MWD at Week 17, 33 and 49. 
Mean change from baseline as compared to placebo on the 4 SC at Week 17 and 33.
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
Mean change from baseline as compared to placebo on muscle strength by myometry 
at Week 17, 33 and 49.

In subject randomized to Sequence 1, mean change from baseline as compared to
historical control on functional tests including, 4SC, 6MWD, FVC, NSAA at 
Week 97. 

In a pre-specified subset of subjects who may demonstrate a rapid disease decline and 
with relatively low variability, the mean change from baseline as compared to 
placebo on function tests including, 4SC, FVC, NSAA, PUL, 6MWD at Week 17, 33 
and 49. The definition of this subgroup will be detailed in the Statistical Analysis 
Plan (SAP). 

In a pre-specified subset of subjects who may demonstrate a rapid disease decline, the 
mean change from baseline as compared to placebo on muscle strength at Week 17, 
33 and 49.
2.2.3.2. Pharmacodynamic

Mean percent change as compared to placebo in thigh muscle volume as measured on 
MRI by Week 17, 33 and 49.  Within subject change from baseline in thigh muscle 
volume through Week 97.

Noncompartmental GDF-8 parameters such as AUC(GDF-8), CGDF-8(0), Cmax (GDF-8),
Tmax(GDF-8), Ctrough (GDF-8), and Cav (GDF-8), may be determined.
2.2.3.3. Pharmacokinetic
Noncompartmental PK parameters will be derived from serum PF-06252616 concentration 
data for the following subjects and visits.

All subjects receiving active drug: Cmax, Tmax, and Ctrough for all visits with 
PF-06252616 dosing.

All subjects receiving active drug in Period 1 followed by placebo in Period 2 
(Sequence 2):  terminal t½ for Visit 19 (last dose in Period 1) using concentration 
data from samples collected during placebo treatment in Period 2.

Subjects with additional PK sampling receiving active drug in Period 1:  AUCand 
Cav for Visits 3, 9, and 15 (first dose of each dose escalation level); AUC, Cav, and 
CL for Visits 7, 13, and 19 (last dose of each dose escalation level); for subjects in 
Sequence 2, also Vss for Visit 19.
2.2.3.4. Immunogenicity
Incidence of ADA and NAb development by Week 97.
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2.2.4. Exploratory Endpoint-Based on Data from Period 1 and 2
2.2.4.1. Pharmacologic

Mean percent change from baseline as compared to placebo in lean body mass by 
whole body DXA by Week 17, 33 and 49.  Within subject change from baseline in 
lean body mass through Week 97.

Changes from baseline in muscle quality and fat fraction as compared to placebo as 
measured by T2-mapping and Dixon MRI Week 17, 33 and 49. Within subject 
change from baseline in T2-mapping and Dixon MRI through Week 97. Depending 
on the imaging capabilities at each site, this data may only be collected at a subset of 
sites.

Quantification of changes as measured by blood biomarkers (pharmacogenomic and 
liver).
2.2.4.2. Functional Health Status
Changes from baseline in the Pediatric Data Outcomes Collection Instrument (PODCI) score 
as compared to placebo by Week 17, 33 and 49. Within subject change from baseline in the 
PODCI through Week 97.  See Appendix 3. 
2.2.4.3. Long Term Safety-Based on Data from Period 2
In subjects randomized to Sequence 1, long term safety will be evaluated within subjects as 
compared to baseline for all safety endpoints previously described through Week 97.
2.2.4.4. Duration of Treatment Response-Based on Data from Period 2
In subjects randomized to Sequences 1 and 2, duration of treatment response will be 
evaluated within subjects as compared to baseline for all efficacy (function and strength), 
pharmacologic and PD endpoints previously described through Week 97.
2.2.4.5. Response in a Delayed Treatment Group-Based on Data from Period 2
In subjects randomized to Sequence 3, treatment response will be evaluated within subjects 
as compared to baseline for all efficacy (function and strength), pharmacologic and PD 
endpoints previously described through Week 97.
3. STUDY DESIGN
3.1. Study Overview
This is a Phase 2 randomized, 2-period, double-blind, placebo-controlled, multiple ascending 
dose study to evaluate the safety, efficacy, PK and PD of PF-06252616 administered to 
ambulatory boys diagnosed with DMD.  Three IV infused dose levels will be investigated in
a within subject dose escalating fashion.
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PF-06252616 dose levels:

5 mg/kg

20 mg/kg

40 mg/kg
Depending on safety and PK data availability, alternative dose levels will be available and 
may be evaluated instead of or in addition to the planned dose levels.  In Period 2, dosing 
may be adjusted based on the emerging safety and/or efficacy data.
Approximately 105 eligible subjects will be randomly assigned to 1 of 3 sequence groups and 
receive investigational product for approximately 96 weeks (2 treatment periods of 
approximately 48 weeks each) stratified by their baseline time to complete the 4 SC (either 
or 8 seconds).
Sequence 1 (n=35):
Period 1: Active treatment (PF-06252616) within subject dose escalation (5, 20 and 
40 mg/kg)
Period 2: Active treatment (PF-06252616) at the maximum tolerated dose in Period 1
Sequence 2 (n=35):
Period 1: Active treatment (PF-06252616) within subject dose escalation (5, 20 and 
40 mg/kg)
Period 2: Placebo
Sequence 3 (n=35):
Period 1: Placebo
Period 2: Active treatment (PF-06252616) within subject dose escalation (5, 20 and 
40 mg/kg)
Each dose level will be explored in a dose escalating fashion within subjects, starting with 
the lowest dose.  At each dose level, dosing will be administered over a 2-hour IV infusion 
every 4 weeks for a total of 16 weeks (4 doses).  Dose escalation within a subject will occur 
following review of all available safety data through the planned fourth dose within each 
dose level.  For example, in Period 1, there are three times when individual safety data will 
be reviewed for a determination of dose adjustment, at Week 13, Week 29 and Week 45
(every 4 months). In Period 2, there are two times when individual safety data are reviewed 
for a determination of dose adjustment, at Weeks 61 and 77 (every 4 months). Subjects will 
move from Period 1 to Period 2 without a pause between periods.
Subjects who complete this study through Week 97 may be invited to participate in an 
open-label-extension (OLE) study.  Subjects, who have had a positive test result for ADA at 
any point during the study, may be asked to complete additional immunogenicity testing if 
warranted by other clinical safety findings prior to joining an extension study.
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During the study, additional visits will be required to fully characterize PK and safety when 
subjects would not otherwise be returning for study drug administration.  In order to limit the 
burden of the additional PK/safety assessments, only the first 12 subjects enrolled in the 
study will be asked to complete these additional PK visits.  At each dose level, the first 
12 subjects will be asked to return for testing 1 week after the first dose within each level and 
once again at 1 week after the last dose at each dose level.  The additional PK/safety 
assessments will occur 6 times in Period 1.  No additional visits would be required for these 
subjects in Period 2.  
Exposure from the first 12 subjects will be reviewed to confirm that the exposure in the 
pediatric population is consistent with model predictions from the healthy adult volunteer 
study.  This will occur following at least one dose at the 5 mg/kg dose level and will occur 
again following at least one dose at 20 mg/kg dose level.  Should there be any clinically 
relevant differences in exposure versus those predicted; a dose adjustment may be made as 
agreed with the E-DMC. This analysis will be performed by a group of unblinded Clinical 
Pharmacology scientists not directly involved in the day to day conduct of the study.  It is 
planned that recruitment would continue during this evaluation period.  
The study will remain double-blinded until the time of the primary analysis for safety and 
efficacy (after the last enrolled subject completes 49 weeks).  At that time, a limited number 
of study team members will be unblinded to the treatment assignments.  The sites (with the 
exception of unblinded site personnel eg, the pharmacist) and the subjects will remain 
blinded to their study treatment through the conclusion of the study.
The following is a schematic of the study design.
Note: Sequence 1, Period 2 demonstrates subjects continuing on the maximum tolerated dose from Period 1 for 
each individual subject, as per the dose adjustment criteria (Table 2).  SCRN=Screening, PBO=Placebo, 
W=Weeks
5
mg/kg
20 
mg/kg
40 
mg/kg
40
mg/kg
40 
mg/kg
40
mg/kg
5 
mg/kg
20 
mg/kg
40 
mg/kg
PBO
PBO
PBO
PBO
PBO
PBO
5 
mg/kg
20 
mg/kg
40 
mg/kg
16
16
16
16
16
16
SCRN
SCRN
SCRN
Sequence 
1
Sequence
2
Sequence
3
Period 1 (~48W)
Period 2 (~48W)
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3.2. Duration of Subject Participation
Subjects’ participation will begin during the screening period (up to 6 weeks) followed by 
two dosing periods (48 weeks each) and 2 final study visits (ending 12 weeks after the last 
study dose).  Subjects, who are enrolling in the OLE study, will only be required to return for 
1 final study visit at Week 97.  Subjects will return to the site monthly for study drug 
administration (24 visits) as well as completion of safety and efficacy assessments.
For the first 12 subjects enrolled who are undergoing the additional PK testing, a total of 
34 visits are required.  The remaining subjects will be expected to attend 28 visits.  The total 
time on study for all subjects will be approximately 105 weeks (26 months including 
screening).
In order to assure consistency in assessment collection, visits that include functional 
assessments and imaging assessments (DXA and thigh MRI) will be collected over a 2-day 
period within the study visit window.  In the case where subjects are traveling from a 
distance, the site will offer nearby overnight accommodations.
Per the local requirements in Japan, all Japanese subjects will be hospitalized for an 
overnight observation following the first and second treatment (Day 1 and 29).
3.3. Approximate Duration of Study
The study is estimated to complete in approximately 5 years allowing for 30 months of 
enrollment and 26 months on study.
The end of the study will be the last visit of the last subject for purposes of closing out sites, 
informing the institutional review board/ethics committee (IRB/EC), and ceasing to send 
Council for International Organizations of Medical Sciences (CIOMS) reports.
3.4. Planned Number of Subjects
A minimum of 105 randomized subjects will participate in multiple centers and countries 
worldwide.  In order to assure adequate enrollment, a sufficient number of subjects may be 
screened.  If there are no safety issues, additional subjects may be enrolled prior to the time 
of the interim analysis. These additional subjects may help off-set any unforeseen variability 
that may occur outside the presumed standard deviation for this age group. 
3.5. Safety Monitoring, Individual Dose Escalation and the E-DMC
Individual dose escalation decisions will be conducted for each subject by the Investigator, 
sponsor Medical Monitor and a Designated Reviewer.  This process will occur from time of 
the first subject being enrolled and continue until the time of the IA (or sooner as determined 
by the E-DMC’s review of unblinded data).  At that time, if adequate safety has been 
demonstrated at each dose level as determined by an External Data Monitoring Committee 
(E-DMC), subsequent dose escalation will occur without confirmation of the individual 
safety data prior to dose escalation. 
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From the time of study initiation through completion of the study, the sponsor will conduct 
routine safety monitoring of the blinded data per the safety review plans.  In addition, the 
E-DMC will review unblinded safety data.  The E-DMC may determine if it is necessary to 
close or adjust a dose level within the study or continue with individual level dose escalation 
review.
In the event that the E-DMC determines that adequate safety has been established at each 
dose level (following the IA or sooner), they will also consider if the requirement for liver 
MRI can be reduced to an annual safety assessment (based on normal findings on the liver 
MRI). 
Following the interim analysis, if the E-DMC makes a recommendation to the sponsor 
management to modify or terminate the study based on establishing the efficacy and safety of 
PF-06252616, the sponsor management will review the recommendation with regulatory 
agencies prior to making any changes to the study design, including termination of the study.
3.5.1. Individual Subject Dose Adjustment and Stopping Rules
The individual dose adjustment will be determined by three parties including the 
Investigator, sponsor Medical Monitor and a Designated Reviewer.
The dose adjustment criteria described in Table 2 will be used to determine if the dosing or 
dose level should be:

Escalated to the next dose level

Maintained at the current dose level

Reduced to a lower dose level, or

Stop dosing.
Following the planned fourth dose within each dose level, all available safety data for an 
individual subject will be reviewed to determine the appropriate dose adjustment.  The 
Investigator will confirm the number of doses received within the dose level and review all 
the available safety data along with the sponsor Medical Monitor with the exception of the 
serum iron indices (serum iron, serum ferritin, TIBC, % transferrin saturation) and the liver 
MRI results.  Findings from the serum iron indices and the liver MRI may inadvertently 
unblind the Investigator and the sponsor Medical Monitor to the subject’s treatment 
assignment, therefore results from these tests will not be available to the sites or sponsor 
Medical Monitor for review.  Instead, an unblinded Designated Reviewer will review the
liver MRI results to monitor for potential iron accumulation. The E-DMC will be unblinded 
to the serum iron indices and liver MRI results to provide an ongoing safety review of these 
data.
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The Investigator and sponsor Medical Monitor, if necessary will meet to discuss any safety 
issues and then provide a single recommendation to the unblinded Designated Reviewer who 
will be separately monitoring the liver MRI results.  The Designated Reviewer will collect 
the safety confirmation from the Investigator and sponsor Medical Monitor and apply the 
criteria from Table 2 to determine the dose adjustment action.  The dose adjustment will then 
be applied to the subject’s assigned treatment, accordingly. 
Table 2.
Criteria to Determine Dose Adjustment within Individual Subjects
Dose Adjustment
Decision
Criteria
Increase Dose Level
E-DMC has not closed the next higher dose level and
Subject received 3 doses within a the current dose level and
Investigator and sponsor Medical Monitor indicate that the current dose level is 
safe and
Designated Reviewer indicates that the liver iron content estimate as 
determined by R2* value is within the normal rangea,d.
Maintain Dose Level
E-DMC indicates that the next higher dose level is closed and/or
Subject received <3 doses received within a dose level and
Investigator and sponsor Medical Monitor indicate that the current dose level is 
safe and
Designated Reviewer indicates that the liver iron content estimate as 
determined by R2* is in the normal rangea,d. 
Reduce Dose Level
E-DMC indicates that the current dose level is closed and the subject is not at 
the lowest dose level or
Subject is not at the lowest dose level and
Investigator and sponsor Medical Monitor indicate that the current dose is safe 
and
Designated Reviewer indicates that the liver iron content estimate as 
determined by R2* value is above the normal range b,d. 
Stop Dosing
E-DMC indicates that the current dose level is closed and the subject is at the 
lowest dose level or
Investigator and sponsor Medical Monitor indicate that the current dose is not
safe or
Designated Reviewer indicates that the liver iron content estimate as 
determined by R2* value is above the normal range b,d and the subject is at the 
lowest dose level or
Designated Reviewer indicates that the liver iron content estimate as 
determined by R2* value is within mild overload rangec,d. 
a. R2* normal range is 75 Hz at 1.5 T or R2*139 Hz at 3.0 T
b. R2* above normal range is >75 Hz and 190 Hz at 1.5 T or R2* is >139 Hz and 369 Hz at 3.0 T
c. R2* mild overload range is R2* >190 Hz at 1.5 T or R2* >369 Hz at 3.0 T
d. Storey et al, 2007; Wood et al, 2005; Hankins et al, 2009]).28,29,9
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In order to maintain the treatment blind, all subjects regardless of treatment assignment will 
undergo review for dose adjustment. Subjects who are receiving placebo will have the 
decision criteria applied, as if they are at the lowest dose level.  
The results of the dose adjustment decision (increase, maintain or reduce) will not be 
communicated to the investigator or sponsor medical monitor at any time.
If the Designated Reviewer determines that the subject must stop dosing, he/she will notify 
the sponsor Medical Monitor who will be responsible for informing the Investigator.  In this 
case, the Designated Reviewer may provide the results of the liver MRI (or iron indices) to 
the sponsor Medical Monitor.  The treatment assignment however, will not be provided.
If dosing is stopped, subjects will continue to be followed for resolution of the safety finding 
or until a new baseline is established.  At any time during the study, either the Investigator 
and/or sponsor Medical Monitor may determine a safety issue has occurred and it is in the 
best interest of the subject to stop dosing.  In this case, the sponsor Medical Monitor may not 
overrule the Investigator’s decision, nor will the Investigator overrule the sponsor Medical 
Monitor’s decision.
If the E-DMC determines that a dose level should be closed, following their unblinded 
review of all safety data, no other subjects will be escalated to that dose level.  Subjects who 
are currently dosing within that dose level will be advised by the E-DMC to reduce their dose 
level.  
Subjects in Sequence 2, Period 2, and Sequence 3 Period 1 (who are assigned to placebo), 
will have dosing terminated should they meet any of the criteria described in Table 2 for
“Stop Dosing”.  
Subjects in Sequence 1 will be treated with their maximum tolerated dose level from Period 1 
when they enter Period 2. They will not be escalated to additional higher dose levels in 
Period 2.  For example, if in Period 1, a subject’s maximum tolerated dose is 20 mg/kg, they 
will not be escalated up to 40 mg/kg in Period 2.  Although they will not escalate in Period 2, 
they may have their dose reduced or stop dosing based on the criteria in Table 2.
Subjects, who plan to enroll in the OLE study, will have their maximum tolerated dose from 
study B5161002 be provided by the Designated Reviewer following Week 93 in order to 
continue on the same dose level in the OLE study without unblinding their treatment 
assignment in the B5161002 study.  
3.5.2. External Data Monitoring Committee (E-DMC)
The E-DMC will include experts in the field of neuromuscular diseases and/or statistics.  
Members of the E-DMC will not be Pfizer employees.  The E-DMC will include a Hepatic 
Expert to review any cases of potential liver toxicity. A patient advocate will also be 
included on the E-DMC if an appropriately qualified individual can be identified as agreed 
upon by the E-DMC chairperson. The E-DMC will also include a Cardiology Expert to 
provide expert interpretation of cardiac MRI or echocardiogram results (as needed).  The 
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E-DMC will be responsible for ongoing unblinded efficacy and safety monitoring (including 
the liver MRI and iron indices whose results are blinded to the site and study team) per the 
E-DMC charter from the initiation of the study through the final study visit.  Reviews will 
include aggregate unblinded safety, targeted medical events of special interest including liver 
toxicity, and serious AE data.  The E-DMC may also complete ad hoc safety reviews as 
described in the E-DMC charter.  PK data will be provided to confirm that the exposure in 
the pediatric population does not exceed the predicted PK stopping limits described below.  
Ad hoc PK data may be provided to the E-DMC as requested.  In addition to the safety 
reviews, the E-DMC will review the unblinded study data for futility and efficacy at the time 
of the IA.
Following each data review, the E-DMC will provide a recommendation to the sponsor 
management to continue the study, modify the study and then continue (eg, terminate a dose 
level, reduce the liver MRI assessment to annually, remove the manual process for individual 
dose escalation steps and allow an automated dose-escalation, permit the liver MRI and iron 
indices data to be provided to the site and blinded study team), or stop the study (eg, due to 
safety).  The recommendations made by the E-DMC to alter the conduct of the study will be 
forwarded to the sponsor management for final decision.  The sponsor management will 
forward such decisions, which may include summaries of aggregate analyses of endpoint 
events and of safety data that are not endpoints, to regulatory authorities, as appropriate.  At 
any time the E-DMC may indicate that the limit of safety and/or tolerability has been reached 
and that any of the dose levels will be removed from the study.
The E-DMC will consider the following safety criteria during their safety review:

The number of subjects who have severe AEs or serious AEs in the same organ 
system which are determined to be related to study medication (active treatment, not 
placebo).

The exposure within a dose level which approximately reaches or exceeds the PK 
stopping limits of predicted Cav of 2690 mg/mL and Cmax of 1870 mg/mL (exposures 
obtained at the monkey NOAEL dose of 50 mg/kg).  Modified doses may be 
considered if they are not expected to exceed PK stopping criteria.

Other findings that may indicate that a dose level should be closed.
Details of the type, timing and responsibilities of the E-DMC will be included in the E-DMC 
charter.
4. SUBJECT SELECTION
This study can fulfill its objectives only if appropriate subjects are enrolled.  The following 
eligibility criteria are designed to select subjects for whom participation in the study is
considered appropriate.  All relevant medical and non-medical conditions should be taken 
into consideration when deciding whether a particular subject is suitable for this protocol. 
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4.1. Inclusion Criteria
Subject eligibility should be reviewed and documented by an appropriate member of the 
investigator’s study team before subjects are included in the study.
Subjects must meet all of the following inclusion criteria to be eligible for enrollment into the 
study:
1. Ambulatory boys age 6 to <16 years old (at the time of randomization), diagnosed 
with DMD.  Diagnosis must be confirmed in subject’s medical history and by genetic 
testing obtained during routine clinical care for diagnostic purposes as reported from 
an appropriate regulated laboratory using a clinically validated genetic test (genetic 
testing is not provided by the sponsor).  Results must confirm the presence of a 
mutation in the dystrophin gene(s) which is clinically consistent with the diagnosis of 
DMD.
2. Subjects who are able to perform the 4 stair climb in 0.33 but 1.6 stairs/second at 
screening.*
3. Evidence of a personally signed and dated informed consent and assent (where 
appropriate) document indicating that the subject and a legally acceptable 
representative/parent(s)/legal guardian have been informed of all pertinent aspects of 
the study. 
4. Subjects and their legal guardians who are willing and able to comply with scheduled 
visits, treatment plan, laboratory tests, and other study procedures.  Subjects will be 
required to provide assent in compliance with local regulations and IRB requirements.
5. Subjects must be receiving glucocorticosteroids for a minimum of 6 months prior to 
signing informed consent.  There should be no significant change (>0.2 mg/kg) in 
dosage or dose regimen (not related to body weight change) for at least 3 months 
immediately prior to signing the informed consent and a reasonable expectation that 
dosage and dosing regimen will not change significantly for the duration of the study.
6. Adequate hepatic and renal function on screening laboratory assessments:

GGT upper limit of normal (ULN).

Alkaline phosphatase ULN.

Total Bilirubin ULN.

Serum Albumin LLN.

Serum creatinine ULN.
7. No underlying disposition for iron accumulation on screening laboratory assessments: 
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
Serum Iron 1.2 x ULN.

Serum Ferritin 140 ng/mL.

% Transferrin Saturation 50%.
8. No underlying disposition for bleeding disorder on screening laboratory assessments:

PT/INR 1.25 x ULN.

aPTT 1.25x ULN.

Fecal occult blood is negative. If the fecal occult blood is positive due to known 
pre-exiting medical condition (eg, any cause of rectal bleeding; hemorrhoids, anal 
fissure) that is not considered to be clinically significant by the investigator, the 
subject may be included. 
9. Iron content estimate on the screening liver MRI is within the normal range as 
determined by R2* value (R2*75 Hz at 1.5 T or R2*139 Hz at 3.0 T).
 
 
4.2. Exclusion Criteria
Subjects with any of the following characteristics/conditions will not be included in the 
study:
1. Subjects with known cognitive impairment or behavioral issues that would impede 
the ability to follow instructions.
2. History of major surgical procedure within 6 weeks of signing the informed consent 
or planned surgery during the study.
3. Any injury which may impact functional testing.  Previous injuries must be fully 
healed prior to consenting.  Prior lower limb fractures must be fully healed and at 
least 3 months from injury date.
4. Presence or history of other musculoskeletal or neurologic disease or somatic disorder 
not related to DMD including pulmonary and cardiac disease.
5. Compromised cardiac function (left ventricular ejection fraction <55% as determined 
on a screening cardiac MRI or echocardiogram).  Subjects may be receiving ACE 
(angiotensin-converting-enzyme) inhibitors, blockers, ARB (angiotensin II receptor 
CCI
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blocker) or aldosterone blocker/thiazide diuretic; however they must have initiated 
treatment more than 3 months prior to screening to ensure stable therapy.
6. Evidence or history of clinically significant hematological, renal, endocrine, 
pulmonary, gastrointestinal, cardiovascular (including uncontrolled hypertension), 
hepatic, neurologic, or allergic disease (including drug allergies, but excluding 
untreated, asymptomatic, seasonal allergies at time of dosing).
7. Documented history of iron overload including hemochromatosis, beta thalassemia 
major, beta thalassemia intermedia or hemolytic anemia.
8. Unwilling or unable (eg, metal implants, requires sedation) to undergo examination 
with closed MRI without sedation.
9. Participation in other studies involving investigational drug(s) for a minimum of 
30 days or within 5 half-lives (whichever is longer) prior to signing the informed 
consent and/or during study participation.
10. Current or prior treatment with anti-myostatin, exon skipping, nonsense mutation 
targeted therapies ever or more than 30 days of treatment with utrophin modifiers and 
treatment with utrophin modifiers within 30 days prior to signing the informed 
consent and/or during study participation.
11. Current or prior treatment within the past 3 months with androgens or human growth 
hormone.
12. Current treatment with immunosuppressant therapies (other than glucocorticoid 
steroids), aminoglycosides (eg, gentamicin), multi-vitamins with iron and iron 
supplements and other investigational therapies (including idebenone).
13. History of allergic or anaphylactic reaction to a therapeutic or diagnostic protein or 
additives of this investigational product (histidine, sucrose, edetic acid
[ethylenediaminetetraacetic acid], and polysorbate 80).
14. Have suicidal ideation and behavior associated with actual intent and/or method 
and/or plan and/or action (eg, self-harming behaviors) in the past 6 months based on 
the Columbia-Suicide Severity Rating Scale (C-SSRS Children’s Baseline/Screening 
Appendix 1) or at baseline (C-SSRS Children’s Since Last Visit Appendix 2).
15. Subjects who, in the opinion of the investigator, are biologically capable of having 
children and are sexually active who are unwilling or unable to use a condom to 
prevent potential transfer of exposure to drug through semen; male subjects of 
childbearing potential, with their female partners at risk for pregnancy, who are 
unwilling or unable to use a highly effective method of contraception as outlined in 
this protocol (in addition to the condom to prevent potential transfer of drug through 
semen) for the duration of the study and through completion on final study visit.
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16. Subjects who are investigational site staff members directly involved in the conduct 
of the study and their family members, site staff members otherwise supervised by the 
Investigator, or subjects who are related to Pfizer employees directly involved in the 
conduct of the study.
17. Other severe acute or chronic medical or psychiatric condition or laboratory 
abnormality that may increase the risk associated with study participation or 
investigational product administration or may interfere with the interpretation of 
study results and, in the judgment of the investigator, would make the subject 
inappropriate for entry into this study.
Note: Screening results considered by the investigator to be transient and inconsistent with 
the subject’s clinical condition may be repeated once during the screening period for 
confirmation of eligibility.  The reason for repeating the assessment should be documented.
4.3. Randomization Criteria 
Subjects will be randomized into the study provided they have satisfied all subject selection 
criteria.  During the randomization, the results of the 4 SC from the baseline visit will be 
provided for stratification.  Subjects will be stratified into two groups, those completing the 
4 stair climb in 8 seconds and those completing in >8 seconds. Results from the screening
4 SC (not the baseline 4SC) will be used to determine subject’s eligibility.  The baseline 4SC 
will be used for all analysis.
4.3.1. Screen Failures
Subjects who do not meet the inclusion criteria for the 4SC only will be allowed to re-screen 
one time during the study, while enrollment remains open.  In this case the subject number 
they are assigned at the initial screening will be documented as a screen failure for the 4 SC 
and they will be issued a new subject number for the re-screen.  Re-screen subjects will 
re-consent and depending on the length of time from initial screening to re-screen certain 
screening assessments will need to be repeated.  This information is provided in STUDY 
PROCEDURES Section.  
If subjects are screen failures for any other criteria (other than the 4SC) they will not be re-
screened.  
4.4. Lifestyle Guidelines 
The following guidelines are provided:
4.4.1. Meals and Dietary Restrictions
Subjects should maintain their normal dietary intake throughout the study with the following 
exceptions:

Subjects should abstain from large amounts of caffeine within 24 hours of study 
visits.  Negligible amounts (eg, found in chocolate) are not of concern.
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
Subjects will be asked to fast for at least 8 hours prior to collection of blood to 
evaluate serum ferritin, serum iron, TIBC and % transferrin saturation and Biomarker 
sample Group 2.

Subjects should avoid large meals for at least 2 hours prior to the DXA scan.  Juice, 
water and small snacks may be permitted.  Subjects should be in a state of 
euhydration.  No calcium supplements should be taken within 24 hours of a DXA 
scan.

Two days prior to collection of stool sample for fecal occult testing, whenever 
possible, subjects should refrain from eating red meat, turnips, horseradish, or 
medications containing aspirin or vitamin C.  It is recommended that subjects 
consume small amounts of chicken, canned tuna fish, peanuts, popcorn, bran cereal, 
vegetables and fruit.
4.4.2. Activity
Subjects should be instructed to continue with routine physical therapy including stretching 
or use of orthoses to prevent or minimize contractures or muscle deformities.
Subjects will be instructed to maintain normal activity levels and avoid activities that are not 
part of their normal daily routine within 24 hours of study visits where imaging or functional 
assessments will be performed. 
4.4.3. Contraception
All male subjects who, in the opinion of the investigator, are biologically capable of having 
children and are sexually active and at risk for impregnating a female partner, must agree to 
use with their female partner(s) a highly effective method of contraception consistently and 
correctly for the duration of the active treatment period and through the final study visit.  The 
investigator, in consultation with the subject and/or the subject’s legal guardian, will confirm 
the subject has selected the most appropriate method of contraception for the individual 
subject and his partner from the permitted list of contraception methods (see below) and 
instruct the subject in its consistent and correct use.  The investigator or his/her designee will 
discuss the need to use highly effective contraception consistently and correctly throughout
the study and document such conversation in the subject’s chart.  In addition, the investigator 
will identify the permitted contraception methods as outlined in the protocol.  In addition, the 
investigator or his/her designee will instruct the subject and/or subject’s legal guardian to call 
immediately if the selected birth control method is discontinued or if partner pregnancy is 
known or suspected.
Highly effective methods of contraception are those that, alone or in combination, result in a 
failure rate of less than 1% per year when used consistently and correctly (ie, perfect use) and 
include:
1. Established use of oral, inserted, injected, implanted or transdermal hormonal 
methods of contraception are allowed provided the subject plans to remain on the 
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same treatment throughout the entire study and has been using that hormonal 
contraceptive for an adequate period of time to ensure effectiveness.
2. Correctly placed copper-containing intrauterine device (IUD).
3. Male condom or female condom used WITH a spermicide (ie, foam, gel, film, cream, 
or suppository).  For countries where spermicide is not available, this option is not 
appropriate.
In addition, all sexually active male subjects must agree to prevent potential transfer of and 
exposure to drug through semen to their partners by using a condom consistently and 
correctly, beginning with the first dose of investigational product and continuing through the 
final study visit.
4.5. Caregiver(s)
The parent or legal guardian of the subject will actively participate as caregiver in this study.  
As caregiver, the parent or legal guardian will not only provide informed consent, but will 
also actively participate in the study procedures including completing the PODCI 
questionnaire and being interviewed for the C-SSRS on behalf of the subject.  They will be 
responsible for collection of the fecal sample and providing feedback during the wellness 
calls.  The caregiver will communicate observed safety information to the Investigator or 
designee as appropriate. The investigational site will train the caregiver on instructions to 
collect and/or ship a fecal sample, as needed, and provide other instructions on preparing the 
subject for each study visit. 
A subject’s caregiver(s) must meet all of the following criteria for the subject to be eligible 
for enrollment in the study: 

Is 18 years of age and has demonstrated responsibility as a caregiver through 
monitoring the subject and reporting any observed AEs.

Is available to accompany the subject to the clinic visits.

Can follow instructions.

Is willing and able to give written informed consent.
4.6. Sponsor’s Qualified Medical Personnel
The contact information for the sponsor's appropriately qualified medical personnel for the 
study is documented in the study contact list located in the investigator’s site file.
To facilitate access to appropriately qualified medical personnel on study-related medical 
questions or problems, subjects are provided with a contact card. The contact card contains, 
at a minimum, protocol and investigational compound identifiers, subject study numbers, 
contact information for the investigational site, and contact details for a contact center in the 
event that the investigational site staff cannot be reached to provide advice on a medical 
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question or problem originating from another healthcare professional not involved in the 
subject’s participation in the study. The contact number can also be used by investigational 
staff if they are seeking advice on medical questions or problems; however, it should be used 
only in the event that the established communication pathways between the investigational 
site and the study team are not available. It is therefore intended to augment, but not replace,
the established communication pathways between the investigational site and the study team 
for advice on medical questions or problems that may arise during the study. The contact
number is not intended for use by the subject directly, and if a subject calls that number, he 
or she will be directed back to the investigational site.
4.7. Rater Qualifications 
4.7.1. Columbia-Suicide Severity Rating Scale (C-SSRS)
Clinical staff must be trained to complete the C-SSRS.  This training is provided by the 
sponsor and upon completion a certification will be provided to the trained individual. 
The C-SSRS will be completed by the subject’s care giver/legal guardian throughout the 
study.  
Should a risk of suicide ideation or behavior be identified during completion of the C-SSRS, 
the risk assessment for the C-SSRS must be then performed by a clinically qualified child 
and adolescent mental health provider (MHP).  In the United States, in addition to Child and 
Adolescent Psychiatrists (board certified or board eligible), clinically qualified MHPs include 
the following: (1) general psychiatrists, (2) Psy.D or Ph.D. level Clinical Psychologists, 
(3) licensed Master’s level Clinical Social Workers, or (4) licensed psychiatric Nurse 
Practitioners who have training and experience in the diagnosis and treatment of children and 
adolescents with psychiatric disorders. 
4.7.2. Tanner Stage
Tanner staging assessments to evaluate sexual maturation will be conducted by a physician,
trained physician’s assistant or nurse practitioner as acceptable according to local regulation.  
Training to conduct the Tanner assessment will be provided by the sponsor and upon 
completion, a certification will be provided to the trained individual. 
4.7.3. Clinical Evaluators
Functional assessments including the FVC, 4SC, NSAA, ROM, strength, PUL and 6MWT 
will be conducted by a physiotherapist (or exercise physiologist).  Training on the functional 
assessments and reliability of performance of each assessment specific to this protocol will 
be provided by a master physiotherapist and upon completion, a certification will be provided 
to the individual clinical evaluator. Details of the assessments, training, reliability and 
ongoing quality control are provided in the Functional Assessment manual. 
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5. STUDY TREATMENTS
For the purposes of this study, and per International Conference on Harmonization (ICH)
guidelines, investigational product is defined as a pharmaceutical form of an active 
ingredient or placebo being tested or used as a reference in a clinical trial, including a 
product with a marketing authorization when used or assembled (formulated or packaged) in 
a way different from the approved form, or when used for an unapproved indication, or when 
used to gain further information about an approved use (ICH E6 1.33).
PF-06252616 is incompatible with sodium chloride containing solutions. Therefore, do not 
use Normal Saline (0.9% sodium chloride) or other sodium chloride containing solutions, as 
a diluent or for flushing the infusion line. Dextrose 5% solution is recommended for use 
during flushing to ensure complete delivery of the prepared dosing solution. Refer to the 
Investigational Product Manual and the Administration Card for details regarding the 
preparation and administration of this investigational product.
Subjects will be treated with IV infused PF-06252616 or placebo in this double-blind, 
placebo controlled study. Please refer to the dosage and administration instruction in the 
Investigational Product Manual for complete information on storage, stability, preparation 
and administration of both investigational drug products (PF-06252616 and placebo).
This study is a 3-sequence group, double-blind, placebo controlled, randomized clinical trial.  
Subjects will be randomized to one of 3 sequence groups and will receive treatment on a 
28 day schedule, per the Schedule of Activities.  Each subject will have the opportunity to 
receive a total of four doses of each dose level every four weeks.  The dose will be calculated 
based on the subject weight, which will be obtained at each visit prior to each infusion.  
Either the current weight or the prior month’s weight may be used to provide this calculation 
with the exception of Day 1. At Day 1 the weight from the Baseline visit should be used to 
calculate Day 1 dose.  The following tables depict the dosing schedule in Period 1 and 2 for 
each Sequence group.
Table 3.
Period 1 Dosing Schedule
Dosing Week
1
5
9
13
17
21
25
29
33
37
41
45
Sequence 1
PF-06252616 Dose
5 mg/kg
once every 4 weeks
20 mg/kg
once every 4 weeks
40 mg/kg
once every 4 weeks
Sequence 2
PF-06252616 Dose
5 mg/kg
once every 4 weeks
20 mg/kg
once every 4 weeks
40 mg/kg
once every 4 weeks
Sequence 3
Placebo Dose
0 mg/kg
once every 4 weeks
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Table 4.
Period 2 Dosing Schedule
Dosing Week
49
53
57
61
65
69
73
77
81
85
89
93
Sequence 1
PF-06252616 Dose
40 mg/kg (or maximum tolerated dose per each subject)
once every 4 weeks
Sequence 2
Placebo Dose
0 mg/kg
once every 4 weeks
Sequence 3
PF-06252616 Dose
5 mg/kg
once every 4 weeks
20 mg/kg
once every 4 weeks
40 mg/kg
once every 4 weeks
Note: Sequence 1 in this example shows all subjects tolerating the maximum dose level.
Following demonstration of tolerance at a lower dose, if subjects are unable to tolerate higher 
doses, their dose level may be reduced by a level at the time of dose escalation.  Subjects in 
Sequence 1 will be treated at their maximum tolerated dose level from Period 1 when they 
enter Period 2 and they will not be escalated to additional higher doses during Period 2.  
Subjects in Sequence 3 will receive active drug in Period 2 in accordance with the dose 
adjustment criteria.
Subjects should be administered the investigational product within the visit window 
according to the schedule of activities.  If a dosing visit cannot be conducted within the visit 
window, attempts should be made to bring the subject back for dosing as soon as possible; 
however the dosing must not occur within 2 weeks prior to the next scheduled dose.  If the 
subject cannot return for dosing in this timeframe, the dose should be missed and the next 
visit should be conducted per the Schedule of Activities.
5.1. Allocation to Treatment
Allocation of subjects to the sequence groups (treatment assignment) will proceed through 
the use of an Interactive Response Technology (IRT) System [Interactive Web Response 
(IWR)/Interactive Voice Response (IVR) system] by the unblinded dispensing personnel. 
Note: The IRT is the source of the subject number.  The IRT system will provide the unique 
subject’s study identification (SSID) number at the end of the first IRT subject transaction.  
This number will be retained throughout the study. 
Furthermore, the study site will obtain the randomization number and container number 
assignment from the IRT system.  The randomization number and the date on which the 
randomization number was assigned will be recorded on the case report form (CRF).  Once 
subject screening numbers, container numbers, and randomization numbers have been 
assigned, they cannot be reassigned.
The unblinded dispensing personnel will be required to enter or select information including 
but not limited to their user identification (ID) and password, protocol number, the SSID 
number and the date of birth of the subject.  The unblinded dispenser will be provided with a 
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sequence group assignment and container number when drug is being supplied via the IRT.  
The IRT system will provide a confirmation report containing the subject number and 
container number assigned.  The confirmation report must be retained by the unblinded 
dispenser in the unblinded site files.
There is a 24 hour a day, 365 days a year IRT helpdesk available for any questions or issues.  
The study specific IRT reference manual will provide the contact information and further 
details on the use of the IRT.
5.2. Blinding of Site Personnel
In this observer-blinded study, the study staff preparing and dispensing investigational 
products (PF-06252616 and placebo) will be unblinded, but all other site study personnel, 
including the principal investigator and the subject, will be blinded.  The investigator will 
assign the responsibility of unblinded dispenser to persons who will not participate in the 
evaluation of any study subject.  More than 1 unblinded dispenser must be assigned per site.
A member of the clinic pharmacy should fulfill the role of unblinded dispenser.  Contact 
between the unblinded dispenser and study subjects should be kept to a minimum.  The 
investigator, study coordinator, and any site staff (other than the unblinded dispenser) must 
not be allowed to know the investigational product assigned to any study subject and must 
not be allowed to see the investigational product container contents.
5.3. Blinding of Sponsor
All study team members and laboratory personnel will remain blinded to drug product 
assigned/received throughout the study.  Separate from the study team members, there will 
be an unblinded sponsor-Designated Reviewer who will verify the criteria for dose 
adjustment.  The unblinding process for the purpose of the continuous safety review by 
sponsor personnel not involved in the conduct of the study will be described in the Study 
Blinding Plan. 
5.4. Breaking the Blind
This study is intended to be conducted as double-blind.  The subject, investigator and sponsor 
will be blinded to the randomized study treatments.  The Designate Reviewer (described in 
Section 3.5) and the pharmacists will be identified as unblinded as they will need to 
communicate regarding subject dose level adjustments.  The unblinded pharmacist will 
receive and prepare study drug.  Other unblinded individuals (eg, site monitors, clinical 
pharmacology, E-DMC) will be prospectively identified with their study roles.
A PK/PD unblinding plan approved by the clinical lead, clinical pharmacology lead and 
statistical lead will be in place to describe the procedures to be employed in safeguarding the 
study blind for members of the PF-06252616 study team.  Under this plan a group of 
Statisticians, PK/PD data provider, PK/PD analyst and PK/PD support would be unblinded in 
order to aid in analyzing the PK and PD data as well as to initiate the building of statistical 
models of the PK, as well as exposure/response analysis models and conduct associated 
simulations. 
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The aim of this work will be to facilitate review of PK/PD data for a fuller interpretation of 
the study upon completion (or at appropriate milestones).  This group will not serve on the 
study team while the study is fully blinded prior to the primary analysis being performed.  
The details of the procedures will be described in the PK/PD unblinding Plan for Modeling 
and Simulation for Study B5161002. 
At the initiation of the study, the study site will be instructed on the method for breaking the 
blind.  The method will be an electronic process.  Blinding codes should only be broken in 
emergency situations for reasons of subject safety.  Whenever possible, the investigator or 
sub-investigator consults with a member of the study team prior to breaking the blind.  When 
the blinding code is broken, the reason must be fully documented and entered on the CRF.
The study site pharmacists should not release unblinding information to the other study staff, 
instead the formal IRT procedure should be used.  Aside from such emergent subject safety 
situations, information of study treatment including sequence group, subject dose level and 
randomized study treatment will be kept confidential and will not be released to the 
investigator/study staff until the conclusion of the study.
5.5. Compliance
Study treatment will be administered under the supervision of investigator site personnel.  
Significant medication errors will be considered doses received that are less than 80% or 
greater than 120% of the planned total dose. These will be reported as significant quality 
events. 
5.6. Drug Supplies
5.6.1. Dosage Form(s) and Packaging
PF-06252616 will be provided by Pfizer as a lyophilized powder for injection in single use, 
sterile glass vials. Each vial will be sealed with a coated stopper and an aluminum overseal 
and labeled according to local regulatory requirements.  The drug product must be 
reconstituted with SWFI for IV infusion.  The reconstituted PF-06252616 drug product is a
clear to slightly opalescent solution and colorless to slightly colored in appearance.
The placebo will be provided by Pfizer as a solution for injection.  The placebo is supplied in 
a glass vial sealed with a coated chlorobutyl serum stopper and an aluminum overseal and 
labeled according to local regulatory requirements.
Details of the drug product and its preparation are provided in the dosage and administration 
instructions in the Investigational Product Manual. 
The placebo does not match the active drug product and therefore, the supplies are provided 
as open label vials.  An unblinded pharmacist is required to prepare the investigational 
product.  In order to maintain the blind, a separate area must be used for study drug 
preparation.
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PF-06252616 and placebo will be packaged as open-label supplies.  The external packaging 
(carton) for both products will describe its contents indicating them as active drug product or 
placebo.  Each carton will contain a single vial of study medication or placebo, and each 
carton is identified with a unique container number.  Therefore, it is very important that 
blinded staff do not receive or handle the investigational product.  Each carton will be 
packaged with a tamper-resistant seal.  The sponsor must be notified of any investigational 
product in which the tamper-resistant seal has been broken and this medication should not be 
used.  Further details will be detailed in the Investigational Product Manual.
All ancillary supplies used to prepare and administer doses will be provided by the clinical 
site conducting the study unless otherwise agreed by the sponsor.
5.6.2. Preparation and Dispensing
See the dosage and administration instructions section in the Investigational Product Manual
on how to prepare the investigational product for administration.
Investigational product should be prepared and dispensed by an appropriately qualified and 
trained unblinded site personnel (eg, pharmacist, pharmacist technician) designated to 
participate as staff on the study as allowed by local, state, and institutional guidance.  All 
dosage calculations as well as dose preparation must be performed and checked by a 
minimum of two (2) unblinded clinical site personnel, one of whom must be a licensed health 
care professional.
Unblinded site personnel will receive study specific training on the obligations of the role 
and will sign an agreement that will be maintained in the Site Master File.  No information 
concerning subject treatment assignments will be communicated from the unblinded site
personnel to investigators, site study staff, sponsor’s study staff, or study subjects.
Subject’s body weight will be measured at each time point where study drug is administered 
and used to calculate the dose for that visit.  Either the current or the prior month’s weight 
may be used to provide this calculation with the exception of Day 1. At Day 1 the weight 
from the Baseline visit should be used to calculate Day 1 dose.
Under aseptic conditions, PF-06252616 and placebo should then be prepared according to the 
dosage and administration instructions in the Investigational Product Manual provided by the 
sponsor.
5.7. Investigational Product Administration
Following preparation of the study treatment investigational product (PF-06252616 or 
placebo) by the unblinded site personnel (eg, pharmacist or pharmacist technician), the 
prepared product together with the administration card will be provided to the blinded 
administrator.  The site will take all necessary precautions to maintain the blind of the 
investigator and site personnel including masking the IV bag, the drip chamber and in-line 
filter of infusion set given the potential difference in appearance of the product solution 
(eg, slightly yellow color of PF-06252616 versus clear color of placebo).  If more than one 
subject (participating in either the B5161002 study or the open label extension study) will be 
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infused at the same time in the same room, the use of a curtain or screen between each 
subject with sufficient coverage to block the view of the IV bag/pump between chairs/beds is 
required.  A curtain or screen would not be required if subjects are being infused in a private 
room with no other subjects present.
Topical anesthetics (eg, topical lidocaine at the site of infusion) may be administered to 
subjects, consistent with institutional guidelines.
The IV infusion should be administered by qualified healthcare professionals trained to 
detect any infusion related issues.  Infusion times, rates, any infusion interruptions or 
infusion rate reduction, will be recorded.  The study drug should be infused over a 2-hour 
period (-15 or +30 minutes) where time 0 is the beginning of the infusion and includes the 
flush time. The time to infuse the investigational product and the flush will be recorded. 
Should subjects experience any infusion site reaction during the IV infusion period, the 
administration should be interrupted and supportive care should be provided according to the 
investigator’s standard of care practice (eg, treatment with an antihistamine).  Treatment 
administration may resume if the reaction resolves.  Following the interruption at the 
discretion of the investigator, the infusion rate may be decreased to half the required rate 
(eg, decreased from 50 mL/hr to 25 mL/hr or the duration may be increased from 2 to
4 hours).  If the infusion rate is decreased the window for delivery (-15 or +30 minutes) will 
not be applied. Should the infusion rate be decreased, the PK will be collected per the 
Schedule of Activities.  The duration of the treatment interruption should not exceed the 
limits of in-use shelf-life of the drug product solution per the dosage and administration 
instructions in the Investigational Product Manual.  Consult the Investigational Product 
Manual for detailed instructions regarding study drug preparation, stability and 
administration.  No more than 1 treatment interruption should occur during any single 
infusion.
Subjects should be observed for 1 hour following completion of investigational product 
administration.
5.8. Investigational Product Storage
The unblinded site personnel, (eg, unblinded pharmacist, pharmacy technician) will ensure 
that all investigational products are stored in a secured area with controlled access under 
recommended storage conditions and in accordance with applicable regulatory requirements.
Upon receipt at the study site, the investigational products (PF-06252616 or placebo) must be 
stored in a 2 to 8C temperature-monitored refrigerator and in the original carton, according 
to labeled storage conditions.  The investigational product cannot be used after the expiration 
date on the label.  Please refer to the Investigational Product Manual for complete 
information on storage, handling and stability of the investigational products both prior to 
and following reconstitution.
Storage conditions stated in the single reference safety document (SRSD) (ie, Investigator’s 
Brochure [IB]) will be superseded by the storage conditions stated in the labeling.
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Site systems must be capable of measuring and documenting (for example, via a log), at a 
minimum, daily minimum and maximum temperatures for all site storage locations (as 
applicable, including frozen, refrigerated and/or room temperature products).  This should be 
captured from the time of investigational product receipt throughout the study.  Even for 
continuous monitoring systems, a log or site procedure that ensures active daily evaluation 
for excursions should be available.  The operation of the temperature monitoring device and 
storage unit (for example, refrigerator), as applicable, should be regularly inspected to ensure 
it is maintained in working order.
Any excursions from the product label storage conditions should be reported upon discovery.  
The site should actively pursue options for returning the product to the storage conditions, as 
soon as possible as described in the labeling.  Deviations from the storage requirements, 
including any actions taken, must be documented and reported to the sponsor.
Once an excursion is identified, the investigational product must be quarantined and not used 
until the sponsor provides documentation of permission to use the investigational product.  
Specific details regarding information the site should report for each excursion will be 
provided to the site.  It will not be considered a protocol deviation if the sponsor approves the 
use of the investigational product after the temperature excursion. Use of the investigational 
product prior to sponsor approval will be considered a protocol deviation.
Receipt of materials, door opening and closing, and other routine handling operations where 
the product(s) are briefly out of labeled temperature range are not considered excursions.
The Investigational Product Manual should be referenced for any additional guidance on 
storage conditions and actions to be taken when conditions are outside the specified range.
5.9. Investigational Product Accountability 
The investigator’s site must maintain adequate records documenting the receipt, use, loss, or 
other disposition of the investigational product.
5.9.1. Destruction of Investigational Product Supplies 
The sponsor or designee will provide guidance on the destruction of unused investigational 
product (eg, at the site).  If destruction is authorized to take place at the study site, the 
investigator must ensure that the materials are destroyed in compliance with applicable 
environmental regulations, institutional policy, and any special instructions provided by 
Pfizer, and all destruction must be adequately documented.
5.10. Concomitant Treatment(s)

Subjects will abstain from all prohibited concomitant medications, except if required 
for treatment of AEs.

All concomitant medications taken during the study will be recorded with the 
indication and start and stop dates of administration.  All subjects will be questioned 
about concomitant medications at each visit.
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
Medications taken within 28 days prior to Day 1 will be documented as prior 
medication.  Medications taken from the time of Day 1 will be documented as 
concomitant medications.
5.10.1. Permitted Therapies

Subjects will be required to be receiving glucocorticosteroids (ie, deflazacort, 
prednisolone, and prednisone) for at least 6 months prior to signing the informed 
consent and with no significant changes (>0.2 mg/kg)  in the dose regimen (not 
related to body weight adjustments) for at least 3 months prior to signing the 
informed consent.  During the study, the dose regimen should remain stable unless 
adjustments are required for weight.  If subjects are schedule to receive their 
glucorticodsteroids on the same day as study drug administration, the site may 
instruct subjects to take them in the morning prior to infusion.

Subjects will be permitted to receive ACE inhibitors, blockers, ARB (angiotensin II 
receptor blocker) or aldosterone blocker/thiazide diuretic; however, subjects must 
have initiated treatment more than 3 months prior to screening and plan to remain on
a stable dose during the study.

Supplements such as vitamin D, coenzyme Q10, carnitine, aminoacids (glutamine, 
arginine), anti-inflammatory/anti-oxidants (eg, fish oil, vitamin E, green-tea extract) 
are permitted.  Calcium is permitted but should not be taken with 24 hours prior to a 
DXA scan.  Multi-vitamin without iron is permitted.

Bisphosphonates are permitted.  If they are to be administered at a study visit where 
imaging is also being performed, they should be administered after the imaging is 
complete.  This will help to mitigate any potential interference they may have on the 
imaging.  
5.10.2. Prohibited Therapies
The following are prohibited from the time of signing the informed consent through the final 
study visit.

Immunosuppressant therapy (other than glucocorticosteroids).

Other investigational therapies (including idebenone).

Anti-myostatin, exon skipping, nonsense mutation targeted therapies and utrophin
modifiers.

Aminoglycosides (eg, gentamicin), if required for management of an infection, a
short course of treatment no longer than 14 days is permitted.

Androgens or human growth hormones current and in the past 3 months.

Multi-vitamin with iron or iron supplements. 
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
Sedation prior to undergo imaging assessments.  In the event that a subject becomes 
intolerant to MRI scanning after the screening visit and during the study, the subject 
may be separately consented to be administered sedation in order to complete the 
liver MRI (and/or cardiac MRI) only. 
At the discretion of the sponsor, subjects who receive prohibited therapies may be 
terminated from the study.
5.10.3. Rescue Medication
Should subjects experience an infusion site reaction during the IV infusion period, the 
treatment administration should be paused for the subject and supportive care should be 
provided according to the investigator’s standard practice (eg, treatment with an 
antihistamine).
6. STUDY PROCEDURES 
Every attempt should be made to schedule the visits on the day specified in the Schedule of 
Activities.  In order to provide optimal testing conditions and consistency in endpoint 
measurements, at visits when the functional assessments, imaging and clinical laboratory 
assessments are scheduled to be completed at the same visit, the visit should be completed on 
two days within the visit window and at approximately the same time of day in the order 
described below. 
The Screening and Baseline visit windows are described below.  The visit window for the 
additional PK visits on Day 8, 92, 120, 204, 232 and 316 is 1 Day.  For all other visits, the 
window is 3 days.  The window for the PK/PD assessments post dosing at 2 hours is 
+30 minutes. If the infusion rate is decreased (following an infusion site reaction) the PK/PD 
assessments should be collected at the time of infusion completion and flush (within a 
+30 minute window). Subjects are required to be observed for 1 hour after the administration 
of the investigational product is completed. The post-dosing vital sign will be taken upon 
completion of the investigational product administration during the 1-hour observation 
period.  
At visits when both MRI-thigh and functional assessments are being conducted, these 
assessments should be conducted on separate days.  Functional assessments should routinely 
be collected in the morning when the subject is rested and well-fed.  The MRI-thigh should 
routinely be collected at approximately the same time of day throughout the study.  Should 
subjects become non-ambulatory during the study, the 4SC, NSAA and 6MWT will not 
continue to be collected. 
If a stool sample is unable to be collected during the screening visit, a collection kit and 
mailing supplies will be sent home and the caregiver will be responsible for collection and 
mailing the sample back to the site.  For all other visits, a stool sample will be collected at 
home within approximately 1 week prior to the scheduled visit.  Note that the collection may 
fall outside of the visit window.
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For subjects who may be sexual mature at the onset of the study (as assessed during the 
baseline visit) or reach sexual maturity during the trial, as indicated by a Tanner Stage V 
rating, the Tanner Stage, testicular volume, hormone and X-ray (hand and wrist) will no 
longer be required to be collected during the study to assess for signs of precocious puberty. 
6.1. Visit 1 (Screening Day -42 to -5)
This visit will be conducted over a minimum of 2 days to separate the days when the 
MRI-thigh and functional assessments are conducted. Sites may choose to extend this 
beyond 2 days to accommodate the logistics of completing all testing.  
During screening, subjects and caregiver(s) will be assessed for study eligibility.  All 
screening must be completed and reviewed for subject eligibility before the subject is 
randomized into the study.  Screening tests with results considered by the investigator to be 
transient and inconsistent with the subject’s clinical condition may be repeated once during 
the screening period for confirmation of eligibility.  Imaging based examinations for 
screening must be reviewed for quality by the central imaging vendor before the subject is 
randomized to assure an adequate baseline image has been acquired.  If the image is 
determined to be of poor quality, it will be repeated.  The visit window (Day -42 to -5) for 
screening is to allow for the analysis of laboratory testing, assurance of imaging quality and 
to provide multiple days to perform the assessments in the order described below.  The 
screening assessments should be conducted as consecutive days whenever possible.  
Please note that eligibility confirmation also requires the baseline C-SSRS is completed.  As 
soon as these assessments are completed and a subject’s eligibility has been confirmed, he
may be randomized into the study. 
If a subject becomes a screen failure, and meets the criteria for re-screening as described in 
Section Screen Failures, they must re-consent.  The sponsor must be notified that subject is 
re-screening.  All screening assessments must be repeated with the following exceptions: 
Repeat the following imaging assessment only if more than 6 months have passed since the 
initial screening image was acquired: 

Liver MRI 

Cardiac MRI (or echocardiogram)  

X-ray (hand and wrist).
All other screening assessments must be repeated if the subject is re-screening.  
6.1.1. Informed Consent/Assent
The subject’s parent or legal guardian must sign the informed consent document (ICD) prior 
to initiation of any screening assessments.  The subject will be required to provide assent in 
compliance with local regulations and IRB/EC requirements.
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
Demographics: Information such as date of birth, race, and gender will be collected.

Medical History: Medical history will include confirmation by genetic testing of the 
diagnosis of DMD as obtained as reported from an appropriate regulated laboratory 
using a clinically validated genetic test (genetic testing is not provided by the 
sponsor).  Results must confirm the presence of a mutation in the dystrophin gene(s) 
which is clinically consistent with the diagnosis of DMD.  The mutation type will be 
reported.  Medical history will also be reviewed for any significant medical histories 
and concurrent illnesses that required or are requiring specialist consultation or 
treatment.

Medication History: Complete history will include all prescription or 
nonprescription drugs, and dietary and herbal supplements taken within 28 days prior 
to the planned first dose.  The date of initiation of glucocorticoid steroids will be 
collected. 

Inclusion/Exclusion Criteria: Subjects will be assessed against inclusion and 
exclusion criteria.

Fecal occult blood.  If a stool sample is unable to be collected during the screening 
visit, a collection kit and mailing supplies will be sent home and the caregiver will be 
responsible for collection and mailing the sample back to the site. 

Weight.

Physical Examination: including nose and throat mucosal exam.

Vital Signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.

Triplicate ECG.

Cardiac MRI (with or without gadolinium) or Echocardiogram (the modality used 
to monitor LVEF should be consistent throughout the study for each subject, if 
cardiac MRI with gadolinium is used, the imaging may only performed following all 
other imaging at the study visit).

PODCI questionnaire.

C-SSRS: Children’s Baseline/Screening (Version 6/23/10).
Clinical laboratory testing: 

Fasting blood collection: serum ferritin, serum iron, TIBC and % transferrin 
saturation.

Blood samples for Biomarkers: Group 1, Group 2 (fasting collection), Group 3 
and Liver.
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
Blood samples for hematology, chemistry, GGT, GLDH, PT, aPTT, creatine 
kinase and amylase.

Urine sample for urinalysis.
Imaging assessments:

Fasting Dual-energy x-ray absorptiometry (DXA): whole body and spine.

Magnetic resonance imaging (MRI): thigh and liver.

X-ray: non-dominant hand and wrist.

Functional assessments: All functional assessments in the following order:

FVC.

4SC Used to determine eligibility.

NSAA.

ROM.

Strength assessment.

PUL.

6MWT.
6.2. Visit 2 (Baseline Day -4 up to -1 prior to dosing on Day 1)
This visit may be conducted over 1 or 2 days as determined by the site. 
Clinical laboratory testing: 

Fasting blood collection: serum ferritin, serum iron, TIBC and % transferrin 
saturation

Fasting blood collection for Biomarker: Group 2.

Blood sample for hormones (LH, FSH, T4, TSH, androstenedione, testosterone).
Blood collection for hormones should be done in the morning.

Blood sample for Biomarker: Liver.

Blood sample for hematology, blood chemistry, GGT, GLDH, PT, aPTT, creatine 
kinase, amylase, cardiac troponin I and hormones (LH, FSH, T4, TSH 
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androstenedione, testosterone). Blood collection for hormones should be done in 
the morning.

Blood sample for immunogenicity.

Urine sample for urinalysis.

Weight: The subject’s weight is required when randomizing the subject. 

Height: Height should be measured in the morning.  

Functional Assessments should be assessed in the morning: Must be conducted in 
the following order: FVC, 4SC, NSAA, ROM, strength assessment, PUL, 6MWT.  
Note: The time to complete the 4SC at baseline is required to stratify subjects at the 
time of randomization, however it is the 4SC at screening which will qualify them for 
the study.

Fecal occult blood: Fecal sample is to be collected at home within approximately
1 week prior to scheduled visit.  

Physical Examination: including nose and throat mucosal exam.

Tanner Stage and testicular volume.

Vital signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.

Triplicate ECG.

PODCI questionnaire.

C-SSRS: Children’s Since Last Visit (Version 6/23/10). This evaluation is required 
at baseline to confirm subject’s eligibility.

Inclusion/Exclusion Criteria: Subject eligibility will be confirmed against inclusion 
and exclusion criteria.

Randomization: Randomization will occur after all screening evaluations are 
complete. Subject’s eligibility is based on the screening assessments and the baseline 
C-SSRS.  At the time of randomization, the baseline 4SC and weight are required to 
be entered into the IRT system.  Subjects may be randomized once these assessments 
are complete and subject if determined to be eligible. 
6.3. Visit 3 (Day 1) 
Prior to dosing, the following procedures will be completed:

Blood samples for PK.
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
Blood samples for PD.

Vital signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.
Dosing:

Investigational product administration.
After dosing, the following procedures will be completed:

Vital signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.
Blood samples for:

PK: Collected following the completion of infusion and flush (hour 2).

PD: Collected following the completion of infusion and flush (hour 2).

Infusion site reaction monitoring.

Adverse event (AE) monitoring.

Concomitant medication monitoring.

Wellness phone check: Approximately 1 week following each dosing visit, the site 
will call caregiver to verify if there are any AEs that have emerged since dosing.
6.4. Visit 4, 8, 10, 14, 16, 20 (Day 8, 92, 120, 204, 232, 316) Additional PK visits
The first 12 subjects enrolled in the study will be required to complete 6 additional visits to 
further characterize the PK profile of the study drug.  Subjects enrolled after the first 
12 subjects will not be required to complete these additional visits.
Clinical Laboratory testing:

Blood samples for hematology, chemistry, GGT, GLDH, PT, aPTT, creatine 
kinase and amylase.

Blood sample for Biomarker: Liver.

Blood sample for PK.

Urine sample for urinalysis.

Infusion site reaction monitoring.

AE monitoring.
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
Concomitant medication monitoring.
6.5. Visits 5, 11, 17, 22, 26, 30 (Days 29, 141, 253, 365, 477, 589) 

Fecal occult blood: Fecal sample is to be collected at home within approximately
1 week prior to scheduled visit.

C-SSRS: Children’s Since Last Visit (Version 6/23/10).
Prior to dosing, the following procedures will be completed:
Clinical laboratory sample collection: 

Fasting blood collection: serum ferritin, serum iron, TIBC and % transferrin 
saturation.

Blood sample for Biomarker: Liver.

Blood sample for hematology, chemistry, GGT, GLDH, PT, aPTT, creatine 
kinase and amylase.

Blood sample for immunogenicity.

Urine for urinalysis.

Blood sample for PK.

Blood sample for PD.

Weight: Weight must be collected at each visit prior to dosing. 

Physical Examination, including nose and throat mucosal exam.

Vital signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.
Dosing

Investigational product administration.
After dosing, the following procedures will be completed:

Vital signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.

Blood sample for PK: Collected following the completion of infusion and flush 
(hour 2).

Blood sample for PD: Collected following the completion of infusion and flush 
(hour 2).
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
Infusion site reaction monitoring.

AE monitoring.

Concomitant medication monitoring.

Wellness phone check: Approximately 1 week following each dosing visit, the site 
will call caregiver to verify if there are any AEs that have emerged since dosing.
6.6. Visits 6, 12, 18, 23, 27, 31 (Days 57, 169, 281, 393, 505, 617) 
This visit may be completed on the same day if logistics are permissive.

Fecal occult blood: Fecal sample is to be collected at home within approximately
1 week prior to scheduled visit.

C-SSRS: Children’s Since Last Visit (Version 6/23/10).

PODCI Questionnaire.
Prior to dosing, the following procedures will be completed:
Clinical laboratory testing: 

Fasting blood collection: serum ferritin, serum iron, TIBC and % transferrin 
saturation.

Blood for Biomarker: Liver.

Blood sample for hematology, chemistry, GGT, GLDH, PT, aPTT, creatine 
kinase and amylase.

Blood sample for immunogenicity.

Urine sample for urinalysis. 

Blood sample for PK.

Blood sample for PD.

Weight: Weight must be collected at each visit prior to dosing.

Functional Assessments: Must be conducted in the following order: FVC, 4SC, 
NSAA, ROM, strength assessment, PUL, 6MWT.

Physical Examination, including nose and throat mucosal exam.

Vital signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.
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Dosing

Investigational product administration.
After dosing, the following procedures will be completed:

Vital signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.

Blood sample for PK: Collected following the completion of infusion and flush 
(hour 2).

Blood sample for PD: Collected following the completion of infusion and flush 
(hour 2). 

Infusion site reaction monitoring.

AE monitoring.

Concomitant medication monitoring.

Wellness phone check: Approximately 1 week following each dosing visit, the site 
will call caregiver to verify if there are any AEs that have emerged since dosing.
6.7. Visits 7, 13, 19, 24, 28, 32 (Days 85, 197, 309, 421, 533, 645)  

Fecal occult blood: Fecal sample is to be collected at home within approximately
1 week prior to scheduled visit.

C-SSRS: Children’s Since Last Visit (Version 6/23/10).
Imaging assessments:

MRI: liver (Is able to be conducted at any time during the visit).  If the E-DMC 
determines that the liver MRI monitoring is able to be reduced, it will then only 
be conducted at Visit 19 and 32 (Days 309 and 645). 
Prior to dosing, the following procedures will be completed:
Clinical laboratory testing: 

Fasting blood collection: serum ferritin, serum iron, TIBC, % transferrin 
saturation.

Blood sample for Biomarker: Liver.

Blood sample for hematology, chemistry, GGT, GLDH, PT, aPTT creatine 
kinase and amylase.
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
Blood sample for immunogenicity.

Urine sample for urinalysis.

Blood sample for PK.

Blood sample for PD.

Weight: Weight must be collected at each visit prior to dosing.

Vital signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.

Physical Examination, including nose and throat mucosal exam.
Dosing

Investigational product administration.
After dosing, the following procedures will be completed:

Vital signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.

Blood sample for PK: Collected following the completion of infusion and flush 
(hour 2). 

Blood sample for PD: Collected following completion of infusion and flush (hour 2).

Infusion site reaction monitoring.

AE monitoring.

Concomitant medication monitoring.

Wellness phone check: Approximately 1 week following each dosing visit, the site 
will call caregiver to verify if there are any AEs that have emerged since dosing.
6.8. Visits 9, 15, 21, 25, 29 (Days 113, 225, 337, 449, 561)
A two day visit will be required to complete assessments at this visit. MRI-thigh and 
functional assessments should be collected on separate days. Functional assessments should 
routinely be collected in the morning when the subject is rested and well fed.  The MRI-thigh 
should routinely be collected at approximately the same time of day throughout the study.  

Fecal occult blood: Fecal sample is to be collected at home within approximately
1 week prior to scheduled visit.

C-SSRS: Children’s Since Last Visit (Version 6/23/10).
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
PODCI questionnaire.
Imaging assessments:

DXA: whole body (following 2 hour fast). 

DXA: spine Visit 21 (Day 337) only.

MRI: thigh Visit 9, 15, 21 (Days 113, 225 and 337) only. 

X-ray: non-dominant hand and wrist.

Cardiac MRI (with or without gadolinium) or Echocardiogram Visit 21 (Day 337)
only. The modality used to monitor LVEF should be consistent throughout the study 
for each subject, if cardiac MRI with gadolinium is used, the imaging may only 
performed following all other imaging at the study visit.

Triplicate ECG.

Tanner Stage and testicular volume.

Functional assessments: Must be conducted in the following order: FVC, 4SC, 
NSAA, ROM, strength assessment, PUL, 6MWT.
Prior to dosing, the following procedures will be completed:
Clinical laboratory testing: 

Fasting blood collection: serum ferritin, serum iron, TIBC and % transferrin 
saturation.

Blood sample for hormones (LH, FSH, T4, TSH, androstenedione, testosterone).
Blood collection for hormones should be done in the morning.

Fasting blood collection for Biomarker: Group 2.

Blood sample for Biomarker: Group 3 at Visit 21 (Day 337) only. 

Blood sample Biomarker: Liver.

Blood sample for hematology, chemistry, GGT, GLDH, PT, aPTT, creatine 
kinase, amylase and cardiac Troponin I.

Blood sample for immunogenicity.

Urine sample for urinalysis.
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
Blood sample for PK.

Blood sample for PD.

Weight: Weight must be collected at each visit prior to dosing.

Height: Height should be measured in the morning.

Physical Examination, including nose and throat mucosal exam.

Vital signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.
Dosing

Investigational product administration.
After dosing, the following procedures will be completed:

Blood sample for PK: Collected following the completion of infusion and flush 
(hour 2).

Blood sample for PD: Collected following the completion of infusion and flush 
(hour 2).

Vital signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.

Infusion site reaction monitoring.

AE monitoring.

Concomitant medication monitoring.

Wellness phone check: Approximately 1 week following each dosing visit, the site 
will call caregiver to verify if there are any AEs that have emerged since dosing.
6.9. Visits 33 (Follow-up Day 673)
A two day visit will be required to complete assessments at this visit. MRI-thigh and 
functional assessments should be collected on separate days. Functional assessments should 
routinely be collected in the morning when the subject is rested and well fed.  The MRI-thigh 
should routinely be collected at approximately the same time of day throughout the study.

Fecal occult blood: Fecal sample is to be collected at home within approximately
1 week prior to scheduled visit.

C-SSRS: Children’s Since Last Visit (Version 6/23/10).

PODCI questionnaire.
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Clinical laboratory testing: 

Fasting blood collection: serum ferritin, serum iron, TIBC and % transferrin 
saturation.

Fasting blood collection Biomarker Sample: Group 2 

Blood sample for hormones (LH, FSH, T4, TSH, androstenedione, testosterone).
Blood collection for hormones should be done in the morning.

Blood collection Biomarker: Group 3 and Liver.

Blood sample for hematology, chemistry, GGT, GLDH, PT, aPTT, creatine 
kinase, amylase and cardiac Troponin I.

Blood sample for immunogenicity.

Urine sample for urinalysis.
Imaging assessments:

DXA: whole body (following 2 hour fast).

DXA: spine.

MRI: thigh.

X-ray: non-dominant hand and wrist.

Weight: Weight must be collected at each visit prior to dosing.

Height: Height should be measured in the morning.

Cardiac MRI (with or without gadolinium) or Echocardiogram. The modality used 
to monitor LVEF should be consistent throughout the study for each subject, if 
cardiac MRI with gadolinium is used; the imaging may only performed following all 
other imaging at the study visit.

Triplicate ECG.

Physical Examination, including nose and throat mucosal exam.

Tanner Stage and testicular volume.

Vital signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.
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
Functional assessments: Must be conducted in the following order: FVC, 4SC, 
NSAA, ROM, strength assessment, PUL, 6MWT.

Infusion site reaction monitoring.

AE monitoring.

Concomitant medication monitoring.
6.10. Visit 34 (Follow-up Day 729)
Visit may be conducted by phone.

AE monitoring.

Concomitant medication monitoring.
6.11. Unscheduled Visits
Subjects may return for unscheduled visits as determined by the investigator or the sponsor to 
complete unscheduled safety assessments.  These assessments may include:

Fecal occult blood.

Weight.

Physical Examination, including nose and throat mucosal exam.

Vital Signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.

Triplicate ECG.

Cardiac MRI (with or without gadolinium) or Echocardiogram (the modality 
used to monitor LVEF should be consistent throughout the study for each subject, if 
cardiac MRI with gadolinium is used, the imaging may only performed following all 
other imaging at the study visit).
Clinical laboratory testing: 

Fasting blood collection: serum ferritin, serum iron, TIBC and % transferrin 
saturation.

Blood sample for hematology, chemistry, GGT, PT, aPTT, creatine kinase, 
amylase and cardiac Troponin I.

Blood sample for hormones (LH, FSH, T4, TSH, androstenedione, testosterone). 
Should be collected in the morning.
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
Blood sample for immunogenicity.

Urine sample for urinalysis.

Blood sample for PK.

Blood sample for PD.
Imaging assessments:

MRI: liver.

Infusion site reaction monitoring.

Adverse event (AE) monitoring.

Concomitant medication monitoring.
6.12. Subject Withdrawal
Subjects or subject’s legal guardian who request to discontinue study treatment will remain 
in the study and must continue to be followed for protocol specified follow-up procedures.  
The only exception to this is when a subject/subject’s legal guardian specifically withdraws 
consent for any further contact with him/her or persons previously authorized by the subject 
to provide this information.  Subject/subject’s legal guardian should notify the investigator of 
the decision to withdraw consent from future follow-up in writing, whenever possible.  The 
withdrawal of consent should be explained in detail in the medical records by the 
investigator, as to whether the withdrawal is only from further receipt of investigational 
product only or also from study procedures and/or post treatment study follow-up, and 
entered on the appropriate CRF page.  In the event that vital status (whether the subject is 
alive or dead) is being measured, publicly available information should be used to determine 
vital status only as appropriately directed in accordance with local law.
If the subject withdraws from the study and also withdraws consent for disclosure of future 
information, no further evaluations should be performed and no additional data should be 
collected.  The sponsor may retain and continue to use any data collected before such 
withdrawal of consent.
Subjects may withdraw from the study at any time at their own request, or they may be 
withdrawn at any time at the discretion of the investigator or sponsor for safety or behavioral 
reasons, or the inability of the subject to comply with the protocol-required schedule of study 
visits or procedures at a given study site. 
If a subject does not return for a scheduled visit, every effort should be made to contact the 
subject.  All attempts to contact the subject and information received during contact attempts 
must be documented in the subject’s medical record (see Section 6.13).  In any circumstance, 
every effort should be made to document subject outcome, if possible.  The investigator 
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should inquire about the reason for withdrawal, request that the subject to return for a final 
visit, if applicable, and follow-up with the subject regarding any unresolved AEs. 
It may be appropriate for the subject to return to the clinic for final safety assessments and to 
be questioned regarding their reason for withdrawal.  The following assessments may be 
performed according to the Schedule of Activities: 
Assessments may include:

Fecal occult blood: Fecal sample is to be collected at home within approximately
1 week prior to scheduled visit.
Clinical laboratory sample collection: 

Fasting blood collection: serum ferritin, serum iron, TIBC and % transferrin 
saturation.

Blood sample for hormones (LH, FSH, T4, TSH, androstenedione, testosterone).
Should be collected in the morning.

Biomarker sample collection: Group 2 (fasting collection), Group 3, Liver.

Blood sample for hematology, chemistry, GGT, GLDH, PT, aPTT, creatine 
kinase, amylase and cardiac Troponin I.

Blood sample for immunogenicity.

Urine sample for urinalysis.

Blood sample for PK.

Blood sample for PD.

Height: Height should be measured in the morning.

Weight.

Physical Examination, including nose and throat mucosal exam.

Tanner Stage and testicular volume.

Vital signs: Supine blood pressure, pulse rate, respiratory rate, and oral temperature.

Triplicate ECG.

Cardiac MRI (with or without gadolinium) or Echocardiogram (the modality 
used to monitor LVEF should be consistent throughout the study for each subject, if 
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cardiac MRI with gadolinium is used, the imaging may only performed following all 
other imaging at the study visit).

PODCI questionnaire.

C-SSRS: Children’s Since Last Visit (Version 6/23/10).
Imaging assessments:

DXA: whole body (following 2 hour fast).

DXA: spine.

MRI: thigh.

MRI: liver.

X-ray: non-dominant hand and wrist.

Functional assessments: Must be conducted in the following order: FVC, 4SC, 
NSAA, ROM, strength assessment, PUL, 6MWT.

Infusion site reaction monitoring.

AE monitoring.

Concomitant medication monitoring.
In the event of clinically important treatment-emergent suicidal ideation or suicidal behavior, 
the subject will be withdrawn from the study and will receive the appropriate medical care.  
The Investigator will follow up until the subject’s condition has stabilized.  Additionally, a 
risk assessment or evaluation of suicide risk will be completed by a child and adolescent 
mental health provider as part of the psychiatric evaluation and assessment of subject safety.  
Refer to Section 7, Assessments.  Clinically important suicidality includes but is not limited 
to:
1. Suicidal behavior (with or without intent of suicide or serious self-harm).
2. Determination of “yes” on question 4 (Active Suicidal Ideation with Some Intent or 
Act, Without Specific Plan) for the Suicidal Ideation section of the C-SSRS. 
3. Determination of “yes” on question 5 (Active Suicidal Ideation with Specific Plan 
and Intent) for the Suicidal Ideation section of the C-SSRS.
4. Determination of “yes” on the question of Actual Attempt, Interrupted Attempt, 
Aborted Attempt, or Preparatory Acts or Behavior for Suicidal Behavior section of 
C-SSRS.
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5. Acute suicidality to such a degree that precaution against suicide must be exercised.
6.13. Subject Lost to Follow-Up
All reasonable efforts must be made to locate subjects to determine and report their ongoing
status. This includes follow-up with persons authorized by the subject as noted above. Lost 
to follow-up is defined by the inability to reach the subject after a minimum of 2 documented 
phone calls, faxes, or emails as well as lack of response by the subject to 1 registered mail 
letter. All attempts should be documented in the subject’s medical records. If it is 
determined that the subject has died, the site will use permissible local methods to obtain the 
date and cause of death. If the investigator’s use of a third-party representative to assist in 
the follow-up portion of the study has been included in the subject’s informed consent, then 
the investigator may use a sponsor retained third-party representative to assist site staff with 
obtaining the subject’s contact information or other public vital status data necessary to 
complete the follow-up portion of the study. The site staff and representative will consult 
publicly available sources, such as public health registries and databases, in order to obtain 
updated contact information. If after all attempts, the subject remains lost to follow-up, then 
the last known alive date as determined by the investigator should be reported and 
documented in the subject’s medical records.
7. ASSESSMENTS
Every effort should be made to ensure that the protocol-required tests and procedures are 
completed as described. However, it is anticipated that from time to time there may be 
circumstances, outside of the control of the investigator that may make it unfeasible to 
perform the test. In these cases the investigator will take all steps necessary to ensure the 
safety and well-being of the subject. When a protocol-required test cannot be performed, the 
investigator will document the reason for this and any corrective and preventive actions that 
he or she has taken to ensure that normal processes are adhered to as soon as possible. The 
study team will be informed of these incidents in a timely fashion.  In the event that a subject 
becomes intolerant to MRI scanning after the screening visit and during the study, the subject 
may be separately consented to be administered sedation in order to complete the liver and 
cardiac MRI only. 
Per the sites local standard operating procedures for blood collection, an IV cannula may be 
placed in the contralateral arm (from the arm where the IV infusion is being administered) to
obtain serial blood samples.  Samples should never be drawn from the same arm as the 
investigational product is administered as this will confound the PK results.  Consistent with 
the institutional guidelines, a topical anesthetic (eg, topical lidocaine) may be administered to 
subjects prior to the blood draw.  
7.1. Blood Volume
To minimize the volume of blood collected in this pediatric study, the Center for Disease 
Control and Prevention (CDC) growth chart was used to estimate the lower end weight in a 
healthy boy which would be approximately 15 kg (10th percentile weight).  Based on this 
weight, the total blood volume per month will not exceed approximately 45 mL.
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The following chart provides estimates of the approximate blood volume collected by visit.
Period 
Visit
Total Volume 
(mL) At Each 
Visit
Period 1
Screening
28
Baseline, Day 1
35
Day 8, 92, 120, 204, 232, 316 (Additional PK)
8
Day 29, 57, 85, 141, 169, 197, 253, 281, 309
24
Day 113, 225
35
Total Volume Period 1, including additional PK*
396
Total Volume Period 1, excluding additional PK
347
Period  2
Day 337
47
Day 449, 562
35
Day 365, 393, 421, 477, 505, 533, 589, 617, 645
24
Day 673
35
Total Volume Period 2
366
Early Withdrawal
39
*Additional PK visit to be conducted in the first 12 subjects enrolled. 
7.2. Safety
7.2.1. Clinical Laboratory 
The following safety laboratory tests will be performed at times defined in the Schedule of 
Activities section of this protocol.  Unscheduled clinical labs may be obtained at any time 
during the study to assess any perceived safety concerns.
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Laboratory Tests
Hematology
Chemistry
Urinalysis
Other
Hemoglobin
Hematocrit
RBC count
Platelet count
WBC count
(and 
morphology 
as applicable)
Total 
neutrophils 
(Abs)
Absolute 
neutrophils 
(ANC)
Eosinophils 
(Abs)
Monocytes 
(Abs)
Basophils 
(Abs)
Lymphocytes 
(Abs)
BUN and 
Creatinine
Glucose 
Calcium
Sodium
Potassium
Chloride
Total 
CO2 (Bicarbonate)
AST, ALT
Total Bilirubin
Alkaline 
phosphatase
Uric acid
Albumin
Total protein
Serum Phosphorus
pH
Glucose (qual)
Protein (qual)
Blood (qual)
Ketones
Nitrites
Leukocyte 
esterase
Microscopya
GGT
GLDH
PT
INR
aPTT
Creatine kinase
Amylase
Serum for Liver 
Biomarker 
Cardiac 
Troponin I
Serum Ferritinc
Serum Ironc
Total Iron 
Bindingc
Capacity 
(TIBC)c
Unsaturated 
Binding
capacityc,
% Transferrin 
Saturationc
Hormones (LH, 
FSH, T4 (total 
and free), TSH, 
androstenedione, 
testosterone) d
Fecal Occult
Additional Testsb
AST, ALT 
(repeat)
Total bilirubin 
(repeat)
Albumin (repeat)
Alkaline 
phosphatase 
(repeat)
Direct bilirubin
Indirect bilirubin
Creatine kinase
GGT
GLDH
PT
INR
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a. Only if urine is positive for blood, protein, nitrites or leukocyte esterase.
b. Additional testing for potential Hy's Law cases only.
c. Following an 8 hour overnight fast.
d. Collect blood in the morning for hormone testing. For subjects who may reach sexual 
maturity, hormone testing will no longer be required. 
7.2.2. Physical Examinations/Nose and Throat Exam
Physical examinations may be conducted by a physician, trained physician's assistant, or 
nurse practitioner as acceptable according to local regulation.  The physical examination will 
include head, ears, eyes, nose, mouth, skin, heart and lung examinations, lymph nodes, 
gastrointestinal, musculoskeletal, and neurological systems.  A targeted nose and throat 
mucosal exam will be performed according to the Schedule of Activities to monitor for any 
signs of mucosal telangiectasias. 
Abnormal findings will be further characterized as “clinically significant” or “not clinically 
significant” for the purposes of reporting as adverse events. 
7.2.3. Tanner Stage and Testicular Volume
Tanner Staging will be performed according to the Schedule of Activities to monitor for 
signs of accelerated sexual development.  The physical changes in pubertal development
(genital and pubic hair growth) will be assessed using the system described by Marshall and 
Tanner (Marshall &Tanner 1970).14  In addition to the Tanner staging, a measurement of 
testicular size (volume) using orchidometer beads will be documented. 
For subjects who may reach sexual maturity during the trial, as indicated by a Tanner 
Stage V rating, the Tanner Stage, testicular volume, hormone and X-ray (hand and wrist) will 
no longer be required to be collected to assess for signs of precocious puberty. 
7.2.4. Vitals
Supine blood pressure, pulse rate, respiratory rate and temperature will be measured at times 
specified in Schedule of Activities section of this protocol.  Unscheduled collection times 
will be permitted, as necessary, to ensure appropriate collection of safety data.
Supine blood pressure will be measured with the subject’s arm supported at the level of the 
heart, and recorded to the nearest mm Hg after at least 5 minutes of rest.  Whenever possible, 
the same arm (preferably the dominant arm) should be used throughout the study. 
Wherever possible, the same size blood pressure cuff, which has been properly sized and 
calibrated, will be used to measure blood pressure each time.  The use of automated devices 
for measuring BP and pulse rate are acceptable, although, when done manually, pulse rate 
will be measured in the brachial/radial artery for at least 30 seconds. 
7.2.5. Electrocardiogram (ECG)
ECGs should be collected at times specified in the Schedule of Activities section of this 
protocol.
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All scheduled ECGs should be performed after the subject has rested quietly for at least 
10 minutes in a supine position.
Triplicate 12-lead ECGs will be obtained approximately 2-4 minutes apart; the average of the 
triplicate ECG measurements collected at Baseline (Visit 2), will serve as each subject’s 
time-controlled baseline QTc value. 
To ensure safety of the subjects, a qualified individual at the investigator site will make 
comparisons to baseline measurements.  If the QTc interval is increased by 45 msec from 
the baseline, or an absolute QTc value is 500 msec for any scheduled ECG, then 
2 additional ECGs will be collected, approximately 2-4 minutes apart, to confirm the original 
measurement.  If either of the QTc values from these repeated ECGs remains above the 
threshold value (45 msec from the baseline; or is 500 msec), then a single ECG must be 
repeated at least hourly until QTc values from 2 successive ECGs fall below the threshold 
value that triggered the repeat measurement. 
The QTc interval should be recorded using the QTcF (QTc Fridericia) value in milliseconds. 
In the event that the equipment is not able to provide the QTcF, please use the formula below 
to calculate.  
Formula = QT/((60/HR)^(1/3))
If the average of QTcF values from the triplicate measurements remains above the threshold 
value (45 msec from the baseline; or is 500 msec), then a single ECG must be repeated at 
least hourly until QTc values from 2 successive ECGs fall below the threshold value that 
triggered the repeat measurement.
If QTcF values remain 500 msec (or 45 msec from the baseline) for greater than 4 hours 
(or sooner at the discretion of the investigator); or QTcF intervals get progressively longer, 
the subject should undergo continuous ECG monitoring.  A cardiologist should be consulted 
if QTcF intervals do not return to less than 500 msec (or to <45 msec above the baseline) 
after 8 hours of monitoring (or sooner at the discretion of the investigator).
In some cases, it may be appropriate to repeat abnormal ECGs to rule out improper lead 
placement as contributing to the ECG abnormality.  It is important that leads are placed in the 
same positions each time in order to achieve precise ECG recordings.  If a machine-read 
QTcF value is prolonged, as defined above, repeat measurements may not be necessary if a 
qualified physician’s interpretation determines that the QTcF values are in the acceptable 
range.
7.2.6. Cardiac MRI/Echocardiogram
Cardiac MRI or echocardiograms should be collected at times specified in the Schedule of 
Activities section of this protocol.  The same method of cardiac imaging should be used 
consistently within a single subject.
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Cardiac MRI with gadolinium is the preferred method for cardiac imaging.  When cardiac 
MRI with gadolinium is used, it should only be collected after all imaging required at the 
same visit is performed.  If the subject has a contraindication to gadolinium, cardiac MRI 
without gadolinium will be acceptable. Cardiac MRIs will be read by a central imaging 
vendor and only the results of the left ventricular ejection fraction (LVEF) will be provided 
to sites. Sites will be provided with a scanning and image transmittal guide for collection of 
the cardiac MRI.
If cardiac MRI is utilized, it will be read by a central imaging vendor. 
If it is not possible to perform cardiac MRI (eg, it is not available at the site), echocardiogram 
will be acceptable.  Echocardiogram will be read locally at each site.  To ensure safety of the 
subjects, a qualified individual at the investigator site will evaluate the echocardiogram for
ventricular systolic pressure, left arterial diameter, left ventricular mass index, left ventricular 
end diastolic diameter, left ventricular end systolic diameter, LVEF, shortening fraction, left 
ventricular posterior wall thickness, tricuspid valvular regurgitation presence and pericardial 
effusion. Echocardiogram should be performed using a 2-D imaging collection method.  
7.2.7. Assessment of Suicidal Ideation and Behavior –Columbia Suicide Severity Rating 
Scale (C-SSRS)
C-SSRS: The C-SSRS will be evaluated at times specified in the Schedule of Activities.  The 
Children’s Baseline/Screening (Version 6/23/10) (Appendix 1) of the C-SSRS should be 
completed at the Screening Visit (Visit 1).  At all study visits following the Screening Visit, 
the Children’s Since Last Visit (Version 6/23/10) (Appendix 2) of the C-SSRS should be 
utilized.  The Since Last Visit version refers to the subject’s experience since their last visit.
Given the sensitive nature of the subject matter of this assessment, the C-SSRS will be 
conducted with the subject’s care giver/legal guardian on the subject’s behalf throughout the 
study, rather than administering this evaluation directly with the study subjects. 
At Screening or Baseline, if the subject endorses a 4 or 5 on the C-SSRS ideation section or 
reports any suicidality behavior, then the subject is not eligible for study participation and an 
evaluation of suicide risk (risk assessment) must be completed. 
At every visit after Screening, if the subject endorses a 4 or 5 on the C-SSRS ideation section 
or reports any suicidality behavior, then the subject must be discontinued as outlined in 
Section 6, Subject Withdrawal and evaluation of suicide risk (risk assessment) must be 
completed. 
Risk Assessment: In the event that a subject endorses a 4 or 5 on the C-SSRS ideation 
section or reports any suicidality behavior, an evaluation of suicide risk (risk assessment) will 
be completed as part of the psychiatric evaluation and assessment of subject safety to 
participate will be performed by the following child and adolescent mental health provide: In 
the United States: 1) Child and Adolescent Pyschiatrists (board certified or board eligible), 
2) psychiatrist who have training and experience in the diagnosis and treatment of psychiatric 
disorders in the pediatric population, or 2) Psy. D. or Ph.D. level Clinical Psychologists, 
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licensed Master’s level Clinical Social Workers (MSW) or licensed psychiatric Nurse 
Practitioners (PNP) who have training and experience in the diagnosis and treatment of 
psychiatric disorders in the pediatric population.
Written documentation of the risk assessment should be included in the subject’s source 
documentation and the risk assessment CRF will be completed.  The risk assessment CRF 
serves as further verification that the psychiatric evaluation and assessment of subject safety 
have been completed for all subjects endorsing items 4 or 5 on the C-SSRS ideation section 
or reporting suicidal behavior. 
7.3. Banked Biospecimens
7.3.1. Markers of Drug Response
Studying the variation in genetic markers and other biomarkers may help to explain some of 
the variability in response seen with some drugs among different individuals.  This is referred 
to as pharmacogenomic/biomarker research.  Comparing the deoxyribonucleic acid (DNA), 
ribonucleic acid (RNA), protein, and metabolite variation patterns of subjects who respond 
well and those who respond poorly to treatment may help to better define the most 
appropriate group of patients in which to target a given treatment. Collecting biospecimens 
for exploratory pharmacogenomic/biomarker analyses and retaining them in the Pfizer 
BioBank makes it possible to better understand the drug’s mechanism of action and to seek 
explanations for differences in, for example, exposure, efficacy, tolerability, or safety not 
anticipated prior to the beginning of the study. Providing these biospecimens is a required 
study activity for study sites and subjects, unless prohibited as such by local regulations or 
ethics committee decision.
To protect subjects’ confidentiality, the banked biospecimens and data generated from them 
will be coded with the SSID number. Samples will be kept in a facility accessible only by 
swiping a badge. Data will be stored on password-protected computer systems. The key 
between the code and the subject’s personal identifiers will be held at the study site; the 
researchers using the biospecimens and data generated from them will not have access to the 
key nor any personally identifying information. Biospecimens will be used only for the 
purposes described here and in the informed consent document/subject information sheet; 
any other uses require additional ethical approval. Unless a time limitation is required by 
local regulations or ethical requirements, biospecimens will be stored indefinitely to allow 
for future research on the topics described here, including research conducted during the 
lengthy drug development process and also postmarketing research. Subjects can withdraw 
their consent for the use of their biospecimens at any time by making a request to the 
investigator, in which event any remaining biospecimen will be destroyed; data already 
generated from the biospecimens will continue to be stored to protect the integrity of existing
analyses. It is very unlikely that results generated from the biospecimens will have any 
clinical, diagnostic, or therapeutic implications for the individual study participants. Subjects 
are notified in the informed consent document/subject information sheet that their results will 
not be given to them, unless required by local laws or regulations, in which case results will 
be returned via the investigator. Results will not be provided to family members or other 
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physicians, nor will they be recorded in the subject’s medical record. There is no intention to 
contact subjects after completion of the clinical study.
A 2-mL blood biospecimen(Biomarker Group 1) Prep D1.5 (K2 edetic acid 
(ethylenediaminetetraacetic acid) (EDTA) whole blood collection optimized for DNA 
analysis) will be collected at the Screening visit to be retained for potential 
pharmacogenomic/biomarker analyses related to drug response, unless prohibited by local 
regulations or ethics committee decision.  For example, putative safety biomarkers, 
drug-metabolizing enzyme genes, drug-transport protein genes, or genes thought to be related 
to the mechanism of drug action may be examined.
Additional biospecimens in biomarker Group 2 will be collected in the morning following an 
8 hour fast to be retained for exploratory analyses in this study include the following:  
Biomarker Sample Group 2:

Prep B1.5 (K2 EDTA plasma collection optimized for 
biomarker/proteomic/metabonomic analysis): A 2-mL blood biospecimen will be 
collected at Visits 1(Screening), 2 (Baseline), 9, 15, 21, 25, 29, 33 or at Early 
Withdrawal, if applicable. 

Prep B2.5 (serum collection optimized for biomarker/ proteomics/metabonomic
analysis): A 2-mL blood biospecimen will be collected at Visits, 1 (Screening), 
2 (Baseline), 9, 15, 21, 25, 29, 33 or at Early Withdrawal, if applicable.
Biomarker Sample Group 3:

Prep R1 (PAXGene whole blood collection optimized for RNA analysis): A 
2.5-mL blood biospecimen will be collected at Visits 1 (Screening), 21 and 33 and 
Early Withdrawal, if applicable.

Prep P4 (Cell-free RNA): A 5-mL blood biospecimen will be collected at Visits 1 
(Screening), 21, 33, or at Early Withdrawal, if applicable.
The banked biospecimens will be collected from all subjects unless prohibited by local 
regulations or ethics committee decision.  Detailed collection, processing, storage, and 
shipment instructions are provided in the central laboratory manual.
It is possible that the use of these biospecimens may result in commercially viable products.  
Subjects will be advised in the informed consent document/subject information sheet that 
they will not be compensated in this event.
7.3.2. Additional Research
Unless prohibited by local regulations or ethics committee decision, subjects will be asked to 
indicate on the consent form whether they will allow the banked biospecimens to also be 
used for the following research:
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
Investigations of the disease under study in the clinical study, and related conditions.

Biospecimens may be used as controls.  This includes use in case-control studies of 
diseases for which Pfizer is researching drug therapies; use in characterizing the 
natural variation among people in genes, RNA, proteins, and metabolites; and use in 
developing new technologies related to pharmacogenomics/biomarkers. 
Subjects need not provide additional biospecimens for the uses described in this section; the 
biospecimen specified in the Markers of Drug Response section (7.3.1) will be used.  
Subjects may still participate in the clinical study if they elect not to allow their banked 
biospecimens to be used for the additional purposes described in this section.
7.4. Pharmacokinetics (Serum for Analysis of PF-06252616)
During all study periods, blood samples (2 mL) to provide serum for pharmacokinetic 
analysis will be collected into the appropriately labeled tubes (containing no anticoagulant or 
gel separator) at times specified in the Schedule of Activities section of the protocol. 
All efforts will be made to obtain the pharmacokinetic samples at the exact nominal time 
relative to dosing as described in the Schedule of Activities. 
Detailed collection, processing, storage, and shipment instructions are provided in the central 
laboratory manual.
Samples will be analyzed using validated analytical methods in compliance with Pfizer 
standard operating procedures.
7.5. Anti-Drug Antibody (ADA) anti-PF-06252616 and Neutralizing Antibody (NAb)
During all study periods, blood samples (2 mL) to provide serum for analysis of 
anti-PF-06252616 will be collected into the appropriately labeled tubes (containing no 
anticoagulant or gel separator) at times specified in the Schedule of Activities section of the 
protocol. 
All efforts will be made to obtain the samples at the exact nominal time relative as described 
in the Schedule of Activities.
Detailed collection, processing, storage, and shipment instructions are provided in the central 
laboratory manual.
Samples will be analyzed using validated analytical methods in compliance with Pfizer 
standard operating procedures.  All samples that are positive in a screening assay will be 
confirmed for antibody specificity and further characterized for titer.  Samples that are 
determined to be positive for ADA may be further tested for the presence of NAb.
The PK and immunogenicity samples must be processed and shipped as indicated to maintain 
sample integrity.  Any deviations from the PK sample processing steps, including any actions 
taken, must be documented and reported to the sponsor.  On a case-by-case basis, the sponsor 
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may make a determination as to whether sample integrity has been compromised.  Any 
sample deemed outside of established stability, or of questionable integrity, will be 
considered a protocol deviation.
As part of understanding the pharmacokinetics or immunogenicity of the study drug, samples 
may be used for further characterization and/or evaluation of the bioanalytical method.  
These data will be used for internal exploratory purposes and will not be included in the 
clinical report.  Samples collected for this purpose will be retained in accordance to local 
regulations and if not used within this timeframe, will be destroyed.
7.6. Pharmacodynamics/Serum for Total GDF-8
All efforts will be made to obtain the samples at the exact nominal time relative as described 
in the Schedule of Activities. 
Samples will be analyzed using a validated analytical method in compliance with Pfizer 
standard operating procedures.
The PD samples must be processed and shipped as indicated to maintain sample integrity.  
Any deviations from the PD sample processing steps, including any actions taken, must be 
documented and reported to the sponsor. On a case-by-case basis, the sponsor may make a 
determination as to whether sample integrity has been compromised.  Any sample deemed 
outside of established stability, or of questionable integrity, will be considered a protocol 
deviation.
As part of understanding the pharmacodynamics of the study drug, samples may be used for 
evaluation of the bioanalytical method.  These data will be used for internal (ie, Pfizer) 
exploratory purposes and will not be included in the clinical report.
Blood samples (2 mL) to provide serum will be collected into appropriately labeled tubes 
(silica coated, no additives).  Blood samples will be collected for the analysis of total 
GDF-8 at times specified in the Schedule of Activities.
Detailed collection, processing, storage, and shipment instructions are provided in the central 
laboratory manual.
7.7. Imaging Assessments
7.7.1. Liver MRI
Liver MRI will be obtained according to the Schedule of Activities to monitor for safety by 
quantifying iron accumulation.  The standard procedure to obtain serial liver MRIs will be 
described in an Image Acquisition manual which will be provided to the site.  The site will be 
trained on all aspects of obtaining quality liver MRIs.  MRIs will be sent to an independent 
central radiology imaging facility for calculation of the average R2* value which will be used 
to monitor for iron accumulation in the liver.  The independent central radiologist will be 
blinded to the study treatment assignment.  In order to maintain the study blind, the 
investigator and the sponsor will be blinded to the liver MRI findings, except for those from 
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screening so that the investigator may confirm eligibility.  Select sponsor study team 
members may have access to the liver MRI results however they will not have access to the 
associated subject numbers.  The Designated Reviewer will be unblinded to MRI results and 
will review results per the dose adjustment criteria described in Section 3. The R2* value 
should not be calculated by the study site as this may unblind site personnel to the treatment 
assignment. If the site reviews MRI scans for general safety, the site radiologist should 
review individual images and not reconstructed R2* maps.  Site imaging or radiology staff 
should not report suspicion of iron overload or R2* values to the investigator.  
At the initiation of the study, the post-screening liver MRI and liver iron indices results 
(serum iron, serum ferritin, total iron-binding capacity and % transferrin saturation) will not 
be provided to the site or blinded study team members as these data may be unblinding to the 
assigned treatment.  Should the E-DMC agree during their continuous review of the 
unblinded data that these data are not unblinding, the results may be provided to sites and the 
study team during the remainder of the study. 
MRIs must meet the accepted standards of quality as described in the Image Acquisition 
manual and/or Imaging Charter or the site may be asked to repeat the liver MRI. 
7.7.2. Thigh MRI
Single thigh MRI will be obtained according to the Schedule of Activities to measure the 
percent change in muscle volume.  Additional measurements may include evaluation of 
muscle quality through T2-mapping and/or Dixon imaging sequences to evaluate fat fraction.  
The standard procedure to obtain serial MRIs will be described in an Image Acquisition 
manual which will be provided to the site.  Ideally, thigh MRIs will be taken at 
approximately the same time of day (morning) to provide optimal testing conditions and 
consistency in endpoint measurements.  MRIs should not be acquired after exercise or 
strenuous activity as this could impact the study results.
The site will be trained on all aspects of obtaining quality MRIs.  MRIs will be sent to an 
independent central radiology imaging facility for analysis of the study endpoints.  The 
independent central radiologist will be blinded to the study treatment assignment. 
MRIs must meet the accepted standards of quality as described in the Image Acquisition 
manual and/or Imaging charter or the site may be asked to repeat the thigh MRI.
7.7.3. Duel-energy X-ray Absorptiometry (DXA) and X-ray
7.7.3.1. DXA
DXA scans will be obtained according to the Schedule of Activities to measure the percent 
change in lean body mass (LBM) over time and to evaluate bone mineral density (BMD) on 
the spine and whole body without head.  The standard procedure to obtain serial DXA whole 
body and spine analysis scans will be described in an Image Acquisition manual which will 
be provided to the site.  The site will be trained on all aspects of obtaining a quality whole 
body and spine scans.  Scans will be sent to an independent central radiology imaging facility 
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for analysis of the study endpoints.  The independent central reviewer will be blinded to the 
study treatment assignment. 
Screening DXA should meet the accepted standards of quality as described in the Image 
Acquisition manual and/or Imaging Charter or the site may be asked to repeat it.  Ideally, 
whole body scans will be taken at approximately the same time of day (morning) and 
subjects should avoid large meals for at least 2 hours prior to the scan. Juice, water and a 
small snack may be permitted.  Subjects should be in a state of euhydration.  Food may affect 
the lean body mass measure.  Calcium should be avoided for 24 hours as it may not absorb 
and will affect the measure of bone mineral density and lean body mass. 
7.7.3.2. X-ray
X-rays of the hand and wrist for bone age assessment will be obtained according to the 
Schedule of Activities.  The standard procedure to obtain serial hand/wrist X-rays will be 
described in an Image Acquisition manual which will be provided to the site.  The site will be 
trained on all aspects of obtaining a hand/wrist X-ray.  X-rays will be sent to an independent 
central radiology imaging facility for analysis bone age.  The independent central radiologist 
will be blinded to the study treatment assignment and the subject’s chronological age. The 
ratio of the bone age to the chronologic will be provided to the sites by the sponsor.
For subjects who may reach sexual maturity during the trial, as indicated by a Tanner 
Stage V rating, the Tanner Stage, testicular volume, hormone and X-ray (hand and wrist) will 
no longer be required to be collected to assess for signs of precocious puberty. 
7.7.3.3. Radiation Exposure
The average effective dose of radiation received for a single DXA scan or hand x-ray for 
bone age may vary due to the instrument and the subject’s body.  The expected total radiation 
dose for 7 whole body DXA exams, 3 spine scans and 7 hand x-rays for bone age assessment 
is not expected to exceed 0.75 mSv.  This is less than 1 year of natural background radiation 
which is approximately 3.0 mSv per year (EHS Radiation Risk; Blake et al, 2006).10,1
7.7.4. Additional Research with Imaging Assessments
Unless prohibited by local regulations or ethics committee decision, subjects will be asked to 
indicate on the consent form whether they will allow the images collected in this study to 
also be used to further study the disease/condition or to gain further understanding of the 
imaging methods. 
Subjects may still participate in the clinical study if they elect not to allow their images to be 
used for the additional purposes described in this section.
7.8. Functional Assessments
Functional assessments will be obtained according to the Schedule of Activities.  In order to 
provide optimal testing conditions and consistency in endpoint measurements, the functional 
assessments should be completed at approximately the same time of day and in the morning
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when the subject is rested and well-fed.  The order for completing all testing will be detailed 
in a functional assessment manual.
Should subjects become non-ambulatory during the study, the 4SC, NSAA and 6MWT will 
not continue to be collected.  
All functional assessments will be conducted by a trained physiotherapist (or exercise 
physiologist).  Throughout the study they will be referred to as “Clinical Evaluators (CEs)”.  
Training and reliability confirmation to conduct functional assessments specific to this 
protocol will be provided by a vendor (master physiotherapist [MP]).  Following the 
completion of training and reliability testing a certificate will be provided which must be in 
place prior to conducting any functional assessments.  
In order to assure ongoing quality of the CE abilities to perform functional assessments, 
videotaping will be used at pre-specified visits.  Videos will be reviewed by the MPs to 
provide feedback to the CEs on the conduct of the method used to perform the functional 
assessment. Videos will not be used to provide scoring on subject’s functional assessment.  
The videos will be stored at the site and retained per the record retention requirements 
described in Section Record Retention.
The training requirements and ongoing quality control will be provided in the Functional 
Assessment manual.
7.8.1. Forced Vital Capacity (FVC)
Pulmonary function testing will be completed to evaluate the maximal lung function utilizing 
the FVC maneuver by spirometry.
7.8.2. 4 Stair Climb (4 SC)
The primary efficacy endpoint will be based on the 4 SC (with or without the use of hand 
rails).  The 4 SC quantifies in seconds the time required for a subject to ascend 4 standard 
steps.  The method the subject uses (eg, using the hand rails) to climb the stairs is recorded to 
understand any change in technique that occurs over time, however at no time is the subject 
instructed on the preferred method (with or without the use of hand rails) used to perform this 
test.
Subjects will also be assessed on the time to descend 4 stairs.  The methods used to descend 
4 stairs will also be recorded.
7.8.3. Northstar Ambulatory Assessment (NSAA)
The NSAA is a 17-item test that grades performance of various functional skills from 
0 (unable to perform), 1 (completes independently but with modifications), and 2 (complete 
without compensation) (Mazzone et al. 2009).15 The NSAA also includes 2 timed functional 
tests: rise from floor and run 10 meters, The NSAA has been found to correlate with the 
6MWT and other functional outcomes in boys with DMD. (Mazzone et al, 2010).16
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7.8.4. Range of Motion (ROM)
Range of motion of the ankle will be evaluated by using goniometry to record any 
occurrences of ankle contractures.
7.8.5. Strength Assessment
Muscle strength will be quantified by means of a handheld dynamometer.  The following 
muscle groups will be evaluated: knee extension, elbow flexion, elbow extension and 
shoulder abduction.
7.8.6. Performance of Upper Limb (PUL)
The PUL scale has been devised to assess motor performance of the upper limb for 
individuals with dystrophinopathies (Becker and Duchenne muscular dystrophy).  The 
purpose of an upper limb scale for use in dsytrophinopathy is to assess change that occurs in 
motor performance of the upper limb overtime from when a boy is still ambulant to the time 
he loses all arm function when non-ambulant.  Motor performance will be impacted by 
muscle strength, contactures and maturational development (puberty) and the scale aims to 
incorporate performance of shoulder, elbow, wrist and hand function. 
7.8.7. Six Minute Walk Test (6MWT)
The 6MWT, originally developed for cardiac and respiratory insufficiency, has been revised
for use in DMD subjects to account for the age and unique characteristics of this population 
(McDonald et al. 2010).19 The purpose of the test is to evaluate ambulation capacity
(distance) by endurance of walking for six minutes.  This test has been widely used in natural 
history and therapeutic studies with DMD.  A sizeable variability in the range of 6 minute 
walk distance (6MWD) change at one-year (from -23 to -59 m) as well as a large standard 
deviation (SD) around the mean change (SD 81 to 90 m) were observed in all studies 
(Mazzone et al, 2013; Goemans et al, 2013; McDonald et al, 2013).17,8,20
7.9. Triggered Requirements 
Condition/ Criteria 
Action
Moderate Iron overload/ If the liver iron content 
estimate as determined by R2* value is above the “mild 
overload” threshold (R2* >190 Hz at 1.5 T or R2* 
>369 Hz at 3.0 T
The subject should be referred to a haematologist 
for further assessment
Cardiomyopathy/ If the LVEF falls below 50% on the 
cardiac MRI or echocardiogram at any follow-up visit
The subject should be referred to a cardiologist for 
further assessment.
Spine compression or fracture/ If either the bone 
mineral density increases >4% from the start of Period, 
or if there is a suspicion of a vertebral fracture upon 
central review of the DXA exam
The subject should have a local spine x-ray 
performed to confirm the presence or absences of 
compression or fracture
7.10. Infusion Site Monitoring
From the initiation of the IV infusion subjects will be monitored for signs of any infusion site 
reactions including but not limited to erythema, swelling, bruising, pain or prutitis.
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7.11. Pediatric Outcomes Data Collection Instrument (PODCI)
In order to evaluate subject’s functional health status, the PODCI questionnaire will be 
collected.  The PODCI is a patient-reported assessment of musculoskeletal health intended 
for use in children and adolescents.  The pediatric version intended for completion by parents 
or caregivers of children aged 10 years or younger will be utilized in this study.  The 
instrument is organized into multiple domains: upper extremity function, transfers and 
mobility, physical function and sports, comfort (pain free), happiness and satisfaction, and 
expectations for treatment. Each domain produces an independent score, and a summary 
total score is also computed. Scores may be reported as standardized, or they may be 
converted to normative scores based on the scores reported in a large, healthy population.
The PODCI will be collected electronically on a tablet device.
8. ADVERSE EVENT REPORTING
8.1. Adverse Events
All observed or volunteered AEs regardless of treatment group or suspected causal 
relationship to the investigational product(s) will be reported as described in the following 
sections. 
For all AEs, the investigator must pursue and obtain information adequate both to determine 
the outcome of the AE and to assess whether it meets the criteria for classification as a 
serious adverse event (SAE) requiring immediate notification to Pfizer or its designated 
representative.  For all AEs, sufficient information should be obtained by the investigator to 
determine the causality of the AE.  The investigator is required to assess causality.  
Follow-up by the investigator may be required until the event or its sequelae resolve or 
stabilize at a level acceptable to the investigator, and Pfizer concurs with that assessment.
As part of ongoing safety reviews conducted by the sponsor, any nonserious AE that is 
determined by the sponsor to be serious will be reported by the sponsor as an SAE.  To assist 
in the determination of case seriousness, further information may be requested from the 
investigator to provide clarity and understanding of the event in the context of the clinical 
study. 
8.2. Reporting Period
For SAEs, the active reporting period to Pfizer or its designated representative begins from 
the time that the subject provides informed consent, which is obtained prior to the subject’s 
participation in the study, ie, prior to undergoing any study-related procedure and/or 
receiving investigational product, through and including 84 calendar days after the last 
administration of the investigational product.  SAEs occurring to a subject after the active 
reporting period has ended should be reported to the sponsor if the investigator becomes 
aware of them; at a minimum, all SAEs that the investigator believes have at least a 
reasonable possibility of being related to investigational product are to be reported to the 
sponsor.
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
AEs (serious and nonserious) should be recorded on the case report form (CRF) from 
the time the subject has taken at least 1 dose of investigational product through the 
subject’s last visit.
8.3. Definition of an Adverse Event
An AE is any untoward medical occurrence in a clinical investigation subject administered a 
product or medical device; the event need not necessarily have a causal relationship with the 
treatment or usage.  Examples of AEs include but are not limited to: 

Abnormal test findings;

Clinically significant symptoms and signs;

Changes in physical examination findings;

Hypersensitivity;

Progression/worsening of underlying disease 

Drug abuse;

Drug dependency.
Additionally, they may include the signs or symptoms resulting from:

Drug overdose;

Drug withdrawal;

Drug misuse; 

Drug interactions;

Extravasation;

Exposure during pregnancy (EDP);

Exposure via breastfeeding;

Medication error;

Occupational exposure.
8.4. Medication Errors
Medication errors may result, in this study, from the administration or consumption of the 
wrong product, by the wrong subject, at the wrong time, or at the wrong dosage strength.  
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Such medication errors occurring to a study participant are to be captured on the medication 
error CRF which is a specific version of the AE page, and on the SAE form when 
appropriate.  In the event of medication dosing error, the sponsor should be notified 
immediately.
Medication errors are reportable irrespective of the presence of an associated AE/SAE, 
including:

Medication errors involving subject exposure to the investigational product;

Potential medication errors or uses outside of what is foreseen in the protocol that do 
or do not involve the participating subject.
Whether or not the medication error is accompanied by an AE, as determined by the
investigator, the medication error is captured on the medication error version of the AE page 
and, if applicable, any associated AE(s) are captured on an AE CRF page. 
8.5. Abnormal Test Findings
The criteria for determining whether an abnormal objective test finding should be reported as 
an AE are as follows: 

Test result is associated with accompanying symptoms; and/or

Test result requires additional diagnostic testing or medical/surgical intervention;
and/or

Test result leads to a change in study dosing (outside of protocol-stipulated dose 
adjustments) or discontinuation from the study, significant additional concomitant 
drug treatment, or other therapy; and/or

Test result is considered to be an AE by the investigator or sponsor.
Merely repeating an abnormal test, in the absence of any of the above conditions, does not 
constitute an AE.  Any abnormal test result that is determined to be an error does not require 
reporting as an AE.
8.6. Serious Adverse Events
A serious advese event (SAE) is any untoward medical occurrence at any dose that:

Results in death;

Is life-threatening (immediate risk of death);

Requires inpatient hospitalization or prolongation of existing hospitalization;
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
Results in persistent or significant disability/incapacity (substantial disruption of the 
ability to conduct normal life functions);

Results in congenital anomaly/birth defect.
Medical and scientific judgment is exercised in determining whether an event is an important 
medical event.  An important medical event may not be immediately life-threatening and/or 
result in death or hospitalization.  However, if it is determined that the event may jeopardize 
the subject or may require intervention to prevent one of the other AE outcomes, the 
important medical event should be reported as serious.
Examples of such events are intensive treatment in an emergency room or at home for 
allergic bronchospasm; blood dyscrasias or convulsions that do not result in hospitalization; 
or development of drug dependency or drug abuse.
8.6.1. Protocol-Specified Serious Adverse Events 
Unless the investigator believes that there is a causal relationship between the investigational 
product and an event specified below, these events should not be reported by the investigator 
as SAEs as described in the Serious Adverse Event Reporting Requirements section of this 
protocol. These events are anticipated to occur commonly in a population with DMD.  
However, these events should still be captured as AEs in the CRF.
Protocol-specified events that will not normally be reported in an expedited manner: 
1. Loss of mobility or ambulation.
2. Muscle weakness.
3. Symptoms related to spinal deformity.
4. Respiratory muscle weakness/Hypoxia.
5. Fracture.
6. Steroid related metabolic changes (Hypertension, diabetes).
Should an aggregate analysis indicate that these pre-specified events occur more frequently 
than expected based on the expectation of frequency of the event(s) in question in the 
population for comparison, eg, based on epidemiologial data, literature, or other data, then 
this will be submitted and reported in accordance with Pfizer’s safety reporting requirements.  
Aggregate analysis of safety data will be performed on a regular basis per internal standard 
operating procedures and on a quarterly basis by the DMC. 
8.6.2. Potential Cases of Drug-Induced Liver Injury 
Abnormal values in aspartate aminotransferase (AST) and/or alanine aminotransferase (ALT) 
levels concurrent with abnormal elevations in total bilirubin level that meet the criteria 
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outlined below in the absence of other causes of liver injury are considered potential cases of 
drug-induced liver injury (potential Hy’s law cases) and should always be considered 
important medical events.  
The threshold of laboratory abnormalities for a potential case of drug-induced liver injury 
depends on the subject’s individual baseline values and underlying conditions. Subjects who 
present with the following laboratory abnormalities should be evaluated further to 
definitively determine the etiology of the abnormal laboratory values:

Subjects with AST or ALT and total bilirubin baseline values within the normal range 
who subsequently present with AST or ALT values 3 times the upper limit of 
normal (x ULN) concurrent with a total bilirubin value 2 x ULN with no evidence of 
hemolysis and an alkaline phosphatase value 2 x ULN or not available;

For subjects with preexisting ALT OR AST OR total bilirubin values above the 
ULN, the following threshold values should be used in the definition mentioned 
above:

For subjects with preexisting AST or ALT baseline values above the normal 
range: AST or ALT values 2 times the baseline values and 3 x ULN, or 
8 x ULN (whichever is smaller).
Concurrent with

For subjects with preexisting values of total bilirubin above the normal range: 
Total bilirubin level increased from baseline by an amount of at least 1 x ULN or
if the value reaches 3 x ULN (whichever is smaller).
The subject should return to the investigational site and be evaluated as soon as possible, 
preferably within 48 hours from awareness of the abnormal results.  This evaluation should 
include laboratory tests, detailed history, and physical assessment. 
In addition to repeating measurements of AST and ALT, laboratory tests should include 
albumin, creatine kinase, total bilirubin, direct and indirect bilirubin, GGT, GLDH, PT/INR, 
and alkaline phosphatase.  A detailed history, including relevant information, such as review 
of ethanol, acetaminophen, recreational drug and supplement consumption, family history, 
occupational exposure, sexual history, travel history, history of contact with a jaundiced 
person, surgery, blood transfusion, history of liver or allergic disease, and work exposure, 
should be collected.  Further testing for acute hepatitis A, B, or C infection and liver imaging 
(eg, biliary tract) may be warranted. All cases confirmed on repeat testing as meeting the 
laboratory criteria defined above, with no other cause for liver function test (LFT)
abnormalities identified at the time, should be considered potential Hy’s law cases 
irrespective of availability of all the results of the investigations performed to determine 
etiology of the abnormal LFTs.  Such potential Hy’s law cases should be reported as SAEs.
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8.7. Hospitalization
Hospitalization is defined as any initial admission (even less than 24 hours) in a hospital or 
equivalent healthcare facility or any prolongation of an existing admission.  Admission also 
includes transfer within the hospital to an acute/intensive care unit (eg, from the psychiatric 
wing to a medical floor, medical floor to a coronary care unit, or neurological floor to a 
tuberculosis unit).  An emergency room visit does not necessarily constitute a hospitalization; 
however, the event leading to the emergency room visit should be assessed for medical 
importance.
Hospitalization does not include the following:

Rehabilitation facilities;

Hospice facilities;

Respite care (eg, caregiver relief);

Skilled nursing facilities;

Nursing homes;

Same-day surgeries (as outpatient/same-day/ambulatory procedures).
Hospitalization or prolongation of hospitalization in the absence of a precipitating, clinical 
AE is not in itself an SAE.  Examples include: 

Admission for treatment of a preexisting condition not associated with the 
development of a new AE or with a worsening of the preexisting condition (eg, for 
workup of persistent pre-treatment laboratory abnormality);

Social admission (eg, subject has no place to sleep);

Administrative admission (eg, for yearly physical examination);

Protocol-specified admission during a study (eg, for a procedure required by the study 
protocol);

Optional admission not associated with a precipitating clinical AE (eg, for elective 
cosmetic surgery);

Hospitalization for observation without a medical AE;

Preplanned treatments or surgical procedures.  These should be noted in the baseline 
documentation for the entire protocol and/or for the individual subject;
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Diagnostic and therapeutic noninvasive and invasive procedures, such as surgery, should not 
be reported as AEs.  However, the medical condition for which the procedure was performed 
should be reported if it meets the definition of an AE.  For example, an acute appendicitis 
that begins during the AE reporting period should be reported as the AE and the resulting 
appendectomy should be recorded as treatment of the AE.
8.8. Severity Assessment
If required on the AE CRFs, the investigator will use the adjectives MILD, MODERATE, or 
SEVERE to describe the maximum intensity of the AE.  For purposes of consistency, these 
intensity grades are defined as follows:
MILD
Does not interfere with subject's usual function.
MODERATE
Interferes to some extent with subject's usual function.
SEVERE
Interferes significantly with subject's usual function.
Note the distinction between the severity and the seriousness of an AE.  A severe event is not 
necessarily an SAE.  For example, a headache may be severe (interferes significantly with 
the subject's usual function) but would not be classified as serious unless it met one of the 
criteria for SAEs, listed above.
8.9. Causality Assessment
The investigator’s assessment of causality must be provided for all AEs (serious and 
nonserious); the investigator must record the causal relationship in the CRF, as appropriate, 
and report such an assessment in accordance with the SAE reporting requirements if 
applicable.  An investigator’s causality assessment is the determination of whether there 
exists a reasonable possibility that the investigational product caused or contributed to an 
AE; generally the facts (evidence) or arguments to suggest a causal relationship should be 
provided.  If the investigator does not know whether or not the investigational product caused 
the event, then the event will be handled as “related to investigational product” for reporting 
purposes, as defined by the sponsor (see the section on Reporting Requirements).  If the 
investigator's causality assessment is "unknown but not related to investigational product," 
this should be clearly documented on study records. 
In addition, if the investigator determines that an SAE is associated with study procedures, 
the investigator must record this causal relationship in the source documents and CRF, as 
appropriate, and report such an assessment in accordance with the SAE reporting 
requirements, if applicable.
8.10. Exposure During Pregnancy
For both approved/unlicensed products and for marketed products, an exposure during 
pregnancy occurs if:
1. A female becomes, or is found to be, pregnant either while receiving or having been 
exposed (eg, because of treatment or environmental exposure) to the investigational 
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product; or the female becomes, or is found to be pregnant after discontinuing and/or 
being exposed to the investigational product;
An example of environmental exposure would be a case involving direct contact with 
a Pfizer product in a pregnant woman (eg, a nurse reports that she is pregnant and has 
been exposed to chemotherapeutic products).
2. A male has been exposed (eg, because of treatment or environmental exposure) to the 
investigational product prior to or around the time of conception and/or is exposed 
during his partner’s pregnancy.
If a study subject or study subject’s partner becomes or is found to be pregnant during the 
study subject’s treatment with the investigational product, the investigator must submit this 
information to the Pfizer drug safety unit on a SAE report form and an EDP supplemental 
form, regardless of whether an SAE has occurred.  In addition, the investigator must submit 
information regarding environmental exposure to a Pfizer product in a pregnant woman (eg, a 
subject reports that she is pregnant and has been exposed to a cytotoxic product by inhalation 
or spillage) using the EDP supplemental form.  This must be done irrespective of whether an 
AE has occurred and within 24 hours of awareness of the exposure. The information 
submitted should include the anticipated date of delivery (see below for information related 
to termination of pregnancy).
Follow-up is conducted to obtain general information on the pregnancy and its outcome for 
all EDP reports with an unknown outcome.  The investigator will follow the pregnancy until 
completion (or until pregnancy termination) and notify Pfizer of the outcome as a follow-up 
to the initial EDP supplemental form.  In the case of a live birth, the structural integrity of the
neonate can be assessed at the time of birth.  In the event of a termination, the reason(s) for 
termination should be specified and, if clinically possible, the structural integrity of the 
terminated fetus should be assessed by gross visual inspection (unless pre-procedure test 
findings are conclusive for a congenital anomaly and the findings are reported).
If the outcome of the pregnancy meets the criteria for an SAE (ie, ectopic pregnancy, 
spontaneous abortion, intrauterine fetal demise, neonatal death, or congenital anomaly [in a 
live born baby, a terminated fetus, an intrauterine fetal demise, or a neonatal death]), the 
investigator should follow the procedures for reporting SAEs.
Additional information about pregnancy outcomes that are reported as SAEs follows: 

Spontaneous abortion includes miscarriage and missed abortion;

Neonatal deaths that occur within 1 month of birth should be reported, without regard 
to causality, as SAEs.  In addition, infant deaths after 1 month should be reported as 
SAEs when the investigator assesses the infant death as related or possibly related to 
exposure to the investigational product.
Additional information regarding the EDP may be requested by the investigator.  Further 
follow-up of birth outcomes will be handled on a case-by-case basis (eg, follow-up on 
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preterm infants to identify developmental delays). In the case of paternal exposure, the 
investigator will provide the study subject with the Pregnant Partner Release of Information 
Form to deliver to his partner. The investigator must document in the source documents that 
the subject was given the Pregnant Partner Release of Information Form to provide to his 
partner.
8.11. Occupational Exposure
An occupational exposure occurs when during the performance of job duties, a person 
(whether a healthcare professional or otherwise) gets in unplanned direct contact with the 
product, which may or may not lead to the occurrence of an AE.
An occupational exposure is reported to the drug safety unit within 24 hours of the 
investigator’s awareness, using the SAE report form, regardless of whether there is an 
associated AE/SAE.  Since the information does not pertain to a subject enrolled in the study, 
the information is not reported on a CRF, however a copy of the completed SAE Report form 
is maintained in the investigator site file.
8.12. Withdrawal Due to Adverse Events (See Also the Section on Subject Withdrawal)
Withdrawal due to AEs should be distinguished from withdrawal due to other causes, 
according to the definition of AE noted earlier, and recorded on the appropriate AE CRF 
page. 
When a subject withdraws because of an SAE, the SAE must be reported in accordance with 
the reporting requirements defined below.
8.13. Eliciting Adverse Event Information
The investigator is to report all directly observed AEs and all AEs spontaneously reported by 
the study subject’s parent/legal guardian/ legally acceptable representative.  In addition, each 
study subject’s parent/ guardian/legally acceptable representative will be questioned about 
AEs.
8.14. Reporting Requirements
Each AE is to be assessed to determine if it meets the criteria for SAEs.  If an SAE occurs, 
expedited reporting will follow local and international regulations, as appropriate.
8.14.1. Serious Adverse Event Reporting Requirements
If an SAE occurs, Pfizer is to be notified within 24 hours of investigator awareness of the 
event.
As noted in the Protocol-Specified Serious Adverse Events section, should an investigator 
judge one of the identified protocol-specified SAEs to have a causal relationship with the 
investigational product the investigator must report the event to the sponsor within 24 hours 
of investigator awareness, even if that event is a component of the endpoint.
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In particular, if the SAE is fatal or life-threatening, notification to Pfizer must be made 
immediately, irrespective of the extent of available AE information.  This time frame also 
applies to additional new information (follow-up) on previously forwarded SAE reports as 
well as to the initial and follow-up reporting of EDP, exposure via breastfeeding, and 
occupational exposure cases. 
In the rare event that the investigator does not become aware of the occurrence of an SAE
immediately (eg, if an outpatient study subject initially seeks treatment elsewhere), the 
investigator is to report the event within 24 hours after learning of it and document the time 
of his or her first awareness of the AE.
For all SAEs, the investigator is obligated to pursue and provide information to Pfizer in 
accordance with the time frames for reporting specified above.  In addition, an investigator 
may be requested by Pfizer to obtain specific additional follow-up information in an 
expedited fashion.  This information collected for SAEs is more detailed than that captured 
on the AE CRF.  In general, this will include a description of the AE in sufficient detail to 
allow for a complete medical assessment of the case and independent determination of 
possible causality.  Information on other possible causes of the event, such as concomitant 
medications, vaccines, and/or illnesses, must be provided.  In the case of a subject death, a 
summary of available autopsy findings must be submitted as soon as possible to Pfizer or its 
designated representative. 
8.14.2. Nonserious Adverse Event Reporting Requirements
All AEs will be reported on the AE page(s) of the CRF.  It should be noted that the form for 
collection of SAE information is not the same as the AE CRF.  Where the same data are 
collected, the forms must be completed in a consistent manner.  For example, the same AE
term should be used on both forms.  AEs should be reported using concise medical 
terminology on the CRFs as well as on the form for collection of SAE information.
8.14.3. Sponsor’s Reporting Requirements to Regulatory Authorities
AE reporting, including suspected unexpected serious adverse reactions will be carried out in 
accordance with applicable local regulations.
9. DATA ANALYSIS/STATISTICAL METHODS
Detailed methodology for summary and statistical analyses of the data collected in this study 
will be documented in a statistical analysis plan (SAP), which will be maintained by the 
sponsor.  This document may modify the plans outlined in the protocol; however, any major 
modifications of the primary endpoint definition and/or its analysis will also be reflected in a 
protocol amendment.
9.1. Sample Size Determination
The sample size is based on the primary endpoint of demonstrating efficacy of change from 
baseline on a 4 stair climb timed function test as compared to placebo at 49 weeks.  To detect 
a 2.5 second difference in change from baseline in 4 stair climb based on a difference 
between the active treatment and the placebo treatment in Period 1 assuming a common 
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standard deviation of 4.0 with 80% power at =0.05 (two-sided), a 2:1 treatment allocation
and one interim analysis a total of 96 subjects should complete 49 weeks of dosing for this 
assessment.  Assuming a 10% attrition rate, approximately 105 subjects should be enrolled 
(70 subjects receiving PF-06252616 and 35 subjects receiving placebo) in order to ensure 
sufficient number of subjects will complete this assessment.  If there are no safety issues and 
enrollment has completed, additional subjects may be enrolled prior to the time of the interim 
analysis. These additional subjects may help off-set any unforeseen variability that may 
occur outside the presumed standard deviation for this age group. 
One interim analysis is planned to evaluate futility and efficacy after approximately 50% of 
the subjects have completed through Week 49.  Alpha- and beta-spending functions will be 
used to determine the cutoffs for efficacy and futility at the interim based on the observed 
number of subjects in the interim analysis.  The gamma family spending functions will be 
used to appropriately account for error spending and adjust for the observed information at 
the time of the interim analysis and conservative boundaries (-1) will be used to define the 
futility and efficacy boundaries. The cutoff used at the interim analysis will be calculated 
based on the percentage of subjects included at the interim analysis to ensure appropriate 
protection of the type I error. Further details regarding the interim analysis and simulations 
are included in the SAP.
9.2. Efficacy Analysis
Continuous variables will be summarized by the N, mean, median, standard deviation, 
minimum and maximum.  Categorical variables will be summarized by percent and counts.  
All summaries will be displayed by treatment group and/or period depending on the 
endpoint.  Efficacy data will be listed, tabulated and graphically represented, as appropriate.  
Model assumptions will be tested using appropriate statistical or graphical techniques.
All analyses will be based on the full analysis set (FAS) which includes all randomized 
subjects who have received at least one dose of study drug.  Additionally analyses based on a 
per protocol analysis set may also be performed.
9.2.1. Analysis of the Primary Endpoint 
Change from baseline in 4 stair climb will be analyzed using a longitudinal mixed effects 
model.  The baseline result, treatment, time and treatment by time interaction will be 
included as fixed effects in the model.  Subject will be included as a random effect and the 
model will be fit with an unstructured covariance for the repeated measures.  The distribution 
of the time to climb 4 stairs is assumed to be right skewed.  Transformations of the time to 
climb 4 stairs (including the log transformation) will be evaluated to ensure the normality 
assumption is met.  Contrasts will be created to estimate the differences in change from 
baseline time in 4 stair climb at the end of each dose treatment levels for Period 1 (Week 17, 
Week 33 and Week 49).  The final analysis of the primary endpoint will be performed at 
Week 49, though data will continue to be collected through Week 97.  Additionally, 
non-Gaussian models may be explored in the case of non-normal data for the time to climb 
4 stairs.
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Missing data will be handled using maximum likelihood techniques for a mixed effects 
model.  This analysis is unbiased under the assumption of missing at random when the model 
assumptions hold.  Subjects who lose the ability to climb 4 stairs and/or ambulate will be 
missing not at random.  Additional imputation methods to assess the sensitivity of the 
analysis to missing not at random data will also be performed.  A completer analysis will also 
be conducted as a sensitivity analysis.
A sensitivity analysis of the time to climb 4 stairs will be based on the velocity (defined as 
the reciprocal of time).  This analysis will use the same longitudinal model, but subjects who 
can no longer ambulate will be analyzed with a velocity of 0 instead of a missing time to 
climb 4 stairs at that time point, as specified above.  Thus the missing data will no longer be 
handled by the maximum likelihood techniques under the missing at random assumption for 
subjects who can longer complete the 4 stair climb.  Based on the number of subjects who 
cannot complete the function test at Week 49, a zero inflation model may also be explored 
for the velocity endpoint.
Additionally, a non-parametric sensitivity analysis may be performed on the Week 49 data if 
there is a large number of subjects who can no longer ambulate.  The proportion of subjects 
who can no longer complete the test will also be compared between the two treatment groups 
at the Week 49 time point along with a time to failure analysis comparing the two treatment 
groups based on the ability to complete the test.
9.2.2. Analysis of the Secondary Endpoints
Secondary endpoints of change from baseline in FVC, NSAA, ROM, PUL, 6MWD, 
myometry based strength assessments, and MRI volume endpoints will be analyzed using the 
same longitudinal mixed model as described for the primary analysis.  Transformation of the 
data will also be considered if model assumptions are not met.
Additionally, a sensitivity analysis based on velocity may also be performed as described for 
the primary analysis for timed function tests.
In a pre-specified subset of subjects who may demonstrate a rapid disease decline and with 
relatively low variablity , the mean change from baseline as compared to placebo on 
functional testing (4SC, FVC, NSAA, PUL, 6MWD will be evaluated. 
9.2.2.1. Historic Control
In keeping with global guidance (eg, Food and Drug Administration’s Guidance from 2015: 
Duchenne Muscular Dystrophy and Related Dystrophinopathies: Developing Drugs for 
Treatment and Eurpoean Medicinal Agency[EMA]/Committee for Medicinal Product for 
Human Use [CHMP] Guideline on the Clinical Investigation of Medicinal Products for the 
Treatment of Duchenne and Becker muscular dystrophy, 2016) and related advice received
from regulators,  the long-term effects on functional assessments following approximately 
2-years of treatment with PF-06252616 will be characterized compared to a historical control 
group. 
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9.2.3. Analysis of the Exploratory Endpoints
All exploratory endpoints, including the pharmacologic and health outcome endpoints, will 
be summarized by treatment group and period.  Additional analyses may be performed to 
understand the relationship between these endpoints and treatment.  Analyses of the primary 
and secondary endpoints during Period 2 will be considered exploratory.  These endpoints 
will be summarized by period and additional analyses may be performed.
9.2.4. Analysis of Pharmacokinetics
The PK concentration population is defined as all enrolled subjects who received at least 
1 dose of PF-06252616 and in whom at least 1 concentration value is reported.  The PK 
parameter analysis population is defined as all enrolled subjects who received at least 1 dose 
of PF-06252616 and in whom at least 1 of the PK parameters of interest is calculated. 
PK parameters for PF-06252616 following administration of PF-06252616 will be derived 
from the concentration-time profiles as described in the following table.  For subjects in 
Sequence 2, PK samples collected during placebo treatment in Period 2 will be used to 
estimate t½ following the last dose of active treatment in Period 1. 
PK parameters for PF-06252616 following administration of PF-06252616 will be derived 
from the concentration-time profiles as described.
Parameter
Definition
Method of Determination
Cmax
Maximum serum concentration
Observed directly from data
Tmax
Time for Cmax
Observed directly from data
Ctrough
Trough (predose) serum concentration
Observed directly from data
AUC
Area under the serum concentration-time 
curve over the dosing interval τ, where =4 
week (672 hours)
Linear/Log trapezoidal method
Cav
Average serum concentration over the 
dosing interval
AUC/
t½
a
Terminal elimination half-life 
Log e(2)/kel, where kel is the terminal 
phase rate constant calculated by a 
linear regression of the log-linear 
concentration-time curve.  Only those 
data points judged to describe the 
terminal log-linear decline will be used 
in regression 
CL
Clearance
Dose/AUC
VSS
a
Volume of distribution at steady state
CL * MRT, where MRT is the mean 
residence time
a If data permit
The serum PF-06252616 concentrations and PK parameters will be summarized through 
appropriate data tabulations, descriptive statistics, and graphical presentations which will be 
detailed in the statistical analysis plan.  Briefly, serum concentrations for PF-06252616 will 
be listed and summarized descriptively by nominal PK sampling time and dose.  Individual 
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subject and median profiles of the serum concentration time data will be plotted for subjects 
with additional PK sampling.
The PK parameters will be summarized for subjects in the PK parameter analysis set.  Each 
PK parameter will include the set of summary statistics as specified in the table below:
Parameter
Summary statistics
Cmax, AUC, Cav 
Ctrough, CL, VSS
N, arithmetic mean, median, cv%, standard deviation, minimum, maximum, 
geometric mean, geometric CV%
t½
N, arithmetic mean, median, cv%, standard deviation, minimum, maximum
Tmax
N, median, minimum, maximum
Any population PK analysis if conducted will be reported separately. 
9.2.5. Analysis of Pharmacodynamics
The GDF-8 concentration population is defined as all enrolled subjects in whom at least 
1 concentration value is reported.  The GDF-8 parameter analysis population is defined as all 
enrolled subjects who received at least 1 dose of PF-0625616 and in whom at least 1 of the 
parameters of interest is calculated.
Graphical analysis of total GDF-8 levels as absolute and percentage of baseline will be 
performed.  Longitudinal analyses will be employed to determine the effects of dose and 
concentration on the GDF-8 levels over time.  From the GDF-8 data the following 
parameters will be reported. 
Parameter
Definition
Method of Determination
AUCτ(GDF-8)
Area under GDF-8 curve over the 
4-week dosing interval for 
PF-06252616
Linear trapezoidal method
Cmax(GDF-8)
Maximum concentration of GDF-8 
Observed directly from data
Tmax(GDF-8)
Time to maximum GDF-8 
concentration
Observed directly from data
CGDF-8(0)
Baseline GDF-8 (Day 1 predose)
Observed directly from data
Ctrough,(GDF-8)
Trough (predose) serum 
Observed directly from data
Cav (GDF-8)
Average GDF-8 concentration over 
dosing interval
AUCτ(GDF-8)/ 
The GDF-8 parameters will be summarized by treatment and will include the set of summary 
statistics as specified in the table below:
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Parameter
Summary statistics
AUC(GDF-8),, 
Cmax(GDF-8), 
Tmax(GDF-8),   
CGDF-8(0),
Ctrough,(GDF-8),
Cav (GDF-8)
N, arithmetic mean, median, cv%, standard deviation, minimum, maximum, 
geometric mean
Tmax
N, median, minimum, maximum
Any population PK/PD analysis conducted will be reported separately.
Additionally, data permitting relationships between PF-06252616 PK, GDF-8, imaging data 
(DXA, MRI), 4 stair climb, immunogenicity and any safety signals may be explored.
9.3. Safety Analysis
Safety analyses will be based on the full analysis set. 
9.3.1. Vital Signs
Vital signs will be listed and tabulated by dose group and week with descriptive statistics.  
Change from baseline will also be summarized using the same descriptive statistics by dose 
group and month.
9.3.2. Electrocardiogram
The following ECG data will be listed: QT, QTc (Fridericia’s), heart rate, QRS duration, PR 
and RR interval.  
Baseline and change from baseline for QT, QTcF, heart rate, QRS, PR and RR will be 
summarized using descriptive statistics by treatment and study week.  The baseline for ECG 
parameters will be the average of the triplicate pre-dose measurements at Week 0.  Any 
triplicate measurements will be averaged prior to the calculation of summary statistics.  For 
QTcF a classification of absolute values and increase from baseline will be used.
The number of subjects with average of the triplicate QTcF <450 ms, 450 ms QTcF 
<480 ms, 480 ms QTcF <500 ms and QTcF values 500 ms will be tabulated by treatment 
and study week.  The number of subjects with maximum increase from baseline QTcF 
<30 ms, 30 ms QTcF <60 ms and QTcF 60 ms will be tabulated by treatment and study 
week.  In addition, the number of subjects with uncorrected QT values 500 ms will be 
summarized.
Triplicate measures will be averaged prior to categorizing subjects.  However, the number of 
subjects with any single uncorrected QT value 500 ms (not the average) will be 
summarized.
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9.3.3. Cardiac MRI/Echocardiogram
The mean absolute and percent change from baseline in LVEF will be evaluated as compared 
to placebo.  Exploratory analyses comparing left ventricular wall thickness, ventricular wall 
strain and cardiac fibrosis against placebo will be performed where data from cardiac MRI 
are available.
9.3.4. Liver MRI
The mean absolute and percent change from baseline in the R2* value will be tabulated for 
each subject.  Other exploratory analyses may be performed to compare the treatments.
9.3.5. Other Safety
Adverse event data, laboratory data and concomitant medications will be tabulated and listed 
but not subjected to formal statistical analysis.
Other safety data will be listed.
9.4. Interim Analysis
An interim analysis will be conducted after approximately 50% of the subjects have 
completed assessments at Week 49.  The futility and efficacy boundaries will be calculated 
based on the gamma family alpha- and beta-spending and conservative stopping boundaries 
(-1) will be implemented for the futility and efficacy boundaries.  The cutoff used at the 
interim analysis will be calculated based on the percentage of subjects included at the interim 
analysis to ensure appropriate protection of the type I error.  A statistical and programming 
team independent from the study team will conduct all unblinded analyses to be forwarded to 
the external data monitoring committee (E-DMC) and will maintain the study blind per 
Pfizer’s SOPs.  Further details of the interim analysis will be included in the final SAP.  This 
analysis plan will be approved prior to the unblinding of the independent statistical and 
programming team.
9.5. Data Monitoring Committee 
This study will use an E-DMC. 
The E-DMC will be responsible for ongoing monitoring of safety and the efficacy at the 
interim analysis and safety of subjects in the study according to the charter.  The 
recommendations made by the E-DMC in regards to safety or interim efficacy to alter the 
conduct of the study will be forwarded to the sponsor management for final decision.  Pfizer 
will forward such decisions, which may include summaries of aggregate analyses of endpoint 
events and of safety data that are not endpoints, to regulatory authorities, as appropriate.  
Details of the composition of the E-DMC and sponsor management including interactions 
between them will be further specified in the DMC charter.  See Section 3.5.2 for additional 
information.
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10. QUALITY CONTROL AND QUALITY ASSURANCE
Pfizer or its agent will conduct periodic monitoring visits during the study conduct to ensure 
that the protocol and Good Clinical Practices (GCPs) are being followed.  The monitors may 
review source documents to confirm that the data recorded on CRFs are accurate.  The 
investigator and institution will allow Pfizer monitors/auditors or its agents and appropriate 
regulatory authorities direct access to source documents to perform this verification. This 
verification may also occur after study completion.
During the study conduct and/or after completion, the study site may be subject to review by 
the institutional review board (IRB)/ethics committee (EC), and/or to quality assurance audits 
performed by Pfizer, or companies working with or on behalf of Pfizer, and/or to inspection 
by appropriate regulatory authorities.
The investigator(s) will notify Pfizer or its agents immediately of any regulatory inspection 
notification in relation to the study. Furthermore, the investigator will cooperate with Pfizer 
or its agents to prepare the study site for the inspection and will allow Pfizer or its agent, 
whenever feasible, to be present during the inspection. The investigator will promptly 
provide copies of the inspection findings to Pfizer or its agent.  Before response submission 
to the regulatory authorities, the investigator will provide Pfizer or its agents with an 
opportunity to review and comment on responses to any such findings.
It is important that the investigator(s) and their relevant personnel are available during the 
monitoring visits and possible audits or inspections and that sufficient time is devoted to the 
process.
11. DATA HANDLING AND RECORD KEEPING
11.1. Case Report Forms/Electronic Data Record
As used in this protocol, the term CRF should be understood to refer to either a paper form or 
an electronic data record or both, depending on the data collection method used in this study.
A CRF is required and should be completed for each included subject.  The completed 
original CRFs are the sole property of Pfizer and should not be made available in any form to 
third parties, except for authorized representatives of Pfizer or appropriate regulatory 
authorities, without written permission from Pfizer.
The investigator has ultimate responsibility for the collection and reporting of all clinical, 
safety, and laboratory data entered on the CRFs and any other data collection forms (source 
documents) and ensuring that they are accurate, authentic/original, attributable, complete, 
consistent, legible, timely (contemporaneous), enduring, and available when required.  The 
CRFs must be signed by the investigator or by an authorized staff member to attest that the 
data contained on the CRFs are true. Any corrections to entries made in the CRFs or source 
documents must be dated, initialed, and explained (if necessary) and should not obscure the 
original entry. 
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In most cases, the source documents are the hospital's or the physician's subject chart.  In 
these cases, data collected on the CRFs must match the data in those charts. 
In some cases, the CRF, or part of the CRF, may also serve as source documents.  In these 
cases, a document should be available at the investigative site as well as at Pfizer and clearly 
identify those data that will be recorded in the CRF, and for which the CRF will stand as the 
source document.
11.2. Record Retention
To enable evaluations and/or audits from regulatory authorities or Pfizer, the investigator 
agrees to keep records, including the identity of all participating subjects (sufficient 
information to link records, eg, CRFs and hospital records), all original signed informed 
consent/assent documents, copies of all CRFs, safety reporting forms, source documents, and 
detailed records of treatment disposition, and adequate documentation of relevant 
correspondence (eg, letters, meeting minutes, and telephone call reports).  The records should 
be retained by the investigator according to ICH guidelines, according to local regulations, or 
as specified in the clinical study agreement (CSA), whichever is longer.
If the investigator becomes unable for any reason to continue to retain study records for the 
required period (eg, retirement, relocation), Pfizer should be prospectively notified.  The 
study records must be transferred to a designee acceptable to Pfizer, such as another 
investigator, another institution, or an independent third party arranged by Pfizer. 
Investigator records must be kept for a minimum of 15 years after completion or 
discontinuation of the study or for longer if required by applicable local regulations.
The investigator must obtain Pfizer's written permission before disposing of any records, 
even if retention requirements have been met.
12. ETHICS
12.1. Institutional Review Board (IRB)/Ethics Committee (EC)
It is the responsibility of the investigator to have prospective approval of the study protocol, 
protocol amendments, informed consent/assent documents, and other relevant documents, 
eg, recruitment advertisements, if applicable, from the IRB/EC.  All correspondence with the 
IRB/EC should be retained in the investigator file.  Copies of IRB/EC approvals should be 
forwarded to Pfizer.
The only circumstance in which an amendment may be initiated prior to IRB/EC approval is 
where the change is necessary to eliminate apparent immediate hazards to the subjects.  In 
that event, the investigator must notify the IRB/EC and Pfizer in writing immediately after 
the implementation.
12.2. Ethical Conduct of the Study
The study will be conducted in accordance with legal and regulatory requirements, as well as 
the general principles set forth in the International Ethical Guidelines for Biomedical 
Research Involving Human Subjects (Council for International Organizations of Medical 
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Sciences 2002), Guidelines for GCP (ICH 1996), and the Declaration of Helsinki (World 
Medical Association 1996 & 2008). 
In addition, the study will be conducted in accordance with the protocol, the ICH guideline 
on GCP, and applicable local regulatory requirements and laws.
12.3. Subject Information and Consent
All parties will ensure protection of subject personal data and will not include subject names 
or other identifiable data in any reports, publications, or other disclosures, except where
required by law.
When study data are compiled for transfer to Pfizer and other authorized parties, subject 
names, addresses, and other identifiable data will be replaced by a numerical code based on a 
numbering system provided by Pfizer in order to de-identify study subjects. The use of 
initials should be avoided.  The study site will maintain a confidential list of subjects who 
participated in the study linking each subject’s numerical code to the his or her actual 
identity.  In case of data transfer, Pfizer will maintain high standards of confidentiality and 
protection of subjects’ personal data consistent with applicable privacy laws.
The informed consent/assent documents must be in compliance with ICH GCP, local 
regulatory requirements, and legal requirements, including applicable privacy laws.
The informed consent/assent documents used during the informed consent process must be 
reviewed and approved by the sponsor, approved by the IRB/EC before use, and available for 
inspection.
The investigator must ensure that each study subject, or his legally acceptable representative, 
or parent(s) or legal guardian if a minor, is fully informed about the nature and objectives of 
the study and possible risks associated with participation. 
Whenever consent is obtained from a subject’s legeally acceptable representative/parent(s) or 
legal guardian, the subject’s assent (affirmative agreement) must subsequently be obtained 
when the subject has the capacity to provide assent, as determined by the IRB/EC.  If the 
investigator determines that a subject’s decisional capacity is so limited he/she cannot 
reasonably be consulted, then, as permitted by the IRB/EC and consistent with local 
regulatory and legal requirements, the subject’s assent may be waived with source 
documentation of the reason assent was not obtained.  If the study subject does not provide 
his or her own consent, the source documents must record why the subject did not provide 
consent (eg, minor, decisionally impaired adult), how the investigator determined that the 
person signing the consent was the subject’s legally acceptable representative, the consent 
signer’s relationship to the study subject (eg, parent, spouse), and that the subject’s assent 
was obtained, or waived.  If assent is obtained verbally it must be documented in the source 
documents.
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If the study includes minor subjects who reach the age of majority during the study, as 
recognized under local law, they must re-consent as adults to remain in the study.  If the 
enrollment of ‘emancipated minors’ is permitted by the study age criteria, the IRB/EC, and 
local law, they must provide documentation of legal status to give consent without the 
permission of a parent or legal guardian.
The investigator, or a person designated by the investigator, will obtain written informed 
consent from each subject or the subject's legally acceptable representative, parent(s) or legal 
guardian and the subject’s assent, when applicable, before any study-specific activity is 
performed, unless a waiver of informed consent has been granted by an IRB/EC. The 
investigator will retain the original of each subject's signed consent/assent document.
12.4. Subject Recruitment
Advertisements approved by IRBs/ECs and investigator databases may be used as 
recruitment procedures.  In addition, the ongoing study may be publicized through DMD 
advocacy groups. 
Pfizer will have an opportunity to review and approve the content of any study recruitment 
materials directed to potential study subjects before such materials are used. 
12.5. Reporting of Safety Issues and Serious Breaches of the Protocol or ICH GCP
In the event of any prohibition or restriction imposed (ie, clinical hold) by an applicable 
competent authority in any area of the world, or if the investigator is aware of any new 
information that might influence the evaluation of the benefits and risks of the investigational 
product, Pfizer should be informed immediately. 
In addition, the investigator will inform Pfizer immediately of any urgent safety measures 
taken by the investigator to protect the study subjects against any immediate hazard, and of 
any serious breaches of this protocol or of ICH GCP that the investigator becomes aware of.
13. DEFINITION OF END OF TRIAL
13.1. End of Trial in a Member State 
End of trial in a Member State of the European Union is defined as the time at which it is 
deemed that a sufficient number of subjects have been recruited and completed the study as 
stated in the regulatory application (ie, clinical trial application [CTA]) and ethics application 
in the Member State.  Poor recruitment (recruiting less than the anticipated number in the 
CTA) by a Member State is not a reason for premature termination but is considered a 
normal conclusion to the study in that Member State.
13.2. End of Trial in All Other Participating Countries 
End of trial in all other participating countries is defined as last subject last visit (LSLV).
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14. SPONSOR DISCONTINUATION CRITERIA
Premature termination of this study may occur because of a regulatory authority decision, 
change in opinion of the IRB/EC, investigational product safety problems, or at the discretion 
of Pfizer.  In addition, Pfizer retains the right to discontinue development of PF-06252616 at 
any time.
If a study is prematurely terminated or discontinued, Pfizer will promptly notify the 
investigator.  After notification, the investigator must contact all participating subjects and 
the hospital pharmacy (if applicable) within 1 week.  As directed by Pfizer, all study 
materials must be collected and all CRFs completed to the greatest extent possible.
15. PUBLICATION OF STUDY RESULTS
15.1. Communication of Results by Pfizer
Pfizer fulfills its commitment to publicly disclose clinical trial results through posting the 
results of studies on www.clinicaltrials.gov (ClinicalTrials.gov), the European Clinical Trials 
Database (EudraCT), and/or www.pfizer.com and other public registries in accordance with 
applicable local laws/regulations. 
In all cases, study results are reported by Pfizer in an objective, accurate, balanced, and 
complete manner and are reported regardless of the outcome of the study or the country in 
which the study was conducted.
www.clinicaltrials.gov
Pfizer posts clinical trial US Basic Results on www.clinicaltrials.gov for Pfizer-sponsored 
interventional studies conducted in patients that evaluate the safety and/or efficacy of a Pfizer 
product regardless of the geographical location in which the study is conducted. US Basic 
Results are submitted for posting within 1 year of the primary completion date for studies in 
adult populations or within 6 months of the primary completion date for studies in pediatric 
populations. 
Primary completion date is defined as the date that the final subject was examined or 
received an intervention for the purposes of final collection of data for the primary outcome, 
whether the clinical study concluded according to the prespecified protocol or was 
terminated.
EudraCT
Pfizer posts European (EU) Basic Results on EudraCT for all Pfizer-sponsored interventional 
studies that are in scope of EU requirements.  EU Basic Results are submitted for posting 
within 1 year of the primary completion date for studies in adult populations or within 
6 months of the primary completion date for studies in pediatric populations.
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www.pfizer.com
Pfizer posts Public Disclosure Synopses (clinical study report synopses in which any data 
that could be used to identify individual patients has been removed) on www.pfizer.com for 
Pfizer-sponsored interventional studies at the same time the US Basic Results document is 
posted to www.clinicaltrials.gov.
15.2. Publications by Investigators
Pfizer supports the exercise of academic freedom and has no objection to publication by a
principal investigator of the results of the study based on information collected or generated 
by the principal investigator, whether or not the results are favorable to the Pfizer product. 
However, to ensure against inadvertent disclosure of confidential information or unprotected 
inventions, the investigator will provide Pfizer an opportunity to review any proposed 
publication or other type of disclosure of the results of the study (collectively, “Publication”)
before it is submitted or otherwise disclosed.
The investigator will provide any publication to Pfizer at least 30 days before they are 
submitted for publication or otherwise disclosed. If any patent action is required to protect 
intellectual property rights, the investigator agrees to delay the disclosure for a period not to 
exceed an additional 60 days.
The investigator will, on request, remove any previously undisclosed confidential 
information before disclosure, except for any study- or Pfizer product-related information 
necessary to the appropriate scientific presentation or understanding of the study results.
If the study is part of a multicenter study, the investigator agrees that the first publication is 
to be a joint publication covering all study sites, and that any subsequent publications by the 
principal investigator will reference that primary publication. However, if a joint manuscript 
has not been submitted for publication within 12 months of completion or termination of the 
study at all participating sites, the investigator is free to publish separately, subject to the 
other requirements of this section.
For all publications relating to the study, the institution will comply with recognized ethical 
standards concerning publications and authorship, including Section II - “Ethical 
Considerations in the Conduct and Reporting of Research” of the Uniform Requirements for 
Manuscripts Submitted to Biomedical Journals, http://www.icmje.org/index.html#authorship, 
established by the International Committee of Medical Journal Editors.
Publication of study results is also provided for in the CSA between Pfizer and the 
institution.  In this section entitled Publications by Investigators, the defined terms shall have 
the meanings given to them in the CSA.
If there is any conflict between the CSA and any Attachments to it, the terms of the CSA 
control.  If there is any conflict between this protocol and the CSA, this protocol will control 
as to any issue regarding treatment of study subjects, and the CSA will control as to all other 
issues.
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29.
Wood JC, Enriquez C, Ghugre N, et al. MRI R2 and R2* mapping accurately estimates 
hepatic iron concentration in transfusion-dependent thalassemia and sickle cell disease 
patients. Blood 2005; 106(4):1460-5.
30.
Wood JC. Magnetic resonance imaging measurement of iron overload. Curr Opin 
Hematol. 2007 May;14(3):183-90.
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Appendix 1. Columbia-Suicide Severity Rating Scale (C-SSRS), Children’s 
Baseline/Screening
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Appendix 2. Columbia-Suicide Severity Rating Scale (C-SSRS), Children’s Since Last 
Visit
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Appendix 3. Pediatric Outcomes Data Collection Instrument (PODCI)
Age 2-10-Completed by Parent
Pediatric 
Outcomes Questionnaire
Developed by: 
American Academy of Orthopaedic Surgeons
Pediatric Orthopaedic Society of North America 
American Academy of Pediatrics 
Shriner’s Hospitals 
To be completed by the parent for children 2 – 10 years old 
Based on the Version 2.0 Pediatrics-Parent/Child Outcomes Instrument 
Also commonly referred to as the PODCI ("Pediatric Outcomes Data Collection Instrument")   
Revised, renumbered, reformatted August 2005
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Today’s Date        /        /  
Thank you for completing this questionnaire!   
This questionnaire will help us to better understand your general health and any 
problems related to bone and muscle conditions. 
Your completion of this questionnaire is completely voluntary and your 
responses will be held in the strictest confidence. 
Please answer every question.  Some questions may look like others, but each 
one is different. 
There are no right or wrong answers.  If you are not sure how to answer a 
question, just give the best answer you can.  You can make comments in the 
margin.  We do read all your comments, so feel free to make as many as you 
wish. 
Your Child's Birth Date        /        /  
Your Child's Social Security Number ___________________ 
Your Social Security Number ______________________
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Some kind of problems can make it hard to do many activities, such as eating, bathing, school work, and playing with 
friends.  We would like to find out how your child is doing.  (Circle one response on each line.)   
During the last week was it easy or hard for your child to:  
Easy
A little 
hard
Very 
hard
Can't do 
at all
Too young for 
this activity
1.
Lift heavy books?
1
2
3
4
5
2.
Pour a half gallon of milk?
1
2
3
4
5
3.
Open a jar that has been opened before?
1
2
3
4
5
4.
Use a fork and spoon?
1
2
3
4
5
5.
Comb his/her hair?
1
2
3
4
5
6.
Button buttons?  
1
2
3
4
5
7.
Put on his/her coat?
1
2
3
4
5
8.
Write with a pencil?
1
2
3
4
5
9.
On average, over the last 12 months, how often did your child miss school (preschool, day care, camp, etc.) because 
of his/her health?
1.
Rarely
2.
Once a month
3.
Two or three times a month
4.
Once a week
5.
More than once a week
6.
Does not attend school, etc.
During the last week how happy has your child been with: (Circle one response on each line.)  
Very 
happy
Somewhat 
happy
Not sure
Somewhat 
unhappy
Very 
unhappy
Child is 
too young
10.
How he/she looks?
1
2
3
4
5
6
11.
His/her body?
1
2
3
4
5
6
12.
What clothes or shoes he/she can wear?
1
2
3
4
5
6
13.
His/her ability to do the same things 
his/her friends do?
1
2
3
4
5
6
14.
His/her health in general?
1
2
3
4
5
6
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During the last week, how much of the time:
(Circle one response on each line.)  
Most of 
the time
Some of 
the time
A little of 
the time
None of 
the time
15.
Did your child feel sick and tired?
1
2
3
4
16.
Was your child full of pep and energy?
1
2
3
4
17.
Did pain or discomfort interfere with your 
child's activities?
1
2
3
4
During the last week, has it been easy or hard for your child to:
(Circle one response on each line.)
Easy
A little 
hard
Very 
hard
Can't do 
at all
Too young for 
this activity
18.
Run short distances?
1
2
3
4
5
19.
Bicycle or tricycle?
1
2
3
4
5
20.
Climb three flights of stairs? 
1
2
3
4
5
21.
Climb one flight of stairs?
1
2
3
4
5
22.
Walk more than a mile?
1
2
3
4
5
23.
Walk three blocks?
1
2
3
4
5
24.
Walk one block?
1
2
3
4
5
25.
Get on and off a bus?
1
2
3
4
5
26. How often does your child need help from another person for walking and climbing? (Circle one response.)  
1  Never
2  Sometimes
3  About half the time
4  Often
5  All the time
27. How often does your child use assistive devices (such as braces, crutches, or wheelchair) for walking and climbing? 
(Circle one response.)   
1  Never
2  Sometimes
3  About half the time
4  Often
5  All the time
During the last week, has it been easy or hard for your child to:
(Circle one response on each line.)
Easy
A little 
hard
Very 
hard
Can't do 
at all
Too young for 
this activity
28.
Stand while washing his/her hands and face 
at a sink?
1
2
3
4
5
29.
Sit in a regular chair without holding on?
1
2
3
4
5
30.
Get on and off a toilet or chair?
1
2
3
4
5
31.
Get in and out of bed?
1
2
3
4
5
32.
Turn door knobs?
1
2
3
4
5
33.
Bend over from a standing position and 
pick up something off the floor?
1
2
3
4
5
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34. How often does your child need help from another person for sitting and standing? (Circle one response.)  
1  Never
2  Sometimes
3  About half the time
4  Often
5  All the time
35. How often does your child use assistive devices (such as braces, crutches, or wheelchair) for sitting and standing? 
(Circle one response.)
1  Never
2  Sometimes
3  About half the time
4  Often
5  All the time
36. Can your child participate in recreational outdoor activities with other children the same age?  
(For example: bicycling, tricycling, skating, hiking, jogging)  (Circle one response.)
1  Yes, easily
2  Yes, but a little hard
3  Yes, but very hard
4  No
If you answered “no” to Question 36 above, was your child's activity limited by: (Circle yes to all that apply)
Yes
37.
Pain?
1
38.
General Health?
1
39.
Doctor or parent instructions?
1
40.
Fear the other kids won’t like him/her?
1
41.
Dislike of recreational outdoor activities?
1
42.
Too young?
1
43.
Activity not in season?
1
44. Can your child participate in pickup games or sports with other children the same age?  
(For example: tag, dodge ball, basketball, soccer, catch, jump rope, touch football, hop scotch)
(Circle one response.)
1  Yes, easily
2  Yes, but a little hard
3  Yes, but very hard
4  No
If you answered “no” to Question 44 above, was your child's activity limited by: (Circle yes to all that apply)
Yes
45.
Pain?
1
46.
General Health?
1
47.
Doctor or parent instructions?
1
48.
Fear the other kids won’t like him/her?
1
49.
Dislike of pickup games or sports?
1
50.
Too young?
1
51.
Activity not in season?
1
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52. Can your child participate in competitive level sports with other children the same age? 
(For example: hockey, basketball, soccer, football, baseball, swimming, running [track or cross country], gymnastics, 
or dance) (Circle one response.)
1  Yes, easily
2  Yes, but a little hard
3  Yes, but very hard
4  No
If you answered “no” to Question 52 above, was your child's activity limited by: (Circle yes to all that apply)
Yes
53.
Pain?
1
54.
General Health?
1
55.
Doctor or parent instructions?
1
56.
Fear the other kids won’t like him/her?
1
57.
Dislike of pickup games or sports?
1
58.
Too young?
1
59.
Activity not in season?
1
60. How often in the last week did your child get together and do things with friends? (Circle one response.)
1  Often
2  Sometimes
3  Never or rarely
If you answered “sometimes” or “never or rarely” to Question 60 above, was your child's activity limited by: (Circle 
yes to all that apply)
Yes
61.
Pain?
1
62.
General Health?
1
63.
Doctor or parent instructions?
1
64.
Fear the other kids won’t like him/her?
1
65.
Friends not around?
1
66. How often in the last week did your child participate in gym/recess? (Circle one response.)
1  Often
2  Sometimes
3  Never or rarely
4  No gym or recess
If you answered “sometimes” or “never or rarely” to Question 66 above, was your child's activity limited by: (Circle 
yes to all that apply)
Yes
67.
Pain?
1
68.
General Health?
1
69.
Doctor or parent instructions?
1
70.
Fear the other kids won’t like him/her?
1
71.
Dislike of gym/recess?
1
72.
School not in session?
1
73.
Does not attend school?
1
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74. Is it easy or hard for your child to make friends with children his/her own age? (Circle one response.)
1  Usually easy
2  Sometimes easy
3  Sometimes hard
4  Usually hard
75. How much pain has your child had during the last week? (Circle one response.)  
1  None
2  Very mild
3  Mild
4  Moderate
5  Severe
6  Very severe
76. During the last week, how much did pain interfere with your child's normal activities (including at home, outside of the 
home, and at school)?  (Circle one response.)
1  Not at all
2  A little bit
3  Moderately
4  Quite a bit
5  Extremely
What expectations do you have for your child's treatment? 
As a result of my child's treatment, I expect my child: 
(Circle one response on each line.)
Definitely
yes
Probably
yes
Not sure
Probably
not
Definitely 
not
77.
To have pain relief.
1
2
3
4
5
78.
To look better.
1
2
3
4
5
79.
To feel better about himself/herself.
1
2
3
4
5
80.
To sleep more comfortably.
1
2
3
4
5
81.
To be able to do activities at home.
1
2
3
4
5
82.
To be able to do more at school.
1
2
3
4
5
83.
To be able to do more play or recreational 
activities (biking, walking, doing things 
with friends).
1
2
3
4
5
84.
To be able to do more sports.
1
2
3
4
5
85.
To be free from pain or disability as an 
adult.
1
2
3
4
5
86. If your child had to spend the rest of his/her life with his/her bone and muscle condition as it is right now, how would 
you feel about it? (Circle one response.)
1  Very satisfied
2  Somewhat satisfied
3  Neutral
4  Somewhat dissatisfied
5  Very dissatisfied
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