A Phase 3, Double-Blind, Placebo Controlled Multicenter Study to Determine the Efficacy and Safety of Luspatercept (ACE-536) in Adults With Transfusion Dependent Beta (B)-Thalassemia
Phase: PHASE3
Conditions: Erythrocyte Transfusion, Beta-Thalassemia
Sponsor: Celgene

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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
1
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
TITLE PAGE
A PHASE 3, DOUBLE-BLIND, RANDOMIZED, 
PLACEBO-CONTROLLED, MULTICENTER STUDY TO 
DETERMINE THE EFFICACY AND SAFETY OF 
LUSPATERCEPT (ACE-536) VERSUS PLACEBO IN 
ADULTS WHO REQUIRE REGULAR RED BLOOD 
CELL TRANSFUSIONS DUE TO BETA
(!)-THALASSEMIA
The “BELIEVE” Trial
PROTOCOL NUMBER:
ACE-536-B-THAL-001
DATE FINAL:
25 Aug 2015
Amendment #1:
21 April 2017
Amendment #2:
11 December 2018
EudraCT NUMBER:
2015-003224-31
IND NUMBER:
112562
SPONSOR NAME/ ADDRESS:
Celgene Corporation
86 Morris Avenue
Summit, NJ 07901
CONFIDENTIAL
This protocol is provided to you as an Investigator, potential Investigator, or 
consultant for review by you, your staff, and ethics committee/institutional 
review board.  The information contained in this document is regarded as 
confidential and, except to the extent necessary to obtain informed consent, 
may not be disclosed to another party unless such disclosure is required by 
law or regulations.  Persons to whom the information is disclosed must be 
informed that the information is confidential and may not be further 
disclosed by them.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
2
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
MEDICAL MONITOR / EMERGENCY CONTACT INFORMATION 
Contact Information:
Name:  
Title:  
Address:  Route de Perreux 1, 2017 Boudry, Switzerland
Phone:  
(office) or 
(mobile)
E-mail:  
Note: The back-up 24-hour global emergency contact call center should only be used if you 
are not able to reach the Clinical Research Physician(s) or Medical Monitor or designee for 
emergency calls.
Back-up 24-hour Global Emergency Contact Call Center: 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
3
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
CELGENE THERAPEUTIC AREA HEAD SIGNATURE PAGE
{See appended electronic signature page}
Signature of Celgene Therapeutic Area Head
dd mmm yyyy
Printed Name of Celgene Therapeutic Area Head and Title
By my signature, I indicate I have reviewed this protocol and find its content to be 
acceptable.  
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
4
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
SITE PRINCIPAL INVESTIGATOR SIGNATURE PAGE
Signature of Site Principal Investigator
dd mmm yyyy
Printed Name of Site Principal Investigator
Institution Name:_______________________________________
By my signature, I agree to personally supervise the conduct of this study at my study 
site and to ensure its conduct is in compliance with the protocol, informed consent, 
Institutional Review Board (IRB)/Ethics Committee (EC) procedures, instructions from 
Celgene representatives, the Declaration of Helsinki, International Conference on 
Harmonisation (ICH) Good Clinical Practices Guidelines, and local regulations 
governing the conduct of clinical studies.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
5
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
COORDINATING PRINCIPAL INVESTIGATOR SIGNATURE PAGE
Signature of Coordinating Principal Investigator
dd mmm yyyy
Printed Name of Coordinating Principal Investigator
Institution Name:_______________________________________
By my signature, I agree the protocol has been written to comply with ICH Good 
Clinical Practices guidelines and agree to offer guidance throughout the study as 
needed.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
6
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
PROTOCOL SUMMARY
Study Title
A Phase 3, double-blind, randomized, placebo-controlled, multicenter study to determine the 
efficacy and safety of luspatercept (ACE-536) versus placebo in adults who require regular red
blood cell transfusions due to beta (!)-thalassemia.
Indication
Adults who require regular red blood cell (RBC) transfusions due to !-thalassemia.
Objectives
The primary objective is:
∀
To determine the proportion of subjects treated with luspatercept plus best supportive 
care (BSC) versus placebo plus BSC who achieve an erythroid response, defined as 
≥33% reduction from baseline in transfusion burden (units RBCs / time) with a 
reduction of at least 2 units, from Week 13 to Week 24
The key secondary objectives are:
∀
To evaluate the proportion of subjects who achieve ≥33% reduction from baseline in 
transfusion burden from Week 37 to Week 48 versus placebo
∀
To evaluate the proportion of subjects who achieve ≥50% reduction from baseline in 
transfusion burden from Week 13 to Week 24 versus placebo
∀
To evaluate the proportion of subjects who achieve ≥ 50% reduction from baseline in 
transfusion burden from Week 37 to Week 48 versus placebo
∀
To evaluate the mean change from baseline in transfusion burden from Week 13 to 
Week 24
Full list with Objectives and Endpoints is provided in Section 2.
Study Design
This is a Phase 3, double-blind, randomized, placebo-controlled, multicenter study to determine 
the efficacy and safety of luspatercept (ACE-536) plus BSC versus placebo plus BSC in adults 
who require regular red blood cell transfusions due to !-thalassemia. The study is divided into 
the Screening/Run-in Period, double-blind Treatment Period, double-blind Long-term Treatment 
Period, Open-label Phase and Post-treatment Follow-up Period.
The study design is described in details in Section 3.
The study will be conducted in compliance with International Conference on Harmonisation 
(ICH) Good Clinical Practices (GCPs).
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
7
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Study Population
Subjects diagnosed with β-thalassemia (including Hemoglobin E/β-thalassemia), age ≥ 18 years,
who are regularly transfused, defined as regular transfusions of 6-20 RBC units in the 24 weeks
prior to randomization with no transfusion-free period > 35 days during that period.
A total of approximately 300 eligible subjects will be enrolled.
Length of Study
Study participation for each subject includes a Screening/Run-in Period of at least 12 weeks, a 
48-week, double-blind, placebo-controlled Treatment Period, and if applicable, followed by a 
double-blind Long-term Treatment Period and an Open-label Phase. The Post-treatment Follow-
up Period will last 156 weeks (3 years) following the last dose of IP (further details refer to
Section 3.2).
End of Treatment for each individual subject is defined as the date of the last visit in the 
Treatment Period, the Long-term Treatment Period, or in the Open-label Phase, whichever is the 
later date.
End of Study for each individual subject occurs at the time of completion of the 156 weeks of 
the Post-treatment Follow-Up Period or at the time of the end of the Open-label Phase (if 
subjects are still on treatment, as described in Section 3.2) or at the time of the End of Trial as 
defined below.
The End of Trial is defined as when all subjects initially assigned to luspatercept in the double-
blind Treatment Period, reach the maximum treatment duration of 5 years from subjects’ Dose 1 
Day 1 in the treatment period of this ACE-536-B-THAL-001 study or discontinue earlier and 
complete the 156 weeks of the Post-treatment Follow-up Period, whichever occurs later; or the 
date of receipt of the last data point from the last subject that is required for primary, secondary,
 analyses, whichever is the later date, as pre-specified in the protocol and/or 
Statistical Analysis Plan.
Study Treatments
Experimental arm.  Luspatercept clinical drug product will be provided by the Sponsor as a 
lyophilized powder in vial.  Luspatercept will be administered after reconstitution (see Section 7)
as a subcutaneous (SC) injection to subjects by the study staff at the clinical site. Subcutaneous 
injections will be given in the upper arm, abdomen, or thigh, every 3 weeks during the Treatment 
Period and during the Long-term Treatment Period, unless dose delay or treatment 
discontinuation is indicated.  Subjects will start luspatercept at 1 mg/kg dose level and can be 
dose titrated up to a maximum of 1.25 mg/kg.
Control arm. Unblinded designated site personnel at each site will be responsible for preparing 
the investigational product (see Section 7).  Placebo will be administered to subjects as an SC 
injection by the study staff at the clinical site. Subcutaneous injections will be given in the upper 
arm, abdomen, or thigh every 3 weeks during the Treatment Period and during the Long-term 
Treatment Period, unless dose delay or treatment discontinuation is indicated.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
8
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Overview of Key Efficacy Assessments
∀The primary efficacy assessment will be:
∀
Transfusion burden, calculated as units RBC per 12-week period, including the 12 
weeks prior to Dose 1 Day 1, Week 13 to Week 24, and Week 37 to Week 48.  
Additional data obtained for each transfusion will include date, volume in mL, 
hematocrit of RBCs transfused, and pre-transfusion hemoglobin level.
∀Other efficacy assessments will include:
∀
Liver iron concentration (LIC, mg/g dw) measured by magnetic resonance imaging 
(MRI)
∀
Daily dose of iron chelation therapy (ICT)
∀
Serum ferritin
∀
Total hip and lumbar spine bone mineral density (BMD) by dual energy x-ray 
absorptiometry (DXA)
∀
Myocardial iron by MRI
∀
Quality of Life using TranQol, SF36
∀
Healthcare resource utilization 
Overview of Key Safety Assessments
All subjects will be assessed for safety by monitoring adverse events (AEs), clinical laboratory 
tests, vital signs, electrocardiogram (ECG), cardiac Doppler or Multi Gated Acquisition Scan 
(MUGA), antidrug antibody (ADA) testing, and Eastern Cooperative Oncology Group (ECOG)
performance status. 
Overview of Pharmacokinetic Assessments
Population pharmacokinetics will be evaluated, and the relationship between serum drug 
exposure and clinical endpoints of interest will be explored.
Statistical Methods
The analysis populations for this protocol study are the intent-to-treat (ITT) population and the
safety population (definitions for each population are provided in Section 9).
Subjects will be randomized to receive luspatercept or placebo in a 2:1 ratio.  A stratified 
randomization schedule will be implemented.  Subjects will be stratified as described above and 
in Section 3, Overall Study Design.
Based on data from the luspatercept Phase 2 study (A536-04/A536-06), the assumed targeted 
response rate for the primary endpoint is 40% in the luspatercept group and 20% in the placebo 
group.  A total sample size of 300 (200 in the luspatercept group, 100 in placebo group) will 
have 90% power to detect the difference between the luspatercept group and the placebo group 
with a 2-sided alpha of 0.05 and assumed 10% drop-out rate for each treatment group.
Primary Efficacy Analysis The primary efficacy endpoint of this study, erythroid response, is 
defined as subjects with ≥ 33% reduction from baseline in RBC transfusion burden with a
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
9
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
reduction of at least 2 units from Week 13 to Week 24 compared to the 12-week interval prior to 
randomization for luspatercept plus BSC versus placebo plus BSC.
The efficacy analysis will be performed on the ITT population.  The primary efficacy analysis 
will be performed based on 24 weeks of data after all subjects have completed the double-blind 
24-week treatment period phase or discontinued before reaching 24 weeks of double-blind 
treatment
The primary endpoint response rate is calculated using the number of responders divided by all 
subjects in the ITT population. The Cochran Mantel-Haenszel (CMH) chi-square test will be 
performed with randomization factor as strata and 2-sided type 1 error rate of 0.05.
Secondary Efficacy Analyses The key secondary endpoints will be measured at Week 24 and 
Week 48 and will be statistically tested in a sequential order at α = 0.05 level: 
1. Proportion of subjects with erythroid response, defined as ≥ 33% reduction from baseline 
in RBC transfusion burden with a reduction of at least 2 units from Week 37 to Week 48.
2. Proportion of subjects with ≥ 50% reduction from baseline in RBC transfusion burden 
with a reduction of at least 2 units from Week 13 to Week 24.
3. Proportion of subjects with ≥ 50% reduction from baseline in RBC transfusion burden 
with a reduction of at least 2 units from Week 37 to Week 48.
4. Mean change from baseline in transfusion burden from Week 13 to Week 24.
The analyses of secondary efficacy endpoints will be performed on the ITT population. The 
results will be presented by treatment group. The statistical tests will be conducted to compare 
the treatment groups.
Detailed description of the other efficacy analyses and safety analysis is provided in Section 
9.6.3 and Section 9.7.
Interim Analysis
No interim analysis is planned.
Timing of Analyses:
Clinical Study Report for Marketing Authorization Application 
A clinical study report (CSR) for a marketing authorization application (MAA) will include 
safety and efficacy parameters at the time of the final analysis when all subjects have completed 
48 weeks of a double-blind Treatment Period or discontinued before reaching 48 weeks. With 
this cut-off date and upon database lock, the study will be unblinded. The CSR for MAA will 
include TEAEs reported for 9 weeks post last dose.
The efficacy analyses included in the CSR for MAA will be conducted on primary, secondary, 
, and safety endpoints. 
Final Clinical Study Report 
The final CSR will include efficacy and safety data at the time of the End of the Trial. (ie, when 
all subjects initially assigned to luspatercept in the double-blind Treatment Period complete the 
total treatment duration of 5 years from the subjects’ Dose 1 Day 1 in the treatment period of this 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
10
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
ACE-536-B-THAL-001 study or discontinue earlier and complete the 156 weeks of the Post-
treatment Follow-up Period, whichever occurs later.)
The final efficacy analyses will be conducted on the primary endpoint, secondary endpoints, and 
safety endpoints.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
11
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
TABLE OF CONTENTS
TITLE PAGE..............................................................................................................................1
PROTOCOL SUMMARY ..........................................................................................................6
1.
INTRODUCTION..................................................................................................19
1.1.
Disease Background - Beta-thalassemia, Pathophysiology, Diagnosis and 
Treatment ...............................................................................................................19
1.1.1.
Beta-thalassemia.....................................................................................................19
1.1.2.
Pathophysiology .....................................................................................................20
1.1.2.1.
Clinical Complications ...........................................................................................21
1.1.2.2.
Diagnosis of Beta-thalassemia ................................................................................22
1.1.2.3.
Treatment of Beta-thalassemia................................................................................23
1.2.
Compound Background - Luspatercept...................................................................26
1.2.1.
Summary of Nonclinical Studies with Luspatercept................................................26
1.2.1.1.
Pharmacology Studies.............................................................................................27
1.2.1.3.
Summary of Clinical Experience ............................................................................27
1.2.1.4.
Potential Risks of Human Use ................................................................................28
1.3.
Rationale ................................................................................................................29
1.3.1.
Study Rationale and Purpose ..................................................................................29
1.3.2.
Rationale for the Study Design ...............................................................................30
1.3.2.1.
Rationale for the Primary Endpoint.........................................................................30
1.3.2.2.
Rationale for the Secondary Endpoints ...................................................................31
1.3.3.
Rationale for Dose, Schedule and Regimen Selection .............................................33
2.
STUDY OBJECTIVES AND ENDPOINTS...........................................................35
3.
OVERALL STUDY DESIGN ................................................................................40
3.1.
Study Design ..........................................................................................................40
3.1.1.
Screening/Run-in Period.........................................................................................40
3.1.2.
Treatment Period ....................................................................................................40
3.1.3.
Long-term Treatment Period...................................................................................41
3.1.4.
Open-label Phase....................................................................................................42
3.1.5.
Post-treatment Follow-up Period.............................................................................43
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Celgene Corporation
Confidential and Proprietary
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3.1.6.
Committees ............................................................................................................43
3.2.
Study Duration for Subjects....................................................................................46
3.3.
End of Trial ............................................................................................................46
4.
STUDY POPULATION.........................................................................................47
4.1.
Number of Subjects ................................................................................................47
4.2.
Inclusion Criteria....................................................................................................47
4.3.
Exclusion Criteria...................................................................................................48
5.
TABLE OF EVENTS.............................................................................................50
6.
PROCEDURES......................................................................................................60
6.1.
Screening/Run-in Period.........................................................................................60
6.1.1.
Re-screening...........................................................................................................63
6.2.
Treatment Period ....................................................................................................63
6.2.1.
Dose Delays in Treatment Period............................................................................65
6.3.
Long-term Treatment Period...................................................................................65
6.3.1.
Dose Delays in Long-term Treatment Period ..........................................................67
6.4.
Open-label Phase....................................................................................................67
6.4.1.
Dose Delays in Open-label Treatment Period..........................................................69
6.5.
Treatment Discontinuation......................................................................................69
6.6.
Post-treatment Follow-up Period.............................................................................71
6.6.1.
Early Discontinuation Follow-up Period .................................................................72
6.7.
End of Study Visit ..................................................................................................73
6.8.
Pharmacokinetics....................................................................................................73
6.9.
Anti-Drug Antibody ...............................................................................................73
6.11.
Quality of Life........................................................................................................74
6.12.
Screen Failures .......................................................................................................74
7.
DESCRIPTION OF STUDY TREATMENTS........................................................76
7.1.
Description of Investigational Product(s)................................................................76
7.2.
Treatment Administration and Schedule .................................................................76
7.2.1.
Dose Modifications: Dose Titration, Dose Reduction and Dose Delay....................77
7.2.1.1.
Dose Titration.........................................................................................................77
7.2.1.2.
Dose Delay and Dose Reduction.............................................................................78
7.2.1.3.
Overdose ................................................................................................................80
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7.3.
Method of Treatment Assignment...........................................................................81
7.4.
Packaging and Labeling..........................................................................................81
7.4.1.
Blinding..................................................................................................................81
7.5.
Investigational Product Accountability and Disposal ..............................................82
7.6.
Investigational Product Compliance........................................................................82
8.
CONCOMITANT MEDICATIONS AND PROCEDURES....................................83
8.1.
Permitted Concomitant Medications and Procedures...............................................83
8.1.1.
General Concomitant Medication Usage.................................................................83
8.1.2.
Concomitant Medication for Anemia ......................................................................83
8.1.3.
Iron Chelation Therapy...........................................................................................83
8.1.4.
RBC Transfusions ..................................................................................................83
8.2.
Prohibited Concomitant Medications and Procedures..............................................84
8.3.
Required Concomitant Medications and Procedures................................................84
9.
STATISTICAL CONSIDERATIONS ....................................................................85
9.1.
Overview................................................................................................................85
9.2.
Study Population Definitions ..................................................................................85
9.3.
Sample Size and Power Considerations...................................................................85
9.4.
Background and Demographic Characteristics........................................................85
9.5.
Subject Disposition.................................................................................................86
9.6.
Efficacy Analysis....................................................................................................86
9.6.1.
Primary Efficacy Analysis ......................................................................................86
9.6.2.
Secondary Efficacy Analysis ..................................................................................87
9.6.2.1.
Proportion of Subjects with ≥ 33% Reduction from Baseline in RBC 
Transfusion Burden with a Reduction of at Least 2 Units from Week 37 to 
Week 48 .................................................................................................................87
9.6.2.2.
Proportion of Subjects with ≥ 50% Reduction from Baseline in RBC 
Transfusion Burden with a Reduction of at Least 2 Units from Week 13 to 
Week 24 .................................................................................................................87
9.6.2.3.
Proportion of Subjects with ≥ 50% Reduction from Baseline in RBC 
Transfusion Burden with a Reduction of at Least 2 Units from Week 37 to 
Week 48 .................................................................................................................87
9.6.2.4.
Mean Change in Transfusion Burden (RBC Units) from Week 13 to Week 
24 ...........................................................................................................................88
9.6.3.
Other Efficacy Analyses .........................................................................................88
9.6.3.1.
Mean Change in Liver Iron Concentration (LIC) ....................................................88
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
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9.6.3.2.
Mean Change in Mean Daily Dose of Iron Chelation Therapy (ICT).......................88
9.6.3.3.
Mean Change in Serum Ferritin Level ....................................................................89
9.6.3.4.
Bone Mineral Density Assessed by DXA Scan .......................................................89
9.6.3.5.
Mean Change in Myocardial Iron by MRI ..............................................................89
9.6.3.6.
Change in Quality of Life using TranQol and SF-36...............................................89
9.6.3.7.
Healthcare Resource Utilization..............................................................................90
9.6.3.8.
Duration of Transfusion Burden Reduction.............................................................91
9.6.3.9.
Time to Response ...................................................................................................91
9.6.3.10.
Transfusion Independence ......................................................................................91
9.6.3.11.
Postbaseline Transfusion Events Frequency Versus Placebo ...................................92
9.7.
Safety Analysis.......................................................................................................92
9.8.
Interim Analysis .....................................................................................................92
9.9.
Timing of Analyses ................................................................................................92
9.9.1.
Final Analysis.........................................................................................................92
9.9.1.1.
Clinical Study Report for Marketing Authorization Application..............................92
9.9.1.2.
Final Clinical Study Report.....................................................................................93
9.10.
Other Topics...........................................................................................................93
9.10.2.
Data Monitoring Committee (DMC).......................................................................93
9.10.3.
Steering Committee ................................................................................................93
10.
ADVERSE EVENTS..............................................................................................95
10.1.
Monitoring, Recording and Reporting of Adverse Events .......................................95
10.2.
Evaluation of Adverse Events.................................................................................96
10.2.1.
Seriousness.............................................................................................................96
10.2.2.
Severity/ Intensity...................................................................................................97
10.2.3.
Causality ................................................................................................................97
10.2.4.
Duration .................................................................................................................98
10.2.5.
Action Taken..........................................................................................................98
10.2.6.
Outcome.................................................................................................................98
10.3.
Abnormal Laboratory Values..................................................................................98
10.4.
Pregnancy...............................................................................................................99
10.4.1.
Females of Childbearing Potential ..........................................................................99
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523

EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
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10.4.2.
Male Subjects.........................................................................................................99
10.5.
Reporting of Serious Adverse Events....................................................................100
10.5.1.
Safety Queries ......................................................................................................100
10.5.2.
Malignancy and Pre-malignancy Reporting ..........................................................100
10.6.
Expedited Reporting of Adverse Events................................................................101
11.
DISCONTINUATIONS .......................................................................................102
11.1.
Treatment Discontinuation....................................................................................102
11.2.
End of Study.........................................................................................................102
12.
EMERGENCY PROCEDURES...........................................................................104
12.1.
Emergency Contact...............................................................................................104
12.2.
Emergency Identification of Investigational Products (Emergency 
Unblinding) ..........................................................................................................104
13.
REGULATORY CONSIDERATIONS.................................................................105
13.1.
Good Clinical Practice..........................................................................................105
13.2.
Investigator Responsibilities .................................................................................105
13.3.
Subject Information and Informed Consent...........................................................106
13.4.
Confidentiality......................................................................................................106
13.5.
Protocol Amendments...........................................................................................106
13.6.
Institutional Review Board/Independent Ethics Committee Review and 
Approval ..............................................................................................................106
13.7.
Ongoing Information for Institutional Review Board/ Ethics Committee ..............107
13.8.
Termination of the Study ......................................................................................107
14.
DATA HANDLING AND RECORDKEEPING...................................................109
14.1.
Data/Documents...................................................................................................109
14.2.
Data Management.................................................................................................109
14.3.
Record Retention..................................................................................................109
15.
QUALITY CONTROL AND QUALITY ASSURANCE......................................111
15.1.
Study Monitoring and Source Data Verification....................................................111
15.2.
Audits and Inspections..........................................................................................111
15.3.
Product Quality Complaint ...................................................................................111
16.
PUBLICATIONS .................................................................................................113
17.
REFERENCES.....................................................................................................114
18.
APPENDICES......................................................................................................117
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5.3

EDMS Doc. Number:
Luspatercept (ACE-536)
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Appendix A:  Table of Abbreviations......................................................................................117
Appendix B: ECOG Performance Status Scale........................................................................121
Appendix C:  National Cancer Institute (NCI) Common Terminology Criteria for 
Adverse Events (CTCAE) Version 4.0..................................................................122
Appendix D:  New York Heart Association - Classification of Heart Failure...........................123
Appendix E:  List with Countries within each Region .............................................................124
CCI
&(/*(1(35235,(7$5<,1)250$7,21

EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
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ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
LIST OF TABLES
Table 1:
Study Objectives.....................................................................................................35
Table 2:
Study Endpoints .....................................................................................................36
Table 3:
Table of Events.......................................................................................................50
Table 4:
Starting Dose Level with Dose Reductions and Dose Titration................................78
Table 5:
Dose Delay, Dose Reduction and Discontinuation Guidelines:................................78
Table 6:
Abbreviations and Specialist Terms......................................................................117
Table 7:
Countries Within Each Region..............................................................................124
CCI
&(/*(1(35235,(7$5<,1)250$7,21
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117
..........
.........124
12

EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
18
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
LIST OF FIGURES
Figure 1:
Pathophysiology and Clinical Complications in Beta-thalassemia...........................21
Figure 2:
Transfusion Requirement in Thalassemia................................................................23
Figure 3:
Luspatercept Schematic Representation and Mechanism of Action .........................26
Figure 4:
Overall Study Design..............................................................................................44
Figure 5:
Subject Management Decision Tree........................................................................45
CCI
&(/*(1(35235,(7$5<,1)250$7,21
45
45

EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
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ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
1.
INTRODUCTION 
This is a Phase 3, double-blind, randomized, placebo-controlled study to determine the efficacy 
and safety of luspatercept in adults with regularly transfused beta (!)-thalassemia.
1.1.
Disease Background - Beta-thalassemia, Pathophysiology, Diagnosis
and Treatment
1.1.1.
Beta-thalassemia
Beta-thalassemia, one of the most common inherited hemoglobinopathies worldwide, is due to 
autosomal mutations in the gene encoding β-globin which induce an absence or low-level 
synthesis of this protein in erythropoietic cells (Weatherall, 2001).  About 80 to 90 million 
people (~ 1.5 % of the global population) are carriers of !-thalassemia with approximately 
60,000 symptomatic individuals born annually (Modell, 2007).  The annual incidence of 
symptomatic individuals is estimated at 1 in 100,000 worldwide and 1 in 10,000 in the European 
Union (EU) (Galanello, 2010).  Incidence is highest in the Mediterranean region, the Middle 
East, and South East Asia (particularly India, Thailand, and Indonesia; this region accounts for 
approximately 50% of affected births) and incidence is increasing worldwide (eg, Europe, the
Americas and Australia) as a result of migration (Colah, 2010; Modell, 2008). 
Beta-thalassemia is characterized by a reduction of β-globin chains and a subsequent imbalance 
in globin chains (α:non-α ratio) of the hemoglobin (Hb) molecule, which results in impaired, or 
ineffective, erythropoiesis. Complications resulting from ineffective erythropoiesis are described 
in Section 1.1.2.1. Nearly 200 different mutations have been described in patients with 
!-thalassemia that affect the β-globin gene, for which patients may be either homozygous or 
compound heterozygous. Phenotypic findings, therefore, range widely in patients with slight 
impairment to complete loss of β-globin chain synthesis (Thein, 2013).  In addition to deficient 
β-globin chains, patients may also present with β-thalassemia combined with structural variants
of hemoglobin, such as HbE, leading to HbE/β-thalassemia. 
Beta-thalassemia comprises a number of different phenotypes with varying severity, including: 
∀
Transfusion-dependent thalassemia (TD): Includes patients with β-thalassemia major or
severe forms of β-thalassemia intermedia or HbE/β-thalassemia which require regular red 
blood cell transfusions 
∀
Non-transfusion dependent thalassemia (NTD): Includes patients with mild-to-moderate 
β-thalassemia intermedia or HbE/β-thalassemia who may require infrequent transfusions 
to manage the disease and its complications 
∀
β-thalassemia trait (minor): Heterozygous patients with mild, usually asymptomatic 
anemia that generally does not require treatment (excluded from the luspatercept target 
patient population)
At the severe end of the clinical spectrum are patients with β-thalassemia major with symptoms 
in infancy and reliance on regular red blood cell transfusions for survival. Each year, 
approximately 23,000 people are born with β-thalassemia major (Weatherall, 2010; Modell, 
2008). In contrast, β-thalassemia intermedia patients typically present after the age of 2 years, 
although accurate global incidence rates have not yet been established (Weatherall, 2001). 
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The severity of the disease in β-thalassemia intermedia patients also varies significantly, ranging 
from mild symptoms at clinical presentation with near normal growth, to a more severe 
phenotype characterized by early-onset anemia and abnormal physical symptoms including 
growth and developmental retardation and skeletal deformities. Some β-thalassemia intermedia 
patients who show growth retardation in childhood or begin to develop clinical complications in 
adulthood, such as thrombotic events or pulmonary hypertension, can also become transfusion-
dependent during their lifetime, regardless of whether they required regular transfusions earlier 
in life or on presentation (Guidelines for the Management of Non Transfusion Dependent 
Thalassaemia, 2013). Of note, although β-thalassemia major and intermedia describe patients 
with different levels of clinical severity, the underlying molecular and pathophysiological basis 
for the two syndromes are largely similar without intervention (Thein, 2013).
HbE/β-thalassemia is the most common form of thalassemia in India, Bangladesh and Southeast 
Asia (Colah, 2010), and occurs as a result of co-inheritance of HbE (caused by a substitution in 
the β-globin gene, leading to the production of structurally abnormal Hb which is synthesized at 
a reduced rate and behaves like a β-thalassemia allele) and a β0 allele. Clinically, 
HbE/β-thalassemia is a highly heterogeneous disease. Typically, anemia with splenomegaly 
develops from 6 to 12 months of age, with impaired growth during the first decade of the 
patient’s life (Fucharoen, 2012). Clinical symptoms vary widely; patients may be transfusion-
dependent or require only occasional or intermittent transfusions. However, these patients are 
generally managed with red blood cell (RBC) transfusion and iron chelation as needed, although 
the requirement may differ from other β-thalassemia patients.
1.1.2.
Pathophysiology
Ineffective erythropoiesis in individuals with β-thalassemia reflects the consequences of excess, 
unpaired #-globin (Cao, 2010; Sankaran, 2010).  The degree of #-globin to non-#-globin 
biosynthetic ratio is the major determinate of disease severity, rather than the underproduction of 
hemoglobin (Weatherall, 1965; Nathan, 1966; Weatherall, 2001).  Depending on the β-globin 
gene defect(s) and their interaction, β-globin production is quantitatively reduced to different 
extents whereas the synthesis of #-globin continues at normal rates, resulting in an accumulation 
of excess unmatched #-globin chains in the erythroid precursors. The free #-globin chains are 
not able to form stable tetramers.  Rather, they precipitate in the erythroid precursors forming 
inclusion bodies that damage the RBC membrane, causing premature destruction (apoptosis) of 
erythroid precursors in the bone marrow (ineffective erythropoiesis). This leads to a sequence of
events resulting in bone marrow expansion, anemia, hemolysis, splenomegaly, extramedullary 
hematopoiesis, and increased intestinal iron absorption (Figure 1). Any factor that reduces the 
degree of chain imbalance and the magnitude of #-chain excess, such as coinheritance of #-
thalassemia or an innate ability to increase fetal hemoglobin will thus ameliorate the clinical 
expression of the disease (Cappellini, 2014).
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Figure 1:
Pathophysiology and Clinical Complications in Beta-thalassemia
Source: Musallam, 2013.
1.1.2.1.
Clinical Complications
Eventually all of the pathophysiologic features of β-thalassemia can be linked to the primary 
imbalance in globin chain production and accumulation of unpaired α-globin chains within the 
developing erythrocyte, resulting in ineffective erythropoiesis which leads to anemia and a 
variety of subsequent pathophysiologic mechanisms including hemolysis, iron overload, and 
hypercoagulability which are in turn linked to clinical morbidities. The severity of the ineffective 
erythropoiesis drives all clinical complications (Musallam, 2011).
Regularly Transfused (Transfusion-Dependent) β-thalassemia 
Regularly transfused β−thalassemia is comprised of two genotypically different but 
phenotypically similar groups of patients: those with thalassemia major and those with more 
severe thalassemia intermedia. The major forms of β−thalassemia (also known as Cooley’s 
anemia) are disorders in which life can be sustained only by regular blood transfusions. These 
conditions usually result from the homozygous or compound heterozygous state for severe !-
gene mutations (β∃%.  Typically, symptoms become manifest during the first year of life, when 
the normal switch from γ−chains to β−chains does not occur. In some resource-limited settings, 
the clinical picture in patients who are untreated or poorly transfused, is characterised by growth 
retardation, pallor, jaundice, poor musculature, genuvalgum, hepatosplenomegaly, leg ulcers, 
development of masses from extramedullary hematopoiesis, and skeletal changes resulting from 
expansion of the bone marrow (Guidelines for the Management of Transfusion Dependent 
Thalassemia, 2014, Galanello, 2010). Many children who are adequately transfused and are fully 
compliant with iron chelation therapy develop normally, enter puberty and become sexually
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
22
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
mature. The adult population of TD patients suffers from the side effects of chronic transfusions, 
namely transfusion-associated infections, (particularly hepatitis B and C and in some populations 
human immunodeficiency virus [HIV]), and organ damage due to iron overload (including liver, 
heart, and endocrine glands) (Galanello, 2010; Cappellini, 2014). 
Some β-thalassemia intermedia patients who show growth retardation in childhood or begin to 
develop clinical complications in adulthood, such as thrombotic events or pulmonary 
hypertension, may also require regular transfusions and become transfusion-dependent during 
their lifetime, regardless of whether they required regular transfusions earlier in life or on 
presentation (Guidelines for the Management of Non Transfusion Dependent Thalassaemia, 
2013).
The primary cause of death in adult TD patients remains cardiac events due to iron overload
mainly caused by RBC transfusions (Rund, 2005; Voskaridou, 2012) although recent studies 
show that liver disease is also becoming a leading cause of morbidity and mortality (Voskaridou,
2012).
Many aspects of heart failure in these patients are still poorly understood. It is clear that it is 
multifactorial involving chronic anemia, iron overload, myocarditis, pericarditis and probably 
other mechanisms. Furthermore, genetic modifiers acting at a tertiary level may impact the 
complications of thalassemia (Cappellini, 2014).
1.1.2.2.
Diagnosis of Beta-thalassemia 
Beta-thalassemia include three forms of increasing severity.  Beta-thalassemia minor (or trait) is 
due to the inheritance of one mutant β-globin gene and may result in microcytic anemia.  The 
other two conditions, β-thalassemia intermedia and β-thalassemia major, are clinically relevant 
requiring medical management.  The most severe form, β-thalassemia major, results from 
homozygosity or compound heterozygosity for a mutant β-globin allele (β0/β0, β+/β+, β0/ β+, 
β0/HbE, β+/HbE).  Beta-thalassemia intermedia phenotype can result from compound 
heterozygosity of milder mutations (β0 or β+, as well as with Hb variants including HbE), or 
coinheritance of two severe ! mutations with either #-thalassemia or determinants that increase 
fetal hemoglobin production. Patients who are heterozygous for a β-globin mutation can have 
symptomatic thalassemia if they co-inherit duplication of the α-globin gene(s). The diagnosis of 
β-thalassemia can be confirmed by the presence of the β-thalassemia trait in both parents (Thein, 
2013).
Beta-thalassemia major and β-thalassemia intermedia have no specific molecular correlate but 
rather encompass a wide spectrum of clinical and laboratory abnormalities.  Patients referred to 
as having !-thalassemia major are usually those who come to medical attention in infancy and 
subsequently require regular transfusions to survive.  Those who present with symptoms later in 
their life or who seldom need transfusions early in life are said to have !-thalassemia intermedia. 
Hematologic findings include microcytic, hypochromic anemia and elevated HbA2 and fetal 
hemoglobin [HbF].  Note that !-thalassemia intermedia patients can present as a severe 
phenotype and may require regular transfusions later in life in order to better manage certain 
complications of the disease.
The spectrum of transfusion requirements in various thalassemia forms is illustrated in Figure 2
below (Musallam, 2013):
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
23
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Figure 2:
Transfusion Requirement in Thalassemia
1.1.2.3.
Treatment of Beta-thalassemia
Current treatment options for !-thalassemia are limited; transfusions remain the mainstay of 
treatment. In regularly transfused patients, iron chelation therapy is required to treat and/or
prevent transfusional iron overload-related complications.  In non-transfusion dependent 
patients, the treatment strategy is focused on iron overload-related complications, as well as 
complications related to the disease itself.  An overview of treatment options for !-thalassemia is 
presented below.
1.1.2.3.1. Transfusion
As mentioned, β-thalassemia transfusion-dependent patients require regular transfusions, which 
can result in a number of subsequent complications (Guidelines for the Management of 
Transfusion Dependent Thalassemia, 2014). These include infections, iron overload and related 
complications, such as cardiac, liver and endocrine problems, and ultimately, death due to organ 
failure. In addition, alloimmunization may occur, whereby the recipient mounts an immune 
response to donor antigens, resulting in various clinical consequences. Alloimmunization is more
common in children who begin transfusion therapy after 1 to 3 years of age than in those who
begin transfusion therapy earlier. Some evidence also suggests that new alloantibodies develop 
more frequently after splenectomy (Thompson, 2011). The use of extended antigen matched 
donor blood is effective in reducing the rate of alloimmunization.
1.1.2.3.2. Iron Overload and Iron Chelation Therapies
In patients with β-thalassemia requiring regular transfusions, iron overload occurs mainly as a 
result of accumulation of iron from transfusions and, to a lesser extent, increased intestinal 
absorption. In contrast, in non-transfusion dependent β-thalassemia patients, non-transfusional
iron overload is present due to increased intestinal absorption of iron secondary to ineffective 
erythropoiesis and suppression of hepcidin (Gardenghi, 2007; Ginzburg, 2011).
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
24
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
The main goal of iron chelation therapy is to maintain safe levels of body iron at all times. Once 
iron overload has occurred, removal of stored iron is slow and inefficient, because only a small 
proportion of body iron is available for chelation at any given time (Guidelines for the 
Management of Transfusion Dependent Thalassemia, 2014).
The standard chelation therapy for more than 40 years was deferoxamine (DFO).  Unfortunately, 
compliance with the rigorous requirements of daily subcutaneous infusions was a serious 
limiting factor and in noncompliant patients life expectancy was not different from that in the 
pre-DFO era (Cappellini, 2014, Gabutti, 1996). Subsequently, 2 oral iron chelators have been 
marketed including: deferiprone (DFP) and deferasirox (DFX). A potential benefit of combined 
DFO/DFP therapy has been observed for patients with very high levels of cardiac iron 
(Cappellini, 2014, Tanner 2007).
Deferasirox (DFX) has been shown to be safe and effective in removing excess iron from 
different organs including the heart (Cappellini, 2014). However some patients do not respond to 
DFX at maximally tolerated doses.  Deferasirox use is individualized according to age and
compliance history to previous chelation, and monitored using ferritin levels, and measurements 
of cardiac and liver iron by MRI (Guidelines for the Management of Transfusion Dependent 
Thalassemia, 2014).
1.1.2.3.3. Splenectomy
Hypersplenism may occur as a result of large numbers of cells being pooled and destroyed in the 
spleen’s reticulo-endothelial system, and hemodilution because of an increased plasma volume. 
Therefore, spleen size is carefully monitored in all patients with β-thalassemia (Cappellini, 
2014a). Many patients with β-thalassemia major require splenectomy. Good clinical management 
may delay or prevent hypersplenism, reducing the need for splenectomy (Piga, 2011).  As 
abnormalities of platelets and red blood cells become more prominent following splenectomy, 
patients are at an increased risk of thrombotic and vascular events, with an associated increased 
mortality rate. (Cappellini, 2000; Taher, 2006).
1.1.2.3.4. Fetal Hemoglobin (HbF) Induction
Fetal hemoglobin is made up of alpha and gamma chains and is the predominant hemoglobin in 
RBCs of patients with severe β-thalassemia.  Increasing levels of fetal hemoglobin (HbF) can 
theoretically ameliorate the severity of β-thalassemia by reducing the amount of free alpha-
globin.  
Hydroxyurea (or hydroxycarbamide) is the fetal hemoglobin inducer for which most data in 
NTD subjects have been generated (Guidelines for the Management of Non Transfusion 
Dependent Thalassaemia, 2013). Hydroxyurea use in TD subjects has never been systematically 
studied (Guidelines for the Management of Transfusion Dependent Thalassemia, 2014). The 
exact mechanisms by which hydroxyurea induces fetal hemoglobin production are not fully 
understood. A cytotoxic effect resulting in stress erythropoiesis with increased fetal hemoglobin 
levels is most commonly proposed (Mabaera, 2008). However, such cytotoxic agents are
associated with toxicity with long-term use, and are potentially mutagenic. 
There is a lack of randomized clinical trials investigating the efficacy of hydroxyurea treatment 
on decreasing transfusion burden and it is not approved to treat β-thalassemia. Though data are 
available from a large number of single-arm trials or retrospective analyses of hydroxyurea 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
25
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
therapy, patient numbers are small and results have not been consistently reproduced (Musallam 
2013; Cappellini, 2014a).  
1.1.2.3.5. Hematopoietic Stem-Cell Transplantation
Early, allogeneic hematopoietic stem cell transplantation (HSCT) has curative potential. In adult 
patients who received allogeneic HSCT from human leukocyte antigen (HLA)-identical donors, 
the curative potential is reported to be from approximately 60% (Olivieri, 1999) to 73% 
(Angelucci, 2008). However, this option is limited by availability of appropriate donors and by 
risks associated with the bone marrow transplant procedure. Additionally, HSCTs are more 
commonly performed in patients under 21 years of age (preferably under 16 years) than in older 
patients (Sabloff, 2011).
1.1.2.3.6. Erythropoiesis-stimulating Agents (ESA)
Erythropoiesis-stimulating agents are not indicated for and are not commonly used for the 
treatment of β-thalassemia. The anemia and resulting hypoxia in β-thalassemia leads to already
increased in serum erythropoietin (EPO) levels in an attempt to compensate for the reduced 
oxygen carrying capacity.  As EPO binds to receptors on the earliest erythroid progenitors, the 
use of ESAs may further increase erythroid mass and the production of abnormal RBCs (Fibach, 
2014).  Thus, treatment with ESAs is associated with potential risks, including erythroid 
expansion, increased iron absorption, and extramedullary hematopoiesis (Rachmilewitz, 1998).
1.1.2.3.7. Summary of Current Treatments
Transfusions are still the mainstay of therapy. Transfusions are associated with iron overload and 
other complications. Transfusion therapy leads to poor quality of life (QoL) due to time lost, and 
it is associated with costs and requirement for iron chelation therapies (which are also associated 
with adverse events). Hematopoietic stem cell transplantation from an identical family donor is 
an alternative treatment option for children with thalassemia and the only one which can result in 
cure (SCCCAT, 2008). However, this option is limited by availability of appropriate donors and 
by risks associated with the bone marrow transplant procedure.
Other than iron chelation agents with indications for the treatment of chronic iron overload, there 
is no approved drug therapy specifically for the treatment of patients with !-thalassemia.
Additionally, there is limited use of currently available pharmacological therapies. For example, 
cytotoxic agents can inhibit erythroid proliferation, but are associated with toxicity with long-
term use, and are potentially mutagenic. As such, hydroxyurea is rarely used for the chronic 
treatment of β-thalassemia. ESAs have minimal therapeutic and may pose additional risks to β-
thalassemia patients. Patients require many other therapies to treat the consequence of anemia 
such as folic acid supplements and medication for osteoporosis. 
Given the current lack of safe and effective drug treatments, there is significant unmet medical 
need for the development of new therapies that specifically address the underlying 
pathophysiology of !-thalassemia including ineffective erythropoiesis and anemia, to decrease 
transfusions and prevent associated complications.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
26
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
1.2.
Compound Background - Luspatercept
Luspatercept (ACE-536) is a recombinant fusion protein consisting of a modified form of the 
extracellular domain (ECD) of the human activin receptor type IIB (ActRIIB) linked to the 
human immunoglobin G 1 (IgG1) Fc domain (Figure 3A). The ActRIIB receptor and its ligands 
are members of the transforming growth factor-β (TGF-β) superfamily, a group of proteins 
involved in the development, differentiation, and/or maturation of various tissues. No species 
differences have been described in the ligand-receptor interactions among members of the TGF-β 
family as the ligands and receptors are highly conserved across species (Massague, 1998).  Thus, 
observations from pharmacology studies of luspatercept or its murine ortholog RAP-536 in 
animal models provide significant insight into the potential of luspatercept to treat human 
disease. 
Members of the TGF-β ligands through their binding to activin receptors, are involved in 
modulating the differentiation of late-stage erythrocyte precursors (normoblasts) in the bone 
marrow. In nonclinical experiments, luspatercept has been shown to bind with high affinity to 
some TGF-β ligands (eg, GDF11, GDF8, BMP6 and activin B) 
 
. The mechanism of action of luspatercept is independent 
from that of EPO (Suragani, 2014a). While EPO stimulates proliferation and differentiation of 
early erythroid progenitors, luspatercept promotes stimulation of the later, maturation phase of 
erythroblast differentiation and maturation in the bone marrow (Figure 3B and Section 1.3).
During normal erythropoiesis, GDF11 appears to inhibit differentiation and maintain the survival 
of immature erythroid progenitors, but its expression is decreased as cells mature, and thus its 
effect is transient. In the thalassemia model, defects in erythroid differentiation led to an 
accumulation of GDF11 expressing cells that maintained their own survival (Dussiot, 2014). 
Recent studies (Dussiot, 2014; Suragani, 2014a) identified GDF11 as a regulator of 
erythropoiesis and showed that its inhibition in mouse models of anemia with ineffective 
erythropoiesis restores normal erythropoietic differentiation and improves anemia.
Figure 3:
Luspatercept Schematic Representation and Mechanism of Action
A 
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1.2.1.
Summary of Nonclinical Studies with Luspatercept
A brief summary of key findings from pharmacology and toxicology studies is provided below. 
Please refer to the Investigator’s Brochure (IB) for detailed information concerning the available 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
27
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
pharmacology, toxicology, drug metabolism, clinical studies, and adverse event profile of the 
investigational product (IP). The most recent version of the luspatercept IB should be reviewed 
prior to initiating the study.
1.2.1.1.
Pharmacology Studies 
In vitro and in vivo nonclinical pharmacology studies have been conducted with luspatercept or 
its murine ortholog, RAP-536. The RAP-536 molecule has the same ECD as luspatercept, but 
contains a murine IgG Fc domain in place of the human IgG Fc. The RAP-536 ortholog is 
intended to be less immunogenic in rodent species and therefore permits the conduct of longer 
term pharmacology studies in rodents without the confounding influence of immune reactivity
(Suragani, 2014a).
The Hbb major-/- transgenic mouse was used to test RAP-536 in a model of β-thalassemia. This 
model represents human β-thalassemia intermedia, which is characterized by severe anemia, 
failure of erythroid differentiation, increased apoptosis of erythroid precursors, erythroid 
hyperplasia, splenomegaly and iron overload. Treatment with RAP-536 led to significant 
improvement in hematological parameters, including RBC and hemoglobin. Further effects of 
treatment included decreased reticulocytes, red cell distribution width, EPO, bilirubin, RBC 
inclusion bodies, reactive oxygen species, serum ferritin, liver iron concentration (LIC), and 
spleen size, as well as increased hepcidin and bone mineral density, and improvements in RBC 
morphology (Suragani, 2014). 
Additional information regarding the pharmacological effects of luspatercept is summarized in 
the current version of the luspatercept IB.
 
 
 
 
1.2.1.3.
Summary of Clinical Experience 
One Phase 1 trial with healthy postmenopausal women has been completed (Attie, 2014). Two
Phase 2 studies with β-thalassemia are ongoing:
∀
Study A536-04 is entitled “A Phase 2, Open-Label, Ascending Dose Study to 
Evaluate the Effects of ACE-536 in Patients with β-Thalassemia”. 
∀
Study A536-06 is entitled “An Open-Label Extension Study to Evaluate the Long-
Term Effects of ACE-536 in Patients with β-Thalassemia Previously Enrolled in 
Study A536-04”. 
 
 
  
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
28
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
 A reduction (> 33%) in RBC transfusion 
burden was observed in the majority of the transfusion-dependent β-thalassemia subjects.  
Luspatercept was well tolerated at the tested dose levels (0.2 to 1.25 mg/kg SC every three 
weeks).
Additional information regarding clinical experience with luspatercept is summarized in the 
current version of the luspatercept IB.
1.2.1.4.
Potential Risks of Human Use 
Increases in hematologic parameters (RBC, hemoglobin, hematocrit, reticulocytes) are expected 
pharmacologic effects of luspatercept treatment. Increases in systolic and diastolic blood 
pressures may occur in concert with increases in hemoglobin values. Excessive or rapid increases 
in hemoglobin or blood pressure may occur and will be monitored. Dose modifications rules for 
individual subjects and dose titration/reduction rules will be utilized to minimize risks associated 
with increased RBC parameters. 
Adverse events considered probably or possibly related to study drug that were reported in the 
Phase 1 study in healthy volunteers included injection site hemorrhage and injection site macule. 
As of 07 July 2016, adverse events reported regardless of causality in the ongoing Phase 2 
studies in MDS and β-thalassemia included bone pain, headache, asthenia, myalgia, arthralgia, 
nasopharyngitis, pyrexia, oropharyngeal pain, diarrhea, fatigue, musculoskeletal pain, cough and 
influenza.
 
  Luspatercept must 
not be given to a pregnant woman or a woman who intends to become pregnant.  If a woman 
becomes pregnant while taking luspatercept, the medication must be stopped immediately.  
If luspatercept is taken during pregnancy, a teratogenic effect in humans cannot be ruled out.  In 
addition, since it is unknown if luspatercept is excreted in breast milk, breastfeeding is prohibited 
in all protocols.
 
  
As with all biologics, there is the potential for antidrug antibodies (ADA) that can be associated 
with increased drug clearance and hypersensitivity reactions. 
 
Please refer to the Investigator’s Brochure (IB) for additional information regarding findings 
from toxicology studies.
 
Safety will be monitored 
closely through adverse event (AE) reporting, clinical laboratory tests, vital signs, and physical 
examinations, and ongoing review of unblinded data by an external DMC. 
A comprehensive review of luspatercept, as well as details regarding the information 
summarized above, is provided in the IB. The most recent version of the luspatercept IB should 
be reviewed prior to initiating the study.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
29
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
1.3.
Rationale
1.3.1.
Study Rationale and Purpose
In β-thalassemia, the imbalance in globin chain production and accumulation of unpaired α-
globin chains within the developing erythroblast results in ineffective erythropoiesis, which leads 
to anemia. The unbound free α-globin chains precipitate in erythroid precursors and these 
precipitates are associated with the production of reactive oxygen species (ROS), which induce 
the death of erythroid precursors at the polychromatophilic stage (Weiss, 2009; Ribeil, 2013), 
and thus results in a suboptimal production of mature RBCs (ineffective erythropoiesis), a 
hallmark of β-thalassemia (Ginzburg, 2011). It has been proposed that members of the TGF-β 
superfamily participate in the proliferation and differentiation of erythroid progenitors (Dussiot, 
2014).
It has been demonstrated that RAP-536 (the murine ortholog of luspatercept), a modified 
ActRIIB ligand trap, can alleviate anemia in a transgenic mouse model of β-thalassemia (Hbb
th1/th1 mice) in part by promoting differentiation of later-stage erythroid precursors and 
reducing hemolysis, effects likely due to reduced α-globin aggregates in erythrocytes and 
decreased ROS in erythroid precursors and peripheral erythrocytes. In addition to improving 
these fundamental features of the disease, RAP-536 treatment in Hbb th1/th1 mice produced 
beneficial effects on several interrelated disease complications, such as decreased reticulocytes, 
red cell distribution width, EPO, bilirubin, RBC inclusion bodies, reactive oxygen species, serum 
ferritin, LIC, and spleen size, as well as increased hepcidin and bone mineral density, and 
improvements in RBC morphology (Suragani, 2014).
Interim data from the ongoing Phase 2 clinical trial with luspatercept in β-thalassemia subjects
(A536-04) demonstrated that 75% of subjects treated with luspatercept for 3 months at dose 
levels of 0.8 to 1.0 mg/kg met the primary efficacy endpoint, notably (i) increase in hemoglobin 
≥1.5 g/dL for ≥ 2 weeks in 50% of NTD subjects, and (ii) decrease in RBC transfusion burden 
≥20% (median 67%, ranging from 43 to 100%) in 100% of evaluable TD subjects. In addition, 
liver iron concentration and serum ferritin decreased in both TD and NTD subjects, and rapid 
healing of leg ulcers was observed in 3 of 3 subjects. Furthermore, the safety profile was 
favorable with no related serious adverse events. These data strongly support further evaluation 
of luspatercept in subjects with β-thalassemia.
The standard of care for transfusion-dependent β-thalassemia subjects involves regular blood 
transfusions, usually administered every two to four weeks, to maintain a pre-transfusion 
hemoglobin level of 9 to 10.5 g/dL, for the purpose of suppressing the bone marrow. There is no 
approved drug therapy specifically for the treatment !-thalassemia.  Iron chelation agents are 
approved for the treatment of chronic iron overload which is primarily due to transfusions in 
transfusion-dependent patients for the treatment of chronic iron overload.
Considering the current lack of safe and effective drug therapies, this regularly-transfused 
population would benefit from an active drug that specifically addresses the underlying 
pathophysiology of !-thalassemia including ineffective erythropoiesis, and anemia, and to reduce 
the dependence on transfusion therapy, thus reducing both the risk of complications from β-
thalassemia and transfusions therapy, including iron overload.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
30
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Luspatercept has the potential to provide benefit in a variety of conditions in which ineffective 
erythropoiesis contributes significantly to anemia and overall disease morbidity, including β-
thalassemia.  The ability of luspatercept to rapidly increase and sustain Hb concentrations in 
anemic patients supports the clinical development of luspatercept for the treatment of patients 
with anemia associated with β-thalassemia.
1.3.2.
Rationale for the Study Design
The current study is a Phase 3, multicenter, randomized, double-blind, placebo-controlled, study 
to compare the efficacy and safety of luspatercept plus BSC versus placebo plus BSC in adult 
subjects with regularly transfused β-thalassemia. Subjects are required to be diagnosed with β-
thalassemia (including Hemoglobin E/β-thalassemia), aged ≥ 18 years and be regularly 
transfused.  Transfusion dependence is defined in this study as receiving 6-20 RBC units during
the 24 weeks prior to randomization and no transfusion-free period for > 35 days. The minimum 
of 6 units has been defined based on potential transfusion practices, including a minimum of 1 
unit every 4 weeks (or 6 units/24 weeks), which may be observed in countries with limited blood 
supply, as per feedback received from investigators. The maximum of 20 units in the 24 weeks
prior to randomization was determined based on the clinical data from Phase 2 studies with 
luspatercept in β-thalassemia, in which no subjects with transfusion burden >20 units/24 weeks 
achieved the planned primary endpoint for response in this Phase 3 study.
The multicenter nature of the study provides assurance that the results are likely to have general 
applicability. The design of this study (ie, randomized, double-blinded, placebo-controlled, and 
parallel-group) will eliminate bias in assignment of the IP or in data interpretation.
Given the lack of agents globally approved and/or used in !-thalassemia to attenuate ineffective 
erythropoiesis and/or to correct anemia, the standard of care is largely supportive with RBC 
transfusion and splenectomy.  There may be some subjectivity with regard to deciding when and 
how much to transfuse a patient in a particular clinical situation.  For this reason, the Sponsor 
plans to use saline-placebo control as the comparator in the proposed study in regularly
transfused β-thalassemia subjects, as well as implement clear guidelines regarding when to 
administer transfusions while on treatment, based on the pre-treatment transfusion history for 
each patient (refer to Section 8.1.4).
There will be unblinded designated site personnel at each site responsible for preparing the IP.  
All other site personnel, including the Investigators and monitors, will be blinded to treatment 
assignment during the study.
Best supportive care is not a treatment regimen in this study.  However, it may be used in 
combination with the investigational product as deemed necessary.  Best supportive care in both 
treatment arms may include RBC transfusion, iron-chelating agents, use of antibiotic, antiviral 
and antifungal therapy, and/or nutritional support, thus the risk of not providing subjects with 
appropriate care is minimized.
1.3.2.1.
Rationale for the Primary Endpoint
The primary endpoint of the study is the proportion of subjects with erythroid response, defined 
as ≥ 33% reduction from baseline in RBC transfusion burden with a reduction of at least 2 units 
from Week 13 to Week 24. To mitigate any potential bias should subjects in the control arm drop 
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.3.2.1

EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
31
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
out early due to lack of response, the primary efficacy analysis will be measured at 13-24 weeks.  
Importantly, subjects will continue to be followed on their assigned treatment, in a blinded 
manner, for 48 weeks (see Section 3) to generate longer-term efficacy and intermediate term 
safety information.
A 33% or greater reduction in transfusion burden is considered to be clinically meaningful for 
patients regularly transfused based on the decrease in the transfusional iron accumulation and 
related complications. We have estimated that a patient who requires 2 RBC units every 4 weeks 
pretreatment and reduced frequency to 2 units every 6 weeks will benefit from a reduction in 
transfusional iron intake of approximately 1700 mg/year, based on an estimated 200 mg 
iron/RBC unit (Cohen, 2008; Porter, 2001). In a 50 kg patient, this reduction of transfusional 
iron of 1700 mg/year would translate into a reduction of liver iron concentration of ~3 mg/g dry 
weight (Angelucci, 2000), which has been considered a clinically meaningful change in recent 
iron chelation studies in β-thalassemia populations (Cappellini, 2006; Taher, 2012). Reduced 
transfusional iron can also lead to empirical reduction in iron chelation therapy dose (Cohen, 
2008), thus reducing the risks and costs associated with that therapy. 
To further evaluate the benefit for patients, we have included as a key secondary endpoints a 
≥50% reduction in RBC transfusion burden at 13-24 weeks.  To address the durability of 
response, secondary endpoints are including that evaluate reduction in transfusion burden 
measured at 37-48 weeks of treatment.
Reduced survival in regularly transfused thalassemia patients is largely due to iron overload 
complications in major organs, in particular involving the heart and liver. In addition, blood 
transfusion exposes patients to a variety of risks (eg, alloimmunization, infection), and may be 
affected by limited access to safe blood products in developing countries, where the majority of 
the β-thalassemia patients reside. These present major challenges in managing patients requiring 
regular/frequent transfusions. Therefore, reduction in transfusion burden is expected to provide 
numerous benefits for these patients, including improvement in quality of life and a reduction in 
the need for iron chelation therapy.
Clear guidelines regarding when to alter either the frequency or number of RBC units transfused 
are specified in the protocol, with the goal of maintaining or improving the previously 
established pre-transfusion hemoglobin threshold for each patient (refer to Section 8.1.4). This 
will decrease the subjectivity with respect to transfusions and provide an accurate measure of 
change in transfusion requirement.
1.3.2.2.
Rationale for the Secondary Endpoints
The proposed secondary endpoints, including safety, other measures of efficacy and 
pharmacokinetics, are included in Section 2.
Safety Assessments:
Safety will be assessed by evaluation of AEs and laboratory data. Adverse events and abnormal 
laboratory value severity will be graded using the National Cancer Institute (NCI) Common 
Terminology Criteria for Adverse Events (CTCAE) (version 4.0, current active minor version).
All grades and Grade 3/4 treatment-emergent adverse events (TEAEs), related to investigational 
product, and serious TEAEs will be summarized separately.  
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
32
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Reduction in Transfusion Burden by ≥ 33% From Baseline From Week 37 to Week 48:
Subjects will be followed for 48 weeks in a blinded manner to generate longer-term efficacy 
data.
Reduction in Transfusion Burden by ≥ 50% From Baseline:
To further evaluate the benefit for subjects, key secondary endpoints will include a ≥50% 
reduction in RBC transfusion burden for weeks 13-24, as well as for weeks 37-48. 
Iron Overload:
In β-thalassemia patients who are regularly transfused, iron overload occurs mainly as a result of 
accumulation of iron from transfusions and, to a lesser extent, increased intestinal absorption of 
iron due to hepcidin suppression. 
It is generally accepted that LIC is the most reliable indicator of body iron overload (Guidelines 
for the Management of Transfusion Dependent Thalassaemia, 2014) and an indicator of risk for 
cardiac iron overload. Normal LIC values are up to 2 mg/g dry weight (dw). Patients with LIC 
of ≥3 mg/g dw are considered to have iron overload (Guidelines for the Management of Non 
Transfusion Dependent Thalassaemia, 2013; Guidelines for the Management of Transfusion 
Dependent Thalassaemia, 2014). At ≥ 7 mg/g dw there is an increased risk of iron induced 
complications; ≥ 15 mg/g dw is associated with an increased risk of cardiac disease and early 
death in thalassemia patients with transfusional iron overload (Olivieri, 1997). A 20% reduction 
is considered clinically meaningful and a 30% decrease over 1 year was agreed to be clinically 
relevant by the study Steering Committee for the Thalassa trial for iron chelation therapy (Taher, 
2010).
Iron Chelation Therapy Use: 
Iron chelation therapy (ICT) is essential to survival of heavily transfused patients; however, it is 
frequently associated with adverse events.  It has been reported that compliance with the rigorous 
requirements of daily subcutaneous infusions of deferoxamine (DFO) was a serious limiting 
factor and that life expectancy for noncompliant patients was not different from that in the pre-
DFO era (Cappellini, 2014, Gabutti, 1996).
Although two oral iron chelators are now available in various regions, deferiprone (DFP) and 
deferasirox (DFX), some patients do not respond to treatment at maximally tolerated doses 
(Guidelines for the Management of Transfusion Dependent Thalassaemia, 2014).  Reducing 
transfusion burden will very likely reduce ICT daily dosage requirements and possibly the need 
for ICT at all, which will provide a number of benefits to the patients.
Quality of Life:
TranQol and Short Form (SF)-36, questionnaires will be used to assess the impact of the 
treatment on the quality of life in patients with β-thalassemia. SF-36 has been used in several 
prior studies in the β-thalassemia population and is well known to Investigators from multiple 
countries. TranQol has been developed for and validated in patients with transfusion-dependent 
β-thalassemia (Klaassen, 2014).  It contains questions that specifically pertain to QoL issues 
related to transfusion burden in thalassemia patients, such as impact on school or work activities. 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
33
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Healthcare Resource Utilization:
The economic objective of this study is to characterize medical resource utilization among 
subjects treated with luspatercept as compared to subjects receiving placebo treatment. To
facilitate this aim, medical healthcare resource utilization (HRU) data will be collected.  In 
addition, the number of transfusion events will be evaluated, as these relate directly to hours or 
days devoted to receiving RBC transfusions that can impact patients’ quality of life.
1.3.3.
Rationale for Dose, Schedule and Regimen Selection
The starting dose level of 1 mg/kg and the maximum dose level of 1.25 mg/kg are based on 
clinical data from the ongoing Phase 2 A536-04 and A536-06 studies, where the increase in 
hemoglobin from baseline was maintained better with 1.0 mg/kg compared to lower dose levels, 
and 1.25 mg/kg was found to be safe and well tolerated.
Selection of the dosing schedule is based on the observed duration of the luspatercept effect on 
hemoglobin response as well as pharmacokinetic parameters for luspatercept in β-thalassemia
patients.  
 
 
 
Additional information regarding these clinical studies is summarized in the current version of 
the luspatercept IB.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
34
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
 
 
  
 
 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
35
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
2.
STUDY OBJECTIVES AND ENDPOINTS
Table 1:
Study Objectives
Primary Objective
The primary objective of the study is:
∀To determine the proportion of subjects treated with luspatercept plus BSC versus placebo plus 
BSC who achieved erythroid response, defined as ≥ 33% reduction from baseline in transfusion 
burden (units RBCs / time) with a reduction of at least 2 units, from Week 13 to Week 24.
Secondary Objective(s)
The secondary objectives are:
∀To evaluate the proportion of subjects who achieve ≥ 33% reduction from baseline in transfusion 
burden from Week 37 to Week 48 versus placebo
∀To evaluate the proportion of subjects who achieve ≥ 50% reduction from baseline in transfusion 
burden from Week 13 to Week 24 versus placebo
∀To evaluate the proportion of subjects who achieve ≥ 50% reduction from baseline in transfusion 
burden from Week 37 and Week 48 versus placebo
∀To evaluate the mean change from baseline in transfusion burden from Week 13 to Week 24
∀To evaluate the mean change from baseline in liver iron concentration (LIC) versus placebo
∀To evaluate the mean change from baseline in mean daily dose of iron chelation therapy (ICT) 
used versus placebo
∀To evaluate the mean change from baseline in serum ferritin versus placebo
∀To evaluate the effect of luspatercept on osteoporosis/osteopenia, total hip and lumbar spine
measured by bone mineral density versus placebo
∀To evaluate mean change from baseline in myocardial iron versus placebo
∀To evaluate mean change from baseline in QoL assessments, such as TranQol and SF-36, versus 
placebo
∀To evaluate the effect of luspatercept on healthcare resource utilization versus placebo
∀To evaluate the proportion of subjects who are transfusion independent for ≥ 8 weeks versus 
placebo
∀To evaluate the duration of reduction in transfusion burden or transfusion independence
∀To evaluate the time to erythroid response
∀To evaluate the post-baseline transfusion events frequency versus placebo
∀To evaluate the population pharmacokinetics (PK) of luspatercept in subjects with !-thalassemia
∀To evaluate the safety and immunogenicity of luspatercept versus placebo 
 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
36
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Table 2:
Study Endpoints
Endpoint
Name
Description
Time of Endpoint Measurement
Timeframe
24 weeks
48 weeks
Long -Term 
Primary 
Endpoint
∀
Proportion of subjects with hematological 
improvement, defined as ≥ 33% reduction 
from baseline in RBC transfusion burden with 
a reduction of at least 2 units from Week 13 to 
Week 24 compared to the 12-week interval 
prior to randomization for luspatercept plus 
BSC versus placebo plus BSC.
Number of RBC units 
transfused from Week 13 to 
Week 24, and in the 12 weeks 
prior to randomization
X
-
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12 weeks prior to 
randomization;
Week 13-Week 24.
Safety 
Endpoints
∀Safety, including:
&
Type, frequency, and severity of adverse 
events and relationship to luspatercept 
(per NCI CTCAE version 4.0)
Frequency/severity of adverse 
events
X
X
X
All AE Dose 1 Day 
1 through up to 9
weeks post last 
dose. Only related 
AEs from week 9 
until End of Study. 
∀Frequency of antidrug antibodies 
 ADA measurements;
 
 
 
X
X
X
Dose 1 Day 1 
through up to 2 
years 
Secondary 
Efficacy 
Endpoints
∀Proportion of subjects with hematological 
improvement, defined as ≥ 33% reduction 
from baseline in RBC transfusion burden with 
a reduction of at least 2 units from Week 37 to 
Week 48 compared to the 12-week interval 
prior to randomization for luspatercept plus 
BSC versus placebo plus BSC.
Number of RBC units 
transfused from Week 37 to 
Week 48, and in the 12 weeks 
prior to randomization
-
X
-
12 weeks prior to 
randomization; 
Week 37-Week 48
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
37
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Table 2:
Study Endpoints (Continued)
Endpoint
Name
Description
Time of Endpoint Measurement
Timeframe
24 weeks
48 weeks Long -Term 
Secondary 
Efficacy 
Endpoints
∀Proportion of subjects with ≥ 50% reduction 
from baseline in RBC transfusion burden with 
a reduction of at least 2 units from Week 13 to 
Week 24 compared to the 12-week interval 
prior to randomization for luspatercept plus 
BSC versus placebo plus BSC
Number of RBC units 
transfused from Week 13 to 
Week 24, and in the 12 weeks 
prior to randomization
X
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-
12 weeks prior to 
randomization; Week 13-
Week 24
∀Proportion of subjects ≥ 50% reduction from 
baseline in RBC transfusion burden with a 
reduction of at least 2 units from Week 37 to 
Week 48 compared to the 12-week interval 
prior to randomization for luspatercept plus 
BSC versus placebo plus BSC
Number of RBC units 
transfused from Week 37 to 
Week 48, and in the 12 weeks 
prior to randomization
-
X
-
12 weeks prior to 
randomization; Week 37-
Week 48
∀Mean change from baseline in transfusion 
burden (RBC units) from Week 13 to Week 24
Change from baseline as 
continuous variable
X
-
-
12 weeks prior to 
randomization; Week 13-
Week 24
Other 
Efficacy 
Endpoints
∀Mean change from baseline in liver iron 
concentration (LIC, mg/g dw) by MRI 
LIC by MRI
X
X
X
Screening, as per Table 
3, up to last MRI for LIC 
visit 
∀Mean change from baseline in mean daily dose 
of ICT
Daily dose of ICT
X
X
X
12 weeks prior to first IP 
treatment; last 12 weeks 
of the 48-week double-
blind Treatment Period 
or last 12 weeks of study 
treatment if discontinue 
early.
∀Mean change from baseline in serum ferritin
Serum ferritin
X
X
X
4 weeks prior to first IP 
treatment; last 12 weeks 
of the 48 weeks double-
blind Treatment Period 
or last 12 weeks of study 
treatment if discontinue 
early.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
38
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Table 2:
Study Endpoints (Continued)
Endpoint
Name
Description
Time of Endpoint Measurement
Timeframe
24 weeks
48 weeks Long -Term 
Other 
Efficacy 
Endpoints
∀Mean change from baseline in total hip and 
lumbar spine bone mineral density by DXA
Total hip and lumbar spine 
BMD by DXA
X
X
X
Screening up to last 
DXA scan visit
∀Mean change from baseline in myocardial iron 
by MRI
Myocardial iron by T2* MRI
-
X
X
Screening, as per Table 
3, up to last MRI for T2* 
measurement visit.
∀Mean change in Quality of Life measures
Self-reported QoL assessed 
by TranQoL, and SF-36 
questionnaires
X
X
X
Screening, as per Table 
3, up to last QoL 
measurement visit.
∀Healthcare resource utilization
Medical resource utilization 
(refer to Section 9.6.3.7)
X
X
X
Screening until End of 
Study
∀Proportion of subjects who are transfusion 
independent for ≥8 weeks during treatment
RBC transfusions
X
X
X
Dose 1 Day 1 through 3 
weeks post last dose
∀Duration of reduction in transfusion burden 
RBC transfusions (refer to 
Section 9.6.2)
X
X
X
Dose 1 Day 1 until last 
visit date or the date of 
discontinuation
∀Duration of transfusion independence 
RBC transfusions (refer to 
Section 9.6.2)
X
X
X
Dose 1 Day 1 until last 
visit date or the date of 
discontinuation
∀Time to erythroid response 
RBC transfusions (refer to 
Section 9.6.3.9)
X
X
X
Dose 1 Day 1 through 
last visit in the double-
blind Treatment Period 
∀Post-baseline transfusion events frequency 
versus placebo
RBC transfusions 
X
X
X
Dose 1 Day 1 through 3 
weeks post last dose
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
39
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Table 2:
Study Endpoints (Continued)
Endpoint
Name
Description
Time of Endpoint Measurement
Timeframe
24 weeks
48 weeks Long -Term 
Other 
Efficacy 
Endpoints
 
 
 
 
 
Bayesian estimates of subject-
specific PK exposure 
measures (AUC, Cmax, or 
other exposure metrics of 
interest)
 
X
X
X
Dose 1 Day 1 through up 
to unblinding.
ADA = antidrug (ACE-536) antibody; AE = adverse event; AUC = area under the curve, BSC= best supportive care; Cmax = maximum serum concentration; 
dw = dry weight; DXA = dual energy x-ray absorptiometry; 
; HRU = Healthcare resource utilization; ICT = iron chelation therapy; 
IP = investigational product; LIC = liver iron concentration; MRI = magnetic resonance imaging; NCI CTCAE = National Cancer Institute Common 
Terminology for Adverse Events; QoL = quality of life; RBC = red blood cell.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
40
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
3.
OVERALL STUDY DESIGN
3.1.
Study Design
This is a Phase 3, double-blind, randomized, placebo-controlled, multicenter study to determine 
the efficacy and safety of luspatercept (ACE-536) plus BSC versus placebo plus BSC in adults 
who require regular red blood cell transfusion due to !-thalassemia. The study is divided into the 
Screening/Run-in Period, double-blind Treatment Period, double-blind Long-term Treatment 
Period, Open-label Phase and Post-treatment Follow-up Period.  The overall study design is 
described in Figure 4. Further clarifications are listed in the subject management decision tree 
provided in Figure 5.
It is planned to randomize approximately 300 subjects at a 2:1 ratio of luspatercept plus BSC
versus placebo plus BSC.
3.1.1.
Screening/Run-in Period
Upon giving written informed consent, the subject enters the Screening/Run-in Period to 
determine eligibility. Subjects’ identification (ID) number will be allocated via Interactive 
Response Technology (IRT) system as detailed in Section 7.3.  The Screening/Run-in period will 
last at least 12 weeks. During the Screening/Run-in Period, the subject will undergo safety and 
other assessments to determine eligibility for the study as detailed in Table 3, Table of Events.
Subject eligibility will be reviewed with the Sponsor, prior to the subject’s randomization via the 
IRT. Re-screening is allowed and a new subject ID number will be assigned.
The regularly transfused β-thalassemia subjects must have at least 24 weeks of documented 
transfusion history available (including Hb levels prior to each transfusion, the number of units 
transfused, the date of transfusion) prior to randomization.  Twelve weeks of transfusion history 
will be collected prospectively during the Screening/Run-in Period, in addition to the 12 weeks 
historical retrospective data that will be further recorded in the subject’s electronic case report 
form (eCRF).
The 24-week transfusion history prior to randomization into the Treatment Period will be used to 
determine the baseline RBC transfusion burden as well as the mean pre-transfusion Hb value for 
each study subject. 
Subjects will be stratified prior to randomization based on: 
1. Geographical regiona (Viprakasit, 2013):
∀
North America and Europe
∀
Middle East and North Africa
∀
Asia-Pacific
a See Appendix E for list of countries within each region.
3.1.2.
Treatment Period
The subject will enter the Treatment Period once the subject has fulfilled the required
assessments in the Screening Period, has fulfilled the eligibility criteria and has been randomized
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2

EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
41
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
via the IRT system as detailed in Section 7.3. Eligible subjects will be randomized at a ratio of 
2:1 to luspatercept plus BSC or placebo plus BSC treatment at a starting dose level of 1 mg/kg.
The maximum total dose per administration should not exceed 120 mg. After the subject 
randomization via the IRT system the first dose of IP (Dose 1 Day 1) should be administered 
within 3 days of randomization and can be on the same day of randomization, provided that the 
eligibility criteria are met.  If a transfusion occurs on Dose 1 Day 1, the first dose of luspatercept 
should not be given within 1 hour before the start of the transfusion, or 2 hours after the end of 
the transfusion.
Best supportive care will be available to subjects in both the luspatercept and placebo groups. 
This will include RBC transfusions, iron-chelating agents, use of antibiotic therapy, antiviral and 
antifungal therapy, and/or nutritional support as needed, thus minimizing the safety risk to 
subjects. Please refer to Section 8.1.3 for concomitant iron chelation therapy use and Section 
8.1.4 for concomitant RBC transfusions.
The double-blind Treatment Period is considered the first 48 weeks starting from Study Day 1 
(ie, Dose 1 Day 1), independent of dose delays.  Treatment with investigational product for each 
subject begins on Study Day 1. Subjects will begin treatment at a starting dose level of 1 mg/kg
administered by subcutaneous (SC) injection once every 3 weeks for 48 weeks. The starting 
dose with dose modification is detailed in Section 7. Study visits and serial measurements of 
safety and efficacy will be performed as described in Table 3, Table of Events.
The dose level for subjects can be titrated (increased) stepwise up to a maximum of 1.25 mg/kg 
during the Treatment Period as well as during the Long-term Treatment Period and Open-label
Phase unless dose modification is required. Dose titration will be based on erythroid response 
during the previous two dose cycles (~6 weeks).  Dose titration rules are further defined in 
Table 4, and Section 7.2.1.1. Subject’s dose titration should be reviewed with the Sponsor and 
performed in the IRT.
The dose of luspatercept or placebo for each subject can be delayed and/or reduced as per the 
dose modification, dose reduction and dose delay guidelines as detailed in Table 5. Subjects will 
be discontinued from study treatment as appropriate, for reasons listed in Section 11.
The decision to discontinue a subject from study treatment remains the responsibility of the 
treating physician; the Sponsor will not delay or refuse it. However, prior to a decision of 
discontinuing a subject, it is recommended that the Investigator contact the medical monitor and 
forward appropriate supporting documents for review and discussion.
3.1.3.
Long-term Treatment Period
At the investigator’s discretion, subjects completing the 48-week double-blind Treatment Period 
will be able to continue receiving the IP to which they were initially randomized (ie, luspatercept 
or placebo) in a double-blind Long-term Treatment Period for up to 48 weeks after the first dose 
of the last subject or until the date of unblinding.
The double-blind Long-term Treatment Period will continue until all subjects have either 
completed 48 weeks of the double-blind Treatment Period or discontinued before reaching 48 
weeks of the double-blind Treatment Period, or in the event the study is unblinded per Data 
Monitoring Committee (DMC) recommendation. Treatment during the Long-term Treatment 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
42
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Period is subject to dose titration, dose delay and dose reduction, and treatment discontinuation 
as described in Section 7, Table 4 and Table 5.
Subject’s dose titration should be reviewed with the Sponsor and performed in the IVRS.
Dose titration during the Long-term Treatment Period is allowed. Dose titration rules are defined 
as described in Table 4 and Section 7.2.1.1. Please refer to Section 8.1.3 for concomitant iron 
chelation therapy use and Section 8.1.4 for concomitant RBC transfusions.
Subjects will be discontinued from study as appropriate, for reasons listed in Section 11.
Subjects who continue to receive treatment with luspatercept or placebo when the study is 
unblinded (approximately 48 weeks after the first dose of the last subject) may opt to continue 
receiving luspatercept in the Open-label Phase or to discontinue treatment and enter the Post-
treatment Follow-up Period.
3.1.4.
Open-label Phase
Open-label Phase will begin after the study unblinding. The commencement of this Open-label 
Phase will be determined by the enrollment rate and by the availability of primary analysis data 
that justify the use of luspatercept in an Open-label Phase, which will be reviewed by the
independent external DMC. After DMC review of safety and efficacy, DMC will determine if 
the use of luspatercept in subjects previously randomized to receive placebo in this Open-label 
phase is safe and recommended, and if subjects already on luspatercept can continue to be treated
at their current dose level (best supportive care is allowed). In the Open-label Phase, subjects 
may receive luspatercept until all subjects initially assigned to luspatercept in the double-blind 
Treatment Period, complete the total treatment duration of 5 years from subjects’ Dose 1 Day 1 
in the treatment period of this ACE-536-B-THAL-001 study or discontinue early.
Access to the Open-label Phase:
Subjects initially assigned to luspatercept: 
o
should not have discontinued the double-blind phase, in order to be eligible for the Open-
label Phase. 
o
will be in the Open-label Phase until all subjects on luspatercept complete the total 
treatment duration of 5 years from subjects’ Dose 1 Day 1 in the treatment period of this 
ACE-536-B-THAL-001 study or discontinue earlier.
Subjects initially assigned to placebo:
o
can enter the Open-label Phase only if the DMC allows it, as outlined above.
o
can enter the Open-label Phase even if they have discontinued the double-blind phase, but 
were compliant with the protocol 48 weeks post Dose 1 Day 1, and continue their 
participation in the Post-treatment Follow-up Period until the time of unblinding.can stay 
in the Open-label Phase until all subjects initially assigned to luspatercept complete the 
total treatment duration of 5 years from subjects’ Dose 1 Day 1 in the treatment period of 
this ACE-536-B-THAL-001 study or discontinue earlier. 
o
at the time of unblinding, placebo subjects who discontinued treatment and continued 
their participation in the Post-treatment Follow-up Period until the time of unblinding
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
43
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
will have the opportunity to enter the Open-label Phase, if they still fulfill the following 
main eligibility criteria, prior to receiving their first dose of luspatercept: 
∀
Inclusion criteria: numbers 6 and 8 (Refer to Section 4.2); 
∀
Exclusion criteria: numbers “1-10, 15-17 and 21” (Refer to Section 4.3)
Per Investigator’s request, subjects who discontinue luspatercept in the double-blind Treatment 
Period for reasons not related to subject’s safety, and are still in the Post-treatment Follow-up 
Period at the time of unblinding, may access the Open-label Phase and be re-treated with 
luspatercept after consultation with Sponsor Medical Monitor and review of safety and efficacy 
data as long as they still fulfill the above eligibility criteria prior to Dose 1 Day 1.
Note: Subjects who discontinue from the study before the unblinding and without completing the 
PTFP period are not allowed to re-enter this study and access luspatercept in the Open-label 
Phase.
Subjects will be discontinued from study as appropriate, for reasons listed in Section 11.
3.1.5.
Post-treatment Follow-up Period
All subjects who discontinue treatment will undergo a 156-week Post-treatment Follow-up
Period, following the last dose of IP.
All subjects who discontinue treatment after completion of at least 48 weeks of the double-blind 
Treatment Period will enter the Post-treatment Follow-up Period for 156 weeks (ie 3 years). 
Subjects who enter the Long-term Treatment Period or Open-label Phase and discontinue 
treatment during those periods, will also enter the Post-treatment Follow-up Period for 156
weeks.  The Post-treatment Follow-up Period will begin after the last IP dose is received, as per 
the visit schedule laid down in protocol Table 3 (ie, 9-week follow-up, Week 24, and every 24 
weeks after the last dose up to Week 144, follow-up by End of Study visit at Week 156).
Early discontinued subjects, ie, subjects who discontinue before completing 48 weeks in the 
double-blind Treatment Period, will continue to be monitored on Week 9, followed by Week 24, 
Week 48, Week 72, Week 96, Week 120, Week 144 after the last dose up to Week 156
(assessments defined in Table 3, Table of Events).
When the study is unblinded: (i) subjects on luspatercept stay in the Post-treatment Follow-up
Period for up to 156 weeks; (ii) subjects on placebo will stay up to unblinding and will be moved 
to the Open-label Phase after fulfilling appropriate eligibility criteria (refer to Section 3.1.4).
Refer to the subject management decision tree detailed in Figure 5. 
3.1.6.
Committees
The conduct of this study will be overseen by an independent external DMC and by a Steering 
Committee. The DMC will review unblinded data, while the Steering Committee will not have 
access to unblinded data. Refer to Section 9.10.2 and Section 9.10.3 for additional information. 
The study will be conducted in compliance with the International Council on Harmonisation 
(ICH) of Technical Requirements for Registration of Pharmaceuticals for Human Use/Good 
Clinical Practice (GCP) and applicable regulatory requirements.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
44
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Figure 4:
Overall Study Design
BSC = best supportive care; DMC = Data Monitoring Committee; ICF = informed consent form; Q3W = every 3 weeks; SC = subcutaneous; UNBL = unblinding;
LPFD = last patient first dose.
a The historical documentation of transfusion dependence for !-thalassemia subjects (including units transfused and hemoglobin (Hb) levels measured prior to each 
transfusion) for 24 weeks prior to subject randomization, should be available. 
b Dose may be titrated up to a maximum of 1.25 mg/kg.
c Randomization will be 2:1, luspatercept plus BSC versus placebo plus BSC.  
d All subjects, who complete 48 weeks of the double-blind Treatment Period of this study will have the opportunity to continue to a double-blind Long-Term 
Treatment Period at the Investigator’s discretion. Subjects who do not enroll in the double-blind Long-Term Treatment Period or who discontinue early will 
proceed to the Post-treatment Follow-up Period.
e Maximum duration of 48 weeks post LPFD, or when all subjects completed 48 weeks of double-blind treatment or discontinued before reaching 48 weeks double-
blind treatment, or in the event the study is unblinded per DMC recommendation.
f Open-label Phase: Subjects who were compliant with the protocol 48 weeks post Dose 1 Day 1 can enter in the Open-label Phase, unless medically contraindicated 
and as described in Section 3.1.4.
g Early discontinued subjects, ie, subjects who discontinue before completing the double-blind treatment period (48 weeks), will continue to be monitored on week 9, 
followed by 24, 48, 72, 120, 144  after the last dose up to Week 156, ie 3 years (refer to Section 3.1.5).
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
45
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Figure 5:
Subject Management Decision Tree
End of Study Visit
End of Treatment
Subject enters Post-treatment  
FU of 156 weeks. 
Followed by End of Study Visit
Subject enters Open-label Phase. 
Did subject stay on treatment at 
the time of the last planned 
Luspatercept subject completing 
up to 5 years total treatment 
duration from D1D1?
Subject on Luspatercept who 
discontinue DB treatment phase 
do not enter Open-label Phase.* 
Subject Enters Screening For 
Open-label Phase.
Unblinding:
To which treatment arm was the 
patient assigned to during the 
double blind treatment period?
End of Treatment. 
Subject enters Post-treatment  
FU for 156 weeks
Subject continues DB treatment 
in  DB LTTP.
Did Subject remain in DB LTTP 
until UNBL?
Did the Subject Completed 48 
weeks of double blind (DB) 
treatment?
Did the Subject benefits clinically 
from DB treatment
Yes
Unblinding : Subject Enters Open-
label Phase. 
Did subject stay on treatment at 
the time of the last planned 
Luspatercept subject completing 
up to 5 years total treatment 
duration from D1D1?
Yes
Placebo
Luspatercept
No
Yes
No
Yes
Yes
Start here
No
No
No
DB = double-blind; LTTP = Long-term Treatment Period; UNBL = unblinding; D1D1 = Dose 1 Day 1; FU = Follow-up.
*refer also to Section 3.1.4.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
46
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
3.2.
Study Duration for Subjects 
Study participation for each subject includes a Screening/Run-in Period of at least 12 weeks, a 
48-week placebo-controlled double-blind Treatment Period, followed by a double-blind Long-
term Treatment Period and an Open-label Phase. The Post-treatment Follow-up Period will last 
156 weeks (ie 3 years) post last dose.
The study will be comprised of the following periods:
Screening/Run-in Period, will be at least 12 weeks prior to randomization. 
Treatment Period, which will be approximately 48 weeks, independent of Dose Delays
beginning with Dose 1 Day 1.
Long-term Treatment Period, the double-blind Long-term Treatment Period will continue until
all subjects complete 48 weeks of double-blind treatment or discontinue before reaching 48 
weeks of the double-blind Treatment Period, or at the time the study is unblinded (per DMC 
recommendation), whichever occurs first. 
Open-label Phase, the Open-label Phase will continue until all subjects initially assigned to 
luspatercept in the double-blind Treatment Period, complete the total treatment duration of 5 
years from subjects’ Dose 1 Day 1 in the treatment period of this ACE-536-B-THAL-001 study 
or discontinue earlier.
Post-treatment Follow-Up Period, all subjects who discontinue treatment will undergo a 156-
week (ie 3 years) Post-treatment Follow-up Period, following the last dose of IP.  Additional 
information on the visits to complete when subjects discontinue treatment is presented in 
Section 3.1.5.
End of Treatment for each individual subject is defined as the date of the last visit in the 
Treatment Period, the Long-term Treatment Period, or in the Open-label Phase, whichever is the 
later date.
End of Study for each individual subject occurs at the time of completion of the 156-week 
Post-treatment Follow-Up Period or at the time of the end of the Open-label Phase (if subjects 
are still on treatment, see the description above) or at the time of End of Trial as defined below.
3.3.
End of Trial
The End of Trial is defined as when all subjects initially assigned to luspatercept in the double-
blind Treatment Period, reach the maximum treatment duration of 5 years from subjects’ Dose 1 
Day 1 in the treatment period of this ACE-536-B-THAL-001 study or discontinue earlier and 
complete the 156 weeks of the Post-treatment Follow-up Period, whichever occurs later; or the 
date of receipt of the last data point from the last subject that is required for primary, secondary,
 analysis, as pre-specified in the protocol and/or Statistical Analysis Plan
(SAP), whichever is the later date.
The Sponsor may end the trial when all key endpoints and objectives of the study have been 
analyzed, and the availability of a roll-over/extension protocol exists into which any subjects 
who remain on study may be consented and continue to receive access to luspatercept.  Such a 
protocol would be written for a compound that would not yet be commercially available.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
47
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
4.
STUDY POPULATION
4.1.
Number of Subjects 
Approximately 300 subjects diagnosed with transfusion-dependent !-thalassemia (including 
Hemoglobin E/β-thalassemia, excluding Hemoglobin S/β-thalassemia and Hemoglobin H)
requiring regular transfusions will be randomized worldwide.
4.2.
Inclusion Criteria
Subjects must satisfy the following criteria to be enrolled in the study:
1. Male or female, ∋18 years of age at the time of signing the informed consent document 
(ICF).
2. Subject must understand and voluntarily sign an ICF prior to any study-related 
assessments/procedures being conducted.
3. Subject is willing and able to adhere to the study visit schedule (eg, not scheduled to receive 
HSCT) and other protocol requirements.
4. Documented diagnosis of β-thalassemia or Hemoglobin E/β-thalassemia (β-thalassemia with 
mutation and/or multiplication of alpha globin is allowed).
5. Regularly transfused, defined as: 6-20 RBC units* in the 24 weeks prior to randomization and 
no transfusion-free period for > 35 days during that period.
* Sites who prescribe transfusions and have the transfusion records only in volumes should use for conversion of 
volume to units the below criteria, in order to obtain number of units within the last 24 weeks to assess the 
eligibility: 1 unit in this protocol refers to a quantity of packed RBCs approximately 200-350 mL. (i) sites who use 
transfusion bags within this range, or ≥350 mL, the conversion in units should be done by dividing the volume 
transfused to the patient by 350 mL, (ii) sites who use transfusion bags < 200 mL, the conversion in units should 
be done by dividing the volume transfused to the patient by 200 mL.
6. Performance status: Eastern Cooperative Oncology Group (ECOG) score of 0 or 1. 
7. A female of childbearing potential (FCBP) for this study is defined as a female who: 1) has 
achieved menarche at some point, 2) has not undergone a hysterectomy or bilateral 
oophorectomy or 3) has not been naturally postmenopausal (amenorrhea following cancer 
therapy does not rule out childbearing potential) for at least 24 consecutive months (ie, has 
had menses at any time in the preceding 24 consecutive months). FCBP participating in the 
study must:
a.
Have two negative pregnancy tests as verified by the Investigator prior to starting 
study therapy. She must agree to ongoing pregnancy testing during the course of the 
study, and after end of study treatment. This applies even if the subject practices true 
abstinence** from heterosexual contact.
b. Either commit to true abstinence** from heterosexual contact (which must be 
reviewed on a monthly basis and source documented). If a FCBP engages in sexual 
activity that may result in a pregnancy, she must agree to use, and be able to comply 
with, effective*** contraception without interruption, 28 days prior to starting 
investigational product, during the study therapy (including dose interruptions), and 
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b.b.

EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
48
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
for 12 weeks
 after discontinuation of study therapy.
8. Male subjects must:
a.
Practice true abstinence** (which must be reviewed on a monthly basis) or agree to 
use a condom during sexual contact with a pregnant female or a female of 
childbearing potential while participating in the study, during dose interruptions and 
for at least 12 weeks
 
following investigational product 
discontinuation, even if he has undergone a successful vasectomy.
** True abstinence is acceptable when this is in line with the preferred and usual lifestyle of the subject. [Periodic 
abstinence (eg, calendar, ovulation, symptothermal, post-ovulation methods) and withdrawal are not acceptable 
methods of contraception.]
*** Agreement to use highly effective methods of contraception that alone or in combination result in a failure rate 
of a Pearl index of less than 1% per year when used consistently and correctly throughout the course of the study. 
Such methods include: Combined (estrogen and progesterone/progestin containing) hormonal contraception:  Oral; 
Intravaginal; Transdermal; Progestogen/progestin only hormonal contraception associated with inhibition of 
ovulation:  Oral; Injectable hormonal contraception; Implantable hormonal contraception; Placement of an 
intrauterine device (IUD); Placement of an intrauterine hormone-releasing system (IUS); Bilateral tubal occlusion; 
Vasectomized partner; Sexual Abstinence.
4.3.
Exclusion Criteria
The presence of any of the following will exclude a subject from enrollment:
1. Any significant medical condition, laboratory abnormality, or psychiatric illness that 
would prevent the subject from participating in the study.
2. Any condition including the presence of laboratory abnormalities, which places the 
subject at unacceptable risk if he/she were to participate in the study.
3. Any condition that confounds the ability to interpret data from the study.
4. A diagnosis of Hemoglobin S/β-thalassemia or alpha (α)-thalassemia (eg, Hemoglobin 
H).
5. Evidence of active hepatitis C (HCV) infection as demonstrated by a positive HCV-RNA 
test of sufficient sensitivity, or active infectious hepatitis B as demonstrated by the 
presence of HBsAg and/or HBVDNA-positive, or known positive human 
immunodeficiency virus (HIV).
Note: Subjects receiving antiviral therapies should have 2 negative HCVRNA tests 3 months apart.(ie, one test at the 
end of the antiviral therapy and a second test 3 months following the first test).
6. DVT or stroke requiring medical intervention ≤ 24 weeks prior to randomization.
7. Use of chronic anticoagulant therapy is excluded, unless the treatment stopped at least 28 
days prior to randomization. Anticoagulant therapies used for prophylaxis for surgery or 
high risk procedures as well as low-molecular-weight (LMW) heparin for superficial 
venous thrombosis and chronic aspirin are allowed.
8. Platelet count > 1000 x 109/L.
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high
high

EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
49
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
9. Poorly controlled diabetes mellitus within 24 weeks prior to randomization as defined by 
short term (eg, hyperosmolar or ketoacidotic crisis) and/or history of diabetic 
cardiovascular complications (eg, stroke or myocardial infarction).
10. Treatment with another investigational drug or device ≤ 28 days prior to randomization.
11. Prior exposure to sotatercept (ACE-011) or luspatercept (ACE-536).
12. Use of an erythropoiesis-stimulating agent (ESA) ≤24 weeks prior to randomization.
13. Iron chelation therapy, if initiated ≤24 weeks prior to randomization (allowed if initiated 
> 24 weeks before or during treatment).
14. Hydroxyurea treatment ≤24 weeks prior to randomization. 
15. Pregnant or lactating females.
16. Uncontrolled hypertension. Controlled hypertension for this protocol is considered 
≤Grade 1 according to NCI CTCAE version 4.0 (current active minor version).
17. Major organ damage, including:
a.
Liver disease with alanine aminotransferase (ALT) > 3 x the upper limit of 
normal (ULN) or history of evidence of cirrhosis. 
b. Heart disease, heart failure as classified by the New York Heart Association 
(NYHA) classification 3 or higher, or significant arrhythmia requiring treatment, 
or recent myocardial infarction within 6 months of randomization.
c.
Lung disease, including pulmonary fibrosis or pulmonary hypertension which are 
clinically significant ie, ≥Grade 3 NCI CTCAE version 4.0 (current active minor 
version).
d. Creatinine clearance < 60 mL/min (per Cockroft-Gault formula).
18. Proteinuria ≥ Grade 3 according to NCI CTCAE version 4.0 (current active minor 
version).
19. Chronic systemic glucocorticoids ≤12 weeks prior to randomization (physiologic 
replacement therapy for adrenal insufficiency is allowed). Single day glucocorticoid 
treatment (eg, for prevention or treatment of transfusion reactions, is allowed).
20. Major surgery ≤12 weeks prior to randomization (subjects must have completely 
recovered from any previous surgery prior to randomization).
21. History of severe allergic or anaphylactic reactions or hypersensitivity to recombinant 
proteins or excipients in the investigational product (see Investigator Brochure).
22. Cytotoxic agents, immunosuppressants ≤28 days prior to randomization (ie, anti-
thymocite globulin (ATG) or cyclosporine)
23. History of malignancy with the exception of: 
a.
Curatively resected nonmelanoma skin cancer. 
b. Curatively treated cervical carcinoma in situ.
c.
Other solid tumor with no known active disease in the opinion of the investigator.
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23.3. H

EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
50
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
5.
TABLE OF EVENTS
Table 3:
Table of Events
Assessments
Section
Screening/
Run-in 
Period
  Week -12 
to 
Day -1
Treatment Period (double-blinded)
Long-term 
Treatment 
Period13
(double-
blinded)
every 3-wk 
visits from 
Week 49 (ie,
Dose 17 if no 
dose delays) 
/Day 1 
(± 5 days)
Open-label Phase,
every 3-wk visits 
from unblinding
(± 5 days)
Day 22 
Post 
Last Dose 
/ 
Treatment 
D/C7
Post-treatment Follow-up Period 
(± 7 days)
Luspatercept/
placebo
Dose 1 
Schedule
(+ 7 days)
Luspatercept/placebo
Doses 2 up to max 48 
weeks Treatment 
(± 3 days)
Follow-
up 
Week 9
(from 
last 
dose) 23
Only if 14
Early 
Discont. –
Follow-up
Visits
weeks  24, 
48, 72, 96, 
120, 144
(from last 
dose)23
All 
subjects
: 
Follow-
Up
Visits
weeks
24, 48, 
72, 96, 
120, 144
(from 
last 
dose)23
End of 
Study1
5/
Follow
-up 
week 
156 
(from 
last 
dose)2
3
Day
1
Day
1
Day
8
Day
15
Dose 1 
for 
Placebo, 
Discont.18
Dose 
X 
Day 
119
Study Entry and General Assessments
Informed Consent
6.1
X
-
-
-
-
-
-
-
-
-
-
-
-
Inclusion/Exclusion 
Criteria
6.1
X
-
-
-
-
-
X
-
-
-
-
-
-
Demographics
6.1
X
-
-
-
-
-
-
-
-
-
-
-
-
Medical History
6.1
X
-
-
-
-
-
-
-
-
-
-
-
-
β-thalassemia genotype 
(ie, beta and alpha globin 
mutations, only if not 
available in subject
medical history)20
6.1
X
-
-
-
-
-
-
-
-
-
-
-
-
Hepatitis B & C 16
6.1
X
-
-
-
-
-
-
-
-
-
-
-
-
Iron Chelation Therapy
6.1 to 
6.6
X
Record on ongoing basis, until 9 weeks Post-last Dose24
Other Prior / 
Concomitant / Post 
(disease specific) 
Medications / Therapies
6.1 to 
6.6
X
Record on ongoing basis, until 9 weeks Post-last Dose24
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
51
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Table 3:
Table of Events (Continued)
Assessments
Section
Screening/
Run-in 
Period
  Week -12 
to 
Day -1
Treatment Period (double-blinded)
Long-term 
Treatment 
Period13
(double-
blinded)
every 3-wk 
visits from 
Week 49 (ie,
Dose 17 if no 
dose delays) 
/Day 1 
(± 5 days)
Open-label Phase,
every 3-wk visits 
from unblinding
(± 5 days)
Day 22 
Post 
Last Dose / 
Treatment 
D/C7
Post-treatment Follow-up Period 
(± 7 days)
Luspatercept/
placebo
Dose 1 
Schedule
(+7 days)
Luspatercept/placebo
Doses 2 up to max 48 
weeks Treatment 
(± 3 days)
Follow-
up 
Week 9 
(from 
last 
dose) 23
Only if 14
Early 
Discont. –
Follow-up 
Visits weeks  
24, 48, 72, 
96, 120, 144
(from last 
dose)23
All 
subjects: 
Follow-
Up 
Visits 
weeks   
24, 48, 
72, 96, 
120, 144
(from 
last 
dose)23
End of 
Study15
/ 
Follow-
up 
week 
156 
(from 
last 
dose)23
Day
1
Day
1
Day
8
Day
15
Dose 1 
for 
Placebo, 
Discont.18
Dose 
X Day 
119
Prior/concomitant/post 
procedures (eg, surgery, 
radiation therapy)
6.1 to 
6.6
X
Record on ongoing basis, until 9 weeks Post-last Dose24
Transfusion Assessment 
(≥ 24 weeks of history 
prior to Dose 1 Day 1)
6.1 to 
6.6
X
Record on ongoing basis, until 9 weeks Post-last Dose24
Subject Transfusion –
information collection25
6.1 to 
6.6
X
Record on ongoing basis, until 9 weeks Post-last Dose24
Safety Assessments
Adverse Events
6.1 to 
6.7
Continuous starting after informed consent signature, until 9 weeks post last dose, related AE to be reported until End of Study
Malignancy and Pre-
malignancy Reporting
(Section 10.5.2)26
6.1 to 
6.7
Continuous starting after informed consent signature, regardless of causality reporting occurrence of any case
X26
X26
X26
Vital Signs1
6.1 to 
6.7
X (within 
4 wks 
prior Dose 
1 Day 1)
X
X
-
-
X
X
X
X
X
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1( 3

EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
52
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Table 3:
Table of Events (Continued)
Assessments
Section
Screening/
Run-in 
Period
  Week -12 
to 
Day -1
Treatment Period (double-blinded)
Long-term 
Treatment 
Period13
(double-
blinded)
every 3-wk 
visits from 
Week 49 (ie,
Dose 17 if no 
dose delays) 
/Day 1 
(± 5 days)
Open-label Phase,
every 3-wk visits 
from unblinding
(± 5 days)
Day 22 
Post 
Last Dose / 
Treatment 
D/C7
Post-treatment Follow-up Period 
(± 7 days)
Luspatercept/
placebo
Dose 1 
Schedule
(+7 days)
Luspatercept/placebo
Doses 2 up to max 48 
weeks Treatment 
(± 3 days)
Follow-
up 
Week 9
(from 
last 
dose) 23
Only if 14
Early 
Discont. –
Follow-up 
Visits weeks  
24, 48, 72, 
96, 120, 144
(from last 
dose)23
All 
subjects: 
Follow-
Up 
Visits 
weeks   
24, 48, 
72, 96, 
120, 144
(from 
last 
dose)23
End of 
Study15
/ 
Follow-
up 
week 
156 
(from 
last 
dose)23
Day
1
Day
1
Day
8
Day
15
Dose 1 
for 
Placebo, 
Discont.18
Dose 
X Day 
119
Height (at Screening 
only)/Weight
6.1 to 
6.7
X (within 
4 wks 
prior Dose 
1 Day 1)
X
X
-
-
X
X
X
X
X
ECOG Performance 
Status
6.1 and 
6.4
X (within 
4 wks 
prior Dose 
1 Day 1)
X
-
-
-
-
X
-
-
-
-
-
-
12-Lead 
Electrocardiogram (ECG) 
– read locally
6.1, 
6.2, 
6.4, 
and 6.5
X (within 
4 wks 
prior Dose 
1 Day 1)
-
-
X 
(Dose 6 
only)
-
-
X
-
X
-
-
-
-
Cardiac Doppler 
Echocardiography, 
MUGA or MRI17; 21: 
LVEF 
6.1, 
6.2, 6.3
X
-
X (wk 
24, wk 
48  
only)-
-
-
X (wk 96 only) 
9
-
-
-
-
-
-
-
Pregnancy Testing2
6.1 to 
6.6
X (within 
4 wks 
prior Dose 
1 Day 1; 
serum 
only)
X
X
-
-
X
X
X
X
X
-
-
-
Menstrual status (female 
only)
6.1 to 
6.6
X
X
X
-
-
X
X
X
X
X
-
-
-
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Dose 
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X Day 
X Day 
119
19
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
53
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Table 3:
Table of Events (Continued)
Assessments
Section
Screening/
Run-in 
Period
  Week -12 
to 
Day -1
Treatment Period (double-blinded)
Long-term 
Treatment 
Period13
(double-
blinded)
every 3-wk 
visits from 
Week 49 (ie,
Dose 17 if no 
dose delays) 
/Day 1 
(± 5 days)
Open-label Phase,
every 3-wk visits 
from unblinding
(± 5 days)
Day 22 
Post 
Last Dose / 
Treatment 
D/C7
Post-treatment Follow-up Period 
(± 7 days)
Luspatercept/
placebo
Dose 1 
Schedule
(+7 days)
Luspatercept/placebo
Doses 2 up to max 48 
weeks Treatment 
(± 3 days)
Follow-
up 
Week 9
(from 
last 
dose) 23
Only if 14
Early 
Discont. –
Follow-up 
Visits weeks  
24, 48, 72, 
96, 120, 144
(from last 
dose)23
All 
subjects: 
Follow-
Up 
Visits 
weeks  
24, 48, 
72, 96, 
120, 144
(from 
last 
dose)23
End of 
Study15
/ 
Follow-
up 
week 
156 
(from 
last 
dose)23
Day
1
Day
1
Day
8
Day
15
Dose 1 
for 
Placebo, 
Discont.18
Dose 
X Day 
119
Hematology3 (central lab; 
use local lab for predose 
hemoglobin, in case of 
AE, or between doses; 
reticulocytes and 
erythroblast to be 
measured by local lab; in 
Open-label Phase – use 
local labs)
6.1 to 
6.6
X (within 
4 wks 
prior Dose 
1 Day 1)
X
X
X 
(Dose 6 
only)
X 
(Dose 
6 only)
X11
X
X
X
X
-
-
-
Serum Chemistry4
(predose: central lab; use 
local lab in case of AE, 
or between doses; in 
Open-label Phase – use 
local labs)
6.1 to 
6.6
X (within 
4 wks 
prior Dose 
1 Day 1)
X
X
-
-
X11 (every 4 
doses)
X
-
X
X
-
-
-
Urinalysis: 
microalbumin, 
creatinine, 
microalbumin/creatinine 
ratio (morning void; 
central lab; in Open-
label Phase – use local 
labs)
6.1.1 to 
6.6
X (within 
4 wks 
prior Dose 
1 Day 1)
-
X (every 
4 doses)
-
-
X11 (every 4 
doses)
X
-
X
X
-
-
-
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Dose 
Dose 
X Day 
X Day 
119
19
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
54
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Table 3:
Table of Events (Continued)
Assessments
Section
Screening/
Run-in 
Period
  Week -12 
to 
Day -1
Treatment Period (double-blinded)
Long-term 
Treatment 
Period13
(double-
blinded)
every 3-wk 
visits from 
Week 49 (ie,
Dose 17 if no 
dose delays) 
/Day 1 
(± 5 days)
Open-label Phase,
every 3-wk visits 
from unblinding
(± 5 days)
Day 22 
Post 
Last Dose / 
Treatment 
D/C7
Post-treatment Follow-up Period 
(± 7 days)
Luspatercept/
placebo
Dose 1 
Schedule
(+7 days)
Luspatercept/placebo
Doses 2 up to max 48 
weeks Treatment 
(± 3 days)
Follow-
up 
Week 9
(from 
last 
dose) 23
Only if 14
Early 
Discont. –
Follow-up 
Visits weeks  
24, 48, 72, 
96, 120, 144 
(from last 
dose)23
All 
subjects: 
Follow-
Up 
Visits 
weeks   
24, 48, 
72, 96, 
120, 144 
(from 
last 
dose)23
End of 
Study15
/ 
Follow-
up 
week 
156 
(from 
last 
dose)23
Day
1
Day
1
Day
8
Day
15
Dose 1 
for 
Placebo, 
Discont.18
Dose 
X Day 
119
Serum Erythropoietin 
(predose; central lab)
6.1.1 to 
6.5
-
X
X
(every 4 
doses)
-
-
-
-
-
X
-
-
-
-
Serum PK (predose if on 
dosing day; central lab)10
6.8
-
X
X
(Dose 2, 
3, 4, 5 
and 6, 8, 
10, 12, 
14, 16)
X 
(Dose 6 
only)
X 
(Dose 
6 only)
X (every 6 
doses, eg, at 
Dose 22, 28, 
34….)
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
55
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Table 3:
Table of Events (Continued)
Assessments
Section
Screening/
Run-in 
Period
  Week -12 
to 
Day -1
Treatment Period (double-blinded)
Long-term 
Treatment 
Period13
(double-
blinded)
every 3-wk 
visits from 
Week 49 (ie,
Dose 17 if no 
dose delays) 
/Day 1 
(± 5 days)
Open-label Phase,
every 3-wk visits 
from unblinding
(± 5 days)
Day 22 
Post 
Last Dose / 
Treatment 
D/C7
Post-treatment Follow-up Period 
(± 7 days)
Luspatercept/
placebo
Dose 1 
Schedule
(+7 days)
Luspatercept/placebo
Doses 2 up to max 48 
weeks Treatment 
(± 3 days)
Follow-
up 
Week 9
(from 
last 
dose) 23
Only if 14
Early 
Discont. –
Follow-up 
Visits weeks  
24, 48, 72, 
96, 120, 144 
(from last 
dose)23
All 
subjects: 
Follow-
Up 
Visits 
weeks   
24, 48, 
72, 96, 
120, 144 
(from 
last 
dose)23
End of 
Study15
/ 
Follow-
up 
week 
156 
(from 
last 
dose)23
Day
1
Day
1
Day
8
Day
15
Dose 1 
for 
Placebo, 
Discont.18
Dose 
X Day 
119
Antidrug antibody 
(ADA)5, 10
(central lab)
6.9
-
X
X (Dose 
2, 4 and 
6; 8, 12, 
16)
-
-
X (every 6 
doses, eg, at 
Dose 22, 28, 
34….)10
X (only if 
positive at 
unblindin
g, every 6 
doses up 
to 2 years 
of the 
Dose 1
Day 1 of 
the 
DBTP)
X 
(only 
if
positiv
e at 
unblin
ding, 
every 
6 
doses 
up to 2 
years 
of 
Dose
1 Day
1 of 
the 
DBTP
)10
-
X
X (every 24
wks as 
applicable)10
X (every 
24 wks 
as 
applicab
le)10
-
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
56
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Table 3:
Table of Events (Continued)
Assessments
Section
Screening/
Run-in 
Period
  Week -12 
to 
Day -1
Treatment Period (double-blinded)
Long-term 
Treatment 
Period13
(double-
blinded)
every 3-wk 
visits from 
Week 49 (ie,
Dose 17 if no 
dose delays) 
/Day 1 
(± 5 days)
Open-label Phase,
every 3-wk visits 
from unblinding
(± 5 days)
Day 22 
Post 
Last Dose 
/ 
Treatment 
D/C7
Post-treatment Follow-up Period 
(± 7 days)
Luspatercept/
placebo
Dose 1 
Schedule
(+7 days)
Luspatercept/placebo
Doses 2 up to max 48 
weeks Treatment 
(± 3 days)
Follow-
up 
Week 9
(from 
last 
dose) 23
Only if 14
Early 
Discont. –
Follow-up 
Visits 
weeks  24, 
48, 72, 96, 
120, 144
(from last 
dose)23
All 
subjects: 
Follow-
Up Visits 
weeks   
24, 48, 
72, 96, 
120, 144
(from 
last 
dose)23
End of 
Study1
5/ 
Follow
-up 
week 
156 
(from 
last 
dose)2
3
Day
1
Day
1
Day
8
Day
15
Dose 1 
for 
Placebo, 
Discont.18
Dose 
X 
Day 
119
Efficacy and Other Assessments
MRI for LIC (with T2* 
or R2, mg/g dw) 12, 17
6.1, 
6.1.1,
6.2,
6.3, 
6.4, 
6.5
X
-
X (wk 
24 & wk 
48)
-
-
wk 96 only, if 
applicable9
-
wk 96 
only, 
if 
applic
able9
X (if not 
performed 
within the 
last 12 
wks)
-
X (wk 48) 
post Dose 
1) 
-
-
MRI or abdominal 
ultrasound for spleen 
measurements for 
spleen, unless 
splenectomized12,17
6.1, 
6.1.1, 
6.2,
6.3, 
6.4, 
6.5
X
-
X (wk 
24 & wk 
48)
-
-
wk 96 only, if 
applicable9
-
wk 96 
only, 
if 
applic
able9
X (if not 
performed 
within the 
last 12 
wks)
-
X (wk 48)
post Dose 
1)
-
-
MRI for myocardial iron 
(T2*; ms) 12,17
6.1, 
6.1.1,
6.2, 
6.3, 
6.5
X
-
X (wk 
48)
-
-
wk 96 only, if 
applicable 9
-
wk 96 
only, 
if 
applic
able9
X (if not 
performed 
within the 
last 12 
wks)
-
X (wk 48) 
post Dose 
1) 
-
-
DXA scan6,17– total hip, 
lumbar spine (read 
locally)
6.1, 
6.1.1, 
6.2,
6.3,
6.4, 
6.5
X
-
X (wk 
48)
-
-
wk 96 only, if 
applicable 9
-
wk 96 
only, 
if 
applic
able9
X(if not 
performed 
within the 
last 24
wks)
-
X (wk 48) 
post Dose 
1) 
-
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
57
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Table 3:
Table of Events (Continued)
Assessments
Section
Screening/
Run-in 
Period
  Week -12 
to 
Day -1
Treatment Period (double-blinded)
Long-term 
Treatment 
Period13
(double-
blinded)
every 3-wk 
visits from 
Week 49 (ie,
Dose 17 if no 
dose delays) 
/Day 1 
(± 5 days)
Open-label Phase,
every 3-wk visits 
from unblinding
(± 5 days)
Day 22 
Post 
Last Dose / 
Treatment 
D/C7
Post-treatment Follow-up Period 
(± 7 days)
Luspatercept/
placebo
Dose 1 
Schedule
(+7 days)
Luspatercept/placebo
Doses 2 up to max 48 
weeks Treatment 
(± 3 days)
Follow-
up 
Week 9
(from 
last 
dose) 23
Only if 14
Early 
Discont. –
Follow-up 
Visits weeks  
24, 48, 72, 
96, 120, 144
(from last 
dose)23
All 
subjects: 
Follow-
Up 
Visits 
weeks   
24, 48, 
72, 96, 
120, 144
(from 
last 
dose)23
End of 
Study15
/ 
Follow-
up 
week 
156
(from 
last 
dose)23
Day
1
Day
1
Day
8
Day
15
Dose 1 
for 
Placebo, 
Discont.18
Dose 
X Day 
119
QoL Questionnaire 
(TranQol, SF36), 
assessments to be 
performed independent 
of Dose Delays
6.1, 
6.1.1, 
6.2, 
6.3, 
6.11
X (within 
4 wks 
prior Dose 
1 Day 1)
-
X (wk 
12, 24, 
36 &  
wk 48)
-
-
every 12 weeks
-
-
-
-
-
-
-
Healthcare Resource 
Utilization
6.1 to 
6.6
Record on ongoing basis, until 9 weeks Post-last Dose24
Serum Ferritin (predose, 
central lab; screening 
value at least 12 weeks 
prior to randomization;
in Open-label Phase –
use local labs)
6.1 to 
6.6
X (within 
4 wks 
prior Dose 
1 Day 1)
X
X
-
-
X11 (every 4 
doses)
X
-
X
X
-
-
-
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
58
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Table 3:
Table of Events (Continued)
Assessments
Section
Screening/
Run-in 
Period
  Week -12 
to 
Day -1
Treatment Period (double-blinded)
Long-term 
Treatment 
Period13
(double-
blinded)
every 3-wk 
visits from 
Week 49 (ie,
Dose 17 if no 
dose delays) 
/Day 1 
(± 5 days)
Open-label Phase,
every 3-wk visits 
from unblinding
(± 5 days)
Day 22 
Post 
Last Dose / 
Treatment 
D/C7
Post-treatment Follow-up Period 
(± 7 days)
Luspatercept/
placebo
Dose 1 
Schedule
(+7 days)
Luspatercept/placebo
Doses 2 up to max 48 
weeks Treatment 
(± 3 days)
Follow-
up 
Week 9 
(from 
last 
dose) 23
Only if 14
Early 
Discont. –
Follow-up 
Visits weeks  
24, 48, 72, 
96, 120, 144 
(from last 
dose)23
All 
subjects: 
Follow-
Up 
Visits 
weeks   
24, 48, 
72, 96, 
120, 144 
(from 
last 
dose)23
End of 
Study15
/ 
Follow-
up 
week 
156 
(from 
last 
dose)23
Day
1
Day
1
Day
8
Day
15
Dose 1 
for 
Placebo, 
Discont.18
Dose 
X Day 
119
Investigational Product (IP)
Administer Luspatercept / 
Placebo
Perform Drug 
Accountability8
6.1.1
-
X
X
-
-
X
X
X
-
-
-
-
-
ADA = antidrug (ACE-536) antibody; AE = adverse event; ALT = alanine aminotransferase; ANC = absolute neutrophil count; AST = aspartate aminotransferase; BUN = blood 
urea nitrogen; eCRF = electronic case report form; D/C = discontinuation; DBP = diastolic blood pressure; DBTP = double-blind Treatment period; DXA = dual energy x-ray 
absorptiometry; ECOG = Eastern Cooperative Oncology Group; Early Discont. = early discontinued from treatment subjects;
; IP= 
investigational product; Hct = hematocrit; Hb = hemoglobin; HIV = human immunodeficiency virus; ICF = informed consent form; lab = laboratory assessments; LDH = lactic 
dehydrogenase; LIC= liver iron concentration; LTTP = Long-term Treatment Period; LVEF = left ventricular ejection fraction; MCH = mean corpuscular hemoglobin; MCHC = 
mean corpuscular hemoglobin concentration; MCV = mean corpuscular volume; MRI = magnetic resonance imaging; MUGA = Multi  Gated Acquisition Scan; 
PK = Pharmacokinetic; QoL = quality of life; RBC = red blood cell; RDW = red blood cell distribution width; SAEs = serious adverse events; SBP = systolic blood pressure; SF 
= Short Form; SGOT = serum glutamic oxaloacetic transaminase; SGPT = serum glutamic pyruvic transaminase; ToE = Table of Events; WBC = white blood cell.; wk = week; 
wks = weeks.
1 Vital signs (including heart rate, seated blood pressure [DBP and SBP], and temperature) will be measured at Screening, on Days 1 of each dose prior to administration of IP, at 
Treatment Discontinuation, at each visit during post-treatment Follow-Up, and at End of Study. Seated blood pressure should be confirmed by two separate measurements 
obtained predose and 10 minutes apart.  The Investigator should report any clinically significant abnormal findings as adverse events.
2 Pregnancy test is required for all female subjects of childbearing potential.  Serum beta human chorionic gonadotropin (β-hCG pregnancy test (which must be negative) with a 
minimum sensitivity of 25 mIU/mL will be performed within 4 weeks prior Dose 1 Day 1. Urine (or serum) pregnancy test will be performed to assess subject eligibility within 
72 hours prior to the first administration of IP, if the initial serum pregnancy test did not already occur with 72 hours of dosing (negative results required for IP administration). 
During the Treatment period urine or serum pregnancy test is allowed.  
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
59
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
3 Hematology assessment includes RBC count, Hb, Hct, MCV, MCH, MCHC, RDW, WBC count with differential, absolute neutrophil count (ANC) and absolute lymphocytes, 
platelet and reticulocyte absolute values, and circulating erythroblast (nucleated RBC) counts.  On dosing days, hemoglobin levels should be measured prior to dosing with IP to 
ensure Hb levels are within the acceptable ranges to allow luspatercept administration as per Section 7.2 and that luspatercept dose modification rules are followed as outlined in
Table 5.  Laboratory evaluations may be repeated more frequently if clinically indicated.  
4 Serum chemistry (calcium, magnesium, phosphorus, blood urea nitrogen [BUN], creatinine, creatinine clearance, albumin, total protein, alkaline phosphatase, bilirubin [total, 
non-conjugated], AST/SGOT, ALT/SGPT, LDH and uric acid).  If clinically significant, any or all laboratory evaluations should be reported as AEs and repeated more 
frequently, if clinically indicated. 
5 For ADA test, additional blood draws are not needed.  The test will be performed using the serum collected for PK samples. If ADA test is positive at the time of End of Study, 
the subject may need to return for additional ADA testing.
6 DXA scan of the lumbar spine and total hip for bone mineral density (BMD).
7 Day 22 post-last dose corresponds to the end of Treatment Period.  
8 Calculated doses requiring reconstituted volume greater than 1 mL should be divided equally into two syringes and injected into two separate sites – same anatomical location 
but opposite side of the body (example left thigh and right thigh). In case of 2 simultaneous injections, the injection sites must be different. In case of dose delays refer to Section 
6.2.1 and Section 6.3.1. Only for Dose 1 Day 1, IP administration should be at the end of the Screening/Run-in period, which is at least 12 weeks.
9 Assessments to be performed if the subject is in this study at Week 96, not applicable if subject does not enter into the LTTP.
10During the Long-term Treatment Period, PK and ADA samples will be collected every 6 doses. The maximum ADA monitoring period will be two years from dose 1 day 1 of 
the double-blind Treatment Period. During the Open-label Phase: for placebo-cross-over subjects, if positive at unblinding, continue every 6 doses up to 2 years from Dose 1 
Day 1 of the double-blind Treatment Period; for subjects continuing treatment with luspatercept, only if positive at unblinding, every 6 doses up to 2 years from Dose 1 Day 1
of the double blinded treatment period.. During the Post-Treatment Follow-Up : Before unblinding, ADA monitoring, every 24 weeks (post last dose), at post-treatment follow-
up visits will continue for up to two years from Dose 1 Day 1 of the double-blind Treatment Period.  After unblinding, ADA monitoring, every 24 weeks (post last dose), at all 
post-treatment follow-up visits will continue only if subjects’ last available ADA is positive and have not reached the 2-year maximum limit for ADA monitoring.  .  ADA/PK 
sampling per Investigator’s or Sponsor’s discretion is allowed and should be recorded as unscheduled visit.
11During the Long-term Treatment Period these parameters should be measured by Central Lab. Data to be entered in the eCRF.
12MRI for LIC, myocardial iron (T2*) and for spleen volume can be performed on one MRI acquisition if possible.
13LTTP will end when all subjects completed 48 weeks of double-blind treatment or discontinue before reaching 48 weeks double-blind treatment, whichever is the earlier date, or 
at the time the study is unblinded (per DMC recommendation). Only subjects that do not discontinue for reasons as described in Section 11 can enter in the LTTP.
14Only for subject who discontinue prior to completion of 48 weeks in the double-blind Treatment Period.
15End of Study visit can occur at any time up to at least 156 weeks post last dose. 
16   HCV-RNA test and HBsAg and/or HBVDNA .
17+/- 10 day window around for MRI assessments and DXA is allowed (MRI for LIC, myocardiac iron, spleen and LVEF). These assessments to be performed as indicated on 
specified week, regardless of dose delays. MRIs and DXA scans performed within the 4 weeks prior to the ICF signature can be accepted, if subject does not show any relevant 
clinical symptoms judged by the Investigator as sufficient reason to repeat these procedures within the Screening/Run-in period and agreed with the Sponsor.
18Placebosubject who discontinued the study, but were compliant with the protocol 48 weeks post Dose 1 Day 1, and continued their participation in the Post-treatment Follow-up 
Period until the time of unblinding, refer to Section 3.1.4.
19For all subjects on treatment at the time of Open-label Phase initiation, continue with the appropriate dose number.
20For subjects who have documented diagnosis of β-thalassemia in their medical history, by other methodology or do not have a source laboratory report in the medical files, the β-
thalassemia genotype can be done at any time during the course of the study.  
21 The same Cardiac Doppler Echocardiography technique should be used within a subject throughout the study duration.
22As per standard of care.
23Follow-up visits at Weeks 9, 24, 48, 72, 96, 120, 144 and 156 post last dose should be performed by all subjects, regardless if a subject has Early Discontinued or not.
24For early discontinuation subjects, these parameters to be reported up to 48 weeks Post Dose 1 Day 1 or Week 9 post last dose whichever is the later date.
25In the event the subject receives transfusions at outside institutions during the course of study participation, a subject diary will be available for the subject, in order to capture 
any transfusions occurring outside the investigational site when there is not an established plan in place.
26 Subjects are required to see the Investigator at least every 24 weeks to assess for the presence of malignancy and pre-malignancy, as per standard of care.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
60
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
6.
PROCEDURES
Any questions regarding the protocol should be directed to the Celgene Medical Monitor or 
designee. 
All of the protocol required assessments are listed in Section 5, Table 3 with an “X” indicating at 
which visits the assessments are to be performed.  All data obtained from these assessments must 
be recorded in the subject’s source documentation.  All visits during the Treatment Period must 
occur within ± 3 days of the scheduled day.  An administrative visit window of ± 5 days is 
permitted in the Long-term Treatment Period, as well as Open-label Phase. During the Post-
treatment Follow-Up Period, visits must occur within ± 7 days of the scheduled day.  Procedures 
are described in detail below.
Subjects must have Hb assessed and results available prior to each study drug administration. If a 
transfusion occurs prior to dosing, the pre-transfusion Hb should be considered for dosing 
purposes (ie, Hb ≥ 14 days post- transfusion).
Subjects must have blood pressure assessed prior to each study drug administration.  Blood 
pressure values should be confirmed by means of two readings obtained approximately 10
minutes apart with the subject seated for approximately 10 minutes prior to initial reading. The 
two readings should be recorded in the source data file.
Safety laboratory analyses and all laboratory assessments will be performed centrally (except as 
otherwise indicated in Table 3) during the double-blind Treatment Period and Long-term 
Treatment Period (except otherwise stated in Table 3).  Blood or urine samples for local 
laboratory assessments are allowed in the following circumstances when timely results are 
needed: eg, randomization, study treatment dosing decisions, assessments between clinic visits, 
or adverse event.  Local laboratory data should be collected in the eCRF if relevant to dose 
administration, modification and AE, or when no central laboratory results were obtained.
During the Open-label Phase all laboratory assessments will be performed locally. 
6.1.
Screening/Run-in Period
Screening/run-in evaluations will be performed for all subjects to determine study eligibility. 
These evaluations must be completed within 12 weeks of randomization (refer to Table of 
Events, Table 3 for further information). 
Waivers to the protocol will not be granted during the conduct of this trial, under any 
circumstances.
Screening laboratory values must demonstrate subject eligibility, but may be repeated within the 
screening window, if necessary, or subject can be re-screened (refer to Section 6.1.1 for further 
information on re-screening).
The regularly transfused β-thalassemia subjects must have at least 24 weeks of documented 
transfusion history available (including Hb levels prior to each transfusion, the number of units 
transfused, the dates of transfusion) prior to randomization.  The 12 weeks of transfusion history 
will be collected prospectively during the Screening/Run-in Period, and the 12 weeks historical 
retrospective data will be further recorded in the subject’s electronic case report form (eCRF).
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
61
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
The following will be performed at screening/run-in as specified in the Table of Events (Table 
3), after informed consent has been obtained:
∀
Written dated informed consent
∀
Assessment of inclusion/exclusion criteria for study eligibility
∀
Demographics (date of birth, sex, race, and ethnicity-if allowed by local regulations)
∀
Complete medical history: specific information regarding all relevant medical 
conditions diagnosed (occurring prior to screening) should be recorded including the
staging, histology, and any additional details, as needed. Prior ESA history (24 weeks
prior to randomization) should also be recorded.
∀
β-thalassemia genotype (ie, beta and alpha globin mutations, only if not available in 
subject medical history)
∀
Hepatitis B & C;
∀
Iron chelating therapies, including type of iron chelating therapy, period of receive 
(ie, dates) and dose changes: at least 12 weeks of history before randomization 
∀
Other prior medications/therapies: including those taken ≤ 28 days before 
screening/run-in, such as surgery, radiation, systemic or any other therapy for the 
subject’s disease
∀
Prior procedures (including all procedures occurring ≤ 28 days before screening/run-
in)
∀
Transfusion assessment - RBC transfusion history (≥ 24 weeks of history prior to 
Dose 1 Day 1, ie, 12 weeks of transfusion history will be collected prospectively 
during the Screening/Run-in Period, and 12 weeks transfusion history will be 
collected retrospectively), including Hb levels prior to each transfusion, the number 
of units transfused, the dates of transfusion. If available, the volume transfused in mL
at each transfusion and hematocrit (Hct) of the transfused unit should be collected, as 
well as the age when subject started regular transfusion. If available, additional 
transfusion history up to 1 year transfusion history can be collected in the eCRF.
o
In the event the subject receives transfusions at outside institutions during the 
course of study participation, a subject diary will be available for the subject,
in order to capture any transfusions occurring outside the investigational site 
when there is not an established plan in place.
∀
Adverse event assessment regardless of causality begins when the subject signs the 
informed consent form, until 9 weeks post last dose. Only, related AE will be
collected from 9 weeks until End of Study. 
∀
Malignancy and Pre-Malignancy Reporting:
o
Continuous starting after informed consent signature, regardless of causality 
reporting occurrence of any case.
o
The occurrence of a new malignancy or pre-malignant lesion will be 
monitored and collected as an event of interest and should be included as part 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
62
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
of the assessment of adverse events throughout the course of the study. 
Investigators are to report the development of any new malignancy or pre-
malignant lesion as a serious adverse event, regardless of causal relationship 
to IP (study drug[s] or control), occurring at any time for the duration of the 
study, from the time of signing the ICF up to and including 156 weeks of 
follow-up (refer to Section 10.5.2 for additional information).
∀
Vital signs (including seated blood pressure, temperature, and heart rate). Seated 
blood pressure should be confirmed by two separate measurements obtained 10
minutes apart - assessment should be performed within 4 weeks prior to Dose 1 Day 1
∀
Height, weight - assessment should be performed within 4 weeks prior to Dose 1 Day 
1
∀
Eastern Cooperative Oncology Group (ECOG) performance status (Appendix B) -
assessment should be performed within 4 weeks prior to Dose 1 Day 1
∀
12-lead electrocardiogram (ECG) - assessment should be performed within 4 weeks 
prior to Dose 1 Day 1 (read locally)
∀
Cardiac Doppler echocardiography, MUGA or MRI - left ventricular ejection 
fraction (LVEF)
∀
Pregnancy testing is required for all female subjects of childbearing potential.  Serum 
beta human chorionic gonadotropin (β-hCG pregnancy test (which must be negative) 
with a minimum sensitivity of 25 mIU/mL will be performed within 4 weeks prior 
Dose 1 Day 1.
∀
For female subjects– menstrual status
∀
Hematology assessment includes a RBC count, Hb, Hct, mean corpuscular volume 
(MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin 
concentration (MCHC), red blood cell distribution width (RDW), white blood cell 
(WBC) count with differential, absolute neutrophil count (ANC), absolute 
lymphocytes, platelets, - central laboratory assessment should be performed within 4 
weeks prior to Dose 1 Day 1. Absolute reticulocytes, and circulating erythroblasts
(nucleated RBC) counts should be measured by local laboratory assessment within 4 
weeks prior to Dose 1 Day 1 
∀
Serum chemistry includes calcium, magnesium, phosphorus, blood urea nitrogen 
(BUN), creatinine, creatinine clearance, albumin, total protein, alkaline phosphatase, 
bilirubin (total, nonconjugated), aspartate aminotransferase (AST)/serum glutamic 
oxaloacetic transaminase (SGOT), ALT/ serum glutamic pyruvic transaminase
(SGPT), lactic dehydrogenase (LDH) and uric acid - central laboratory assessment 
should be performed within 4 weeks prior to Dose 1 Day 1
∀
Urinalysis: microalbumin, creatinine, microalbumin/creatinine ratio (morning void; 
central lab) - central laboratory assessment should be performed within 4 weeks prior
to Dose 1 Day 1
∀
MRI for LIC (T2* or R2, mg/g dw). The same MRI technique should be used within 
a subject throughout the study duration.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
63
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
∀
MRI or abdominal ultrasound for spleen measurement, unless splenectomized. If MRI 
is used: the spleen volume (cm3) should be measured in the same acquisition as the 
MRI for LIC, if possible. If abdominal ultrasound is used for spleen measurement, the 
longest longitudinal dimension and width should be taken.
∀
MRI for myocardial iron (T2*; ms)
∀
Bone mineral density by dual energy x-ray absorptiometry (DXA) scan - lumbar 
spine and total hip.
∀
QoL Questionnaire (TranQoL; SF36) - assessment should be performed within 4 
weeks prior to Dose 1 Day 1
∀
HRU
∀
Serum ferritin – one central laboratory assessment should be performed within 4 
weeks prior to Dose 1 Day 1. Record available data from local laboratory 
assessments on serum ferritin for at least 12 weeks prior to randomization.
∀
 
6.1.1.
Re-screening
If a subject fails screening, subject can be re-screened as per Investigator discretion. Re-
screening more than one time is allowed. A new subject number will be assigned by IRT. All 
screening assessments performed until the subject is declared to be a screen fail (12 weeks after 
the ICF signature) can be entered in the eCRF under the new assigned subject ID, if these are 
within the validity windows indicated as per Table 3, Screening/Run-in, ie:
∀
All laboratory assessments indicated in the Table 3 “within 4 wks prior Dose 1 Day 
1” will be considered as valid if not exceeding 4 weeks of the new planned 
randomization date. If outside of this window, the assessment should be repeated.
∀
All other assessments for which there is no restriction indicated in Table 3, will be 
considered as valid if not exceeding 12 weeks of the new planned randomization date. 
If outside of this window, the assessment should be repeated.
∀
However, abnormal assessments that caused ineligibility of the subject must always 
be repeated.
6.2.
Treatment Period
The subject will begin treatment upon acknowledgement of eligibility by the Sponsor. The 
subject must start treatment approximately 12 weeks from signing the informed consent form 
(ICF).  An administrative window of additional 7 days is allowed for administration of Dose 1. 
For all subsequent visits, an administrative window of ± 3 days is permitted.  If screening 
assessments are performed within 72 hours of Dose 1 Day 1, safety laboratory assessments do
not need to be repeated at Dose 1 Day 1, except hematology and blood chemistry assessments.
Subjects will receive their first SC dose of luspatercept or placebo on Day 1 of each dosing 
cycle.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
64
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Treatment is administered every 21 days, and will occur as described in Section 7.2.
The following evaluations will be performed at the frequency specified in the Table of Events,
Table 3. The evaluations should be performed prior to dosing on the visit day, as applicable, 
unless otherwise specified:  
∀
Iron chelating therapies: record on an ongoing basis (as detailed in Section 6.1). 
∀
Other concomitant medications/therapies: such as surgery, radiation, systemic or any 
other therapy for the subject’s disease - record on an ongoing basis. 
∀
Concomitant procedures - record on an ongoing basis. 
∀
Transfusion assessment - including Hb levels prior to each transfusion, the number of 
units transfused, the dates of transfusion. If available, the volume transfused in mL at 
each transfusion and Hct of the transfused unit should also be reported. Record the 
transfusion assessments on an ongoing basis. In addition, as detailed in Section 6.1, a 
subject diary will be available (refer to Section 6.1).
∀
Adverse event assessment - record on an ongoing basis (refer to Section 6.1 and 
Section 10 for additional information). 
∀
Malignancy and Pre-Malignancy Reporting (refer to Section 6.1 and Section 10.5.2
for additional information)
∀
Vital signs (as detailed in Section 6.1) 
∀
ECOG performance status
∀
Weight 
∀
12-lead electrocardiogram (ECG) – read locally
∀
Cardiac Doppler echocardiography, MUGA or MRI- left ventricular ejection fraction 
(LVEF)
∀
Urine or serum medically supervised pregnancy test with a minimum sensitivity of 25 
mIU/mL for FCBP at Day 1 of each dose schedule (with the exception of the first day 
of dosing in dose schedule 1 if performed during Screening within 72 hours of Day 1) 
∀
For female subjects – menstrual status
∀
Hematology assessments (as detailed in Section 6.1) 
∀
Serum chemistry (as detailed in Section 6.1) 
∀
Urinalysis: microalbumin, creatinine, microalbumin/creatinine ratio (morning void; 
central lab)
∀
Serum erythropoietin 
∀
PK and ADA – refer to Section 6.8 and 6.9
∀
MRI for LIC (T2* or R2, mg/g dw). The same MRI technique should be used within 
a subject throughout the study duration.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
65
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
∀
MRI or abdominal ultrasound for spleen measurement, unless splenectomized (as 
detailed in Section 6.1).
∀
MRI for myocardial iron (T2*; ms)
∀
Bone mineral density of total hip and lumbar spine by DXA scan(as detailed in 
Section 6.1) 
∀
QoL self-administered questionnaire TranQoL, SF36
∀
HRU
∀
Serum ferritin 
∀
∀
∀
Administration/ Accountability of luspatercept/placebo on Day 1 of each dose cycle
6.2.1.
Dose Delays in Treatment Period
In case of dose delay (refer to Table 5), the clinical assessments and procedures to be performed
include but are not limited to:
∀
All planned Day 1 assessments should be performed and appropriate samples sent to 
the central laboratory, regardless of the dose delay.
∀
If dose delay is due to an AE, a laboratory or vital signs abnormality (refer to 
Table 5, Dose Delay, Dose Reduction and Discontinuation Guidelines, 
Section 7.2.1.2), repeat any clinically indicated assessment by local laboratory at a 
frequency decided by the Investigator until the subject meets either the treatment 
administration criteria or treatment discontinuation criteria, as detailed in Section 7.2
and Section 11.1.
∀
If dose delay is due to increased hemoglobin level (refer to Table 5, Dose Delay, 
Dose Reduction and Discontinuation Guidelines, Section 7.2.1.2), perform 
hematology on Day 1 of dose delay by central laboratory and then at least weekly by 
local lab, until the subject meets either the treatment administration criteria or 
treatment discontinuation criteria, as detailed in Section 7.2 and Section 11.1
∀
PK/ADA samples should be performed on Day 1 of dose delay and before next dose.
∀
At the time of IP administration following a dose delay, perform the scheduled dosing 
visit assessments (laboratory assessments should be performed by central laboratory) 
as detailed in the Table of Events, Table 3, and Section 6.2, regardless of the duration 
of the dose delay.
6.3.
Long-term Treatment Period
All subjects, whether randomized to luspatercept or placebo, who complete the double-blind
treatment period of this study will have the opportunity to enroll in the Long-term Treatment 
Period and continue to receive IP to which subjects have been initially assigned, as described in 
Section 3.1.3. An administrative visit window of ± 5 days is permitted.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
66
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
During the Long-term Treatment Period all laboratory assessments should be measured by 
central laboratory. Data are to be entered in the eCRF.
The assessments and procedures that will be performed during the Long-term Treatment Period
are outlined in the Table of Events (see Table 3) and include but are not limited to:
∀
Iron chelating therapies: record on an ongoing basis (as detailed in Section 6.1). 
∀
Other concomitant medications/therapies: such as surgery, radiation, systemic or any 
other therapy for the subject’s disease - record on an ongoing basis. 
∀
Concomitant procedures - record on an ongoing basis. 
∀
Transfusion assessment - record on an ongoing basis (as detailed in Section 6.1). In 
addition, as detailed in Section 6.1, a subject diary will be available (refer to 
Section 6.1)
∀
Adverse event assessment - record on an ongoing basis (refer to Section 6.1 and 
Section 10 for additional information). 
∀
Malignancy and Pre-Malignancy Reporting (refer to Section 6.1 and Section 10.5.2
for additional information)
∀
Vital signs (as detailed in Section 6.1) 
∀
Weight 
∀
Cardiac Doppler echocardiography, MUGA or MRI - left ventricular ejection fraction 
(LVEF)
∀
Urine or serum medically supervised pregnancy test with a minimum sensitivity of 25 
mIU/mL for FCBP at Day 1 of each dose schedule.
∀
For female subjects – menstrual status
∀
Hematology (as detailed in Section 6.1) 
∀
Serum chemistry (as detailed in Section 6.1) 
∀
Urinalysis: microalbumin, creatinine, microalbumin/creatinine ratio (morning void; 
central lab)
∀
PK and ADA (if applicable) – refer to Sections 6.8 and 6.9
∀
Serum ferritin
∀
MRI for LIC (T2* or R2, mg/g dw). The same MRI technique should be used within 
a subject throughout the study duration.
∀
MRI or abdominal ultrasound for spleen measurement, unless splenectomized (as 
detailed in Section 6.1).
∀
MRI for myocardial iron (T2*; ms)
∀
Bone mineral density of total hip and lumbar spine by DXA scan(as detailed in 
Section 6.1) 
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M

EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
67
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
∀
QoL self-administered questionnaire TranQol; SF36
∀
HRU
∀
Administration / Accountability of luspatercept on Day 1 of each dose
6.3.1.
Dose Delays in Long-term Treatment Period
In case of dose delay (refer to Table 5), the clinical assessments and procedures to be performed
include but are not limited to:
∀
All planned Day 1 assessments should be performed regardless of the dose delay.
∀
If dose delay is due to an AE, a laboratory or vital signs abnormality (refer to 
Table 5, Dose Delay, Dose Reduction and Discontinuation Guidelines, 
Section 7.2.1.2), repeat any clinically indicated assessment by local laboratory at a 
frequency decided by the Investigator until the subject meets either the treatment 
administration criteria or treatment discontinuation criteria, as detailed in Section 7.2
and Section 11.1.
∀
If dose delay is due to increased hemoglobin level (refer to Table 5, Dose Delay, 
Dose Reduction and Discontinuation Guidelines, Section 7.2.1.2), perform 
hematology on Day 1 of dose delay by central laboratory and then at least weekly by 
local lab until the subject meets either the treatment administration criteria or 
treatment discontinuation criteria, as detailed in Section 7.2 and Section 11.1.
∀
At the time of IP administration following a dose delay, perform the scheduled dosing 
visit assessments (laboratory assessments should be performed by central laboratory)  
as detailed in the Table of Events, Table 3, and Section 6.3, regardless of the duration 
of the dose delay.
6.4.
Open-label Phase
During the Open-label Phase, the following evaluations will be performed at the frequency 
specified in the Table of Events, Table 3. The evaluations should be performed prior to dosing on 
the visit day, as applicable, unless otherwise specified. An administrative visit window of ± 5
days is permitted.
Only subjects who, at the time of unblinding, are in Post-treatment Follow-Up and are on 
placebo, will perform the following assessments and procedures in addition to the procedures 
and assessments that will be performed by subjects who are continuing the treatment with 
luspatercept after the unblinding of the study:
∀
Assessment of eligibility (only subjects who are in the Post-treatment Follow-up who 
were treated with placebo during the double-blind treatment and discontinued the IP). 
Inclusion criteria numbers 6 and 7 and exclusion criteria numbers 1-10, 15-17 and 21 must 
be met at Dose 1 Day 1 
∀
Iron chelating therapies: including type of iron chelating therapy, period of treatment (ie, 
dates) and dose changes 24 weeks prior to Dose 1 Day 1 with luspatercept in the Open 
label Phase and record on ongoing basis (as detailed in Section 6.1). 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
68
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
∀
Prior medications/therapies: 24 weeks prior to Dose 1 Day 1 of luspatercept
∀
Prior procedures 24 weeks prior to Dose 1 Day 1 of luspatercept
∀
Transfusion assessment – 24 weeks RBC transfusion history prior to Dose 1 Day 1 of the 
Open-label Phase of luspatercept including Hb levels prior to each transfusion, the number 
of units and or volumes transfused, and the dates of transfusion. If available, the Hct of the 
transfused unit should be collected, as well as the age when the subject started regular 
transfusion. These retrospective data will be recorded in the subject’s electronic case 
report form (eCRF).
∀
Serum ferritin: 24 weeks prior to Dose 1 Day 1 of luspatercept.
∀
ECOG performance status (Appendix B) 
∀
12-Lead Electrocardiogram – read locally
∀
Females: Serum medically supervised pregnancy test with a minimum sensitivity of 25 
mIU/mL for FCBP at Day 1 Dose 1 of luspatercept
∀
Serum chemistry (as detailed in Section 6.1)
∀
Urinalysis: microalbumin, creatinine, microalbumin/creatinine (as detailed in Section 6.1)
All subjects, ie, subjects who are continuing the treatment with luspatercept after the 
unblinding of the study, and subjects who are starting the treatment with luspatercept after 
received placebo in the double-blind treatment, will perform the following assessments and 
procedures:
∀
Iron chelating therapies: record on an ongoing basis (as detailed in Section 6.1).
∀
Concomitant medications/therapies: such as surgery, radiation, systemic or any other 
therapy for the subject’s disease - record on ongoing basis. 
∀
Concomitant procedures - record on ongoing basis. 
∀
Transfusion assessment - record on an ongoing basis (as detailed in Section 6.1). In 
addition, as detailed in Section 6.1, a subject diary will be available (refer to Section 6.1)
∀
Adverse event assessment - record on an ongoing basis as detailed in Section 6.1 and 
Section 10.
∀
Malignancy and Pre-Malignancy Reporting (refer to Section 6.1 and Section 10.5.2 for 
additional information)
∀
Vital signs (as detailed in Section 6.1) 
∀
Weight 
∀
Female subjects of childbearing potential: Urine or serum medically supervised pregnancy 
test with a minimum sensitivity of 25 mIU/mL for FCBP at Day 1 of each dose 
∀
Female subjects of childbearing potential: menstrual status
∀
Hematology (as detailed in Section 6.1) 
∀
ADA (if applicable) – refer to Section 6.9 and Table 3
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tete

EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
69
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
∀
HRU
∀
Administration of luspatercept on Day 1 of each dose
∀
Only at Week 96 post first dose, if applicable, ie, for subjects who entered Open-label 
Phase prior to reaching Week 96 in the Long-term Treatment Period:
o
MRI for LIC (mg/g dw) (as detailed in Section 6.1) - only at week 96 post 
first dose, if applicable.
o
MRI for myocardial iron (T2*; ms) - only at week 96 post first dose, if 
applicable.
o
MRI or abdominal ultrasound for spleen measurement (as detailed in 
Section 6.1) - only at week 96 post first dose, if applicable.
o
Bone imaging DXA scan (as detailed in Section 6.1) - only at week 96 post 
first dose, if applicable.
6.4.1.
Dose Delays in Open-label Treatment Period
In case of dose delay (refer to Table 5), the clinical assessments and procedures to be performed
include but are not limited to:
∀
If dose delay is due to increased hemoglobin level (refer to Table 5, Dose Delay, 
Dose Reduction and Discontinuation Guidelines, Section 7.2.1.2), perform 
hematology on Day 1 of dose delay by central laboratory and then at least weekly by 
local laboratory until the subject meets either the treatment administration criteria or 
treatment discontinuation criteria, as detailed in Sections 7.2.1.2, 7.2.1.3 and 11.1
∀
If dose delay is due to an AE, laboratory or vital signs abnormality (refer to 
Table 5, Dose Delay, Dose Reduction and Discontinuation Guidelines, Section 
7.2.1.2), repeat any clinically indicated assessment by local laboratory at a frequency 
decided by the Investigator until the subject meets either the treatment administration 
criteria or treatment discontinuation criteria, as detailed in Sections 7.2.1.3 and 11.1
6.5.
Treatment Discontinuation
Reasons for treatment discontinuation are provided in Section 11.  An end of treatment 
evaluation will be performed for subjects who are withdrawn from treatment for any reason as 
soon as possible after the decision to permanently discontinue treatment has been made.
Subjects who discontinue early from treatment will proceed to the Treatment Discontinuation 
visit within 22 days of the last dose of study drug, or, soon after the decision to discontinue the 
study drug, if this occurred more than 22 days after the last dose of study drug.
The assessments and procedures that will be performed at Treatment Discontinuation are 
outlined in the Table of Events (see Table 3) and include but are not limited to:
∀
Iron chelating therapies: record on an ongoing basis (as detailed in Section 6.1). 
∀
Other concomitant medications/therapies: such as surgery, radiation, systemic or any 
other therapy for the subject’s disease - record on an ongoing basis. 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
70
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
∀
Concomitant procedures - record on an ongoing basis.
∀
Transfusion assessment - record on an ongoing basis (as detailed in Section 6.1). In 
addition, as detailed in Section 6.1, a subject diary will be available (refer to 
Section 6.1)
∀
Adverse event assessment - record on an ongoing basis (refer to Section 6.1 and 
Section 10 for additional information). 
∀
Malignancy and Pre-Malignancy Reporting (refer to Section 6.1 and Section 10.5.2
for additional information)
∀
Vital signs (as detailed in Section 6.1)
∀
Weight 
∀
Urine or serum medically supervised pregnancy test with a minimum sensitivity of 25 
mIU/mL for FCBP 
∀
For female subjects only - menstrual status
∀
Hematology (as detailed in Section 6.1) 
∀
Serum chemistry (as detailed in Section 6.1) 
∀
Urinalysis: microalbumin, creatinine, microalbumin/creatinine ratio (morning void; 
central lab)
∀
12-lead electrocardiogram (ECG) – read locally
∀
PK – refer to Section 6.8
∀
ADA – refer to Section 6.9
∀
Serum erythropoietin
∀
MRI for LIC (T2* or R2, mg/g dw). The same MRI technique should be used within 
a subject throughout the study duration.
∀
MRI or abdominal ultrasound for spleen measurement, unless splenectomized (as 
detailed in Section 6.1)
∀
MRI for myocardial iron (T2*; ms)
∀
Bone mineral density of total hip and lumbar spine by DXA scan (as detailed in 
Section 6.1)
∀
Serum ferritin
∀
∀
∀
HRU
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
71
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
6.6.
Post-treatment Follow-up Period
At the end of the Treatment Period, Long-term Treatment Period, or Open-label Phase, as 
applicable, all subjects who discontinue treatment will be followed for an additional 156 weeks
from last dose of IP received.  Subjects will be monitored on week 9, followed by 24, 48, 72, 96, 
120, 144 after the last dose up to week 156. End of study visit, will coincide with week 96, refer 
to Section 6.7. A visit window of ± 7 days is permitted.
The assessments and procedures that will be performed during this period are outlined in the 
Table of Events (see Table 3) and include but are not limited to:
Only for Follow-Up Week 9 post last dose, the below assessments will be performed:
∀
Iron chelating therapies: record on an ongoing basis up to week 9 Post-last dose (as 
detailed in Section 6.1).
∀
Other concomitant medications/therapies: such as surgery, radiation, systemic or any 
other therapy for the subject’s disease - record on an ongoing basis up to week 9 Post-
last dose.. 
∀
Concomitant procedures - record on an ongoing basis up to week 9 Post-last dose.. 
∀
Transfusion assessment - record on an ongoing basis up to week 9 Post-last dose (as 
detailed in Section 6.1). In addition, as detailed in Section 6.1, a subject diary will be 
available (refer to Section 6.1).
∀
Adverse event assessment regardless of causality- record on an ongoing basis up to 
Week 9 Post-last dose, and only related AE from Week 9 Post-last dose up to End of 
Study (refer to Section 6.1 for additional information). 
∀
Malignancy and Pre-Malignancy Reporting - regardless of causality until End of 
Study. (refer to Section 6.1 and Section 10.5.2 for additional information)
∀
Vital signs (as detailed in Section 6.1) 
∀
Weight 
∀
Urine or serum medically supervised pregnancy test with a minimum sensitivity of 25 
mIU/mL for FCBP 
∀
For female subjects only - menstrual status
∀
Hematology (as detailed in Section 6.1) 
∀
Serum chemistry (as detailed in Section 6.1) 
∀
Urinalysis: microalbumin, creatinine, microalbumin/creatinine ratio (morning void; 
central lab)
∀
PK and ADA – refer to Sections 6.8 and 6.9
∀
Serum ferritin 
∀
HRU
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
72
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Post-treatment Follow-up monitoring at Week  24, 48, 72, 96, 120, 144 post last dose –
assessments and procedures, that will be performed during this period are outlined in the Table 
of Events (see Table 3) and include but are not limited to:
∀
Adverse event assessment - record all AEs regardless of causality on an ongoing basis
up to week 9 Post-last dose, and only related AE from week 9 Post-last dose up to 
End of Study (refer to Section 6.1 for additional information).
∀
Malignancy and Pre-Malignancy Reporting - regardless of causality as SAEs until 
End of Study. Subjects are required  to see the Investigator at least every 24 weeks to 
assess for malignancy and pre-malignancy, as per standard of care (refer to 
Section 10.5.2 for additional information)
6.6.1.
Early Discontinuation Follow-up Period
Subjects who discontinue before completing the double-blind treatment period (48 weeks) will 
continue to be monitored on week 9, followed by week , 24, 48, 72, 120, 144 after the last dose.
The assessments and procedures that will be performed during this Early Discontinuation 
Follow-up Period are outlined in the Table of Events (see Table 3) and include but are not 
limited to:
∀
Iron chelating therapies: record on an ongoing basis (as detailed in Section 6.1) - this 
parameters is to be reported up to 48 weeks Post Dose 1 Day 1 or Week 9 post last 
dose whichever is the later date.
∀
Other post-treatment medications/therapies: such as surgery, radiation, systemic or 
any other therapy for the subject’s disease - record on an ongoing basis - these 
parameters are to be reported up to 48 weeks Post Dose 1 Day 1 or Week 9 post last 
dose whichever is the later date. 
∀
Post-treatment procedures - record on an ongoing basis - these parameters are to be 
reported up to 48 weeks Post Dose 1 Day 1 or Week 9 post last dose whichever is the 
later date. 
∀
Transfusion assessment - record on an ongoing basis (as detailed in Section 6.1). In 
addition, as detailed in Section 6.1, a subject diary will be available (refer to 
Section 6.1). - these parameters are to be reported up to 48 weeks Post Dose 1 Day 1 
or Week 9 post last dose whichever is the later date.
∀
Adverse event assessment - record AEs regardless of causality on an ongoing basis 
until 9 weeks post last dose, related AE to be reported from week 9 Post-last dose 
until End of Study.
∀
Malignancy and Pre-Malignancy Reporting - regardless of causality as SAEs until 
End of Study. Subjects are required  to see the Investigator at week 9 and at least 
every 24 weeks thereafter to assess for malignancy and pre-malignancy, as per 
standard of care (refer to Section 10.5.2 for additional information)
∀
MRI for LIC (T2* or R2, mg/g dw). The same MRI technique should be used within 
a subject throughout the study duration.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
73
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
∀
MRI for abdominal ultrasound spleen measurement, unless splenectomized (as 
detailed in Section 6.1)
∀
MRI for myocardial iron (T2*; ms).
∀
Bone mineral density of total hip and lumbar spine by DXA scan (as detailed in 
Section 6.1).
∀
HRU - this parameter is to be reported up to 48 weeks Post Dose 1 Day 1 or Week 9 
post last dose whichever is the later date.
∀
Vital signs (as detailed in Section 6.1) 
∀
Weight
6.7.
End of Study Visit
Reasons for premature End of Study are provided in Section 11.2.  The End of Study visit is the 
final scheduled visit for this study and can coincide with week 156 Post last dose.
The assessments and procedures that will be performed during the End of Study are outlined in 
the Table of Events (see Table 3) and include but are not limited to:
∀
Adverse event assessment - record AEs regardless of causality on an ongoing basis up 
to week 9 Post-last dose, and only related AE up to End of Study (refer to Section 6.1
for additional information). 
∀
Malignancy and Pre-Malignancy Reporting - regardless of causality as SAE until End 
of Study (refer to Section 10.5.2 for additional information).
The reason for discontinuation should be recorded in the eCRF and in the source 
documents.
6.8.
Pharmacokinetics
Serum samples will be collected to analyze luspatercept concentrations (PK) in all subjects as 
indicated in Table 3.  Collection, processing, and shipping procedures for blood PK samples are 
provided in the study reference guide.
∀
Treatment Period: Doses 1 to 16:  at predose (Dose 1 Day 1, must be collected before 
the first dose), Dose 2 Day 1, Dose 3 Day 1, Dose 4 Day 1, Dose 5 Day 1, Dose 6 
Day 1, Dose 6 Day 8, Dose 6 Day 15, Dose 8 Day 1, Dose 10 Day 1, Dose 12 Day 1, 
Dose 14 Day 1, and Dose 16 Day 1
∀
Long-term Treatment Period: every 6 doses. ADA/PK sampling per Investigator’s or 
Sponsor’s discretion is allowed and should be recorded as an unscheduled visit
6.9.
Anti-Drug Antibody
Serum samples will be collected for assessment of anti-drug antibodies (ADA) in all subjects.  
The maximum ADA monitoring period will be two years from dose 1 day 1 of double-blind 
Treatment Period.  An additional blood draw is not needed for the anti-luspatercept antibody test.  
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
74
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
The anti-luspatercept antibody test will be conducted for the following visits utilizing the PK 
samples obtained at the same visit:
∀
Treatment Period: Doses 1 to 16:  Predose (Dose 1 Day 1, must be collected before 
the first dose), Dose 2 Day 1, Dose 4 Day 1, Dose 6 Day 1, Dose 8 Day 1, Dose 12 
Day 1, Dose 16 Day 1.
∀
Long-term Treatment Period: every 6 doses.
∀
Open Label Phase: for placebo-cross-over subjects, only if positive at unblinding, 
continue every 6 doses up to 2 years from Dose 1 Day 1 of the double-blind 
Treatment Period. For subjects continuing treatment with luspatercept, only if 
positive at unblinding, every 6 doses up to 2 years from Dose 1 Day 1 of the double 
blinded treatment period..
∀
Post-treatment Follow-up (starting at Follow-up Week 9):
o
Before unblinding: every 24 weeks post last dose until the unblinding for up 
to two years from Dose 1 Day 1 of double-blind Treatment Period.
o
After unblinding, ADA monitoring every 24 weeks post last dose, only if 
subjects’ last available ADA is positive and they have not reached the 2-year 
maximum limit for ADA monitoring.
ADA/PK sampling per Investigator’s or Sponsor’s discretion is allowed and should be recorded 
as an unscheduled visit.
 
 
 
 
6.11.
Quality of Life
∀
TranQoL – Subjects will be asked to complete the quality of life questionnaire 
TranQoL at screening, and at Weeks 12, 24, 36 and 48 post Day 1 Dose 1, and every 
12 weeks during the Long-term Treatment Period.
∀
SF-36 - Subjects will be asked to complete the quality of life questionnaire SF-36 at 
screening, and at Weeks 12, 24, 36 and 48 post Day 1 Dose 1, and every 12 weeks 
during the Long-term Treatment Period.
6.12.
Screen Failures 
For all subjects determined to be screen failures, the following information is to be captured in 
the subject’s source documents and appropriate eCRF page(s): the date informed consent 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
75
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
document (ICD) was signed, demographics, the reason subject did not qualify for the study, and 
the Investigator’s signature for the eCRF pages. The adverse events experienced by screen 
failure subjects will be collected from the date of signing consent to the day the subject is 
confirmed as screen failure. Relevant information will also be recorded on the Screening Log.
CCI

EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
76
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
7.
DESCRIPTION OF STUDY TREATMENTS
7.1.
Description of Investigational Product(s)
Luspatercept will be provided by the Sponsor. Luspatercept for injection is formulated as a 
sterile, preservative-free, lyophilized cake/powder. Luspatercept for injection is available in 2 
strengths, and when reconstituted, consists of 50 mg/mL luspatercept in a 10 mM citrate buffer-
based solution (10 mM citrate, pH 6.5, 9% sucrose, 0.02% polysorbate 80). The drug product is 
packaged in a 3 mL glass vial in the following strengths:
∀
25 mg/vial: The 25 mg/vial presentation contains 37.5 mg of Luspatercept protein. After 
reconstitution with 0.68 mL water for injection (WFI), each single-use vial will deliver at 
least 0.5 mL of 50 mg/mL luspatercept (25 mg)
∀
75 mg/vial: The 75 mg/vial presentation contains 87.5 mg of Luspatercept protein. After 
reconstitution with 1.6 mL WFI, each single-use vial will deliver at least 1.5 mL of 
50 mg/mL luspatercept (75 mg)
The recommended storage condition for luspatercept for injection (25 mg/vial and 75 mg/vial; 
lyophilized powder formulation) is 2-8°C. It is recommended that the reconstituted luspatercept 
for injection, at room temperature, be administered immediately.  However, it may be held for up 
to 10 hours at 2°C to 8°C.
If not used immediately, the total in-use time of the reconstituted luspatercept for injection, from 
reconstitution to administration, must not exceed 10 hours.
Samples of luspatercept drug product, held at the recommended storage condition, have been 
shown to be stable through the labeled shelf-life.
Placebo to be used in the study will be sterile normal saline (0.9% sodium chloride for injection) 
administered as a SC injection.  Sterile, normal saline will be prepared in syringes by the 
investigational site’s designated individuals to match the active syringe. The doctor and subject
will be blinded.  The manufacturer’s directions for placebo storage and handling are to be 
followed, as are standard clinical practices for ensuring sterility of the placebo.
7.2.
Treatment Administration and Schedule
Luspatercept or placebo will be administered as a subcutaneous (SC) injection to subjects by the 
study staff at the clinical site and administration will be documented in the subject’s source 
record.  Subcutaneous injections will be given in the upper arm, thigh, and/or abdomen.
Calculated doses requiring reconstituted volume greater than 1.2 mL should be divided into 
separate similar volume injections across two separate sites using the same anatomical location 
but on opposite sides of the body (example left thigh and right thigh). The maximum volume per 
SC injection should not exceed 1.2 mL. The maximum total dose per administration should not 
exceed 120 mg, which results in 2.4 mL maximum total volume after reconstitution. The 
injection sites can be rotated according to Investigator judgment, and the injections can be given 
in the following order as needed, for example: 1) right upper arm, 2) left upper arm, 3) right 
upper thigh, 4) left upper thigh.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
77
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Subjects will be assigned to treatment as per one of the following regimens:
∀
Luspatercept starting dose level 1 mg/kg SC once every 21 days
∀
Placebo SC once every 21 days
The investigational product should be administered according to the following criteria:
∀
Pre-treatment/ pre-transfusion Hb value is < 11.5 g/dL and increase of Hb ≤2.0
g/dL compared to the pre-dose Hb of Day 1 of the previous treatment dose cycle, and
∀
Any related adverse events must be < Grade 2 according to NCI CTCAE criteria
(Appendix C)
∀
WBC < 3 x baseline. Corrected WBC values should be used to establish the baseline 
WBC.  Baseline is equal to the highest WBC value between Screening WBC and 
Study Dose 1 Day 1.
∀
Leukopenia, neutropenia and/or thrombocytopenia should be < Grade 3, as per NCI 
CTCAE criteria (Appendix C)
∀
< 50 % increase from baseline in transfusion burden in combination with shift from 
baseline (worsening) of < 2 grades in leukopenia, neutropenia or thrombocytopenia
Please refer to Table 5 for guidelines on dose modifications and dose delays.
Subjects must have Hb assessed and results available prior to each study drug administration. If a 
transfusion occurred prior to dosing, the pre-transfusion Hb should be considered for dosing 
purposes (ie, Hb ≥ 14 days post- transfusion).
Subjects must have blood pressure assessed prior to each study drug administration.  Blood 
pressure values should be confirmed by means of two readings obtained approximately 10
minutes apart with the subject seated for approximately 10 minutes prior to initial reading.
Safety laboratory analyses and all assessments will be performed centrally (except otherwise 
stated in Table 3) during the double-blind Treatment Period.  However, in addition to the blood 
draw or urine sampling for central analysis, blood draw or urine sampling for local laboratory 
assessments are only allowed in the following circumstances: cases when timely results are 
needed - eg, randomization, study treatment dosing decisions, hematology assessments between 
clinic visits, adverse event.  Local laboratory data should be collected in the eCRF if relevant to 
dose administration, modification and AE, or when no central lab results were obtained.
Please refer to Table 5 for guidelines on dose modifications and dose delays.
7.2.1.
Dose Modifications: Dose Titration, Dose Reduction and Dose Delay
7.2.1.1.
Dose Titration
Subjects may be dose-titrated to 1.25 mg/kg, but the maximum total dose should not exceed 120 
mg, during the treatment period as well as during the Long-term Treatment Period and Open-
label Phase, as long as a dose delay or reduction is not required (see Section 7.2.1.2). The dose 
titration criteria are defined as follows:
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
78
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
∀
Transfusion reduction over at least two dose cycles (~6 weeks) is < 33%, compared to 
the transfusion burden (units/wk) at baseline, or
∀
Transfusion reduction over at least two dose cycles (~6 weeks) is ≥33 but ≤50% 
compared to baseline, at the discretion of the Investigator.
After safety and efficacy data review, the sponsor may allow dose titration following special 
requests, such as, but not limited to, subjects who have been dose reduced once, but lost the 
response to treatment.
Starting dose with dose titration and reductions are presented below for reference (Table 4).
Table 4:
Starting Dose Level with Dose Reductions and Dose Titration
3rd Dose 
Reduction
(~ 25 %)
2nd Dose 
Reduction
(~ 25 %)
1st Dose 
Reduction
(~ 25 %)
Starting Dose
Level
1st Dose
Titration
0.45 mg/kg
0.6 mg/kg
0.8 mg/kg
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7.2.1.2.
Dose Delay and Dose Reduction 
Dose delay of luspatercept from the planned dosing schedule may occur due to increased 
hemoglobin or adverse events. Table 5 provides guidelines for dose modifications and dose 
delay.  
Subjects can experience a dose reduction based on the change in mean Hb level (Hb not 
influenced by a transfusion) with respect to the last dose, as well as related adverse events, as 
detailed in Table 5. Hemoglobin not influenced by a transfusion should be considered for 
dosing, delays and discontinuation actions related to luspatercept.  Hemoglobin not influenced by 
a transfusion is considered a Hb within 14 days post-transfusion. If a subject is experiencing a 
dose delay due to Hb increase, Hb measurement should occur every week. 
If dose delay is 15 weeks or longer from the previous dose administered, including cases of 
elective surgery/hospitalization, the treatment should be discontinued. Dose delay for AE 
unrelated to the study drug, as per discretion of the Investigator are allowed. Assessments to be 
performed during the dose delay period are detailed in Section 6.
Celgene or its authorized representative should be notified of dose modification or interruption 
within 24 hours. 
Dose reduction and dose delays guidelines are detailed in Table 5.
Table 5:
Dose Delay, Dose Reduction and Discontinuation Guidelines:
Event at the Day of Dosing
Action
Any related AE = Grade 2a
Dose delayc until resolved to ≤ Grade 1 or baseline
Any related AE ≥ Grade 3a
Dose delayc until resolved to ≤ Grade 1 or baseline, and then 
reduce dose by 25%d
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
79
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Table 5:
Dose Delay, Dose Reduction and Discontinuation Guidelines: (Continued)
Event at the Day of Dosing
Action
> 2 dose reductions due to related AEa
Discontinue treatment
Increase in Hb >2.0 g/dL compared to 
pre-dose Hb of Day 1 of the previous 
treatment dose cycleb
Reduce dose by 25%d if ΔHb not influenced by RBC 
transfusions
Hb ≥ 11.5 g/dLb
Dose delay until Hb ≤11.0 g/dL 
Worsening of Anemia
A ≥ 50 % increase from baseline in 
transfusion burden in combination with 
an unexplained shift from baseline 
(worsening) of ≥ 2 gradesi in 
leukopenia, neutropenia or 
thrombocytopeniah.
Dose delayc and repeat WBC, neutrophils and platelets 
weekly for two consecutive weeks. 
∀If WBC, neutrophils and platelets are resolved to ≤ 
Grade 1 or baseline, continue with dosing at the same 
dose level. 
∀If WBC, neutrophils and platelets are Grade 2 and 
above baseline, then continue with dose delay until 
resolution to ≤ Grade 1 and evaluate for alternative 
explanations of cytopenia as per standard clinical 
practice. 
∀If shift (worsening) of ≥ 2 grades is maintained for ≥ 
14 days or thrombocytopenia does not improve to < 
Grade 2 within 14 days and no alternative explanation 
is identified, then perform bone marrow assessment. 
o
If hematologic malignancy is confirmed, 
discontinue treatmentg
o
If hematologic malignancy is not confirmed, then 
discuss future dosing with medical monitor.
WBC
WBC counte ≥2X baseline in the
absence of an associated condition (eg, 
infection or concomitant 
corticosteroid use)
Continue treatment, repeat WBC within 1 week
∀If repeat WBC remains ≥ 2 X above baseline 
Investigator should assess the cause of increase to 
exclude hematologic malignancy as per standard 
clinical practice. 
∀If hematologic malignancy is confirmed, 
discontinue treatment.g
WBC counte ≥ 3X baseline 
Dose delayc with weekly WBC monitoring until WBC 
count <3 X baseline. 
∀Investigator should assess the cause of increase per 
standard clinical practice to exclude hematologic 
malignancy. 
∀If hematologic malignancy is confirmed, 
discontinue treatment.g
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
80
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Table 5:
Dose Delay, Dose Reduction and Discontinuation Guidelines: (Continued)
a Possibly, probably or definitely related.
b Based on the pre-treatment Hb value not influenced by transfusion (ie, ≥ 14 days post- transfusion); Hb should be 
rechecked weekly during dose delay.
c If dose delay is 15 weeks or longer from the prior dose administration, treatment should be discontinued.
d Refer to Table 4 for dose reductions.
e Central laboratory corrected WBC values must be used for confirming the Investigator decision, which may be 
based on the local lab result.  The baseline WBC is defined as highest WBC value between Screening WBC and 
Study Dose 1 Day 1.
f Grade 3 Leukocytosis (as per CTCAE, ie, WBC above 100K) should be based on Central Laboratory values, as 
applicable.
g For full list of events triggering discontinuation, see Section 11 of the protocol.
h For reference, as per CTCAE : Grade 1 Leukopenia : < LLN – 3000/mm3; Grade 1 Neutropenia : < LLN –
1500/mm3; Grade 1 Thrombocytopenia :< LLN – 75’000/mm3; Grade 2 Leukopenia : < 3000 – 2000 / mm3; 
Grade 2 Neutropenia : < 1500 – 1000 / mm3; Grade 2 Thrombocytopenia :< 75’000 – 50’000 / mm3.
i Grade 3 Leukopenia (as per CTCAE, < 2000 - 1000/mm3), Neutropenia (as per CTCAE, ie,  < 1000 - 500/mm3) 
and Thrombocytopenia ( < 50,000 - 25,000/mm3).
7.2.1.3.
Overdose 
Overdose, as defined for this protocol, refers to luspatercept dosing only.  On a per dose basis, an
overdose is defined as the following amount over the protocol-specified dose of luspatercept 
assigned to a given subject, regardless of any associated adverse events or sequelae.  
SC 10% over the protocol-specified dose
On a schedule or frequency basis, an overdose is defined as anything more frequent than the 
protocol required schedule or frequency.  Complete data about drug administration, including 
any overdose, regardless of whether the overdose was accidental or intentional, should be 
reported in the eCRF.  See Section 10.1 for the reporting of adverse events associated with 
overdose.
Event at the Day of Dosing
Action
Grade ≥ 3 Leukopenia, neutropenia 
and/or thrombocytopeniai
Dose delayc and, repeat assessment weekly for two 
consecutive weeks
∀Investigator should assess the cause of cytopenia 
per standard clinical practice to exclude 
hematologic malignancy.
∀If WBC, neutrophils and platelets resolved to ≤ 
Grade 1, continue with dosing at the same dose 
level. 
∀If WBC, neutrophils and platelets ≥ Grade 2 and 
above baseline sustained for ≥ 14 days perform 
bone marrow assessment.
o
If hematologic malignancy is confirmed, 
discontinue treatmentg
o
If hematological malignancy is not confirmed, 
then discuss future dosing with a medical 
monitor.
Grade 3 Leukocytosisf
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
81
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
7.3.
Method of Treatment Assignment
The treatment assignment (randomization) will occur at the end of the Screening Period, once all 
the required screening procedures have been completed and all required data have been 
submitted to the Sponsor or its authorized representative. Upon receiving acknowledgment of 
subjects’ eligibility from the Sponsor or its authorized representative, subject can be assigned for 
treatment using IRT. This study will utilize the IRT for enrollment. 
Designated research personnel at each investigational site will be assigned password protected, 
coded identification numbers which gives them the authorization to call into IRT to enroll 
subjects.  For drug assignment at each dose start and in the event of any dose reduction, dose 
titration site staff must contact IRT to record the new dose level and obtain the new study 
treatment assignment.
The relationship of the randomization number to the subject ID number will be described by a 
randomization algorithm. The randomization algorithm will be employed by the IRT system to 
assign a subject to a treatment based on the prespecified rules, such us double blind study, 
stratified randomization with randomization ratio active vs placebo on a 2:1; subjects will be 
placed into the appropriate stratum per the responses/data entered/collected for questions 
collecting stratification and based on the combination of these data points, the IRT will place the 
subject in the next available slot within the appropriate stratum for that subject. The IRT will be 
utilized to ensure an equal weight central randomization based on randomization method
according to stratification factor defined in Section 3.1, Study Design. The randomization 
number corresponds to a particular treatment arm within a stratum. The randomization number, 
by itself, will not unblind a user to the subject’s treatment. The randomization number should be 
coupled with all the unblinded code information, in order the subject to become unblinded.
7.4.
Packaging and Labeling
The label(s) for luspatercept will include Sponsor name, address and telephone number, the 
protocol number, IP name, dosage form and strength (where applicable), amount of IP per 
container, lot number, expiry date (where applicable), medication identification/kit number, 
dosing instructions, storage conditions, and required caution statements and/or regulatory 
statements as applicable. Additional information may be included on the label as applicable per 
local regulations.
7.4.1.
Blinding
For this trial, all subjects, study site staff and Celgene Corporation representatives with the 
exception of designated individuals (eg, the pharmacist at the investigational site), will remain 
blinded to all treatment assignments until all subjects completed 48 weeks of double-blind 
treatment or discontinue before reaching 48 weeks double-blind treatment, whichever is the 
earlier date, or at the time the study is unblinded (per DMC recommendation) and the data base 
is locked.
The designated site individual (for example the pharmacist) at the investigational site will use a 
syringe (that exactly matches the syringe used for reconstituted luspatercept) and sterile normal 
saline (0.9% sodium chloride for injection) to prepare a matching placebo. Thus, the designated 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
82
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
site individual at the Investigational site will be unblinded and will give Investigators and their 
staff luspatercept and placebo in a blinded manner.
Randomization, drug dispensing, dose reduction/titration, and drug discontinuation will be 
accomplished by an IRT system. Authorized site personnel must contact the IRT for 
randomization, study drug assignment at the beginning of each cycle, to register dose reductions 
or titrations, and treatment discontinuation. Confirmation of each call will be sent to the 
investigational site and Celgene.
For emergency unblinding refer to Section 12.2.
7.5.
Investigational Product Accountability and Disposal 
Accountability for study drug that is administered during the course of the study is the 
responsibility of the Investigator or designee. Investigational clinical supplies must be received 
by a designated person at the clinical site and kept in a secure and temperature-controlled 
location.  The investigational site must maintain accurate records demonstrating dates and 
amounts of study drug received, to whom it was administered (subject-by-subject accounting), 
and accounts of any luspatercept accidentally or deliberately destroyed or returned.  Accurate 
recording of all IP administration will be made in the appropriate section of the subject’s eCRF 
and source documents.  Unless otherwise notified, all vials of study drug, both used and unused, 
must be saved for drug accountability.  The used vials may be discarded, per the institution’s 
standard practice, after drug accountability has been completed by the monitor.  The Investigator 
must return all unused vials of study drug to the Sponsor at the end of the study, or the study 
drug may be destroyed at the clinical site with the permission of the Sponsor.  For either 
scenario, the outcome must be documented on the drug accountability log.  The Sponsor will 
provide direction for the outcome of all unused vials.
Celgene (or designee) will review with the Investigator and relevant site personnel the process 
for investigational product return, disposal, and/or destruction including responsibilities for the 
site versus Celgene (or designee).
7.6.
Investigational Product Compliance
Study drug will be administered as a SC injection at the clinical site by the study staff.  
Monitoring for subject compliance with the treatment regimen is therefore unnecessary.
Accurate recording of all IP administration will be made in the appropriate section of the 
subject’s eCRF and source documents.
The Investigator or designee is responsible for accounting for all IP that is administered during 
the course of the study.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
83
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
8.
CONCOMITANT MEDICATIONS AND PROCEDURES
During screening and throughout the study subjects may take stable doses of medications for 
chronic conditions that are not specifically excluded by the protocol (see Sections 4.2 Inclusion 
Criteria and 4.3 Exclusion Criteria). The Investigator should consult the medical monitor 
regarding any questions about whether a new medication or dosage of existing medication would 
require the patient to discontinue from the study. 
Prior/Concomitant medications will be collected beginning at study Screening/Run-in Period and 
will include all medications taken within 12 weeks prior to Dose 1 Day 1.
For information regarding other drugs that may interact with IP and affect its metabolism, 
pharmacokinetics, or excretion, please see the Investigators Brochure and/or local package insert.
8.1.
Permitted Concomitant Medications and Procedures
8.1.1.
General Concomitant Medication Usage
During screening and throughout the study subjects may take stable doses of medications for 
chronic conditions that are not specifically excluded by the protocol (see Section 4.3 Exclusion 
Criteria).
The Investigator should consult the medical monitor regarding any questions about whether a 
new medication or dosage of existing medication would require the patient to discontinue from 
the study. 
All concomitant treatments, used from 12 weeks prior to first dose of IP until the End of Study 
visit must be reported on the eCRF.  
All prior and concomitant blood and blood products received, iron chelating and 
antihypertensive therapies used from 24 weeks prior to first dose of IP until the End of Study 
visit must be reported on the eCRF.
8.1.2.
Concomitant Medication for Anemia
Concurrent therapy with a new prescription medication related to the treatment of anemia during 
the course of the study must first be discussed with the Medical Monitor prior to administration, 
unless appropriate medical care necessitates that the medication should begin before the Medical 
Monitor can be consulted.
If treatment with hydroxyurea is required during the treatment period, the patient should be 
discontinued from treatment with study drug and enter the follow-up period.
8.1.3.
Iron Chelation Therapy
Concurrent treatment with iron chelation therapy should be used as per product label and 
investigator practice prior to randomization.
8.1.4.
RBC Transfusions
Concurrent treatment for anemia with blood transfusions is allowed, at the discretion of the 
Investigator, for low hemoglobin levels, symptoms associated with anemia (eg, hemodynamic or 
pulmonary compromise requiring treatment) or comorbidity.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
84
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
For any RBC transfusions received during the study, collect hemoglobin values just prior to 
transfusion, the number of units transfused, the dates of transfusion. If available, the volume 
transfused in mL at each transfusion and hematocrit (Hct) of the transfused unit should be 
collected.
Each TD subject will have a “pre-transfusion hemoglobin threshold” for requiring transfusion 
during the study which will be determined based on transfusion history. Baseline pre-transfusion 
hemoglobin threshold will be the mean of all documented pre-transfusion hemoglobin values 
during the 24 weeks prior to Dose 1 Day 1. During treatment, if the pre-transfusion hemoglobin 
level is increased by ≥ 1 g/dL compared to the pre-transfusion hemoglobin threshold for that 
subject, transfusion should be delayed by a minimum of 7 days and/or the number of units 
transfused should be reduced by 1 or more RBC units.
Subjects may be transfused at the Investigator’s discretion for symptoms related to anemia or 
other requirements (eg, infection).
8.2.
Prohibited Concomitant Medications and Procedures
No concurrent treatments with any other investigational agent are allowed.
Treatment with hydroxyurea and anagrelide is not allowed during the Treatment Period (refer 
also to Section 8.1.2).
The use of hematopoietic growth factors will not be allowed during the Treatment Period of the 
study.  However, any subject who requires hematopoietic growth factor treatment during the 
Treatment Period must be discontinued from the study, at which point, hematopoietic growth 
factor treatment is permitted.
Anticoagulant therapies and platelet aggregation inhibitors can be used. However, if these 
therapies are used due to a related AE that would qualify for Treatment Discontinuation as per 
Section 11, the subject should be discontinued from the study treatment. Any anticoagulant 
therapies use for prophylaxis, as well as aspirin and LMW heparin are allowed.
8.3.
Required Concomitant Medications and Procedures
Not applicable.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
85
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
9.
STATISTICAL CONSIDERATIONS
9.1.
Overview
The proposed Phase 3 study is double-blind, randomized, placebo- controlled, multicenter study
to determine the efficacy and safety of luspatercept (ACE-536) plus BSC versus BSC in adults 
who require regular red blood cell transfusion due to !-thalassemia.
The design of the study, including the proposed targeted patient population, study endpoints, and 
statistical plan, is discussed below.
9.2.
Study Population Definitions
Study populations to be analyzed are defined as follow: 
Intent-to-treat (ITT): The ITT population will consist of all randomized subjects regardless of 
whether or not the subject received IP. All efficacy analyses will be conducted for the ITT 
population and will be analyzed based on randomization group.
Safety: The safety population will consist of all subjects who were randomized and received at 
least one dose of IP.  Subjects will be included in the treatment group corresponding to the IP 
they actually received.
Statistical methods to handle missing data will be described in the SAP. The SAP will describe 
any predefined rules for including/excluding any subjects with data from any analyses (eg, time 
windows, visit by visit analysis, endpoint analysis, protocol violation).
9.3.
Sample Size and Power Considerations
Based on data in the luspatercept Phase 2 (A536-04/A536-06) study the assumed targeted 
response rate for the primary endpoint is 40% in luspatercept group and 20% for the placebo 
group.  A total sample size of 300 (200 in the luspatercept group, 100 in placebo group) will 
have 90% power to detect the difference between the luspatercept group and the placebo group 
with a 2-sided alpha of 0.05 and assumed 10% drop-out rate for each treatment group.
Randomization and Stratification
Subjects will be randomized to receive luspatercept or placebo at a 2:1 ratio. Randomization will 
be accomplished by an IRT to ensure timely registration and randomization. A stratified 
randomization schedule will be implemented. Randomization will be stratified by: Geographical 
regionsa: 
∀
North America and Europe
∀
Middle East and North Africa
∀
Asia-Pacific
a See Appendix E for list of countries within each region.
9.4.
Background and Demographic Characteristics
Subjects’ age, height, weight, and baseline characteristics will be summarized using descriptive 
statistics, while gender, race and other categorical variables will be provided using frequency 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
86
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
tabulations by dose cohort.  Prior transfusion history will be summarized.  Medical history data 
will be summarized using frequency tabulations by the Medical Dictionary for Regulatory 
Activities (MedDRA) system organ class and preferred term. Beta-thalassemia diagnoses as 
well as RBC transfusion dependence will be summarized using frequency tabulations.
9.5.
Subject Disposition
Subject disposition (analysis population allocation, entered, discontinued, along with primary 
reason for discontinuation) will be summarized using frequency and percent for both treatment 
and follow-up phases.  A summary of subjects enrolled by site will be provided. Protocol 
deviations will be summarized using frequency tabulations.
9.6.
Efficacy Analysis
9.6.1.
Primary Efficacy Analysis
The efficacy analysis will be performed on the ITT population.  The primary efficacy analysis 
will be performed based on 24 weeks of data after all subjects have completed the double-blind 
24-week treatment period phase or discontinue before reaching 24 weeks of double-blind 
treatment (for this study one month equal to 4 weeks is considered). A higher response rate in the 
luspatercept over placebo and a p-value < 0.05 will confirm the superiority of luspatercept in the 
efficacy. 
The primary efficacy endpoint of this study is defined as subjects with ≥ 33% reduction from 
baseline in RBC transfusion burden with a reduction of at least 2 units from Week 13 to Week 24 
compared to the 12-week interval prior to randomization for luspatercept plus BSC versus 
placebo plus BSC. 
For the early discontinued subjects, ie, who did not complete 24 weeks of double-blinded 
treatment period, the transfusion records will still be collected up to 48 weeks. All the 
transfusion records will be used to evaluate primary and secondary endpoints. 
The first day to be used for statistical analysis will be defined as the date of the first dose. A 
transfusion received on Dose 1 Day 1 will be counted in the baseline transfusion burden.
The primary endpoint response rate is calculated using the number of responders divided by all 
subjects in the ITT population. The response rates of the subjects who randomized to 
luspatercept and the placebo will be calculated. Let 
1
P denote the true response rate in the 
luspatercept group, and 
2
P denote the true response rate in the placebo group. In the primary 
efficacy analysis, the statistical hypothesis is
2
1
2
1
0
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:
P
P
H
P
P
H
a
(
)
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calculated for luspatercept and placebo. The difference in proportions between luspatercept and 
placebo will be calculated and the Cochran Mantel-Haenszel (CMH) chi-square test would be 
performed using randomization factors as strata, corresponding 95% confidence interval (CI)
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
87
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
associated with the test will be provided. A higher response rate in the luspatercept arm over 
placebo arm with a p-value < 0.05 will infer that luspatercept is significantly superior to placebo.
9.6.2.
Secondary Efficacy Analysis
The analyses of secondary efficacy endpoints will be performed on the ITT population. The 
results will be presented by treatment groups. The statistical tests will be conducted to compare 
the treatment groups.
Gate-keeping methods will be used to control the overall Type 1 error rate for the secondary 
endpoints. After the result from the primary efficacy analysis in the ITT population shows 
statistical significance, the key secondary endpoint 1 will be tested next. The key secondary 
endpoint 2 will be tested only if the test results for both primary endpoint and the key secondary 
endpoint are significant. The key secondary endpoint 3 will be tested only if the test results for 
primary endpoint and the key secondary endpoints 1 and 2 are all significant. The testing 
procedure above will be implemented strictly in order to control the overall Type 1 error rate of 
0.05 due to multiplicity.
The secondary endpoints will be measured at 24 weeks and 48 weeks from randomization and be 
statistically tested in a sequential order at α = 0.05 level:
1. Proportion of subjects with hematological improvement, defined as ≥ 33% reduction 
from baseline in RBC transfusion burden with a reduction of at least 2 units from Week 
37 to Week 48.
2. Proportion of subjects with hematological improvement, defined as ≥ 50% reduction 
from baseline in RBC transfusion burden with a reduction of at least 2 units from Week 
13 to Week 24.
3. Proportion of subjects with hematological improvement, defined as ≥ 50% reduction 
from baseline in RBC transfusion burden with a reduction of at least 2 units from Week 
37 to Week 48.
4. Mean change in transfusion burden (RBC units) from Week 13 to Week 24.
9.6.2.1.
Proportion of Subjects with ≥ 33% Reduction from Baseline in RBC 
Transfusion Burden with a Reduction of at Least 2 Units from Week 37 to Week 
48
Subjects will be analyzed as described in Section 9.6.1 for the primary endpoint.
9.6.2.2.
Proportion of Subjects with ≥ 50% Reduction from Baseline in RBC 
Transfusion Burden with a Reduction of at Least 2 Units from Week 13 to 
Week 24
Subjects will be analyzed as described in Section 9.6.1 for the primary endpoint.
9.6.2.3.
Proportion of Subjects with ≥ 50% Reduction from Baseline in RBC 
Transfusion Burden with a Reduction of at Least 2 Units from Week 37 to Week 
48
Subjects will be analyzed as described in Section 9.6.1 for the primary endpoint
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9.6.2.3.
9.6.2.3

EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
88
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
9.6.2.4.
Mean Change in Transfusion Burden (RBC Units) from Week 13 to Week 24 
The mean change in transfusion burden (RBC units) from baseline will be analyzed using 
ANCOVA method with stratification factor and baseline transfusion burden as covariates from 
Week 13 to Week 24. Corresponding 95% CI associated with the test will be provided.
9.6.3.
Other Efficacy Analyses
Other efficacy analyses include:
1. Mean change in liver iron concentration (LIC, mg/g dw) by MRI 
2. Mean change in mean daily dose of iron chelation therapy (ICT)
3. Change in serum ferritin
4. Mean change in total hip and lumbar spine bone mineral density (BMD) by DXA
5. Mean change in myocardial iron by MRI
6. Mean change in Quality of Life using TranQoL and SF36
7. Healthcare resource utilization 
8. Proportion of subjects who are transfusion independent for ≥ 8 weeks during treatment 
9. Duration of reduction in transfusion burden 
10. Duration of transfusion independence 
11. Time to erythroid response
12. Post-baseline transfusion events frequency versus placebo
In general, descriptive statistics will be provided and statistical tests will be applied if 
appropriate. 
Kaplan-Meier methods will be used to analyze time to event secondary variables. All other 
secondary efficacy variables will be analyzed descriptively. Counts and percentages will be used 
to describe categorical secondary variables.
The statistical assumption for ANCOVA method will be validated, and log transformation may 
be applied as appropriate.
9.6.3.1.
Mean Change in Liver Iron Concentration (LIC)
There are 3 scheduled LIC measurements for each subject: baseline, 24 weeks and 48 weeks. For 
subjects who discontinued before 48 weeks, LIC may also be measured at the time of 
discontinuation. The 48-week LIC change from baseline will be analyzed using an analysis of 
covariance (ANCOVA) with the randomization stratification factors and baseline LIC as 
covariates. For any subject, if the 48-week LIC measurement is not available, the last LIC 
measurement before 48 week will be used instead.
9.6.3.2.
Mean Change in Mean Daily Dose of Iron Chelation Therapy (ICT)
For a subject, the baseline mean daily dose will be calculated using ICT dosage during the 12
weeks prior to first study drug treatment. The post baseline mean daily dose will be calculated 
using ICT dosage during the last 12 weeks of the 48 weeks double-blind Treatment Period or last 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
89
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
12 weeks of study treatment if discontinue early. The change in daily dose for each subject is 
calculated as the difference of post-baseline mean daily dose and baseline mean daily dose. 
ANCOVA will be used to compare the treatment difference between groups, with the 
stratification factor and baseline ICT value as covariates.
9.6.3.3.
Mean Change in Serum Ferritin Level
For a subject, the baseline mean serum ferritin will be calculated during the 12 weeks prior to 
first study drug treatment. The post baseline mean serum ferritin will be calculated during the
last 12 weeks of the 48 weeks double-blind Treatment Period or last 12 weeks of study treatment 
if discontinue early. The change is calculated as the difference of post-baseline mean serum 
ferritin and baseline mean serum ferritin. ANCOVA will be used to compare the treatment 
difference between groups, with the stratification factors and baseline serum ferritin value as
covariates.
9.6.3.4.
Bone Mineral Density Assessed by DXA Scan
For bone mineral density, the lumbar spine and total hip will be measured at baseline and at 48 
weeks. Change from baseline lumbar spine score will be analyzed using ANCOVA method with 
randomization factor and baseline lumbar spine score as covariates. Change from baseline total 
hip score will be analyzed using ANCOVA method with randomization factors and baseline total 
hip score as covariates. The analysis will be done on the population that have at least 2 
measurements.
9.6.3.5.
Mean Change in Myocardial Iron by MRI
There are 2 scheduled myocardial iron measurements for each subject: baseline and 48 weeks. 
For subjects who discontinued before 48 weeks, myocardial iron will be measured at the time of 
discontinuation. The 48-week myocardial iron change from baseline will be analyzed using an 
analysis of covariance (ANCOVA) with the randomization stratification factors and baseline 
myocardial iron as covariates. For any subject, if the 48-week myocardial iron measurement is 
not available, the last myocardial iron measurement before 48 week will be used instead.
9.6.3.6.
Change in Quality of Life using TranQol and SF-36 
SF-36: The SF-36 Version 2.0 is a self-administered instrument consisting of 8 multi-item scales 
that assess 8 health domains: Physical functioning, Role-Physical, Bodily Pain, General Health, 
Vitality, Social functioning, Role-Emotional, and Mental Health. Two overall summary scores 
(Physical Component and Mental Component) can also be obtained. Summary statistics (N, 
mean, median, standard deviation [SD], range, skewness, kurtosis) for the Physical functioning, 
Role – Physical, General Health, Vitality, Social Functioning domain scores, and the Physical 
Component summary score, as well as change from baseline in these scores, will be assessed at 
Week 12, 24, 36 and 48 and then every 12 weeks during the Long-term Treatment 
Period. Summary statistics will be calculated for the total sample and for each treatment group.
Scoring for the SF-36 and methods to address missing values within an assessment (ie, scores 
missing for individual items) will follow directions provided by the instrument developers.
Mixed-model analyses will examine the effect of luspatercept treatment on change in the SF-36
domain scores from baseline to 48 weeks. The models will include the SF-36 change scores from 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
90
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
baseline as the outcome (in separate analyses), and time, treatment group assignment, 
stratification factors, and a time-by-treatment group assignment term in the model. The mixed-
model analysis allows for subjects to contribute different numbers of data points to analysis. 
Therefore, there will be no score estimation for missing assessments. We will assume an 
unstructured correlation structure for the analyses of these data. The test of the significance of 
the interaction terms in these models will provide a test of differences across time for the two 
treatment arms. If time-by-treatment group assignment term is not significant, we will exclude 
the interaction term from the model, and the final model will include the SF-36 change scores 
from baseline as the outcome, and time, treatment group assignment, and stratification factor. In 
this model, the significance of overall treatment effect will be tested by the treatment group 
assignment term.
TranQol: Chronically transfused patients with thalassemia major have a unique set of concerns 
that are not adequately addressed by generic quality of life tools. The TranQol is a tool specific 
to this population. The TranQol is a new disease-specific quality of life instrument developed for 
adult Beta-thalassemia patients. 
Summary statistics (N, mean, median, SD, range, skewness, kurtosis) for scores from the pre-
specified domains of emotional and the School / Career domains and the total score will be 
calculated at each administration time point (baseline, weeks 12, 24, 36 and 48 and then every 12 
weeks during the Long-term Treatment Period) for the total sample and each treatment group. 
Summary statistics will also be calculated for change from baseline in each score at each 
administration time point for the total sample and each treatment group. Scoring for the TranQoL 
and methods to address missing values within an assessment (ie, scores missing for individual 
items) will follow directions provided by the instrument developers.
Mixed-model analyses will examine the effect of luspatercept treatment on change in the 
TranQoL total score and domain scores from baseline to 48 weeks. The models will include the 
TranQoL change scores from baseline as the outcome (in separate analyses), and time, treatment 
group assignment, stratification factors, and a time-by-treatment group assignment term in the 
model. The mixed-model analysis allows for subjects to contribute different numbers of data 
points to analysis. Therefore, there will be no score estimation for missing assessments. We will 
assume an exchangeable correlation structure for the analyses of these data. The test of the 
significance of the interaction terms in these models will provide a test of differences across time 
for the two treatment arms. If time-by-treatment group assignment term is not significant, we 
will exclude the interaction term from the model, and the final model will include the TranQoL 
change scores from baseline as the outcome, and time, treatment group assignment, and 
stratification factor. In this model, the significance of overall treatment effect will be tested by 
the treatment group assignment term.
9.6.3.7.
Healthcare Resource Utilization
Characterization of medical resource utilization among subjects treated with luspatercept plus 
BSC as compared to subjects receiving placebo plus BSC treatment. Health care resource 
utilization includes an aggregation of hospitalizations, prior concomitant therapies and surgeries, 
as well as RBC transfusion utilization. Details of the analysis will be provided in the SAP.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
91
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
9.6.3.8.
Duration of Transfusion Burden Reduction 
The duration of the response will be calculated for each subject who achieves a response. The 
general algorithms used to calculate the duration of response are as follows:
First Day of Response = the first day of showing response. Last Day of Response = last day of 
showing response.  Date of Last Assessment = either the last visit date for subjects still on drug 
or the date of discontinuation for subjects who discontinued from the treatment.
The duration of response will be calculated as follows, depending on whether or not the response 
ends before the Date of Last Assessment:
∀
For subjects who response does not continue to the end of the treatment period, the 
duration of response is not censored, and is calculated as
Response Duration = Last Day of Response – First Day of Response +1.
∀
For subjects who continue to respond at the end of the treatment period, the end day 
of the response is censored and duration of the response is calculated as
Response duration = Date of Last Assessment – First Day of Response +1
The longest duration will be used if there are multiple intervals of transfusion burden 
reduction, and the sum of the durations will be summarized if applicable.
Only subjects who achieve response will be included in the analysis. For each 
treatment group, the Kaplan–Meier method will be used to estimate the median 
duration of response and to calculate the 95% CI for the median duration of response.  
The Kaplan-Meier plots of the time to end of response will also be provided.
9.6.3.9.
Time to Response
The time to the first response will be calculated for subjects who achieved a response as follows:
Time to Response = First Day of Response – Date of First Study Drug +1 
The analysis of time to response will be based on the data collected during the double-blind 
phase.  The time to the first response will be summarized using descriptive statistics by treatment 
groups.
9.6.3.10.
Transfusion Independence 
Transfusion independence is defined as the absence of any transfusion during any consecutive 
“rolling” 8-week time interval within the treatment period, ie, Days 1 to 56, Days 2 to 57 and so 
on.  Subjects discontinued from double-blind treatment for lack of therapeutic effect or with less 
than 56 days of assessment during the double-blind treatment period will be counted as non-
responders. The number and percent of subjects who achieve transfusion independence (defined 
as at least 8 weeks transfusion-free) will be compared between the two treatment groups.  The 
Cochran Mantel-Haenszel (CMH) test with stratification factor as strata would be performed 
with randomization factors as strata, corresponding 95% CI associated with the test will be 
provided.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
92
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
9.6.3.11.
Postbaseline Transfusion Events Frequency Versus Placebo
The postbaseline transfusion event frequency will be analyzed using negative binomial
regression with randomization stratification factor and baseline transfusion frequency in the 
regression model.
Annualized mean change from baseline number of transfusion events will be summarized by 
treatment groups
9.7.
Safety Analysis
All safety analyses will be performed on the safety population. Full details will be included in 
the SAP. Planned data presentations and analyses include the following:
∀
Adverse events will be coded using MedDRA. Adverse event listings will include the 
verbatim term and the MedDRA preferred term.  Treatment-emergent adverse events 
will be summarized by worst severity grade, system organ class, and preferred term.  
Treatment-emergent adverse events leading to death or to discontinuation from 
treatment, TEAEs classified as NCI CTCAE (version 4.0) all grades and grade 3/4
TEAEs, related to investigational product, and serious TEAEs will be summarized 
separately.
∀
Clinical laboratory results will be summarized descriptively by treatment group. 
Clinically significant hematologic and non-hematologic laboratory abnormalities will 
be listed and summarized according to the NCI CTCAE by treatment group.
∀
Vital sign measurements, including body weight, will be listed for each subject at 
each visit. Descriptive statistics for vital signs, both observed values and changes 
from baseline, will be summarized by treatment group.
Cross tabulations will be provided to summarize frequencies of abnormalities.  
Descriptive statistics will be provided for vital sign and body weight data.  
By-subject listings will be provided for all relevant safety data.  Graphical displays and figures 
will be provided where useful to assist in the interpretation of results.
9.8.
Interim Analysis
No Interim Analysis is planned.
9.9.
Timing of Analyses
9.9.1.
Final Analysis 
9.9.1.1.
Clinical Study Report for Marketing Authorization Application 
A clinical study report (CSR) for a marketing authorization application (MAA) will include 
safety and efficacy parameters at the time of the final analysis when all subjects completed 48 
weeks of a double-blind Treatment Period or discontinued before reaching 48 weeks. With this 
cut-off date and upon the data base lock the study will be unblinded.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
93
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
The efficacy analyses included in the CSR for MAA will be conducted on the primary endpoint, 
secondary endpoints, and safety endpoints. 
9.9.1.2.
Final Clinical Study Report 
The final CSR will include efficacy and safety data at the time of the End of the Trial.(ie, when 
all subjects initially assigned to luspatercept in the double-blind Treatment Period have 
completed the total treatment duration of 5 years from the subject’s Dose 1 Day 1 in the 
treatment period of this ACE-536-B-THAL-001 study or have discontinued earlier and 
completed the 156-week Post-treatment Follow-up Period, whichever occurred later.)
The final efficacy analyses will be conducted on primary endpoint, secondary endpoints and 
safety endpoints. 
9.10.
Other Topics
 
 
 
 
 
 
 
 
  
9.10.2.
Data Monitoring Committee (DMC)
The independent DMC will be comprised of expert(s) in β-thalassemia not involved in ACE-
536-B-THAL-001 Protocol, an Independent Cardiologist, an Independent Statistician, and may 
include additional ad hoc members. Representatives of the Sponsor will be attending the blinded 
part of the DMC meetings. The Sponsor will not have access to the unblinded data.
During the course of the study, the DMC will review the unblinded safety data regularly as well 
as safety and efficacy data in accordance with the guidelines for the preplanned analyses.  An 
independent third party will prepare the reports of aggregate data summaries and individual 
subject data listings, as appropriate, to the DMC members for each scheduled meeting.
The DMC responsibilities, authorities, and procedures will be detailed in the DMC charter, 
which will be endorsed by the DMC prior to the first data review meeting.
Operational details for the DMC will be detailed in the DMC charter.
9.10.3.
Steering Committee 
A Steering Committee will be established by charter for this study.  The Steering Committee will
be comprised of Study Investigators, Sponsor representatives, and may include additional ad hoc 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
94
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
members.  The Steering Committee will review blinded data. The Steering Committee will serve 
in an advisory capacity to the Sponsor.  The Steering Committee will advise and recommend to 
the Sponsor:
∀
Changes to the protocol or conduct of the study based upon emerging clinical or 
scientific data from this and/or other studies.
∀
Procedures to ensure the safety of subjects and integrity of study data.
∀
Procedures to meet the overall goals and objectives of the study.
The Steering Committee responsibilities, authorities, and procedures will be detailed in the 
Steering Committee charter, which will be endorsed by the Steering Committee prior to the first 
data review meeting.
Operational details for the Steering Committee will be detailed in a separate Steering Committee
charter.
Note: The Steering Committee is separate from the DMC.
 
 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
95
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
10.
ADVERSE EVENTS
10.1.
Monitoring, Recording and Reporting of Adverse Events
An AE is any noxious, unintended, or untoward medical occurrence that may appear or worsen 
in a subject during the course of a study. It may be a new intercurrent illness, a worsening 
concomitant illness, an injury, or any concomitant impairment of the subject’s health, including 
laboratory test values (as specified by the criteria in Section 10.3), regardless of etiology. Any 
worsening (ie, any clinically significant adverse change in the frequency or intensity of a pre-
existing condition) should be considered an AE.  A diagnosis or syndrome should be recorded on 
the AE page of the eCRF rather than the individual signs or symptoms of the diagnosis or 
syndrome. 
Abuse, withdrawal, sensitivity or toxicity to an investigational product should be reported as an 
AE. Overdose, accidental or intentional, whether or not it is associated with an AE should be 
reported on the overdose eCRF. (See Section 7.2.1.3 for the definition of overdose.) Any 
sequela of an accidental or intentional overdose of an investigational product should be reported 
as an AE on the AE eCRF. If the sequela of an overdose is a serious adverse event (SAE), then 
the sequela must be reported on an SAE report form and on the AE eCRF. The overdose 
resulting in the SAE should be identified as the cause of the event on the SAE report form and 
eCRF but should not be reported as an SAE itself.
In the event of overdose, the subject should be monitored as appropriate and should receive 
supportive measures as necessary. There is no known specific antidote for luspatercept 
overdose. Actual treatment should depend on the severity of the clinical situation and the 
judgment and experience of the treating physician.
All subjects will be monitored for AEs during the study.  Assessments may include monitoring 
of any or all of the following parameters:  the subject’s clinical symptoms, laboratory, 
pathological, radiological or surgical findings, physical examination findings, or findings from 
other tests and/or procedures.
All AEs regardless of causality will be recorded by the Investigator from the time the subject 
signs informed consent until 9 weeks after the last dose of IP as well as those SAEs made known 
to the Investigator at any time thereafter that are suspected of being related to IP. In addition, 
AEs that are suspected to be related to the IP as well as new malignancies or pre-malignancies 
regardless of causality (see Section 10.5.2) will be recorded by the Investigator until 156 weeks 
after the last dose of IP.  Information will be collected as described in the Table of Events,
Table 3 and Section 6.6. AEs and SAEs will be recorded on the AE page of the eCRF and in the 
subject’s source documents.  All SAEs must be reported to Celgene Drug Safety within 24 hours
of the Investigator’s knowledge of the event by facsimile, or other appropriate method, using the 
SAE Report Form, or approved equivalent form.  
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
96
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
10.2.
Evaluation of Adverse Events
A qualified Investigator will evaluate all adverse events as to: 
10.2.1.
Seriousness
An SAE is any AE occurring at any dose that:
∀
Results in death;
∀
Is life-threatening (ie, in the opinion of the Investigator, the subject is at immediate 
risk of death from the AE);
∀
Requires inpatient hospitalization or prolongation of existing hospitalization
(hospitalization is defined as an inpatient admission, regardless of length of stay);
∀
Results in persistent or significant disability/incapacity (a substantial disruption of the 
subject’s ability to conduct normal life functions);
∀
Is a congenital anomaly/birth defect;
∀
Constitutes an important medical event.
Important medical events are defined as those occurrences that may not be immediately life-
threatening or result in death, hospitalization, or disability, but may jeopardize the subject or 
require medical or surgical intervention to prevent one of the other outcomes listed above.  
Medical and scientific judgment should be exercised in deciding whether such an AE should be 
considered serious.
Events not considered to be SAEs are hospitalizations for:
∀
a standard procedure for protocol therapy administration.  However, hospitalization or 
prolonged hospitalization for a complication of therapy administration will be 
reported as an SAE.
∀
routine treatment or monitoring of the studied indication not associated with any 
deterioration in condition.
∀
the administration of blood or platelet transfusion as routine treatment of studied 
indication.  However, hospitalization or prolonged hospitalization for a complication 
of such transfusion remains a reportable SAE.
∀
a procedure for protocol/disease-related investigations (eg, surgery, scans, endoscopy, 
sampling for laboratory tests, bone marrow sampling).  However, hospitalization or 
prolonged hospitalization for a complication of such procedures remains a reportable 
SAE.
∀
hospitalization or prolongation of hospitalization for technical, practical, or social 
reasons, in absence of an AE.
∀
a procedure that is planned (ie, planned prior to start of treatment on study); must be 
documented in the source document and the eCRF.  Hospitalization or prolonged 
hospitalization for a complication remains a reportable SAE.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
97
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
∀
an elective treatment of or an elective procedure for a pre-existing condition,
unrelated to the studied indication, that has not worsened from baseline. 
∀
emergency outpatient treatment or observation that does not result in admission, 
unless fulfilling other seriousness criteria above.
If an AE is considered serious, both the AE page/screen of the eCRF and the SAE Report Form 
must be completed.
For each SAE, the Investigator will provide information on severity, start and stop dates, 
relationship to the IP, action taken regarding the IP, and outcome.
10.2.2.
Severity/ Intensity
For both AEs and SAEs, the Investigator must assess the severity/ intensity of the event. 
The severity/intensity of AEs will be graded based upon the subject’s symptoms according to the 
current active minor version of the Common Terminology Criteria for Adverse Events (CTCAE, 
Version 4.0); 
http://ctep.cancer.gov/protocolDevelopment/electronic_applications/ctc.htm#ctc_40
AEs that are not defined in CTCAE should be evaluated for severity/intensity according to the 
following scale:
∀
Grade 1 = Mild – transient or mild discomfort; no limitation in activity; no medical 
intervention/therapy required
∀
Grade 2 = Moderate – mild to moderate limitation in activity, some assistance may be 
needed; no or minimal medical intervention/therapy required
∀
Grade 3 = Severe – marked limitation in activity, some assistance usually required; 
medical intervention/therapy required, hospitalization is possible
∀
Grade 4 = Life-threatening – extreme limitation in activity, significant assistance 
required; significant medical intervention/therapy required, hospitalization or hospice 
care probable
∀
Grade 5 = Death - the event results in death
The term “severe” is often used to describe the intensity of a specific event (as in mild, moderate 
or severe myocardial infarction); the event itself, however, may be of relatively minor medical 
significance (such as severe headache).  This criterion is not the same as “serious” which is 
based on subject/event outcome or action criteria associated with events that pose a threat to a 
subject’s life or functioning.  
Seriousness, not severity, serves as a guide for defining regulatory obligations.
10.2.3.
Causality
The Investigator must determine the relationship between the administration of the IP and the 
occurrence of an AE/SAE as Not Suspected or Suspected as defined below:
Not suspected:
a causal relationship of the adverse event to IP administration is 
unlikely or remote, or other medications, therapeutic 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
98
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
interventions, or underlying conditions provide a sufficient 
explanation for the observed event.
Suspected:
there is a reasonable possibility that the administration of IP 
caused the adverse event.  ‘Reasonable possibility’ means there 
is evidence to suggest a causal relationship between the IP and 
the adverse event.
Causality should be assessed and provided for every AE/SAE based on currently available 
information.  Causality is to be reassessed and provided as additional information becomes 
available.
If an event is assessed as suspected of being related to a comparator, ancillary or additional IP
that has not been manufactured or provided by Celgene, please provide the name of the 
manufacturer when reporting the event.
10.2.4.
Duration
For both AEs and SAEs, the Investigator will provide a record of the start and stop dates of the 
event.
10.2.5.
Action Taken
The Investigator will report the action taken with IP as a result of an AE or SAE, as applicable 
(eg, discontinuation, interruption, or dose reduction of IP, as appropriate) and report if 
concomitant and/or additional treatments were given for the event. 
10.2.6.
Outcome
The Investigator will report the outcome of the event for both AEs and SAEs.
All SAEs that have not resolved upon discontinuation of the subject’s participation in the study 
must be followed until recovered (returned to baseline), recovered with sequelae, or death (due to 
the SAE).
10.3.
Abnormal Laboratory Values
An abnormal laboratory value is considered to be an AE if the abnormality:
∀
results in discontinuation from the study;
∀
requires treatment, modification/ interruption of IP dose, or any other therapeutic 
intervention; or
∀
is judged to be of significant clinical importance, eg, one that indicates a new disease 
process and/or organ toxicity, or is an exacerbation or worsening of an existing 
condition.
Regardless of severity grade, only laboratory abnormalities that fulfill a seriousness criterion 
need to be documented as a serious adverse event.
If a laboratory abnormality is one component of a diagnosis or syndrome, then only the diagnosis 
or syndrome should be recorded on the AE page/screen of the eCRF.  If the abnormality was not 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
99
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
a part of a diagnosis or syndrome, then the laboratory abnormality should be recorded as the AE.
If possible, the laboratory abnormality should be recorded as a medical term and not simply as an 
abnormal laboratory result (eg, record thrombocytopenia rather than decreased platelets).
10.4.
Pregnancy
All pregnancies or suspected pregnancies occurring in either a female subject of childbearing 
potential or partner of childbearing potential of a male subject are immediately reportable events.
10.4.1.
Females of Childbearing Potential
Females of childbearing potential will be advised to avoid becoming pregnant during the study 
and for 12 weeks after the last dose of IP. Pregnancies and suspected pregnancies (including 
elevated βhCG or positive pregnancy test in a female subject of childbearing potential regardless 
of disease state) occurring while the subject is on IP, or within 12 weeks of the subject’s last dose 
of IP, are considered immediately reportable events.  Investigational product is to be 
discontinued immediately. The pregnancy, suspected pregnancy, or positive pregnancy test must 
be reported to Celgene Drug Safety immediately by email, phone or facsimile, or other 
appropriate method, using the Pregnancy Initial Report Form, or approved equivalent form.  
The female subject may be referred to an obstetrician-gynecologist or another appropriate 
healthcare professional for further evaluation.
The Investigator will follow the female subject until completion of the pregnancy, and must 
notify Celgene Drug Safety immediately about the outcome of the pregnancy (either normal or 
abnormal outcome) using the Pregnancy Follow-up Report Form, or approved equivalent form.
If the outcome of the pregnancy was abnormal (eg, spontaneous abortion), the Investigator 
should report the abnormal outcome as an AE. If the abnormal outcome meets any of the serious 
criteria, it must be reported as an SAE to Celgene Drug Safety by facsimile, or other appropriate 
method, within 24 hours of the Investigator’s knowledge of the event using the SAE Report 
Form, or approved equivalent form.
All neonatal deaths that occur within 28 days of birth should be reported, without regard to 
causality, as SAEs.  In addition, any infant death after 28 days that the Investigator suspects is 
related to the in utero exposure to the IP should also be reported to Celgene Drug Safety by 
facsimile, or other appropriate method, within 24 hours of the Investigator’s knowledge of the 
event using the SAE Report Form, or approved equivalent form.
10.4.2.
Male Subjects
If a female partner of a male subject taking IP becomes pregnant, the male subject taking IP 
should notify the Investigator, and the pregnant female partner should be advised to call their 
healthcare provider immediately. 
Males will be advised to use a latex condom during any sexual contact with a FCBP prior to 
starting investigational product and continue for 12 weeks following the last dose of IP, even if 
he has undergone a successful vasectomy.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
100
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
10.5.
Reporting of Serious Adverse Events
Any AE that meets any criterion for an SAE requires the completion of an SAE Report Form in 
addition to being recorded on the AE page/screen of the eCRF.  All SAEs must be reported to 
Celgene Drug Safety within 24 hours of the Investigator’s knowledge of the event by facsimile, 
or other appropriate method (eg, via email), using the SAE Report Form, or approved equivalent 
form.  This instruction pertains to initial SAE reports as well as any follow-up reports.
The Investigator is required to ensure that the data on these forms is accurate and consistent.  
This requirement applies to all SAEs (regardless of relationship to IP) that occur during the study 
(from the time the subject signs informed consent until 9 weeks after the last dose of IP) or any 
SAE made known to the Investigator at any time thereafter that are suspected of being related to 
IP until the End of Study.  Serious adverse events occurring prior to treatment (after signing the 
ICF) will be captured.
The SAE report should provide a detailed description of the SAE and include a concise summary
of hospital records and other relevant documents.  If a subject died and an autopsy has been 
performed, copies of the autopsy report and death certificate are to be sent to Celgene Drug 
Safety as soon as these become available.  Any follow-up data should be detailed in a subsequent 
SAE Report Form, or approved equivalent form, and sent to Celgene Drug Safety.  
Where required by local legislation, the Investigator is responsible for informing the Institutional 
Review Board/Ethics Committee (IRB/EC) of the SAE and providing them with all relevant 
initial and follow-up information about the event. The Investigator must keep copies of all SAE 
information on file including correspondence with Celgene and the IRB/EC.
10.5.1.
Safety Queries
Queries pertaining to SAEs will be communicated from Celgene Drug Safety to the site via 
facsimile or electronic mail.  The response time is expected to be no more than five (5) business 
days.  Urgent queries (eg, missing causality assessment) may be handled by phone.
10.5.2.
Malignancy and Pre-malignancy Reporting
The occurrence of a new malignancy or pre-malignant lesion will be monitored as an event of 
interest and should be included as part of the assessment of adverse events throughout the course 
of the study. Investigators are to report the development of any new malignancy or pre-
malignant lesion as a serious adverse event, regardless of causal relationship to IP, occurring at 
any time for the duration of the study, from the time of signing the ICF up to and including 156
weeks of follow-up.
Events of new malignancy or pre-malignant lesions (excluding benign tumors or benign 
neoplasia) are to be reported to Celgene Drug Safety within 24 hours of the Investigator’s 
knowledge of the event by facsimile, or other appropriate method, using the SAE Report Form, 
or approved equivalent form and must be considered an “Important Medical Event” even if no 
other serious criteria apply; these events must also be documented in the appropriate page(s) of 
the CRF and subject’s source documents. Documentation of the diagnosed malignancy must be 
provided at the time of reporting as a serious adverse event (eg, any confirmatory histology or 
cytology results, x-rays, CT scans, etc.).
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
101
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Malignancies or cancerous tumors are lesions capable of invading into adjacent tissues, and may 
be capable of spreading to distant tissues. A benign tumor has none of those properties.
Malignancy or cancer is characterized by anaplasia, invasiveness, and metastasis.
Pre-malignant or precancerous lesions refer to a state of disordered morphology of cells that is 
associated with an increased risk of cancer. If left untreated, these conditions may lead to cancer. 
Such conditions are usually either dysplasia or benign neoplasia (and the dividing line between 
those is sometimes blurry). Sometimes the term "precancer" is used to describe carcinoma in 
situ, which is a noninvasive cancer that has not progressed to an aggressive, invasive stage. Not 
all carcinoma in situ will progress to invasive disease.
Pre-malignant lesions are morphologically atypical tissue which appears abnormal under 
microscopic examination, and in which cancer is more likely to occur than in its apparently 
normal counterpart.
10.6.
Expedited Reporting of Adverse Events
For the purpose of regulatory reporting, Celgene Drug Safety will determine the expectedness of 
events suspected of being related to luspatercept based on the Investigator Brochure.
In the United States, all suspected unexpected serious adverse reactions (SUSARs) will be 
reported in an expedited manner in accordance with 21 CFR 312.32.
For countries within the European Economic Area (EEA), Celgene or its authorized 
representative will report in an expedited manner to Regulatory Authorities and Ethics 
Committees concerned, SUSARs in accordance with Directive 2001/20/EC and the Detailed 
Guidance on collection, verification and presentation of adverse reaction reports arising from 
clinical trials on investigational products for human use (ENTR/CT3) and also in accordance 
with country-specific requirements.  
In addition, any report of hematologic malignancy regardless of causality in the luspatercept arm, 
will be reported to the regulatory authorities in an expedited manner, if requested. 
Celgene or its authorized representative shall notify the Investigator of the following 
information:
∀
Any AE suspected of being related to the use of IP in this study or in other studies 
that is both serious and unexpected (ie, SUSAR);
∀
Any finding from tests in laboratory animals that suggests a significant risk for 
human subjects including reports of mutagenicity, teratogenicity, or carcinogenicity.
Where required by local legislation, the Investigator shall notify his/her IRB/EC promptly of 
these new serious and unexpected AE(s) or significant risks to subjects.
The Investigator must keep copies of all pertinent safety information on file including 
correspondence with Celgene and the IRB/EC.  (See Section 14.3 for record retention 
information).
Celgene Drug Safety Contact Information:
For Celgene Drug Safety contact information, please refer to the Serious Adverse Event Report 
Form Completion Guidelines or to the Pregnancy Report Form Completion Guidelines.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
102
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
11.
DISCONTINUATIONS
11.1.
Treatment Discontinuation
Subjects will have a treatment discontinuation visit at the time of study drug discontinuation.  All 
subjects who received at least one dose of the study drug will be followed for 156 weeks 
post-treatment. 
The following events are considered sufficient reasons for discontinuing a subject from the 
investigational product(s):
∀
Adverse Event(s):
&
Any serious AE assessed as related to luspatercept
&
Any AE ≥ Grade 3 assessed to be related to luspatercept if the event causes a 
treatment delay of 15 weeks or longer from the prior administered dose, including 
hypersensitivity to luspatercept.
&
If a subject experiences > 2 Dose Reductions due to related AE
∀
Any new malignancy
∀
Withdrawal of consent - An indication that a study participant has removed itself 
from the study treatment 
∀
Death 
∀
Lost to follow-up - the loss or lack of continuation of a subject to follow-up
∀
Pregnancy
∀
If dose is delayed for more than 15 weeks or longer from the prior dose administered
dose due to AE, including case of elective surgery/hospitalization
∀
Other: Different than the one(s) previously specified or mentioned
The reason for discontinuation of treatment should be recorded in the eCRF and in the source 
documents.
The decision to discontinue a subject from treatment remains the responsibility of the treating 
physician, which will not be delayed or refused by the Sponsor.  However, prior to discontinuing 
a subject, the Investigator may contact the Medical Monitor and forward appropriate supporting 
documents for review and discussion.
11.2.
End of Study
The following events are considered sufficient reasons for discontinuing a subject from the 
study:
∀
Screen failure
∀
Completed study per protocol
∀
Withdrawal of consent - An indication that a study participant has removed itself 
from the study
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
103
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
∀
Death 
∀
Lost to follow-up - The loss or lack of continuation of a subject to follow-up
∀
Other: Different than the one(s) previously specified or mentioned
The following events may be considered sufficient reasons for discontinuing a subject from the 
study:
∀
Adverse events(s) - Any untoward medical occurrence in a subject or clinical 
investigation subject administered a pharmaceutical product and which does not 
necessarily have a causal relationship with this treatment. An adverse event (AE) can 
therefore be any unintended sign (including an abnormal laboratory finding), 
symptom, or disease temporally associated with the use of a medicinal 
(investigational) product, whether or not related to the medicinal (investigational) 
product. NOTE: For further information, see the ICH Guideline for Clinical Safety 
Data Management: Definitions and Standards for Expedited Reporting. [Modified 
from ICH E2A] Synonyms: side effect, adverse experience. See also serious adverse 
event, serious adverse experience
The reason for End of Study should be recorded in the eCRF and in the source documents.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
104
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
12.
EMERGENCY PROCEDURES
12.1.
Emergency Contact
In emergency situations, the Investigator should contact the responsible Clinical Research
Physician/Medical Monitor or designee by telephone at the number(s) listed on the Emergency 
Contact Information page of the protocol (after title page).
In the unlikely event that the Clinical Research Physician/Medical Monitor or designee cannot be 
reached, please contact the global Emergency Call Center by telephone at the number listed on 
the Emergency Contact Information page of the protocol (after title page). This global 
Emergency Call Center is available 24 hours a day and 7 days a week. The representatives are 
responsible for obtaining your call-back information and contacting the on-call Celgene/contract 
research organization Medical Monitor, who will then contact you promptly.
Note: The back-up 24-hour global emergency contact call center should only be used if you are 
not able to reach the Clinical Research Physician(s) or Medical Monitor or designee for 
emergency calls. 
12.2.
Emergency Identification of Investigational Products (Emergency 
Unblinding)
The blind must not be broken during the course of the study unless in the opinion of the 
Investigator, it is absolutely necessary to safely treat the subject.  If it is medically imperative to 
know what IP the subject is receiving, IP should be temporarily discontinued if, in the opinion of 
the Investigator, continuing IP can negatively affect the outcome of the subject’s treatment.
The decision to break the blind in emergency situations remains the responsibility of the treating 
physician, which will not be delayed or refused by the Sponsor.  However, the Investigator may 
contact the Medical Monitor prior to breaking the blind to discuss unblinding, mainly in the 
interest of the subject. 
The Investigator should ensure that the code is broken only in accordance with the protocol. The 
Investigator should promptly notify the Medical Monitor of the emergency unblinding and the 
reason for breaking the blind, which should be clearly documented by the Investigator in the 
subject’s source documentation.
Emergency unblinding should only be performed by the Investigator through the IRT by using an 
emergency unblinding personal identification number (PIN), and the Investigator should call IRT
for unblended dose information.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
105
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
13.
REGULATORY CONSIDERATIONS
13.1.
Good Clinical Practice
The procedures set out in this study protocol pertaining to the conduct, evaluation, and 
documentation of this study are designed to ensure that Celgene, its authorized representative,
and Investigator abide by Good Clinical Practice (GCP), as described in International 
Conference on Harmonisation (ICH) Guideline E6 and in accordance with the general ethical 
principles outlined in the Declaration of Helsinki. The study will receive approval from an 
IRB/EC prior to commencement. The Investigator will conduct all aspects of this study in 
accordance with applicable national, state, and local laws of the pertinent regulatory authorities.
13.2.
Investigator Responsibilities
Investigator responsibilities are set out in the ICH Guideline for Good Clinical Practice and in 
the local regulations.  Celgene staff or an authorized representative will evaluate and approve all 
Investigators who in turn will select their staff.
The Investigator should ensure that all persons assisting with the study are adequately informed 
about the protocol, amendments, study treatments, as well as study-related duties and functions, 
including obligations of confidentiality of Celgene information. The Investigator should maintain 
a list of Sub-investigators and other appropriately qualified persons to whom he or she has 
delegated significant study-related duties.
The Investigator is responsible for keeping a record of all subjects who sign an informed consent 
form (ICF) and are screened for entry into the study.  Subjects who fail screening must have the 
reason(s) recorded in the subject’s source documents.
The Investigator, or a designated member of the Investigator’s staff, must be available during 
monitoring visits to review data, resolve queries and allow direct access to subject records (eg, 
medical records, office charts, hospital charts, and study-related charts) for source data 
verification.  The Investigator must ensure timely and accurate completion of eCRFs and queries.
The information contained in the protocol and amendments (with the exception of the 
information provided by Celgene on public registry websites) is considered Celgene confidential 
information.  Only information that is previously disclosed by Celgene on a public registry 
website may be freely disclosed by the Investigator or its institution, or as outlined in the Clinical 
Trial Agreement.  Celgene protocol, amendment and IB information is not to be made publicly 
available (for example on the Investigator’s or their institution’s website) without express written 
approval from Celgene.  Information proposed for posting on the Investigator’s or their 
institution’s website must be submitted to Celgene for review and approval, providing at least 5 
business days for review.
At the time results of this study are made available to the public, Celgene will provide 
Investigators with a summary of the results that is written for the lay person. The Investigator is 
responsible for sharing these results with the subject and/or their caregiver as agreed by the 
subject.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
106
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
13.3.
Subject Information and Informed Consent
The Investigator must obtain informed consent of a subject and/or a subject’s legal representative 
prior to any study related procedures.
Documentation that informed consent occurred prior to the study subject’s entry into the study 
and of the informed consent process should be recorded in the study subject’s source documents 
including the date.  The original ICF signed and dated by the study subject and by the person 
consenting the study subject prior to the study subject’s entry into the study, must be maintained 
in the Investigator’s study files and a copy given to the study subject.  In addition, if a protocol is 
amended and it impacts on the content of the informed consent, the ICF must be revised.  Study 
subjects participating in the study when the amended protocol is implemented must be re-
consented with the revised version of the ICF.  The revised ICF signed and dated by the study 
subject and by the person consenting the study subject must be maintained in the Investigator’s 
study files and a copy given to the study subject.
13.4.
Confidentiality
Celgene affirms the subject's right to protection against invasion of privacy and to be in 
compliance with ICH and other local regulations (whichever is most stringent). Celgene requires 
the Investigator to permit Celgene's representatives and, when necessary, representatives from 
regulatory authorities, to review and/or copy any medical records relevant to the study in 
accordance with local laws.
Should direct access to medical records require a waiver or authorization separate from the 
subject’s signed ICF, it is the responsibility of the Investigator to obtain such permission in 
writing from the appropriate individual.
13.5.
Protocol Amendments
Any amendment to this protocol must be approved by the Celgene Clinical Research 
Physician/Medical Monitor.  Amendments will be submitted to the IRB/EC for written approval.  
Written approval must be obtained before implementation of the amended version occurs.  The 
written signed approval from the IRB/EC should specifically reference the Investigator name, 
protocol number, study title and amendment number(s) that is applicable. Amendments that are 
administrative in nature do not require IRB/IEC approval but will be submitted to the IRB/IEC 
for information purposes.
13.6.
Institutional Review Board/Independent Ethics Committee Review 
and Approval
Before the start of the study, the study protocol, ICF, and any other appropriate documents will 
be submitted to the IRB/EC with a cover letter or a form listing the documents submitted, their 
dates of issue, and the site (or region or area of jurisdiction, as applicable) for which approval is 
sought. If applicable, the documents will also be submitted to the authorities in accordance with 
local legal requirements.
IP can only be supplied to an Investigator by Celgene or its authorized representative after 
documentation on all ethical and legal requirements for starting the study has been received by 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
107
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
Celgene or its authorized representative. This documentation must also include a list of the 
members of the IRB/EC and their occupation and qualifications. If the IRB/EC will not disclose 
the names, occupations and qualifications of the committee members, it should be asked to issue 
a statement confirming that the composition of the committee is in accordance with GCP. For 
example, the IRB General Assurance Number may be accepted as a substitute for this list. 
Formal approval by the IRB/EC should mention the protocol title, number, amendment number 
(if applicable), study site (or region or area of jurisdiction, as applicable), and any other 
documents reviewed. It must mention the date on which the decision was made and must be 
officially signed by a committee member. Before the first subject is enrolled in the study, all 
ethical and legal requirements must be met.
The IRB/EC and, if applicable, the authorities, must be informed of all subsequent protocol 
amendments in accordance with local legal requirements. Amendments must be evaluated to 
determine whether formal approval must be sought and whether the ICF should also be revised.
The Investigator must keep a record of all communication with the IRB/EC and, if applicable, 
between a Coordinating Investigator and the IRB/EC. This statement also applies to any 
communication between the Investigator (or Coordinating Investigator, if applicable) and 
regulatory authorities.
Any advertisements used to recruit subjects for the study must be reviewed by Celgene and the 
IRB/EC prior to use.  
13.7.
Ongoing Information for Institutional Review Board/ Ethics 
Committee
If required by legislation or the IRB/EC, the Investigator must submit to the IRB/EC:
∀
Information on serious or unexpected adverse events as soon as possible; 
∀
Periodic reports on the progress of the study;
∀
Deviations from the protocol or anything that may involve added risk to subjects.
13.8.
Termination of the Study
Celgene reserves the right to terminate this study prematurely at any time for reasonable medical 
or administrative reasons. Any premature discontinuation will be appropriately documented 
according to local requirements (eg, IRB/EC, regulatory authorities, etc).
The Sponsor may consider closing this trial when data supporting key endpoints and objectives 
of the study have been analyzed.  In the case where there are subjects still being administered the 
investigational product, and it is the opinion of the Investigator(s) that these subjects continue to 
receive benefit from treatment, the Sponsor may choose to initiate an open-label, roll-over or 
extension study under a separate protocol to allow these subjects continued access to luspatercept
following their participation in this study until the drug is commercially available.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
108
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
In addition, the Investigator or Celgene has the right to discontinue a single site at any time 
during the study for medical or administrative reasons such as:
∀
Unsatisfactory enrollment;
∀
GCP noncompliance;
∀
Inaccurate or incomplete data collection;
∀
Falsification of records;
∀
Failure to adhere to the study protocol.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
109
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
14.
DATA HANDLING AND RECORDKEEPING
14.1.
Data/Documents
The Investigator must ensure that the records and documents pertaining to the conduct of the 
study and the distribution of the investigational product are complete, accurate, filed and 
retained.  Examples of source documents include: hospital records; clinic and office charts; 
laboratory notes; memoranda; subject’s diaries or evaluation checklists; dispensing records; 
recorded data from automated instruments; copies or transcriptions certified after verification as 
being accurate copies; microfiche; x-ray film and reports; and records kept at the pharmacy, and 
the laboratories, as well as copies of eCRFs or CD-ROM.
14.2.
Data Management
Data will be collected via eCRF and entered into the clinical database per Celgene standard 
operating procedures (SOPs). This data will be electronically verified through use of 
programmed edit checks specified by the clinical team.  Discrepancies in the data will be brought 
to the attention of the clinical team, and investigational site personnel, if necessary.  Resolutions 
to these issues will be reflected in the database.  An audit trail within the system will track all 
changes made to the data.
14.3.
Record Retention
Essential documents must be retained by the Investigator according to the period of time outlined 
in the clinical trial agreement. The Investigator must retain these documents for the time period 
described above or according to local laws or requirements, whichever is longer. Essential 
documents include, but are not limited to, the following:
∀
Signed ICFs for all subjects;
∀
Subject identification code list, screening log (if applicable), and enrollment log;
∀
Record of all communications between the Investigator and the IRB/EC;
∀
Composition of the IRB/EC;
∀
Record of all communications between the Investigator, Celgene, and their authorized 
representative(s);
∀
List of Sub-investigators and other appropriately qualified persons to whom the 
Investigator has delegated significant study-related duties, together with their roles in 
the study, curriculum vitae, and their signatures;
∀
Copies of CRFs (if paper) and of documentation of corrections for all subjects;
∀
IP accountability records;
∀
Record of any body fluids or tissue samples retained;
∀
All other source documents (subject records, hospital records, laboratory records, 
etc.); 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
110
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
∀
All other documents as listed in Section 8 of the ICH consolidated guideline on GCP 
(Essential Documents for the Conduct of a Clinical Trial).
The Investigator must notify Celgene if he/she wishes to assign the essential documents to 
someone else, remove them to another location or is unable to retain them for a specified period.  
The Investigator must obtain approval in writing from Celgene prior to destruction of any 
records. If the Investigator is unable to meet this obligation, the Investigator must ask Celgene 
for permission to make alternative arrangements. Details of these arrangements should be 
documented. 
All study documents should be made available if required by relevant health authorities. 
Investigator or institution should take measures to prevent accidental or premature destruction of 
these documents.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
111
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
15.
QUALITY CONTROL AND QUALITY ASSURANCE
All aspects of the study will be carefully monitored by Celgene or its authorized representative
for compliance with applicable government regulations with respect to current GCP and SOPs.
15.1.
Study Monitoring and Source Data Verification
Celgene ensures that appropriate monitoring procedures are performed before, during and after 
the study.  All aspects of the study are reviewed with the Investigator and the staff at a study 
initiation visit and/or at an Investigators’ Meeting.  Prior to enrolling subjects into the study, a 
Celgene representative will review the protocol, eCRFs, procedures for obtaining informed 
consent, record keeping, and reporting of AEs/SAEs with the Investigator.  Monitoring will 
include on-site visits with the Investigator and his/her staff as well as any appropriate 
communications by mail, email, fax, or telephone.  During monitoring visits, the facilities, 
investigational product storage area, eCRFs, subject’s source documents, and all other study 
documentation will be inspected/reviewed by the Celgene representative in accordance with the 
Study Monitoring Plan.
Accuracy will be checked by performing source data verification that is a direct comparison of 
the entries made onto the eCRFs against the appropriate source documentation.  Any resulting 
discrepancies will be reviewed with the Investigator and/or his/her staff.  Any necessary 
corrections will be made directly to the eCRFs or via queries by the Investigator and/or his/her 
staff. Monitoring procedures require that informed consents, adherence to inclusion/exclusion 
criteria and documentation of SAEs and their proper recording be verified.  Additional 
monitoring activities may be outlined in a study-specific monitoring plan.
15.2.
Audits and Inspections
In addition to the routine monitoring procedures, a Good Clinical Practice Quality Assurance 
unit exists within Celgene.  Representatives of this unit will conduct audits of clinical research 
activities in accordance with Celgene appropriate SOPs to evaluate compliance with Good 
Clinical Practice guidelines and regulations.
The Investigator is required to permit direct access to the facilities where the study took place, 
source documents, eCRFs and applicable supporting records of study subject participation for 
audits and inspections by IRB/ECs, regulatory authorities (eg, the Food and Drug Administration 
[FDA], European Medicines Agency [EMA], Health Canada) and company authorized 
representatives.  The Investigator should make every effort to be available for the audits and/or 
inspections.  If the Investigator is contacted by any regulatory authority regarding an inspection, 
he/she should contact Celgene immediately.
15.3.
Product Quality Complaint
A Product Quality Complaint (PQC) is any written, electronic, or oral communication that 
alleges deficiencies related to the identity, quality, durability, reliability, safety, effectiveness, 
purity, or performance of any drug product manufactured by or on behalf of Celgene Corporation 
after it is released for distribution.  PQCs may reduce the usability of the product for its intended 
function or affect performance of the product and therefore pose a significant risk to the subject.  
Examples of PQCs include (but are not limited to): mixed product, mislabeling, lack of effect, 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
112
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
seal/packaging breach, product missing/short/overage, contamination, suspected falsified, 
tampered, diverted or stolen material, and general product/packaging damage. If you become 
aware of a suspected PQC, you are obligated to report the issue immediately.  You can do so by 
emailing 
 or by contacting 
 
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EDMS Doc. Number:
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Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
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ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
16.
PUBLICATIONS
As described in Section 13.2, all protocol- and amendment-related information, with the 
exception of the information provided by Celgene on public registry websites, is considered 
Celgene confidential information and is not to be used in any publications.  Celgene protocol-
related information proposed for use in a publication must be submitted to Celgene for review 
and approval, and should not be utilized in a publication without express written approval from 
Celgene, or as described in the Clinical Trial Agreement.  
Celgene will ensure Celgene-sponsored studies are considered for publication in the scientific 
literature in a peer-reviewed journal, irrespective of the results.  At a minimum, this applies to 
results from all Phase 3 clinical studies, and any other study results of significant medical 
importance.  This also includes results relating to investigational medicines whose development 
programs have been discontinued.
Study results may also be presented at one or more medical congresses, and may be used for 
scientific exchange and teaching purposes.  Additionally, this study and its results may be 
submitted for inclusion in all appropriate health authority study registries, as well as publication 
on health authority study registry websites, as required by local health authority regulations.  
 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
114
ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
17.
REFERENCES
Angelucci E, Brittenham GM, McLaren CE, et al. Hepatic iron concentration and total body iron 
stores in thalassemia major. N Engl J Med 2000;343(5):327-31.
Angelucci E, Baronciani, D. Allogeneic stem cell transplantation for thalassemia major. 
Haematologica 2008;93(12):1780-4.
Attie K, Allison MJ, McClure T et al. A phase 1 study of ACE-536, a regulator of erythroid
differentiation, in healthy volunteers. American Journal of Hematology 20014, 2014 
Jul;89(7):766-70
Cao A, Galanello R. Beta-thalassemia.  Genet Med 2010;12(2):61-76.
Cappellini MD, Robbiolo L, Bottasso BM, et al. Venous thromboembolism and 
hypercoagulability in splenectomized patients with thalassaemia intermedia. Br J Haematol 
2000;111(2):467-73.
Cappellini MD, Cohen A, Piga A, et al. A phase 3 study of deferasirox (ICL670), a once-daily 
oral iron chelator, in patients with beta-thalassemia. Blood 2006;107(9):3455-62.
Cappellini MD. Hemoglobinopathies: the thalassemias. Fondazione IRCCS “Ca Granda” 
Policlinico.  Univ of Milan – Italy; 2014.
Cappellini MD, Viprakasit V, Taher AT. An overview of current treatment strategies for β-
thalassemia, 2014a.
Cohen AR, Glimm E, Porter J. Effect of transfusional iron intake on response to chelation 
therapy in beta-thalassemia major. Blood 2008;111(2):583-7.
Colah R, Gorakshakar A, Nadkarni A. Global burden, distribution and prevention of β-
thalassemias and hemoglobin E disorders. Expert Rev Hematol 2010;3(1):103-17.
Dussiot M, Maciel TT, Fricot A, et al. An activin receptor IIA ligand trap corrects ineffective 
erythropoiesis in β-thalassemia. Nat Med 2014;20(4):398-407.
Fibach E, Rachmilewitz E. Does erythropoietin Have a role in the treatment of 
β-hemoglobinopathies? Hematol Oncol Clin N Am 2014;28(2):249-63.
Fucharoen S, Weatherall DJ. The hemoglobin E thalassemias. Cold Spring Harb Perspect Med 
2012;2(8):a011734.
Gabutti V, Piga A. Results of long-term iron-chelating therapy. Acta Haematol 1996;95(1):26-
36.
Galanello R, Origa R. Beta-thalassemia. Orphanet J Rare Dis 2010;5:11.
Gardenghi S, Marongiu MF, Ramos P, et al. Ineffective erythropoiesis in beta-thalassemia is 
characterized by increased iron absorption mediated by down-regulation of hepcidin and up-
regulation of ferroportin. Blood 2007;109(11):5027-35.
Ginzburg Y, Rivella S. β-thalassemia: a model for elucidating the dynamic regulation of 
ineffective erythropoiesis and iron metabolism. Blood 2011;118(16):4321-30.
Guidelines for the Management of Non Transfusion Dependent Thalassaemia (NTDT). 
Thalassemia International Federation. 2013, TIF Publication No 19.
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ato
CL670), a o
CL670), a o
):3455
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-62
e IRCCS “
e IRCCS 
urrent treatm
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11(2)
(2):583
:583-7
-
burden, di
urden, d
Expert Rev
Expert Rev
An act
An activini
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Med 201
es ery
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A. Results o
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EDMS Doc. Number:
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Protocol ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
115
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Guidelines for the Management of Transfusion Dependent Thalassaemia, 3rd Edition, 2014.
Klaassen JB, et al. Validation and reliability of a disease-specific quality of life measure (the 
TranQol) in adults and children with thalassaemia major. Br J Haematol, 2014;164(3),431-7.
Mabaera R, West RJ, Conine SJ, Macari ER, Boyd CD, Engman CA, Lowrey CH. A cell stress 
signaling model of fetal hemoglobin induction: what doesn’t kill red blood cells may make them 
stronger. Exp Hematol 2008;36(9):1057-1072.
Massague J. TGF-beta signal transduction. Annu Rev Biochem 1998;67:753-91.
Modell B, Darlison M, Birgens H, et al. Epidemiology of haemoglobin disorders in Europe: an 
overview. Scand J Clin Lab Invest 2007;67(1):39-69.
Modell B, Darlison M. Global epidemiology of haemoglobin disorders and derived service 
indicators. 2008; WHO (Bulletin).  Available at: http://www.who.int/bulletin/volumes/86/6/06-
036673/en/.
Musallam KM, Khoury B, Abi-Habib R, Bazzi L, Succar J, Halawi R, et al. Health-related 
quality of life in adults with transfusion-independent thalassaemia intermedia compared to 
regulatory transfused thalassaemia major: new insights. Eur J Haematol 2011;87(1):73-9.
Musallam KM, Rivella S, Vichinsky E, and Rachmilewitz EA. Non-transfusion-dependent 
thalassemias. Haematologica 2013; 98(6):833 – 844.
Nathan DG, Gunn RB. Thalassemia: the consequences of unbalanced hemoglobin synthesis. Am 
J Med 1966,41(5):815-30.
Oken MM, Creech RH, Tormey DC, Horton J, Davis TE, McFadden ET, et al. Toxicity and 
response criteria of the Eastern Cooperative Oncology Group, Am J Clin Oncol 1982
Dec;5(6):649-55.
Olivieri N, Brittenham GM. Iron-chelating therapy and the treatment of thalassemia. Blood 
1997; 89(3);739-61.
Olivieri N. The beta-thalassemias. N Engl J Med 1999;341(2):99-109.
Piga A, Serra M, Longo F, et al. Changing patterns of splenectomy in transfusion-dependent 
thalassemia patients. Am J Hematol 2011;86(9):808-10.
Porter J. Practical management of iron overload. B J Haematol 2001;115(2):239-52.
Rachmilewitz EA, Aker M. The role of recombinant human erythropoietin in the treatment of 
thalassemia. Ann NY Acad Sci 1998;850:129-38.
Ribeil JA, Arlet JB, Dussiot M, et al. Ineffective erythropoiesis in β-thalassemia. Scientific 
World Journal 2013;28:394295.
Rund D, Rachmilewitz, E. Beta-thalassemia. N Engl J Med 2005;353(11):1135-46.
Sabloff M, Chandy M, Wang Z, et al. HLA-matched sibling bone marrow transplantation for β-
thalassemia major. Blood 2011;117 (5):1745-50.
Sankaran VG, Nathan DG. Thalassemia: an overview of 50 years of clinical research. Hematol 
Oncol Clin North Am. 2010;24(6):1005-20.
Standards for the Clinical Care of Children and Adults with Thalassaemia (SCCCAT), 2008.
CCI
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Suragani RN, Cawley SM, Li R, et al. Modified activin receptor IIB ligand trap mitigates 
ineffective erythropoiesis and disease complications in murine β-thalassemia Blood 
2014;123(25):3864-72.
Suragani RN, Cadena SM, Cawley SM, et al. Transforming growth factor-β superfamily ligand 
trap ACE-536 corrects anemia by promoting late-stage erythropoiesis. Nat Med
2014a;20(4):408-14.
Taher A, Sheikh-Taha M. Hydroxyurea use in Lebanese patients with beta-thalassemia 
intermedia. J Pediatr Hematol Oncol. 2006;28(2):107.
Taher AT, Musallam KM, Karimi M, et al. Overview on practices in thalassemia intermedia 
management aiming for lowering complication rates across a region of endemicity: the 
OPTIMAL CARE study. Blood 2010;115(10):1886-92.
Taher AT, Porter J, Viprakasit V, et al. Deferasirox reduces iron overload significantly in 
nontransfusion-dependent thalassemia: 1-year results from a prospective, randomized, double-
blind, placebo-controlled study. Blood 2012;120(5):970-7.
Tanner MA, Galanello R, Dessi C, et al. A randomized, placebo-controlled, double-blind trial of
the effect of combined therapy with deferoxamine and deferiprone on myocardial iron in 
thalassemia major using cardiovascular magnetic resonance. Circulation 2007;115(14):1876-84.
Thein SL. The molecular basis of β-thalassemia. Cold Spring Harb Perspect Med 
2013;3(5):a011700.
Thompson AA, Cunningham MJ, Singer ST, et al. Red cell alloimmunization in a diverse 
population of patients with thalassaemia. Br J Haematol 2011;153(1):121-8.
Viprakasit V, Gattermann N, Lee JW, et al. Geographical variations in current clinical practice 
on transfusions and iron chelation therapy across various transfusion-dependent anaemias. Blood 
Transfus 2013; 11: 108-22
Voskaridou E, Ladis V, Kattamis A, et al. A national registry of haemoglobinopathies in Greece:
deducted demographics, trends in mortality and affected births. Ann Hematol 2012;91(9):1451-
8.
Weatherall DJ, Clegg JB, Naughton MA. Globin synthesis in thalassemia: An in vivo study. 
Nature, 1965;208:1061-65.
Weatherall DJ. Phenotype-genotype relationships in monogenic disease: lessons from the 
thalassaemias. Nat Rev Genet 2001;2(4):245-55.
Weatherall DJ. The inherited diseases of hemoglobin are an emerging global health burden. 
Blood 2010;115(22):4331-6.
Weiss MJ, dos Santos CO. Chaperoning erythropoiesis. Blood 2009;113(10):2136-44.
Zermati Y, Fichelson S, Valensi F, et al. Transforming growth factor inhibits erythropoiesis by 
blocking proliferation and accelerating differentiation of erythroid progenitors. Exp Hematol 
2000;28(8):885-94.
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18.
APPENDICES
Appendix A:  Table of Abbreviations
Table 6:
Abbreviations and Specialist Terms
Abbreviation or 
Specialist Term
Explanation
ActRIIB
Activin receptor type IIB
ADA
Antidrug antibody
AE
Adverse event
ALT
Alanine aminotransferase (SGPT)
ANC
Absolute neutrophil count
ANCOVA
Analysis of covariance
AST
Aspartate aminotransferase (SGOT)
ATG
Anti-thymocite globulin
AUC
Area under the curve
β-hCG
β-subunit of human chorionic gonadotropin
BMD
Bone mineral density
BSC
Best supportive care
BUN
Blood urea nitrogen
CI
Confidence interval
CFR
Code of Federal Regulations
Cmax
Maximum plasma concentration of drug
CMH
Cochran Mantel-Haenszel
CSR
Clinical Study Report
CTCAE
Common Terminology Criteria for Adverse Events
DFO
Deferoxamine
DFP
Deferiprone
DFX
Deferasirox
DMC
Data Monitoring Committee
dw
Dry weight
DXA
Dual energy x-ray absorptiometry
EC
Ethics Committee
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Table 6:
Abbreviations and Specialist Terms (Continued)
Abbreviation or 
Specialist Term
Explanation
ECD
Extracellular domain
ECG
Electrocardiogram
ECOG
Eastern Cooperative Oncology Group
eCRF
Electronic case report form
EEA
European Economic Area
EMA
European Medicines Agency
EPO
Erythropoietin
ESA
Erythropoiesis-stimulating agent
EU
European Union
FCBP
Female of childbearing potential
FDA
Food and Drug Administration
GCP
Good Clinical Practice
HbF
Fetal hemoglobin
Hb
Hemoglobin
Hct
Hematocrit
HCV
Hepatitis C virus
HIV
Human immunodeficiency virus
HLA
Human leukocyte antigen
HRU
Healthcare Resource Utilization
HSCT
Hematopoietic stem cell transplantation
IB
Investigator’s Brochure
ICF
Informed consent form
ICH
International Conference on Harmonisation
ICT
Iron chelation therapy
ID
Identification
IND
Investigational New Drug
IP
Investigational Product
IRB
Institutional Review Board
IRT
Integrated Response Technology
ITT
Intent-to-treat (subjects)
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Table 6:
Abbreviations and Specialist Terms (Continued)
Abbreviation or 
Specialist Term
Explanation
IWRS
Integrated Web Response System
LDH
Lactic dehydrogenase
LIC
Liver iron concentration
LMW
Low-molecular-weight
LLN
Lower limit of the normal
LVEF
Left ventricular ejection fraction
MAA
Marketing authorization application
MCH
Mean corpuscular hemoglobin
MCHC
Mean corpuscular hemoglobin concentration
MCV
Mean corpuscular volume
MedDRA
Medical Dictionary for Regulatory Activities
MRI
Magnetic resonance imaging
ms
milliseconds
MUGA
Multi Gated Acquisition Scan
NCI
National Cancer Institute
NTD
Non-transfusion dependent
NYHA
New York Heart Association
PK
Pharmacokinetics
PQC
Product Quality Complaint
QoL
Quality of Life
RBC
Red blood cell count
RDW
Red blood cell distribution width
ROS
Reactive oxygen species
SAE
Serious adverse event
SAP
Statistical Analysis Plan
SC
Subcutaneous(ly)
SD
Standard deviation
SF
Short Form
SGOT
Serum glutamic oxaloacetic transaminase 
SGPT
Serum glutamic pyruvic transaminase
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Table 6:
Abbreviations and Specialist Terms (Continued)
Abbreviation or 
Specialist Term
Explanation
SOP
Standard operating procedure
SUSAR
Suspected unexpected serious adverse reaction
TD
Transfusion dependent
t1/2
Half-life
tmax
Mean time to Cmax
ULN
Upper limit of normal
TEAE
Treatment-emergent adverse event
TGF-β
Transforming growth factor-β
TRV
Tricuspid regurgitant velocity
WBC
White blood cell
WFI
Water for injection
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Appendix B: ECOG Performance Status Scale
The Eastern Cooperative Oncology Group (ECOG) scale (Oken, 1982) is used to assess a 
patient’s quality of life in an evaluation by a health professional of the daily activities and how 
the activities are affected by the disease of the patient.
ECOG Performance Status Scale
Score
Description
0
Fully active, able to carry on all pre-disease performance without restriction
1
Restricted in physically strenuous activity but ambulatory and able to carry out work of 
a light or sedentary nature, eg, light housework, office work.
2
Ambulatory and capable of all self-care but unable to carry out any work activities.  Up 
and about more than 50% of waking hours.
3
Capable of only limited self-care, confined to bed or chair more than 50% of waking 
hours.
4
Completely disabled.  Cannot carry on any self-care.  Totally confined to bed or chair
5
Dead
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Appendix C: National Cancer Institute (NCI) Common Terminology Criteria 
for Adverse Events (CTCAE) Version 4.0
Currently active minor version of NCI CTCAE, Version 4.0:
http://evs.nci.nih.gov/ftp1/CTCAE/CTCAE_4.03_2010-06-14_QuickReference_8.5x11.pdf
http://www.oncology.tv/SymptomManagement/NationalCancerInstituteUpdatesCTCAEtov403.a
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Appendix D:  New York Heart Association - Classification of Heart Failure
New York Heart Association - Classification of Heart Failure
Class
Symptoms
Class 1
No limitation of activities.  No symptoms from ordinary activities
Class 2
Mild limitation of activity.  Comfortable with rest or mild exertion
Class 3
Marked limitation of activity and be comfortable only at rest
Class 4
Complete rest, confined to bed or chair; any physical activity brings on discomfort and 
symptoms occur at rest
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Appendix E:  List with Countries within each Region
Table 7:
Countries Within Each Region
Countries included in each Geographical region may include, but are not limited to:
North America & Europe
Middle East & North Africa
Asia-Pacific
Bulgaria
Algeria
Australia
Canada
Egypt
Hong Kong
France
Israel
Malaysia
Germany
Lebanon
Taiwan
Greece
Morocco
Thailand
Italy
Oman
Hungary
Saudi Arabia
United Kingdom
Tunisia
Unites States
Turkey
United Arab Emirates
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the organizations electronic signature policies and procedures.
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EDMS Doc. Number:
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Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
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ACE-536-B-THAL-001 Amendment 2 Final: 11 Dec 2018
1.
JUSTIFICATION FOR AMENDMENT
Significant changes included in this amendment are summarized below.  These changes were 
based on feedback obtained from the Health Authorities, and internal discussions.
1.1.
Dose Modifications: Dose Delay, Dose Reduction and 
Discontinuation Guidelines
 additional criteria for dose adjustment have
been introduced, ie:
-
Dose delay for condition of worsening of anemia, as described in Table 5 and Dose 
discontinuation, if hematological malignancy is confirmed
-
Dose delay for condition of Grade ≥ 3 leukopenia, neutropenia and/or thrombocytopenia,
and dose discontinuation if hematological malignancy is confirmed
Revised Sections: Section 7.2, Section 7.2.1.2, Table 5
1.2.
Other Minor Clarification and Corrections 
The amendment also includes several other minor clarifications and corrections:
1.2.1.
Correction of Typos Identified in the Document:
∀
Section 3.2. Study Duration for Subjects: End of Study for each individual subject: 
Instead of “96-week Post Treatment Follow-up” it should read “156-week Post 
Treatment Follow-up”
∀
Section 9.9.1.1. Clinical Study Report for Marketing Authorization Application : 
clarified that the data cut-off date for the CSR for MAA as described in the Protocol 
Section 9.9.1.1 will be at the time “when all subjects completed 48 weeks of a double-
blind Treatment Period or discontinued before reaching 48 weeks”. The following 
clarifier has been removed “The CSR for MAA will include TEAEs reported for 9 
weeks post last dose.” Since the Clinical data base will remain open to collect any 
TEAEs reported for 9 weeks post last dose and related AEs until the End of Study (as 
already clarified in Section 5, Table 3, as well as Section 10.1. Thus, in the scenario if 
the last subjects discontinue treatment within the 9 weeks of the predefined data base 
cut-off date for the CSR for the MAA all available TEAEs will be added to an updated 
report to the Agency, upon request.
∀
Section 3.1.3. Long-term Treatment Period: to align the duration of the Long-Term 
Treatment Period and the timing of unblinding with the information in Section 9.9.1.1, 
the following clarification has been updated: Subjects who continue to receive treatment 
with luspatercept or placebo when the study is unblinded (approximately a maximum 48 
weeks after the first dose of the last subject and upon the database lock) may opt to 
continue receiving luspatercept in the Open-label Phase or to discontinue treatment and 
enter the Post-Treatment Follow-up Period
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∀
Protocol Summary: corrected typo “no transfusion-free period > 35 days”, instead of “ > 
45 days".
∀
Sections 6.2, Section 6.3, Section 6.4, Section 6.5, Section 6.6.1: “abnormal ultrasound” 
it should read “abdominal ultrasound”
∀
Section 15.3 Product Quality Compliant was added to clarify the process for 
communicating any PQC issue to Celgene Customer Care Center.
∀
In the Table of Events, Table 3, clarifications have been added to the serum chemistry, 
urinalysis and serum ferritin that these assessment are evaluated by local laboratory in 
the Open-label Phase of the study. 
∀
Additional editorial revisions or minor clarifications
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EDMS Doc. Number:
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ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
1.
JUSTIFICATION FOR AMENDMENT
Significant changes included in this amendment are summarized below.  These changes were 
based on feedback obtained from the Health Authorities, Ethic Committees, Investigators, 
Steering Committee (SC), Data Monitoring Committee (DMC) and internal discussions.
 
 
  
 
 
 
 
 
 
 
 
 
 
 
1.2.
Study Design
1.2.1.
Placebo subjects: Allow all subjects, regardless of the initial treatment to which 
they have been randomized in the double-blind Treatment Period, to receive 
active treatment in the Open-label Phase. 
Rationale: 
In the last quarter of 2015 and during the course of 2016, 
 
 as well as Investigators participating in the ACE-536-B-THAL-001 study, have 
commented that it is unethical towards subjects participating in this study, to not allow all 
subjects to receive active drug in the Open-label Phase of the study. Based on feedback received 
from investigators, the biggest challenge for enrollment in this study will be subject’s skepticism 
of being enrolled in the placebo arm, and thus subjects perception that there is no benefit for 
them in participating in the study if they are in the placebo group. In December 2015, Celgene 
met with the DMC and SC for this study to share the feedback received. Both DMC and SC 
committees were in agreement for the current protocol to be modified to allow all subjects
regardless of the initial treatment they have been assigned to in the double-blind Treatment 
Period to have the opportunity to receive active treatment in an Open-label Phase. On 16 Dec 
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2015, Celgene signed a formal letter indicating Celgene commitment in amending the protocol to 
allow all subjects to receive activate treatment in an Open-label Phase. In June 2016, Celgene 
further met with the study SC and presented the proposed modified study design: the modified 
study design laid down in this protocol Amendment 1 has been discussed and was agreed upon 
by the SC at the 10 Jun 2016 SC meeting.
Revised Sections: Section 3.1.3, 3.1.4, 3.1.5, 3.2, 3.3, 6.4, Table 3, Figures 4 and 5, and the 
Protocol Summary.
1.2.2.
Inclusion of the Open-label Extension study as part of the current study, ie, the 
Open-label Phase and not a separate study
Rationale:
Based on internal discussions, Celgene considered for practical reasons to incorporate the Open-
label Extension study, initially mentioned as a separate study, as part of this ongoing study. This 
approach has been considered as more practical from subject and site perspective, and will avoid 
moving subjects from one study to a new one, as well as avoid multiple administrative 
procedures at the site level, such as closing and opening of the studies. This item has been 
reviewed and was agreed upon by the study SC following the 10 Jun 2016 meeting.
Revised Sections: Section 3.1.3, 3.1.4, 3.1.5, 3.2, 3.3, 6.4, Table 3, Figures 4 and 5.
1.2.3.
Open-label Phase design
Rationale:
The initiation and duration of the Open-label Phase as outlined in this Amendment 1 is: Open-
label Phase will begin after the study unblinding. The commencement of this Open-label Phase 
will be determined by the enrollment rate and by the availability of primary analysis data that 
justify the use of luspatercept in an Open-label Phase, which will be reviewed by the independent 
external DMC. After DMC review of safety and efficacy, DMC will determine if the use of 
luspatercept in subjects previously randomized to receive placebo in this Open-label phase is 
safe and recommended, and if subjects already on luspatercept can continue to be treated at 
their current dose level (best supportive care is allowed). In the Open-label Phase, subjects may 
receive luspatercept until all subjects initially assigned to luspatercept in the double-blind 
Treatment Period, complete the total treatment duration of 5 years from subjects’ Dose 1 Day 1 
in the treatment period of this ACE-536-B-THAL-001 study or discontinue early.
For subjects initially assigned to luspatercept:
-
It has been clarified that subjects initially assigned to luspatercept should not have 
discontinued the double-blind phase, in order to be eligible for the Open-label Phase.
Thus, subjects that have been already assigned to active treatment and who are 
experiencing benefit of being on active treatment can continue in the Open-label Phase.
For subjects initially assigned to placebo: 
-
It has been clarified that subject initially assigned to placebo can enter the Open-label 
Phase even if they have discontinued the double-blind phase, but were compliant with the 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
5
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
protocol 48 weeks post Dose 1 Day 1, and continue their participation in the Post-
treatment Follow-up Period until the time of unblinding. 
The compliance with the protocol 48 weeks post Dose 1 Day 1 is needed to allow 
evaluation of the primary and key secondary endpoints. The visit schedule in the Post-
treatment Follow-up Period is a very light schedule approximately every 24 weeks, so 
that the visit burden to the subject is decreased at a minimum up to the time of 
unblinding. 
-
It has been clarified that placebo subjects who discontinued treatment and continued their 
participation in the Post-treatment Follow-up Period until the time of unblinding will 
have the opportunity to enter the Open-label Phase, if they still fulfill the main 
eligibility criteria, prior to receiving their first dose of luspatercept.
The main safety/comorbidity eligibility criteria has been considered as a condition to 
enter the Open-label Phase. 
Revised Sections: Section 3.1.4
1.2.4.
Extended the Post-treatment Follow-up Period (post last dose follow-up) from 9 
weeks to 156 weeks.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
6
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
 
Revised Sections: Section 3.1.5, 3.2, 3.3, 11.1, and the Protocol Summary. 
1.2.5.
Overall Study Design figure and Subject Management Figure
Rationale:
To reflect the change in the study design, the Study Design Figure 4 has been updated. In 
addition to further provide practical guidance to the sites on subject flow management within the 
study from Screening/Run-in up to the End of Study, a Subject Management Decision Tree has 
been created.
Revised Sections: Figure 4 and Figure 5
1.2.6.
Inclusion of malignancy and pre-malignancy reporting in Post-treatment 
Follow-up
Rationale:
 
As described in the protocol: The occurrence of a new malignancy or pre-malignant lesion will 
be monitored and collected as an event of interest and should be included as part of the 
assessment of adverse events throughout the course of the study. Investigators are to report the
development of any new malignancy or pre-malignant lesion as a serious adverse event,
regardless of causal relationship to IP (study drug[s] or control), occurring at any time for the 
duration of the study, from the time of signing the ICF up to and including 156 weeks of follow-
up (refer to Section 10 for additional information). 
This item has been reviewed with the study SC following the 10 Jun 2016 meeting.
Revised Sections: Section 5 (Table 3, Table of Events), Sections 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.6.1, 
6.7, 10.1, and 10.5.2.
1.2.7.
Implementing subject diary for transfusion received outside of the regular 
transfusion center
Rationale:
Implementation of a diary in order to capture any transfusions occurring outside the investigation 
site, when there is not an established plan in place. The intention is to increase the accuracy of
the transfusions and hemoglobin data record. This item has been reviewed and was agreed upon 
by the study SC at the 10 Jun 2016 meeting.
Revised Sections: Section 5 (Table 3, Table of Events), Sections 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.6.1.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
7
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
1.2.8.
Provide flexibility between the Randomization call and Dose 1 Day 1 from 24
hours to 3 days
Rationale: 
For practical reasons at the sites per feedback received from the Investigators. This item has been 
reviewed and was agreed upon by the study SC following the 10 June 2016 meeting.
Revised Section: Section 3.1.2
1.2.9.
Allow the transfusion to be administered at Dose 1 Day 1
Rationale:
Per Investigators’ feedback and request - for practical reasons to avoid bringing the subjects to 
the site for additional visits.
If a transfusion occurs on Dose 1 Day 1, the first dose of luspatercept should not be given within 
1 hour before the start of the transfusion, or 2 hours after the end of the transfusion is
implemented to avoid confounding factors in the event of a patient reaction to either a 
transfusion or to the first dose of study medication.
Revised Section: Section 3.1.2
1.3.
Eligibility Criteria
1.3.1.
Inclusion criterion 4 –clarification to β-thalassemia diagnosis in regards to the 
mutation profile and changed to Inclusion criterion 4 instead of Exclusion 
criterion 4
Rationale:
For clarity, based on Investigators’ feedback.  This item has been reviewed and was agreed upon 
by the study SC following the 10 Jun 2016 meeting.
Revised Sections: Sections 4.2 and Section 4.3 
1.3.2.
Inclusion criteria 7 and 8 – contraception language: updated language to list 
acceptable contraception methods
Rationale:
 
 The protocol was amended to include details of 
effective contraception for women of childbearing potential. The protocol should be consistent 
with regards to the terms “adequate contraception” and “effective contraception.” This item has 
been reviewed and was agreed upon by the study SC following the 10 Jun 2016 meeting.
Revised Section: Section 4.2
1.3.3.
Exclusion criterion 5 – clarified definition of active hepatitis B and hepatitis C
Rationale: 
Based on requests received from Investigators to clarify this eligibility criterion.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
8
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
Revised Section: Section 4.3
1.3.4.
Exclusion criterion 7 – clarified chronic anticoagulant therapy uses in the 
context of exclusion criterion
Rationale: 
It has been clarified that the anticoagulant therapies used for prophylaxis for surgery or high risk 
procedures as well as low-molecular-weight (LMW) heparin for superficial venous thrombosis 
and chronic aspirin are allowed. This change has been implemented based on requests received 
from Investigators to clarify this eligibility criterion.
Revised Section: Section 4.3
1.3.5.
Exclusion criterion 9 – clarified insulin-dependent diabetes, ie, chronic 
treatment with insulin criterion to specify: “Poorly controlled diabetes mellitus 
within 24 weeks prior to randomization as defined by short term (eg, hyperosmolar 
or ketoacidotic crisis) and/or history of diabetic cardiovascular complications (eg,
stroke or myocardial infarction).”
Rationale: 
Clarification as per Investigators request. Excluding subjects prone to complex concomitant 
medical issues that may interfere with the study participation and the safety data irrespective of 
insulin dependency. This item has been reviewed and was agreed upon by the study SC 
following the 10 June 2016 meeting.
Revised Section: Section 4.3
1.3.6.
Exclusion criterion 17 a) – simplified the cirrhosis evidence in the exclusion 
criterion
Rationale: 
Based on feedback received  from Investigators, to allow subjects with minor liver fibrosis. 
Celgene does not anticipate that luspatercept may worsen the fibrotic process in the liver, and the 
metabolism/elimination of luspatercept does not depend on liver function. This allows
enrollment of subjects with stable, asymptomatic, and uncomplicated liver fibrosis. This item has 
been reviewed and was agreed upon by the study SC following the 10 Jun 2016 meeting.
Revised Section: Section 4.3
1.3.7.
Exclusion criterion 17 c) –added toxicity Grade 3 as per Common Terminology 
Criteria for Adverse Events (CTCAE) as a reference for clinically significant 
lung disease and pulmonary fibrosis
Rationale: 
Based on requests received from Investigators to clarify this eligibility criterion.
Note: Grade 3 CTCAE refers to: 
-
clinically significant pulmonary hypertension is considered severe symptoms associated 
with hypoxemia; right-sided heart failure; oxygen indicated; 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
9
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
-
clinically significant pulmonary fibrosis is considered severe hypoxemia; evidence of 
right-sided heart failure; radiographic pulmonary fibrosis >50 - 75%.
This item has been reviewed and was agreed upon by the study SC following the 10 Jun 2016 
meeting.
Revised Section: Section 4.3
1.3.8.
Exclusion criterion 19 – clarified adrenal insufficiency exclusion criterion to 
specify “Systemic glucocorticoids ≤12 weeks prior to randomization (physiologic 
replacement therapy for adrenal insufficiency is allowed)”
Rationale:
Based on requests received from Investigators to clarify this eligibility criterion. This item has 
been reviewed with the study SC following the 10 Jun 2016 meeting.
Revised Section: Section 4.3
1.3.9.
Exclusion criterion 22 –Examples of immunosuppressant agents were provided
for clarity
Rationale:
Examples of immunosuppressant agents were provided in the exclusion criterion for clarity.
Revised Section: Section 4.3
1.3.10.
Exclusion criterion 23 – exclusion criterion on malignancy were created
Rationale:
Revised Section: Section 4.3
1.4.
Assessments and Procedures
1.4.1.
Eastern Cooperative Oncology Group (ECOG) measurement during study 
treatment was removed; ECOG measurement at eligibility was not changed
Rationale:
Per feedback received from investigators: ECOG evaluation could be very subjective since it 
depends on the investigator assessing the subject; could be a concern if the investigator/sub-
investigator changes from baseline to post-baseline. In addition, performance status is already 
captured during the trial via the Quality of Life (QoL) instruments. This item has been reviewed 
with the study SC following the 10 Jun 2016 meeting.
Revised Sections: Section 5, Table 3; Sections 6.1, 6.2, and 6.4, 6.5, 6.6, 6.7.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
10
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
1.4.2.
Malignancy and Pre-malignancy Reporting implemented in the Table of Events
as well as Procedure Section of the protocol
Rationale:
To address the inclusion of the malignancy and pre-malignancy reporting into the study design 
(see Rationale as described above in Section 1.2.6 of the Justification for Amendment)
Revised Sections: Section 5, Table 3; Sections 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, and 6.7. 
1.4.3.
Subject Transfusion Diary implemented in the Table of Events as well as 
Procedure Section of the protocol
Rationale:
To address the inclusion of the subject diary into the study design (see Rationale as described 
above in Section 1.2.7 of the Justification for Amendment)
Revised Sections: Section 5, Table 3; Sections 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, and 6.6.1. 
1.4.4.
LVEF – MRI technique added as an option, MUGA technique clarified not 
applicable for Germany
Rationale:
MRI technique added as an option – clarification added, as per feedback received  from sites, 
when measuring T2* (already required measurement per protocol), the LVEF can be taken out 
from the same MRI acquisition.
MUGA technique clarified N/A for Germany -
 
. 
Revised Sections: Section 5, Table 3; Sections 6.1, 6.2, 6.3, Protocol Summary.
1.4.5.
Hematology Panel – clarification added reticulocytes and erythroblast to be 
measured by local laboratory
Rationale:
Due to stability of the reticulocytes, shipments from some sites to a central laboratory are not 
possible, thus Celgene decided to require reticulocyte count measurement by local lab.
Erythroblast measurement by an automated machine is a preferable outcome for erythroblast 
reading. Due to a different technique used in the central laboratory, a clarification for local 
measurement is implemented in the protocol. 
Revised Sections: Section 5, Table 3; Sections 6.1, 6.2, 6.3, 6.4, 6.5, 6.6.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
11
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
1.4.6.
Spleen measurement by abdominal ultrasound implemented as technique for 
spleen measurement
Rationale:
Based on feasibility some sites do not use MRI for measuring the spleen. The Investigators 
requested the protocol be changed to allow spleen measurement by ultrasound, which is the 
standard practice at the sites.
Revised Sections: Section 5, Table 3; Sections 6.1, 6.2, 6.3, 6.4, 6.5, 6.6.1.
1.4.7.
DXA measurement removed from Week 24
Rationale:
After additional analysis of Phase 2 data, significant changes in bone metabolisms at week 24 
was not observed. In addition, as per feedback received from investigators Week 24 is too short 
of a time to highlight significant changes in bone metabolism. 
Revised Sections: Section 5, Table 3; Sections 6.1, 6.2, 6.3, 6.4, 6.5, 6.6.1.
 
 
1.4.9.
Visit window increased: to +/- 5 days in Long-term Treatment Period and +/- 10 
days for magnetic resonance imaging (MRI) and dual energy x-ray 
absorptiometry (DXA) assessments
Rationale:
As per Investigator feedback, to allow more flexibility in scheduling assessments and patient
convenience. 
Revised Sections: Section 5, Table 3; Section 6, 6.3.
1.4.10.
Open-label Phase visit and assessments reflected in the Table of Events and 
Procedure Section
Rationale:
To reflect modification to the study design, as described above (Section 1.2.3).
Revised Sections: Section 5, Table 3; Sections 6, 6.4, 6.4.1, and 6.9
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
12
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
1.4.11.
Post-treatment Follow-up: Follow-Up weeks  24, 48, 72, 96, 120, 144 and 156
visits and assessments reflected in the Table of Events and Procedure Section
Rationale:
To reflect modification to the study design, as described above (Section 1.2.4, 1.2.5).
Revised Sections: Section 5, Table 3; Sections 6.6 and 6.7.
1.4.12.
Post-treatment Follow-up assessments on Follow-up week 6, replaced with 
Follow-up week 9
Rationale:
Schedule adjusted to capture the assessments outcome at the end of the period 5 times mean half-
life of the IP.
Revised Sections: Section 5, Table 3 and Section 6.6.
1.4.13.
Collection of ICTs, Post-Medications, transfusions, HRU and AEs changed from 
being recorded on an ongoing basis until end of study to until 9 weeks post last 
dose 
Rationale:
The reporting of these items is kept up to 9 weeks post last dose, considering the 5 times half-
life of the drug. After this period it is considered that the drug will not have effect. For AE, 
reporting of related AE until End of Study is kept unchanged.
Revised Sections: Section 5, Table 3; Sections 6.6, 6.6.1 and 6.7.
1.4.14.
Clarified PK and ADA collection in Long-term Treatment Period and at 
Treatment Discontinuation 
Rationale:
To protect the blinding it has been clarified that ADA results will not be required to decide the 
need of ADA monitoring prior to the study unblinding, with details described as following.  
Long-term Treatment Period: PK and ADA samples will be collected every 6 doses for up to 2 
years from Dose 1 Day 1 of the double blinded treatment period 
Open Label Phase: For placebo-cross-over subjects, only if positive at unblinding, continue 
every 6 doses up to 2 years from Dose 1 Day 1 of the double blinded treatment period. For 
subjects continuing treatment with luspatercept, only if positive at unblinding, every 6 doses up 
to 2 years from Dose 1 Day 1 of the double blinded treatment period.
Post-treatment Follow-up: Before unblinding, ADA monitoring (every 24 weeks) at post-
treatment follow-up visits will continue for up to two years from Dose 1 Day 1 of double-blind 
Treatment Period.  After unblinding, ADA monitoring (every 24 weeks) at all post-treatment 
follow-up visits will continue only if subjects’ last available ADA is positive and they have not 
reached the 2-year maximum limit for ADA monitoring.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
13
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
Revised Sections: Section 5, Table 3; Section 6.9
1.5.
Treatment Administration and IP 
1.5.1.
Clarification to IP Reconstitution and IP stability
Rationale:
As per investigator feedback, the wording on IP reconstitution has been clarified. 
Additional information became available on drug stability since the original protocol version of 
25 Aug 2015, thus the stability of the reconstituted product has been updated from 6 hours to 10 
hours. 
Revised Section: Section 7.1.
1.5.2.
Clarification on placebo supply
Rationale:
Placebo supply language in the protocol has been adjusted to comply at a global scale with local 
country requirements for placebo supply. 
Revised Sections: Sections 7.1, 7.4.1, and Protocol Summary.
1.5.3.
Maximum volume per injection site increase to 1.2 ml. 
Rationale:
In Phase 2 studies, the maximum volume per injection site is 1.2 mL, with acceptable subject 
comport.  Therefore, maximum volume per injection site in the current protocol is increased
from 1 ml to 1.2 ml to decrease the number of injections. . 
Revised Sections: Sections 7.2. 
1.5.4.
Maximum total dose introduced up to 120 mg 
 
Revised Sections: Sections 7.2, 7.2.1.1 and 3.1.2.
1.5.5.
Study Drug Administration: Clarification that the increase hemoglobin (Hb) ≤
2.0 g/dL is to be compared to the pre-dose Hb of Day 1 of the previous treatment 
dose cycle (previous wording “at Day 21 from last dose”)
Rationale:
Clarification for consistency in the wording with protocol Table 5. 
Revised Section: Section 7.2. 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
14
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
1.5.6.
Study Drug Administration: Clarification that the pre-treatment/ pre-
transfusion Hb value should be <11.5 g/dL for dose administration, the notion 
“not influenced by transfusion (ie, ≥14 days post- transfusion)” deleted from the 
paragraph. 
Rationale:
As per received feedback from Investigator, the Sponsor updated this paragraph to avoid 
confusions in regards to the Hb level at the day of the dosing and the time of the transfusions. As 
clarified at the Investigator meetings held in 2016, if the pre-treatment/ pre-transfusion Hb value 
at the date of the dosing is < 11.5 g/dL the dose can be administered. The Hb influence by a 
transfusion is define in Table 5. Dose Delay, Dose Reduction and Discontinuation Guidelines.  
Revised Section: Section 7.2
1.5.7.
Study Drug Administration: introduced criteria for WBC threshold as 
additional criteria for dose administration
Rationale:
 additional criteria for dose administration 
has been introduced, ie WBC absolute value at the day of the dosing, should note be more than 3 
times WBC measured at baseline. 
Revised Section: Section 7.2. 
1.5.8.
Revised Section: Section 7.2 Dose Titration – clarified that dose titration if 
transfusion reduction is ≤ 50% (previous < 50%) over at least two dose cycles 
(~6 weeks) is allowed.
Rationale:
Clarification as per investigator feedback.
Revised Section: Section 7.2.1.1.
1.5.9.
Dose Titration – clarified that dose titration special request may be allowed for 
subjects who have been dose reduced once, but lost the response to treatment.
Rationale:
It has been clarified that “After safety and efficacy data review, the sponsor may allow dose 
titration following special requests, such as, but not limited to, subjects who have been dose 
reduced once, but lost the response to treatment”.
Revised Section: Section 7.2.1.1.
1.5.10.
Clarified that Dose Delay for AE unrelated to the study drug, as per discretion 
of the Investigator are allowed
Rationale:
Clarification added in order to allow dose delays for safety reasons other than related AE to 
avoid protocol deviations, as per received feedback from investigators. 
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
15
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
Revised Section: Section 7.2.1.2
1.5.11.
Dose Delay, Dose Reduction and Discontinuation Guidelines: introduced 
threshold for Dose adjustments in respect to the WBC counts compared to 
baseline WBC counts
Rationale:
 additional criteria for dose adjustment has 
been introduced, ie fold increase of the WBC absolute value at the day of the dosing, compare to 
the WBC measured at baseline. 
Revised Section: Section 7.2.1.2, Table 5
1.6.
Concomitant Medications
1.6.1.
Removed references for medication leading to treatment discontinuation from 
sections other than Section 8.2 
Rationale:
Medications that will trigger treatment discontinuation are described in the prohibited 
medications section (Section 8.2). For clarity, and consistency references to such medications 
have been removed from other sections.
Revised Sections: Section 8 and Section 8.1.1.
1.6.2.
Anticoagulant therapies used during the study treatment are allowed as long as 
the medications are not used due to a related adverse event (AE) that would 
qualify for treatment discontinuation
Rationale:
Clarified that the use of anticoagulant therapies will trigger treatment discontinuation only if 
such therapies are used due to a related AE that would qualify for treatment discontinuation as 
per Section 11 of the protocol. 
Revised Section: Section 8.2.
1.6.3.
Anagrelide added as prohibited medication
Rationale:
This class of drug-cAMP phosphodiesterase inhibitor, predisposes to prolonged QT interval and 
requires close monitoring with ECG and ECHO. In the β-thalassemia population this poses an 
additional risk of further potential cardiac morbidity [BC Cancer Agency Cancer Drug Manual 
for Anagrelide p 2/7(1st Nov 2015)]. 
Revised Section: Section 8.2.
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
16
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
1.7.
Statistical Section
1.7.1.
Clarification that transfusion received on Dose 1 Day 1 will be counted in the 
baseline transfusion burden.
Rationale:
Clarification added to reflect the modification that a transfusion can be administered on Dose 1 
Day 1. This approach has been presented and reviewed with the SC at the 10 Jun 2016 SC 
meeting.
Revised Sections: Section 9.6.1
1.7.2.
Clarification added to the Other efficacy analyses section that log 
transformation may be applied as appropriate.
Rationale:
The statistical assumption for an analysis of covariance (ANCOVA) method will be validated,
which will allow the statistical methodology to be more complete.
Revised Section: Section 9.6.3
1.7.3.
Clarification to the duration of transfusion burden reduction
Rationale:
Modification added for clarity that “the longest duration will be used if there are multiple 
intervals and the sum of the durations might be summarized if applicable.” This modification 
provides options if multiple intervals occur. 
Revised Section: Section 9.6.3.8
1.7.4.
Bone Mineral Density – clarified that the analysis will be done on the population 
that have at least 2 measurements.
Rationale:
Clarification added to reflect removal of week 24 DXA assessment.
Revised Section: Section 9.6.3.4.
1.7.5.
Clarification to the regression method used in the postbaseline transfusion
events frequency versus placebo
Rationale:
Clarified that the regression method to be used in analyzing the post baseline transfusion event 
frequency will be negative binomial regression, instead of Poisson regression. This will provide 
statistically better options to estimate the variance. 
Revised Section: Section 9.6.3.11
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
17
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
1.7.6.
Interim Analysis (IA) – IA has been removed from the protocol
Rationale:
The interim analysis has been originally implemented in the study to manage the timeline risk of 
the study if subject enrollment was very slow. As of 4 April 2017, 281 subjects have been 
randomized in the study, projected closure of randomizations is currently targeted in Jun 2017, 
which is approximately one year earlier than originally planned end of randomization . Current 
maintenance of high enrollment rates have diminished the purpose of the interim analysis, 
prompting to the decision to not perform the analysis and proceed to final analysis as per the 
study SAP. Subject safety is monitor on ongoing basis by independent DMC, thus removing the 
IA from the protocol, will not impact the already described regular safety monitoring in the 
protocol. 
Revised Sections: Section 9.8 and Protocol Summary.
1.7.7.
Final Analysis – clarified CSR for MAA and Final CSR
Rationale:
With the implementation of the 156-week Post-treatment Follow-up Period, it has been clarified 
that the clinical study report (CSR) for marketing authorization application (MAA) will be 
including treatment-emergent adverse events (TEAEs) reported for 9 weeks post last dose (as per 
the original version of the protocol). A final CSR will be issued at the End of the Trial. 
Revised Sections: Section 9.9.2.1, Section 9.9.2.2, and Protocol Summary.
1.8.
Adverse Events Section
1.8.1.
AE recording after Treatment Discontinuation
Rationale:
, it has been clarified that “AEs that are suspected to be 
related to the IP as well as new malignancies or pre-malignancies regardless of causality (see 
Section 10.5.2) will be recorded by the Investigator until 156 weeks after the last dose of IP.  
Information will be collected as described in Table of Events, Table 3 and Section 6.5.”
Revised Section: Section 10.1
1.8.2.
Created Malignancy reporting subsection
Rationale:
, a malignancy reporting subsection has been created into the 
Adverse Event Section. In this section a description of the malignancy monitoring is provided 
together with information on the reporting period. 
Revised Section: Section 10.5.2
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
18
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
 
 
1.9.
Discontinuations
1.9.1.
Treatment Discontinuation for any new malignancy
Rationale:
, it has been clarified 
that subject should discontinue treatment for any new malignancy.
Revised Section: 11.1
1.10.
Compound Background
1.10.1.
Updated Potential Risks of Human Use section
Rationale:
Updated section based on updated clinical and nonclinical data. 
Revised Section: Section 1.2.1.4
1.11.
Other minor clarification and corrections 
The amendment also includes several other minor clarifications and corrections:
∀
Clarification that re-screening is allowed and clarified timing of the re-screening 
procedures. Re-screening more than one time is allowed.
∀
The terminology Integrated Voice Response System (IVRS)/ Integrated Web Response 
System (IWRS) has been replaced with the term Interactive Response Technology (IRT) 
system. The IRT term encompasses all modalities when accessing the interactive system, 
thus for accuracy the term IRT has been updated throughout the protocol, instead of 
IVRS/IWRS
∀
Updated Potential Risk of Human Use section, as per the updated standard risk language 
for luspatercept (Section 1.2.1.4)
∀
Clarifications on local and central laboratory assessments provided for specific 
parameters in the Table of Events and Procedure sections.
∀
Clarifications for FCBP and males on the periods to be respected in regards to the 
pregnancy (Section 10.4.1 and Section 10.4.2)
∀
Dose Delay Section have been re-worded for clarity (Section 6.2.1 and Section 6.3.1)
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EDMS Doc. Number:
Luspatercept (ACE-536)
Summary of Changes ACE-536-B-THAL-001
Celgene Corporation
Confidential and Proprietary
19
ACE-536-B-THAL-001 Amendment 1 Final: 21 Apr 2017
∀
Clarification in Section 9.6.3.8 Duration of Transfusion Burden Response, to read “The 
duration of the first response…”, since Section 9.6.3.9 Time to response covers the 
description on “first response”, detailed analysis will be described in the SAP.
∀
Additional editorial revisions or minor clarifications
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