A Phase 2a, Randomized, Open-Label Study to Evaluate the Efficacy, Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of ISIS 702843 Administered Subcutaneously to Patients With Non-Transfusion Dependent β-Thalassemia Intermedia
Phase: PHASE2
Conditions: Beta Thalassemia Intermedia
Sponsor: Ionis Pharmaceuticals, Inc.

 
 
A Phase 2a, Randomized, Open-Label Study to Evaluate the Efficacy, Safety, Tolerability, 
Pharmacokinetics and Pharmacodynamics of ISIS 702843 Administered Subcutaneously to 
Patients With Non-Transfusion Dependent β-Thalassemia Intermedia   
 
NCT04059406 
 
22 May 2023 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Ionis.com 

 
 
 
 
 
IONIS PHARMACEUTICALS, INC. 
 
 
ISIS 702843-CS2 
 
A Phase 2a, Randomized, Open-Label Study to Evaluate the 
Efficacy, Safety, Tolerability, Pharmacokinetics and 
Pharmacodynamics of ISIS 702843 Administered Subcutaneously to 
Patients with Non-Transfusion Dependent β-Thalassemia 
Intermedia 
 
Protocol Amendment 2 – 17 May 2021 
 
 
Trial Sponsor:   
Ionis Pharmaceuticals, Inc. 
 
2855 Gazelle Court 
 
Carlsbad, CA  92010 
 
Phone:  760.931.9200 
 
Fax:  760.603.2502 

ISIS 702843-CS2 
CONFIDENTIAL 
Protocol Amendment 2
Protocol 
17 May 2021
 
2 
 
ISIS 702843-CS2 
Protocol Amendment 2 
 
Clinical Phase:  2a 
 
A Phase 2a, Randomized, Open-Label Study to Evaluate the 
Efficacy, Safety, Tolerability, Pharmacokinetics and 
Pharmacodynamics of ISIS 702843 Administered Subcutaneously to 
Patients with Non-Transfusion Dependent β-Thalassemia 
Intermedia 
 
Protocol History: 
Original Protocol:  
9 August 2019 
Amendment 1: 
8 September 2020 
 
 
 
Sponsor: 
Ionis Pharmaceuticals, Inc. 
Carlsbad, CA  92010 
 
 
 
Confidentiality Statement 
This document contains confidential information of Ionis Pharmaceuticals, Inc. that must not be disclosed to anyone 
other than the recipient study staff and members of the independent ethics committee, institutional review board, or 
authorized regulatory agencies.  This information cannot be used for any purpose other than the evaluation or 
conduct of the clinical investigation without the prior written consent of Ionis Pharmaceuticals, Inc. 

ISIS 702843-CS2 
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Protocol 
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Protocol Signature Page 
 
Protocol Number: 
ISIS 702843-CS2 
Protocol Title: 
A Phase 2a, Randomized, Open-Label Study to Evaluate the Efficacy, 
Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of 
ISIS 702843 Administered Subcutaneously to Patients with Non-
Transfusion Dependent β-Thalassemia Intermedia 
Amendment: 
 Protocol Amendment 2 
Date: 
17 May 2021 
 
I hereby acknowledge that I have read and understand the attached clinical protocol, entitled “A 
Phase 2a, Randomized, Open-Label Study to Evaluate the Efficacy, Safety, Tolerability, 
Pharmacokinetics and Pharmacodynamics of ISIS 702843 Administered Subcutaneously to 
Patients with Non-Transfusion Dependent β-Thalassemia Intermedia,” dated 17 May 2021, and 
agree to conduct the study as described herein. 
I agree to comply with the International Conference on Harmonization Tripartite Guideline on 
Good Clinical Practice. 
I agree to ensure that the confidential information contained in this document will not be used for 
any purpose other than the evaluation or conduct of the clinical investigation without the prior 
written consent of Ionis Pharmaceuticals, Inc.  
 
 
 
 
 
Investigator’s Signature 
 
 
 
Investigator’s Name (please print) 
 
Date (DD Month YYYY) 
 

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TABLE OF CONTENTS 
PROTOCOL AMENDMENT .......................................................................................................10 
PROTOCOL SYNOPSIS ..............................................................................................................15 
STUDY DESIGN AND TREATMENT SCHEMA ......................................................................27 
STUDY GLOSSARY ....................................................................................................................28 
1. 
OBJECTIVES AND ENDPOINTS ............................................................................31 
1.1. 
Objectives ...................................................................................................................31 
1.1.1. 
Primary Objective .......................................................................................................31 
1.1.2. 
Secondary Objectives .................................................................................................31 
1.1.3. 
Exploratory Objectives ...............................................................................................31 
1.1.4. 
Safety Objectives ........................................................................................................32 
1.1.5. 
Pharmacokinetic Objectives .......................................................................................32 
1.2. 
Study Endpoints ..........................................................................................................32 
1.2.1. 
Primary Endpoint ........................................................................................................32 
1.2.2. 
Secondary Endpoints ..................................................................................................32 
1.2.3. 
Exploratory Endpoints ................................................................................................33 
1.2.4. 
Safety Endpoints .........................................................................................................35 
1.2.5. 
PK Endpoints ..............................................................................................................35 
2. 
BACKGROUND AND RATIONALE .......................................................................35 
2.1. 
Overview of Disease ...................................................................................................35 
2.2. 
Therapeutic Rationale .................................................................................................36 
2.3. 
ISIS 702843 ................................................................................................................37 
 
 
 
 
2.3.3. 
Preclinical Experience ................................................................................................38 
2.3.4. 
Clinical Experience .....................................................................................................38 
 
 
2.5. 
Benefit-Risk Assessment ............................................................................................39 
2.5.1. 
Benefit Assessment .....................................................................................................39 
2.5.2. 
Risk Assessment .........................................................................................................39 
2.5.3. 
Overall Assessment of Benefit:Risk ...........................................................................40 
2.5.4. 
Additional Risks During the COVID-19 Pandemic ...................................................40 

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3. 
EXPERIMENTAL PLAN ..........................................................................................41 
3.1. 
Study Design ...............................................................................................................41 
3.2. 
Number of Study Centers ...........................................................................................42 
3.3. 
Number of Patients .....................................................................................................42 
3.4. 
Overall Study Duration and Follow-up ......................................................................42 
3.4.1. 
Screening ....................................................................................................................43 
3.4.2. 
Treatment ....................................................................................................................43 
3.4.3. 
Post-Treatment ............................................................................................................44 
3.5. 
End-of-Study ...............................................................................................................44 
3.6. 
Internal Safety Committee ..........................................................................................44 
3.7. 
Dose Adjustments .......................................................................................................44 
3.8. 
Allowances in the Circumstance of a Public Health Emergency ...............................45 
4. 
PATIENT ENROLLMENT ........................................................................................47 
4.1. 
Screening ....................................................................................................................47 
4.2. 
Randomization ............................................................................................................47 
4.3. 
Replacement of Patients .............................................................................................47 
4.4. 
Treatment Assignment ................................................................................................48 
5. 
PATIENT ELIGIBILITY ...........................................................................................48 
5.1. 
Inclusion Criteria ........................................................................................................48 
5.2. 
Exclusion Criteria .......................................................................................................49 
6. 
STUDY PROCEDURES ............................................................................................51 
6.1. 
Study Schedule ...........................................................................................................51 
6.1.1. 
Screening and Baseline ...............................................................................................51 
6.1.2. 
Treatment Period ........................................................................................................52 
6.1.3. 
Post-Treatment Period ................................................................................................53 
6.2. 
Study Assessments......................................................................................................53 
6.2.1. 
Physical Exams and Vital Signs .................................................................................53 
6.2.1.1. 
Leg Ulcers ...................................................................................................................53 
6.2.2. 
Laboratory and Imaging Assessments ........................................................................53 
6.2.2.1. 
ECG ............................................................................................................................54 
6.2.2.2. 
DEXA Scans ...............................................................................................................54 
6.2.2.3. 
Echocardiography .......................................................................................................55 

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6.2.2.4. 
MRI .............................................................................................................................55 
6.2.2.5. 
Ultrasound ...................................................................................................................55 
6.2.3. 
Disease Severity and Quality of Life Measures .........................................................55 
6.2.3.1. 
Use of Chelation .........................................................................................................55 
6.2.3.2. 
Number of Transfusions .............................................................................................55 
6.2.3.3. 
NTDT-PRO©, SF-36, PGIC, ISGA, and FACIT-Fatigue ...........................................55 
6.2.4. 
Functional Status of the Patient Measure ...................................................................56 
6.2.4.1. 
6MWT with Pulse Oximetry ......................................................................................56 
6.3. 
Restriction on the Lifestyle of Patients .......................................................................56 
6.3.1. 
Contraception Requirements ......................................................................................56 
6.3.2. 
Other Requirements ....................................................................................................57 
7. 
STUDY DRUG ...........................................................................................................57 
 
 
7.2. 
Packaging and Labeling ..............................................................................................57 
7.3. 
Study Drug Accountability .........................................................................................57 
8. 
TREATMENT OF PATIENTS ..................................................................................57 
8.1. 
ISIS 702843 Administration .......................................................................................57 
8.2. 
Other Protocol-Required Drugs ..................................................................................58 
8.3. 
Other Protocol-Required Treatment Procedures ........................................................58 
8.4. 
Treatment Precautions ................................................................................................58 
8.5. 
Safety Monitoring Rules .............................................................................................59 
8.5.1. 
Safety Monitoring Rules for Liver Chemistry Tests ..................................................59 
8.5.2. 
Safety Monitoring Rules for Platelet Count Results...................................................60 
8.5.3. 
Safety Monitoring for Minor Bleeding Events ...........................................................60 
8.6. 
Temporary and Permanent Stopping Rules ................................................................60 
8.6.1. 
Temporary Stopping Rules for Hb Results .................................................................61 
8.6.2. 
Temporary Stopping Rules for Thalassemia Intermedia Related Safety 
Concerns/ Morbidities ................................................................................................61 
8.6.3. 
Permanent Stopping Rules for Thalassemia Intermedia Related Safety 
Concerns / Morbidities ...............................................................................................62 
8.6.4. 
Temporary and Permanent Stopping Rules for Liver Chemistry Elevations .............62 
8.6.5. 
Temporary and Permanent Stopping Rules for Renal Function Test Results ............62 
8.6.6. 
Temporary and Permanent Stopping Rules for Platelet Count Results ......................63 

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8.7. 
Adjustment of ISIS 702843 Dose and/or Treatment Schedule ...................................65 
8.8. 
Discontinuation of ISIS 702843 Treatment ................................................................66 
8.9. 
Withdrawal of Patients from the Study Procedures ....................................................67 
8.10. 
Concomitant Therapy and Procedures ........................................................................67 
8.10.1. 
Concomitant Therapy .................................................................................................68 
8.10.2. 
Concomitant Procedures .............................................................................................68 
8.11. 
Treatment Compliance ................................................................................................68 
9. 
SERIOUS AND NON-SERIOUS ADVERSE EVENT REPORTING .....................69 
9.1. 
Sponsor Review of Safety Information ......................................................................69 
9.2. 
Regulatory Requirements ...........................................................................................69 
9.3. 
Definitions ..................................................................................................................69 
9.3.1. 
Adverse Event .............................................................................................................69 
9.3.2. 
Adverse Drug Reaction and Suspected Unexpected Adverse Drug Reaction ............70 
9.3.3. 
Serious Adverse Event (SAE) ....................................................................................70 
9.4. 
Monitoring and Recording Adverse Events ...............................................................71 
9.4.1. 
Serious Adverse Events ..............................................................................................71 
9.4.2. 
Non-Serious Adverse Events ......................................................................................72 
9.4.3. 
Evaluation of Adverse Events (Serious and Non-Serious) .........................................72 
9.4.3.1. 
Relationship to ISIS 702843 .......................................................................................72 
9.4.3.2. 
Severity .......................................................................................................................72 
9.4.3.3. 
Action Taken with ISIS 702843 .................................................................................73 
9.4.3.4. 
Treatment Given for Adverse Event ...........................................................................73 
9.4.3.5. 
Outcome of the Adverse Event ...................................................................................73 
9.4.3.6. 
Follow-up of Adverse Event .......................................................................................74 
9.5. 
Procedures for Handling Special Situations ...............................................................74 
9.5.1. 
Abnormalities of Laboratory Tests .............................................................................74 
9.5.2. 
Prescheduled or Elective Procedures or Routinely Scheduled Treatments ................75 
9.5.3. 
Dosing Errors ..............................................................................................................75 
9.5.4. 
Contraception and Pregnancy .....................................................................................75 
10. 
STATISTICAL CONSIDERATIONS .......................................................................76 
10.1. 
Stratification ...............................................................................................................76 
10.2. 
Sample Size Considerations .......................................................................................76 

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10.3. 
Populations .................................................................................................................77 
10.4. 
Definitions of Baseline ...............................................................................................77 
10.5. 
Interim Analyses .........................................................................................................77 
10.6. 
Planned Methods of Analysis .....................................................................................77 
10.6.1. 
Demographic and Baseline Characteristics ................................................................78 
10.6.2. 
Safety Analysis ...........................................................................................................78 
10.6.3. 
Efficacy Analyses .......................................................................................................78 
10.6.4. 
Pharmacokinetic Analysis ..........................................................................................79 
10.6.5. 
Additional Exploratory Analyses ...............................................................................79 
11. 
INVESTIGATOR’S REGULATORY OBLIGATIONS ...........................................79 
11.1. 
Informed Consent .......................................................................................................79 
11.2. 
Ethical Conduct of the Study ......................................................................................80 
11.3. 
Independent Ethics Committee / Institutional Review Board ....................................80 
11.4. 
Patient Confidentiality ................................................................................................80 
12. 
ADMINISTRATIVE AND LEGAL OBLIGATIONS ..............................................81 
12.1. 
Protocol Amendments ................................................................................................81 
12.2. 
Study Termination ......................................................................................................81 
12.3. 
Study Documentation and Storage .............................................................................81 
12.4. 
Study Monitoring ........................................................................................................82 
12.5. 
Language .....................................................................................................................82 
12.6. 
Compensation for Injury .............................................................................................83 
13. 
REFERENCES ...........................................................................................................84 
14. 
APPENDICES ............................................................................................................85 
APPENDIX A. SCHEDULE OF PROCEDURES .....................................................................86 
APPENDIX B. LIST OF LABORATORY TESTS ....................................................................95 
APPENDIX C. PK SAMPLING SCHEDULE ...........................................................................98 
APPENDIX D. GRADING SCALE FOR ADVERSE EVENTS RELATING TO 
LABORATORY ABNORMALITIES ............................................................100 
APPENDIX E. MEASURES OF QUALITY OF LIFE & FUNCTIONAL STATUS OF 
THE PATIENT ................................................................................................104 
 
 
 

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LIST OF TABLES 
Table 1: 
Planned ISIS 702843 Dosing Information ..................................................................58 
Table 2: 
Actions in Patients with Platelet Count ≤ Lower Limit of Normal (LLN) .................64 
 
 

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PROTOCOL AMENDMENT 
 
Protocol Number: 
ISIS 702843-CS2 
Protocol Title: 
A Phase 2a, Randomized, Open-Label Study to Evaluate the Efficacy, 
Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of 
ISIS 702843 Administered Subcutaneously to Patients with Non-
Transfusion Dependent β-Thalassemia Intermedia 
Amendment Number: 
2 
Amendment Date: 
17 May 2021 
The following modifications to Protocol ISIS 702843-CS2, Amendment 1 have been made. 
Minor changes (not included in the list of changes below) have been made throughout the 
protocol to correct errors and/or to improve the overall clarity of the original protocol, but these 
changes do not impact subject safety, exposure, or the overall study design. 
The following table provides a summary list of major changes to the protocol: 
Protocol Section 
Description of Change 
Rationale 
Section 3.1 Study Design) 
Planned ISIS 702843 dose levels are 
increased as follows:   
• 
Cohort A:  from 30 mg to 120 mg 
• 
Cohort B:  from 50 mg to 120 mg 
• 
Cohort C:  from 80 mg to 120 mg for 
3 consecutive doses, followed by 
160 mg per dose, if dose escalation is 
allowed based on a demonstration of 
adequate safety.  Dose escalation will 
be carried out on an individual patient 
basis, and only after clinical and 
laboratory safety evaluations related to 
the prior dose (scheduled to be 
28 days prior) have been completed, 
and there is an acceptable safety 
profile as determined by the Principal 
Investigator (PI) and the Sponsor 
Medical Monitor, as described in this 
section. 
Safety profiles have been 
acceptable to date, and 
increased dose levels may 
provide additional therapeutic 
benefit. 

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Protocol Section 
Description of Change 
Rationale 
Section 8.1 (ISIS 702843 
Administration) 
Changed the planned dose levels, the 
corresponding volumes to be 
administered, and total dose as shown in 
The higher dose levels 
mentioned above increase the 
volumes to be administered and 
Section 3.1 (Study Design), 
Section 3.3 (Number of 
Patients), and Section 10.2 
(Sample Size 
Considerations) 
The number of evaluable patients is 
decreased from approximately 36 overall 
to approximately 24 overall, with the 
number per cohort changed from 
approximately 12 each to approximately 
12 for Cohorts A and B combined, and 
approximately 12 for Cohort C. 
Twelve (12) patients is 
considered sufficient to 
evaluate each planned dose 
level, and there are now only 2:  
120 mg per 28-day interval 
(Cohorts A and B) and 160 mg 
per 28-day interval (Cohort C, 
if dose escalation is allowed 
based on a demonstration of 
adequate safety). 
Section 8.7 (Adjustment of 
ISIS 702843 Dose and/or 
Treatment Schedule) and 
Section 10.5 (Interim 
Analyses) 
Changed the thresholds for the number of 
patients needed for the interim analyses 
from at least 30 to at least 20 for the first 
interim analysis, and from at least 24 to at 
least 16 for the second interim analysis. 
Decreased both thresholds by 
the same proportion as for the 
overall number of evaluable 
patients (see prior row). 
Section 5 (Patient 
Eligibility) 
Added that the mean of all values obtained 
during the Screening Period is generally 
considered sufficient when making a 
decision regarding eligibility; however, 
the Medical Monitor will also consider 
trends in the data and the significance of 
one or more individual values that are 
outside of acceptable limits when making 
a determination. 
Clarity. 

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Protocol Section 
Description of Change 
Rationale 
Section 5.1 (Inclusion 
Criteria) 
Inclusion Criterion 5 is changed as 
follows:  Mean hemoglobin (Hb) 
acceptable range is widened from 6.0–
10.0 g/dL to 6.0–10.5 g/dL. 
An upper limit of 10.0 g/dL is 
now considered too restrictive. 
Section 5.2 (Exclusion 
Criteria) 
Exclusion Criterion 6 (EC#6) is changed 
as follows:  Platelet count Screening 
laboratory results acceptable range is 
widened from lower limit of normal 
(LLN) – 1,000,000/mm3 to 120,000/mm3 –
1,000,000/mm3. 
Section 5.2 (Exclusion 
Criteria) 
Exclusion Criterion 20 reworded to 
provide clarity regarding human 
immunodeficiency virus (HIV), hepatitis 
C, or hepatitis B infection that is 
exclusionary. 
Clarity. 
Section 5.2 (Exclusion 
Criteria) 
Exclusion Criterion 29 added to provide 
clarity regarding SARS-CoV-2 infection 
that is exclusionary, and to clarify that it is 
acceptable to receive COVID-19 
vaccinations while in this study, including 
in the Screening Period. 
Clarity. 

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Protocol Section 
Description of Change 
Rationale 
Section 8.6.1 (Temporary 
Stopping Rules for Hb 
Results) 
(i) Criterion 2 changed from confirmed Hb 
value ≥ 12.0 g/dL to ≥ 12.5 g/dL, and (ii) 
Criterion 3 changed from confirmed Hb 
increase of ≥ 2.0 g/dL within a 4-week 
period and Hb > 10.0 g/dL, to the same 
except Hb > 10.5 g/dL. 
Both of these increases of 
0.5 g/dL correspond with the 
change to Inclusion Criterion 5 
(IC#5), which is an increase of 
0.5 g/dL to the upper limit of 
mean Hb (from 10.0 to 
10.5 g/dL; see above).  This 
maintains (i) a difference of 
2.0 g/dL between the 
Criterion 2 value and the upper 
limit of mean Hb in IC#5, and 
(ii) no difference between the 
Criterion 3 value and the upper 
limit of mean Hb in IC#5. 
Section 8.6.6 (Temporary 
and Permanent Stopping 
Rules for Platelet Count 
Results) 
A statement is added to clarify that in the 
event of any platelet count 
> 1,000,000/mm3, the utility of 
adjustments to concomitant medications 
(e.g., anti-coagulants) will be determined 
by the PI in consultation with the Medical 
Monitor. 
Clarity. 
Section 8.7 (Adjustment of 
ISIS 702843 Dose and/or 
Treatment Schedule) 
Except for the reference to the second 
interim analysis and within criterion 4, all 
occurrences of Day 365 (Week 53) have 
been changed to Day 281 (Week 41) to 
allow dose adjustments for the stated 
reasons to occur earlier.  Within 
Criterion 4, added Day 281 (Week 41). 
Earlier increases in dose levels 
may provide additional 
therapeutic benefit. 
Section 8.7 (Adjustment of 
ISIS 702843 Dose and/or 
Treatment Schedule) 
Added to Criteria 1-4 the additional dose 
adjustments that are now possible. 
Maximum dose per 28-day 
interval is increased from 
120 mg to 160 mg (see above).  
Section 3.3 (Number of 
Patients) and Section 4.3 
(Replacement of Patients) 
Changed the maximum number of 
replacements from 3 patients per cohort 
(i.e., 9 total) to 3 patients for Cohorts A 
and B combined, and 3 patients for 
Cohort C (i.e., 6 total). 
Three (3) replacements per 
dose level is considered 
sufficient, and there are now 
only two planned:  120 mg per 
28-day interval (Cohorts A and 
B) and 160 mg per 28-day 
interval (Cohort C, if dose 
escalation is allowed based on a 
demonstration of adequate 
safety). 

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Protocol Section 
Description of Change 
Rationale 
Section 3.3 (Number of 
Patients) and Section 4.3 
(Replacement of Patients) 
Decreased the maximum enrollment for 
the study from 45 to 30 patients. 
The number of evaluable 
patients is decreased from 
approximately 36 overall to 
approximately 24 overall (see 
above) and the maximum 
number of replacements is 
decreased from 9 total to 6 total 
(see prior row). 
Section 3.3 (Number of 
Patients) and Section 4.3 
(Replacement of Patients) 
Clarified that the Sponsor may close 
enrollment to one cohort before another, 
and that it is likely that enrollment to 
Cohort B will be closed before enrollment 
to Cohort C. 
The intent is to have 
approximately 12 evaluable 
patients in Cohorts A and B 
combined, and approximately 
12 evaluable patients in 
Cohort C. 
Section 3.3 (Number of 
Patients) and Section 4.3 
(Replacement of Patients) 
Removed the statement that patients will 
not be replaced if the PI, in consultation 
with the Medical Monitor, concludes that 
replacement is not advisable for reasons of 
safety. 
This statement is more 
applicable to a Phase 1 study. 
Section 3.2 (Number of 
Study Centers) 
Changed the list of territories to 
correspond with the centers currently 
planned for this study; deleted Canada and 
added Mediterranean countries. 
Clarity. 
Section 6.2.2 (Laboratory 
and Imaging Assessments) 
Clarified that Investigators may, at their 
discretion, test specific laboratory 
parameters that may be prone to clotting, 
clumping, or hemolysis (e.g., hematology 
samples) at their local laboratory, in 
addition to the required central laboratory 
samples.  Also, clarified that in the event 
of an unreportable platelet count result, 
repeat testing may be conducted at a 
central or local laboratory. 
To clarify the flexibility there is 
regarding the allowance for 
testing at a local laboratory, 
including repeat platelet count 
testing 
Appendix A (Schedule of 
Procedures – Screening 
Period, Treatment Period, 
& Early Termination from 
Treatment (ETFT)) 
Added an “X” in the row for Clinic Visit 
and the column for SV1. 
Correction of an error in 
Amendment 1. 
Appendix A (Schedule of 
Procedures – Screening 
Period, Treatment Period, 
& Early Termination from 
Treatment (ETFT)) 
For Echocardiogram and DEXA scan, 
changed the acceptable timing within the 
Screening Period from SV1 to anytime 
through SV2. 
To provide more flexibility 
with respect to when these 
assessments need to be 
performed to establish 
Baseline. 

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PROTOCOL SYNOPSIS 
Protocol Title 
A Phase 2a, Randomized, Open-Label Study to Evaluate the Efficacy, Safety, 
Tolerability, Pharmacokinetics and Pharmacodynamics of ISIS 702843 
Administered Subcutaneously to Patients with Non-Transfusion Dependent 
β-Thalassemia Intermedia 
Study Phase 
2a 
Indication 
Anemia and Iron overload in patients with Non-Transfusion Dependent 
β-Thalassemia Intermedia 
Primary Objective 
Evaluate the efficacy of antisense inhibitor of TMPRSS6 (ISIS 702843) by 
demonstrating an improvement in hemoglobin (Hb) concentration at Week 27 
of treatment 
Secondary Objectives 
Evaluate the efficacy of ISIS 702843 by demonstrating an improvement in Hb 
concentration at Week 53 of treatment 
Evaluate the efficacy of ISIS 702843 by demonstrating an improvement in 
liver iron concentration (LIC) at Week 53 of treatment 
Exploratory Objectives Evaluate the impact of ISIS 702843 on Ineffective Erythropoiesis (IE):  
• 
Erythroferrone (ERFE); soluble transferrin receptor 1 (sTfR1); 
reticulocyte count; reticulocyte Hb content (CHr); erythropoietin (EPO); 
growth differentiation factor 15 (GDF15); erythroblast count; bone 
marrow iron concentration 
Evaluate the impact of ISIS 702843 on measures of iron overload: 
• 
LIC; spleen iron concentration; serum transferrin saturation (TSAT); 
non-transferrin-bound iron (NTBI); serum ferritin 
Evaluate the efficacy of ISIS 702843 by demonstrating an increase in serum 
hepcidin concentration 
Evaluate the efficacy of ISIS 702843 by demonstrating improvement in 
anemia parameters: 
• Hb; red blood cell (RBC) count; hematocrit; MCV; MCH; MCHC 
Evaluate the impact of ISIS 702843 on hemolysis: 
• 
Haptoglobin; protoporphyrin-IX; bilirubin (indirect); lactate 
dehydrogenase (LDH); peripheral blood smear 
Evaluate the impact of ISIS 702843 on coagulation profile: 
• 
Prothrombin time (PT); international normalized ratio (INR); activated 
partial thromboplastin time (aPTT); antithrombin III; Protein S; Protein C 
Evaluate the impact of ISIS 702843 on disease severity and quality of life 
measures: 
• 
Number of transfusions; chelator usage; non-transfusion dependent 
-thalassemia patient-reported outcomes (NTDT-PRO©); 36-item short 
form survey (SF-36); Patient Global Impression of Change (PGIC); 
Investigator’s Static Global Assessment (ISGA); Functional Assessment 
of Chronic Illness Therapy – Fatigue (FACIT-Fatigue) 

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PROTOCOL SYNOPSIS CONTINUED 
Exploratory Objectives 
Continued 
Evaluate the impact of ISIS 702843 on functional status of the patient: 
• 
6-minute walk test (6MWT) with pulse oximetry 
Safety Objectives 
Evaluate the safety and tolerability of multiple doses of ISIS 702843 in 
patients with β-Thalassemia Intermedia 
Evaluate the impact of multiple doses of ISIS 702843 on the emergence and/or 
progression of recognized complications of β-Thalassemia Intermedia 
PK Objectives 
Evaluate pharmacokinetic (PK) exposure over time and potential 
PK/pharmacodynamic (PD) correlation on relevant biomarkers and efficacy 
outcome measures 
Study Design 
ISIS 702843-CS2 is a multi-center, randomized, open-label study of 
subcutaneously (SC) administered ISIS 702843 in patients with 
non-transfusion dependent β-Thalassemia Intermedia. 
The study will comprise 3 cohorts – Cohorts A, B, and C.  However, upon 
Amendment 2 approval, (i) the dose level for Cohorts A and B will become 
the same at 120 mg ISIS 702843, and (ii) no new patients will be randomized 
to Cohort A.  There will be approximately 12 eligible patients in Cohorts A 
and B combined, and approximately 12 eligible patients in Cohort C, for a 
total of approximately 24 eligible patients overall.  These patients will be 
stratified based on Screening Mean Hb for Eligibility, low (≤ 8.0 g/dL) and 
high (> 8.0 g/dL).  Then patients will be randomized in parallel to Cohort B 
(120 mg ISIS 702843 per dose) or Cohort C (120 mg ISIS 702843 per dose for 
three consecutive doses, followed by 160 mg ISIS 702843 per dose, if dose 
escalation is allowed based on a demonstration of adequate safety). 
Dose escalation to 160 mg ISIS 702843 in Cohort C will be done on an 
individual patient basis, if such escalation is allowed based on the judgment of 
the Principal Investigator (PI), in consultation with the Medical Monitor, 
specifically that there is an acceptable safety profile as described in 
Section 3.1. 
In addition, ISIS 702843 dose adjustments (decreases and increases to the 
proposed maximum clinical dose of 160 mg per 28-day interval) are permitted 
in all cohorts, as described in Section 8.7. 
Each patient will be treated for up to 2 years, receiving up to 27 doses of 
ISIS 702843, with a planned 28-day interval between each dose. 
This is an open-label study.  Nevertheless, to facilitate obtaining objective 
feedback from the patients on their quality of life measures, it is preferable 
that patients not be informed of how their dose compares to the dosing levels 
of other cohorts and individual patients. 

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PROTOCOL SYNOPSIS CONTINUED 
Number of Patients 
The study will enroll approximately 24 evaluable patients overall, with 
approximately 12 evaluable patients in Cohorts A and B combined, and 
approximately 12 evaluable patients in Cohort C.  Patients who terminate early 
from the study may be replaced, with a maximum of 3 replacements for 
Cohorts A and B combined, and with a maximum of 3 replacements for 
Cohort C.  Patients who discontinue after Day 365 (Week 53) will not be 
replaced.  Each additional patient will be assigned to the same cohort and 
stratum (i.e., Hb ≤ 8.0 g/dL, or Hb > 8.0 g/dL) as the patient they are 
replacing.  Before a fit is identified, patients who do not qualify for that 
stratum will still be enrolled in the study, including into that cohort.  
The maximum enrollment for the study will be limited to 30 patients or until 
enrollment is closed by the Sponsor.  The Sponsor may close enrollment to 
one cohort before another; for example, it is likely that enrollment to Cohort B 
will be closed before enrollment to Cohort C because the intent is to have 
approximately 12 evaluable patients in Cohorts A and B combined, and 
approximately 12 evaluable patients in Cohort C. 
Study Population 
The Medical Monitor may be consulted if any questions arise regarding 
Inclusion or Exclusion criteria listed below. 
Inclusion Criteria 
1. Patient must have given written informed consent and be able to comply 
with all study requirements 
2. Aged 18-65 years old, inclusive, at the time of informed consent 
3. Clinical diagnosis of -Thalassemia Intermedia with genotypic 
confirmation of -globin gene mutations including but not limited to 
Hemoglobin E (HbE)/-thalassemia 
4. Patient must be non-transfusion dependent as defined by:  No more than 
8 transfusions in the past 12-month period, and no transfusions in the 
8-week period prior to Day 1 
5. Mean Hb within the range 6.0-10.5 g/dL, inclusive, with this mean based 
on all Hb measurements taken in the Screening Period that are at least 
6 weeks after the most recent transfusion for that patient.  This mean must 
be based on at least 2 Hb measurements. 
6. LIC within the range of 3.0-20.0 mg Fe/g dry weight, inclusive 
7. Chelators will be permitted provided the dose has not been increased for 
at least 2 months prior to Day 1, with LIC > 5.0 mg Fe/g dry weight and 
serum ferritin > 300 ng/mL 
 
 

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PROTOCOL SYNOPSIS CONTINUED 
Study Population 
Continued 
Inclusion Criteria Continued 
8. Females must be non-pregnant and non-lactating, and one of the following: (i) 
surgically sterile (e.g., tubal occlusion, hysterectomy, bilateral salpingectomy, 
bilateral oophorectomy), (ii) postmenopausal (defined as 12 months of 
spontaneous amenorrhea without an alternative medical cause and follicle 
stimulating hormone [FSH] levels in the postmenopausal range for the 
laboratory involved), (iii) abstinent*, or (iv) if engaged in sexual relations and 
of child-bearing potential, the patient must be using a highly effective 
(Section 6.3.1) contraceptive method from the time of signing the informed 
consent until at least 13 weeks after the last dose of ISIS 702843. 
Males must be one of the following:  (i) surgically sterile, (ii) abstinent*, or 
(iii) if engaged in sexual relations with a female of child-bearing potential, the 
patient must be using a highly effective (Section 6.3.1) contraceptive method 
from the time of signing the informed consent until at least 13 weeks after the 
last dose of ISIS 702843. 
* Abstinence is only acceptable as true abstinence, i.e., when this is in line 
with the preferred and usual lifestyle of the patient.  Periodic abstinence 
(e.g., calendar, ovulation, symptothermal, post-ovulation methods), 
declaration of abstinence for the duration of a trial, and withdrawal are not 
acceptable methods of contraception. 
Exclusion Criteria 
1. Genotypic confirmation of either α-globin gene triplication or sickle 
hemoglobin (HbS)/b-thalassemia, as determined by genetic assessment 
of a panel of blood-related disorders 
2. Clinically significant abnormalities in medical history or physical 
examination, which at the discretion of the PI will pose significant 
additional risk to the patient in participating in the study 
3. Clinically significant abnormalities in Screening laboratory values that 
would render a patient unsuitable for inclusion, at the discretion of the 
PI 
4. Current use of iron-chelation therapy if LIC is 3.0–5.0 mg Fe/g dry 
weight, inclusive, or if serum ferritin ≤ 300 ng/mL 
5. Symptomatic splenomegaly, including abdominal pain or organ obstruction, or 
evidence of hypersplenism, such as low white blood cell (WBC) count and/or 
low platelets 
6. Platelet count Screening laboratory results < 120,000/mm3 or 
> 1,000,000/mm3, or any other clinically significant abnormalities in platelet 
count Screening laboratory values that would render a patient unsuitable for 
inclusion 
 
 

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PROTOCOL SYNOPSIS CONTINUED 
Study Population 
Continued 
Exclusion Criteria Continued 
7. Significant concurrent/recent coagulopathy; history of non-traumatic 
significant bleeding; history of immune thrombocytopenic purpura (ITP); 
current use of SC anti-coagulants; history of thrombotic events, including 
stroke or deep vein thrombosis (DVT) 
8. Clinically significant renal dysfunction which at the discretion of the PI will 
pose significant additional risk to the patient in participating in the study 
9. Either of the following confirmed manifestations of renal dysfunction: 
9a.  Estimated glomerular filtration rate (eGFR) < 45 mL/min/1.73 m2, using 
Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) 
equation 
9b.  Proteinuria manifesting as urine protein-to-creatinine ratio (UPCR) 
≥ 0.50 mg/mg 
10. Clinically significant liver function test (LFT) abnormalities at the discretion 
of the PI 
11. Alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) 
> 3.0 × ULN 
12. Historical diagnosis of cirrhosis, or current signs and symptoms of cirrhosis 
13. Fasting blood glucose > 2.0 × ULN 
14. Significant pulmonary hypertension (PHT) defined as tricuspid regurgitation 
> 3.0 meters per second (m/s) on echocardiography and/or requiring treatment 
15. Uncontrolled hypertension (which for this protocol is considered > 140 mm Hg 
systolic or > 90 mm Hg diastolic) 
16. Heart failure class 3 or higher (New York Heart Association, NYHA) 
17. Ejection fraction < 50% by echocardiogram, multigated acquisition (MUGA), 
or cardiac magnetic resonance imaging (MRI) 
18. Patients unable to have MRI performed, for example, because of a pacemaker 
or implantable cardioverter-defibrillator (MRI is being used to measure LIC) 
19. Active infection requiring systemic antiviral or antimicrobial therapy that will 
not be completed prior to Day 1 
20. Active infection with human immunodeficiency virus (HIV), hepatitis C, or 
hepatitis B diagnosed by initial serological testing and confirmed with RNA 
testing, or prior treatment for hepatitis C.  Patients at Screening who test 
positive by serology, but negative by RNA may be allowed in consultation 
with the Sponsor Medical Monitor 
21. Unwillingness to comply with study procedures, including follow-up, as 
specified by this protocol, or unwillingness to cooperate fully with the 
Investigator 
22. Recent introduction of hydroxyurea (within 6 months prior to Day 1) 
 
 

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PROTOCOL SYNOPSIS CONTINUED 
Study Population 
Continued 
Exclusion Criteria Continued 
23. Treatment with or exposure to another investigational drug, biological agent, 
ASO, small interfering ribonucleic acid (siRNA), or device within one month 
of Screening, or 5 half-lives of investigational agent, whichever is longer; or: 
• Treatment with or exposure to sotatercept (ACE-011), 
luspatercept-aamt (Reblozyl®), or ruxolitinib (Jakafi®) within 
4 months of Screening 
• Treatment with or exposure to hematopoietic stimulating agents 
(e.g., EPOs) or any hypoxia-inducible factor prolyl hydroxylase 
inhibitors (HIF-PHIs) (e.g., roxadustat, vadadustat, daprodustat, 
molidustat, desidustat) within 8 weeks of Day 1 
• Prior bone marrow transplant, stem cell transplant, or gene 
therapy 
24. Regular use of alcohol within 6 months prior to Screening [> 7 drinks/wk for 
females, > 14 drinks/wk for males (1 drink = 5 ounces [150 mL] of wine or 
12 ounces [360 mL] of beer or 1.5 ounces [45 mL] of hard liquor)] 
25. Surgery associated with significant blood loss within 4 months of Screening, 
splenectomy within 12 months of Screening, or splenectomy scheduled during 
the Treatment Period 
26. Use of iron supplements, including iron-containing vitamins, within 4 months 
of Screening 
27. Pregnant or lactating 
28. Have any other conditions which, in the opinion of the PI, would make the 
patient unsuitable for inclusion, or could interfere with the patient participating 
in or completing the study 
29. Active infection with the novel severe acute respiratory syndrome coronavirus 
2 (SARS-CoV-2) that causes COVID-19.  (Note:  It is acceptable to receive 
COVID-19 vaccinations while in this study, including in the Screening Period, 
but it is preferred that there is an interval of at least 7-10 days between each 
vaccination and ISIS 702843 dose.) 
 
 

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PROTOCOL SYNOPSIS CONTINUED 
Treatment Groups During the 2-year Treatment Period, each patient will receive up to 27 SC doses of 
ISIS 702843, with a planned 28-day interval between each dose (i.e., Day 1 
[Week 1], Day 29 [Week 5], Day 57 [Week 9], …, Day 729 [Week 105]).  The 
planned total ISIS 702843 dose regimens are shown in the table below.  However, 
ISIS 702843 dose may be adjusted as described in Section 8.7.  Planned dose levels 
are listed in the table below, with the planned dose escalation in Cohort C being on 
an individual patient basis (Section 3.1). 
Planned Dose of ISIS 702843 
# of 
Doses 
Total ISIS 702843 
Cohort A:  30 mg / 
 
ISIS 702843 for at least 
1 dose (because all 
Cohort A patients are 
randomized before 
Amendment 2 approval); 
then: 
120 mg / 
 
ISIS 702843 
27 
3,150 mg (or less, 
depending on the 
number of doses 
before Amendment 2 
approval) 
Cohort B:  120 mg / 
 
ISIS 702843 
27 
3,240 mg (less for 
patients randomized 
before Amendment 2 
approval) 
Cohort C:  120 mg / 
 
ISIS 702843 for 3 
consecutive doses, then 
160 mg / 
 
ISIS 702843 if dose 
escalation is allowed based 
on a demonstration of 
adequate safety 
27 
4,200 mg (less for 
patients randomized 
before Amendment 2 
approval) 
 
Study Drug Dosage 
and 
Administration 
The Sponsor will provide ISIS 702843 
 
Unless the allowances in the circumstance of a public health emergency apply 
(Section 3.8), through Day 365 (Week 53) all doses will be administered at the 
clinic, either by Study Center staff or by the trained patient/caregiver under the 
observation of Study Center staff.  Self-administration at home is allowed after Day 
365 (Week 53) – earlier if Section 3.8 applies – and after appropriate training of 
patient/caregiver. 
All doses will be administered 
 SC injection(s) in the abdomen, thigh, or 
outer area of the upper arm (Section 8.1). 
 
 

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PROTOCOL SYNOPSIS CONTINUED 
Rationale for Dose 
and Schedule of 
Administration 
There are multiple reasons for the study duration of 2 years.  This duration 
(i) allows assessment of long-term efficacy and safety, (ii) provides further 
guidance on dosing and monitoring for subsequent development, (iii) allows 
evaluation of durability of response, and (iv) permits detection of potential chronic 
or delayed safety signals. 
 
 

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PROTOCOL SYNOPSIS CONTINUED 
Adjustment of 
Dose and/or 
Treatment 
Schedule 
Treatment schedule adjustments and dose pauses will be permitted according to 
predefined criteria (see Section 8.7). 
Two (2) interim analyses are planned.  The first interim analysis is planned to occur 
when at least 20 patients have completed evaluations associated with Day 183 
(Week 27).  The second interim analysis is planned to occur when at least 
16 patients have completed evaluations associated with Day 365 (Week 53).  Based 
on these and/or other analysis(es), ISIS 702843 dose adjustments in addition to the 
dose escalation to 160 mg planned in Cohort C (Section 3.1) will be permitted 
based on prespecified criteria and if the data support such a change providing 
additional therapeutic benefit or safety to the patient(s).  These adjustments may be 
applicable to: 
• 
An entire cohort, but only after the first interim analysis 
• 
An individual patient, but only after that individual has completed PK and PD 
evaluations associated with Day 365 (Week 53) 
Earlier adjustment(s) for an individual patient may occur if it is deemed necessary, 
and the PI should discuss these proposed adjustment(s) with the Medical Monitor 
prior to implementation. 
Maximum ISIS 702843 dose will not exceed 160 mg per administration, with a 
planned 28-day interval between each dose. 
Standard-of-care interventions, including transfusion, introduction of iron chelation 
therapy, and adjustment of chelator dose or formulation, will be permitted, at the 
discretion of the PI.  For example, if serum ferritin decreases to the extent that over-
chelation is a concern, then it is expected that the PI will consider reducing the 
chelator dose, as appropriate, before consideration is given to adjusting the 
ISIS 702843 dose. 
Study Visit 
Schedule and 
Procedures 
Detailed information regarding the study procedures is outlined in Appendix A 
(Schedule of Procedures).  Appendix B presents a list of laboratory tests required 
for the study. 
Blood and urine samples will be collected regularly throughout the study for 
efficacy, safety, PK, and PD analyses. 
MRI evaluations will be performed to monitor LIC, spleen iron concentration, and, 
if feasible, bone marrow iron concentration.  An Iron Metabolism Panel comprising 
serum biomarkers of iron loading (TSAT, NTBI, ferritin) will complement the MRI 
assessments, and also includes a key PD biomarker, hepcidin. 
An Endocrine Panel of serum biomarkers will be evaluated to monitor for iron-
related endocrinopathies (diabetes, hypogonadism, hypothyroidism) 
A panel of serum biomarkers will be analyzed to monitor IE.  Biomarkers of 
hemolysis will also be assessed. 
 
 

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PROTOCOL SYNOPSIS CONTINUED 
Study Visit 
Schedule and 
Procedures 
Continued 
The safety of ISIS 702843 will be monitored in an ongoing fashion throughout the 
study via AE reporting, routine clinical assessments, blood testing, and urine 
testing.  In addition, spleen size and volume, and liver size and volume will be 
monitored. 
The length of each patient’s participation in the study is approximately 29 months 
that includes an approximately 2-month Screening Period, a 24-month Treatment 
Period, and a 3-month Post-Treatment Period (PTP). 
Patients who discontinue from ISIS 702843 treatment and agree to remain in the 
study will attend the following clinic visits:  Early Termination from Treatment 
(ETFT), PTP Visit 1, PTP Visit 2, and PTP Last Visit.  If the patient is unable or 
unwilling to participate in all of these visits, the PI should determine the follow-up 
procedures the patient would agree to complete.  Every effort should be made to 
complete the ETFT procedures and observations at the time of withdrawal. 
Primary Endpoint Proportion of patients who have a ≥ 1.0 g/dL increase from Baseline in Hb, 
comparing the 3 cohorts at Week 27 of treatment. 
Secondary 
Endpoints 
Proportion of patients who have a ≥ 1.5 g/dL increase from Baseline in Hb, 
comparing the 3 cohorts at Week 53 of treatment. 
Proportion of patients who have a ≥ 1.0 mg Fe/g dry weight decrease from Baseline 
in LIC, comparing the 3 cohorts at Week 53 of treatment. 
Exploratory 
Endpoints  
Impact of ISIS 702843 on IE: 
• 
Mean change from Baseline in plasma erythroferrone concentration, 
comparing the 3 cohorts over time 
• 
Mean change from Baseline in plasma sTfR1 concentration, comparing the 
3 cohorts over time 
• 
Mean change from Baseline in reticulocyte count, comparing the 3 cohorts 
over time 
• 
Mean change from Baseline in CHr, comparing the 3 cohorts over time 
• 
Mean change from Baseline in plasma EPO concentration, comparing the 
3 cohorts over time 
• 
Mean change from Baseline in plasma GDF15 concentration, comparing the 
3 cohorts over time 
• 
Mean change from Baseline in erythroblast count, comparing the 3 cohorts 
over time 
• 
Mean change from Baseline in bone marrow iron concentration, comparing the 
3 cohorts over time 

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PROTOCOL SYNOPSIS CONTINUED 
Exploratory 
Endpoints 
Continued 
Impact of ISIS 702843 on measures of iron overload: 
• 
Mean change from Baseline in LIC, comparing the 3 cohorts over time 
• 
Mean change from Baseline in spleen iron concentration, comparing the 
3 cohorts over time 
• 
Mean change from Baseline in TSAT, comparing the 3 cohorts over time 
• 
Mean change from Baseline in NTBI, comparing the 3 cohorts over time 
• 
Mean change from Baseline in serum ferritin, comparing the 3 cohorts over 
time 
• 
Mean change from Baseline in chelator usage, comparing the 3 cohorts over 
time 
• 
Mean change from Baseline in hepcidin, comparing the 3 cohorts over time 
Impact of ISIS 702843 on measures of anemia: 
• 
Mean change from Baseline in Hb, comparing the 3 cohorts over time 
• 
Mean change from Baseline in RBC count, comparing the 3 cohorts over time 
• 
Mean change from Baseline in hematocrit, comparing the 3 cohorts over time 
• 
Mean change from Baseline in mean corpuscular volume (MCV), comparing 
the 3 cohorts over time 
• 
Mean change from Baseline in mean corpuscular Hb, amount (MCH), 
comparing the 3 cohorts over time 
• 
Mean change from Baseline in mean corpuscular Hb concentration (MCHC), 
comparing the 3 cohorts over time 
Impact of ISIS 702843 on hemolysis: 
• 
Mean change from Baseline in plasma haptoglobin, comparing the 3 cohorts 
over time 
• 
Mean change from Baseline in plasma protoporphyrin-IX, comparing the 
3 cohorts over time 
• 
Mean change from Baseline in plasma bilirubin (indirect), comparing the 
3 cohorts over time 
• 
Mean change from Baseline in plasma LDH, comparing the 3 cohorts over 
time 
• 
Evaluation of peripheral blood smears, comparing the 3 cohorts over time 
Impact of ISIS 702843 on coagulation profile: 
• 
Mean change from Baseline in PT, comparing the 3 cohorts over time 
• 
Mean change from Baseline in INR, comparing the 3 cohorts over time 
• 
Mean change from Baseline in aPTT, comparing the 3 cohorts over time 
• 
Mean change from Baseline in antithrombin III, comparing the 3 cohorts over 
time 
• 
Mean change from Baseline in Protein S, comparing the 3 cohorts over time 
• 
Mean change from Baseline in Protein C, comparing the 3 cohorts over time 

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PROTOCOL SYNOPSIS CONTINUED 
Exploratory 
Endpoints 
Continued 
Impact of ISIS 702843 on disease severity and quality of life measures: 
• 
Change in the number of transfusions, comparing the 3 cohorts over time 
• 
Change in chelator usage, comparing the 3 cohorts over time 
• 
Mean change from Baseline in NTDT-PRO©, comparing the 3 cohorts over 
time 
• 
Mean change from Baseline in SF-36, comparing the 3 cohorts over time 
• 
Mean change from Baseline in PGIC, comparing the 3 cohorts over time 
• 
Mean change from Baseline in ISGA, comparing the 3 cohorts over time 
• 
Mean change from Baseline in FACIT-Fatigue, comparing the 3 cohorts over 
time 
Impact of ISIS 702843 on functional status of the patient: 
• 
Mean change from Baseline in 6MWT, comparing the 3 cohorts over time 
Safety Endpoints 
Adverse events (AEs), vital signs, clinical laboratory tests (serum chemistry, 
hematology, urinalysis, coagulation panel, thyroid panel), electrocardiogram 
(ECG). 
Measures of extramedullary hematopoiesis, liver function, splenomegaly, 
osteoporosis, diabetes, pulmonary hypertension, and leg ulcers. 
PK Endpoints 
A PK profile (including pre-dose sampling) over a 6-hour period will be collected 
at Day 1 (Week 1).  Two (2) samples – pre-dose and 3-hour post-dose – will be 
evaluated at Day 197 (Week 29).  Trough levels will be evaluated just prior to 
each dose through Day 169 (Week 25), as well as on a more limited basis 
throughout the rest of the Treatment Period.  One (1) sample will be evaluated on 
Day 183 (Week 27); there is no dose at this visit.  In the Post-Treatment Period, 
1 sample at each of the 3 planned visits will be evaluated. 
Statistical 
Considerations 
There is no statistical rationale for the selected sample size of the study dose 
treatment cohorts.  The sample size was based on prior experience to ensure that 
the safety, tolerability, PK, and PD of ISIS 702843 will be adequately assessed 
while minimizing unnecessary patient exposure. 
Eligible patients will be stratified based on Screening Mean Hb for Eligibility, low 
(≤ 8.0 g/dL) and high (> 8.0 g/dL), and randomized in parallel to Cohort B or C.  
No patients will be randomized to Cohort A after Amendment 2 approval. 
Two (2) interim analyses are planned: 
• 
The first interim analysis is planned to occur when at least 20 patients have 
completed evaluations associated with Day 183 (Week 27) 
• 
The second interim analysis is planned to occur when at least 16 patients have 
completed evaluations associated with Day 365 (Week 53) 
Sponsor 
Ionis Pharmaceuticals, Inc. 
 
 

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STUDY DESIGN AND TREATMENT SCHEMA 
 
 
 
TREATMENT PERIOD 
• Stratify eligible patients based on Screening Mean Hb 
for Eligibility, low (≤ 8.0 g/dL) and high (> 8.0 g/dL) 
• Randomize in parallel to Cohort B or C.  (No patients 
will be randomized to Cohort A after Amendment 2 
approval.) 
• Every 4 weeks administration of ISIS 702843, Weeks 
1-105 
• Self-administration is allowed after Week 53 – earlier if 
Section 3.8 applies – and training 
• Modify dose and/or dose frequency, as needed, based 
on safety monitoring rules 
• Safety & efficacy measurements obtained at regular 
intervals 
• First interim analysis based on evaluations through 
Day 183 (Week 27) 
• Second interim analysis based on evaluations through 
Day 365 (Week 53) 
EARLY TERMINATION FROM 
TREATMENT (ETFT) 
• Patients who discontinue ISIS 702843 
treatment and agree to remain in the 
study will attend the following clinic 
visits: ETFT, PTP Visit 1, PTP Visit 2, 
and PTP Last Visit. If patient is unable 
or unwilling to participate in all of these 
visits, the PI should determine the 
follow-up procedures the patient would 
agree to complete. 
• Every effort should be made to complete 
the ETFT study procedures and 
observations at the time of withdrawal 
SCREENING 
Weeks -9 to -1 
POST-TREATMENT PERIOD (PTP) 
• Three (3) assessments, spanning 13 weeks after last 
dose 
END-OF-STUDY PROCEDURES 
•
PTP Last Visit or ETFT 

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STUDY GLOSSARY 
Abbreviation 
Definition 
2′-MOE 
2′-O-(2-methoxyethyl) 
6MWT 
6-minute walk test 
ADA 
anti-drug antibodies 
AE 
adverse event 
ALP 
alkaline phosphatase 
ALT 
alanine aminotransferase (formerly referred to as serum glutamic pyruvic 
transaminase [SGPT]) 
ANA 
antinuclear antibody 
aPTT 
activated partial thromboplastin time 
ASO 
antisense oligonucleotide 
AST 
aspartate aminotransferase (formerly referred to as serum glutamic 
oxaloacetic transaminase [SGOT]) 
βhCG 
beta-subunit of human chorionic gonadotropin (pregnancy test) 
BP 
blood pressure 
BUN 
blood urea nitrogen 
CBC 
complete blood count 
CHr 
reticulocyte hemoglobin content 
CKD-EPI 
Chronic Kidney Disease Epidemiology Collaboration 
CMV 
Cytomegalovirus 
CRF 
case report form 
CRNMB 
clinically relevant non-major bleeding 
CTCAE 
Common Terminology Criteria for Adverse Events  
DEXA 
dual energy X-ray absorptiometry 
DVT 
deep vein thrombosis 
EBV 
Epstein-Barr virus 
EC 
Ethics Committee 
ECG 
electrocardiogram 
eCRF 
electronic Case Report Form 
EDC 
electronic data capture 
eGFR 
estimated glomerular filtration rate 
EPO 
erythropoietin 
ETFT 
early termination from treatment 
FACIT 
Functional Assessment of Chronic Illness Therapy 
FAS 
Full Analysis Set 
FBS 
fasting blood sugar 
Fe/g 
iron (Fe) per gram of dry weight of liver 
FSH 
follicle-stimulating hormone 
GalNAc 
N-acetyl galactosamine 
GCP 
Good Clinical Practice 
GDF15 
growth differentiation factor 15 
GGT 
gamma-glutamyltransferase 
HAV 
hepatitis A virus 
Hb 
hemoglobin 

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Abbreviation 
Definition 
HbE 
hemoglobin E 
HbS 
sickle hemoglobin 
HBsAg 
hepatitis B surface antigen 
HCV 
hepatitis C virus 
HIF-PHI 
hypoxia-inducible factor prolyl hydroxylase inhibitor 
HIV 
human immunodeficiency virus 
HR 
heart rate 
ICH 
International Conference on Harmonization 
IE 
ineffective erythropoiesis 
IgG 
immunoglobulin G 
IgM 
immunoglobulin M 
INR 
international normalized ratio 
IRB 
Institutional Review Board 
IRT 
Interactive Response Technology 
ISGA 
Investigator’s Static Global Assessment 
ISIS 702843 
antisense inhibitor of TMPRSS6 
ITP 
immune thrombocytopenic purpura 
LDH 
lactate dehydrogenase 
LFT 
liver function test 
LH 
luteinizing hormone 
LIC 
liver iron concentration 
LLN 
lower limit of normal 
m2 
square meter 
MB 
major bleeding 
MCH 
mean corpuscular hemoglobin (amount) 
MCHC 
mean corpuscular hemoglobin concentration 
MCV 
mean corpuscular volume 
MedDRATM 
Medical Dictionary for Regulatory Activities  
mm3 
cubic millimeter 
mm Hg 
millimeters of mercury 
MRI 
magnetic resonance imaging 
mRNA 
messenger ribonucleic acid 
m/s 
meters per second 
MUGA 
multigated acquisition 
NCS 
not clinically significant 
NOAEL 
no-observed-adverse-effect-level 
NTBI 
non-transferrin-bound iron 
NTDT 
non-transfusion dependent thalassemia 
on study 
The patient is ‘on study’ from signing of the informed consent until their 
last study visit 
PD 
pharmacodynamic(s) 
PGIC 
Patient Global Impression of Change 
PHT 
pulmonary hypertension 
PI 
Principal Investigator 

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Abbreviation 
Definition 
PK 
pharmacokinetic(s) 
PRO 
patient-reported outcome(s) 
PT 
prothrombin time 
PTP 
post-treatment period 
RBC 
red blood cell(s) 
RDW 
red cell distribution width 
RNase H1 
an ubiquitous endonuclease that specifically hydrolyzes the RNA strand in 
RNA/DNA hybrids 
SAE 
serious adverse event 
SAP 
Statistical Analysis Plan 
SC 
subcutaneous(ly) 
siRNA 
small interfering ribonucleic acid 
sTfR1 
soluble transferrin receptor 1 
Study Day 1 
defined as the first day ISIS 702843 is administered to the patient 
Study Drug 
ISIS 702843 (there is no placebo in this study) 
SUSAR 
suspected unexpected serious adverse reaction 
SV 
Screening Visit 
TEAE 
treatment-emergent adverse event 
TMPRSS6 
transmembrane protease, serine 6 
TSAT 
transferrin saturation 
TSH 
thyroid-stimulating hormone 
ULN 
upper limit of normal 
UPCR 
urine protein-to-creatinine ratio 
WBC 
white blood cell 
 
 

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1. 
OBJECTIVES AND ENDPOINTS 
1.1. 
Objectives 
1.1.1. 
Primary Objective 
Evaluate the efficacy of antisense inhibitor of TMPRSS6 (ISIS 702843) by demonstrating an 
improvement in hemoglobin (Hb) concentration at Week 27 of treatment. 
1.1.2. 
Secondary Objectives 
Evaluate the efficacy of ISIS 702843 by demonstrating an improvement in Hb concentration at 
Week 53 of treatment. 
Evaluate the efficacy of ISIS 702843 by demonstrating an improvement in liver iron 
concentration (LIC) at Week 53 of treatment. 
1.1.3. 
Exploratory Objectives 
Evaluate the impact of ISIS 702843 on Ineffective Erythropoiesis (IE): 
• Erythroferrone (ERFE); soluble transferrin receptor 1 (sTfR1); reticulocyte count; 
reticulocyte Hb content (CHr); erythropoietin (EPO); growth differentiation factor 15 
(GDF15); erythroblast count; bone marrow iron concentration 
Evaluate the impact of ISIS 702843 on measures of iron overload: 
• LIC; spleen iron concentration; serum transferrin saturation (TSAT); non-transferrin-
bound iron (NTBI); serum ferritin 
Evaluate the efficacy of ISIS 702843 by demonstrating an increase in serum hepcidin 
concentration. 
Evaluate the efficacy of ISIS 702843 by demonstrating improvement in anemia parameters: 
• Hb; RBC count; hematocrit; MCV; MCH; MCHC 
Evaluate the impact of ISIS 702843 on hemolysis: 
• Haptoglobin; protoporphyrin-IX; bilirubin (indirect); lactate dehydrogenase (LDH); 
peripheral blood smear 
Evaluate the impact of ISIS 702843 on coagulation profile: 
• Prothrombin time (PT); international normalized ratio (INR); activated partial 
thromboplastin time (aPTT); antithrombin III; Protein S; Protein C 
Evaluate the impact of ISIS 702843 on disease severity and quality of life measures: 
• Number of transfusions; chelator usage; non-transfusion dependent -thalassemia 
patient-reported outcomes (NTDT-PRO©); 36-item short form survey (SF-36); Patient 
Global Impression of Change (PGIC); Investigator’s Static Global Assessment 
(ISGA); Functional Assessment of Chronic Illness Therapy – Fatigue (FACIT-
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Evaluate the impact of ISIS 702843 on functional status of the patient: 
• 6-minute walk test (6MWT) with pulse oximetry 
1.1.4. 
Safety Objectives 
Evaluate the safety and tolerability of multiple doses of ISIS 702843 in patients with 
β-Thalassemia Intermedia. 
Evaluate the impact of multiple doses of ISIS 702843 on the emergence and/or progression of 
recognized complications of β-Thalassemia Intermedia. 
1.1.5. 
Pharmacokinetic Objectives 
Evaluate pharmacokinetic (PK) exposure over time and potential PK / pharmacodynamic (PD) 
correlation on relevant biomarkers and efficacy outcome measures. 
1.2. 
Study Endpoints 
1.2.1. 
Primary Endpoint 
Proportion of patients who have a ≥ 1.0 g/dL increase from Baseline in Hb, comparing the 
3 cohorts at Week 27 of treatment. 
• Baseline Hb for Analysis is the mean of all Hb measurements taken in the Screening 
Period and Day 1, pre-dose.  Each measurement used for the calculation of Baseline 
must be taken at least 6 weeks after the most recent transfusion for that patient.  
Baseline must be based on at least 2 Hb measurements. 
• The value to use for Week 27 of treatment is the mean of the 2 Hb measurements 
intended to be taken at Day 169 (Week 25) and Day 183 (Week 27); if one of these 
measurements is missing, then the other measurement will be assigned as the value to 
use for Week 27 of treatment.  For a Hb measurement to be usable for the 
determination of the value to use for Week 27 of treatment, the sampling must occur 
at least 6 weeks after the most recent transfusion for that patient. 
1.2.2. 
Secondary Endpoints 
Proportion of patients who have a ≥ 1.5 g/dL increase from Baseline in Hb, comparing the 
3 cohorts at Week 53 of treatment. 
• Baseline Hb for Analysis is as defined above for the Primary Endpoint 
• The value to use for Week 53 of treatment is the mean of the 2 Hb measurements 
intended to be taken at Day 309 (Week 45) and Day 365 (Week 53); if one of these 
measurements is missing, then the other measurement will be assigned as the value to 
use for Week 53 of treatment.  For a Hb measurement to be usable for the 
determination of the value to use for Week 53 of treatment, the sampling must occur 
at least 6 weeks after the most recent transfusion for that patient. 

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Proportion of patients who have a ≥ 1.0 mg Fe/g dry weight decrease from Baseline in LIC, 
comparing the 3 cohorts at Week 53 of treatment. 
• Baseline LIC is the LIC measurement taken during the Screening Period 
• The Week 53 value is the LIC measurement intended to be taken at Day 365 
(Week 53) 
1.2.3. 
Exploratory Endpoints 
Impact of ISIS 702843 on IE: 
• Mean change from Baseline in plasma erythroferrone concentration, comparing the 
3 cohorts over time 
• Mean change from Baseline in plasma sTfR1 concentration, comparing the 3 cohorts 
over time 
• Mean change from Baseline in reticulocyte count, comparing the 3 cohorts over time 
• Mean change from Baseline in CHr, comparing the 3 cohorts over time 
• Mean change from Baseline in plasma EPO concentration, comparing the 3 cohorts 
over time 
• Mean change from Baseline in plasma GDF15 concentration, comparing the 3 cohorts 
over time 
• Mean change from Baseline in erythroblast count, comparing the 3 cohorts over time 
• Mean change from Baseline in bone marrow iron concentration, comparing the 
3 cohorts over time 
Impact of ISIS 702843 on measures of iron overload: 
• Mean change from Baseline in LIC, comparing the 3 cohorts over time 
• Mean change from Baseline in spleen iron concentration, comparing the 3 cohorts 
over time 
• Mean change from Baseline in TSAT, comparing the 3 cohorts over time 
• Mean change from Baseline in NTBI, comparing the 3 cohorts over time 
• Mean change from Baseline in serum ferritin, comparing the 3 cohorts over time 
• Mean change from Baseline in chelator usage, comparing the 3 cohorts over time 
• Mean change from Baseline in hepcidin, comparing the 3 cohorts over time 
Impact of ISIS 702843 on measures of anemia: 
• Mean change from Baseline in Hb, comparing the 3 cohorts over time 
• Mean change from Baseline in RBC count, comparing the 3 cohorts over time 
• Mean change from Baseline in hematocrit, comparing the 3 cohorts over time 

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• Mean change from Baseline in mean corpuscular volume (MCV), comparing the 
3 cohorts over time 
• Mean change from Baseline in mean corpuscular Hb, amount (MCH), comparing the 
3 cohorts over time 
• Mean change from Baseline in mean corpuscular Hb concentration (MCHC), 
comparing the 3 cohorts over time 
Impact of ISIS 702843 on hemolysis: 
• Mean change from Baseline in plasma haptoglobin, comparing the 3 cohorts over 
time 
• Mean change from Baseline in plasma protoporphyrin-IX, comparing the 3 cohorts 
over time 
• Mean change from Baseline in plasma bilirubin (indirect), comparing the 3 cohorts 
over time 
• Mean change from Baseline in plasma LDH, comparing the 3 cohorts over time 
• Evaluation of peripheral blood smears, comparing the 3 cohorts over time 
Impact of ISIS 702843 on coagulation profile: 
• Mean change from Baseline in PT, comparing the 3 cohorts over time 
• Mean change from Baseline in INR, comparing the 3 cohorts over time 
• Mean change from Baseline in aPTT, comparing the 3 cohorts over time 
• Mean change from Baseline in antithrombin III, comparing the 3 cohorts over time 
• Mean change from Baseline in Protein S, comparing the 3 cohorts over time 
• Mean change from Baseline in Protein C, comparing the 3 cohorts over time 
Impact of ISIS 702843 on disease severity and quality of life measures: 
• Change in the number of transfusions, comparing the 3 cohorts over time 
• Change in chelator usage, comparing the 3 cohorts over time 
• Mean change from Baseline in NTDT-PRO©, comparing the 3 cohorts over time 
• Mean change from Baseline in SF-36, comparing the 3 cohorts over time 
• Mean change from Baseline in PGIC, comparing the 3 cohorts over time 
• Mean change from Baseline in ISGA, comparing the 3 cohorts over time 
• Mean change from Baseline in FACIT-Fatigue, comparing the 3 cohorts over time 
Impact of ISIS 702843 on functional status of the patient: 
• Mean change from Baseline in 6MWT, comparing the 3 cohorts over time 

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1.2.4. 
Safety Endpoints 
Adverse events (AEs), vital signs, clinical laboratory tests (serum chemistry, hematology, 
urinalysis, coagulation panel, thyroid panel), electrocardiogram (ECG). 
Measures of extramedullary hematopoiesis, liver function, splenomegaly, osteoporosis, diabetes, 
pulmonary hypertension (PHT), and leg ulcers. 
1.2.5. 
PK Endpoints 
A PK profile (including pre-dose sampling) over a 6-hour period will be collected at Day 1 
(Week 1).  Two (2) samples – pre-dose and 3-hour post-dose – will be evaluated at Day 197 
(Week 29).  Trough levels will be evaluated just prior to each dose through Day 169 (Week 25), 
as well as on a more limited basis throughout the rest of the Treatment Period.  One (1) sample 
will be evaluated on Day 183 (Week 27); there is no dose at this visit.  In the Post-Treatment 
Period (PTP), 1 sample at each of the 3 planned visits will be evaluated. 
2. 
BACKGROUND AND RATIONALE 
2.1. 
Overview of Disease 
-Thalassemia is an autosomal recessive disorder characterized by abnormal -globin 
production.  The clinical presentation is highly variable with mild to severe hypochromic 
microcytic anemia, progressive splenomegaly, and growth retardation.  With time, secondary 
iron overload may evolve with a multitude of symptoms related to excessive tissue iron 
deposition including liver disease, osteoporosis, diabetes, hypothyroidism, and hypogonadism.  
Further complications include PHT, heart failure, thrombotic events (e.g., deep vein thrombosis 
[DVT], stroke), and leg ulcers.  Erythroid marrow expansion can cause extramedullary 
hematopoiesis with hepatosplenomegaly and extramedullary haematopoietic pseudotumors.  
Excessive hemolysis can result in gallstones. 
While thalassemia is an ultra-rare disorder in the USA, it is most common among people of 
Italian, Greek, Middle Eastern, South Asian, and North African descent.  Males and females 
have similar predilection for the disease.  
β-Thalassemia is characterized by IE, anemia, and hemolysis.  The etiology of the anemia is 
multifactorial.  Adult Hb comprises 2 -globin and 2 -globin (22) chains.  In -Thalassemia, 
a quantitative deficiency in -globin results in impaired Hb production with subsequent anemia.  
Furthermore, due to -globin deficiency, there is an -globin chain excess which aggregate to 
form toxic hemichromes.  These hemichromes mediate terminal erythroid maturation arrest and 
this impaired red cell differentiation further exacerbates the underlying anemia phenotype.  In 
addition, hemichromes along with excessive reactive oxygen species destabilize the red cell 
membrane rendering them susceptible to hemolysis. 
The IE and anemia result in massive expansion of the red cell precursor pool with high demand 
for iron to support the ineffective production of red cells.  To meet this demand, massive 
intestinal iron hyperabsorption occurs due to suppression of hepcidin, a 25-amino acid 
hepatic-derived peptide hormone central to iron homeostasis.  

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Hepcidin serves to limit plasma iron mobilization by binding to ferroportin thereby mediating its 
internalization and subsequent degradation.  Ferroportin is the sole exporter of iron from cells 
under physiological conditions, and is expressed predominately in the liver, intestinal enterocyte 
(basal surface), and macrophages.  In the presence of iron overload, hepcidin is induced with 
subsequent destruction of ferroportin thereby suppressing intestinal iron uptake.  -Thalassemia, 
however, is characterized by aberrant suppression of hepcidin despite iron overload (due to 
excess production of erythroferrone), and hence ferroportin cell surface expression is maintained 
resulting in continual intestinal iron hyperabsorption and tissue iron overload. 
The distinction between the various phenotypes of β-Thalassemia relies primarily on the clinical 
severity of the disease.  Originally β-Thalassemia intermedia was used to describe patients who 
had clinical manifestations that were too severe to be termed β-Thalassemia minor, yet were too 
mild to be termed β-Thalassemia Major (Sturgeon et al. 1955).  Today, the degree of transfusion 
dependency further helps differentiate Intermedia from Major, with Intermedia usually not being 
transfusion dependent (NTDT), and Major characterized by transfusion dependency (TDT).  
Patients with β-Thalassemia intermedia usually present in later childhood or even adulthood, 
with mild to moderate anemia and a Hb between 7 and 10 g/dL, which typically is sustainable 
without the need for regular transfusion therapy. 
Multiple modalities of intervention are utilized in the management of -Thalassemia, depending 
on the severity of the condition, including blood transfusions, iron chelation therapy, 
splenectomy, hydroxyurea, and other supportive interventions.  Despite numerous therapies, 
treatments do not alter the progressive course of the disease and there remains a substantial 
unmet medical need for better disease modifying therapies for -Thalassemia. 
2.2. 
Therapeutic Rationale 
Transmembrane protease, serine 6 (TMPRSS6) is a transmembrane serine protease 
predominantly expressed in liver cells and is a key negative regulator of hepcidin expression.  
TMPRSS6 activity suppresses the expression of hepcidin.  Therefore, TMPRSS6 inhibition 
attenuates negative regulation of hepcidin resulting in increased hepcidin expression. 
β-Thalassemia is a disease characterized by inappropriately low levels of hepcidin.  There is 
strong evidence from in vivo models of β-Thalassemia that TMPRSS6 suppression by raising 
hepcidin expression may be an effective therapeutic strategy to counter the hypo-hepcidinemic 
state of β-Thalassemia. 
This approach is supported by data generated using a mouse-specific Tmprss6 ASO in a mouse 
model of β-thalassemia intermedia where reduction of Tmprss6 with Tmprss6 ASO resulted in 
upregulation of hepcidin associated with reduced intestinal iron mobilization, and amelioration 
of IE, anemia, and iron overload (see the Investigator’s Brochure). 
Thus, the mode of action of Tmprss6-ASO therapy is to suppress TMPRSS6, a negative 
regulator of hepcidin expression, resulting in substantial hepcidin induction.  This results in a 
unique dual action, first impairing intestinal iron uptake resulting in reduced total body iron, and 
secondly, a substantial improvement in hematological parameters due to less erythroid toxicity 
manifesting as improved anemia, IE, and hemolytic parameters. 

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Furthermore, ISIS 702843 has been evaluated in healthy volunteers in a Phase 1 study where 
dose-dependent increases in serum hepcidin levels and decreases in serum TSAT and serum iron 
levels were observed following administration of ISIS 702843 (see the Investigator’s Brochure), 
providing initial human pharmacological evidence that TMPRSS6 suppression with ISIS 702843 
can effectively induce hepcidin associated with its expected downstream impact on iron 
metabolism. 
2.3. 
ISIS 702843 

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2.3.3. 
Preclinical Experience 
Detailed information concerning the preclinical studies conducted with ISIS 702843 can be 
found in the Investigator’s Brochure. 
2.3.4. 
Clinical Experience 
Detailed information concerning the clinical studies conducted with ISIS 702843 can be found in 
the Investigator’s Brochure.  A summary is included below. 
The safety and tolerability of ISIS 702843 was evaluated in a total of 36 healthy volunteer 
subjects aged 18-64 in a blinded, placebo-controlled, Phase 1 study ISIS 702843-CS1.  Of these 
36 subjects, 27 received ISIS 702843 and 9 received placebo.  ISIS 702843 was well-tolerated at 
all dose levels evaluated, i.e., up to 60 mg per dose and up to 240 mg total dose (60 mg 
administered as 4 doses over 8 weeks).  ISIS 702843 treatment resulted in decreases in serum 
iron, TSAT, and reticulocyte Hb, and a dose-dependent increase in hepcidin.  There were no 
dose-dependent, clinically meaningful trends in laboratory assessments, and there were no SAEs. 
 
  GalNAc conjugation consistently 
improves the potency of ASOs in humans approximately 20- to 30-fold, and no effects on 
platelet, renal, or hepatic parameters have been identified from assessment of integrated 
laboratory test data across all doses tested in Ionis Phase 1 studies of GalNAc-conjugated ASOs 
in this chemical class (Crooke et al. 2018).  Longer-term, Phase 2 data with APO(a)-LRx
 
 have been published, and no significant 
changes in platelet count, renal function, or liver function were observed, and neither was a 
between-group difference in the risk of influenza-like symptoms; the most common adverse 
events among patients who received APO(a)-LRx were injection site reactions, which were 
generally mild (Tsimikas et al. 2020). 

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2.5. 
Benefit-Risk Assessment 
Detailed information concerning the benefit-risk assessment of ISIS 702843 can be found in the 
Investigator’s Brochure. 
2.5.1. 
Benefit Assessment 
While ISIS 702843 has been administered to healthy volunteers, it has not been administered to 
patients with β-thalassemia intermedia.  In such patients, TMPRSS6 is a critical negative 
regulator of hepcidin expression. 
ISIS 702843 inhibits TMPRSS6 protein production which, in turn, upregulates hepcidin.  
Increased production of hepcidin is anticipated to have therapeutic benefit in patients with 
chronic IE, anemia, and iron overload that is driven by inappropriately low levels of hepcidin 
with intestinal iron hyperabsorption. 
2.5.2. 
Risk Assessment 
Known potential risks to patients in the study include both disease-specific risks and those 
known potential risks associated with the usage of ASOs. 
Disease-specific risks include: 
1. Potential exacerbation of anemia due to iron-restricted erythropoiesis with ISIS 702843 
usage  
To mitigate this risk, temporary stopping rules have been established to be implemented 
in the event of a confirmed Hb result < 6.0 g/dL that also represents a decrease from 
Baseline of at least 1.0 g/dL, or if in the judgment of the Investigator the patient is 
clinically symptomatic (Section 8.6.1). 

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2. Excessive Hb elevation 
3. To mitigate this risk, temporary stopping rules have been established to be implemented 
in the event of either (i) a confirmed Hb result ≥ 12.5 g/dL, or (ii) a confirmed Hb 
increase of ≥ 2.0 g/dL within a 4-week period and Hb > 10.5 g/dL (Section 8.6.1). 
4. Disease-related exacerbation of anemia due to intercurrent infection or disease 
progression 
Mitigation strategies include:  Exclusion of advanced severe patients and allowing 
standard-of-care interventions to aggressively treat all disease exacerbations. 
5. Thalassemia intermedia-related safety concerns/morbidities due to increasing severity 
and chronicity of the disease 
These include:  thrombosis, splenic rupture, PHT, leg ulcers, diabetes, abnormal liver 
function, and heart failure.  Mitigation strategies include:  Exclusion or monitoring for 
the above safety concerns and early intervention as per standard of care.  
Potential risks associated with the usage of ASOs include: 
1. AEs at the injection site 
These should be managed by standard treatment of AEs at the injection site. 
2. Thrombocytopenia 
Mitigation strategies include:  Exclusion of patients with history of coagulopathy / 
immune thrombocytopenia, regular platelet monitoring, and implementation of well-
defined platelet stopping rules. 
3. Hepatotoxicity 
Mitigation strategies include:  Regular monitoring of liver function tests (LFTs) and 
implementation of well-defined LFT-related stopping rules. 
4. Nephrotoxicity 
Mitigation strategies include:  Exclusion of patients with impaired renal function, 
i.e., estimated glomerular filtration rate (eGFR) < 45 mL/min/1.73 m2 [using Chronic 
Kidney Disease Epidemiology Collaboration (CKD-EPI) equation] or urine protein-to-
creatinine ratio (UPCR) ≥ 0.50 mg/mg, regular monitoring of renal function, and 
implementation of well-defined renal function test-related stopping rules. 
2.5.3. 
Overall Assessment of Benefit:Risk 
Taking into account the measures taken to minimize risk to patients participating in this study, 
the potential risks identified in association with ISIS 702843 are justified by the anticipated 
benefits that may be afforded to patients with non-transfusion dependent -thalassemia 
intermedia for which there are currently no known effective disease-modifying therapies. 
2.5.4. 
Additional Risks During the COVID-19 Pandemic 
During the Coronavirus Disease 2019 (COVID-19) pandemic, patients with β-thalassemia 
intermedia face additional risks based on underlying comorbidities stemming from IE, chronic 

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hemolytic anemia, and iron overload; thus, β-thalassemia intermedia patients may be more 
severely affected by COVID-19 relative to the general population (Taher et al. 2020). 
At the present time, preliminary reports are available regarding the COVID-19 mortality risk for 
non-transfusion dependent β-thalassemia patients versus for the general population.  (Karimi et 
al. 2020) reported that in Iran the COVID-19 mortality rate is 26.1% (6/23) for β-thalassemia 
patients, compared to 6.34% for the general population.  However, (Motta et al. 2020) reported 
that there were no deaths among 11 Italian β-thalassemia patients (one of which had 
β-thalassemia intermedia) known to have been infected with the novel severe acute respiratory 
syndrome coronavirus 2 (SARS-CoV-2) that causes COVID-19, suggesting no risk of increased 
severity of COVID-19 in these patients.  A larger number of cases needs to be evaluated before a 
clear conclusion can be drawn with respect to COVID-19 mortality rate in non-transfusion 
dependent β-thalassemia patients. 
To maintain the favorable benefit:risk ratio of ISIS 702843 for non-transfusion dependent 
β-thalassemia intermedia patients (Section 2.5.3), additional measures will be taken during a 
coronavirus disease pandemic to reduce the likelihood that patients participating in this study 
will become infected with the coronavirus that causes the disease.  The mitigation strategies are 
provided in Section 3.8 – Allowances in the Circumstance of a Public Health Emergency.  These 
measures (e.g., replacing scheduled clinic visits with remote assessments or at-home visits or a 
combination) are to be implemented at the discretion of the PI. 
3. 
EXPERIMENTAL PLAN 
3.1. 
Study Design 
ISIS 702843-CS2 is a multi-center, randomized, open-label study of SC administered 
ISIS 702843 in patients with non-transfusion dependent β-Thalassemia Intermedia. 
The study will comprise 3 cohorts – Cohorts A, B, and C.  However, upon Amendment 2 
approval, (i) the dose level for Cohorts A and B will become the same at 120 mg ISIS 702843, 
and (ii) no new patients will be randomized to Cohort A.  There will be approximately 
12 eligible patients in Cohorts A and B combined, and approximately 12 eligible patients in 
Cohort C, for a total of approximately 24 eligible patients overall.  These patients will be 
stratified based on Screening Mean Hb for Eligibility (defined in Section 6.1.1), low (≤ 8.0 g/dL) 
and high (> 8.0 g/dL).  Then patients will be randomized in parallel to Cohort B (120 mg 
ISIS 702843 per dose) or Cohort C (120 mg ISIS 702843 per dose for three consecutive doses, 
followed by 160 mg ISIS 702843 per dose, if dose escalation is allowed based on a 
demonstration of adequate safety). 
Dose escalation to 160 mg ISIS 702843 in Cohort C will be done on an individual patient basis, 
and only after clinical and laboratory safety evaluations related to the prior dose (scheduled to be 
28 days prior) have been completed, and there is an acceptable safety profile as determined by 
the Investigator and the Sponsor Medical Monitor.  Safety data to be reviewed include AEs and 
concomitant medications.  For dose escalation to be considered, a patient must not have met a 
temporary or permanent stopping rule (Section 8.6) at any time since their prior 3 consecutive 
doses (scheduled to be 28, 56, and 84 days prior). 

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In addition, ISIS 702843 dose adjustments (decreases and increases to the proposed maximum 
clinical dose of 160 mg per 28-day interval) are permitted in all three cohorts, as described in 
Section 8.7. 
Each patient will be treated for up to 2 years, receiving up to 27 doses of ISIS 702843, with a 
planned 28-day interval between each dose. 
This is an open-label study.  Nevertheless, to facilitate obtaining objective feedback from the 
patients on their quality of life measures, it is preferable that patients not be informed of how 
their dose compares to the dosing levels of other cohorts and individual patients. 
3.2. 
Number of Study Centers 
This study will be conducted at multiple centers worldwide, including locations planned in 
Southeast Asia, Australia, and Mediterranean countries. 
3.3. 
Number of Patients 
The study will enroll approximately 24 evaluable patients overall, with approximately 
12 evaluable patients in Cohorts A and B combined, and approximately 12 evaluable patients in 
Cohort C.  Patients who terminate early from the study may be replaced, with a maximum of 
3 replacements for Cohorts A and B combined, and with a maximum of 3 replacements for 
Cohort C.  Patients who discontinue after Day 365 (Week 53) will not be replaced.  Each 
additional patient will be assigned to the same cohort and stratum (i.e., Hb ≤ 8.0 g/dL, or Hb 
> 8.0 g/dL) as the patient they are replacing.  Before a fit is identified, patients who do not 
qualify for that stratum will still be enrolled in the study, including into that cohort.  
The maximum enrollment for the study will be limited to 30 patients or until enrollment is closed 
by the Sponsor.  The Sponsor may close enrollment to one cohort before another; for example, it 
is likely that enrollment to Cohort B will be closed before enrollment to Cohort C because the 
intent is to have approximately 12 evaluable patients in Cohorts A and B combined, and 
approximately 12 evaluable patients in Cohort C. 
3.4. 
Overall Study Duration and Follow-up 
The study will consist of Screening, Treatment, and Post-Treatment periods.  Please refer to the 
Schedule of Procedures in Appendix A.  
The length of each patient’s participation in the study is approximately 29 months that includes 
an approximately 2-month Screening Period, a 24-month Treatment Period, and a 3-month Post-
Treatment Period (PTP). 
Patients who discontinue from ISIS 702843 treatment and agree to remain in the study will 
attend the following clinic visits:  Early Termination from Treatment (ETFT), PTP Visit 1, PTP 
Visit 2, and PTP Last Visit.  If the patient is unable or unwilling to participate in all of these 
visits, the PI should determine the follow-up procedures the patient would agree to complete.  
Every effort should be made to complete the ETFT procedures and observations at the time of 
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Patients may be required to attend additional visits for monitoring of AEs or abnormal 
investigation results.  The frequency of additional monitoring will be determined by the 
Investigator in consultation with the Medical Monitor. 
3.4.1. 
Screening 
Patient eligibility for the study will be determined within 8 weeks prior to study entry.  Four 
Screening Visits (SVs) are planned – SV1, SV2, SV3, and SV4: 
• SV1 supports all initial Screening evaluations 
• SV2 supports additional Hematology testing related to the evaluation of Inclusion 
Criterion 5, and the collection of additional information related to the following 
measures of disease severity, quality of life, and functional status of the patient:  
NTDT-PRO©, SF-36, PGIC, ISGA, FACIT-Fatigue, and 6MWT with pulse oximetry 
• SV3 supports additional Hematology testing related to the evaluation of Inclusion 
Criterion 5, and analysis of Chemistry Panel, Urinalysis, and Coagulation Panel 
samples to provide results for these parameters closer to Day 1 than is SV1.  No 
Clinic Visit is scheduled for SV3; blood and urine samples may be collected at Study 
Clinic, at a local phlebotomy clinic, or by a home healthcare provider, at PI 
discretion.  The testing should be done at the central laboratory except when 
Section 3.8 applies, in which case a local laboratory is acceptable provided that the 
local laboratory results are recorded by the site into the electronic database. 
• SV4 supports additional Hematology testing related to the evaluation of Inclusion 
Criterion 5.  No Clinic Visit is scheduled for SV4; blood and urine samples may be 
collected at Study Clinic, at a local phlebotomy clinic, or by a home healthcare 
provider, at PI discretion.  The testing should be done at the central laboratory except 
when Section 3.8 applies, in which case a local laboratory is acceptable provided that 
the local laboratory results are recorded by the site into the electronic database. 
Magnetic resonance imaging (MRI; needed to evaluate Inclusion Criterion 6) and Ultrasound 
may be performed anytime within the Screening Period; however, it is preferred for these tests to 
be performed once the patient has met all other Inclusion/Exclusion criteria, with the exception 
of Inclusion Criterion 5 because this criterion is evaluated based on all Hb measurements taken 
in the Screening Period.  MRI and Ultrasound should be conducted within 1 week of one another 
– ideally on the same day. 
3.4.2. 
Treatment 
Eligible patients will be stratified based on Screening Mean Hb for Eligibility (defined in 
Section 6.1.1), low (≤ 8.0 g/dL) and high (> 8.0 g/dL).  Then patients will be randomized in 
parallel to Cohort B (120 mg ISIS 702843 per dose) or Cohort C (120 mg ISIS 702843 per dose 
for three consecutive doses, followed by 160 mg ISIS 702843 per dose, if dose escalation is 
allowed based on a demonstration of adequate safety [Section 3.1]).  No patients will be 
randomized to Cohort A after Amendment 2 approval. 
Unless the allowances in the circumstance of a public health emergency apply (Section 3.8), 
through Day 365 (Week 53) these patients will report to the Study Center for each ISIS 702843 

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administration, with all doses being administered by delegated staff or by trained 
patient/caregiver under the observation of Study Center staff, and with a planned 28-day interval 
between each dose.  After Day 365 (Week 53) – earlier if Section 3.8 applies – self-
administration at home is allowed after appropriate training of patient/caregiver, with training 
related to the injection step itself encouraged to start as early as Day 1 (e.g., patient or caregiver 
observes the injection on Day 1 and performs the injection(s) under the observation of Study 
Center staff at subsequent visits).  Thus, planned clinic visits are less frequent after Day 365 
(Week 53), despite the planned interval between each dose remaining 28 days throughout the 
Treatment Period.  In the absence of self-administration training, ISIS 702843 will continue to be 
administered, with the planned interval between each dose remaining 28 days, either at the Study 
Center by delegated staff or via home visits by Study Center staff or home healthcare providers. 
3.4.3. 
Post-Treatment 
Patients are to return to the Study Center for follow-up visits on the following study days from 
Day 1:  757, 785, and 820.  Note that these values for study day from Day 1 are only accurate for 
those patients who do not discontinue from ISIS 702843 treatment.  For this reason, these study 
days from Day 1 are also referred to as PTP Visit 1, PTP Visit 2, and PTP Last Visit.  The final 
study visit will be PTP Last Visit. 
3.5. 
End-of-Study 
The End-of-Study is defined as the date of the last visit of the last patient. 
3.6. 
Internal Safety Committee 
An external Data and Safety Monitoring Board will not be utilized for this study. 
Data will be reviewed by an internal safety committee.  This committee will be comprised of at 
least 2 physicians who are experienced in the conduct of clinical trials, and are independent of 
any other elements of the conduct of the study.  This committee will be assembled to 
independently review safety, tolerability, and, as needed, efficacy data collected during this 
study.  
Based on its ongoing assessment of safety, tolerability, and efficacy of ISIS 702843, this 
committee will provide recommendations to the study team for modifying, stopping, or 
continuing the study as planned.  These decisions will be recorded in the minutes of the 
meetings. Details on the safety assessments, frequency of review, meeting schedules, and access 
to data will be outlined in the internal safety committee Charter and Statistical Analysis Plan 
(SAP). 
Safety will be monitored in an ongoing fashion throughout the study by the Medical Monitor and 
the Drug Safety Physician. 
3.7. 
Dose Adjustments 
Patients will be randomized in parallel to 1 of the planned cohorts, with randomization to 
Cohort A stopping upon Amendment 2 approval (Section 4.2). 

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ISIS 702843 dose adjustments (increases and decreases) in addition to the dose escalation to 
160 mg planned in Cohort C (Section 3.1) will be permitted (Section 8.7).  These adjustments 
may be applicable to one or both of the following:  (i) an entire cohort, but only after the first 
interim analysis; (ii) an individual patient, but only after that individual has completed PK and 
PD evaluations associated with Day 281 (Week 41). 
3.8. 
Allowances in the Circumstance of a Public Health Emergency 
If an investigative site or the clinical trial patients associated with that site experience a public 
health emergency, such as a pandemic, then throughout that time the following changes to what 
is written elsewhere in this protocol are permissible, at the discretion of the PI, provided that all 
ICH, GCP, and regulatory requirements associated with the study are still upheld.  These 
allowances may be implemented at any stage of the study: Screening Period, Treatment Period, 
and Post-Treatment Period. What is considered a public health emergency is based on 
circumstances and procedures at the site, and the judgment of the PI.  The time at which a public 
health emergency has resolved to sufficient extent such that these allowances are no longer 
applicable is based on the judgment of the PI in consultation with the Medical Monitor. 
• Remote assessments and at-home visits: Even when an investigative site remains 
open to clinical trial patients coming on site, social distancing strategies may result in 
some patients being unwilling or unable to attend protocol-specific clinic visits.  For 
such reasons, scheduled clinic visits may be replaced by remote assessments (via 
videoconference or telephone call) or at-home visits or a combination, provided that 
these are properly documented.  This may be accomplished by at-home visits by 
Study Center staff or home healthcare providers, with incorporation of 
videoconference or telephone assessments by Study Center staff or designee. 
• Randomization: When a patient is found to be eligible for the study, the decision 
regarding if and when the patient will be randomized is based on the judgment of the 
PI in consultation with the Medical Monitor.  Randomization may be delayed by up 
to 1 month without rescreening. 
• Safety assessments: Every effort should be made to continue performing safety 
assessments on schedule.  This may require remote assessments (e.g., for adverse 
events and concomitant medications) by Study Center staff, and it may require at-
home visits (e.g., for blood draws, urine samples, physical examination, vital signs) 
by Study Center staff or home healthcare providers.  Which safety assessments are 
considered critical, for example to support a decision on whether to administer the 
next scheduled dose of ISIS 702843 to a patient, is to be determined on a case-by-
case basis by the PI in consultation with the Medical Monitor.  Critical and 
noncritical safety assessments that are delayed beyond the protocol-specific visit 
windows will be considered major and minor, respectively, protocol deviations. 
• Reporting of protocol deviations: All protocol deviations that are caused by a public 
health emergency should be documented as such; for example, include in the 
description of the protocol deviation that it is related to COVID-19.  The impact such 
protocol deviations had on the study is to be summarized in the clinical study report.  

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This summary is considered sufficient notification of the EC / IRB for minor protocol 
deviations that were caused by a public health emergency. 
• Laboratory and imaging assessments associated with primary or secondary endpoints: 
Every effort should be made to perform on schedule Hematology throughout the 
Screening Period, on Day 1, and at Weeks 27 and 53; and LIC at Screening and at 
Week 53.  For Hematology, this may require at-home visits by Study Center staff or 
home healthcare providers.  Delays to these assessments beyond the protocol-specific 
visit windows will be considered major protocol deviations.  For a given patient, the 
imaging center and machine used for MRI should not be changed from that used to 
determine Baseline, and such a change at Week 53 will be considered a major 
protocol deviation. 
• All other laboratory and imaging assessments: Other than critical safety assessments 
and those assessments that are associated with primary or secondary endpoints 
(above), laboratory and imaging assessments that are delayed beyond the protocol-
specific visit windows will be considered minor protocol deviations.  All assessments 
that are missed will be considered major protocol deviations.  For a given patient, it is 
preferable not to change the imaging center and machine used for DEXA, 
Echocardiography, and Ultrasound from that used to determine Baseline, and such a 
change will be considered a minor protocol deviation. 
• Evaluations of disease severity and quality of life: PGIC, FACIT-Fatigue, NTDT-
PRO©, and SF-36 surveys may be completed during remote assessments 
(videoconference or telephone) or at-home visits; this may include the patient 
providing verbal answers that another study-related individual documents.  The ISGA 
survey may be completed at the discretion of the PI.  Surveys that are delayed beyond 
the protocol-specific visit windows will be considered minor protocol deviations.  
Surveys that are missed will be considered major protocol deviations. 
• Evaluations of functional status of the patient: Planned occurrences of the 6MWT 
with pulse oximetry that are delayed beyond the protocol-specific visit windows will 
be considered minor protocol deviations.  Planned occurrences of the 6MWT with 
pulse oximetry that are missed will be considered major protocol deviations. 
• ISIS 702843 administration: Self-administration is permissible at and before Day 365 
(Week 53) after appropriate training of patient/caregiver.  To support this eventuality, 
note that training of patient/caregiver may begin as early as Day 1 (Section 3.4.2 ).  
Also permissible is ISIS 702843 administration during an at-home visit by a Study 
Center staff member or a home healthcare provider, within the scope of their training 
and qualifications, as appropriate. 
− To support ISIS 702843 administration at home, delivery of study drug to the 
patient may be undertaken at the discretion of the PI, based on local and regional 
regulations for transporting investigational product. 
• Visit windows: All visit windows will remain as given in Appendix A .  Each 
assessment or event (e.g., ISIS 702843 administration) that occurs outside its 
corresponding visit window will be considered a protocol deviation.  For assessments, 

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whether such a protocol deviation is to be considered major or minor is discussed 
earlier in this section.  ISIS 702843 administration that occurs outside the visit 
window will be considered a major protocol deviation. 
• Testing at local laboratories: If it is not practical to conduct testing at the central 
laboratory, then it is permissible to use a local laboratory instead.  In these instances, 
the local laboratory results should be recorded by the site into the electronic database. 
4. 
PATIENT ENROLLMENT 
4.1. 
Screening 
Before patients may be enrolled into the study, the Sponsor requires a copy of the written 
approval of the protocol, informed consent form, and all other patient information and/or 
recruitment materials from the Study Center Ethics Committee (EC) / Institutional Review Board 
(IRB). 
Patients or their legally acceptable representatives must sign the consent form before any 
screening tests or assessments, including fasting prior to screening blood draws, are performed.  
At the time of consent, the patient will be considered enrolled into the study and will be assigned 
a unique screening number before any study procedures, including Screening procedures, are 
performed.  At the time of randomization, patients will be assigned a unique patient 
identification number.  This number will be used to identify the patient throughout the trial, and 
must be used on all study documentation related to that patient.  The screening number and 
patient identification number will remain constant throughout the entire trial.  Screening numbers 
and patient identification numbers, once assigned, will not be re-used. 
4.2. 
Randomization 
Patients will be randomized on Day 1, after all Screening assessments have been completed and 
after the Investigator has verified that they are eligible per criteria in Section 5.1 and 5.2.  No 
patient may begin treatment prior to randomization and assignment of a unique patient 
identification number. 
Eligible patients will be randomized using an automated system, such as Interactive Response 
Technology (IRT).  Patients will be stratified based on Screening Mean Hb for Eligibility 
(defined in Section 6.1.1), low (≤ 8.0 g/dL) and high (> 8.0 g/dL), and then patients will be 
randomized in parallel to Cohort B (120 mg ISIS 702843 per dose) or Cohort C (120 mg 
ISIS 702843 per dose for 3 consecutive doses, followed by 160 mg ISIS 702843 per dose, if dose 
escalation is allowed based on a demonstration of adequate safety [Section 3.1]), following a 
prespecified randomization schema.  No patients will be randomized to Cohort A after 
Amendment 2 approval.  The Sponsor’s designee will prepare the randomization list. 
4.3. 
Replacement of Patients 
Patients who terminate early from the study may be replaced, with a maximum of 3 replacements 
for Cohorts A and B combined, and with a maximum of 3 replacements for Cohort C.  Patients 
who discontinue after Day 365 (Week 53) will not be replaced.  Each additional patient will be 

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assigned to the same cohort and stratum (i.e., Hb ≤ 8.0 g/dL, or Hb > 8.0 g/dL) as the patient 
they are replacing.  Before a fit is identified, patients who do not qualify for that stratum will still 
be enrolled in the study, including into that cohort. 
The maximum enrollment for the study will be limited to 30 patients or until enrollment is closed 
by the Sponsor.  The Sponsor may close enrollment to one cohort before another; for example, it 
is likely that enrollment to Cohort B will be closed before enrollment to Cohort C because the 
intent is to have approximately 12 evaluable patients in Cohorts A and B combined, and 
approximately 12 evaluable patients in Cohort C. 
4.4. 
Treatment Assignment 
This is an open-label study.  Nevertheless, to facilitate obtaining objective feedback from the 
patients on their quality of life measures, it is preferable that patients not be informed of how 
their dose compares to the dosing levels of other cohorts and individual patients. 
5. 
PATIENT ELIGIBILITY 
To be eligible to participate in this study, candidates must meet the following eligibility criteria 
within 8 weeks of Study Day 1.  The Medical Monitor may be consulted if any questions arise 
regarding Inclusion or Exclusion Criteria listed below.  The mean of all values obtained during 
the Screening Period is generally considered sufficient when making a decision regarding 
eligibility; however, the Medical Monitor will also consider trends in the data and the 
significance of one or more individual values that are outside of acceptable limits when making a 
determination. 
5.1. 
Inclusion Criteria 
1. Patient must have given written informed consent and be able to comply with all study 
requirements 
2. Aged 18-65 years old, inclusive, at the time of informed consent 
3. Clinical diagnosis of -Thalassemia Intermedia with genotypic confirmation of -globin 
gene mutations including but not limited to Hemoglobin E (HbE)/-thalassemia 
4. Patient must be non-transfusion dependent as defined by:  No more than 8 transfusions in 
the past 12-month period, and no transfusions in the 8-week period prior to Day 1 
5. Mean Hb within the range 6.0–10.5 g/dL, inclusive, with this mean based on all Hb 
measurements taken in the Screening Period that are at least 6 weeks after the most recent 
transfusion for that patient.  This mean must be based on at least two Hb measurements. 
6. LIC within the range of 3.0–20.0 mg Fe/g dry weight, inclusive 
7. Chelators will be permitted provided the dose has not been increased for at least 2 months 
prior to Day 1, with LIC > 5.0 mg Fe/g dry weight and serum ferritin > 300 ng/mL 
8. Females must be non-pregnant and non-lactating, one of the following:  (i) surgically 
sterile (e.g., tubal occlusion, hysterectomy, bilateral salpingectomy, bilateral 

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oophorectomy), (ii) postmenopausal (defined as 12 months of spontaneous amenorrhea 
without an alternative medical cause and follicle stimulating hormone [FSH] levels in the 
postmenopausal range for the laboratory involved), (iii) abstinent*, or (iv) if engaged in 
sexual relations and of child-bearing potential, the patient must be using a highly 
effective (Section 6.3.1) contraceptive method from the time of signing the informed 
consent until at least 13 weeks after the last dose of ISIS 702843. 
Males must be one of the following:  (i) surgically sterile, (ii) abstinent*, or (iii) if 
engaged in sexual relations with a female of child-bearing potential, the patient must be 
using a highly effective (Section 6.3.1) contraceptive method from the time of signing the 
informed consent until at least 13 weeks after the last dose of ISIS 702843. 
* Abstinence is only acceptable as true abstinence, i.e., when this is in line with the 
preferred and usual lifestyle of the patient.  Periodic abstinence (e.g., calendar, 
ovulation, symptothermal, post-ovulation methods), declaration of abstinence for the 
duration of a trial, and withdrawal are not acceptable methods of contraception. 
5.2. 
Exclusion Criteria 
1. Genotypic confirmation of either α-globin gene triplication or sickle hemoglobin 
(HbS)/-thalassemia, as determined by genetic assessment of a panel of blood-related 
disorders 
2. Clinically significant abnormalities in medical history or physical examination, which at 
the discretion of the PI will pose significant additional risk to the patient in participating 
in the study 
3. Clinically significant abnormalities in Screening laboratory values that would render a 
patient unsuitable for inclusion, at the discretion of the PI 
4. Current use of iron-chelation therapy if LIC is 3.0–5.0 mg Fe/g dry weight, inclusive, or 
if serum ferritin ≤ 300 ng/mL 
5. Symptomatic splenomegaly, including abdominal pain or organ obstruction, or evidence 
of hypersplenism, such as low white blood cell (WBC) count and/or low platelets 
6. Platelet count Screening laboratory results < 120,000/mm3 or > 1,000,000/mm3, or any 
other clinically significant abnormalities in platelet count Screening laboratory values 
that would render a patient unsuitable for inclusion 
7. Significant concurrent/recent coagulopathy; history of non-traumatic significant bleeding; 
history of immune thrombocytopenic purpura (ITP); current use of SC anti-coagulants; 
history of thrombotic events, including stroke or DVT 
8. Clinically significant renal dysfunction which at the discretion of the PI will pose 
significant additional risk to the patient in participating in the study 
9. Either of the following confirmed manifestations of renal dysfunction:  
9a.  eGFR < 45 mL/min/1.73 m2, using CKD-EPI equation 
9b.  Proteinuria manifesting as UPCR ≥ 0.50 mg/mg 

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10. Clinically significant liver function test (LFT) abnormalities at the discretion of the PI 
11. Alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) > 3.0 × ULN 
12. Historical diagnosis of cirrhosis, or current signs and symptoms of cirrhosis 
13. Fasting blood glucose > 2.0 × ULN 
14. Significant PHT defined as tricuspid regurgitation > 3.0 meters per second (m/s) on 
echocardiography and/or requiring treatment 
15. Uncontrolled hypertension (which for this protocol is considered > 140 mm Hg systolic 
or > 90 mm Hg diastolic) 
16. Heart failure class 3 or higher (New York Heart Association, NYHA) 
17. Ejection fraction < 50% by echocardiogram, multigated acquisition (MUGA), or cardiac 
magnetic resonance imaging (MRI) 
18. Patients unable to have MRI performed, for example, because of a pacemaker or 
implantable cardioverter-defibrillator. (MRI is being used to measure LIC.) 
19. Active infection requiring systemic antiviral or antimicrobial therapy that will not be 
completed prior to Day 1 
20. Active infection with human immunodeficiency virus (HIV), hepatitis C, or hepatitis B 
diagnosed by initial serological testing and confirmed with RNA testing, or prior 
treatment for hepatitis C.  Patients at Screening who test positive by serology, but 
negative by RNA may be allowed in consultation with the Sponsor Medical Monitor 
21. Unwillingness to comply with study procedures, including follow-up, as specified by this 
protocol, or unwillingness to cooperate fully with the Investigator 
22. Recent introduction of hydroxyurea (6 months prior to Day 1) 
23. Treatment with or exposure to another investigational drug, biological agent, ASO, 
small interfering ribonucleic acid (siRNA), or device within 1 month of Screening, or 
5 half-lives of investigational agent, whichever is longer; or: 
• Treatment with or exposure to sotatercept (ACE-011), luspatercept-aamt (Reblozyl®), 
or ruxolitinib (Jakafi®) within 4 months of Screening 
• Treatment with or exposure to hematopoietic stimulating agents (e.g., EPOs) or any 
hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) (e.g., roxadustat, 
vadadustat, daprodustat, molidustat, desidustat) within 8 weeks of Day 1 
• Prior bone marrow transplant, stem cell transplant, or gene therapy 
24. Regular use of alcohol within 6 months prior to Screening [> 7 drinks/wk for females, 
> 14 drinks/wk for males (1 drink = 5 ounces [150 mL] of wine or 12 ounces [360 mL] of 
beer or 1.5 ounces [45 mL] of hard liquor)] 
25. Surgery associated with significant blood loss within 4 months of Screening, splenectomy 
within 12 months of Screening, or splenectomy scheduled during the Treatment Period 

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26. Use of iron supplements, including iron-containing vitamins, within 4 months of 
Screening 
27. Pregnant or lactating 
28. Have any other conditions which, in the opinion of the PI, would make the patient 
unsuitable for inclusion, or could interfere with the patient participating in or completing 
the study 
29. Active infection with the novel severe acute respiratory syndrome coronavirus 2 (SARS-
CoV-2) that causes COVID-19.  (Note:  It is acceptable to receive COVID-19 
vaccinations while in this study, including in the Screening Period, but it is preferred that 
there is an interval of at least 7-10 days between each vaccination and ISIS 702843 dose.) 
6. 
STUDY PROCEDURES 
6.1. 
Study Schedule 
All required study procedures are outlined in Appendices A–C.  The safety of ISIS 702843 will 
be monitored in an ongoing fashion throughout the study by the Investigators, the Medical 
Monitor, the Drug Safety Physician, and an internal safety committee (Section 3.6). 
6.1.1. 
Screening and Baseline 
Written informed consent for the study will be obtained prior to the performance of any study-
related procedures, including screening procedures and fasting prior to screening blood draws.  
An 8-week period, during which 4 screening visits are planned (Section 3.4.1), is provided for 
completing screening assessments and determining patient eligibility for the study.  Safety labs 
may be retested for determination of patient eligibility after consultation with the Medical 
Monitor. 
During the Screening Period: 
• Patients will undergo a medical history and physical examination including vital 
signs, 12-lead ECG, and have blood and urine samples taken for clinical laboratory 
testing, including chemistry panel, iron metabolism panel, hematology, coagulation, 
FSH, thyroid panel, and urinalysis 
• A blood sample will be taken for genotyping of -globin variants (related to Inclusion 
Criterion 3) and a genetic assessment of a panel of blood-related disorders that will 
include determination of α-globin copy number and whether the patient has 
exclusionary sickle hemoglobin (HbS)/-thalassemia (related to Exclusion Criterion 
1) 
• The patient’s transfusion history will be documented, taking into account, at a 
minimum, all blood transfusions performed in the past 12-month period; a longer 
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• The patient’s history regarding use of chelation will be documented, taking into 
account, at a minimum, all chelator usage in the past 12-month period; a longer 
history over the previous 3 years or more is preferred 
• MRI will be performed to assess LIC, spleen iron concentration, and, if feasible, bone 
marrow iron concentration, as well as liver and spleen volume.  Ultrasound will be 
performed to assess liver and spleen size.  MRI and Ultrasound may be carried out 
anytime within the Screening Period; however, it is preferred for these evaluations to 
be performed once the patient has met all other Inclusion/Exclusion criteria, with the 
exception of Inclusion Criterion 5 because this criterion is evaluated based on all Hb 
measurements taken in the Screening Period, as described below (Screening Mean Hb 
for Eligibility).  In the Screening Period and at all applicable time points in the 
Treatment Period, MRI and Ultrasound should be conducted within 1 week of one 
another – ideally on the same day. 
• Additional information will be collected related to the following measures of disease 
severity, quality of life, and functional status of the patient:  NTDT-PRO©, SF-36, 
PGIC, ISGA, FACIT-Fatigue, and 6MWT with pulse oximetry.  This information 
will be collected twice during the Screening Period:  at SV1 and SV2. 
Screening Mean Hb for Eligibility 
Screening Mean Hb for Eligibility is determined for the purposes of eligibility, and is based on 
all Hb measurements that were taken in the Screening Period, and this mean is used to evaluate 
Inclusion Criterion 5.  Each Hb measurement used for the calculation of this mean must be taken 
at least 6 weeks after the most recent transfusion for that patient.  This mean must be based on at 
least 2 Hb measurements. 
Baseline Hb for Analysis 
Baseline Hb for Analysis is defined as the mean of all Hb measurements that were taken in the 
Screening Period and Day 1, pre-dose.  Each Hb measurement used for the calculation of this 
mean must be taken at least 6 weeks after the most recent transfusion for that patient.  This mean 
must be based on at least 2 Hb measurements (See Section 10.4). 
Baseline for all Other Attributes 
Baseline for all other attributes is defined in Section 10.4. 
6.1.2. 
Treatment Period 
During the 2-year Treatment Period, each patient will receive up to 27 SC doses of ISIS 702843, 
with a planned 28-day interval between each dose (i.e., Day 1 [Week 1], Day 29 [Week 5], 
Day 57 [Week 9], …, Day 729 [Week 105]).  Unless the allowances in the circumstance of a 
public health emergency apply (Section 3.8), through Day 365 (Week 53) these patients will 
report to the Study Center for each ISIS 702843 administration, with all doses being 
administered by delegated staff or by trained patient/caregiver under the observation of Study 
Center staff.  After Day 365 (Week 53) – earlier if Section 3.8 applies – self-administration at 
home is allowed after appropriate training of patient/caregiver. 

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Safety and clinical laboratory evaluations, as well as blood sampling for PK analysis, will be 
performed periodically throughout the Treatment Period (Appendices A–C).  Any AEs and 
concomitant medications will be recorded.  All safety data, including AEs and concomitant 
medications, will be reviewed by the Medical Monitor and the Drug Safety Physician on an 
ongoing basis throughout the study. 
Patients who discontinue from ISIS 702843 treatment and agree to remain in the study will 
attend the following clinic visits:  ETFT, PTP Visit 1, PTP Visit 2, and PTP Last Visit.  If the 
patient is unable or unwilling to participate in all of these visits, the PI should determine the 
follow-up procedures the patient would agree to complete.  Every effort should be made to 
complete the ETFT procedures and observations at the time of withdrawal. 
6.1.3. 
Post-Treatment Period 
After the last dose, scheduled for Day 729 (Week 105) – but will occur earlier for early 
termination patients – patients will return to the clinic for safety assessments at 4- to 5-week 
intervals, for a total of 3 PTP visits spanning 13 weeks. 
Safety and clinical laboratory evaluations, as well as blood sampling for PK analysis, will be 
performed periodically throughout the PTP (Appendix A–Appendix C).  Any AEs and 
concomitant medications will be recorded.  All safety data, including AEs and concomitant 
medications, will be reviewed by the Medical Monitor and the Drug Safety Physician on an 
ongoing basis throughout the study. 
6.2. 
Study Assessments 
6.2.1. 
Physical Exams and Vital Signs 
Physical exams and vital signs will be performed as indicated in the Schedule of Procedures 
(Appendix A).  Vital signs include weight (at specific visits), blood pressure (BP), heart rate, 
respiratory rate, and body temperature.  Blood pressure and heart rate will be recorded after the 
patient has been in a sitting (semi-supine) position for at least 5 minutes, using the same arm 
(preferentially the left arm).  Height will be measured at Screening. 
6.2.1.1. 
Leg Ulcers 
An evaluation for the presence of leg ulcers will be part of each physical examination - not only 
the full physical examination to be performed at Screening but also the abbreviated physical 
examination to be conducted at the times indicated in Appendix A, to assess changes from 
Screening.  Leg ulcers will be measured (shortest and longest axes) and documented via 
photographs taken from a consistent distance and with a ruler next to the ulcer for reference of 
length. 
6.2.2. 
Laboratory and Imaging Assessments 
Laboratory analyte samples will be collected throughout the study as indicated in Appendix A.  
A list of these analytes is contained in Appendix B.  Blood chemistry should be taken after 
fasting for approximately 8-10 hours.  During this time, the patient can drink water and they 
should ensure that they consume sufficient water in order to not become dehydrated.  Due to the 

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length of time between visits, a reminder should be communicated to the patient prior to each 
visit where a fasting blood sample is collected. 
Investigators may, at their discretion, test specific laboratory parameters at their local laboratory 
for safety assessments prior to dosing. In these instances, the local laboratory results should be 
recorded by the site into the electronic database. 
Sampling time for hepcidin testing is preferably at the same time of day from one occurrence to 
the next for a given patient; ideally, this consistent sampling time will be in the morning. 
PK blood sampling will occur prior to dosing at several time-points throughout the Treatment 
Period as well as post-dose on Day 1 and Day 197 (Week 29).  This will require patients to 
remain at the clinic for approximately 6 hours (Day 1) and 3 hours (Day 197 [Week 29]) after 
ISIS 702843 dosing – see Appendix C. 
If the platelet value, serum creatinine, or liver enzyme tests are uninterpretable (e.g., due to 
clumping, hemolysis, or quantity not sufficient) or missing, then a repeat blood specimen should 
be re-drawn as soon as possible – ideally within 7 days, should be within 2 weeks – which may 
require an unscheduled visit or blood draw. 
Investigators may, at their discretion, test specific laboratory parameters that may be prone to 
clotting, clumping, or hemolysis (e.g., hematology samples) at their local laboratory, in addition 
to the required central laboratory samples.  In these instances, the local laboratory results should 
be recorded by the site into the electronic database. 
Platelet count will be monitored as described in Section 8.5.2.  The Investigator should review all 
platelet count results within 48 hours of receipt.  In the event of any platelet count 
< 100,000/mm3, monitoring frequency and dosing should be adjusted as recommended in 
Section 8.6.6.  In the event of an unreportable platelet count result (e.g., due to a hemolyzed or 
clumped blood sample), patient dosing cannot continue until another sample is tested (at a 
central or local laboratory) and determined not to have met a stopping rule. 
Any case of a platelet count < 50,000/mm3 should be reported to the Sponsor in an expedited 
fashion (see Section 8.6.6). The Medical Monitor will discuss the assessment and treatment of 
such patients with the PI, considering whether any additional tests should be conducted besides 
the Platelet Count Safety Panel (Appendix B), for example, if they know or suspect that the 
patient has a morbidity related to thrombocytopenia. 
6.2.2.1. 
ECG 
ECGs will be recorded after the patient has been resting in a supine position for at least 
5 minutes.  ECGs will be performed in triplicate at the times indicated in Appendix A. 
6.2.2.2. 
DEXA Scans 
Dual energy X-ray absorptiometry (DEXA) scans will be conducted at the times indicated in 
Appendix A, using standardized procedures and settings.  For a given patient, it is preferable not 
to change the imaging center and machine used from that used to determine Baseline, and such a 
change will be considered a minor protocol deviation. 

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6.2.2.3. 
Echocardiography 
Echocardiography for assessment of cardiac function will be conducted at the times indicated in 
Appendix A.  For a given patient, it is preferable not to change the imaging center and machine 
used from that used to determine Baseline, and such a change will be considered a minor 
protocol deviation. 
6.2.2.4. 
MRI 
MRI of the liver, spleen, and bone marrow will be conducted at the times indicated in 
Appendix A using standardized procedures and settings.  MRIs will be evaluated by independent 
central readers, to assess LIC, spleen iron concentration, and, if feasible, bone marrow iron 
concentration, as well as liver and spleen volume.  For a given patient, the imaging center and 
machine used should not be changed from that used to determine Baseline, and such a change at 
Week 53 will be considered a major protocol deviation. 
6.2.2.5. 
Ultrasound 
Ultrasound of the liver and spleen will be conducted at the times indicated in Appendix A, using 
standardized procedures and settings, to assess liver and spleen size.  For a given patient, it is 
preferable not to change the imaging center and machine used from that used to determine 
Baseline, and such a change will be considered a minor protocol deviation. 
6.2.3. 
Disease Severity and Quality of Life Measures 
6.2.3.1. 
Use of Chelation 
Standard of care interventions, including (i) introduction of chelation – although preferably this 
will not occur before Day 169 (Week 25), (ii) adjustment of chelator dose or formulation – 
although preferably dose increases or formulation changes will not occur before Day 169 (Week 
25), and (iii) temporary suspension of chelation therapy, are permitted, at the discretion of the PI.  
The date of each introduction of chelation or adjustment of chelator dose or formulation while a 
patient is on study will be documented, along with relevant details related to the chelator, 
including product name and dosing regimen. 
6.2.3.2. 
Number of Transfusions 
Standard of care interventions, including transfusion, are permitted, at the discretion of the 
Investigator.  The date of each transfusion performed while a patient is on study will be 
documented. 
6.2.3.3. 
NTDT-PRO©, SF-36, PGIC, ISGA, and FACIT-Fatigue 
Standard application of these surveys (see Appendix E) at the times indicated in Appendix A.  
Preferably, these surveys should be completed before ISIS 702843 administration.  If surveys are 
completed after the ISIS 702843 administration at that clinic visit, this will not be considered a 
protocol deviation that will impact efficacy. 

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6.2.4. 
Functional Status of the Patient Measure 
6.2.4.1. 
6MWT with Pulse Oximetry 
Standard application of the 6MWT (see Appendix E) at the times indicated in Appendix A.  
Throughout the 6MWT, the patient will be wearing a pulse oximeter to collect oxygen saturation 
and heart rate data continuously throughout the test.  Preferably, the 6MWT with pulse oximetry 
should be completed before ISIS 702843 administration.  If the 6MWT with pulse oximetry is 
completed after the ISIS 702843 administration at that clinic visit, this will not be considered a 
protocol deviation that will impact efficacy. 
6.3. 
Restriction on the Lifestyle of Patients 
6.3.1. 
Contraception Requirements 
Male patients must refrain from sperm donation and either be abstinent† or, if engaged in sexual 
relations with a woman of child-bearing potential (WOCBP), the patient must use a highly 
effective contraception method from the time of signing the informed consent form until at least 
13 weeks after their last dose of ISIS 702843.  Highly effective contraception for male patients 
comprises a vasectomy with negative semen analysis at follow-up, or the female partner is using 
a highly effective contraception method.  Highly-effective contraception for WOCBP partners of 
male patients is described in the next paragraph.  Male patients with partners who are pregnant 
must use condoms to ensure that the fetus is not exposed to ISIS 702843. 
WOCBP patients must refrain from egg donation and either be abstinent† or use a highly 
effective contraception method from the time of signing the informed consent form until at least 
13 weeks after their last dose of ISIS 702843.  Highly effective contraception for WOCBP 
patients – and WOCBP partners of male patients – comprises surgical sterilization (e.g., bilateral 
tubal occlusion), hormonal contraception associated with inhibition of ovulation (combined 
estrogen and progestogen containing, or progestogen-only contraceptives), intrauterine 
contraception device, or intrauterine hormone-releasing system (IUS). 
†Note:  Abstinence (i.e., refraining from heterosexual intercourse throughout the duration of 
study participation) is only acceptable as true abstinence, i.e., when this is in line 
with the preferred and usual lifestyle of the patient.  Periodic abstinence (e.g., 
calendar, ovulation, symptothermal, post-ovulation methods), declaration of 
abstinence for the duration of a trial, and withdrawal are not acceptable methods of 
contraception. 
For the purposes of this study, WOCBP are defined as any female who has experienced 
menarche, and who does not meet one of the following conditions: 
• Postmenopausal: 12 months of spontaneous amenorrhea in females > 55 years of age 
or, in females ≤ 55 years of age, 12 months of spontaneous amenorrhea without an 

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alternative medical cause and FSH levels in the postmenopausal range for the 
laboratory involved 
• 6 weeks after surgical bilateral oophorectomy with or without hysterectomy 
• Post hysterectomy 
6.3.2. 
Other Requirements 
All patients will be required to fast for approximately 8–10 hours before visits requiring fasted 
blood sampling.  Due to the length of time between visits, a reminder should be communicated to 
the patient prior to each visit where a fasting blood sample is collected. 
7. 
STUDY DRUG 
7.2. 
Packaging and Labeling 
The Sponsor will provide the Investigator with packaged ISIS 702843, labeled in accordance 
with specific country regulatory requirements. 
7.3. 
Study Drug Accountability 
The study staff is required to document the receipt, dispensing, and return/destruction of 
ISIS 702843 supplies provided by the Sponsor, according to Sponsor instruction and in 
accordance with institutional policy. 
8. 
TREATMENT OF PATIENTS 
8.1. 
ISIS 702843 Administration 
Unless the allowances in the circumstance of a public health emergency apply (Section 3.8), 
through Day 365 (Week 53) ISIS 702843 will be administered SC at the clinic, either by trained 
Study Center staff or by the trained patient/caregiver under the observation of Study Center staff.  
After that visit – earlier if Section 3.8 applies – SC administration away from the clinic (e.g., at 
the patient’s home) is allowed, and this may be accomplished by any trained individual, 
including a caregiver or the patient themselves (referred to in this protocol as “self-
administration”). 
The planned doses and corresponding volumes to be administered are shown in Table 1.  
However, ISIS 702843 dose may be adjusted as described in Section 8.7.   
Vials are for single use only. 

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8.5. 
Safety Monitoring Rules 
Please refer also to the ‘Guidance for Investigator’ section of the Investigator’s Brochure. 
For the purposes of safety monitoring, Baseline is defined in Section 10.4. 
In addition to the standard monitoring of clinical safety parameters, the following guidelines are 
provided for the monitoring of selected parameters chosen based on preclinical and clinical 
observations. 
Confirmation Guidance:  At any time during the study (Treatment or Post-Treatment), the initial 
clinical laboratory results meeting the safety monitoring criteria presented below must be 
confirmed by performing measurements (ideally in the same laboratory that performed the 
initial measurement) on new specimens.  All new specimen collections should take place as soon 
as possible – ideally within 3 to 7 days of the initial collection – which may require an 
unscheduled visit or blood draw.  For stopping rules, if the initial laboratory result is observed 
during the Treatment Period, the results from the retest must be available prior to administering 
the next dose of ISIS 702843. 
Redosing Guidance:  Patients with initial laboratory test values that reach a pausing or stopping 
rule must not be re-dosed until the retest results are available.  In general, patients who do not 
meet the stopping rules based upon retest may continue dosing.  However, the Investigator and 
the Sponsor Medical Monitor (or appropriately qualified designee) should confer as to whether 
additional close monitoring of the patient is required.  If any of the stopping criteria described 
below (refer to Section 8.6.1 to Section 8.6.6) are met, the patient will be permanently 
discontinued from further treatment with ISIS 702843, evaluated fully as outlined below and in 
consultation with the Medical Monitor or appropriately qualified designee, and will be followed 
up in accordance with Section 8.8 of the protocol. 
8.5.1. 
Safety Monitoring Rules for Liver Chemistry Tests 
The following rules are adapted from the draft guidance for industry, “Drug-Induced Liver 
Injury: Premarketing Clinical Evaluation,” issued by the U.S. Department of Health and Human 
Services, Food and Drug Administration, July 2009. 
In the event of an ALT or AST measurement that is > the greater of (i) 2 × Baseline or (ii) 4 × 
ULN if Baseline is > ULN at any time during the study (Treatment or Post-Treatment), the initial 
measurement(s) should be confirmed as described above.  Additional, confirmatory 
measurements should also be performed if ALT or AST levels increase to > 6 × ULN. 
Frequency of Repeat Measurements:  Patients with confirmed ALT or AST levels > the greater 
of (i) 2 × Baseline or (ii) 4 × ULN if Baseline is > ULN, should have their liver chemistry tests 
(ALT, AST, ALP, INR, and total bilirubin) retested at least once weekly until ALT and AST 
levels become ≤ (i) 1.2 × ULN or (ii) 1.2 × Baseline if Baseline is > ULN, as applicable. 
Further Investigation into Liver Chemistry Elevations:  For patients with confirmed ALT or AST 
levels > the greater of (i) 2 × Baseline or (ii) 4 × ULN if Baseline is > ULN, the following 
evaluations should be performed: 
• Obtain a more detailed history of symptoms and prior and concurrent diseases 

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• Obtain further history for concomitant drug use (including nonprescription 
medications, herbal and dietary supplement preparations), alcohol use, recreational 
drug use, and special diets 
• Obtain a history for exposure to environmental chemical agents and travel 
• Serology for viral hepatitis (hepatitis A virus immunoglobulin M [HAV IgM], 
HBsAg, hepatitis C virus [HCV] antibody, Cytomegalovirus [CMV] IgM, and 
Epstein-Barr virus [EBV] antibody panel) 
• Serology for autoimmune hepatitis (e.g., antinuclear antibody [ANA]) 
Additional liver evaluations, including gastroenterology/hepatology consultations, hepatic 
computed tomography or MRI scans, may be performed at the discretion of the Investigator, in 
consultation with the Medical Monitor.  Repetition of the above evaluations should be 
considered if a patient’s ALT and/or AST levels reach > 6 × ULN. 
Baseline is defined in Section 10.4. 
8.5.2. 
Safety Monitoring Rules for Platelet Count Results 
Platelet count will be monitored at least every 4 weeks through Day 197 (Week 29).  From then 
through the remainder of the Treatment Period, platelets will be monitored every 8 weeks.  
During the PTP, platelets will be monitored as per schedule (see Appendix A Schedule of 
Procedures).  The Investigator should review all platelet count results within 48 hours of receipt.  
If a patient’s platelet count falls between < 100,000/mm3 and 75,000/mm3, then the patient’s 
platelet counts should be monitored at least weekly.  In case of platelet reduction to 
< 75,000/mm3, the platelet monitoring rules defined in Temporary and Permanent Stopping rules 
(Section 8.6.6) should be followed. 
Any unreportable platelet count result (e.g., caused by a hemolyzed, clumped, or clotted sample) 
must be rechecked and determined not to have met a stopping rule before dosing can continue. 
Any case of a platelet count < 50,000/mm3 should be reported to the Sponsor in an expedited 
fashion (see Section 8.6.6). The Medical Monitor will discuss the assessment and treatment of 
such patients with the PI, considering whether any additional tests should be conducted besides 
the Platelet Count Safety Panel (Appendix B), for example, if they know or suspect that the 
patient has a morbidity related to thrombocytopenia. 
8.5.3. 
Safety Monitoring for Minor Bleeding Events 
Minor bleeding events are those that do not fulfill the criteria for major bleeding (MB) or 
clinically relevant non-major bleeding events (which are defined in Section 8.6.6), for example 
excess bruising, petechiae, gingival bleeding on brushing teeth.  If a minor bleeding event 
occurs, additional testing of coagulation parameters (aPTT, PT, INR) and platelet count should 
be performed. 
8.6. 
Temporary and Permanent Stopping Rules 
For the purposes of the stopping rules, Baseline is defined in Section 10.4. 

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If ISIS 702843 dosing is paused (i.e., a temporary stopping rule is implemented) and later 
resumed, the next dose should be given at the next Study Day at which dosing is scheduled.  This 
will cause the total number of doses that this patient will receive in the study to be fewer than the 
maximum number of 27. 
8.6.1. 
Temporary Stopping Rules for Hb Results 
In the event of a confirmed Hb result meeting any of the following criteria, ISIS 702843 
treatment will be suspended, at least temporarily: 
1. Confirmed Hb value < 6.0 g/dL and a decrease from Baseline of at least 1.0 g/dL, or if in 
the judgment of the Investigator the patient is clinically symptomatic, or 
2. Confirmed Hb value ≥ 12.5 g/dL, or 
3. Confirmed Hb increase of ≥ 2.0 g/dL within a 4-week period and Hb > 10.5 g/dL 
Confirmation of a Hb result should occur before the next scheduled visit, ideally within 3 to 7 
days after the initial result, which may require an unscheduled visit or blood draw. 
Following temporary stopping of ISIS 702843 treatment, Hb will continue to be monitored on a 
monthly basis or more frequently based on the discretion of the Investigator.  ISIS 702843 
treatment may be resumed in the following circumstances, at the discretion of the Investigator, in 
consultation with the Medical Monitor: 
• If treatment was suspended based on low Hb (the first criterion, above), then 
treatment may be resumed based on a confirmed Hb value ≥ Baseline, for example 
after a transfusion 
• If treatment was suspended based on Hb ≥ 12.5 g/dL (the second criterion, above), 
then treatment may be resumed based on (i) a confirmed Hb value < 12.5 g/dL and 
(ii) at least 2 scheduled doses have been missed 
• If treatment was suspended based on Hb increase of ≥ 2.0 g/dL within a 4-week 
period (the third criterion, above), then treatment may be resumed based on (i) Hb not 
continuing to increase and (ii) at least 2 scheduled doses have been missed 
In all situations, the timing of reintroduction of treatment will be based on the Investigator’s 
judgment on a case-by-case basis and in consultation with the Medical Monitor, ensuring that the 
patient is not subject to undue risk, such as from relatively rapid Hb elevations. 
8.6.2. 
Temporary Stopping Rules for Thalassemia Intermedia Related Safety 
Concerns/ Morbidities 
Patients will be closely monitored for increasing severity and chronicity of their disease. 
If the patient develops any well recognized morbidities of Thalassemia Intermedia that are 
associated with increasing severity and chronicity of the disease, the Investigator, in consultation 
with the Medical Monitor, should consider suspending ISIS 702843 treatment, at least 
temporarily, for example with the following morbidities: 
• Development of symptomatic PHT (i.e., exertional dyspnea), or PHT on 
pharmacologic treatment, or tricuspid regurgitation ˃ 3 m/s on echocardiography 

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ISIS 702843 treatment may resume at the discretion of the Investigator, in consultation with the 
Medical Monitor. 
8.6.3. 
Permanent Stopping Rules for Thalassemia Intermedia Related Safety Concerns 
/ Morbidities 
If the patient develops any well recognized morbidities of Thalassemia Intermedia that are 
associated with increasing severity and chronicity of the disease, the Investigator, in consultation 
with the Medical Monitor, should consider stopping ISIS 702843 treatment permanently, for 
example with the following morbidities: 
1. Development of a clinically confirmed thrombosis, or 
2. Clinical evidence of splenic rupture, or 
3. Development of clinically significant heart failure (NYHA class 3 or higher), or left 
ventricular ejection fraction that is either ˂ 40% absolute or ≥ 20% reduction from 
Baseline 
8.6.4. 
Temporary and Permanent Stopping Rules for Liver Chemistry Elevations 
In the event of a laboratory result meeting any of the following criteria, and the event is without 
an alternative explanation as discussed with the Medical Monitor, dosing of the patient with 
ISIS 702843 will be paused.  Confirmation of a laboratory result should be completed preferably 
within 3 to 7 days – which may require an unscheduled visit or blood draw.  If the result is 
confirmed by a repeat measurement, then dosing of that patient with ISIS 702843 will be stopped 
permanently: 
1. ALT or AST > 10 x ULN, or 
2. ALT or AST > 6 x ULN, which persists for ≥ 2 weeks, or 
3. ALT or AST > the greater of (i) 2 x Baseline or (ii) 4 × ULN if Baseline is > ULN, and 
total bilirubin > 2 × ULN or INR > 1.5, or 
4. ALT or AST > the greater of (i) 2 × Baseline or (ii) 4 × ULN if Baseline is > ULN, and 
the new appearance (i.e., onset coincides with the changes in hepatic enzymes) of fatigue, 
nausea, vomiting, right upper quadrant pain or tenderness, fever, rash, and/or concomitant 
eosinophilia (> ULN) 
8.6.5. 
Temporary and Permanent Stopping Rules for Renal Function Test Results 
In the event of a laboratory result meeting either of the following criteria, dosing of the patient 
with ISIS 702843 will be paused.  Confirmation of a laboratory result should be completed as 
soon as possible – ideally within 7 days, should be within 2 weeks – which may require an 
unscheduled visit or blood draw.  If the result is confirmed by a repeat measurement, then dosing 
of that patient with ISIS 702843 will be stopped permanently: 
1. Serum creatinine increase that is both ≥ 0.3 mg/dL (26.5 µmol/L) and ≥ 40% above 
Baseline creatinine values (Baseline is defined in Section 10.4) 
2. 30% decline in eGFR from Baseline eGFR values 

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In the event of a confirmed UPCR result meeting either of the following criteria, dosing of the 
patient with ISIS 702843 will be paused.  Confirmation of a laboratory result should be 
completed as soon as possible – ideally within 7 days, should be within 2 weeks – which may 
require an unscheduled visit or blood and urine samples: 
1. Proteinuria manifesting as UPCR ≥ 0.50 mg/mg that also represents an increase from 
Baseline of at least 2 ×, or 
2. Proteinuria manifesting as UPCR ≥ 0.70 mg/mg 
Following temporary stopping of ISIS 702843 treatment because of proteinuria, UPCR will 
continue to be monitored on a monthly basis or more frequently based on the discretion of the PI.  
ISIS 702843 treatment may be resumed at the discretion of the PI, in consultation with the 
Medical Monitor, and will be based on factors such as the patient’s historical UPCR results in 
conjunction with other renal parameters. 
The follow-up schedule for any events meeting any of these stopping criteria will be determined 
by the Investigator, in consultation with the Medical Monitor.  At the discretion of the 
Investigator, in consultation with the Medical Monitor, a decision to hold or permanently stop 
ISIS 702843 treatment may be made based on lesser changes in these parameters observed in 
isolation or in association with other renal-related abnormalities. 
8.6.6. 
Temporary and Permanent Stopping Rules for Platelet Count Results 
In the event of any platelet count < 100,000/mm3, monitoring frequency and dosing should be 
adjusted as recommended in the table below. 
 

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Table 2: 
Actions in Patients with Platelet Count ≤ Lower Limit of Normal (LLN) 
Platelet Count 
Dosing Action 
Monitoring  
≤ LLN to 100,000/mm3 
Continue 
Monitor as per protocol 
< 100,000/mm3 to 
75,000/mm3 
Continue 
Monitor at least weekly 
< 75,000/mm3 to 
50,000/mm3, in the 
absence of major bleeding 
or clinically relevant non-
major bleeding (defined 
below) 
Pause 
Monitor at least twice per week until 3 successive values above 
100,000/mm3.  Then monitor weekly until values normalize. 
The suitability of the patient for continued dosing will be 
determined by the Investigator in consultation with the Medical 
Monitor and will be based on factors such as the original rate of 
decline in the patient’s platelet count, whether any bleeding 
events were experienced, and the speed of recovery of platelet 
count after the dose pause.  The patient must have 3 successive 
values above 100,000/mm3 before continued dosing is 
considered. 
< 50,000/mm3 to 
25,000/mm3 
Pause 
Report to the Sponsor in an expedited fashion 
Monitor at least twice per week until 3 successive values above 
75,000/mm3.  Then monitor weekly until values normalize. 
A hematologist consultation may be considered at the discretion 
of the Investigator and Medical Monitor 
Administration of corticosteroids* and a hematologist 
consultation is recommended 
< 25,000/mm3 to 
10,000/mm3 
Permanently 
Discontinue 
Report to the Sponsor in an expedited fashion 
Monitor daily until 2 successive values above 25,000/mm3.  
Then monitor twice per week until 3 successive values above 
75,000/mm3.  Then monitor weekly until values normalize.   
Administration of corticosteroids* and a hematologist 
consultation is recommended 
< 10,000/mm3 
Permanently 
Discontinue 
Report to the Sponsor within 24 hours 
Monitor daily until 2 successive values above 25,000/mm3.  
Then monitor twice per week until 3 successive values above 
75,000/mm3.  Then monitor weekly until values normalize.   
Hospitalize patient and expedite a hematologist consultation 
Administer platelet transfusions and corticosteroids*, if deemed 
necessary 
* Treatment guidelines for immune thrombocytopenia (Provan et al. 2010) recommend dexamethasone 40 mg daily 
for 4 days every 2-4 weeks for 1-4 cycles; prednis(ol)one 0.5-2 mg/kg/d for 2-4 weeks then taper; or parenteral 
methylprednisolone 30 mg/kg/day for 7 days.  (Note:  Patient may require continuation with oral corticosteroids 
after methylprednisolone) 
 
In the event of any platelet count > 1,000,000/mm3, the utility of adjustments to concomitant 
medications (e.g., anti-coagulants) will be determined by the Investigator in consultation with the 
Medical Monitor. 
Definition of Major Bleeding Events (Schulman and Kearon 2005): 
1. Fatal bleeding, and/or 
2. Symptomatic bleeding in a critical area or organ, such as intracranial, intraspinal, 
intraocular, retroperitoneal, intraarterial or pericardial, or intramuscular with 
compartment syndrome 

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3. Clinically overt bleeding leading to transfusion of ≥ 2 units of packed RBC or whole 
blood or a fall in Hb of 2.0 mg/dL (1.24 mmol/L) or more within 24 hours 
Definition of Clinically Relevant Non-Major Bleeding Events 
Clinically relevant non-major bleeding (CRNMB) is defined as overt bleeding not meeting the 
criteria for MB but that resulted, for example, in medical examination, intervention, or had 
clinical consequences for a patient. 
Definition of Minor Bleeding Events 
Minor bleeding events are those that do not fulfill the criteria for MB or CRNMB events (defined 
above), for example excess bruising, petechiae, gingival bleeding on brushing teeth. 
8.7. 
Adjustment of ISIS 702843 Dose and/or Treatment Schedule 
Dose pauses are permitted, as described in Section 8.6. 
Two (2) interim analyses are planned.  The first interim analysis is planned to occur when at least 
20 patients have completed evaluations associated with Day 183 (Week 27).  The second interim 
analysis is planned to occur when at least 16 patients have completed evaluations associated with 
Day 365 (Week 53).  Based on these and/or other analysis(es), ISIS 702843 dose adjustments in 
addition to the dose escalation to 160 mg planned in Cohort C (Section 3.1) will be permitted 
using the criteria numbered 1–4 below as a guide if the data support such a change providing 
additional therapeutic benefit or safety to the patient(s) in the judgment of the Investigator, in 
consultation with the Medical Monitor.  These adjustments may be applicable to: 
• An entire cohort, but only after the first interim analysis 
• An individual patient, but only after that individual has completed PK and PD 
evaluations associated with Day 281 (Week 41) 
Earlier adjustment(s) for an individual patient may occur if it is deemed necessary, and the 
Investigator should discuss these proposed adjustment(s) with the Medical Monitor prior to 
implementation. 
Standard of care interventions, including transfusion, introduction of iron chelation therapy, and 
adjustment of chelator dose or formulation, will be permitted, at the discretion of the 
Investigator.  For example, if serum ferritin decreases to the extent that over-chelation is a 
concern, then it is expected that the Investigator will consider reducing the chelator dose, as 
appropriate, before consideration is given to adjusting the ISIS 702843 dose. 
ISIS 702843 dose adjustments should be considered by the Investigator, in consultation with the 
Medical Monitor, using the following criteria numbered 1-4 below as a guide.  Allowable dose 
levels for all cohorts are 30, 50, and 80 mg (i.e., the initial dose levels for Cohorts A, B, and C, 
respectively, before Amendment 2), and 120 mg (i.e., the initial dose level planned for 
Cohorts A, B, and C after Amendment 2 approval), and 160 mg [i.e., the dose level planned for 
Cohort C after dose escalation, if allowed based on a demonstration of adequate safety 
(Section 3.1), after Amendment 2 approval].  Multiple adjustments (increases and decreases) per 
subject are allowed if the data support such changes providing additional therapeutic benefit or 
safety to the patient(s) in the judgment of the PI, in consultation with the Medical Monitor. 

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1. If ISIS 702843 treatment was suspended based on decreased Hb (the first criterion in 
Section 8.6.1), follow standard of care measures including considering transfusing the 
patient; then, if ISIS 702843 treatment resumes and it is after Day 281 (Week 41) for this 
patient, consider other Hematology and Iron Metabolism Panel measures to determine 
whether the ISIS 702843 dose should be adjusted from the prior dose level.  When 
increasing or decreasing the ISIS 702843 dose for an individual patient, the change 
should not exceed one dose level from the previous, i.e., make one of the following 
changes:  from 30 mg to 50 mg, from 50 mg to 80 mg, from 80 mg to 120 mg, from 
120 mg to 160 mg, from 160 mg to 120 mg, from 120 mg to 80 mg, from 80 mg to 
50 mg, or from 50 mg to 30 mg.  (Exceptions to the practice of not exceeding one dose 
level change per dose adjustment are the following, which are based on Amendment 2: 
the Cohort A dose increase from 30 mg to 120 mg, and the Cohort B dose increase from 
50 mg to 120 mg.) 
2. If ISIS 702843 treatment was suspended based on increased Hb (the second or third 
criteria in Section 8.6.1), then, if ISIS 702843 treatment resumes and it is after Day 281 
(Week 41) for an individual patient, consider decreasing the ISIS 702843 dose to the next 
dose level, as applicable, i.e., from 160 mg to 120 mg, from 120 mg to 80 mg, from 
80 mg to 50 mg, or from 50 mg to 30 mg 
3. If a patient is not exhibiting a notable PD effect (e.g., increase in Hb or decrease in LIC) 
through Day 281 (Week 41) or later, then consider increasing the ISIS 702843 dose to the 
next dose level, as applicable, i.e., from 30 mg to 50 mg, from 50 mg to 80 mg, from 
80 mg to 120 mg, or from 120 mg to 160 mg. 
4. If, at Day 281 (Week 41), Day 365 (Week 53), or Day 533 (Week 77), LIC ≤ 3.0 mg Fe/g 
dry weight, and serum ferritin ≤ 300 ng/mL, follow standard of care measures including 
first consider reducing or suspending chelator treatment, at least temporarily, and only 
thereafter consider decreasing the ISIS 702843 dose to the next dose level, as applicable, 
i.e., from 160 mg to 120 mg, from 120 mg to 80 mg, from 80 mg to 50 mg, or from 
50 mg to 30 mg 
Maximum ISIS 702843 dose will not exceed 160 mg per administration, with a planned 28-day 
interval between each dose (Section 2.4). 
8.8. 
Discontinuation of ISIS 702843 Treatment 
A patient must permanently discontinue ISIS 702843 treatment for any of the following: 
• The patient becomes pregnant.  Report the pregnancy according to instructions in 
Section 9.5.4 
• The patient withdraws consent 
• The patient experiences an AE that in the opinion of the Investigator, in consultation 
with the Medical Monitor, necessitates permanent discontinuation of ISIS 702843 
treatment 
• The patient develops laboratory test abnormalities that meet any of the permanent 
stopping rules listed in Section 8.6.1 to Section 8.6.6  

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The reason for discontinuation of ISIS 702843 treatment must be recorded in the electronic Case 
Report Form (eCRF) and source documentation. 
Patients who discontinue from ISIS 702843 treatment and agree to remain in the study will 
attend the following clinic visits:  ETFT, PTP Visit 1, PTP Visit 2, and PTP Last Visit.  If the 
patient is unable or unwilling to participate in all of these visits, the Investigator should 
determine the follow-up procedures the patient would agree to complete.  Every effort should be 
made to complete the ETFT procedures and observations at the time of withdrawal. 
8.9. 
Withdrawal of Patients from the Study Procedures 
Patients must be withdrawn from study procedures for any of the following: 
• Withdrawal of consent 
• The patient is unwilling or unable to comply with the protocol 
Other reasons for withdrawal of patients from study procedures might include: 
• At the discretion of the Investigator for medical reasons 
• At the discretion of the Investigator or Sponsor for noncompliance 
• Significant protocol deviation 
All efforts will be made to complete and report the observations as thoroughly as possible up to 
the date of withdrawal.  All information, including the reason for withdrawal from study, must be 
recorded in the eCRF. 
Any patient who withdraws consent to participate in the study will be removed from further 
treatment and study observation immediately upon the date of request.  These patients should be 
encouraged to complete the early termination study procedures and observations at the time of 
withdrawal (Appendix A). 
For patients withdrawn for reasons other than withdrawal of consent, every effort should be 
made to complete the early termination of study procedures and observations at the time of 
withdrawal (see Appendix A) and ideally within 4 weeks from the last dose of ISIS 702843.  
If the patient declines or is unable to participate in the above, the Investigator should determine 
the follow-up procedures the patient would agree to complete.  Wherever possible, these patients 
should continue to be followed up via the agreed means to collect information on AEs, 
concomitant medications, and survival status.  At the very least, the patient’s status at the end of 
the protocol defined Study Period should be ascertained and documented wherever possible.  The 
agreed means of follow-up will be documented in the patient records and notified to the Sponsor. 
8.10. 
Concomitant Therapy and Procedures 
The use of concomitant therapies or procedures defined below must be recorded on the patient’s 
eCRF.  Adverse events related to administration of these therapies or procedures must also be 
documented on the appropriate eCRF. 

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8.10.1. 
Concomitant Therapy 
A concomitant therapy is any non-protocol specified drug or substance (including over-the-
counter medications, herbal medications, vitamin supplements, and iron supplements) 
administered at any time from Screening through the end of the PTP. 
Allowed Concomitant Therapies 
Standard-of-care interventions are permitted at the discretion of the PI, and these may include: 
• Blood transfusions 
• Introduction of iron chelation therapy – although preferably this will not occur before 
Day 169 (Week 25) 
• Adjustment of chelator dose or formulation – although preferably dose increases or 
formulation changes will not occur before Day 169 (Week 25) 
− For example, if serum ferritin decreases to the extent that over-chelation is a 
concern, then it is expected that the Investigator will consider reducing the 
chelator dose, as appropriate 
Also allowed is treatment with either luspatercept-aamt (Reblozyl®) or EPO, not both, after 
Day 365 (Week 53). 
Disallowed Concomitant Therapy 
Use of iron supplements, including iron-containing vitamins, is not allowed. 
8.10.2. 
Concomitant Procedures 
A concomitant procedure is any therapeutic intervention (e.g., surgery/biopsy, physical therapy) 
or diagnostic assessment (e.g., blood gas measurement, bacterial cultures) performed at any time 
from Screening through the end of the PTP. 
Allowed Concomitant Procedures 
Standard-of-care procedures are permitted at the discretion of the Investigator. 
Disallowed Concomitant Procedure 
There are no disallowed concomitant procedures. 
8.11. 
Treatment Compliance 
Compliance with treatment dosing is to be monitored and recorded in the eCRF by Study Center 
staff. 
Self-administration will be documented by the patients or (applicable if a caregiver administered 
the dose) caregivers in a dosing diary that will be reviewed periodically by Study Center staff 
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9. 
SERIOUS AND NON-SERIOUS ADVERSE EVENT REPORTING  
9.1. 
Sponsor Review of Safety Information 
Safety information will be collected, reviewed, and evaluated by the Sponsor or designee in 
accordance with the applicable Ionis and/or designee SOPs throughout the conduct of the clinical 
trial. 
Listings of serious adverse events (SAEs) will be provided to the internal safety committee; 
potential safety issues will be reviewed based on the internal safety committee Charter. 
9.2. 
Regulatory Requirements 
The Sponsor or designee is responsible for regulatory submissions and reporting to the 
Investigators of SAEs including suspected unexpected serious adverse reactions (SUSARs) per 
the International Conference on Harmonization (ICH) guidelines E2A and ICH GCP.  
Country-specific regulatory requirements will be followed in accordance with local country 
regulations and guidelines. 
Ethics Committees / Institutional Review Boards will be notified of any SAE according to 
applicable regulations. 
In addition to the Investigator’s assessment of relatedness, the Sponsor or designee will evaluate 
the available information and perform an independent assessment of all reported SAEs and 
determine if there is a reasonable possibility that ISIS 702843 is causally related to a reported 
SAE.  While the Sponsor may upgrade an Investigator’s decision, it is not permissible to 
downgrade the Investigator’s opinion for the purposes of determining whether the SAE meets the 
definition of a SUSAR. 
9.3. 
Definitions 
9.3.1. 
Adverse Event 
An adverse event (AE) can be any unfavorable and unintended sign (including an abnormal 
laboratory finding, for example), symptom, or disease temporally associated with the use of 
medicinal (investigational) product, whether or not the AE is considered related to the medicinal 
(investigational) product. 
An AE can therefore be any of the following: 
• Any unfavorable and unintended sign (including an abnormal laboratory finding), 
symptom, or disease temporally associated with the use of a medicinal product, 
whether or not considered related to the medicinal product 
• Any new disease or exacerbation of an existing disease (a worsening in the character, 
frequency, or severity of a known condition) 
• Recurrence of an intermittent medical condition (e.g., headache) not present at 
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• Any deterioration in a laboratory value or other clinical test (e.g., ECG, X-ray) that is 
associated with symptoms or leads to a change in study treatment or concomitant 
treatment or discontinuation from Study Drug 
• Adverse events that are related to a protocol-mandated intervention, including those 
that occur prior to assignment of study treatment (e.g., screening invasive procedures 
such as biopsies) 
9.3.2. 
Adverse Drug Reaction and Suspected Unexpected Adverse Drug Reaction 
Adverse Drug Reaction (ADR) 
In the pre-approval clinical experience with a new medicinal product or its new usages, 
particularly as the therapeutic dose(s) may not have been established, ADR is defined as follows: 
All noxious and unintended responses to a medicinal product related to any dose should 
be considered adverse drug reactions. 
The phrase “responses to a medicinal product” means that a causal relationship between the 
medicinal product and the AE has been determined by the Sponsor as at least a reasonable 
possibility, i.e., the relationship cannot be ruled out. 
Suspected Unexpected Adverse Drug Reaction  
A suspected unexpected ADR is any ADR, the nature or severity of which is not consistent with 
the applicable product information, e.g., Investigator’s Brochure, for an unapproved medicinal 
(investigational) product. 
A suspected adverse reaction implies a lesser degree of certainty about causality than an adverse 
reaction. 
9.3.3. 
Serious Adverse Event (SAE) 
A SAE is any AE that in the view of either the Investigator or Sponsor, meets any of the 
following criteria: 
• Results in death 
• Is life threatening: that is, poses an immediate risk of death at the time of the event 
− An AE or suspected adverse reaction is considered “life-threatening” if, in the 
view of either the Investigator or Sponsor, its occurrence places the patient at 
immediate risk of death.  It does not include an AE or suspected adverse reaction 
that, had it occurred in a more severe form, might have caused death 
• Requires inpatient hospitalization or prolongation of existing hospitalization 
− Hospitalization is defined as an admission of greater than 24 hours to a medical 
facility and does not always qualify as an AE 
• Results in a persistent or significant incapacity or substantial disruption of the ability 
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• Results in a congenital anomaly or birth defect in the offspring of the patient (whether 
the patient is male or female) 
• Important medical events that may not result in death, are not life-threatening, or do 
not require hospitalization may also be considered serious when, based upon 
appropriate medical judgment, they may jeopardize the patient and may require 
medical or surgical intervention to prevent one of the outcomes listed in this 
definition.  Examples of such medical events include allergic bronchospasm requiring 
intensive treatment in an emergency room or at home, blood dyscrasias or 
convulsions that do not result in inpatient hospitalization, or the development of drug 
dependency or drug abuse 
The terms “severe” and “serious” are not synonymous.  Severity refers to the intensity of an AE 
(e.g., rated as mild, moderate, or severe, or according to National Cancer Institute Common 
Terminology Criteria for Adverse Events [NCI CTCAE]), while seriousness refers to the medical 
significance.  For example, a headache without any further findings has relatively minor medical 
significance, but it may be a severe headache. 
Severity and seriousness need to be independently assessed for each AE recorded on the eCRF. 
9.4. 
Monitoring and Recording Adverse Events 
Any pre-existing conditions or signs and/or symptoms present in a patient prior to the start of the 
study (i.e., before informed consent) should be recorded as Medical History and not recorded as 
AEs unless the pre-existing condition worsened.  The Investigator should always group signs and 
symptoms into a single term that constitutes a single unifying diagnosis if possible.  Before a 
diagnosis is confirmed, all symptoms should be reported as separate AEs. 
9.4.1. 
Serious Adverse Events 
In the interest of patient safety, and in order to fulfill regulatory requirements, all SAEs 
(regardless of their relationship to ISIS 702843) should be reported to the Sponsor or designee 
within 24 hours of the Study Center’s first knowledge of the event.  The collection of SAEs will 
begin after the patient signs the informed consent form and stop at the end of the patient’s 
Follow-up Period which is defined as PTP Last Visit.  When the Investigator is reporting by 
telephone, it is important to speak to someone in person versus leaving a message.  Once the 
patient is randomized, SAEs should be reported using an electronic SAE submission form 
whenever possible.  In situations where the electronic SAE submission is unavailable or an SAE 
occurs prior to the patient’s randomization, a paper Initial Serious Adverse Event Form should 
be completed and a copy should be faxed or emailed to the Sponsor or designee.  For SAEs 
reported after randomization, information submitted on the paper form should be entered into 
EDC as soon as the system becomes available.  The SAE reporting instructions, including the fax 
number and email address can be found in the Investigator site file for the study. 
Detailed follow-up information should be actively sought and promptly submitted electronically, 
or on a Serious Adverse Event Form if reporting by paper, before randomization.  All SAEs will 
be followed until resolution.  SAEs that remain ongoing past the patient’s last protocol-specified 
follow-up visit will be evaluated by the Investigator and Sponsor.  If the Investigator and 

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Sponsor agree the patient’s condition is unlikely to resolve, the Investigator and Sponsor will 
determine the follow-up requirement. 
9.4.2. 
Non-Serious Adverse Events 
The recording of non-serious AEs will begin after the patient signs the informed consent form 
and will stop at the end of the patient’s Follow-up Period, which is defined as PTP Last Visit.  
The Investigator will monitor each patient closely and record all observed or volunteered AEs on 
the Adverse Event Case Report Form. 
9.4.3. 
Evaluation of Adverse Events (Serious and Non-Serious) 
The Investigator’s opinion of the following should be documented on the Adverse Event Case 
Report Form: 
9.4.3.1. 
Relationship to ISIS 702843 
The event’s relationship to ISIS 702843 is characterized by one of the following: 
• Related:  There is clear evidence that the event is related to the use of ISIS 702843, 
e.g., confirmation by positive re-challenge test 
• Possible:  The event cannot be explained by the patient’s medical condition, 
concomitant therapy, or other causes, and there is a plausible temporal relationship 
between the event and ISIS 702843 administration 
• Unlikely/Remote:  An event for which an alternative explanation is more likely 
(e.g., concomitant medications or ongoing medical conditions) or the temporal 
relationship to ISIS 702843 administration and/or exposure suggests that a causal 
relationship is unlikely (For reporting purposes, Unlikely/Remote will be grouped 
together with Not Related) 
• Not Related:  The event can be readily explained by the patient’s underlying medical 
condition, concomitant therapy, or other causes, and therefore, the Investigator 
believes no relationship exists between the event and ISIS 702843 
9.4.3.2. 
Severity 
The severity of AEs and SAEs relating to laboratory tests and adverse events at the injection site 
may be graded based on criteria from the Common Terminology Criteria for Adverse Events 
(CTCAE) Version 5.0, November 2017 (refer to Appendix D). 
Alternatively, the Investigator should classify events and laboratory findings as mild, moderate, 
or severe based on the clinical significance of the event and laboratory finding for that patient, 
for example, laboratory findings related to Hb, ALT, and AST. 
Any AE not listed in Appendix D will be graded as follows: 
• Mild:  The event is easily tolerated by the patient and does not affect the patient’s 
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• Moderate:  The event causes the patient more discomfort and interrupts the patient’s 
usual daily activities 
• Severe:  The event is incapacitating and causes considerable interference with the 
patient’s usual daily activities 
If the event is an SAE, then all applicable seriousness criteria must be indicated (criteria listed in 
Section 9.3.3). 
9.4.3.3. 
Action Taken with ISIS 702843 
Action taken with ISIS 702843 due to the event is characterized by one of the following: 
• None:  No changes were made to ISIS 702843 administration and dose 
• Not Applicable:  SAE/AE was reported during Screening Period prior to 
ISIS 702843 administration 
• Permanently Discontinued:  ISIS 702843 was discontinued and not restarted 
• Temporarily Interrupted, Restarted – Same Dose:  Dosing and/or dosing 
frequency was temporarily interrupted/changed or delayed due to the AE and 
restarted at the same dose 
• Reduced Dose:  Dosing was reduced, temporarily interrupted, or delayed due to the 
AE and restarted at the next lower dose or reduced dosing frequency 
9.4.3.4. 
Treatment Given for Adverse Event 
Any treatment (e.g., medications or procedures) given for the AE should be recorded on the 
Adverse Event Case Report Form.  Treatment should also be recorded on the concomitant 
treatment or ancillary procedures eCRF, as appropriate. 
9.4.3.5. 
Outcome of the Adverse Event 
If the event is a non-serious AE, then the event’s outcome is characterized by one of the 
following: 
• AE Persists:  Patient terminates from the trial and the AE continues 
• Recovered:  Patient recovered completely from the AE 
• Became Serious:  The event became serious (the date that the event became serious 
should be recorded as the Resolution Date of that AE and the Onset Date of the 
corresponding SAE) 
• Change in Severity (if applicable):  AE severity changed 
If the event is an SAE, then the event’s outcome is characterized by one of the following: 
• Ongoing:  SAE continuing 
• Persists (as non-serious AE):  Patient has not fully recovered but the event no longer 
meets serious criteria and should be captured as an AE on the non-serious AE eCRF 
(the SAE resolution date should be entered as the date of onset of that AE) 

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• Recovered:  Patient recovered completely from the SAE (the date of recovery should 
be entered as the SAE resolution date) 
• Recovered with Sequelae:  The signs/symptoms of the reported SAE have improved 
but not completely resolved, and a new baseline for the patient is established since 
full recovery is not expected 
• Fatal:  Patient died (the date of death should be entered as the SAE resolution date) 
• Unknown:  The outcome of the reported SAE is not available, e.g., patient is lost to 
follow-up 
9.4.3.6. 
Follow-up of Adverse Event 
Investigator Follow-Up 
During the Study Period, the Investigator should follow each AE until the event has resolved to 
baseline grade or better, the event is assessed as stable, the patient is lost to follow-up, or the 
patient withdraws consent.  Every effort should be made to follow all SAEs considered to be 
related to ISIS 702843 or related to study procedures until a final outcome can be reported. 
Resolution of AE (with dates) should be documented on the Adverse Event eCRF and in the 
patient’s medical record to facilitate source data verification.  
Investigator should follow-up, or support the Sponsor’s effort to follow up with all pregnancies 
reported during the study from either the study patient or the female partner of male study patient 
until pregnancy outcome is available. 
Sponsor Follow-Up 
For SAEs and pregnancy cases in patients who have completed or terminated study, the Sponsor 
or a designee should follow-up by telephone, fax, email, and/or a monitoring visit to obtain 
additional case details and outcome information (e.g., from hospital discharge summaries, 
consultant reports, autopsy reports) in order to perform an independent medical assessment of the 
reported case. 
9.5. 
Procedures for Handling Special Situations 
9.5.1. 
Abnormalities of Laboratory Tests 
Clinically significant abnormal laboratory test results may, in the opinion of the Investigator, 
constitute or be associated with an AE.  Examples of these include abnormal laboratory results 
that are associated with symptoms, or require treatment, e.g., bleeding due to thrombocytopenia, 
tetany due to hypocalcemia, or cardiac arrhythmias due to hyperkalemia.  Whenever possible, the 
underlying diagnosis should be listed in preference to abnormal laboratory values as AEs.  
Clinically significant abnormalities will be monitored by the Investigator until the parameter 
returns to its baseline value or until agreement is reached between the Investigator and Medical 
Monitor.  Laboratory abnormalities deemed not clinically significant (NCS) by the Investigator 
should not be reported as AEs.  Similarly, laboratory abnormalities reported as AEs by the 
Investigator should be deemed CS on the laboratory sheet. 

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The Investigator is responsible for reviewing and signing all laboratory reports.  The signed 
clinical laboratory reports will serve as source documents and should include the Investigator’s 
assessment of clinical significance of out of range/abnormal laboratory values. 
9.5.2. 
Prescheduled or Elective Procedures or Routinely Scheduled Treatments 
A prescheduled or elective procedure or a routinely scheduled treatment will not be considered 
an SAE, even if the patient is hospitalized; the Study Center must document all of the following: 
• The prescheduled or elective procedure or routinely scheduled treatment was 
scheduled (or was on a waiting list to be scheduled) prior to obtaining the patient’s 
consent to participate in the study 
• The condition that required the prescheduled or elective procedure or routinely 
scheduled treatment was present before and did not worsen or progress in the opinion 
of the Investigator between the patient’s consent to participate in the study and the 
timing of the procedure or treatment 
• The prescheduled or elective procedure or routinely scheduled treatment is the sole 
reason for the intervention or hospital admission 
9.5.3. 
Dosing Errors 
ISIS 702843 dosing errors (including overdose, underdose, and administration error) should be 
documented as Protocol Deviations.  A brief description should be provided in the deviation, 
including whether the patient was symptomatic (list symptoms) or asymptomatic, and the event 
accidental or intentional. 
Dosing details should be captured on the Dosing Case Report Form.  If the patient takes a dose 
of ISIS 702843 that exceeds protocol specifications and the patient is symptomatic, then the 
symptom(s) should be documented as an AE and be reported per Section 9.4. 
An overdose is the accidental or intentional use of a drug in an amount higher than the dose 
being studied.  An overdose or incorrect administration of study treatment is not itself an AE, but 
it may result in an AE.  All AEs associated with an overdose or incorrect administration of 
ISIS 702843 should be recorded on the Adverse Event eCRF.  If the associated AE fulfills 
seriousness criteria, the event should be reported to the Sponsor immediately (i.e., no more than 
24 hours after learning of the event). 
Should an overdose occur, the Investigator or designee should refer to the Guidance to 
Investigator’s section of the Investigator’s Brochure and contact the Sponsor or designee within 
24 hours. 
9.5.4. 
Contraception and Pregnancy 
Male patients and female patients of childbearing potential must continue to use highly effective 
contraception with their partners, or refrain from sexual activity, as described in Section 6.3.1. 
If a patient becomes pregnant or a pregnancy is suspected, or if a male patient makes or believes 
that he has made someone pregnant during the study, then the Study Center staff must be 
informed immediately.  An Initial Pregnancy Form should be submitted to the Sponsor or 

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designee within 24 hours of first learning of the occurrence of pregnancy.  Follow-up 
information including delivery or termination is reported by designating as ‘Follow-up’ on the 
Pregnancy Forms and reported within 24 hours. 
Payment for all aspects of obstetrical care, child or related care will be the patient’s 
responsibility.   
Female patients:  If a suspected pregnancy occurs while on the study (including follow-up), a 
pregnancy test will be performed.  The patient with a confirmed pregnancy will be immediately 
withdrawn from treatment with ISIS 702843.  However, the patient will be encouraged to 
complete the post-treatment follow-up portion of the study to the extent that study procedures do 
not interfere with the pregnancy.  Regardless of continued study participation, the progress of the 
pregnancy will be followed until the outcome of the pregnancy is known (i.e., delivery, elective 
termination, or spontaneous abortion).  If the pregnancy results in the birth of a child, the Study 
Center and Sponsor may require access to the mother and infant’s medical records to obtain 
additional information relevant to the pregnancy progress and outcome.  A longer follow-up may 
be required if a newborn child experiences a medical condition.  Follow-up will be performed to 
the extent permitted by the applicable regulations and privacy considerations; e.g., pregnancy 
informed consent form may be required. 
Male patients:  The progress of the pregnancy of a male patient’s partner should be followed 
until the outcome of the pregnancy is known (i.e., delivery, elective termination, or spontaneous 
abortion).  If the pregnancy results in the birth of a child, the Study Center and Sponsor may 
follow-up with the mother and may request access to the mother and infant’s medical 
records to obtain additional information relevant to the pregnancy progress and outcome.  A 
longer follow-up may be required if a newborn child experiences a medical condition.  
Follow-up will be performed to the extent permitted by the applicable regulations and privacy 
considerations; e.g., partner pregnancy informed consent form may be required. 
10. 
STATISTICAL CONSIDERATIONS 
10.1. 
Stratification 
Eligible patients will be stratified based on Screening Mean Hb for Eligibility (defined in 
Section 6.1.1), low (≤ 8.0 g/dL) and high (> 8.0 g/dL). 
10.2. 
Sample Size Considerations 
There is no statistical rationale for the selected sample size of the study dose treatment cohorts. 
The sample size was based on prior experience to ensure that the safety, tolerability, PK, and PD 
of ISIS 702843 will be adequately assessed while minimizing unnecessary patient exposure.  The 
study will enroll approximately 24 evaluable patients overall, with approximately 12 evaluable 
patients in Cohorts A and B combined, and approximately 12 evaluable patients in Cohort C, 
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10.3. 
Populations 
Safety Set:  All randomized patients who received at least 1 dose of ISIS 702843. 
PK Set:  All randomized patients who received at least 1 dose of ISIS 702843 and have at least 
1 evaluable PK sample. 
Full Analysis Set (FAS):  All randomized patients who received at least 1 dose of ISIS 702843 
and who have at least 1 Hb assessment collected after Day 1. 
Other populations will be defined in the SAP. 
10.4. 
Definitions of Baseline 
For all attributes other than Hematology parameters, Baseline is defined as the last measurement 
prior to first dose of ISIS 702843. 
For hematology parameters, Baseline is defined as the mean of all measurements taken in the 
Screening Period and Day 1, pre-dose.  Each measurement used for the calculation of Baseline 
must be taken at least 6 weeks after the most recent transfusion for that patient.  Baseline must be 
based on at least 2 measurements. 
10.5. 
Interim Analyses 
Two (2) interim analyses are planned: 
• The first interim analysis is planned to occur when at least 20 patients have completed 
evaluations associated with Day 183 (Week 27).  The main purpose of this analysis is 
to assess Hb, other Hematology measures, and Iron Metabolism Panel measures, with 
this information being used to support decisions related to the potential for dose 
adjustments applicable to an entire cohort (see Section 8.7). 
• The second interim analysis is planned to occur when at least 16 patients have 
completed evaluations associated with Day 365 (Week 53).  The main purposes of 
this analysis are to assess LIC, and to further assess the measures associated with the 
first interim analysis. 
An internal safety committee (Section 3.6) will independently review safety, tolerability, and, as 
needed, efficacy data collected during this study.  Based on its ongoing assessment of safety, 
tolerability, and efficacy of ISIS 702843, this committee will provide recommendations to the 
study team for modifying, stopping, or continuing the study as planned. 
10.6. 
Planned Methods of Analysis 
All eCRF data, laboratory data transfers, and any outcomes derived from the data will be 
provided in the patient data listings.  Patient data listings will be presented for all patients 
randomized into the study.  
Descriptive summary statistics including n, mean, median, standard deviation, interquartile range 
(25th percentile, 75th percentile), and range (minimum, maximum) for continuous variables, and 
counts and percentages for categorical variables will be used to summarize most data by cohort 
and total.  

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10.6.1. 
Demographic and Baseline Characteristics 
Demographic and Baseline characteristics will be summarized using descriptive statistics by 
cohort and total.  Patient randomization and disposition will be summarized by cohort and total.  
All patients randomized will be included in a summary of patient disposition. 
10.6.2. 
Safety Analysis 
Treatment duration and amount of ISIS 702843 received will be summarized by cohort and total, 
as well as reasons for withdrawal from ISIS 702843 treatment. 
Patient incidence rates of all treatment-emergent adverse events (AEs with onset after the first 
dose of ISIS 702843) and SAEs will be tabulated by cohort and total using Medical Dictionary 
for Regulatory Activities (MedDRATM) coding system by system organ class, preferred term, 
relationship to ISIS 702843, and severity.  Narratives of deaths, serious and significant TEAEs, 
including early study withdrawals due to AEs, will also be provided. 
Laboratory tests to ensure patient safety, including chemistry panel, complete blood count (CBC) 
with differential, and coagulation panel, will be summarized by study visits for each cohort.  
These safety variables will also be presented as change and percent change from Baseline over 
time after ISIS 702843 administration, as appropriate.  In addition, the number of patients who 
experience abnormalities in clinical laboratory evaluations will be summarized. 
Vital sign and ECG measures will be tabulated by cohort and total. 
10.6.3. 
Efficacy Analyses 
The primary efficacy analysis for proportion of patients achieving ≥ 1.0 g/dL increase from 
Baseline in Hb at Week 27 will be summarized descriptively by cohort.  Additional summary by 
the stratification factor will also be provided. 
Secondary efficacy analyses will be performed in a similar way to primary efficacy analysis, and 
will include: 
• Proportion of patients achieving ≥ 1.5 g/dL increase from Baseline in Hb at Week 53 
• Proportion of patients achieving ≥ 1.0 mg Fe/g dry weight decrease from Baseline in 
LIC at Week 53 
Exploratory efficacy analyses will be performed in a similar way to primary efficacy analysis, 
and will include: 
• Mean change (absolute and percentage) from Baseline with respect to each scheduled 
visit after Day 1, for the parameters in each of the following categories (see 
Section 1.2.3): 
− IE 
− Measures of iron overload 
− Hepcidin 
− Measures of anemia 

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Details will be presented in the SAP. 
10.6.4. 
Pharmacokinetic Analysis 
The plasma PK of ISIS 702843 (as total full-length ASO, including fully conjugated, partially 
conjugated, and unconjugated ISIS 702843) will be assessed following SC administration.  
Non-compartmental PK analysis of ISIS 702843 (as total full-length ASO) will be carried out on 
each individual patient data set. 
Other plasma PK parameters, as appropriate, may be determined or calculated at the discretion of 
the PK scientist. 
Metabolite identification and profiling may be conducted on select plasma samples. 
Plasma PK parameters will be summarized using descriptive statistics.  Additional details 
regarding the PK analysis will be described in the SAP. 
Analysis of potential exposure-response relationship between ISIS 702843 and relevant 
biomarkers may be explored, as deemed appropriate. 
10.6.5. 
Additional Exploratory Analyses 
Analysis of the parameters in the categories (see Section 1.2.3) listed below will be conducted in 
a similar manner as described in Section 10.6.3 for mean change (absolute and percentage) from 
Baseline with respect to each scheduled visit after Day 1.  Details will be presented in the SAP. 
• Hemolysis 
• Coagulation profile changes 
• Disease severity and quality of life measures 
• Functional status of the patient 
11. 
INVESTIGATOR’S REGULATORY OBLIGATIONS 
11.1. 
Informed Consent 
The written informed consent document should be prepared in the language(s) of the potential 
patient population, based on an English version provided by the Sponsor or designee. 
Before a patient’s participation in the trial, the Investigator is responsible for obtaining written 
informed consent from the patient after adequate explanation of the aims, methods, anticipated 
benefits, and potential hazards of the study, and before any protocol-specific screening 
procedures or any ISIS 702843 is administered.  The patient must be given sufficient time to 
consider whether to participate in the study. 
The acquisition of informed consent and the patient’s agreement or refusal to notify his/her 
primary care physician should be documented in the patient’s medical records, and the informed 
consent form should be signed and personally dated by the patient and by the person who 
conducted the informed consent discussion (not necessarily an Investigator).  The original signed 
informed consent form should be retained in the Study Master File and in any other locations 

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required by institutional policy, and a copy of the signed consent form should be provided to the 
patient. 
11.2. 
Ethical Conduct of the Study 
All applicable regulations and guidelines of current Good Clinical Practice (GCP) as well as the 
demands of national drug and data protection laws and other applicable regulatory requirements 
must be followed.  
11.3. 
Independent Ethics Committee / Institutional Review Board 
A copy of the protocol, proposed informed consent form, other written patient information, and 
any proposed advertising material must be submitted to the EC / Institutional Review Board 
(IRB) for written approval.  A copy of the written approval of the protocol and informed consent 
form must be received by the Sponsor before recruitment of patients into the study and shipment 
of ISIS 702843.  A copy of the written approval of any other items/materials that must be 
approved by the Study Center or EC / IRB must also be received by the Sponsor before 
recruitment of patients into the study and shipment of ISIS 702843.  The Investigator’s Brochure 
must be submitted to the EC / IRB for acknowledgement. 
The Investigator must submit to and, where necessary, obtain approval from the EC / IRB for all 
subsequent protocol amendments and changes to the informed consent document.  The 
Investigator should notify the EC / IRB of deviations from the protocol in accordance with 
ICH GCP.  The Investigator should also notify the EC / IRB of SAEs occurring at the Study 
Center and other AE reports received from the Sponsor, in accordance with local procedures. 
The Investigator will be responsible for obtaining annual EC / IRB approval/renewal throughout 
the duration of the study.  Copies of the Investigator’s reports, all EC / IRB submissions and the 
EC / IRB continuance of approval must be sent to the Sponsor. 
11.4. 
Patient Confidentiality 
The Investigator must ensure that the patient’s confidentiality is maintained.  On the CRFs or 
other documents submitted to the Sponsor or designee, patients should be identified by initials 
(if permitted by local law) and a patient identification number only.  Documents that are not for 
submission to the Sponsor or designee (e.g., signed informed consent forms) should be kept in 
strict confidence by the Investigator. 
The Investigator must comply with all applicable National and local regulations / ICH GCP 
Guidelines, including US Food & Drug regulations and, where applicable, the European Union’s 
General Data Protection Regulation.  In compliance with such regulations, it is required that the 
Investigator and institution permit authorized representatives of the company, of the regulatory 
agency(s), and the EC / IRB direct access to review the patient’s original medical records for 
verification of study-related procedures and data.  Direct access includes examining, analyzing, 
verifying, and reproducing any records and reports that are important to the evaluation of the 
study.  The Investigator is obligated to inform and obtain the consent of the patient to permit 
named representatives to have access to his/her study-related records without violating the 
confidentiality of the patient. 

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12. 
ADMINISTRATIVE AND LEGAL OBLIGATIONS 
12.1. 
Protocol Amendments 
Protocol amendments must be made only with the prior approval of the Sponsor.  Agreement 
from the Investigator must be obtained for all protocol amendments and amendments to the 
informed consent document.  The regulatory authority and EC / IRB must be informed of all 
amendments and give approval for any amendments likely to affect the safety of the patients or 
the conduct of the trial.  The Investigator must send a copy of the approval letter from the EC / 
IRB to the Sponsor. 
12.2. 
Study Termination 
The Sponsor reserves the right to terminate the study.  The Investigator reserves the right to 
terminate their participation in the study, according to the terms of the site contract.  The 
Investigator / Sponsor should notify the EC / IRB in writing of the trial’s completion or early 
termination, and send a copy of the notification to the Sponsor. 
12.3. 
Study Documentation and Storage 
An eCRF utilizing an Electronic Data Capture (EDC) application will be used for this study. 
The Investigator should ensure that all appropriately qualified persons to whom he/she has 
delegated trial duties are recorded on a Sponsor-approved Delegation of Site Responsibilities 
Form. 
Source documents are original documents, data, and records from which the patient’s CRF data 
are obtained.  These include but are not limited to hospital records, clinical and office charts, 
laboratory and pharmacy records, imaging, and correspondence.  In this study, eCRFs may not 
be used as source documents. 
The Investigator and Study Center staff are responsible for maintaining a comprehensive and 
centralized filing system of all study-related (essential) documentation in accordance with ICH 
GCP, suitable for inspection at any time by representatives from the Sponsor or designee and/or 
applicable regulatory authorities.  Elements should include: 
• Patient files containing informed consents and original source documents supporting 
entries in the eCRFs 
• Study files containing the protocol with all amendments, Investigator’s Brochure, 
copies of pre-study documentation and all correspondence to and from the EC / IRB 
and the Sponsor or designee 
• If drug supplies are maintained at the Study Center, proof of receipt, Study Drug 
Product Accountability Record, Return of Study Drug Product for Destruction or 
confirmation of on-site destruction, final Study Drug product reconciliation, and all 
drug-related correspondence 
All original source documents supporting entries in the eCRFs must be maintained and be readily 
available. 

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No study document should be destroyed without prior written agreement between the Sponsor 
and the Investigator.  Should the Investigator wish to assign the study records to another party or 
move them to another location, he/she must notify the Sponsor. 
12.4. 
Study Monitoring 
The Sponsor representative and regulatory authority inspectors are responsible for contacting and 
visiting the Investigator for the purpose of inspecting the facilities and, upon request, inspecting 
the various records of the trial (e.g., CRFs and other pertinent data) provided that patient 
confidentiality is respected. 
The Sponsor monitor or designee is responsible for inspecting the CRFs at regular intervals 
throughout the study to verify adherence to the protocol; completeness, accuracy, and 
consistency of the data; and adherence to local regulations on the conduct of clinical research.  
The monitor should have access to patient medical records and other study-related records 
needed to verify the entries on the CRFs. 
The Investigator agrees to cooperate with the monitor to ensure that any problems detected in the 
course of these monitoring visits, including delays in completing CRFs, are resolved. 
In accordance with ICH GCP and the Sponsor’s audit plans, this study may be selected for audit 
by representatives from the Sponsor’s Clinical Quality Assurance Department (or designees).  
Inspection of Study Center facilities (e.g., pharmacy, drug storage areas, laboratories) and review 
of study-related records will occur to evaluate the trial conduct and compliance with the 
protocol, ICH GCP, and applicable regulatory requirements. 
To ensure the quality of clinical data, a clinical data management review will be performed on 
patient data received by the Sponsor or designee.  During this review, patient data will be 
checked for consistency, omissions, and any apparent discrepancies.  In addition, the data will be 
reviewed for adherence to the protocol and GCP.  To resolve any questions arising from the 
clinical data management review process, data queries and/or Study Center notifications will be 
sent to the Study Center for completion and return to Sponsor or designee.  All data transfers 
must comply with applicable law, including US Food & Drug regulations and, where applicable, 
the European Union’s General Data Protection Regulation. 
The Investigator will sign and date the indicated places on the CRF.  These signatures will 
indicate that the Investigator inspected or reviewed the data on the CRF, the data queries, and the 
Study Center notifications, and agrees with the content. 
12.5. 
Language 
Case report forms must be completed in English.  Generic names and trade names are acceptable 
for concomitant medications.  Combination medications should be recorded using their trade 
name. 
All written information and other material to be used by patients and investigative staff must use 
vocabulary and language that are clearly understood. 

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12.6. 
Compensation for Injury 
The Sponsor maintains appropriate insurance coverage for clinical trials and will follow 
applicable local compensation laws.  Patients will be treated and/or compensated for any study-
related illness/injury in accordance with the information provided in the Compensation for Injury 
section of the Informed Consent document. 
 
 

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13. 
REFERENCES 
Altmann K-H, Dean NM, Fabbro D, et. al. Second generation of antisense oligonucleotides: From nuclease 
resistance to biological efficacy in animals. CHIMIA Int J Chem, 1996, 50: 168‑176. 
Crooke ST, Baker BF, Xia S, et. al. Integrated Assessment of the Clinical Performance of GalNAc3-Conjugated 2'-
O-Methoxyethyl Chimeric Antisense Oligonucleotides: I. Human Volunteer Experience. Nucleic Acid Ther, 2018, 
29: 16-32. 
Crooke ST and Bennett CF. Progress in antisense oligonucleotide therapeutics. Annu Rev Pharmacol Toxicol, 1996, 
36: 107-129. 
Geary RS, Yu RZ, Watanabe T, et. al. Pharmacokinetics of a tumor necrosis factor-alpha phosphorothioate 2'-O-(2-
methoxyethyl) modified antisense oligonucleotide: comparison across species. Drug Metab Dispos, 2003, 31: 1419-
1428. 
Henry S, Stecker K, Brooks D, et. al. Chemically modified oligonucleotides exhibit decreased immune stimulation 
in mice. J Pharmacol Exp Ther, 2000, 292: 468-479. 
Inoue H, Hayase Y, Iwai S, et. al. Sequence-dependent hydrolysis of RNA using modified oligonucleotide splints 
and RNase H. FEBS Lett, 1987, 215: 327-330. 
Karimi M, Haghpanah S, Azarkeivan A, et. al. Prevalence and mortality in β-thalassaemias due to outbreak of novel 
coronavirus disease (COVID-19): the nationwide Iranian experience. Br J Haematol, 2020, 190: e137-e140. 
McKay RA, Miraglia LJ, Cummins LL, et. al. Characterization of a potent and specific class of antisense 
oligonucleotide inhibitor of human protein kinase C-α expression. J Biol Chem, 1999, 274: 1715-1722. 
Monia BP, Lesnik EA, Gonzalez C, et. al. Evaluation of 2'-modified oligonucleotides containing 2'-deoxy gaps as 
antisense inhibitors of gene expression. J Biol Chem, 1993, 268: 14514-14522. 
Motta I, Migone De Amicis M, Pinto VM, et. al. SARS-CoV-2 infection in beta thalassemia: Preliminary data from 
the Italian experience. Am J Hematol, 2020, 95: E198-e199. 
Prakash TP, Graham MJ, Yu J, et. al. Targeted delivery of antisense oligonucleotides to hepatocytes using 
triantennary N-acetyl galactosamine improves potency 10-fold in mice. Nucleic Acids Res, 2014, 42: 8796-8807. 
Provan D, Stasi R, Newland AC, et. al. International consensus report on the investigation and management of 
primary immune thrombocytopenia. Blood, 2010, 115: 168-186. 
Schulman S and Kearon C. Definition of major bleeding in clinical investigations of antihemostatic medicinal 
products in non-surgical patients. J Thromb Haemost, 2005, 3: 692-694. 
Stockert RJ. The asialoglycoprotein receptor: relationships between structure, function, and expression. Physiol Rev, 
1995, 75: 591-609. 
Sturgeon P, Itano HA and Bergren WR. Genetic and biochemical studies of intermediate types of Cooley's anaemia. 
Br J Haematol, 1955, 1: 264-277. 
Taher A, Cappellini MD, Viprakasit V, et. al. Validation of a patient-reported outcomes symptom measure for 
patients with nontransfusion-dependent thalassemia (NTDT-PRO((c)) ). Am J Hematol, 2019, 94: 177-183. 
Taher A, Viprakasit V, Cappellini MD, et. al. Development of a patient-reported outcomes symptom measure for 
patients with nontransfusion-dependent thalassemia (NTDT-PRO((c)) ). Am J Hematol, 2019, 94: 171-176. 
Taher AT, Bou-Fakhredin R, Kreidieh F, et. al. Care of patients with hemoglobin disorders during the COVID-19 
pandemic: An overview of recommendations. Am J Hematol, 2020, 95: E208-E210. 
Tsimikas S, Karwatowska-Prokopczuk E, Gouni-Berthold I, et. al. Lipoprotein(a) Reduction in Persons with 
Cardiovascular Disease. N Engl J Med, 2020, 382: 244-255. 
Zhang H, Lowenberg EC, Crosby JR, et. al. Inhibition of the intrinsic coagulation pathway factor XI by antisense 
oligonucleotides: a novel antithrombotic strategy with lowered bleeding risk. Blood, 2010, 116: 4684-4692. 
 
 

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14. 
APPENDICES 
 

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APPENDIX A. SCHEDULE OF PROCEDURES 
 
Screening Period, Treatment Period, Early Termination from Treatment (ETFT) 
Post-Treatment Period (PTP) 
 

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Appendix A Schedule of Procedures – Screening Period, Treatment Period, & Early Termination from Treatment (ETFT)  
Period Name 
(Duration) 
Screening Period 
(8 Weeks) 
Treatment Period (104 Weeks) 
 
Visit Name 
SV1 SV2 SV3 SV4 
 
ETFT1 Transition 
to PTP 
Study Week 
-9 
-5 
-3 
-2 
1 
5 
9 
13 17 21 252 272 29 33 37 41 45 49 533 57 61 65 69 73 77 81 85 89 93 97 101 105 
 
 
Study Day 
-57 -29 -15 -8 
1 
29 57 85 113 141 16921832 197 225 253 281 309 337 3653 393 421 449 477 505 533 561 589 617 645 673 701 729 
 
 
Visit Window 
(Days) 
±7 ±7 ±2 ±2 
0 
±7 ±7 ±7 ±7 ±7 ±7 ±4 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 N/A 
N/A 
Clinic Visit4 
X 
X 
 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
 
Telephone 
Assessment5 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
 
 
 
ISIS 702843 
Administration6 
 
 
 
 
X 
X 
X 
X 
X 
X 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Informed Consent 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Inclusion/ 
Exclusion 
X 
 
 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Medical History 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Height 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Body Weight 
X 
 
 
 
X 
 
X 
 
X 
 
 
X  
 
X 
 
X  
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
Physical 
Examination7 
X 
 
 
 
X 
 
X 
 
X 
 
 
X 
 
X 
 
X 
 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
 
Vital Signs8 
X 
 
 
 
Xa Xa Xa Xa Xa 
 
 
X 
 
Xa 
 
Xa 
 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
X 
 
HIV, Hepatitis B & 
C9 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Alcohol Screen 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Pregnancy Test9,10 
X 
 
 
X 
X 
X 
X 
X 
X 
X 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
FSH9, 11 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Endocrine Panel9 
X 
 
 
 
 
 
 
 
 
 
 
X 
 
 
 
 
 
 
X 
 
 
 
 
 
X 
 
 
 
 
 
 
X 
X 
 
Chemistry Panel 
(Fasting)9, 12, 13 
X 
 
X 
 
Xa Xa Xa Xa Xa 
 
 
X  
 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
X 
 
Hematology9, 13, 14 
X 
X 
X 
X 
Xa Xa Xa Xa Xa Xa Xa X 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
X 
 
Urinalysis15 
X 
 
X 
 
Xa Xa Xa Xa Xa Xa Xa X 
Xa Xa Xa Xa Xa Xa Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa 
 
Xa Xa 
X 
 
 

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Appendix A. Schedule of Procedures – Screening Period, Treatment Period, & Early Termination from Treatment 
(ETFT) Continued 
Period Name 
(Duration) 
Screening Period 
(8 Weeks) 
Treatment Period (104 Weeks) 
 
Visit Name 
SV1 SV2 SV3 SV4 
 
ETFT1 Transition 
to PTP 
Study Week 
-9 
-5 
-3 
-2 
1 
5 
9 
13 17 21 252 272 29 33 37 41 45 49 533 57 61 65 69 73 77 81 85 89 93 97 101 105 
 
 
Study Day 
-57 
-29 -15 -8 
1 
29 57 85 113 141 16921832 197 225 253 281 309 337 3653 393 421 449 477 505 533 561 589 617 645 673 701 729 
 
 
Visit Window 
(Days) 
±7 
±7 ±2 ±2 
0 
±7 ±7 ±7 ±7 ±7 ±7 ±4 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 N/A 
N/A 
Iron Metabolism 
Panel, including 
TSAT and ferritin9, 
21 
X 
 
 
 
Xa 
 
 
 
Xa 
 
 
X 
 
 
Xa 
 
 
 
Xa 
 
 
 
Xa 
 
 
 
Xa 
 
 
 
Xa 
 
X 
 
TSAT9 
 
 
 
 
 
 
Xa 
 
 
 
 
 
 
 
 
 
Xa 
 
 
 
Xa 
 
 
 
Xa 
 
 
 
Xa 
 
 
 
 
 
Ferritin9 
 
 
 
 
 
Xa Xa Xa 
 
Xa Xa 
 
Xa Xa 
 
Xa Xa Xa 
 
 
Xa 
 
 
 
Xa 
 
 
 
Xa 
 
 
Xa 
 
 
Coagulation Panel9 
X 
 
X 
 
Xa 
 
 
Xa 
 
 
 
X 
 
 
 
 
 
 
Xa 
 
 
 
 
 
Xa 
 
 
 
 
 
 
 
X 
 
Archived Serum 
Sample9, 16 
 
 
 
 
Xa 
 
 
Xa 
 
 
 
X 
 
 
 
 
 
 
Xa 
 
 
 
 
 
Xa 
 
 
 
 
 
 
Xa 
X 
 
ECG (12-Lead), in 
triplicate 
X 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
 
 
 
 
X 
 
 
 
 
 
X 
 
 
 
 
 
 
X 
X 
 
Echocardiogram24 
X 
 
 
 
 
 
 
 
 
 
X 
 
 
 
 
 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
X 
X 
 
DEXA scan24 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
X 
X 
 
Adverse Events 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
Concomitant 
Medications 
X 
X 
X  X  
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
ADA9 
 
 
 
 
Xa 
 
 
Xa 
 
 
 
 
Xa 
 
 
Xa 
 
 
Xa 
 
Xa 
 
 
 
Xa 
 
 
 
Xa 
 
 
 
X 
 
Antiplatelet 
Antibodies9 
X 
 
 
 
 
 
 
Xa 
 
 
 
 
Xa 
 
 
 
 
 
Xa 
 
 
 
 
 
Xa 
 
 
 
 
 
 
 
X 
 
Platelet Function 
Testing9, 17  
 
X 
 
 
 
 
 
 
 
 
 
 
Xa 
 
 
 
 
 
Xa 
 
 
 
 
 
Xa 
 
 
 
 
 
 
 
X 
 
PK Blood 
Sampling9 
 
 
 
 
Xb Xa Xa Xa Xa Xa Xa X 
Xc 
 
 
Xa 
 
 
Xa 
 
Xa 
 
 
 
Xa 
 
 
 
Xa 
 
 
Xa 
X 
 
Genotypic analysis 
of globin genes9 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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Appendix A. Schedule of Procedures – Screening Period, Treatment Period, & Early Termination from Treatment 
(ETFT) Continued 
Period Name 
(Duration) 
Screening Period 
(8 Weeks) 
Treatment Period (104 Weeks) 
 
Visit Name 
SV1 SV2 SV3 SV4 
ETFT1 Transition 
to PTP 
Study Week 
-9 
-5 
-3 
-2 
1 
5 
9 
13 17 21 252 272 29 33 37 41 45 49 533 57 61 65 69 73 77 81 85 89 93 97 101 105 
Study Day 
-57 -29 -15 -8 
1 
29 57 85 113 141 1692 1832 197 225 253 281 309 337 3653 393 421 449 477 505 533 561 589 617 645 673 701 729 
Visit Window 
(Days) 
±7 ±7 ±2 ±2 
0 
±7 ±7 ±7 ±7 ±7 ±7 ±4 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 
N/A 
N/A 
MRI; liver, spleen, 
and bone marrow18 
X 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
X 
 
 
 
 
 
X 
 
 
 
 
 
 
 
X19 
 
Ultrasound; liver 
and spleen18 
X 
 
 
 
 
 
 
 
X 
 
 
 
X 
 
 
X 
 
 
 
 
 
X 
 
 
 
 
 
 
 
X19 
 
EPO9 
 
 
 
 
Xa 
 
 
Xa 
 
 
 
X 
 
 
 
Xa 
 
 
Xa 
 
Xa 
 
 
 
Xa 
 
 
 
Xa 
 
 
 
X 
 
sTfR19 
 
 
 
 
Xa 
 
 
Xa 
 
 
 
X 
 
 
 
Xa 
 
 
Xa 
 
Xa 
 
 
 
Xa 
 
 
 
Xa 
 
 
 
X 
 
GDF159, 20 
 
 
 
 
Xa 
 
 
 
 
 
 
X 
 
 
 
 
 
 
Xa 
 
 
 
 
 
Xa 
 
 
 
 
 
 
 
X 
 
Erythroferrone9 
 
 
 
 
Xa 
 
 
Xa 
 
 
 
X 
 
 
 
Xa 
 
 
Xa 
 
Xa 
 
 
 
Xa 
 
 
 
Xa 
 
 
 
X 
 
Haptoglobin9 
 
 
 
 
Xa 
 
 
 
 
 
 
X 
 
 
 
 
 
 
Xa 
 
 
 
 
 
Xa 
 
 
 
 
 
 
 
X 
 
Protoporphyrin-
IX9 
 
 
 
 
Xa 
 
 
 
 
 
 
X 
 
 
 
 
 
 
Xa 
 
 
 
 
 
Xa 
 
 
 
 
 
 
 
X 
 
Bone markers9 
 
 
 
 
Xa 
 
 
 
 
 
 
X 
 
 
 
 
 
 
Xa 
 
 
 
 
 
Xa 
 
 
 
 
 
 
 
X 
 
NTDT-PRO© 22 
X 
X 
 
 
X 
 
 
X 
 
 
 
X 
 
 
 
 
 
 
X 
 
 
 
 
 
X 
 
 
 
 
 
 
 
X 
 
SF-3622 
X 
X 
 
 
X 
 
 
 
 
 
 
X 
 
 
 
 
 
 
X 
 
 
 
 
 
X 
 
 
 
 
 
 
 
X 
 
PGIC22 
X 
X 
 
 
X 
 
 
X 
 
 
 
X 
 
 
 
 
 
 
X 
 
 
 
 
 
X 
 
 
 
 
 
 
 
X 
 
ISGA22 
X 
X 
 
 
X 
 
 
 
 
 
 
X 
 
 
 
 
 
 
X 
 
 
 
 
 
X 
 
 
 
 
 
 
 
X 
 
FACIT-Fatigue22 
X 
X 
 
 
X 
 
 
X 
 
 
 
X 
 
 
 
 
 
 
X 
 
 
 
 
 
X 
 
 
 
 
 
 
 
X 
 
6MWT with pulse 
oximetry23 
X 
X 
 
 
X 
 
 
X 
 
 
 
X 
 
 
 
 
 
 
X 
 
 
 
 
 
X 
 
 
 
 
 
 
 
X 
 
Note:  
If not specifically labeled, “X” means anytime 
 

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Appendix A. 
Schedule of Procedures – Screening Period, Treatment Period, & Early Termination from Treatment (ETFT) 
Continued 
Legend 
1 
Patients who discontinue ISIS 702843 treatment and agree to remain in the study will attend the following clinic visits:  ETFT, PTP Visit 1, PTP Visit 2, and 
PTP Last Visit.  If patient is unable or unwilling to participate in all of these visits, the PI should determine the follow-up procedures the patient would agree 
to complete.  Every effort should be made to complete the ETFT study procedures and observations at the time of withdrawal. 
2 
The columns for Day 169 (Week 25) and Day 183 (Week 27) are outlined with bolded lines because they are associated with the first interim analysis (see 
Section 10.5).  Note that there is no ISIS 702843 administration on Day 183 (Week 27).  The regular frequency of dosing – a planned 28-day interval 
between each dose – is maintained throughout the Treatment Period. 
3 
The column for Day 365 (Week 53) is outlined with bolded lines because it is associated with the second interim analysis (see Section 10.5). 
4 
When no Clinic Visit is scheduled (SV3, SV4, and Weeks 57, 65, 73, 81, 89, and 97), urine and, if needed, blood samples may be collected at Study Clinic, 
at a local phlebotomy clinic, or by a home healthcare provider, at PI discretion.  The testing should be done at the central laboratory except when Section 3.8 
applies, in which case a local laboratory is acceptable provided that the local laboratory results are recorded by the site into the electronic database. 
5 
The Study Center will conduct a phone call to check compliance and capture AEs or changes in concomitant medication usage. 
6 
ISIS 702843 will be administered every 4 weeks by 1 or 2 SC injection(s) (Section 8.1).  Unless the allowances in the circumstance of a public health 
emergency apply (Section 3.8), through Day 365 (Week 53) all doses will be administered at the Clinic, either by Study Center staff or by the trained 
patient/caregiver under the observation of Study Center staff.  After that visit – earlier if Section 3.8 applies – self-administration at home is allowed after 
appropriate training of patient/caregiver, with training related to the injection step itself encouraged to start as early as Day 1 (e.g., patient or caregiver 
observes the injection on Day 1 and performs the injection(s) under the observation of Study Center staff at subsequent visits).  In the absence of self-
administration training, ISIS 702843 will continue to be administered, with the planned interval between each dose remaining 28 days, either at the Study 
Center by delegated staff or via home visits by Study Center staff or home healthcare providers. 
7 
Full physical examination to be performed at Screening and abbreviated physical examination to be performed during the Treatment Period, as indicated, to 
assess changes from Screening. 
8 
BP, HR, RR, temperature. 
9 
Because the patients in this study have anemia, care should be taken to collect the minimum volume of blood needed to adequately support the intended 
test(s). Unless otherwise instructed by the PI, sampling tubes having the smallest practical volume will be used. 
10 
Women who are not surgically sterile or post-menopausal.  Urine test is acceptable after SV1, and is planned at time-points that do not have a scheduled 
blood sample for another purpose.  A serum test is planned at those visits that do require a blood sample for another purpose such as Chemistry Panel or 
Hematology.  A positive urine test is to be confirmed by a serum test. 
11 
FSH is performed in all patients at all scheduled events of Endocrine Panel (see Appendix B).  At SV1, FSH is also a Screening Test, with the FSH result 
used to address Inclusion Criterion 8 in women who are not surgically sterile, and who are potentially menopausal or post-menopausal. 
12 
Fasted samples should be taken after fasting for approximately 8-10 hours.  During this time the patient can drink water and they should ensure that they 
consume sufficient water to avoid dehydration.  Fasting is not required when tests are repeated for safety reasons. 
13 
If the platelet value, serum creatinine, or liver enzyme tests are uninterpretable (e.g., due to clumping, hemolysis, or quantity not sufficient) or missing, a 
repeat blood specimen should be re-drawn as soon as possible – ideally within 7 days, should be within 2 weeks – which may require an unscheduled visit or 
blood draw. 
 

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Appendix A. 
Schedule of Procedures – Screening Period, Treatment Period, & Early Termination from Treatment (ETFT) 
Continued 
Legend Continued 
14 
Multiple Hb measurements are required for both Screening eligibility and Baseline analysis.  Both Screening Mean Hb for Eligibility and Baseline Hb for 
Analysis are based on at least two Hb measurements, all of which must be taken at least 6 weeks after the most recent transfusion for that patient.  
See Section 6.1.1. 
15 
If proteinuria is observed, confirm the result and follow Section 8.6.5. 
16 
Stored at -80 °C for exploration of laboratory findings, safety concerns, and/or AEs (e.g., measurement of cytokine and/or chemokine levels, measurement of 
additional markers of kidney function, measurement of antibodies, etc.) in this or subsequent clinical studies of ISIS 702843. 
17 
It is preferred that the patient has not taken aspirin or NSAIDs (nonsteroidal anti-inflammatory drugs) throughout the 72 hours before this test, however 
clinical judgment by the PI should be used in deciding to withhold these drugs.  Document on the ConMed CRF any use of aspirin, NSAIDS, or anti-platelet 
inhibitors [P2Y12 Inhibitors such as clopidogrel (Plavix), prasugrel (Effient), and ticagrelor (Brilinta)].  This test will not be performed with all patients 
because this test should be performed with fresh blood, and proximity to suitable equipment is not practical with some clinical sites. 
18 
In regards to Inclusion Criterion 6, MRI and Ultrasound may be performed anytime within the Screening Period; however, it is preferred for these 
evaluations to be performed once the patient has met all other Inclusion/Exclusion Criteria, with the exception of Inclusion Criterion 5 because this criterion 
is evaluated based on all Hb measurements taken in the Screening Period, as described in Footnote 14, above.  In the Screening Period and at all applicable 
time-points in the Treatment Period, MRI and Ultrasound should be conducted within one week of one another – ideally on the same day. 
19 
To be done within 4 weeks of the ETFT visit. 
20 
This test may not be performed, so sample will be stored frozen; if this test is performed, it may not be performed with all patients. 
21 
Sampling time for serum hepcidin testing – a component of the Iron Metabolism Panel – is preferably at the same time of day from one occurrence to the 
next for a given patient; ideally, this consistent sampling time will be in the morning. 
22 
Preferably, this survey should be completed before ISIS 702843 administration.  If survey is completed after the ISIS 702843 administration at that clinic 
visit, this will not be considered a protocol deviation that will impact efficacy. 
23 
Preferably, the 6MWT with pulse oximetry should be completed before ISIS 702843 administration.  If the 6MWT with pulse oximetry is completed after 
the ISIS 702843 administration at that clinic visit, this will not be considered a protocol deviation that will impact efficacy. 
24 
Within the Screening Period, Echocardiogram and DEXA scan may be performed anytime through SV2. 
 
Time (in reference to ISIS 702843 administration): 
a 
Pre-dose 
b 
Pre-dose, and 1, 2, 4, 6 hour post-dose 
c 
Pre-dose, and 3 hour post-dose 
 
 
 

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Appendix A Schedule of Procedures – Post-Treatment Period (PTP) 
Period Name (Duration) 
Post-Treatment Period (131 Weeks) 
Visit Name 
PTP Visit 1 
PTP Visit 2 
PTP Last Visit 
Week within the PTP 
PTP Week 52 
PTP Week 9 
PTP Week 14 
Day within the PTP 
PTP Day 292 
PTP Day 57 
PTP Day 92 
Study Day from Day 13 
757 
785 
820 
Visit Window (Days) 
±7 
±7 
±7 
Clinic Visit 
X 
X 
X 
Body Weight 
X 
 
X 
Physical Examination4 
X 
 
X 
Vital Signs5 
X 
 
X 
Pregnancy Test6, 7 
X 
X 
X 
Chemistry Panel (Fasting)6, 8, 9 
X 
X 
X 
Hematology6, 9 
X 
X 
X 
Urinalysis10 
X 
X 
X 
Iron Metabolism Panel, including 
TSAT and Ferritin6, 16 
X 
X 
X 
Coagulation Panel6 
X11 
 
 
Archived Serum Sample6, 12 
X 
 
X 
Adverse Events 
X 
X 
X 
Concomitant Medications 
X 
X 
X 
ADA6 
X11 
X 
X 
Antiplatelet Antibodies6 
X11 
 
 
Platelet Function Testing6, 15 
X 
 
 
PK Blood Sampling6 
X 
X 
X 
MRI; liver, spleen, and bone marrow13 
X11 
 
 
Ultrasound; liver and spleen13 
X11 
 
 
EPO6 
X11 
 
X 
sTfR16 
X11 
 
X 
GDF156, 14 
X11 
 
X 
Erythroferrone6 
X11 
 
X 
Haptoglobin6 
X11 
 
X 
Protoporphyrin-IX6 
X11 
 
X 
Bone markers6 
X11 
 
X 
NTDT-PRO© 
X11 
 
X 
SF-36 
X11 
 
X 

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Appendix A Schedule of Procedures – Post-Treatment Period (PTP) Continued 
Period Name (Duration) 
Post-Treatment Period (131 Weeks) 
Visit Name 
PTP Visit 1 
PTP Visit 2 
PTP Last Visit 
Week within the PTP 
PTP Week 52 
PTP Week 9 
PTP Week 14 
Day within the PTP 
PTP Day 292 
PTP Day 57 
PTP Day 92 
Study Day from Day 13 
757 
785 
820 
Visit Window (Days) 
±7 
±7 
±7 
PGIC 
X11 
 
X 
ISGA 
X11 
 
X 
FACIT-Fatigue 
X11 
 
X 
6MWT with pulse oximetry 
X11 
 
X 
Note:  
If not specifically labeled, “X” means anytime 
Legend 
1 
This includes the 4 weeks since the last dose in the Treatment Period 
2 
PTP Day 1 (Week 1) is equivalent in time to Day 729 (Week 105) of the Treatment Period, or the ETFT visit.  There are 4 weeks between PTP Day 1 
(Week 1) and PTP Visit 1 
3 
In this table, the values provided for “Study Day from Day 1” are only accurate for those patients who do not discontinue from ISIS 702843 treatment 
4 
Abbreviated physical examination to be performed during the PTP, as indicated, to assess changes from Screening 
5 
BP, HR, RR, temperature 
6 
Because the patients in this study have anemia, care should be taken to collect the minimum volume of blood needed to adequately support the intended 
test(s).  Unless otherwise instructed by the PI, sampling tubes having the smallest practical volume will be used 
7 
Women who are not surgically sterile or post-menopausal.  Urine test is acceptable throughout the PTP, although a serum test is planned, using a blood 
sample collected for another purpose such as Chemistry Panel or Hematology.  A positive urine test is to be confirmed by a serum test 
8 
Fasted samples should be taken after fasting for approximately 8-10 hours.  During this time the patient can drink water and they should ensure that they 
consume sufficient water in order to not become dehydrated.  Fasting is not required when tests are repeated for safety reasons 
9 
If the platelet value, serum creatinine, or liver enzyme tests are uninterpretable (e.g., due to clumping, hemolysis, or quantity not sufficient) or missing, a 
repeat blood specimen should be re-drawn as soon as possible – ideally within 7 days, should be within 2 weeks – which may require an unscheduled visit or 
blood draw 
10 
If proteinuria is observed, confirm the result and follow Section 8.6.5  
11 
Not needed, if done at ETFT 
12 
Stored at -80 °C for exploration of laboratory findings, safety concerns, and/or AEs (e.g., measurement of cytokine and/or chemokine levels, measurement of 
additional markers of kidney function, measurement of antibodies, etc.) in this or subsequent clinical studies of ISIS 702843 
13 
MRI and Ultrasound should be conducted within 1 week of one another – ideally on the same day 
14 
This test may not be performed, so sample will be stored frozen; if this test is performed, it may not be performed with all patients 
 
 

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Appendix A Schedule of Procedures – Post-Treatment Period (PTP) Continued 
Legend Continued 
15 
It is preferred that the patient has not taken aspirin or NSAIDs (nonsteroidal anti-inflammatory drugs) throughout the 72 hours before this test, however 
clinical judgment by the PI should be used in deciding to withhold these drugs.  Document on the ConMed CRF any use of aspirin, NSAIDS, or anti-platelet 
inhibitors [P2Y12 Inhibitors such as clopidogrel (Plavix), prasugrel (Effient), and ticagrelor (Brilinta)].  This test will not be performed with all patients 
because this test should be performed with fresh blood, and proximity to suitable equipment is not practical with some clinical sites 
16 
Sampling time for serum hepcidin testing – a component of the Iron Metabolism Panel – is preferably at the same time of day from one occurrence to the 
next for a given patient; ideally, this consistent sampling time will be in the morning 

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APPENDIX B. List of Laboratory Tests 
 
 

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Appendix B List of Laboratory Tests 
Based on emerging data from this or future studies, additional tests not listed below may be 
performed on stored samples to better characterize the profile of ISIS 702843 or other similar 
oligonucleotides. 
Clinical Chemistry Panel 
• Calcium1 
• Phosphorus1 
• Alkaline phosphatase 
(ALP)1 
• Sodium 
• Potassium 
• Chloride 
• Bicarbonate 
• Total protein 
• Albumin 
• Magnesium 
• Glucose (FBS) 
• BUN 
• Creatinine 
• Uric acid 
• Total bilirubin 
• Direct (conjugated) 
bilirubin 
• Indirect (unconjugated) 
bilirubin 
• ALT 
• AST 
• Creatinine kinase 
• GGT 
• LDH 
 
Bone Markers 
• Calcium1 
• Phosphorus1 
• ALP1 
• Parathyroid hormone 
• Vitamin D 
Screening Tests 
• Hepatitis B surface antigen 
• Hepatitis C antibody 
• HIV antibody 
• FSH2 
• Serum βhCG 
• Alcohol Screen 
 
Coagulation Panel 
• PT 
• INR 
• aPTT 
• Antithrombin III 
• Protein S 
• Protein C 
 
Iron Metabolism Panel 
• Serum hepcidin 
• Serum iron 
• Serum transferrin 
• Serum ferritin 
• TSAT 
• NTBI 
 
Platelet Count Safety Panel4 
• Peripheral smear 
• Fibrinogen split products 
or D-dimer on fresh blood 
• Citrated sample for platelets 
• Coagulation panel (PT/INR, 
aPTT) 
• CBC with reticulocytes and 
mean platelet volume 
• Total globulins: IgG and 
IgM 
• Complement: total C3, total 
C4, C5a 
• Serology for hepatitis B 
virus, HCV, HIV (if not 
done recently for Screening) 
• Antiplatelet antibodies 
• ADA 
Hematology Panel 
• RBC count 
• Hb 
• Hematocrit 
• RDW 
• MCV, MCH, MCHC 
• Erythroblast count 
• Reticulocyte count 
• Platelet count 
• White blood cell count 
• WBC differential (% 
and absolute) 
• Peripheral blood smear 
• CHr3 
 
Endocrine Panel 
• TSH 
• Free T4 
• Free T3 
• FSH2 
• LH 
• Testosterone (men only) 
 
Pharmacokinetics 
• ISIS 702843 levels in 
plasma5 
 
Immunogenicity 
• Anti-ISIS 702843 
antibodies (i.e., anti-
drug antibodies [ADA])5 
 
Urinalysis 
• Color 
• Appearance 
• Specific gravity 
• pH 
• UPCR 
• Protein 
• Blood 
• Ketones 
• Urobilinogen 
• Glucose 
• Bilirubin 
• Leukocyte esterase 
• Nitrate 
• Microscopic 
examination6 
 
Other 
• EPO 
• sTfR1 
• GDF15 
• Erythroferrone 
• Haptoglobin 
• Protoporphyrin-IX 
• Platelet function 
testing 
• Genotypic analysis 
of globin genes  
(included in the 
genetic assessment of 
a panel of blood-
related disorders) 
 

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Appendix B. List of Laboratory Tests Continued 
Legend 
1 
Calcium, Phosphorus, and ALP are performed at all scheduled events of Clinical Chemistry Panel.  At a subset of 
these events, Bone Markers are also evaluated.  At these time-points, the Calcium, Phosphorus, and ALP results from 
Clinical Chemistry Panel are also applicable to Bone Markers. 
2 
FSH is performed in all patients at all scheduled events of Endocrine Panel.  At SV1, FSH is also a Screening Test, 
with the FSH result used to address Inclusion Criterion 8 in women who are not surgically sterile, and who are 
potentially menopausal or post-menopausal. 
3 
Either traditional CHr or “reticulocyte hemoglobin equivalent” (i.e., run on Sysmex machines), ideally being 
consistent with respect to which type of machine is used intra-patient, and reporting as percent change 
4 
These tests should be done if a patient has a platelet count < 50,000/mm3 (Section 8.5.2). 
5 
Plasma samples may also be used for profiling of drug binding proteins, bioanalytical method validation purposes, 
stability assessments, metabolite assessments, immunogenicity testing (or possibly for purposes of immunogenicity 
assay development and/or validation), or to assess other actions of ISIS 702843 with plasma constituents. 
6 
Will be performed on abnormal findings unless otherwise specified.

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Appendix C. 
PK Sampling Schedule 
Treatment Period and Early Termination from Treatment (ETFT) 
Post-Treatment Period (PTP) 
 

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Appendix C PK Sampling Schedule 
Treatment Period and Early Termination from Treatment (ETFT) 
Time Points for PK Blood Draws 
Week 1 
Week  
5 
Week  
9 
Week  
13 
Week  
17 
Week  
21 
Week 
25 
Week 
27 
Week 
29 
Week  
41 
Week 
 53 
Week  
61 
Week  
77 
Week  
93 
Week  
105 
ETFT 
Day 1 
Day 29 Day 57 Day 85 Day 113 Day 141 Day 169 Day 183 Day 197 Day 281 Day 365 Day 421 Day 533 Day 645 Day 729 
Pre-dose, 
and 1, 2, 4, 
and 6 hour 
post-dose 
Pre-dose Pre-dose Pre-dose Pre-dose Pre-dose Pre-dose Anytime 
Pre-dose 
 and 3-hour 
post-dose 
Pre-dose Pre-dose Pre-dose Pre-dose Pre-dose Pre-dose Anytime 
Number of PK Blood Draws 
5 
1 
1 
1 
1 
1 
1 
1 
2 
1 
1 
1 
1 
1 
1 
1 
Note:  Time is shown as hours relative to dose of ISIS 702843 
 
Post-Treatment Period (PTP) 
Time Points for PK Blood Draws 
PTP Visit 1 
PTP Visit 2 
PTP Last Visit 
PTP Week 5 
PTP Week 9 
PTP Week 14 
PTP Day 29 
PTP Day 57 
PTP Day 92 
Anytime 
Anytime 
Anytime 
Number of PK Blood Draws 
1 
1 
1 

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APPENDIX D. Grading Scale For Adverse Events Relating To Laboratory 
Abnormalities 
 
 

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Appendix D Grading Scale for Adverse Events Relating to Laboratory Abnormalities 
The following grading recommendations for adverse events relating to laboratory test 
abnormalities and adverse events at the injection site are based on the Common Terminology 
Criteria for Adverse Events (CTCAE) Version 5.0, November 2017.  The severity of AEs and 
SAEs relating to laboratory tests and adverse events at the injection site may be graded based on 
these criteria. 
Alternatively, the Investigator should classify events and laboratory findings as mild, moderate, 
or severe based on the clinical significance of the event and laboratory finding for that patient, 
for example, laboratory findings related to Hb, ALT, and AST. 
Any AE not listed below will be graded as described in Section 9.4.3.2  
 

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Appendix D. Grading Scale For Adverse Events Relating To Laboratory Abnormalities 
Continued 
 

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Appendix D. Grading Scale For Adverse Events Relating To Laboratory Abnormalities 
Continued 
 
 
 

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APPENDIX E. Measures of Quality of Life & Functional Status of the 
Patient 
NTDT-PRO© 
SF-36 
PGIC 
ISGA 
FACIT-Fatigue 
6MWT 
 

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Appendix E Measures of Quality of Life & Functional Status of the Patient 
NTDT-PRO© (“Non-transfusion Dependent Thalassemia-Patient Reported Outcome©) 
The following NTDT-PRO© has been published – see 2 citations below – and is used by 
permission. 
• Development of a patient-reported outcomes symptom measure for patients with 
nontransfusion-dependent thalassemia (NTDT-PRO©). 
(Taher, Viprakasit, et al. 2019) 
• Validation of a patient-reported outcomes symptom measure for patients with 
nontransfusion-dependent thalassemia (NTDT-PRO©). 
(Taher, Cappellini, et al. 2019) 
NTDT-PRO©.v2 (version 2) Instrument 
 
For each of the following questions, please choose the number that best describes the 
symptoms that you may have experienced during the past 24 hours. 
1.  How would you rate your tiredness (lack of energy) when you were not doing physical activity 
during the past 24 hours? 
 
0 
 
1 
 
2 
 
3 
 
4 
 
5 
 
6 
 
7 
 
8 
 
9 
 
10 
No 
tiredness 
 
 
 
 
 
 
 
 
 
Extreme 
tiredness 
2. How would you rate your tiredness (lack of energy) when you were doing physical activity 
during the past 24 hours? 
 
0 
 
1 
 
2 
 
3 
 
4 
 
5 
 
6 
 
7 
 
8 
 
9 
 
10 
No 
tiredness 
 
 
 
 
 
 
 
 
 
Extreme 
tiredness 
3.  How would you rate your weakness (lack of strength) when you were not doing physical 
activity during the past 24 hours? 
 
0 
 
1 
 
2 
 
3 
 
4 
 
5 
 
6 
 
7 
 
8 
 
9 
 
10 
No 
weakness 
 
 
 
 
 
 
 
 
 
Extreme 
weakness 
4.  How would you rate your weakness (lack of strength) when you were doing physical activity 
during the past 24 hours? 
 
0 
 
1 
 
2 
 
3 
 
4 
 
5 
 
6 
 
7 
 
8 
 
9 
 
10 
No 
weakness 
 
 
 
 
 
 
 
 
 
Extreme 
weakness 
 
 

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Appendix E: Measures of Quality of Life & Functional Status of the Patient Continued 
NTDT-PRO Continued 
5. How would you rate your shortness of breath when you were not doing physical activity during the 
past 24 hours? 
 
0 
 
1 
 
2 
 
3 
 
4 
 
5 
 
6 
 
7 
 
8 
 
9 
 
10 
No 
shortness 
of breath 
 
 
 
 
 
 
 
 
 
Extreme 
shortness of
breath 
6.  How would you rate your shortness of breath when you were doing physical activity during the 
past 24 hours? 
 
0 
 
1 
 
2 
 
3 
 
4 
 
5 
 
6 
 
7 
 
8 
 
9 
 
10 
No 
shortness 
of breath 
 
 
 
 
 
 
 
 
 
Extreme 
shortness 
of breath 
For validation purposes only 
7.  During the past 24 hours, how would you rate the overall severity of your thalassemia symptoms? 
 
0 
 
1 
 
2 
 
3 
 
4 
 
5 
 
6 
 
7 
 
8 
 
9 
 
10 
No 
symptoms 
 
 
 
 
 
 
 
 
 
Very 
severe 
symptoms 
For validation purposes only (administered once every 3 weeks) 
8.  How would you rate the overall change in your thalassemia symptoms since the start of this study? 
□  A great deal better 
□  Much better 
□  A little better 
□  No change 
□  A little worse 
□  Much worse 
□  A great deal worse 
 
 

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Appendix E: Measures of Quality of Life & Functional Status of the Patient Continued 
SF-36 
 
 
 

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Appendix E: Measures of Quality of Life & Functional Status of the Patient Continued 
SF-36 Continued 
 
 
 

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Appendix E: Measures of Quality of Life & Functional Status of the Patient Continued 
SF-36 Continued 
 
 
 

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Appendix E: Measures of Quality of Life & Functional Status of the Patient Continued 
SF-36 Continued 
 

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Appendix E: Measures of Quality of Life & Functional Status of the Patient Continued 
SF-36 
Continued
 
 
 

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Appendix E: Measures of Quality of Life & Functional Status of the Patient Continued 
SF-36 Continued 

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Appendix E: Measures of Quality of Life & Functional Status of the Patient Continued 
Patient Global Impression of Change (PGIC) 
PATIENT GLOBAL IMPRESSION OF CHANGE (PGIC) 
Since the start of the study, my overall status is: 
✓ one box only: 
(1) □  Very Much Improved 
(2) □  Much Improved 
(3) □  Minimally Improved 
(4) □  No Change 
(5) □  Minimally Worse 
(6) □  Much Worse 
(7) □  Very Much Worse 
(US/English) 
 
 
 
 
 
 
 
 
 
 
 
USA/English – Version of 05 April 2005 
PGI-C_TS1.0_ID2036-2387_eng-USori.doc 
 

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Appendix E: Measures of Quality of Life & Functional Status of the Patient Continued 
6-Minute Walk Test (6MWT) - Borg CR10 Scale for Dyspnea and Fatigue 
 

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Appendix E: Measures of Quality of Life & Functional Status of the Patient Continued 
6MWT Continued – Borg CR10 Scale for Dyspnea and Fatigue Continued 
 

Version: 1
Version Date: 17 May 2021
Title: Protocol Amendment 2: A Phase 2a, Randomized, Open-Label Study to Evaluate the
Efficacy, Safety, Tolerability, PK and PD of ISIS 702843 Administered SC to
Patients with Non-Transfusion Dependent β-Thalassemia Intermedia
Protocol

 
 
 
 
 
 
 
 
 
 
Statistical Analysis Plan 
 
 
ISIS 702843-CS2 
 
A Phase 2a, Randomized, Open-Label Study to Evaluate the 
Efficacy, Safety, Tolerability, Pharmacokinetics and 
Pharmacodynamics of ISIS 702843 Administered Subcutaneously 
to Patients with Non-Transfusion Dependent β-Thalassemia 
Intermedia 
 
 
 
Date:  22 May 2023 
 
Version:  3.0 
 
 
 
 
 
 
 
 
 
 

Ionis Pharmaceuticals, Inc. 
CONFIDENTIAL 
22 May 2023
Statistical Analysis Plan 
ISIS 702843-CS2
 
Page 2 of 34 
SIGNATURES 
 
Ionis Pharmaceuticals, Inc. 
2855 Gazelle Court Carlsbad, CA 92010 
 
Compound Name:   TMPRSS6-L (ISIS 702843) Sapablursen 
 
Protocol:   
 ISIS 702843-CS2 
 
Study Title:   
A Phase 2a, Randomized, Open-Label Study to Evaluate the Efficacy, 
Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of 
ISIS 702843 Administered Subcutaneously to Patients with 
Non-Transfusion Dependent β-Thalassemia Intermedia 
 
Issue Date:    
22 May 2023 
 

Ionis Pharmaceuticals, Inc. 
CONFIDENTIAL 
22 May 2023
Statistical Analysis Plan 
ISIS 702843-CS2
 
Page 3 of 34 
Table of Contents 
REVISION HISTORY ................................................................................................................. 5 
ABBREVIATIONS ....................................................................................................................... 7 
1. 
INTRODUCTION  ................................................................................................................ 9 
1.1 
Study Overview .......................................................................................................................... 9 
1.2 
Objectives ................................................................................................................................. 10 
1.2.1 
Primary Objective ................................................................................................................................ 10 
1.2.2 
Secondary Objectives .......................................................................................................................... 11 
1.2.3 
Exploratory Objectives ........................................................................................................................ 11 
1.2.4 
Safety Objectives ................................................................................................................................. 11 
1.2.5 
Pharmacokinetic objectives ................................................................................................................. 12 
1.3 
Endpoints.................................................................................................................................. 12 
1.3.1 
Primary Endpoint ................................................................................................................................. 12 
1.3.2 
Secondary Endpoints ........................................................................................................................... 12 
1.3.3 
Exploratory Endpoints ......................................................................................................................... 12 
1.3.4 
Safety Endpoints .................................................................................................................................. 13 
1.3.5 
Pharmacokinetic Endpoints ................................................................................................................. 13 
2 
PROCEDURES ................................................................................................................... 13 
2.1 
General Overview of Procedures ........................................................................................... 13 
2.2 
Randomization & Treatment Allocation ............................................................................... 13 
2.3 
Conduct .................................................................................................................................... 14 
2.4 
Data Monitoring ...................................................................................................................... 14 
2.4.1 
Safety Data Monitoring ....................................................................................................................... 14 
2.4.2 
Data Monitoring Board ........................................................................................................................ 14 
2.5 
Data Management ................................................................................................................... 14 
2.5.1 
Case Report Form Data ........................................................................................................................ 14 
2.5.2 
Laboratory Data ................................................................................................................................... 15 
2.5.3 
Pharmacokinetics Data ........................................................................................................................ 15 
2.5.4 
Immunogenicity (IM) Analysis ............................................................................................................ 15 
3 
ANALYTICAL PLAN ........................................................................................................ 16 
3.1 
Statistical Design Summary .................................................................................................... 16 
3.2 
General Overview of Analyses ................................................................................................ 16 
3.2.1 
Statistical Methods ............................................................................................................................... 16 
3.2.2 
Subject Population Analyzed ............................................................................................................... 18 
3.3 
Primary Analysis ..................................................................................................................... 19 
3.3.1 
Primary Endpoint Definition................................................................................................................ 19 
3.3.2 
Analysis of Primary Endpoint .............................................................................................................. 19 
3.3.3 
Sample Size Consideration .................................................................................................................. 19 
3.3.4 
Planned Interim Analyses .................................................................................................................... 19 
3.3.5 
Incomplete or Missing Data ................................................................................................................. 20 
3.4 
Secondary Analyses ................................................................................................................. 20 
3.4.1 
Secondary Endpoint Definitions .......................................................................................................... 20 
3.4.2 
Analysis of Secondary Endpoints ........................................................................................................ 20 

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Statistical Analysis Plan 
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3.5 
Exploratory Analyses .............................................................................................................. 21 
3.6 
Pharmacokinetic (PK) and Immunogenicity (IM) Analysis ................................................ 21 
3.6.1 
Plasma Concentration Data of Total Full-Length Oligonucleotides .................................................... 22 
3.6.2 
Plasma Pharmacokinetic Parameters ................................................................................................... 22 
3.6.3 
Pharmacokinetic/Pharmacodynamic Exposure-Response Analysis .................................................... 23 
3.6.4 
IM Analysis ......................................................................................................................................... 23 
3.7 
Safety Analyses ........................................................................................................................ 27 
3.7.1 
Adverse Events .................................................................................................................................... 27 
3.7.2 
Vital Signs Measurements ................................................................................................................... 30 
3.7.3 
Laboratory Measurements ................................................................................................................... 30 
3.7.4 
Exposure and Drug Administration ..................................................................................................... 31 
3.7.5 
12-Lead Electrocardiograms (ECG) .................................................................................................... 32 
3.7.6 
Prior and Concomitant Medications .................................................................................................... 32 
3.7.7 
MRI ...................................................................................................................................................... 32 
3.7.8 
Genetic Sample .................................................................................................................................... 32 
4 
REFERENCES .................................................................................................................... 33 
REVISION SUMMARY ............................................................................................................ 34 

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22 May 2023
Statistical Analysis Plan 
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Page 5 of 34 
REVISION HISTORY 
Version No. 
Effective Date 
Summary of Changes 
V1.0 
30 Jun 2020 
The original SAP. 
V1.1 
13 Jul 2020 
Removed the signature page and updated the page number. The sign-
off process was conducted via Veeva system. 
V2.0 
23 Jul 2021 
1.  Updated Section 1.1 to incorporate changes of dosing amount, 
randomization, enrolment, and sample size per Protocol 
Amendment 2. 
2.  Changed the section number of Safety Objectives and Safety 
Endpoints to match the order with protocol. 
3.  Updated Section 2.2 to clarify the randomization scheme in the 
original Protocol, Protocol Amendment 1 and 2. Specified that 
the dosing amount increased to 120 mg per dose for Cohort A and 
B, and to 120 mg per dose for 3 consecutive doses, followed by 
160 mg per dose for Cohort C. 
4. Updated Section 3.1 to specify the total number of patients 
enrolled changed from 36 to 24. 12 patients will be enrolled for 
Cohort A and B; and 12 patients will be enrolled for Cohort C. 
5. Updated Section 3.2.7 to add 6-minute walk test with Pulse 
Oximetry. 
6. Updated Section 3.3.2 to change the number of patients required 
for interim analysis per Protocol Amendment 2. 
7.  Updated Section 3.3.3 to clarify the changes of enrollment 
process per Protocol Amendment 2. 
8.  Updated Section 3.4 to add analytical considerations regarding 
Hb measurements. 
9. Updated Section 3.7.3 to add analytical considerations for local 
lab performed due to COVID-19 public health emergency. 
10. Removed the description related to COVID-19 public health 
emergency in Section 3.2.1. Rephrased the description and added 
it in Section 3.2.5.  
11. Added Section 3.2.5 and 3.2.6 to provide more analytical 
considerations for COVID-19 public health emergency. 
Reorganized the section number of Section 3.2.5 – 3.2.8. 
12. Added the list of parameters used for correlation analysis and 
specify the details of time-to-event analysis in Section 3.5. 
13. Added Section 2.5.4 to clarify the details of Anti-Drug Antibody 
sample data. 
14. Added Section 3.7.8, 3.7.9 and 3.7.10 to specify analytical 
considerations regarding Ultrasound, MRI, Leg Ulcer, and 
Genetic sample. 
15. Added imputation rules for missing/partial date of adverse events 
and prior/concomitant medications. 
 
 

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Version No. 
Effective Date 
Summary of Changes 
V3.0 
18 May 2023 
1. Updated the whole document with the new SAP template. 
2. Added the Abbreviation Section. 
3. Updated Section 1.3 Endpoints to remove the exploratory 
endpoints listed below for the final analyses, because the Sponsor 
terminated the study due to a lack of efficacy and the CSR will be 
abbreviated:  
• Change from baseline of erythroblast count 
• Change from baseline of spleen iron concentration, and non-
transferrin bound iron (NTBI) 
• Change from baseline of plasma haptoglobin, plasma 
protoporphyrin IX, and blood smears 
• Change from baseline of antithrombin III, Protein S, and 
Protein C 
• Change from baseline on quality of life measures, including 
change from baseline in NTDT-PRO©, SF-36, PGIC, ISGA, 
and FACIT-Fatigue 
• Change from baseline on functional status of patient using 
6MWT instrument 
4. Updated Section 1.2 Objectives.  
5. Updated Section 3.2.1 Statistical Design Summary, COVID-19 
related information is in section COVID-19 Related Impact 
within Section 3.2.1 instead of Section 3.2.6.  
6. Moved Section 3.2.3 Disposition of Subjects, Section 3.2.4 
Demographic and Baseline Characteristics, and Section 3.2.5 
COVID-19 Related Impact to Section 3.2.1 Statistical Design 
Summary. 
7. Moved Section 3.2.6 Handling of Missing Data to Section 3.7.1 
Adverse Events. 
8. Removed Section 3.2.7 Measures of Questionnaires from the 
Quality of Life (QoL) and Functional Status. 
9. Updated Section 3.3.2 Analysis of Primary Endpoint to remove 
the description of potential additional comparison between 
cohorts. 
10. Updated Section 3.3.4 Planned Interim Analyses to clarify that 
formal interim analyses were not performed.  
11. Updated Section 3.5 Exploratory Analyses to remove correlation 
analysis, time to event analysis, and QoL related analysis. 
12. Updated Section 3.5 Exploratory Analyses to clarify some 
exploratory endpoints will not be analyzed.   
13 Updated Section 3.7 Safety Analyses to remove Echocardiogram 
and DEXA, Ultrasound and MRI assessment for spleen, and bone 
marrow, and Leg Ulcers.   
14. Updated Section 3.7.4 Exposure and Drug Administration to add 
additional exposure summary.  
 

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ABBREVIATIONS 
Abbreviation 
Definition 
ADA 
anti-drug antibodies 
AE 
adverse event 
ALT 
alanine aminotransferase (formerly referred to as serum glutamic pyruvic 
transaminase [SGPT]) 
aPTT 
activated partial thromboplastin time 
AST 
aspartate aminotransferase (formerly referred to as serum glutamic 
oxaloacetic transaminase [SGOT]) 
CHr 
reticulocyte hemoglobin content 
CRF 
case report form 
CSR 
clinical study report 
DEXA 
dual energy X-ray absorptiometry 
ECG 
electrocardiogram 
eCRF 
electronic Case Report Form 
EDC 
electronic data capture 
EPO 
erythropoietin 
ETFT 
early termination from treatment 
FACIT 
Functional Assessment of Chronic Illness Therapy 
FAS 
Full Analysis Set 
Fe/g 
iron (Fe) per gram of dry weight of liver 
GCP 
Good Clinical Practice 
GDF15 
growth differentiation factor 15 
Hb 
hemoglobin 
ICH 
International Conference on Harmonization 
IE 
ineffective erythropoiesis 
INR 
international normalized ratio 
IRT 
Interactive Response Technology 
ISGA 
Investigator’s Static Global Assessment 
ISIS 702843 
antisense inhibitor of TMPRSS6 
LDH 
lactate dehydrogenase 
LIC 
liver iron concentration 
MCH 
mean corpuscular hemoglobin (amount) 
MCHC 
mean corpuscular hemoglobin concentration 
MCV 
mean corpuscular volume 
MedDRATM 
Medical Dictionary for Regulatory Activities  
MRI 
magnetic resonance imaging 
NTBI 
non-transferrin-bound iron 
NTDT 
non-transfusion dependent thalassemia 
on study 
The patient is ‘on study’ from signing of the informed consent until their 
last study visit 
PD 
pharmacodynamic(s) 
PGIC 
Patient Global Impression of Change 
PHT 
pulmonary hypertension 

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Abbreviation 
Definition 
PI 
Principal Investigator 
PK 
pharmacokinetic(s) 
PRO 
patient-reported outcome(s) 
PT 
prothrombin time 
PTP 
post-treatment period 
RBC 
red blood cell(s) 
SAE 
serious adverse event 
SAP 
Statistical Analysis Plan 
SC 
subcutaneous(ly) 
SOC 
System Organ Classes 
sTfR1 
soluble transferrin receptor 1 
Study Day 1 
defined as the first day ISIS 702843 is administered to the patient 
Study Drug 
ISIS 702843 (there is no placebo in this study) 
TEAE 
treatment-emergent adverse event 
TMPRSS6 
transmembrane protease, serine 6 
TSAT 
transferrin saturation 
ULN 
upper limit of normal 

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1.0 INTRODUCTION 
This document provides a description of the statistical methods and procedures to be 
implemented for the analyses of data from Ionis Pharmaceuticals, Inc. study with Protocol 
Number ISIS 702843-CS2.  Section 1 discusses study design, objectives, and endpoints; 
Section 2 provides the study procedures; Section 3 provides the detailed plan for the statistical 
analyses. 
The purpose of this plan is to provide specific guidelines from which the analysis will proceed.  
Any deviations from these guidelines will be documented in the clinical study report (CSR).  
Within this document, the terms ‘patient’ and ‘subject’ are both used to describe the individual 
who enrolls in this study. 
1.1 
Study Overview 
This is a Phase 2a, open-label, randomized, multi-center, multi-region study of subcutaneously 
(SC) administered ISIS 702843 in patients with non-transfusion dependent β-Thalassemia 
Intermedia.   
The study will comprise 3 cohorts: Cohorts A, B, and C. Under the original Protocol and 
Protocol Amendment 1, the study was to enroll approximately 36 patients, randomized to 
Cohorts A (ISIS 702843 30 mg), B (ISIS 702843 50 mg), and C (ISIS 702843 80 mg) in a ratio 
of 1:1:1.  
Upon the approval of Protocol Amendment 2, the study design was updated, and the patients 
were randomized in parallel to Cohort B or Cohort C, with no new patients randomized to 
Cohort A.  In addition, the dose level for Cohorts A and B became the same at 120 mg ISIS 
702843 per dose.  The dose level for Cohort C became 120 mg ISIS 702843 per dose for three 
consecutive doses, followed by 160 mg ISIS 702843 per dose, if dose escalation was allowed 
based on a demonstration of adequate safety.  The eligible patients were stratified based on 
Screening mean Hb status of low (≤ 8.0 g/dL) or high (> 8.0 g/dL).   
There were 12 patients in Cohorts A and B combined, and 17 patients in Cohort C.  The study 
consisted of Screening, Treatment, and Post-Treatment periods.  The overall length of a subject’s 
participation was to be approximately 29 months (up to 2 months for the Screening Period, a 
24-month Treatment Period, and a 3-month Post-Treatment Period). 
Each patient was to be treated for up to 2 years, receiving up to 27 doses of ISIS 702843, with a 
planned 28-day interval between each dose.  
 
Unless the allowances in the circumstance of a public 
health emergency apply (Section 3.8 in the  protocol), all Study Drug injections will be SC 
administered at the clinic through Day 365 (Week 53) and can be SC administered away from 
the clinic after that visit. 

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The study design and treatment schema are depicted as follows: 
 
1.2 
Objectives 
1.2.1 Primary Objective 
Evaluate the efficacy of antisense inhibitor of TMPRSS6 (ISIS 702843) by demonstrating an 
improvement in hemoglobin (Hb) concentration at Week 27 of treatment. 
 
TREATMENT PERIOD 
• Stratify eligible patients based on Screening Mean Hb 
for Eligibility, low (≤ 8.0 g/dL) and high (> 8.0 g/dL) 
• Randomize in parallel to Cohort B or C.  (No patients 
will be randomized to Cohort A after Amendment 2 
approval.) 
• Every 4 weeks administration of ISIS 702843, 
Weeks 1-105 
• Self-administration is allowed after Week 53 – earlier if 
Section 3.8 applies – and training 
• Modify dose and/or dose frequency, as needed, based 
on safety monitoring rules 
• Safety & efficacy measurements obtained at regular 
intervals 
• First interim analysis based on evaluations through 
Day 183 (Week 27) 
• Second interim analysis based on evaluations through 
Day 365 (Week 53) 
EARLY TERMINATION FROM 
TREATMENT (ETFT) 
• Patients who discontinue ISIS 702843 
treatment and agree to remain in the 
study will attend the following clinic 
visits: ETFT, PTP Visit 1, PTP Visit 2, 
and PTP Last Visit. If patient is unable 
or unwilling to participate in all of these 
visits, the PI should determine the 
follow-up procedures the patient would 
agree to complete. 
• Every effort should be made to complete 
the ETFT study procedures and 
observations at the time of withdrawal 
SCREENING 
Weeks -9 to -1 
POST-TREATMENT PERIOD (PTP) 
• Three (3) assessments, spanning 13 weeks after last 
dose 
END-OF-STUDY PROCEDURES 
•
PTP Last Visit or ETFT 

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1.2.2 Secondary Objectives 
• Evaluate the efficacy of ISIS 702843 by demonstrating an improvement (increase) in 
Hb concentration at Week 53 of treatment. 
• Evaluate the efficacy of ISIS 702843 by demonstrating an improvement (decrease) in 
liver iron concentration (LIC) at Week 53 of treatment. 
1.2.3 Exploratory Objectives 
• Evaluate the impact of ISIS 702843 on Ineffective Erythropoiesis (IE): 
Erythroferrone (ERFE); soluble transferrin receptor 1 (sTfR1); reticulocyte count; 
reticulocyte Hb content (CHr); erythropoietin (EPO); growth differentiation factor 15 
(GDF15); bone marrow iron concentration. 
• Evaluate the impact of ISIS 702843 on measures of iron overload: 
LIC; serum transferrin saturation (TSAT); serum ferritin. 
• Evaluate the efficacy of ISIS 702843 by demonstrating an increase in serum hepcidin 
concentration. 
• Evaluate the efficacy of ISIS 702843 by demonstrating improvement in anemia 
parameters: 
Hb; RBC count; hematocrit; MCV; mean corpuscular hemoglobin (MCH); mean 
corpuscular hemoglobin concentration (MCHC) 
• Evaluate the impact of ISIS 702843 on hemolysis: 
bilirubin (indirect); lactate dehydrogenase (LDH) 
• Evaluate the impact of ISIS 702843 on coagulation profile: 
Prothrombin time (PT); international normalized ratio (INR); activated partial 
thromboplastin time (aPTT) 
• Evaluate the impact of ISIS 702843 on disease severity: 
Number of transfusions; chelator usage 
1.2.4 Safety Objectives 
• Evaluate the safety and tolerability of multiple doses of ISIS 702843 in patients with 
β-Thalassemia Intermedia. 
• Evaluate the impact of multiple doses of ISIS 702843 on the emergence and/or 
progression of recognized complications of β-Thalassemia Intermedia. 

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1.2.5 Pharmacokinetic objectives 
Evaluate pharmacokinetic (PK) exposure over time and potential PK / pharmacodynamic (PD) 
correlation on relevant biomarkers and efficacy outcome measures. 
1.3 
Endpoints 
1.3.1 Primary Endpoint 
Proportion of patients who have a ≥ 1.0 g/dL increase from Baseline in Hb, comparing the 
3 cohorts at Week 27 of treatment. 
1.3.2 Secondary Endpoints 
• Proportion of patients who have a ≥ 1.5 g/dL increase from Baseline in Hb, 
comparing the 3 cohorts at Week 53 of treatment. 
• Proportion of patients who have a ≥ 1.0 mg Fe/g dry weight decrease from Baseline 
in LIC, comparing the 3 cohorts at Week 53 of treatment. 
1.3.3 Exploratory Endpoints 
• Change from baseline of IE assessment, including plasma erythroferrone 
concentration, plasma sTfR1 concentration, reticulocyte count, reticulocyte Hb 
content (CHr), plasma EPO concentration, plasma GDF15 concentration, and bone 
marrow iron concentration, comparing the 3 cohorts over time. 
• Change from baseline of iron overload assessment, including:  LIC, TSAT, serum 
ferritin, chelator usage, and hepcidin, comparing the 3 cohorts over time. 
• Change from baseline of anemia assessments including: Hb, RBC count, hematocrit, 
mean corpuscular volume (MCV), mean corpuscular Hb (MCH) amount, and 
corpuscular Hb concentration (MCHC), comparing the 3 cohorts over time.  
• Change from baseline of hemolysis assessment, including plasma bilirubin (indirect), 
and plasma LDH, comparing the 3 cohorts over time. 
• Change from baseline of hypercoagulability profile, including PT, INR, and aPPT, 
comparing the 3 cohorts over time.  
• Change from baseline on disease severity, including change in the number of 
transfusions and chelator usage, comparing the 3 cohorts over time.  

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1.3.4 Safety Endpoints 
• Adverse events (AEs), vital signs, physical examination findings, clinical laboratory 
tests (serum chemistry, hematology, urinalysis, coagulation panel, thyroid panel), 
electrocardiogram (ECG). 
• Measures of extramedullary hematopoiesis, liver function, splenomegaly, 
osteoporosis, diabetes, and pulmonary hypertension (PHT). 
1.3.5 Pharmacokinetic Endpoints 
A PK profile (including pre-dose sampling) over a 6-hour period will be collected at Day 1 
(Week 1).  Two (2) samples, pre-dose and 3-hour, will be evaluated at Day 197 (Week 29).  
Trough levels will be evaluated just prior to each dose through Day 169 (Week 25), as well as on 
a more limited basis throughout the rest of the Treatment Period.  One (1) sample will be 
evaluated on Day 183 (Week 27); there is no dose at this visit. In the Post-Treatment Period, 
1 sample per each of the 3 planned visits will be evaluated, as available. 
2 
PROCEDURES 
2.1 
General Overview of Procedures 
Ionis Pharmaceuticals, Inc. (or designee) will review all study data including source documents, 
case report forms, and laboratory reports.  The study site will enter subject source data into the 
case report form.  Some laboratory data will be transferred electronically from PPD 
Development (plasma PK) to Ionis Pharmaceuticals, Inc.  Additional lab data will be transferred 
from Medpace Reference Laboratories (MRL) as the central lab, as well as from other specialty 
laboratories.  
2.2 
Randomization & Treatment Allocation 
Patients were randomized after all screening assessments were completed and after the 
Investigator verified that they are eligible per criteria in protocol Sections 5.1 and 5.2.  No 
subject began treatment prior to randomization and assignment of a unique subject identification 
number.   
Eligible patients were stratified based on screening Mean Hb (≤ 8.0 g/dL or > 8.0 g/dL) and then 
patients were randomized.  Under the original Protocol and Protocol Amendment 1, 
approximately 36 patients were to be randomized into 3 treatment cohorts (ISIS 702843 30 mg, 
50 mg, or 80 mg) in a ratio of 1:1:1.  However, upon approval of Protocol Amendment 2, 
patients were randomized in parallel to Cohort B (120 mg ISIS 702843 per dose) or Cohort C 
(120 mg ISIS 702843 per dose for 3 consecutive doses, followed by 160 mg ISIS 702843 per 
dose, if dose escalation is allowed based on a demonstration of adequate safety), following a 
prespecified randomization schema.  No patients were randomized to Cohort A after Amendment 

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2 approval.  A summary of treatment cohort and planned dose is presented in Table 1, Section 
8.1 in the protocol. 
Eligible patients must have a clinical diagnosis of β-Thalassemia Intermedia with genotypic 
confirmation of β-globin gene mutation and must be non-transfusion dependent in order to 
participate in the study (see protocol Section 5.1 Inclusion Criteria).  The Sponsor or designee 
prepared the randomization list and utilized an automated IRT (Interactive Response 
Technology) system. 
2.3 
Conduct 
The study was conducted in accordance with current Good Clinical Practice (GCP) and 
International Conference on Harmonization (ICH) guidelines, the Food and Drug Agency (FDA) 
Code of Federal Regulations, and all other local regulatory requirements. 
2.4 
Data Monitoring 
2.4.1 Safety Data Monitoring 
Ionis Pharmaceuticals, Inc. (or designee) is responsible for processing all reported adverse events 
(AEs).  All serious adverse events (SAEs), reported to Ionis Pharmaceuticals, Inc. (or designee), 
are reviewed according to standard operating procedures.  The medical monitor will review all 
AEs and SAEs on an ongoing basis throughout the study.  Ionis Pharmaceuticals, Inc. (or 
designee) will prepare and submit safety reports to the health authorities worldwide in 
accordance with local requirements.  If it becomes necessary to communicate new safety 
information, Ionis Pharmaceuticals, Inc. (or designee) will also prepare a safety notification letter 
and transmit it to all applicable study sites. 
2.4.2 Data Monitoring Board 
An internal safety committee was planned, as described in Section 3.6 of the protocol.  However, 
this committee did not meet because the Sponsor Medical Monitor prepared medical monitoring 
reports at a frequency of approximately every 1 to 2 months, no concerning safety trends were 
identified, and the study was terminated early by the Sponsor due to a lack of efficacy.   
2.5 
Data Management 
An electronic case report form (eCRF) utilizing an Electronic Data Capture (EDC) application 
was used for this Study. 
2.5.1 Case Report Form Data 
Clario (or designee) is responsible for creating the Electronic Data Capture (EDC) data entry 
screens, database and edit checks using definitions developed by Ionis Pharmaceuticals, Inc. 
Ionis Pharmaceuticals, Inc. is responsible for the review, data management querying and locking 
of the database. 

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Data are single-entered into the EDC system by the investigator site staff.  Programmed edit 
checks (computer logic that checks the validity of the data entered and also prompts for missing 
data that is expected to be entered) are run and automatic queries are generated.  Ionis 
Pharmaceuticals, Inc. reviews all data for accuracy and validity and generates additional queries 
in the EDC system when necessary.  The data is corrected or an explanation concerning the 
query is provided in the EDC system.  After all data are entered, source data verified, reviewed 
and queried, the database is closed.  The data is then reviewed by Ionis Pharmaceuticals, Inc. and 
additional queries may be generated.  After all queries are resolved, the database is locked. 
2.5.2 Laboratory Data 
Ionis Pharmaceuticals, Inc. is responsible for the format of the laboratory electronic data 
transfers, transfer schedule and review of the clinical laboratory data.  For the central lab, the 
data is not stored in the EDC system.  Investigator sites have access to the data via lab reports 
sent directly from the laboratory and online using the MRL ClinTrak® database.  In addition, 
Investigators may, at their discretion, test specific laboratory parameters at their local laboratory 
for safety assessments prior to dosing.  In these instances, the local laboratory results will be 
recorded by the site into the EDC system.  The final lab data will be stored as SAS data sets. 
For specialty labs such as Blueprint Genetics, BioPharma Diagnostics (Mayo), Medpace Core 
Laboratories, QPS Holdings, L.L.C., Radboud, Resonance Health, Ionis Research Lab, and 
Versiti Blood Center of Wisconsin, data will be transferred directly to Ionis per each vendor’s 
Data Transfer Agreement, if applicable.   
2.5.3 Pharmacokinetics Data 
Ionis Pharmaceuticals, Inc. is responsible for the management and review of the plasma drug 
concentration data from PPD®.  This process involves reviewing the subject and visit identifiers 
(i.e., subject demographics) with the clinical data collected in the EDC system.  The PK data will 
be stored as CSV and/or EXCEL files.  Final data, which has been approved by Quality 
Assurance, will be stored in the Sponsor’s document management system.  
2.5.4 Immunogenicity (IM) Analysis 
Ionis Pharmaceuticals, Inc. is responsible for the management and review of the immunogenicity 
sample data from Charles River Laboratories-Montreal.  This process involves reviewing the 
subject and visit identifiers (i.e., subject demographics) with the clinical data collected in the 
EDC system.  The ADA data will be stored as CSV and/or EXCEL files.  Final data, which has 
been approved by Quality Assurance, will be stored in the Sponsor’s document management 
system. 

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3 
ANALYTICAL PLAN 
3.1 
Statistical Design Summary 
The study enrolled 29 patients overall, with 12 patients in Cohorts A and B combined, and 
17 patients in Cohort C . The eligible patients were stratified based on a screening mean Hb level 
status [low (≤ 8.0 g/dL) or high (> 8.0 g/dL)].  There is no statistical rationale for the selected 
sample size. Each patient was to be treated for up to 2 years.  The outcomes are descriptive.  
Two (2) interim analyses were planned. Refer to Section 3.3.4 for the timing and the objectives 
of the interim analyses.  However, neither interim analysis was formally performed (i.e., with a 
database lock) because it became clear from safety monitoring that blood hemoglobin was not 
increased before the planned analyses were to be conducted.  In lieu of a formal first interim 
analysis, an analysis of the available data was conducted, and the protocol was amended to allow 
higher doses to be tested.  In lieu of a formal second interim analysis, the available data were 
analyzed, and after careful consideration the decision was made to terminate the study early. 
3.2 
General Overview of Analyses 
3.2.1 Statistical Methods 
Descriptive summary statistics including number of patients, mean, median, standard deviation, 
standard error of mean, 25th percentile, 75th percentile, minimum, and maximum for continuous 
variables, and counts and percentages for categorical variables will be provided to summarize 
most data.  Additional subject listings included case report form (CRF) data and derived 
outcomes from the data may be presented.   
Unless otherwise specified, the study outcomes will be summarized by treatment cohort 
(Cohort A, Cohort B, Cohort C, Cohorts A and B combined, and total).  
For the categorical outcomes, the data will be analyzed by using one-sample Exact test to 
evaluate whether the estimate proportions are deviated from zero.  For the continuous outcomes, 
the data will be analyzed using one-sample t-test to evaluate if the changes from baseline are 
significantly different than zero.  The normality assumption for one-sample t-test model will be 
assessed by the Shapiro-Wilk test.  In the case of data departs substantially from normality, the 
nonparametric Wilcoxon signed rank test will be applied instead.  
All statistical tests will be conducted using 2-sided tests with 5% Type I error rate unless 
otherwise stated.  Where appropriate, p-values will also be provided for statistical tests.  
For Hb, the collected Hb values within 6 weeks after the time of receiving an RBC transfusion 
will be considered as missing in the efficacy analyses.  Mean, mean of absolute change from 
baseline, and mean percent change from baseline over time by treatment cohort will be plotted 

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for the selected analytes in the efficacy analyses.  Given the limited size of the cohort, median of 
the summary over time by treatment cohort plot may also be provided.  
Baseline Definition 
The baseline for Hb and other hematology parameters is defined as the average of Screening 
period and Day 1 pre-dose measurement.  Each measurement used for the baseline calculation 
must be taken at least 6 weeks away after the most recent transfusion.  Baseline must be based on 
at least two measurements.   
The baseline for all other assessments is defined as the last non-missing measurement prior to the 
first dose of study drug. For ECG, the baseline is defined as the average of the last non-missing 
triplicate prior to the first dose of study drug. 
Analytical Visits 
In general, all post-baseline data will be summarized using the visit labels provided in the data.  
Multiple results with the same visit label will be averaged for the continuous variables, and the 
worst result will be used for the categorical variables.  Results with visit labels as “Unscheduled” 
will not be included in the by-visit summary tables and figures except for determining baseline 
and the incidence of abnormality lab summary including AST, ALT, and platelet number 
specified in Section 3.7.3 but will be presented in data listings.  Other situations, such as required 
additional confirmation, will be described separately in the related endpoint analysis approach. 
Disposition of Subjects 
The number of patients screened, the number of patients screen failures, the number and 
percentage of patients enrolled, the number and percentage of patients completed the study 
treatment, the number and percentage of patients who discontinued from treatment early and 
reason, the number and percentage of patients completed post-treatment follow-up, and who 
discontinued from post-treatment follow-up and reason will be summarized.  A by-patient listing 
will also be provided. 
Additional summaries will be provided to summarize the number of patients with screen failure, 
and treatment/post-treatment follow-up termination incidences related to the COVID-19 public 
health emergency.  A listing will also be provided to present the incidences above.  Please refer 
to Section COVID-19 Related Impact for more information about this listing. 
Demographic and Baseline Characteristics 
Demographic, stratification factors and Baseline characteristics (e.g., age, gender, ethnicity, race, 
weight, height, BMI, splenectomy status, screening Hb, prior packaged RBC transfusion rate 
(unit/yr), and on chelation medication at Day 1) will be summarized using descriptive statistics 
by treatment cohort.  Other disease characteristics related assessments, such as ferritin, TSAT, 
and LIC, will be summarized in the summary tables separately. 

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As for the information of race, if multiple races are selected in the database, then ‘Multiple Race’ 
is used in the summary table and the data point will only be counted once in the category of 
‘Multiple Race’.  The listing will display the specific race information.  
BMI will be computed using the formula: BMI = (weight in kilograms) / [screening height in 
cm / 100]2 
All protocol deviations will be listed and be summarized.  An additional summary table by 
deviation type and classification will be provided to illustrate the protocol deviations that are 
related to the COVID-19 public health emergency.  
The protocol deviations related to the COVID-19 public health emergency will be listed 
separately.  Please refer to Section COVID-19 Related Impact for more information about this 
listing. 
COVID-19 Related Impact 
A listing of all patients affected by the COVID-19 public health emergency related study 
disruption will be provided.  The listing will include the information in the following category 
with corresponding results and/or comments, if available. 
• Screen failure 
• Treatment termination/ Follow-up termination 
• Protocol deviation 
• Local lab data 
3.2.2 Subject Population Analyzed 
The following analysis populations are defined for this study: 
• Safety Set: All randomized patients who received at least 1 dose of ISIS 702843. 
• PK Set: All randomized patients who received at least 1 dose of ISIS 702843 and have at 
least 1 evaluable PK sample.   
• Full Analysis Set (FAS): All randomized patients who received at least 1 dose of 
ISIS 702843 and who have at least 1 post-baseline Hb assessment after Day 1. 
ln addition to the above analysis sets, it is recognized that some data displays will be provided 
for "All Screened", "Screening Failures", and "All Randomized" subjects but no data analysis is 
planned to be executed in these populations.  

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3.3 
Primary Analysis 
3.3.1 Primary Endpoint Definition 
The proportion of patients who have a ≥ 1.0 g/dL increase from Baseline in Hb at Week 27 of 
treatment in the FAS.   
3.3.2 Analysis of Primary Endpoint 
The primary analysis will be the proportion of patients achieving ≥ 1.0 g/dL increase from 
baseline at Day 183 (Week 27) in Hb summarized by treatment cohort in the FAS.  The data will 
be analyzed using one-sample Exact test as described in Section 3.2.1.  Ninety-five (95%) exact 
confidence interval of the response rate will also be provided.   
The value to use for Week 27 result is the mean of the 2 Hb measurements intended to be taken 
at Day 169 (Week 25) and Day 183 (Week 27); if one of these measurements is missing, then the 
other measurement will be used for Week 27 result.  For a Hb measurement to be usable for 
Week 27 result, the sampling must occur at least 6 weeks after the most recent transfusion for 
that patient.  The end time of the transfusion will be derived as 4 hours from the start time. 
Based on preliminary analysis (see Section 3.3.4), only comparison between week 27 and 
baseline within each cohort will be provided.   
3.3.3 Sample Size Consideration 
The sample size was based on prior experience with second-generation ASOs to ensure that the 
safety, tolerability, efficacy, and PK of ISIS 702843 will be adequately assessed while 
minimizing unnecessary subject exposure.  The maximum enrollment of patients was expected to 
be 30 (or until enrollment is closed by the Sponsor).  The Sponsor closed enrollment to 
Cohorts A and B before enrollment to Cohort C because it was considered sufficient to have 
approximately 12 patients in Cohorts A and B combined. 
For a set of 12 enrolled patients, the chance to observe no responder in primary endpoint is 
around 28% if the true response rate is 10%, but the chance to observe no responder decreases to 
around 1% if the true response rate becomes 30%.   
3.3.4 Planned Interim Analyses 
Two (2) interim analyses (IAs) were planned: 
• When at least 20 patients had completed Day 183 (Week 27) assessments.  The main 
purpose of this IA was to evaluate ISIS 702843 efficacy effect on Hb, other hematology 
measures, and Iron panel measures.  The information was to be used to support decisions 
related to the potential for dose adjustments applicable to an entire cohort.   

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• When at least 16 patients had completed Day 365 (Week 53) assessments.  The main 
purpose of this IA was to evaluate ISIS 702843 efficacy effect on LIC and further on the 
measures associated with the first interim analysis.   
However, neither IA was formally performed (i.e., with a database lock) because it became clear 
from safety monitoring that blood hemoglobin was not increased before the planned analyses 
were to be conducted.  In lieu of a formal first interim analysis, the available data were analyzed, 
and the protocol was amended to allow higher doses to be tested. In lieu of a formal second 
interim analysis, the available data were analyzed, and the decision was made to terminate the 
study.  
3.3.5 Incomplete or Missing Data 
Missing values will not be imputed.  Patients with missing data for a scheduled assessment time 
point were excluded from the summary for that time point. 
3.4 
Secondary Analyses 
3.4.1 Secondary Endpoint Definitions 
• Proportion of patients who have a ≥ 1.5 g/dL increase from Baseline in Hb at Week 53 of 
treatment. 
• Proportion of patients who have a ≥ 1.0 mg Fe/g dry weight decrease from Baseline in 
LIC at Week 53 of treatment. 
3.4.2 Analysis of Secondary Endpoints 
The secondary efficacy analyses will be performed in a similar way to the primary efficacy 
analysis and conducted using the FAS.  The proportion of patients achieving ≥ 1.5 g/dL increase 
from baseline at Day 365 (Week 53) in Hb summarized by treatment cohort in the FAS.  For a 
Hb measurement to be usable for the determination of the value to use for Week 53 of treatment, 
the sampling must occur at least 6 weeks after the most recent transfusion for that patient.  The 
value to use for Week 53 result is the mean of the 2 Hb measurements intended to be taken at 
Day 309 (Week 45) and Day 365 (Week 53); if one of these measurements is missing, then the 
other measurement will be used for Week 53 result. For a Hb measurement to be usable for 
Week 53 result, the sampling must occur at least 6 weeks after the most recent transfusion for 
that patient. 
The proportion of patients who have a ≥ 1.0 mg Fe/g dry weight decrease from Baseline in LIC 
at Week 53 will be summarized by treatment cohort in FAS.  The Week 53 value is the LIC 
measurement intended to be taken at Day 365 (Week 53). 
Based on preliminary analysis (see Section 3.3.4), only comparison between Week 53 and 
baseline within each cohort will be provided.  

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3.5 
Exploratory Analyses 
The exploratory endpoints listed in Section 1.3.3 will be summarized by treatment cohort in the 
FAS.  The analyses based on the outcome characteristics (continuous or categorical) will be 
summarized by scheduled visits.  For continuous outcomes, mean, mean of absolute change from 
baseline, and mean percent change from baseline over time will be summarized by scheduled 
visits, and treatment cohort.   
The number and percentage of patients who achieved additional response criteria for key iron 
parameters will be tabulated also.  For Hb, the response criteria will include increase by 
≥ 1.0 g/dL from baseline; increase by ≥ 1.5 g/dL from baseline.  For LIC, the response criteria 
will include reduction by 1.0 mg Fe/g dry weight from baseline.  For TSAT, the response criteria 
will include reduction by ≥ 10% from baseline; reduction by ≥ 20% from baseline; reduction by 
≥ 30% from baseline; reduction by ≥ 50% from baseline.  Percentages are calculated based on 
the number of patients with available samples at certain visit.     
Individual plots with several selected analytes over time may be provided.  
Based on preliminary analysis (see Section 3.3.4), only comparison between week 53 and 
baseline for Hepcidin within each cohort will be provided.  
The following exploratory endpoints as described in the protocol will not be analyzed since the 
Sponsor terminated the study due to a lack of efficacy.  The study team has decided not to 
present this part of analyses in the abbreviated CSR because primary and secondary endpoints 
were not met: 
• Change from baseline of erythroblast count 
• Change from baseline of spleen iron concentration, and non-transferrin bound iron 
(NTBI) 
• Change from baseline of plasma haptoglobin, plasma protoporphyrin IX, and blood 
smears 
• Change from baseline of antithrombin III, Protein S, and Protein C 
• Change from baseline on quality of life measures, including change from baseline in 
NTDT-PRO©, SF-36, PGIC, ISGA, and FACIT-Fatigue 
• 
Change from baseline on functional status of patient using 6MWT instrument 
3.6 
Pharmacokinetic (PK) and Immunogenicity (IM) Analysis 
Pharmacokinetic (PK) analysis will be conducted in the PK Population.  The plasma 
pharmacokinetics of ISIS 702843 (as total full-length antisense oligonucleotide (ASO) or 

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ISIS 702843-equivalent, ISIS 702843-eq., including fully conjugated, partially conjugated, and 
unconjugated ISIS 702843) will be assessed following SC dose administration.   
3.6.1 Plasma Concentration Data of Total Full-Length Oligonucleotides 
Plasma concentrations of ISIS 702843 (ISIS 702843eq.), along with the scheduled (nominal) and 
actual sample times (i.e., time from SC dosing) will be listed (when applicable) for each patient, 
by dose cohort, nominal and actual dose, study day, scheduled and actual time point, and dose 
number with respect to nominal dose assigned by relevant protocol amendment.  In addition, 
percent differences between scheduled and actual sampling times will be listed for all patients, as 
well as percent differences between actual administered dose and nominal dose.  
Plasma concentrations below the lower limit of quantification (LLOQ) will be indicated by 
“BLQ”.  For the purpose of calculating typical descriptive statistics (n, mean, SD, %CV, 
geometric mean, geometric %CV, median, minimum, and maximum) for plasma concentrations, 
all BLQ values will be set to zero.  Mean plasma concentrations that are BLQ will be presented 
as “BLQ”, and the SD and %CV, geometric mean and geometric % CV will be reported as not 
applicable.  Summary statistics of the ISIS 702843 plasma concentrations will be tabulated by 
nominal dose as assigned per relevant protocol amendment, dose number with respect to nominal 
dose assigned at randomization and subsequently per relevant protocol amendment, nominal 
study day, and scheduled time point.  At the discretion of the pharmacokineticist and/or 
biostatistician, samples may be excluded from descriptive statistics if there are large deviations 
between scheduled and actual sampling times, or large deviations between actual dose and 
nominal dose. 
ISIS 702843eq. plasma concentration versus time (actual) profiles for each patient that received 
ISIS 702843, as well as the mean (± SD or SE) plasma concentrations versus time (scheduled) 
profiles, will be presented graphically on linear and semilogarithmic scales.  At the discretion of 
the pharmacokineticist and/or biostatistician, samples may be excluded from the mean plots if 
there are large deviations between scheduled and actual sampling times. 
3.6.2 Plasma Pharmacokinetic Parameters 
The plasma PK of ISIS 702843 (as total full length ASO) will be assessed following the first 
SC dose, as data allows.  Non-compartmental PK analysis of ISIS 702843 (total full-length ASO) 
will be carried out on each individual subject data set using Phoenix WinNonlin version 8.0 or 
higher (Pharsight Corporation, Mountain View, CA).  For calculation of PK parameters, all BLQ 
values will be set to zero.  The plasma PK parameters for ISIS 702843eq. will be calculated 
based on actual sampling times.  The plasma PK parameters to be calculated or determined 
(when applicable) are listed in Table 2.  Other plasma PK parameters, as appropriate, may be 
determined or calculated at the discretion of the pharmacokineticist. 

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Table 2 
Plasma Pharmacokinetic Parameters to be Calculated or Determined 
Parameter 
Definition/Method 
Study 
Day 1 
Cmax 
Maximum observed concentration 
X 
Tmax 
Observed time at which Cmax occurs 
X 
Tlast 
Time of last measurable (positive) concentration 
X 
AUC0-t 
Partial AUC:  Area under the concentration-time curve from time zero to time t 
(e.g., 6 hr, as applicable), calculated using linear-up log-down method 
X 
CL0-t/F 
Partial clearance (e.g., 6 hr) divided by F (fraction of the dose absorbed) 
determined by Dose/AUC0-t 
X 
t1/2λz 
For all evaluable patients who have sufficient post-treatment samples collected, 
apparent terminal elimination half-life will be calculated from the equation, 
t1/2λz = 0.693/λz, where λz is the rate constant associated with the apparent 
terminal elimination phase.  A minimum of three data points in the elimination 
phase will be used to define λz, a span of at least 1.5, and the correlation of 
determination values (r2 adjusted) must be at or greater than 0.8 for the estimate 
to be accepted.  This parameter will only be calculated following the final dose 
on Day 729 for all evaluable patients receiving active study drug. 
X 
Note:  X designates parameters to be calculated or determined assuming sufficient data 
 
Plasma pharmacokinetic parameters will be summarized using descriptive statistics (n, mean, 
SD, %CV, geometric mean, geometric %CV, median, minimum, and maximum) by nominal 
dose and study day.  Summary may also include dose number with respect to nominal dose 
assigned at randomization and subsequently per relevant protocol amendment. 
3.6.3 Pharmacokinetic/Pharmacodynamic Exposure-Response Analysis 
Exposure-response correlations may be explored graphically between plasma exposure 
(i.e., AUC, Cmax, Ctrough, as appropriate), and selected PD measures (e.g., hemoglobin), and/or 
other relevant biomarkers (such as hepcidin, TSAT, serum iron, etc.).  
Population PK and PK/PD analysis may be performed using the PK and PD data from this Study, 
and/or combined with other ISIS 702843 clinical PK/PD data from any previous and future 
studies in the development timeline. 
3.6.4 IM Analysis 
Anti-drug antibody (ADA) analyses will be conducted in the ‘Safety Set’.  Samples collected for 
ADA assessment at selected time points will be analyzed for anti-ISIS 702843 antibodies 
(i.e., anti-drug antibodies; ADA).  

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3.6.4.1 Sample Level ADA data 
An evaluable sample will be designated ‘IM positive’ based on both positive screening and 
confirmation assay results (i.e., confirmed positive result), and otherwise will be deemed ‘IM 
negative’.  Sample IM results (screen positive/negative, confirmed positive/negative or 
unevaluable, and when applicable, titer of anti-ISIS 702843 antibodies) before, during, and after 
treatment with ISIS 702843 (sample ADA status) will be listed for each subject by treatment, 
dose (nominal and actual), dose number with respect to nominal dose assigned at randomization 
and subsequently per relevant protocol amendment, as well as study day of collection (nominal 
and actual).   
The sample ADA incidence (number) and incidence rate (percent) at each evaluated study time 
point will be determined and appropriately summarized by treatment and dose as the total 
number of and percentage of evaluated subjects with sample ADA negative, positive, and 
unknown status.  Furthermore, titer over time will be also appropriately summarized (using 
descriptive statistics) as median, quartiles (25% and 75%), and range by treatment and dose.  
Summary may also include dose number with respect to nominal dose assigned at randomization 
and subsequently per relevant protocol amendment. 
3.6.4.2  Subject Level ADA data 
Subject ADA status overall (ADASTAT) will be defined as ‘Positive’ if they have at least 
1 confirmed positive sample result at any time during the treatment or post-treatment evaluation 
periods; ‘Negative’ if all evaluated ADA sample results during the treatment and post-treatment 
evaluation periods are ADA negative and they have at least one evaluable ADA result collected 
post study drug treatment.  Otherwise, a study patient will be assigned ‘Unknown’ ADA status.  
Furthermore, subjects with positive overall ADA status will be further classified into different 
ADA types based on their baseline ADA status and change in ADA titer post treatment as 
described below (Shankar et al. 2014): 
• Treatment-Emergent ADA: sum of treatment-induced ADA and treatment-boosted 
ADA as described below: 
o Treatment-Induced ADA: ADA developed de novo (seroconversion) following 
biologic drug administration (i.e., formation of ADA any time after the initial 
drug administration in a subject without pre-existing ADA, i.e., baseline negative 
ADA) 
o Treatment-Boosted ADA: pre-existing ADA that were boosted to a higher level 
following biologic drug administration (i.e., any time after the initial drug 
administration the ADA titer is greater than the baseline titer by a factor of 8-fold 
or more) 

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• Treatment-Unaffected ADA: pre-existing ADA that were not affected (boosted) 
following biologic drug administration (i.e., any time after the initial drug 
administration the ADA titer is 4-fold or less) 
• ADA type would be not applicable (NA) if the subject overall ADA status is 
negative. 
Other subject level IM parameters to be calculated/defined may include but are not limited to: 
• Subject ADA Status at Baseline (ADASTATB): "Positive" if the subject has Week 1 
Day 1 pre-dose sample (baseline) tested as confirmed positive; "Negative" if the 
subject has Week 1 Day 1 pre-dose sample (baseline) tested as confirmed negative; 
"Unknown" if the subject has Week 1 Day 1 pre-dose sample (baseline) that is 
unevaluable. 
• Onset of ADA (TFSTADA): i.e., the first day ADA positive sample observed, will be 
calculated by: the date first sample has “positive” IM status - first dose date +1.  This 
parameter will be calculated for subjects with positive ADA status overall and 
subjects with treatment-induced ADA, respectively.  
• Last Positive ADA Study Day (TLSTADA):  defined as the last positive ADA sample 
observed from the start of study drug treatment and will be calculated by:  the date of 
last sample “positive” IM status - first dose date +1. 
• Last IM Sampling Study Day (TLSTSAMP): defined as the last ADA sample 
collected from the start of study drug treatment and will be calculated by:  the date of 
last sample collected - first dose date +1. 
• Peak titer (PEAKTIT):  the highest titer observed for the subject  
• Time to peak titer (TPEAKTIT):  the time to reach peak titer will be calculated 
by:  the date of first peak titer observed- first dose date +1 
• Total number of ADA Positive Samples (NOPOSAMP):  the total number of ADA 
samples being confirmed positive for the subject  
• Total number of ADA Samples evaluated (NOADASAMT): the total number of 
ADA samples being collected and analyzed successfully with reportable results for 
the subject 
•  Percentage of Positive Samples (PCPOSAMP):  the percentage of ADA samples 
being confirmed positive for the subject and will be calculated by: 
PCPOSAMP (%) =  100 × NOPOSAMP
NOADASAMT 

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Lastly, subjects with positive ADA status may further be classified as having transient or 
persistent ADA response, if there are a sufficient number of subjects with transient ADA status. 
Transient and persistent ADA definitions are defined below and based on Shankar 2014 
(Shankar et al. 2014): 
Transient ADA response:  
• Treatment-induced ADA detected only at one sampling time point during the 
treatment or follow-up observation period (excluding the last sampling time point, 
which will be considered persistent unless shown to be undetectable at a later time) or 
• Treatment-induced ADA detected at two or more sampling time points during the 
treatment (including follow-up period if any), where the ﬁrst and last ADA-positive 
samples (irrespective of any negative samples in between) are separated by a period 
less than 16 weeks, and the subject’s last sampling time point is ADA-negative. 
Persistent ADA response: 
• Treatment-induced ADA detected at two or more sampling time points during the 
treatment (including follow-up period if any), where the ﬁrst and last ADA-positive 
samples (irrespective of any negative samples in between) are separated by a period 
of 16 weeks or longer or 
• Treatment-induced ADA detected only at the last sampling time point of the study 
treatment period or at a sampling time point with less than 16 weeks before an 
ADA-negative last sample. 
The subject level ADA prevalence, incidence, and positive ADA response being transient or 
persistent (if applicable) will be calculated as the number and the proportion (percent) of the 
study population during the study period by treatment and dose.  Subject level IM parameters (as 
described above) will be listed by treatment and dose for all evaluable subjects, and also 
appropriately summarized (using descriptive statistics) as median, quartiles (25% and 75%) and 
range, by treatment and dose.  Additionally, Subject level IM parameters will be summarized for 
subjects with Treatment-Induced ADA only (i.e., excluding subjects with pre-existing ADA).  
Summary may also include dose number with respect to nominal dose assigned at randomization 
and subsequently per relevant protocol amendment. 
3.6.4.3 Evaluation of IM Impact on PK, PD, Efficacy and Safety 
The impact of IM on PK, PD and safety may be evaluated by stratifying plasma PK parameters, 
plasma trough and post-treatment ISIS 702843 concentrations and PD biomarker levels, selected 
clinical efficacy endpoints and safety measures by subject ADA status and titer quartiles, 
summarized using typical descriptive statistics, and presented graphically and/or in tables.  The 
impact of IM may also be evaluated on selected clinical efficacy end points and safety measures.  

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Additionally, within subject comparisons on plasma Cmax and AUC may be conducted in 
patients from the PK subgroup and presented graphically by subject IM status and treatment if 
deemed appropriate (Wang et al. 2016). 
Lastly, other stratifications (e.g., based on antibody titer, onset of ADA, etc.) of selected PK, 
efficacy, and safety assessments may also be performed if deemed warranted at the discretion of 
the pharmacokineticist, medical monitor, and/or biostatistician. 
3.7 
Safety Analyses 
The safety analysis will be conducted on the Safety Set.   
The study team has decided not to present the following safety endpoints analyses in the 
abbreviated CSR: 
• Echocardiogram and DEXA  
• Ultrasound and MRI assessment for spleen, and bone marrow 
• Leg Ulcers 
3.7.1 Adverse Events 
The incidence of AEs will be summarized by Medical Dictionary for Regulatory Activities 
(MedDRA) version 22.0 (or higher) preferred term and system organ class for: 
• Any treatment-emergent adverse events (TEAEs) 
• Related TEAEs. Related is defined as “Related”, “Possible”, or missing relationship 
to study drug  
• Any TEAEs by severity. At each level of subject summarization, a subject is 
classified according to the highest severity if the subject reported one or more events. 
Adverse events with missing severity will categorized as “Missing” for this summary 
• Serious TEAEs (SAEs) 
• TEAEs leading to permanent study drug discontinuation 
SAEs and non-serious AEs that lead to study discontinuation or study drug discontinuation will 
be listed separately.  All AEs, including SAEs, will be presented in a subject listing, and 
non-treatment-emergent adverse event will be noted in the listing. 
To determine the AE as treatment-emergent or not, if there is no “Formlink” link, and the AE 
(start date/time) occurs after the subject’s first dosing date/time, then the AE is 
“treatment-emergent”. Otherwise, if the AE (start date/time) occurs prior to the subject’s first 
dosing date/time, then the AE is not treatment-emergent.  

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In addition, if there is a “Formlink” link between two AE records, the 2 records will be analyzed 
pairwise.  Consider the following 2 cases, where the AE severity (mild/moderate/severe) are 
compared between the 2 records in the pair.  The 2 records will be ordered chronologically (by 
AE start date) and referred to the “first” and “second” AE.   
Case 1:  The first AE record in the pair occurs before first dosing, and the second record 
occurs after first dosing.   
If the AE severity of the second record is worse than that of the first record, then only the 
second AE is deemed a TEAE. Otherwise, neither record is considered as TEAE. 
Case 2:  Both AE records in the pair occur after first dosing.   
The worst AE record will be deemed a TEAE. 
All TEAEs identified based on the rules above will be summarized in the event number analysis.    
The most conservative approach will be used to determine if the event occurs after the treatment.  
For example, if the onset date or resolution date of an AE is prior to the first study treatment 
date, it will be considered to have occurred prior to the study period.  If the onset or resolution 
date of an AE is a partial date with only month or year available or completely missing, then the 
event is assumed to be within the study period unless the year is prior to the year of the first 
study treatment date, or if in the same year, the month is prior to the month of the first study 
treatment date. 
Handling of Missing Data  
If the date of adverse events or prior/concomitant medications is completely or partially missing, 
the data will be imputed by the rules below.  
For AEs, the following imputation rules will be applied to impute start dates under conservative 
principles: 
• If year, month and day are all missing then assign the date of first dose of Study Drug 
• If month and day are missing and year is: 
o the same as the year of the first dose of Study Drug then assign the month-day of 
first Study Drug 
o earlier than the year of the first dose of Study Drug then assign December 31 
o after the year of the first dose of Study Drug then assign January 1 
• If only day is missing and month-year is: 
o the same as the month-year of the first dose of Study Drug then assign the day of 
first Study Drug 
o earlier than the month-year of the first dose of Study Drug then assign the last day 
of the month 

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o after the month-year of the first dose of Study Drug then assign the first day of the 
month 
Imputation will be performed only for the end date only if the day or month is missing (i.e., year 
is present) for a resolved AE as follows: 
• If month and day are missing and year is 
o the same as the year of the last dose of Study Drug then assign the month-day of 
the last dose of Study Drug 
o otherwise, assign December 31 
• If only day is missing then assign the last day of the month 
If the imputed start date is later than the imputed end date then set the imputed start date to the 
imputed end date. 
For prior/concomitant medications, the following imputation rules will be applied to impute start 
dates under conservative principles: 
• If year, month and day are all missing then assign the date of first dose of Study Drug 
• If month and day are missing and year is: 
o earlier than the year of the first dose of Study Drug then assign December 31 
o otherwise, assign January 1 
• If only day is missing and month-year is: 
o earlier than the month-year of the first dose of Study Drug then assign the first 
day of the month 
o otherwise, assign the last day of the month 
Imputation will be performed only for the end date only if the day or month is missing (i.e., year 
is present) for a stopped prior/concomitant medication as follows: 
• If month and day are missing then assign December 31 
• If only day is missing then assign the last day of the month 
If the imputed start date is later than the imputed end date then set the imputed start date to the 
imputed end date. 
Local Cutaneous Reactions at the Injection Site 
Local cutaneous reactions at the injection site (LCRIS) is defined as (A) moderate or severe 
adverse events with the preferred terms (PTs) including Injection site erythema, Injection site 
swelling, Injection site pruritus, or Injection site pain that started on the day of injection, 
persisted for at least 2 days or ongoing; or (B) any AE at the Study Drug injection site, regardless 
of severity, that leads to discontinuation of study drug, where AE at the Study Drug injection site 
is the principal reason for discontinuation. 

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Percentage of injections leading to LCRIS will be calculated as follows for each subject: 
(A/B)*100, where A = number of injections with an LCRIS, and B = total number of injections. 
Doses that are split across multiple injections are counted as a single injection. 
LCRIS will be summarized using the MedDRA coding system, by System Organ Classes (SOCs) 
and PTs.  Percentage of injections leading to LCRIS will also be summarized.  
LCRIS will be listed. 
Flu-like Reactions 
Flu-like reactions (FLR) will also be summarized using the MedDRA coding system, by SOCs 
and PTs. 
Flu-like reactions are defined as adverse events with PTs including either (A) Influenza like 
illness or (B) Pyrexia or Feeling hot or Body temperature increased, plus at least 2 of the 
following symptoms with the PTs: Chills, Myalgia, or Arthralgia starting on the day of injection 
or the next day.  
Percentage of injections leading to flu-like reactions will be summarized using the descriptive 
statistics and calculated as follows for each subject:  (A/B)*100, where A = number of injections 
leading to flu-like reactions, and B = total number of injections.  Note that doses that are split 
across multiple injections are counted as a single injection.  
Percentage of injections leading to FLRs will also be summarized.  
FLRs will be listed. 
AE of special interest (AESI) 
There is no AESI for this study.  
3.7.2 Vital Signs Measurements 
Vital signs will include weight, respiratory rate, body temperature, BMI, and systolic and 
diastolic blood pressure.  All vital signs will be summarized by treatment cohort for vital sign 
values as well as the change and percent change from baseline at each post-baseline visit.   
3.7.3 Laboratory Measurements 
Chemistry, hematology, coagulation, complement, and urinalysis (result, mean change, and mean 
percent change from baseline) will be summarized by treatment cohort and each post-baseline 
visit.  For urinalysis, only Protein, Creatinine, and protein-to-creatinine (P/C) ratio will be 
summarized.  Listing of laboratory assessments in Chemistry, Hematology, and urinalysis will be 
provided.  Local laboratory data will also be provided in the listings separately. 
For ALT and AST, the number and percent of patients in each of the following categories will be 
tabulated by treatment cohort:  

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 ALT/AST > 3 × ULN, confirmed 
 ALT/AST > 5 × ULN, confirmed 
A confirmed value is based on a consecutive lab value performed on a different day to, but 
within 7 days of, the initial value.  If the repeated value is in the same or worse category, then the 
initial value is considered confirmed.  If the consecutive value is in a better category, then the 
initial value is confirmed using the consecutive value category.  If values that are not confirmed 
due to failure to retest or missing lab values, then the initial value is presumed confirmed.  
If there are multiple results on the same day (no matter from the same lab vendor or different lab 
vendors), then the worst value will be utilized in the analysis. 
The number and percent of subjects in the following confirmed nadir platelet counts categories 
will be summarized by treatment cohort: 
 100,000 to < 120,000/mm3 
 75,000 to < 100,000/mm3 
 50,000 to < 75,000/mm3 
 25,000 to < 50,000/mm3 
 < 25,000/mm3  
Subjects with more than one confirmed value will be counted exactly once under the worst 
confirmed category. 
3.7.4 Exposure and Drug Administration 
Treatment duration and amount of Study Drug received will be summarized by treatment cohort. 
The treatment duration for each subject is defined as last treatment dose date – first treatment 
dose date + 1. 
The time on study will be defined as the total number of days a subject is known to be followed 
on study calculated as follows:  
Time on study = Last date on study – Date of first dose + 1, 
where the last date on study is defined as the date of the latest visit with evaluation for a given 
subject.  Visits with refused or unable to contact are not visits with evaluation. 
 
 

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The duration of exposure to ISIS 702843 will be summarized at each dose level for patients 
receiving ≥ 1 dose, ≥ 7 doses, and ≥ 13 doses every 4 weeks without interruption, to capture 
exposure to ISIS 702843 ≥ 1 month, ≥ 6 months, and ≥ 12 months, respectively. 
The data of drug administration will be presented in listings, including dosing information, dose 
pause, etc.  
3.7.5 12-Lead Electrocardiograms (ECG) 
Safety 12 lead ECG will be performed in triplicate at the visits indicated in the protocol 
Appendix A, Schedule of Activities.   
The ECG data will include ventricular rate (VR), PR interval, QRS duration, QT, and corrected 
QT intervals, and overall interpretation.  
For the continuous variables above, descriptive statistics (n, mean, standard error, standard 
deviation, median, 25th percentile, 75th percentile, minimum and maximum) of the average of 
triplicate results at each study visit, as well as the change and percent change from Baseline to 
each study visit, will be summarized by treatment cohort ; for the categorical responses to overall 
interpretation, the worst of triplicate results and the associated findings at each visit will be 
summarized by counts and percentages.  All the ECG data collected in triplicate will be listed.  
3.7.6 Prior and Concomitant Medications 
Prior and concomitant medications will be coded using WHO Drug dictionary (version March 
2019 or later) and summarized by Anatomical Therapeutic Chemical (ATC) class, preferred 
terms and, by treatment cohort.  Ancillary procedures, if available, will also be summarized. 
As for the usage of chelation, in addition to the analyses specified in Section 3.5, the data will be 
summarized in the same way as prior and concomitant medications. 
3.7.7 MRI 
The MRI assessments for liver will be summarized at scheduled visits by treatment cohort.  The 
data of LIC will be included in the MRI assessments. 
Listings of the MRI assessments will also be provided. 
3.7.8 Genetic Sample 
The data of genetic sample will be presented in a by-patient listing.  

Ionis Pharmaceuticals, Inc. 
CONFIDENTIAL 
22 May 2023
Statistical Analysis Plan 
ISIS 702843-CS2
 
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4 
REFERENCES 
Shankar G, Arkin S, Cocea L, Devanarayan V, Kirshner S, Kromminga A, Quarmby V, Richards 
S, Schneider CK, Subramanyam M, et al. Assessment and reporting of the clinical 
immunogenicity of therapeutic proteins and peptides-harmonized terminology and tactical 
recommendations. Aaps J. 2014;16:658–73. 
Wang YM C, Wang J, Hon YY, Zhou L, Fang L, and Ahn HY.  Evaluating and Reporting the 
Immunogenicity Impacts for Biological Products—a Clinical Pharmacology Perspective. AAPS 
J. 2016; 18(2): 395-403.    

Version: 2
Version Date: 24 May 2023
Title: 702843-CS2 SAP V3 22May2023