An Open-Label Extension Study To Evaluate The Long- Term Safety And Tolerability Of Daxdilimab (Hzn-7734) In Subjects With Systemic Lupus Erythematosus
Phase: PHASE2
Conditions: Systemic Lupus Erythematosus
Sponsor: Amgen

Protocol: HZNP-DAX-204 
Daxdilimab (HZN-7734) 
Horizon Therapeutics Ireland DAC 
Date: 17 March 2022 
AN OPEN-LABEL EXTENSION STUDY TO EVALUATE THE LONG-
TERM SAFETY AND TOLERABILITY OF DAXDILIMAB (HZN-7734) IN 
SUBJECTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS 
SHORT TITLE: RECAST SLE OLE 
Investigational Product 
Protocol Number 
Clinical Trial Registry 
Identifiers 
Version 
Version Date 
IND Number 
Lead Principal Investigator 
Sponsor 
daxdilimab (also known as HZN-7734 and VIB7734); an 
anti-ILT7 monoclonal antibody for depletion of 
plasmacytoid dendritic cells 
HZNP-DAX-204 
clinicaltrials.gov: TBD 
EudraCT: 2022-000855-35 
original protocol, version 1 
17Mar2022 
IND 127898 
TBD 
Horizon Therapeutics Ireland DAC 
70 St. Stephen's Green 
Dublin 2, Ireland 
D02 E2X4 
Responsible Medical Officer 
,MD 
Executive Medical Director 
Horizon Therapeutics 
1 Medimmune Wa , Gaithersburg, MD, 20878 
Telephone: 
NCT Number: NCT05430854 
This NCT number has been applied to the document 
for purposes of posting on Clinicaltrials.gov 
CONFIDENTIAL AND PROPRIETARY 
Page 1 of84 

Protocol: HZNP-DAX-204 
Horizon Therapeutics Ireland DAC 
Daxdilimab (HZN-7734) 
Date: 17 March 2022 
 
CONFIDENTIAL AND PROPRIETARY 
Page 3 of 84 
TABLE OF CONTENTS 
PROTOCOL VERSION HISTORY .............................................................................................. 2 
TABLE OF CONTENTS ............................................................................................................... 3 
LIST OF FIGURES ....................................................................................................................... 8 
LIST OF TABLES ......................................................................................................................... 8 
STATEMENT OF COMPLIANCE ............................................................................................... 9 
SIGNATURE PAGE ................................................................................................................... 10 
PRINCIPAL/QUALIFIED INVESTIGATOR SIGNATURE PAGE ......................................... 11 
LIST OF ABBREVIATIONS ...................................................................................................... 12 
1 
PROTOCOL SUMMARY ............................................................................................... 15 
1.1 
Synopsis ........................................................................................................................ 15 
1.2 
Schema .......................................................................................................................... 18 
1.3 
Schedule of Activities ................................................................................................... 19 
2 
INTRODUCTION ........................................................................................................... 23 
2.1 
Study Rationale ............................................................................................................. 23 
2.2 
Background ................................................................................................................... 24 
2.2.1 
Systemic Lupus Erythematosus ................................................................................. 24 
2.2.2 
Unmet Need ............................................................................................................... 25 
2.2.3 
Daxdilimab ................................................................................................................. 25 
2.2.4 
Supportive Nonclinical Data ...................................................................................... 26 
2.2.5 
Supportive Clinical Data ............................................................................................ 26 
2.2.5.1 
Phase 1 Single-Ascending Dose Study in Subjects with Autoimmune 
Diseases .................................................................................................................. 27 
2.2.5.2 
Phase 1b Multiple-Ascending Dose Study in Subjects with Autoimmune 
Diseases .................................................................................................................. 27 
2.3 
Benefit/Risk Assessment .............................................................................................. 27 
2.3.1 
Risk Assessment ........................................................................................................ 28 
2.3.1.1 
COVID-19 Risk Assessment .................................................................................. 28 
2.3.2 
Benefit Assessment .................................................................................................... 28 
2.3.3 
Overall Benefit-Risk Conclusion ............................................................................... 29 
3 
OBJECTIVES AND ENDPOINTS ................................................................................. 29 
4 
STUDY DESIGN............................................................................................................. 30 
4.1 
Overall Design .............................................................................................................. 30 

Protocol: HZNP-DAX-204 
Horizon Therapeutics Ireland DAC 
Daxdilimab (HZN-7734) 
Date: 17 March 2022 
 
CONFIDENTIAL AND PROPRIETARY 
Page 4 of 84 
4.2 
Scientific Rationale for the Study Design ..................................................................... 31 
4.2.1 
Rationale for Study Population .................................................................................. 31 
4.2.2 
Rationale for the Primary Outcome Measure ............................................................ 31 
4.2.3 
Rationale for the Secondary Outcome Measure ........................................................ 31 
4.3 
Rationale for Dose ........................................................................................................ 32 
4.4 
End-of-Study Definition ............................................................................................... 32 
5 
STUDY POPULATION .................................................................................................. 32 
5.1 
Inclusion Criteria .......................................................................................................... 32 
5.2 
Exclusion Criteria ......................................................................................................... 33 
5.3 
Lifestyle Considerations ............................................................................................... 34 
5.4 
Screen Failures .............................................................................................................. 34 
5.5 
Criteria for Temporarily Delaying Enrollment or Administration of 
Investigational Product ................................................................................................. 34 
6 
INVESTIGATIONAL PRODUCT AND CONCOMITANT THERAPY ...................... 34 
6.1 
Investigational Product Administered ........................................................................... 34 
6.2 
Preparation, Handling, Storage, and Accountability .................................................... 35 
6.2.1 
Preparation/Storage/Handling .................................................................................... 35 
6.2.1.1 
Inspection and Storage ............................................................................................ 35 
6.2.1.2 
Investigational Product Dose Preparation ............................................................... 36 
6.2.1.3 
Investigational Product Dosing, Administration, and Monitoring.......................... 36 
6.2.1.4 
Handling and Disposal ............................................................................................ 37 
6.2.2 
Accountability ............................................................................................................ 37 
6.3 
Assignment to Investigational Product ......................................................................... 37 
6.4 
Blinding......................................................................................................................... 37 
6.5 
Investigational Product Compliance ............................................................................. 37 
6.6 
Dose Modification ........................................................................................................ 37 
6.7 
Continued Access to Investigational Product After the End of the Study .................... 37 
6.8 
Treatment of Overdose or Misuse ................................................................................. 38 
6.9 
Prior and Concomitant Therapy .................................................................................... 38 
6.9.1 
Permitted Concomitant Therapy ................................................................................ 38 
6.9.1.1 
Concomitant Medications and Treatments ............................................................. 38 
6.9.1.2 
Concomitant Medications for Systemic Lupus Erythematosus Standard of 
Care During the Study ............................................................................................ 38 

Protocol: HZNP-DAX-204 
Horizon Therapeutics Ireland DAC 
Daxdilimab (HZN-7734) 
Date: 17 March 2022 
 
CONFIDENTIAL AND PROPRIETARY 
Page 5 of 84 
6.9.2 
Prohibited Concomitant Medications ........................................................................ 41 
6.9.3 
Medications and Therapies That Lead to Immediate Discontinuation of 
Investigational Product .............................................................................................. 41 
6.9.4 
Restricted Medications............................................................................................... 42 
7 
DISCONTINUATION OF INVESTIGATIONAL PRODUCT AND SUBJECT 
DISCONTINUATION/WITHDRAWAL........................................................................ 43 
7.1 
Discontinuation of Investigational Product .................................................................. 43 
7.2 
Subject Discontinuation/Withdrawal from the Study ................................................... 44 
7.3 
Lost to Follow-up .......................................................................................................... 44 
8 
STUDY ASSESSMENTS AND PROCEDURES ........................................................... 45 
8.1 
Administrative and General Procedures ....................................................................... 45 
8.3 
Safety Assessments ....................................................................................................... 50 
8.3.1 
Physical Examinations ............................................................................................... 50 
8.3.2 
Vital Signs .................................................................................................................. 50 
8.3.3 
Electrocardiograms .................................................................................................... 50 
8.3.4 
Local Injection Tolerability Assessments .................................................................. 51 
8.3.5 
Clinical Safety Laboratory Tests ............................................................................... 51 
8.3.5.1 
Hepatitis B Assessments ......................................................................................... 53 
8.3.6 
Pregnancy Testing ...................................................................................................... 53 
8.4 
Adverse Events, Serious Adverse Events, and Other Safety Reporting ....................... 53 

Protocol: HZNP-DAX-204 
Horizon Therapeutics Ireland DAC 
Daxdilimab (HZN-7734) 
Date: 17 March 2022 
 
CONFIDENTIAL AND PROPRIETARY 
Page 6 of 84 
8.4.1 
Definitions.................................................................................................................. 53 
8.4.2 
Adverse Event Reporting ........................................................................................... 54 
8.4.3 
Classification of an Adverse Event ............................................................................ 55 
8.4.3.1 
Causality or Relatedness ......................................................................................... 55 
8.4.3.2 
Severity or Intensity ................................................................................................ 55 
8.4.4 
Time Period and Frequency for Collecting AE and SAE Information ...................... 56 
8.4.5 
Method of Detecting AEs and SAEs ......................................................................... 56 
8.4.6 
Follow-up of AEs and SAEs ...................................................................................... 56 
8.4.7 
Regulatory Reporting Requirements for SAEs .......................................................... 56 
8.4.8 
Pregnancy ................................................................................................................... 57 
8.4.9 
Adverse Events of Special Interest ............................................................................ 58 
8.4.10 
Overdose or Misuse ................................................................................................... 58 
8.5 
Pharmacokinetics .......................................................................................................... 58 
8.6 
Pharmacodynamics ....................................................................................................... 59 
8.7 
Genetics......................................................................................................................... 59 
8.8 
Exploratory Biomarker Evaluation ............................................................................... 59 
8.9 
Immunogenicity Assessments ....................................................................................... 59 
9 
STATISTICAL CONSIDERATIONS............................................................................. 60 
9.1 
Primary Hypothesis ....................................................................................................... 60 
9.2 
Analysis Sets ................................................................................................................. 60 
9.3 
Statistical Analyses ....................................................................................................... 61 
9.3.1 
General Considerations .............................................................................................. 61 
9.3.2 
Primary Endpoint(s) Analysis .................................................................................... 61 
9.3.2.1 
Safety Analysis ....................................................................................................... 61 
9.3.3 
Secondary Endpoint(s) Analysis ................................................................................ 61 
9.3.3.1 
Pharmacokinetics Analysis ..................................................................................... 61 
9.3.3.2 
Immunogenicity Analysis ....................................................................................... 61 
9.3.3.3 
Pharmacodynamics Analysis .................................................................................. 61 

Protocol: HZNP-DAX-204 
Horizon Therapeutics Ireland DAC 
Daxdilimab (HZN-7734) 
Date: 17 March 2022 
 
CONFIDENTIAL AND PROPRIETARY 
Page 7 of 84 
9.3.4 
Exploratory Endpoint(s)Analyses .............................................................................. 61 
9.4 
Interim Analysis ............................................................................................................ 62 
9.5 
Sample Size Determination........................................................................................... 62 
10 
SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS ....................................................................................................... 63 
10.1 
Appendix 1: Regulatory, Ethical, and Study Oversight Considerations ....................... 63 
10.1.1 
Regulatory and Ethical Considerations ...................................................................... 63 
10.1.2 
Financial Disclosure................................................................................................... 63 
10.1.3 
Informed Consent Process ......................................................................................... 64 
10.1.4 
Data Protection and Privacy....................................................................................... 64 
10.1.5 
Committees Structure................................................................................................. 65 
10.1.5.1 
Safety Data Monitoring Committee ........................................................................ 65 
10.1.6 
Dissemination of Clinical Study Data........................................................................ 65 
10.1.7 
Biological Specimens and Data ................................................................................. 65 
10.1.8 
Data Quality Assurance ............................................................................................. 66 
10.1.8.1 
Monitoring .............................................................................................................. 66 
10.1.8.2 
Audits/Inspections................................................................................................... 67 
10.1.9 
Data Capture and Management .................................................................................. 67 
10.1.10 
Source Documents ..................................................................................................... 68 
10.1.11 
Records Retention ...................................................................................................... 68 
10.1.12 
Study and Site Start and Closure ............................................................................... 68 
10.1.13 
Publication Policy ...................................................................................................... 69 
10.2 
Appendix 2: Adverse Events and Serious Adverse Events: Definitions and 
Procedures for Recording, Evaluating, Follow-up, and Reporting............................... 70 
10.2.1 
Definition of AE ........................................................................................................ 70 
10.2.2 
Definition of SAE ...................................................................................................... 71 
10.2.3 
Recording and Follow-Up of AEs and/or SAEs ........................................................ 72 
10.2.4 
Reporting of SAEs ..................................................................................................... 72 
10.3 
Appendix 3: Contraceptive Guidance ........................................................................... 74 
10.4 
Appendix 4: Liver Safety: Suggested Actions and Follow-up Assessments ................ 75 
10.5 
Appendix 5: National Institute of Allergy and Infectious Disease and Food and 
Allergy Anaphylaxis Network Guidance for Anaphylaxis Diagnosis .......................... 76 
10.6 
Appendix 6: Study-Specified Opportunistic Infections ................................................ 77 

Protocol: HZNP-DAX-204 
Horizon Therapeutics Ireland DAC 
Daxdilimab (HZN-7734) 
Date: 17 March 2022 
 
CONFIDENTIAL AND PROPRIETARY 
Page 8 of 84 
10.7 
Appendix 7: Prednisone Equivalent of Oral Glucocorticoid Dose ............................... 78 
10.8 
Appendix 8: Recommended Oral Glucocorticoid Tapering Schedule ......................... 79 
11 
REFERENCES ................................................................................................................ 80 
 
LIST OF FIGURES 
Figure 1 
Clinical Study Diagram........................................................................................ 18 
 
LIST OF TABLES 
Table 1 
Schedule of Activities .......................................................................................... 19 
Table 2 
Primary, Secondary, and Exploratory Objectives ................................................ 29 
Table 3 
Description of Investigational Product and Dosing ............................................. 35 
Table 4 
Clinical Laboratory Tests ..................................................................................... 52 
Table 5 
CTCAE v5.0 General Guidelines ........................................................................ 56 
Table 6 
Highly Effective Methods of Contraception ........................................................ 74 
Table 7 
Study-Specified Opportunistic Infections ............................................................ 77 
Table 8 
Prednisone Equivalent of OGC Dose .................................................................. 78 
Table 9 
Recommended Oral Glucocorticoid Tapering Schedule ..................................... 79 
 

Protocol: HZNP-DAX-204 
Horizon Therapeutics Ireland DAC 
Daxdilimab (HZN-7734) 
Date: 17 March 2022 
 
CONFIDENTIAL AND PROPRIETARY 
Page 9 of 84 
STATEMENT OF COMPLIANCE 
The study will be conducted in compliance with this clinical study protocol, Good Clinical 
Practice (GCP) as outlined by International Council for Harmonisation (ICH) E6(R2), and all 
applicable local and national regulatory requirements. Enrollment at any clinical study site may 
not begin prior to that site receiving approval from the ethics committee of record for the 
protocol and all materials provided to potential participants. 
Any amendments to the protocol or changes to the consent document will be approved before 
implementation of that amendment. Reconsent of previously enrolled participants may be 
necessary depending on the nature of the amendment. 
The Principal Investigator will ensure that changes to the study plan as defined by this protocol 
will not be made without prior agreement from the Sponsor and documented approval from the 
ethics committee of record, unless such a change is necessary to eliminate an immediate hazard 
to the study participants. 
All personnel involved in the conduct of this study have completed Human Subjects Protection 
and GCP Training. 

Protocol: HZNP-DAX-204 
Horizon Therapeutics Ireland DAC 
Daxdilimab (HZN-7734) 
Date: 17 March 2022 
 
CONFIDENTIAL AND PROPRIETARY 
Page 11 of 84 
PRINCIPAL/QUALIFIED INVESTIGATOR SIGNATURE PAGE 
 
 
 
Investigator Name: 
 
 
 
Signature: 
 
Date: 
 
 
 
 
 
(DD-MMM-YYYY) 
 
Institution Name: 
 
 
 
 
By my signature, I agree to personally supervise the conduct of this study at my study site and 
to ensure its conduct in accordance with the ethical principles that have their origin in the 
Declaration of Helsinki and in compliance with the protocol, informed consent, institutional 
review board/independent ethics committee procedures, instructions from Sponsor’s 
representatives, ICH GCP guidelines, and applicable local regulations governing the conduct 
of clinical studies. 
 

Protocol: HZNP-DAX-204 
Horizon Therapeutics Ireland DAC 
Daxdilimab (HZN-7734) 
Date: 17 March 2022 
CONFIDENTIAL AND PROPRIETARY 
Page 12 of 84 
LIST OF ABBREVIATIONS  
Abbreviation 
Definition 
21 CFR 
Title 21 of the Code of Federal Regulations 
ACTH 
adrenocorticotropic hormone 
ADA 
Anti-drug antibodies 
AE(s) 
adverse event(s) 
AESI 
adverse event of special interest 
ALT 
alanine aminotransferase 
ANA 
antinuclear antibodies 
AST 
aspartate aminotransferase 
AZA 
azathioprine 
BICLA 
BILAG-based Composite Lupus Assessment 
BILAG 
British Isles Lupus Assessment Group 
CD 
cluster of differentiation 
CDM 
Clinical Data Management 
CLE 
cutaneous lupus erythematosus 
CNS 
central nervous system 
COVID-19 
coronavirus disease 2019 
CRF(s) 
case report form(s) 
CRO 
clinical research organization 
CTCAE 
Common Terminology for Adverse Events 
DC(s) 
dendritic cell(s) 
DMP 
Data Management Plan 
dsDNA 
double-stranded DNA  
ECG(s) 
electrocardiogram(s) 
eCRF(s) 
electronic case report form(s) 
ET 
early termination 
FDA 
Food and Drug Administration 
FSH 
follicle-stimulating hormone 
GCs 
glucocorticoids 
GCP 
Good Clinical Practice(s) 
GLP 
Good Laboratory Practice 

Protocol: HZNP-DAX-204 
Horizon Therapeutics Ireland DAC 
Daxdilimab (HZN-7734) 
Date: 17 March 2022 
 
CONFIDENTIAL AND PROPRIETARY 
Page 13 of 84 
Abbreviation 
Definition 
HL 
Hy’s Law 
IB 
Investigator’s Brochure 
ICF 
informed consent form 
ICH 
International Council for Harmonisation 
IEC(s) 
Independent Ethics Committee(s) 
IFN 
interferon 
Ig 
immunoglobulin 
IP 
investigational product 
IRB(s) 
Institutional Review Board(s) 
IV 
intravenous(ly) 
LN 
lupus nephritis 
mAb(s) 
monoclonal antibody(ies) 
MAD 
multiple-ascending dose 
MCP 
metacarpophalangeal 
MMF 
mycophenolate mofetil  
MPA 
mycophenolic acid 
mTOR 
mammalian target of rapamycin 
MTX 
methotrexate  
NSAID(s) 
nonsteroidal anti-inflammatory drug(s) 
NK 
natural killer 
OGC(s) 
oral glucocorticoid(s) 
OLE 
open-label extension 
OTC 
over the counter  
PD 
pharmacodynamic(s) 
pDC(s) 
plasmacytoid dendritic cell(s) 
PEF 
peak expiratory function 
PHL 
Potential Hy’s Law 
PI 
Principal Investigator 
PIP 
proximal interphalangeal 
PK 
pharmacokinetic(s) 
PRN 
as needed 
PT 
preferred term 

Protocol: HZNP-DAX-204 
Horizon Therapeutics Ireland DAC 
Daxdilimab (HZN-7734) 
Date: 17 March 2022 
 
CONFIDENTIAL AND PROPRIETARY 
Page 15 of 84 
1 
PROTOCOL SUMMARY 
1.1 
Synopsis 
Protocol Title:  
An Open-label Extension Study to Evaluate the Long-term Safety and Tolerability of 
Daxdilimab (HZN-7734) in Subjects with Systemic Lupus Erythematosus 
Short Title:  
RECAST SLE OLE 
Rationale: 
Daxdilimab (previously known as HZN-7734 or VIB7734) is being developed for the treatment 
of multiple autoimmune disorders in which plasmacytoid dendritic cells (pDCs) are believed to 
contribute to the pathogenesis including alopecia areata, dermatomyositis, discoid lupus 
erythematosus, lupus nephritis, and systemic lupus erythematosus (SLE). This is a Phase 2, 
multicenter, open-label extension (OLE) study to evaluate the long-term safety and tolerability of 
daxdilimab in subjects completing the treatment period of the RECAST SLE clinical study. 
Based on its mechanism of action, daxdilimab has the potential to decrease SLE disease activity. 
In addition, based on data currently available, daxdilimab presents an acceptable safety profile; 
therefore, it is justified to evaluate its long-term safety, pharmacokinetics (PK), and 
immunogenicity in subjects with active SLE, prior to advancing daxdilimab into larger clinical 
studies. 
Objectives and Endpoints: 
The primary and secondary objectives and associated endpoints are detailed below. For 
tertiary/exploratory objectives and endpoints, see Section 3 of this protocol. 
Table S1  
Primary and Secondary Objectives 
Objectives 
Endpoints 
Primary Objective 
To evaluate the long-term safety and 
tolerability of 200 mg Q12W daxdilimab 
Incidence of AEs, SAEs, and AESIs 
Secondary Objectives 
To characterize the PK, PD, and 
immunogenicity of daxdilimab 
Daxdilimab concentration, change in pDCs, and ADA rate 
ADA = anti-drug antibody; AEs = adverse events; AESIs = adverse events of special interest; 
PD = pharmacodynamics; pDCs = plasmacytoid dendritic cells; PK = pharmacokinetics; Q12W = every 
12 weeks; SAEs = serious adverse events 
 

Protocol: HZNP-DAX-204 
Horizon Therapeutics Ireland DAC 
Daxdilimab (HZN-7734) 
Date: 17 March 2022 
 
CONFIDENTIAL AND PROPRIETARY 
Page 16 of 84 
Overall Design: 
This is a Phase 2, multicenter, OLE study to evaluate the long-term safety and tolerability of 
daxdilimab in subjects completing the treatment period of the RECAST SLE clinical study.  
Once a subject has completed the treatment period (through Week 48) of the RECAST SLE 
study, signed the informed consent form, and met all study eligibility criteria, he/she may be 
enrolled in this OLE study. To allow for the continuous dosing of the subjects, the start of this 
OLE study should occur immediately after the completion of the RECAST SLE treatment period 
(ie, first OLE dosing [Day 1] coinciding with Week 48/Visit 14 of the RECAST SLE study). 
Any exceptions to this enrollment date must be reviewed and approved by the Medical Monitor 
before any subject is allowed to enroll after the Week 48/Visit 14 of the RECAST SLE study. 
Subjects will be treated with open-label daxdilimab 200 mg at the study site every 12 weeks 
(Q12W) subcutaneously (SC) for 48 weeks. During the treatment period, a telehealth visit (eg, 
phone or video call) will also be performed every 4 weeks between in-clinic visits to assess the 
subject’s current disease status, the OGC tapering schedule, safety, and concomitant 
medications. After the treatment period (Week 0 to Week 48), the study subjects will enter an 
8-week safety follow-up period (Week 48 to Week 56).  
The primary objective of this study is to evaluate the long-term safety and tolerability of 200 mg 
daxdilimab Q12W in adult subjects with moderately-to-severely active SLE. This will be 
assessed by summarizing adverse events (AEs), serious adverse events (SAEs), and AEs of 
special interest (AESIs). Local injection site tolerability, vital signs, physical examinations, 
electrocardiograms, and clinical laboratory tests will also be performed to support safety 
findings. 
The study will be conducted on an outpatient basis. For all administrations, daxdilimab will be 
administered by study-site staff in the clinic, and the subject will be observed for at least 
60 minutes after the first and second doses (Day 1 and Week 12) are administered to each 
subject. 
Blood samples will be collected from all subjects to characterize the PK, pharmacodynamics, 
and immunogenicity of daxdilimab. 
Number of Subjects: 
Approximately 195 subjects have been randomized in the RECAST SLE study. Assuming that 
20% of subjects will prematurely discontinue treatment, there will be a total of approximately 
156 subjects who will be eligible for this long-term safety study. 
Note: Enrolled means subjects, ‘or their legally acceptable representatives’, agreement to 
participate in a clinical study following completion of the informed consent process and 
eligibility review. Potential subjects who are screened for the purpose of determining eligibility 
for the study, but do not participate in the study, are not considered enrolled, unless otherwise 
specified by the protocol. A subject will be considered enrolled if the informed consent is not 
withdrawn prior to participating in any study activity after eligibility review. 

Protocol: HZNP-DAX-204 
Horizon Therapeutics Ireland DAC 
Daxdilimab (HZN-7734) 
Date: 17 March 2022 
 
CONFIDENTIAL AND PROPRIETARY 
Page 17 of 84 
Intervention Groups and Duration 
Subjects will receive 200 mg daxdilimab Q12W for 48 weeks (Weeks 0 [Day 1], 12, 24, 36, 
and 48). Following the final dose administration at Week 48, subjects will be followed up for an 
additional 8 weeks for a total study duration of approximately 56 weeks. 
Investigational Product: Dosage and Mode of Administration  
The investigational product (IP) is daxdilimab. Daxdilimab will be provided as a sterile liquid in 
a 2R glass vial with a nominal 1.0 mL of 100 mg/mL daxdilimab. Daxdilimab drug product is 
stored at 2℃ to 8°C in a refrigerator with adequate temperature monitoring in a location with 
limited access. 
Daxdilimab is to be administered as two 1.0-mL SC injections. 
Visit Frequency  
The study will be conducted on an outpatient basis. For scheduled study visits, subjects will 
come to the study sites on 7 occasions: Weeks 0 [Day 1], 12, 24, 36, 48, 52, and 56. For all IP 
administrations, daxdilimab will be administered by study-site staff at the study site. Subjects 
will also attend telehealth visits (phone or video call) on 8 occasions: Weeks 4, 8, 16, 20, 28, 32, 
40, and 44. 
x Study duration: approximately 56 weeks 
x Treatment duration and frequency: 48 weeks with in-clinic visits Q12W and telehealth 
visits Q4W between in-clinic visits 
x Follow-up duration and frequency: 8 weeks with 2 visits 4 weeks apart 
Data Monitoring/Other Committee: 
An external, independent Safety Data Monitoring Committee (SDMC) is responsible for 
safeguarding the interests of study subjects via review of accumulating safety data and for 
supporting study integrity and interpretability based on their review of ongoing study conduct. 
The SDMC will provide the Sponsor with recommendations for actions with respect to study 
conduct and the management of subjects treated under the study protocol. The SDMC members 
are independent of the Sponsor and any clinical research organization or organization 
collaborating with the Sponsor on the study.  
The SDMC will not be charged with any formal interim analysis, will not conduct a futility 
analysis, and will not be asked to consider early study completion for efficacy. For additional 
details, refer to the SDMC Charter.

Protocol: HZNP-DAX-204
Horizon Therapeutics Ireland DAC
Daxdilimab (HZN-7734)
Date: 17 March 2022
CONFIDENTIAL AND PROPRIETARY
Page 18 of 84
1.2
Schema
Figure 1
Clinical Study Diagram
equiv. = equivalent; HZN7734 = also known as daxdilimab (previously VIB7734 or HZN-7734); N = number of 
subjects; OGC = oral glucocorticoid; Q12W = every 12 weeks; RECAST SLE = Phase 2 Randomized, Double-
Blind, Placebo-Controlled Efficacy and Safety Study of Daxdilimab for the Treatment of Moderate to Severely 
Active Systemic Lupus Erythematosus; SC = subcutaneous(ly); W = week.

Protocol: HZNP-DAX-204 
Horizon Therapeutics Ireland DAC 
Daxdilimab (HZN-7734) 
Date: 17 March 2022 
 
CONFIDENTIAL AND PROPRIETARY 
Page 19 of 84 
1.3 
Schedule of Activities 
The tests and assessments to be conducted during the study and the timing for such tests/assessments are provided in Table 1. 
Table 1 
Schedule of Activities 
 
Treatment 
Follow-Up 
Study Day 
1 
29/57 
85 
113/141 
169 
197/225 
253 
281/309 
337 
365 
393 
Week (window) 
0 
4/8 
(± 3 d) 
12 
(± 7 d) 
16/20 
(± 3 d) 
24 
(± 7 d) 
28/32 
(± 3 d) 
36 
(± 7 d) 
40/44 
(± 3 d) 
48/ET 
(± 7 d) 
52 
(± 7 d) 
56 
(± 7 d) 
Procedure/Visit Number 
V1 a 
V2/V3 b 
V4 
V5/V6 b 
V7 
V8/V9 b 
V10 
V11/V12 b 
V13 
V14 
V15 
General Assessments/Procedures 
 
 
 
 
 
 
 
 
 
 
 
ICF 
X 
 
 
 
 
 
 
 
 
 
 
Eligibility review 
X 
 
 
 
 
 
 
 
 
 
 
Review medical history and add 
any AEs/SAEs/AESIs from 
RECAST SLE (if appropriate) 
X 
 
 
 
 
 
 
 
 
 
 
12-lead ECG (after 10 minutes rest 
in supine position) c 
X 
 
 
 
X 
 
 
 
X 
 
X 
Vital signs and weight d 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
Physical examination e 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
Laboratory Assessments 
 
 
 
 
 
 
 
 
 
 
 
Urine pregnancy test (in women of 
childbearing potential) 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
FSH g 
X 
 
 
 
 
 
 
 
 
 
 
Hepatitis B DNA testing h 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
Routine hematology and chemistry 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
HbAlc 
X 
 
 
 
X 
 
 
 
X 
 
X 

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Table 1 
Schedule of Activities 
 
Treatment 
Follow-Up 
Study Day 
1 
29/57 
85 
113/141 
169 
197/225 
253 
281/309 
337 
365 
393 
Week (window) 
0 
4/8 
(± 3 d) 
12 
(± 7 d) 
16/20 
(± 3 d) 
24 
(± 7 d) 
28/32 
(± 3 d) 
36 
(± 7 d) 
40/44 
(± 3 d) 
48/ET 
(± 7 d) 
52 
(± 7 d) 
56 
(± 7 d) 
Procedure/Visit Number 
V1 a 
V2/V3 b 
V4 
V5/V6 b 
V7 
V8/V9 b 
V10 
V11/V12 b 
V13 
V14 
V15 
Lipids (after an 8-hour fast; water 
allowed) i 
X 
 
 
 
X 
 
 
 
X 
 
 
Urinalysis and spot UPCr j 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
Confirmatory tests for hemolytic 
anemia k 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
C3 and C4 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
Anti-dsDNA antibodies 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
Anti-Smith antibodies 
X 
 
 
 
 
 
 
 
X 
 
 
ANA, anti-RNP, anti-SSA, anti-
SSB, rheumatoid factor 
X l 
 
 
 
 
 
 
 
X 
 
 
PT/INR and PTT 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
Serum IgG, IgA, IgM 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
Serum IFNα 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
hs-CRP 
X 
 
X 
 
X 
 
X 
 
X 
X 
X 
pDC FACS 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
Blood MxA 
X 
 
 
 
X 
 
 
 
X 
 
X 
Daxdilimab PK (serum) 
X 
 
X 
 
X 
 
X 
 
X 
 
X 
Daxdilimab ADA 
X 
 
X 
 
X 
 
X 
 
X 
 
X 

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c 
ECGs should be performed after vital signs are collected (Section 8.3.3).  
d 
Vital signs include systolic and diastolic blood pressure obtained after at least 5 minutes at rest in a seated position, heart rate, respiratory rate (breaths/min), 
and body temperature (Section 8.3.2). 
e 
A full physical examination should be performed at Visit 1 and Visit 13. A focused physical examination will be performed at all other in-clinic visits, and 
these should always include assessment of head, ears, eyes, nose, throat, lungs, heart, abdomen, skin, and extremities (Section 8.3.1). 
f 
Additional assessments, (eg, ECG or chest X-ray) should be performed as needed to fully obtain information needed for the 
 
g 
This test is conditional and can be performed at any in-clinic visit throughout the study if a female subject becomes postmenopausal during the OLE study 
(ie, 12 months with no menses without an alternative medical cause, unless on postmenopausal hormone replacement therapy) (Section 5.1). 
h 
Reflex DNA testing if isolated hepatitis B core positive in RECAST SLE (Section 8.3.5.1). Investigational product will be discontinued if the subject’s HBV 
DNA levels are confirmed to exceed the LLOQ as per the central laboratory. 
i 
This visit is recommended to occur in the morning. 
j 
Aim to collect urine at the same time of day, if possible. Urine collection can be postponed for up to 14 days in women with menstrual bleeding or a urinary 
tract infection at the scheduled visit.  
k 
Serum aliquots will be used if needed to confirm suspected hemolytic anemia. 
l 
ANA only 
m Questionnaires are strongly recommended to be completed before any other procedures are performed (Section 8.10). 
 

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2 
INTRODUCTION 
2.1 
Study Rationale  
In the absence of exogenous triggers, dendritic cells (DCs) contribute to the clearance of dying 
cells and the maintenance of tolerance (Klarquist et al, 2016; Huang et al, 2015). However, 
during infection or in the context of autoimmunity, DCs play a key role in activating cluster of 
differentiation (CD)4 and CD8 T cells. Plasmacytoid DCs (pDCs) are also known for their 
capacity to produce vast amounts of interferon alpha (IFNα) via engagement of toll-like 
receptors (TLRs) in response to viruses, including virus-derived nucleic acids, and in response to 
lupus-related, nucleic acid-containing immune complexes (Siegal et al, 1999). While pDCs from 
healthy donors have been shown to induce suppressive T-regulatory cell features (Foxp3 
expression) in vitro, systemic lupus erythematosus (SLE) pDCs failed to do so (Jin et al, 2010). 
In mouse models, constitutive depletion of pDCs in lupus-prone mice resulted in markedly 
reduced type I IFN production, a reduced IFN signature, reduced autoantibody production, and 
reduction in the severity of kidney pathology glomerulonephritis (Rowland et al, 2014). 
Importantly, transient pDC depletion during the early stages of disease was sufficient to 
significantly alter the course of the disease, suggesting a more prominent role for pDCs in the 
induction of the disease than in disease pathogenesis at later stages of disease (Rowland et al, 
2014). Recent data from Phase 2 and Phase 3 studies with IFNα pathway-blocking agents 
(sifalimumab and anifrolumab) as well as another pDC antagonist (BIIB059) demonstrated 
improvement in SLE or cutaneous lupus disease activity, further supporting the rationale for 
blocking the IFN pathway and pDCs in patients with SLE (Furie et al, 2017; Furie et al, March 
2019; Furie et al, November 2019; Khamashta et al, 2016; Morand et al, 2020; Werth et al, 
2020). 
Altogether, given the lack of highly efficacious and safe treatments for active SLE and the 
significant impact of this disease on health-related quality of life, in part from SLE-associated 
fatigue, cognitive dysfunction, and mood disorders, there is currently a significant unmet need 
for new targeted therapies. 
Based on its mechanism of action (Section 2.2.3), daxdilimab has the potential to decrease SLE 
disease activity. In addition, based on data currently available, daxdilimab presents an acceptable 
safety profile; therefore, it is justified to evaluate its long-term safety, pharmacokinetics (PK), 
and immunogenicity in subjects with active SLE, prior to advancing daxdilimab into larger 
clinical studies. 
The RECAST SLE study (VIB7734.P2.S1) is a Phase 2 randomized, double-blind, placebo-
controlled efficacy and safety study of daxdilimab for the treatment of moderately-to-severely 
active systemic SLE. The study is enrolling approximately up 195 subjects. The SLE open-label 
extension (OLE) study (HZN-DAX-204) is a long-term OLE study of daxdilimab plus standard 
of care in subjects who complete the treatment period of the RECAST SLE protocol. Irrespective 
of their assigned treatment in the RECAST SLE study, all subjects participating in the OLE will 
be treated with daxdilimab subcutaneously (SC) every 12 weeks (Q12W) in addition to their 
standard-of-care SLE therapy. 

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2.2 
Background 
2.2.1 
Systemic Lupus Erythematosus  
Clinical Presentation 
Systemic lupus erythematosus is an autoimmune disease that affects multiple organ systems and 
is unpredictable in disease severity, with periods of illness or flares alternating with periods of 
remission. The diverse presentation of lupus can range from rash and arthritis; anemia and 
thrombocytopenia; to serositis, nephritis, seizures, and psychosis. At its onset, SLE may involve 
one or more organ systems, including the musculoskeletal, cutaneous, vascular, renal, 
pulmonary, hematological, and nervous systems. Additional manifestations may occur over time. 
Disease prevalence is approximately one in 1000 individuals overall but varies with race and 
ethnicity. Systemic lupus erythematosus is more common in women than in men (9:1 ratio), and 
is more common in African American, African Caribbean, Hispanic, and Asian populations than 
Caucasians (Helmick et al 2008; Feldman et al, 2013). Onset in women typically occurs during 
their childbearing years. Patients with SLE rate their health-related quality of life as significantly 
worse than patients with common chronic diseases, such as hypertension and diabetes (Jolly, 
2005), and they are chronically exposed to medication with significant side effects, such as, 
glucocorticoids (GCs) (typically prednisone or prednisolone) and immunosuppressive agents 
(King and Hahn, 2007). Fatigue, cognitive dysfunction, and depressed mood and anxiety are 
frequent debilitating comorbidities in patients with SLE and are associated with decreased 
health-related quality of life (Yurkovich et al, 2014; Saphnelo® USPI, 2021; Holloway et al, 
2014; Lateef and Petri, 2012; Palagini et al, 2013). 
Pathogenesis and Pathology 
The pathogenesis of SLE is based on mechanisms that lead to loss of tolerance against nuclear 
autoantigens (Liu and Anders, 2014). Systemic lupus erythematosus develops when 
autoimmunization occurs against nuclear autoantigens (eg, by impairing lymphocyte depletion 
via apoptosis, opsonization, and rapid phagocytic clearance). Subsequently, endogenous nucleic 
acids directly activate TLRs on DCs or B cells that in turn drive IFNα-driven immunity, antigen 
presentation, and the activation of autoreactive lymphocyte subsets. Activation of B cells and 
their maturation to plasma cells promotes autoantibody production. Complement activation and 
proinflammatory cytokines drive the inflammatory process that can cause organ injury, scarring, 
and chronic disease. 
The production of autoantibodies to a variety of nuclear antigens is a hallmark of SLE that 
accounts for some of the pathological findings (Rahman and Isenberg, 2008; Jimenez et al, 2003; 
Petri et al, 2009). Serologically, a series of these autoantibodies are used routinely in clinical 
practice to further characterize the disease and risk for potential manifestations. These include 
antinuclear antibodies (ANA), as well as anti-double-stranded DNA (dsDNA), anti-Ro (anti-
Sjögren’s syndrome-related antibody A), anti–La (anti-Sjögren’s syndrome-related antibody B), 
anti-Smith, anti-ribonucleoprotein, and anti-ribosomal P antibodies. Histological results have 
shown association between the presence of autoantibodies and tissue damage. Levels of 
anti-dsDNA antibodies have been shown to be highly specific for SLE, correlate with disease 
activity, and may be correlated with renal involvement. 

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2.2.2 
Unmet Need 
Glucocorticoids remain a therapeutic mainstay for short- and long-term control of disease 
activity in SLE and lupus nephritis (LN) and are often administered in combination with 
chloroquine derivatives (ie, antimalarials, including hydroxychloroquine sulfate) and 
immunosuppressants (eg, mycophenolate mofetil [MMF], methotrexate [MTX], azathioprine 
[AZA], cyclophosphamide, and cyclosporine) (King and Hahn, 2007; Petri, 2006). The 
chloroquine derivatives are of moderate effectiveness and may prevent flares, though 
breakthrough flares occur frequently, while the toxicity of the more aggressive drug regimens for 
SLE contributes significantly to morbidity and mortality (King and Hahn, 2007; Petri, 2006; 
Ruiz-Arruza et al, 2014; Doria et al, 2014). 
Recently, more targeted therapies (ie, monoclonal antibodies [mAbs]), have been used in the 
treatment of SLE. Inhibition of B-lymphocyte stimulator (also known as B-cell activating factor 
of the tumor necrosis factor family) with belimumab (Benlysta®) was shown to be safe and 
effective for SLE treatment (Furie et al, 2011; Navarra et al, 2011). Belimumab was approved in 
United States (US) by the Food and Drug Administration (FDA) in 2011 and in Canada and 
Europe for treatment of SLE. Belimumab with standard of care demonstrated an increased rate of 
treatment response in SLE subjects compared to those receiving placebo and standard of care. In 
addition, results suggested that there was a reduced likelihood of severe flares and reduction in 
GC doses. However, approximately 50% of the subjects did not respond with a decrease in SLE 
activity when treated with belimumab. Another mAb, anifrolumab-fnia (Saphnelo®), which binds 
to subunit 1 of the type I IFN receptor, was approved in US by the FDA in 2021 for the treatment 
of adult patients with moderate to severe SLE who are receiving standard-of-care therapy 
(Saphnelo® USPI, 2021). In the first Phase 3 study with anifrolumab (TULIP-1), a reduction in 
oral corticosteroid dose and Cutaneous Lupus Erythematosus Disease Area and Severity Index 
(CLASI) activity scores and the achievement of British Isles Lupus Assessment Group (BILAG)-
based Composite Lupus Assessment (BICLA) responses suggested a clinical benefit for subjects 
treated with anifrolumab (Furie et al, November 2019). The second Phase 3 study with 
anifrolumab (TULIP-2) also showed a difference in BICLA response between anifrolumab and 
placebo groups (Morand et al, 2020). However, the percentage of anifrolumab-treated subjects 
who had a BICLA response or a reduction in CLASI activity score of at least 50% in either study 
was below 50% (Furie et al, November 2019; Morand et al, 2020). 
Therefore, there is a very high unmet medical need for novel, targeted therapies with improved 
efficacy and benefit-risk ratio. 
2.2.3 
Daxdilimab 
Daxdilimab is a human immunoglobulin (Ig)G1κ afucosylated mAb specific for human ILT7, a 
cell surface protein expressed by pDCs (Cho et al, 2008; Karnell et al, 2021; Rissoan et al, 
2002). Daxdilimab binding to ILT7 on the surface of pDCs leads to recruitment of macrophages 
and natural killer (NK) cells, thus inducing apoptosis and reducing the number of pDCs. The 
afucosylation of daxdilimab is designed to improve the in-life potency of the molecule and to 
enhance the capacity for antibody-dependent cellular toxicity against pDCs. 

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2.2.4 
Supportive Nonclinical Data 
ILT7 is expressed only on the pDCs of humans and nonhuman primates; therefore, the 
cynomolgus monkey was selected as the relevant species for safety evaluation of daxdilimab. 
Study 8311616 was a Good Laboratory Practice (GLP)-compliant, repeat-dose study in 
cynomolgus monkeys administered daxdilimab at 200 mg/kg intravenously (IV), 200 mg/kg SC, 
and 400 mg/kg SC once weekly for 4 weeks (5 doses). No daxdilimab-related clinical 
observations, body weight changes, ophthalmic observations, physical examination observations, 
macroscopic observations, or changes in blood pressure or electrocardiograms (ECGs) were 
observed. Daxdilimab administration had no clear or consistent group effects on clinical 
pathology parameters. Daxdilimab-related mild to moderate decreases of the group mean, 
absolute, and relative values of NK cells were observed in males given 200 or 400 mg/kg SC and 
in females given 200 mg/kg IV or SC and 400 mg/kg SC on Day 15 and Day 29 of the dosing 
phase. Daxdilimab-related pDC depletion was observed at all dose groups starting on Day 2 of 
the dosing phase. Plasmacytoid DC values were maintained at < 10% of mean baseline values in 
the majority of animals on Day 29. By Day 209, mean pDC values returned to baseline or 
approximately 50% of baseline in animals administered 200 mg/kg IV and 200 or 400 mg/kg SC, 
respectively. No other daxdilimab-related changes in peripheral blood immunophenotyping cells 
(total T cells, helper T cells, cytotoxic T cells, B cells, monocytes, and myeloid DCs) were 
observed in the blood, lymph nodes, and spleens of animals given ≥ 200 mg/kg IV or SC. 
Daxdilimab had no effect on the ability to mount a T-cell–dependent antibody response to 
primary or secondary administration of antigen, indicating intact humoral immunity during 
daxdilimab administration.  
Study 8338846 was a GLP-compliant, 6-month, repeat-dose study in cynomolgus monkeys. 
Daxdilimab was administered once weekly via SC injection for 6 months (a total of 28 doses) at 
doses of 200 and 400 mg/kg/week. There were no daxdilimab-related clinical, ophthalmic, body 
weight, or physical observations; no changes were observed in cardiac measurements or 
observations, or clinical or anatomic pathology. In addition, there were no daxdilimab-related 
effects on reproductive organs or assessments. No daxdilimab-related changes were noted for 
IgG, IgM, IgA, IgE, or peripheral blood immunophenotyping, except pDCs as expected by 
pharmacology. Daxdilimab-related depletion of mean absolute and relative values for pDCs was 
noted on Day 2 of the dosing phase in animals administered 200 or 400 mg/kg/week. The only 
daxdilimab-related observation was a minor increase in mononuclear cell and macrophage 
infiltrates at the injection sites of animals administered daxdilimab compared with controls. 
These increases were not dose dependent, and partial reversibility was noted in recovery animals.  
Based on these results, the no-observed-adverse-effect-level is 200 mg/kg when given via IV 
infusion and 400 mg/kg/week when given by SC injection. Additional details of these and other 
nonclinical studies are included in the Investigator’s Brochure (IB). 
2.2.5 
Supportive Clinical Data 
Daxdilimab has been investigated in Phase 1 single-ascending dose (SAD) and Phase 1b 
multiple-ascending dose (MAD) clinical studies in subjects with autoimmune diseases (Studies 
D6080C00001 and VIB7734.P1b.S1, respectively). Study D6080C00001 has been completed. 
Study VIB7734.P1b.S1 has a locked database, and all study-site visits have been completed. 

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2.2.5.1 
Phase 1 Single-Ascending Dose Study in Subjects with Autoimmune Diseases  
A Phase 1 SAD study (Study D6080C00001) of daxdilimab enrolled subjects with any of 
5 autoimmune diseases: dermatomyositis, polymyositis, SLE, Sjögren’s syndrome, and systemic 
sclerosis. Single SC doses of daxdilimab (1, 5, 15, 50, or 150 mg) or placebo were administered 
to 36 subjects (Karnell et al, 2021). No safety, tolerability, or immunogenicity issues were 
identified. Pharmacodynamic (PD) analysis showed a dose-dependent reduction in pDC levels, 
which was observable on Day 2 (one day after dosing on baseline [Day 1]) and maximal on 
Day 15 (Karnell et al, 2021). The duration of pDC reduction was largely dose dependent and was 
reversible in all cases. Median pDC levels returned to above 50% of baseline at the following 
time points for each cohort: 1 mg: Day 29; 5 mg: Day 57; 15 mg: Day 57; and 50 mg: Day 85. 
The time to return to above 50% of baseline could not be determined for 150 mg, since subjects 
met protocol-defined minimum absolute pDC number repletion criteria and exited the study 
before this occurred.  
2.2.5.2 
Phase 1b Multiple-Ascending Dose Study in Subjects with Autoimmune Diseases  
In a single-blind (subjects and site blinded, Sponsor unblinded), Phase 1b MAD study (Study 
VIB7734.P1b.S1), daxdilimab or placebo was administered SC every 4 weeks (Q4W) for 3 doses 
to a total of 31 subjects in 3 cohorts (Karnell et al, 2021). In the first cohort, 8 subjects with any 
of 6 autoimmune diseases (dermatomyositis, polymyositis, SLE, cutaneous lupus erythematosus 
(CLE), Sjögren’s syndrome, or systemic sclerosis) were randomized to daxdilimab (5 mg SC) or 
placebo in a 3:1 ratio. The second and third cohorts enrolled subjects with active cutaneous 
lupus, defined as a Cutaneous Lupus Erythematosus Disease Area and Severity Index-Activity 
(CLASI-A) score ≥ 8. In the second cohort, 12 subjects were randomized to daxdilimab 50 mg 
SC or placebo in a 2:1 ratio. In Cohort 3, 11 subjects were randomized to daxdilimab 150 mg SC 
or placebo in a 2:1 ratio.  
A reduction in blood pDC level was observed at the first time point after dosing (Week 1) and 
persisted through the 3-month treatment period. A high type I IFN signature was present at 
baseline in 18 of 23 subjects (78%) in Cohorts 2 and 3. The median change in IFN signature at 
Month 3 was -54% in the daxdilimab 50 mg group, -83% in the daxdilimab 150 mg group, and 
+8% in the placebo group. On the skin biopsy at Month 3, the median change in pDC density 
was -87% for the 50 mg group, -99% for the 150 mg group, and -14% for the placebo group. The 
median change in CLASI-A from baseline to Month 3 was -5 in the 50 mg group, -9.5 in the 
150 mg group, and -5 in the placebo group (Karnell et al, 2021). At Month 3, a 
≥ 50% improvement in CLASI-A was observed in 38% of subjects who received 
50 mg daxdilimab, 75% of subjects who received 150 mg daxdilimab, and 29% of subjects who 
received placebo. The proportion of subjects with an adverse event (AE) was similar in the 
daxdilimab and placebo groups (73% versus 67%, respectively). No serious AEs (SAEs) or other 
clinically important AEs occurred in daxdilimab-treated study subjects (Karnell et al, 2021). 
2.3 
Benefit/Risk Assessment 
More detailed information about the known and expected benefits and risks and reasonably 
expected AEs of daxdilimab may be found in the IB. 

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2.3.1 
Risk Assessment 
There are no important identified risks for daxdilimab. Important potential risks for daxdilimab 
may include viral infection and viral reactivation, opportunistic infection, malignancy, and 
hypersensitivity reactions, including anaphylaxis. More detailed descriptions of these potential 
risks are included in the IB. 
Hypersensitivity reactions, including anaphylaxis, are a risk associated with administration of 
biologic drugs. Definitions for these reactions can be found in Appendix 5, Section 10.5. 
Appropriate drugs and medical equipment to treat acute anaphylactic and serious 
hypersensitivity reaction must be immediately available at study sites, and study personnel must 
be competent to recognize and treat anaphylaxis. In addition, subjects will be monitored after 
investigational product (IP) administration for immediate drug reactions. Hypersensitivity 
reactions and anaphylaxis have not been observed in Phase 1 SAD and Phase 1b MAD studies. 
2.3.1.1 
COVID-19 Risk Assessment  
An additional risk of study participation includes potential exposure of the subject to severe 
acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus 
disease 2019 (COVID-19), by visiting the study site. Sites must have a plan in place to minimize 
this risk. Although testing for COVID-19 prior to Dose 1 is not required, the Investigator may 
choose to have this test performed locally in accordance with his/her judgment based on subject 
risk. This test is not provided through the study’s central laboratory, because the result of a test at 
Visit 1 would not be appropriately timed to be relevant to Dose 1. Such testing is not required. 
To minimize risk to study subjects, study sites will be activated to initiate subject enrollment 
only after review of local COVID-19 disease incidence, prevalence, containment measures, 
availability of healthcare resources, ability to monitor site activities, and the presence of a site 
plan to minimize subject exposure to SARS-CoV-2 during site visits have been confirmed.  
There are no data on the effect of daxdilimab on the risk for infection with SARS-CoV-2 or on 
the severity of COVID-19 illness.  
The current available evidence does not suggest a difference in COVID-19 infection risk in 
persons with SLE compared to the general population except for what is known about the 
increased risk that may be associated with comorbid disease and use of immunosuppressive 
treatment. 
The Investigator will assess the benefit-risk for each individual subject for determination of 
suitability for enrollment based on known risk factors for COVID-19 severity and possible or 
known exposure to SARS-CoV-2.  
Because of the evolving spread and containment measures of COVID-19, ongoing risk 
assessment will be required of participating study sites and Investigators. 
2.3.2 
Benefit Assessment 
Daxdilimab is being developed for the treatment of multiple autoimmune disorders in which 
pDCs are believed to contribute to their pathogenesis, including alopecia areata, 
dermatomyositis, discoid lupus erythematosus, LN, and SLE. The available nonclinical safety 
profile for daxdilimab is supportive of administration in subjects with SLE at exposures that do 

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not exceed those considered to be non-adverse to animals in toxicity studies performed per GLP 
guidelines (Section 2.2.4). In addition, the emerging clinical data available from two Phase 1 
studies (Study D6080C00001 [Section 2.2.5.1] and Study VIB7734.P1b.S1 [Section 2.2.5.2]) 
demonstrates an acceptable safety profile, and no adverse drug reactions have been identified.  
Given the daxdilimab mechanism of action (Section 2.2.3), the unmet need for patients with SLE 
(Section 2.2.2), and the favorable emerging data from the Phase 1 studies (Section 2.2.5), it is 
hypothesized that treatment with daxdilimab in study subjects with moderately-to-severely active 
SLE may result in maintenance or improvement in their condition as a result of participating in 
this study. Since all subjects in the study will receive unblinded, open-label daxdilimab 
irrespective of their assigned treatment in the RECAST SLE study, all study subjects have the 
potential to benefit from participating in this OLE study.  
2.3.3 
Overall Benefit-Risk Conclusion 
To date, a relatively small number of subjects have been exposed to daxdilimab across the 
ongoing clinical studies, so a full evaluation of risk/benefit is limited at present. However, no 
clinically important safety issues have emerged that preclude further evaluation of daxdilimab in 
the relevant clinical study populations at the doses chosen for this study, and the benefit-risk 
evaluation remains favorable. 
Considering the measures taken to minimize risk to subjects participating in this study, the 
potential risks identified in association with daxdilimab are justified by the anticipated benefits 
that may be afforded to study subjects with SLE. 
3 
OBJECTIVES AND ENDPOINTS 
The objectives and endpoints to be evaluated in this study are provided in Table 2. 
Table 2 
Primary, Secondary, and Exploratory Objectives 
Objectives 
Endpoints 
Primary Objective 
To evaluate the long-term safety and 
tolerability of 200 mg Q12W daxdilimab 
x 
Incidence of AEs, SAEs, and AESIs 
Secondary Objectives 
To characterize the PK, PD, and 
immunogenicity of daxdilimab 
x 
Daxdilimab concentrations, change in pDCs, and ADA rate 
Exploratory Objectives 

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4.3 
Rationale for Dose  
A 200 mg daxdilimab dose administered Q12W has been selected to evaluate whether this 
decreased frequency of daxdilimab dosing can maintain clinical efficacy and to reduce the risk of 
safety and tolerability findings in the long term.  
Treatment with daxdilimab in a single-blind, Phase 1b MAD study, resulted in a favorable safety 
profile and rapid and durable depletion of blood pDCs in all subjects receiving a 150 mg Q4W 
dose. Depletion of blood pDCs remained decreased until 3 months after the final dose when 90% 
of subjects recovered to within at least 50% of baseline. The 200 mg Q12W dosing strategy will 
allow for the evaluation of whether blood pDC depletion and recovery reaches a steady state and 
can be maintained by less frequent dosing.  
A treatment period of 48 weeks is considered sufficient to evaluate long-term safety of 
daxdilimab and the secondary PK/PD outcome measures selected for this OLE study, and current 
nonclinical (Section 2.2.4) safety data supports this treatment duration. 
4.4 
End-of-Study Definition 
An individual subject will be considered to have completed the study if the subject was followed 
up through the last protocol-specified visit, regardless of the number of doses of IP that was 
received. 
Subjects will be considered not to have completed the study if consent was withdrawn 
(Section 7.2) or the subject was lost to follow-up (Section 7.3). 
The end of the study (“study completion”) is defined as the date of the last protocol-specified 
visit/assessment for the last subject in the study. 
Information regarding site/study termination or suspension is found in Appendix 1, 
Section 10.1.12. 
5 
STUDY POPULATION  
5.1 
Inclusion Criteria 
All subjects must meet all of the following criteria to be eligible for study participation: 
1. Willing and able to understand and provide written informed consent (as described in 
Appendix 1, Section 10.1.3) prior to any study-related procedures and to comply with all 
study requirements and complete study assessments. 
2. Must have qualified for and received IP (daxdilimab or placebo) and complete the 
treatment period (through Day 337) in the RECAST SLE study. Subjects who 
discontinued early from IP in RECAST SLE are not eligible for this study. 
3. Women of childbearing potential must have a negative urine pregnancy test on Day 1. 
Women of childbearing potential are defined as those who are not surgically sterile (ie, 
surgical sterilization includes bilateral salpingectomy, bilateral oophorectomy, or 
hysterectomy) or those who are not postmenopausal (defined as 12 months with no 
menses without an alternative medical cause and a follicle-stimulating hormone [FSH] 
within the postmenopausal range as established by the central laboratory during the 

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screening period of the RECAST SLE study, unless on postmenopausal hormone 
replacement therapy). 
If a female subject becomes postmenopausal during the study (ie, 12 months with no 
menses without an alternative medical cause, unless on postmenopausal hormone 
replacement therapy), a FSH test will be performed at the central laboratory. If the FSH 
level is within the postmenopausal range, the female subject will not be required to use 
contraception after that. 
Women of childbearing potential who are sexually active with a nonsterilized male 
partner must agree to use a highly effective method of contraception from signing of the 
ICF and must agree to continue using such precautions through the end of the study 
follow-up or 3 months (approximately 5 half-lives) following the last dose of IP in the 
case of early withdrawal from the study, and refrain from egg retrieval/egg donation 
during this period. After this point, a decision about contraception should be made by the 
subject and her regular healthcare providers. Female subjects who participate in the SLE 
OLE are expected to maintain the same form of contraception they used during the 
RECAST SLE study. Effective methods of contraception are listed in Appendix 3, 
Section 10.3. 
Sustained abstinence is an acceptable practice; however, periodic abstinence, the rhythm 
method, and the withdrawal method are not acceptable methods of contraception.  
Note that because mycophenolate affects the metabolism of hormonal contraceptives and 
may reduce their effectiveness in women receiving MMF or mycophenolic acid (MPA) 
who are using hormonal contraceptives for birth control, the subject must employ an 
additional contraceptive method (eg, barrier method). 
4. Nonsterilized male subjects who are sexually active with a woman partner of 
childbearing potential must agree to use a condom with spermicide from Day 1 and until 
3 months (approximately 5 half-lives) after receipt of the last dose. Because a male 
condom with spermicide is not a highly effective contraception method, it is strongly 
recommended that male subjects advise their women partners of childbearing potential to 
use a highly effective method of contraception throughout this period. Effective methods 
of contraception are listed in Appendix 3, Section 10.3. 
 
5.2 
Exclusion Criteria  
If an individual meets any of the following criteria, he or she is ineligible for this study: 
General Criteria:  
1. Any condition or change during the RECAST SLE study that in the opinion of the 
Investigator or the Sponsor would interfere with evaluation and interpretation of subject 
safety or alter the risk-benefit associated with IP administration. 
2. Participation in another clinical study with an IP during the RECAST SLE study period. 
3. Planned elective surgeries that in the opinion of the Investigator or the Sponsor would 
interfere with evaluation and interpretation of subject safety. 
4. Any herpes zoster, cytomegalovirus, or Epstein-Barr virus infection that was not 
completely resolved prior to Visit 1. 

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5. Clinically significant active infection at Visit 1, in the opinion of the Investigator, 
including ongoing and chronic infection requiring antibiotics or antiviral medication 
(chronic nail infections are allowed). 
6. Pregnant or lactating females. 
Prior and Concomitant Therapy Criteria:  
7. Receipt of any prohibited medication during the RECAST SLE study period. Receipt of 
any restricted medications during the RECAST SLE study period must be discussed with 
the Sponsor’s Medical Monitor and agreed upon prior to enrollment into this study. 
 
5.3 
Lifestyle Considerations 
Subjects must be instructed not to take any medications, including over-the-counter (OTC) or 
herbal products or ayurvedic medications without first consulting the Investigator. Prohibited and 
permitted medications are discussed in Section 6.9. 
5.4 
Screen Failures 
A screen failure occurs when a subject who has consented to participate in the clinical study is 
not subsequently entered/enrolled in the study. A minimal set of screen failure information is 
required to ensure transparent reporting of screen failure subjects, to meet the Consolidated 
Standards of Reporting Trials publishing requirements, and to respond to queries from regulatory 
authorities. Minimal information includes screen failure details, eligibility criteria, and any 
SAEs. 
Individuals who do not meet the criteria for participation in this study (screen failure) may not be 
rescreened. These subjects will remain in and complete the SFU period of the RECAST SLE 
study. 
5.5 
Criteria for Temporarily Delaying Enrollment or Administration of Investigational 
Product 
To allow for the continuous dosing of the subjects, the start of this OLE study should occur 
immediately after the completion of the RECAST SLE treatment period (ie, first OLE dosing 
[Day 1] coinciding with Week 48/Visit 14 of the RECAST SLE study). Any exceptions to this 
enrollment date must be reviewed and approved by the Medical Monitor before any subject is 
allowed to enroll after the Week 48/Visit 14 of the RECAST SLE study. 
6 
INVESTIGATIONAL PRODUCT AND CONCOMITANT THERAPY 
6.1 
Investigational Product Administered  
The IP will be administered by study-site staff in the study site. On Day 1 and Week 12, subjects 
will remain under observation for at least one hour after IP administration. The IP will be 
provided by the Sponsor. Further details regarding the IP can be found in Table 3. 

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Table 3 
Description of Investigational Product and Dosing  
Key Information 
Investigational Product 
Product name 
Daxdilimab  
Source of procurement 
Horizon Therapeutics 
Unit dose 
strength(s)/Dosage level(s) 
200 mg dose, administered as 2 × 1.0 mL SC injections 
Route of Administration 
and frequency  
SC, Q12W for 48 weeks (Weeks 0 [Day 1], 12, 24, 36, and 48) 
Physical description 
The drug product will be provided as a sterile liquid in a 2R glass vial with a 
nominal fill volume of 1.0 mL of 100 mg/mL. 
Dosing instructions 
Daxdilimab will be administered by clinic staff trained in best practices for SC 
administration of treatments. More details on the administration method are 
described in the study manual. 
Q12W = once every 12 weeks; SC = subcutaneous; w/v = weight/volume 
The contents of the label will be in accordance with all applicable regulatory requirements. 
6.2 
Preparation, Handling, Storage, and Accountability 
The Investigator or designee must confirm appropriate conditions (eg, temperature) have been 
maintained during transit for all IP received, and any discrepancies are reported and resolved 
before use of the IP. 
Only subjects enrolled in the study may receive IP, and only authorized site staff may supply, 
prepare, or administer the IP.  
All IP must be stored in a secure, environmentally controlled, and monitored (manual or 
automated) area in accordance with the labeled storage conditions with access limited to the 
Investigator and authorized site staff. 
The Investigator or authorized site staff is responsible for IP accountability, reconciliation, and 
record maintenance (ie, receipt, reconciliation, and final disposition records). 
Further guidance and information for the final disposition of unused IP are provided in the 
Pharmacy Manual and Section 6.2.1.4. 
6.2.1 
Preparation/Storage/Handling  
6.2.1.1 
Inspection and Storage  
Each daxdilimab vial selected for dose preparation should be inspected. Any defects with the IP 
must be reported immediately to the Sponsor’s Quality Assurance Department and the site 
monitor. The Sponsor’s Quality Assurance contact information for reporting product complaints 
is: clinicalproductcomplaints@horizontherapeutics.com. During the investigation of the product 
complaint, all IP must be stored at labeled conditions unless otherwise instructed. 
Daxdilimab should be stored at 2°C to 8°C (36°F to 46°F). Labels will be prepared in accordance 
with Good Manufacturing Practice (GMP) and local regulatory guidelines. 

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Each kit has a unique number that is printed on all labels within the kit (ie, the outer carton label 
and the label on the vial within the carton). 
6.2.1.2 
Investigational Product Dose Preparation  
Preparation of daxdilimab and preparation of the syringe for SC administration are to be 
performed by an unblinded pharmacist/IP manager using aseptic technique. The same unblinded 
pharmacist/IP manager in the RECAST SLE study will perform IP and syringe preparation in 
this OLE study. 
Daxdilimab is supplied as a sterile liquid in a 2R glass vial at a nominal fill volume of 1.0 mL, 
stoppered with a 13-mm elastomeric stopper, and sealed with flip-off cap overseal. Allow the 
kits to equilibrate to room temperature about 30 minutes prior to dose preparation. 
No incompatibilities between daxdilimab and plastic syringes (ie, polypropylene and 
polycarbonate) have been observed. 
Daxdilimab does not contain preservatives and any unused portion must be discarded. Total in-
use storage time from needle puncture of the IP vial to start of administration should not exceed 
4 hours at room temperature or 24 hours at 2°C to 8°C (36°F to 46°F). If storage time exceeds 
these limits, a new dose must be prepared from new vials. 
If syringes containing IP have been stored at 2°C to 8°C (36°F to 46°F) for any length of time, 
they must equilibrate to room temperature for one hour prior to administration to the subject. 
This one-hour equilibrium period is included in the total room temperature hold time for 
prepared syringes, which must not exceed 4 hours. DO NOT FREEZE. 
A SC dose of 200 mg daxdilimab will be administered over 2 injections. To prepare each 
injection, withdraw one mL of IP into a 1 mL syringe using a 1½-inch needle. For SC dose 
administration, a 27G ½-inch needle should be used. 
6.2.1.3 
Investigational Product Dosing, Administration, and Monitoring  
The first day of dosing is considered Day 1. This is an open-label study; therefore, study-site 
staff, and subject will be unblinded. 
The same unblinded pharmacist/IP manager in the RECAST SLE study will perform IP and 
syringe preparation in this OLE study. The skin surface of the anterolateral thigh, upper outer 
triceps area, upper buttocks, or abdomen (avoiding a 2-inch [5 cm] radius around the umbilicus) 
should be prepared with an alcohol wipe and allowed to air dry. The skin will be pinched to 
isolate SC tissue from the muscle. The needle will be inserted at a 90-degree angle to the skin 
surface approximately halfway into the SC tissue. The prepared IP will be slowly injected (at 
least a 5-second duration is recommended per 1 mL syringe) into the SC tissue using gentle 
pressure. The area should not be massaged after injection. The SC injection site can be changed 
during the study as per subject preference. 
The IP should not be administered if it has been at room temperature for more than 4 hours, or if 
it has been at 2°C to 8°C (36°F to 46°F) for more than 24 hours. 
Subjects should be monitored under direct observation for at least 60 minutes after the first and 
second doses of IP administration or until the subject is stable, whichever is longer. Vital signs 
should be measured as indicated in Section 8.3.2. 

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As with any antibody, allergic reactions to dose administration are possible. Therefore, 
appropriate drugs and medical equipment to treat acute anaphylactic reactions must be 
immediately available, and study personnel must be trained to recognize and treat anaphylaxis. 
Guidance for anaphylaxis diagnosis is provided in Appendix 5, Section 10.5. 
6.2.1.4 
Handling and Disposal 
It is preferred that unused IP be destroyed at the study site after accountability and approval to 
destroy, regardless of whether the study was completed or terminated prematurely, with 
agreement from the Sponsor. 
The Investigator may return any unused vials of daxdilimab to the Sponsor or designee. At the 
time of return, the Investigator must verify, and the Study Monitor must confirm that unused or 
partially used study products have been returned and that no study products remain at the site. 
6.2.2 
Accountability  
Study-site staff will maintain a record of the IP received, dispensed, administered, and destroyed 
(if done at the site). All records will be maintained with controlled access to site, Sponsor, and 
contract research organization (CRO) staff only. A Study Monitor will perform IP accountability 
and compliance monitoring during the study. A qualified study-site staff member will only 
administer the study product to subjects included in this study and according to procedures 
established in this study protocol. Each administration of study product will be documented and 
transferred to the electronic case report form (eCRF). 
6.3 
Assignment to Investigational Product  
At the study site, each screened subject in the RECAST SLE study is assigned a subject 
identifier (SID) during screening that will be used on all subject documentation. Subjects 
enrolled in the SLE OLE study will retain their SID number from the RECAST SLE study. 
No randomization scheme will be used, as all subjects will receive daxdilimab 200 mg Q12W.  
6.4 
Blinding  
This is an open-label study. Subjects and Investigators are aware that the IP is daxdilimab 
200 mg Q12W. 
6.5 
Investigational Product Compliance  
Site staff will administer the IP SC at the study site. The dose and date of administration of IP 
must be recorded in the subject’s medical/study record and eCRF. Treatment compliance will be 
assessed based on this information. 
6.6 
Dose Modification 
Dose adjustment of daxdilimab is not allowed in this study. 
6.7 
Continued Access to Investigational Product After the End of the Study 
After the end of the study, each subject will be treated according to standard clinical practice and 
local practice, at the discretion of the Investigator. 

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6.8 
Treatment of Overdose or Misuse 
Any instance of overdose of IP (suspected or confirmed) must be communicated to the Sponsor 
(Section 8.4.10). Any associated AEs or SAEs must also be reported, and their management 
should be recorded. 
6.9 
Prior and Concomitant Therapy  
Any medication or vaccine (including OTC or prescription medicines, recreational drugs, 
vitamins, and/or herbal supplements) that the subject is receiving at the time of enrollment or 
receives during the study must be recorded along with: 
x Name and indication 
x Reason for use 
x Dates of administration including start and end dates  
x Dosage information including dose and frequency 
Any change to concomitant drugs must also be recorded in the corresponding section of the 
eCRF. 
The Medical Monitor should be contacted if there are any questions regarding concomitant or 
prior therapy. 
6.9.1 
Permitted Concomitant Therapy 
6.9.1.1 
Concomitant Medications and Treatments 
All concomitant medications (from Visit 1) taken while the subject is participating in the study 
will be recorded on the eCRF. Subjects must be instructed not to take any medications, including 
OTC or herbal products or ayurvedic medications without first consulting the Investigator. 
Permitted medications (
) are any medications required per the 
medical history and not specifically prohibited by the protocol during the clinical study (ie, from 
Visit 1 to the end of the SFU period). Any such medications prescribed or used should be 
recorded in the eCRF. 
6.9.1.2 
Concomitant Medications for Systemic Lupus Erythematosus Standard of Care 
During the Study 
Concomitant standard-of-care medications used during the study are part of the subject’s 
previous SLE treatment and, thus, will not be provided by the Sponsor. 
6.9.1.2.1 
Immunosuppressants  
These medications, if given during the RECAST SLE study, must remain stable during the 
treatment period except for oral glucocorticoid (OGC) and nonsteroidal anti-inflammatory drugs 
(NSAIDs), which can be adjusted as long as doses are consistent with the parameters as indicated 
in Sections 6.9.1.2.2 and 6.9.1.2.3, respectively. Background therapy may only be changed for 
documented safety issues. The toxicity/event must be confirmed as a documented AE. The dose 
can be returned to the OLE baseline (Day 1) level if the toxicity/event resolves and if clinically 
indicated. Initiation of any new immunosuppressant or immunomodulator therapy or increase in 

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dose above the level used on Day 1 of the OLE may result in withdrawal of the subject from the 
IP (per Sponsor’s Medical Monitor discretion). 
6.9.1.2.2 
Glucocorticoids  
Oral GCs are permitted but not required for participation in the study. Oral GCs other than 
prednisone may be used orally (PO) at equivalent doses (refer to Appendix 7, Section 10.7). It is 
strongly encouraged that Investigators taper the OGC dose as much as tolerated after a subject 
enrolls into the study, as a goal of this OLE is to determine the lowest clinically appropriate level 
of steroids, including steroid discontinuation, by Week 36 that can be provided while 
maintaining responses. Guidance for taper and bursts is outlined below. During the study, 
Investigators may reach out to discuss any taper or burst scenario with the Medical Monitor as 
needed. 
Oral Glucocorticoid Tapering Guidance  
Oral GC tapering must be started by Week 4 of the clinical study. 
An example of a suggested OGC tapering regimen is provided in Appendix 8, Section 10.8 as 
guidance for Investigators. However, due to variability in subject responses to OGC treatment 
and tolerability of taper, Investigators will have flexibility in how the OGC dose is reduced at 
each visit, however, it is encouraged that Investigators taper each month by at least 1 mg/day. 
OGC tapering must be attempted unless at least one of the following criteria are met: 
1. There are new or worsening organ system(s) affected by SLE. 
2. There is an increase in skin involvement. 
3. There is new or worsening joint involvement. 
If there are scenarios outside these listed criteria in which the Investigator deems tapering not 
appropriate, then the Medical Monitor must be notified and the reason for not tapering will be 
discussed. All reasons for not tapering must be well documented within the EDC. 
Glucocorticoid Burst Guidance 
We encourage Investigators to limit the use of GC bursts throughout the clinical study as 
clinically feasible. GC bursts are allowed at the Investigators discretion. The reason for a GC 
burst and regimen prescribed must be well documented in the EDC. 
Increase in Oral Glucocorticoids for Surgery and Prevention of Adrenal Insufficiency 
Increases in OGCs for surgery and prevention of adrenal insufficiency are allowed as clinically 
indicated. 
6.9.1.2.3 
Other Permitted Medications  
For all enrolled subjects, additional treatments given to subjects with SLE are permitted during 
the study as follows: 
x Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers:  
 If used during the RECAST SLE study, it is recommended that they be maintained at 
a stable dose during the OLE study, unless dose change, discontinuation, or initiation 
is required for documented safety reasons. 

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x Anti-COVID therapeutic antibodies 
 If used during the study, the Medical Monitor must be notified immediately, and 
continuation of IP will be determined on a case-by-case basis. 
x Aspirin  
 Low-dose aspirin (ʿ 350 mg/day) may be used for cardiovascular prophylaxis; this is 
permitted in addition to use of NSAID as specified below. 
x Osteoporosis prophylaxis and treatment  
 Vitamin D and calcium supplementation, and if necessary, treatment of osteoporosis 
is allowed according to local standard-of-care guidelines. These medications will not 
be supplied by the Sponsor. 
x Herbal supplements  
 May be continued during the study. It is strongly recommended that the dosages and 
preparations remain stable unless discontinued all together. It is recommended that no 
herbal supplements be initiated or reinitiated once discontinued during the study. 
x Medications for the treatment of injection site reactions:  
 These are allowed and may include topical or systemic antihistamines, topical GCs, 
paracetamol, or NSAIDs. 
x NSAIDs 
 NSAIDs can be used as needed (PRN) during the OLE (not exceeding local 
guidelines). 
 Subjects taking a NSAID (including cyclooxygenase 2 inhibitors; topical, 
prescription, or OTC) on a regular schedule for SLE symptoms at the OLE baseline 
(Day 1) can continue to do so throughout the study at a stable dose. 
 NSAIDs should not be taken on visit days until all assessments are complete. Subjects 
may have the dose adjusted during the study for documented toxicity/safety reasons. 
 Any NSAIDs (whether prescription, OTC, or topical) should not be used above the 
maximum allowable doses per local guidelines, and site should perform regular AE 
monitoring of these concomitant medications.  
x Opioids  
 Up to 40 mg/day morphine-equivalent are permitted at a stable dose if present at the 
OLE baseline (Day 1). Initiation of opioids and/or PRN dosing of opioids after Day 1 
of the OLE for SLE is discouraged and should not exceed 40 mg/day or equivalent if 
prescribed. These may be titrated off as tolerated during the study. Analgesics, 
including opiates, may be used at stable doses or PRN for temporary relief of 
symptoms not due to SLE, but then are strongly recommended to be avoided 24 hours 
prior to each study visit. 
x Acetaminophen (paracetamol)  

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 Short acting acetaminophen (paracetamol) may be initiated or continued for pain 
control during the study at approved doses. Pain medications should not be used 
within a minimum of 6 to 12 hours (based on known duration of effect) of a 
scheduled visit. 
x Topical therapy for CLE  
 Concurrent use of topical therapy for CLE (eg, GCs, pimecrolimus) is permitted. 
Topical therapy must be the same being used in the 2 weeks prior to the OLE baseline 
(Day 1), and the dose and frequency of application must be stable. During the study, 
topical therapy may be reduced or discontinued based on clinical manifestations and 
Investigator discretion. Should cutaneous skin manifestations reoccur, the same 
topical therapy may be resumed up to the dose used at the OLE baseline (Day 1). 
New dermatologic preparations may be used for the duration of the study if needed. It 
is also recommended that subjects use sunscreen (list as concomitant medication for 
SLE) and avoid sun exposure during the study. Topical moisturizers are also 
permitted. 
Any medications (other than those prohibited by the protocol) that are considered necessary for 
the subjects’ welfare and will not interfere with the study medication may be given at the 
Investigator’s discretion. 
6.9.2 
Prohibited Concomitant Medications 
The treatments and therapies listed in Section 6.9.3 will not be permitted from Day 1 of the OLE 
until the end of the study (with exceptions as noted for those therapies that are potentially 
permitted per Section 6.9.1).  
6.9.3 
Medications and Therapies That Lead to Immediate Discontinuation of 
Investigational Product 
The following therapies are prohibited from Day 1 of the OLE through end of the study. These 
medications are also excluded as per the inclusion and exclusion criteria (Section 5) and during 
the study: 
x Biologic immunomodulators (including but not limited to belimumab, abatacept, or 
rituximab)  
x Bone marrow, stem cell (eg, mesenchymal stem cells), or solid organ transplant 
x Cyclophosphamide 
x GCs 
 Intralesional  
 Intradermal for alopecia 
 Adrenocorticotropic hormone (ACTH) analogs (eg, Acthar®, Synacthen®) 
 dehydroepiandrosterone 
 Topical use (may be allowed per the permitted medications; see Section 6.9.1.2.3) if 
they are used in accordance with inclusion and exclusion criteria (Section 5).  
x Ig therapy (for anti-COVID therapeutic antibodies, see Section 6.9.1.2.3). 
x Investigational agents 

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x IPP-201101 (Lupuzor™) 
x IV corticosteroids > 1 g methylprednisolone or equivalent 
x Janus kinase inhibitors (eg, tofacitinib [Xeljanz®], baricitinib [Olumiant®], upadacitinib 
[Rinvoq™], filgotinib, peficitinib) 
x Live or attenuated vaccines, including Bacille-Calmette-Guerin (the Sponsor 
recommends that Investigators ensure all subjects are up to date with required 
vaccinations prior to entry into the study) 
x Minocycline 
x Plasmapheresis, plasma exchange, or Therakos® photopheresis 
x Thalidomide and thalidomide derivatives (eg, lenalidomide [Thalomid®, Revlimid®]) 
x Topical calcineurin or mammalian target of rapamycin (mTOR) inhibitors (eg, 
pimecrolimus [eg, Elidel®], sirolimus) 
x Sulfasalazine 
x Systemic mTOR inhibitors (eg, sirolimus [Rapamune®]) 
6.9.4 
Restricted Medications 
As daxdilimab is an investigative immunomodulatory agent, non-protocol–permitted changes to 
immune modifiers or immunosuppressants on study are strongly discouraged. 
If a subject starts any of the following during the treatment period or increases the dose above 
the OLE baseline (Day 1) dose, the Investigator must notify the Sponsor’s Medical Monitor 
immediately. The Medical Monitor will determine if the subject may continue to receive IP. 
x Antimalarials:  
 Chloroquine  
 Hydroxychloroquine  
 Quinacrine  
x AZA 
x Cyclosporine  
 Cyclosporine eye drops are permitted for use while on study. 
 Lifitegrast ophthalmic solution (Xiidra eye drops) are permitted for use while on 
study. 
x Danazol 
x Dapsone 
x GCs 
 Intramuscular > 80 mg/day methylprednisolone or equivalent. 
 Intra-articular/tendon sheath/bursal injections of total methylprednisolone > 80 mg or 
equivalent. 
 IV > 40 mg/day but ≤ 1 g/day methylprednisolone or equivalent. 
 OGC  
o > 40 mg/day prednisone or equivalent. 
o Treatment above the OLE baseline (Day 1) dose for a dosing period of > 14 days. 
 Long biologic half-life (eg, dexamethasone, betamethasone). 

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 SC or intramuscular precursors (eg, ACTH). 
x Intra-articular medications other than GCs 
x Leflunomide 
x 6-Mecaptopurine (6-MP) 
x MPA 
x MMF 
x MTX or any change in the route of administration of PO, SC, or intramuscular MTX 
x Sulfasalazine 
x Tacrolimus 
x Voclosporin 
7 
DISCONTINUATION OF INVESTIGATIONAL PRODUCT AND 
SUBJECT DISCONTINUATION/WITHDRAWAL 
Discontinuation of specific sites or of the study as a whole are detailed in Appendix 1, 
Section 10.1.12. 
7.1 
Discontinuation of Investigational Product  
An individual subject will not receive any further IP if any of the following occur in the subject: 
x Receipt of any medications or therapies in Section 6.9.3. 
x A Grade 3 or higher allergic reaction to the IP. 
x A Grade 3 or higher infection considered related to the IP. 
x Other AE that contraindicates further dosing in the opinion of the Investigator and/or the 
Sponsor, Medical Monitor, and/or the SDMC. 
x Withdrawal of consent from further treatment with IP. 
x Subject is determined to have met one or more of the exclusion criteria or failed to meet 
all the inclusion criteria for study participation and there is a potential safety risk 
associated with continuation identified upon consultation with the Medical Monitor. 
x Pregnancy or a decision to become pregnant. 
x Any of the following liver function abnormalities: 
 Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) ≥ 8× upper 
limit of normal (ULN). 
 ALT or AST ≥ 5 × ULN for more than 2 weeks. 
 ALT or AST ≥ 3 × ULN and total bilirubin ≥ 2 × ULN or international normalized 
ratio ≥ 1.5 without alternative explanation. 
 ALT or AST ≥ 3× ULN with the appearance of fatigue, nausea, vomiting, right upper 
quadrant pain or tenderness, fever, rash, and/or eosinophilia (≥ 5%). 

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Subjects who permanently discontinue IP at any point but who do not withdraw consent of study 
participation will complete the Study Week 48/ET visit as soon as possible after IP 
discontinuation and then enter SFU period unless the subject withdraws consent of study 
participation (as described in Section 7.2) or the subject is lost to follow-up (Section 7.3). 
Appendix 4, Section 10.4 describes the process to be followed to identify and appropriately 
report potential Hy’s Law cases and Hy’s Law cases. 
Follow the SoA (Table 1) for data to be collected at the time of discontinuation of IP and follow-
up and for any further evaluations that need to be completed. 
7.2 
Subject Discontinuation/Withdrawal from the Study  
Subjects are free at any time to withdraw from the study (IP and assessments) for any reason, 
without prejudice to further treatment (withdrawal of consent). Such subjects will always be 
asked about the reason(s) for withdrawal and the presence of any AEs. Adverse events will be 
followed-up. If a participant withdraws participation in the study, then no further study visits or 
data collection should take place. 
Subjects who permanently discontinue IP at any point in the study but who do not withdraw 
consent of study participation will complete the Study Week 48/ET visit as soon as possible after 
IP discontinuation and then enter SFU period. Subjects who permanently discontinue IP at any 
point in the study and withdraw consent of study participation will only complete the 
Week 48/ET assessments (if they agree to do so before withdrawing consent). Subjects will not 
be automatically removed from the study if any administration of IP is missed. 
Further details concerning use of samples collected during the study from a subject that 
withdraws consent are provided in Appendix 1, Section 10.1.7. 
7.3 
Lost to Follow-up  
A subject will be considered lost to follow-up if the subject repeatedly fails to return for 
scheduled visits and is unable to be contacted by the study site. 
Subjects will be considered lost to follow-up only if no contact has been established by the time 
the study is completed such that there is insufficient information to determine the participant’s 
status on Day 393 (Visit 15). 
The following actions must be taken if a subject fails to return to the clinic for a required study 
visit: 
x The site must attempt to contact the subject and reschedule the missed visit as soon as 
possible, counsel the subject on the importance of maintaining the assigned visit schedule 
and ascertain whether the subject wishes to and/or should continue in the study. 
x Before a subject is deemed lost to follow-up, the Investigator or designee must make 
every effort to regain contact with the subject with 3 documented attempts at contact (with 
one documented attempt being a registered letter/certified mail): 
 Registered letter/certified mail 
 Phone calls, text messages, or emails 
 Consulting publicly available sources, if allowed by local regulations, to determine 
the status of the subject. 

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These contact attempts should be documented in the subject’s medical record. 
x Should the subject continue to be unreachable, the subject will be considered to have 
withdrawn from the study. 
“Lost to follow-up” as a reason for study discontinuation must be documented by time and date 
of telephone calls, emails, text messages, numbers called, individuals spoken to if not the 
subject, documentation that a certified/registered letter was sent, and documentation of publicly 
available sources that were consulted. 
8 
STUDY ASSESSMENTS AND PROCEDURES 
Study procedures and their timing are summarized in the SoA (Table 1).  
Adherence to the study design requirements, including those specified in the SoA, is essential 
and required for study conduct. 
Thorough review of eligibility requirements must be completed by the Investigator to confirm 
that potential subjects meet all eligibility criteria. The Investigator will maintain a screening log 
to record details of all subjects screened and to confirm eligibility or record reasons for screening 
failure, as applicable. 
In the event of a significant study-continuity issue (eg, caused by a pandemic), alternate 
strategies for subject visits, assessments, medication distribution, and monitoring may be 
implemented by the Sponsor or the Investigator, as per local health authority/ethics requirements. 
Repeat or unscheduled samples may be taken for safety reasons or for technical issues with the 
samples. 
8.1 
Administrative and General Procedures 
Once a subject has completed the treatment period (through Week 48) of the RECAST SLE 
study, signed the ICF, and met all study eligibility criteria, he/she may be enrolled in this OLE 
study. Informed consent must be obtained by the Principal Investigator (PI) or a designee such as 
an appropriately qualified sub-Investigator at the beginning of the study visit. The informed 
consent process should be documented. 
Subjects who complete the treatment period (through Week 48) of the RECAST SLE study and 
wish to enroll in the OLE study will undergo a review of eligibility requirements and enrollment 
on Day 1, a treatment and assessment period of 48 weeks, and a SFU period of 8 weeks (through 
Week 56) as indicated in the SoA (Table 1). 
A laboratory manual will be provided to the study sites that specifies the procedures for 
collection, processing, storage, and shipment of samples, as well as laboratory contact 
information, specific to this clinical research study. 
Treatment Period 
To allow for the continuous dosing of the subjects, the start of this OLE study should occur 
immediately after the completion of the RECAST SLE treatment period (ie, first OLE dosing 
[Day 1] coinciding with Week 48/Visit 14 of the RECAST SLE study). Any exceptions to this 
enrollment date must be reviewed and approved by the Medical Monitor before any subject is 
allowed to enroll after the Week 48/Visit 14 of the RECAST SLE study. 

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On Day 1 (Visit 1), all assessments are to be performed prior to IP treatment; any procedure that 
was also completed for RECAST SLE Visit 14 (if performed on the same day as Visit 1 for this 
study) should be used for this study and not repeated. 
On dosing days, all assessments are to be performed prior to IP treatment unless noted otherwise. 
Telehealth Visits 
Telehealth visits will be performed at Weeks 4, 8, 16, 20, 28, 32, 40, and 44 of the treatment 
period. Telephone or video calls may be utilized. Telehealth visits should be performed by a 
qualified healthcare provider. These telehealth visits will be used to assess the subject’s current 
disease status, OGC tapering schedule and assess safety and concomitant medications. If there is 
any situation (including, but not limited to worsening of SLE symptoms or potential change in 
the expected steroid taper) that in the opinion of the Investigator requires evaluation, an in-clinic 
unscheduled visit should be arranged and all relevant assessments should be performed. 
Early Termination/Follow-up Visits 
The Week 48 visit (Visit 13) is the end-of-treatment visit for subjects who complete the 
treatment period. After the treatment period (Week 0 to Week 48), the subjects will enter an 
8-week safety follow-up period (Week 48 to Week 56), which consists of 2 study-site visits 
(Week 52 and Week 56). 
Subjects who discontinue IP early will follow the procedures for early discontinuation of IP 
(Section 7.1).  
The full list of procedures and timing of assessments to be performed during the ET and SFU 
visits are provided in the SoA (Table 1). 
Unscheduled Visits 
An unscheduled visit should be performed if a subject complains of worsening SLE symptoms, if 
a subject use OGCs outside of study-permitted doses, if a blood test/evaluation needs to be 
repeated, if an AE needs to be evaluated, or any situation, which in the opinion of the 
Investigator, requires an evaluation. Clinically indicated relevant and necessary assessments 
should be performed during unscheduled visits, including assessment of concomitant 
medications and AEs, as appropriate. 
8.2 
Exploratory Efficacy Assessments  
Planned time points for all exploratory efficacy assessments are provided in the SoA (Table 1). 
8.2.1 
Training Provision and Requirements  
The Sponsor or designee will provide necessary training to instruct the Investigators, study 
coordinators, and other applicable site staff to ensure appropriate study conduct. This training 
will include information on the protocol, study procedures including completion of the lupus 
assessments, the completion of the case report forms (CRFs), and other identified training topics. 
Training will include printed training materials, online videos, and formal presentations, as well 
as web-based training modules. Required trainings will be documented in the site training plan. 
All assessments and certifications must be renewed prior to expiration. If there is a change in site 
personnel over the course of the study, new Investigators or physicians must complete all the 

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required training prior to performing study procedures. Documentation of completed training 
will be filed in the Investigator site file and the trial master file. 

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8.2.7 
Oral Glucocorticoid Reduction  
Refer to Section 6.9.1.2.2 for all information regarding OGC tapering. 

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8.3 
Safety Assessments 
Planned time points for all safety assessments are provided in the SoA (Table 1) and are 
described below. 
8.3.1 
Physical Examinations 
A full physical examination will be performed at the Week 0 [Day 1] and Week 48 visits. A 
focused physical examination should be performed at all other visits. A focused physical 
examination should always include assessment of head, ears, eyes, nose, throat, lungs, heart, 
abdomen, skin, and extremities. 
Medically significant changes from the screening physical examination will be recorded as AEs, 
unless they are considered a manifestation of SLE and 
. 
8.3.2 
Vital Signs 
Vital signs, blood pressure (mmHg), pulse rate (beats/min), respiratory rate (breaths/min), and 
body temperature (ºC), and body weight (kg) will be obtained as outlined in Table 1 using 
clinically acceptable methods and devices as defined in the SoA. Vital signs should be measured 
in a seated position having rested in this position for at least 5 minutes before each reading and, 
when possible, should be taken before any blood draws. Prior to and after IP administration, vital 
signs should be checked as follows:  
x Within 15 minutes prior to administration of IP but within 30 minutes on days when an 
ECG is to be performed. 
x Every 30 minutes (± 5 minutes) for 60 minutes after administration or until stable, 
whichever is later (for the first 2 study visits only). 
If anaphylaxis or a hypersensitivity reaction occurs after the SC administration of IP, vital signs 
will be taken more frequently, based on Investigator’s judgment and as warranted by the severity 
of the reaction (Appendix 5, Section 10.5) 
8.3.3 
Electrocardiograms 
A computerized 12-lead ECG will be performed at the visits specified in the SoA (Table 1). The 
Investigator or a qualified designee will review and indicate if the ECG is normal, abnormal but 
not clinically significant, or abnormal and potentially clinically significant. 
The ECG should be performed after vital signs are examined and after 10 minutes at rest in a 
supine position. 

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8.3.4 
Local Injection Tolerability Assessments 
Daxdilimab will be administered by study-site staff in the clinic, and each subject will be 
assessed for local injection tolerability 60 minutes after the first and second doses (Day 1 and 
Week 12) are administered. The Investigator, or designee, will evaluate the injection sites at 
these visits, and will document the presence or absence of local intolerance/injection site 
reactions and will open an AE in case of local injection site intolerance. Additional local 
injection tolerability assessments will be conducted at additional time points as specified in the 
SoA (Table 1). Additional follow-up after Week 48 can be performed for any ongoing injection 
site reactions. 
8.3.5 
Clinical Safety Laboratory Tests  
All protocol-required laboratory tests, as defined in Table 4, must be conducted in accordance 
with the laboratory manual and at a central laboratory at the visits specified in the SoA (Table 1). 
The Investigator must review and sign the laboratory results, document this review, and record 
any clinically significant changes occurring during the study as an AE if applicable (see 
Section 8.4.2). The laboratory results must be retained with source documents. 
Abnormal laboratory findings associated with the underlying disease are not considered 
clinically significant unless judged by the Investigator to be more severe than expected for the 
subject’s condition. 
All laboratory tests with values considered clinically significantly abnormal during participation 
in the study should be repeated as soon as possible (preferably within 24 to 48 hours) until the 
values return to normal or baseline or are no longer considered clinically significant by the 
Investigator or Medical Monitor. 
Urgent safety labs should be performed at the central laboratory, if possible. If urgent results are 
needed, testing can be sent to a local laboratory, but blood for the same tests should be obtained 
at the same time for central laboratory analysis, if possible. 
Additional safety samples may be collected as clinically indicated at the discretion of the 
Investigator or as required by local regulations. 
Every attempt should be made to redraw any missing safety laboratory tests, even if the subject 
has received the IP. 
The laboratory results should be signed and dated and retained at the site as source data for 
laboratory variables. 

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Table 4 
Clinical Laboratory Tests  
Immunology 
 
ANA 
Anti- dsDNA 
Anti-Smith 
Anti-RNP 
Anti-SSA 
Anti-SSB 
C3 and C4 
Rheumatoid factor 
Hematology and coagulation 
Hemoglobin 
Hematocrit 
Mean corpuscular hemoglobin concentration 
Mean corpuscular volume 
Platelet count 
PT/INR and PTT 
RBC count 
Reticulocyte count 
WBC with differential 
Pregnancy tests 
Urine dipstick β-hCG 
FSH a 
Other laboratory tests 
HbA1c 
Hs-CRP 
Lipids (TC, TG, HDL-C, and LDL-C) 
pDC  
Serum IgG, IgA, and IgM 
 
Serum chemistry 
Albumin 
ALT 
ALP 
AST 
Bicarbonate 
Blood urea nitrogen 
Calcium 
Chloride 
Creatine kinase 
Creatinine 
eGFR 
GGT 
Glucose 
Potassium 
Sodium 
Total bilirubin 
Total protein 
Serum virology 
HBcAb (reflex DNA testing if isolated hepatitis B core positive) 
Urinalysis 
Dipstick 
Appearance 
Bilirubin 
Blood 
Color 
Epithelial cells 
Glucose 
Ketones 
Leukocyte esterase 
pH 
Protein 
Specific gravity 
Microscopy, including WBC/HPF, RBC/HPF, and casts 
Urine creatinine and protein; spot UPCr 
ALP = alkaline phosphatase; ALT = alanine aminotransferase; ANA = antinuclear antibodies; AST = aspartate 
aminotransferase; β-hCG = beta-human chorionic gonadotropin; C = complement; dsDNA = double-stranded 
DNA; eGFR = estimated glomerular filtration rate; FSH = follicle-stimulating hormone; GGT = gamma 
glutamyl transferase; HbA1c = glycosylated hemoglobin; HBcAb = hepatitis B core antibody; HDL-C = high-
density lipoprotein-cholesterol; HIV = human immunodeficiency virus; HPF = high-power field; hs-

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Table 4 
Clinical Laboratory Tests  
CRP = high-sensitivity C-reactive protein; Ig = immunoglobulin; INR = international normalized ratio; 
LDL-C = low-density lipoprotein-cholesterol; pDC = plasmacytoid dendritic cell; PT = prothrombin time; 
PTT = partial thromboplastin time; RBC = red blood cell; RNP = ribonucleoprotein; SSA = Sjögren’s 
syndrome-related antibody A; SSB = Sjögren’s syndrome-related antibody B; TC = total cholesterol; 
TG = triglycerides; UPCr = urine protein:creatinine ratio; WBC = white blood cell  
a 
See Section 5.1 (inclusion criterion 3) for procedures to be followed if a female subject becomes 
postmenopausal during the study. 
8.3.5.1 
Hepatitis B Assessments 
Hepatitis B DNA testing (Reflex DNA testing) will continue to be performed Q12W if the 
subject had an isolated hepatitis B core positive result in the RECAST SLE study. The IP will be 
discontinued if the subject’s hepatitis B virus DNA levels are confirmed to exceed the lower 
limit of quantitation as per the central laboratory. 
8.3.6 
Pregnancy Testing  
Urine pregnancy tests will be performed in women of childbearing potential during treatment 
and follow-up at the study site using a dipstick, as indicated in the SoA (Table 1). See 
Section 5.1 (inclusion criterion 3) for procedures to be followed if a female subject becomes 
postmenopausal during the study.  
8.4 
Adverse Events, Serious Adverse Events, and Other Safety Reporting 
An external, independent SDMC will perform evaluations of safety data at specified regular 
intervals throughout the study and make recommendations to the Sponsor regarding further 
conduct of the study. See Section 10.1.5 for details on SDMC activities. 
8.4.1 
Definitions 
x Adverse event: An AE is any untoward medical occurrence in a subject administered a 
pharmaceutical product and that does not necessarily have a causal relationship with this 
treatment. An AE can therefore be any unfavorable and unintended sign (including an 
abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally 
associated with the use of an IP, whether or not considered related to the IP. Events that 
meet and do not meet the AE definition are provided in Appendix 2, Section 10.2.1. 
x Serious adverse event: An event is considered “serious” if, in the view of either the 
Investigator or Sponsor, it results in any of the following outcomes:  
 Death 
 A life-threatening AE (An event is considered ɋlife-threateningɌ if, in the view of 
either the Investigator or Sponsor, its occurrence places the subject(s) 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.) 
 Inpatient hospitalization or prolongation of existing hospitalization 
 A persistent or significant incapacity or substantial disruption of the ability to conduct 
normal life functions 
 A congenital anomaly/birth defect 

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 Important medical events that may not result in death, be life-threatening, or require 
hospitalization may be considered serious when, based upon appropriate medical 
judgment, they may jeopardize the subject(s) or may require medical or surgical 
intervention to prevent one of the outcomes listed in this definition. 
Additional information is provided in Appendix 2, Section 10.2.2. 
x Adverse reaction: An adverse reaction is any AE caused by a drug. 
x Adverse event of special interest: An AESI is an AE of scientific and medical interest 
specific to understanding of the IP and may require close monitoring and collection of 
additional information by the Investigator. An AESI may be serious or nonserious. The 
rapid reporting of AESIs allows ongoing surveillance of these events in order to 
characterize and understand them in association with the use of this IP. 
The following AESIs will be particularly monitored in this study:  
 Hypersensitivity reaction, including anaphylaxis 
 Severe (Grade 3 or higher) viral infections/reactivations 
 Opportunistic infection as listed in Appendix 6, Section 10.6 (all cases) 
 Malignancy (except nonmelanoma skin cancer) 
8.4.2 
Adverse Event Reporting 
The Investigator and any qualified designees are responsible for detecting, documenting, and 
recording events that meet the definition of an AE or SAE and remain responsible for following 
up all AEs. This includes events reported by the subject (or, when appropriate, by a caregiver, 
surrogate, or the subject’s legally authorized representative). 
Report initiation for all AEs and SAEs will begin from the time of signing ICF and continue up 
until the final study visit. All events will be followed to resolution or until they are considered as 
a non-clinically significant event. 
Adverse events reported by the subject, spontaneously or in response to an open question from 
the study personnel, and AEs revealed by observation will be recorded during the study at the 
investigational site.  
Clinically significant abnormalities in vital signs, body weight, physical examination, laboratory 
parameters, and ECGs will be recorded as separate AEs or SAEs if they are not considered as 
part of pre-existing medical conditions or have already been recorded due to other AEs or SAEs. 
Worsening or new manifestations of SLE (eg, 
 do not 
have to be reported as AEs, unless they meet the criteria for a SAE. All AEs meeting criteria 
must be reported immediately. 
For each AE, the Investigator will evaluate and report the onset (date and time), resolution (date 
and time), severity, causality, action taken, serious outcome (if applicable), and whether it caused 
the subject to discontinue the study. The AE term should be reported in standard medical 
terminology when possible. 
Additional information is provided in Appendix 2, Section 10.2.3. 

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8.4.3 
Classification of an Adverse Event 
8.4.3.1 
Causality or Relatedness 
The Investigator is required to provide an assessment of the relationship of AEs and SAEs to the 
IP. The Investigator will use clinical judgment to determine the relationship.  
An event will be considered “not related” to use of IP if any of the following are met: 
x An unreasonable temporal relationship between administration of the IP and the onset of 
the event (eg, the event occurred either before, or too long after, administration of the IP 
for it to be considered IP related). 
x A causal relationship between the IP and the event is biologically implausible (eg, death 
as a passenger in an automobile accident). 
x A clearly more likely alternative explanation for the event is present (eg, typical adverse 
reaction to a concomitant drug and/or typical disease-related event). 
Individual AE/SAE reports will be considered “related” to use of the IP if the “not related” 
criteria are not met. 
“Related” implies that the event is considered to be “associated with the use of the drug” 
meaning that there is “a reasonable possibility” that the event may have been caused by the IP 
(ie, there are facts, evidence, or arguments to suggest possible causation). 
Alternative causes, such as underlying disease(s), concomitant therapy, and other risk factors, as 
well as the temporal relationship of the event to IP administration, will be considered and 
investigated. 
For causality assessment, the Investigator will also consult the IB. 
The Investigator must review and provide an assessment of causality for each AE/SAE and 
document this in the medical notes. There may be situations in which an SAE has occurred, and 
the Investigator has minimal information to include in the initial report to the Sponsor. However, 
it is very important that the Investigator always make an assessment of causality for every event 
before the initial transmission of the SAE data to the Sponsor. 
The Investigator may change their opinion of causality in light of follow-up information and 
send an SAE follow-up report with the updated causality assessment. 
The causality assessment is one of the criteria used when determining regulatory reporting 
requirements. 
8.4.3.2 
Severity or Intensity 
The guidelines outlined in Common Terminology for Adverse Events (CTCAE) v5.0 will be 
used for assessing the severity or intensity of the event. The general guidelines for assessing the 
AE grade are provided in Table 5. 

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Table 5 
CTCAE v5.0 General Guidelines 
Grade 
Description 
Grade 1 
Mild; asymptomatic or mild symptoms; clinical or diagnostic observations only; intervention not 
indicated. 
Grade 2 
Moderate; minimal, local, or noninvasive intervention indicated; limiting age-appropriate 
instrumental ADL a.  
Grade 3 
Severe or medically significant but not immediately life-threatening; hospitalization or 
prolongation of hospitalization indicated; disabling; limiting self-care ADL b. 
Grade 4 
Life-threatening consequences, urgent intervention indicated. 
Grade 5 
Death related to AE. 
ADL = activities of daily living; AE = adverse event; CTCAE = Common Terminology for Adverse Events. 
The CTCAE v5.0 is dated to 27 NOV 2017. 
a 
Instrumental ADL refers to preparing meals, shopping for groceries or clothes, using the telephone, managing 
money, etc. 
b 
Self-care ADL refers to bathing, dressing, and undressing, feeding self, using the toilet, taking medications, 
and not bedridden. 
8.4.4 
Time Period and Frequency for Collecting AE and SAE Information 
All AEs and SAE reporting will begin from the time of signing ICF and continue up until the 
final study visit at the time points specified in the SoA (Table 1). All events will be followed to 
resolution or until they are considered a non-clinically significant event. 
Investigators are not obligated to actively seek information on AEs or SAEs after conclusion of 
the study participation. However, if the Investigator learns of any SAE, including a death, at any 
time after a subject has been discharged from the study, and the Investigator considers the event 
to be reasonably related to the IP or study participation, the Investigator must promptly notify the 
Sponsor. 
8.4.5 
Method of Detecting AEs and SAEs 
Care will be taken not to introduce bias when detecting AEs and/or SAEs. Open-ended and 
nonleading verbal questioning of the subject is the preferred method to inquire about AE 
occurrences. 
8.4.6 
Follow-up of AEs and SAEs 
The Investigator is responsible for appropriate medical care of subjects during the study. After 
the initial AE/SAE report, the Investigator is required to proactively follow each subject at 
subsequent visits/contacts. All events will be followed to resolution or until they are considered a 
non-clinically significant event, or the event is otherwise explained, or the participant is lost to 
follow-up (as defined in Section 7.3). 
Additional information regarding follow-up procedures is provided in Appendix 2, 
Section 10.2.3. 
8.4.7 
Regulatory Reporting Requirements for SAEs  
Any death, life-threatening event, or other SAE and any pregnancy, overdose, and AESI 
experienced by a subject during the course of the study, whether or not judged related to the 

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investigational product, must be reported within 24 hours of knowledge of the event by entering 
the information into the eCRF. If unable to access the eCRF, the event must be reported by 
submitting the completed SAE form via email or fax to the contact numbers provided below. 
x Email: clinicalsafety@horizontherapeutics.com 
x Fax: (800) 860-7836 
The event must be documented in source documentation and the eCRF. The following steps will 
be taken to report promptly and document accurately any SAE, whether or not it appears to be 
related to IP: 
1. Report the SAE to the Sponsor by entering the information into the eCRF within 24 hours 
after becoming aware that a subject has experienced an SAE. If unable to access the 
eCRF, the event must be reported by submitting the completed SAE form by email to 
clinicalsafety@horizontherapeutics.com or fax within 24 hours after becoming aware that 
a subject has experienced an SAE. 
2. Perform appropriate diagnostic tests and therapeutic measures, and submit all follow-up 
substantiating data, such as diagnostic test reports, hospital discharge summaries, and 
autopsy report to the Sponsor’s representative. 
3. Respond in a timely manner to any queries from Sponsor regarding the SAE. 
4. Conduct appropriate consultation and follow-up evaluation until the SAE is resolved, 
stabilized, or otherwise explained by the Investigator. 
5. Review each SAE report and evaluate the relationship of the IP. 
6. Each Investigator must report all AEs or SAEs to its Institutional Review Board (IRB) or 
Independent Ethics Committee (IEC) in accordance with IRB or IEC requirements. 
After receipt of the initial report, the information will be reviewed, and the Investigator may be 
contacted with requests for additional information or for data clarification. 
Follow-up will be obtained via the eCRF, fax, or email, as necessary, until the event resolves or 
attains a stable outcome. Sponsor or designee is responsible for the preparation of MedWatch 
3500 A/Council for International Organizations of Medical Sciences I forms and analysis of 
similar events for individual occurrences (to be submitted as Investigational New Drug [IND] 
safety letters to the FDA and Investigators according to Title 21 of the Code of Federal 
Regulations [21 CFR 312.32] by the Sponsor). 
Additional information regarding SAE reporting via an electronic or paper data collection tool is 
provided in Appendix 2, Section 10.2.4. 
8.4.8 
Pregnancy 
Pregnancy in a woman who has received IP must be reported to the Sponsor from time of signed 
ICF until end-of-study follow-up or 3 months (approximately 5 half-lives) following the last 
dose of IP in case of early withdrawal. The Investigator must report the pregnancy to the Sponsor 
or representative as if it were an SAE (ie, within 24 hours of learning of the pregnancy) Refer to 
Section 8.4.7 for additional information. 
Subjects who become pregnant during the study period must not receive additional doses of IP. 
These subjects will discontinue IP and follow the IP discontinuation procedures (Section 7.1). 
While pregnancy itself is not considered to be an AE or SAE, any pregnancy complication or 
elective termination of a pregnancy for medical reasons will be reported as an AE or SAE. 

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Abnormal pregnancy outcomes (eg, spontaneous abortion, fetal death, stillbirth, congenital 
anomalies, ectopic pregnancy) are considered SAEs and will be reported as such. 
The subject will be followed to determine the outcome of the pregnancy. The Investigator will 
collect follow-up information on the subject and the neonate, and the information will be 
forwarded to the Sponsor after the outcome. 
Should the Investigator become aware of a pregnancy in the partner of a male study subject who 
has received IP, this should be reported to the Sponsor within 24 hours of knowledge of the event 
(refer to Section 8.4.7 for additional information). The Sponsor will endeavor to collect follow-
up information on such pregnancies, provided the partner of the study subject provides consent 
for disclosure of their information. 
Any poststudy pregnancy-related SAE considered reasonably related to the IP by the Investigator 
will be reported to the Sponsor as described in Section 8.4.7. While the Investigator is not 
obligated to actively seek this information in former study subjects or pregnant female partner, 
he or she may learn of an SAE through spontaneous reporting. 
8.4.9 
Adverse Events of Special Interest 
The Investigator must report AESIs to the Sponsor as if it were an SAE (ie, within 24 hours of 
learning of the AESI). Refer to Section 8.4.7 for contact information. 
Definition of an AESI and AESIs that will be monitored in the study are provided in 
Section 8.4.1. 
8.4.10 
Overdose or Misuse 
Any instance of overdose of IP (suspected or confirmed) must be communicated to the Sponsor 
as if it were an SAE (ie, within 24 hours of learning of overdose or misuse). Refer to 
Section 8.4.7 for additional information. Any associated AEs or SAEs must also be reported, and 
their management should be recorded as described in Section 8.4.7.  
8.5 
Pharmacokinetics  
Serum for PK analysis will be collected at the visits specified in Table 1 and analyzed using a 
validated bioanalytical method. 
Samples will be collected, labeled, stored, and shipped as detailed in the laboratory manual. The 
time of PK sample collection must be recorded. 
The timing of sampling may be altered during the course of the study based on newly available 
data (eg, to obtain data closer to the time of peak plasma concentrations) to ensure appropriate 
monitoring.  
Samples will be used to evaluate the PK of daxdilimab. Samples collected for analyses of 
daxdilimab serum concentration may also be used to evaluate safety or efficacy aspects related to 
concerns arising during or after the study. 
Genetic analyses will not be performed on these samples.  

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8.6 
Pharmacodynamics 
Whole blood will be collected for the assessment of pDC levels by flow cytometry at the visits 
specified in the SoA (Table 1). Daxdilimab binds to ILT7 on the surface of pDCs leading to 
recruitment of macrophages and NK cells, thus inducing apoptosis and reduction in the number 
of pDCs.  
Samples will be analyzed using a validated analytical method in compliance with the Sponsor’s 
standard operating procedures and analytical requirements. Instructions for sample collection, 
processing, storage, and shipment are provided in the study-site manual. 
8.7 
Genetics 
Genetics will not be evaluated in this study. 
8.9 
Immunogenicity Assessments  
Serum for immunogenicity ADA analysis will be collected at the visits specified in Table 1 and 
assessed using a validated immunoassay. Additionally, serum samples should also be collected at 
the final visit from subjects who discontinued IP or were withdrawn from the study. These 
samples will be tested by the Sponsor or Sponsor’s designee. 
The ADA samples will be collected at the same time as the PK samples and the time of sample 
collection must be recorded. 
Serum samples will be screened for antibodies binding to daxdilimab and the titer of confirmed 
positive samples will be reported. Other analyses may be performed to further characterize the 
immunogenicity of daxdilimab. 
Antibodies may be further characterized and/or evaluated for their ability to neutralize the 
activity of daxdilimab. Samples may be stored for a maximum of 25 years (or according to local 

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regulations) following the last subject’s last visit for the study at a facility selected by the 
Sponsor to enable further analysis of immune responses to daxdilimab. 
Samples will be collected, labeled, stored, and shipped as detailed in the study-site manual. 
9 
STATISTICAL CONSIDERATIONS 
9.1 
Primary Hypothesis  
No formal statistical hypothesis will be evaluated in the SLE OLE study. 
9.2 
Analysis Sets  
Safety analysis set: The safety analysis set is defined as subjects who received any dose of 
daxdilimab in this OLE study. The safety, PD, immunogenicity, and exploratory efficacy 
analyses will be based on the safety analysis set. 
Pharmacokinetic analysis set: The PK analysis set is defined as subjects who received any dose 
of daxdilimab in this OLE study and have at least one measurable PK concentration post dose. 
The PK analyses will be based on PK analysis set. 

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9.3 
Statistical Analyses 
9.3.1 
General Considerations  
For continuous data, number of observations, mean, standard deviation, median, minimum, and 
maximum will be reported. For categorical data, percent and frequency will be reported. Data 
listings will be sorted by treatment group and subject number. Details of the statistical analysis 
will be specified in a separate SAP. 
9.3.2 
Primary Endpoint(s) Analysis 
9.3.2.1 
Safety Analysis 
Adverse events will be coded using the Medical Dictionary for Regulatory Activities by system 
organ class (SOC) and preferred term (PT). In general, if an AE onset is on or after the first OLE 
dose date, the AE will be considered as a treatment-emergent AE (TEAE) for OLE. All TEAEs 
will be summarized overall and by SOC and PT, as well as by severity and by relationship to 
daxdilimab.  
For the summary of TEAEs by severity, each participant will be counted only once within a SOC 
or a PT by using the AEs with the highest intensity within each category. For the summary of 
TEAEs by relationship to IP, each participant will be counted only once within a SOC or a PT by 
using the AEs with the greatest reported relationship within each category. TEAE leading to 
discontinuation of daxdilimab will be summarized by SOC and PT. Treatment-emergent SAEs 
and treatment-emergent AESIs will also be summarized. 
Clinically significant abnormalities in laboratory parameters, vital signs, ECGs, and physical 
examinations will be recorded as AEs or SAEs. Laboratory assessments, vital signs, and ECGs, 
as well as their changes from baseline at each visit will also be summarized descriptively. 
9.3.3 
Secondary Endpoint(s) Analysis 
9.3.3.1 
Pharmacokinetics Analysis 
The PK analysis will be based on the PK analysis set. Descriptive statistics of the serum 
daxdilimab concentration will be tabulated by visit.  
9.3.3.2 
Immunogenicity Analysis 
Number and percentage of subjects who develop positive ADA will be summarized 
descriptively.  
9.3.3.3 
Pharmacodynamics Analysis  
The observed count along with the change and percent change from baseline in pDCs will be 
summarized descriptively. 
9.3.4 
Exploratory Endpoint(s)Analyses 
The exploratory efficacy analyses will be detailed in the SAP. 

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9.4 
Interim Analysis  
An interim analysis will not be performed. 
9.5 
Sample Size Determination 
Sample size determination is based on the number of subjects who have completed the treatment 
period of Study VIB7734.P2.S1 (RECAST SLE). A total of 195 subjects have been randomized 
in the RECAST SLE study. Assuming that 20% of subjects will prematurely discontinue 
treatment, there will be a total of approximately 156 subjects who will be eligible for this long-
term safety study. 

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10 
SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS 
10.1 
Appendix 1: Regulatory, Ethical, and Study Oversight Considerations 
10.1.1 
Regulatory and Ethical Considerations 
x This study will be conducted in accordance with the protocol and with the following: 
 Consensus ethical principles derived from international guidelines including the 
Declaration of Helsinki and the Council for International Organizations of Medical 
Sciences international ethical guidelines 
 Applicable International Council for Harmonisation (ICH) Good Clinical Practice 
(GCP) guidelines 
 Applicable laws and regulations 
x The protocol, protocol amendments, informed consent form, Investigator’s brochure, and 
other relevant documents (eg, advertisements) must be submitted to an Institutional 
IRB/IEC by the Investigator and reviewed and approved by the IRB/IEC before the study 
is initiated. 
x Any amendments to the protocol will require IRB/IEC approval before implementation of 
changes made to the study design, except for changes necessary to eliminate an 
immediate hazard to study subjects.  
x Protocols and any substantial amendments to the protocol will require health authority 
approval prior to initiation except for changes necessary to eliminate an immediate 
hazard to study subjects. 
x The Investigator will be responsible for the following, as applicable: 
 Providing written summaries of the status of the study to the IRB/IEC annually or 
more frequently in accordance with the requirements, policies, and procedures 
established by the IRB/IEC 
 Notifying the IRB/IEC of SAEs or other significant safety findings as required by 
IRB/IEC procedures 
 Providing oversight of the conduct of the study at the site and adherence to 
requirements of 21 CFR, ICH guidelines, the IRB/IEC, European regulation 536/2014 
for clinical studies, European Medical Device Regulation 2017/745 for clinical device 
research, and all other applicable local regulations 
10.1.2 
Financial Disclosure 
Investigators and sub-Investigators will provide the Sponsor with sufficient, accurate financial 
information as requested to allow the Sponsor to submit complete and accurate financial 
certification or disclosure statements to the appropriate regulatory authorities. Investigators are 
responsible for providing information on financial interests during the course of the study and for 
one year after completion of the study. 

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10.1.3 
Informed Consent Process 
The Investigator or the Investigator’s representative will explain the nature of the study, 
including the risks and benefits, to the potential subject (or their legally authorized 
representative) and answer all questions regarding the study.  
Potential subjects must be informed that their participation is voluntary. They (or their legally 
authorized representatives) will be required to sign a statement of informed consent that meets 
the requirements of 21 CFR 50, local regulations, ICH guidelines, privacy and data protection 
requirements, where applicable, and the IRB/IEC or study site.  
It is the responsibility of the Investigator (or their designee, where allowed by local 
requirements) to obtain written informed consent from all study subjects. The Investigator or 
their designee must provide the Sponsor/designee with a copy of the IRB/IEC-approved 
informed consent document(s) prior to the start of the study at the site. The informed consent 
must allow for access to the records for at least 25 years to allow for possible future inspections.  
The medical record must include a statement that written informed consent was obtained before 
the subject was enrolled in the study and the date the written consent was obtained. The 
authorized person obtaining the informed consent must also sign the ICF. 
Subjects must be reconsented to the most current version of the ICF(s) during their participation 
in the study. 
The original, appropriately signed and dated ICF must be retained by the Investigator/study site 
as part of that subject’s record. A copy of the signed ICF must be given to the subject. 
The ICF must be fully approved by an IRB or an IEC prior to its use with study subjects. 
The Sponsor reserves the right to delay initiation of the study at a site where the informed 
consent document(s) do not meet the standards of this section, applicable regulations, and/or ICH 
E6(R2). 
The ICF will contain a separate section that addresses the use of leftover samples for future 
research. The investigator or authorized designee will explain to each subject the objectives of 
the future research. Subjects will be told that they are free to refuse to participate and may 
withdraw their consent at any time and for any reason during the storage period. A separate 
signature will be required to document a subject’s agreement to allow any leftover samples to be 
used for future research. Subjects who decline to participate in this future research will not 
provide this separate signature. 
10.1.4 
Data Protection and Privacy 
All information generated in this study is considered highly confidential and must not be 
disclosed to any person or entity not directly involved with the study unless prior written consent 
is obtained from the Sponsor. The subject must be informed that their medical records may be 
examined by Clinical Quality Assurance auditors or other authorized personnel appointed by the 
Sponsor, by appropriate IRB/IEC members, and by inspectors from regulatory authorities. 
Subjects will be assigned a unique identifier by the Sponsor. Any subject records or datasets that 
are transferred to the Sponsor will contain the identifier only; subject names or any information 
which would make the subject identifiable will not be transferred. 

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The subject must be informed that their personal study-related data will be used by the Sponsor 
in accordance with local data protection law. The level of disclosure must also be explained to 
the subject who will be required to give consent for their data to be used as described in the 
informed consent  
The contract between Sponsor and study sites specifies responsibilities of the parties related data 
protection, including handling of data security breaches and respective communication and 
cooperation of the parties. 
Information technology systems used to collect, process, and store study-related data are secured 
by technical and organizational security measures designed to protect such data against 
accidental or unlawful loss, alteration, or unauthorized disclosure or access. 
10.1.5 
Committees Structure 
10.1.5.1 
Safety Data Monitoring Committee 
The external, independent Safety Data Monitoring Committee (SDMC) is responsible for 
safeguarding the interests of study subjects via review of accumulating safety data and for 
supporting study integrity and interpretability based on their review of ongoing study conduct. 
The SDMC will provide the Sponsor with recommendations for actions with respect to study 
conduct and the management of subjects treated under the study protocol. The SDMC members 
are independent of the Sponsor and any CRO/organization collaborating with the Sponsor on the 
study.  
The SDMC will not be charged with any formal interim analysis, will not conduct a futility 
analysis, and will not be asked to consider early study completion for efficacy. For additional 
details, refer to the SDMC Charter. 
10.1.6 
Dissemination of Clinical Study Data  
The Sponsor is responsible for preparing and providing the appropriate regulatory authorities 
with clinical study reports, according to the applicable regulatory requirements. 
A description of this clinical study will be available on http://www.clinicaltrials.gov, as will the 
summary of the main study results when they are available. 
10.1.7 
Biological Specimens and Data  
Study data are protected by using a subject identification number, which is a number specific to 
the subject. The Investigator is in control of the information that is needed to connect a study 
sample to a subject; a subject may withdraw consent at any time by notifying the Investigator. If 
consent is withdrawn, any samples collected prior to that time may still be given to and used by 
the Sponsor, but no new data or samples will be collected unless specifically required to monitor 
the safety of the subject.  
Leftover samples stored for future research with subject consent will be labeled with a sample 
identification number. If the subject consents to have his/her samples used for future research, 
this additional research may not start immediately and may start at any time during the storage 
period. The subject’s sample(s) will be stored by the Sponsor with similar samples in a secure 
laboratory. The subject’s samples will not be kept for more than 25 years after the end of the 

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study in which they were collected. If the subject chooses not to allow his/her study samples to 
be used for future research, the samples will be destroyed by the Sponsor once they are no longer 
required for the main study. If future use consent is withdrawn, the Sponsor and the Investigator 
will ensure that the subject’s sample(s) are destroyed unless the identification number has been 
removed and the subject can no longer be linked to any samples. However, if the subject’s 
sample has already been used for research, the Sponsor is not required to destroy the results of 
this research. In this case, only the remaining sample(s) will be destroyed. 
10.1.8 
Data Quality Assurance 
All subject data relating to the study will be recorded on printed or eCRF unless transmitted to 
the Sponsor or designee electronically (eg, laboratory data). The Investigator is responsible for 
verifying that data entries are accurate and correct by physically or electronically signing the 
CRF. 
Guidance on completion of CRFs will be provided in eCRF completion guidelines. 
The Investigator must permit study-related monitoring, audits, IRB/IEC review, and regulatory 
agency inspections and provide direct access to source documents. 
Monitoring details describing strategy, including definition of study critical data items and 
processes (eg, risk-based initiatives in operations and quality such as risk management and 
mitigation strategies and analytical risk-based monitoring), methods, responsibilities, and 
requirements, including handling of noncompliance issues and monitoring techniques (central, 
remote, or on-site monitoring) are provided in the monitoring plan and centralized monitoring 
plan. 
The Sponsor or designee is responsible for the data management of this study, including quality 
checking of the data. 
The Sponsor assumes accountability for actions delegated to other individuals (eg, contract 
research organizations). 
See Section 10.1.8.1 for details regarding study monitoring and Section 10.1.8.2 for details 
regarding the audit process. 
10.1.8.1 
Monitoring 
The Sponsor and any third party to whom aspects of study management or monitoring have been 
delegated, will undertake their roles in accordance with all applicable regulations and ICH 
E6(R2). 
A representative of the Sponsor and/or its designee will perform periodic monitoring of the study 
to ensure compliance with ICH GCP guidelines and regulatory requirements. The Sponsor’s 
designated representatives (the Study Monitors) will inspect the site’s study documentation 
(including qualification and training of site personnel, IRB communications, etc), study data, 
subjects’ original medical records, and completed eCRFs. The Investigator agrees to allow 
unblinded Study Monitors to inspect the drug storage area, IP stocks, drug accountability 
records, subject charts, original study source documents (regardless of media), and other records 
relative to study conduct. The Study Monitors will maintain frequent contact with the 

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investigational site and meet with the Investigator and site staff throughout the course of the 
study. 
The Investigator will facilitate monitoring activities and the Study Monitors’ access to required 
records. 
During scheduled monitoring visits, the Investigator and the investigational site staff must be 
available to meet with the Study Monitor in order to discuss the progress of the study, make 
necessary corrections to eCRF entries, respond to data clarification requests, and respond to any 
other study-related inquiries from the Study Monitor. 
10.1.8.2 
Audits/Inspections  
To ensure compliance with GCP and all applicable regulatory requirements, the Sponsor or its 
authorized representatives may conduct a quality assurance audit. Local or foreign regulatory 
authorities may conduct regulatory inspections. Regulatory inspections may be in response to a 
marketing application, and this may occur years after completion of the clinical study. 
Authorized representatives of the Sponsor, a regulatory authority, an IEC, and/or an IRB may 
visit the site to perform audits or inspections, including review of original medical records. The 
purpose of a Sponsor audit or regulatory inspection is to systematically and independently 
examine all study-related activities and documents to determine whether these activities were 
conducted, and data were recorded, analyzed, and accurately reported according to the protocol, 
ICH GCP guidelines, and any applicable regulatory requirements. 
Initial IRB/IEC approval, and all materials approved by the IRB/IEC for this study, including the 
ICF and recruitment materials, must be maintained by the Investigator and made available for 
inspection.  
In addition to the above, representatives of the Sponsor auditing staff or government inspectors 
may review the conduct/results of the study at the investigational site. The Investigator should 
contact the Sponsor immediately if contacted by a regulatory agency about an inspection. The 
Investigator cooperates with the auditor(s), makes available to the auditor all requested 
documentation, and ensures that issues detected during these audits are satisfactorily resolved. 
The Investigator supplies the Sponsor with copies of all documentation and correspondence 
related to regulatory agency audits as outlined in the Clinical Trial Agreement. If the results of 
the audit result in a Form FDA 483 (or similar document from another regulatory agency), the 
Investigator promptly provides a copy to a Sponsor representative and a draft response to the 
Sponsor prior to submission to the regulatory agency. 
10.1.9 
Data Capture and Management 
Clinical Data Management (CDM) will be performed according to the Data Management Plan 
(DMP). The DMP will document procedures and roles and responsibilities related to CDM 
activities, including data validation, data transfer and reconciliation, CDM communications, 
medical coding and dictionaries, CDM reports, and data formats. An electronic data capture 
system compliant with 21 CFR Part 11 will be used for data collection and query handling. The 
Investigator will ensure that data are recorded in the eCRFs as specified in the study protocol and 
in accordance with the eCRF completion guidelines provided. The Investigator ensures the 
accuracy, completeness, and timeliness of the data recorded and of the provision of answers to 

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data queries. The Investigator will sign the completed eCRFs electronically. Upon completion of 
the study, a copy of the completed eCRFs will be provided to the study site for archival 
purposes. 
10.1.10 
Source Documents 
Source documents provide evidence for the existence of the subject and substantiate the integrity 
of the data collected. Source documents are filed at the Investigator’s site. 
Data reported on the CRF or entered in the eCRF that are transcribed from source documents 
must be consistent with the source documents or the discrepancies must be explained. The 
Investigator may need to request previous medical records or transfer records, depending on the 
study. Also, current medical records must be available. 
The Investigator must maintain accurate documentation (source data) that supports the 
information entered in the CRF. 
The Sponsor or designee will perform monitoring to confirm that data entered into the CRF by 
authorized site personnel are accurate, complete, and verifiable from source documents; that the 
safety and rights of subjects are being protected; and that the study is being conducted in 
accordance with the currently approved protocol and any other study agreements, ICH GCP, and 
all applicable regulatory requirements. 
10.1.11 
Records Retention 
Essential documents should be retained until at least 2 years after the last approval of a 
marketing application in an ICH region and until there are no pending or contemplated marketing 
applications in an ICH region or at least 2 years have elapsed since the formal discontinuation of 
clinical development of the IP. These documents should be retained for a longer period, 
however, if required by applicable regulatory requirement. 
The Investigator may not destroy any study records without written permission from the 
Sponsor. 
10.1.12 
Study and Site Start and Closure 
First Act of Recruitment 
The study start date is the date on which the clinical study will be open for recruitment of 
subjects. 
The first act of recruitment is the first subject enrolled. 
Study/Site Termination 
The Sponsor or designee reserves the right to close a study site or suspend/terminate the study at 
any time for any reason at the sole discretion of the Sponsor. Study sites will be closed upon 
study completion. A study site is considered closed when all required documents and study 
supplies have been collected and a study-site closure visit has been performed. 
The Investigator may initiate study-site closure at any time, provided there is reasonable cause 
and sufficient notice is given in advance of the intended termination. 

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Reasons for the early closure of a study site by the Sponsor or Investigator may include but are 
not limited to: 
For site termination: 
x Failure of the Investigator to comply with the protocol, the requirements of the IRB/IEC 
or local health authorities, the Sponsor’s procedures, or GCP guidelines 
x Inadequate or no recruitment (evaluated after a reasonable amount of time) of subjects by 
the Investigator 
x Total number of subjects included earlier than expected 
The reasons for suspending or terminating the study may include, but are not limited to, the 
following: 
x The incidence or severity of AEs in this or other studies indicates a potential health 
hazard to participants. 
x Participant enrollment is unsatisfactory. 
x Noncompliance that might significantly jeopardize the validity or integrity of the study. 
x Sponsor decision to terminate development. 
If the Sponsor determines that temporary suspension or termination of the study is required, the 
Sponsor will discuss the reasons for taking such action with all participating Investigators. When 
feasible, the Sponsor will provide advance notice to all participating Investigators of the 
impending action. 
If the study is suspended or terminated for safety reasons, the Sponsor will promptly inform all 
Investigators and/or institutions conducting the study. The Sponsor will also promptly inform the 
relevant regulatory authorities of the suspension/termination along with the reasons for such 
action. Where required by applicable regulations, the Investigator must inform the IRB or IEC 
promptly and provide the reason(s) for the suspension/termination. If the study is suspended for 
safety reasons and it is deemed appropriate by the Sponsor to resume the study, approval from 
the relevant regulatory authorities (and IRBs/IECs when applicable) will be obtained prior to 
resuming the study. 
10.1.13 
Publication Policy 
The Sponsor is responsible for preparing and providing the appropriate regulatory authorities 
with clinical study reports, according to the applicable regulatory requirements. 
 
 

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10.2 
Appendix 2: Adverse Events and Serious Adverse Events: Definitions and 
Procedures for Recording, Evaluating, Follow-up, and Reporting 
10.2.1 
Definition of AE 
AE Definition 
x An AE is any untoward medical occurrence in a subject administered a pharmaceutical 
product and that does not necessarily have a causal relationship with this treatment. An 
AE can therefore be any unfavorable and unintended sign (including an abnormal 
laboratory finding), symptom, or disease (new or exacerbated) temporally associated with 
the use of an IP, whether or not considered related to the IP. 
Events Meeting the AE Definition 
x Any abnormal laboratory test results (hematology, clinical chemistry, or urinalysis) or 
other safety assessments (eg, ECG, radiological scans, vital signs measurements), 
including those that worsen from baseline, considered clinically significant in the medical 
and scientific judgment of the Investigator (ie, not related to progression of underlying 
disease, or more severe than expected for the subject’s condition) 
x Exacerbation of a chronic or intermittent pre-existing condition including either an 
increase in frequency and/or intensity of the condition 
x New condition detected or diagnosed after IP administration even though it may have 
been present before the start of the study 
x Signs, symptoms, or the clinical sequelae of a suspected drug-drug interaction 
x Signs, symptoms, or the clinical sequelae of a suspected overdose of either IP or a 
concomitant medication. Overdose per se will not be reported as an AE/SAE unless it is 
an intentional overdose taken with possible suicidal/self-harming intent. Such overdoses 
should be reported regardless of sequelae. 
Events not Meeting the AE Definition 
x Any abnormal laboratory findings or other abnormal safety assessments that are 
associated with the underlying disease, unless judged by the Investigator to be more 
severe than expected for the subject’s condition 
x The disease/disorder being studied or expected progression, signs, or symptoms of the 
disease/disorder being studied, unless more severe than expected for the subject’s 
condition 
x Medical or surgical procedure (eg, endoscopy, appendectomy): the condition that leads to 
the procedure is the AE 
x Situations in which an untoward medical occurrence did not occur (social and/or 
convenience admission to a hospital) 
x Anticipated day-to-day fluctuations of preexisting disease(s) or condition(s) present or 
detected at the start of the study that do not worsen 

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10.2.2 
Definition of SAE 
An SAE is defined as any untoward medical occurrence that, at any dose, meets one or more of 
the criteria listed: 
x Results in death 
x Is life-threatening 
The term life-threatening in the definition of serious refers to an event in which the subject was 
at risk of death at the time of the event. It does not refer to an event, which hypothetically might 
have caused death, if it were more severe. 
x Requires inpatient hospitalization or prolongation of existing hospitalization 
 In general, hospitalization signifies that the subject has been admitted (usually 
involving at least an overnight stay) at the hospital or emergency ward for 
observation and/or treatment that would not have been appropriate in the physician’s 
office or outpatient setting. Complications that occur during hospitalization are AEs. 
If a complication prolongs hospitalization or fulfills any other serious criteria, the 
event is serious. When in doubt as to whether hospitalization occurred or was 
necessary, the AE should be considered serious. 
 Hospitalization for elective treatment of a pre-existing condition that did not worsen 
from baseline is not considered an AE. 
x Results in persistent or significant disability/incapacity 
 The term disability means a substantial disruption of a person’s ability to conduct 
normal life functions. 
 This definition is not intended to include experiences of relatively minor medical 
significance such as uncomplicated headache, nausea, vomiting, diarrhea, influenza, 
and accidental trauma (eg, sprained ankle) that may interfere with or prevent 
everyday life functions but do not constitute a substantial disruption. 
x Is a congenital anomaly/birth defect 
x Other situations: 
 Medical or scientific judgment should be exercised by the Investigator in deciding 
whether SAE reporting is appropriate in other situations such as important medical 
events that that may not be immediately life-threatening or result in death or 
hospitalization but may jeopardize the subject or may require medical or surgical 
intervention to prevent one of the other outcomes listed in the above definition. These 
events should usually be considered serious. 
o Examples of such events include invasive or malignant cancers, intensive 
treatment in an emergency room or at home for allergic bronchospasm, blood 
dyscrasias, convulsions not resulting in hospitalization, or development of 
intervention dependency or intervention abuse. 

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10.2.3 
Recording and Follow-Up of AEs and/or SAEs 
AE and SAE Recording 
When an AE/SAE occurs, it is the responsibility of the Investigator to review all documentation 
(eg, hospital progress notes, laboratory reports, and diagnostics reports) related to the event. 
The Investigator will then record all relevant AE/SAE information. 
It is not acceptable for the Investigator to send photocopies of the subject’s medical records to 
the Sponsor in lieu of completion of the required form. 
There may be instances when copies of medical records for certain cases are requested. In this 
case, all subject identifiers, with the exception of the subject number, will be redacted on the 
copies of the medical records before submission. 
The Investigator will attempt to establish a diagnosis of the event based on signs, symptoms, 
and/or other clinical information. Whenever possible, the diagnosis (not the individual 
signs/symptoms) will be documented as the AE/SAE. 
Follow-up of Adverse Events and Serious Adverse Events 
The Investigator is obligated to perform or arrange for the conduct of supplemental 
measurements and/or evaluations as medically indicated or as requested by the Sponsor to 
elucidate the nature and/or causality of the AE or SAE as fully as possible. This may include 
additional laboratory tests or investigations, histopathological examinations, or consultation with 
other health care professionals. 
[If a subject dies during participation in the study or during a recognized follow-up period, the 
Investigator will provide the Sponsor with a copy of any postmortem findings including 
histopathology.] 
New or updated information will be recorded in the originally submitted documents. 
The Investigator will submit any updated SAE data to the Sponsor within 24 hours of receipt of 
the information. 
10.2.4 
Reporting of SAEs 
SAE Reporting via an Electronic Data Collection Tool 
The primary mechanism for reporting an SAE will be the electronic data collection tool. 
If the electronic system is unavailable, then the site will use the paper SAE data collection tool 
(see next section) to report the event within 24 hours. The site will enter the SAE data into the 
electronic system as soon as it becomes available. 
After the study is completed at a given site, the electronic data collection tool will be taken 
offline to prevent the entry of new data or changes to existing data. 
If a site receives a report of a new SAE from a study subject or receives updated data on a 
previously reported SAE after the electronic data collection tool has been taken offline, then the 
site can report this information on a paper SAE form (see next section). 
Contacts for SAE reporting can be found in Section 8.4.7. 

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Note that AESIs, pregnancies, overdose, or misuse experienced by a subject during the study, 
whether or not judged related to investigational product, must also be reported within 24 hours of 
knowledge of the event.  
SAE Reporting via Paper Data Collection Tool 
Note that SAE reporting via paper forms will only serve as backup if the electronic system were 
to be temporarily unavailable due to unforeseen reasons. This will ensure safety events are still 
reported within 24 hours of knowledge of the event. Initial reporting via email or fax does not 
replace the need for the Investigator to complete and sign the SAE data collection tool within the 
electronic system. In such cases, the electronic SAE form will be completed within the electronic 
system when it becomes available. 
The paper SAE report forms are available in the Investigator site file and must be completed by 
the PI by signing and dating the SAE report form, verifying the accuracy of the information 
recorded in the form with the source documents, and sending the SAE form to the Sponsor.  
Contacts for SAE reporting can be found in Section 8.4.7. 
 

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10.3 
Appendix 3: Contraceptive Guidance 
Highly effective methods of contraception are provided in Table 6. 
Table 6 
Highly Effective Methods of Contraception 
Physical Methods 
Hormonal Methods a 
Intrauterine device  
Intrauterine hormone-releasing system b 
Bilateral tubal occlusion 
Vasectomized partner c 
Sexual abstinence d 
Combined (estrogen and progestogen-containing 
hormonal contraception) 
PO (combined pill) 
Injectable 
Transdermal (patch) 
Progestogen-only hormonal contraception associated 
with inhibition of ovulation e 
Injectable 
Implantable 
Intravaginal 
PO = oral(ly). 
a 
A change in birth control method is allowed during the study. If a change occurs, unless the subject is 
changing the method to complete abstinence, the subject must employ a barrier method in addition to the 
highly effective method of contraception for at least 2 months.  
b 
This is also considered to be a hormonal method. 
c 
A vasectomized partner is a highly effective method of birth control provided that partner is the sole sexual 
partner of the woman of childbearing potential study subject and that the vasectomized partner has received 
medical assessment of the surgical success. 
d 
Sexual abstinence is considered a highly effective method only if defined as refraining from heterosexual 
intercourse during the entire period of the study and if it is the preferred and usual lifestyle of the subject. 
e 
Progestogen-only hormonal contraception where inhibition of ovulation is not the primary mode of action 
(minipill) is not accepted as a highly effective method. 
 
 
 

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10.4 
Appendix 4: Liver Safety: Suggested Actions and Follow-up Assessments 
This Appendix describes the process to be followed to identify and appropriately report potential 
Hy’s Law (PHL) cases and Hy’s Law (HL) cases. It is not intended to be a comprehensive guide 
to the management of elevated liver biochemistries.  
During this study, the Investigator will remain vigilant for increases in liver biochemistry. The 
Investigator is responsible for determining whether a subject meets potential PHL criteria at any 
point during the study. 
All sources of laboratory data are appropriate for the determination of PHL and HL events; this 
includes samples taken at scheduled study visits and other visits including central and all local 
laboratory evaluations even if collected outside of the study visits; for example, PHL criteria 
could be met by an elevated alanine aminotransferase (ALT) from a central laboratory and/or 
elevated total bilirubin (TBL) from a local laboratory. 
The Investigator will also review AE data (for example, for AEs that may indicate elevations in 
liver biochemistry) for possible PHL events. 
The Investigator participates, together with the Sponsor’s clinical project representatives, in 
review and assessment of cases meeting PHL criteria to agree whether HL criteria are met. Hy’s 
Law criteria are met if there is no alternative explanation for the elevations in liver biochemistry 
other than drug-induced liver injury caused by the IP. 
The Investigator is responsible for recording data pertaining to PHL/HL cases and for reporting 
SAEs and AEs according to the outcome of the review and assessment in line with standard 
safety reporting processes. 
Definitions 
PHL is defined as: 
x Aspartate aminotransferase (AST) or ALT ≥ 3 × upper limit of normal (ULN) together 
with TBL ≥ 2 × ULN at any point during the study following the start of IP irrespective 
of an increase in alkaline phosphatase (ALP).  
HL is defined as: 
x AST or ALT ≥ 3 × ULN together with TBL ≥ 2 × ULN, where no other reason, other 
than the IP, can be found to explain the combination of increases, eg, elevated ALP 
indicating cholestasis, viral hepatitis, or another drug. 
For PHL and HL, the elevation in transaminases must precede or be coincident with (ie, on the 
same day) the elevation in TBL, but there is no specified timeframe within which the elevations 
in transaminases and TBL must occur. 
To identify cases of PHL, it is important to perform a comprehensive review of laboratory data 
for any subject who meets any of the following identification criteria in isolation or in 
combination: 
x ALT ≥ 3 × ULN 
x AST ≥ 3 × ULN 
x TBL ≥ 2 × ULN 

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10.5 
Appendix 5: National Institute of Allergy and Infectious Disease and Food and 
Allergy Anaphylaxis Network Guidance for Anaphylaxis Diagnosis 
National Institute of Allergy and Infectious Disease (NIAID) and Food and Allergy Anaphylaxis 
Network (FAAN) define anaphylaxis as a serious allergic reaction that is rapid in onset and may 
cause death (Sampson et al, 2006). They recognize 3 categories of anaphylaxis, with criteria 
designated to capture from 80% of cases (Category 1) to > 95% of all cases of anaphylaxis (for 
all 3 categories). 
1. Acute onset of an illness (minutes to several hours) with involvement of the skin, 
mucosal tissue, or both (eg, generalized hives, pruritus or flushing, swollen lips-tongue-
uvula), AND AT LEAST ONE OF THE FOLLOWING: 
a. Respiratory compromise (eg, dyspnea, wheeze-bronchospasm, stridor, reduced peak 
expiratory function [PEF], hypoxemia). 
b. Reduced blood pressure or associated symptoms of end-organ dysfunction (eg, 
hypotonia [collapse], syncope, incontinence). 
2. Two or more of the following that occur rapidly after exposure to a likely allergen for 
that patient (minutes to several hours): 
a. Involvement of the skin-mucosal tissue (eg, generalized hives, itch-flush, swollen 
lips-tongue-uvula). 
b. Respiratory compromise (eg, dyspnea, wheeze-bronchospasm, stridor, reduced PEF, 
hypoxemia). 
c. Reduced blood pressure or associated symptoms (eg, hypotonia [collapse], syncope, 
incontinence). 
d. Persistent gastrointestinal symptoms (eg, crampy abdominal pain, vomiting). 
3. Reduced blood pressure after exposure to known allergen for that subject (minutes to 
several hours): 
a. Infants and children ─ low systolic blood pressure (age specific) or greater than 
30% decrease in systolic blood pressure. 
b. Adults ─ systolic blood pressure of less than 90 mmHg or greater than 30% decrease 
from that patient’s baseline. 

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10.6 
Appendix 6: Study-Specified Opportunistic Infections 
The study-specified opportunistic infections that will monitored in this study are provided in 
Table 7. 
Table 7 
Study-Specified Opportunistic Infections 
Definite a,b Opportunistic Infection 
Probable c Opportunistic Infection 
Pneumocystis jirovecii 
BK virus disease, including polyomavirus-associated 
nephropathy  
CMV disease 
Post-transplant lymphoproliferative disorder (EBV) 
Progressive multifocal leukoencephalopathy 
Bartonellosis (disseminated disease only) 
Blastomycosis 
Toxoplasmosis 
Coccidioidomycosis 
Histoplasmosis 
Aspergillosis (invasive disease only) 
Candidiasis (invasive disease or pharyngeal) 
Cryptococcosis 
Other invasive fungi: Mucormycosis (zygomycosis) 
(Rhizopus, Mucor, and Lichtheimia), 
Scedosporium/Pseudallescheria boydii, Fusarium) 
Legionellosis 
Listeria monocytogenes (invasive disease only) 
TB 
Nocardiosis 
Non-tuberculous mycobacterium disease 
Salmonellosis (invasive disease only) 
HBV reactivation 
Herpes simplex (invasive disease only) 
Herpes zoster (any form) 
Strongyloides  
(hyperinfection syndrome and disseminated forms only) 
Paracoccidioides infections 
Penicillium marneffei (talaromyces) 
Sporothrix schenckii 
Cryptosporidium species  
(chronic disease only) 
Microsporidiosis 
Leishmaniasis (visceral only) 
Trypanosoma cruzi infection  
(Chagas’s disease) (disseminated disease only) 
Campylobacteriosis (invasive disease only) 
Shigellosis (invasive disease only) 
Vibriosis  
(invasive disease due to Vibrio vulnificus) 
HCV progression 
CMV = cytomegalovirus; EBV = Epstein-Barr virus; HBV = hepatitis B virus; HCV = hepatitis C virus; 
TB = tuberculosis 
a 
Generally does not occur in the absence of immunosuppression, but whose presence indicates a potential or 
likely alteration in host immunity. 
b 
Can occur in subjects without recognized forms of immunosuppression, but whose presence indicates a 
potential or likely alteration in host immunity. 
c 
Published data are currently lacking, but expert opinion believes that risk is likely elevated in the setting of 
biologic therapy. 
Source: Winthrop et al, 2015 

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10.7 
Appendix 7: Prednisone Equivalent of Oral Glucocorticoid Dose 
Oral GCs other than prednisone may be used PO at the equivalent doses shown in Table 8. 
 
 
 
 

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10.8 
Appendix 8: Recommended Oral Glucocorticoid Tapering Schedule 
To provide guidance to Investigators, a recommended OGC tapering regimen is provided in 
Table 9. 
Table 9 
Recommended Oral Glucocorticoid Tapering Schedule 
Visit  
Dose of Oral Prednisone or Equivalent at Start of Study a 
Week 0 
40 mg 
30 mg 
20 mg 
10 mg 
7.5 mg b 
Week 4 
30 mg 
22.5 mg 
15 mg 
7.5 mg 
5 mg 
Week 8 
20 mg 
15 mg 
10 mg 
5 mg 
4 mg  
Week 12 
12.5 mg 
10 mg 
7.5 mg 
4 mg  
3 mg 
Week 16 
7.5 mg 
7.5 mg 
5 mg 
3 mg 
2 mg 
Week 20 
5 mg 
5 mg 
4 mg  
2 mg 
1 mg  
Week 24 
4 mg  
4 mg  
3 mg 
1 mg  
Discontinue 
Week 28 
3 mg 
3 mg 
2 mg 
Discontinue 
Discontinue 
Week 32 
2 mg 
2 mg 
1 mg  
Discontinue 
Discontinue 
Week 36 
1 mg  
1 mg  
Discontinue 
Discontinue 
Discontinue 
Week 40 
Discontinue 
Discontinue 
Discontinue 
Discontinue 
Discontinue 
Week 44 
Discontinue 
Discontinue 
Discontinue 
Discontinue 
Discontinue 
Week 48 
Discontinue 
Discontinue 
Discontinue 
Discontinue 
Discontinue 
OGC = oral glucocorticoid 
The OGC tapering schedule represents an example of a tapering regimen to provide guidance to Investigators in the 
approach to steroid taper throughout the study with the aim to lower the daily dose OGC to total discontinuation 
if clinically possible throughout the study.  
a 
Specified prednisone dose is dose at the beginning of the week. 
b 
Subjects entering study at < 7.5 mg/day dose of OGC must taper until full discontinuation if clinically possible. 
It is encouraged that Investigators taper each month by at least 1 mg/day. 
 
 
 

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11 
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