A Multicenter, Randomized, Double-Blind, Placebo-Controlled Phase 3 Trial to Evaluate Efficacy and Safety of Lenabasum in Dermatomyositis
Phase: PHASE3
Conditions: Dermatomyositis
Sponsor: Corbus Pharmaceuticals Inc.

Lenabasum 
Corbus Pharmaceuticals Inc. 
Clinical Trial Protocol: JBT101-DM-002 
13 Jan 2021; Version 2.2 
 
 
 
CLINICAL TRIAL PROTOCOL 
DETERMINE STUDY 
A Multicenter, Randomized, Double-Blind, Placebo-Controlled Phase 3 Trial 
to Evaluate Efficacy and Safety of Lenabasum in Dermatomyositis 
Protocol Number: 
JBT101-DM-002 
Version 
2.2  
Study Product: 
Lenabasum  
Investigational New 
Drug number: 
116313 
EudraCT number: 
2018-003273-10 
 
Indication: 
Dermatomyositis 
Phase: 
3 
Date of Protocol:  
13 Jan 2021 
Name and Affiliation of 
Coordinating Principal 
Investigators: 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
  
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
Responsible Medical 
Officer:  
 
 
 
 
 
 
 
 
  
 
 
 
Sponsor:  
Corbus Pharmaceuticals, Inc. 
500 River Ridge Drive, Second Floor  
Norwood, MA 02062 USA 
Statement of Compliance 
This trial will be carried out in accordance with the International Council for Harmonisation of Technical 
Requirements for Pharmaceuticals for Human Use (ICH), Good Clinical Practice (GCP),  Japanese Good Clinical 
Practice (J-GCP), the Ministerial Ordinance on Good Clinical Practice for Drugs in Japan (where applicable), and 
United States (US) Code of Federal Regulations (CFR) applicable to clinical studies (45 CFR Part 46, 21 CFR Part 
50, 21 CFR Part 56, 21 CFR Part 312, and/or 21 CFR Part 812), including the archiving of essential documents. 
 
Confidentiality Statement 
The information in this document is confidential and is proprietary to Corbus Pharmaceuticals, Inc. It is understood 
that information in this document shall not be disclosed to any third party, in any form, without prior written consent 
of Corbus Pharmaceuticals, Inc.

Lenabasum 
Corbus Pharmaceuticals Inc. 
Clinical Trial Protocol: JBT101-DM-002 
13 Jan 2021; Version 2.2 
 
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INVESTIGATOR AGREEMENT 
PROTOCOL JBT101-DM-002 
I agree: 
• To assume responsibility for the proper conduct of this clinical study at this site and 
to conduct the study in compliance with this protocol, any future amendments, and 
with any other study conduct procedures provided by the sponsor. 
• That I am aware of, and will comply with, the internationally recognized code of 
Good Clinical Practices and all other applicable regulatory requirements to obtain 
written and dated approval from the Ethics Committee for the study protocol, written 
informed consent, informed consent form updates, subject recruitment procedures 
(e.g., advertisements), and any other written information to be provided to the 
subjects, before initiating this clinical study. 
• Not to implement any changes to or deviations from the protocol without prior 
agreement from the sponsor except to eliminate an immediate hazard to the study 
subjects, or when changes involve only logistical or administrative aspects of the 
clinical study. 
• To permit direct monitoring and auditing by the sponsor or sponsor’s representatives 
and inspection by the appropriate regulatory authorities.  
• That I am thoroughly familiar with the appropriate use of the study drugs, as 
described in this protocol, and any other information provided by the sponsor or 
designee, including, but not limited to, the current Investigator’s Brochure or 
equivalent document and approved product label (if applicable). 
• To provide sufficient time and an adequate number of qualified staff and facilities for 
the foreseen duration of the clinical study to conduct the study properly, ethically, and 
safely. 
• To ensure that all persons assisting in this study are adequately informed about the 
protocol, study drugs, and their clinical study-related duties and functions. 
 
_________________________________________________ 
_____________________ 
Investigator Signature  
Date 
 
_______________________________________________ 
Printed Name and Title of Investigator 
 
Site # _______ 
 
Site Name _________________________________ 

Lenabasum 
Corbus Pharmaceuticals Inc. 
Clinical Trial Protocol: JBT101-DM-002 
13 Jan 2021; Version 2.2 
 
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Study Design: This is a Phase 3, multicenter, interventional, double-blind, randomized, placebo-
controlled study designed to assess the efficacy and safety of lenabasum in subjects with DM.  
The study consists of 2 parts: 
• Part A: Double-Blind, Placebo Controlled Phase 
• Part B: Open Label Extension Phase (Optional)  
The overall design for this study is summarized in Figure 1 of the protocol.   
Part A Double-Blind, Placebo Controlled Phase 
The initial plan is for approximately 150 dosed subjects to receive at least 1 dose of study 
product.  The final number of subjects to be dosed will be decided after a blinded interim 
analysis. The timing and methods for the interim analyses will be outlined in the statistical 
analysis plan (SAP). It is expected that approximately 200 subjects will be screened to dose 150 
subjects. Subjects will be randomized to receive lenabasum 20 mg, lenabasum 5 mg, or placebo 
twice-daily (BID) in a 2:1:2 ratio. It is hypothesized that subjects receiving lenabasum will have 
greater improvement in the TIS score (2016 ACR/EULAR Myositis Response Criteria) at Week 
28 compared to subjects receiving placebo.   
The total duration of participation for an individual subject is approximately 60 weeks and 
includes the following: a screening visit (up to 4 weeks before Visit 1), up to 52-week treatment 
period, and a Safety Follow-up Visit that will be conducted 4 ± 1 weeks after the last visit. 
Subjects will be assessed for safety and efficacy parameters every 6 weeks (except for Visit 2, 
which will occur 4 weeks after Visit 1) for a total of up to 10 treatment visits.  Study personnel 
will also contact subjects by telephone halfway between Visit 9 and Visit 10 (Week 49 ± 1) to 
assess compliance, safety and overall status of DM, if applicable.   
A subject’s corticosteroid or other immunosuppressant treatments may be reduced if the 
investigator determines that clinical improvement in the subject’s dermatomyositis has occurred 
and a reduction is warranted. It is recommended that a reduction in corticosteroid or 
immunosuppressant treatment should not occur before Visit 4 or after Visit 8. A preferred 
schedule for reduction is provided in Section 5.5.1 of the protocol.  
Main Eligibility Criteria:  
• Male or female subjects ≥ 18 years of age with a known diagnosis of DM and active 
disease.  
• Must meet one of the following for DM diagnosis:  
1. Bohan and Peter’s criteria for probable or definite DM (Bohan and Peter, 1975a; 
Bohan and Peter 1975b) 
2. ACR/EULAR criteria (Lundberg et al, 2017) 
• Must meet one of the following for disease activity / severity:  
i. 
MDGA ≥ 3 cm (0  10 cm scale) and MMT-8 score ≤ 142 (out of 150 total possible) 
ii. 
Sum of MDGA, PtGA and EMGA VAS scores is ≥ 10 cm (all scales individually on 
0-10 cm scale) 
iii. 
MDGA ≥ 3 cm and CDASI activity score of > 14 

Lenabasum 
Corbus Pharmaceuticals Inc. 
Clinical Trial Protocol: JBT101-DM-002 
13 Jan 2021; Version 2.2 
 
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Doses of non-corticosteroid immunosuppressant medications should be stable for ≥ 8 weeks at 
screening. Doses of oral corticosteroids should be stable for ≥ 4 weeks at Visit 1.  
Phase: 3 
Study Sites: Up to approximately 75 sites in North American, European, and Asian Pacific 
regions. 
Study Treatment:  
All treatments: lenabasum (20 mg or 5 mg) or placebo, will be administered orally BID for up to 
52 weeks. 
Study Duration: Estimated duration for Part A is anticipated to be approximately 36 months 
from first subject first visit to last subject last visit and will depend on the rate of enrollment 
across the various sites. 
Statistical Methodology: It is planned that about 150 subjects will be dosed at a ratio of 2:1:2 to 
lenabasum 20 mg, lenabasum 5 mg, or placebo arms, respectively, with a total of 120 subjects 
expected to complete the study (assuming ~ 20% drop out rate).  A total of 120 subjects (48 
subjects each in the 20 mg BID and placebo groups, and 24 subjects in the 5 mg BID dose group) 
achieves 95% power to detect a significant difference in the TIS score between the lenabasum 20 
mg BID group and placebo. This assumes a two-sided test at alpha = 0.05 and a common 
standard deviation of 20.00 in both treatment arms for the primary efficacy outcome, and a 
difference in the TIS between lenabasum 20 mg BID and placebo of 15.0. The number of 
subjects to be randomized may be adjusted further during the study after a blinded interim 
analysis of the emerging data. The intent is to perform a blinded interim examination of the 
variance of the TIS to potentially increase the sample size to maintain power (with no statistical 
adjustment to the alpha level required). The projected maximum number of subjects to be 
randomized is about 230 subjects (for 183 completers), which corresponds to standard deviation 
of 30.00, and 85% power.  
Randomization will be stratified based on screening MMT-8 score (< 135 or ≥ 135), prednisone 
dose (≤ 10 mg or > 10 mg per day or equivalent), and region (US vs. ex-US). The primary 
efficacy variable is the TIS. The primary analysis is to compare the TIS at Week 28 between the 
lenabasum 20 mg BID treated group and the placebo group using a mixed model for repeated 
measures (MMRM). The model will have TIS score as a dependent variable, treatment, visit, 
treatment*visit interaction as factors, Baseline MMT-8 score, prednisone use, and region as 
covariates, and subject as the repeated random effect using an unstructured covariance matrix. 
Two-sided p-values and 95% confidence intervals associated with the least-square (LS) mean 
difference between the lenabasum group and placebo will be presented for each visit.  If the 
distribution of the TIS score does not meet the assumptions of normality, a nonparametric 
analysis may be performed (e.g., MMRM analysis on the ranked data). 
Continuous secondary and tertiary outcome variables will be analyzed similarly to the primary 
MMRM model, using change from Baseline as the dependent variable, with the Baseline of each 
endpoint also included in the model.  Other outcomes based on the proportion of subjects 
achieving defined criteria will be analyzed using a Fisher’s exact or Cochran-Mantel-Haenzel 
test.   

Lenabasum 
Corbus Pharmaceuticals Inc. 
Clinical Trial Protocol: JBT101-DM-002 
13 Jan 2021; Version 2.2 
 
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All primary and secondary efficacy analyses will be two-sided at the 0.05 significance level.  
The overall Type I error rate will be controlled for the primary and secondary efficacy outcomes 
with independent hierarchical assessments of efficacy at each comparison of lenabasum to 
placebo.  The order of the tests for treatment effect will be as follows: 
• Primary efficacy outcome (at Week 28):  TIS, lenabasum 20 mg BID versus placebo. 
Change from baseline in each core set measure of the composite TIS will be presented to 
support the TIS: MDGA; PtGA; MMT-8; HAQ; muscle enzymes; EMGA 
• Secondary efficacy outcomes (Change from Baseline or proportion of subjects at Week 
28, unless otherwise specified).  The list will be done in order below for comparisons 
between lenabasum 20 mg BID and placebo cohorts: 
o Subjects who achieve DOI  
o Subjects who improve by at least one category on the IGA scale of skin activity 
o Subjects who achieve TIS ≥ 40 (at least moderate improvement) 
o TIS in subjects receiving any immunosuppressant medication for > 1 year at 
Baseline 
o TIS at Visit 10 (Week 52) 
o CDASI activity score 
The list will continue in order below for comparisons between lenabasum 5 mg BID and 
placebo cohorts: 
o TIS 
o Subjects who achieve DOI  
o Subjects who improve by at least one category on the IGA scale of skin activity 
o Subjects who achieve TIS ≥ 40 (at least moderate improvement) 
o TIS in subjects receiving any immunosuppressant medication for > 1 year at 
Baseline 
o TIS at Visit 10 (Week 52) 
o CDASI activity score 
Note that statistical significance within an endpoint must be achieved to continue in the 
assessment of the next endpoint. 
No formal statistical testing will be performed to compare the safety in lenabasum versus 
placebo cohorts. The number and percentage of subjects with AEs will be summarized for each 
treatment by system organ class and preferred term. Similar summaries will be presented for AEs 
related to study product, AEs leading to permanent discontinuation of study product, SAEs, and 
AEs resulting in death. Any AE with a relationship category of possible, probable, or definite is 
considered related to study product. The AEs will be coded using the Medical Dictionary for 
Regulatory Activities (MedDRA). All reported AEs will be provided in separate data listings. 
Descriptive statistics will be used to summarize clinical laboratory parameters, vital signs and 
their corresponding change from Baseline for each treatment by scheduled timepoint. 

Lenabasum 
Corbus Pharmaceuticals Inc. 
Clinical Trial Protocol: JBT101-DM-002 
13 Jan 2021; Version 2.2 
 
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Part B Open-Label Extension Phase (Optional) 
Upon completing Part A treatment (Visit 10), at the investigator’s discretion, consenting subjects 
may directly rollover into open-label treatment (Part B). 
All subjects in the open-label extension (OLE) will receive lenabasum 20 mg BID.  
The same efficacy and safety parameters described as primary and secondary objective for Part 
A will be evaluated in Part B as described in the SAP.  
 
 

Lenabasum 
Corbus Pharmaceuticals Inc. 
Clinical Trial Protocol: JBT101-DM-002 
13 Jan 2021; Version 2.2 
 
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TABLE OF CONTENTS 
SPONSOR APPROVAL .................................................................................................................2 
INVESTIGATOR AGREEMENT...................................................................................................3 
PROTOCOL SYNOPSIS.................................................................................................................4 
TABLE OF CONTENTS ...............................................................................................................12 
ABBREVIATIONS .......................................................................................................................17 
1. 
INTRODUCTION ......................................................................................................19 
1.1. 
Study Rationale ...........................................................................................................19 
1.2. 
Background .................................................................................................................19 
1.3. 
Risk/Benefit Assessment ............................................................................................20 
2. 
OBJECTIVES AND ENDPOINTS ............................................................................22 
3. 
STUDY DESIGN .......................................................................................................26 
3.1. 
Overall Design ............................................................................................................26 
3.1.1. 
Part A: Double-Blind, Placebo-Controlled Phase ......................................................26 
3.1.2. 
Part B: Optional Open-label Extension ......................................................................27 
3.1.3. 
Study JBT101-LTS-001: 2-year Observational Safety Follow-up .............................27 
3.2. 
Scientific Rationale for Study Design ........................................................................27 
3.2.1. 
Part A: Double-blind, Placebo-controlled Phase ........................................................27 
3.2.2. 
Part B: Open-Label Extension ....................................................................................28 
3.3. 
Justification of Dose ...................................................................................................28 
4. 
STUDY POPULATION .............................................................................................29 
4.1. 
Inclusion Criteria ........................................................................................................29 
4.2. 
Exclusion Criteria .......................................................................................................30 
4.3. 
Screen Failures ............................................................................................................31 
4.4. 
Subjects Randomized Erroneously .............................................................................32 
4.5. 
Strategies for Recruitment and Retention ...................................................................32 
4.6. 
Women, Minorities, and Children (Special Populations) ...........................................33 
5. 
STUDY INTERVENTION ........................................................................................34 
5.1. 
Study Intervention(s) Administration .........................................................................34 
5.2. 
Preparation/Handling/Storage/Accountability ............................................................35 

Lenabasum 
Corbus Pharmaceuticals Inc. 
Clinical Trial Protocol: JBT101-DM-002 
13 Jan 2021; Version 2.2 
 
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5.2.1. 
Acquisition and Accountability ..................................................................................35 
5.2.2. 
Formulation, Appearance, Packaging, and Labeling ..................................................36 
5.2.3. 
Product Storage and Stability .....................................................................................36 
5.2.4. 
Preparation ..................................................................................................................37 
5.3. 
Measures to Minimize Bias: Randomization and Blinding ........................................37 
5.3.1. 
Unblinding Procedures During the Study ...................................................................38 
5.3.2. 
Unblinding Procedures at the End of Part A ..............................................................39 
5.4. 
Study Intervention Compliance ..................................................................................39 
5.5. 
Concomitant Therapy .................................................................................................39 
5.5.1. 
Guidelines for Reduction in Concurrent Immunosuppressant Medications 
including Corticosteroids ............................................................................................39 
5.5.2. 
Guidelines for New or Increased Dose of Immunosuppressive Medications 
or Rescue Treatment ...................................................................................................41 
5.5.3. 
Prohibited Medications During the Study ..................................................................41 
6. 
DISCONTINUATION OF STUDY TREATMENT, SUBJECT 
WITHDRAWAL, AND EARLY TERMINATION ...................................................42 
6.1. 
Discontinuation of Study Treatment and Subject Withdrawal ...................................42 
6.2. 
Early Termination of Study ........................................................................................43 
7. 
SCHEDULE OF ASSESSMENTS AND STUDY VISITS .......................................44 
7.1. 
Assessments ................................................................................................................44 
7.2. 
Study Visits .................................................................................................................50 
7.2.1. 
Part A ..........................................................................................................................50 
7.2.2. 
Part B ..........................................................................................................................59 
7.2.3. 
Safety Follow-up (4 ± 1 Weeks after last visit) ..........................................................62 
7.2.4. 
Unscheduled Visit .......................................................................................................63 
7.2.5. 
End of Study ...............................................................................................................63 
8. 
STUDY ASSESSMENTS AND PROCEDURES ......................................................64 
8.1. 
Efficacy Assessments .................................................................................................64 
8.1.1. 
Training in Efficacy Assessments ..............................................................................64 
8.1.2. 
Total Improvement Score (TIS) ..................................................................................64 
8.1.3. 
Definition of Improvement (DOI) ..............................................................................66 
8.1.4. 
Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI) 
Score ...........................................................................................................................66 
8.1.5. 
Investigator Global Assessment (IGA) scale of skin activity .....................................66 

Lenabasum 
Corbus Pharmaceuticals Inc. 
Clinical Trial Protocol: JBT101-DM-002 
13 Jan 2021; Version 2.2 
 
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8.1.6. 
Short-Form-36 (SF-36) ...............................................................................................66 
8.1.7. 
Corticosteroid Dose ....................................................................................................67 
8.1.8. 
Forced Vital Capacity .................................................................................................67 
8.1.9. 
Physician Global Activity (MDGA) – Likert Scale ...................................................67 
8.1.10. 
Patient Improvement Questionnaire for Physicians ...................................................67 
8.1.11. 
Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue score .............67 
8.1.12. 
5-Dimension (5-D) Itch Score ....................................................................................67 
8.1.13. 
National Institutes of Health Patient-Reported Outcomes Measurement 
Information System (PROMIS)-29 Short Form .........................................................68 
8.1.14. 
Patient Visual Analog Scale (VAS) scores of Pain ....................................................68 
8.1.15. 
Skindex-29+3 ..............................................................................................................68 
8.1.16. 
European Quality of Life 5-domain (EQ-5D) questionnaire score ............................68 
8.1.17. 
Patient Improvement Questionnaire for Subjects .......................................................68 
8.1.18. 
Blood Biomarkers of Inflammation ............................................................................69 
8.1.19. 
Paxgene .......................................................................................................................69 
8.1.20. 
Blood for Flow Cytometry ..........................................................................................69 
8.1.21. 
Autoantibodies ............................................................................................................69 
8.1.22. 
Skin Biopsies ..............................................................................................................69 
8.1.23. 
Skin Photographs ........................................................................................................69 
8.1.24. 
Pharmacokinetic Assessments ....................................................................................70 
8.2. 
Safety Assessments .....................................................................................................70 
8.2.1. 
Medical History and Use of Contraception ................................................................70 
8.2.2. 
Concomitant Medications ...........................................................................................70 
8.2.3. 
Physical Examinations ................................................................................................70 
8.2.4. 
Vital Signs, Height and Weight ..................................................................................71 
8.2.5. 
Electrocardiograms .....................................................................................................71 
8.2.6. 
Clinical Safety Laboratory Assessments ....................................................................71 
8.2.7. 
Adverse Events and Serious Adverse Events .............................................................72 
9. 
STATISTICAL CONSIDERATIONS .......................................................................78 
9.1. 
Statistical Hypotheses .................................................................................................78 
9.1.1. 
Primary Efficacy Endpoint .........................................................................................78 
9.2. 
Sample Size Determination ........................................................................................78 
9.3. 
Populations for Analyses ............................................................................................78 

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Clinical Trial Protocol: JBT101-DM-002 
13 Jan 2021; Version 2.2 
 
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9.4. 
Statistical Analyses .....................................................................................................79 
9.4.1. 
General Approach .......................................................................................................79 
9.4.2. 
Analysis of the Primary Efficacy Endpoint(s) ............................................................80 
9.4.3. 
Analysis of the Secondary Efficacy Endpoint(s) ........................................................80 
9.4.4. 
Analyses of the Tertiary Efficacy Endpoints ..............................................................81 
9.4.5. 
Analyses of Pharmacokinetic Endpoints ....................................................................81 
9.4.6. 
Analyses of Biomarker Endpoints ..............................................................................81 
9.4.7. 
Safety Analyses ..........................................................................................................81 
9.4.8. 
Baseline Descriptive Statistics ....................................................................................82 
9.4.9. 
Planned Interim Analyses ...........................................................................................82 
9.4.10. 
Tabulation of Individual Subject Data ........................................................................82 
9.4.11. 
Part B ..........................................................................................................................82 
10. 
SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS ..................................................................................................83 
10.1. 
Regulatory, Ethical, and Study Oversight Considerations .........................................83 
10.1.1. 
Ethical Conduct of the Study ......................................................................................83 
10.1.2. 
Ethics Committee/ Institutional Review Board ..........................................................83 
10.1.3. 
Informed Consent Process ..........................................................................................84 
10.1.4. 
Confidentiality and Privacy ........................................................................................85 
10.1.5. 
Future Use of Stored Specimens and Data .................................................................86 
10.1.6. 
Key Roles and Study Governance ..............................................................................87 
10.1.7. 
Safety Oversight .........................................................................................................87 
10.1.8. 
Quality Assurance and Quality Control ......................................................................88 
10.1.9. 
Data Handling and Record Keeping ...........................................................................90 
10.1.10. 
Protocol Deviations ....................................................................................................92 
10.1.11. 
Schedule and Contents of Report ...............................................................................94 
10.1.12. 
Publication and Data Sharing Policy ..........................................................................94 
11. 
REFERENCES ...........................................................................................................96 
12. 
APPENDICES ..........................................................................................................100 
APPENDIX 1. REPRODUCTIVE POTENTIAL AND ACCEPTABLE METHODS OF 
CONTRACEPTION .................................................................................................101 
APPENDIX 2. INVESTIGATOR GLOBAL ASSESSMENT OF SKIN ACTIVITY ...............102 
APPENDIX 3. PATIENT IMPROVEMENT QUESTIONNAIRE FOR PHYSICIANS ...........103 

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APPENDIX 4. PATIENT IMPROVEMENT QUESTIONNAIRE FOR SUBJECTS ................104 
APPENDIX 5. PHYSICIAN ASSESSMENT OF DM ACTIVITY ...........................................105 
APPENDIX 6. ALGORITHM TO CALCULATE TOTAL IMPROVEMENT SCORE 
(TIS) ..........................................................................................................................106 
APPENDIX 7. CORTICOSTEROID CONVERSION TABLE ..................................................107 
 
 
Table of Tables 
Table 1 
Study Products, Dose, and Mode of Administration ..................................................34 
Table 2 
Recommended Schedule for Reduction in Chronic Oral Corticosteroid Dose 
When Determined by the Investigator to be Appropriate at Visits 4-8 ......................40 
Table 3 
Schedule of Assessments – Part A ..............................................................................45 
Table 4: 
Schedule of Assessments – Part B ..............................................................................48 
Table 5: 
Description of Rating of Muscle Strength in Individual Muscle Groups for 
MMT-8 Scoring ..........................................................................................................65 
 
Table of Figures 
Figure 1: 
Study Design for JBT101-DM-002 ............................................................................26 
Figure 2: 
Rescreening of Subjects ..............................................................................................32 
 
 

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Clinical Trial Protocol: JBT101-DM-002 
13 Jan 2021; Version 2.2 
 
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1. 
INTRODUCTION 
Lenabasum (also known as JBT-101) is a novel, first-in-class “pro-resolving” small molecule 
cannabinoid type 2 receptor (CB2) agonist that is being developed for the treatment of 
inflammation and fibrosis in several diseases such as: dermatomyositis (DM), systemic sclerosis 
(SSc), systemic lupus erythematosus (SLE) and cystic fibrosis (CF). 
1.1. 
Study Rationale  
Results from the first-in-DM patient study (JBT101-DM-001) demonstrated improvement in the 
primary efficacy variable, Cutaneous Dermatomyositis Disease Area and Severity Index 
(CDASI) activity score, as well as numerous secondary efficacy measures. Lenabasum was 
shown to have a favorable safety profile in this DM study, consistent with previous clinical 
studies with lenabasum in patients with CF and SSc. Given the small sample size of study 
JBT101-DM-001 and exclusion of patients with active muscle disease, this present study is 
designed to assess the safety and efficacy of lenabasum in a larger, broader population of DM 
patients.   
1.2. 
Background 
Dermatomyositis is a severe autoimmune disease with distinctive cutaneous and muscle 
symptoms that are frequently accompanied by other manifestations. Although robust 
epidemiologic data are not available, it is estimated that < 13,500 to ~70,000 individuals in the 
United States (US) may have DM (Jacobson et al, 1997, Reeder et al, 2010). The most common 
age of onset is between 50-60 years of age (Tansley et al, 2013); however, DM has been 
observed in younger populations. Juvenile DM occurs before the age of 16 and has an incidence 
rate of around 1 case per 1 million children (Quartier et al, 2013).  
Skin findings associated with DM include rashes characterized by erythema as well as pruritus of 
the scalp, face, dorsum of the hands, and upper back (Klein et al, 2007; Goreshi et al, 2011). 
Other manifestations of DM can include: muscle weakness (Bohan et al, 1977; Koh et al, 1993; 
Volochayev et al, 2012; Na et al, 2009); pulmonary complications (Kalluri et al, 2010; 
Ascherman et al, 2002); cardiac findings (Bazzani et al, 2010), esophageal involvement (de 
Merieux et al, 1983; Marie, 2012), joint disease (Marie, 2012), and associated malignancies (Hill 
et al, 2001; Yamasaki et al, 2011). Quality of life is significantly impacted in DM patients 
(Goreshi et al, 2011). Mortality in patients with DM is high with survival estimated to be 70% at 
5 years and 57% at 10 years (Schiopu et al, 2012). 
The clinical presentation of DM is a result of underlying, unresolved chronic inflammation. 
Classic inflammatory mediators include activated immune cells and proinflammatory cytokines 
such as tumor necrosis factor α (TNFα), interleukin 1 beta (IL-1β), and type 1 interferons (IFNs) 
(Wong et al, 2012; Kim et al, 2012; Nabatian et al, 2012). Consequently, the current standard of 
care for DM includes the use of corticosteroids. Long-term systemic use of corticosteroids has 
shown to be associated with a number of adverse events (AEs) such as: osteoporosis and 
fractures; adrenal suppression; hyperglycemia and diabetes; cardiovascular disease and 
dyslipidemia, dermatological and gastrointestinal events; psychiatric disturbances; and 
immunosuppression (Liu et al, 2013). Side‐effects of corticosteroid have been reported to affect 
32% (Baron and Small, 1985) to 41% (Tymms and Webb, 1985) of treated patients with DM. In 

Lenabasum 
Corbus Pharmaceuticals Inc. 
Clinical Trial Protocol: JBT101-DM-002 
13 Jan 2021; Version 2.2 
 
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long‐term studies, disability associated with corticosteroid side‐effects, especially osteonecrosis 
and osteoporotic vertebral fractures has also been reported (Choy and Isenberg, 2002).  
If a patient is unresponsive to steroid therapy, i.e., no improvement after 3 - 6 months of 
prednisone, or if the patient relapses while tapering, a second-line immunosuppressive agent 
should be added (Findlay et al, 2015). Common second line choices include azathioprine (Bunch 
et al, 1980), methotrexate (Newman et al, 1995), and intravenous immunoglobulin (Dalakas et al, 
1993). Other agents used in the treatment of DM are rituximab (Oddis et al, 2013), 
mycophenolate mofetil (Pisoni et al, 2007), tacrolimus (Wilkes et al, 2005), cyclosporine 
(Qushmaq et al, 2000), and cyclophosphamide (Bombardieri et al, 1989). Use of second line 
agents for their steroid-sparing effect is based on empirical data, and their use as a sole treatment 
may provide little benefit (Dalakas, 2011). In addition to lack of proof of efficacy (Liu et al, 
2013), these second line immunosuppressive therapy agents are well known to be associated with 
significant side effects. Due to the severe side effects, reduction of immunosuppressive 
medication is an important goal for DM treatment. 
Lenabasum is being developed as a therapy for the treatment of inflammation and fibrosis 
through the targeting of the CB2 receptor. CB2 is mainly distributed throughout immune cells 
(Castaneda et al, 2013; Munro et al, 1993). CB2 is expressed at 10- to 100-fold higher levels than 
cannabinoid type 1 (CB1) receptor on activated immune cells (Carayon et al 1998; Galiegue et 
al, 1995; Munro et al, 1993). Cell surface expression of CB2 returns to baseline levels once the 
immune response is resolved (Carayon et al 1998). As an agonist of CB2, lenabasum triggers a 
class switch of lipid mediators to favor pro-resolving lipid mediators which facilitate the 
transition of an active innate immune response back to an inactive response (Shinohara et al, 
2012; Zurier et al, 2009).  
Lenabasum has demonstrated potent pro-resolution (anti-inflammatory, anti-fibrogenic) effects 
in multiple non-clinical and clinical models (see Sections 4 and 5 of the Investigator’s Brochure). 
A detailed description of the chemistry, pharmacology, efficacy, and safety of lenabasum is 
provided in the Investigator’s Brochure.  
1.3. 
Risk/Benefit Assessment 
Lenabasum is an investigational product not currently approved outside of clinical trial use; 
therefore, individual subjects may or may not experience a benefit from lenabasum for the 
disease condition under study. Subjects who receive placebo are unlikely to receive any benefit 
from participation in the study other than a potential placebo benefit and an opportunity to 
participate in the open-label extension (OLE) study. Individual subjects should carefully consider 
the risks versus benefits from participation in this clinical trial before signing the informed 
consent (IC). 
In multiple nonclinical studies, cells isolated from patients with inflammatory / fibrotic diseases, 
animal models of disease, and mechanism of action studies conducted in healthy volunteers, 
lenabasum has demonstrated the potential to resolve innate immune responses as well as fibrotic 
processes. Efficacy signals have been observed in Phase 2 studies in SSc (JBT101-SSc-001), CF 
(JBT101-CF-001) and DM (JBT101-DM-001). Evidence of on-target biologic effects of 
lenabasum has been shown in the skin in DM and SSc subjects and in sputum from CF subjects, 
supporting potential clinical benefit. Efficacy signals have also been observed in subjects with 

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refractory traumatic neuropathic pain (CPL7075/02/01/001/1). Anticipated AEs in clinical trials 
with lenabasum include those related to the subject population being studied, concomitant 
medications that subjects may be taking (e.g., immunosuppressive medications) and lenabasum.  
To date, the majority of AEs related to lenabasum have been mild in severity; serious adverse 
events (SAE) considered related to lenabasum have primarily been infective pulmonary 
exacerbations in subjects with CF. The most frequent AEs thought to be causally related to 
lenabasum (within 1-60 mg dose range) by the investigators include dry mouth and dizziness. 
The most frequent AEs observed in study subjects who received lenabasum in the 1-60 mg dose 
range, independent of relatedness to lenabasum, included fatigue, upper respiratory tract 
infection, infective pulmonary exacerbation (in subjects with CF), dry mouth, dizziness, cough, 
hemoptysis (in subjects with CF), and headache. Other AEs listed as class effects of CB1/CB2 
agonists (e.g., , feeling drunk or abnormal or jittery, hot or hot and cold or cold, hangover, 
feeling relaxed or feeling of movements slower than normal) have been reported in < 5% of 
lenabasum-treated subjects.  
Lenabasum has shown to inhibit human ether a-go-go (hERG) current with an IC50 value of 7 
µmol/L (2800 ng/ml). This concentration is ≥ 146× higher than the maximum free therapeutic 
concentration of 20 mg lenabasum twice-daily (BID) in humans, indicating a low liability for 
causing torsade de pointes (Redfern et al, 2003). In initial safety and tolerability studies, 
prolongations of QTc were observed using single electrocardiogram (ECGs); however, no QTc 
exceeded 500 msec (maximum QTc observed was 487 msec) and all were considered not 
clinically significant. In the SSc (JBT101-SSc-001) and CF (JBT101-CF-001) studies, triplet 
standardized ECGs with QT/QTc interval measurements showed no prolongation of QTc 
intervals or other significant ECG findings compared with placebo. QT/QTc intervals will be 
measured in this study. Convulsions consistent with CB1 effect on the brain have been observed 
in some non-clinical studies; however, lenabasum did not lower seizure threshold in a study done 
in rats specifically to evaluate the effect of lenabasum on seizure potential. No 
convulsions/seizures have been observed in any clinical studies done to date. Ataxia was 
observed at high doses in rats and mice and at ≥ 10 mg/kg/day in dogs where plasma exposures 
were approximately 7.6× higher than the anticipated maximum area under the curve (AUC) 
exposure achieved with lenabasum 20 mg BID (40 mg total daily dose). Ataxia has not been 
observed in humans. 
Lenabasum has been found to be well-tolerated in clinical studies conducted to date with only 
mild or moderate AEs related to lenabasum observed. Together, results from the preclinical 
safety, toxicology and pharmacokinetic (PK) studies, efficacy studies in animal models of 
disease, studies with human biomaterials, and safety and preliminary efficacy data in humans 
support a favorable benefit-risk profile of lenabasum.  These results support further study of 
lenabasum as a treatment for rare and serious inflammatory and fibrotic diseases with significant 
unmet medical need. 
Additional information about the known and expected benefits and risks and reasonably expected 
AEs of lenabasum may be found in the Investigator’s Brochure.  

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3. 
STUDY DESIGN 
3.1. 
Overall Design 
This is a Phase 3, multicenter, interventional, study designed to assess the efficacy and safety of 
lenabasum in subjects with DM. The study consists of two parts: Part A is a double-blind, 
placebo-controlled phase.  Part B is an optional OLE phase with a single treatment arm.  The 
overall design for this study is presented in Figure 1.  
Figure 1: 
Study Design for JBT101-DM-002 
 
Abbreviations: BID = twice daily, DB = double blind, OLE = open label extension, PC = placebo controlled 
3.1.1. 
Part A: Double-Blind, Placebo-Controlled Phase 
The initial plan is for approximately 150 dosed subjects to receive at least 1 dose of study 
product. The final number of subjects to be dosed will be decided after a blinded interim 
analysis. The timing and methods for the interim analysis will be outlined in the SAP. It is 
expected that approximately 200 subjects will be screened to dose 150 subjects.  
Subjects will be randomized to receive lenabasum 20 mg, lenabasum 5 mg, or placebo BID in a 
2:1:2 ratio. It is hypothesized that subjects receiving lenabasum will experience greater 
improvement in the TIS score at Week 28 compared to subjects receiving placebo.   
The total subject duration is approximately up to 60 weeks and includes the following: a 
screening visit (up to 4 weeks prior to Visit 1), up to a 52-week treatment period, and a Safety 
Follow-up Visit that will be conducted 4±1 weeks after the last visit. Subjects will be assessed 
for safety and efficacy parameters every 6 weeks except for Visit 2, which will occur 4 weeks 
after Visit 1, for a total of up to 10 treatment visits. Study personnel will contact subjects by 
telephone about halfway between Visit 9 and Visit 10 (Week 49 ± 1) to assess compliance, 
safety and overall status of DM, if applicable.   
A subject’s corticosteroid or other immunosuppressant treatments may be reduced if the 
investigator determines that clinical improvement in the subject’s DM has occurred and a 
reduction is warranted. It is recommended that a reduction in corticosteroid or 
immunosuppressant treatment should not occur prior to Visit 4 or after Visit 8. A preferred 
schedule for reduction is provided in Section 5.5.1 of the protocol.   

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3.1.2. 
Part B: Optional Open-label Extension  
Upon completing Part A (Visit 10), at the investigator’s discretion, consenting subjects may 
directly rollover into the optional OLE Phase (Part B). All subjects in the OLE will receive 
lenabasum 20 mg BID (see Table 4). 
Subjects will continue their standard of care treatment as in Part A. Subject’s corticosteroid or 
other immunosuppressant treatments may be reduced during this study if the investigator 
determines that clinical improvement in the subject’s dermatomyositis has occurred and a 
reduction is warranted. A preferred schedule for reduction of corticosteroid is provided in 
Section 5.5.1.  
The OLE may be extended beyond 1 year. Sites will be notified by an administrative memo as to 
any extension and will inform their EC/IRB. The design of an extended OLE will follow the 
same design and procedures as described in Table 4. At the investigator’s discretion, consenting 
subjects will rollover at the conclusion of Visit B8. The extension visits will be captured in the 
electronic data capture (EDC) as C1-C8 respectively.  
Subjects who discontinue the study at any stage and for any reason will be encouraged to 
complete the procedures described in the Early Termination (ET) Visit as well as complete the 
Safety Follow-up Visit 4 ± 1 weeks later.   
The same efficacy and safety parameters described as primary and secondary objective for Part 
A will be evaluated in Part B as described in the SAP.  
The results of Part B are expected to be analyzed after Part A results have been completed and 
will be reported as either an addendum to the clinical study report (CSR) or as a separate CSR.  
3.1.3. 
Study JBT101-LTS-001: 2-year Observational Safety Follow-up 
Subjects who participated in Part A but are ineligible for the OLE (e.g., completed Part A and  
declined participation in the OLE, or subjects who discontinued from Part A for whatever 
reason), will be offered the opportunity to participate in a separate 2-year non-interventional 
safety surveillance study (Study JBT101-LTS-001). 
3.2. 
Scientific Rationale for Study Design 
3.2.1. 
Part A: Double-blind, Placebo-controlled Phase 
In Part A, a double-blind, randomized, placebo-controlled design will be used. Part A will 
include up to 52-weeks of treatment to facilitate an unbiased assessment of the efficacy, safety 
and tolerability of lenabasum in the treatment of DM (see Table 3). Twenty-eight weeks 
treatment is expected to be sufficient to demonstrate long-term safety and efficacy of lenabasum 
compared to placebo, to support long-term use of lenabasum and 52-weeks treatment and OLE 
are expected to provide further evidence of long-term-safety and efficacy. 
Subjects will be allowed to continue their current treatment, which will reduce the risk of disease 
flare precipitated by discontinuation of medication to meet entry criteria.  
The primary endpoint chosen for this study is the TIS (Aggarwal et al., 2017) at 28 weeks. 
Because of heterogeneity in the organ-involvement in DM, organ-specific efficacy outcome does 
not reflect the extent of disease in DM. The TIS score is based on 6 core measures: patient and 

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physician global activity on a 10-cm VAS, muscle strength measured by MMT, physical 
function measured by the HAQ, extramuscular global activity (EMGA) measured by the 
physician on a 10-cm VAS, and the most abnormal serum muscle enzyme.  Absolute value and 
change from Baseline in each core set measure will be provided to support the TIS assessment. 
The patients with DM targeted for inclusion in this study are those who reflect the totality of DM 
manifestations, making TIS a reasonable primary endpoint.  Definition of Improvement (DOI), 
Investigator Global Assessment (IGA) scale of skin activity, TIS ≥ 40 (at least moderate 
improvement), TIS in subjects receiving any immunosuppressant medication for > 1 year, TIS at 
Week 52, and Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI) activity 
score are selected as secondary efficacy outcomes that provide additional measures of 
improvement on various aspects of DM disease. Change in corticosteroid dose and other 
immunosuppressives will be captured as a tertiary efficacy outcome, because long term side 
effects from systemic corticosteroids and other immunosuppressant medications pose a major 
safety risk to patients.  
3.2.2. 
Part B: Open-Label Extension 
In Part B, all subjects will receive open-label lenabasum 20 mg BID.  Similar efficacy and safety 
assessments will be performed at regularly scheduled visits (see Table 4) based on the scientific 
rationale for Part A. 
3.3. 
Justification of Dose 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
  
 
 
 
 
 
 
  
 
 
 
 
 
  
 
 
 
 
 
  
  
 
 
 
 
 
 
 
 
 
 
 
  
 
  
 
  
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
  
 
 
p
  
 
 
 
 
  
 
 
 
 
  
 
 
 
 
 
 
 
 
 
  
 
  
  
 
 
  
 
 
 
 
 
 
 
 
  
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
  
 
 
 
 

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4. 
STUDY POPULATION 
4.1. 
Inclusion Criteria 
Subjects must meet ALL of the following criteria to be eligible for the study:  
1. Able to understand and voluntarily sign the informed consent 
2. Male or female ≥ 18 years of age at the time of signing the informed consent 
3. Fulfill one of the following criteria for DM:  
a. Bohan and Peter’s criteria for probable or definite DM (Bohan and Peter, 1975a; 
Bohan and Peter 1975b)  
b. ACR/EULAR criteria (Lundberg et al, 2017)  
4. Subject has active DM as determined by the investigator 
5. Disease activity/severity fulfils one of the following three criteria: 
i. 
MDGA ≥ 3 cm (0-10 cm scale) and MMT-8 score ≤ 142 (out of 150 total possible) 
ii. Sum of MDGA, PtGA and EMGA VAS scores is ≥ 10 cm (all scales individually on 
0-10 cm scale) 
iii. MDGA ≥ 3 cm and CDASI activity score of >14 
6. Stable doses of immunosuppressive medications for DM as defined by: 
a. Unchanged dose of oral corticosteroids ≤ 20 mg per day prednisone or equivalent for 
≥ 4 weeks before Visit 1 
b. Unchanged dose of immunosuppressive medications other than oral corticosteroids 
for ≥ 8 weeks before Screening 
7. Willing to not start or stop any immunosuppressive medications for DM from Screening 
through end of study, unless a change is part of the protocol or considered in the subject’s 
best medical interest by the site investigator or another physician who has primary 
responsibility for treating the subject’s DM. 
8. Willing to not use any cannabinoids, including recreational marijuana, medical marijuana 
and other prescription cannabinoids from Screening through end of study. 
9. Able to adhere to the study visit schedule and other protocol requirements and follow 
study restrictions. 
10. Women of childbearing potential (WOCBP) must not be pregnant or breastfeeding and 
they or their male sexual partner must be using at least one acceptable method of 
contraception (see Appendix 1) for at least 4 weeks before Visit 1 and be willing to 
continue its use for at least 4 weeks after discontinuation of study product. 
11. Male subjects must be willing to follow acceptable contraceptive requirements (see 
Appendix 1) and should not get anyone pregnant while they are taking the study product 
or within 4 weeks after taking the last dose of the study product, during which time 
period they or their female sexual partner must be willing to use at least one 
recommended method of contraception. 
 

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6. Any medical, psychiatric or substance abuse condition, concurrent medical therapies, or 
abnormal laboratory values that in the opinion of the site investigator may put the subject 
at greater safety risk, influence response to study product, or interfere with study 
assessments. 
7. Subjects who have been accommodated in an institution as a result of official or judicial 
decision. 
When there is doubt as to subject eligibility, the investigator or qualified designee should 
discuss a subject’s eligibility with the Medical Monitor.  
4.3. 
Screen Failures 
Screen failures are defined as subjects who consent to participate in the clinical trial but are not 
subsequently randomized to the study intervention or entered in the study following Screening 
Visit. 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 (CONSORT) 
publishing requirements, and to respond to queries from regulatory authorities. Minimal 
information includes demography, screen failure details, eligibility criteria, and any serious 
adverse event(s) (SAE). 
Individuals who fail to meet eligibility criteria at Screening may have repeat screening 
evaluations done without being considered screen failed as long as eligibility criteria are met 
within 42 days. If the interval between the Screening Visit and Visit 1 is longer than 28 days but 
≤ 42 days because of repeat screening evaluations, then repeat metabolic panel and hematology 
laboratory testing must be done within 28 days of Visit 1 and results reviewed by the investigator 
before dosing at Visit 1. Ideally, any repeat laboratory screening tests will be done at the central 
laboratory. If returning to the clinic for repeat screening laboratory tests would cause major 
inconvenience for the subject, for example because of long distance travel, repeat laboratory tests 
can be done at a local laboratory only if results are made available to the investigator for review 
before dosing. 
If the patient did not meet eligibility criteria, despite retesting, within 42 days, the patient will be 
considered a screen fail.   
Individuals who are screen failures may be rescreened once again at the discretion of the 
investigator. The subject is eligible for enrollment if the results of repeated screening 
assessments meet eligibility criteria.   

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Figure 2: 
Rescreening of Subjects  
 
Screen failed patients may be rescreened once again at the discretion of the Investigator. 
4.4. 
Subjects Randomized Erroneously 
Subjects who do not meet all of the inclusion criteria or meet any exclusion criteria should not be 
randomized. If a subject is randomized in error and the error is recognized before dosing, the 
subject should not be dosed with study product. If the error is recognized after dosing, 
discontinuation of dosing as outlined in outlined in Section 6 should be followed. 
4.5. 
Strategies for Recruitment and Retention 
The target enrollment (i.e., randomized and dosed) for this study is approximately 150 subjects. 
Most subjects will be recruited from clinics run by the investigators or at which the investigators 
participate. It is preferred that enrolled subjects have been followed in the investigator’s clinic 
prior to study start. Advertisement for subjects outside the investigator’s site is not preferred, 
although it is allowed.  
Target screening of approximately 200 subjects (to achieve about 150 subjects randomized and 
dosed) is expected to take place over approximately 24 months and may be extended depending 
on enrollment rate. Number of subjects screened may be adjusted depending upon the screen 
failure rate, to ensure approximately 150 dosed subjects (mITT population). The number of 
subjects dosed may be adjusted depending on blinded interim analysis as noted in Section 9.4.9.  
To encourage retention in the study, every effort will be made to be respectful of the subject’s 
time. The total time required from the subject for study visits will vary with the efficiency of 
each site and is expected to be about 4-5 hours for Visit 1, 0.5-1 hour for visits when efficacy 
assessments are not done, and 1-2 hours for visits when efficacy assessments are done. 
Subjects will be encouraged to stay in the study at each visit by study personnel and reminded of 
the date and time of their next visit. If the subject agrees, e-mail or text message reminders of 
visits may be sent. 

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To reduce missing data, subjects who discontinue study product for reasons of safety or 
tolerability will be asked to remain in the study and return for evaluations on Visit 4, Visit 6, 
Visit 8 (if they have not already had Visit 4, 6, and 8) and Visit 10 unless the subject withdraws 
consent or is lost to follow-up. These off-treatment safety and efficacy data will be included in 
data analyses. 
4.6. 
Women, Minorities, and Children (Special Populations) 
Women and minorities are allowed in the study. Prevalence rates of DM are higher in women 
than in men (approximately 2:1 ratio reported), and more female than male subjects are expected 
in the study. 

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• Subjects who take more than the prescribed dose of study product should be 
instructed to contact site staff immediately and to seek emergency medical care, if 
needed 
Instructions for Missed Dosing: 
• If a dose is missed, it should be taken as soon as possible on the same day 
• If a dose is missed and it is time for the next dose, take the next dose as regularly 
scheduled and do not take a make-up dose 
• If dosing is missed for the entire day, it should not be made up and take the regularly 
scheduled dose for the following day 
Instructions for Dosing before Study Visits (Part A PK Visits ONLY – Visits 2, 4, 6 and 10): 
• The site staff should instruct the subject to hold the dose of study product on the 
morning of the visit or take the dose earlier on that morning if necessary to ensure 
that the blood sample will be drawn within an 8- to 16-hour window. Instructions on 
whether the subject should take or hold dosing on the morning of Visits 2, 4, 6, and 
10 requires the site staff to know when the subject typically takes the study product 
and the likely time of blood drawing at the visit.  
• The time of last dose of study product should be recorded at each visit. If a subject 
held the morning dose of study product, the subject may take that dose of study 
product as convenient after blood for plasma concentration and metabolites of 
lenabasum is drawn. 
• Every effort should be made to remind the subject of this requirement 1-3 days prior 
to the scheduled visit.  
5.2. 
Preparation/Handling/Storage/Accountability 
5.2.1. 
Acquisition and Accountability 
The study product will be dispensed from the site pharmacy or the investigator’s storage cabinet 
in a blinded fashion upon request from the investigator or designee. In Part A, the study product 
will be dispensed to the subject in accordance with the study product bottle/kit assignments 
raised by the interactive web-based randomized system (IWRS) and will be based on treatment 
assignment for that individual. In Part B, all subjects will receive the same treatment of 
lenabasum 20 mg.   
No more than a 6-week (+2) supply of study product plus packaged overage in the bottle(s) may 
be provided to the subject at time of dispensing in Part A and 8-week (+2) in Part B. Detailed 
instructions will be in a manual provided to the site by Corbus. A repository of study product 
will be held at distribution depots. Study product will be distributed to the site pharmacy or 
investigator by express mail with tracking. 
Depending upon the arrangements at the individual site, either the investigator or designee or the 
designated site pharmacist is responsible for maintaining accountability for the receipt, 
dispensing, and return of all study medication. Procedures for tracking shipment, receipt, 

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distribution, and collection of unused study product will be in a manual provided by Corbus to 
each site. 
5.2.2. 
Formulation, Appearance, Packaging, and Labeling 
The formulation of lenabasum used for clinical supply is powder-in-capsules (PIC). Details of 
lenabasum and placebo study products are provided below: 
• Lenabasum: The preparation of lenabasum clinical drug product is presented as size 
no. 2 white opaque hard gelatin capsules containing neat Drug Substance at either 20 
mg or 5 mg of lenabasum with a purity ≥ 98.5%. There are no other excipients 
contained in lenabasum capsules. 
• Placebo: The preparation of placebo is presented as identical size no. 2 white opaque 
hard gelatin capsules of lenabasum and contains 20 mg of a powder blend composed 
of microcrystalline cellulose and magnesium stearate. Both excipients are commonly 
used together in the pharmaceutical industry as regular excipients. 
Lenabasum and placebo capsules will be packaged in the same type bottle with the same number 
of capsules in each bottle. All study product will have an expiry date that exceeds the last date 
when the study product will be administered to that subject. The bottles will be indistinguishable 
from each other in appearance. 
Lenabasum and placebo will be dispensed to study subjects in the original packaging with a label 
clearly indicating that the contents are for investigational purposes only. The label will be 
created according to each country’s specific requirements. Additional labels must not cover the 
caution label or the name of the manufacturer. 
5.2.3. 
Product Storage and Stability 
Both lenabasum and placebo are packaged in 35 capsules per bottle in 60 cc high density 
polyethylene bottles, with the oxygen scavenger, a child resistant cap and induction seal.  
Bottles of study product are to be stored at the site within the temperature range specified in the 
IP Manual (15  25°C) away from temperature and humidity extremes, and under conditions 
appropriate for small quantities of Controlled drugs Act Schedule 1 substances, where 
applicable. The receipt, security, and storage of study product will comply with the country and 
local legal and/or regulatory requirements for each participating investigator site.  Storage of 
study product including undispensed and returned (used and unused) study product will remain 
under these storage conditions until returned to Corbus or designee for destruction.  
The site pharmacist, investigator or designee will maintain accurate logs of drug shipments to 
ensure the appropriate amount of study product is kept on site and that it is used for research 
purposes only. He/she will perform drug accountability procedures such as checking drug 
shipments against the shipping contents form, maintaining a log of the amount of study product 
provided to individual subjects, and reconciling used and unused drug supply by subjects and the 
study unit. 
Any lost or damaged study product should be documented in the source documents and reported 
to Corbus and regulatory authorities, as required. 

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Subjects will be instructed to store study product at home within the temperature range specified 
in the IP Manual (15 to 25°C), away from temperature and humidity extremes, with the labeling 
and child-proof cap intact, in areas that are not accessible to children. All study product that is 
not ingested by study subjects must be returned to the site and disposed of according to 
instructions provided by Corbus in the Investigational Product Manual.  
5.2.4. 
Preparation 
Site personnel are not required to prepare study product.  
5.3. 
Measures to Minimize Bias: Randomization and Blinding 
Subjects will be randomized and dosed at a ratio of 2:1:2 to lenabasum 20 mg, lenabasum 5 mg, 
or placebo arms using an IWRS once a subject meets eligibility criteria and before first dose of 
study product.  
Randomization will be stratified based on the following:  
• Screening MMT-8 score (< 135 or ≥ 135) 
• Prednisone dose (≤ 10 mg or > 10 mg per day or equivalent) 
• Region (US vs. ex-US) 
The IWRS will be used for assignment of a unique Subject Identification number (SID), 
randomization to a treatment, and assignment of study product bottle numbers to each subject. A 
subject is considered randomized into the study upon randomization confirmation from the 
IWRS. 
A central randomization scheme will be used. Randomization does not require the subject’s 
presence at the site. The randomization steps are the following:  
• Before accessing the IWRS the investigator or designee should confirm the subject 
meets all eligibility criteria 
• The investigator or designee confirms the site and subject ID and that subject meets 
eligibility criteria within the IWRS 
• The IWRS randomizes the subject to a treatment (lenabasum or placebo) and assigns 
the study product bottle(s) to be provided to the subject 
Lenabasum and placebo capsules have similar physical appearance and will be packaged, labeled 
and handled so that subjects and study staff are not able to distinguish between the two. Identical 
assessments and procedures will be followed during the study for subjects assigned to lenabasum 
or placebo study group. 
Part A of this study is double-blinded and will remain blinded until all data entry and processing 
are complete and the database has been locked. Except for necessary unblinding (see Section 
5.3.1), all Corbus medical and clinical operations staff associated with this study, both internal 
Corbus staff and contract staff, including the Medical Monitor, project management, and site 
monitors, will remain blinded to treatment randomization until the database is closed (except for 
certain personnel detailed below). Study subjects and the study site staff including the 
investigator and any co-investigator who will do safety and clinical assessments, qualified 

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designees, study nurses, study coordinators, and pharmacists will be blinded to intervention 
groups, except in the case of necessary unblinding (see Section 5.3.1). The final unblinding of all 
study subjects will occur only after the database has been locked. If treatment allocation for a 
subject otherwise becomes known to the clinical site staff, the principal investigator must be 
notified immediately of the unblinding (but not of the treatment allocation), and the principal 
investigator will notify Corbus of the unblinding but not of the treatment allocation.  
Corbus clinical research pharmacy services and supply and logistics personnel will be unblinded 
to the study product randomization. They are required not to reveal randomization information to 
others, unless a formal unmasking of information for a given subject is undertaken for safety 
reasons. 
A limited number of contract laboratory personnel who will perform and interpret assays such as 
lenabasum concentrations may be unblinded during the study.  These results will be provided to 
the Medical Monitor and other clinical personnel associated with the study using dummy subject 
identifications until the database is locked. Certain data management, programming, external 
DMC biostatistician, pharmacokinetics, and pharmacovigilance personnel at or contracted by 
Corbus may be unblinded. These unblinded Corbus personnel will not be associated with the 
clinical conduct of the study and will not reveal to any clinical personnel involved in the study 
the treatment to which a subject is assigned. The DMC may request subjects be unblinded for 
evaluation during closed sessions.  
5.3.1. 
Unblinding Procedures During the Study 
To maintain the overall quality of data collected during the study, breaks in blinding during the 
conduct of the study should occur only in exceptional circumstances when knowledge of the 
actual treatment is essential for further management of the subject. Unblinding of the study 
product for an individual can be done during the study period in the case of: 
• Any AE where knowledge of the treatment assignment is necessary to treat the subject 
• A child accidentally takes the study product 
• Pregnancy of a subject in the study 
If the investigator decides that a safety concern warrants unblinding, the investigators will have 
24-hour access to an IWRS through which the code can be broken. Procedures for unblinding 
through the IWRS will be described in a manual supplied to the site. The investigator should 
make every effort to contact the sponsor before unblinding a subject’s treatment assignment 
unless this could delay emergency treatment of the subject. In all circumstances other than a 
medical emergency, unblinding will be done only after discussion with the Medical Monitor.   
Emergency treatment unblinding must be reported to the Medical Monitor immediately, and 
Corbus will be notified through the IWRS regarding the unblinding. When it is necessary to 
break the blind, the investigator must notify the EC/IRB as applicable.  
If a subject is unblinded, the subject will discontinue treatment with study product and will have 
either a routine scheduled visit if due or an unscheduled visit as soon as possible to evaluate the 
safety concern that prompted the unblinding and there will be no further efficacy assessments.  

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If unblinding is deemed necessary, the investigator should not disclose the treatment assignment 
to other study personnel until after database lock and disclosure of treatment assignment to all 
subjects. 
5.3.2. 
Unblinding Procedures at the End of Part A 
After Part A completion, when all data have been collected, all queries have been resolved, the 
DMC has had a final review of the safety data, and the database has been locked, the lead 
statistician will be authorized by Corbus to generate a request to the IWRS to unblind the 
treatment code for all subjects for purposes of data analyses.  
After the database has been locked and the blind has been broken for the study, the investigators 
will be notified by Corbus of individual subject treatment allocation. The investigators may then 
inform subjects of their blinded treatment allocation, if the subjects choose to know, and EC/IRB 
requirements for disclosure, if any, have been met. 
5.4. 
Study Intervention Compliance 
The number of capsules of study product returned to the site will be counted and recorded as a 
measure of subject compliance with treatment. 
5.5. 
Concomitant Therapy 
Doses of non-corticosteroid immunosuppressant medications should be stable for ≥ 8 weeks at 
screening. Doses of oral corticosteroids should be stable for ≥ 4 weeks at Visit 1. Examples of 
allowed background immunosuppressive agents include and are not limited to prednisone or 
other glucocorticoid medications, mycophenolate, methotrexate, azathioprine, cyclosporine, 
cyclophosphamide, intravenous gamma globulin, and monoclonal antibody treatments. If there is 
any question about use of concomitant immunosuppressant medications, the investigator should 
discuss eligibility with the Medical Monitor. 
Concomitant therapies taken for chronic treatment of pre-existing conditions may be continued 
during the study. It is preferred that these medications be stabilized before entry and continued 
wherever practical without variation of dose or regimen during the study. 
During the study, concomitant medications and new medications should be administered at the 
discretion of the investigator or treating physician to provide the subject with the best possible 
medical care. It is recommended that changes in ongoing treatments or introduction of new 
therapies are kept to a minimum to avoid confounding efficacy and safety evaluations. 
5.5.1. 
Guidelines for Reduction in Concurrent Immunosuppressant Medications 
including Corticosteroids 
For both Part A and Part B, doses of concurrent immunosuppressive medications including oral 
corticosteroids may be reduced during the study at the discretion of the investigator.  Appropriate 
reasons for reduction would be AEs or intolerance related to the immunosuppressant medication 
or clinical improvement in DM during the study. These general principles should be observed for 
dose reduction in immunosuppressant medications:  
• A reduction in immunosuppressant medications can be done at any time during the 
study for AEs or tolerability concerns related to that immunosuppressant medication. 

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5.5.2. 
Guidelines for New or Increased Dose of Immunosuppressive Medications or 
Rescue Treatment 
Eligibility criteria permit subjects enrolling in this study to receive treatment with stable doses of 
concomitant immunosuppressive medications except oral prednisone > 20 mg per day or 
equivalent at Visit 1. For Part A, the intent is that the subject remains on stable doses of any 
Baseline concomitant immunosuppressive medications through Visit 4 at Week 16 and then 
reduce dose according to the pre-specified schedule in Section 5.5.1 only if the subject meets 
reduction criteria. 
If the subject has worsened between Screening and Visit 1 and requires new or increased doses 
of immunosuppressive medications at the time of Visit 1, that subject should be discontinued 
from the study before randomization and if already randomized, should be discontinued before 
dosing.  
After Visit 1, and throughout the study, including Part B, if applicable, doses of current 
concomitant immunosuppressive medication(s) may be increased or new immunosuppressive 
medication(s) may be started under the following circumstances: 
• The subject requires a temporary increase in chronic corticosteroid dose for safety 
reasons to prevent adrenal insufficiency, for example, in the setting of acute 
concurrent illness or surgery. 
• The subject has a concurrent illness that requires new corticosteroid medication or an 
increase in corticosteroid dose, such as acute severe allergic reaction. 
• The subject has medically significant worsening in their DM, and the site investigator 
or other physician primarily responsible for treating the subject’s DM considers it in 
the subject’s best medical interest to treat the increase in DM signs or symptoms with 
new or increased doses of immunosuppressive medications. The reason(s) for this 
decision must be documented and any medically significant worsening of the disease 
should be reported as an AE.  
• If a subject has worsening of DM following reduction in immunosuppressive 
medication (Section 5.5.1), a higher dose of that immunosuppressive medication may 
be given again. 
As soon as practical and ideally before any increase in immunosuppressive medications, the site 
investigator should have a discussion with the Medical Monitor about the reasons for increase.  
Keeping the subject in the study is generally preferred over withdrawing the subject from the 
study, even when that subject requires rescue medication.  
5.5.3. 
Prohibited Medications During the Study 
• Any investigational agent within 30 days or 5 therapeutic half-lives of that agent, 
whichever is longer, before Visit 1 and throughout the study. 
• Any cannabinoid, including recreational marijuana, medicinal marijuana or other 
prescription cannabinoids are prohibited from Screening throughout the study. 

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6. 
DISCONTINUATION OF STUDY TREATMENT, SUBJECT 
WITHDRAWAL, AND EARLY TERMINATION  
6.1. 
Discontinuation of Study Treatment and Subject Withdrawal 
Subjects are free to withdraw from participation in the study at any time upon request.  
A subject will not receive any further study product if any of the following events occur:  
• Subject lost to follow-up 
• Withdrawal of consent for study participation 
• Subject decision to discontinue treatment  
• Pregnancy  
• Any serious or life-threatening AE probably or definitely-related to lenabasum 
• Any AE, which in the opinion of investigator, can jeopardize the safety of an 
individual subject 
• Subjects recognized as being treated despite being wrongly randomized (i.e., not 
meeting all eligibility criteria) 
• Other event(s) which in the opinion of the site investigator or Medical Monitor 
contraindicates further dosing such as, but not limited to, repeated failure to meet 
protocol requirements, significant concurrent illnesses or disease complications 
Subjects withdrawn for the above reasons, except lost to follow-up or withdrawn consent, will be 
asked to return to Visit 4, Visit 6, Visit 8 (if they have not already had Visit 4, 6, and 8), and 
Visit 10; Weeks 16, 28, 40 and 52, respectively. These subjects will not be required to but may 
undergo optional blood sampling, skin photography, or skin biopsies at the remaining visits if 
they had opted in previously.  
Subjects who are discontinued permanently from drug therapy due to an AE related to study 
product will be followed until resolution or stabilization of the event. Subjects who are 
withdrawn due to pregnancy, or partners of subjects who become pregnant, will require 
additional follow-up as outlined in Pregnancies, Section 8.2.7.8. 
Subjects who withdraw consent will be asked to complete the early termination (ET) visit; 
however, completion of the visit will not be mandated.  
A subject will be considered lost to follow-up if he/she does not respond to the following:  
• Three attempts at contacting the subjects (including phone calls, emails, or texts and a 
certified letter) from a member of the research staff over a period of up to a month; 
• A certified letter updating him/her on the study status. 
Documentation of the contact attempts and the certified letter should be filed with the subject’s 
source documents. 
 
 

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The reason for subject discontinuation or withdrawal from the study will be recorded in the 
eCRF. If the subject is discontinued from treatment due to an AE, the reason for discontinuation 
should be listed as due to an AE. The number of subjects screened may be adjusted to achieve 
the target number of subjects who receive at least 1 dose of study product. 
Study product will be stopped without tapering because abrupt discontinuation of lenabasum is 
not known to cause any harmful effects. All remaining study product will be returned to the 
study staff. 
6.2. 
Early Termination of Study  
This study (either or both Part A and/or Part B) may be suspended or prematurely terminated at 
the discretion of the Sponsor if there is sufficient reasonable cause. For example, any new 
information about the execution of the trial, that, in the opinion of the Sponsor, contraindicates 
further study entry and randomization of new subjects, such as unsatisfactory enrollment with 
respect to quantity or quality, insufficient adherence to protocol requirements, data that are not 
sufficiently complete and/or evaluable, falsification of records, or determination of futility. 
If any of the following events occur during enrollment, then study entry and randomization of 
new subjects into the study or rollover to Part B will be suspended until review of the event in 
question occurs by the DMC: 
• Death in any subject considered to be related to lenabasum 
• Two life-threatening clinical events judged to be probably- or definitely-related to 
lenabasum. NOTE: The term ‘life-threatening’ 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 
• Determination of unexpected, significant, or unacceptable risk to subjects that 
contradict dosing of additional subjects, in the opinion of the Corbus Chief Medical 
Officer 
Administration of study product may continue during the time of review in subjects who are 
already receiving study product in either Part A and/or Part B, based on the judgment of the 
Corbus Chief Medical Officer. 
An expedited and cumulative review of safety data and the circumstances of the event(s) in 
question will be conducted by the DMC, with additional external expertise as needed, to make 
recommendations to the Sponsor whether study entry/randomization and dosing can resume or 
should be discontinued, whether the protocol should be modified, or whether the study should be 
discontinued permanently. Upon consideration of a cumulative review of safety and other data, 
the study may be discontinued permanently by the Sponsor. 
Written notification, documenting the reason for study suspension or termination, will be 
provided by the Sponsor to the site investigators and relevant regulatory agencies. If the study is 
suspended or prematurely terminated, the site investigators will promptly inform their site 
IRB/EC and will provide the reason(s) for the suspension or termination. Review and approval 
by the reviewing IRB/IEC at each site may be required for resumption of the study in the event 
the study is interrupted.  

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7. 
SCHEDULE OF ASSESSMENTS AND STUDY VISITS  
7.1. 
Assessments 

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d Systolic and diastolic BP will be measured with the subject supine for at least 5 minutes.  The same arm should be used for the measurement throughout the study as much as 
possible.  Pulse and respiration will also be measured with the subject supine for at least 5 minutes.  Body temperature will be measured on the skin or in the mouth. 
e Weight will be measured with coats, jacket, and footwear removed. 
f Standing height will be measured with footwear removed. 
g Full physical examination includes the following assessments: alertness and orientation, general appearance, skin, head, eyes, ears, nose, and throat, lungs, heart, abdomen, 
musculoskeletal examination, and lymph nodes. Breast and genitourinary examinations are not required.   
h Brief physical examination includes the following assessments: skin, lung, heart, abdomen, and any other area as indicated by changes in medical history. 
i Applicable for women ≤ 55 years of age with no menses for ≥ 1 year. 
j Refer to Appendix 1 for the criteria for determining reproductive potential and acceptable methods of contraception. 
k AE monitoring should begin at subject consent. 
l 12-lead ECG with QT/QTc intervals should be recorded with the subject in a rested supine position ≥ 10 minutes before the test.  
m Study personnel will be required to contact subjects 3 ± 1 week after Visit 9. 
n To occur at or before Visit 1. 
o The first dose of study product on Visit 1 will be taken in clinic from the dispensed study product. Vital signs include blood pressure, pulse rate, respiratory rate, and temperature 
and will be measured pre-dose and 3.0 ± 0.5 hours after administration of first dose of study product at Visit 1 in the clinic. ECGs will be recorded pre-dose and 3.0 ± 0.5 hours 
after administration of first dose of study product in the clinic. 
p Study product will be dispensed for administration in WOCBP only if urine pregnancy test is negative.   
q Ideally, all patient-reported efficacy assessments should be completed before all other study procedures, in the order listed.  
r It is preferred that physician assessments of efficacy are performed in the order listed.  
s Metabolic panel includes glucose, urea nitrogen, creatinine, estimated glomerular filtration rate, blood urea nitrogen/creatinine, sodium, potassium, chloride, carbon dioxide, 
calcium, protein total, albumin, bilirubin total, alkaline phosphatase, aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH); AST, 
ALT and LDH are three of the five muscle enzymes comprising the TIS (see Section 8.1.2).  
t Urine dipstick for blood, protein, glucose 
u Pharmacokinetic blood samples will be collected at Visit 1 pre-dose and 3.0 ± 0.5 hours after administration of first dose of study product in the clinic. Time of administration of 
the first study dose and time of PK sample collection (blood draw for PK) should be recorded At Visits 2, 4, 6, and 10, PK blood samples will be collected once during the visit 
and time of most recent dose of study product and blood collection should be recorded. Time of the blood draw should be 8-16 hours after the last dose of the study product, 
which typically would have been taken at subject’s home the evening before the visit. 
v Five optional , 4 mm skin biopsies will be collected: two at Visit 1, two at Visit 4 and one at Visit 10. At Site 1001, subjects will have the option to consent to two 6 mm and 
three 4 mm biopsies (e.g., one 4 mm and one 6 mm at Visit 1; one 4 mm and one 6 mm at Visit 4, and one 4 mm at Visit 10). Skin biopsies will only be conducted at selected 
sites.  
W Subjects who rollover into Part B should sign an ICF by Visit 10 and preferably earlier than Visit 10, if possible.  
x The Safety Follow-up Visit is to occur 4±1 weeks after the last visit (V10/ET) and is to be completed by subjects who do not rollover into Part B.  
 
 

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7.2. 
Study Visits  
A detailed description of all study procedures is provided in Section 8.2. Ideally, all patient-
reported efficacy assessments should be completed before all other study procedures, in the order 
listed. It is preferred that physician assessments of efficacy are performed in the order listed.  
7.2.1. 
Part A 
7.2.1.1. 
Screening (up to 4 weeks before Visit 1) 
• Informed consent 
• Patient-reported efficacy assessments, with instruction/ training in instrument by 
study staff 
− PtGA 
− HAQ-DI 
− SF-36 
− PROMIS-29 Short Form 
− Patient VAS score for pain 
− FACIT-Fatigue Score 
− 5-D Itch Questionnaire 
− Skindex-29+3 
− EQ-5D questionnaire 
• Medical history (including a detailed history of DM) 
• Record concomitant medication(s) 
• AE monitoring 
• Contraceptive assessment and record of last menstrual period (LMP) for WOCBP 
• Height, which will be used throughout trial as Baseline 
• Vital signs (including blood pressure [BP], pulse rate, respiratory rate, and 
temperature) and weight 
• 12 lead ECG 
• Spirometry for FVC 
• Full physical examination  
• Physician assessments of efficacy  
− MMT-8 
− CDASI score 

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− IGA scale of skin activity 
− EMGA (10-cm VAS) 
− MDGA (10-cm VAS and Likert Scale) 
• Physician assessment of DM activity (see Appendix 5) 
• Laboratory tests:  
− HIV, HBV and HCV testing 
− FSH and LH (if applicable) 
− Serum β HCG for WOCBP 
− Complete blood count (CBC) with differential and platelets 
− Metabolic panel (includes ALT, AST, and LDH) 
− Creatine phosphokinase (CK) and aldolase 
• Verify eligibility criteria (including verification of DM) 
7.2.1.2. 
Randomization  
Randomization within IWRS will occur before or at Visit 1. The subject does not need to be 
present in clinic for randomization to occur. See Section 5.3 for additional details.  
7.2.1.3. 
Visit 1 (Day 1) 
Pre-dose:  
• Verify eligibility criteria (including verification of DM) 
• Patient-reported efficacy assessments  
− PtGA 
 HAQ-DI 
− SF-36 
− PROMIS-29 Short Form 
 Patient VAS score for pain 
− FACIT-Fatigue Score 
− 5-D Itch Questionnaire 
 Skindex-29+3 
− EQ-5D questionnaire 
• Record concomitant medication(s) 
• AE monitoring  
• Contraceptive assessment and record of LMP for WOCBP  

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• Vital signs (including BP, pulse rate, respiratory rate, and temperature) and weight  
• 12 lead ECG 
• Spirometry for FVC 
• Full physical examination 
• Physician assessments of efficacy 
− MMT-8 
− CDASI score 
− IGA scale of skin activity 
− EMGA (10-cm VAS) 
− MDGA (10-cm VAS and Likert Scale)  
• Laboratory tests 
− CBC with differential cell count and platelets  
− Metabolic panel (includes ALT, AST and LDH) 
− CK and aldolase 
− Blood biomarkers 
− Blood for flow cytometry (optional at selected sites) 
− Paxgene tube collection 
− Autoantibody measurements 
− Urine βhCG in WOCBP  
− Urine dipstick  
• Skin biopsies (optional at selected sites) 
• Skin photography (optional at selected sites) 
• Lenabasum plasma concentration and metabolite profiling 
• Dispense study product 
Dosing:  
• The first dose of study product will be administered in the clinic using dispensed 
study product.  
Post-dose (3 ± 0.5 hrs) 
• Vital signs (including BP, pulse rate, respiratory rate, and temperature) 
• 12 lead ECG 
• Lenabasum plasma concentration and metabolite profiling 

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7.2.1.4. 
Visit 2 (Week 4 ± 1) 
• Every effort should be made to remind the subject of dosing requirements for PK 
sampling (Section 5.1) 1-3 days prior to the scheduled visit 
• Patient-reported efficacy assessments 
− PtGA 
− HAQ-DI 
 SF-36 
− PROMIS-29 Short Form 
− Patient VAS score for pain 
 FACIT-Fatigue Score 
− 5-D Itch Questionnaire 
− Skindex-29+3 
 EQ-5D questionnaire  
• Collect and count capsules of returned study product  
• Record concomitant medication(s) 
• AE monitoring  
• Contraceptive assessment and record of LMP for WOCBP  
• Vital signs (including BP, pulse rate, respiratory rate, and temperature) and weight 
• 12 lead ECG 
• Brief physical examination 
• Physician assessments of efficacy 
− MMT-8 
− CDASI score 
− IGA scale of skin activity 
− EMGA (10-cm VAS) 
− MDGA (10-cm VAS and Likert Scale)   
• Laboratory tests 
− CBC with differential cell count and platelets  
− Metabolic panel (includes ALT, AST and LDH) 
− CK and aldolase 
− Urine βhCG in WOCBP  

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− Urine dipstick  
• Lenabasum plasma concentration and metabolite profiling 
• Dispense study product 
7.2.1.5. 
Visit 3, Visit 5, Visit 7, Visit 91 (Weeks 10, 22, 34, and 46) 
• Collect and count capsules of returned study product  
• Record concomitant medication(s) 
• AE monitoring  
• Contraceptive assessment and record of LMP for WOCBP  
• Vital signs (including BP, pulse rate, respiratory rate, and temperature) and weight 
• Brief physical examination  
• Laboratory tests 
 CBC with differential cell count and platelets  
− Metabolic panel  (includes ALT, AST and LDH) 
− Urine βhCG in WOCBP 
• Dispense study product  
7.2.1.6. 
Visit 4 (Week 16 ± 1) 
• Every effort should be made to remind the subject of dosing requirements for PK 
sampling (Section 5.1) 1-3 days prior to the scheduled visit 
• Patient-reported efficacy assessments 
− PtGA 
− HAQ-DI 
− SF-36 
− PROMIS-29 Short Form 
− Patient VAS score for pain 
 FACIT-Fatigue Score 
− 5-D Itch Questionnaire 
− Skindex-29+3 
 EQ-5D questionnaire   
• Patient Improvement Questionnaire for Subjects (see Appendix 4) 
 
1 Study personnel will be required to contact subjects 3±1 weeks after Visit 9 to assess compliance and safety.  
 

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• Collect and count capsules of returned study product  
• Record concomitant medication(s) 
• AE monitoring  
• Contraceptive assessment and record of LMP for WOCBP  
• Vital signs (including BP, pulse rate, respiratory rate, and temperature) and weight 
• Spirometry 
• Brief physical examination  
• Physician assessments of efficacy 
− MMT-8 
− CDASI score 
− IGA scale of skin activity 
− EMGA (10-cm VAS) 
− MDGA (10-cm VAS and Likert Scale)   
• Patient Improvement Questionnaire for Physicians (see Appendix 3) 
• Laboratory tests 
− CBC with differential cell count and platelets  
− Metabolic panel (includes ALT, AST, and LDH) 
− CK and aldolase 
− Urine βhCG in WOCBP 
• Skin biopsies (optional at selected sites) 
• Lenabasum plasma concentration and metabolite profiling 
• Dispense study product 
7.2.1.7. 
Visit 6 (Week 28 ± 1) 
• Every effort should be made to remind the subject of dosing requirements for PK 
sampling (Section 5.1) 1-3 days prior to the scheduled visit 
• Patient-reported efficacy assessments  
− PtGA 
− HAQ-DI 
− SF-36 
− PROMIS-29 Short Form 
− Patient VAS score for pain 

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− FACIT-Fatigue Score 
− 5-D Itch Questionnaire 
− Skindex-29+3 
− EQ-5D questionnaire  
• Patient Improvement Questionnaire for Subjects (see Appendix 4) 
• Collect and count capsules of returned study product  
• Record concomitant medication(s) 
• AE monitoring  
• Contraceptive assessment and record of LMP for WOCBP  
• Vital signs (including BP, pulse rate, respiratory rate, and temperature) and weight 
• 12 lead ECG 
• Spirometry 
• Brief physical examination  
• Physician assessments of efficacy 
− MMT-8 
− CDASI score 
− IGA scale of skin activity 
− EMGA (10-cm VAS) 
− MDGA (10-cm VAS and Likert Scale)   
• Patient Improvement Questionnaire for Physicians (see Appendix 3) 
• Laboratory tests 
− CBC with differential cell count and platelets  
− Metabolic panel (includes ALT, AST, and LDH) 
− CK and aldolase 
− Blood biomarkers 
− Blood for flow cytometry (optional at selected sites) 
− Urine dipstick 
− Urine βhCG in WOCBP 
• Lenabasum plasma concentration and metabolite profiling 
• Dispense study product 

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7.2.1.8. 
Visit 8 (Week 40 ± 1) 
• Patient-reported efficacy assessments 
 PtGA 
− HAQ-DI 
− SF-36 
 PROMIS-29 Short Form 
− Patient VAS score for pain 
− FACIT-Fatigue Score 
 5-D Itch Questionnaire 
− Skindex-29+3 
− EQ-5D questionnaire   
• Collect and count capsules of returned study product  
• Record concomitant medication(s) 
• AE monitoring  
• Contraceptive assessment and record of LMP for WOCBP  
• Vital signs (including BP, pulse rate, respiratory rate, and temperature) and weight 
• Brief physical examination 
• Physician assessments of efficacy 
− MMT-8 
− CDASI score 
 IGA scale of skin activity 
− EMGA (10-cm VAS) 
− MDGA (10-cm VAS and Likert Scale)   
• Laboratory tests 
− CBC with differential cell count and platelets  
− Metabolic panel (includes ALT, AST, and LDH) 
− CK and aldolase 
− Urine βhCG in WOCBP 
• Dispense study product 

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7.2.1.9. 
Visit 102 (Week 52 ± 1) or Early Termination (ET) 
• Every effort should be made to remind the subject of dosing requirements for PK 
sampling (Section 5.1) 1-3 days prior to the scheduled visit 
• Patient-reported efficacy assessments 
− PtGA 
− HAQ-DI 
 SF-36 
− PROMIS-29 Short Form 
− Patient VAS score for pain 
 FACIT-Fatigue Score 
− 5-D Itch Questionnaire 
− Skindex-29+3 
 EQ-5D questionnaire   
• Patient Improvement Questionnaire for Subjects (see Appendix 4) 
• Collect and count capsules of returned study product  
• Record concomitant medication(s) 
• AE monitoring  
• Contraceptive assessment and record of LMP for WOCBP  
• Vital signs (including BP, pulse rate, respiratory rate, and temperature) and weight 
• 12 lead ECG 
• Spirometry 
• Full physical examination 
• Physician assessments of efficacy 
− MMT-8 
− CDASI score 
− IGA scale of skin activity 
− EMGA (10-cm VAS) 
− MDGA (10-cm VAS and Likert Scale)   
• Patient Improvement Questionnaire for Physicians (see Appendix 3) 
• Laboratory tests 
 
2 For subjects who rollover into the OLE, data collected at Part A, Visit 10, will also be used for Part B, Visit B1. 

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− CBC with differential cell count and platelets  
− Metabolic panel (includes ALT, AST, and LDH) 
− CK and aldolase 
− Blood biomarkers 
− Blood for flow cytometry (optional at selected sites) 
− Paxgene tube collection 
− Autoantibody measurements 
− Urine βhCG in WOCBP  
− Urine dipstick  
• Skin biopsies (optional at selected sites) 
• Skin photography (optional at selected sites) 
• Lenabasum plasma concentration and metabolite profiling 
• Informed Consent for Part B3 
7.2.2. 
Part B 
7.2.2.1. 
Visit B1 (Day B1) 
• For subjects who rollover into the OLE, data collected at Part A, Visit 10 (see 
Section 7.2.1.9), will also be used for Part B, Visit B1. 
• Informed Consent for Part B3 
• Dispense study product  
7.2.2.2. 
Visit B2, Visit B4, and Visit B6 (Weeks 4, 20, and 36) 
• Patient-reported efficacy assessments 
− PtGA 
− HAQ-DI 
− SF-36 
− PROMIS-29 Short Form 
− Patient VAS score for pain 
− FACIT-Fatigue Score 
− 5-D Itch Questionnaire 
− Skindex-29+3 
 
3 Subjects who rollover into Part B should sign an ICF by Visit 10 in Part A and preferably earlier than Visit 10, if 
possible.  

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− EQ-5D questionnaire   
• Collect and count capsules of returned study product  
• Record concomitant medication(s) 
• AE monitoring  
• Contraceptive assessment and record of LMP for WOCBP  
• Vital signs (including BP, pulse rate, respiratory rate, and temperature) and weight 
• Spirometry 
• Brief physical examination  
• Physician assessments of efficacy 
− MMT-8 
− CDASI score 
− IGA scale of skin activity 
− EMGA (10-cm VAS) 
− MDGA (10-cm VAS and Likert Scale)   
• Laboratory tests 
− CBC with differential cell count and platelets  
− Metabolic panel (includes ALT, AST, and LDH) 
− CK and aldolase 
− Urine βhCG in WOCBP 
− Urine dipstick 
• Dispense study product 
7.2.2.3. 
Visit B3, Visit B5, and Visit B7 (Weeks 12, 28, and 44) 
• Patient-reported efficacy assessments 
− PtGA 
− HAQ-DI 
− SF-36 
− PROMIS-29 Short Form 
− Patient VAS score for pain 
− FACIT-Fatigue Score 
− 5-D Itch Questionnaire 
− Skindex-29+3 

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− EQ-5D questionnaire   
• Collect and count capsules of returned study product  
• Record concomitant medication(s) 
• AE monitoring  
• Contraceptive assessment and record of LMP for WOCBP  
• Vital signs (including BP, pulse rate, respiratory rate, and temperature) and weight 
• Brief physical examination  
• Physician assessments of efficacy 
− MMT-8 
− CDASI score 
− IGA scale of skin activity 
− EMGA (10-cm VAS) 
− MDGA (10-cm VAS and Likert Scale)   
• Dispense study product 
Additional Procedures for Visit B5 ONLY 
− 12 lead ECG 
− Blood Biomarkers 
7.2.2.4. 
Visit B8 (Week 52) or Early Termination (ET) 
• Patient-reported efficacy assessments 
− PtGA 
− HAQ-DI 
− SF-36 
− PROMIS-29 Short Form 
− Patient VAS score for pain 
− FACIT-Fatigue Score 
− 5-D Itch Questionnaire 
− Skindex-29+3 
− EQ-5D questionnaire   
• Collect and count capsules of returned study product  
• Record concomitant medication(s) 
• AE monitoring  

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• Contraceptive assessment and record of LMP for WOCBP  
• Vital signs (including BP, pulse rate, respiratory rate, and temperature) and weight 
• 12 lead ECG 
• Spirometry 
• Full physical examination 
• Physician assessments of efficacy 
− MMT-8 
− CDASI score 
− IGA scale of skin activity 
− EMGA (10-cm VAS) 
− MDGA (10-cm VAS and Likert Scale)   
• Laboratory tests 
− CBC with differential cell count and platelets  
− Metabolic panel (includes ALT, AST, and LDH) 
− CK and aldolase 
− Urine βhCG in WOCBP 
− Urine dipstick 
− Blood biomarkers 
− Autoantibody measurements  
7.2.3. 
Safety Follow-up (4 ± 1 Weeks after last visit) 
Part A: The Safety Follow-up Visit is to occur 4±1 weeks after the last visit (Visit 10/ET) and is 
to be completed by subjects who do not rollover into Part B. 
Part B: The Safety Follow-up Visit is to occur 4 ± 1 weeks after the last visit (Visit B8 or Visit 
C8 if OLE is extended). Subjects who discontinue at any stage and for any reason will be 
encouraged to complete the Safety Follow-up Visit 4 ± 1 weeks after the ET Visit.   
Procedures for Safety Follow-up include:  
• Record concomitant medication(s) 
• AE monitoring  
• Contraceptive assessment and record of LMP for WOCBP  
• Vital signs (including BP, pulse rate, respiratory rate, and temperature) and weight 
• Brief physical examination  
• Laboratory tests 

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− CBC with differential cell count and platelets  
− Metabolic panel  (includes ALT, AST and LDH) 
− Urine βhCG in WOCBP 
7.2.4. 
Unscheduled Visit 
Unscheduled visits may be necessary to assess the subject for safety purposes. In this case, the 
following evaluations should be obtained, at a minimum: 
• AE monitoring 
• Record concomitant medications 
• Vital signs 
• Medical history as relevant to the reason for the unscheduled visit 
• Physical examination as relevant to the reason for the unscheduled visit 
• Laboratory tests as relevant to the reason for the unscheduled visit 
7.2.5. 
End of Study  
End of Study is defined as the date of Last Patient Last Visit where the final study subject is 
examined or receives an intervention for the purpose of data collection pertaining to primary and 
secondary outcome measures and adverse events, regardless of whether the study concluded 
according to the pre-specified protocol or was terminated. Section 6.2 details the events that 
would lead to study suspension or premature termination by Corbus. 

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8. 
STUDY ASSESSMENTS AND PROCEDURES  
Planned time points for all study procedures are provided in the schedule of assessments (SOA) 
in Section 7.1.    
8.1. 
Efficacy Assessments 
8.1.1. 
Training in Efficacy Assessments 
Physicians or a designated health care professional will be trained in the performance of all 
physician assessments of efficacy.  It is expected that the same individual will perform the 
physician assessments of efficacy at all visits, except in uncommon circumstances.  There is a 2-
week window for each study visit starting with Visit 2 to facilitated scheduling to allow for 
consistency in the assessor of efficacy outcomes.  In general, it is preferred that a given visit be 
slightly delayed to allow for the same individual to assess efficacy outcomes throughout the 
study, rather than have a different assessor. This is particularly important for visits when TIS is 
being evaluated (see Table 3 and Table 4). 
Subjects will be trained in the questionnaires used to assess patient-reported efficacy outcomes.  
This training will be done at Screening, so subjects can become familiar with the instruments 
prior to establishing Baseline values at Visit 1.  Starting with Visit 1, it is expected that patient-
reported efficacy assessments should be completed independent of input from study staff. 
Study staff will be trained in the performance of spirometry using centrally supplied equipment. 
It is preferred that the same individual perform spirometry at each visit for a given subject, as 
practicable. 
All efficacy assessments for the TIS will be calculated centrally. 
8.1.2. 
Total Improvement Score (TIS) 
Efficacy will be assessed using the 2016 ACR/EULAR Myositis Response Criteria Total 
Improvement Score, comparing the change from Baseline between lenabasum and placebo 
groups.  
Myositis response criteria were developed for both juvenile and adult populations and are based 
on a 0  100 scale. Six core measures are used to calculate the TIS (Aggarwal et al., 2017). 
Higher scores indicate better improvement in myositis. 
The six measures that comprise the TIS are summarized below:   
• Physician Global Activity (MDGA): An assessment of overall global disease activity by 
the physician will be done using a 10-cm VAS.  The Physician Assessments should 
ideally be done by the same investigator. The physician should refer to subject’s MDGA 
score from the previous visit to ensure consistency in rating.  
• Patient Global Activity (PtGA): An assessment of overall global disease activity by the 
patient will be done using a 10-cm VAS.  
• Manual Muscle Testing-8 (MMT-8): For MMT assessment, a MMT that assesses 
strength in 8 muscle groups (MMT-8) will be used. Strength in 8 muscle groups will be 
assessed on a 0  10 point scale (see Table 5) and recorded.  Strength in the following 7 

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• Extramuscular Global Activity (EMGA): The EMGA encompasses an overall 
evaluation for the disease activity in all the extramuscular organ systems and excludes 
muscle disease activity. EMGA will be assessed by drawing a vertical mark on a 0-10cm 
VAS scale. Anchored at each end of the 10-cm VAS are the descriptors “absent” and 
“maximum.”   
• Muscle Enzymes: The serum activities of the following muscle-associated enzymes will 
be assessed: the transaminases (ALT, AST), LDH, CK, and aldolase. The AST, ALT and 
LDH values will be done as part of the metabolic panel and CK and aldolase will be 
measured as additional muscle enzymes.  The most abnormal (by percentage) muscle 
enzyme at Baseline will be used in calculations of TIS.  All muscle enzymes will be done 
at a central laboratory.   
Please see Appendix 6 for algorithm to calculate TIS (Aggarwal et al, 2017). 
Because TIS is a composite score, absolute values and change from Baseline in each core set 
measure will be presented to support the primary efficacy endpoint. 
8.1.3. 
Definition of Improvement (DOI) 
The definition of improvement (DOI) (Oddis et al, 2013) is ≥ 20% improvement in 3 of any 6 
core set measures (same as used to determine the TIS), with no more than 2 core set measures 
worsening by ≥ 25%. For DOI to be achieved, the MMT-8 cannot worsen by ≥ 25%. For 
improvement in muscle enzymes to contribute to DOI, the muscle enzyme value must be greater 
than the upper limit of normal at Baseline. For worsening in muscle enzymes to contribute to the 
DOI, the muscle enzyme value must be greater than the upper limit of normal at the time of 
worsening. 
8.1.4. 
Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI) Score 
CDASI is a validated outcome measure that systematically quantifies cutaneous DM disease 
activity and damage (Klein et al, 2007; Yassaee et al, 2010). In the CDASI, DM skin disease 
activity is evaluated based on the physician's/qualified health personnel evaluation of erythema, 
scale, and erosion or ulceration at fifteen anatomic locations as well as alopecia, Gottron’s sign 
or papules on the hands, and periungual changes. Damage is evaluated based on poikiloderma 
and calcinosis at fifteen anatomic locations as well as Gottron’s sign.  
8.1.5. 
Investigator Global Assessment (IGA) scale of skin activity  
The IGA is a 5-point scale to evaluate overall skin disease by the investigator. Skin will be 
assessed as clear, almost clear, mild, moderate, or severe based on the overall description of each 
category as provided in Appendix 2.  
8.1.6. 
Short-Form-36 (SF-36) 
The Short Form 36-question health survey (SF-36) is a widely used tool that assesses the global 
medical quality of life, functional health, and well-being of general and specific populations. The 
SF-36 is comprised of 36 questions that cover the following 8 health concepts: physical 
functioning, bodily pain, role limitations due to physical health problems, role limitations due to 

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personal or emotional problems, emotional well-being, social functioning, energy/fatigue, and 
general health perceptions. 
8.1.7. 
Corticosteroid Dose 
Corticosteroids are commonly prescribed for the treatment of signs and symptoms of DM. 
Corticosteroid dose will be recorded as a concomitant medication, with start and stop dates.  
Change from Baseline in corticosteroid dose will be compared between the lenabasum 20 mg 
BID and placebo groups and the lenabasum 5 mg BID and placebo groups (see Section 9.4.3).   
8.1.8. 
Forced Vital Capacity  
Spirometry to measure FVC (actual and % predicted values) will be done using equipment 
supplied by the Sponsor. Study staff will be trained in the proper use of the spirometry 
equipment. As possible, the same operator should record spirometry for a given subject. FVC 
values will be measured and calculated in compliance with American Thoracic Society standards 
for spirometry (Miller et al, 2005).  Hankinson’s reference values (Hankinson et al, 2010) will be 
used to determine FVC percent prediction with additional correction for Asian subjects. 
8.1.9. 
Physician Global Activity (MDGA) – Likert Scale  
A second assessment of overall global disease activity by the physician will be done with a 5-
point Likert scale that uses the following scoring: 0 = None; 1 = Mild; 2 = Moderate; 3 = Severe; 
4 = Extremely severe. 
8.1.10. 
Patient Improvement Questionnaire for Physicians 
A brief questionnaire (see Appendix 3) will be administered that will determine overall 
improvement with treatment in the investigator’s judgment.  
8.1.11. 
Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue score 
The FACIT-F score is a 13-item patient-reported questionnaire that assesses tiredness, weakness, 
and difficulty conducting everyday activities due to fatigue in the last 7 days (Butt et al, 2013). 
Items are scored on a 5-point scale (0 = not at all, 4 = very much). All items except item 7 and 8 
are reverse-scored before item scores are summed to obtain a total score (range 0-52). A higher 
score indicates less fatigue. The FACIT fatigue tool has been previously validated in a study by 
Chandran et al, 2007. 
8.1.12. 
5-Dimension (5-D) Itch Score 
The 5-D Itch scale is a validated patient-reported assessment of itch in skin diseases (Elman et al, 
2010). It is a brief, multidimensional questionnaire with five dimensions of itch - degree, 
duration, direction, disability and distribution. The period of recall is 2 weeks. Single-item 
domain scores range from 1-5. The scores of each domain are summed to obtain a total 5-D Itch 
score. Total 5-D Itch scores can range between 5 (no itch) and 25 (most severe itch). A higher 
score indicates worse itch. 

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8.1.13. 
National Institutes of Health Patient-Reported Outcomes Measurement 
Information System (PROMIS)-29 Short Form  
The PROMIS-29 Short Form (Version 2.0) will be used to assess patient-reported state of health. 
The National Institutes of Health established PROMIS (www.nihpromis.org) to create a 
standardized and uniformly scored set of patient-reported-outcomes instruments. The PROMIS 
network developed item (question) banks and Short Forms in more than 20 health domains as 
well as a set of global health items and 29-, 43-, and 57-item profile measures. To create a brief, 
practical-yet-inclusive short profile, a consensus-building process was used to identify 7 of these 
20 domains to produce the PROMIS-29. The seven domains specifically relate to physical, 
mental and social health and cover the most relevant areas of self-reported health for the greatest 
majority of people with chronic illness: pain interference, fatigue, depression, anxiety, sleep 
disturbance, physical function and social role. The PROMIS-29 includes four items each from 
these seven core PROMIS domains as well as one 11-point rating scale for pain intensity. Norm-
based scores have been calculated for each domain, such that a score of 50 represents the mean 
of the general population (standard deviation = 10). High scores represent more of the domain 
being measured. Thus, on symptom-oriented domains of PROMIS-29 (anxiety, depression, 
fatigue, pain interference, and sleep disturbance), higher scores represent worse 
symptomatology. On the function-oriented domains (physical functioning and social role) higher 
scores represent better functioning. 
8.1.14. 
Patient Visual Analog Scale (VAS) scores of Pain 
All subjects will record their overall pain by drawing a vertical mark on a 0-10cm VAS scale. 
The 10-cm VAS is anchored at each end with descriptors of “no pain” (0) and “pain as bad as it 
could be” (10) anchored at each end.   
8.1.15. 
Skindex-29+3 
The Skindex-29 (Chren 1997) is a validated, 29-item skin-specific quality of life questionnaire 
used to calculate three subscales: symptoms, emotions and functioning. The Skindex-29+3 
includes the addition of a fourth subscale, consisting of three questions, to assess photosensitivity 
and alopecia (Klein 2011). Each question and subscale range from 0-100 points, with higher 
scores indicating worse quality of life.  
8.1.16. 
European Quality of Life 5-domain (EQ-5D) questionnaire score  
The EQ-5D is a standardized measure of health status intended to provide a simple and generic 
measure of health and is comprised of 5 dimensions - anxiety/depression, mobility, self-care, 
usual activities, and pain/discomfort. 
8.1.17. 
Patient Improvement Questionnaire for Subjects 
A brief questionnaire (see Appendix 4) will be administered to determine overall improvement 
with treatment from study start (Yes or No), as per the subject’s perception. Subjects who answer 
“Yes” will be asked to rate whether the degree of improvement was slight, moderate, or marked. 
The MID for TIS, HAQ-DI score, and CDASI activity score in DM will be calculated separately 
as the mean score of each of these outcomes in all subjects who answered that they had slight 
improvement at that given timepoint (16 Weeks, 26 Weeks, and 52 Weeks).  

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8.1.18. 
Blood Biomarkers of Inflammation  
Blood to assess biomarkers of inflammation will be collected at Baseline and post-treatment in 
all subjects. The messenger ribonucleic acid (mRNA) levels of key cytokines and chemokines in 
DM will be analyzed. The exact biomarkers to be analyzed will be decided after completion of 
the study, but may include Type 1 IFN, IL-1β, IFNβ, IL-6, IFNγ, and TNFα, and results may be 
reported separately from the main CSR. 
8.1.19. 
Paxgene  
Blood will be collected for transcriptomic analysis, at Baseline and post-treatment in all subjects. 
Results of such analysis may be reported separately from the main CSR. 
8.1.20. 
Blood for Flow Cytometry  
Blood will be collected for flow cytometry at selected sites. It is expected that all subjects at 
these subsites will provide a blood sample for flow cytometry at the visits specified in the SOA.  
8.1.21. 
Autoantibodies  
Blood will be collected to assess autoantibodies commonly seen in DM patients, at Baseline and 
post-treatment in all subjects. Results of such analysis may be reported separately from the main 
CSR. 
8.1.22. 
Skin Biopsies 
Skin biopsies (at Baseline, Visit 4, and at and at the end of treatment [Visit 10 or Early 
Termination]) will be collected in consenting subjects at selected sites. Five 4mm skin biopsies 
will be collected (other than site 1001) 2 each at Visit 1 and Visit 4 respectively for histology and 
transcriptome and 1 at Visit 10 for transcriptome.  The biopsies will preferentially be taken from 
an area of involved skin that is active or worsening, rather than improving, in the opinion of the 
site investigator. No biopsies will be taken from the face, neck, hands or feet. Biopsies should be 
taken from the same location at each biopsy visit, provided that this area is active or worsening at 
that timepoint. If a subject has no active skin involvement in an area that can be biopsied at Visit 
1, then no biopsies should be taken at Visit 1 or any subsequent visit (because there will be no 
Baseline biopsy for comparison). If biopsies are obtained at Visit 1, then subsequent biopsies 
should be obtained within 1-2 cm of the first biopsy sites, without regard to disease activity at 
that site at that time. 
Histology will be evaluated by a blinded pathologist post-treatment and compared to Baseline. 
Flow cytometry may be conducted to analyze cell subsets in the skin and transcriptome analysis 
may be performed to assess RNA levels. Skin biopsy results may be reported separately from the 
main CSR. 
8.1.23. 
Skin Photographs 
Skin photographs will be collected in consenting subjects at selected study sites. An instruction 
manual, detailing standardized procedures for taking skin photographs will be provided. 
Photographs will be taken of pre-specified body areas and any area with the most severe skin 
activity if that area is not included in the pre-specified body areas. Photographs of these areas 

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will be taken at Baseline (Visit 1) and at end of treatment (Visit 10 or ET), regardless of activity. 
The photos should have all identifiers removed to protect the identity and privacy of subjects and 
subjects should be referred to by SID only. Skin photography results may be reported separately 
from the main CSR. 
8.1.24. 
Pharmacokinetic Assessments  
Lenabasum and metabolite plasma concentration will be measured at Visits 1, 2, 4, 6, and 10. At 
Visit 1, blood will be drawn pre-dose and then 3 ± 0.5 hours post-dose at the approximate time of 
the anticipated tmax. At Visits 2, 4, 6, and 10, blood will be drawn pre-dose to assess trough 
concentration levels. To obtain trough concentrations of lenabasum on Visit 2, 4, 6, and 10, the 
blood sample for lenabasum plasma concentration should be obtained between 8 and 16 hours 
after the last dose of study product.  
 
8.2. 
Safety Assessments 
8.2.1. 
Medical History and Use of Contraception  
Medical history will include subject demographics, history of DM and current treatment for DM.  
The medical history also will include concurrent illnesses, other current medications, past 
relevant medical history, smoking history (classified as one of the following: current smoker, 
ever smoker (defined as ≥ 1 cigarette per day for > 1 year), or never smoker), child-bearing 
potential, last menstrual period (LMP) for women, and review of systems.  Date of LMP and 
method of contraception will be assessed at screening and all visits in WOCBP.  
Acceptable contraceptive methods (as stated in Appendix 1), may not be available or approved in 
all countries; thus, the Sponsor does not restrict respective countries from excluding unavailable 
contraceptive methods in the ICF. 
8.2.2. 
Concomitant Medications 
A list of current prescription and over-the-counter medications and supplements will be obtained.  
Concomitant medications and supplements will be recorded on the concomitant medication 
eCRF at screening and all visits.  The medication or supplement, dose, frequency, route, start 
date, stop date and indication will be captured. 
8.2.3. 
Physical Examinations 
A full physical examination will include at a minimum assessments of alertness and orientation, 
general appearance, skin, head, eyes, ears, nose, and throat, lungs, heart, abdomen, 
musculoskeletal examination, and lymph nodes. Breast and genitourinary examinations are not 
required. 
A brief physical examination will include at a minimum assessments of skin, lung, heart, 
abdomen, and any other area as indicated by changes in medical history. 
Medically significant changes that reflect worsening from Visit 1 physical examination will be 
considered AEs and recorded as such. 

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8.2.4. 
Vital Signs, Height and Weight  
Vital signs measurements include blood pressure, pulse rate, respiratory rate, and temperature 
and are assessed at Screening and all study visits. Systolic and diastolic BP will be measured 
with the subject supine for at least 5 minutes. The same arm should be used for the measurement 
throughout the study as much as possible. Pulse and respiration will also be measured with the 
subject supine for at least 5 minutes. Body temperature will be measured on the skin or in the 
mouth. 
Height will be measured in standing position with footwear removed and weight will be 
measured with coats, jackets, and footwear removed. 
8.2.5. 
Electrocardiograms  
Twelve-lead ECGs are to be recorded with the subject in a rested supine position for ≥ 10 
minutes before the test, using ECG machines supplied by the Sponsor. The ECGs will be read 
centrally. The medical significance of any new ECG abnormality will be assessed by the 
investigator. 
8.2.6. 
Clinical Safety Laboratory Assessments  
Blood and urine laboratory safety tests will be performed at each visit with the frequency of 
measures varying between laboratory parameter (sampling visits detailed below). The results of 
all tests will be reviewed by the investigator or designee, who will make judgments on the 
medical significance of any new or worsening abnormal value. New medically significant 
abnormal laboratory results that are related to safety of study product should be repeated as soon 
as possible to confirm the abnormality. The Schedules of Assessments are provided in Table 3 
(Part A) and Table 4 (Part B). 
The results of clinical laboratory tests at the time of last measurement before study product 
administration on Visit 1 will provide Baseline references against which any fluctuations in these 
indices can be compared. 
All blood laboratory tests will be performed in a licensed, central clinical laboratory, to provide 
appropriate longitudinal and cross-site comparisons. The following Screening blood tests will be 
performed by a central laboratory: 
• Complete blood count with differential 
• Human immunodeficiency virus 
− At Screening, a HIV 1/2 antibody test will be performed. If the results are not 
negative, a HIV 1/2 antibody confirmatory test will be performed.  
• Follicle stimulating hormone and leutinizing hormone  
• Hepatitis B and C  
− At Screening, a test for Hepatitis B surface antigen will be performed. If the 
results are positive, a Hepatitis B core antibody confirmatory test will be 
performed. 

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− At Screening, a test for Hepatitis C antibody will be performed. If the results are 
reactive, a Hepatitis C RNA confirmatory test will be performed. 
• Serum β human chorionic gonadotropin, for WOCBP 
• Metabolic panel including glucose, urea nitrogen, creatinine, estimated glomerular 
filtration rate, blood urea nitrogen/creatinine, sodium, potassium, chloride, carbon 
dioxide, calcium, protein total, albumin, bilirubin total, alkaline phosphatase, ALT, 
AST, LDH, CK, Aldolase. 
If retesting is required as part of Screening,  any repeat laboratory screening tests will be done at 
the central laboratory. If returning to the clinic for repeat screening laboratory tests would cause 
major inconvenience for the subject, for example because of long distance travel, repeat 
laboratory tests can be done at a local laboratory only if results are made available to the 
investigator for review before dosing. 
The following urine tests will be performed locally using supplies provided by the Central 
laboratory: 
• Urine β human chorionic gonadotropin, for WOCBP 
• Urine dipstick for blood, protein, and glucose. 
Since this clinical trial is conducted globally, the same lab test kits are used in all countries in 
order to test under the same conditions at each site.  For this reason, several kits that are not yet 
approved by regulatory/governmental agencies (such as MHLW in Japan) will be used (e.g., 
punch for skin biopsy and blood collection tube).  However, these kits have almost the same 
structure and use as kits currently used in Japan and other countries. 
8.2.7. 
Adverse Events and Serious Adverse Events 
8.2.7.1. 
Definition of Adverse Events (AE) 
An AE is any untoward medical occurrence associated with the use of a drug in humans, whether 
or not considered drug related (Code of Federal Regulations Title 21, Volume 5, Section 312). 
Another definition of an AE is any untoward medical occurrence in a patient or clinical trial 
subject administered a medicinal product and which does not necessarily have a causal 
relationship with this treatment (Article 2(m) of Directive 2001/20/EC). 
An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory 
finding, for example), symptom, or disease temporally associated with the use of the study 
product, whether or not considered related to the study product. Intercurrent illnesses or injuries 
will be regarded as AEs. Any event of abuse, misuse or addiction should be reported as an AE. 
Drug abuse is defined as the intentional, non-therapeutic use of a drug product or substance, even 
once, to achieve a desired psychological or physiological effect. Drug misuse is defined as the 
use of a substance for a purpose not consistent with legal or medical guidelines (World Health 
Organization, 2006). Addiction (according to American Psychiatric Association) is a complex 
condition, a brain disease that is manifested by compulsive substance use despite harmful 
consequence (World Health Organization, 2006).  

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When collecting AEs, the recording of diagnoses is preferred (when possible) to recording a list 
of signs and symptoms. However, if a diagnosis is known and there are other signs or symptoms 
that are not generally part of the diagnosis, the diagnosis and each sign or symptom will be 
recorded separately. This definition also includes accidental injuries, reasons for any change in 
medication (drug and/or dose) other than planned titration, reasons for admission to a hospital or 
reasons for surgical procedures.  
Abnormal results of any laboratory test or diagnostic procedure will be considered AEs if the 
event has any of the following characteristics: 
• Results in study withdrawal 
• Is associated with an SAE 
• Is associated with clinical signs or symptoms 
• Leads to additional treatment or to further diagnostic tests (beyond single repeat) 
• Is considered by the investigator to be of clinical significance 
Wherever possible the investigator should report the clinical rather than laboratory term (e.g., 
anaemia versus low haemoglobin value). 
The investigator will assess all abnormal laboratory results for their clinical significance. If any 
abnormal laboratory result is considered clinically significant, the investigator must provide 
details about the action taken with respect to the study product and about the subject’s outcome. 
AEs will be captured from time of signing of IC to the end of the subject’s participation in the 
study.  
Death is not considered an AE, but the cause of death is. An exception is the event of sudden 
death of unknown cause. Similarly, hospitalizations and procedures are not AEs; however, the 
reasons for hospitalization and procedures are. However, if deemed necessary by the 
investigator, a procedure can be captured as an AE, along with the reason for conducting the 
procedure. An overdose or medication error is not an AE unless it is temporally associated with 
an unfavorable or unintended sign or symptom.  
The investigator or designee will report all directly observed AEs and all AEs spontaneously 
reported by the trial subject using concise medical terminology. In addition, each trial subject 
will be questioned about AEs. 
All adverse clinical experiences, whether observed by the investigator or reported by the subject, 
must be recorded, with details about the duration and intensity of each episode, the action taken 
with respect to the study product, and the subject’s outcome. 
8.2.7.2. 
Definition of Serious Adverse Events (SAE)  
Serious AEs are a subset of AEs. A serious adverse event (SAE) is defined as any untoward 
medical occurrence that has any of the following outcomes: 
• Results in death 
• Is life-threatening 

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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. 
• Requires inpatient hospitalization or prolongation of existing hospitalization 
• Results in persistent or significant disability/incapacity 
• Is a congenital anomaly or birth defect in the offspring of a subject 
• Is an important medical event 
Medical judgment should be exercised in deciding whether expedited reporting is appropriate in 
situations where none of the outcomes listed above occurred. Important medical events that may 
not be immediately life-threatening or result in death or hospitalization but may jeopardize the 
subject or may require intervention to prevent one of the other outcomes listed in the definition 
above should also usually be considered serious. Examples of such events include allergic 
bronchospasm requiring intensive treatment in an emergency room or at home, blood dyscrasias 
or convulsions that do not result in inpatient hospitalization, or the development of drug 
dependency or drug abuse. A new diagnosis of cancer during treatment should be considered as 
medically important. 
An AE caused by an overdose or medication error is considered serious if a criterion listed in the 
definition above is fulfilled. Serious AEs also include any other event that the investigator or the 
Medical Monitor judges to be serious or which is defined as serious by regulatory authorities. 
8.2.7.3. 
Adverse Events That Cause Discontinuation 
Adverse events leading to discontinuation of treatment will be recorded and narratives will be 
generated for AEs that caused discontinuation. 
8.2.7.4. 
Disease Worsening 
Any medically significant worsening in DM or a flare, as judged by the investigator, will be 
recorded as an AE. 
8.2.7.5. 
Procedures for Assessing and Recording Adverse Events and Serious Adverse 
Events 
Throughout the duration of the study, the investigator or designees will closely monitor each 
subject. All AEs which occur during the study will be recorded, whether observed by the 
investigator or by the subject and whether thought to be related or unrelated to study product.  
The description of the AEs as recorded on the eCRF will include a description of event, start 
date, stop date, intensity, if it was serious, relationship to study product, what actions were taken 
with respect to the study product, if treatment was required and the subject’s outcome. 
The investigator must evaluate each AE for its relationship to the study product and for its 
seriousness.  All AEs related to study product must be followed until resolution or until they 
become stable. 

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Controlled Substance Reporting 
As required, the site pharmacist or investigator or designee will complete and keep a copy of 
controlled substance forms. 
Unanticipated Problem Reporting to Competent Authorities and Ethics Committees  
Unanticipated problems are events that may occur during a clinical trial which do not fall within 
the definition of suspected unexpected serious adverse reaction (SUSAR) and thus are not 
subject to the reporting requirements for SUSARs, even though they may be relevant in terms of 
subject safety. Examples include:  
• An SAE which could be associated with the trial procedures and which could modify the 
conduct of the trial;  
• A major safety finding from a newly completed animal study (such as carcinogenicity).  
In relevant countries, incidents or events that meet the criteria for unanticipated problems, may 
need to be reported to the EC or competent authority. This information is to be reported to the 
Sponsor using the AE eCRF within 24 hours of learning of the event.  
SAE Reporting 
All SAEs must be reported immediately to the Sponsor (or their designated representative) no 
more than 24 hours after becoming aware of the event. 
Any AE that meets the specified SAE criteria (Section 8.2.7.2) will be recorded on an SAE 
eCRF, by the investigator or qualified designee.  The investigator must complete the SAE eCRF 
immediately, which will prompt an electronic notification to the Sponsor or designated 
representative.  Follow-up information on the SAE will be provided in a timely manner to the 
Medical Monitor and recorded on eCRF form(s).  If eCRF is unavailable, paper forms must be 
completed and submitted to the Sponsor or designated representative expediently to maintain the 
reporting timelines. 
The mandatory reporting of safety events to regulatory authorities will be followed as required 
by applicable regulatory authority, and as per the applicable reporting timelines. Reporting to 
Corbus, regulatory agencies, ECs, and investigators will be in accordance with all applicable 
local laws and regulations.  
Reporting Events to Subjects 
Any change in benefit-risk assessment relating to lenabasum administration will be reported to 
study subjects in compliance with applicable local laws and regulations. 
Reporting of Pregnancy 
Pregnancy itself is not an AE. The effect of lenabasum in pregnancy is unknown. Women 
subjects of childbearing potential will be instructed to inform the investigator if they become 
pregnant during the study or within 4 weeks after taking the final dose of study product. If the 
pregnancy occurs during the treatment period, the investigator should immediately discontinue 
the study product and instruct the subject to return any unused portion of study product to the 
study staff. Pregnancies occurring while the subject is on lenabasum or within 4 weeks after the 
subject’s last dose of lenabasum should be reported by the site to the Sponsor within 24 hours of 

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the site being made aware. The investigator will counsel the subject about the risks of the 
pregnancy and the possible effects on the fetus. 
To report pregnancies in subjects, the investigator or qualified designee must submit a Pregnancy 
Reporting Form to the Sponsor (or their designated representative) within 24 hours after learning 
of the pregnancy. The pregnancy must be reported to the EC within 24 hours of the investigator’s 
knowledge of the pregnancy. The subject should be referred to an obstetrician/gynecologist 
experienced in reproductive toxicity for further evaluation and counselling. The investigator or 
qualified designee will follow the subject until completion of the pregnancy or 30 days after the 
birth, as applicable, and report follow-up findings to the EC.  
Please note that pregnancy in the female partner of a male study subject is also a reportable 
event, and the same timelines and reporting procedures should be followed. 
If the outcome of the pregnancy meets the criteria for immediate classification as an SAE (i.e., 
spontaneous abortion [any congenital anomaly detected in an aborted fetus is to be documented], 
stillbirth, neonatal death, or congenital anomaly), the investigator should follow the procedures 
for expedited reporting of SAEs to the EC within 24 hours of knowledge of the event. All 
neonatal deaths that occur within 30 days of birth should be reported as SAEs without regard to 
causality. 

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9. 
STATISTICAL CONSIDERATIONS  
9.1. 
Statistical Hypotheses 
9.1.1. 
Primary Efficacy Endpoint 
Week 28 TIS: 
H0: 
The difference in the TIS between the active group and placebo (lenabasum group  
placebo) at Week 28 = 0. 
H1: 
The difference in the TIS between the active group and placebo (lenabasum group – 
placebo) at Week 28 ≠ 0, with superiority of active to placebo claimed if the difference 
between the active group and the placebo group > 0 (i.e., indicates greater improvement 
in the active group). 
9.2. 
Sample Size Determination 
This study is expected to Screen 200 subjects with 150 subjects anticipated to be dosed at a ratio 
of 2:1:2; 60 subjects in the lenabasum 20 mg BID cohort, 30 subjects in the 5 mg BID cohort, 
and 60 subjects in the placebo cohort. Given 150 dosed subjects, it is expected that 120 subjects 
will complete at least Week 28 assuming a ~20% drop out rate. This is based on a TIS treatment 
group difference of 15.0, standard deviation (SD) 20.00, Alpha 0.05 two-sided, Power 95%.  
The final number of subjects to be dosed will be decided based on a blinded interim analysis to 
assess variability in the TIS score as described in the SAP and Section 9.4.7.  
9.3. 
Populations for Analyses 
There are 4 analysis populations defined in this study: 
The modified intent to treat (mITT) population will consist of all randomized subjects who 
have received at least one dose of study product. Analysis of the modified ITT population will be 
used as the primary efficacy analyses and will analyze subjects under the treatment to which they 
were randomized, regardless of compliance with assigned treatment. 
The per protocol (PP) population will consist of subjects who complete the study without 
major protocol violations deemed likely to affect the efficacy outcomes of interest (these 
deviations will be classified during a blinded deviation review meeting before unblinding the 
study). Analysis on the PP population will be used as secondary efficacy analyses, analyzing 
subjects under the treatment actually received. 
The safety population (SAF) will consist of all subjects who received any study product. 
Analysis performed on the safety population will be according to the treatment actually received. 
The pharmacokinetic (PK) population will consist of all subjects from the SAF whose 
pharmacokinetic data are adequate for the calculation of primary PK parameters. Inclusion in the 
PK population of subjects with missing data or protocol violations or inadequate dosing will be 
considered on a case-by-case basis. The PK population will be the analysis set used for all 
pharmacokinetic analyses. 

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9.4. 
Statistical Analyses 
9.4.1. 
General Approach 
All data will be provided in data listings sorted by treatment group, subject number, and visit. 
Summary data will be presented in tabular format by treatment group. Categorical data will be 
summarized by the number and percentage of subjects in each category. Continuous data will be 
summarized by descriptive statistics including the sample size (n), mean, standard deviation, 
median, minimum and maximum. All percentages will be rounded to one decimal place. 
Differences between treatment groups will be calculated as lenabasum  placebo and change 
from Baseline will be calculated as visit  Baseline. The Baseline measure will be defined as the 
last non-missing measure before initiation of study product.   
Data will be presented by randomized treatment group for efficacy data and by actual treatment 
group for safety data. 
P-values and 2-sided 95% confidence intervals will be presented for all efficacy endpoints. 
9.4.1.1. 
Handling of Missing Data 
The analysis of the primary endpoint will be performed on the mITT population, using a mixed-
effect model for repeated measures (MMRM), on observed data, using last observation carried 
forward (LOCF) for ≤ 2 missing core set items. If more than 2 core items are missing, the TIS 
score will not be calculated for that visit.  Sensitivity analyses for the primary endpoint will 
include imputing missing data using last observation carried forward, the completer population, 
and the per-protocol population.  
9.4.1.2. 
Adjustments for Multiplicity 
The overall type I error rate will be controlled for primary and secondary outcomes with a 
hierarchical ordering of assessments. The order of the tests for treatment effect will be as 
follows: 
• Primary efficacy outcome: Mean TIS, lenabasum 20 mg BID versus placebo, at Week 28. 
• Secondary efficacy outcomes (Change from Baseline at Week 28): 
The following endpoints will be compared in lenabasum 20 mg BID compared to placebo 
cohorts and lenabasum 5 mg BID compared to placebo cohorts at Week 28.  All outcomes 
involving continuous variables will be assessed as absolute values and, if relevant, change from 
Baseline.  All categorical variables will be assessed as number and proportion of subjects in each 
category. The list will be done in order below for comparisons between lenabasum 20 mg BID 
and placebo cohorts: 
• Subjects who achieve DOI  
• Subjects who improve by at least one category on the IGA scale of skin activity 
• Subjects who achieve TIS ≥ 40 (at least moderate improvement) 
• TIS in subjects receiving any immunosuppressant medication for > 1 year at Baseline 
• TIS at Week 52 
• CDASI activity score 

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The list will continue in order below for comparisons between lenabasum 5 mg BID and 
placebo cohorts: 
• TIS 
• Subjects who achieve DOI Subjects who improve by at least one category on the IGA 
scale of skin activity 
• Subjects who achieve TIS ≥ 40 (at least moderate improvement) 
• TIS in subjects receiving any immunosuppressant medication for > 1 year at Baseline 
• TIS at Week 52 
• CDASI activity score 
Note that, in Part A, statistical significance for each endpoint must first be achieved in order to 
continue in the assessment of the next endpoint, following the testing sequence above. 
9.4.2. 
Analysis of the Primary Efficacy Endpoint(s) 
The primary efficacy variable is the TIS. The primary analysis is to compare the TIS at Week 28 
between the lenabasum 20 mg BID treated group and placebo using a mixed model for repeated 
measures (MMRM). The model will have TIS score as a dependent variable, treatment, visit, 
treatment*visit interaction, baseline MMT-8 score, baseline prednisone use, and region as fixed 
factors, and subject as a repeated random effect. The model may incorporate other baseline 
factors as covariates, which will be further defined in the statistical analysis plan. Two-sided p-
values and 95% confidence intervals associated with the least-square (LS) mean difference 
between the lenabasum group and placebo will be presented for each visit.  If the distribution of 
the TIS score does not meet the assumptions of normality, a nonparametric analysis may be 
performed (e.g., MMRM analysis on the ranked data). 
Two-sided p-values and 95% confidence intervals associated with the least-square (LS) mean 
difference between the lenabasum group and placebo will be presented for each visit. 
Because TIS is a composite score, absolute values and change from Baseline in each core set 
measure will be presented to support the primary efficacy endpoint. 
9.4.3. 
Analysis of the Secondary Efficacy Endpoint(s) 
Continuous secondary and tertiary outcome variables will be analyzed similarly to the primary 
MMRM model, using change from Baseline as the dependent variable, with the Baseline of each 
endpoint also included in the model.  Other outcomes based on the proportion of subjects 
achieving defined criteria will be analyzed using a Fisher’s exact or Cochran-Mantel-Haenzel 
test. 
Secondary efficacy endpoints in this study include: 
1. Subjects who achieve DOI 
2. Subjects who improve by at least one category on the IGA scale of skin activity  
3. Subjects who achieve TIS ≥ 40 (at least moderate improvement) 
4. TIS in subjects receiving any immunosuppressant medication for > 1 year at Baseline 
5. TIS at Visit 10 (Week 52) 
6. CDASI activity score 

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7. TIS (lenabasum 5 mg compared to placebo cohort only) 
9.4.4. 
Analyses of the Tertiary Efficacy Endpoints 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
  
 
 
  
 
 
 
 
 
 
 
 
 
  
 
 
 
 
  
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
p
 
 
  
 
 
 
 
 
 
  
  
   
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
  
 
 
 
p
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
  
 
 
 
 
 
 
 
9.4.7. 
Safety Analyses 
No formal statistical testing will be performed to compare the safety in lenabasum versus 
placebo cohorts. 
The number and percentage of subjects with AEs will be summarized for each treatment by 
system organ class and preferred term. Similar summaries will be presented for AEs related to 
study product, AEs leading to permanent discontinuation of study product, SAEs, and AEs 
resulting in death. Any AE with a relationship category of possible, probable, or definite is 
considered related to study product. The AEs will be coded using the Medical Dictionary for 

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Regulatory Activities (MedDRA) using the latest version available. All reported AEs will be 
provided in separate data listings.  
Descriptive statistics will be used to summarize clinical laboratory parameters, vital signs and 
their corresponding mean change from Baseline for each treatment by scheduled timepoint. For 
all lab parameters shift tables will also be generated. 
The number and percentages of subjects with normal, abnormal and clinically significant, and 
abnormal and not clinically significant ECG findings during treatment will be summarized for 
each treatment by scheduled timepoint. QTcF change from Baseline for each treatment would be 
calculated. Tables with number of subjects with QTcF > 500 msec, 30 msec change from 
Baseline, 60 msec change from Baseline will be presented. 
9.4.8. 
Baseline Descriptive Statistics 
Subject demographics of gender, race, ethnicity, and age will be presented using discrete 
summary statistics. Age at the time of IC will be presented using continuous summary statistics.  
Medical history will be summarized by treatment group using discrete summaries by coded 
terms (MedDRA - system organ class and preferred term). Other Baseline characteristics will be 
summarized by treatment group using discrete or continuous summary statistics as appropriate. 
9.4.9. 
Planned Interim Analyses  
The number of subjects to be dosed may be adjusted further during the study after a blinded 
interim analysis of the emerging data. The timing and methods for the interim analysis will be 
outlined in the SAP.  The intent is to perform a blinded interim examination of the variance of 
the TIS, to potentially increase the sample size to maintain power (with no statistical adjustment 
to the alpha level required). The projected maximum number of subjects to be randomized is 230 
subjects (for 183 completers), which corresponds to standard deviation of 30, and 85% power. 
9.4.10. 
Tabulation of Individual Subject Data 
Individual subject data (demographic, safety, and efficacy) will be provided in listings for 
Screening, active treatment period, and Follow-up. 
9.4.11. 
 Part B 
The same efficacy and safety parameters described as primary and secondary objective for Part 
A will be evaluated in Part B as described in the SAP.  
 
 

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10. 
SUPPORTING DOCUMENTATION AND OPERATIONAL 
CONSIDERATIONS 
10.1. 
Regulatory, Ethical, and Study Oversight Considerations 
10.1.1. 
Ethical Conduct of the Study 
This study will be conducted in accordance with United States (US) and international ethical 
principles that have their origins in the Declaration of Helsinki Protection of Human Volunteers 
[21 Code of Federal Regulation (CFR) 50], Institutional Review Boards (21 CFR 84), and 
Obligations of Clinical Investigators (21 CFR 312), in compliance with the approved protocol, 
Good Clinical Practice (GCP), Food and Drug Administration (FDA) Title 21 part 312, 
European Union clinical-trial legislation (Directive 2001/20/EC), Japanese Good Clinical 
Practice (J-GCP), the Ministerial Ordinance on Good Clinical Practice for Drugs in Japan (where 
applicable), ICH guidelines, applicable government regulations, and institutional research 
policies and procedures. The investigator will ensure, through reporting to Corbus, that the 
relevant regulatory agencies are advised, according to their timelines for reporting, of all changes 
post-study initiation that may in any way affect the safety of subjects. 
10.1.2. 
Ethics Committee/ Institutional Review Board 
This protocol will be submitted to the reviewing central or local Institutional Review Board 
(IRB) or Independent Ethics Committee (IEC), hereafter referred to as the Ethics Committee 
(EC), for review and approval before the study is initiated at any site. The EC must be 
constituted according to the local laws/customs of each participating country. Any protocol 
amendments will be submitted to the reviewing central or local EC for review and approval. The 
EC will review the informed consent form (ICF), its updates if any, and any written materials 
given to the subjects. Any other documents that the EC may need to fulfill its responsibilities, 
including subject recruitment procedures and any compensation available to subjects, will be 
submitted to the EC by the local monitor/investigator. The EC’s written unconditional approval 
of the study protocol and the ICF will be in the possession of the investigator and Corbus before 
the study is initiated. The EC’s unconditional approval statement will be transmitted by the 
investigator or designee to Corbus before shipment of study product supplies to the site. This 
approval must refer to the study by exact protocol title and number and should identify the 
documents by date and version reviewed, the date of review, and any updates after initial 
approval. 
Corbus will write any amendment to the protocol that is needed. Protocol and/or IC 
modifications or changes may not be initiated without prior written EC approval except when 
necessary to eliminate immediate hazards to the subjects or when the change(s) involves only 
logistical or administrative aspects of the study. Such modifications will be submitted to the EC, 
and written verification that the modification was submitted should be obtained.  
The investigator or designee is required to notify the EC of the following: 
• Revisions of documents originally submitted for review. 
• SAEs including SUSARs occurring during the study. Corbus will also be notified. 

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• New information that may adversely affect the safety of the subjects or the conduct of the 
study. Corbus will also be notified. 
• Pregnancies occurring in female subjects or female partners of male subjects. Corbus will 
also be notified. 
• Annual update and/or request for re-approval. 
• Suspension or premature termination of the study. Review and approval by the EC is 
required for resumption of the study at a site, in the event the study is interrupted. 
• Study completion. 
The investigator must keep copies of all AE information, including correspondence with Corbus 
and the approving EC, on file. The investigator will retain all EC records related to this 
investigation for at least 3 years, or as long as required by local regulations, after completion of 
the research. 
Investigator will permit study-related monitoring, audits and inspections of all study related 
documents by the approving EC. Should direct access to medical records require a waiver or 
authorization separate from the subject’s statement of informed consent, the investigator or 
designee is obligated to obtain such permission in writing from the appropriate individuals. 
10.1.3. 
Informed Consent Process 
10.1.3.1. Consent and Other Informational Documents Provided to Subjects 
ICFs describing in detail the study intervention, study procedures, and risks are given to the 
subject and written documentation of IC is required before starting intervention/administering 
study intervention. 
10.1.3.2. Consent Procedures and Documentation 
The investigator will prepare the ICF and Health Insurance Portability and Accountability Act 
authorization (US only) and provide the documents to Corbus for approval before submission to 
the EC. The consent form generated by the investigator must be acceptable to Corbus and 
approved by the EC. The written consent document will embody ICH elements of IC and comply 
with local regulations. The investigator will send EC-approved copies of the ICF to Corbus for 
the study file. 
The principles of IC in the current edition of the Declaration of Helsinki must be implemented 
before any protocol-specified procedures or interventions are carried out and will also comply 
with local regulations. IC will be obtained by the investigator or designee in accordance with 21 
CFR 50.25 or Directive 2001/20EC, depending upon site location in the US or EU, respectively. 
Information will be given in both oral and written form, and subjects must be given ample 
opportunity to inquire about details of the study. 
ICFs must be written at a level that can be understood by the prospective subject. The 
explanation of the investigation will be in language that is understandable to the individual. If 
non-English speakers are enrolled, a translated consent document will be available, and an 
appropriate person will conduct the consent process. Subjects who so choose will be given the 

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opportunity to take the consent home for review with other family members or their medical 
doctor.  
If a subject is ≥ 18 and < 20 years of age and additional parental / guardian consent is required by 
local / national regulators to participate in this clinical trial, then the unique requirements for that 
country will be followed for those subjects.  
Before IC is obtained from potential subjects, the investigator or designee will explain the 
purpose, study design and potential benefits/risks of participation in the study including that 
some risks may be unforeseen. The explanation will include a statement that treatment in the 
study may involve risks to the subject or the fetus, if the subject should become pregnant. 
Subjects must be informed about alternative treatments. Subjects must receive an explanation as 
to whether any compensation and any medical treatments are available if injury occurs and, if so, 
what they consist of, or where further information may be obtained. They must be informed 
whom to contact for answers to any questions relating to the research project. The subjects must 
be informed that participation is voluntary and that they are free to withdraw from the study for 
any reason at any time, without penalty or loss of benefits to which they are otherwise entitled. 
The ICF will explain the option of allowing leftover blood samples to be used in future research 
related to lenabasum, inflammation or DM. This option requires individual consent. If the subject 
declines to participate in this option, that choice will have no effect on his/her eligibility and will 
not interfere with the benefits to which he/she is otherwise entitled. 
The extent of the confidentiality of subject records will be defined. Subjects will be informed 
that the study will comply with applicable data protection legislation. Health Insurance 
Portability and Accountability Act authorization (US only) will be obtained before conducting 
any protocol-related procedures, including screening evaluations. Subjects must be informed 
that, by signing the written ICF, they are granting direct access to their original medical records 
for verification of clinical trial procedures and/or data to the site monitor(s), medical monitor, 
auditor(s), EC representatives, and other regulatory authorities. Subjects’ medical information 
obtained in this study is confidential and may be disclosed to third parties only as permitted by 
the ICF or separate authorization for use and disclosure of personal information signed by the 
subject, unless permitted or required by law. 
10.1.4. 
Confidentiality and Privacy  
Privacy and confidentiality of a subject will be respected throughout the study. Consented 
subjects who meet eligibility for the study will receive a unique SID. These SIDs rather than 
names will be used during collection, storage and reporting of subject information. This number 
will be linked only through a secure SID log that connects each subject to his/her data. 
Information about subjects will be kept confidential and managed per the requirements of the 
relevant regulatory authority. These regulations require a signed subject authorization informing 
the subject of the following: 
• What protected health information will be collected from subjects in this study. 
• Who will have access to that information and why. 
• Who will use or disclose that information. 

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• The rights of a research subject to revoke their authorization for use of their protected 
health information. 
If a subject revokes authorization to collect or use protected health information, Corbus by 
regulation will retain the ability to use all information collected before the revocation of subject 
authorization. For subjects that have revoked authorization to collect or use protected health 
information, attempts will be made to obtain permission to collect at least vital status that the 
subject is alive at the end of their scheduled study period. 
Should direct access to medical records require a waiver or authorization separate from the 
subject’s statement of informed consent, the investigator is obligated to obtain such permission 
in writing from the appropriate individuals. 
10.1.5. 
Future Use of Stored Specimens and Data  
Potential future use of stored specimens and other identifiable data include: 
• Storage for and use of left-over blood and skin samples in future research related to 
lenabasum or DM (optional) 
Left-over blood samples will be stored and may be used in future testing related to lenabasum or 
DM, as indicated by the results of this study and done by Corbus and its collaborators, including 
site investigators. 
The subject has the option to refuse any or all of these options without jeopardy to their 
participation in the clinical trial or clinical care. The blood and skin samples will be maintained 
for up to five years from the completion of LPLV in Part A. To protect confidentiality for any 
future studies with the stored specimens, specimens will be barcoded and de-identified. 
Pharmacogenomic (DNA) analysis will not be performed on any samples. 
 
 

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10.1.7.2. Data Monitoring Committee (DMC) 
Oversight of subject safety in this trial will be provided by an independent unblinded DMC, 
which will advise Corbus and the investigators. The voting members of the DMC will include at 
least 3 external experts in DM who will be supported by an un-blinded biostatistician, who will 
be a non-voting member. A non-voting member may be added to provide clarifications and 
historical perspective, at least during Open Sessions of the DMC meeting. Additional experts in 
areas related to DM, safety, or regulatory requirements or practices can be added as needed. 
The independent DMC will review the accumulated safety and operational data about every 6 
months through the last subject/last visit or more frequently, if necessary. The DMC will review 
interim/cumulative data for evidence of study-related AEs and factors external to the study such 
as scientific or therapeutic developments that may impact subject safety. The DMC will also 
review progress of the study and efficacy outcomes. The DMC may make recommendations to 
Corbus about any of the items it reviews. In addition, if any of the following events occur during 
the enrollment, then the DMC will review all cumulative safety information and the event(s) of 
interest: 
• Death in any subject related to lenabasum. 
• Two life-threatening clinical events that are probably or definitely-related to 
lenabasum. 
• Determination of unexpected, significant, or unacceptable risk to subjects in the 
opinion of the Corbus Chief Medical Officer.                                                                                          
The DMC should conclude each review with written recommendations to Corbus as to whether 
the study should continue without change, be modified, or terminated. Recommendations 
regarding modification of the design and conduct of the study could include whether study 
entry/randomization and dosing should be discontinued, whether the protocol should be 
modified, whether the study should be discontinued permanently, and reasons for these 
recommendations. 
10.1.7.3. Medical Care and Day-to-Day Safety of Subjects at the Site 
The investigator is responsible for all clinical trial-related medical decisions at his/her site and 
will oversee the day-to-day safety of subjects at his/her site. The investigator will review all AEs, 
laboratory results, safety data regarding the subjects’ clinical course and AE profiles for subjects 
at that site, in conjunction with site staff. The investigator should regularly assess the number 
and type of AEs in this study at that site. 
Any qualified healthcare provider may provide medical care when necessary. The investigator 
will advise subjects if medical care beyond the scope of the study is needed. Additionally, it is 
recommended that a subject’s primary care physician be notified of a subject’s participation in 
this research study. 
10.1.8. 
Quality Assurance and Quality Control 
Quality control procedures will be implemented including the eCRF specifications, the data 
validation plan, data management plan, and other plans, procedures and Standard Operating 

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Procedures. Any missing data or data anomalies will be communicated to the site(s) for 
clarification/resolution 
Following written Standard Operating Procedures, the monitors and other study team personnel 
will verify that the clinical trial is conducted and data are generated and biological specimens are 
collected, documented (recorded), and reported in compliance with the protocol, International 
Conference on Harmonization Good Clinical Practice (ICH GCP), and applicable regulatory 
requirements [e.g., Good Laboratory Practices (GLP), Good Manufacturing Practices (GMP)].  
The investigational site will provide access to all trial related sites, source data/documents, and 
reports for monitoring and auditing by the Sponsor and inspection by local and regulatory 
authorities. 
10.1.8.1. Clinical Monitoring 
The investigator will monitor data quality from his/her site on a regular basis throughout the 
study and monitor for compliance with the protocol, applicable government regulations, Good 
Clinical Practice, the site’s standard operating procedures, and the local EC, when applicable. 
The investigator will allocate adequate time for these monitoring activities. 
The investigator and institutions involved in the study will permit study-related monitoring by 
Corbus, designated CROs, government agencies and other regulatory groups, if requested, and 
provide direct access to all study records at the site and to the facilities. Adequate time and space 
for monitoring visits should be made by the investigator and site staff. 
Data quality will be monitored by Corbus or a designated CRO on a regular basis throughout the 
study period. The electronic record will be monitored/audited for the purposes of the study data 
management by site monitors and other study team personnel. A site monitor representing 
Corbus will visit study facilities at periodic intervals, in addition to maintaining necessary 
contact through telephone, e-mail, and letter. The monitor will assess: subject enrollment and 
informed consent procedures; investigational product storage, dispensing, administration and 
accountability; compliance with protocol procedures; completeness and accuracy of data entered 
onto the EDC; and the occurrence of AEs. All aspects of the study will be carefully monitored 
for compliance with the protocol, the study monitoring plan, applicable government regulations, 
GCP, and the site’s standard operating procedures. 
The investigator or a member of the study team must be available to the monitor during 
monitoring visits to review data, resolve queries and review the subjects’ records (e.g., medical 
records, doctor office and hospital charts and study-related information) for source data 
verification. 
The monitor will discuss the conduct and progress of the study with the investigator and site 
staff. The investigator must cooperate with the monitor to ensure that any problems noted during 
monitoring are resolved. 
10.1.8.2. Audit and Inspection of Sites 
Participation by the investigator in this study implies acceptance of potential inspection by 
government regulatory authorities and applicable institutional compliance and quality assurance 
offices. During the conduct of the study, Corbus may conduct audits of any data and facility 
participating in the study. The investigators and institutions involved in the study will permit 

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such study-related audits and provide direct access to all paper study records not contained 
within the electronic medical record or eCRFs and to the facilities. The investigator must 
maintain a comprehensive and centralized filing system of all study-related documentation that is 
not part of the electronic medical record or eCRFs and that is suitable for inspection by Corbus 
or its designated site monitors, Quality Assurance monitors, EC representatives, and 
representatives of government regulatory bodies. The investigators agree to participate in audits 
conducted at a convenient time in a reasonable manner. 
Government regulatory authorities or representatives from ECs may also perform inspections 
either during or after the study. In the event of an inspection by any regulatory authority, the 
investigators will promptly notify Corbus and will allow Corbus representatives to be present 
during the audit, if permitted by the regulatory authority and institutional policy. The 
investigators agree to cooperate fully with inspections conducted by regulatory authorities and to 
allow representatives of the regulatory authority access to all study records. The investigator will 
forward to Corbus a copy of any inspection records received. 
10.1.9. 
 Data Handling and Record Keeping 
10.1.9.1. Data Handling, De-Identification and Source Records 
The investigators and designees will maintain appropriate records for this study, in compliance 
with ICH E6, Section 4.9 and regulatory and institutional requirements for the protection of 
confidentiality of subjects. All study records will be maintained in accordance with Corbus’ 
policies and applicable regulatory requirements. There may be circumstances for which Corbus 
is required to maintain study records and, therefore, Corbus should be contacted before removing 
study records for any reason. 
Source data/records contain all the information, which is necessary for the reconstruction and 
evaluation of the study. The primary source document for this study will be the subject’s medical 
record on site stored in paper form or in an electronic medical record. If separate research 
records are maintained by the investigator, both the medical records and the research records will 
be considered the source documents for the purposes of auditing the study. Data recorded on 
source documents will be transcribed by site staff onto eCRFs provided by Corbus or its 
designee. 
In addition, in this study at the time of the office visit, study-specific original data elements such 
as responses to questionnaires may be entered directly into an electronic system without first 
being transcribed on other media such as paper. There will be no separate source document for 
data entered directly into the electronic system.  
Source data/records are: 1) original records; 2) certified copies of original records; 3) 
observations; 4) laboratory reports; and 5) eCRFs and/or data sheets. Source data/records are to 
be kept by the investigator until the end of the regulatory retention period. All clinical findings, 
observations, laboratory results, subject correspondence, SAE reports, and other information 
related to subject participation in the study must be maintained in subject binders that contain 
source documents and other data collection instruments designed specifically for this 
investigation. Completed eCRF pages will be reviewed by Corbus or Corbus authorized 
personnel. 

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The investigator will permit study-related monitoring, audit(s), EC review(s) and regulatory 
inspection(s), with direct access to all the required source documents. Site staff will permit 
authorized representatives of Corbus, EC and government regulatory agencies to examine (and 
when required by applicable law, to copy) study records for the purposes of quality assurance 
reviews, audits, and evaluation of the study safety, progress and data validity. 
10.1.9.2. Original Records 
Clinical trial data will be recorded on source documentation and entered by the investigator or a 
qualified designee into a validated 21 CFR Part 11 compliant internet-based EDC system. 
Changes to the clinical trial data can only be performed by the investigator or qualified designee 
through the change management methodology that is subject to a full audit trail.  
The investigators and qualified designees should be trained on the EDC system before 
enrollment of the first subject at their site. A list of the status of each user, including an audit trail 
of status changes, will be maintained. 
At the end of the study, the completed eCRF must be reviewed and signed electronically by the 
investigator or a co-investigator authorized to sign. A certification must be obtained from all 
authorized persons to sign electronically indicating that their electronic signature is equivalent to 
their hand-written signature. 
10.1.9.3. Confidentiality of Subject Data 
To maintain subject confidentiality, subjects will not be identified by name, subjects will be 
assigned a site number and subject number for any documentation submitted to Corbus. 
Additional subject confidentiality issues, if applicable, are covered in accordance with each 
participating country, and institution’s laws, regulations and policies. 
10.1.9.4. Data Collection and Management Responsibilities  
Data collection and accurate documentation are the responsibility of the investigator and site 
staff under the supervision of the investigator. All source documents and laboratory reports must 
be reviewed by the study team and data entry staff, who will ensure that they are accurate and 
complete. A site monitor for Corbus will ensure the data are collected and maintained correctly 
and in compliance with Section 10.1.8.1. 
Electronic data capture on eCRFs will be used, using internet access with password protection 
and data quality checks. It is expected that the eCRFs should be submitted coincident with the 
subject visit or within 5 business days. 
A Data Monitoring Plan will be created to specifically identify how data management will be 
performed for the study. The following summarizes this plan: 
• The clinical database will be held and managed by an EDC vendor. The EDC will be 
used for online edit checks, batch edit checks and query management 
• A Data Validation Plan will be created which will include the specifications for:  
o Online checks performed by the EDC system during data entry 
o Batch edit checks 

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o Manual checks performed by the site monitor, Medical Monitor data 
management, and/or other study team personnel 
• Other data cleaning activities such as data reconciliation and coding listing reviews 
will be performed. 
Queries are handled within the EDC application where the monitors and data managers can 
generate a query. Under direction of the investigator, the site team addresses the query. If the 
query is due to a data entry error, the site staff can immediately make the corrections in the 
applicable eCRF pages. If the query needs clarification, the site staff contacts the investigator for 
resolution. The site coordinator then enters the correct value or submits an answer to the query 
without modifying the data. The monitor or data managers then review the corrected eCRF pages 
and/or answer. If the data are changed correctly or the answer is acceptable, the monitor or data 
manager closes the query. If the answer is not acceptable, the monitor or data manager submits 
an additional query for clarification. All changes to the database require a “Reason for Change” 
and are subject to an audit trail. The audit trails identify the changed data, reason(s) for change, 
who changed the data, and the time and date of the change. 
Centralized monitoring will be performed daily or at an agreed-upon frequency, as defined in the 
Data Monitoring Plan. The sites will receive feedback about data quality and data management 
issues at their own sites.  Corrective actions will be implemented as necessary.  
Routine EDC management reports will be available to view the data for consistency. Additional 
management reports will be obtained and reviewed, as indicated during the study. 
10.1.9.4.1. Trial Master File 
The Trial Master File for Corbus will be maintained within an electronic document storage 
system using 21 CFR Part 11 compliant software. 
10.1.9.5. Study Records Retention 
The investigator must ensure that the following records and documents pertaining to the conduct 
of the study and the distribution of study product are retained for as long as needed to comply 
with national and international regulations (generally 2 years after discontinuing clinical 
development or after the last marketing approval): copies of the study specific documents and 
other sources of information such as original medical documents, data and records (such as 
hospital records, clinical and office charts, laboratory notes, memoranda, documents regarding 
subject treatment and study product accountability, and original signed ICFs). All EC records 
related to this study will be retained by the site for as long as required by the local EC. 
In the event the investigator retires, relocates or for any other reason withdraws from the 
responsibility for maintaining records for the time required, custody of the records may be 
transferred to any other qualified person who will accept responsibility for the records. Notice of 
such a transfer must be given in writing to Corbus. The investigator must contact Corbus before 
disposal of any records related to this study.  
10.1.10. 
 Protocol Deviations  
The investigator should not implement any deviation from or changes of the protocol without 
agreement by Corbus and prior review and documented approval from the reviewing EC, except 

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where necessary to eliminate an immediate hazard to trial subjects or when the change involves 
only logistical or administrative aspects of the trial (e.g., change in monitor[s], change of 
telephone number[s]). 
The investigators and site staff are responsible to follow the written protocol as provided by 
Corbus and approved by their EC.  
A protocol deviation is an excursion from the protocol that is not implemented or intended as a 
systematic change and that has not received prior approval by the reviewing EC. There are 
several types of protocol deviations with different requirements for reporting each type of 
deviation. 
An emergency protocol deviation occurs in an emergency when an excursion from the protocol 
is required to protect the life or physical well-being of a subject. The medical monitor and the 
reviewing EC must be notified as soon as possible, but not later than 5 days after the emergency 
occurred. The medical monitor will be notified through the EDC system. Relevant regulatory 
agencies will be notified according to their timelines for reporting.  
A major protocol deviation occurs in a non-emergency when the subject, investigator or Corbus 
fails to adhere to significant protocol requirements affecting the inclusion, exclusion, subject 
safety or primary endpoint criteria. Major protocol violations for this study include but are not 
limited to any of the following: 
• Failure to comply with GCP guidelines 
• Failure to meet eligibility criteria at randomization 
• Use of a prohibited concomitant medication 
• Failure to obtain all TIS core set measurements at Visit 1 or Visit 10 
•  Failure to report AE/SAE in a timely manner 
Major protocol deviations must be reported to Corbus electronically in the manner specified 
within 5 days of the first time the investigator or site staff becomes aware of the deviation and 
must be reported to the EC within that EC’s guidelines. Corbus will determine if an emergency 
or major protocol violation should result in early discontinuation of study treatment for a subject.  
A copy of the Major Protocol Deviation Form will be filed in the site’s regulatory binder and in 
Corbus’ files. The site will report the violation to their EC in accordance with their EC reporting 
requirements. 
A minor or administrative protocol deviation is an excursion from the protocol that does not 
affect the scientific soundness of the research plan or the rights, safety, or welfare of human 
subjects. Examples of minor or administrative deviations could include: follow-up visits that 
occurred outside the protocol required time frame because of the subject’s schedule or blood 
samples obtained at times close to but not precisely at the time points specified in the protocol. If 
a protocol deviation occurs which meets this definition, the deviation should be reported to the 
reviewing EC (if reporting is required) at the time stipulated such as when the continuing review 
application is submitted. These minor or administrative deviations will be reported by the 
investigator or designee in the specified manner within 28 days after their occurrence. 

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10.1.11. 
 Schedule and Contents of Report 
Reports will be generated for Corbus to monitor enrollment and study conduct.  Blinded safety 
monitoring reports will be generated for the medical monitors and the Medical Officer of Corbus 
and un-blinded safety reports will be generated for the DMC. 
The final study report will be generated separately and only after the database is locked.  The 
final study report that will be generated will be stipulated in the final SAP and any amendments 
to that SAP. 
10.1.12. 
 Publication and Data Sharing Policy 
Any information relating to the study product or the study, including any data and results from 
the study, will be the exclusive property of Corbus.  The investigators and any other persons 
involved in the study will protect the confidentiality of this proprietary information belonging to 
Corbus. 
Corbus will conduct this clinical study in an ethical and rigorously scientific manner, in 
collaboration with clinical experts in DM. Corbus will facilitate publication of the clinical data 
from this study in a timely, objective, accurate, and balanced manner. The goal is to have 
submission of the primary manuscript for peer-review within 12 months of generation of the full 
set of Tables and Listings. Corbus will follow publication guidelines that are consistent with 
requirements of the International Committee of Medical Journal Editors, the Consolidated 
Standards of Reporting Trials group, and the individual journal. Corbus will work with 
investigators on this clinical study to produce any manuscripts for peer-reviewed publication. 
Publication by the site of any data from this study must be carried out in accordance with the 
clinical trial agreement. 
This clinical study will be listed on websites (e.g., www.clinicaltrials.gov) as required by 
relevant regulatory authorities. Synopses of the clinical results will be provided on those same 
sites per timeframes established by those regulatory authorities. 
The electronic study database for this clinical study will reside at an external vendor selected by 
Corbus. Corbus retains unlimited access to and use of the study database. Plans for data analyses 
by biostatisticians are part of this study protocol. All authors of a planned publication will be 
provided with the statistical analysis plan and the statistical report, redacted to be relevant to the 
planned publication. For the primary report of this clinical trial, this will include a full 
accounting of subject disposition. Corbus will allow investigators to review the complete study 
database, on request. 
Corbus will provide a copy of the clinical trial protocol and statistical analysis plan to a medical 
journal when a submitted manuscript is being considered for publication on request by the 
journal. Corbus will allow the journal to post on its website, at the time of publication, the key 
sections of the protocol that are relevant to evaluating this study, such as sections describing the 
study objectives and hypotheses, the subject inclusion and exclusion criteria, the study design, 
outcomes, and procedures and the statistical analysis plan. Corbus will allow a medical journal 
editor to review the study database on request. 
Corbus will provide all investigators with the trial results and encourages investigators to share 
the results with the subjects in this study as appropriate. 

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Publication by the site of any data from this study must be carried out in accordance with the 
clinical trial agreement. Corbus maintains the right to be informed of any plans for publication 
and to review any resulting abstracts, presentations or manuscripts before they are submitted. 
The study database will be available to Corbus and relevant regulatory agencies as required. 

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12. 
APPENDICES  
Appendix 1 
Reproductive Potential and Highly Effective Methods of 
Contraception 
Appendix 2 
Investigator Global Assessment of Skin Activity 
Appendix 3 
Patient Improvement Questionnaire for Physicians  
Appendix 4 
Patient Improvement Questionnaire for Subjects  
Appendix 5 
Physician assessment of DM activity 
Appendix 6 
Algorithm to Calculate Total Improvement Score (TIS) 
Appendix 7 
Corticosteroid Conversion Table  
 
 
 

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APPENDIX 1. REPRODUCTIVE POTENTIAL AND ACCEPTABLE 
METHODS OF CONTRACEPTION4  
Women are considered to have “no childbearing potential” if they meet any of the following 
criteria:  
− Hysterectomy 
− Bilateral oophorectomy 
− Bilateral tubal ligation  
− Post-menopausal; menopause is defined as no menses for 12 months without an 
alternative medical cause, not using hormone contraception or hormonal 
replacement therapy. In women ≤ 55 years of age with no menses for ≥ 12 
months, FSH and LH levels should be measured to confirm postmenopausal state. 
Acceptable methods of contraception must be used by subjects who are women of child-bearing 
potential or their male sexual partners.  Acceptable methods of contraception must be used by 
subjects who are male or their female sexual partners of child-bearing potential. 
Acceptable and highly effective methods of contraception are those that result in a low failure 
rate (i.e., less than 1 percent per year) when used consistently and correctly. Examples of highly 
effective methods of contraception when used consistently and correctly include:  
− Combined (estrogen and progesterone containing) hormonal contraception 
associated with inhibition of ovulation  
 Oral 
 Intravaginal 
 Transdermal  
− Progesterone-only hormonal contraception associated with inhibition of ovulation  
 Oral 
 Injectable 
 Implantable 
− Intrauterine device  
− Intrauterine hormone-releasing system  
− Bilateral tubal occlusion  
− Vasectomized partner 
− Sexual abstinence. Abstinence is only acceptable when this is the preferred and 
usual lifestyle of the individual.  Periodic abstinence (calendar, symptothermal, 
post-ovulation methods), withdrawal (coitus interruptus) and lactational 
amenorrhea method are not acceptable means of contraception.  
Another acceptable method of contraception that is allowed in the study is: 
 Combination of condom and spermicide  
 
4 Acceptable contraceptive methods may not be available or approved in all countries; thus, the Sponsor does not 
restrict respective countries from excluding unavailable contraceptive methods in the ICF. 

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APPENDIX 5. PHYSICIAN ASSESSMENT OF DM ACTIVITY