Phase 3 Study of ASP015K - A Randomized, Double-blind, Placebo-controlled Confirmatory Study of the Safety and Efficacy of ASP015K in Patients With Rheumatoid Arthritis Who Had an Inadequate Response to DMARDs
Phase: PHASE3
Conditions: Rheumatoid Arthritis
Sponsor: Astellas Pharma Inc

Phase III Study of ASP015K
−A randomized, double-blind, placebo-controlled 
confirmatory study of the safety and efficacy of ASP015K 
in patients with rheumatoid arthritis (RA) who had an
inadequate response to DMARDs−
ISN/Protocol 015K-CL-RAJ3
ClinicalTrials.gov Identifier: NCT02308163
Date of Protocol: Version 5.0, dated 03 March 2017
Sponsor: Astellas Pharma Inc. (API)
2-5-1 Nihonbashi-Honcho, Chuo-ku, Tokyo

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 1 of 134 
 
 
 
Protocol for Phase III Study of ASP015K 
–A Randomized, Double-Blind, Placebo-Controlled Confirmatory Study of the Safety and 
Efficacy of ASP015K in Patients with Rheumatoid Arthritis (RA) who Had an Inadequate 
Response to DMARDs– 
 
 
 
Sponsor: 
Astellas Pharma Inc. (API) 
 
 
 
 
 
 
 
 
 
 
ISN/Protocol: 015K-CL-RAJ3 
 
Created 3 March 2017 (Ver. 5.0) 
 
This confidential document is the property of the sponsor. No unpublished information contained in this 
document may be disclosed without prior written approval of the sponsor. 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 2 of 134 
Table of Contents 
I. 
SIGNATURE ························································································ 8 
II. 
CONTACT DETAILS OF KEY SPONSOR’S PERSONNEL ····························· 9 
III. 
LIST OF ABBREVIATIONS AND DEFINITION OF KEY TERMS ·················· 11 
IV. 
SYNOPSIS  ······················································································· 16 
V. 
FLOW CHART AND SCHEDULE OF ASSESSMENTS ································· 30 
VI. 
ACCEPTABLE RANGE OF SCHEDULE OF ASSESSMENTS ························ 34 
1 
INTRODUCTION ················································································· 38 
1.1 
Background ···················································································· 38 
1.2 
Non-clinical and Clinical Data ······························································ 39 
1.2.1 
Nonclinical Pharmacology and Safety Pharmacology ······························ 39 
1.2.2 
Pharmacokinetics and Pharmacodynamics ··········································· 39 
1.2.2.1 
Nonclinical Pharmacokinetics ···················································· 39 
1.2.2.2 
Clinical Pharmacokinetics and Pharmacodynamics ··························· 40 
1.2.3 
Toxicology ··············································································· 43 
1.2.4 
Efficacy ··················································································· 43 
1.3 
Summary of Key Safety Information for Study Drugs ··································· 44 
1.4 
Risk-Benefit Assessment ····································································· 46 
2 
STUDY OBJECTIVE(S), DESIGN, AND VARIABLES ·································· 48 
2.1 
Study Objectives ·············································································· 48 
2.2 
Study Design and Dose Rationale ··························································· 48 
2.2.1 
Study Design ············································································· 48 
2.2.2 
Dose Rationale ··········································································· 49 
2.3 
Variables ······················································································· 51 
2.3.1 
Primary Variables ······································································· 51 
2.3.2 
Secondary Variables ···································································· 51 
2.3.2.1 
Secondary Efficacy Variables ···················································· 51 
2.3.2.2 
Safety Variables···································································· 52 
2.3.2.3 
Pharmacokinetics Variables ······················································ 52 
2.3.2.4 
Pharmacodynamics Variables ···················································· 52 
2.3.2.5 
Pharmacogenomics (Bio-Banking) [unique to Japan and Korea] ············ 52 
2.3.3 
Other Variables ·········································································· 52 
3 
STUDY POPULATION ·········································································· 53 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
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3.1 
Selection of Study Population ······························································· 53 
3.2 
Inclusion Criteria ·············································································· 53 
3.3 
Exclusion Criteria ············································································· 54 
3.4 
Discontinuation Criteria for Individual Subjects ·········································· 58 
3.4.1 
Suspension, Interruption, and Resumption of the Study Drug or Reference 
Drug ······················································································· 59 
3.4.1.1 
Criteria for Suspension or Interruption of the Study Drug or Reference 
Drug ················································································· 60 
4 
STUDY DRUGS OR REFERENCE DRUGS ················································ 61 
4.1 
Description of Study Drugs or Reference Drugs ·········································· 61 
4.1.1 
Test Drug(s) ·············································································· 61 
4.1.2 
Comparative Drug(s) ···································································· 61 
4.1.3 
Reference Drug(s) ······································································· 61 
4.2 
Packaging and Labeling ······································································ 62 
4.3 
Study/Reference Drug Handling ···························································· 63 
4.4 
Blinding ························································································ 63 
4.4.1 
Blinding Method ········································································· 63 
4.4.2 
Confirmation of the Indistinguishability of the Study Drugs ······················ 64 
4.4.3 
Retention of the Assignment Schedule and Procedures for Treatment Code 
Breaking ·················································································· 64 
4.4.4 
Breaking the Treatment Code for Emergency ······································· 64 
4.4.5 
Breaking the Treatment Code by the Sponsor ······································· 65 
4.5 
Assignment and Allocation ·································································· 65 
5 
TREATMENTS AND EVALUATION ························································ 66 
5.1 
Dosing and Administration of Study Drugs or Reference Drugs and Other 
Medications ···················································································· 66 
5.1.1 
Dose/Dose Regimen and Administration Period ···································· 66 
5.1.2 
Previous and Concomitant Medication (Drugs and Therapies) ···················· 67 
5.1.2.1 
Previous Medication (Drugs and Therapies) ··································· 68 
5.1.2.2 
Concomitant Medication (Drugs and Therapies) ······························ 72 
5.1.3 
Treatment Compliance ·································································· 75 
5.1.4 
Emergency Procedures and Management of Overdose ····························· 76 
5.1.5 
Criteria for Continuation of Treatment ··············································· 76 
5.1.6 
Compliance Rules to be Observed by Subjects throughout the Study ············ 76 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
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5.2 
Demographics and Baseline Characteristics ··············································· 77 
5.2.1 
Demographics ············································································ 77 
5.2.2 
Medical History ·········································································· 77 
5.2.3 
Diagnosis of the Target Disease, Severity, and Duration of Disease ·············· 78 
5.3 
Efficacy, Pharmacodynamics, and Pharmacokinetics Assessments ····················· 78 
5.3.1 
Efficacy Assessments ··································································· 78 
5.3.1.1 
Tender and Swollen Joint Counts ················································ 78 
5.3.1.2 
Assessment of Pain and Overall Assessment of Disease Activity ··········· 79 
5.3.1.3 
Acute Phase Reactants (CRP and ESR) ········································· 79 
5.3.1.4 
EULAR Response Criteria ······················································· 79 
5.3.1.5 
DAS28 ·············································································· 80 
5.3.1.6 
SDAI Score ········································································· 80 
5.3.1.7 
ACR Response Criteria Assessment ············································ 81 
5.3.1.8 
Patient Reported Outcomes/Assessments ······································· 81 
5.3.2 
Pharmacodynamic Assessments ······················································· 81 
5.3.2.1 
Lymphocyte Subsets ······························································ 81 
5.3.2.2 
Biomarkers for Efficacy and Safety Assessments ····························· 82 
5.3.3 
Pharmacokinetic Assessments ························································· 82 
5.4 
Safety Assessment ············································································ 82 
5.4.1 
Vital Signs ················································································ 82 
5.4.2 
Body Weight ············································································· 83 
5.4.3 
Adverse Events ·········································································· 83 
5.4.3.1 
Adverse Events of Possible Hepatic Origin ···································· 83 
5.4.4 
Laboratory Assessments ································································ 83 
5.4.4.1 
CPK Monitoring ··································································· 85 
5.4.4.2 
Hepatic Function Abnormal ······················································ 86 
5.4.5 
Physical Examination ··································································· 86 
5.4.6 
12-lead Electrocardiogram (ECG) ····················································· 86 
5.4.7 
Radiography ·············································································· 87 
5.4.8 
Central ECG ············································································· 87 
5.5 
Adverse Events and Other Safety Aspects ················································· 87 
5.5.1 
Definition of Adverse Events (AEs) ·················································· 87 
5.5.2 
Definition of Serious Adverse Events (SAEs) ······································· 88 
5.5.3 
Criteria for Causal Relationship to the Study Drug ································· 89 
5.5.4 
Criteria for Defining the Severity of an Adverse Event ···························· 89 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
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5.5.5 
Reporting of Serious Adverse Events (SAEs) ······································· 90 
5.5.6 
Follow-up of Adverse Events ·························································· 91 
5.5.7 
Procedure in Case of Pregnancy ······················································· 91 
5.5.8 
Supply of New Information Affecting the Conduct of the Study ·················· 92 
5.5.9 
Deviations from the Protocol and Other Actions Taken to Avoid 
Life-Threatening Risks to Subjects···················································· 93 
5.6 
Test Drug Concentration ····································································· 93 
5.7 
Other Measurements, Assessments, or Methods ·········································· 94 
5.7.1 
Pharmacodynamic Measurements ····················································· 94 
5.7.2 
Purposes of Pharmacogenomics ······················································· 94 
5.7.3 
Handling and Storage for Samples Used for Pharmacogenomics ················· 95 
5.7.4 
Disposal of Pharmacogenomics Samples ············································· 95 
5.7.5 
Disclosure of Genetic Information ···················································· 96 
5.8 
Total Amount of Blood ······································································· 96 
6 
TERMINATION OF THE CLINICAL STUDY ············································ 98 
7 
STATISTICAL METHODOLOGY ··························································· 99 
7.1 
Sample Size ···················································································· 99 
7.2 
Analysis Set ·················································································· 100 
7.2.1 
Full Analysis Set (FAS) ······························································ 100 
7.2.2 
Per Protocol Set (PPS) ································································ 100 
7.2.3 
Safety Analysis Set (SAF) ···························································· 101 
7.2.4 
Pharmacokinetic Analysis Set (PKAS) ············································· 101 
7.2.5 
Pharmacodynamics Analysis Set (PDAS) ·········································· 101 
7.3 
Demographics and Other Baseline Characteristics ······································ 101 
7.4 
Analysis of Efficacy ········································································ 101 
7.4.1 
Analysis of Primary Variable ························································ 101 
7.4.1.1 
Primary Analysis································································· 101 
7.4.1.2 
Secondary Analysis ······························································ 102 
7.4.1.3 
Subgroup Analysis ······························································· 102 
7.4.2 
Analysis of Secondary Variables ···················································· 102 
7.5 
Analysis of Safety ··········································································· 102 
7.5.1 
Adverse Events ········································································ 103 
7.5.2 
Laboratory Assessments ······························································ 103 
7.5.3 
Vital Signs ·············································································· 103 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
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7.5.4 
12-lead ECG ··········································································· 103 
7.5.5 
QT assessment ········································································· 103 
7.5.6 
Body Weight ··········································································· 103 
7.6 
Analysis of Pharmacokinetics ····························································· 103 
7.7 
Other Analyses ·············································································· 104 
7.7.1 
Analysis of Pharmacodynamics ····················································· 104 
7.7.2 
Analysis of Pharmacogenomics ····················································· 104 
7.8 
Interim Analysis (and Early Discontinuation of the Clinical Study) ·················· 104 
7.9 
Handling of Missing Data, Outliers, Visit Windows, and Other Information ······· 104 
7.9.1 
Handling of Schedule of Assessments of Efficacy Variables ···················· 104 
7.9.2 
Handling of Schedule of Assessments of Safety Variables ······················ 105 
7.9.3 
Handling of Schedule of Assessments of Pharmacodynamic Variables ········ 107 
7.9.4 
Handling of Schedule of Assessments of Pharmacokinetic Variables ·········· 108 
8 
OPERATIONAL AND ADMINISTRATIVE CONSIDERATIONS ·················· 109 
8.1 
Procedure for Clinical Study Quality Control ··········································· 109 
8.1.1 
Data Collection ········································································ 109 
8.1.2 
Specification of Source Documents ················································· 109 
8.1.3 
Clinical Study Monitoring ···························································· 110 
8.1.4 
Direct Access to Source Data/Documents ·········································· 110 
8.1.5 
Data Management ····································································· 111 
8.2 
Ethics and Protection of Subject Confidentiality ········································ 111 
8.2.1 
Institutional Review Board (IRB)/ Independent Ethic Committee (IEC) ······· 111 
8.2.2 
Ethical Conduct of the Study························································· 111 
8.2.3 
Informed Consent of Subjects ······················································· 111 
8.2.3.1 
Subject Information and Consent ·············································· 111 
8.2.3.2 
Subject Information and Consent for PGx Research ························ 112 
8.2.3.3 
Supply of New and Important Information Influencing the Subject’s 
Consent and Revision of the Written Information ··························· 112 
8.2.4 
Subject Confidentiality ······························································· 113 
8.3 
Administrative Matters ····································································· 113 
8.3.1 
Arrangement for Use of Information and Publication of the Clinical Study ··· 113 
8.3.2 
Documents and Records Related to the Clinical Study ··························· 114 
8.3.3 
Protocol Amendment and/or Revision ·············································· 116 
8.3.4 
Insurance of Subjects and Others ···················································· 116 
8.3.5 
Signatory Investigator for Clinical Study Report ·································· 117 

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9 
QUALITY ASSURANCE ······································································ 118 
10 
STUDY ORGANIZATION ···································································· 119 
10.1 
Independent Data and Safety Monitoring Board (DSMB) ····························· 119 
10.2 
Other Evaluation Committee(s) ··························································· 119 
10.3 
Other Study Organization ·································································· 119 
10.4 
Registration of Subjects ···································································· 120 
11 
REFERENCES ·················································································· 122 
12 
APPENDICES ··················································································· 125 
APPENDIX <1>: 
LIST OF PROHIBITED CONCOMITANT MEDICATION ········· 125 
APPENDIX <2>: 
LABORATORY TESTS ······················································ 126 
APPENDIX <3>: 
EVENTS ALWAYS CONSIDERED SERIOUS ························· 128 
APPENDIX <4>: 
LIVER SAFETY MONITORING AND ASSESSMENT ··············· 129 
APPENDIX <5>: 
1987 ACR CRITERIA FOR THE CLASSIFICATION OF RA······· 132 
APPENDIX <6>: 
2010 ACR-EULAR CLASSIFICATION CRITERIA FOR RA ······· 133 
APPENDIX <7>: 
CRITERIA FOR THE CLASSIFICATION OF GLOBAL 
FUNCTIONAL STATUS IN RA (1991 REVISED CRITERIA) ······················· 134 
APPENDIX <8>: 
CLASSIFICATION OF DISEASE STAGE/PROGRESSION OF 
RA 
134 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 8 of 134 
I. 
SIGNATURE 
AGREEMENT BETWEEN THE SPONSOR’S RESPONSIBLE PERSON AND THE 
INVESTIGATOR 
This clinical study will be conducted in adherence to GCP, ICH Guidelines and applicable 
laws and regulatory requirements, as well as this study protocol. As the evidence of the 
agreement, the investigator (CHIKEN SEKININ ISHI) and responsible person of the Sponsor 
(CHIKEN IRAI SEKININSHA) inscribe in the bipartite agreement. 
 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 9 of 134 
II. 
CONTACT DETAILS OF KEY SPONSOR’S PERSONNEL 
 
Contact Information for the Sponsor 
Corporate Name: 
 
 
Location: 
 
Phone No.: 
 
Fax: 
 
Sponsor’s personnel: 
 
[Contact numbers during non-business hours and for emergency]: 
 
 
 
Contact Information for the Contract Research Organization (CRO) 
 Japan 
Corporate name: 
 
 
Location: 
 
Phone No.: 
 
Fax: 
 
CRO’s personnel: 
 
[Contact numbers during non-business hours and for emergency]: 
 
 
 Korea 
Corporate name:
 
Location: 
 
Phone No.: 
 
Fax: 
 
CRO’s personnel: 
 
[Contact numbers during non-business hours and for emergency]: 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 10 of 134 
 
 
 Taiwan 
Corporate name: 
 
Location: 
 
Phone No.: 
 
Fax: 
 
CRO’s personnel: 
 
[Contact numbers during non-business hours and for emergency]: 
 
 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 11 of 134 
III. 
LIST OF ABBREVIATIONS AND DEFINITION OF KEY TERMS 
List of Abbreviations 
 
Abbreviations 
Description of abbreviations 
ACR 
American College of Rheumatology 
AE 
Adverse event 
ALP 
Alkaline phosphatase 
ALT 
Alanine aminotransferase (GPT) 
AST 
Aspartate aminotransferase (GOT) 
ASP015K 
Astellas Pharmaceuticals Compound 015K 
AUC 
Area under the plasma concentration–time curve 
AUCinf 
AUC from the time of dosing up to infinity with extrapolation of the 
terminal phase 
AUClast 
AUC from the time of dosing to the last measurable concentration 
BUN 
Blood urea nitrogen  
anti-CCP antibody  
anti-cyclic citrullinated peptide antibody 
Cmax 
Maximum concentration 
Ctrough 
Trough concentration 
CK/CPK 
Creatine kinase/creatine phosphokinase 
CK-MB 
Creatine kinase MB isozyme 
CRF 
Case report form 
CRO 
Contract research organization 
CRP 
C-reactive protein 
CYP 
Cytochrome P450 
DAS 
Disease activity score 
DIP 
Distal interphalangeal joint 
DILI 
Drug-induced liver injury 
DMARD 
Disease-modifying antirheumatic drug 
DNA 
Deoxyribonucleic acid 
DSMB 
Data and safety monitoring board 
ECG 
Electrocardiogram 
eCRF 
Electronic case report form 
EDC 
Electronic data capture 
EDTA 
Ethylenediaminetetraacetic acid 
ESR 
Erythrocyte sedimentation rate 
EU 
European Union 
EULAR 
European League Against Rheumatism 
FAS 
Full analysis set 
FDA 
Food and Drug Administration 
GCP 
Good Clinical Practice 
GFR 
Glomerular filtration rate 
GMP 
Good Manufacturing Practice 
γ-GTP 
γ-Glutamyl transpeptidase (GGT) 
HAQ-DI 
Health Assessment Questionnaire - Disability Index 
HBc antibody  
Hepatitis B core antibody 
HBs antigen/antibody Hepatitis B surface antigen/antibody 
HBV 
Hepatitis B virus 
HCV 
Hepatitis C virus 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 12 of 134 
Abbreviations 
Description of abbreviations 
HDL 
High-density lipoprotein 
hERG 
Ether-a-go-go related gene 
HIV 
Human immunodeficiency virus 
HSA 
Human serum albumin 
ICH 
International Conference on Harmonization of Technical Requirements for 
Registration of Pharmaceuticals for Human Use 
IEC 
Independent Ethic Committee 
IL 
Interleukin 
IND 
Investigational new drug 
INR 
International normalized ratio 
IP 
Interphalangeal joint 
IR 
Inadequate response 
IRB 
Institutional review board 
ISN 
International study number 
JAK 
Janus kinase 
LA-CRF 
Liver abnormality - CRF 
LC-MS 
Liquid chromatography- mass spectrometry 
LDL 
Low-density lipoprotein 
LOCF 
Last observation carried forward 
MCP 
Metacarpophalangeal joint 
MDRD 
Modification of diet in renal disease 
MedDRA 
Medical Dictionary for Regulatory Activities 
MMF 
Mycophenolate mofetil 
MMP-3 
Matrix metalloproteinase 3 
MPA 
Mycophenolic acid  
MPAG 
Mycophenolic acid glucuronide 
MTP 
Metatarsophalangeal joint 
MTX 
Methotrexate 
NCI-CTCAE 
National Cancer Institute Common Terminology Criteria for Adverse 
Events 
NDA 
New drug application 
NK 
Natural killer 
NOAEL 
No observed adverse effect level 
NSAIDs 
Non-steroidal anti-inflammatory drugs 
NYHA 
New York Heart Association 
PASI 
Psoriasis Area and Severity Index 
PD 
Pharmacodynamic 
PDAS 
Pharmacodynamic analysis set 
PGA 
Physician’s Global Assessment of Arthritis 
PGx 
Pharmacogenomics 
PIP 
Proximal interphalangeal joint 
PK 
Pharmacokinetic 
PKAS 
Pharmacokinetic analysis set 
PPS 
Per protocol set 
QOL 
Quality of life 
RA 
Rheumatoid arthritis 
RF 
Rheumatoid factor 
SAE 
Serious adverse event 
SAF 
Safety analysis set 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 13 of 134 
Abbreviations 
Description of abbreviations 
SDAI 
Simplified Disease Activity Index 
SF-36v2® 
Short Form Health Survey – 36 questions, version 2 
SFL 
Screening failure log 
SGA 
Subject’s Global Assessment of Arthritis 
SJC 
Swollen joint count 
SOP 
Standard operating procedure 
STAT5 
Signal transducers and activators of transcription 5 
SUSAR 
Suspected unexpected serious adverse reactions 
TBL 
Total bilirubin 
TEAE 
Treatment emergent adverse event 
TJC 
Tender joint count 
TNF 
Tumor necrosis factor 
t½ 
Apparent terminal elimination half-life 
tmax 
Time to attain Cmax 
TYK 
Tyrosine kinase 
ULN 
Upper limit of normal 
VAS 
Visual analog scale 
VEGF 
Vascular endothelial growth factor 
WBC 
White blood cell 
WPAI 
Work Productivity and Activity Impairment Questionnaire 
 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 14 of 134 
Definition of Key Study Terms 
 
Terms 
Definition of terms 
Adverse event 
An adverse event is defined as any untoward medical occurrence in a 
subject administered a study drug or reference drug that does not 
necessarily have a causal relationship with this treatment. 
Baseline 
1) Values/findings observed prior to the initiation of study treatment, 
which are regarded as the starting point for comparison. 
2) The time point at which those reference values/findings were observed. 
Study discontinuation 
The act of concluding participation, prior to completion of all 
protocol-required elements, in a study by an enrolled subject. Four 
categories of discontinuation are distinguished: a) dropout: Active 
discontinuation by a subject (also a noun referring to such a discontinued 
subject); b) discontinuation initiated by the investigator or other 
responsible personnel (e.g., for cause); c) loss to follow-up: 
discontinuation of participation without notice or action by the subject; d) 
sponsor-initiated discontinuation. 
Note that subject discontinuation does not necessarily imply exclusion of 
subject data from analysis. 
Enroll 
To register or enter into a clinical study; transitively and intransitively. 
Informed consent precedes enrollment, which precedes or is 
contemporaneous with randomization. 
Investigational period 
The period of time where major interests of protocol objectives are 
observed. In general, the subject will receive a test drug, comparative 
drug, or reference drug (possibly without randomization) during this 
period, which extends until the last post-treatment assessment is 
completed. 
Follow-up period 
The follow-up period will be 4 weeks (on a per-protocol basis) starting 
after the early-termination visit for withdrawn subjects and after the Week 
52 visit for subjects who completed the study but are not willing to enroll 
into the extension study or those in the reference group who completed the 
study. For subjects who completed the study and wish to enroll into the 
extension study, the follow-up period will last for a maximum of 4 weeks 
starting after the Week 52 visit and ending at the initiation of the extension 
study treatment. 
Randomization 
Action to allocate a subject to the treatment group or treatment cohort. 
Depending on the type of rules for handling for study drugs, 
‘Randomization’ is usually executed just before entering the 
‘investigational period.’ 
Screening 
1) Process of searching for candidates for the study 
2) Process of checking the eligibility of subjects, usually done during the 
“pre-investigational period” 
Screening failure 
Screened subject, but did not fulfill protocol inclusion and/or exclusion 
criteria and failed to receive randomized or open label study treatment, or 
decided not to participate anymore (withdrew consent) prior to completing 
pre-investigational period. 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 15 of 134 
Terms 
Definition of terms 
Serious adverse event 
Any adverse event that is judged “serious” by the 
investigator/sub-investigator or the sponsor and results in any of the 
following outcomes: death, a life-threatening condition, persistent or 
significant disability/incapacity or substantial disruption of the ability to 
conduct normal life functions, congenital anomaly/birth defect, 
hospitalization or prolongation of hospitalization, and other medically 
significant occurrences. 
Study period 
The period of time from obtaining informed consent from the subject to 
the end of the final evaluation/observation specified in the protocol. 
Subject 
An individual who participates in a clinical study as a recipient of either 
the test drug(s) or reference drug(s), or as a control. 
Subject ID 
A unique identifier code assigned to each subject signing the informed 
consent. 
Variable 
A characteristic under study that varies: any attribute, phenomenon, or 
event that can have different qualitative or quantitative values. 
 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 16 of 134 
IV. 
SYNOPSIS 
Title of Study: 
Phase III Study of ASP015K 
–A randomized, double-blind, placebo-controlled confirmatory study of the 
safety and efficacy of ASP015K in patients with rheumatoid arthritis (RA) who 
had an inadequate response to DMARDs– 
(Protocol No.: 015K-CL-RAJ3) 
Planned Study Period: 
From July 2014 to December 2017 
Study Objectives: 
The objectives of the study are as follows: 
To verify the superiority of ASP015K alone or in combination with 
disease-modifying antirheumatic drugs (DMARDs) over placebo in terms of 
efficacy, at doses of 100 mg/day and 150 mg/day, in patients with rheumatoid 
arthritis (RA) who had an inadequate response to DMARDs, as measured by 
the ACR20 response rate at Week 12, which is the primary variable; 
To evaluate the pharmacokinetics, pharmacodynamics, and safety of 
ASP015K; 
To evaluate the efficacy and safety of long-term treatment with ASP015K (52 
weeks); and 
To use open-label etanercept, an existing anti-TNF agent, as the reference 
drug. 
Planned Total Number of 
Study Centers and 
Locations: 
Approximately 160 centers 
Japan, Korea, and Taiwan 
Design and Methodology: 
This is a multi-center, randomized, placebo-controlled, double-blind, 
parallel-group, confirmatory study to evaluate the efficacy and safety of 
ASP015K alone or in combination with DMARDs, at doses of 100 mg and 
150 mg, in patients with RA who had an inadequate response to DMARDs. 
Etanercept will also be administered as the reference drug. In the study, 
ASP015K (test drug) and placebo (comparative drug) will be given as study 
drugs, and etanercept will be given as a separate reference drug. After 
screening, subjects will be randomized at baseline in a 1:1:1:2 ratio to the 
ASP015K 100 mg group, ASP015K 150 mg group, placebo group, or reference 
group in each study region. The study drug will be orally administered once 
daily (QD) after breakfast for 52 weeks. Etanercept will be administered 
subcutaneously once weekly for 52 weeks (the last dose will be given at Week 
51). At Week 12, subjects in the placebo group will be switched to either 
ASP015K 100 mg or ASP015K 150 mg, and the dose will be maintained until 
the end of treatment. The dose of ASP015K (100 or 150 mg) to be started at 
Week 12 for the placebo group will be determined randomly at baseline in 
advance and switched in a blinded manner. 
Dynamic allocation procedures in each study region (Japan, Korea and 
Taiwan) will be used at randomization at baseline, with the study center, prior 
biologic-DMARD-IR, and concomitant DMARD use at the initiation of 
treatment with the study drug or reference drug as covariates. 
An anti-TNF agent, etanercept, will be administered as the reference drug in an 
open-label manner. 
Subjects in the ASP015K 100 mg, ASP015K 150 mg, or placebo groups who 
have completed the study will be eligible for participation in an open-label 
extension study (015K-CL-RAJ2). Subjects will make a follow-up visit after 
the Week 52 visit if they do not enroll into the extension study on the day of 
the Week 52 visit. 
Number of Subjects to Be 
Enrolled/Randomized: 
One-hundred subjects per group will receive the study drug and 200 subjects 
the reference drug (a total of 500 subjects). 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 17 of 134 
Inclusion/Exclusion 
Criteria: 
<Inclusion Criteria> 
Subject is eligible for the study if all of the following apply: 
1. Subject has received a full explanation of the study drug and this study in 
advance, and written informed consent to participate in the study has been 
obtained from the subject himself/herself. 
2. Subject is a man or woman aged ≥ 20 years at the time of informed consent. 
3. Subject has RA diagnosed according to the 1987 American College of 
Rheumatology (ACR) criteria or the 2010 American College of 
Rheumatology/European League against Rheumatism (ACR/EULAR) 
criteria. 
4. Subject who did not receive the following drugs, or received the drugs with 
stable dosage for at least 28 days prior to the baseline (start of treatment) 
for RA treatment: 
Non-steroidal anti-inflammatory drugs (NSAIDs; excluding topical 
formulations), oral morphine or equivalent opioid analgesics 
(≤ 30 mg/day), acetaminophen, or oral corticosteroids (≤ 10 mg/day in 
prednisolone equivalent). 
5. At screening subject has active RA as evidenced by both of the following: 
• ≥ 6 tender/painful joints (using 68-joint assessment) 
• ≥ 6 swollen joints (using 66-joint assessment) 
6. CRP > 0.50 mg/dL at screening 
7. Subject meets the ACR 1991 Revised Criteria for the Classification of 
Global Functional Status in RA Class I, II, or III at screening. 
8. Inadequate responder to (including subjects who were intolerant of) at least 
one DMARD administered for at least 90 days prior to screening 
9. When the following DMARDs are concomitantly administered to subject, 
the drugs must be administered for at least 90 days prior to screening, and 
must be stable from at least 28 days prior to screening until the end of the 
administration period of study drug or reference drug. 
 
● 
Methotrexate (MTX) 
● 
Hydroxychloroquine 
● 
Salazosulfapyridine 
● 
Gold 
● 
D-penicillamine 
● 
Lobenzarit 
● 
Actarit 
● 
Bucillamine 
● 
Iguratimod 
 
10. Subject must be willing and able to comply with the study requirements. 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 18 of 134 
Inclusion/Exclusion 
Criteria: 
<Exclusion Criteria> 
Subject will be excluded from participation if any of the following applies: 
1. Subject has received a biologic DMARD within the specified period: 
• Anakinra: within 28 days prior to baseline 
• Adalimumab, infliximab: within 56 days prior to baseline 
• Golimumab, certolizumab pegol: within 70 days prior to baseline 
• Abatacept, tocilizumab: within 84 days prior to baseline 
• Denosumab: within 150 days prior to baseline 
• Rituximab: within 180 days prior to baseline 
2. Subject has received etanercept. 
3. Inadequate responder to at least 3 biologic DMARDs as determined by 
investigator/sub-investigator. 
4. Subject has received a non-biologic DMARD listed below or other drugs 
used in the treatment of RA within 28 days prior to baseline. Leflunomide 
is prohibited within 180 days prior to baseline. Alternatively, leflunomide is 
prohibited within 28 days prior to baseline if washout with cholestyramine 
for at least 17 days is completed at least 28 days prior to baseline. However, 
topical drugs other than those for the treatment of RA may be used 
concomitantly. 
• Leflunomide 
• Tacrolimus 
• Cyclosporine 
• Cyclophosphamide 
• Azathioprine 
• Minocycline 
• Mizoribine 
5. Subject has received tofacitinib or other JAK inhibitor (including other 
investigational drugs). 
6. Subject has received intra-articular, intravenous, intramuscular, or 
endorectal (excluding suppositories for anal diseases) corticosteroid within 
28 days prior to baseline. 
7. Subject has participated in any study of ASP015K and has received 
ASP015K or placebo. 
8. Subject has received other investigational drugs within 90 days or within 5 
half-lives, whichever is longer, prior to baseline. 
9. Subject has received plasma exchange therapy within 60 days prior to 
baseline. 
10. Subject has undergone joint drainage, has received local anesthesia and 
nerve block, or has received articular cartilage protectant at the assessed 
joint within 28 days prior to baseline. 
11. Subject has undergone surgery and has residual effects in the assessed 
joints at the discretion of investigator/sub-investigator, or is scheduled to 
undergo surgery that may affect the study evaluation of the assessed joints 
at the discretion of investigator/sub-investigator. 
12. A diagnosis of inflammatory arthritis (psoriatic arthritis, ankylosing 
spondylitis, SLE, sarcoidosis, etc.) other than RA. 
13. Any of the following laboratory values during the screening test period: 
• Hemoglobin < 9.0 g/dL 
• Absolute neutrophil count < 1000/µL 
• Absolute lymphocyte count < 800/µL 
• Platelet count < 75000/µL 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 19 of 134 
Inclusion/Exclusion 
Criteria: 
• ALT ≥ 2 ×ULN 
• AST ≥ 2 × ULN  
• Total bilirubin (TBL) ≥ 1.5 × ULN 
• Estimated GFR ≤ 40 mL/min as measured by the MDRD method 
• β-D-glucan > ULN [in case of Japan: ≥ 11 pg/mL] 
• Positive HBs antigen, HBc antibody, HBs antibody, or HBV-DNA 
quantitation (However, subject with negative HBs antigen and 
HBV-DNA quantitation, and positive HBc antibody and/or HBs 
antibody is eligible if HBV-DNA is monitored by HBV-DNA 
quantitation at every scheduled visit after initiation of study drug or 
reference drug administration.) 
• Positive HCV antibody 
14. Subject has a history of or concurrent active tuberculosis (TB). Eligibility 
criteria for TB are tabulated below:  
History of 
active TB 
Chest x-ray (for TB) 
TB 
infectionb) 
Exposure to 
patients 
with 
infective TB 
(interview) 
Eligibility 
Present 
- 
- 
- 
Not eligible 
Absent 
Abnormal (active) 
- 
- 
Not eligible 
Abnormal (old)a) 
- 
Eligible 
Eligible if  
prophylaxis is 
givenc) 
Normal 
Positive 
Eligible 
Eligible if  
prophylaxis is 
givenc) 
Negative 
Exposed 
Eligible if  
prophylaxis is 
givenc) 
Not exposed 
Eligible 
a) Old TB is evidenced if chest x-ray reveals pleural thickening, band-like shadow, and 
calcification ≥ 5 mm. Chest x-ray within 90 days prior to baseline may substitute the screening test. 
b) T-spot or Quantiferon Gold test is of first priority. When the result is equivocal or invalid, retest 
including other test methods may be allowed. If a retest is not performed, criteria for positive 
results will be followed. When T-spot or Quantiferon Gold test is not feasible, tuberculin test will 
be performed. Tuberculin is defined as positive with a red spot covering an area of 20 mm or more 
or induration. Tests conducted within 90 days prior to baseline may be used for diagnosis. 
c) Subject must receive or have received prophylaxis with isoniazid or rifampicin. Prophylaxis will 
be administered for 6 to 9 months, starting from at least 21 days prior to baseline. 
15. Subject meets any of the following in terms of infections except for TB: 
• History of or concurrent severe herpes zoster (associated with Hunt 
syndrome or having ulcerative lesions) or disseminated herpes zoster 
• History of multiple recurrences (at least twice) of localized herpes zoster 
• Serious infection requiring hospitalization within 90 days prior to 
baseline 
• Subject has received intravenous antibiotics within 90 days prior to 
baseline. (However, prophylactic antibiotics are allowed.) 
• Subject with high risk of infection (e.g., subject with urinary catheter) at 
the discretion of investigator/sub-investigator 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 20 of 134 
Inclusion/Exclusion 
Criteria: 
16. Subject has a history of or concurrent interstitial pneumonia and 
investigator/sub-investigator judges that it is inappropriate for the subject to 
participate in this study. 
17. Subject has a history of or concurrent malignant tumor (except for 
successfully treated basal cell carcinoma). 
18. Subject has received live or live attenuated virus vaccination within 56 days 
prior to baseline. (Inactivated vaccines including influenza and 
pneumococcal vaccines are allowed.) 
19. Subject has a history of or concurrent demyelinating disorders. 
20. Subject has any ongoing severe, progressive, or uncontrolled renal, hepatic, 
hematological, gastrointestinal, metabolic, endocrine, pulmonary, cardiac, 
neurological, infectious, or autoimmune disease except for RA (excluding 
Sjogren’s syndrome and chronic thyroiditis), or any ongoing illness which 
would make the subject unsuitable for the study as determined by the 
investigator/sub-investigator. 
21. Subject has a history of clinically significant allergy. (Clinically significant 
allergy includes allergies such as systemic urticaria induced by specific 
antigens and drugs, anaphylaxis, and allergy associated with shock 
necessitating hospitalized treatment.) 
22. Subject has received medications that are CYP3A substrates with narrow 
therapeutic range within 14 days prior to baseline. These medications 
include: dihydroergotamine, ergotamine, fentanyl, pimozide, quinidine, 
temsirolimus, and disopyramide. 
23. Subject has concurrent cardiac failure, defined as NYHA classification 
Class III or higher, or a history of it. 
24. Subject has concurrent prolonged QT syndrome or a history of it. Subject 
has prolonged QT interval (defined as QTc ≥ 500 msec. Subject has QTc 
≥ 500 msec at retest will be excluded) at screening. 
25. Subject has a history of positive HIV infection. 
26. Subject is a woman who is pregnant or might be pregnant, is nursing, 
wishes to conceive for a period running from the time informed consent is 
given within 60 days after end of treatment (including reference drug), or 
for whom the possibility of pregnancy cannot be ruled out as a result of the 
serum pregnancy test given at the time of screening. 
27. Subject is a man who cannot practice at least 2 types of contraception from 
the time of informed consent to 90 days after end of treatment (including 
reference drug), or subject is a woman with childbearing potential who 
cannot practice at least 2 types of contraception from the time of informed 
consent to 60 days after end of treatment (including reference drug). 
28. Male subject who do not agree not to donate sperm starting at informed 
consent and through the treatment period and for at least 90 days after final 
study drug (or reference drug) administration. Female subject who do not 
agree not to donate ova starting at informed consent through the treatment 
period and for 60 days after final study drug (or reference drug) 
administration. 
29. The subject has been judged unsuitable to participate in the study for other 
reasons by the investigator/sub-investigator. 
30. The subject has a history or complication of lymphatic diseases such as 
lymphoproliferative disorder, lymphoma, and leukemia. 
31. Subject has congenital short QT syndrome or a history of it. Subject has 
shortened QT interval (defined as QTc < 330 msec. Subject has QTc < 330 
msec at retest will be excluded) at screening. 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 21 of 134 
Discontinuation Criteria: 
The investigator/sub-investigator should discontinue the study if any of the 
following occurs: 
 
1. The subject withdraws consent. 
2. The investigator/sub-investigator judges that the study drug or reference 
drug is not sufficiently effective and the treatment method needs to be 
changed. 
3. Symptomatic CPK elevation (> 1.5 × ULN accompanied with severe and 
unusual episodes of myalgia, muscular weakness, or muscle twitching). 
4. Any case of myopathy involving severe and unusual episodes of myalgia, 
muscular weakness, or muscle twitching that persists for no less than, or 
aggravates rapidly within, 2 weeks, regardless of the CPK level. 
5. A previously HBV-infected patient with positive HBc antibody, positive 
HBs antibody, or both has been shown positive for HBV-DNA during the 
study. 
Attention should be paid that abrupt discontinuation of immunotherapy 
may cause fulminant or severe liver failure. Therefore, if the subject 
manifests HBV reactivation, the investigator/sub-investigator will 
administer nucleoside analogs without delay [unique to Japan: according to 
the “Proposal for Management of Rheumatic Disease Patients with 
Hepatitis B Virus Infection Receiving Immunosuppressive Therapy” (Japan 
College of Rheumatology)]. The investigator/sub-investigator will carefully 
decide whether to continue or discontinue the study drug, reference drug, 
and concomitant DMARDs in consultation with the hepatology specialist. 
6. Malignant tumor 
7. The subject develops a serious infection or other adverse events (AEs), and 
continued administration of the study drug is not deemed appropriate in the 
subject’s best interest by the investigator/sub-investigator. 
8. The subject has been treated with a prohibited concomitant drug or therapy 
(including another investigational product) that may impact efficacy 
evaluation. The subject has been, or needs to be, treated with a rescue 
medication for a period extending beyond its allowable time. Otherwise, the 
subject has been, or needs to be, treated with a live or live attenuated 
vaccine. 
9. The subject has been judged by the investigator/sub-investigator to be 
non-compliant to the medication requirements for treatment with the study 
drug, concomitant DMARDs, or reference drug injection. 
10. The subject is deemed incapable of continuing the follow-up based on the 
opinion of the investigator/sub-investigator (subject can no longer come to 
the study center; subject can no longer be contacted, etc.). 
11. It comes to light after the administration of the first dose of study drug or 
reference drug that inclusion criteria were not met at the time of case 
enrollment or that criteria for exclusion were met. It comes to light that 
there was some other major deviation from the protocol. 
12. The subject needs the study drug or reference drug to be interrupted beyond 
its allowable time limit. 
13. Investigator/sub-investigator decides it is in the subject’s best interest. 
14. The sponsor has requested that the study be discontinued because of a 
safety concern in a particular subject, or the sponsor has decided to 
discontinue the study altogether. 
15. The Subject shows QTc interval < 300 msec at central ECG, or the subject 
shows QTc interval < 300 msec at the study site’s ECG and also shows 
QTc interval < 300 msec at retest of study site’s ECG. 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 22 of 134 
Suspension, Interruption, 
and Resumption of the 
Study Drug or Reference 
Drug: 
During treatment with the study drug or reference drug, if the subject meets 
any of the criteria provided in “Criteria for Suspension or Interruption of the 
Study Drug or Reference Drug,” the investigator/sub-investigator will 
immediately suspend or interrupt the study drug or reference drug. The 
investigator/sub-investigator can resume treatment with the study drug or 
reference drug only if re-examinations and other assessments performed after 
the suspension or interruption confirm that none of the conditions listed below 
are applicable to the subject and the investigator/sub-investigator considers it 
desirable for the interest of the subject on the basis of risk-benefit analysis. 
 
The maximum allowable time for “suspension” is 7 days for the study drug and 
a week (1 dose per week) for the reference drug. If the treatment is halted 
beyond the suspension period, i.e., longer than 7 days for the study drug or 
skipping more than 1 dose for the reference drug, the period of no treatment is 
categorized as an “interruption.” 
Upper limits have been set to the number of interruptions 1 subject can have 
and to the duration of 1 interruption. One interruption period may last for 28 
days for the study drug and 4 weeks (i.e., 4 consecutive doses) for the reference 
drug. One subject is allowed to have a maximum of 2 interruptions, which 
must be separated by 16 or more weeks. 
The investigator will consult the sponsor regarding the handling of a subject 
who repeatedly requires treatment suspension. 
The subject must be withdrawn from the study, if he or she requires either a 
third interruption or a second interruption within less than 16 weeks from the 
first one. 
 
Criteria for Suspension or Interruption of the Study Drug or Reference Drug 
The investigator/sub-investigator will suspend or interrupt the study drug or 
reference drug if any of the following becomes applicable during treatment 
with the study drug or reference drug: 
 
1. Clinical laboratory tests yielded any of the following results: 
• Hemoglobin < 8.0 g/dL 
• Absolute neutrophil count < 500/µL 
• Absolute lymphocyte count < 500/µL 
• Platelet count < 50000/µL 
• Creatinine (serum) levels measured at 2 consecutive hospital visits: 
above 150% of the baseline level 
• CPK > 10 × ULN 
2. β-D-glucan > ULN [in case of Japan: ≥ 11 pg/mL] 
3. The subject requires a medication whose concomitant administration is 
prohibited in the protocol because of possible drug-drug interaction. 
4. The subject is suspected to be pregnant. 
5. The investigator/sub-investigator judged it appropriate in the interest of the 
subject to suspend or interrupt the study drug or reference drug. 
6. The sponsor made a request to suspend or interrupt the study drug or 
reference drug out of safety concerns for the subject. 
Participation in an 
Open-Label Extension 
Study: 
Subjects in the ASP015K 100 mg group, ASP015K 150 mg group, or placebo 
group who have completed the study will be eligible for participation in the 
open-label extension study (Protocol No.: 015K-CL-RAJ2). 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 23 of 134 
Test Drugs: 
Mode of Administration: 
Dose: 
Duration of Treatment: 
Test drugs: ASP015K 100 mg and 150 mg tablets 
Dose: 100 mg/day, 150 mg/day 
Mode of administration: To be orally administered QD after breakfast. The first 
dose should be given at each study center on the day 
of the baseline visit after all the necessary assessments 
and tests have been completed. 
Duration of treatment: 52 weeks 
Comparative Drugs: 
Mode of Administration: 
Dose: 
Duration of Treatment: 
ASP015K placebo tablets 
Mode of administration: To be orally administered QD after breakfast. The first 
dose should be given at each study center on the day 
of the baseline visit after all the necessary assessments 
and tests have been completed. 
Duration of treatment: 52 weeks (placebo will be administered for a 
maximum of 12 weeks. Subjects in the placebo group 
will be switched to either ASP015K 100 mg or 
ASP015K 150 mg at Week 12.) 
Reference Drugs: 
Mode of Administration: 
Dose: 
Duration of Treatment: 
Etanercept: 50 mg for subcutaneous injection, syringe: 1.0 mL 
Mode of administration: To be subcutaneously administered once weekly. The 
first dose should be given at each study center on the 
day of the baseline visit after all the necessary 
assessments and tests have been completed. 
Subsequent doses may be given at the study center or 
self-administered. Subjects who receive etanercept at 
the study center will be required to visit the site in 
addition to the scheduled visits. 
Duration of treatment: 52 weeks (the last dose will be given at Week 51) 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 24 of 134 
Concomitant 
Medication: 
1) Prohibited concomitant medications and therapies 
● Biologic DMARDs 
Administration of the biologic DMARDs below will be prohibited for a 
specified period of time (stated below) and during treatment with the study 
drug or reference drug. Etanercept given as the reference drug will be 
excluded. 
 Etanercept: after informed consent is obtained 
 Anakinra: within 28 days prior to baseline 
 Adalimumab, infliximab: within 56 days prior to baseline 
 Golimumab, certolizumab pegol: within 70 days prior to baseline 
 Abatacept, tocilizumab: within 84 days prior to baseline 
 Denosumab: within 150 days prior to baseline 
 Rituximab: within 180 days prior to baseline 
 
● Non-biologic DMARDs 
Administration of non-biologic DMARDs other than those listed below will 
be prohibited within 28 days prior to baseline and during treatment with the 
study drug or reference drug. 
Subjects who continue receiving the drugs described below during 
treatment with the study drug or reference drug should follow regulations 
for restricted concomitant medications. 
The use of leflunomide is prohibited within 180 days prior to baseline. 
However, if washout with cholestyramine for at least 17 days is completed 
before 28 days prior to baseline, the use of leflunomide will be prohibited 
within 28 days prior to baseline and during treatment with the study drug or 
reference drug. 
When subjects discontinue receiving the drugs listed below before the 
initiation of treatment with the study drug or reference drug, their use will 
be prohibited within 28 days prior to baseline and during treatment with the 
study drug or reference drug. However, topical drugs other than those for 
the treatment of RA may be used concomitantly. 
 
 Methotrexate (MTX) 
 Hydroxychloroquine 
 Salazosulfapyridine 
 Gold 
 D-penicillamine 
 Lobenzarit 
 Actarit 
 Bucillamine 
 Iguratimod 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 25 of 134 
Concomitant 
Medication: 
● Other drugs to be used in the treatment of RA 
Cyclosporine, cyclophosphamide, azathioprine, minocycline, and other 
drugs indicated for the treatment of RA will be prohibited within 28 days 
prior to baseline and during treatment with the study drug or reference 
drug. 
● Corticosteroids 
Oral corticosteroids at doses exceeding 10 mg per day in the prednisolone 
equivalent will be prohibited within 28 days prior to baseline and during 
treatment with the study drug or reference drug. 
The intra-articular, intravenous, intramuscular, and endorectal 
corticosteroid administration will also be prohibited within 28 days prior to 
baseline and during treatment with the study drug or reference drug. 
However, suppositories for anal diseases may be used concomitantly. 
● Oral morphine 
Oral morphine at doses exceeding 30 mg per day (or equivalent doses of 
other opioid analgesics) will be prohibited within 28 days prior to baseline 
and during treatment with the study drug or reference drug. 
● Other study drugs 
Other study drugs will be prohibited within 90 days or 5 half-lives, 
whichever is longer, prior to baseline. In addition, the use of other study 
drugs will be prohibited during the study period. 
● CYP3A substrates 
The following CYP3A substrate drugs with a narrow therapeutic range will 
be prohibited within 14 days prior to baseline, during treatment with the 
study drug or reference drug, and during the follow-up period: 
dihydroergotamine, ergotamine, fentanyl, pimozide, quinidine, 
temsirolimus, disopyramide, etc. 
● Vaccines 
Live or live attenuated vaccinations will be prohibited within 56 days prior 
to baseline, during treatment with the study drug or reference drug, and 
during the follow-up period. Inactivated vaccines may be administered 
(influenza, pneumococcal vaccines, etc.). 
● Plasma exchange therapy 
Plasma exchange therapy will be prohibited within 60 days prior to baseline 
and during treatment with the study drug or reference drug. 
● Surgical treatment methods 
Surgery involving the target joint will be prohibited from the time of 
informed consent to the end of treatment with the study drug or reference 
drug. 
● Effusion drainage, local anesthesia, and nerve block of the target joint 
Effusion drainage, local anesthesia, and nerve block of the target joint will 
be prohibited within 28 days prior to baseline and during treatment with the 
study drug or reference drug. 
● Articular cartilage protective agents 
The use of articular cartilage protective agents in the target joint will be 
prohibited within 28 days prior to baseline and during treatment with the 
study drug or reference drug. 
2) Restricted concomitant medications 
<Concomitant DMARDs> 
● If any (some) of the following DMARDs are administered concomitantly 
with the study drug or reference drug, they should be given for at least 90 
days prior to screening, and the same dosage and administration schedule 
must be maintained from at least 28 days prior to screening to the end of 
treatment with the study drug or reference drug. 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 26 of 134 
Concomitant 
Medication: 
● Changes to the dosage, administration schedule, or route of administration 
will not be allowed within 28 days prior to baseline and during treatment 
with the study drug or reference drug. 
● If a DMARD is temporarily interrupted or its dose is reduced within 28 
days prior to the baseline visit in a subject eligible at screening for the study 
based on inclusion and exclusion criteria, the screening period will be 
extended to allow for the same dosage and administration schedule to be 
observed for 28 days prior to the baseline visit. 
● In the case of AEs, administration may be temporarily interrupted, or the 
dose may be temporarily reduced. When resuming administration, the 
baseline dose is the upper limit. The period of interruption is up to 28 days 
and interruption is allowed only once. 
● If MTX is administered with study drug or reference drug concurrently, the 
concomitant use of folic acid should be considered whenever possible. The 
dose of folic acid during the study period will, in principle, be within 10 mg 
per week, but it may be adjusted. If MTX is administered and ALT/AST 
becomes ≥ 3 × ULN, MTX must be interrupted, or the dose must be 
reduced, and daily administration of folic acid should be considered. 
 
 Methotrexate (MTX) 
 Hydroxychloroquine 
 Salazosulfapyridine 
 Gold 
 D-penicillamine 
 Lobenzarit 
 Actarit 
 Bucillamine 
 Iguratimod 
 
<Other restricted concomitant medications> 
Regarding the drugs listed below, changes to the dosage, administration 
schedule, or route of administration will not be allowed within 28 days prior to 
baseline and during treatment with the study drug or reference drug, unless the 
specific conditions for the change are met. 
● The drugs listed below will be prohibited within 28 days prior to baseline 
and during treatment with the study drug or reference drug if they are to be 
discontinued before the initiation of treatment with the study drug or 
reference drug [except in cases where NSAIDs and non-NSAID analgesics 
(e.g., acetaminophen, opioid analgesics, all-in-one flu and cold 
medications) are used as rescue medication]. 
● In the case of AEs, administration of drugs below may be temporarily 
interrupted, or the dose may be temporarily reduced. The period of 
interruption is up to 28 days. When resuming administration, the baseline 
dose is the upper limit. 
● During treatment with the study drug or reference drug from Week 12, the 
drugs below may be discontinued, new drugs may be used, and the dosage, 
administration schedule, or route of administration of the concomitant 
drugs may be changed. However, with the exception of oral corticosteroids, 
after changing the conditions, administration must be continued under the 
same conditions for 12 weeks or longer. 
 
 NSAIDs (excluding topical drugs) 
 Oral morphine (not more than 30 mg per day, or equivalent doses of 
other opioid analgesics) 
 Acetaminophen 
 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 27 of 134 
Concomitant 
Medication: 
 Oral corticosteroids (however, at 10 mg per day or less in the 
prednisolone equivalent and from the visit at Week 12, the dose may be 
reduced or increased within the range not exceeding the baseline dose.) 
 
3) Rescue medications 
The drugs listed below may be administered only if they are necessary for 
treating an untoward medical occurrence, AEs, comorbid conditions, or 
acute aggravation of the primary disease within 28 days prior to baseline 
and during treatment with the study drug or reference drug. However, these 
medications may not be taken within 24 hours before joint assessment at 
each visit. 
 NSAIDs: For 3 days or less 
 Analgesics other than NSAIDs (acetaminophen, opioid analgesics, 
all-in-one flu and cold medications, etc.): For 7 consecutive days or less 
Major Outcome 
Variables 
Efficacy 
<Primary Variables> 
ACR20 response rate at Week 12 
<Secondary Variables> 
● ACR20 response rate 
● ACR50 response rate 
● ACR70 response rate 
● Change from baseline in DAS28-CRP and DAS28-ESR scores 
● Change from baseline in Tender Joint Count (TJC) (68 joints) 
● Change from baseline in Swollen Joint Count (SJC) (66 joints) 
● Percentage of subjects achieving DAS28-CRP and DAS28-ESR scores for 
remission 
● Percentage of subjects achieving low disease activity by DAS28-CRP and 
DAS28-ESR 
● Change from baseline in CRP and ESR 
● Percentage of subjects with good EULAR response 
● Percentage of subjects with good or moderate EULAR response 
● Percentage of subjects achieving ACR/EULAR remission 
If all of the following 4 parameters are fulfilled, it is defined as remission: 
 TJC ≤ 1 
 SJC ≤ 1 
 CRP ≤ 1 mg/dL 
 Subject’s Global Assessment of Arthritis (SGA) ≤ 1 cm (on a VAS of 
0–100 mm) 
● Percentage of subjects achieving SDAI remission (SDAI score ≤ 3.3) 
● Change from baseline in SDAI score 
● Change from baseline in Physician’s Global Assessment of Arthritis (PGA) 
(VAS) 
● Change from baseline in SGA (VAS) 
● Change from baseline in subject’s assessment of pain (VAS) 
● Incidence of subject withdrawal due to the lack of efficacy 
● Change from baseline in HAQ-DI score 
● Change from baseline in SF-36v2® score 
● Change from baseline in WPAI score 
Variables 
(Safety): 
● AEs 
● Vital signs (body temperature, pulse rate, and blood pressure in a sitting 
position) 
● Body weight 
● 12-lead electrocardiogram (ECG) 
● Central electrocardiogram 
● Chest radiography 
● Laboratory assessments 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 28 of 134 
Variables 
(Pharmacokinetics): 
● Plasma ASP015K concentration on each day of the study visit 
Variables 
(Pharmacodynamics): 
● Change from baseline in VEGF level 
● Change from baseline in MMP-3 level 
● Change from baseline in lymphocyte subset assays (CD3, CD4, CD8, 
CD16, CD19, CD56, CD56/16) 
 
Additional analysis may be performed for biomarkers for efficacy and safety 
assessments based on study results using blood samples that have been 
collected during the study and biobanked (i.e., residual sample stored for 
retrospective analysis). These could include biomarkers of inflammation, bone 
or cartilage metabolism, or inhibitory activity of JAK, but other biomarkers 
may also be subject to analysis. 
Pharmacogenomics 
(Bio-Banking): 
[Unique to Japan and Korea: To prepare for future research to analyze the 
relationship between genes and the efficacy, safety, or pharmacokinetics of the 
study drug, blood samples will be collected and stored with the consent of the 
subject in Japan and Korea.]  
Statistical Methods: 
[Target Sample Size Calculation] 
The target sample size for placebo and each ASP015K treatment group was set 
at 100 subjects. The target sample size for the reference group was set at 200 
subjects. 
Based on 015K-CL-RAJ1 result and efficacy result from other RA drugs 
[XELJANZ®, tablet, 5 mg, CTD (2013)] [CIMZIA, sc, 200 mg, Syringe, CTD 
(2012)], 62 subjects per group will provide 90% power to detect a difference 
assumed in the Step 2 in the closed testing procedure (described in Primary 
Efficacy Variable Analysis) under the following assumptions. In addition, it is 
assumed that ACR20 response rate of each region is similar: 
o ACR 20% response rate at Week12 in the placebo group: 25% 
o ACR 20% response rate at Week12 in the ASP015K 100 mg group: 54.5% 
o ACR 20% response rate at Week12 in the ASP015K 150 mg group: 65.5% 
o Two-sided significance level of 0.05 
 
On the other hand, according to the Extent of Population Exposure to Assess 
Clinical Safety for Drugs Intended for Long-term Treatment of 
Non-life-threatening Conditions (PAB/PCD Notification No. 592, dated 24 
May 1995) (“the long-term treatment guideline”) and “Guidelines on 
methodology for clinical assessment of antirheumatic drugs” (PFSB/ELD 
Notification No. 0217001, dated 17 February 2006), to collect data for 300 
subjects for 6 month period, and for 100 subjects for 1 year period in both 
ASP015K 100 mg and 150 mg groups among 015K-CL-RAJ2/RAJ3/RAJ4 
studies as long term treatment data, approximately 80 subjects per treatment 
group are necessary to be enrolled in Japan. In addition, the target sample size 
for Taiwan is set at 10 subjects per treatment group in consideration of the 
requirement of regulatory authority in Taiwan (10% or more Taiwan subjects) 
and target sample size for Korea is also set at 10 subjects per treatment group. 
Therefore, the target sample size per treatment group is set at 100 subjects in 
total for 3 regions. 
In addition to ASP015K and Placebo group, etanercept was set as open-label 
reference group and its target sample size is 200 subjects, considering the 
followings. 
o 
Incidence rates for serious infections from post marketing studies for 
approved biologic drugs [ACTEMRA®, drip infusion, 80 mg, 200 mg, 
400 mg, final reports for all patients ] [ORENCIA®, drip infusion, 
250 mg, information for appropriate drug usage] [HYUMIRA®, sc, 
40 mg, Syringe 0.8 mL, information for appropriate drug usage] 
[XELJANZ®, tablet, 5 mg, CTD (2013)] 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 29 of 134 
o 
Operational feasibility 
Statistical Methods: 
Setting the sample size of reference group as 200, it can be detectable at least 1 
subject with 95% confidence probability for AE which occurs at 1.5% 
incidence rate. 
 
[Primary Efficacy Variable Analysis] 
For the ACR20 response at Week 12/ET as primary efficacy variable, pairwise 
comparisons to placebo will be performed at each ASP015K dose level using 
logistic regression model with treatment group (Placebo, ASP015K 100 mg, 
and ASP015K 150 mg) as the factor and the prior biologic-DMARD-IR, 
concomitant DMARD use during the study period, and study region (Japan, 
Korea and Taiwan) as the covariates. For multiplicity adjustment, following 
closed testing procedure will be done. 
Step 1. ACR20 response at Week 12/ET: ASP015K 150 mg vs. Placebo 
Step 2. ACR20 response at Week 12/ET: ASP015K 100 mg vs. Placebo 
The null hypotheses will be tested at a significance level of 0.05. 
For the missing data imputation of ACR20 at Week 12/ET, Last Observation 
Carried Forward (LOCF) methodology will be used. 
 
[Secondary Efficacy Variable Analysis] 
For secondary efficacy endpoints, binary variables such as Percentage of 
subjects achieving ACR50 response at Week 12/ET, and Percentage of subjects 
achieving ACR70 response at Week 12/ET will be analyzed using logistic 
regression model as described in the primary analysis with treatment group as 
the factor, and the prior biologic-DMARD-IR, concomitant DMARD use 
during the study period and study region (Japan, Korea and Taiwan) as the 
covariates. Continuous variables, such as Change from baseline/Day 1 to Week 
12/ET in DAS28-CRP and DAS28-ESR scores, will be analyzed using analysis 
of covariance (ANCOVA) with treatment group as factor, and the prior 
biologic-DMARD-IR, concomitant DMARD use, study region (Japan, Korea 
and Taiwan) and baseline value as the covariates. Each ASP015K group will 
be compared with placebo group and multiplicity for the secondary efficacy 
variables will not be adjusted. 
[Safety and Other Variables Analyses] 
Summary statistics will be calculated for trough levels and biomarker 
concentrations by dose and time point. 
AEs will be coded using the Medical Dictionary for Regulatory Activities 
(MedDRA). The incidence of AEs, serious AEs (SAEs), AEs leading to 
discontinuation, and AEs related to study drug will be summarized. All AEs 
will be listed. Descriptive statistics for laboratory values, vital signs, body 
weight, 12-lead ECG results, QT variables (including QTc) and their changes 
from baseline over time will be provided. 
 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 30 of 134 
V. 
FLOW CHART AND SCHEDULE OF ASSESSMENTS 
Flow Chart 
 
 
Obtaining 
informed 
consent 
 
Screening period 
(The screening test 
period must be 
within 28 days 
prior to the baseline 
visit.) 
 
Confirmation of 
inclusion/exclusion 
criteria 
Preliminary 
registration 
 
Baseline 
 
Confirmation of 
inclusion/exclusion 
criteria 
Enrollment and 
randomization 
 
Treatment period: 
maximum of 52 
weeks, ranging 
from the start of 
the treatment with 
the study drug or 
reference drug to 
the completion of 
tests/assessments 
schedule at the end 
of treatment (Week 
52 or early 
termination) 
 
See figure below. 
 
Entry into the 
extension study 
Subjects in the 
reference group or 
who do not proceed 
to the extension 
study will undergo 
follow-up 
observation 4 
weeks after the end 
of the study 
treatment. 
→ 
→ 
→ 
→ 
 
 
 
→ 
 
 
 
 
Placebo
0W
ベースライン
12W
52W
完
了
例
は
非
盲
検
継
続
投
与
試
験
へ
移
行
Placebo群
ASP015K 100mg 群
ASP015K 150mg 群
ASP015K
100 mg/日
ASP015K
150 mg/日
盲検下で用量変更
スクリーニング期間
スクリーニング検査期
間（28日間）
Primary endpoint
ACR20%
DMARD-IR
判定
エタネルセプト
50mg/週（非盲検）
参照群
（エタネルセプト投
与）
ASP015K
100 mg/日
ASP015K
150 mg/日
割付（プラセボ群の12週の
変更用量も併せて決定）
スクリーニング
開始時
Initiation of 
screening 
Placebo group
Screening period 
Screening test period  
(28 days) 
ASP015K 100 mg
group
ASP015K 150 mg
group
Reference group 
(etanercept treatment) 
DMARD-IR 
evaluation 
Dose change under the blinded 
condition. 
Placebo 
ASP015K 100 mg/day 
ASP015K 150 mg/day 
ASP015K 100 mg/day 
ASP015K 150 mg/day 
Etanercept 50 mg/week (open-label) 
12 W 
52 W 
0 W 
Baseline 
Random allocation (including the 
doses to be assigned to subjects in 
the placebo group at Week 12) 
Primary efficacy variable: 
ACR20 
Subjects completing the study can enroll into the open-label extension study. 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 31 of 134 
Table 1: Schedule of Assessment 
Visit 
Initiation 
of 
Screening1) 
Screening 
Test 
Period 
0 
W 
4 
W 
8 
W 
12 
W 
16 
W 
20 
W 
24 
W 
28 
W 
32 
W 
36 
W 
40 
W 
44 
W 
48 
W 
52 
W 
Early 
Termination 
Follow-up2)  
Unscheduled 
Visit 
Visit day 
−1 at latest 
−28 to −1 
1 
29 
57 
85 
113 
141 
169 
197 
225 
253 
281 
309 
337 
365 
Within 2 
days of 
withdrawal 
28 days after 
Week 52 or 
early 
termination 
visit 
- 
Allowable range from 
specified date 
 
 
 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
+2 
±7 
- 
Informed consent 
○ 
Inclusion/exclusion 
criteria 
○ 
○ 
○ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Subject registration 
○ 
○ 
○ 
 
 
○ 
○ 
○ 
Confirmation of 
DMARD-IR 
○ 
 
○ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Demographics 
○ 
○ 
○ 
Medical history 
○ 
○ 
○ 
Height 
 
○ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Tuberculin test 
 
○ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Safety 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Physical examination 
 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
▲ 
Body weight 
 
○ 
 
 
 
○ 
 
 
 
○ 
 
 
○ 
 
 
○ 
○ 
○ 
▲ 
Vital signs 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
▲ 
Hepatitis examination 
○ 
▲ 
Hematology3) 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
▲ 
Biochemistry3) 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
▲ 
Urinalysis3) 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
▲ 
Fasting lipid profile test 
○ 
 
 
○ 
 
○ 
 
○ 
 
 
○ 
 
 
○ 
○ 
○ 
▲ 
Chest radiography 
○ 
○ 
○ 
▲ 
▲ 
12-lead ECG 
○ 
○ 
○ 
○ 
▲ 
Central ECG4) 
 
 
○ 
○6) 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Pregnancy test5) 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
▲ 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 32 of 134 
Visit 
Initiation 
of 
Screening1) 
Screening 
Test 
Period 
0 
W 
4 
W 
8 
W 
12 
W 
16 
W 
20 
W 
24 
W 
28 
W 
32 
W 
36 
W 
40 
W 
44 
W 
48 
W 
52 
W 
Early 
Termination 
Follow-up2)  
Unscheduled 
Visit 
Visit day 
−1 at latest 
−28 to −1 
1 
29 
57 
85 
113 
141 
169 
197 
225 
253 
281 
309 
337 
365 
Within 2 
days of 
withdrawal 
28 days after 
Week 52 or 
early 
termination 
visit 
- 
Allowable range from 
specified date 
 
 
 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
+2 
±7 
- 
Adverse events 
 
 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
▲ 
Efficacy 
CRP and ESR 
 
○ 
(CRP 
only) 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
▲ 
TJC/SJC (68/66 joints) 
 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
▲ 
PGA (VAS), SGA 
(VAS), and 
subject’s assessment of 
pain (VAS) 
 
 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
▲ 
SF-36 v2® 
○ 
○ 
○ 
○ 
 
 
 
○ 
 
 
 
 
 
○ 
○ 
○ 
▲ 
WPAI 
 
 
○ 
○ 
○ 
○ 
 
 
 
○ 
 
 
 
 
 
○ 
○ 
○ 
▲ 
HAQ-DI 
 
 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
▲ 
PK/PD 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
▲ 
Blood sampling for 
trough concentration4) 
 
 
○ 
○ 
○ 
○ 
 
 
 
○ 
 
 
 
 
 
○ 
○ 
 
 
Blood sampling for 
post-dose drug 
concentration4) 
 
 
 
○ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Blood sampling for PD 
(biomarkers) 
 
 
○ 
○ 
○ 
○ 
 
 
 
○ 
 
 
 
 
 
○ 
○ 
○ 
▲ 
Blood sampling for PD 
(lymphocyte subset) 
 
 
○ 
○ 
○ 
○ 
 
 
 
○ 
 
 
 
 
 
○ 
○ 
○ 
▲ 
Informed consent for 
PGx research (relevant 
sites only)4) 
 
 
○ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Blood sampling for 
PGx (relevant sites 
only)4) 
 
 
○ 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 33 of 134 
Visit 
Initiation 
of 
Screening1) 
Screening 
Test 
Period 
0 
W 
4 
W 
8 
W 
12 
W 
16 
W 
20 
W 
24 
W 
28 
W 
32 
W 
36 
W 
40 
W 
44 
W 
48 
W 
52 
W 
Early 
Termination 
Follow-up2)  
Unscheduled 
Visit 
Visit day 
−1 at latest 
−28 to −1 
1 
29 
57 
85 
113 
141 
169 
197 
225 
253 
281 
309 
337 
365 
Within 2 
days of 
withdrawal 
28 days after 
Week 52 or 
early 
termination 
visit 
- 
Allowable range from 
specified date 
 
 
 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
±7 
+2 
±7 
- 
Study drug/reference 
drug 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Confirmation of 
remaining unused drugs 
 
 
 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
 
 
Prescription 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
○ 
 
The symbol “○” designates mandatory items, whereas the symbol “▲” denotes the optional items to be investigated on the basis of the clinical judgment of the 
investigator/sub-investigator. 
For details, see the respective sections of the protocol. 
1) Subjects who have signed the informed consent will undergo evaluation of DMARD response at the screening visit. 
2) Follow-up will not be performed for subjects starting the extension study immediately after the Week 52 visit. 
3) For details of the test parameters, refer to Section 5.4.4. 
4) Subjects in the reference group will not undergo these procedures. 
5) For pregnancy tests, serum samples will be used at the screening visit, and urine samples will be used at and after the baseline visit. 
6) Central ECG should be performed on the same day as blood sampling for post-dose drug concentration at Week 4 or Week 8 before and after study drug 
administration. 
 
 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 34 of 134 
VI. 
ACCEPTABLE RANGE OF SCHEDULE OF ASSESSMENTS 
The paragraphs that follow describe the allowable time windows on scheduled test and 
observation dates. 
Reasonable efforts must be made to perform the tests and observations specified for early 
termination and follow-up, even if they cannot be conducted within the allowable time frame. 
 
[Acceptable Time Ranges for Efficacy Tests] 
TJC/SJC (68/66 joints) and CRP 
Screening 
From 1 to 28 days prior to the baseline visit. 
Baseline 
Before the initiation of treatment with the study 
drug or reference drug on the baseline visit day. 
Study visits from Week 4 to 
Week 48 
Within ± 7 days of the protocol-specified date 
AND before the initiation of treatment with the 
study drug or reference drug on the visit day. 
Week 52 
Within ± 7 days of the protocol-specified date. 
Early termination 
Within 2 days of withdrawal. 
Follow-up 
Within ± 7 days of the date 28 days after the Week 
52 OR early termination visit. 
PGA (VAS), SGA (VAS), Subject’s Assessment of Pain (VAS), HAQ-DI, and ESR 
Baseline 
Before the initiation of treatment with the study 
drug or reference drug on the baseline visit day. 
Study visits from Week 4 to 
Week 48 
Within ± 7 days of the protocol-specified date 
AND before the initiation of treatment with the 
study drug or reference drug on the visit day. 
Week 52 
Within ± 7 days of the protocol-specified date. 
Early termination 
Within 2 days of withdrawal. 
Follow-up 
Within ± 7 days of the date 28 days after the Week 
52 OR early termination visit. 
 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 35 of 134 
SF-36 v2®, WPAI 
Baseline 
Before the initiation of treatment with the study 
drug or reference drug on the baseline visit day. 
Weeks 4, 8, 12, and 28 
Within ± 7 days of the protocol-specified date 
AND before the initiation of treatment with the 
study drug or reference drug on the visit day. 
Week 52 
Within ± 7 days of the protocol-specified date. 
Early termination 
Within 2 days of withdrawal. 
Follow-up 
Within ± 7 days of the date 28 days after the Week 
52 OR early termination visit. 
 
[Acceptable Time Ranges for Safety Tests] 
Physical Examination, Vital Signs, Laboratory Tests [Hematology, Serum Biochemistry, 
Urinalysis, Pregnancy Test (serum/urine)] 
Screening 
From 1 to 28 days prior to the baseline visit. 
Baseline 
Before the initiation of treatment with the study 
drug or reference drug on the baseline visit day. 
Study visits from Week 4 to 
Week 48 
Within ± 7 days of the protocol-specified date 
AND before the initiation of treatment with the 
study drug or reference drug on the visit day. 
Week 52 
Within ± 7 days of the protocol-specified date. 
Early termination 
Within 2 days of withdrawal. 
Follow-up 
Within ± 7 days of the date 28 days after the Week 
52 OR early termination visit. 
Body Weight 
Screening 
From 1 to 28 days prior to the baseline visit. 
Weeks 12, 28, and 40 
Within ± 7 days of the protocol-specified date 
AND before the initiation of treatment with the 
study drug or reference drug on the visit day. 
Week 52 
Within ± 7 days of the protocol-specified date. 
Early termination 
Within 2 days of withdrawal. 
Follow-up 
Within ± 7 days of the date 28 days after the Week 
52 OR early termination visit. 
 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 36 of 134 
Fasting Lipid Profile Test 
Baseline 
Before the initiation of treatment with the study 
drug or reference drug on the baseline visit day 
AND 8 or more hours after the last meal. 
Weeks 12, 20, 28, and 40 
Within ± 7 days of the protocol-specified date  
Before the initiation of treatment with the study 
drug or reference drug on the study visit day AND 
8 or more hours after the last meal. 
Week 52 
Within ± 7 days of the protocol-specified date 
AND 8 or more hours after the last meal. 
Early termination 
Within 2 days after withdrawal AND 8 or more 
hours after the last meal (the nutritional condition 
is recommended but not compulsory). 
Follow-up 
Within ± 7 days of the date 28 days after the Week 
52 OR early termination visit. 
Chest Radiography 
Screening 
From 1 to 28 days prior to the baseline visit. 
Radiographs taken before the informed consent 
will be acceptable as long as they were taken 
within 90 days before the baseline visit. 
Weeks 28 and 52 
Within ± 7 days of the protocol-specified date. 
Early termination 
Within 2 days of withdrawal. 
Not mandatory; may be required at the discretion 
of the investigator/sub-investigator. 
12-lead ECG 
Screening 
From 1 to 28 days prior to the baseline visit. 
Week 28 
Within ± 7 days of the protocol-specified date 
AND before the initiation of treatment with the 
study drug or reference drug on the visit day. 
Week 52 
Within ± 7 days of the protocol-specified date. 
Early termination 
Within 2 days of withdrawal. 
 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 37 of 134 
Central ECG (except for the reference group) 
Baseline 
Before the initiation of treatment with the study 
drug on the baseline visit day 
Week 4 or 8 
(before study drug 
administration) 
Within ± 7 days of the protocol-specified date 
AND before the initiation of treatment with the 
study drug on the visit day. 
Week 4 or 8 
(after study drug 
administration) 
Within ± 7 days of the protocol-specified date 
AND 2-hour post-dose on the visit day 
(Recommended time point. Sampling from 1 hour 
to 4 hours post-dose will be acceptable.) 
 
[Acceptable Time Ranges for PD Tests: Biomarker and Lymphocyte Subset 
Measurements] 
Baseline 
Before the initiation of treatment with the study 
drug or reference drug on the baseline visit day. 
Weeks 4, 8, 12, and 28 
Within ± 7 days of the protocol-specified date 
AND before the initiation of treatment with the 
study drug or reference drug on the visit day. 
Week 52 
Within ± 7 days of the protocol-specified date. 
Early termination 
Within 2 days of withdrawal. 
Follow-up 
Within ± 7 days of the date 28 days after the Week 
52 OR early termination visit. 
 
[Acceptable Time Ranges for Blood Sampling for Plasma Drug Concentration] 
Trough Concentration (except the reference group) 
Baseline 
Before the initiation of treatment with the study 
drug on the baseline visit day. 
Weeks 4, 8, 12, 28, and 52 
Within ± 7 days of the protocol-specified date 
AND within 19 to 29 hours between the time of 
treatment with the study drug before blood 
collection and the time of blood collection. 
Early termination 
Within 2 days after withdrawal. 
Post-Dose Drug Concentration (except the reference group) 
Week 4 or 8 
The recommended time point is 2 hours post-dose. 
Sampling from 1 hour to 4 hours post-dose will be 
acceptable. 
 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 38 of 134 
1 
INTRODUCTION 
1.1 
Background 
Rheumatoid arthritis (RA) is a chronic systemic inflammatory autoimmune disease that 
targets the synovial tissues [O’Dell, 2004]. The synovial inflammation is associated with 
irreversible cartilage destruction and erosion of bone, which may cause pain as well as 
decreased activity of daily living (ADL) due to functional impairment, and therefore reduce 
quality of life (QOL). The goal of RA treatment is to control the disease activity and achieve 
remission by preventing or controlling joint destruction, preventing loss of function, and 
relieving pain, thereby improving patient QOL. 
Conventional RA treatments have been based on pain control with nonsteroidal 
anti-inflammatory drugs and inflammation control with corticosteroids, with which 
disease-modifying antirheumatic drugs (DMARDs) have been combined [Nakajima, 2009]. 
After the approval of methotrexate (MTX) and biologics, RA treatment improved greatly, 
shifting its goal from pain control to induction and maintenance of remission. In more recent 
years, the ultimate goal of RA therapy evolved to include clinical, structural, and functional 
remission. Now, researchers are attempting to achieve drug-free remission. 
In Japan, MTX has been established as the standard first-line therapy for RA. The 
combination of tumor necrosis factor (TNF) inhibitors and other biological agents with MTX 
has paved the way for the treat-to-target (T2T) approach aimed at clinical and structural 
remission. 
However, it has been that such combination therapies induced clinical remission in 
approximately 30% to 50% of treated patients [Y. Tanaka, 2009; K. Yamaoka, 2008], failing 
to control disease in most cases. In addition, MTX, a non-specific inhibitor of cellular 
proliferation, frequently causes adverse drug reactions in proliferative tissues such as the 
gastrointestinal epithelium and bone marrow, and these reactions lead to premature 
discontinuation in a certain proportion of patients. TNF inhibitors (e.g., etanercept, 
infliximab, adalimumab), selective T-cell co-stimulation modulators (e.g., abatacept), and 
other biologics are very expensive and require intravenous or subcutaneous administration; 
the issues of cost, cumbersome dosing procedure, and other factors are a hindrance to their 
application. Under these circumstances, low-molecular-weight DMARDs acting on a novel 
molecular target have captured increasing interest from drug companies. 
 
ASP015K is an oral Janus kinase (JAK) inhibitor discovered by Astellas Pharma. In vitro 
kinase assays demonstrated that this agent effectively inhibited JAK1, JAK2, JAK3, and 
tyrosine kinase 2 (TYK2). In particular, JAK3 was suppressed in a relatively selective 
manner. The binding of the ligand to the cytokine receptor triggers JAK activation, and 
activated JAK molecules in turn phosphorylate the receptor. The phosphorylation of the 
cytokine receptor creates a site for interaction with the signal transducer and activator of 
transcription (STAT). Upon JAK-induced phosphorylation, STAT forms a dimer complex 
and enters into the nucleus, where the STAT dimer binds with DNA to regulate gene 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 39 of 134 
transcription. Because JAK3 expression is restricted to primarily hematopoietic cells, JAK3 
inhibition is a desirable therapeutic target for immunosuppression in human organ 
transplantation and immunomodulation in autoimmune disorders [Papageorgiou and Wikman, 
2004], without significantly affecting other organ systems [Kremer et al, 2009]. 
Xeljanz® (tofacitinib) 5 mg is a JAK inhibitor approved by the US FDA in 2012 for the 
treatment of adult patients with moderate to severe RA who had an inadequate response to or 
are intolerant of MTX. In Japan, this drug was approved in March 2013 for treating RA 
patients who had an inadequate response to conventional therapies. 
Astellas Pharma is pursuing the development program of ASP015K for the indication of RA. 
In Japan, the Phase IIb dose-finding study (015K-CL-RAJ1) has been completed, and its 
long-term extension study (015K-CL-RAJ2, or RAJ2) is ongoing. Overseas, 2 Phase II 
dose-finding studies (1 with MTX and the other without MTX) have been completed, and 
their follow-up extension study is underway, similar to the situation in Japan. The results of 
015K-CL-RAJ1 showed that ASP015K caused a significantly higher improvement in RA 
than placebo in terms of the ACR response rate, DAS28 score, and other efficacy variables, 
suggesting its usefulness for treating RA. 
 
1.2 
Non-clinical and Clinical Data 
1.2.1 
Nonclinical Pharmacology and Safety Pharmacology 
ASP015K is a novel oral immunosuppressant that exerts it pharmacological action by 
relatively selectively inhibiting JAK3, a key enzyme in the IL-2 signaling pathway. In vitro 
kinase studies showed that ASP015K also inhibited JAK1, JAK2, and TYK2, although less 
potently than it inhibited JAK3. In a study using a rat model of adjuvant-induced arthritis, 
prophylactic use of ASP015K significantly suppressed the swelling of the injected limb and 
prevented the worsening of the bone destruction score assessed by radiography. Therapeutic 
administration of ASP015K in which treatment was initiated after the occurrence of pedal 
edema also prevented the event and reduced joint destruction scores. 
In safety pharmacology studies, ASP015K showed no effect on human ether-a-go-go related 
gene (hERG) current or action potential duration in isolated guinea pig papillary muscles at 
clinically relevant concentrations. ASP015K had no effect on the central nervous system 
(modified Irwin's method) of rats at up to 100 mg/kg orally. In monkeys, loose/watery stools 
and a tendency towards reduced blood potassium concentrations were observed at 60 mg/kg 
orally, but there were no effects on the central nervous system, cardiovascular system 
[electrocardiogram (ECG), blood pressure, or heart rate], or respiratory system of monkeys at 
up to 60 mg/kg. 
1.2.2 
Pharmacokinetics and Pharmacodynamics 
1.2.2.1 Nonclinical Pharmacokinetics 
Absolute bioavailability ranged from 39.8% to 46.4% in rats and 18.9% to 19.2% in monkeys. 
Following a single oral dose of 3 mg/kg 14C-ASP015K in Sprague-Dawley rats, radioactivity 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 40 of 134 
distributed rapidly into tissues with no long-term tissue retention observed. In a study with 
pigmented rats, the dosed radioactivity was rapidly excreted within the first 24 hours after 
administration in almost all tissues with the exception of the eyeball (t1/2 of 1105.8 hours). No 
apparent differences were noted in radioactivity concentration-time profiles between 
nonpigmented and pigmented skin, and the radioactivity was not detected in these skins for a 
long time. These data suggest that ASP015K-related compounds may have bound to melanin, 
but binding was likely weak and reversible. In Sprague-Dawley rats orally administered 
14C-ASP015K 3 mg/kg once daily for 21 days, radioactivity was slowly eliminated from the 
lung, spleen, skin, bone marrow, testis, and thoracic aorta. With the exception of the thoracic 
aorta, the radioactivity levels 168 hours after the last dose were reduced to 19% or less of the 
levels measured 0.25 hours after the last dose. The mean radioactivity of the thoracic aorta at 
168 hours of the last dose was as low as less than 3 times the lower limit of quantification. 
The in vitro plasma protein binding rates of ASP015K and its metabolite AS2628528 (H2) 
were determined in the concentration range of 0.2–20 μg/mL. The plasma protein binding 
rates in mice, rats, rabbits, dogs, monkeys, and humans were in the ranges of 59%–95% for 
ASP015K and 84%–99% for H2. Among human plasma proteins, human serum albumin 
(HSA) most preferentially bound to ASP015K and H2. 
In pregnant and lactating rats administered a single oral dose of 14C-ASP015K 3 mg/kg, the 
radioactivity was distributed widely across different tissues of the dams, although the tissue 
radioactivity almost completely disappeared within 24 hours. Although the levels of placental 
radioactivity transfer were low, comparatively higher levels of radioactivity were rapidly 
transferred to the milk, leading to elevated radioactivity in pups via lactation.  
When 14C-ASP015K was orally administered alone to rats at a dose of 3 mg/kg, 3 
radioactivity peaks were detected in plasma on the radiochromatogram, with the main peak 
being that of the unchanged drug. In vitro metabolic profile of 14C-ASP015K was performed 
in liver microsomes and cryopreserved hepatocytes from mice, rats, rabbits, dogs, 
cynomolgus monkeys, and humans. No human-specific metabolites were identified in either 
assay. In in vitro metabolic studies, ASP015K was metabolized to H2 by human 
sulfotransferase 2A1 (hSULT2A1) and to AS2604202 (H4) by human nicotinamide 
N-methyltransferase (hNNMT). 
In rats orally administered a single 14C-ASP015K dose, 25.2% and 46.7% of the administered 
radioactivity was eliminated into urine and bile at 72 hours, respectively, suggesting an 
excellent oral absorption profile of ASP015K. In monkeys orally administered a single 
14C-ASP015K dose, 22.3% and 26.4% of the administered radioactivity was eliminated into 
urine and bile at 72 hours, respectively. 
1.2.2.2 Clinical Pharmacokinetics and Pharmacodynamics 
A total of 17 clinical studies of ASP015K have been completed till date. These studies 
included 14 pharmacokinetic studies in healthy adult volunteers, 1 pharmacokinetic study in 
RA patients, 1 efficacy and safety study in patients with psoriasis, and 1 efficacy and safety 
study in RA patients. More specifically, they were as follows: a single-dose and 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 41 of 134 
repeated-dose study in Japanese and Caucasian subjects conducted in Japan 
(015K-CL-HV03), an overseas single ascending dose and food effect study 
(015K-CL-HV01), an overseas repeated-dose study (015K-CL-HV02), a mass balance study 
using radiolabeled ASP015K (015K-CL-PK03), a regional absorption study 
(015K-CL-PK15), 4 relative bioavailability and food effect studies (015K-CL-PK09, 
015K-CL-PK18, 015K-CL-PK19, 015K-CL-PK51), 5 drug–drug interaction (DDI) studies in 
healthy adult volunteers (015K-CL-PK01, 015K-CL-PK02, 015K-CL-PK05, 015K-CL-PK16, 
and 015K-CL-PK26), 1 DDI study in RA patients (015K-CL-PK13), 1 efficacy and safety 
study in psoriasis patients (015K-CL-PS01), and 1 efficacy and safety study in RA patients 
(015K-CL-RAJ1). 
These completed studies involved 472 healthy adults and 296 RA patients; they received 
ASP015K doses ranging from 3 to 300 mg/day in single-dose studies and from 10 to 200 mg 
twice daily (BID) in repeated-dose studies. In addition, 124 patients with psoriasis were 
enrolled and were administered 10 to 100 mg BID or 50 mg once daily (QD). 
After a single dose of 3 to 300 mg/day administered under fasting conditions in Study 
015K-CL-HV01, ASP015K was rapidly absorbed with a median tmax ranging from 1.0 to 1.75 
hours across the dose groups. The AUCinf, AUClast, and Cmax of ASP015K increased dose 
proportionally. Elimination occurred in a multiphasic manner with a mean t1/2 value of 2.8 to 
18.5 hours. Compared to administration under fasting conditions, the mean Cmax of ASP015K 
administered under fed conditions increased by 5%. Similarly, the mean AUCinf increased by 
27% with tmax being prolonged for approximately 2.5 hours. Urinary excretion of ASP015K 
accounted for between 9% and 15% of the oral dose. ASP015K inhibited JAK3-mediated 
phosphorylation of STAT5 dose-dependently. Peak inhibition of JAK3-mediated 
phosphorylation of STAT5 was observed around 1 to 2 hours (median) following 
administration of ASP015K under fasting conditions. At a dose of 60 mg, the peak inhibition 
reached 84% of the maximum. The mean changes from baseline lymphocyte counts and 
peripheral lymphocyte subsets suggested there were no time- or dose-dependent changes 
after a single oral dose of ASP015K. 
Study 015K-CL-HV02, in which ASP015K was given at doses of 30 mg BID, 100 mg BID, 
or 200 mg BID for 14 days under non-fasting conditions, demonstrated no clear difference in 
pharmacokinetics of ASP015K after repeated dosing between the morning and evening doses, 
although the trough level after the morning dose tended to be lower. Steady state in plasma 
ASP015K concentrations was achieved by Day 3. The mean accumulation factor on Day 14 
was between 1.12 and 1.65 for Cmax, 1.38 and 1.65 for AUC12, and 2.02 and 2.71 for Ctrough, 
PM. At steady state, the peak-trough ratios (peak/trough levels) of ASP015K concentrations 
were between 8.8 and 18. Overall, Cmax and AUC12 values generally increased dose 
proportionally over the range of 30 to 100 mg BID. There was no sex difference in ASP015K 
exposure with the 100 mg BID dose. 
As a result of metabolite analysis of samples collected in 015K-CL-HV01 and 
015K-CL-HV02, 3 metabolites (H1, H2, H4) were identified from plasma samples and 6 
metabolites (H1 to H6) were identified from urine samples. 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
Astellas 
Page 42 of 134 
Results from the mass balance study (015K-CL-PK03) indicated that unchanged ASP015K 
accounted for 36% of the total radioactivity in plasma (metabolites accounted for the 
remaining 64%). Approximately 36.8% of the total radioactivity was excreted in urine and 
56.6% in feces. Unchanged ASP015K accounted for 36% of the total radioactivity in urine. 
In Study 015K-CL-HV03, Japanese had greater ASP015K exposure than Caucasian. After 
adjustment for dose and body weight, Cmax was 42.9% to 53.9% higher and AUCinf was 
22.5% to 44.9% higher in Japanese relative to Caucasian. JAK3 inhibition was 
dose-dependent in Japanese and Caucasian. Consistent with the generally higher plasma 
concentrations of ASP015K in Japanese, the peak inhibition of JAK3 following a single dose 
of ASP015K was also higher in Japanese. Overall, the mean change from baseline for T cell 
subsets was similar with ASP015K single or repeated dosing, with little variation among 
ethnicity. 
Results from a regional absorption study (015K-CL-PK15) indicated that absorption 
primarily (≥ 50%) occurred in the proximal small bowel, and the rate and extent of 
absorption decreased as the delivery site became more distal within the gastrointestinal tract. 
In Study 015K-CL-PK19, subjects were administered ASP015K (5 tablets of 30 mg) after a 
meal (approximately 500 to 600 kcal, with fat accounting for 25% to 35% of the total 
calories). Compared with fasting conditions, tmax was extended by 0.5 hours, and Cmax and 
AUC increased by 34% and 27%, respectively. 
In the 6 DDI studies, the pharmacokinetic profile of ASP015K was investigated in the 
presence of: mycophenolate mofetil (MMF) (015K-CL-PK01), tacrolimus (015K-CL-PK02 
and 015K-CL-PK16), midazolam (015K-CL-PK05), MTX (015K-CL-PK13), and 
rosuvastatin (015K-CL-PK26). MMF, tacrolimus, midazolam, and rosuvastatin were 
administered in healthy adult volunteers, whereas MTX was used in RA patients. 
Administration of ASP015K 100 mg BID had no effect on the pharmacokinetic profile of 
MTX in patients with RA or the MMF metabolites MPA and MPAG in healthy volunteers. 
ASP015K 60 mg and 100 mg BID did increase tacrolimus levels in whole blood following 
oral administration of tacrolimus 5 mg, but not when tacrolimus was administered as a 1 mg 
intravenous dose. Concomitant use of ASP015K elevated the plasma midazolam 
concentrations after a single oral dose of midazolam 3 mg. It also raised the plasma 
rosuvastatin levels following a single oral dose of rosuvastatin 10 mg. However, steady-state 
pharmacokinetics of ASP015K were not significantly impacted by MTX 15 to 25 mg, MMF 
1 g, midazolam 3 mg, oral tacrolimus 5 mg, or intravenous tacrolimus 1 mg doses. 
In Study 015K-CL-PS01 that enrolled patients with psoriasis, the administration of ASP015K 
10 to 100 mg BID elevated ASP015K exposure (Cmax, AUClast, and AUC6h) in a 
dose-dependent manner. The median tmax values were in the range of approximately 1.0 to 
1.8 hours. STAT5 phosphorylation and JAK3 activity were inhibited in a dose-dependent 
manner. Although no consistent trends were noted for the absolute lymphocyte count, a slight 
dose-dependent decreasing trend was noted for the proportions and absolute counts of NK 
and B cells. 

Sponsor: Astellas Pharma Inc. 
ISN/Protocol <015K-CL-RAJ3> 
 
- CONFIDENTIAL - 
3 March 2017 
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In Study 015K-CL-RAJ1 of Japanese patients with RA, matrix metalloproteinase 3 (MMP-3) 
levels decreased in a dose-dependent manner following the administration of ASP015K 25 to 
150 mg QD. Although no consistent trends were noted for the absolute lymphocyte count, 
NK cell counts decreased and B cell counts increased in a dose-dependent manner. 
1.2.3 
Toxicology 
Nonclinical repeated-dose toxicity studies of ASP015K were conducted using rats (up to 26 
weeks) and monkeys (up to 52 weeks). Toxicities observed in these studies were mainly 
related to gastrointestinal, hematopoietic, muscular, and immune systems. All these findings 
were reversible and resolved upon the withdrawal of ASP015K. Muscle toxicity was 
observed in monkeys: mild multifocal muscle necrosis in 1 female at 60 mg/kg/day in the 
4-week preliminary study; elevation of CPK and LDH without histopathological changes in 2 
males at 60 mg/kg/day in the 4-week preliminary study; elevation of CPK and LDH without 
histopathological changes in 1 male that was sacrificed in extremis in 13-week study, and a 
transient increase of CPK without histopathological changes observed in another male in the 
same 13-week study. 
Genotoxicity studies were conducted in vitro and in vivo. ASP015K was negative in the 
reverse mutation test in bacteria but was positive in an in vitro chromosomal aberration test 
in Chinese hamster lung cells. ASP015K was negative in 2 in vivo genotoxicity studies, the 
unscheduled DNA synthesis test in rats and the micronucleus test in mice. These results 
suggested that ASP015K had little potential to induce chromosomal aberrations in in vivo. 
In toxicity studies on the fertility and early embryonic development in rats, the viability of 
embryos decreased after implantation and the number of live embryos decreased in the 
100 mg/kg/day group compared with the control group. ASP015K neither induced general 
toxicity nor impacted male or female fertility up to the dose of 100 mg/kg/day. In an 
embryo–fetal development study in rats, increased incidences of skeletal abnormalities and 
variations and visceral variations were noted at 30 mg/kg/day and higher, while increased 
incidences of visceral and external abnormalities were observed at 300 mg/kg/day. NOAEL 
for embryo–fetal development in rats was 10 mg/kg/day. In an embryo–fetal developmental 
toxicity study in rabbits, no teratogenicity was observed; however, increased 
postimplantation loss and decreased numbers of live fetuses were noted at 10 mg/kg/day. 
Four- and 13-week toxicity studies of ASP015K administered in combination with tacrolimus, 
MMF, or MTX demonstrated no significant synergistic toxicities.  
1.2.4 
Efficacy 
In a double-blind, placebo-controlled study conducted in Japan (015K-CL-RAJ1), the dose 
response for the efficacy and safety of once-daily oral ASP015K (25, 50, 100, 150 mg) was 
investigated in 281 patients with moderate to severe RA. Its primary efficacy variable was 
the ACR20 response rate at Week 12. The ACR20 response rates were 10.7% for placebo, 
23.6% for 25 mg, 31.6% for 50 mg, 54.5% for 100 mg, and 65.5% for 150 mg groups. 
Significant improvements over placebo were noted for 50 mg (P=0.021), 100 mg (P<0.001), 
and 150 mg groups (P<0.001). In addition, logistic regression analysis demonstrated a 

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statistically significant dose–response relationship (P<0.001). Secondary efficacy variables, 
the ACR50 response rate, ACR70 response rate, and DAS28-CRP, exhibited significant 
improvements for ASP015K over placebo. A long-term extension study (015K-CL-RAJ2) for 
patients who completed this study is underway to investigate the efficacy and safety of 
ASP015K administered over an extended period of time. 
Overseas, 3 clinical studies of patients with moderate to severe RA have been completed 
(015K-CL-RA21, 015K-CL-RA22, 015K-CL-RA25). 015K-CL-RA21 and 015K-CL-RA22 
were dose-finding studies of ASP015K administered with and without MTX, respectively. 
015K-CL-RA25 was a long-term follow-up extension study that enrolled the patients who 
completed either of the 2 studies. 
In a US double-blind, placebo-controlled study in patients with moderate to severe psoriasis 
vulgaris (015K-CL-PS01), 124 subjects were orally administered ASP015K (10, 25, 60, 
100 mg BID or 50 mg QD) over 6 weeks. Compared with placebo, all ASP015K groups 
showed greater improvements in terms of change from baseline in the PASI score (primary 
efficacy variable), depicting a statistically significant difference in the overall therapeutic 
response. For secondary efficacy variables, the treatment success based on Physician’s Static 
Global Assessment (PSGA) and 75% reduction in the PASI score (PASI 75 response) 
demonstrated the efficacy of ASP015K. 
 
1.3 
Summary of Key Safety Information for Study Drugs 
The safety and tolerability of ASP015K were evaluated in 14 studies in healthy adult 
volunteers (13 overseas and 1 Japanese), 2 studies in RA patients (1 each overseas and 
Japanese), and 1 study in patients with psoriasis (overseas). In these studies, a single dose of 
3 to 300 mg and repeated doses of 10 to 200 mg BID were administered in 423 healthy adults 
and 14 RA patients. In addition, 225 RA patients received repeated doses of 25 to 150 mg 
QD, and 95 psoriasis patients received repeated doses of 10 to 200 mg BID or 50 mg QD. 
Treatment emergent adverse events (TEAEs) that occurred relatively frequently in these 
studies included gastrointestinal disorders (e.g., diarrhoea, nausea, flatulence, vomiting) and 
nervous system disorders (e.g., headache). 
In the overseas single-dose study (015K-CL-HV01), there was no evidence of clinically 
significant safety findings in subjects who received single oral doses of ASP015K (3, 10, 30, 
60, 120, 200 and 300 mg) under fasted conditions or a single 120 mg oral dose in the fed 
state. The more common TEAEs in this study that occurred in multiple subjects were 
headache (7 subjects; moderate in 1 subject and mild in 6 subjects); mild, tension headache 
(3 subjects); flatulence (3 subjects; moderate in 1 subject and mild in 2 subjects); and mild, 
asymptomatic bradycardia (2 subjects). 
In the overseas repeat-dose study (015K-CL-HV02), the more common TEAEs in the 36 
subjects receiving ASP015K were neutropenia (14 subjects; severe in 1 subject, moderate in 
3 subjects, and mild in 10 subjects); headache (7 subjects; moderate in 2 subjects and mild in 
5 subjects); mild, abdominal pain (6 subjects); mild, diarrhoea (4 subjects); and nausea (4 

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subjects; moderate in 1 subject and mild in 3 subjects). Dose-dependent gastrointestinal 
disorders (e.g., nausea, diarrhoea, dyspepsia, and abdominal pain) and neutropenia were 
observed, especially in approximately two-thirds of subjects (6 of 9 subjects) in the highest 
dose group (ASP015K 200 mg BID). In this repeat-dose study, 2 subjects experienced severe 
TEAEs and 8 experienced moderate TEAEs. Severe TEAEs included elevated lipase and 
CPK elevation that occurred in 1 male subject (200 mg BID group) and neutropenia in 1 
female subject (100 mg BID group). 
In the single-dose and repeated-dose study in Japanese and Caucasian volunteers 
(015K-CL-HV03), the only TEAE observed in at least 1 subject after a single dose of 
ASP015K was mild white blood cell count increased in 2 of 6 Japanese subjects receiving 
ASP015K 60 mg and 1 of 6 Japanese subjects receiving ASP015K 200 mg. TEAEs observed 
in at least 1 subject who received repeated doses of ASP015K were mild neutrophil count 
decreased in 3 of 6 Japanese male subjects receiving ASP015K 100 mg BID; mild white 
blood cell count increased in 2 of 6 Japanese male subjects receiving ASP015K 30 mg BID 
and 1 of 6 Japanese male subjects receiving ASP015K 10 mg BID; and mild alanine 
aminotransferase increased in 1 of 6 Japanese male subjects receiving ASP015K 10 mg BID 
and in 1 of 6 Japanese male subjects receiving ASP015K 100 mg BID. 
There were no vital sign or ECG findings observed in subjects following administration of 
ASP015K in the previous clinical pharmacology studies that were considered clinically 
relevant, except mild, asymptomatic bradycardia (possibly related; recovered) in 2 subjects in 
the overseas single-dose study (015K-CL-HV01), and intermittent, mild arrhythmia (not 
related; recovered) lasting for approximately 5 hours in 1 subject after a single dose of 
ASP015K 100 mg in the DDI study of ASP015K with midazolam (015K-CL-PK05). 
DDI studies involving MTX, MMF, midazolam, tacrolimus, and rosuvastatin 
(015K-CL-PK01, 015K-CL-PK02, 015K-CL-PK05, 015K-CL-PK13, 015K-CL-PK16, 
015K-CL-PK26) demonstrated that ASP015K administered in combination with these agents 
was well tolerated, and reported TEAE incidence rates comparable with those documented 
for ASP015K as single-agent therapy. 
In the Japanese clinical trial in RA patients (015K-CL-RAJ1), the incidence rates of AEs in 
the ASP015K 25 mg, 50 mg, 100 mg, and 150 mg groups were 70.9%, 64.9%, 52.7%, and 
67.2%, respectively. These rates were comparable with that of the placebo group (64.3%). 
The incidence rates of AEs whose relationship to the study drug could not be ruled out for the 
ASP015K 25 mg, 50 mg, 100 mg, and 150 mg groups were 38.2%, 43.9%, 29.1%, and 
55.2%, respectively. These rates were higher than that reported for the placebo group 
(28.6%). By severity (NCI-CTCAE), most were either Grade 1 or Grade 2. In the placebo 
and ASP015K 25 mg, 50 mg, 100 mg, and 150 mg groups, the numbers of subjects with 
serious adverse events (SAEs) were 1 (1.8%), 1 (1.8%), 2 (3.5%), 3 (5.5%), and 0, 
respectively. Death was reported from 1 subject of the 50 mg group (cerebral haemorrhage). 
AEs resulted in treatment discontinuation in 10 (17.9%), 7 (12.7%), 5 (8.8%), 6 (10.9%), and 
4 (6.9%) subjects of the placebo, ASP015K 25 mg, 50 mg, 100 mg, and 150 mg groups, 
respectively. The most common reason was rheumatoid arthritis aggravated (21/32). 

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Rheumatoid arthritis, nasopharyngitis, blood creatine phosphokinase (CPK) increased, 
diarrhoea, cystitis, constipation, stomatitis, dyspepsia, lipids increased, and blood 
triglycerides increased were reported at ≥ 5% incidence rates from 1 or more groups. By the 
MedDRA System Organ Class (SOC), Infections and infestations, Gastrointestinal disorders, 
Musculoskeletal and connective tissue disorders, and Investigations showed high incidence 
rates. Blood creatine phosphokinase increased were observed in 0, 2 (3.6%), 1 (1.8%), 1 
(1.8%), and 7 (12.1%) subjects of the placebo, ASP015K 25 mg, 50 mg, 100 mg, and 150 mg 
groups, respectively. Most cases were transient, and all subjects except 1 who prematurely 
discontinued the study recovered or were recovering. With regard to clinical laboratory 
testing, compared with the placebo group, the ASP015K groups showed decreased levels of 
neutrophils, platelets, and estimated glomerular filtration rate (eGFR) and elevated levels of 
CPK, hemoglobin, lymphocytes, creatinine, total cholesterol, LDL, HDL, and triglycerides. 
No noteworthy changes were detected in vital signs or ECG recordings. 
In the overseas study in psoriasis patients (015K-CL-PS01), none of the AEs observed were 
apparently dose-dependent, although the overall incidence of AEs in patients receiving 
ASP015K was higher than in those receiving placebo. No SAEs were reported. However, 1 
subject treated with 60 mg BID prematurely discontinued the study owing to mild neutrophil 
count decreased, and this case was judged possibly related to the study drug. The more 
common AEs were pharyngitis, diarrhoea, and flatulence, which did not occur more 
frequently in a specific treatment group including the placebo group. Mild neutrophil count 
decreased was observed in patients receiving ASP015K, with none having neutrophil count 
of less than 1000/mm3. The mean CPK level increased with dose. A total of 4 AEs of 
increased CPK were reported, each in the placebo, 10 mg BID, 25 mg BID, and 100 mg BID 
groups, none of which were associated with symptoms suggestive of myopathy. During this 
study, no anaemia occurred. While mild to moderate increases in HDL, triglycerides, and 
total cholesterol were observed, there was no change from baseline in LDL. 
For more information regarding the efficacy and safety of ASP015K, refer to the current 
version of the Investigator’s Brochure. 
For more information regarding the efficacy and safety of etanercept, refer to the current 
version of the package insert. 
 
1.4 
Risk-Benefit Assessment 
Findings from nonclinical studies of ASP015K suggest that the primary areas of toxicity are 
the gastrointestinal system, hematopoietic system, and muscle tissue. The commonly 
observed AEs during clinical studies conducted to date included reversible neutrophil count 
decreased, gastrointestinal disorders (e.g., diarrhoea, nausea, flatulence, vomiting), CPK 
elevations without evidence of myopathy, and headache. In the clinical trial of ASP015K in 
Japanese patients with RA (015K-CL-RAJ1), 1 or more groups reported rheumatoid arthritis, 
nasopharyngitis, blood creatine phosphokinase increased, diarrhoea, cystitis, constipation, 
stomatitis, dyspepsia, lipids increased, and blood triglycerides increased at incidence rates of 

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≥ 5%. By the MedDRA System Organ Class (SOC), Infections and infestations, 
Gastrointestinal disorders, Musculoskeletal and connective tissue disorders, and 
Investigations showed high incidence rates. Thus, these events may occur in the present 
study. 
In the 015K-CL-QT01 study to evaluate the effect of ASP015K on cardiac function (QT 
interval), single doses of ASP015K 150 mg and 450 mg shortened the QTcF interval (QT 
interval corrected using Fridericia’s Correction). The maximum decrease in the mean change 
from placebo- and baseline-adjusted QTcF occurred at 2 and 4 hour post dose with values of 
-12.0 and -14.7 msec for the 150 mg and 450 mg treatments, respectively. Therefore, 
shortened QT interval may be observed in the present study. The risk of drug-induced QT 
shortening is uncertain. 
Because ASP015K is an immunosuppressive agent, it may increase the risk of infections and 
reactivation of latent, chronic infections. In particular, excessive immunosuppression can 
lead to serious infections. Of note is the fact that Xeljanz® (tofacitinib) 5 mg, a member of 
the class of JAK inhibitors to which ASP015K belongs, has been associated with new onset 
or aggravation of serious infections such as tuberculosis, pneumonitis, sepsis, viral infections, 
and opportunistic infectious diseases including fungal infections. In addition, several cases of 
malignant tumors have been reported, although their causal relation to the agent has not been 
established. Based on the data pooled from 5 domestic and overseas comparative studies of 
Xeljanz® (tofacitinib) 5 mg, the incidence density of malignancies (excluding non-melanoma 
skin cancers) among RA patients treated with 5 mg BID for a maximum of 1 year was 
0.55/100 person-years (incidence rate 0.5% < 5/1216) [Xeljanz® Pharmaceutical Interview 
Form (in Japanese)]. 
These findings suggest that investigators pay particular attention to the possible development 
of infections and malignancies and take appropriate measures. Three cases of malignancies 
(stomach cancer, uterine sarcoma, chronic myelogenous leukemia) have been reported as of 
the cut-off date of 5 December 2013, from completed and ongoing national and international 
studies of ASP015K. Only the case of uterine sarcoma was judged as related to ASP015K. 
In the Japanese clinical trial in patients with moderate to severe RA (015K-CL-RAJ1), 50 mg 
and higher doses of ASP015K significantly improved the ACR20 response rate versus 
placebo. Xeljanz® (tofacitinib) 5 mg, which acts via the same mechanism as ASP015K, was 
approved by the US FDA in 2012 for the treatment of adult patients with moderate to severe 
RA who had an inadequate response to or are intolerant of MTX. In March 2013, Xeljanz® 
(tofacitinib) 5 mg tablets was authorized for marketing in Japan for treating RA patients who 
had an inadequate response to conventional therapies. Therefore, a potential benefit of JAK 
inhibitor ASP015K is to improve RA. 
One can also expect that long-term use of ASP015K will improve QOL of RA patients by 
successfully controlling the RA disease activity over an extended period. 
 

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2 
STUDY OBJECTIVE(S), DESIGN, AND VARIABLES 
2.1 
Study Objectives 
The objectives of this study are to verify the superiority of ASP015K alone or in combination 
with DMARDs over placebo in terms of efficacy, at doses of 100 mg/day and 150 mg/day, in 
patients with rheumatoid arthritis (RA) who had an inadequate response to DMARDs, as 
measured by the ACR20 response rate at Week 12, which is the primary variable; to evaluate 
the pharmacokinetics, pharmacodynamics, and safety of ASP015K; and to evaluate the 
efficacy and safety of long-term treatment with ASP015K (52 weeks). 
 
2.2 
Study Design and Dose Rationale 
2.2.1 
Study Design 
This is a Japanese, Korean and Taiwanese, multi-center, randomized, placebo-controlled, 
double-blind, parallel-group, confirmatory study to evaluate the efficacy and safety of 
ASP015K alone or in combination with DMARDs, at doses of 100 mg/day and 150 mg/day, 
in patients with RA who had an inadequate response to DMARDs. Open-label etanercept will 
also be administered as the reference drug for 52 weeks (the last dose will be given at Week 
51). In the study, ASP015K (test drug) and placebo (comparative drug) will be given as study 
drugs, and etanercept will be given as a separate reference drug. DMARD response is 
evaluated at the initiation of screening and then after the screening period, subjects will be 
randomized in a 1:1:1:2 ratio to the ASP015K 100 mg, ASP015K 150 mg, placebo, or 
reference groups, and they will receive either the study drug or reference drug for 52 weeks. 
Subjects in the ASP015K 100 mg, ASP015K 150 mg, and placebo groups will orally receive 
either ASP015K or placebo once daily after breakfast, while those in the reference group will 
receive 50 mg of subcutaneous etanercept once weekly. 
The planned sample size is 100 subjects each for the ASP015K 100 mg, ASP015K 150 mg, 
and placebo groups and 200 subjects for the reference group. 
Re-screening is allowed only in situations in which a subject underwent the screening 
procedures (i.e., scans and laboratory work) and owing to logistical circumstances, the 
allocated time window for these tests has expired. Re-screening is not permitted in cases in 
which the initial test results do not support eligibility based on inclusion and exclusion 
criteria. The subject must be classified as a screening failure at that time point.  
Any subject found not to meet the inclusion criterion (CRP) is permitted to undergo retest 
only once during the screening period. This however only applies to cases in which the CRP 
value measured at screening exceeds 0.30 mg/dL and the most resent CRP value measured at 
least 28 days before the screening procedures exceeds 0.5 mg/dL. 
Based on the consideration of the ethical issues related to long-term placebo use, at Week 12 
subjects in the placebo group will be switched to either ASP015K 100 mg or ASP015K 
150 mg, and the dosage will be maintained until the end of treatment. The ASP015K dose 

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that will be started for placebo group subjects at Week 12 (100 or 150 mg) will be randomly 
chosen at baseline. The dose will be switched under the blinded condition. 
Subjects in the ASP015K 100 mg, ASP015K 150 mg, or placebo groups who complete this 
study will be eligible for participation in the open-label extension study (015K-CL-RAJ2). 
Subjects will make a follow-up visit after the Week 52 visit if they do not enroll into the 
extension study on the day of the Week 52 visit. 
Safety data obtained from this study will be reviewed by the Independent Data and Safety 
Monitoring Board (DSMB), which will make recommendations on study continuation, 
termination, or protocol revision from the safety perspective. 
[Study Design Rationale] 
According to “Guidelines on methodology for clinical assessment of antirheumatic drugs” 
(PFSB/ELD Notification No. 0217001, dated 17 February 2006), the appropriate treatment 
period for clinical studies including a group taking a placebo alone is generally held to be 12 
weeks or less, and the Guidelines state that the study should be planned so that a sufficient 
investigation can be performed within this time frame. Taking note that 015K-CL-RAJ1 and 
clinical trials of similar drugs documented treatment responses sufficient for efficacy 
evaluation within 12 weeks of treatment, this study was designed to assess the ACR20 
response rate, a primary efficacy variable, at 12 weeks of treatment. 
After Week 12, all subjects in the placebo group are to receive the active drug, and according 
to the “Guidelines on methodology for clinical assessment of antirheumatic drugs” 
(PFSB/ELD Notification No. 0217001, dated 17 February 2006), the efficacy and safety of 
1-year treatment with ASP015K are to be assessed as secondary variables. As shown above, 
the duration of treatment was set at 52 weeks. 
2.2.2 
Dose Rationale 
[Dose Rationale] 
Study 015K-CL-RAJ1 evaluated the efficacy, safety, and dose response of ASP015K as 
single-agent therapy in RA patients. This study employed 25, 50, 100, and 150 mg doses. 
The primary efficacy variable of this study, the ACR20 response rate at Week 12 (or early 
termination), showed statistically significant improvements for 50 mg and higher doses 
relative to placebo, and dose-dependent improvements were noted up to 150 mg. Compared 
with placebo, statistically significant dose-dependent decreases in the DAS28-CRP score 
were observed for 50 mg, 100 mg, and 150 mg groups at Week 12 (or early termination).  
When the effect size between ASP015K versus placebo for the ACR20 response rate was 
compared with the effect sizes reported from clinical trials of a similar design (12- to 
14-week, double-blind, single-agent studies) conducted in Japan for other drugs, ASP015K 
100 mg or higher doses were likely to provide levels of efficacy comparable with those of 
other agents. 
AEs reported from 1 or more groups of Study 015K-CL-RAJ1 at ≥ 5% incidence rates were 
nasopharyngitis, rheumatoid arthritis aggravated, diarrhoea, constipation, blood creatine 

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phosphokinase increased, stomatitis, dyspepsia, lipids increased, and blood triglycerides 
increased. Compared with placebo, the incidence rates of AEs were not significantly elevated 
for the ASP015K groups. The reported AEs were mostly Grade 1 or Grade 2 by severity 
(NCI-CTCAE), involving a high proportion of events known as the class effect of JAK 
inhibitors. The ASP015K 150 mg group had the highest incidence rate of study-related AEs. 
This group had a particularly high incidence rate of blood creatine phosphokinase increased, 
reported in 7 subjects. AEs of increased CPK levels were mostly transient; in all the cases, 
the subjects recovered completely, including 1 subject who prematurely discontinued the 
study owing to logistic issues. No collateral symptoms suggestive of rhabdomyolysis or 
myopathy were detected. Although careful monitoring of CPK levels will be necessary for 
individual subjects of this Phase III study, currently available data suggest that 
ASP015K-induced changes in CPK are reversible and that subject safety associated with 
CPK changes can be properly monitored. The mean changes in CPK levels reported for the 
ASP015K and placebo groups were comparable with those reported from tofacitinib clinical 
trials. 
Ten SAEs were reported from 7 subjects; there was no characteristic pattern of occurrence, 
and no dose–response relationship was noted.  
Thus, the results of Study 015K-CL-RAJ1 raised no safety concerns with the use of 100 and 
150 mg/day doses in this Phase III study. 
With regard to efficacy, ACR20 response rate and DAS28 score, the primary variables of the 
Phase II study, showed dose-dependent improvements up to 150 mg, and the observed effects 
were statistically significant in comparison with placebo for 50 mg and higher doses. 
Comparison of published data [Enbrel® Pharmaceutical Interview Form, Simponi® 
Pharmaceutical Interview Form, Xeljanz® Pharmaceutical Interview Form, Humira® 
Pharmaceutical Interview Form] showed that 100 mg and higher doses of ASP015K could 
provide efficacy comparable with that of the approved doses of similar drugs, supporting the 
validity of using 100 mg and higher doses in this Phase III study. From the safety perspective, 
the results of Study 015K-CL-RAJ1 confirmed the tolerability of ASP015K doses up to 
150 mg.  
Based on the abovementioned discussion, 100 and 150 mg/day doses were selected for this 
Phase III clinical trial.  
The dose of etanercept was set at 50 mg/week, which is commonly used in Japan and 
recommended in the US package insert. 
[Rationale for the Mode of Administration] 
Nonclinical study results showed that AUC was the most important pharmacokinetic 
parameter for characterizing the therapeutic effect of ASP015K. While admitting that 
015K-CL-PS01 focused on a clinical condition different from that of this Phase III study, this 
clinical trial conducted in patients with psoriasis demonstrated no significant differences 
between 50 mg QD and 25 mg BID doses of ASP015K.  

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In Study 015K-CL-RAJ1, ASP015K was administered once daily after breakfast. This 
method of administration was based on the idea that the desired efficacy could be achieved 
regardless of the differences in the mode of administration, as long as the target AUC is 
attained. In addition, this method of administration was favorable from the view point of 
subject convenience, medication adherence, and other aspects of study implementation. 
Study 015K-CL-RAJ1 showed excellent medication adherence and demonstrated the efficacy 
of ASP015K in terms of the ACR20 response rate and other outcome measures. Therefore, 
administration once daily after breakfast was also adopted in this clinical trial. 
 
2.3 
Variables 
2.3.1 
Primary Variables 
● 
ACR20 response rate at Week 12 
 [Rationale] 
Taking note of the “Guidelines on methodology for clinical assessment of antirheumatic 
drugs,” and “Guidance for Industry Rheumatoid Arthritis: Developing Drug Products for 
Treatment”, the ACR20 response rate, an indicator of RA disease activity and response to 
treatment, was chosen as a primary variable. The evaluation time point was set at Week 12 of 
treatment on the basis of the guidelines. 
2.3.2 
Secondary Variables 
2.3.2.1 Secondary Efficacy Variables 
● 
ACR20 response rate 
● 
ACR50 response rate 
● 
ACR70 response rate 
● 
Change from baseline in DAS28-CRP and DAS28-ESR scores 
● 
Change from baseline in TJC (68 joints) 
● 
Change from baseline in SJC (66 joints) 
● 
Percentage of subjects achieving DAS28-CRP and DAS28-ESR scores for remission 
● 
Percentage of subjects achieving low disease activity by DAS28-CRP and DAS28-ESR 
● 
Change from baseline in CRP and ESR 
● 
Percentage of subjects with good EULAR response 
● 
Percentage of subjects with good or moderate EULAR response 
● 
Percentage of subjects achieving ACR/EULAR remission 
If all of the following 4 parameters are fulfilled, it is defined as remission: 
 TJC ≤ 1 
 SJC ≤ 1 
 CRP ≤ 1 mg/dL 
 Subject’s Global Assessment of Arthritis (SGA) ≤ 1 cm (on a VAS of 0-100 mm) 
● 
Percentage of subjects achieving SDAI remission (SDAI score ≤ 3.3)  
● 
Change from baseline in SDAI score 
● 
Change from baseline in Physician’s Global Assessment of Arthritis (PGA) (VAS) 

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● 
Change from baseline in SGA (VAS) 
● 
Change from baseline in subject’s assessment of pain (VAS) 
● 
Incidence of subject withdrawal due to the lack of efficacy 
● 
Change from baseline in HAQ-DI score 
● 
Change from baseline in SF-36v2® score 
● 
Change from baseline in WPAI score 
2.3.2.2 Safety Variables 
● 
AEs 
● 
Vital signs (body temperature, pulse rate, and blood pressure in sitting a position) 
● 
Body weight 
● 
12-lead ECG 
● 
Central ECG 
● 
Chest radiography 
● 
Laboratory assessments 
2.3.2.3 Pharmacokinetics Variables 
Plasma ASP015K concentration 
2.3.2.4 Pharmacodynamics Variables 
● 
Change from baseline in MMP-3 level 
● 
Change from baseline in VEGF level 
● 
Change from baseline in lymphocyte subset assays (CD3, CD4, CD8, CD16, CD19, 
CD56, CD56/16) 
2.3.2.5 Pharmacogenomics (Bio-Banking) [unique to Japan and Korea] 
To prepare for future research to analyze the relationship between genes and the efficacy, 
safety, or pharmacokinetics of the study drug, blood sample will be collected and stored with 
the consent of the subject in Japan and Korea. 
2.3.3 
Other Variables 
Not applicable. 
 

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3 
STUDY POPULATION 
3.1 
Selection of Study Population 
The target population for this study is patients with RA who had an inadequate response to 
DMARDs. 
 
3.2 
Inclusion Criteria 
Subject is eligible for the study if all of the following apply: 
1. Subject has received a full explanation of the study drug and this study in advance, and 
written informed consent to participate in the study has been obtained from the subject 
himself/herself. 
2. Subject is a man or woman aged ≥ 20 years at the time of informed consent. 
3. Subject has RA diagnosed according to the 1987 American College of Rheumatology 
(ACR) criteria or the 2010 American College of Rheumatology/European League against 
Rheumatism (ACR/EULAR) criteria. 
4. Subject who did not receive the following drugs, or received the drugs with stable 
dosage for at least 28 days prior to the baseline (start of treatment) for RA treatment: 
Non-steroidal anti-inflammatory drugs (NSAIDs; excluding topical formulations), oral 
morphine or equivalent opioid analgesics (≤ 30 mg/day), acetaminophen, or oral 
corticosteroids (≤ 10 mg/day in prednisolone equivalent). 
5. At screening subject has active RA as evidenced by both of the following: 
• 
≥ 6 tender/painful joints (using 68-joint assessment) 
• 
≥ 6 swollen joints (using 66-joint assessment) 
6. CRP > 0.50 mg/dL at screening. 
7. Subject meets the ACR 1991 Revised Criteria for the Classification of Global Functional 
Status in RA Class I, II, or III at screening. 
8. Inadequate responder to (including subjects who were intolerant of) at least one 
DMARD administered for at least 90 days prior to screening. 
9. When the following DMARDs are concomitantly administered to subject, the drugs must 
be administered for at least 90 days prior to screening, and must be stable from at least 
28 days prior to screening until the end of the administration period of study drug or 
reference drug. 
• 
Methotrexate (MTX) 
• 
Hydroxychloroquine 
• 
Salazosulfapyridine 
• 
Gold 
• 
D-penicillamine 
• 
Lobenzarit 
• 
Actarit 
• 
Bucillamine 
• 
Iguratimod 

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10. Subject must be willing and able to comply with the study requirements. 
 
[Rationale for Inclusion Criteria] 
1: Established with consideration for ethics of conducting the study. 
2: Established to ensure ethical and safe conduct of the study. 
3: Established to select RA patients relevant for this study. Taking note of the recent changes 
in RA diagnostic criteria and current practices in clinical settings, patients conforming to 
either the 1987 ACR or the 2010 ACR/EULAR criteria have been defined eligible for 
inclusion.  
4: Established because these drugs are used to improve QOL of RA patients and may 
possibly impact the efficacy evaluation of ASP015K.  
5 and 6: Established to define the range of RA disease activity pertinent to this study.  
7: Established to identify patients appropriate for evaluation using the classification criteria 
for functional status.  
8: Established to select patients who had an inadequate response to the protocol-specified 
DMARDs.  
9: Established to choose patients who can maintain the same dosage and administration 
schedule for the specified concomitant DMARDs from before baseline and throughout the 
treatment period. 
10: Established to ensure the integrity of the study evaluation. 
 
3.3 
Exclusion Criteria 
Subject will be excluded from participation if any of the following applies: 
1. Subject has received a biologic DMARD within the specified period: 
• 
Anakinra: within 28 days prior to baseline 
• 
Adalimumab, infliximab: within 56 days prior to baseline 
• 
Golimumab, certolizumab pegol: within 70 days prior to baseline 
• 
Abatacept, tocilizumab: within 84 days prior to baseline 
• 
Denosumab: within 150 days prior to baseline 
• 
Rituximab: within 180 days prior to baseline 
2. Subject has received etanercept. 
3. Inadequate responder to at least 3 biologic DMARDs as determined by 
investigator/sub-investigator. 
4. Subject has received a non-biologic DMARD listed below or other drugs used in the 
treatment of RA within 28 days prior to baseline. Leflunomide is prohibited within 180 
days prior to baseline. Alternatively, leflunomide is prohibited within 28 days prior to 
baseline if washout with cholestyramine for at least 17 days is completed at least 28 days 

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prior to baseline. However, topical drugs other than those for the treatment of RA may 
be used concomitantly. 
• 
Leflunomide 
• 
Tacrolimus 
• 
Cyclosporine 
• 
Cyclophosphamide 
• 
Azathioprine 
• 
Minocycline 
• 
Mizoribine 
5. Subject has received tofacitinib or other JAK inhibitor (including other investigational 
drugs). 
6. Subject has received intra-articular, intravenous, intramuscular, or endorectal (excluding 
suppositories for anal diseases) corticosteroid within 28 days prior to baseline. 
7. Subject has participated in any study of ASP015K and has received ASP015K or 
placebo. 
8. Subject has received other investigational drugs within 90 days or within 5 half-lives, 
whichever is longer, prior to baseline. 
9. Subject has received plasma exchange therapy within 60 days prior to baseline. 
10. Subject has undergone joint drainage, has received local anesthesia and nerve block, or 
has received articular cartilage protectant at the assessed joint within 28 days prior to 
baseline. 
11. Subject has undergone surgery and has residual effects in the assessed joints at the 
discretion of investigator/sub-investigator, or is scheduled to undergo surgery that may 
affect the study evaluation of the assessed joints at the discretion of 
investigator/sub-investigator. 
12. A diagnosis of inflammatory arthritis (psoriatic arthritis, ankylosing spondylitis, SLE, 
sarcoidosis, etc.) other than RA. 
13. Any of the following laboratory values during the screening test period: 
• 
Hemoglobin < 9.0 g/dL 
• 
Absolute neutrophil count < 1000/µL 
• 
Absolute lymphocyte count < 800/µL 
• 
Platelet count < 75000/µL 
• 
ALT ≥ 2 × ULN 
• 
AST ≥ 2 × ULN 
• 
Total bilirubin (TBL) ≥ 1.5 × ULN 
• 
Estimated GFR ≤ 40 mL/min as measured by the MDRD method 
• 
β-D-glucan > ULN [in case of Japan: ≥ 11 pg/mL] 
• 
Positive HBs antigen, HBc antibody, HBs antibody or HBV-DNA quantitation 
(However, subject with negative HBs antigen and HBV-DNA quantitation, and 
positive HBc antibody and/or HBs antibody is eligible if HBV-DNA is monitored 
by HBV-DNA quantitation at every scheduled visit after initiation of study drug or 
reference drug administration.) 
• 
Positive HCV antibody 

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14. Subject has a history of or concurrent active tuberculosis (TB). Eligibility criteria for TB 
are tabulated below: 
History of active 
TB 
Chest x-ray 
(for TB) 
TB infectionb) 
Exposure to patients with 
infective TB (interview) 
Eligibility 
Present 
- 
- 
- 
Not eligible 
Absent 
Abnormal (active) 
- 
- 
Not eligible 
Abnormal (old)a) 
- 
Eligible 
Eligible if  
prophylaxis is givenc) 
Normal 
Positive 
Eligible 
Eligible if  
prophylaxis is givenc) 
Negative 
Exposed 
Eligible if  
prophylaxis is givenc) 
Not exposed 
Eligible 
a) Old TB is evidenced if chest x-ray reveals pleural thickening, band-like shadow, and calcification ≥ 5 mm. 
Chest x-ray within 90 days prior to baseline may substitute the screening test. 
b) T-spot or Quantiferon Gold test is of first priority. When the result is equivocal or invalid, retest including 
other test methods may be allowed. If a retest is not performed, criteria for positive results will be followed. 
When T-spot or Quantiferon Gold test is not feasible, tuberculin test will be performed. Tuberculin is defined as 
positive with a red spot covering an area of 20 mm or more or induration. Tests conducted within 90 days prior 
to baseline may be used for diagnosis. 
c) Subject must receive or have received prophylaxis with isoniazid or rifampicin. Prophylaxis will be 
administered for 6 to 9 months, starting from at least 21 days prior to baseline. 
 
15. Subject meets any of the following in terms of infections except for TB: 
• 
History of or concurrent severe herpes zoster (associated with Hunt syndrome or 
having ulcerative lesions) or disseminated herpes zoster 
• 
History of multiple recurrences (at least twice) of localized herpes zoster 
• 
Serious infection requiring hospitalization within 90 days prior to baseline 
• 
Subject has received intravenous antibiotics within 90 days prior to baseline. 
(However, prophylactic antibiotics are allowed.) 
• 
Subject with high risk of infection (e.g., subject with urinary catheter) at the 
discretion of investigator/sub-investigator 
16. Subject has a history of or concurrent interstitial pneumonia and 
investigator/sub-investigator judges that it is inappropriate for the subject to participate 
in this study. 
17. Subject has a history of or concurrent malignant tumor (except for successfully treated 
basal cell carcinoma). 
18. Subject has received live or live attenuated virus vaccination within 56 days prior to 
baseline. (Inactivated vaccines including influenza and pneumococcal vaccines are 
allowed.) 
19. Subject has a history of or concurrent demyelinating disorders. 
20. Subject has any ongoing severe, progressive, or uncontrolled renal, hepatic, 
hematological, gastrointestinal, metabolic, endocrine, pulmonary, cardiac, neurological, 
infectious, or autoimmune disease except for RA (excluding Sjogren’s syndrome and 
chronic thyroiditis), or any ongoing illness which would make the subject unsuitable for 
the study as determined by the investigator/sub-investigator. 

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21. Subject has a history of clinically significant allergy. (Clinically significant allergy 
includes allergies such as systemic urticaria induced by specific antigens and drugs, 
anaphylaxis, and allergy associated with shock necessitating hospitalized treatment.) 
22. Subject has received medications that are CYP3A substrates with narrow therapeutic 
range within 14 days prior to baseline. These medications include: dihydroergotamine, 
ergotamine, fentanyl, pimozide, quinidine, temsirolimus, and disopyramide. 
23. Subject has concurrent cardiac failure, defined as NYHA classification Class III or 
higher, or a history of it. 
24. Subject has concurrent prolonged QT syndrome or a history of it. Subject has prolonged 
QT interval (defined as QTc ≥ 500 msec. Subject has QTc ≥ 500 msec at retest will be 
excluded) at screening. 
25. Subject has a history of positive HIV infection. 
26. Subject is a woman who is pregnant or might be pregnant, is nursing, wishes to conceive 
for a period running from the time informed consent is given within 60 days after end of 
treatment (including reference drug), or for whom the possibility of pregnancy cannot be 
ruled out as a result of the serum pregnancy test given at the time of screening. 
27. Subject is a man who cannot practice at least 2 types of contraception from the time of 
informed consent to 90 days after end of treatment (including reference drug), or subject 
is a woman with childbearing potential who cannot practice at least 2 types of 
contraception from the time of informed consent to 60 days after end of treatment 
(including reference drug). 
28. Male subject who do not agree not to donate sperm starting at informed consent and 
through the treatment period and for at least 90 days after final study drug (or reference 
drug) administration. Female subject who do not agree not to donate ova starting at 
informed consent through the treatment period and for 60 days after final study drug (or 
reference drug) administration. 
29. The subject has been judged unsuitable to participate in the study for other reasons by 
the investigator/sub-investigator. 
30. The subject has a history or complication of lymphatic diseases such as 
lymphoproliferative disorder, lymphoma, and leukemia. 
31. Subject has congenital short QT syndrome or a history of it. Subject has shortened QT 
interval (defined as QTc < 330 msec. Subject has QTc < 330 msec at retest will be 
excluded) at screening. 
 
[Rationale for exclusion criteria] 
1, 4, 5, 6, 7, 8: Established to eliminate confounding factors affecting evaluation. 
2: Established in consideration of the efficacy of etanercept. 
3, 9, 10, 11, 12: Established to eliminate confounding factors affecting efficacy evaluation. 
13, 14, 15, 16, 17, 18, 20, 21, 22, 23, 24, 25, 26, 27, 28, 30, 31: Established out of safety 
concerns. 

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19: Established in consideration of the safety of subjects, because etanercept is 
contraindicated in patients who previously had or currently have demyelinating disorders. 
29: Established in anticipation for a case where the investigator/sub-investigator judges a 
patient to be inappropriate for participation in the study. 
31: The QTc criterion is quoted from Expert Consensus [Silvia G. Priori, 2014] of 
HRS/EHRA/APHRS. 
 
3.4 
Discontinuation Criteria for Individual Subjects 
A discontinuation is a subject who enrolled in the study and for whom study treatment is 
permanently prematurely discontinued for any reason. 
The subject is free to withdraw from the study treatment and/or study for any reason and at 
any time without giving reason for doing so and without penalty or prejudice. The 
investigator is also free to terminate a subject’s involvement in the study at any time if the 
subject’s clinical condition warrants it. 
The Appendix 4 entitled “Liver Safety Monitoring and Assessment” describes liver function 
tests raised that provide grounds for discontinuation. Refer to Appendix 4 concerning the 
measures to take for increases in liver function test parameters. 
 
The investigator/sub-investigator should discontinue the study if any of the following occurs: 
1. The subject withdraws consent. 
2. The investigator/sub-investigator judges that the study drug or reference drug is not 
sufficiently effective and the treatment method needs to be changed. 
3. Symptomatic CPK elevation (> 1.5 × ULN accompanied with severe and unusual 
episodes of myalgia, muscular weakness, or muscle twitching). 
4. Any case of myopathy involving severe and unusual episodes of myalgia, muscular 
weakness, or muscle twitching that persists for no less than, or aggravates rapidly within, 
2 weeks, regardless of the CPK level.  
5. A previously HBV-infected patient with positive HBc antibody, positive HBs antibody, 
or both has been shown positive for HBV-DNA during the study. 
Attention should be paid that abrupt discontinuation of immunotherapy may cause 
fulminant or severe liver failure. Therefore, if the subject manifests HBV reactivation, 
the investigator/sub-investigator will administer nucleoside analogs without delay 
[unique to Japan: according to the “Proposal for Management of Rheumatic Disease 
Patients with Hepatitis B Virus Infection Receiving Immunosuppressive Therapy” 
(Japan College of Rheumatology)]. The investigator/sub-investigator will carefully 
decide whether to continue or discontinue the study drug, reference drug, and 
concomitant DMARDs in consultation with the hepatology specialist. 
6. Malignant tumor 

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7. The subject develops a serious infection or other AEs, and continued administration of 
the study drug is not deemed appropriate in the subject’s best interest by the 
investigator/sub-investigator. 
8. The subject has been treated with a prohibited concomitant drug or therapy (including 
another investigational product) that may impact efficacy evaluation. The subject has 
been, or needs to be, treated with a rescue medication for a period extending beyond its 
allowable time. Otherwise, the subject has been, or needs to be, treated with a live or live 
attenuated vaccine. 
9. The subject has been judged by the investigator/sub-investigator to be non-compliant to 
the medication requirements for treatment with the study drug, concomitant DMARDs, 
or reference drug injection. 
10. The subject is deemed incapable of continuing the follow-up based on the opinion of the 
investigator/sub-investigator (subject can no longer come to the study center; subject can 
no longer be contacted, etc.). 
11. It comes to light after the administration of the first dose of study drug or reference drug 
that inclusion criteria were not met at the time of case enrollment or that criteria for 
exclusion were met. It comes to light that there was some other major deviation from the 
protocol. 
12. The subject needs the study drug or reference drug to be interrupted beyond its allowable 
time limit. 
13. Investigator/sub-investigator decides it is in the subject’s best interest. 
14. The sponsor has requested that the study be discontinued because of a safety concern in a 
particular subject, or the sponsor has decided to discontinue the study altogether. 
15. The Subject shows QTc interval < 300 msec at central ECG, or the subject shows QTc 
interval < 300 msec at the site’s ECG and also shows QTc interval < 300 msec at retest. 
 
Subjects who discontinue early from the study should be given the necessary tests and 
assessments specified for early termination within 2 days of withdrawal. They should also 
undergo follow-up tests and assessments. Subjects with early termination will be treated as 
discontinuations, and the investigator/sub-investigator must make clear the reason for 
discontinuation and the day of early termination (the date on which the 
investigator/sub-investigator has decided to discontinue the subject) as well as retain all 
clinical study data on the discontinuations and submit them to the sponsor in eCRF, etc. 
3.4.1 
Suspension, Interruption, and Resumption of the Study Drug or Reference 
Drug 
During treatment with the study drug or reference drug, if the subject meets any of the 
criteria provided in Section 3.4.1.1 Criteria for Suspension or Interruption of the Study Drug 
or Reference Drug, the investigator/sub-investigator will immediately suspend or interrupt 
the study drug or reference drug. The investigator/sub-investigator can resume treatment with 
the study drug or reference drug only if re-examinations and other assessments performed 
after the suspension or interruption confirm that none of the conditions listed below are 

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applicable to the subject and the investigator/sub-investigator considers it desirable for the 
interest of the subject on the basis of risk-benefit analysis. 
 
The maximum allowable time for “suspension” is 7 days for the study drug and a week (1 
dose per week) for the reference drug. If the treatment is halted beyond the suspension period, 
i.e., longer than 7 days for the study drug or skipping more than 1 dose for the reference drug, 
the period of no treatment is categorized as an “interruption.”  
Upper limits have been set to the number of interruptions 1 subject can have and to the 
duration of 1 interruption. One interruption period may last for 28 days for the study drug and 
4 weeks (i.e., 4 consecutive doses) for the reference drug. One subject is allowed to have a 
maximum of 2 interruptions, which must be separated by 16 or more weeks.  
 
The investigator will consult the sponsor regarding the handling of a subject who repeatedly 
requires treatment suspension. 
The subject must be withdrawn from the study, if he or she requires either a third interruption 
or a second interruption within less than 16 weeks from the first one. 
3.4.1.1 Criteria for Suspension or Interruption of the Study Drug or Reference Drug 
The investigator/sub-investigator will immediately suspend or interrupt the study drug or 
reference drug if any of the following becomes applicable during treatment with the study 
drug or reference drug: 
1. Clinical laboratory tests yielded any of the following results: 
• 
Hemoglobin < 8.0 g/dL 
• 
Absolute neutrophil count < 500/µL 
• 
Absolute lymphocyte count < 500/µL 
• 
Platelet count < 50000/µL 
• 
Creatinine (serum) levels measured at 2 consecutive hospital visits: above 150% of 
the baseline level 
• 
CPK > 10 × ULN 
2. β-D-glucan > ULN [in case of Japan: ≥ 11 pg/mL] 
3. The subject requires a medication whose concomitant administration is prohibited in the 
protocol because of possible drug-drug interaction. 
4. The subject is suspected to be pregnant. 
5. The investigator/sub-investigator judged it appropriate in the interest of the subject to 
suspend or interrupt the study drug or reference drug. 
6. The sponsor made a request to suspend or interrupt the study drug or reference drug out 
of safety concerns for the subject. 
 

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4 
STUDY DRUGS OR REFERENCE DRUGS 
4.1 
Description of Study Drugs or Reference Drugs 
The test drugs for this study are ASP015K tablets of 100 mg and 150 mg. The comparative 
drugs are ASP015K tablet placebos of 100 mg and 150 mg. The reference drug is an 
etanercept (recombinant) 50 mg syringe (1.0 mL). 
4.1.1 
Test Drug(s) 
Code name 
ASP015K 
Generic name 
Peficitinib hydrobromide 
Chemical name 
4-{[(1R,2S,3S,5S,7S)-5-hydroxy-2-adamantyl]amino}-1H-pyrrolo[2,3-b]
pyridine-5-carboxamide monohydrobromide 
Molecular formula 
(molecular weight) 
C18H22N4O2 · HBr (407.30) 
Content and dosage form 
ASP015K tablet 100 mg: An elliptical, pale-red film coated tablet 
containing the ASP015K drug substance at 100 mg (as free form) 
ASP015K tablet 150 mg: An elliptical, yellow, film-coated tablet 
containing the ASP015K drug substance at 150 mg (as free form) 
Manufacturer 
Astellas Pharma Inc. (API) 
Lot No. 
Noted in SOP for handling of study drugs 
Storage method 
Store at room temperature 
Expiration date 
Noted in SOP for handling of study drugs 
4.1.2 
Comparative Drug(s) 
Code name 
ASP015K 
Content and dosage form 
ASP015K tablet 100 mg placebo: An elliptical, pale-red film coated 
tablet indistinguishable from the ASP015K tablet 100 mg 
ASP015K tablet 150 mg placebo: An elliptical, yellow, film-coated 
tablet indistinguishable from the ASP015K tablet 150 mg 
Manufacturer 
Astellas Pharma Inc. (API) 
Lot No. 
Noted in SOP for handling of study drugs 
Storage method 
Store at room temperature 
Expiration date 
Noted in SOP for handling of study drugs 
4.1.3 
Reference Drug(s) 
Generic name 
Etanercept (recombinant) 
Chemical name 
1-235-Tumor necrosis factor receptor(human)fusion protein with 
236-467-immunoglobulin G1(humanγ1-chain Fc fragment),dimer 
Molecular formula 
(molecular weight) 
Molecular weight: approximately 150,000 
Total number of amino acids: 934 
Content and dosage form 
Etanercept 50 mg syringe (1.0 mL) 
Manufacturer 
 
Lot No. 
Noted in SOP for handling of study drugs 
Storage method 
Do not freeze and store at 2°C to 8°C protected from light. 
Expiration date 
Noted in SOP for handling of study drugs 
 

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4.2 
Packaging and Labeling 
All medications used in this study will be manufactured, packaged, and labeled under the 
responsibility of the Quality Assurance Manager in accordance with sponsor’s Standard 
Operating Procedures (SOP), GMP guidelines, GCP and applicable local laws/regulations. 
(Refer to the study drug handling manual for details) 
(Packaging form) 
The study drugs will be packaged in a small box containing 28 day’s worth of medication 
and 7 day’s worth of spare medication. One PTP sheet (aluminium/aluminium) holds a total 
of 14 tablets: 7 tablets of ASP015K at 100 mg or placebo for ASP015K at 100 mg and 7 
tablets of ASP015K at 150 mg or placebo for ASP015K at 150 mg. Five PTP sheets 
(including 1 spare sheet) will be packaged in the small box. 
Reference drugs will be supplied in 2 commercially available cartons containing 2 syringes 
each. 
 
In case of Japan (Package design of study drug and reference drug for Korea and Taiwan is 
described in the study drug handling manual): 
(Study drug) 
 
 
Lot No.●● 
70 tablets (14 tablets × 5 sheets) 
Phase III Study of ASP015K (DBT) 
(015K-CL-RAJ3) 
 
 
 
Caution: 1. Please retain any remaining medication and this box without discarding them until 
they are collected by the sponsor. 
2. Please make certain that the medication allocated for each patient is used for the 
same patient and is not used for any other patient. 
Storage method: Store at room temperature  
Expiration date: Specified in SOP for handling of the study drugs 
 
Astellas Pharma Inc. (API) 
2-5-1 Nihonbashi-Honcho, Chuo-ku, Tokyo 
 
 
 
 
 
 
 
For clinical trial 

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(Reference drug) 
 
 
Lot No.●● 
4 syringes (2 syringes × 2 cartons) 
Phase III Study of ASP015K (Reference drug) 
(015K-CL-RAJ3) 
 
Etanercept 50 mg 1.0 mL 
 
Caution:  
Please retain any remaining medication and this box without discarding them until 
they are collected by the sponsor. 
Storage method: Do not freeze and store at 2°C to 8°C protected from light 
Expiration date: Specified in SOP for handling of the study drugs 
 
Astellas Pharma Inc. (API) 
2-5-1 Nihonbashi-Honcho, Chuo-ku, Tokyo 
 
 
 
 
 
 
Lot No. is noted in SOP for handling of study drugs. 
 
4.3 
Study/Reference Drug Handling 
Japan: 
The head of the study center or the study drug storage manager should take accountability of 
the study drugs or reference drugs as following issues. 
● 
The study drug storage manager should store and take accountability of the study drugs 
or reference drugs in conforming to the procedures for handling the study drugs written 
by the sponsor. 
● 
The study drug storage manager should prepare and retain records of the study drug’s 
receipt, the inventory at the study center, the use by each subject, and the return to the 
sponsor or alternative disposal of unused study drugs or reference drugs. These records 
should include dates, quantities, batch/serial numbers, expiration dates (if applicable), 
and the subject identification codes. 
● 
The study drug storage manager should prepare and retain records that document 
adequately that the subjects were provided the doses specified by the protocol, and 
reconcile all the study drugs or reference drugs supplied from the sponsor. 
Korea and Taiwan: 
The procedures will be specified separately in the study drug handling manual in accordance 
with the local requirements. 
 
4.4 
Blinding 
4.4.1 
Blinding Method 
Treatment allocation to the ASP015K 100 mg, ASP015K 150 mg, or placebo groups is 
double-blinded. The ASP015K tablet 100 mg, ASP015K tablet 100 mg placebo, or ASP015K 
For clinical trial 

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tablet 150 mg, ASP015K tablet 150 mg placebo are indistinguishable from each other in 
appearance, and the packaging for each treatment group (100 mg, 150 mg, and placebo) is 
also indistinguishable from that for other groups in appearance. The treatment code will only 
be known to the person responsible for assigning study drugs, person appointed at the 
institution performing measurements of plasma drug concentrations, persons in the Safety 
Control Division when necessary for Suspected Unexpected Serious Adverse Reaction 
(SUSAR) handling, and independent Data and Safety Monitoring Board (DSMB). 
No blinding will be performed for the reference group. 
4.4.2 
Confirmation of the Indistinguishability of the Study Drugs 
The appearance and the form of both the drug and packaging of the ASP015K tablet 100 mg 
and ASP015K tablet 150 mg are identical to those of their matching placebo. [unique to 
Japan: The person responsible for assigning study drugs will confirm the indistinguishability 
of the study drugs and their packaging in appearance before the assignment of the study 
drugs and during the period from collection of the study drugs to the breaking of the 
treatment code]. 
4.4.3 
Retention of the Assignment Schedule and Procedures for Treatment Code 
Breaking 
The person responsible for assigning study drugs will create a randomization list (original 
document) plus 3 copies (reproductions) for Japan and Korea/Taiwan separately in advance 
of the assignment of the study drug and seal each separately. The person responsible for 
assigning study drugs will retain the original randomization list. One copy of the 
randomization list (reproduction) will be retained by the sponsor in a sealed state even after 
the breaking of the treatment code, one copy will be prepared for use by DSMB, and the third 
copy will be provided to the institution performing measurements of plasma drug 
concentrations by the person responsible for assigning study drugs to be used as a sample 
measurement instruction sheet bearing treatment code information. 
The person responsible for assigning study drugs will also create a treatment code for 
emergency and provide it to the person responsible for managing the treatment code for 
emergency. The person responsible for managing the treatment code for emergency will 
manage individual treatment code for emergency with code breaking permission in the 
web-based system. The web treatment code system can only be accessed by the person 
responsible for managing treatment code for emergency, the sponsor’s responsible personnel 
(or sponsor), and the person in charge of the Safety Control Division when necessary for 
SUSAR handling. The “SOPs for the Phase III Study of ASP015K DSMB” should be 
followed for treatment code retention, breaking, and code information conservation at the 
time of safety data review and safety evaluation. 
4.4.4 
Breaking the Treatment Code for Emergency 
In the event of a medical emergency requiring knowledge of the treatment assigned to the 
subject, the investigator/sub-investigator can ask the sponsor to break the treatment code for 
emergency for the subject in question. The sponsor will make the decision as to whether or 

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not to break the treatment code for emergency. The “SOPs for breaking the treatment code 
for emergency in Phase III study of ASP015K (015K-CL-RAJ3)” should be followed when 
the treatment code is broken. The investigator/sub-investigator, sponsor, and the person 
responsible for managing the treatment code for emergency should maintain contact so that 
the treatment code can be broken immediately in an emergency. When a sub-investigator 
requests that the treatment code be broken in an emergency, the consent of the investigator 
should in principle be obtained in advance. However, in cases where it is difficult to obtain 
the understanding of the investigator in advance, the sub-investigator should immediately 
report the request to break the treatment code for an emergency to investigator after the fact. 
After the treatment code has been broken by the investigator or other responsible personnel, 
the study center must report the breaking of the treatment code and the reason for doing so to 
the contacts listed in the “Section II CONTACT DETAILS OF KEY SPONSOR’S 
PERSONNEL.” 
4.4.5 
Breaking the Treatment Code by the Sponsor 
The sponsor may break the treatment code for subjects who experience SUSAR if regulatory 
reporting is considered necessary. An individual emergency code will be provided to the 
limited staff who are empowered to break the code for all SUSAR cases for reporting 
purposes. 
 
4.5 
Assignment and Allocation 
The person responsible for assigning study drugs will randomly assign the study drugs and 
retain the treatment code under secrecy until the breaking of the treatment code.  
The Case Registration Center will assign subjects who have been found to be eligible for 
enrollment in accordance with the case registration procedures to 1 of the following groups: 
ASP015K 100 mg, ASP015K 150 mg, placebo, or reference groups at baseline in 1:1:1:2 
ratio. At Week 12, subjects in the placebo group will be switched to receiving either 
ASP015K at a dose of 100 mg or ASP015K at a dose of 150 mg. The dose of ASP015K (100 
mg or 150 mg) to be administered to the placebo group from Week 12 will be determined in 
advance randomly at baseline, and study drugs must be switched under double-blind 
conditions. 
To minimize potential bias in this study, dynamic allocation procedures in each study region 
(Japan, Korea, and Taiwan) will be used by biased-coin minimization with the following 1 to 
3 as factors: 
1. Study center; 
2. Prior biologic DMARD-IR at baseline; and 
3. Concomitant DMARD use at the initiation of treatment with the study drug or reference 
drug. 
All drug numbers are assigned randomly by the Case Registration Center under blind 
conditions. 

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5 
TREATMENTS AND EVALUATION 
5.1 
Dosing and Administration of Study Drugs or Reference Drugs and 
Other Medications 
5.1.1 
Dose/Dose Regimen and Administration Period 
(1) 
Dose and administration period 
The following 4 treatment groups will be set up: ASP015K 100 mg group, ASP015K 150 mg 
group, placebo group, and reference group.  
The dose for each treatment group is shown in the table below. Two tablets of the drug 
described in the table below will be administered QD. The administration period will be 52 
weeks. At Week 12, subjects in the placebo group will be switched to receivingeither 
ASP015K at a dose of 100 mg or ASP015K at a dose of 150 mg under blind conditions. The 
dose of ASP015K to be administered to the placebo group from Week 12 will be determined 
in advance at baseline and will be continued until Week 52. 
For the reference group, open-label etanercept will be administered for 52 weeks. 
Table Treatment Periods and Doses by Treatment Period (Administered Drug) in Study 
015K-CL-RAJ3 
 
Baseline–Week 121) 
Week 12–Week 52 
Placebo group 
ASP015K placebo 
(ASP015K tablet 100 mg  
placebo and  
ASP015K tablet 150 mg placebo) 
100 mg/day as ASP015K 
(ASP015K tablet 100 mg  
and  
ASP015K tablet 150 mg  
placebo) 
150 mg/day as ASP015K 
(ASP015K tablet 100 mg  
placebo  
and ASP015K tablet 150 mg) 
ASP015K 100 mg group 
100 mg/day as ASP015K 
(ASP015K tablet 100 mg and ASP015K tablet 150 mg placebo) 
ASP015K 150 mg group 
150 mg/day as ASP015K 
(ASP015K tablet 100 mg placebo and ASP015K tablet 150 mg) 
Reference group 
Etanercept 50 mg/week (the last dose will be given at Week 51.) 
1) At Week 12, subjects in the placebo group will be assigned to receiving either ASP015K 100 mg or 
ASP015K 150 mg. Subjects will continue receiving the assigned dose thereafter. 
 
(2) 
Mode of administration 
[ASP015K 100 mg, ASP015K 150 mg, and placebo groups] 
The assigned study drug will be orally administered to subjects under double-blind 
conditions QD after breakfast. The baseline dose should be given at each study center on the 
day of the baseline visit after all assessments and tests are completed. 
Doses on the day of scheduled visits during treatment with the study drug or reference drug 
should be given on the day of the visit after all assessments and tests are completed, except 
for blood sampling for the assessment of post-dose concentrations. 

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[Reference group] 
The reference drug will be subcutaneously administered to subjects once weekly (the last 
dose will be given at Week 51). The baseline dose should be given at each study center on 
the day of the baseline visit after all assessments and tests are completed. After the baseline 
visit, the reference drug will be given taking the same day of the week at baseline as the 
reference date. The acceptable time range for administration of the reference drug will be 
within ± 6 days of the reference date, and if the reference drug is given beyond the acceptable 
time range, it will be regarded as unadministered. The reference drug should also be 
administered at a minimum of 3-day intervals. 
Doses on the day of scheduled visits during treatment with the study drug or reference drug 
should be given on the day of the visit after all assessments and tests are completed. 
The reference drug may be given at any time on administration days (in-hospital 
administration and self-administration), except those of scheduled visits. 
Etanercept can be self-administered only by the subject who has been provided with adequate 
education and training by the study center and who is judged to be capable of injecting 
etanercept by himself/herself in the opinion of the investigator/sub-investigator. 
The investigator/sub-investigator should instruct subjects who will self-administer etanercept 
to pay close attention to their condition before and after administration on the day of 
self-administration to assess the condition in a prompt manner. When the 
investigator/sub-investigator finds problems with the subject’s adherence to self-injection 
treatment regimens and the mode of administration, the investigator/sub-investigator will 
administer etanercept at the hospital until the subject can learn to inject it by himself/herself. 
The subject’s condition before and after in-hospital administration should also be closely 
monitored. 
5.1.2 
Previous and Concomitant Medication (Drugs and Therapies) 
The survey period and survey method for previous and concomitant medication (drugs and 
therapies) will be as follows. 
(1) 
Previous medications 
Pharmaceutical name, daily dose, route of administration, period of administration, and 
reason for administration of drugs used within the past 90 days, counting back from before 
the initiation of treatment with the study drug or reference drug on the day of the baseline 
visit 
 DMARD, prohibited concomitant medications, restricted concomitant medications 
(taken within 28 days prior to baseline), rescue medications (taken within 28 days prior 
to baseline) 
Medications for the treatment of RA (biologic DMARD, non-biologic DMARD) should be 
entered separately in the eCRF as the treatment history of the target disease described in 
Section 5.2.3 Diagnosis of the Target Disease, Severity, and Duration of Disease. 

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(2) 
Previous therapies 
None 
(3) 
Concomitant medications 
The survey period will be from the initiation of treatment with the study drug or reference 
drug on the day of the baseline visit. 
Information on pharmaceutical name, daily dose, route of administration, period of 
administration, and reason for administration of DMARD, prohibited concomitant 
medication, restricted concomitant medication, and rescue medication will be collected. 
In addition, pharmaceutical name, route of administration, period of administration, and 
reason for administration of medications other than DMARD, prohibited concomitant 
medication, restricted concomitant medication, rescue medication, and the following will be 
obtained. 
 Solution for dissolving or diluting (water for injection, saline), disinfectant, rinsing fluid, 
surface anesthetic for tests and procedures (such as Xylocaine jelly), contrast media for 
tests (such as barium, noniodinated contrast media), anticoagulants for use by the IV 
placement route, foaming agents and laxatives for use during tests, and topical drugs for 
local effect and for purposes other than RA. 
*However, if such medications are used for the purpose of treating an adverse event, 
they should be entered in the eCRF. 
Medications for the treatment of RA (biologic DMARD, non-biologic DMARD) should be 
entered separately in the eCRF as the treatment history of the target disease described in 
Section 5.2.3 Diagnosis of the Target Disease, Severity, and Duration of Disease. 
(4) 
Concomitant therapies 
The survey period will be from the initiation of study treatment on the day of the baseline 
visit. 
The name, purpose, and duration of therapies performed for RA, and adverse events will be 
obtained. Procedures (such as gauze replacement) and therapies (such as rehabilitation) 
performed for surgery will not be considered as concomitant therapies. 
5.1.2.1 Previous Medication (Drugs and Therapies) 
A period during which a drug cannot be used or a therapy is prohibited will be established as 
follows before the initiation of treatment with the study drug or reference drug for any 
previous medication (drugs and therapies) that could affect the evaluation of ASP015K: 
1) Prohibited concomitant medications and therapies: 
● 
Biologic DMARD 
The following biologic DMARDs will be prohibited during the period shown below: 
 Etanercept: after informed consent is obtained 

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 Anakinra: within 28 days prior to baseline 
 Adalimumab, infliximab: within 56 days prior to baseline 
 Golimumab, certolizumab pegol: within 70 days prior to baseline 
 Abatacept, tocilizumab: within 84 days prior to baseline 
 Denosumab: within 150 days prior to baseline 
 Rituximab: within 180 days prior to baseline 
 
● 
Non-biologic DMARD 
Non-biologic DMARDs other than those listed below will be prohibited within 28 days prior 
to baseline. Subjects who continue receiving the drugs described below during treatment with 
the study drug or reference drug should follow regulations for restricted concomitant 
medications. The use of leflunomide will be prohibited within 180 days prior to baseline. 
However, if washout with cholestyramine for at least 17 days is completed before 28 days 
prior to baseline, the use of leflunomide is prohibited within 28 days prior to baseline. 
However, topical drugs other than those for the treatment of RA may be used concomitantly. 
 Methotrexate (MTX) 
 Hydroxychloroquine 
 Salazosulfapyridine 
 Gold 
 D-penicillamine 
 Lobenzarit 
 Actarit 
 Bucillamine 
 Iguratimod 
 
● 
Other drugs used in the treatment of RA 
Cyclosporine, cyclophosphamide, azathioprine, minocycline, and other drugs indicated for 
the treatment of RA will be prohibited within 28 days prior to baseline. 
● 
Corticosteroids 
Oral corticosteroids at doses exceeding 10 mg per day in the prednisolone equivalent will be 
prohibited within 28 days prior to baseline. 
The intra-articular, intravenous, intramuscular, and endorectal corticosteroid administration 
will also be prohibited within 28 days prior to baseline. However, suppositories for anal 
diseases may be used concomitantly. 
● 
Oral morphine 
Oral morphine at doses exceeding 30 mg per day (or equivalent doses of other opioid 
analgesics) will be prohibited within 28 days prior to baseline. 
● 
Other study drugs 

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Other study drugs will be prohibited within 90 days or 5 half-lives, whichever is longer, prior 
to baseline. 
● 
CYP3A substrates 
The following CYP3A substrates with a narrow therapeutic range will be prohibited within 
14 days prior to baseline: dihydroergotamine, ergotamine, fentanyl, pimozide, quinidine, 
temsirolimus, disopyramide, etc. 
● 
Vaccines 
Live or live attenuated virus vaccinations will be prohibited within 56 days prior to baseline. 
Inactivated vaccines may be administered (influenza, pneumococcal vaccines, etc.). 
● 
Plasma exchange therapy 
Plasma exchange therapy will be prohibited within 60 days prior to baseline. 
● 
Surgical treatment methods 
After obtaining informed consent, surgery involving the target joint will be prohibited. 
● 
Effusion drainage, local anesthesia, and nerve block of the target joint 
Effusion drainage, local anesthesia, and nerve block of the target joint will be prohibited 
within 28 days prior to baseline. 
● 
Articular cartilage protective agents 
The use of articular cartilage protective agents in the target joint will be prohibited within 28 
days prior to baseline. 
2) Restricted concomitant medications 
<Concomitant DMARDs> 
● 
If any (some) of the following DMARDs are administered concomitantly with the study 
drug or reference drug, they should be given for at least 90 days prior to screening, and 
the same dosage and administration schedule must be maintained from at least 28 days 
prior to screening to the end of treatment with the study drug or reference drug. 
● 
Changes to the dosage, administration schedule, or route of administration will not be 
allowed within 28 days prior to baseline and during treatment with the study drug or 
reference drug. 
● 
If a DMARD is temporarily interrupted or its dose is reduced within 28 days prior to the 
baseline visit in a subject eligible at screening for the study based on inclusion and 
exclusion criteria, the screening period will be extended to allow for the same dosage 
and administration schedule to be observed for 28 days prior to the baseline visit. 
● 
If MTX is administered with study drug or reference drug concurrently, the concomitant 
use of folic acid should be considered whenever possible. The dose of folic acid during 
the study period will, in principle, be within 10 mg per week, but it may be adjusted. If 
MTX is administered and ALT/AST becomes ≥ 3 × ULN, MTX must be interrupted, or 
the dose must be reduced, and daily administration of folic acid should be considered. 

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 Methotrexate (MTX) 
 Hydroxychloroquine 
 Salazosulfapyridine 
 Gold 
 D-penicillamine 
 Lobenzarit 
 Actarit 
 Bucillamine 
 Iguratimod 
 
<Other restricted concomitant medications> 
● 
For subjects who continue receiving the drugs described below during treatment with the 
study drug or reference drug, changes to the dosage, administration schedule, or route of 
administration will not be allowed within 28 days prior to baseline. 
● 
The drugs listed below will be prohibited within 28 days prior to baseline if they are to 
be discontinued before the initiation of treatment with the study drug or reference drug 
[except in cases where NSAIDs and non-NSAID analgesics (e.g., acetaminophen, opioid 
analgesics, all-in-one flu and cold medications) are used as rescue medication]. 
● 
In the case of a medically unfavourable event during the screening period, administration 
may be temporarily interrupted, or the dose may be temporarily reduced. The period of 
interruption is up to 28 days. When resuming administration, the dose prior to 
interruption/reduction is the upper limit. 
 NSAIDs (excluding topical drugs) 
 Oral morphine 
(Not more than 30 mg per day, or equivalent doses of other opioid analgesics) 
 Acetaminophen 
 Oral corticosteroids 
(However, at 10 mg per day or less in the prednisolone equivalent and from the visit 
at Week 12, the dose may be reduced or increased within the range not exceeding 
the baseline dose.) 
3) Rescue medications 
The drugs listed below may be used within 28 days prior to baseline only if they are 
necessary for treating a medically unfavourable event or acute worsening of the primary 
disease. However, these medications may not be taken within 24 hours before joint 
assessment at baseline. 
 NSAIDs: For 3 days or less 
 Analgesics other than NSAIDs (acetaminophen, opioid analgesics, all-in-one cold 
and flu medications, etc.): For 7 consecutive days or less. 

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5.1.2.2 Concomitant Medication (Drugs and Therapies) 
1) Prohibited concomitant medications and therapies: 
● 
Biologic DMARDs 
The following biologic DMARDs will be prohibited during treatment with the study drug or 
reference drug. Etanercept given as the reference drug will be excluded. 
Adalimumab, anakinra, infliximab, golimumab, certolizumab pegol, abatacept, 
tocilizumab, rituximab, etanercept, and denosumab 
● 
Non-biologic DMARDs 
Non-biologic DMARDs other than those listed below will be prohibited during treatment 
with the study drug or reference drug.  
Subjects who continue receiving the drugs described below during treatment with the study 
drug or reference drug should follow regulations for restricted concomitant medications. 
Administration of the drugs listed below will be prohibited when subjects do not observe 
these regulations. However, topial drugs other than those for the treatment of RA may be 
used concomitantly. 
 Methotrexate (MTX) 
 Hydroxychloroquine 
 Salazosulfapyridine 
 Gold 
 D-penicillamine 
 Lobenzarit 
 Actarit 
 Bucillamine 
 Iguratimod 
 
● 
Other drugs used in the treatment of RA 
Cyclosporine, cyclophosphamide, azathioprine, minocycline, and other drugs indicated for 
the treatment of RA will be prohibited during treatment with the study drug or reference 
drug. 
● 
Corticosteroids 
Oral corticosteroids at doses exceeding 10 mg per day in the prednisolone equivalent will be 
prohibited during treatment with the study drug or reference drug. 
The intra-articular, intravenous, intramuscular, and endorectal corticosteroid administration 
will also be prohibited during treatment with the study drug or reference drug. However, 
suppositories for anal disease may be used concomitantly. 

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● 
Oral morphine 
Oral morphine at doses exceeding 30 mg per day (or equivalent doses of other opioid 
analgesics) will be prohibited during treatment with the study drug or reference drug. 
● 
Other study drugs 
Other study drugs will be prohibited during treatment with the study drug or reference drug 
and during the follow-up period. 
● 
CYP3A substrates 
The following CYP3A substrates with a narrow therapeutic range will be prohibited during 
treatment with the study drug or reference drug and during the follow-up period: 
dihydroergotamine, ergotamine, fentanyl, pimozide, quinidine, temsirolimus, disopyramide, 
etc. 
● 
Vaccines 
Live or live attenuated virus vaccinations will be prohibited during treatment with the study 
drug or reference drug and during the follow-up period. Inactivated vaccines may be 
administered (influenza, pneumococcal vaccines, etc.) 
● 
Plasma exchange therapy 
Plasma exchange therapy will be prohibited during treatment with the study drug or reference 
drug. 
● 
Surgical treatment methods 
Surgery involving the target joint will be prohibited during treatment with the study drug or 
reference drug. 
● 
Effusion drainage, local anesthesia, and nerve block of the target joint 
Effusion drainage, local anesthesia, and nerve block of the target joint will be prohibited 
during treatment with the study drug or reference drug. 
● 
Articular cartilage protective agents 
The use of articular cartilage protective agents in the target joint will be prohibited during 
treatment with the study drug or reference drug. 
2) Restricted concomitant medications 
<Concomitant DMARDs> 
● 
If any (some) of the following DMARDs are administered concomitantly with the study 
drug or reference drug, they should be given for at least 90 days prior to screening, and 
the same dosage and administration schedule must be maintained from at least 28 days 
prior to screening to the end of treatment with the study drug or reference drug. 
● 
Changes to the dosage, administration schedule, or route of administration will not be 
allowed during treatment with the study drug or reference drug. 

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● 
In the case of AEs, administration may be temporarily interrupted, or the dose may be 
temporarily reduced. When resuming administration, the baseline dose is the upper limit. 
The period of interruption is up to 28 days and interruption is allowed only once. 
● 
If MTX is administered with study drug or reference drug concurrently, the concomitant 
use of folic acid should be considered whenever possible. The dose of folic acid during 
the study period will, in principle, be within 10 mg per week, but it may be adjusted. If 
MTX is administered and ALT/AST becomes ≥ 3 × ULN, MTX must be interrupted, or 
the dose must be reduced, and daily administration of folic acid should be considered. 
 
 Methotrexate (MTX) 
 Hydroxychloroquine 
 Salazosulfapyridine 
 Gold 
 D-penicillamine 
 Lobenzarit 
 Actarit 
 Bucillamine 
 Iguratimod 
 
<Other restricted concomitant medications> 
For subjects who continue receiving the drugs described below during treatment with the 
study drug or reference drug, changes to the dosage, administration schedule, or route of 
administration will not be allowed from 28 days prior to baseline to the end of treatment with 
the study drug or reference drug, except when the following conditions are satisfied: 
● 
The drugs listed below will be prohibited from 28 days prior to baseline to the end of 
treatment with the study drug if they are discontinued before the initiation of treatment 
with the study drug or reference drug [except in cases where NSAIDs and non-NSAID 
analgesics (e.g., acetaminophen, opioid analgesics, all-in-one flu and cold medications) 
are used as rescue medication]. 
● 
In the case of AEs, administration may be temporarily interrupted, or the dose may be 
temporarily reduced. The period of interruption is up to 28 days. When resuming 
administration, the baseline dose is the upper limit. 
● 
From the visit at Week 12, the drugs below may be discontinued, new drugs may be used, 
and the dosage, administration schedule, or route of administration of the concomitant 
drugs may be changed. However, with the exception of oral corticosteroids, after 
changing the conditions, administration must be continued under the same conditions for 
12 weeks or longer. 
 NSAIDs (excluding topical drugs) 
 Oral morphine 
(Not more than 30 mg per day, or equivalent doses of other opioid analgesics) 
 Acetaminophen 

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 Oral corticosteroids 
(However, at 10 mg per day or less in the prednisolone equivalent and from the visit 
at Week 12, the dose may be reduced or increased within the range not exceeding 
the baseline dose.) 
3) Rescue medications 
The drugs listed below may be used only if they are necessary for treating AEs, comorbid 
conditions, or acute aggravation of the primary disease during the administration period of 
the study drug or reference drug. However, these medications may not be taken within 24 
hours before joint assessment at each visit. 
 NSAIDs: For 3 days or less 
 Analgesics other than NSAIDs (acetaminophen, opioid analgesics, all-in-one flu and 
cold medications, etc.): For 7 consecutive days or less 
5.1.3 
Treatment Compliance 
The investigator, sub-investigator, or study drug storage manager will provide the subjects 
with an explanation of how to take the study drug or inject the reference drug, paying 
particular attention to the following points when they hand the study drug or reference drug 
to each subject. 
● 
Do not take multiple doses all at once if doses of the study drug have been missed. 
● 
Bring any remaining study drug with you to the next scheduled examination. 
● 
Immediately contact the investigator, sub-investigator, or collaborator if there is a 
shortage of the study drug before the next visit due to the loss of study drugs, etc. 
● 
When you have been assigned to the reference group and are given an injection on an 
outpatient basis, visit the study site every week for etanercept injection. Record the date 
and site of injection in source documents. 
● 
When you have been assigned to the reference group and inject etanercept by yourself, 
record the date and site of injection in the medication diary. Closely monitor your health, 
particularly on the date of injection, and immediately contact the investigator, 
sub-investigator, or collaborator if something is wrong with your health. Bring any 
unused syringes with you to the next scheduled visit. In principle, bring used syringes 
and needles with you to the next scheduled visit. 
● 
Be sure to avoid an overdose if you have been assigned to the reference group and inject 
etanercept by yourself. 
● 
If you forget to inject etanercept by yourself, bring unused syringes with you to the next 
scheduled visit. 
The investigator/sub-investigator will confirm each subject’s compliance with study and 
reference treatment and the injection of the reference drug during treatment with the study 
drug or reference drug on the basis of information given by the subject and the number of 
tablets (study drugs) or syringes (reference drugs) collected from the subject, and the 
investigator/sub-investigator will record the number of tablets or syringes prescribed and the 
number of unused tablets or syringes in the eCRF. If there is judged to be a problem with the 

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rate of compliance or injection, guidance on patient compliance should be provided to the 
subject again to improve the rate of compliance or the method of injection after investigating 
the reasons for the problem. 
In addition, each subject should be asked regarding the most recent day on which the study 
drug was taken and the time at which it was taken, at each scheduled visit at Weeks 4, 8, 12, 
28, and 52, and at discontinuation, and information should be recorded in the eCRF. It is not 
necessary to collect information regarding the time of reference drug injection from subjects 
in the reference group. 
5.1.4 
Emergency Procedures and Management of Overdose 
If any symptoms have developed as a result of an overdose of ASP015K or etanercept, the 
investigator/sub-investigator will provide emergency treatment appropriate for each symptom 
under full monitoring to ensure the safety of the subject. 
Experience with administration of ASP015K to humans remains limited, and overdose of 
ASP015K has not been reported. However, based on data on AEs from previous studies, the 
first sign of overdose of ASP015K may be nausea, diarrhoea, other GI symptoms, CPK 
increased, lymphocytes decreased, or neutropenia. 
The following information regarding an overdose of etanercept is available in its package 
insert: 
The maximum tolerated dose of etanercept has not been established in humans. Single IV 
doses up to 60 mg/m2 have been administered to healthy volunteers in an endotoxemia study 
without evidence of dose-limiting toxicities. The highest dose level evaluated in RA patients 
has been a single IV loading dose of 32 mg/m2 followed by SC doses of 16 mg/m2 (up to 
25 mg/m2) administered twice weekly. There is no known antidote to etanercept. 
5.1.5 
Criteria for Continuation of Treatment 
Subjects in the ASP015K 100 mg, ASP015K 150 mg, or placebo groups who completed the 
assessment at study visit at Week 52 may participate in an extension study (015K-CL-RAJ2) 
if they wish to do so. Subjects in the reference group will not be eligible for participation in 
the open-label extension study. Each subject must provide informed consent for the extension 
study before completing the assessment at study visit at Week 52. 
5.1.6 
Compliance Rules to be Observed by Subjects throughout the Study 
The investigator, sub-investigator, or collaborator will explain the following to the subjects 
during the study period. 
 In principle, subjects should visit the study center for the study visit on the specified date. 
The visits may be adjusted within an allowable range, but the visit dates must be adjusted 
so that the intervals between the specified visits are 5 weeks at most. 
 The subject should visit the study center on the day of each study visit without taking the 
dose of the study drug for that day prior to the visit. The subject in the reference group 
should also visit the study center on the day of each scheduled study visit without 

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injecting etanercept if he/she has an injection on that visit day. The subject must also fast 
for at least 8 hours prior to the blood sampling at the time of the study visit. If a subject 
must make an unscheduled visit due to adverse events, etc., on the day of taking the 
study drug, the unscheduled visit will be prioritized regardless of whether the study drug 
was taken and the timing of meals. 
 If a new treatment (starting to take a new drug or use a new therapy, etc.) has been 
prescribed by another department or another medical institution during the study period, 
the subject should contact the investigator/sub-investigator before starting to use the new 
treatment, and follow the instructions given by the investigator/sub-investigator. If it is 
not possible to contact the investigator/sub-investigator in advance, the subject should 
contact one of them, or the collaborator, as soon as possible. 
 Any subject who wishes to take prescription medication or over-the-counter drugs 
unconfirmed by the investigator/sub-investigator should confirm with the investigator, 
sub-investigator, or collaborator in advance whether to take the drug. If it is not possible 
to contact the investigator/sub-investigator in advance, the subject should contact one of 
them, or the collaborator, as soon as possible. 
 Subjects must practice contraception through 2 or more appropriate contraceptive 
methods throughout the study period, and for 90 days after the end of treatment with the 
study drug or reference drug in the case of male subjects and for 60 days after the end of 
treatment with the study drug or reference drug in the case of female subjects of 
childbearing potential. 
 Female subjects must not breastfeed throughout the study period and for 60 days after 
the end of treatment with the study drug or reference drug. 
 If another visit is instructed by the investigator/sub-investigator due, for example, to a 
laboratory finding subject to CPK monitoring and liver function monitoring, the subject 
must promptly visit the study center. 
 
5.2 
Demographics and Baseline Characteristics 
5.2.1 
Demographics 
The date of obtaining informed consent, date of birth, sex, and study region will be recorded 
in the eCRF. In addition, height, history of smoking, and alcohol consumption habits will be 
confirmed during the screening test period and recorded in the eCRF. 
5.2.2 
Medical History 
Diseases cured before the initiation of treatment with the study drug or reference drug will be 
regarded as previous diseases, and diseases that remain uncured at the initiation of treatment 
with the study drug or reference drug will be regarded as concurrent diseases. All concurrent 
diseases will be investigated, and the name of the diagnosis will be recorded in the medical 
record or other source documents, as well as in the eCRF. Serious infectious diseases (in the 

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past 365 days from baseline) and herpes zoster are subjects to investigation, and the history, 
name of diagnosis, date of onset, and date of recovery will be entered in the eCRF. 
5.2.3 
Diagnosis of the Target Disease, Severity, and Duration of Disease 
Information on following items will be obtained and entered in the eCRF: 
● 
Name of diagnosis, onset date of RA, and criteria for the classification of RA used for 
the diagnosis (Appendix 5, Appendix 6) 
● 
ACR 1991 revised criteria for the classification of global functional status in RA 
(Appendix 7) at screening 
● 
Classification of disease stage/progression of RA (Appendix 8) at screening 
● 
History of surgery for RA (name of surgery, joint operated, possibility of joint 
assessment) 
● 
Names of RA treatment drugs used in the past (DMARD), treatment response, and 
tolerability 
● 
Names of DMARDs to which subjects are considered to have an inadequate response for 
this study, doses of DMARDs before 90 days prior to the initiation of screening, timing 
for the initiation of DMARDs for the treatment of RA, treatment response, and 
tolerability 
 
5.3 
Efficacy, Pharmacodynamics, and Pharmacokinetics Assessments 
5.3.1 
Efficacy Assessments 
5.3.1.1 Tender and Swollen Joint Counts 
(1) 
Tender joint count 
The investigator/sub-investigator will examine the subject for tender joints, assessing 
the 68 joints listed below, and confirm the location of each tender joint. The 28 joints 
subject to assessment will also be examined for tender joints and the location will be 
confirmed. The number of respective confirmed joints and the date of assessment will 
be entered in the eCRF. 
(2) 
Swollen joint count 
The investigator/sub-investigator will examine the subject for swollen joints, assessing 
the 66 joints listed below, with the exception of the hip joints, and confirm the location 
of the swollen joints. The 28 joints subject to assessment will also be examined for 
swollen joints and the location will be confirmed. The number of respective confirmed 
joints and the date of assessment will be entered in the eCRF. 
 

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Table Joints Subject to Assessment 
Temporomandibular joints (2), sternoclavicular joints (2), acromioclavicular joints (2), 
shoulder joints (2)*, elbow joints (2)*, wrist joints (2)*, DIP joints (8), PIP joints of both 
hands (10)*, MCP joints (10)*, hip joints (2), knee joints (2)*, ankle joints (2), tarsal bones 
(2), MTP joints (10), interphalangeal joint joints of toes (2), PIP joints of both feet (8) 
*: Joints subject to DAS28 assessment 
5.3.1.2 Assessment of Pain and Overall Assessment of Disease Activity 
The following assessments will be performed on the scheduled assessment days from the 
baseline: 
(1) 
Subject’s assessment of pain: The subject assesses his/her own pain severity on a VAS 
of 0–100 mm on the questionnaire form. The measured value and the date of 
assessment will be entered in the eCRF. 
(2) 
SGA: The subject assesses his/her own disease activity on a VAS of 0–100 mm on the 
questionnaire form. The measured value and the date of assessment will be entered in 
the eCRF. 
(3) 
PGA: The investigator/sub-investigator assesses the subject’s disease activity on a VAS 
of 0–100 mm on the physician assessment table. The measured value and the date of 
assessment will be entered in the eCRF. 
5.3.1.3 Acute Phase Reactants (CRP and ESR) 
Only CRP is measured during the screening test period. Blood sampling is performed on the 
scheduled assessment days from baseline to measure CRP and ESR. The measurement of 
CRP will be performed by the central laboratory, and the measurement of ESR will be 
performed by each study center. These results will be used to calculate DAS28, SDAI, and 
ACR response criteria assessment. One-hour value of ESR will be measured. The measured 
ESR and the date of measurement will be entered in the eCRF. 
5.3.1.4 EULAR Response Criteria 
Based on DAS28 scores and changes in DAS28 scores before and after treatment with the 
study drug or reference drug, EULAR Response Criteria categorize response to treatment as 
“No response,” “Moderate response,” or “Good response” according to the definition given 
in the table below [van Gestel et al, 1996; van Gestel et al, 1998]. 

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Table Definition of EULAR Response Criteria Assessment 
DAS28 after treatment 
DAS28 response (DAS28 before treatment - DAS28 after treatment) 
> 1.2 
> 0.6 and ≤ 1.2 
≤ 0.6 
≤ 3.2 
Good response 
Moderate response 
No response 
> 3.2 and ≤ 5.1 
Moderate response 
Moderate response 
No response 
> 5.1 
Moderate response 
No response 
No response 
5.3.1.5 DAS28 
The subject’s DAS28 will be calculated at the screening visit and on each subsequent 
assessment day using data from the following assessments, together with the formula shown 
below [Prevoo et al, 1995; van der Heijde et al, 1990; Fransen et al, 2003; Mallya et al, 1982; 
Wolfe, 1997]. 
● 
TJC (28 joints) 
● 
SJC (28 joints) 
● 
CRP or ESR 
● 
SGA 
[When CRP is used] 
DAS28 = 0.56√(TJC) + 0.28√(SJC) + 0.36 ln (CRP + 1) + 0.014 × SGA + 0.96 
 
[When ESR is used] 
DAS28 = 0.56√(TJC) + 0.28√(SJC) + 0.70 ln ESR + 0.014 × SGA 
DAS28 score is assessed as below. 
• 
High disease activity: DAS28 score of > 5.1 
• 
Moderate disease activity: DAS28 score of > 3.2 and ≤ 5.1 
• 
Low disease activity: DAS28 score of ≤ 3.2 
If the DAS28 score is less than 2.6, the subject will be considered to be in DAS28 remission 
[van Gestel et al, 1998; Fransen and van Riel, 2005]. 
5.3.1.6 SDAI Score 
The SDAI score at baseline and Week 12 will be calculated using data from the following 
assessments, together with formula shown below [Smolen et al, 2003; Aletaha and Smolen, 
2005; Felson et al, 2011]. 
● 
TJC (28 joints) 
● 
SJC (28 joints) 
● 
SGA 
● 
PGA 
● 
CRP (mg/dL) 
SDAI = TJC + SJC + SGA + PGA + CRP 
The SDAI score is assessed as below. 
• 
High disease activity: SDAI score exceeding 26 
• 
Moderate disease activity: SDAI score exceeding 11 and not greater than 26 

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• 
Low disease activity: SDAI score exceeding 3.3 and not greater than 11 
If the SDAI score is 3.3 or less, the subject will be considered to be in SDAI remission. 
5.3.1.7 ACR Response Criteria Assessment 
ACR Response Criteria [Felson et al, 1995] measure improvement in TJC, SJC, subject’s 
assessment of pain, SGA, PGA, assessment of physical function using HAQ-DI, and acute 
phase reactant (CRP or ESR). 
The ACR20 response requires that all criteria from (1) to (3) below be met. The ACR50 
response indicates a 50% improvement in all criteria from (1) to (3) below, and the ACR70 
response similarly indicates a 70% improvement. In this study, [5] is assessed with CRP. 
(1) 
TJC: ≥ 20% reduction compared with baseline 
(2) 
SJC: ≥ 20% reduction compared with baseline 
(3) 
≥ 20% improvement in 3 or more of the following 5 parameters compared with 
baseline 
[1] Subject’s assessment of pain 
[2] SGA 
[3] PGA 
[4] Disability Index (HAQ-DI) 
[5] CRP or ESR 
5.3.1.8 Patient Reported Outcomes/Assessments 
Subjects will complete the following assessments at baseline and on days specified in the 
Schedule of Assessments. The outcome of the assessments will be recorded in the eCRF. In 
principle, the copy of assessment forms will be provided to the sponsor. 
● 
HAQ-DI [Fries et al, 1982; Ramey et al, 1992] 
● 
SF-36v2® [Ware, 2004] 
● 
WPAI [Takeuchi T, 2011; Reilly MC, 1993] 
5.3.2 
Pharmacodynamic Assessments 
Blood samples will be collected at baseline and on days specified in the Schedule of 
Assessments. At the study visit points where blood sample collection for PK assessment is 
performed, sample collection for PD assessment will be performed before treatment with the 
study drug or reference drug and at the same time as that for the sampling for PK assessment. 
These measurements will be performed at the central laboratory, and the results will be 
reported to the sponsor and the study center after the breaking of the treatment code. 
5.3.2.1 Lymphocyte Subsets 
Lymphocyte subset quantification of CD3, CD4, CD8, CD16, CD19, CD56, and CD56/16 
will be performed, and the changes from baseline will be calculated. The date of blood 
sampling will be entered in the eCRF. 

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5.3.2.2 Biomarkers for Efficacy and Safety Assessments 
To assess the effects of ASP015K on biomarkers, VEGF and MMP-3 will be measured, and 
the changes from baseline will be calculated. The date of blood sampling will be entered in 
the eCRF. 
Additional analysis may be performed for biomarkers for efficacy and safety assessments 
based on study results using blood samples that have been collected during the study and 
biobanked (i.e., residual sample stored for retrospective analysis). These could include 
biomarkers of inflammation, bone or cartilage metabolism, or inhibitory activity of JAK, but 
other biomarkers may also be subject to analysis. 
5.3.3 
Pharmacokinetic Assessments 
The concentration of ASP015K will be measured. If necessary, the concentrations of 
ASP015K metabolites will also be measured. Subjects in the reference group will be 
excluded from concentration measurement and will not provide blood samples. Blood 
samples will be collected at baseline and on the days specified in the Schedule of 
Assessments. Moreover, the date and time on which the last dose of study drug will be taken 
just prior to blood sampling will be recorded in the eCRF, together with the date and time of 
blood sampling. 
The sampling for the assessment of post-dose concentrations will be performed as a substudy 
at study centers approved for the sampling. The sampling for the assessment of post-dose 
concentrations will be performed at either Week 4 or Week 8, 2 hours after the administration 
of the study drug (the acceptable time range is from 1 hour to 4 hours post-dose). In addition, 
the sampling for post-dose concentrations will be performed on the same day as central ECG 
at Week 4 or Week 8, promptly after the central ECG. 
 
5.4 
Safety Assessment 
The following tests and observations will be made for the purpose of safety assessments at 
baseline and on the days specified in the Schedule of Assessments. The requirements for 
reporting and analysis of information on drug-induced liver injury (DILI) are in Appendix 4 
“Liver Safety Monitoring and Assessment.” If marked liver function abnormal in Appendix 4 
is observed, the investigator or the responsible personnel should contact the sponsor or CRO 
by telephone or fax (within 24 hours of awareness). 
5.4.1 
Vital Signs 
Blood pressure (in the sitting position), pulse rate, and body temperature at rest will be 
measured at screening and on the days specified in the Schedule of Assessments. The date of 
measuring and measurements taken (blood pressure and the measuring position, systolic 
blood pressure, diastolic blood pressure, pulse rate, and body temperature) will be entered in 
the eCRF. 

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5.4.2 
Body Weight 
Body weight will be measured at screening and on the days specified in the Schedule of 
Assessments. The date of measuring and measurements taken will be entered in the eCRF. 
5.4.3 
Adverse Events 
The survey period for AEs will be from the initiation of treatment with the study drug or 
reference drug to before the initiation of administration in the extension study or until the end 
of follow-up. 
Events that occurred after treatment with the study drug or reference drug until before the 
initiation of administration in the extension study or until the end of follow-up will be 
recorded as AEs. Concurrent diseases that worsened during the study will also be recorded as 
AEs. AEs that occurred after the subject has completed the study plan or has been discharged 
from the hospital or the study center will not be recorded. 
AEs that have not resolved before the initiation of administration in the extension study or at 
the end of follow-up must be followed-up until resolved or judged to be no longer clinically 
significant or until they become chronic to the extent that they can be fully characterized. If 
the event resolves during the study period, the date of resolution is to be entered in the eCRF. 
See Appendix 4 “Liver Safety Monitoring and Assessment” for the assessment of AEs 
caused by DILI. 
Herpes zoster should be entered as an AE information in the eCRF, and also, a separate 
Herpes Zoster (shingles) Worksheet should be prepared, and a copy should be submitted to 
the sponsor. If the sponsor considers necessary and requests for submission of forms for the 
purpose of providing additional information on other AEs, a form must be prepared to report 
to the sponsor. 
5.4.3.1 Adverse Events of Possible Hepatic Origin 
Subjects with liver-derived AEs associated with hepatic function abnormal should be 
monitored carefully. 
5.4.4 
Laboratory Assessments 
The below hematology, biochemistry, fasting lipid profile, and urinalysis will be performed 
at screening and on each of the days specified in the Schedule of Assessments. These 
measurements will be performed at the central laboratory. For the period of performing 
additional laboratory tests for DILI, see Appendix 4 “Liver Safety Monitoring and 
Assessment.” 
Additional sampling and tests may be performed if it is considered necessary by the 
investigator/sub-investigator or if retesting is considered necessary by the 
investigator/sub-investigator because the results could not be obtained due to defects in the 
sample. Additional tests and analysis may be performed based on the study results using 
blood samples for laboratory assessments that have been collected during the study and have 
been biobanked (i.e., residual samples stored for retrospective analyses). 

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1) Hematology, biochemistry (including fasting lipid profile tests), urinalysis 
The following hematology, biochemistry, fasting lipid profile tests, and urinalysis will be 
performed: 
● 
Hematology 
Hemoglobin, hematocrit, erythrocytes (RBC), leukocytes (WBC), differential WBC 
(neutrophils, lymphocytes, monocytes, eosinophils, basophils), platelet count 
Each blood cell count will be calculated from the differential WBC. 
● 
Biochemistry 
Na, K, Ca, Cl, Mg, HCO3, BUN, phosphorus, glucose, creatinine, ALP, AST (GOT), 
ALT (GPT), γ-GTP, total bilirubin, total protein, albumin, uric acid, CPK, LDH, serum 
amylase, eGFR, β-D-glucan 
● 
Fasting lipid profile 
Total cholesterol, LDL, HDL, triglycerides 
The date of sample collection will be entered in the eCRF. 
 Blood specimens for scheduled fasting lipid profile tests should be drawn after the 
subject has fasted for at least 8 hours, unless it is at termination or at an unscheduled 
visit when the subject could not fast. 
● 
Urinalysis 
pH, specific gravity, protein (qualitative), glucose (qualitative), keton bodies 
(qualitative), bilirubin (qualitative), occult blood, sediment 
2) Pregnancy test (for females only) 
Pregnancy testing will be performed from screening according to the Schedule of 
Assessments. Serum pregnancy testing is required only at screening, and urine 
pregnancy testing will be performed after baseline. The serum pregnancy testing will be 
performed by the central laboratory and the urine pregnancy testing will be performed by 
the study centers using the kits provided by the central laboratory. If, in the serum 
pregnancy test, hCG level exceeds ULN, but the possibility of pregnancy can be 
completely ruled out by another test, the subject is eligible for enrollment. Pregnancy 
testing is not subject to the safety assessment. 
 If a urine pregnancy test is positive at any time, a negative serum pregnancy is 
required for the subject to continue participation in the study. If the possibility of 
pregnancy can be completely ruled out by another test, the subject may continue to 
participate in the study. 
 The pregnancy tests need not be performed if the possibility of pregnancy can 
clearly be ruled out, such as if the woman is postmenopausal and has not had a 
menstrual period for 1 year or more, or has had a hysterectomy, bilateral 
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3) Tuberculosis test 
The tuberculosis test will be performed at screening to confirm the eligibility of the 
subject in accordance with Exclusion Criterion 14. T-SPOT or QuantiFERON Gold test is 
the preferential test for tuberculosis infection. If T-SPOT or QuantiFERON Gold test 
cannot be performed, tuberculin skin test may be performed instead. Tuberculin test and 
QuantiFERON Gold test cannot be performed at the central laboratory in Japan. 
Tuberculin test and T-SPOT cannot be performed at the central laboratory in Korea and 
Taiwan. Tuberculosis test is not required at screening provided that there is 
documentation of a negative tuberculosis test within 90 days prior to baseline. 
4) Hepatitis test 
Tests for HBs antigens, HBs antibodies, the HBV-DNA assay, HBc antibodies, and 
HCV antibodies will be performed at the screening visit to confirm the eligibility of the 
subject. If a subject is positive for either or both HBc antibodies and HBs antibodies, the 
subject will be monitored during treatment with the study drug or reference drug by 
performing an HBV-DNA assay at scheduled visits and early termination. Safety 
analysis will not be performed for the results of HBV-DNA assays from baseline. 
5) CPK monitoring 
If an increase in CPK is observed, in accordance with Section 5.4.4.1 CPK Monitoring, 
when CPK is retested, CPK, CK-MB, troponin T, and aldolase should also be tested. 
Urinalysis (blood and microscopy) will be performed as part of the targeted physical 
examination. 
5.4.4.1 CPK Monitoring 
If a CPK elevation is observed after treatment with the study drug or reference drug is 
initiated, CPK will be monitored as follows: 
● 
If laboratory testing reveals CPK > 3 × ULN, and the subject is asymptomatic, retest 
CPK preferably within 1 week of previous blood sampling to confirm it. Subsequently, 
retest CPK weekly (from the date of the initial CPK elevation) until CPK is ≤ 3 × ULN 
or is stable according to the judgment of the investigator/sub-investigator. If the retest 
cannot be performed within 1 week of blood sampling, which marks the starting point of 
CPK monitoring, suspension or interruption of the study drug or reference drug should 
be considered until the retest results are obtained. 
● 
In subjects whose baseline CPK is already > 3 × ULN, if laboratory testing reveals CPK 
> 2 × baseline, and the subject is asymptomatic, retest CPK preferably within 1 week of 
previous blood sampling to confirm it. Subsequently, retest CPK weekly (from the date 
of CPK elevation to > 2 × baseline) until CPK is ≤ 2 × baseline, or is stable in the 
judgment of the investigator/sub-investigator. If the retest cannot be performed within 1 
week of blood sampling, which marks the starting point of CPK monitoring, suspension 
or interruption of the study drug or reference drug should be considered until the retest 
results are obtained. 

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● 
If CPK is > 10 × ULN at any time, treatment with the study drug or reference drug will 
be immediately suspended or interrupted (see Section 3.4 Discontinuation Criteria for 
Individual Subjects), and retest CPK. 
● 
If there is a symptomatic CPK elevation (CPK elevation > 1.5 × ULN accompanied by 
severe and unusual episodes of myalgia, muscular weakness, or muscle twitching), as 
reported by the investigator/sub-investigator, treatment with the study drug or reference 
drug will be immediately discontinued (see Section 3.4 Discontinuation Criteria for 
Individual Subjects).  
In the retest for CPK monitoring, the following tests will be performed in addition to CPK 
measurements. The content of the subject questionnaire will be entered in the eCRF. 
 Laboratory tests 
(Measurement parameters: CK-MB, troponin T, aldolase) 
 A targeted physical examination* and subject questionnaire to assess muscle strength 
and pain 
*: As part of the targeted physical examination, urinalysis (blood and microscopy) will 
be performed. 
5.4.4.2 Hepatic Function Abnormal 
If laboratory testing for a subject enrolled in the study and receiving the study drug or 
reference drug reveals an increase in serum aminotransferase (ALT, AST) > 3 × ULN or 
TBL > 2 × ULN, at least 4 parameters (ALT, AST, ALP, and TBL) of the usual hepatic 
function test parameters should be retested. The retest should be performed between 48 hours 
and 72 hours after notification of the test results. 
For additional information on monitoring and the assessment of the hepatic function test, see 
Appendix 4 “Liver Safety Monitoring and Assessment.” 
If laboratory testing for a subject enrolled in the study receiving the study drug or reference 
drug reveals an increase in serum aminotransferase (ALT, AST) > 3 × ULN and TBL > 2 × 
ULN, the investigator will determine whether it is an SAE. Even if the abnormality is not 
considered an SAE by the investigator/sub-investigator, it will be reported to the sponsor or 
CRO in writing as in the case of SAEs. 
5.4.5 
Physical Examination 
A physical examination will be performed at scheduled visits and early termination to 
confirm physical findings. 
Physical findings and RA symptoms will be confirmed at unscheduled visits whenever 
possible. 
5.4.6 
12-lead Electrocardiogram (ECG) 
A 12-lead ECG will be obtained at screening and on the assessment dates specified in the 
Schedule of Assessments. The investigator/sub-investigator will confirm the ECG chart, 
assess the results as “normal,” “abnormal but not to a clinically important degree,” or 

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“clinically important abnormality,” and record the results of the assessment in the CRF. If the 
finding is “abnormal but not to a clinically important degree” or “clinically important 
abnormality,” the finding will be recorded in the CRF. 
The screening 12-lead ECG must be performed within 4 weeks prior to the first dose of study 
drug or reference drug. In addition, the clinical interpretation of the results of this 
examination must be completed prior to the first dose of study drug or reference drug. 
5.4.7 
Radiography 
Chest radiography will be performed at screening and on the assessment dates specified in 
the Schedule of Assessments. Chest radiography examination will be performed at early 
termination if it is determined necessary by the investigator/sub-investigator. However, chest 
radiography at screening is not required provided that there is documentation of a normal 
chest radiograph within 90 days from baseline. The investigator/sub-investigator will confirm 
the chest radiographic images, assess the results as “normal,” “abnormal but not to a 
clinically important degree,” or “clinically important abnormality,” and the 
investigator/sub-investigator record the results of the assessment in the eCRF. 
If the results of chest radiography at screening reveal findings of tuberculosis, the subject’s 
eligibility will be decided in accordance with Exclusion Criterion 14. 
5.4.8 
Central ECG 
Central ECG is conducted as sub-study at the sites which approved blood sampling for 
post-dose drug concentration. Subjects in the reference group will be excluded from Central 
ECG. Central ECG is performed at baseline before study drug administration, as well as 
before study drug administration and 2 hours after study drug administration at Week 4 or 
Week 8 on the same day as blood sampling for post-dose drug concentration at Week 4 or 
Week 8. 12-lead ECG is performed as Central ECG. The measurement date and time of 
central ECG is recorded in the eCRF. 
The measuring and transmittal method of central ECG in the handling manual provided by 
sponsor is followed. The QT interval, QTcF and QTcB will be calculated by the third party 
using the Central ECG data transmitted and the method of ECG analysis is described in the 
handling manual prepared by the third party. 
5.5 
Adverse Events and Other Safety Aspects 
5.5.1 
Definition of Adverse Events (AEs) 
An AE is defined as any untoward medical occurrence in a subject administered a study drug 
or reference drug that does not necessarily have a causal relationship with this treatment. An 
AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory 
finding), symptom, or disease temporally associated with the use of a study drug or reference 
drug, whether or not related to the study drug or reference drug. 
 

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An abnormality identified during a medical test (e.g., laboratory parameter, vital sign, ECG 
data, physical examination) should be defined as an AE only if the abnormality meets one of 
the following criteria: 
● 
Induces clinical signs or symptoms 
● 
Requires active intervention 
● 
Requires suspension, interruption, or discontinuation of the study drug or reference drug 
● 
The abnormality or laboratory test value is clinically significant based on the opinion of 
the investigator or other responsible personnel 
The particulars to be noted with respect to the AE are the name of the event, date of onset, 
date of disappearance, severity (at peak time), seriousness, treatment of the study drug or 
reference drug, other treatment, outcome, causal relationship to the study drug or reference 
drug, and rationale for the assessment of causal relationship. The rationale for the assessment 
of the causal relationship does not need to be recorded for all AEs but only at the request of 
the sponsor. The severity of each event should be recorded on a scale of Grade 1 to Grade 5 
in the eCRF, and the causal relationship to the study drug should be recorded as “Probable,” 
“Possible,” or “Not related” (see Section 5.5.3 Criteria for Causal Relationship to the Study 
Drug and Section 5.5.4 Criteria for Defining the Severity of an Adverse Event). The 
treatment of the AE (whether it was treated with pharmacotherapy or by other means) and the 
treatment of the study drug or reference drug should be recorded in the medical record or 
other source documents and in the eCRF. The outcome should be recorded in the medical 
record or other source documents and in the eCRF as “resolved,” “alleviated,” “unresolved,” 
“resolved but with late effects,” “death,” or “unknown.” 
5.5.2 
Definition of Serious Adverse Events (SAEs) 
An adverse event is considered “serious” if, in the view of either the investigator or Sponsor, 
it results in any of the following outcomes: 
● 
Results in death 
● 
Is life threatening (an adverse event is considered “life-threatening” if, in the view of 
either the investigator or Sponsor, its occurrence places the subject at immediate risk of 
death. It does not include an adverse event that, had it occurred in a more severe form, 
might have caused death) 
● 
Results in persistent or significant disability/incapacity or substantial disruption of the 
ability to conduct normal life functions 
● 
Results in congenital anomaly, or birth defect 
● 
Requires inpatient hospitalization or leads to prolongation of hospitalization 
(hospitalization for treatment/observation/examination caused by AE is to be considered 
as serious) 
● 
Other medically important events 
Medical and scientific judgment should be exercised in deciding whether expedited reporting 
is appropriate in other situations, such as important medical events that may not be 
immediately life-threatening or result in death or hospitalization but may jeopardize the 

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subject or may require intervention to prevent one of the other outcomes listed in the 
definition above. These events, including those that may result in disability/incapacity, 
should also usually be considered serious. Examples of such events are intensive treatment in 
an emergency room or at home for allergic bronchospasm; blood dyscrasias or convulsions 
that do not result in hospitalization; or development of drug dependency or drug abuse. 
In addition, all sponsor’s clinical studies have the requirement that all the medical events 
described in Appendix 3 “Events Always considered to be Serious” and Appendix 4 “Liver 
Safety Monitoring and Assessment” be reported by the investigator as SAEs even if they do 
not meet the aforementioned conditions. 
5.5.3 
Criteria for Causal Relationship to the Study Drug 
AEs that fall under either “Possible” or “Probable” should be defined as “AEs whose 
relationship to the study drug could not be ruled out.” This definition also applies to those 
occurring in the reference group. 
Causal Relationship 
to Study Drug 
Related Assessment Criteria 
Not related 
A clinical event, including laboratory test abnormality, with a temporal 
relationship to drug administration which makes a causal relationship 
improbable, and/or in which other drugs or underlying disease provide 
plausible explanations. 
Possible 
A clinical event with a reasonable time sequence to administration of the 
drug, to which one of the following applies: 
• Could also be explained by concurrent/underlying disease or other drugs 
• Information on drug withdrawal is lacking or unclear 
Probable 
A clinical event with a reasonable time sequence to administration of the 
drug, to which one of the following applies: 
• Recurs upon re-administration of the drug, or disappears or is alleviated 
when the drug is withdrawn. 
• Cannot be explained by concurrent/underlying disease or other drugs or 
is unlikely to be attributable to them 
5.5.4 
Criteria for Defining the Severity of an Adverse Event 
The AE grades will be based on NCI-CTCAE [Japan Clinical Oncology Group (JCOG), 
2011]. Items unspecified by these criteria will be assessed according to the following criteria 
and recorded. 

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Grade 
Assessment Criteria 
Grade 1 (Mild) 
Mild; asymptomatic or mild symptoms; clinical or diagnostic 
observations only; intervention not indicated. 
Grade 2 (Moderate) 
Moderate; minimal, local or noninvasive intervention indicated; 
limiting age-appropriate instrumental ADL. 
Grade 3 (Severe) 
Severe or medically significant but not immediately life-threatening; 
hospitalization or prolongation of hospitalization indicated; 
disabling; limiting self care ADL. 
Grade 4 (Life-threatening or 
incapacitating) 
Life-threatening consequences; urgent intervention indicated. 
Grade 5 (Death) 
Death related to AE. 
5.5.5 
Reporting of Serious Adverse Events (SAEs) 
In the case of a serious adverse event (SAE), the investigator must contact the Sponsor/ 
delegated CRO by telephone or fax immediately (within 24 hours of awareness) [in case of 
Japan: in addition to reporting to the head of the study center]. 
The investigator should complete and submit an SAE report containing all information that is 
required by the Regulatory Authorities to the Sponsor/delegated CRO [in case of Japan: and 
to the head of the study center] by fax immediately (within 24 hours of awareness). If the 
faxing of an SAE report is not possible or is not possible within 24 hours, the investigator 
should inform the Sponsor or delegated CRO by phone. 
SAEs occurring in the reference group should also be reported in the same way as above. 
For contact details, see Section II CONTACT DETAILS OF KEY SPONSOR’S 
PERSONNEL.  
Please fax the SAE report to: 
Contact Information of the Sponsor 
 
TEL: 
, FAX: 
 
Contact Information of CRO 
Japan: 
 
TEL: 
  
FAX: 
 
Korea: 
 
TEL: 
, FAX: 
 
Taiwan: 
 

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TEL: 
, FAX: 
 
5.5.6 
Follow-up of Adverse Events 
All AEs occurring during or after the subject has discontinued the study are to be followed up 
until resolved or judged to be no longer clinically significant, or until they become chronic to the 
extent that they can be fully characterized.  
If during AE follow-up, the adverse event progresses to an "SAE", or if a subject experiences 
a new SAE, the investigator must immediately report the information to the Sponsor/ 
delegated CRO.  
Even if the subject does not return to normal or to his/her previous state, follow-up can be 
considered no longer necessary or finished when the following procedures have been taken: 
[1] Follow-up is considered no longer necessary if: 
The investigator/sub-investigator judges that follow-up of the subject is no longer necessary 
because the AE’s relationship to the study drug or reference drug could be ruled out, and this 
judgment is considered appropriate by the sponsor. 
[2] Follow-up is considered finished if: 
The investigator judges that follow-up of the subject is no longer necessary based on the 
progression made during follow-up; the reason for such a judgment is entered as a comment 
in the CRF for follow-up, and the sponsor judges that the reason is acceptable with regard to 
the safety of the subject concerned. 
 
For details of follow-up of DILI (medical history, concomitant medications, history of 
alcohol intake and narcotic use), see Appendix 4 “Liver Safety Monitoring and Assessment.” 
5.5.7 
Procedure in Case of Pregnancy 
If a woman is proven to be pregnant during treatment with the study drug or reference drug 
or within 28 days from the end of treatment or early termination, the investigator should 
report this information to the sponsor/CRO in the same manner as that for an SAE. The 
expected date of delivery, last menstruation, estimated fertility date, pregnancy result and 
neonatal data etc., should be included in this information. 
The investigator or other responsible personnel will handle the pregnancy in the same manner 
as an SAE and will follow the medical status of the mother, as well as the fetus, and report 
the outcome to the sponsor. 
When the outcome of the pregnancy falls under the criteria for SAEs [spontaneous abortion, 
induced abortion, stillbirth, death of newborn, congenital anomaly (including anomaly in a 
miscarried fetus)] and when information on newborn falls under the criteria for SAEs 
(including death, congenital anomaly, and other anomalies), the investigator should respond 
in accordance with the report procedure for SAEs. 

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Additional information regarding the outcome of a pregnancy (which is categorized as an 
SAE) is mentioned below. 
“Spontaneous abortion” includes abortion and missed abortion. 
Death of a newborn within 1 month after birth should be reported as an SAE regardless of its 
relationship with the study drug. 
If a newborn dies more than 1 month after the birth, it should be reported if a relationship 
between the death and intrauterine exposure to the study drug is judged as “possible” by the 
investigator or other responsible personnel. 
In the case of a delivery of a living newborn, the “normality” of the newborn is evaluated at 
the birth. 
“Normality” of the miscarried fetus is evaluated by visual examination unless test results 
which indicate a congenital anomaly are obtained prior to miscarriage. 
If a male subject impregnates his partner during the conduct of the clinical study, the subject 
should report the pregnancy to the investigator or other responsible personnel, and the 
investigator must report the pregnancy to the sponsor/CRO. 
5.5.8 
Supply of New Information Affecting the Conduct of the Study 
In Japan: 
1. When information is obtained regarding serious and unexpected adverse drug reactions 
(or other) that are specified in Article 80-2 Paragraph 6 and Article 273 of the Law for 
Ensuring the Quality, Efficacy, and Safety of Drugs and Medical Devices, the Sponsor 
should inform all the investigators involved in the clinical study, the head of the study 
site, and the regulatory authorities of such information. The head of the study site who 
receives such information will decide whether the clinical study should be continued 
after hearing the opinions of the IRB. The investigator will supply the new information 
to the subjects, in compliance with Section 8.2.3.3 Supply of New and Important 
Information Influencing the Subject’s Consent and Revision of the Written Information. 
2. In addition to the above item 1, when the head of the study site receives the revisions of 
the Investigator’s Brochure, protocol, or written information, information on the matters 
covering the quality of the study drug, efficacy and safety, information necessary for 
conducting the clinical study properly, or documents to be examined by the IRB should 
be sent to the IRB. 
3. According to the Pharmaceutical and Medical Device Safety Information Reporting 
System, information regarding serious and unexpected adverse drug reactions and others 
occurring in the reference group will be reported to the regulatory authorities or 
marketing authorization holders. The sponsor will not report serious and unexpected 
adverse drug reactions and others that occurred in the reference group because the 
marketing authorization holder provides such information to medical institutions through 
revisions to the package inserts. 
 
In Korea and Taiwan: 

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When the sponsor gains new information suggesting adverse impact on the subjects’ safety, 
safe conduct of the clinical study, or the IRB/IEC approval for study continuation, the 
sponsor will immediately notify all investigators, all study sites, and relevant regulatory 
authorities. 
The sponsor must immediately report SAEs to all participating principal investigators, study 
sites (and the IRBs/IECs if appropriate) in compliance with local requirements and the 
relevant regulatory authorities. 
When information necessary for conducting the clinical study properly (including “Dear 
Doctor Letters” but not limited to that) becomes available and leads to a protocol amendment, 
the sponsor should inform the regulatory authorities, as well as all investigators and medical 
institutions involved in the clinical study, who will then inform the IRB/IEC of such 
information, and when needed, should amend the Written Information. 
5.5.9 
Deviations from the Protocol and Other Actions Taken to Avoid 
Life-Threatening Risks to Subjects 
The investigator must not deviate from or amend the protocol without prior written consent 
of sponsor and prior written approval from IRB/IEC.  
In Japan: 
When the investigator does not follow the protocol in order to avoid urgent risks for subjects, 
the investigator should take the following actions.  
1. Describe the contents of the deviation or amendment and the reasons for it in a written 
notice, and immediately send the document stating the deviation or amendment and the 
reasons to the Sponsor and the head of the study site. Keep a copy of the notice. 
2. Consult with the Sponsor at the earliest possibility for cases in which it is necessary to 
amend the protocol. Obtain approval for a draft of the amended protocol from the IRB 
and the head of the study site as well as written approval from the Sponsor. 
In Korea and Taiwan: 
When the investigator does not follow the protocol in order to avoid urgent risks for subjects, 
the investigator should report to sponsor, IRB/IEC, and regulatory authority (if applicable) in 
compliance with local requirements. 
5.6 
Test Drug Concentration 
The plasma concentrations of ASP015K will be measured in the samples collected at the time 
points in Table 1 Schedule of Assessments, except the reference group. The concentrations of 
ASP015K metabolites H1, H2, and H4 will also be measured if necessary. 
In the placebo group, the concentrations of samples collected during the period of the 
administration of placebo will not be measured, but the concentration of samples collected 
after switching to ASP015K 100 mg or ASP015K 150 mg will be measured. The 
concentration of the sample collected on the day of the visit for switching will be measured 
as baseline.  

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The subject registration center will provide information on study drug assignment to the 
institution performing measurements of drug concentrations. The institution performing 
measurements of drug concentrations will measure the drug concentrations of samples of 
subjects in the placebo group who switched to ASP015K 100 mg or ASP015K 150 mg. 
Concentration measurements will be performed by central laboratory using a validated, 
established LC-MS/MS method [Test No.: 
(ASP015K, H2), 
 (H4), 
 (H1)]. The lower limit of quantification is 0.25 ng/mL. Blood samples for drug 
concentration (2 mL/sample) will be collected into a 2 mL vacutainer tube containing 
ethylenediamine-tetra-acetic acid (K3EDTA-3K). See the written explanation of testing 
procedure enclosed in the clinical laboratory testing kit for descriptions of the procedure for 
sampling blood and storing and shipping the blood samples. The central laboratory will not 
report the results of determinations to the investigator, sub-investigator, sponsor, or other 
third parties until the breaking of the treatment code. 
 
5.7 
Other Measurements, Assessments, or Methods 
5.7.1 
Pharmacodynamic Measurements 
In this study, the following will be measured as part of the pharmacodynamic evaluation: 
biomarkers of bone or cartilage metabolism and lymphocyte subsets (see Section 5.3.2.2 
Biomarkers for Efficacy and Safety Assessments). 
Blood samples for biomarkers of bone or cartilage metabolism will be collected in a 2 mL 
sampling tube containing EDTA-2Na, and samples for lymphocyte subsets will be collected 
in a 2 mL vacutainer tube containing EDTA-2K in Japan, and in a 3 mL vacutainer tube 
containing EDTA-2K in Korea and Taiwan. See the written explanation of testing procedure 
enclosed in the clinical laboratory testing kit for descriptions of the procedure for sampling 
blood and storing and shipping the blood samples. 
The central laboratory will not report the results to the investigator, sub-investigator, sponsor, 
or other third parties until the breaking of the treatment code. 
5.7.2 
Purposes of Pharmacogenomics 
● 
Pharmacogenomics will only be performed at study centers in Japan and Korea that have 
approved to the content of the research, and only those study centers will follow the 
procedures described in Sections 5.7, 8.2, and 8.3. 
● 
To prepare for future research that will analyze the relationship between genes and the 
efficacy, safety, or pharmacokinetics of the test drug, blood samples will be collected 
and stored. 
● 
To prepare for future research that will analyze the relationship between genome and the 
efficacy or safety of the test drug, biological samples will be stored over long-term. 
Details will be described in the “Bio-Banking Procedures” prepared separately. 
● 
To prepare for future exploratory research on biomarkers that can predict the 
pharmacologic response [efficacy and toxicity (adverse drug reactions)] through the 

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analysis of genetic information from this study or from integration of other studies using 
this test drug, biological samples will be collected and stored. 
● 
If a serious adverse drug reaction is observed, samples for genomic/genetic analysis will 
be collected to explore the markers related to the adverse drug reaction. 
5.7.3 
Handling and Storage for Samples Used for Pharmacogenomics 
To prepare for future research that will analyze the relationship between genes and the 
efficacy, safety, or pharmacokinetics of the study drug, blood samples will be collected and 
stored after obtaining consent from the subject to participate in PGx research and after 
randomization of blood samples and, whenever possible, before the first dose of the study 
drug. If it is not possible to take the sample before the first dose, it should be taken by the end 
of the study. The subject’s consent to participate in the PGx research must be obtained after 
the subject has given consent to participate in the main study and by the time the blood 
sample for bio-banking is taken. 
At study centers in Japan and Korea approved to conduct PGx research, blood samples will 
be taken from those subjects participating in the main study who have given written consent 
for the collection and storage of blood samples for use in PGx research. On one occasion 
during the study period, the investigator, sub-investigator, or collaborator will collect 5 mL 
of peripheral blood from a forearm vein(s) in a storage tube and store it at the study center at 
4ºC until the time of specimen collection. The date on which informed consent was obtained 
and the sampling date should be recorded for each subject and entered into the eCRF. The 
sample collection and shipping agency should then temporarily store the blood sample for 
PGx research (at −20ºC or −80ºC) and send it to the prolonged storage laboratory for samples 
used in PGx research. The prolonged storage laboratory for samples used in PGx research 
will collect the blood samples and store them at −80ºC until it is time to analyze them. All 
collected PGx samples will be maintained for a period of up to 15 years after database hard 
lock. 
● 
Sample anonymization: Because the specific content of the analyses to be performed in 
the PGx research has not yet been determined, the specimens will be double coded and 
anonymized. After the first code (subject identification code) has been assigned by the 
study center, the second code will be assigned by the prolonged storage laboratory for 
samples used in PGx research. 
5.7.4 
Disposal of Pharmacogenomics Samples 
At the conclusion of the retention period, or if the prolonged storage laboratory for samples 
used in PGx research has been notified by the investigator to the effect that the subject has 
withdrawn consent for PGx research or that the sponsor has decided to dispose of the stored 
samples, the prolonged storage laboratory for samples used in PGx research should promptly 
remove the labels from the tubes holding the subject’s samples and dispose of the samples as 
appropriate. If genome/gene analysis has been performed before the end of the storage period 
or before consent is withdrawn, the data obtained through that analysis will not be destroyed. 

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5.7.5 
Disclosure of Genetic Information 
Even if PGx research is conducted in the future, the research will be exploratory, and since 
any results obtained from the gene analyses (results of gene assays, relationship between 
genes and drug response) are expected to be lacking in accuracy and definitiveness, the 
results of the gene analysis will not be disclosed. 
5.8 
Total Amount of Blood 
The approximate total volume of blood required for tests performed at the central laboratory 
during the study period is as follows. Blood sampling for the assessment of plasma drug 
concentrations (trough and post-dose concentrations) will not be performed for the reference 
group. 
Additionally, there will be 16 samplings for ESR at the study center, and the amount will 
differ between the centers (approximately 1 mL to 2 mL per sampling). The amount of blood 
required for T-SPOT and Quantiferon Gold test (tuberculosis test) to be performed at the 
central laboratory is 10 mL and 3 mL respectively. 
Subjects who are positive for hepatitis and continuing the study will require a HBV-DNA 
assay at baseline and each subsequent visit after initiation of study drug or reference drug 
administration, and the amount of blood required is 5 mL in Japan and Taiwan, and 8.5 mL 
in Korea per assay respectively. 
Moreover, if blood samples are required at unscheduled visits or follow-up, the amount will 
increase. If CK-MB, troponin T, and aldolase are measured as part of CPK monitoring, the 
amount of blood required is 4 mL in Japan, and 5 mL in Korea and Taiwan per assessment 
respectively. 

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Assessment 
Screening 
Baseline 
Week 4 
Week 8 
Week 12 
Weeks 16, 
20, 24, 28, 
32, 36, 40, 
44, 48 
Week 52 or 
at early 
termination 
Follow- 
up 
Volume of 
sample 
(mL) 
Hematology, 
biochemistry 
(including CRP, 
fasting lipid 
profile test) 
JP:16 
KR:18.5 
TW:16.5 
JP:16 
KR:18.5 
TW:16.5 
JP:16 
KR:18.5 
TW:16.5 
JP:16 
KR:18.5 
TW:16.5 
JP:16 
KR:18.5 
TW:16.5 
JP:144 
(16 × 9) 
KR:166.5 
(18.5 × 9) 
TW:148.5 
(16.5 × 9) 
JP:16 
KR:18.5 
TW:16.5 
JP:16 
KR:18.5 
TW:16.5 
JP:256 
KR:296 
TW:264 
Hepatitis test 
JP:6 
KR:3.5 
TW:5 
0 
0 
0 
0 
0 
0 
0 
JP:6 
KR:3.5 
TW:5 
Hepatitis DNA 
testing*3 
JP:5 
KR:8.5 
TW:5 
0 
0 
0 
0 
0 
0 
0 
JP:5 
KR:8.5 
TW:5 
Trough 
concentration*1 
0 
2 
2 
2 
2 
2 
(Week 28 
only) 
2 
0 
12 
PD sampling 
0 
JP:4 
KR:8.5 
TW:8.5 
JP:4 
KR:8.5 
TW:8.5 
JP:4 
KR:8.5 
TW:8.5 
JP:4 
KR:8.5 
TW:8.5 
JP:4 
KR:8.5 
TW:8.5 
(Week 28 
only) 
JP:4 
KR:8.5 
TW:8.5 
JP:4 
KR:8.5 
TW:8.5 
JP:28 
KR:59.5 
TW:59.5 
PGx*1 
0 
5 
0 
0 
0 
0 
0 
0 
5 
Post-dose 
concentration 
(if performed)*1 
 
 
2 
 
 
 
 
2 
Total 
JP:27 
KR:30.5 
TW:26.5 
JP:27 
KR:34 
TW:27 
JP:24*2 
KR:31 
TW:29 
JP:22 
KR:29 
TW:27 
JP:22 
KR:29 
TW:27 
JP:150 
KR:177 
TW:159 
JP:22 
KR:29 
TW:27 
JP:20 
KR:27 
TW:25 
JP:314*4 
KR:386.5 
TW:347.5 
*1: No blood sampling will be performed for the reference group and the subject in Taiwan. 
*2: For convenience, the sampling for the assessment of post-dose concentration is summarized at Week 4. 
*3: For subjects who are positive for HBs antibody/HBc antibody and require a hepatitis DNA assay at baseline and each 
subsequent visit, the amount of blood required is 5 mL in Japan and Taiwan, and 8.5 mL in Korea per assay. 
*4: In case of reference group, the total blood volume to be collected is 295 mL in Japan, 367 mL in Korea, and 333.5 mL in 
Taiwan. 

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6 
TERMINATION OF THE CLINICAL STUDY 
1. When the sponsor is aware of information on matters concerning the quality, efficacy, 
and safety of the study drugs, as well as other important information that may affect 
proper conduct of the clinical study, the sponsor may discontinue the clinical study and 
send a written notice of the discontinuation along with the reasons to the investigator 
[unique to Japan: and the head of the study center]. 
2. If the investigator wishes to discontinue the study in the particular study center while the 
study is still in progress, the investigator should contact the sponsor [unique to Japan: 
and the head of the study center] immediately to inform them of the discontinuation and 
the reason for it. 
 

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7 
STATISTICAL METHODOLOGY 
A detailed elaboration of the statistical analysis will be included in a separate statistical 
analysis plan and PK analysis plan based on the opinions and advice from a medical expert 
and/or statistical advisor. After review, it will be finalized prior to unblinding. 
7.1 
Sample Size 
One hundred subjects per group will receive the study drug and 200 subjects the reference 
drug (a total of 500 subjects). 
[Rationale for the sample size] 
Based on 015K-CL-RAJ1 result and efficacy result from other RA drugs [XELJANZ®, tablet, 
5 mg, CTD (2013)] [CIMZIA, sc, 200 mg, Syringe, CTD (2012)], 62 subjects per group will 
provide 90% power to detect a difference assumed in the Step 2 in the closed testing 
procedure (described in Section 7.4.1.1 Primary Analysis) under the following assumptions. 
In addition, it is assumed that ACR20 response rate of each country (Japan, Korea and 
Taiwan) is similar. 
● 
ACR20 response rate at Week 12 in the placebo group: 25% 
● 
ACR20 response rate at Week 12 in the ASP015K 100 mg group: 54.5% 
● 
ACR20 response rate at Week 12 in the ASP015K 150 mg group: 65.5% 
● 
Two-sided significance level of 0.05 
On the other hand, according to the Extent of Population Exposure to Assess Clinical Safety 
for Drugs Intended for Long-term Treatment of Non-life-threatening Conditions (PAB/PCD 
Notification No.592, dated 24 May 1995), (“the long-term treatment guideline”), a sample 
size of 300-600 subjects under long-term treatment (6 months) is adequate to observe delayed 
adverse events at a reasonable frequency (generally, 0.5% to 5%) and to observe whether 
there is an increase in high-frequency adverse events during the later stage of treatment. For 
treatment lasting 1 year, 100 subjects is acceptable. It is also described in “Guidelines on 
methodology for clinical assessment of antirheumatic drugs” (PFSB/ELD Notification No. 
0217001, dated 17 February 2006) that 100 subjects for 1 year are necessary.  
Therefore, to collect data for 300 subjects for 6 month period, and for 100 subjects for 1 year 
period in both ASP015K 100 mg and 150 mg groups among 015K-CL-RAJ2/RAJ3/RAJ4 
studies as long-term treatment data, approximately 80 subjects per treatment group (400 
subjects in total) as a target are necessary to be enrolled in Japan. In addition, the target 
sample size for Taiwan is set at 10 subjects per treatment group (50 subjects in total) as a 
target in consideration of the requirement of regulatory authority in Taiwan (10% or more 
Taiwan subjects) and target sample size for Korea is also set at 10 subjects per treatment 
group (50 subjects in total) as a target. Therefore, the target sample size per treatment group 
is set at 100 subjects in total for 3 regions. 
[Rationale for the sample size for the reference group] 

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The target sample size for the reference group was set at 200 subjects, considering the 
followings: 
o 
Incidence rates for serious infections from post marketing studies for approved biologic 
drugs: approximately 1.0% to 3.6% reported in post-marketing all-case surveillance 
[ACTEMRA®, drip infusion, 80 mg, 200 mg, 400 mg, final reports for all patients ] 
[ORENCIA®, drip infusion, 250 mg, information for appropriate drug usage] 
[HYUMIRA®, sc, 40 mg, Syringe 0.8 mL, information for appropriate drug usage]; and 
approximately 2.4% in the 5 mg group and approximately 1.5% in the Adalimumab 
group, as revealed by pooled analysis of the phase III tofacitinib study [XELJANZ®, 
tablet, 5 mg, CTD (2013)] 
o 
Operational feasibility 
Setting the sample size of reference group as 200, it can be detectable at least 1 subject with 
95% confidence probability for AE which occurs at 1.5% incidence rate. 
 
7.2 
Analysis Set 
The study analyses will be performed on the following analysis sets. Final judgments on 
inclusion/exclusion of subjects from the analyses will be made at the Case Review based on 
the opinions and advice from a medical expert and/or statistical advisor. 
7.2.1 
Full Analysis Set (FAS) 
FAS will consist of all subjects who are randomized and receive at least 1 dose of the study 
drug or reference drug. This will be the primary data set for efficacy analyses. 
7.2.2 
Per Protocol Set (PPS) 
PPS includes all subjects of FAS who meet the following criteria. PPS is defined based on 
the data up to Week 12. 
• 
Have no violation of inclusion criteria; 
• 
Do not meet any exclusion criteria possibly interfering with the efficacy evaluation; 
• 
Receive study or reference treatment for 8 weeks (56 days) or longer from the 
initiation of treatment to Week 12* (those who have discontinued the study drug or 
reference drug due to the lack of efficacy should be included in PPS); 
• 
Have study or reference treatment compliance of 75% or higher for 12 weeks after 
treatment; 
• 
Have evaluable primary efficacy variables; and 
• 
Have no major protocol violations after registration. 
Subjects who are considered to have no impact on the efficacy evaluation at the Case Review 
Meeting will also be included in PPS, if they are not satisfying these criteria. 
*: The duration of treatment with the study drug will be calculated by subtracting the first 
day of study drug treatment from the date of treatment completion plus 1 day, and the 

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duration of treatment with the reference drug will be calculated by subtracting the first day of 
reference drug treatment from the date of treatment completion plus 8 days. 
7.2.3 
Safety Analysis Set (SAF) 
SAF is defined as all subjects who received at least 1 dose of the study drug or reference 
drug. 
7.2.4 
Pharmacokinetic Analysis Set (PKAS) 
PKAS will consist of all subjects who receive at least 1 dose of the study drug and who 
provide samples for drug concentrations for at least 1 time point. 
7.2.5 
Pharmacodynamics Analysis Set (PDAS) 
All subjects who receive at least 1 dose of the study drug or 1 injection of the reference drug 
and who provide samples for the determination of pharmacodynamic parameters at least 1 
time point will be included in PDAS. 
 
7.3 
Demographics and Other Baseline Characteristics 
Demographics and other baseline characteristics will be summarized by treatment group 
(ASP015K 100 mg, ASP015K 150 mg, placebo, reference groups) for SAF. Descriptive 
statistics will include sample size, mean, standard deviation, minimum, median and 
maximum for continuous variables, and frequency and percentage for categorical variables. 
To detect a possible treatment imbalance among treatment groups, chi-squared test will be 
used to analyze categorical variables and one-way analysis of variance (ANOVA) will be 
used to analyze continuous variables. The significance level is set at 0.05. 
 
7.4 
Analysis of Efficacy 
Efficacy analysis will be conducted on FAS and PPS. The interpretation of results from 
statistical tests will be based on FAS. In the primary analysis of the primary variable, the 
purpose of using PPS is to assess the robustness of the results from the statistical tests based 
on FAS. Primary efficacy variable analysis will be performed for the ASP015K 100 mg, 
ASP015K 150 mg, and placebo groups, and only summary statistics will be calculated for the 
reference group. Unless otherwise noted, analysis will performed for the treatment groups at 
allocation (ASP015K 100 mg, ASP015K 150 mg, placebo, reference groups) and, if 
necessary, for the treatment groups taking into consideration a switch from placebo to active 
treatment (ASP015K 100 mg, ASP015K 150 mg, placebo–ASP015K 100 mg, placebo–
ASP015K 150 mg, reference groups). 
7.4.1 
Analysis of Primary Variable 
7.4.1.1 Primary Analysis 
Primary analysis will be conducted on FAS. For the ACR20 response at Week 12/ET, 
pairwise comparisons to placebo will be performed at each ASP015K dose level using 

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logistic regression model with treatment group (Placebo, ASP015K 100 mg, and ASP015K 
150 mg) as the factor and the prior biologic-DMARD-IR, concomitant DMARD use, and 
study region (Japan, Korea, and Taiwan) as the covariates. For multiplicity adjustment, 
following closed testing procedure will be done. 
Step 1. ACR20 response at Week 12/ET: ASP015K 150 mg vs. Placebo 
Step 2. ACR20 response at Week 12/ET: ASP015K 100 mg vs. Placebo 
The null hypotheses will be tested at a two-sided significance level of 0.05. 
For the missing data imputation of ACR20 at Week 12/ET, Last Observation Carried 
Forward (LOCF) methodology will be used. 
7.4.1.2 Secondary Analysis 
The same analysis of the primary variable as described in Section 7.4.1.1 will be conducted 
using PPS. A sensitivity analysis will be conducted to impute the missing data. In addition 
the same analysis as the primary analysis will be conducted for Japanese subjects. 
Furthermore, a re-randomization test by the Monte Carlo sampling method will be performed 
as a sensitivity analysis to evaluate the appropriateness of the results of the dynamic 
allocation. 
7.4.1.3 Subgroup Analysis 
Subgroup analyses for sex, age categories, prior biologic-DMARD-IR, concomitant DMARD 
use during the treatment period with the study drug or reference drug, study region, and 
others may be explored. 
7.4.2 
Analysis of Secondary Variables 
For secondary efficacy endpoints, binary variables such as Percentage of subjects achieving 
ACR50 response at Week 12/ET, and Percentage of subjects achieving ACR70 response at 
Week 12/ET will be analyzed (to Week 12/ET) using logistic regression model as described 
in the primary analysis with treatment group as the factor and the prior biologic-DMARD-IR, 
concomitant DMARD use during the study period and study region (Japan, Korea and 
Taiwan) as the covariates. Continuous variables, such as Change from baseline/Day 1 to 
Week 12/ET in DAS28-CRP and DAS28-ESR scores, will be analyzed using analysis of 
covariance (ANCOVA) with treatment group as the factor, and the prior 
biologic-DMARD-IR, concomitant DMARD use, study region (Japan, Korea, and Taiwan), 
and baseline value as the covariates. Each ASP015K group will be compared with placebo 
group (to Week 12/ET) and multiplicity for the secondary efficacy variables will not be 
adjusted. 
 
7.5 
Analysis of Safety 
The following analyses will be performed on SAF. Unless otherwise noted, analysis will 
performed for the treatment groups at allocation (ASP015K 100 mg, ASP015K 150 mg, 
placebo, reference groups) and, if necessary, for the treatment groups after placebo was 

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switched to active treatment (ASP015K 100 mg, ASP015K 150 mg, placebo–ASP015K 
100 mg, placebo–ASP015K 150 mg, reference groups). In addition, analysis will be 
performed for each study region (Japan, Korea, and Taiwan). 
7.5.1 
Adverse Events 
AEs will be coded using the Medical Dictionary for Regulatory Activities (MedDRA/J). The 
incidence of AEs, SAEs, AEs leading to discontinuation, and AEs whose relationship to 
study drugs or reference drugs could not be ruled out will be summarized by system organ 
class and preferred term, as well as the treatment group. The incidence of AEs by severity 
will also be summarized. 
7.5.2 
Laboratory Assessments 
Descriptive statistics will be used to summarize clinical laboratory measurements and the 
change from baseline if quantitative, by time point. 
7.5.3 
Vital Signs 
Descriptive statistics will be used to summarize vital sign measurements and the change from 
baseline by time point. 
7.5.4 
12-lead ECG 
The frequency of each category of 12-lead ECG results will be summarized by time point. 
7.5.5 
QT assessment 
Descriptive statistics will be used to summarize QT assessment (including QTc assessment) 
measurements and the change from baseline. 
The frequency of each category of QT assessment (including QTc assessment) will be 
summarized by time point. 
In addition, the relationship between quantity of QT change and concentration of ASP015K 
may be explored. 
7.5.6 
Body Weight 
Descriptive statistics will be used to summarize measurements by time point. 
 
7.6 
Analysis of Pharmacokinetics 
A detailed elaboration of the PK analysis will be included in a separate PK analysis plan. The 
trough plasma concentrations of ASP015K will be summarized by treatment group and visit. 
In addition, the same PK analysis will be conducted for each study region (Japan, Korea, and 
Taiwan). Exploratory population PK analysis may be performed by pooling the results 
obtained so far. 
 

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7.7 
Other Analyses 
7.7.1 
Analysis of Pharmacodynamics 
Analysis will be performed in PDAS. Descriptive statistics will be used to summarize PD 
measurements and the change from baseline by time point. 
7.7.2 
Analysis of Pharmacogenomics 
At present, the content of analysis as part of pharmacogenomic research has not been 
determined yet. The relationship between the results from genetic analyses and study data 
(clinical information such as pharmacological activity, toxicity and PK) may be explored in 
the future. The sponsor can initiate such research once a specific methodology is established. 
Prior to research, the sponsor will prepare a research plan (including procedures and timing 
of document disposal) and have appropriateness of conduct of the research reviewed and 
approved by the sponsor's ethics review committee from ethical and scientific viewpoints. 
 
7.8 
Interim Analysis (and Early Discontinuation of the Clinical Study) 
Not applicable. Review of safety data and safety evaluation will be completed by an 
independent DSMB [see Section 10.1 Independent Data and Safety Monitoring Board 
(DSMB)] during the study in accordance with separate SOP. 
 
7.9 
Handling of Missing Data, Outliers, Visit Windows, and Other 
Information 
Final judgments on handling of missing data, outliers, visit windows, and other information 
will be made at the Case Review Meeting based on the opinions and advice from a medical 
expert and/or statistical advisor prior to treatment code breaking and included in the SAP. 
The acceptable time ranges for the efficacy and safety examinations and observations from 
the date of initial study or reference treatment (Day 1) are defined as follows. If there are 
multiple data available over the same period of time, the data obtained on the date closest to 
the reference date will be utilized; the later date will be applied if the number of days from 
the reference date is equal. Subjects who have no evaluable post-dose data on ACR20, 
ACR50, and ACR70 response rates after initial treatment with the study drug or reference 
drug will be counted as non-responders and included in the analysis at the end of Week 12 
(Week 12 or at early termination before Week 12). 
7.9.1 
Handling of Schedule of Assessments of Efficacy Variables 
For data after the end of study treatment, data obtained within + 2 days after the last dose is 
taken will be included in analysis. For data after the end of reference treatment, data obtained 
within + 9 days after the last dose will be included in analysis. 

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(1) 
TJC (68 joints)/SJC (66 joints), laboratory test (CRP) 
Time points defined in analysis 
Reference date* 
Acceptable time range 
Screening 
Day −28 to Day −1 
Day −28 to Day −1 
Baseline 
Day 1 
Day 1 
Week 4 to Week 48** 
Day 7×x + 1 
Day (7×x − 6) to Day (7×x + 8) and 
before the initiation of treatment with the 
study drug or reference drug on the visit day 
Week 52 
Day 365 
Day 358 to Day 372 
End of Week 12 (Week 12 or at 
early termination before Week 12) 
Day 85 
Day 2 to Day 92 
End of treatment (Week 52 or at 
early termination) 
Day 365 
Day 2 to Day 372 
*: Day 1 represents the first day of study or reference treatment. The day before the initiation of treatment with the study 
drug or reference drug is expressed as Day −1. 
**: Represents the reference date and acceptable time range for Week x. 
(2) 
PGA and SGA (VAS), subject’s assessment of pain (VAS), HAQ-DI, laboratory test 
(ESR) 
Time points defined in analysis 
Reference date* 
Acceptable time range 
Baseline 
Day 1 
Day 1 
Week 4 to Week 48** 
Day 7×x + 1 
Day (7×x − 6) to Day (7×x + 8) and 
before the initiation of treatment with the 
study drug or reference drug on the visit day 
Week 52 
Day 365 
Day 358 to Day 372 
End of Week 12 (Week 12 or at 
early termination before Week 12) 
Day 85 
Day 2 to Day 92 
End of treatment (Week 52 or at 
early termination)  
Day 365 
Day 2 to Day 372 
*:  Day 1 represents the first day of study or reference treatment. The day before the initiation of treatment with the study 
drug or reference drug is expressed as Day −1. 
**: Represents the reference date and acceptable time range for Week x. 
(3) 
SF-36 v2®, WPAI 
Time points defined in analysis 
Reference date* 
Acceptable time range 
Baseline 
Day 1 
Day 1 
Week 4 to Week 28** 
Day 7×x + 1 
Day (7×x − 6) to Day (7×x + 8) and 
before the initiation of treatment with the 
study drug or reference drug on the visit day 
Week 52 
Day 365 
Day 358 to Day 372 
End of Week 12 (Week 12 or at 
early termination before Week 12) 
Day 85 
Day 2 to Day 92 
End of treatment (Week 52 or at 
early termination) 
Day 365 
Day 2 to Day 372 
*:  Day 1 represents the first day of study or reference treatment. The day before the initiation of treatment with the study 
drug or reference drug is expressed as Day −1. 
**: Represents the reference date and acceptable time range for Week x. 
7.9.2 
Handling of Schedule of Assessments of Safety Variables 
For data obtained after the end of study treatment, the data obtained within + 2 days after the 
last dose is taken will be included in analysis. For data after the end of reference treatment, 
data obtained within + 9 days after the last dose will be included in analysis. 

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(1) 
Physical examination, vital signs, laboratory test [hematology, biochemistry, urinalysis, 
and pregnancy test (serum and urine)] 
Time points defined in analysis 
Reference date* 
Acceptable time range 
Screening 
Day −28 to Day −1 
Day −28 to Day −1 
Baseline 
Day 1 
Day 1 
Week 4 to Week 48** 
Day 7×x + 1 
Day (7×x − 6) to Day (7×x + 8) and 
before the initiation of treatment with the 
study drug or reference drug on the visit day 
Week 52 
Day 365 
Day 358 to Day 372 
End of Week 12 (Week 12 or at 
early termination before Week 12) 
Day 85 
Day 2 to Day 92 
End of treatment (Week 52 or at 
early termination) 
Day 365 
Day 2 to Day 372 
*:  Day 1 represents the first day of study or reference treatment. The day before the initiation of treatment with the study 
drug or reference drug is expressed as Day −1. 
**: Represents the reference date and acceptable time range for Week x. 
(2) 
Laboratory test (fasting lipid profile test) 
Time points defined in analysis 
Reference date* 
Acceptable time range 
Baseline 
Day 1 
Before the initiation of treatment with the 
study drug or reference drug on Day 1 and 
at least 8 hours after the last meal 
Week 12 
Day 85 
Day 78 to Day 92 
Week 28 
Day 197 
Day 190 to Day 204 
Week 40 
Day 281 
Day 274 to Day 288 
Week 52 
Day 365 
Day 358 to Day 372 
End of Week 12 (Week 12 or at 
early termination before Week 12) 
Day 85 
Day 2 to Day 92 
End of treatment (Week 52 or at 
early termination) 
Day 365 
Day 2 to Day 372 
*: Day 1 represents the first day of study or reference treatment. The day before the initiation of treatment with the study 
drug or reference drug is expressed as Day −1. 
(3) 
12-lead ECG 
Time points defined in analysis 
Reference date* 
Acceptable time range 
Screening 
Day −28 to Day −1 
Day −28 to Day −1 
Week 28 
Day 197 
Day 190 to Day 204 
Week 52 
Day 365 
Day 358 to Day 372 
End of treatment (Week 52 or at 
early termination) 
Day 365 
Day 2 to Day 372 
*:  Day 1 represents the first day of study or reference treatment. The day before the initiation of treatment with the study 
drug or reference drug is expressed as Day −1. 

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(4) 
Body weight 
Time points defined in analysis 
Reference date* 
Acceptable time range 
Screening 
Day −28 to Day −1 
Day −28 to Day −1 
Week 12 
Day 85 
Day 78 to Day 92 
Week 28 
Day 197 
Day 190 to Day 204 
Week 40 
Day 281 
Day 274 to Day 288 
Week 52 
Day 365 
Day 358 to Day 372 
End of Week 12 (Week 12 or at 
early termination before Week 12) 
Day 85 
Day 2 to Day 92 
End of treatment (Week 52 or at 
early termination) 
Day 365 
Day 2 to Day 372 
*:  Day 1 represents the first day of study or reference treatment. The day before the initiation of treatment with the study 
drug or reference drug is expressed as Day −1. 
(5) 
QT assessment (except the reference group) 
Time points defined in analysis 
Reference date* 
Acceptable time range 
Baseline 
Day 1 
Day 1 
Before the initiation of treatment with the 
study drug 
Week 4 or 8 
(before study drug administration) 
Day 29 or Day 57 
Before the initiation of treatment with the 
study drug on Reference date ± 7 
Week 4 or 8 
(after study drug administration) 
Day 29 or Day 57 
2 hours post-dose (reference time, but within 
the range of 1 hour to 4 hours post-dose is 
acceptable) on Reference date ± 7 
 
7.9.3 
Handling of Schedule of Assessments of Pharmacodynamic Variables 
For data obtained after the end of study treatment, data obtained within + 2 days after the last 
dose will be included in analysis. For data after the end of reference treatment, data obtained 
within + 9 days after the last dose will be included in analysis. 
(1) 
Biomarkers and lymphocyte subsets 
Time points defined in analysis 
Reference date* 
Acceptable time range 
Baseline 
Day 1 
Before the initiation of treatment with the 
study drug or reference drug on Day 1 
Week 4 to Week 28** 
Day 7×x + 1 
Day (7×x − 6) to Day (7×x + 8) and before 
the initiation of treatment with the study 
drug or reference drug on the visit day 
Week 52 
Day 365 
Day 358 to Day 372 
End of Week 12 (Week 12 or at 
early termination before Week 12) 
Day 85 
Day 2 to Day 92 
End of treatment (Week 52 or at 
early termination) 
Day 365 
Day 2 to Day 372 
*:  Day 1 represents the first day of study or reference treatment. 
**: Represents the reference date and acceptable time range for Week x. 

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7.9.4 
Handling of Schedule of Assessments of Pharmacokinetic Variables 
(1) 
Trough concentration (except the reference group) 
Time points defined in analysis 
Reference date* 
Acceptable time range 
Baseline 
Day 1 
Before the initiation of treatment with the 
study drug on Day 1 
Weeks 4, 8, 12, 28, and 52** 
Day 7×x + 1 
Day (7×x − 6) to Day (7×x + 8) and within 
19 to 29 hours between the time of treatment 
with the study drug before blood collection 
and the time of blood collection 
*:  Day 1 represents the first day of study treatment. 
**: Represents the reference date and acceptable time range for Week x. 
(2) 
Post-dose concentration (except the reference group) 
Time points defined in analysis 
Reference date* 
Acceptable time range 
Week 4 or Week 8** 
Day 7×x + 1 
Day (7×x − 6) to Day (7×x + 8) and 
within 1 to 4 hours between the time of 
treatment with the study drug before blood 
collection and the time of blood collection 
*: Day 1 represents the first day of study treatment. 
**: Represents the reference date and acceptable time range for Week x. 

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8 
OPERATIONAL AND ADMINISTRATIVE CONSIDERATIONS 
8.1 
Procedure for Clinical Study Quality Control 
8.1.1 
Data Collection 
The investigator is responsible to ensure that all data in the eCRFs and queries are accurate 
and complete and that all entries are verifiable with source documents. These source 
documents should be appropriately maintained by the study center. 
The investigator, sub-investigator, or collaborator will enter data collected using an 
Electronic Data Capture (EDC) system. The investigator, sub-investigator, or collaborator 
will enter the data, in principle within 5 working days from the creation of the data (date of 
visit by the subject, date of obtaining information, etc.). 
In principle, the name of AE must be entered within 5 working days of the date of confirming 
its occurrence. The name of concomitant drug/therapy must also be entered within 5 working 
days of the awareness of its use. Other information to be entered in the eCRF must be entered 
immediately on receipt. 
The monitor should verify the data in the eCRFs with source documents and confirm that 
there are no inconsistencies between them. 
For screening failures, the minimum demographic data (sex, birth date, study region, and 
informed consent date) and, if reason for screening failure is to be obtained, the screening 
failure log (SFL) will be collected. 
Measurements of laboratory tests, pharmacodynamic parameters, and plasma drug 
concentrations will be performed by central laboratory. The Data Science Department of the 
sponsor will obtain the laboratory test results, pharmacodynamic measurements, and plasma 
drug concentration measurements in an electronic format from central laboratory at 
predefined intervals during the study. 
Analysis of Central ECG will be performed by 
 The Data Science 
Department of the sponsor will obtain the quality assured analysis data in an electronic 
format from 
 at predefined timing. 
The central laboratory and 
 will provide the sponsor with a copy of 
the complete and clean data, together with the quality control report. 
8.1.2 
Specification of Source Documents 
Source data must be available at the study center to document the existence of the study 
subjects and substantiate the integrity of study data collected. Source data must include the 
original documents relating to the study as well as those relating to the medical treatment and 
medical history of the subject. 
The following information should be included in the source medical records: 
● 
Demographic data (study region, birth date, sex, height, and body weight) 
● 
Inclusion and exclusion criteria details 

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● 
Participation in study and signed and dated informed consent forms 
● 
Visit dates 
● 
Medical history and physical examination details 
● 
Key efficacy and safety data 
● 
AEs and symptomatic treatment 
● 
The results of the relevant examination (e.g., ECG charts, radiographic data, etc.) 
● 
Laboratory test slips/reports 
● 
Details of dispensing and returning the study drug or reference drug 
● 
Reason for premature discontinuation 
● 
Records of RA diagnosis and evaluation, patient questionnaires (e.g., HAQ-DI, 
SF-36v2®, WPAI) 
● 
Subject questionnaire for CPK monitoring 
● 
Herpes Zoster (shingles) Worksheet 
If the following data are not included in medical records, the entries in the eCRFs are treated 
as source data: 
● 
Dates of AE occurrence and resolution, its severity, seriousness, outcome, causality to 
the study drug, and rationale for the causality 
● 
Route of administration, treatment dates, and reason of use for previous and concomitant 
drugs 
● 
Type, treatment dates, and reason of use for previous and concomitant therapies 
● 
Presence or absence of abnormal 12-lead ECG readings, abnormal findings 
● 
Date, reason, and background/details for discontinuation 
● 
Other comments 
8.1.3 
Clinical Study Monitoring 
The sponsor or delegated CRO is responsible for monitoring the clinical study to ensure that 
subject's human rights, safety, and well-being are protected, that the study is properly 
conducted in adherence to the current protocol and GCP, and study data reported by the 
investigator/sub-investigator are accurate and complete and that they are verifiable with 
study-related records such as source documents. The sponsor is responsible for assigning 
study monitor(s) to this study for proper monitoring. They will monitor the study in 
accordance with planned monitoring procedures. 
8.1.4 
Direct Access to Source Data/Documents 
The investigator and the study site must accept monitoring and auditing by the Sponsor or 
delegated CRO as well as inspections from the IRB/IEC and relevant regulatory authorities. 
In these instances, they must provide all study-related records, such as source documents 
(refer to Section 8.1.2 "Specification of Source Documents") when they are requested by the 
Sponsor monitors and auditors, the IRB/IEC, or regulatory authorities. The confidentiality of 
the subject's identities shall be well protected consistent with local and national regulations 
when the source documents are subject to direct access. 

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8.1.5 
Data Management 
Data management will be coordinated by the Data Science Department of the sponsor in 
accordance with SOPs for data management. All study specific processes and definitions will 
be documented by Data Management. eCRF entry and correction process will be referenced 
in the CRF instructions. Coding of medical terms will be performed using MedDRA. 
 
8.2 
Ethics and Protection of Subject Confidentiality 
8.2.1 
Institutional Review Board (IRB)/ Independent Ethic Committee (IEC) 
Prior to a conclusion of study contracts for the present study, the protocol and documents 
used to obtain patient consent shall be reviewed and approved by the IRBs/IECs of each 
study center in order to ensure that subject's human rights, safety, and well-being are 
protected. 
8.2.2 
Ethical Conduct of the Study 
The investigator(s) and all parties involved in this study should conduct the study in 
adherence to GCP, ICH Guidelines, and the applicable laws/regulations. 
In Japan: 
Moreover, PGx research should be conducted consistent with “Ethical Guidelines for Human 
Genome/Gene Analysis Research” (Notification No. 1 issued by Ministry of Education, 
Culture, Sports, Science and Technology/Ministry of Health, Labour and Welfare 
[MHLW]/Ministry of Economy, Trade and Industry in 2004) and “Clinical Trials with 
Pharmacogenomics Analysis” (Notification from the Director of the Evaluation and 
Licensing Division, Pharmaceutical and Food Safety Bureau, MHLW, dated 30 September 
2008). 
8.2.3 
Informed Consent of Subjects 
8.2.3.1 Subject Information and Consent 
Prior to execution of the clinical study, the investigator should prepare the written informed 
consent form and other written information in collaboration with the sponsor and revise the 
information whenever necessary. The investigator should submit the written or revised 
informed consent form and any other written information to the sponsor to be subject to prior 
approval by IRB/IEC. 
● 
The investigator or other responsible personnel is responsible for explaining the nature 
and purpose of the study and other study-related matters to subjects using the written 
information and for obtaining their full understanding and written consent to participate 
in the study of their own free will. 
● 
The investigator or other responsible personnel who provided explanations (including 
collaborators who gave supportive information, if applicable) and the subject should sign, 
[unique to Japan: seal,] and date the written information. 

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● 
Informed consent must be obtained by the time the observations/examinations during the 
pre-investigational period are performed before treatment with the study drug or 
reference drug. 
● 
The investigator or other responsible personnel must give a copy of the signed [unique to 
Japan: or sealed] consent form to the subject with the written information and store the 
original appropriately in accordance with the rules at the study center concerned. 
● 
The investigator or other responsible personnel should note the following when 
obtaining consent from subjects: 
 No subject may be subjected to undue influence, such as compulsory enrollment into 
a study. 
 The language and expressions used in the written information should be as plain and 
understandable as possible for the subjects. Subjects should be given the opportunity 
to ask questions and receive satisfactory answers to the inquiry, and should have 
adequate time to decide whether or not to participate in the study. Written 
information should not contain any language or contents that causes the subject to 
waive or appears to waive any legal rights, or that releases/mitigates or appears to 
release/mitigate the study center, the investigator/sub-investigator, collaborators, or 
the sponsor from liability for negligence. 
The investigator will retain the signed consent forms, which will be made available (for 
review only) to the study monitor and auditor on request. 
8.2.3.2 Subject Information and Consent for PGx Research 
The study centers in Japan and Korea with approval of the conduct of PGx research should 
obtain the consent to participate in PGx research in addition to the study entry. Prior to 
execution of the clinical study, the investigator should prepare the written informed consent 
form for PGx research in collaboration with the sponsor and revise the information whenever 
necessary. The written or revised written informed consent form and any other written 
information should be submitted to the sponsor and be subject to prior approval by the 
IRB/IEC. 
Only subjects who have given consent for the study entry are subject to the consent for PGx 
research. Subjects can withdraw consent for PGx research only, separately from withdrawal 
of consent for the study entry. Procedures provided in Section 8.2.3.1 Subject Information 
and Consent should also be applied when obtaining consent for PGx research. 
All of the remaining samples for PGx research obtained from the subject who has withdrawn 
consent for PGx research should be disposed of, except those anonymized. 
The signed consent forms will be retained by the investigator and made available (for review 
only) to the study monitor and auditor upon request. 
8.2.3.3 Supply of New and Important Information Influencing the Subject’s Consent 
and Revision of the Written Information 
1. The investigator or other responsible personnel will immediately inform the subject 
orally whenever new information becomes available that may be relevant to the subject's 

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consent or may influence the subject's willingness to continue participation in the study 
(e.g., report of serious adverse drug reactions). The communication should be 
documented in the subject's medical records, and it should be confirmed whether the 
subject is willing to remain in the study or not. 
2. If the investigator recognizes the necessity to revise the written information in the terms 
and conditions applicable to paragraph 1, the written information should be revised 
immediately based upon the newly available information, and be re-approved by the 
IRB/IEC. 
3. The investigator or other responsible personnel should obtain written informed consent 
to continue participation in the study with the revised written information defined in 
paragraph 2, even if subjects are already informed of the relevant information orally. The 
investigator or other responsible personnel who provided explanations (including 
collaborators who gave supportive information, if applicable) and the subject should sign 
and date the informed consent form, or write down his/her name, place a personal seal, 
and date the form. The investigator or other responsible personnel should give a copy of 
the signed [unique to Japan: or sealed] informed consent form to the subject who had 
given consent with the written information and store the original appropriately as done 
for the previous informed consent. 
8.2.4 
Subject Confidentiality 
Medical information of individual subjects obtained as a result of this study is considered 
confidential, and disclosure to third parties is prohibited. Medical information of individual 
subjects may be given only after approval of the subject to the subject’s physician or to other 
appropriate medical personnel responsible for the subject’s well-being. 
The sponsor, its board members or its employee shall not disclose any confidential 
information on subjects obtained during the performance of their duties in the clinical study 
without justifiable reasons. 
All individuals and organizations involved in the study must pay very careful attention to 
protect subjects’ privacy with appropriate measures, for example, by prohibiting the use of 
any private information that may identify a subject (e.g., name or address). These details 
shall be processed in accordance with the applicable laws such as Personal Information 
Protection Law and regulatory requirement(s). 
Even though any individuals involved in the study including the study monitors and auditors, 
may get to know matters related to subject’s privacy due to direct access to source documents, 
or from other sources, they may not leak the content to third parties. 
 
8.3 
Administrative Matters 
8.3.1 
Arrangement for Use of Information and Publication of the Clinical Study 
Information concerning the study drug, patent applications, processes, unpublished scientific 
data, the Investigator's Brochure and other pertinent information is confidential and remains 

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the property of the Sponsor. Details should be disclosed only to the persons involved in the 
approval or conduct of the study. The investigator may use this information for the purpose 
of the study only. It is understood by the investigator that the Sponsor will use the 
information obtained during the clinical study in connection with the development of the 
drug and therefore may disclose it as required to other clinical investigators or to regulatory 
agencies. In order to allow for the use of the information derived from this clinical study, the 
investigator understands that he/she has an obligation to provide the Sponsor with all data 
obtained during the study. 
The study will be considered for publication or presentation at (scientific) symposia and 
congresses. The investigator or other responsible personnel will be entitled to publish or 
disclose the data generated at their respective study center only after submitting all transcripts, 
texts of presentations, and abstracts related to the study to the sponsor at least 90 days prior 
to the intended submission for publication or any other disclosure. Because such disclosure 
of study results is presupposed, it is important that the information concerning the invention 
is protected by a patent, through the preparation and submission of a patent application. 
Moreover, publication of facts and opinions summarized by the investigator is not restricted. 
The sponsor will inform the investigator in writing of any objection or question arising 
within 30 days of receipt of the proposed publication material. After agreement between 
investigator(s) and sponsor, the manuscript can be submitted for publication. 
8.3.2 
Documents and Records Related to the Clinical Study 
The sponsor will provide the investigator or other responsible personnel and/or study center 
with the following: 
● 
Study protocol (and amendments, where applicable) 
● 
Investigator’s Brochure (and amendments, where applicable) 
● 
eCRFs and other related documents, SAE Worksheet 
● 
Study drugs and reference drugs with all necessary documentation 
● 
Study contract 
In order to start the study, the investigator and/or study center is required to provide the 
following documentation to the sponsor: 
● 
Signed Investigator’s Statement in this protocol and eCRF 
● 
Current curricula vitae (CVs) of all investigators 
● 
List of sub-investigators and collaborators 
● 
IRB/IEC approval of the protocol, protocol supplement (if applicable) including a 
membership list with names and qualification (copy) 
● 
Instruction and decision of the head of the study center (if applicable) 
● 
Study contract and memorandum 
● 
Laboratory normal reference ranges (including modification and amendment) 
 

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At the end of the study, the sponsor is responsible for the collection of: 
● 
Other study documentation 
● 
Unused study drugs and reference drugs (if applicable) 
The investigator will archive all study data (e.g., subject identification code list, source 
documents, and investigator’s file) and relevant correspondence. These documents are to be 
kept on file for the appropriate term determined by local regulations (for study centers in the 
US, 2 years from the approval of NDA or termination of IND). The sponsor will archive and 
retain all documents pertaining to the study according to local regulations. 
In Japan: 
The records to be retained at the study sites are the ones listed as essential documents in GCP. 
These records shall be retained by the head of the study site or the record keeper designated 
by the head until notice issued by the Sponsor on completion of the retention period is 
received. These documents are also subject to direct access and should be provided upon 
request from the Sponsor or regulatory authorities. 
 
The following are the major documents to be retained at the study center. 
Source documents (clinical data, documents, and records for preparing the eCRF) 
1. Hospital records, medical records, test records, memoranda, or check lists for evaluation, 
administration records, medication diary (for self-administration in the reference group), 
data recorded by automatic measuring instruments, reproductions or transcripts verified 
as precise copies, microfiche, negative films, microfilms/magnetic media, radiographic 
films, subject files and study-related records kept at either a pharmacy, a laboratory, or 
medical technical office, as well as subject registration forms, laboratory test slips 
including central measurement, worksheets/forms [e.g., questionnaires at CPK 
monitoring, Herpes Zoster (shingles) Worksheet] specified by the sponsor, records of 
clinical coordinators, and records related to the clinical study selected from those 
verified in other departments or hospitals. 
2. Contracts, written informed consent forms, written information, and other documents or 
their copies prepared by the study personnel. 
A letter of request for clinical study (including a request for continuation/amendment), 
letter of request for review, notice of clinical study contract, clinical study contract, 
notification of discontinuation or completion of clinical study, written information for 
informed consent (including revisions), signed and dated written informed consent 
(including revisions), CVs of investigators, list of sub-investigators and collaborators, 
list of signatures and print of seals (copy), and electronic media storing the eCRF data, 
etc. 
3. Documents obtained related to the adequacy of conducting the clinical study by the head 
of the study centers and the protocol, documents obtained related to the adequacy of 
conducting the clinical study whose period exceeds one year or the adequacy of 
continuously conducting the clinical study from which information on adverse drug 

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reactions is obtained, and other documents obtained. 
An agreed-upon protocol (including revisions), Investigator’s Brochure (including 
revisions), SOP for the investigator, materials and information supplied by the sponsor 
(e.g., AE report), matters reported by the investigator (revisions of the protocol, AE 
report, etc.), SOP for the IRB/IEC, the list of names of the IRB/IEC members, material 
for IRB/IEC review (including continuous deliberation), IRB/IEC review records 
(including continuous deliberation), and the review result report of the IRB/IEC 
(including continuous deliberation), etc. 
4. Records of control for study drugs and other duties related to the clinical study 
Procedure for controlling the study drugs, drug inventory and accountability record, 
vouchers for the receipt and return of the study drugs, and other records of the 
prescriptions for concomitant medications 
The documents of the Independent DSMB (minutes, SOPs, and others) shall be retained 
by the sponsor. 
 
● 
[Unique to Japan and Korea: Records of PGx research samples 
The study centers where the conduct of PGx research has been approved should retain the 
Subject Identification Code List and written informed consent form (including amendments) 
for PGx research for up to 15 years after the data lock point in order to comply with the 
subject's consent withdrawal of PGx research and storage of their samples.] 
 
In Korea and Taiwan: 
The investigator and the study site should archive study-related documents in compliance 
with applicable regulatory requirements. The investigator and the study site must take 
measures to prevent accidental or premature destruction of these documents during the 
required retention period. 
8.3.3 
Protocol Amendment and/or Revision 
Any changes to the study that arise after approval of the protocol must be documented as 
protocol amendments and/or revisions. Depending on the nature of the amendment and/or 
revision, either IRB/IEC/regulatory authorities’ approval or notification is required. The 
changes and revisions will become effective only after the approval of the sponsor, the 
investigator, and the IRB/IEC (if applicable), [Unique to Japan: followed by the approval of 
the head of the study center.] 
8.3.4 
Insurance of Subjects and Others 
If a subject suffers any study-related injury, the Sponsor will compensate appropriately 
according to the severity and duration of the damage. However, if it was caused intentionally 
or was due to gross negligence by the study site, the Sponsor will consult with the study site 
about handling the injury, based on the agreed study contract. Compensation for the 
study-related injury is provided by the following procedures:  

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1. If a subject incurs an injury as a result of participation in the clinical study, the study site 
should provide medical treatment and other necessary measures. The Sponsor/delegated 
CRO should be notified of the injury. 
2. When the subject claims compensation from the study site for the above study-related 
injury, or such compensation may be claimed, the study site should immediately 
communicate the fact to the Sponsor/delegated CRO. Both parties should work together 
towards compensation settlement. 
3. The Sponsor shall pay compensation or indemnification and bear expenses necessary for 
the settlement as provided in the clinical contract. 
4. The Sponsor shall make an arranging for insurance and take measures necessary to 
ensure the compensation or indemnification mentioned above. 
8.3.5 
Signatory Investigator for Clinical Study Report 
ICH E3 guidelines recommend and EU Directive 2001/83/EC requires that a final study 
report that forms part of a marketing authorization application be signed by a coordinating or 
principal investigator. The coordinating investigator will have the responsibility to review the 
final study results to confirm to the best of his/her knowledge it accurately describes the 
conduct and results of the study. A coordinating investigator will be selected from the 
participating investigators by sponsor prior to database lock. 
 

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9 
QUALITY ASSURANCE 
The sponsor is implementing and maintaining quality assurance and quality control systems 
with written SOPs to ensure that studies are conducted and data are generated, documented 
(record), and reported in compliance with the protocol, GCP, and applicable regulatory 
requirement(s). 
The Sponsor or Sponsor's designee may arrange to inspect/audit the clinical study at any or 
all study centers. The auditor is independent from the clinical monitoring and project 
management team at the Sponsor. The audit may include on-site review of study-related 
documents/records, eCRF, and source documents. Direct access to these documents will be 
required by the auditors. 
 

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10 
STUDY ORGANIZATION 
10.1 
Independent Data and Safety Monitoring Board (DSMB) 
An independent DSMB will be organized to review the unblinded safety data, to make a 
decision on whether to continue or stop the study, or modify the protocol with respect to the 
safety, and to provide the sponsor with recommendations. The DSMB should follow the 
procedures separately defined in details, including the frequency of meetings, blind-breaking 
and data review. 
 
10.2 
Other Evaluation Committee(s) 
Not applicable. 
 
10.3 
Other Study Organization 
See Attachment. 
 

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10.4 
Registration of Subjects 
Investigator 
or 
sub-investigator 
 
Subject registration center 
 
Central laboratory 
assessments 
 
Obtaining informed 
consent 
Enter subject information 
 
web 
 
 
 
 
 
 
 
 
 
↓ 
 
Confirm inclusion/exclusion of the 
subject 
Subject registration 
 
 
 
 
web 
 
 
 
 
 
 
 
Screening test 
Sample submission 
→ 
 
Laboratory test results 
on the day of screening 
visit 
↓ 
 
Baseline: 
Confirm the eligibility 
based on laboratory test 
results at screening and 
other demographics 
Test results 
← 
↓ 
 
 
 
 
Enter subject information 
 
web 
 
 
 
Confirm inclusion/exclusion of the 
subject 
Registration 
Issue the drug number 
(automatic allocation at Week 0) 
 
 
 
 
Verify the registration 
confirmation form 
Dispense the study drug or 
reference drug 
 
 
web 
 
 
 
↓ 
Enter the visit status at 
Week 12 
 
web 
 
 
 
 
 
Automatically issue drug number at 
each scheduled visit 
(the dose for the placebo group will 
be switched only at Week 12*) 
(Week 4 to Week 48) 
 
 
 
 
Confirm drug number 
Dispense the study drug or 
reference drug 
 
 
web 
 
 
↓ 
Confirm the completion of 
Week 52 
Confirm informed consent 
for extension 
study**/register early 
termination (date of 
termination) 
 
web 
 
 
 
 
 
 
Confirmation/notification of 
eligibility to transfer to the 
extension study** 
 
 
 
 
Confirm notification of 
eligibility to transfer to the 
extension study** 
 
 
web 
 
 
* 
At the Week 12 visit, only subjects in the placebo group will be switched to receiving ASP015K 100 mg 
or ASP015K 150 mg based on the allocation at baseline. 
** 
Only subjects in the ASP015K 100 mg, ASP015K 150 mg, or placebo groups who completed Week 52. 
 

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<Subject registration center> 
 
In Japan: 
URL: 
 
Service available: Everyday (365 days, 24 hours) 
Help desk TEL: 
, FAX: 
 
(Monday to Friday: 9:00-18:00, except national holidays, and 29 December to 4 January) 
 
In Korea and Taiwan: 
URL: 
 
Service available: Everyday (365 days, 24 hours) 
Help desk in Korea 
TEL: 
  FAX : 
 
Help desk in Taiwan 
TEL : 
  FAX : 
 
(Monday to Friday: 9:00-18:00 (Japan time), except national holidays in Japan, and 29 
December to 4 January) 
 
 
The investigator/sub-investigator is responsible for conducting a survey on demographics of 
the candidate subjects and obtaining their written consent. After obtaining written consent, 
the investigator/sub-investigator should make necessary entries in the case registration form 
on the web-based registration system. The subject registration center will notify the 
preregistration results to the study centers via the web-based registration system. 
The investigator/sub-investigator will confirm the inclusion/exclusion criteria at baseline, and 
the investigator/sub-investigator will make the necessary entries in the case registration form 
on the web-based registration system. The registration center will confirm the fulfillment of 
inclusion/exclusion criteria based on the case registration information received and inform 
the study centers of the case inclusion or exclusion via the web-based registration system. 
The investigator/sub-investigator will dispense the study drug or reference drug to the subject 
who is considered “eligible” for study registration. 
 

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11 
REFERENCES 
Aletaha D, Smolen J. The Simplified Disease Activity Index (SDAI) and the Clinical Disease Activity 
Index (CDAI): A review of their usefulness and validity in rheumatoid arthritis. Clin Exp 
Rheumatol 2005;23(Suppl. 39):S100-S108. 
Daniel A, Tuhina N, Alan J, et al. 2010 Rheumatoid arthritis classification: An American College of 
Rheumatology/European League against rhumatism collaborative initiative. Arthritis Rheum 
2010; 62:2569-2581. 
Felson DT, Anderson JJ, Boers M, Bobmardier C, Furst D, Goldsmith C, et al. American College of 
Rheumatology preliminary definition of improvement in rheumatoid arthritis. Arthritis Rheum 
1995;38:727-735. 
Felson DT, Smolen JS, Wells G, Zhang B, Tuyl LHD van, Funovitis J, et al. American College of 
Rheumatology/European League Against Rheumatism Provisional Definition of Remission in 
Rheumatoid Arthritis for Clinical Trials. Arthritis Rheum 2011;63:573-586. 
Fransen J, Riel PLCM van. The Disease Activity Score and the EULAR response criteria. Clin Exp 
Rheumatol 2005;23(Suppl 39):S93-9. 
Fransen J, Welsing P, Keijzer Rd, Riel P van. Disease Activity Scores using C-reactive protein: CRP 
may replace ESR in the assessment of RA disease activity. Ann Rheum 2003;62:151. 
Fries JF, Spitz PW, Young DY. The dimensions of health outcomes: The health assessment 
questionnaire, disability and pain scales. J Rheumatol 1982;9:789-793. 
Hochberg MC, Chang RW, Dwosh I, Lindsey S, Pincus T, Wolfe F. The American College of 
Rheumatology 1991 Revised Criteria for the Classification of Global Functional Status in 
Rheumatoid Arthritis. Arthritis Rheum 1992;35:498-502. 
Kremer JM, Bloom BJ, Breedveld FC, Coombs JH, Fletcher MP, Gruben D, et al. The safety and 
efficacy of a JAK inhibitor in patients with active rheumatoid arthritis. Arthritis Rheum. 
2009;60:1895-1905. 
Mallya RK, de Beer FC, Berry H, Hamilton EDB, Mace BEW, Pepys MB. Correlation of clinical 
parameters of disease activity in rheumatoid arthritis with serum concentration of C-reactive 
protein and erythrocyte sedimentation rate. J Rheumatol 1982;9(2):224-8. 
O’Dell JR. Therapeutic strategies for rheumatoid arthritis. N Engl J Med. 2004;350:2591-602. 
Papageorgiou AC, Wikman LEK. Is JAK3 a new drug target for immunomodulation-based therapies? 
Trends Pharmacol Sci. 2004;25(11):558-62. 
Prevoo MLL, Hof MA van’t, Kuper HH, Leeuwen MA van, Putte LBA van de, Riel PLCM van. 
Modified disease activity scores that include twenty-eight-joint counts. Arthritis Rheum 
1995;38:44-48. 
Ramey DR, Raynauld JP, Fries JF. The health assessment questionnaire 1992: status and review. 
Arthritis Care & Research 1992;5:119-129. 

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Silvia G. Priori, Arthur A.Wilde, et al. HRS/EHRA/APHRS Expert consensus statement on the 
diagnosis and management of patients with inherited primary arrhythmia syndromes. Heart 
Rhythm 2013: 10; 1932-1963 
Reilly MC, Zbrozek AS, Dukes EM. The validity and reproducibility of a work productivity and 
activity impairment instrument. PharmacoEconomics 1993;4(5):353-65 
Smolen JS, Breedveld FC, Schiff MH, Kalden JR, Emery P, Eberl G, et al. A simplified disease 
activity index for rheumatoid arthritis for use in clinical practice. Rheumatology 
2003;42:244-257. 
Steinbrocker O, Traeger CH, Batterman RC. Therapeutic criteria in rheumatoid arthritis. J Am Med 
Assoc. 1949;140(8):659-62. 
Van Gestel AM, Prevoo MLL, Hoff MA van’t, Rijswijk MH van, Putte LBA van de, Riel PLCM van. 
Development and validation of the European League Against Rheumatism response criteria for 
rheumatoid arthritis. Arthritis Rheum 1996;39:34-40. 
Van Gestel AM, Haagsma, CJ, Riel PLCM vav. Validation of RA improvement criteria that include 
simplified joint counts. Arthritis Rheum 1998;41:1845-1850. 
Van der Heijde DM, Hof MA van’t, Riel PL van, Theunisse LA, Lubberts EW, Leeuwen MA van, 
Rijswijk MH van, Putte LB van de. Judging disease activity in clinical practice in rheumatoid 
arthritis: first step in the development of a disease activity score. Ann Rheum Dis 
1990;49:916-920. 
Ware JE. SF-36 Health Survey update. The Use of Psychological Testing for Treatment Planning and 
Outcomes Assessment. 2004;3:693-718. 
Wolfe F. Comparative usefulness of C-reactive protein and erythrocyte sedimentation rate in patients 
with rheumatoid arthritis. J Rheumatol 1997;24:1477-85. 
Actemra®, Drip Infusion, 80 mg, 200 mg, 400 mg, final reports on all-case surveillance. “Rheumatoid 
arthritis” “Active polyarticular juvenile idiopathic arthritis” 
Enbrel®, Drug Interview Form (Revised June 2013 Ver. 21) 
Orencia®, Drip Infusion, 250 mg, information regarding appropriate drug usage Vol. 4. Summary of 
final reports 
Cimzia Subcutaneous Injection 200 mg Syringe CTD, 2.7 Clinical Summary, 2.7.3 Summary of 
Clinical Efficacy, 2.7.3.2 Summary of Results of Individual Studies, 2.7.3.2.2 Comparison of 
Efficacy Results of All Studies, 2.7.3.2.2.1 Japanese Studies (1) Study CDP870-041, (2) Study 
RA0006 22-35 (2012) 
Simponi®, Drug Interview Form (September 2013 Ver. 5) 
Xeljanz®, Drug Interview Form (Revised July 2013 Ver. 3) 
Xeljanz® Tablets, 5 mg CTD, 2.7 Clinical Summary, 2.7.3 Summary of Clinical Efficacy, 2.7.3.3 
Comparison of Results in Subpopulations, 2.7.3.3.1 Comparison of Japanese Population and 
Whole Population in Global Studies (Study No. A3921044) 123-139 (2013) 

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Xeljanz® Tablets, 5 mg CTD, 2.7 Clinical Summary, 2.7.4 Summary of Clinical Safety, 2.7.4.2 
Adverse Events, 2.7.4.2.1.5.1.6 Serious Infections 150-153 (2013) 
Takeuchi T. [The significance of assessing the work productivity in the practice of rheumatoid 
arthritis – For higher treatment goals–]. Rheumatology. 2011;46:288-296. Japanese. 
Tanaka Y. [New target molecules in treatment for rheumatoid arthritis – Will signal-inhibiting 
low-molecular-weight compounds surpass biologics? –]. Inflammation and Immunity. 
2009;17:214-218. Japanese. 
Nakajima A. [Drug therapy for rheumatoid arthritis: Indications, contraindications, and methods of 
use – Antirheumatic drugs (DMARDs)]. Internal Medicine. 2009;103:655-659. Japanese. 
Japan Clinical Oncology Group (JCOG), Japanese Society of Clinical Oncology (JSCO). Common 
Terminology Criteria for Adverse Events (CTCAE) v4.0, Japanese translation, JCOG/JSCO 
Version: 1 February 2010. Available from: http://www.jcog.jp/index.htm 
Humira®, Drug Interview Form (Revised July 2013 Ver. 12) 
Humira®, Subcutaneous Injection, 40 mg, syringe 0.8 mL, information regarding appropriate drug 
usage Vol. 7. (Summary of final reports from 7,740 patients) 
Yamaoka K, Tanaka Y. [Rheumatoid arthritis treatment with Jak3 inhibitors]. Rheumatology. 
2008;40:526-530. Japanese. 
 

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12 
APPENDICES 
APPENDIX <1>: LIST OF PROHIBITED CONCOMITANT 
MEDICATION 
 Biologic DMARD (biological drugs for the treatment of RA) 
Etanercept (except use as a reference drug), anakinra, adalimumab, golimumab, 
infliximab, tocilizumab, abatacept, certolizumab pegol, rituximab, denosumab 
 Non-biologic DMARD* 
MTX, hydroxychloroquine, Salazosulfapyridine, gold, D-penicillamine, leflunomide, 
lobenzarit, actarit, tacrolimus, mizoribine, bucillamine, iguratimod, tofacitinib 
*: MTX, hydroxychloroquine, Salazosulfapyridine, gold, D-penicillamine, lobenzarit, actarit, bucillamine, or 
iguratimod can be administered concomitantly when subjects receive the drug at the same dosage and using the same 
administration schedule from 28 days prior to baseline to the end of treatment with the study drug or reference drug. 
Topical drugs other than those for the treatment of RA may be used concomitantly. 
 Other drugs used in the treatment of RA 
Cyclosporine, cyclophosphamide, azathioprine, minocycline, etc. 
 Corticosteroids** 
Prednisolone, hydrocortisone, hydrocortisone succinate, methylprednisolone, 
methylprednisolone succinate, triamcinolone, triamcinolone acetonide, dexamethasone, 
betamethasone, etc. 
**: Administration of corticosteroids at doses exceeding 10 mg/day in prednisolone equivalent is prohibited. 
Intra-articular, intravenous, intramuscular, or endorectal administration is prohibited. However, suppositories for anal 
disease may be used concomitantly. 
 Oral morphine*** 
Morphine hydrochloride, morphine sulfate 
***: Oral morphine in doses exceeding 30 mg/day (or equivalent amount of opioid analgesic) 
 CYP3A substrates with narrow therapeutic range 
Dihydroergotamine, ergotamine, fentanyl, pimozide, quinidine, temsirolimus, 
disopyramide, etc. 
 Live or live attenuated virus vaccines 
Freeze-dried live attenuated measles vaccine, freeze-dried live attenuated mumps 
vaccine, freeze-dried BCG vaccine, freeze-dried live attenuated varicella vaccine, 
freeze-dried live attenuated rubella vaccine, live oral poliomyelitis vaccine, etc. 
 Articular cartilage protective agents 
Purified sodium hyaluronate (intra-articular injection), chondroitin sulfate (excluding 
eye drops) 
 

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APPENDIX <2>: LABORATORY TESTS 
 
Visit 
Collecting tube* 
[unique to Japan] 
Parameters to be 
analyzed 
Hematology 
Screening, Baseline, 
Week 4, Week 8, Week 
12, Week 16, Week 20, 
Week 24, Week 28, Week 
32, Week 36, Week 40, 
Week 44, Week 48, Week 
52, at early termination, 
follow-up, unscheduled 
2 mL vacutainer tube 
containing EDTA-2K 
Hemoglobin, 
hematocrit, RBC, 
WBC, differential 
WBC, platelet count 
Biochemistry 
Screening, Baseline, 
Week 4, Week 8, Week 
12, Week 16, Week 20, 
Week 24, Week 28, Week 
32, Week 36, Week 40, 
Week 44, Week 48, Week 
52, at early termination, 
follow-up, unscheduled 
9 mL vacutainer tube 
containing the separating 
medium 
For glucose: 2 mL 
vacutainer tube 
containing 
NaF+EDTA-2Na  
For β-D-glucan: 3 mL 
container for blood 
endotoxin/β-D-glucan 
Na, K, Ca, Cl, Mg, 
HCO3, BUN, 
phosphorus, glucose, 
creatinine, ALP, AST 
(GOT), ALT (GPT), 
γ-GTP, TBL, total 
protein, albumin, uric 
acid, CPK, LDH, serum 
amylase, eGFR, 
β-D-glucan  
Biochemistry (at CPK 
monitoring) 
At CPK monitoring 
4 mL vacutainer tube 
containing the separating 
medium 
CK-MB, troponin-T, 
aldolase 
Fasting lipid profile test 
Baseline, Week 12, Week 
20, Week 28, Week 40, 
Week 52, at early 
termination, follow-up, 
unscheduled 
(Included among 
biochemistry tests) 
Total cholesterol, LDL, 
HDL, triglycerides 
Tuberculosis test 
(When performed at the 
central laboratory) 
Screening 
10 mL vacutainer tube 
containing heparin Na 
Interferon γ titer 
Hepatitis test 
Screening 
6 mL vacutainer tube 
containing the separating 
medium 
HBs antigens, HBs 
antibodies, HBc 
antibodies, and HCV 
antibodies 
Hepatitis DNA test 
Screening 
 
If a subject is positive for 
HBc antibodies or HBs 
antibodies, tests should be 
performed at the 
following visits: 
Baseline, Week 4, Week 
8, Week 12, Week 16, 
Week 20, Week 24, Week 
28, Week 32, Week 36, 
Week 40, Week 44, Week 
48, Week 52, at early 
termination, follow-up, 
unscheduled 
5 mL vacutainer tube 
containing the separating 
medium 
HBV-DNA assay 

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Urinalysis 
Screening, Baseline, 
Week 4, Week 8, Week 
12, Week 16, Week 20, 
Week 24, Week 28, Week 
32, Week 36, Week 40, 
Week 44, Week 48, Week 
52, at early termination, 
follow-up, unscheduled 
For urinalysis: 10 mL 
light-blocking urine 
collection tubes 
For urine microscopic 
examination: 10 mL urine 
collection tubes 
pH, specific gravity, 
protein, glucose, keton 
bodies, bilirubin, occult 
blood, sediment 
Pregnancy testing 
Screening, Baseline, 
Week 4, Week 8, Week 
12, Week 16, Week 20, 
Week 24, Week 28, Week 
32, Week 36, Week 40, 
Week 44, Week 48, Week 
52, at early termination, 
follow-up, unscheduled 
Serum pregnancy test 
(Included among 
biochemistry tests) 
 
Urine pregnancy test 
(In-hospital testing) 
Human chorionic 
gonadotropin (hCG) 
Acute phase reactants 
Screening (CRP only), 
Baseline, Week 4, Week 
8, Week 12, Week 16, 
Week 20, Week 24, Week 
28, Week 32, Week 36, 
Week 40, Week 44, Week 
48, Week 52, at early 
termination, follow-up, 
unscheduled 
(Included among 
biochemistry tests) 
CRP 
In-hospital testing 
ESR 
PK 
(Assessment of trough 
concentration) 
Baseline, Week 4, Week 
8, Week 12, Week 28, 
Week 52, at early 
termination 
2 mL vacutainer tubes 
containing EDTA-3K 
Concentrations of 
ASP015K and its 
metabolites H1, H2, 
and H4 
Additional PK 
(for post-dose 
concentration) 
Week 4 or Week 8 
2 mL vacutainer tubes 
containing EDTA-3K 
Concentrations of 
ASP015K and its 
metabolites H1, H2, 
and H4 
PD 
Baseline, Week 4, Week 
8, Week 12, Week 28, 
Week 52, at early 
termination, follow-up, 
unscheduled 
2 mL vacutainer tubes 
containing EDTA-2Na 
(MMP-3 is included 
among biochemistry 
tests.) 
VEGF 
MMP-3 
Baseline, Week 4, Week 
8, Week 12, Week 28, 
Week 52, at early 
termination, follow-up, 
unscheduled 
2 mL vacutainer tubes 
containing EDTA-2K 
Lymphocyte subset 
Pharmacogenomics 
(Only at approved study 
centers) 
After obtaining the 
subject’s consent for PGx 
5 mL vacutainer tubes 
containing EDTA-2K 
PGx analysis 
*: Types of collecting tube used at Korea and Taiwan are described in the laboratory handling manual. 

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APPENDIX <3>: EVENTS ALWAYS CONSIDERED SERIOUS 
If any of the following events occurs during the study, it should be regarded as an SAE and 
must be reported in accordance with Section 5.5.5 Reporting of Serious Adverse Events 
(SAEs). 
● 
Acute hepatic failure 
● 
Renal failure acute 
● 
Acute respiratory failure 
● 
Agranulocytosis 
● 
Anaphylactic reaction, anaphylactic shock 
● 
Malignant tumor 
● 
Aplastic anaemia 
● 
Endotoxic shock (confirmed or suspected) 
● 
Confirmed or suspected transmission of infectious agents by marketed product 
● 
Congenital anomalies 
● 
Hepatic necrosis 
● 
Malignant hypertension 
● 
Pulmonary fibrosis 
● 
Pulmonary hypertension 
● 
Sclerosing syndromes 
● 
Convulsion (only central neurological seizure) 
● 
Torsades de pointes 
● 
Toxic epidermal necrolysis 
● 
Ventricular fibrillation 
Note: Hy’s Law cases should be regarded as SAE. 
See Appendix 4 “Liver Safety Monitoring and Assessment.” 
 

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APPENDIX <4>: LIVER SAFETY MONITORING AND ASSESSMENT 
If laboratory testing for a subject enrolled in the study and receiving the study drug or 
reference drug reveals an increase in serum aminotransferase (ALT, AST) > 3 × ULN or 
TBL > 2 × ULN, the investigator/sub-investigator should repeat at least 4 parameters (ALT, 
AST, ALP, and TBL) of the usual hepatic function test parameters. Retesting should be 
performed between 48 hours and 72 hours after notification of the test results. For studies for 
which a central laboratory is used, alerts will be generated by the central laboratory regarding 
moderate and marked liver abnormality to inform the investigator or other responsible 
personnel and the sponsor. Subjects should be asked if they have any symptoms suggestive of 
hepatobiliary dysfunction by the investigator/sub-investigator. 
Definition of Hepatic Function Abnormal 
Confirmed hepatic function abnormal will be characterized as moderate (hepatocellular 
failure type or cholestasis type) or marked (mixed type) based on the ULN as follows: 
 
 
ALT or AST 
 
 
TBL 
Moderate 
Hepatocellular failure type 
or 
cholestasis type 
> 3 × ULN 
or 
> 2 × ULN 
 
 
 
 
Marked 
Mixed type 
> 3 × ULN 
and 
> 2 × ULN 
 
In addition, the subject with any of the following should be considered to have marked 
(severe) hepatic function abnormal. 
ALT or AST > 8 × ULN 
ALT or AST > 5 × ULN for more than 2 weeks 
ALT or AST > 3 × ULN and INR > 1.5 
ALT or AST > 3 × ULN with the appearance of fatigue, nausea, vomiting, right upper 
quadrant pain or tenderness, pyrexia, rash and/or eosinophilia (> 5%) 
If the investigator/sub-investigator determines that abnormal liver function results, other than 
as described above, qualify as moderate or marked abnormalities, they should conduct 
additional monitoring and follow-up. 
Follow-up Procedures 
Confirmed moderate and marked hepatic function abnormal should be thoroughly 
characterized by obtaining appropriate expert consultations, detailed pertinent history, 
physical examination and laboratory tests by the investigator/sub-investigator. The 
investigator should complete the liver abnormality case report form (LA-CRF) or an 
appropriate document. Subjects with confirmed abnormal liver function test results should be 
followed as described below by the investigator/sub-investigator. 

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If moderate liver abnormality is confirmed, re-testing should be performed every 2 to 3 times 
a week. If the abnormal test values stabilize or the patient is asymptomatic after the study 
drug or reference drug is withdrawn, re-testing should be performed at a frequency of once a 
week or less. 
 
Marked hepatic function abnormal, in the absence of another etiology, may be considered an 
important medical event and reported as an SAE by the investigator. The sponsor should be 
contacted and informed of all subjects for whom marked hepatic function abnormal possibly 
attributable to study drug or reference drug is observed. 
To further assess the findings of hepatic function abnormal, the investigator/sub-investigator 
is expected to: 
Obtain a more detailed history of symptoms and prior or concurrent diseases. Symptoms and 
new onset-diseases should be recorded as “AEs” on the AE page of CRF. Illnesses and 
conditions such as hypotensive events, and decompensated cardiac disease that may lead to 
secondary liver abnormalities should be noted. Non-alcoholic steatohepatitis (NASH) is seen 
in obese hyperlipoproteinemic and/or diabetic patients and may be associated with 
fluctuating serum aminotransferase (ALT, AST) levels. The investigator/sub-investigator 
should ensure that the medical history form captures any illness that pre-dates study 
enrollment that may be relevant in assessing hepatic function. 
Obtain a history of concomitant drug use (including non-prescription medication, 
complementary and alternative medications), alcohol intake, drug abuse, and special diets. 
Medications, including dose, should be entered on the concomitant medication page of CRF. 
Information on alcohol, other substance use, and diet should be entered into the LA-CRF or 
an appropriate document. 
Obtain a history of exposure to environmental chemical agents. 
Based on the subject’s history, other testing may be appropriate including: 
● 
Acute viral hepatitis subtypes (A, B, C, D, E, or other infectious agents) 
● 
Ultrasound or other imaging to assess biliary tract disease 
● 
Other laboratory tests including INR, direct bilirubin 
Consider gastroenterology or hepatology consultations 
Enter the results for any additional testing and possible etiology into the LA-CRF or an 
appropriate document. 
 
Study Discontinuation 
In the absence of an explanation for liver function test raised such as viral hepatitis, 
pre-existing or acute liver disease, or exposure to other agents associated with liver injury or 
when the investigator/sub-investigator determines that it is not in the subject’s best interest to 
continue study enrollment, the subject may be discontinued from the study by the 

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investigator/sub-investigator. Discontinuation of treatment with the study drug or reference 
drug should be considered if any of the following applies: 
ALT or AST > 8 × ULN 
ALT or AST > 5 × ULN for more than 2 weeks 
ALT or AST > 3 × ULN and (TBL > 2 × ULN or INR > 1.5) 
ALT or AST > 3 × ULN with the appearance of fatigue, nausea, vomiting, right upper 
quadrant pain or tenderness, fever, rash, and/or eosinophilia (> 5%) 
In addition, if close monitoring for a subject with moderate or marked hepatic function 
abnormal is not possible, the study drug or reference drug should be discontinued by the 
investigator. 
Reference 
See “Guidance for Industry on Drug-Induced Liver Injury: Premarketing Clinical Evaluation,” 
published by the FDA in July 2009. 
 

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APPENDIX <5>: 1987 ACR CRITERIA FOR THE CLASSIFICATION 
OF RA 
For classification purposes, a patient shall be said to have RA if he/she has satisfied at least 4 
of these 7 criteria. Criteria [1] through [4] must have been present for at least 6 weeks. 
Criterion 
Definition 
[1] Morning stiffness 
Morning stiffness in and around the joints, lasting at least 1 hour 
before maximal improvement 
[2] Arthritis of 3 or more joint 
areas 
At least 3 joint areas simultaneously have had soft tissue swelling 
or fluid (not bony overgrowth alone) observed by a physician. The 
14 possible areas are right or left PIP, MCP, wrist, elbow, knee, 
ankle, and MTP joints. 
[3] Arthritis of hand joints 
At least 1 area swollen (as defined above) in a wrist, MCP, or PIP 
joint 
[4] Symmetric arthritis 
Simultaneous involvement of the same joint areas (as defined in 
[2]) on both sides of the body (bilateral involvement of PIPs, 
MCPs, or MTPs is acceptable without absolute symmetry) 
[5] Rheumatoid nodules 
Subcutaneous nodules, over bony prominences, or extensor 
surfaces, or in juxtaarticular regions, observed by a physician 
[6] Serum rheumatoid factor 
Demonstration of abnormal amounts of serum rheumatoid factor by 
any method for which the result has been positive in ≤ 5% of 
normal control subjects 
[7] Radiographic changes 
Radiographic changes typical of RA on posteroanterior hand and 
wrist radiographs, which must include erosions or unequivocal 
bony decalcification localized in or most marked adjacent to the 
involved joints (osteoarthritis changes alone do not qualify) 
 
[Armett FC et al, 1988] 
 

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APPENDIX <6>: 2010 ACR-EULAR CLASSIFICATION CRITERIA 
FOR RA 
1. If a patient has at least 1 joint with synovitis not explained by another disease and scores 
≥ 6 in the scoring system of 4 categories, he/she is assessed as having “definite RA.” 
Joint involvementa) 
1 large jointb) 
0 
2–10 large joints 
1 
1–3 small jointsc) 
2 
4–10 small joints 
3 
≥ 11 joints (at least 1 small joint) 
5 
Serology 
RF8 (−) and anti-CCP antibody (−) 
0 
Low positive RF or low positive anti-CCP 
antibody 
2 
High positive RF or high positive anti-CCP 
antibody 
(High: > 3 × ULN) 
3 
Acute phase reactants 
Normal CRP and normal ESR 
0 
Abnormal CRP or abnormal ESR 
1 
Duration of symptoms 
< 6 weeks 
0 
≥ 6 weeks 
1 
a): The distal interphalangeal joints, first CMC joints, and first MTP joints are excluded from assessment. 
b): Large joints: Shoulder, elbow, hip, knee, and ankle joints 
c): Small joints: PIP joints, MCP joints, 2–5 MTP joints, first IP joints, and wrist joints 
 
[Daniel A et al, 2010] 
 

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APPENDIX <7>: CRITERIA FOR THE CLASSIFICATION OF 
GLOBAL FUNCTIONAL STATUS IN RA (1991 
REVISED CRITERIA) 
[Classification of Global Functional Status in RA: Class] 
Class I  
Complete functional capacity with ability to carry on all usual duties without 
handicaps 
Class II 
Functional capacity adequate to conduct normal activities despite handicap or 
discomfort or limited mobility of one or more joints 
Class III 
Functional capacity adequate to perform only few or none of the duties of usual 
occupation or of self-care 
Class IV 
Largely or wholly incapacitated with patient bedridden or confined to wheelchair, 
permitting little or no self-care 
 
[Hochberg et al, 1992] 
 
APPENDIX <8>: CLASSIFICATION OF DISEASE 
STAGE/PROGRESSION OF RA 
Stage I: Early 
1 
X-rays show no evidence of bone destruction. 
2 
X-rays may show radiological osteoporosis. 
Stage II: 
Intermediate 
1. 
X-rays show osteoporosis which may or may not be accompanied 
by mild destruction of subchondral bone. Mild bone destruction 
may be observed. 
2. 
Joint mobility may be limited, but there is no joint deformation. 
3. 
Muscle atrophy surrounding the joint is present. 
4. 
Lesions in extra-articular soft tissue, such as nodules and 
tenosynovitis, may be present. 
Stage III: Advanced/ 
Progressive 
1. 
In addition to osteoporosis, X-rays show destruction of bone and 
cartilage. 
2. 
Joint deformities such as subluxation, ulnar displacement, or 
hyperextension are present, unaccompanied by fibrous or bony 
ankylosis. 
3. 
Exaggerated muscle atrophy is present. 
4. 
Lesions in extra-articular soft tissue, such as nodules and 
tenosynovitis, may be present. 
Stage IV: End Stage 
1. 
Fibrous or bony ankylosis is present. 
2. 
Other symptoms meet criteria for Stage III. 
[Steinbrocker O. 1949] 
 
 
 
(GPF 3.03)