A Multicenter, Randomized, Double-blind Study Evaluating the Pharmacokinetics, Efficacy, Safety, and Immunogenicity of Multiple Switches Between Humira® (Adalimumab [US]) and ABP 501 Compared With Continued Use of Adalimumab in Subjects With Moderate to Severe Plaque Psoriasis
Phase: PHASE3
Conditions: Plaque Psoriasis
Sponsor: Amgen

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 1 of 87 
Title Page 
Protocol Title: 
A Multicenter, Randomized, Double-blind Study 
Evaluating the Pharmacokinetics, Efficacy, 
Safety, and Immunogenicity of Multiple Switches 
Between Humira® (adalimumab [US]) and 
ABP 501 Compared With Continued Use of 
Adalimumab in Subjects With Moderate to 
Severe Plaque Psoriasis 
Short Title: 
A Study to Investigate the Impact of Switching 
Between ABP 501 and Adalimumab for the 
Treatment of Subjects with Moderate to Severe 
Plaque Psoriasis 
Compound: 
ABP 501 
Indication: 
Moderate to Severe Plaque Psoriasis 
Study Sponsor: 
Amgen Inc. 
One Amgen Center Drive 
Thousand Oaks 
CA 91320-1799, US 
Protocol Number: 
20200497 
Study Phase: 
Phase 3 
Regulatory Agency Identifying 
Number: 
IND: 111714 
EudraCT: 2021-000542-18 
Approval Date: 
Final 1.0, 03 Jun 2021 
NCT Number: NCT05073315
This NCT number has been applied to the document
for purposes of posting on Clinicaltrials.gov

Product: ASP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Protocol Signature Page - Sponsor Signatory: 
Page 2 of 87 
This protocol has been reviewed and approved by the representative(s) listed below. Any 
modification of the protocol must be agreed upon by the sponsor and the investigator and must 
be documented in writing. 
Amgen Inc. representative(s): 
 MD, PhD 
Executive Medical Director 
Print Name 
Title 
Signature 
Date 
AMGEN
® 

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 3 of 87 
 
Protocol Signature Page – Contract Research Organization 
This protocol has been reviewed and approved by the representative(s) listed below.  Any 
modification of the protocol must be agreed upon by the sponsor and the investigator and must 
be documented in writing.   
Contract research organization representative(s): 
 
Print Name 
 
Title 
Signature 
 
Date (DD MMM YYYY) 
 
 

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 4 of 87 
 
Protocol Signature Page – Investigator 
I have read this protocol, which has been agreed to by Amgen Inc.  and given 
approval/favorable opinion by the Institutional Review Board/Independent Ethics Committee, 
and I agree that it contains all necessary details for my staff and I to conduct this study as 
described.  I will provide copies of the protocol and any amendments to all study personnel 
under my supervision and provide access to all information provided by Amgen Inc.  or their 
specified designees.  I will discuss the material with the study personnel to ensure that they are 
fully informed about the study.   
I understand that information contained in or pertaining to this protocol is confidential and should 
not be disclosed, other than to those directly involved in the execution or the ethical review of 
the study, without written authorization from Amgen Inc.  It is, however, permissible to provide 
information to a subject in order to obtain consent.   
I agree to conduct this study according to this protocol and to comply with its requirements, 
subject to ethical and safety considerations and guidelines, and to conduct the study in 
accordance with the general guidelines indicated in the Declaration of Helsinki, International 
Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) 
guidelines on Good Clinical Practice (GCP), and applicable national or regional regulatory 
requirements.   
I agree to comply with the procedures described for data recording and reporting and to permit 
monitoring and auditing by Amgen Inc. and inspection by the appropriate regulatory authorities.   
I agree to make my subjects’ study records available to Amgen Inc.  personnel, their 
representatives and relevant regulatory authorities in order to verify data that I have entered into 
the case report forms.  I will retain the study related essential documents until Amgen Inc.  
indicates that they are no longer needed.  I am aware of my responsibilities as an investigator 
as provided by Amgen Inc.   
I agree to ensure that Financial Disclosure Statements will be completed by me (including, if 
applicable, my spouse [or legal partner] and dependent children) and my sub investigators 
(including, if applicable, their spouses [or legal partners] and dependent children) at the start of 
the study and for up to 1 year after the study is completed, if there are changes that affect my 
financial disclosure status.   

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 5 of 87 
 
I understand that Amgen Inc.  may decide to suspend or prematurely terminate the study at any 
time for whatever reason; such a decision will be communicated to me in writing.  Conversely, 
should I decide to withdraw from execution of the study, I will communicate my intention 
immediately in writing to Amgen Inc.   
Investigator: 
 
Print Name 
 
Title 
Institution 
 
 
Signature 
 
Date (DD MMM YYYY) 
 

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 6 of 87 
 
Table of Contents 
 
Table of Contents ....................................................................................................................... 6 
1 
Protocol Summary ..............................................................................................................10 
1.1 
Synopsis .........................................................................................................................10 
1.2 
Schema ..........................................................................................................................16 
1.3 
Schedule of Assessments ...............................................................................................17 
2 
Introduction .........................................................................................................................19 
2.1 
Study Rationale...............................................................................................................19 
2.2 
Background .....................................................................................................................20 
2.3 
Benefit/Risk Assessment ................................................................................................20 
2.4 
Overall Benefit: Risk Conclusion .....................................................................................21 
3 
Objectives and Endpoints ...................................................................................................22 
4 
Study Design ......................................................................................................................23 
4.1 
Overall Design ................................................................................................................23 
4.2 
Scientific Rationale for Study Design ..............................................................................24 
4.2.1 
Subject Input into Design ............................................................................................24 
4.3 
Justification for Dose .......................................................................................................25 
4.4 
End of Study Definition....................................................................................................25 
5 
Study Population .................................................................................................................25 
5.1 
Inclusion Criteria .............................................................................................................25 
5.2 
Exclusion Criteria ............................................................................................................27 
5.3 
Subject Enrollment ..........................................................................................................30 
5.4 
Lifestyle Considerations ..................................................................................................30 
5.4.1 
Meals and Dietary Restrictions ....................................................................................30 
5.4.2 
Caffeine, Alcohol, and Tobacco ...................................................................................30 
5.4.3 
Activity ........................................................................................................................31 
5.4.4 
Coronavirus Disease 2019 Considerations ..................................................................31 
5.4.5 
Coronavirus Disease 2019 Vaccination Considerations ..............................................31 
5.5 
Screen Failures ...............................................................................................................31 
6 
Investigational Product ........................................................................................................32 
6.1 
Investigational Products Administered ............................................................................32 
6.1.1 
ABP 501 Dosage Form ...............................................................................................33 

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 7 of 87 
 
6.1.2 
Adalimumab Dosage Form ..........................................................................................33 
6.2 
Preparation, Handling, Storage, and Accountability ........................................................33 
6.3 
Investigational Product Complaints .................................................................................34 
6.4 
Measures to Minimize Bias: Blinding and Randomization ...............................................35 
6.4.1 
Blinding .......................................................................................................................35 
6.4.2 
Randomization ............................................................................................................36 
6.5 
Investigational Product Compliance ................................................................................36 
6.6 
Concomitant Therapy ......................................................................................................37 
6.6.1 
Prohibited Treatments .................................................................................................37 
6.6.2 
Prior and Concomitant Therapy ...................................................................................37 
6.7 
Dose Modification ...........................................................................................................38 
6.8 
Intervention After the End of the Study ............................................................................39 
7 
Discontinuation of Investigational Product and Subject Discontinuation ..............................40 
7.1 
Discontinuation of Investigational Product .......................................................................40 
7.2 
Subject Discontinuation/Withdrawal from the Study ........................................................41 
7.3 
Loss of Subjects to Follow-up .........................................................................................42 
8 
Study Assessments and Procedures ...................................................................................43 
8.1 
Efficacy Assessments .....................................................................................................44 
8.1.1 
Psoriasis Area and Severity Index ...............................................................................44 
8.1.2 
Static Physical Global Assessment .............................................................................44 
8.1.3 
Affected Body Surface Area ........................................................................................44 
8.2 
Safety Assessments .......................................................................................................45 
8.2.1 
Physical Examinations ................................................................................................45 
8.2.2 
Vital Signs ...................................................................................................................45 
8.2.3 
Tuberculosis Testing ...................................................................................................45 
8.2.4 
Chest Radiography .....................................................................................................46 
8.2.5 
Clinical Safety Laboratory Assessments .....................................................................46 
8.3 
Adverse Events and Serious Adverse Events .................................................................47 
8.3.1 
Definitions ...................................................................................................................47 
8.3.2 
Assessments of Adverse Events .................................................................................51 
8.3.3 
Causality .....................................................................................................................51 
8.3.4 
Documenting and Reporting of Adverse Events ..........................................................52 
8.3.5 
Pregnancy ...................................................................................................................56 
8.3.6 
Events of Interest ........................................................................................................57 

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 8 of 87 
 
8.4 
Treatment of Overdose ...................................................................................................57 
8.5 
Pharmacokinetics ............................................................................................................57 
8.6 
Pharmacodynamics ........................................................................................................57 
8.7 
Genetics .........................................................................................................................57 
8.8 
Biomarkers ......................................................................................................................58 
8.9 
Immunogenicity Assessments .........................................................................................58 
9 
Statistical Considerations ....................................................................................................59 
9.1 
General Considerations ..................................................................................................59 
9.2 
Statistical Hypotheses .....................................................................................................59 
9.3 
Sample Size Determination .............................................................................................60 
9.4 
Populations for Analysis ..................................................................................................60 
9.5 
Planned Analyses ...........................................................................................................61 
9.5.1 
Primary Endpoints .......................................................................................................61 
9.5.2 
Secondary Endpoint(s) ................................................................................................62 
9.5.3 
Safety Endpoints .........................................................................................................63 
9.5.4 
Other Analyses ...........................................................................................................63 
9.5.5 
Demographic and Baseline Characteristics .................................................................64 
9.5.6 
Exposure to Investigational Product ............................................................................65 
9.5.7 
Exposure to Prior and Concomitant Medication ...........................................................65 
9.5.8 
Subgroup Analyses and Covariates ............................................................................65 
9.6 
Interim Analyses .............................................................................................................65 
10 Supporting Documentation and Operational Considerations ...............................................66 
10.1 Appendix 1: Regulatory, Ethical, and Study Oversight Considerations ............................66 
10.1.1 
Regulatory and Ethical Considerations ........................................................................66 
10.1.2 
Informed Consent Process ..........................................................................................67 
10.1.3 
Data Monitoring Committee .........................................................................................69 
10.1.4 
Financing and Insurance .............................................................................................70 
10.1.5 
Data and Records Management ..................................................................................70 
10.1.6 
Publication Policy ........................................................................................................74 
10.1.7 
Auditing and Monitoring ...............................................................................................75 
10.1.8 
Data Protection ...........................................................................................................77 
10.1.9 
Protocol Approval and Amendment .............................................................................77 
10.1.10 Study and Site Start and Closure ................................................................................78 
10.2 Appendix 2: Contraceptive Guidance and Collection of Pregnancy Information ..............78 

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 9 of 87 
 
10.3 Appendix 3: Static Physician’s Global Assessment Scale ...............................................84 
10.4 Appendix 4: Abbreviations and Trademarks ....................................................................85 
11 References .........................................................................................................................87 
List of Figures 
Figure 1–1 
Study Schema ...................................................................................................16 
List of Tables 
Table 1-1. 
Schedule of Assessments ..................................................................................17 
Table 1-2. 
Tolerance Windows for Pharmacokinetic Endpoint Sample Collection ...............18 
Table 3-1. 
Objectives and Endpoints ..................................................................................22 
Table 4-1. 
Investigational Product Groups ..........................................................................23 
Table 6-1. 
Investigational Product(s) Administered .............................................................32 
Table 8-1. 
Protocol-required Safety Laboratory Assessments .............................................47 
Table 9-1. 
Populations for Analysis .....................................................................................61 
 

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 10 of 87 
 
1 Protocol Summary 
1.1 Synopsis 
Protocol Title: A Multicenter, Randomized, Double-blind Study Evaluating the 
Pharmacokinetics, Efficacy, Safety, and Immunogenicity of Multiple Switches Between Humira® 
(Adalimumab [US]) and ABP 501 Compared With Continued Use of Adalimumab in Subjects 
With Moderate to Severe Plaque Psoriasis 
Sponsor Protocol No.: 20200497 
Study Phase: Phase 3 
Sponsor: Amgen Inc. 
Rationale 
The current study is designed to investigate the pharmacokinetics (PK), efficacy, safety, and 
immunogenicity of multiple switches between adalimumab (Humira®) and ABP 501 compared 
with continued use of adalimumab in subjects with moderate to severe plaque psoriasis (Ps).   
Objectives and Endpoints: 
Objectives 
Endpoints 
Primary Objective: 
Primary Endpoints: 
• 
To demonstrate similarity of PK in subjects after 
multiple switches between adalimumab and 
ABP 501, compared to subjects receiving 
continued use of adalimumab. 
Pharmacokinetic parameters: 
• 
AUCtau between week 28 and week 30.   
• 
Cmax between week 28 and week 30.   
Secondary Objective: 
Secondary Endpoints: 
• 
To assess the efficacy, safety, and immunogenicity 
in subjects after multiple switches between 
ABP 501 and adalimumab compared with subjects 
receiving continued use of adalimumab.   
Pharmacokinetic related Endpoints: 
• 
tmax between week 28 and week 30.   
• 
Ctrough between week 14 and week 28.   
Efficacy related Endpoints: 
• 
PASI percent improvement from baseline (day 1) to 
week 30.   
• 
PASI 75 response at week 30.   
• 
PASI 90 response at week 30.   
• 
PASI 100 response at week 30.   
Safety related Endpoints: 
• 
Treatment-emergent adverse events and serious 
adverse events, post randomization.   
• 
Events of interest, post randomization.   

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 11 of 87 
 
Objectives 
Endpoints 
Immunogenicity-related Endpoints: 
• 
Incidence of ADAs, post randomization 
ADAs = antidrug antibodies; AUCtau = area under the curve from time 0 over the dosing interval; Cmax = maximum 
concentration; Ctrough = trough concentration; PASI = Psoriasis Area and Severity Index; tmax = time of maximum 
concentration 
 
Overall Design: 
This is a randomized, double-blind, phase 3 study in adult subjects with moderate to severe Ps.   
The total duration of study participation for each subject will be about 36 weeks, with up to 
4 weeks for screening and approximately 32 weeks after the first investigational product 
administration.   
The study is composed of two periods.  A lead-in period of treatment with adalimumab (weeks: 
1 to 12) followed by a randomized two parallel arm period (weeks: 12 to 32).  Subjects will 
receive an initial 6 doses of adalimumab on week 1/day 1 (
 mg loading dose), 1 week later on 
week 2/day 8 (
 mg), then at 2 weeks interval on week 4, week 6, week 8, and week 10 
(
 mg), administered subcutaneously (SC).  At week 12, subjects with Psoriasis Area and 
Severity Index (PASI) ≥ 50 (PASI 50) response will be randomized to either the continued-use 
group or switching group in a 1:1 ratio, stratified by geographic region and prior biologic use at 
baseline (week 1/day 1, yes vs. no).  Subjects achieving less than PASI 50 response at week 12 
visit will be considered non-responders and will be discontinued from the study at week 12.  
These subjects will be asked to complete End of Study (EOS) Visit procedures. Subjects 
randomized to the continued-use group will continue on adalimumab every 2 weeks (Q2W) with 
last dose at week 28.  Subjects randomized to the switching group will switch to ABP 501 Q2W 
at week 12 (dosed week 12 and week 14), then back to adalimumab Q2W at week 16 (dosed 
week 16 and week 18), and again to ABP 501 Q2W at week 20 (dosed week 20, week 22, 
week 24, week 26, and last dose at week 28).   
All enrolled subjects not randomized at week 12 will be considered lead-in failures and the 
lead-in failure reason will be documented.  
An EOS Visit will be conducted at week 32.   
Disclosure Statement: This is a parallel group, treatment study with 2 arms that are both 
subject and investigator blinded.   

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 12 of 87 
 
Number of Arms: Continued-use group 
Switching group 
Number of Subjects and Statistical Considerations: 
Approximately 414 subjects will be enrolled to receive adalimumab during the lead-in period.  
Subjects with prior biologic use for psoriasis will be capped at 50% of the total enrolled subjects.  
This sample size will ensure approximately 342 subjects will be randomized at week 12 after the 
lead-in period, considering 17% lead-in failures, in a 1:1 ratio to the continued-use group or the 
switching group.  The randomization will be stratified by prior biologic use for psoriasis at 
baseline (week 1/day 1, yes vs. no) and geographic region.  The number of subjects enrolled 
may be adjusted during the study with the actual lead-in failure rate seen to ensure 
approximately 342 subjects will be randomized at week 12. Subjects already enrolled will be 
allowed to be randomized at week 12.  The sample size of 342 randomized subjects will provide 
at least 90% power to demonstrate similarity of the primary PK endpoints based on the Two 
One-Sided Tests at a 0.05 significance level, assuming a between-subject variability (as 
measured by coefficient of variation) of 53% for ABP 501 and adalimumab, a true geometric 
mean ratio (GMR) of 1 between ABP 501 and adalimumab, a similarity margin of 0.8, 1.25, and 
15% drop-outs after randomization through week 30 (including subjects who discontinue the 
study prior to week 28 and those reaching week 28 but do not have evaluable primary PK 
endpoints between weeks 28 and 30).   
Intervention Groups and Duration: 
The total duration of study participation for each subject will be about 36 weeks, with up to 4 
weeks for screening and approximately 32 weeks after the first investigational product 
administration.   
Dose regimens: Continued-use of adalimumab (adalimumab 
 mg or 
 mg, SC injection) and 
switching group (adalimumab 
 mg or 
 mg, ABP 501 
 mg, SC injection).   

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 13 of 87 
 
Reference Group: 
Adalimumab 
Continued-use Group 
Continued-use of adalimumab administered by SC injection using prefilled 
syringes at a dose of 
 mg (2 x 
 mg loading dose) on week 1/day 1 and 
 mg 
administered 1 week later at week 2/day 8, then at 2 weeks interval at week 4, 
week 6, week 8, and week 10.   
Subsequent dosing will be at 
 mg every 2 weeks thereafter up to and including 
week 28.   
Test Group: 
Switching Group 
Switching group with adalimumab administered by SC injection using prefilled 
syringes at a dose of 
 mg (2 x 
 mg loading dose) on week 1/day 1 and 
 mg 
administered 1 week later at week 2/day 8, then at 2 weeks interval at week 4, 
week 6, week 8, and week 10.   
• 
At week 12, subjects will be switched to ABP 501 and administered 
ABP 501 
 mg SC on weeks 12 and 14.   
• 
At week 16, subjects will be switched back to adalimumab and 
administered adalimumab 
 mg SC on weeks 16 and 18.   
• 
At week 20, subjects will then be switched to ABP 501 and administered 
ABP 501 
 mg SC on weeks 20, 22, 24, 26, and with last dose on 
week 28.   
SC = subcutaneous 
Sites and Regions: 
This study is planned to be conducted globally at sites including but not limited to North America 
and Europe.   
Data Monitoring Committee: For details on the Data Monitoring Committee, refer to 
Section 10.1.3, Appendix 1.   
Statistical Analysis: 
The primary analysis of the primary PK endpoints, area under the curve from time 0 over the 
dosing interval (AUCtau) and maximum concentration (Cmax), between weeks 28 and 30 will be 
performed based on the PK Parameter Analysis Set (consisting of all subjects who are 
randomized and received all assigned doses post-randomization and who have an evaluable 
ABP 501 or adalimumab serum concentration-time profile between weeks 28 and 30), according 
to the actual treatment groups (switching group versus continued-use group).  The point 
estimates and 90% confidence intervals (CIs) for the GMRs between ABP 501 and adalimumab 
for AUCtau and Cmax between weeks 28 and 30 will be estimated using an analysis of covariance 
(ANCOVA) model adjusting for stratification factors, weight, and PK trough concentration at the 
end of the lead-in period (week 12).  Prior to statistical modeling, the PK parameters will be 
logarithmically transformed (natural log).  Point estimates and 90% CIs for the mean difference 
in logarithmic PK parameters will be estimated from the ANCOVA model, which will then be 
transformed back to the original scale to obtain the point estimates and 90% CIs for GMR.  
AUCtau and Cmax of ABP 501 and adalimumab between weeks 28 and 30 will be listed by subject 

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 14 of 87 
 
and summarized descriptively by treatment group.  A sensitivity analysis of the primary PK 
endpoints will be conducted on the Per Protocol PK Parameter Analysis Set (consisting of all 
subjects from the PK Parameter Analysis Set who do not have an important protocol deviation 
that could affect the primary PK endpoints).  To establish the risk in terms of safety or 
diminished efficacy of switching is not greater than the risk of using the reference product 
without such switch, the 90% CI of GMRs of ABP 501 versus adalimumab for AUCtau and Cmax 
from the primary analysis should fall within the pre-specified similarity margin.   
The analyses of the secondary PK endpoints of time of maximum concentration (tmax) between 
weeks 28 and 30 and trough concentration (Ctrough) between weeks 14 and 28 will be based on 
the PK Parameter Analysis Set according to the actual treatment groups (switching group 
versus continued-use group).  tmax will be summarized descriptively by treatment group and 
Ctrough between weeks 14 and 28 will be summarized descriptively by visit and treatment group.  
The point estimates and 90% CIs for GMR for Ctrough between the two treatment groups will be 
estimated using an ANCOVA model adjusting for stratification factors, weight, and PK trough 
concentration at the end of the lead-in period (week 12).   
The analysis of the secondary efficacy endpoints will be based on the Per Protocol Efficacy 
Analysis Set (consisting of all subjects who are randomized and received all assigned doses 
post-randomization and who have not experienced an important protocol deviation that may 
affect the evaluation of the efficacy endpoints) according to the actual treatment groups 
(switching group versus continued-use group).  The point estimate and 90% CI of the mean 
difference in Psoriasis Area and Severity Index (PASI) percent improvement from day 1 at 
week 30 will be estimated from an ANCOVA model adjusting for the baseline PASI value and 
the stratification factors.  The point estimate and 90% CI of the risk differences in PASI 75, 
PASI 90 and PASI 100 response rates at week 30 will be estimated from a generalized linear 
model with an identity link adjusting for the stratification factors.  Missing data will be imputed by 
last observation carry forward method for PASI percent improvement from day 1 at week 30 and 
by non-responder imputation for PASI 75, PASI 90 and PASI 100 response rates at week 30.  In 
addition, the PASI percent improvement from day 1 at week 30 and the PASI 75, PASI 90 and 
PASI 100 response rates at week 30 will be summarized descriptively by treatment group.   
All reported adverse events will be categorized by system organ class and preferred term 
according to the Medical Dictionary for Regulatory Activities (latest version at the time of final 
analysis) dictionary and graded by Common Terminology Criteria for Adverse Events, version 

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 15 of 87 
 
4.03.  Safety analyses of the safety endpoints will be performed based on the Safety Analysis 
Set (consisting of all subjects who are randomized and receive any investigational product post 
randomization) according to the actual treatment received.  Treatment-emergent adverse events 
post randomization are defined as adverse events that start or worsen on or after the first dose 
of investigational product post randomization and prior to the EOS.  The numbers and 
percentages of subjects reporting treatment-emergent adverse events, serious adverse events 
and events of interests will be tabulated by treatment group.  The number and percent of 
subjects developing binding or neutralizing antidrug antibodies (ADA) in the subset of Safety 
Analysis Set who have never tested positive (ie, tested negative or no results) prior to the first 
dose of investigational product post randomization and have at least one ADA result post 
randomization will be tabulated descriptively by treatment group and by visit.   
In addition, safety analyses prior to randomization will be performed based on the Lead-in 
Treated Set (consisting of all enrolled subjects treated with at least 1 dose of investigational 
product during the lead-in period).  The number and percentage of subjects reporting treatment-
emergent adverse events, serious adverse events and events of interest while receiving 
adalimumab during the lead-in period will be summarized.  The number and percentage of 
subjects developing binding or neutralizing ADAs for adalimumab during the lead-in period will 
be summarized.  

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 16 of 87 
 
1.2 Schema 
Figure 1–1 
Study Schema 
 
D: day = N: number of subjects; PK = pharmacokinetics; Q2W = every other week; SC = subcutaneous; W: week 
 

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 17 of 87 
 
1.3 Schedule of Assessments 
Table 1-1. 
Schedule of Assessments 
 
Screen 
Baseline 
Week 
PK Endpoint Assessments 
Post Actual Week 28 Dose Date 
 
(+ 3 
days) 
(± 3 days) 
End of Study 
(± 3 days)a 
Study Visit 
 28 days Week 1/D
ay 1 
W2/ 
Day 8 4 6 8 10 12j 14 16 18 20 22 24 26 28b +1d +3d +4d +7d +11d +14d 
32 
Informed consent  
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Medical/medication history  
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Physical examination  
X 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
Height  
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Weight 
X 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
Vital signs  
X 
X 
X 
 
X 
 
 
X 
 
X 
 
X 
 
 
 
X 
 
 
 
 
 
X 
X 
Adverse events 
Xc 
X 
X 
X X X X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Concomitant meds 
X 
X 
X 
X X X X X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Disease assessments 
PASI/sPGA/affected BSA 
X 
X 
 
 
X 
 
 
Xj 
 
X 
 
X 
 
 
 
 
 
 
 
 
 
X 
 
Laboratory assessments 
TB Testingd 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chest radiographye 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
TB worksheetf 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Serology (HBsAg, HBcAb, HCV, 
HIV) 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Serum pregnancy test  
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Urine pregnancy test 
 
X 
 
 
X 
 
 
X 
 
 
 
X 
 
 
 
X 
 
 
 
 
 
 
X 
Hematology  
X 
X 
 
 
X 
 
 
X 
 
 
 
X 
 
 
 
 
 
 
 
 
 
 
X 
Chemistry 
X 
X 
 
 
X 
 
 
X 
 
 
 
X 
 
 
 
 
 
 
 
 
 
 
X 
Urinalysis 
X 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
Pharmacokinetic sampleh 
 
X 
 
 
X 
 
 
X 
 
X 
 
X 
 
 
 
Xg 
X 
X 
X 
X 
X 
X 
X 
Antidrug antibody sampleh 
 
X 
 
 
X 
 
 
X 
 
X 
 
X 
 
 
 
X 
 
 
 
 
 
X 
X 
Investigational product 
Randomization 
 
 
 
 
 
 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
IP administrationi 
 
X 
X 
X X X X X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
 
 
 
 
 

Product: ABP 501 
Clinical Study Protocol: 20200497 
Final 1.0 Date: 03 Jun 2021 
Page 18 of 87 
 
BSA = body surface area; CT = computed tomography; HBcAb = hepatitis B core antibody; HBsAg = hepatitis B surface antigen; HCV = hepatitis C virus; 
HIV = human immunodeficiency virus; IP = investigational product; MRI = magnetic resonance imaging; PASI = Psoriasis Area and Severity Index; 
PK = pharmacokinetics; PPD = purified protein derivative; sPGA = static Physician’s Global Assessment; TB = tuberculosis.   
a 
Subjects terminating early from the study should complete all procedures scheduled for EOS Visit (ie, week 32) within 28 days after withdrawal/discontinuation if possible.   
b 
Week 28 visit will have a window of ± 3 days.   
c 
Report serious adverse events that occur after signing informed consent form.  Nonserious adverse events are reported as medical history prior to enrollment.   
d 
A QuantiFERON TB/T-spot or local equivalent will be performed.  For the purposes of this study.  Additional TB tests could be performed during the course of the study at 
the discretion of the investigator and according to local practice. 
e 
Chest radiograph will include anterior/posterior or posterior/anterior and lateral views.  Historical films obtained or formal reports signed off by radiologist in the 3 months 
prior to screening are acceptable.  Chest X-ray may be substituted by a chest CT or chest MRI, if available within 3 months prior to screening. 
f 
Only for subjects with a positive tuberculosis test (ie, positive or indeterminate QuantiFERON, positive PPD).   
g 
Pharmacokinetic sample will be collected as close to the nominal time points as possible.  Study centers should strictly adhere to the tolerance windows outlined in the table 
below for week 28 through week 30 PK endpoint sample collection.   
h 
Pharmacokinetic and antidrug antibody samples should be drawn prior to investigational product administration at dosing visits (except 1 hour post week 28 dose 
pharmacokinetic sample).   
i 
ABP 501 or adalimumab will be administered after all other procedures are completed for each visit.  If the subject presents with an infection/adverse event at the dosing 
visit(s), the administration of investigational product may be delayed up to 5 days.  In the case of delayed or missed dose, subsequent doses should be administered 
according to the original schedule (ie, at the planned time point relative to first dose/day 1).  A minimum of 7 days must elapse between administrations of 2 doses.   
j 
Subjects achieving less than PASI 50 response at week 12 visit will be considered non-responders and will be discontinued from the study at week 12. Subjects unable to 
complete the week 12 visit will be discontinued from the study. These subjects will be asked to complete an End of Study Visit procedures.  
Table 1-2. 
Tolerance Windows for Pharmacokinetic Endpoint Sample Collection 
Study Visit 
Tolerance Windowsa 
Week 28 predose 
Within 3 hours prior to week 28 investigational product administration 
1 hour post week 28 dose 
± 15 minutes 
1 day post week 28 dose 
± 5 hours 
3 days post week 28 dose 
± 6 hours 
4 days post week 28 dose 
± 6 hours 
7 days post week 28 dose 
± 6 hours 
11 days post week 28 dose 
± 24 hours 
14 days post week 28 dose  
± 48 hours 
PK = pharmacokinetic(s). 
a. 
The week 28 visit and dose should be performed with a window of ± 3 days.  Subsequent visits are done in relation to the actual week 28 investigational 
product dose date (eg, for the 3 days post week 28 dose time point, the PK sample should be collected 3 days after the actual week 28 dose, with a 
collection window of ± 6 hours).   

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2 Introduction 
ABP 501 is Amgen’s biosimilar product to Humira® (adalimumab).  ABP 501 is approved in the 
United States (US) under brand name of AMJEVITA™ (adalimumab-atto) and 
approved/marketed in European Union and other countries, as AMGEVITA® (adalimumab). 
[AMGEVITA® Summary of Product Characteristics (SmPC), March 2020, AMJEVITA™ 
(adalimumab-atto) United States Prescribing Information (USPI), June 2019]. ABP 501 is 
approved as a 50 mg/mL formulation.  
Amgen is now developing a new ABP 501 high concentration (
 mg/mL) formulation (referred 
to in this protocol as ABP 501-HCF).  The dosage forms, route of administration (subcutaneous 
[SC]) and dosing regimens for ABP 501-HCF will be the same as those for the approved 
50 mg /mL formulation; 
 
  ABP 501-HCF has not been approved or marketed anywhere.  For specifics related to 
the minor differences in excipients between ABP 501 formulations and analytical comparability 
assessment please refer to the ABP 501 Investigator’s Brochure. 
Note that in this protocol the term “investigational product” refers to both, ABP 501-HCF or 
adalimumab (
 mg/mL approved formulation).  
2.1 Study Rationale 
This study is being conducted to support a demonstration that ABP 501 is interchangeable with 
adalimumab (US), as defined by the US Biologic Price Competition and Innovation Act of 2009 
(BPCI Act).  
US Food and Drug Administration (FDA) defines interchangeability to mean that “the biological 
product may be substituted for the reference product without the intervention of the health care 
provider who prescribed the reference product” (FDA Guidance for Industry: Biosimilars: 
Considerations in Demonstrating Interchangeability with a Reference Product 2019).  
The primary objective of this switching study is to demonstrate that the risk in terms of safety or 
diminished efficacy of switching between ABP 501 (a proposed interchangeable biosimilar 
product) and adalimumab (a reference product) is not greater than the risk of using adalimumab 
without such switch.  More specifically, the study aim is to demonstrate that the switching 
between adalimumab and ABP 501 does not result in differences in predefined key PK 

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parameters, when compared with continued use of adalimumab.  Immunogenicity, clinical 
efficacy and safety will be also assessed descriptively as secondary endpoints.  
The study will be conducted using the 
 mg/
 mL PFS presentation of adalimumab (sourced 
in the US) and the 
 mg/
 mL PFS presentation of ABP 501-HCF (currently under 
development).  
2.2 Background 
ABP 501 is Amgen’s biosimilar product to Humira® (adalimumab).  ABP 501 is a tumor necrosis 
factor (TNF) blocker (a recombinant human IgG1 monoclonal antibody) indicated for treatment 
of chronic inflammatory conditions that include rheumatoid arthritis, juvenile idiopathic arthritis, 
psoriatic arthritis ankylosing spondylitis, adult Crohn's disease and ulcerative colitis, plaque 
Psoriasis (Ps).  Please refer to prescribing information of the respective products (AMJEVITA™, 
AMGEVITA®). The new ABP 501-HCF (
 mg/mL) currently under development has no 
changes to the active substance, conditions of use, dosing regimen, or route of administration.  
The ABP 501-HCF contains 2 of the same excipients (sucrose and polysorbate 80) as the 
marketed ABP 501 but uses an 
 based formulation compared to an acetate based 
formulation used for ABP 501. Refer to ABP 501 Investigator’s Brochure for details and plans 
related to ABP 501- HCF. 
The 
 mg/mL concentration formulation is approved and marketed for the adalimumab (US) 
reference product. 
2.3  Benefit/Risk Assessment 
The doses (
 mg) and dose regimens of both investigational products proposed in this study 
are consistent with the ABP 501 and Humira® products prescribing information for patients with 
plaque Ps. Thus, the risks and benefits of ABP 501-HCF are expected to be similar to those of 
adalimumab (reference product).  More detailed information about the expected benefits, risks, 
and potential adverse reactions to ABP 501 can be found in the ABP 501 Investigator’s 
Brochure. 
 present in the new ABP 501-HCF, to be used in this study, is generally recognized 
as a naturally occurring substance that is safe for humans and the amount of 
 in the 
maximum ABP 501‑HCF dose is below what is currently approved for other marketed SC 
administered products.  No clinically meaningful differences in the safety or local, injection site 
tolerability of ABP 501‑HCF (
 mg/mL) compared with adalimumab (
 mg/mL formulation) 

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are expected. Of note, a risk assessment will be performed on an ongoing basis to evaluate the 
potential impact of coronavirus disease 2019 (COVID-19) on subjects.  Risk mitigation 
measures, including COVID-19 related precautions and procedures (including severe acute 
respiratory syndrome coronavirus 2 [SARSCoV2] testing/screening) will be implemented based 
on the prevailing situation during study conduct, at the investigator’s discretion and in 
accordance with local and institutional guidelines, as applicable. 
2.4 Overall Benefit: Risk Conclusion 
Considering the measures taken to minimize risk to subjects participating in this study, the 
potential risks identified in association with ABP 501-HCF, as well as switching between 
ABP 501-HCF and adalimumab (US), are justified by the anticipated benefits to subjects with 
moderate to severe Ps.  On the basis of the available nonclinical and clinical data, and prior 
knowledge of ABP 501 
 mg/
 mL and adalimumab 
 mg/
 mL and 
 mg/
 mL 
(Humira®), the risk-benefit profile of ABP 501 
 mg/
 mL (ABP 501-HCF) is judged 
acceptable for the proposed clinical study. 

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3 Objectives and Endpoints 
Table 3-1. 
Objectives and Endpoints 
Objectives 
Endpoints 
Primary Objective: 
Primary Endpoints: 
• 
To demonstrate similarity of PK in subjects after 
multiple switches between adalimumab and 
ABP 501, compared to subjects receiving 
continued-use of adalimumab. 
Pharmacokinetic parameters: 
• 
AUCtau between week 28 and week 30 
• 
Cmax between week 28 and week 30.   
Secondary Objective: 
Secondary Endpoints: 
• 
To assess the efficacy, safety, and immunogenicity 
in subjects after multiple switches between 
ABP 501 and adalimumab compared with subjects 
receiving continued-use of adalimumab.   
Pharmacokinetic related Endpoints: 
• 
tmax between week 28 and week 30.   
• 
Ctrough between week 14 and week 28.   
Efficacy related Endpoints: 
• 
PASI percent improvement from baseline (day 1) to 
week 30.   
• 
PASI 75 response at week 30.   
• 
PASI 90 response at week 30.   
• 
PASI 100 response at week 30.   
Safety related Endpoints: 
• 
Treatment-emergent adverse events and serious 
adverse events, post randomization.   
• 
Events of interest, post randomization.   
Immunogenicity-related Endpoints: 
• 
Incidence of ADAs, post randomization  
ADAs = antidrug antibodies; AUCtau = area under the curve from time 0 over the dosing interval; Cmax = maximum 
concentration; Ctroug =: trough concentration; PK = pharmacokinetic(s); PASI: Psoriasis Area and Severity Index; 
tmax = time of maximum concentration. 
 

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4 Study Design 
4.1 Overall Design 
This is a randomized, double-blind, phase 3 study in adult subjects with moderate to severe Ps.  
This study is planned to be conducted globally at study centers including but not limited to North 
America and Europe.   
The total duration of study participation for each subject will be about 36 weeks, with up to 
4 weeks for screening and approximately 32 weeks after the first investigational product 
administration.   
Table 4-1. 
Investigational Product Groups 
Reference Group 
Adalimumab 
Continued-use Group 
Continued-use of adalimumab administered by SC injection using prefilled 
syringes at a dose of 
 mg (2 x 
 mg loading dose) on week 1/day 1 and 
 mg 
administered 1 week later at week 2/day 8, then at 2 weeks interval at week 4, 
week 6, week 8, and week 10.   
Subsequent dosing will be at 
 mg every 2 weeks thereafter up to and including 
week 28.   
Test Group 
Switching Group 
Switching group with adalimumab administered by SC injection using prefilled 
syringes at a dose of 
 mg (2 x 
 mg loading dose) on week 1/day 1 and 
 mg 
administered 1 week later at week 2/day 8, then at 2 weeks interval at week 4, 
week 6, week 8, and week 10.   
• 
At week 12, subjects will be switched to ABP 501 and administered 
ABP 501 
 mg SC on weeks 12 and 14.   
• 
At week 16, subjects will be switched back to adalimumab and 
administered adalimumab 
 mg SC on weeks 16 and 18.   
• 
At week 20, subjects will then be switched to ABP 501 and administered 
ABP 501 
 mg SC on weeks 20, 22, 24, 26, and with last dose on 
week 28.   
SC = subcutaneous. 
The study is composed of two periods.  A lead-in period of treatment with adalimumab 
(weeks: 1 to 12) followed by a randomized two parallel arm period (weeks: 12 to 32).  Subjects 
will receive an initial 6 doses of adalimumab on day 1/week 1 (
 mg loading dose), 1 week 
later on day 8/week 2 (
 mg), then at 2 weeks interval on week 4, week 6, week 8, and 
week 10 (
 mg), administered subcutaneously (SC).  At week 12, subjects with Psoriasis Area 
and Severity Index (PASI) ≥ 50 (PASI 50) response will be randomized to either the 
continued-use group or switching group in a 1:1 ratio, stratified by geographic region and prior 
biologic use at baseline (week 1/day 1, yes vs. no).  Subjects achieving less than PASI 50 
response at week 12 visit will be considered non-responders and will be discontinued from the 
study at week 12.  These subjects will be asked to complete End of Study (EOS) Visit 
procedures.  Subjects randomized to the continued-use group will continue on adalimumab 

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Q2W with last dose at week 28.  Subjects randomized to the switching group will switch to 
ABP 501 Q2W at week 12 (dosed week 12 and week 14), then back to adalimumab Q2W at 
week 16 (dosed week 16 and week 18), and again to ABP 501 Q2W at week 20, (dosed 
week 20, week 22, week 24, week 26, and with last dose of ABP 501 at week 28).   
All enrolled subjects not randomized at week 12 will be considered lead-in failures and the 
lead-in failure reason will be documented.  
An EOS Visit will be conducted at week 32.   
4.2 Scientific Rationale for Study Design 
The current study is designed to demonstrate that the risk in terms of safety or diminished 
efficacy of switching between ABP 501 (a proposed interchangeable biosimilar product) and 
adalimumab (a reference product) is not greater than the risk of using adalimumab without such 
switch.   
A dedicated switching study approach has been selected, as outlined in the US FDA guidance 
(Guidance for Industry: Biosimilars: Considerations in Demonstrating Interchangeability with a 
Reference Product, May 2019).   
This study is designed to assess whether switching between adalimumab (reference product) 
and ABP 501-HCF (three switches with the last switch from adalimumab to ABP 501-HCF) will 
result in differences in PK or immunogenicity profiles, when compared to continued therapy with 
adalimumab (reference product).  The Cmax and AUCtau at the end of multiple switching between 
investigational products were chosen as co-primary PK study endpoints. 
The FDA guidance provides recommendations to conduct clinical switching studies in relevant 
patient population rather than in healthy volunteers.  Population of subjects with moderate to 
severe plaque psoriasis was thus selected for this study, as it offers a sensitive model to detect 
potential differences with regard to immunogenicity, PK, safety, and efficacy (Guidance for 
Industry: Biosimilars: Considerations in Demonstrating Interchangeability with a Reference 
Product, May 2019) in a repeat dose setting.   
4.2.1 Subject Input into Design 
Not applicable.   

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4.3 Justification for Dose 
The doses used in this study include both the 
 mg initial loading dose, followed by 
 mg 
every other week starting one week after initial dose and the 
 mg Q2W dose, all of which are 
used as per the label (AMJEVITA™ USPI, June 2019).  See Section 6.7 for dose modifications.   
4.4 End of Study Definition 
A subject is considered to have completed the study if he/she has completed all phases of the 
study including an EOS Visit or the last scheduled procedure shown in the Schedule of 
Assessments (Table 1-1).  An EOS visit will be performed for subjects who are prematurely 
discontinued.  All procedures listed under EOS visit must be completed for subjects who are 
prematurely discontinued. 
The EOS is defined as the date of the last visit of the last subject in the study or last scheduled 
procedure shown in the Schedule of Assessments (Table 1-1) for the last subject in the study 
globally.   
5 Study Population 
The study population will consist of subjects with moderate to severe Ps (See Section 4.2 for 
details on rationale).  Subjects (or legally acceptable representative) must be able to provide 
written consent and subjects must meet all the inclusion criteria and none of the exclusion 
criteria.   
Approximately 414 subjects will be enrolled.  Randomization will be stratified by prior biologic 
use for psoriasis at baseline (week 1/day 1, yes vs. no) and geographic region.  Subjects with 
prior biologic use for psoriasis will be capped at 50% of the total enrolled subjects.   
The number of subjects enrolled may be adjusted during the study with the actual lead-in failure 
rate seen to ensure approximately 342 subjects will be randomized at week 12.   
5.1 Inclusion Criteria 
Subjects cannot be enrolled before all the inclusion criteria (including test results) are confirmed.  
Subjects are eligible to be included in the study only if all of the following criteria apply: 
1. Subject is male or female and is ≥ 18 and ≤ 75 years of age inclusive, at the time of 
enrollment.   

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2. Subject has moderate to severe Ps (with or without psoriatic arthritis) for at least 
6 months and has stable disease for at least 2 months (eg, no morphology changes or 
significant flares of disease activity in the opinion of the investigator).   
3. Subject has a score of PASI ≥ 12, involvement of ≥ 10% body surface area (BSA) and 
static Physician’s Global Assessment (sPGA) ≥ 3 at screening and at baseline.   
4. Subject is a candidate for phototherapy or systemic therapy, when other systemic 
therapies are clinically less appropriate.   
5. Female subject (except if postmenopausal or surgically sterile, definitions outlined in 
Section 10.2): a negative serum pregnancy test during screening and a negative urine 
pregnancy test at baseline.   
6. Subject or legally acceptable representative is capable of giving signed Institutional 
Review Board (IRB)/Independent Ethics Committee (IEC) informed consent.   
7. Subject has no known history of latent or active tuberculosis.  Subject must meet any 1 of 
the following 3 criteria: 
• 
Subject has a negative test for tuberculosis during screening, defined as either: 
o Negative purified protein derivative (PPD); < 5 mm of induration at 
48 hours to 72 hours after test is placed, or 
o Negative QuantiFERON®/T-spot® test.   
• 
Subject with a positive PPD test and a history of Bacillus Calmette Guerin (BCG) 
vaccination is allowed with a negative QuantiFERON®/T-spot® test.   
• 
Subject with a positive PPD test (without a history of BCG vaccination) or subject 
with a positive or indeterminate QuantiFERON®/T-spot® test is allowed if he/she 
has all of the following: 
o No symptoms per tuberculosis worksheet provided by the sponsor, Amgen 
Inc.   
o Documented history of adequate prophylaxis initiation prior to receiving 
investigational product in accordance with local recommendations.   
o No known exposure to a case of active tuberculosis after most recent 
prophylaxis.   
o No evidence of active tuberculosis on chest radiograph taken within 
3 months prior to the first dose of investigational product and read by a 
qualified radiologist/specialist.   

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5.2 Exclusion Criteria 
Subjects are excluded from the study if any of the following criteria apply: 
Skin Disease Related Conditions 
1. Subject has erythrodermic psoriasis, pustular psoriasis, guttate psoriasis, medication-
induced psoriasis, or other skin conditions at the time of screening (eg, eczema) that would 
interfere with evaluations of the effect of investigational product of psoriasis.   
Other Medical Conditions 
2. Subject has a planned major surgical intervention during the duration of the study.   
3. Subject has an active infection or history of infections, as follows: 
• 
Any active infection for which systemic anti-infective therapy was used within 
28 days prior to enrollment.   
• 
A serious infection, defined as requiring hospitalization or IV anti--infective 
therapy within 8 weeks prior to enrollment.   
• 
Opportunistic, recurrent or chronic infections, or other active (including invasive 
fungal or mycobacterial) infection that, in the opinion of the investigator, might 
cause this study to be detrimental to the subject.   
4. Subject has known history of human immunodeficiency virus (HIV) infection or has positive 
HIV serology at screening.   
5. Subject has hepatitis B surface antigen (HBsAg), is positive for hepatitis B core 
antibody (HBcAb) or has hepatitis C virus antibody positivity at screening.   
6. Subject has uncontrolled, clinically significant systemic disease including, but not limited to 
metabolic disturbances including, uncontrolled diabetes mellitus, cardiovascular, renal, liver, 
pulmonary, gastrointestinal, hematologic, psychiatric disease, or hypertension.   
7. Subject has known malignancy within the previous 5 years (except treated or considered 
cured cutaneous squamous or basal cell carcinoma, in situ cervical cancer, or in situ breast 
ductal carcinoma).   
8. Subject has active neurological disease, such as multiple sclerosis, -Guillain-Barre 
syndrome, optic neuritis, transverse myelitis, or history of neurologic symptoms suggestive 
of central nervous system demyelinating disease.   
9. Subject has moderate to severe heart failure (New York Heart Association class III/IV), 
history of significant cardiac arrhythmia and/or cardiac hospitalization within 3 months prior 
to enrollment.   

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10. Subject has known hypersensitivity to the investigational products or to any of the 
excipients.   
11. Subject has any concurrent medical condition, including hypersensitivity to any biologic 
medication, that, in the opinion of the investigator, could cause this study to be detrimental 
to the subject.   
Laboratory Abnormalities 
12. Subject has laboratory abnormalities at screening, including any of the following: 
• 
Hemoglobin < 9 g/dL.   
• 
Platelet count < 100,000/mm3.   
• 
White blood cell count < 3,000 cells/mm3.   
• 
Aspartate aminotransferase and/or alanine aminotransferase ≥ 2.0 × the upper 
limit of normal.   
• 
Creatinine clearance < 50 mL/min (measured by Cockcroft-Gault formula).   
• 
Any other laboratory abnormality which, in the opinion of the investigator, will 
prevent the subject from completing the study or will interfere with the 
interpretation of the study results.   
Washouts and Non-permitted Drugs 
13. Subject has previously received adalimumab or a biosimilar of adalimumab (approved or 
investigational). 
14. Subject has received biologic treatment for psoriasis within the previous month or 5 drug 
half-lives (whichever is longer) prior to enrollment.   
15. Subject has received any investigational agents within the previous month or 5 half-lives 
(whichever is longer) prior to enrollment.   
16. Subject has received nonbiologic systemic psoriasis therapy within 4 weeks prior to 
enrollment (including, but not limited to, apremilast [within 2 weeks prior to enrollment], oral 
retinoids, methotrexate, cyclosporine, systemically administered calcineurin inhibitors, 
azathioprine, thioguanine, hydroxyurea, fumarates, mycophenolate mofetil, Janus kinase 
inhibitors, or oral or parenteral corticosteroids including intramuscular or intraarticular 
administration, exception: ophthalmic, otic, nasal, or inhaled corticosteroids within 
recommended doses is permitted).   
17. Subject has received ultraviolet (UV) A phototherapy (with or without psoralen) or excimer 
laser within 4 weeks prior to enrollment, or UV B phototherapy within 2 weeks prior to 
enrollment.   

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18. Subject has received topical psoriasis treatment within 2 weeks prior to enrollment 
(exception: upper mid-strength to least potent [class III to VII] topical steroids permitted on 
the palms, soles, face, and intertriginous areas; bland emollients [without urea or α or 
βhydroxy acids]).   
19. Subject has received live viral or live bacterial vaccination within 4 weeks prior to enrollment 
or intends to receive live viral or live bacterial vaccine at any time during the study.   
20. Subject has received or plans to receive other investigational procedures or device within 4 
weeks prior to enrollment or during the course of the study.   
21. Subject has prior use of two or more biologics for treatment of psoriasis.   
General 
22. Female of childbearing potential* who is sexually active with male partner and is unwilling to 
use an effective method of birth control.  Effective birth control is defined as agreement to 
consistently practice an effective and accepted method of contraception† throughout the 
duration of the study and for 5 months after last dose of study drug.  Female of childbearing 
potential must also agree not to donate eggs (ova, oocytes for the purpose of assisted 
reproduction) for at least 5 months after receiving the last dose of the investigational 
product. 
*† Definitions of childbearing potential, menopause, surgical sterility and acceptable contraception 
methods are outlined in Section 10.2, Appendix 2.  The methods should be consistent with country or 
local regulations for subjects participating in clinical trials.   
23. Subject has evidence (as assessed by the Investigator or designee using clinical judgment) 
of active substance abuse within 24 weeks prior to screening that may impact subject’s 
ability to participate in the study.   
24. Female subject who is pregnant or breastfeeding or planning to become pregnant while 
participating in the study and for at least 5 months after the last dose of investigational 
product.   
25. Subject is not likely to comply with all required study procedures, or not available for 
protocol-required study visits or procedures (including multiple PK blood draws between 
weeks 28 and 30), to the best of the subject and investigator knowledge. 
26. Subject has any physical or psychiatric disorder that, in the opinion of the investigator, may 
compromise the ability of the subject to give informed consent and/or to comply with all the 
required study procedures.   

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5.3 Subject Enrollment 
Before subjects begin participation in any study specific activities/procedures, Amgen requires a 
copy of the site’s written IRB/IEC approval of the protocol, informed consent form (ICF), and all 
other subject information and/or recruitment material.   
The subject or legally acceptable representative must personally sign and date the IRB/IEC and 
Amgen approved ICF before commencement of study specific procedures.   
A subject is considered enrolled when the investigator decides that the subject has met all 
eligibility criteria and has been enrolled in the Interactive Web/Voice Response System (IXRS).  
The investigator is to document this eligibility decision and date in the subject’s medical record.   
Each subject will have a unique subject identification number obtained from the IXRS.  This will 
be assigned at screening.  The unique 11-digit subject identification number will be assigned in 
sequential order for each site in the format “497XXXXX###,” where “497XXXXX” refers to the 
site number and “###” refers to the sequential subject ordering as each subject at a site is 
entered into the IXRS (eg, 49712345001).  This number will be used to identify the subject 
throughout the clinical study and must be used on all study documentation related to that 
subject.  The investigator will keep a record (the subject screening log) that includes limited 
information (such as date of screening) about the potential candidates for subjects who entered 
screening.   
If a subject withdraws from study participation, his/her unique identification number(s) cannot be 
re-used for another subject.   
The subject identification number must remain constant throughout the entire clinical study; it 
must not be changed after initial assignment, including if a subject is rescreened.  This number 
will not necessarily be the same as the randomization number assigned for the study.   
5.4 Lifestyle Considerations 
5.4.1 Meals and Dietary Restrictions 
Not applicable.   
5.4.2 Caffeine, Alcohol, and Tobacco 
Not applicable.   

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5.4.3 Activity 
Subjects should avoid prolonged sun exposure and not to use tanning booths or other UV light 
sources during the study.   
5.4.4 Coronavirus Disease 2019 Considerations 
Study centers and subjects will follow local and institutional guidelines, as applicable, for the 
prevention of COVID-19 infection including COVID vaccination.  In the event that a subject 
experience any signs/symptoms of COVID-19, the subject should promptly notify the 
investigator.   
5.4.5 Coronavirus Disease 2019 Vaccination Considerations 
The currently authorized COVID-19 vaccines are not live vaccines, therefore can be safely 
administered to immunocompromised people.  While COVID-19 vaccines are not prohibited by 
the study protocol, given the nature of investigational products, it is important to have a 
conversation with study subject to ensure their understanding that, their immune response to 
the COVID-19 vaccine and the efficacy of the vaccine may be potentially impacted (reduced), 
while they receive an investigational product in this study.  Based on general best practices for 
vaccination of immunocompromised people (including individuals on immunosuppressive 
therapies, such as investigational products used in this study), it is recommended that the 
course of COVID-19 vaccinations is completed at least 2 weeks before study enrollment, or as 
per local guidance. 
5.5 Screen Failures 
Screen failures are defined as subjects who consent to participate in the clinical study but are 
not subsequently enrolled to the study.  A minimal set of screen failure information is required to 
ensure transparent reporting of screen failure subjects to meet the Consolidated Standards of 
Reporting Trials publishing requirements and to respond to queries from regulatory authorities.  
Minimal information includes demography, reason for screen failure (eg, eligibility requirements 
failed), and any serious adverse events.  Data for subjects who have screen failed will not be 
entered in the eCRF.   
If a subject has not met all eligibility criteria at the end of the screening period, the subject will 
be registered as a screen failure.  Individuals who do not meet the criteria for participation in this 
study (screen failure) may be rescreened.  Rescreened subjects should be assigned the same 

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subject identification number as for the initial screening.  Laboratory assessments used to 
determine subject eligibility may be repeated during the screening period before the subject is 
considered a screen failure.  Screen failed subjects may be rescreened up to 2 times at the 
investigator’s discretion (ie, a total of 3 screens including initial screening).  If screening 
procedures cannot be completed within 28 days before day 1, the subject will be considered a 
screen failure but may be eligible for rescreening.  These subjects can be rescreened under the 
same ICF if rescreening and enrollment occurs within 30 days of initial consent date.  If it is 
longer than 30 days from the initial consent date, the subject will need to be re-consented and 
all screening procedures need to be repeated.   
6 Investigational Product 
Investigational product is defined as any investigational intervention(s), marketed product(s), 
placebo, or medical device(s) intended to be administered to a study subject according to the 
study protocol. 
The investigator must ensure that the investigational product will be used only in accordance 
with the protocol.  Study treatments and investigational product are described in Table 6-1.   
6.1 Investigational Products Administered 
Table 6-1. 
Investigational Product(s) Administered 
Intervention Name 
ABP 501-HCF 
Adalimumab 
Type 
Biologic 
Biologic 
Dosage Formulation 
Liquid suspension 
Liquid suspension 
Unit Dose Strength(s) 
 mg/
 mL solution in a single dose 
prefilled syringe (
 mg/mL) 
 mg/
 mL solution in a single dose 
prefilled syringe (
 mg/mL) 
Dosage Level(s) 
 mg 
 mg for Day 1/Week 1 (initial loading 
dose) 
 mg for subsequent doses 
Route of Administration 
SC injection 
SC injection 
Use 
Experimental 
Active comparator 
IMP and NIMP 
IMP 
IMP 
Sourcing 
Provided centrally by the sponsor 
Provided centrally by the sponsor 

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Intervention Name 
ABP 501-HCF 
Adalimumab 
Dosing Instructions 
Subjects in the switching group will be 
administered ABP 501 on weeks 12, 
14, 20, 22, 24, 26, and 28.   
Subjects in the switching group will be 
administered adalimumab on 
week 1/day 1, and week 2/day 8 
week 2, and weeks 4, 6, 8, 10, 16, and 
18.   
Subjects in the continued-use group 
will be administered adalimumab on 
week 1/day 1, week 2/day 8, week 4, 
week 6, week 8, week 10, and Q2W 
thereafter up to and including week 28.   
Packaging and Labeling 
Investigational product will be provided 
in a prefilled syringe.  Each prefilled 
syringe will be labeled as required per 
country requirement.   
Investigational product will be provided 
in a prefilled syringe.  Each prefilled 
syringe will be labeled as required per 
country requirement.   
IMP =: investigational medicinal product; NIMP = non-investigational medicinal product; Q2W = every 2 weeks; 
SC = subcutaneous. 
6.1.1 ABP 501 Dosage Form 
ABP 501 is a recombinant fully human IgGκ monoclonal antibody produced by recombinant 
deoxyribonucleic acid (DNA) technology and is produced in a glyco-engineered Chinese 
hamster ovary (CHO) cell line.  ABP 501 is purified by processes that include specific viral 
inactivation and filtration steps.  ABP 501 and adalimumab have the same amino acid 
sequence.   
AMJEVITA™ (adalimumab‑atto, ABP 501) is a sterile, preservative‑free solution with a pH of 
5.2 for SC administration.  ABP 501‑HCF will be used for this study and contains 
 mg/mL 
adalimumab‑atto formulated with 
 mM 
% (w/v) sucrose, 0.1% (w/v) polysorbate 
80, at pH 5.2 (Table 6-1).  See the Investigator’s Brochure for additional details.   
ABP 501 is supplied in 
 mg/
 mL single dose of prefilled syringe. 
6.1.2 Adalimumab Dosage Form 
Adalimumab is an anti-TNF α monoclonal antibody which is produced by recombinant DNA 
technology, in a CHO cell expression system and purified by a suitable process.   
Adalimumab is supplied in 
 mg/
 mL single dose of prefilled syringe.   
6.2 Preparation, Handling, Storage, and Accountability 
Investigational product should be stored protected from light and according to the storage and 
expiration information provided on the label (where required) that is affixed to the package 
containing the investigational product.  The prefilled syringe should be stored in a secured 

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refrigerator (2°to 8°C) and monitored (manual or automated) in accordance with the labeled 
storage conditions and country--specific regulations, with access limited to the unblinded site 
staff.  Investigational product should not be frozen.  The unblinded pharmacist or designee must 
maintain documentation to confirm appropriate temperature conditions have been maintained 
during transit and storage at site for all investigational product received and any discrepancies 
are reported and resolved before use of the investigational product.   
The prefilled syringe should be checked for cracks or damage that may occur during transport.  
Damaged product should not be administered and should be returned to Amgen or its designee.   
Detailed information regarding the labeling, packaging, storage, preparation, and administration 
of each investigational product is to be provided separately in the Pharmacy Manual.   
All supplies of investigational product will be accounted for in accordance with GCP guidelines.  
The unblinded pharmacist, or designee should maintain accurate records of the disposition of all 
investigational product supplies received during the study.  These records should include the 
amounts and dates clinical drug supplies were received and returned to Amgen or its designee.  
If errors or damages in the clinical drug supply shipments occur, the unblinded pharmacist or 
designee should contact Amgen or its designee immediately.  Copies of the investigational 
product accountability records will be provided by each site for inclusion in the Trial Master 
File (TMF).  The unblinded clinical research associate (CRA) will periodically check the supplies 
of investigational product held at the site to verify accountability of all medication used.   
The unblinded site staff will administer investigational product only to the identified subjects of 
this study, according to the procedures described in this study protocol.  After the EOS, all 
unused investigational product and all investigational product containers should be destroyed 
on-site (if approved by the sponsor or designee) or returned to Amgen or its designee for 
destruction.  In either instance, complete documentation will be returned to the sponsor or 
designee.  Further guidance and information for the final disposition of unused investigational 
product are provided in the Pharmacy Manual.  The investigational product resupply will be 
managed by the IXRS.   
6.3 Investigational Product Complaints 
An investigational product complaint is any written, electronic, or oral communication that 
alleges deficiencies related to the identity, quality, durability, reliability, safety, effectiveness, or 

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performance of a drug(s) or device(s) after it is released for distribution to market or clinic by 
either Amgen or by distributors and partners for whom Amgen manufactures the material.   
Any investigational product complaint(s) associated with ABP 501 or adalimumab supplied by 
Amgen are to be reported according to the instructions provided in the Pharmacy Manual.  Any 
investigational product complaints associated with an adverse event are to be reported as per 
adverse event reporting guidelines.   
6.4 Measures to Minimize Bias: Blinding and Randomization 
The investigational product containers are largely matching for ABP 501 and adalimumab; 
however, to ascertain the blind is being maintained, the investigational product (ABP 501 or 
adalimumab) will be handled by an unblinded pharmacist or designee and will be administered 
to subjects by an unblinded, designated study nurse or designee.  The subjects, the sponsor 
(Amgen Inc.), designated CRO personnel, and other study center staff will be fully blinded to the 
investigational product allocation for each subject.  Randomization data will be kept strictly 
confidential, filed securely by the sponsor (or designee), and accessible only to authorized 
persons per sponsor’s (or designee’s) standard operating procedures until the time of 
unblinding.  Select CRO staff (eg, unblinded clinical research associates) who will not be 
involved in the monitoring or the daily operations of the study will be unblinded to subject 
investigational product allocation to perform investigational product accountability.  For details 
on the emergency procedure for unblinding of individual subjects please refer to the 
Section 6.4.1. 
6.4.1 Blinding 
The study is double-blind; therefore, the investigators, study personnel including the sponsor 
and CRO study team (with the exception of the unblinded site staff (see Section 6.4), Data 
Monitoring Committee [DMC], Parexel staff supporting DMC activities and randomization list 
activities, and unblinded Parexel staff supporting drug accountability activities) and the study 
subjects will remain blinded to treatment allocation.   
Randomization data will be kept strictly confidential, accessible only to authorized staff and the 
DMC until the time of unblinding.  Authorized staff includes the randomization statistician, who 
will store the master randomization list in a secure system, an unblinded statistician, and 
unblinded programmers, who will provide the DMC with unblinded data for review, as and when 

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required, in accordance with the procedures described in the DMC Charter.  All authorized 
unblinded staff must be documented.   
ABP 501 and adalimumab will be coded and labeled in a manner that protects blinding.   
Unblinding is only allowed in the case of an emergency, when knowledge of the investigational 
product is essential for the clinical management of the subject.  The investigator must make 
every effort to contact the sponsor or designee’s medical monitor prior to breaking the blind and 
must contact the sponsor or designee within 1 working day after the event, without revealing to 
the sponsor (or clinical research organization [CRO]) the results of the code break, except to the 
designated global safety representative.   
Emergency unblinding will be organized through the IXRS.  The investigator must record the 
date of unblinding and the reason.  All unblinding must be adequately documented.   
If a serious adverse event is reported, the designated global safety representative may unblind 
the treatment assignment for the individual subject through IXRS in order to meet regulatory 
reporting requirements.  Authorized staff will be provided with a unique Personal Identification 
Number (PIN) to access the IXRS to obtain blinding information.  The PIN is unique to the 
individual and must not be shared.   
6.4.2 Randomization 
At randomization, randomization numbers will be assigned to each subject by the IXRS.  The 
site will contact the IXRS at week 12 to receive a unique subject randomization number in order 
to randomize the subject centrally to either the switching group or continued-use group in a 1:1 
manner.  Randomization will be stratified by prior biologic use for psoriasis at baseline 
(week 1/day 1, yes vs. no) and geographic region.  All enrolled subjects not randomized at 
week 12 will be considered lead-in failures and the lead-in failure reason will be documented.   
In the event of a quality assurance (QA) audit, the auditor(s) will be allowed access to unblinded 
investigational product records to verify that randomization/dispensing has been done 
accurately.   
6.5 Investigational Product Compliance 
Records of investigational product used and intervals between visits will be kept during the 
study.  Drug accountability will be noted by the unblinded CRA during site visits and at the 

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completion of the study.  The study treatment should be dispensed by a qualified unblinded 
individual under the investigator’s supervision.  An upto date treatment inventory/dispensing 
record must be maintained.   
6.6 Concomitant Therapy 
6.6.1 Prohibited Treatments 
• 
Non study use of adalimumab, or a biosimilar of adalimumab, are prohibited 
(exclusion criterion 13).   
• 
Any biologic treatment for psoriasis, or any experimental (biological or 
nonbiological) therapy (within or outside of a clinical study), except for 
investigational product, for subjects are prohibited (exclusion criteria 13 and 15).   
• 
Treatments (exclusion criterion 16) which include nonbiologic systemic psoriasis 
therapy (including but not limited to apremilast [within 2 weeks prior to enrollment] 
oral retinoids, methotrexate, cyclosporine, systemically administered calcineurin 
inhibitors, azathioprine, thioguanine, hydroxyurea, fumarates, mycophenolate 
mofetil, Janus kinase inhibitors, or oral or parenteral corticosteroids including 
intramuscular or intraarticular administration [exception: ophthalmic, otic, nasal, or 
inhaled corticosteroids within recommended doses is permitted]).   
• 
Any other non study treatment for psoriasis, including UVA or UVB phototherapy 
and excimer laser (exclusion criterion 17) and topical therapies for psoriasis 
(except for those specifically allowed exclusion criterion 18) are prohibited.   
• 
Live viral or live bacterial vaccination (exclusion criterion 19).   
6.6.2 Prior and Concomitant Therapy 
Prohibited treatments are described in Section 6.6.1.   
Any other treatment (not explicitly excluded) which is considered necessary for the subject’s 
welfare may be given at the discretion of the investigator.  Allowed treatments include: 
• 
Bland moisturizers/emollients (without urea or α- or β-hydroxy acids) are allowed, 
as needed, during the study.   
• 
Upper mid-strength to least potent (class III to VII) topical steroids are permitted 
only on the palms, soles, face, and intertriginous areas.   

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• 
Otic, nasal, ophthalmic, or inhaled corticosteroids are not considered “systemic 
immunomodulating treatments” and are allowed during the study.   
At screening, prior medication and COVID vaccination history will be documented.   
Any vaccine or medication (including over-the-counter or prescription medicines, vitamins, 
and/or herbal supplements) that the subject is receiving at the time of enrollment or receives 
during the study must be recorded.   
The medical monitor should be contacted if there are any questions regarding prior or 
concomitant therapy.   
All subjects who discontinue investigational product should be offered alternative treatment, if 
applicable.  Treatment should be given according to normal clinical practice after the EOS Visit.   
6.7 Dose Modification 
There are no dose modifications for investigational products (ABP 501 or adalimumab) in this 
study.   
If the subject presents with a serious infection at the dosing visit(s), the administration of 
investigational product may be delayed (up to 5 days); and subjects with serious infections need 
to be monitored closely and investigational product should not be administered until the infection 
resolves.   
In the case of delayed or missed dose for any reason, subsequent doses should be 
administered according to the original schedule (ie, at the planned time point relative to first 
dose) investigational product dose(s).   
Any toxicities associated or possibly associated with investigational product treatment should be 
managed according to standard medical practice.  A summary of expected adverse drug 
reactions is provided in the Investigator’s Brochure.  Adalimumab has a terminal -half-life of 
approximately 14 days, therefore discontinuation results in slow elimination over several months 
and will have no immediate effect.   
If unmanageable toxicity due to investigational product occurs at any time during the study, 
treatment with the investigational product should be discontinued.   

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6.8 Intervention After the End of the Study 
After completing dosing with investigational product at week 28 and the EOS Visit at week 32, 
subjects will have completed the study.  ABP 501 or adalimumab will not be provided for post 
study use.   
 
 

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7 Discontinuation of Investigational Product and Subject 
Discontinuation 
Subjects have the right to withdraw from treatment with investigational product, protocol 
procedures, or the study completely at any time and for any reason without prejudice to their 
future medical care by the physician or at the institution.   
7.1 Discontinuation of Investigational Product 
Subjects (or a legally acceptable representative) can decline to continue receiving 
investigational product or procedures at any time during the study but continue participation in 
the study.  If this occurs, the investigator is to discuss with the subject the appropriate 
processes for discontinuation from investigational product and must discuss with the subject the 
possibilities for continuation of the Schedule of Assessments (Table 1-1) including different 
options of follow-up (eg, in person, by phone/mail, through family/friends, in 
correspondence/communication with other treating physicians, from the review of medical 
records) and collection of data, including adverse events, and must document this decision in 
the subject’s medical records.  Subjects who have discontinued investigational product and/or 
other protocol required therapies or procedures should not be automatically removed from the 
study.  Whenever safe and feasible, it is recommended that these subjects remain in the study 
to ensure safety surveillance and/or collection of efficacy data, where possible.  Reasons for 
early removal from -protocol-required investigational product(s) or procedural assessments may 
include: 
• 
Decision by sponsor  
• 
Lost to follow-up  
• 
Death  
• 
Adverse event  
• 
Subject request  
• 
Protocol deviation  
• 
Noncompliance  
• 
Pregnancy  

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7.2 Subject Discontinuation/Withdrawal from the Study 
Participation in the study is strictly voluntary.  Subjects have the right to withdraw from the study 
by his/her own request at any time and for any reason without any reprisal, and without 
prejudice to future medical care by the physician or institution.   
Subjects unable to complete the week 12 visit will be discontinued from the study.  However, 
subjects should return and complete EOS visit procedures.  The lead-in period will occur from 
day 1 until randomization at week 12.  All enrolled subjects not randomized at week 12 will be 
considered lead-in failures and the lead-in failure reason will be documented.  Subjects 
terminating early from the study should complete all procedures scheduled for EOS Visit 
(ie, week 32) within 28 days after withdrawal/discontinuation if possible.  Non-responders 
(defined as subjects achieving less than PASI 50 response at week 12 visit) will be discontinued 
from the study at week 12. These subjects will be asked to complete EOS Visit procedures.  
Withdrawal of consent for a study means that the subject does not wish to receive further 
protocol required therapies or procedures, and the subject does not wish to or is unable to 
continue further study participation.  Subject data up to withdrawal of consent will be included in 
the analysis of the study, and where permitted, publicly available data can be included after 
withdrawal of consent.  The investigator is to discuss with the subject appropriate procedures for 
withdrawal from the study and must document the subject’s decision to withdraw in the subject’s 
medical records.  If the subject withdraws consent for disclosure of future information, the 
sponsor may retain and continue to use any data collected before such a withdrawal of consent.  
If a subject withdraws from the study, he/she may request destruction of any samples taken and 
not tested, and the investigator must document this in the study center study records and notify 
the sponsor or designee.  Although a subject is not obliged to give his/her reason(s) for 
withdrawing prematurely from a study, the investigator should make a reasonable effort to 
ascertain the reason(s), while fully respecting the subject's rights.  Subjects who are withdrawn 
will not be replaced.  Subjects who prematurely discontinue from the study cannot subsequently 
rejoin the study.   
A subject may be discontinued from the study at any time at the discretion of the investigator for 
safety, behavioral, or administrative reasons, including, but not limited to: 
• 
Requirement for alternative therapy per the investigator’s determination 

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• 
The subject develops a malignancy (exception: subjects may be allowed to 
continue if they develop no more than 2 non-melanoma skin cancers during the 
study) 
• 
Adverse events or serious adverse events 
• 
Any laboratory abnormalities that in the judgment of the investigator, taking into 
consideration the subject’s overall status, prevents the subject from continuing 
participation in the study 
• 
Any other reason relating to the subject's safety or integrity of the study data 
• 
Noncompliance with study procedures 
• 
Withdrawal of consent from the study 
• 
Lost to follow-up 
• 
Decision by sponsor/investigator 
• 
Death 
Refer to the Schedule of Assessments (Table 1-1) for data to be collected at the time of study 
discontinuation and evaluations that need to be completed.   
If a subject withdraws or is discontinued from the study, the CRA will be informed immediately.   
7.3 Loss of Subjects to Follow-up 
A subject will be considered lost to follow-up if he or she repeatedly fails to return for scheduled 
visits and is unable to be contacted by the study site.   
The following actions must be taken if a subject fails to return to the clinic for a required study 
visit: 
• 
The site must attempt to contact the subject and reschedule the missed visit as 
soon as possible (and within the visit window, where one is defined) and counsel 
the subject on the importance of maintaining the assigned visit schedule and 
ascertain whether or not the subject wishes to and/or should continue in the 
study.   
• 
In cases in which the subject is deemed lost to follow-up, the investigator or 
designee must make every effort to regain contact with the subject (where 
possible, 3 telephone calls and, if necessary, a certified letter to the subject’s last 
known mailing address or local equivalent methods).  These contact attempts 
should be documented in the subject’s medical record. 

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• 
If the subject continues to be unreachable, he/she will be considered to have 
withdrawn from the study with a primary reason of lost to follow-up.   
8 Study Assessments and Procedures 
Study procedures and their timing are summarized in the Schedule of Assessments (Table 1-1).  
Protocol waivers or exemptions are not allowed.   
Immediate safety concerns should be discussed with the sponsor immediately upon occurrence 
or awareness to determine if the subject should continue or discontinue investigational product.   
Adherence to the study design requirements, including those specified in the Schedule of 
Assessments, is essential and required for study conduct.   
All screening evaluations must be completed and reviewed to confirm that potential subjects 
meet all eligibility criteria.  The investigator will maintain a screening log to record details of all 
subjects screened and to confirm eligibility or record reasons for screening failure, as 
applicable.   
Procedures conducted as part of the subject’s routine clinical management and obtained before 
signing of the ICF may be utilized for screening or baseline purposes provided the procedures 
met the protocol-specified criteria and were performed within the time frame defined in the 
Schedule of Assessments (Table 1-1).   
Repeat or unscheduled samples may be taken for safety reasons or for technical issues with the 
samples.   
Investigational product will be administered after all other procedures are completed for each 
dosing visit.   
Informed Consent 
Informed consent must be documented according to Section 10.1.2, Appendix 1.   
Eligibility Criteria 
All inclusion and exclusion criteria will be reviewed by the investigator or designee to ensure 
that the subject qualifies for the study.   

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Medical History 
A medical history will be obtained by the investigator or qualified designee.  The medical history 
will collect all active conditions and any prior conditions that the investigator considers to be 
clinically relevant.   
Prior and Concomitant Medications Review 
The investigator or qualified designee will review prior medication use and record prior 
medications taken by the subject.   
The investigator or qualified designee will record medication, if any, taken by the subject during 
the study through the last visit.   
Demographic Data 
Demographic data, including (where permitted), date of birth/age, sex, race, and ethnicity will be 
documented.   
8.1 Efficacy Assessments 
8.1.1 Psoriasis Area and Severity Index 
The PASI is a measure of the average redness (erythema), thickness (induration), and 
scaliness (scaling); each graded on a 0 to 4 scale of the lesions, weighted by the area of 
involvement (Feldman and Krueger, 2005).  All assessments for a given subject should be 
made by the same observer/assessor, wherever possible.   
8.1.2 Static Physical Global Assessment 
The sPGA is a 6-point scale (0 to 5) used to measure the severity of disease (induration, 
scaling, and erythema, Section 10.3, Appendix 3).  The sPGA should be completed by the same 
assessor performing the PASI assessments.  All assessments for a given subject should be 
made by the same observer/assessor, whenever possible.   
8.1.3 Affected Body Surface Area 
The percent of affected BSA affected is estimated by assuming that the subject’s palm, 
excluding the fingers and thumb, represents roughly 1% of the body’s surface  
(Chandran, 2009).  At any given visit, BSA should be performed by the same assessor 

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performing PASI assessment.  Because of interobserver variability in estimated BSA, all 
assessments for a given subject should be made by the same observer/assessor, whenever 
possible.   
8.2 Safety Assessments 
8.2.1 Physical Examinations 
Physical examination findings will be recorded and performed by a physician.   
Clinically significant abnormal changes from baseline will be reported as adverse events.   
Body weight (kg) and height will be measured with the subject dressed in light clothing, without 
shoes or jacket.   
Investigators should pay special attention to clinical signs related to previous serious illnesses.  
Any new abnormalities or worsening of existing abnormalities should be reported as adverse 
events, as appropriate (Section 8.3).   
8.2.2 Vital Signs 
Vital signs will be measured after the subject has been resting for 5 minutes and will include 
systolic and diastolic blood pressure, pulse, respiratory rate, and body temperature.   
Systolic and diastolic blood pressure will be measured on the same arm.   
During the study, the measurement of vital signs may be repeated at the discretion of the 
investigator for safety reasons.  Clinically relevant abnormal findings should be reported as 
adverse events.   
8.2.3 Tuberculosis Testing 
A tuberculosis test will be performed at screening by PPD or QuantiFERON®/T-spot® test.  
Further tuberculosis tests could be performed at the discretion of the investigator and according 
to local practice.  Purified protein derivative tests will be performed locally, and 
QuantiFERON®/T-spot® tests will be performed by the local or central laboratory.  Subjects with 
positive or indeterminate QuantiFERON®/T-spot® test, positive PPD may be eligible based on 
the sponsor’s tuberculosis assessment worksheet and the other criteria listed in inclusion 
criterion 7.   

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8.2.4 Chest Radiography 
Chest radiography will include anterior/posterior or posterior/anterior and lateral views.  
Historical films or formal reports signed off by a radiologist obtained in the 3 months prior to 
screening are acceptable.  Chest X-ray may be substituted by a chest CT or chest MRI, if 
available within 3 months prior to screening. 
8.2.5 Clinical Safety Laboratory Assessments 
Refer to the list of clinical laboratory tests (Table 8-1) to be performed and to the Schedule of 
Assessments (Table 1-1) for the timing and frequency.   
Urine pregnancy tests will be performed locally.  Purified protein derivative and 
QuantiFERON®/T-spot® tests will be performed by the local or central laboratory as described in 
the Schedule of Assessments (Table 1-1).  All other laboratory assessments will be performed 
by a central laboratory.  Blood and urine samples will be collected at the times indicated in the 
Schedule of Assessments (Table 1-1).  At visits when investigational product is administered, 
clinical laboratory samples will be collected before investigational product administration.  
Venous blood samples will be taken for hematology and biochemistry testing at visits specified 
in the Schedule of Assessments (Table 1-1).   
Refer to the investigator Laboratory Manual for details regarding the collection, processing, and 
shipping of the blood and urine samples.   
Any blood samples (eg, PK, immunogenicity) collected according to the Schedule of 
Assessments (Table 1-1) can be analyzed for any of the tests outlined in the protocol and for 
any tests necessary to minimize risks to study subjects.  This includes testing to ensure 
analytical methods produce reliable and valid data throughout the course of the study.  This can 
also include, but is not limited to, investigation of unexpected results, incurred sample 
reanalysis, and analyses for method transfer and comparability.   
Additional and repeat laboratory safety testing may be performed at the discretion of the 
investigator.   
The investigator (or designee) must review the laboratory report, document this review, and 
record any clinically relevant changes occurring during the study in the adverse event section of 
the case report form (CRF).  The laboratory reports must be filed with the source documents.  
Clinically relevant abnormal laboratory findings are those which are not associated with the 

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underlying disease, unless judged by the investigator to be more severe than expected for the 
subject's condition.   
Table 8-1. 
Protocol-required Safety Laboratory Assessments 
Laboratory Assessments 
Parameters 
Hematology 
Absolute neutrophil count 
Hematocrit 
Hemoglobin 
Platelet count 
RBC count 
WBC count (total) 
WBC count (differential) 
Clinical Chemistry 
Blood urea nitrogen 
Potassium 
Total bilirubin 
Creatinine 
Sodium 
Total protein 
Albumin 
Glucose (random) 
Alkaline phosphatase 
AST 
ALT 
gamma-glutamyl transferase 
Routine Urinalysis 
pH, specific gravity, glucose, bilirubin, blood, and protein 
Other Screening Tests 
FSH and estradiol (as needed in non-females of childbearing potential only) at 
screening 
Serum hCG pregnancy test (as needed for females of childbearing potential) at 
screening 
Serology (HBsAg, HBcAb, HCV, and HIV) at screening 
TBa testing (including a TB worksheet and chest X-ray) at screening 
Urine pregnancy tests 
Creatinine clearance 
Immunology (ADA) 
ADA = antidrug antibody; ALT = alanine aminotransferase; AST = aspartate aminotransferase; 
FSH = follicle-stimulating hormone; HBcAb = hepatitis B core antibody; HBsAg = hepatitis B surface antigen; 
hCG = human chorionic gonadotropin; HCV = hepatitis C virus; RBC = red blood cell; TB = tuberculosis; WBC = white 
blood cell; QuantiFERON®/T-spot® or purified protein derivative testing. 
8.3 Adverse Events and Serious Adverse Events 
8.3.1 Definitions 
8.3.1.1 Adverse Events 
An adverse event is any untoward medical occurrence in a clinical trial subject.  The event does 
not necessarily have a causal relationship with the investigational product.  An adverse event 
can therefore be an unfavorable and unintended sign (including an abnormal laboratory finding), 
symptom, or disease (new or exacerbated) temporally associated with the use of a treatment, 
combination product, medical device, or procedure.  The investigator is responsible for ensuring 
that any adverse events observed by the investigator or reported by the subject are recorded in 
the subject’s medical record as well as the electronic case report form (eCRF).   

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8.3.1.1.1 Events Meeting the Adverse Event Definition 
Events that meet the adverse event definition: 
• 
Any abnormal laboratory test results (hematology, clinical chemistry, or urinalysis) 
or other safety assessments (eg, electrocardiogram, radiological scans, vital signs 
measurements), including those that worsen from baseline, considered clinically 
significant in the medical and scientific judgment of the investigator (eg, not 
related to progression of underlying disease).  Where applicable, clinical sequelae 
(not the laboratory abnormality) are to be recorded as the adverse event.  In 
addition, laboratory or other abnormal assessments (eg, vital signs) that are 
associated with signs and/or symptoms must be recorded as an adverse event or 
serious adverse event.   
• 
Exacerbation of a chronic or intermittent pre-existing condition including either an 
increase in frequency and/or intensity of the condition.   
• 
New conditions detected or diagnosed after investigational product administration 
even though it may have been present before the start of the study.   
• 
Signs, symptoms, or the clinical sequelae of a suspected drug-drug interaction.   
• 
Signs, symptoms, or the clinical sequelae of a suspected overdose of either 
investigational product or a concomitant medication.  Overdose per se will not be 
reported as an adverse event/serious adverse event unless it is an intentional 
overdose taken with possible suicidal/self-harming intent.  Such overdoses should 
be reported regardless of sequelae.  In case of overdosage, it is recommended 
that the subject be monitored for any signs or symptoms of adverse reactions or 
effects and appropriate symptomatic treatment be instituted immediately.   
• 
"Lack of efficacy" or "failure of expected pharmacological action" per se will not be 
reported as an adverse event or serious adverse event.  Such instances will be 
captured in the efficacy assessments.  However, the signs, symptoms, and/or 
clinical sequelae resulting from lack of efficacy will be reported as adverse events 
or serious adverse events if they fulfill the definition of an adverse event or 
serious adverse event.   

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8.3.1.1.2 Events NOT Meeting the Adverse Event Definition 
Events not meeting the adverse event definition include: 
• 
Medical or surgical procedure (eg, endoscopy, appendectomy): the condition that 
leads to the procedure is the adverse event.   
• 
Situations in which an untoward medical occurrence did not occur (social and/or 
convenience admission to a hospital [inpatient hospitalization for less than 
24 hours]).   
• 
Anticipated day to day fluctuations of pre-existing disease(s) or condition(s) 
present or detected at the start of the study that do not worsen.   
• 
A pre-existing condition that has not worsened during the study or involves an 
intervention such as elective cosmetic surgery or a medical procedure while on 
study is not considered an adverse event.   
8.3.1.2 Serious Adverse Event 
A serious adverse event is defined as any untoward medical occurrence that meets at least 1 of 
the following serious criteria: 
• 
Results in death (fatal).   
• 
Life threatening (places the subject at immediate risk of death).   
• 
Requires inpatient hospitalization or prolongation of existing hospitalization.   
• 
Results in persistent or significant disability/incapacity.   
• 
Congenital anomaly/birth defect.   
• 
Other medically important serious event.   
Definitions 
Life-threatening: The term “life-threatening” in the definition of “seriousness” refers to an event 
in which the subject was at risk of death at the time of the event.  It does not refer to an event, 
which hypothetically might have caused death, if it were more severe.  For example, drug 
induced hepatitis that resolved without evidence of hepatic failure would not be considered life-
threatening even though drug-induced hepatitis can be fatal.  It does not include an adverse 
event or suspected adverse reaction that, had it occurred in a more severe form, might have 
caused death.   

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Hospitalization: In general, hospitalization signifies that the subject has been detained (usually 
involving at least an overnight stay) at the hospital or emergency ward for observation and/or 
treatment that would not have been appropriate in the physician's office or outpatient setting.  
Complications that occur during hospitalization are an adverse event.  If a complication prolongs 
hospitalization or fulfills any other serious criteria, the event is serious.  When in doubt as to 
whether “hospitalization” occurred or was necessary, the adverse event should be considered 
serious.  Hospitalization for elective treatment of a pre-existing condition that did not worsen 
from baseline is not considered an adverse event.   
Disability/incapacity: The term disability means a substantial disruption of a person’s ability to 
conduct normal life functions.  This definition is not intended to include experiences of relatively 
minor medical significance such as uncomplicated headache, nausea, vomiting, diarrhea, 
influenza, and accidental trauma (eg, sprained ankle) which may interfere with or prevent 
everyday life functions but do not constitute a substantial disruption.   
Other medically important serious event: Medical or scientific judgment is to be exercised in 
deciding whether serious adverse event 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 subject or may require medical or surgical intervention to 
prevent 1 of the other outcomes listed in the above definition.  These events are typically to be 
considered serious.   
Examples of such events include invasive or malignant cancers, 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.   
8.3.1.3 Clinical Laboratory Abnormalities and Other Abnormal 
Assessments 
The investigator is responsible for reviewing all laboratory test results, including review of 
laboratory test results prior to subject enrollment and reviewing subsequent laboratory test 
results throughout the study.  The investigator will determine whether an abnormal value in an 
individual study subject represents a clinically significant change from the subject’s baseline 
values.  Laboratory abnormalities without clinical significance (based on the investigator's 
judgment) should not be recorded as adverse events or serious adverse events.  However, 
laboratory abnormalities (eg, clinical chemistry, hematology, and urinalysis abnormalities) that 

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require medical or surgical intervention or lead to investigational product interruption, 
modification, or discontinuation must be recorded as an adverse event or serious adverse 
event, as applicable.  Where applicable, clinical sequelae (not the laboratory abnormality) are to 
be recorded as the adverse event.  In addition, laboratory or other abnormal assessments 
(eg, vital signs) that are associated with signs and/or symptoms must be recorded as an 
adverse event or serious adverse event if they meet the definition of an adverse event or 
serious adverse event as described in Section 8.3.1.  If the laboratory abnormality is part of a 
syndrome, record the syndrome or diagnosis (eg, anemia), not the laboratory result 
(eg, decreased hemoglobin).   
8.3.2 Assessments of Adverse Events 
8.3.2.1 Severity 
The investigator will make an assessment of severity for each adverse event and serious 
adverse event reported during the study.  The assessment of severity will be based on Common 
Terminology Criteria for Adverse Events (CTCAE, version 4.03): 
http://ctep.cancer.gov/protocolDevelopment/electronic_applications/ctc.htm 
8.3.3 Causality 
The investigator is obligated to assess the relationship between investigational product and 
each occurrence of each adverse event or serious adverse event.   
Relatedness means that there are facts or reasons to support a relationship between 
investigational product and the event.   
The investigator will use clinical judgment to determine the relationship.   
Alternative causes, such as underlying disease(s), concomitant therapy, and other risk factors, 
as well as the temporal relationship of the event to study treatment administration will be 
considered and investigated.   
The investigator will also consult the Investigator’s Brochure in his/her assessment.   
For each adverse event or serious adverse event, the investigator must document in the 
medical notes that he/she has reviewed the adverse event or serious adverse event and has 
provided an assessment of causality.   

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There may be situations in which a serious adverse event has occurred and the investigator has 
minimal information to include in the initial report.  However, it is very important that the 
investigator always make an assessment of causality for every event before the initial 
transmission of the serious adverse event data.   
The investigator may change his/her opinion of causality in light of follow-up information and 
send a serious adverse event follow-up report with the updated causality assessment.   
The causality assessment is one of the criteria used when determining regulatory reporting 
requirements.   
8.3.4 Documenting and Reporting of Adverse Events 
The investigator is responsible for ensuring that all adverse events observed by the investigator 
or reported by the subject that occur from the time of enrollment through the EOS Visit are 
recorded in subject’s medical records as well as the applicable CRF Adverse Event Summary 
page.  The adverse event grading scale to be used for this study will be CTCAE version 4.03, as 
described in Section 8.3.2.1.   
The investigator must assign the following adverse event attributes: 
• 
Adverse event diagnosis or syndrome(s), if known (if not known, signs or 
symptoms)  
• 
Dates of onset and resolution  
• 
Severity (National Cancer Institute CTCAE version 4.03)  
• 
Assessment of relatedness to investigational product, other protocol required 
therapies or devices  
• 
Action taken 
The investigator must assess whether the adverse event is possibly related to the 
investigational product.  This relationship is indicated by a “yes” or “no” response to the 
question: “Is there a reasonable possibility that the event may have been caused by the 
investigational product?” The investigator is responsible for reviewing laboratory test results and 
determining whether an abnormal value in an individual study subject represents a clinically 
significant change from the subject’s baseline values.  In general, abnormal laboratory findings 
without clinical significance (based on the investigator's judgment) are not to be recorded as 
adverse events.  However, laboratory value changes that require treatment or adjustment in 

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current therapy are considered adverse events.  Where applicable, clinical sequelae (not the 
laboratory abnormality) are to be recorded as the adverse event.   
The investigator’s clinical judgment is used to determine whether a subject is to be removed 
from treatment due to an adverse event.  A subject, or subject’s legal representative, can also 
voluntarily withdraw from treatment due to an adverse event.  If the subject withdraws consent, 
the subject is encouraged to undergo, at a minimum, an EOS assessment.   
It is the investigator’s responsibility to review all documentation (eg, hospital notes, laboratory 
reports, and diagnostic reports) related to an adverse event.  Wherever possible, the 
investigator’s diagnosis, not the individual signs and symptoms, will be documented as the 
adverse event.   
It is not acceptable for the investigator to send photocopies of the subject’s medical records to 
sponsor or responsible CRO in lieu of completion of the CRF page.   
If specifically requested, the investigator may need to provide additional follow-up information, 
such as discharge summaries, medical records, or extracts from the medical records.  In this 
case, all subject identifiers, with the exception of the subject number, will be blinded on the 
copies of the medical records before submission to the sponsor or responsible CRO.   
Investigators are not obligated to actively seek adverse events or serious adverse events after 
the subject’s conclusion of study participation.  However, if the investigator learns of any serious 
adverse event, including death, at any time after a subject has been discharged from the study, 
and he/she considers the event to be reasonably related to the investigational product or study 
participation, the investigator must promptly notify the sponsor.   
8.3.4.1 Reporting of Serious Adverse Events 
The investigator is responsible for ensuring that all serious adverse events observed by the 
investigator or reported by the subject that occur after signing of the ICF through the EOS Visit 
are reported using the applicable CRF Adverse Event Summary page or via the paper serious 
adverse event report form for serious adverse events occurring during screening for subjects 
not enrolled.   
All serious adverse events must be documented, recorded, and transmitted to Amgen, or its 
designee, within 24 hours following the investigator’s knowledge of the event.   

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The investigator will submit any updated serious adverse event data to the sponsor or designee 
within 24 hours of it being available.   
The criteria for grade 4 in the CTCAE grading scale differs from the regulatory criteria for 
serious adverse events.  It is left to the investigator’s judgment to report these grade 4 
abnormalities as serious adverse events.   
If the electronic data capture (EDC) system is not functional, the serious adverse event can be 
reported by faxing a completed paper Serious Adverse Event Form to the fax number as 
indicated on the SAE form or by direct telephone communication with Amgen or its designee.  
The event must be updated electronically in the EDC system by the clinical study center once 
the EDC function resumes.   
After the study is completed at a given center, the EDC system will be taken off-line to prevent 
the entry of new data or changes to existing data.  If a center receives a report of a new serious 
adverse event from a study subject or receives updated data on a previously reported serious 
adverse event after the EDC has been taken off-line, then the center can report this information 
on a paper Serious Adverse Event Form.   
8.3.4.2 Regulatory Reporting Requirements for Serious Adverse 
Events 
If a subject is permanently withdrawn from protocol required therapies because of a serious 
adverse event, this information must be submitted to Amgen, or its designee.   
Prompt notification by the investigator to the sponsor (or designee) of serious adverse events is 
essential so that legal obligations and ethical responsibilities towards the safety of subjects and 
the safety of a study treatment under clinical investigation are met.   
The sponsor (or designee) has a legal responsibility to notify both the local regulatory authority 
and other regulatory agencies about the safety of a study treatment under clinical investigation.  
The sponsor (or designee) will comply with country-specific regulatory requirements relating to 
safety reporting to the regulatory authority, IRBs/IECs, and investigators.   
Individual safety reports must be prepared for suspected unexpected serious adverse reactions 
according to local regulatory requirements and sponsor (or designee) policy and forwarded to 
investigators as necessary.   

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An investigator who receives an individual safety report describing a serious adverse event or 
other specific safety information (eg, summary or listing of serious adverse events) from the 
sponsor (or designee) will file it along with the Investigator’s Brochure and will notify the 
IRB/IEC, if appropriate according to local requirements.   
To comply with worldwide reporting regulations for serious adverse events, the treatment 
assignment of subjects who develop serious, unexpected, and related adverse events may be 
unblinded by Amgen or designee before submission to regulatory authorities.  Aggregate 
analyses may also be unblinded by the Safety Assessment Team, as appropriate.  Investigators 
will receive notification of related serious adverse events reports sent to regulatory authorities in 
accordance with local requirements.   
8.3.4.3 Reporting of Serious Adverse Event After the Protocol 
Required Reporting Period 
There is no requirement to monitor study subjects for serious adverse events following the 
protocol required reporting period or after the EOS.  However, these serious adverse events can 
be reported to Amgen.  Per local requirements in some countries, investigators are required to 
report serious adverse events that they become aware of after the EOS.  If serious adverse 
events are reported, the investigator is to report them to Amgen within 24 hours following the 
investigator’s knowledge of the event.   
Serious adverse events reported outside of the protocol-required reporting period will be 
captured within the safety database as clinical study cases and handled accordingly based on 
relationship to investigational product.   
8.3.4.4 Method of Detecting Adverse Events and Serious Adverse 
Events 
Care will be taken not to introduce bias when detecting adverse events and/or serious adverse 
events.  Open-ended and nonleading verbal questioning of the subject is the preferred method 
to inquire about adverse event occurrence.   
8.3.4.5 Adverse Event and Serious Adverse Event Follow-up 
During the study the adverse events and serious adverse events should be followed proactively 
by the investigator at subsequent visits/contact.  All adverse events and serious adverse events 

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will be followed until resolution, stabilization, until the event is otherwise explained, or until the 
subject is lost to follow-up.  At the time the subject’s study participation ends, all ongoing 
adverse events and serious adverse events should be evaluated for resolution.  All new or 
updated information for previously reported serious adverse events must be sent to Amgen 
within 24 hours following knowledge of the new information and will be recorded in the originally 
completed Adverse Event CRF.  If specifically requested, the investigator may need to provide 
additional follow-up information, such as discharge summaries, medical records, or extracts 
from the medical records.  Information provided about the serious adverse event must be 
consistent with that recorded on the Adverse Event CRF.   
The investigator is obligated to perform or arrange for the conduct of supplemental 
measurements and/or evaluations as medically indicated or as requested by Amgen to elucidate 
the nature and/or causality of the adverse event and serious adverse event as fully as possible.  
This may include additional laboratory tests or investigations, histopathological examinations, or 
consultation with other health care professionals.   
If a subject is permanently withdrawn from protocol required therapies because of a serious 
adverse event, this information must be submitted to Amgen.  If a subject dies during 
participation in the study, the investigator will provide Amgen with a copy of any post-mortem 
findings including histopathology if available.   
Events of interest are described in Section 8.3.6.  Formal pre-specified evaluations for events of 
interest are not planned at this time.   
8.3.5 Pregnancy 
Details of all pregnancies and/or lactation in female subjects and female partners of male 
subjects that occur after the start of study treatment and until 5 months after the last 
investigational product injection will be documented.   
If a pregnancy is reported, the investigator is to inform Amgen and/or designee within 24 hours 
of learning of the pregnancy and/or lactation and is to follow the procedures outlined in 
Section 10.2, Appendix 2.  Amgen Global Patient Safety or its designee will follow-up with the 
investigator regarding additional information that may be requested.   
Abnormal pregnancy outcomes (eg, spontaneous abortion, fetal death, stillbirth, congenital 
anomalies, ectopic pregnancy) are considered serious adverse events.   

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Further details regarding pregnancy and lactation are provided in Section 10.2, Appendix 2. 
8.3.6 Events of Interest 
Events of interest for ABP 501/adalimumab will be defined in the Statistical Analysis Plan (SAP) 
and will be reviewed on an ongoing basis as part of this study.  There are no additional 
expedited reporting requirements for events of interest, beyond what is defined for any adverse 
event report that qualifies to be expedited as part of regulatory reporting rules for investigational 
product.   
8.4 Treatment of Overdose 
The effects of overdose of ABP 501 are not known.  Doses up to 10 mg/kg of adalimumab 
(15 times the recommended dose) have been administered to patients in clinical trials without 
evidence of dose-limiting toxicities.   
8.5 Pharmacokinetics 
Serum samples will be collected for measurement of serum concentrations of investigational 
product as specified in the Schedule of Assessments (Table 1-1).  Instructions for the collection, 
handling, storage and shipment of biological samples will be provided in the Laboratory Manual.  
Blood samples for PK testing will be collected from all subjects.  PK samples for baseline, 
week 6, week 12, week 16, week 20, and week 28 should be taken prior to administration of 
investigational product.  PK samples for subsequent time points should be collected within the 
tolerance window specified in Table 1-2. 
The actual date and time (24-hour clock time) of each sample will be recorded.   
Samples collected for analyses of investigational product serum concentration may also be 
used to evaluate safety or efficacy aspects that address concerns arising during or after the 
study.   
8.6 Pharmacodynamics 
Pharmacodynamic parameters are not evaluated in this study.   
8.7 Genetics 
Genetics are not evaluated in this study.   

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8.8 Biomarkers 
Biomarkers are not evaluated in this study.   
8.9 Immunogenicity Assessments 
Antibodies (binding and neutralizing) to investigational product will be evaluated in serum 
samples collected from all subjects.  Additionally, serum samples should also be collected at the 
final visit from subjects who discontinued investigational product or were withdrawn from the 
study.  These samples will be tested by the sponsor or sponsor's designee.  Samples should be 
taken prior to administration of investigational product (predose) on dosing visits.  Samples 
tested positive for binding antibodies may be further assessed for neutralizing antibodies.  
Additional blood samples may be obtained to rule out ADAs during the study.   
The detection and characterization of ADAs will be performed using a validated assay method 
by the sponsor or under the supervision of the sponsor.   

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9 Statistical Considerations 
9.1 General Considerations 
All personnel involved with the analysis of the study will remain blinded until database lock.  
Analysis will be performed using SAS® version 9.4 or higher (SAS Institute, Cary, NC, US) by 
the sponsor or its representatives.   
The SAP will be developed and finalized prior to the unblinding for the final analysis.  The SAP 
will provide a detailed description of the statistical methods and expand on the details provided 
in the protocol.   
Data during the lead-in period, where all subjects are receiving adalimumab, will be presented 
as one group for the subjects who have been treated with IP.  All data post randomization will 
be presented by treatment group (switching group versus continued-use group).  Descriptive 
statistics (number of observations, mean, standard deviation, median, minimum, and maximum) 
will be provided for continuous variable, and counts and percentages will be presented for 
categorical variables.  Confidence intervals (CIs) and other inferential statistics may also be 
provided.   
In general, baseline will be defined as the last non missing measurement/procedure before or 
on the date of first administration of investigational product.   
9.2 Statistical Hypotheses 
The analysis of the primary PK endpoints will test the following hypotheses for each endpoint: 
Null Hypothesis (H0): The geometric mean ratio (GMR) between ABP 501 and adalimumab is 
outside a prespecified margin of 0.8, 1.25, 
versus 
Alternative Hypothesis (HA): The GMR between ABP 501 and adalimumab is within a 
prespecified margin of 0.8, 1.25. 
To establish that the risk in terms of safety or diminished efficacy of switching between ABP 501 
and adalimumab is not greater than the risk of using adalimumab without such switching 
(continuously), both of the 90% CI of GMRs of ABP 501 versus adalimumab for area under the 

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curve from time 0 over the dosing interval (AUCtau) and Cmax from the primary analysis must fall 
within the prespecified margin mentioned above.   
9.3 Sample Size Determination 
Approximately 414 subjects will be enrolled to receive adalimumab during the lead-in period.  
Subjects with prior biologic use for psoriasis will be capped at 50% of the total enrolled subjects.  
This sample size will ensure approximately 342 subjects will be randomized at week 12 after the 
lead-in period, considering 17% lead-in failures in a 1:1 ratio to the continued-use group or the 
switching group.  The randomization will be stratified by prior biologic use for psoriasis at 
baseline (week 1/day 1, yes vs. no) and geographic region.  The number of subjects enrolled 
may be adjusted during the study with the actual lead-in failure rate seen to ensure 
approximately 342 subjects will be randomized at week 12.  Subjects already enrolled will be 
allowed to be randomized at week 12.  The sample size of 342 randomized subjects will provide 
at least 90% power to demonstrate similarity of the primary PK endpoints based on the Two 
One-Sided Tests at a 0.05 significance level, assuming a between-subject variability (as 
measured by coefficient of variation) of 53% for ABP 501 and adalimumab, a true GMR of 1 
between ABP 501 and adalimumab, a similarity margin of 0.8, 1.25, and 15% dropouts after 
randomization through week 30 (including subjects who discontinue the study prior to week 28 
and those reaching week 28 but do not have evaluable primary PK endpoints between 
weeks 28 and 30).   
9.4 Populations for Analysis 
For purposes of analysis, the following analysis sets are defined in Table 9-1.  The Full Analysis 
Set will be analyzed according to the treatment that the subject is randomized to (regardless of 
actual treatment received).  For all other parameter sets, subjects will be analyzed according to 
the investigational product they actually received.  A precise definition of “as actually received” 
will be added in the SAP.   

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Table 9-1. 
Populations for Analysis 
Population (Analysis Set) 
Description 
Lead-in Treated Set 
The Lead-in Treated Set consists of all enrolled subjects treated with at least 
1 dose of investigational drug during the lead-in period.   
Full Analysis Set 
The Full Analysis Set consists of all randomized subjects (randomization 
occurs at week 12). 
Safety Analysis Set 
The Safety Analysis Set consists of all randomized subjects who received at 
least 1 dose of investigational product post randomization.   
PK Concentration Analysis Set 
The PK Concentration Analysis Set which will include all randomized subjects 
who received at least 1 dose of investigational product post randomization and 
have at least 1 reported serum concentration of ABP 501 or adalimumab. 
PK Parameter Analysis Set 
The PK Parameter Analysis Set consists of all subjects who are randomized 
and received all assigned doses post-randomization and who have an 
evaluable ABP 501 or adalimumab serum concentration-time profile between 
weeks 28 and 30 
Per Protocol PK Parameter 
Analysis Set 
The Per Protocol PK Parameter Analysis Set consists of all subjects in the PK 
Parameter Analysis Set who do not have an important protocol deviation that 
could affect the primary PK endpoints.   
Per Protocol Efficacy Analysis 
Set 
The Per Protocol Efficacy Analysis Set will include all subjects who are 
randomized and received all assigned doses post-randomization and who have 
not experienced an important protocol deviation that may affect the evaluation 
of the efficacy endpoints.   
PASI = Psoriasis Area and Severity Index; PK = pharmacokinetic(s); SAP = statistical analysis plan. 
9.5 Planned Analyses 
9.5.1 Primary Endpoints 
9.5.1.1 Primary Pharmacokinetic Endpoints 
The primary analysis of the primary PK endpoints, AUCtau, and Cmax, between weeks 28 and 30 
will be performed based on the PK Parameter Analysis Set, according to the actual treatment 
groups (switching group versus continued-use group).   
The point estimates and 90% CIs for the GMRs between ABP 501 and adalimumab for AUCtau 
and Cmax between weeks 28 and 30 will be estimated using an analysis of covariance 
(ANCOVA) model adjusting for stratification factors, weight, and PK trough concentration at the 
end of the lead-in period (week 12).  Prior to statistical modeling, the PK parameters will be 
logarithmically transformed (natural log).  Point estimates and 90% CIs for the mean difference 
in logarithmic PK parameters will be estimated from the ANCOVA model, which will then be 
transformed back to the original scale to obtain the point estimates and 90% CIs for GMR.   
AUCtau and Cmax of ABP 501 and adalimumab between weeks 28 and 30 will be listed by subject 
and summarized descriptively by treatment group.  A sensitivity analysis of the primary PK 
endpoints will be conducted on the Per Protocol PK Parameter Analysis Set.  To establish the 

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risk in terms of safety or diminished efficacy of switching between ABP 501 and adalimumab is 
not greater than the risk of using adalimumab without such switch, the 90% CI of GMRs of 
ABP 501 versus adalimumab for AUCtau and Cmax from the primary analysis should fall within the 
pre-specified similarity margin. 
9.5.2 Secondary Endpoint(s) 
9.5.2.1 Secondary Pharmacokinetic Endpoints 
The analyses of the secondary PK endpoints of time of maximum concentration (tmax) between 
weeks 28 and 30 and trough concentration (Ctrough) between weeks 14 and 28 will be based on 
the PK Parameter Analysis Set according to the actual treatment groups (switching group 
versus continued-use group).  tmax will be summarized descriptively by treatment group and 
Ctrough between weeks 14 and 28 will be summarized descriptively by visit and treatment group.  
The point estimates and 90% CIs for GMR for Ctrough between the two treatment groups will be 
estimated using an ANCOVA model adjusting for stratification factors, weight, and PK trough 
concentration at the end of the lead-in period (week 12).   
Mean serum concentration-time data post randomization will be presented graphically using PK 
Concentration Analysis Set. 
9.5.2.2 Secondary Efficacy Endpoints 
The analysis of the secondary efficacy endpoints will be based on the Per Protocol Efficacy 
Analysis Set according to the actual treatment groups (switching group versus continued-use 
group).  The point estimate and 90% CI of the mean difference in PASI percent improvement 
from day 1 at week 30 will be estimated from an ANCOVA model adjusting for the baseline 
PASI value and the stratification factors.  The point estimate and 90% CI of the risk differences 
in PASI 75, PASI 90, and PASI 100 response rates at week 30 will be estimated from a 
generalized linear model with an identity link adjusting for the stratification factors.   
Missing data will be imputed by last observation carry forward method for PASI percent 
improvement from day 1 at week 30 and by non-responder imputation for PASI 75, PASI 90, 
and PASI 100 response rates at week 30.  In addition, the PASI percent improvement from 
day 1 at week 30 and the PASI 75, PASI 90, and PASI 100 response rates at week 30 will be 
summarized descriptively by treatment group. 

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A sensitivity analysis will be conducted using observed data based on the Full Analysis Set 
according to randomized treatment groups. 
9.5.3 Safety Endpoints 
All reported adverse events will be categorized by system organ class and preferred term 
according to the Medical Dictionary for Regulatory Activities (latest version at the time of final 
analysis) dictionary and graded by CTCAE, version 4.03.   
Safety analyses of the safety endpoints will be performed based on the Safety Analysis Set 
according to the actual treatment groups (switching group versus continued-use group).  
Treatment-emergent adverse events post randomization are defined as adverse events that 
start or worsen on or after the first dose of investigational product post randomization and prior 
to the EOS.  The numbers and percentages of subjects reporting treatment-emergent adverse 
events, serious adverse events and events of interests will be tabulated by treatment group.  
The number and percent of subjects developing binding or neutralizing antidrug antibody (ADA) 
in the subset of Safety Analysis Set who have at least one ADA result post randomization will be 
tabulated descriptively by treatment group and by visit.   
Laboratory data (hematology, serum chemistry, and urinalysis) will be converted to Système 
International units for reporting purposes.  Absolute values and changes from week 12 for 
laboratory data post randomization will be summarized descriptively by treatment group and 
visit.   
For vital signs post randomization, absolute values, and changes from week 12 will be 
summarized descriptively by treatment group and visit.   
Physical examination values post randomization will be summarized descriptively by treatment 
group and by visit.   
9.5.4 Other Analyses 
9.5.4.1 Efficacy 
The analyses of the other efficacy endpoints in this section will be based on the Per Protocol 
Efficacy Analysis Set.   

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The PASI percent improvement from day 1 at other time points between week 12 and week 30 
and the PASI 75, PASI 90, and PASI 100 response rates at other time points between week 12 
and week 30 will be summarized descriptively by treatment group.   
Body surface area absolute values and changes from baseline will be summarized descriptively 
by visit and actual treatment group; the change from baseline in BSA at week 30 will be 
analyzed in a similar manner as the PASI percent improvement from baseline at week 30.   
The sPGA scores will be summarized descriptively by visit and treatment group.  The sPGA 
response (0/1) will also be summarized descriptively by visit and actual treatment group; the 
sPGA response (0/1) at week 30 will be analyzed similarly as the PASI 75 and PASI 100 
response rates at week 30.   
9.5.4.2 Analyses for the Lead-in Period 
All analyses for the lead-in period will be based on the Lead-in Treated Set.   
Available serum concentrations over time will be summarized descriptively for each scheduled 
visit during the lead-in period.   
Treatment-emergent adverse events during the lead-in period are defined as adverse events 
that start or worsen on or after the first dose of investigational product and prior to the first dose 
post randomization or EOS for lead-in failures.   
The number and percentage of subjects reporting treatment-emergent adverse events, serious 
adverse events and events of interest during the lead-in period will be summarized.   
The number and percentage of subjects developing binding or neutralizing ADAs during the 
lead-in period will be summarized.   
9.5.5 Demographic and Baseline Characteristics 
Demographic characteristics (including age, sex, ethnicity, and race) and baseline 
characteristics (including height, body weight, body mass index, and disease characteristics) will 
be presented descriptively by treatment group for the Lead-in Treated Set and for the other 
analysis sets defined in Section 9.4.   

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9.5.6 Exposure to Investigational Product 
Exposure to investigational product will be summarized descriptively by treatment group for the 
Lead-in Treated Set and for the Safety Analysis Set for the lead-in period and post 
randomization period, respectively.   
9.5.7 Exposure to Prior and Concomitant Medication 
Prior and concomitant medications will be coded using the latest available World Health 
Organization Drug Dictionary as of the time of the final analysis and will be summarized 
descriptively.  Concomitant medications during the lead‑in period will be summarized for the 
Lead-in treated Set and Safety Analysis Set while concomitant medication during the post 
randomization period will be summarized for the Safety Analysis Set.   
9.5.8 Subgroup Analyses and Covariates 
The stratification factors (prior biologic use for psoriasis [“yes” versus “no”] at baseline [week 1], 
and geographic region) will be included as covariates in the statistical models for the PK and 
efficacy analyses.  In addition, weight and PK trough concentration at the end of the lead-in 
period (week 12) will be included as covariates in the statistical model for the primary PK 
endpoints.  Baseline PASI score will be included as covariate in the statistical model for the 
PASI percent improvement efficacy endpoint. 
Subgroup analyses will be conducted for PK parameter endpoints for neutralizing ADA negative 
subgroup from the PK Parameter Analysis Set.   
Full details of the subgroup analyses and covariates will be pre-specified in the SAP.   
9.6 Interim Analyses 
No interim analysis is planned for this study.   

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10 Supporting Documentation and Operational Considerations 
10.1 Appendix 1: Regulatory, Ethical, and Study Oversight 
Considerations 
10.1.1 Regulatory and Ethical Considerations 
• 
This study will be conducted in accordance with the protocol and with: 
o Consensus ethical principles derived from international guidelines 
including the Declaration of Helsinki and Council for International 
Organizations of Medical Sciences International Ethical Guidelines.   
o Note for Guidance on ICH GCP Harmonized Tripartite Guideline E6 
(R1)/Integrated Addendum E6 (R2); US FDA CFR (Title 21 Parts 50, 56, 
312), requirements for the conduct of clinical studies as provided in the EU 
Directive 2001/20/EC, and all applicable laws and regulations.   
• 
The protocol, protocol amendments, ICF, any ICF updates, Investigator’s 
Brochure, subject facing recruitment materials (eg, advertisements) and other 
relevant documents to be provided to subjects (if applicable) must be submitted to 
an IRB/IEC by the investigator and reviewed and approved by the IRB/IEC before 
the study is initiated.   
• 
A copy of the written approval of the protocol and ICF must be received by Amgen 
or designee before recruitment of subjects into the study and shipment of Amgen 
investigational product.  Amgen may amend the protocol at any time.  The 
IRB/IEC approval(s) must identify the protocol version as well as the documents 
reviewed.   
• 
Any amendments to the protocol will require IRB/IEC approval before 
implementation of changes made to the study design, except for changes 
necessary to eliminate an immediate hazard to study subjects.   
• 
The investigator will be responsible for the following: 
o Providing written summaries of the status of the study to the IRB/IEC 
annually or more frequently in accordance with the requirements, policies, 
and procedures established by the IRB/IEC.   

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o Notifying the IRB/IEC of serious adverse events or other significant safety 
findings, including adverse drug reactions that are both serious and 
expected, as required by IRB/IEC procedures.   
o Providing oversight of the conduct of the study at the study center and 
adherence to the requirements of all applicable regulations.   
o Promptly reporting deviations from, or changes to, the protocol to eliminate 
immediate hazards to the study subjects.   
o Obtaining annual IRB/IEC approval/renewal throughout the duration of the 
study.  Copies of the investigator’s reports and the IRB/IEC continuance of 
approval must be sent to Amgen or designee.   
o Overall conduct of the study at the site and adherence to requirements of 
21 CFR, ICH GCP guidelines, the IRB/IEC, European regulation 536/2014 
for clinical studies (if applicable), and all other applicable local regulations.   
10.1.2 Informed Consent Process 
In obtaining and documenting informed consent, the investigator should comply with the 
applicable regulatory requirement(s) and should adhere to GCP and to the ethical principles that 
have their origin in the Declaration of Helsinki.  Prior to the beginning of the study, the 
investigator should have the IRB/IEC's written approval/favorable opinion of the written ICF and 
any other written information to be provided to subjects.   
• 
The investigator or his/her representative will explain the purpose and nature of 
the study as well as possible adverse effects to the subject or his/her legally 
acceptable representative and answer all questions regarding the study.   
• 
Subjects must be informed that their participation is voluntary, and consent can be 
withdrawn at any point.   
• 
Subject data up to withdrawal of consent will be included in the analysis of the 
study, and where permitted, publicly available data can be included after 
withdrawal of consent.   
• 
Subjects or their legally acceptable representative will be required to sign a 
statement of informed consent that meets the requirements of US FDA CFR 
Title 21 Part 50, local regulations, ICH guidelines, Health Insurance Portability 
and Accountability Act requirements where applicable, and the IRB/IEC or study 
center.   

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• 
Prior to a subject’s participation in the study, the written ICF should be signed and 
personally dated by the subject or by the subject’s legally acceptable 
representative, and by the person who conducted the informed consent 
discussion.   
• 
The medical record must include a statement that written informed consent was 
obtained before the subject was enrolled to the study and the date the written 
consent was obtained.  Subject withdrawal of consent or discontinuation from 
study, study treatment, and/or procedures must also be documented in the 
subject’s medical records.   
• 
The original copy of the signed ICF will be retained at the study center.   
• 
A copy of the ICF and any other written information must be provided to the 
subject or the subject’s legally acceptable representative.   
• 
If a protocol amendment is required, the ICF may need to be revised to reflect the 
changes to the protocol.   
• 
If the ICF is revised, the revised ICF must have received the IRB/IEC's 
approval/favorable opinion in advance of its use.  Subjects must be informed of 
the changes to the ICF and must re-consent to the most current version during 
their participation in the study.  The subject or the subject’s legally acceptable 
representative should be informed in a timely manner if new information becomes 
available that may be relevant to the subject’s willingness to continue participation 
in the study.  The communication of this information should be documented.   
• 
The investigator is also responsible for asking the subject if the subject has a 
primary care physician and if the subject agrees to have his/her primary care 
physician informed of the subject’s participation in the clinical study unless it is a 
local requirement.  If the subject agrees to such notification, the investigator is to 
inform the subject’s primary care physician of the subject’s participation in the 
clinical study.  If the subject does not have a primary care physician and the 
investigator will be acting in that capacity, the investigator is to document such in 
the subject’s medical record.   
If a subject is unable to read or if a legally acceptable representative is unable to read, an 
impartial witness should be present during the entire informed consent discussion.  The witness 
should sign and personally date the ICF after: 

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• 
The written ICF and any other written information to be provided to subjects is 
read and explained to the subject or to the subject’s legally acceptable 
representative.   
• 
The subject or the subject’s legally acceptable representative has orally 
consented to the subject’s participation in the study.   
• 
The subject or the subject’s legally acceptable representative has signed and 
personally dated the ICF, if they are capable of doing so.   
By signing the ICF, the witness attests that the information in the ICF and any other written 
information was accurately explained to, and apparently understood by, the subject or the 
subject's legally acceptable representative, and that informed consent was freely given by the 
subject or the subject’s legally acceptable representative.   
10.1.3 Data Monitoring Committee 
For details on the DMC, refer to DMC Charter.  The DMC will evaluate unblinded safety data 
throughout the study and convene approximately every 6 months after the first subject is 
enrolled to review safety data and issue recommendations.  The DMC’s constitution and the 
details of their roles and responsibilities are described in the DMC Charter.   
A DMC will be formed with members consisting of individuals external to Amgen and the CRO 
chosen for their expertise in Ps.  Members of the DMC will include, at a minimum, physicians 
with relevant specialty expertise and statistician(s).  The primary role of this independent DMC 
will be to monitor safety data.   
In addition, the DMC will communicate any major safety concerns and recommendations 
regarding study modification or termination to Amgen senior management at any time during the 
conduct of the study.   
Records of DMC meetings will be maintained by the CRO in a restricted, unblinded location for 
the duration of the study.  Meeting records will be transferred and stored in the study TMF at the 
conclusion of the study.  Selected Amgen, or its designee, staff may serve as liaisons with the 
DMC, but will not be voting members.  Personnel at Amgen or its designee involved in 
preparation or review of DMC unblinded materials will not be otherwise involved in the study.   

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10.1.4 Financing and Insurance 
10.1.4.1 Contractual and Financial Details 
The investigator (and/or, as appropriate, the hospital administrative representative) and Amgen, 
or its designee, will sign a clinical study agreement prior to the start of the study, outlining 
overall Amgen, or its designee, and investigator responsibilities in relation to the study.   
10.1.4.2 Insurance, Indemnity, and Compensation 
The sponsor will take out reasonable third-party liability insurance cover in accordance with all 
legal requirements.  The civil liability of the investigator, the persons instructed by him or her 
and the hospital, practice, or institute in which they are employed and the liability of the sponsor 
with respect to financial loss due to personal injury and other damage that may arise as a result 
of the carrying out of this study are governed by the applicable law.   
The sponsor will arrange for subjects participating in this study to be insured against financial 
loss due to personal injury caused by the pharmaceutical products being tested or by medical 
steps taken in the course of the study.   
10.1.4.3 Financial Disclosure 
Investigators and sub investigators will provide the sponsor or designee with sufficient, accurate 
financial information in accordance with local regulations to allow the sponsor to submit 
complete and accurate financial certification or disclosure statements to the appropriate 
regulatory authorities.  Investigators are responsible for providing information on financial 
interests during the course of the study and for 1 year after completion of the study.   
10.1.5 Data and Records Management 
All clinical study information should be recorded, handled, and stored in a way that allows its 
accurate reporting, interpretation, and verification.  This principle applies to all records 
referenced in this protocol, irrespective of the type of media used.   
A CRF will be used to store and transmit subject information.  The CRF must be reviewed and 
electronically signed and dated by the investigator on an ongoing basis throughout the study.  
The investigator is responsible for verifying that the data entries are accurate and correct by 
signing the CRF.   

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Access to the CRF will be strictly password protected and limited to personnel directly 
participating in the study.  Data should be entered into the CRF completely by authorized site 
personnel (eg, investigators and the study coordinator).  The CRF must be completed as soon 
as possible after any subject evaluation or communication.  If data are to be changed due to 
erroneous input or other reason, an electronic audit trail will track these changes.  The CRFs 
and computers that store them must be accessible to CRAs and other regulatory auditors.   
During each study visit, a physician participating in the study will maintain progress notes in the 
subject’s medical records to document all significant observations.  At a minimum, these notes 
are to contain: 
• 
The date of the visit and the corresponding day or visit in the study schedule.   
• 
General condition and status remarks by the subject, including any significant 
medical findings.  The severity, frequency, duration, and resolution of any 
reported adverse event, and the investigator's assessment as to whether or not 
the reported adverse event is related to investigational product.   
• 
Changes (including dosages) in concomitant medications/therapies (including 
over-the-counter medications and vitamins or dietary supplements) or procedures. 
• 
A general reference to the procedures completed.   
• 
The signature or initials of all physicians making an entry in the medical record 
(progress notes).   
In addition, any contact with the subject by telephone or other means that provides significant 
clinical information is to also be documented in the medical record (progress notes), as 
described above.   
Information from the medical records (progress notes) and other source documents is to be 
promptly entered into the appropriate section of the CRF as applicable.   
Changes to information in the medical record (progress notes) and other source documents are 
to be initialed and dated on the day the change is made by the investigator (or designee).  If the 
reason for the change is not apparent, a brief explanation for the change is to be written 
adjacent to the change.  Changes to the CRF will be electronically tracked.   

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10.1.5.1 Source Documentation 
Source documents contain the results of original observations and activities of a clinical 
investigation.  They are the original records in which raw data are first recorded.  Source 
documents include, but are not limited to, medical records (progress notes), computer printouts, 
screening logs, completed scales, and recorded data from automated instruments.   
The investigator/site personnel should maintain adequate and accurate source documents and 
study records that include all pertinent observations on each of the study center’s study 
subjects.  Source data should be attributable, legible, contemporaneous, original, accurate, and 
complete.  Changes to source data should be traceable, should not obscure the original entry, 
and should be explained if necessary (eg, through an audit trail).   
All source documents from this study are to be maintained by the investigator and made 
available for inspection by authorized persons.  The investigator will provide direct access to 
source documents/data for study related monitoring, audits, IRB/IEC review, and regulatory 
inspections.  They will be carried out giving due consideration to data protection and medical 
confidentiality.  The sponsor should verify that each subject has consented, in writing, to direct 
access to his/her original medical records for study related monitoring, audit, IRB/IEC review, 
and regulatory inspection.   
During the study, a CRA will review protocol compliance, compare CRF entries and individual 
subject’s medical records, assess drug accountability, and ensure that the study is being 
conducted according to pertinent regulatory requirements.   
10.1.5.2 Case Report Form 
The file structure and format for the CRF will be provided by the sponsor or its representative 
and should be handled in accordance with the instructions provided.   
Data will be entered/loaded into a validated electronic database using a clinical data 
management system.  Computerized data cleaning checks will be used in addition to manual 
review to check for discrepancies and to ensure consistency of the data.   
If corrections are needed, the responsible monitor or data manager will raise a query in the EDC 
application.  The appropriate staff at the study site will answer queries sent to the investigator.  
The name of the staff member responding to the query, and time and date stamp will be 
captured to provide an audit trail.   

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The specific procedures to be used for data entry and query resolution using the EDC 
system/eCRF will be provided to study sites in a training manual.  In addition, site personnel will 
receive training on the EDC system/eCRF.   
10.1.5.3 Study Files and Record Retention 
All data derived from the study will remain the property of the sponsor.  The sponsor assumes 
accountability for actions delegated to other individuals, eg, the CRO.   
Records must be retained in accordance with the current ICH Guidelines on GCP.  All essential 
study documents, including records of subjects, source documents, CRFs, and the 
investigational product inventory, must be kept on file.   
Essential documents should be retained until at least 2 years after the last approval of a 
marketing application in an ICH region and until there are no pending or contemplated 
marketing applications in an ICH region, or until at least 2 years have elapsed since the formal 
discontinuation of clinical development of ABP 501.  However, essential documents may be 
retained for a longer period if required by the applicable regulatory requirements or by 
agreement with the sponsor.  The sponsor is responsible for informing the investigator when 
these documents need no longer be retained.   
If an investigator moves, withdraws from a study, or retires, the responsibility for maintaining the 
records may be transferred to another person who will accept responsibility.  Notice of transfer 
must be made to and agreed by the sponsor.   
Source documents provide evidence for the existence of the subject and substantiate the 
integrity of the data collected.  Source documents are filed at the investigator’s site.   
Data reported on the CRF or entered in the eCRF that are transcribed from source documents 
must be consistent with the source documents or the discrepancies must be explained.  The 
investigator may need to request previous medical records or transfer records, depending on 
the study.  Also, current medical records must be available.   
The study start date is the date on which the first subject is enrolled to the study.  The EOS date 
is defined as the date when the last subject across all centers is assessed or receives an 
intervention for evaluation in the study (ie, last subject visit) or has withdrawn prematurely, as 
applicable.   

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The sponsor reserves the right to close the study site or terminate the study at any time for any 
reason at the sole discretion of the sponsor.  Study sites will typically be closed upon study 
completion.  A study site is considered closed when all required documents and study supplies 
have been collected and a study site closure visit has been performed.   
The investigator may initiate study site closure at any time, provided there is reasonable cause 
and sufficient notice is given in advance of the intended termination.   
Reasons for the early closure of a study site by the sponsor or investigator may include but are 
not limited to: 
• 
Failure of the investigator to comply with the protocol, the requirements of the 
IRB/IEC or local health authorities, the sponsor’s procedures, or GCP guidelines.   
• 
Inadequate recruitment of subjects by the investigator.   
• 
Discontinuation of further investigational product development.   
10.1.6 Publication Policy 
This study will be registered on ClinicalTrials.gov in accordance with applicable laws and 
publication policy and may also be registered on other publicly accessible websites, as 
necessary.  The results of the study will be posted for public disclosure within 12 months of 
study completion.   
The sponsor or designee is responsible for preparing and providing the appropriate regulatory 
authorities with the clinical study report (CSR) according to the applicable regulatory 
requirements.  The sponsor should ensure that the CSR meets the standards of the ICH 
Guideline for Structure and Content of CSRs (ICH E3).   
To coordinate dissemination of data from this study, Amgen may facilitate the formation of a 
publication committee consisting of several investigators and appropriate Amgen staff.  The 
criteria described below are to be met for every publication.   
Authorship of any publications resulting from this study will be determined on the basis of the 
Uniform Requirement for Manuscripts Submitted to Biomedical Journals International committee 
of Medical Journal Editors’ Recommendations for the Conduct of Reporting, Editing, and 
Publications of Scholarly Work in Medical Journals, which states: Authorship credit is to be 
based on: 

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1. Substantial contributions to conception and design, acquisition of data, or analysis and 
interpretation of data.   
2. Drafting the article or revising it critically for important intellectual content.   
3. Final approval of the version to be published; and  
4. Agreement to be accountable for all aspects of the work in ensuring that questions related to 
the accuracy or integrity of any part of the work are appropriately investigated and resolved. 
Authors need to meet conditions 1, 2, 3, and 4.   
When a large, multicenter group has conducted the work, the group is to identify the individuals 
who accept direct responsibility for the manuscript.  These individuals must fully meet the 
criteria for authorship defined above.  Acquisition of funding, collection of data, or general 
supervision of the research group, alone, does not justify authorship.  All persons designated as 
authors must qualify for authorship, and all those who qualify are to be listed.  Each author must 
have participated sufficiently in the work to take public responsibility for appropriate portions of 
the content.  All publications (eg, manuscripts, abstracts, oral/slide presentations, book 
chapters) based on this study must be submitted to Amgen for review.  The Clinical Trial 
Agreement among the institution, investigator, and Amgen will detail the procedures for, and 
timing of, Amgen’s review of publications.   
10.1.7 Auditing and Monitoring 
Sponsor-assigned CRAs will conduct regular center visits to the investigational facilities for the 
purpose of monitoring various aspects of the study, such as assessing subject recruitment, 
compliance with protocol procedures, completeness and accuracy of data entered into the 
CRFs, verification of CRF data against original source documents, occurrence of adverse 
events and the safety and rights of subjects are being protected, and that the study is being 
conducted in accordance with the currently approved protocol and any other study agreements, 
ICH GCP, and all applicable regulatory requirements.  The investigator must agree to -sponsor-
authorized personnel having direct access to the clinical (or associated) files and clinical study 
supplies (dispensing and storage areas) to ensure compliance with applicable regulations, and 
the investigator will assist with the sponsor’s monitoring activities.   
Quality control will occur at each stage of data handling to ensure that all data are reliable and 
have been processed correctly.  The sponsor should ensure oversight of any study related 

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duties and functions carried out on its behalf, including study related duties and functions that 
are subcontracted to another party by the sponsor’s contracted CRO(s).   
The CRFs should be completed in a timely manner and on an ongoing basis to allow regular 
review by the CRA.  Details describing the strategy, responsibilities, and requirements of the 
study monitoring are provided in the Study Monitoring Plan. 
The purpose of an audit is to assess whether ethics, regulatory, and quality requirements are 
being fulfilled.  The sponsor or its representative may conduct audits at the investigative centers 
including, but not limited to, drug supply, presence of required documents, the informed consent 
process, and comparison of CRFs with source documents.  Government regulatory authorities 
may also inspect the investigator during or after the study.   
The investigator (or designee) should contact the sponsor/CRO immediately if this occurs.  All 
medical records (progress notes) must be available for audit.  The investigator must agree to 
participate with audits conducted at a convenient time in a reasonable manner.   
10.1.7.1 Risk and Quality Tolerance Limits 
Perceived risks and quality tolerance limits (QTLs) will be identified and documented before the 
start of the study. 
The sponsor and CRO will review risk control measures periodically to ascertain whether the 
implemented quality management activities remain effective and relevant.  The quality 
management approach and any important deviations from the predefined QTLs (and remedial 
actions adopted) will be described in the CSR.   
10.1.7.2 Protocol Adherence and Deviations 
The investigator and site personnel should conduct the study in compliance with the protocol 
and should use continuous vigilance to identify and report protocol deviations.   
A protocol deviation is any change, divergence, or departure from the study design or 
procedures defined in the protocol that may be on the part of the investigator, site personnel, or 
the subject.   
Important protocol deviations are a subset of protocol deviations that may significantly impact 
the completeness, accuracy, and/or reliability of the study data or that may significantly affect a 
subject’s rights, safety, or well-being.  For example, important protocol deviations may include 

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randomizing subjects in violation of key eligibility criteria designed to ensure a specific subject 
population or failing to collect data necessary to interpret primary endpoints, as this may 
compromise the scientific value of the study.   
The investigator should not implement any deviation from the protocol without agreement from 
the sponsor and prior review and approval from the IRB/IEC of an amendment, except where 
necessary to eliminate an immediate hazard to a study subject.  In the event of an important 
protocol deviation, the investigator will discuss the deviation with the sponsor’s medical monitor 
and will come to an agreement as to whether the subject should be withdrawn from the study 
due to the important protocol deviation.   
10.1.8 Data Protection 
Subjects will be assigned a unique identifier by the sponsor.  Any subject records or datasets 
that are transferred to the sponsor will contain the identifier only; subject names or any 
information which would make the subject identifiable will not be transferred.   
The subject must be informed that his/her personal study-related data will be used by the 
sponsor in accordance with local data protection law.  The level of disclosure must also be 
explained to the subject.   
The subject must be informed that his/her medical records may be examined by Clinical QA 
auditors or other authorized personnel appointed by the sponsor, by appropriate IRB/IEC 
members, and by inspectors from regulatory authorities.   
10.1.9 Protocol Approval and Amendment 
Protocol modifications, except those intended to reduce immediate risk to study subjects, may 
be made only by the sponsor.   
Any permanent change to the protocol must be handled as a protocol amendment.  The written 
amendment must be submitted to the IRB/IEC, and the investigator must await approval before 
implementing the changes.  The sponsor or designee will submit protocol amendments to the 
appropriate regulatory authorities for approval.   
The current version of the ICF will require similar modification if the IRB/IEC, investigator, and/or 
sponsor, judge the amendment to the protocol to substantially change the study design and/or 
increase the potential risk to the subject and/or impact the subject's involvement as a study 

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subject.  In such cases, the ICF will be renewed for enrolled subjects before their continued 
participation in the study.   
10.1.10 
Study and Site Start and Closure 
The study start date is the date on which the first subject is enrolled to the study.  The EOS date 
is defined as the date when the last subject across all centers is assessed or receives an 
intervention for evaluation in the study (ie, last subject visit) or has withdrawn prematurely, as 
applicable.   
The sponsor designee reserves the right to close the study site or terminate the study at any 
time for any reason at the sole discretion of the sponsor.  Study sites will typically be closed 
upon study completion.  A study site is considered closed when all required documents and 
study supplies have been collected and a study site closure visit has been performed.   
The investigator may initiate study site closure at any time, provided there is reasonable cause 
and sufficient notice is given in advance of the intended termination.   
Reasons for the early closure of a study site by the sponsor or investigator may include but are 
not limited to: 
• 
Failure of the investigator to comply with the protocol, the requirements of the 
IRB/IEC or local health authorities, the sponsor's procedures, or GCP guidelines.   
• 
Inadequate recruitment of subjects by the investigator.   
• 
Discontinuation of further investigational product development.   
If the study is prematurely terminated or suspended, the sponsor shall promptly inform the 
investigators, the IECs/IRBs, the regulatory authorities, and any contract research 
organization(s) used in the study of the reason for termination or suspension, as specified by 
the applicable regulatory requirements.  The investigator shall promptly inform the subject and 
should assure appropriate subject follow-up.   
10.2 Appendix 2: Contraceptive Guidance and Collection of 
Pregnancy Information 
Study specific contraception requirements for males and females of childbearing potential are 
outlined in Section 5.2 exclusion criteria 22 and 23). 

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Male and female subjects of childbearing potential must receive pregnancy prevention 
counseling and be advised of the risk to the fetus if they become pregnant or father a child 
during treatment and for 5 months after the last dose of protocol required therapies.   
Additional medications given during the study may further alter the contraceptive requirements.  
These additional medications may require female subjects to use highly effective methods of 
contraception and/or for an increased length of time.  The investigator must discuss these 
contraceptive changes with the subject.   
Definitions 
Females of Childbearing Potential 
A woman is considered fertile following menarche and until becoming postmenopausal unless 
permanently sterile (see below).   
If fertility is unclear (eg, amenorrhea in adolescents or athletes) and a menstrual cycle cannot 
be confirmed before first dose of investigational product, additional evaluation should be 
considered.  For more details on the definitions, refer to Section 5.2. 
Women in the following categories are not considered females of childbearing potential: 
1. Premenarchal 
2. Premenopausal female with one of the following: 
• 
Documented hysterectomy.   
• 
Documented bilateral salpingectomy.   
• 
Documented bilateral oophorectomy.   
NOTE: Documentation can come from the site personnel’s review of the subject’s medical 
records, medical examination, or medical history interview.   
3. Postmenopausal female 
 A postmenopausal state is defined as no menses for 12 months without an alternative medical 
cause.   
• 
A high follicle stimulating hormone (FSH) level in the postmenopausal range may 
be used to confirm a postmenopausal state in women not using hormonal 
contraception or hormonal replacement therapy (HRT).  However, in the absence 
of 12 months of amenorrhea, a single FSH measurement > 40 IU/L is required.   

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• 
Females on HRT and whose menopausal status is in doubt will be required to use 
one of the non-estrogen hormonal effective contraception methods if they wish to 
continue their HRT during the study.  Otherwise, they must discontinue HRT to 
allow confirmation of postmenopausal status before study enrollment.   
Contraception Guidance 
Female Subjects: 
Female subjects of childbearing potential are eligible to participate if they agree to use one of 
the following acceptable effective method of contraception throughout the duration of the study 
and for 5 months after last dose of study drug.  as described below: 
• 
Combined (estrogen and progestogen containing) hormonal contraception 
associated with inhibition of ovulation (oral, intravaginal, or transdermal). 
• 
Progestogen-only hormonal contraception (oral, injectable, implantable). 
• 
Intrauterine device. 
• 
Intrauterine hormonal-releasing system. 
• 
Bilateral tubal ligation/occlusion. 
• 
Vasectomized partner (provided that partner is the sole sexual partner of the 
female subject of childbearing potential and that the vasectomized partner has 
received medical assessment of the surgical success). 
• 
Sexual abstinence (defined as refraining from heterosexual intercourse during the 
entire period of risk associated with the study treatments; the reliability of sexual 
abstinence must be evaluated in relation to the duration of the trial and the 
preferred and usual lifestyle of the subject). 
• 
Double barrier method: the male uses a condom and the female may choose 
either a cap, diaphragm, or sponge with spermicide (a female condom is not an 
option due to the risk of tearing when both partners use a condom). 
Male Subjects: 
Male participants are not required to use birth control during treatment with ABP 501.  However, 
female partner of the study male participant should be informed about the study and subject's 
participation. 

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Pregnancy Testing 
• 
Female of childbearing potential should only be included after a confirmed 
menstrual period and a negative highly sensitive serum pregnancy test.   
• 
Additional pregnancy testing should be performed at intervals as per the Schedule 
of Assessments (Table 1-1), and as required locally.   
• 
Pregnancy testing will be performed whenever a menstrual cycle is missed or 
when pregnancy is otherwise suspected.   
• 
Pregnancy testing, with a sensitivity of 5 mIU/mL will be performed. 
Collection of Pregnancy Information: 
Male Subjects With Partners Who Become Pregnant 
• 
In the event a male subject’s partner becomes pregnant during treatment, and for 
an additional 5 months after the last dose of investigational product, the 
information will be recorded on the Pregnancy Notification Form.  The form must 
be submitted to Amgen or its designee within 24 hours of the center’s awareness 
of the pregnancy (Note: Sites are not required to provide any information on the 
Pregnancy Notification Form that violates the country or regions local privacy 
laws).   

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• 
The investigator will attempt to obtain a signed authorization for release of 
pregnancy and infant health information directly from the pregnant female partner 
to obtain additional pregnancy information.   
• 
After obtaining the female partner’s signed authorization for release of pregnancy 
and infant health information, the investigator will collect pregnancy outcome and 
infant health information on the pregnant partner and her baby and complete the 
pregnancy questionnaires.  This information will be forwarded to Amgen or its 
designee. 
• 
Generally, infant follow-up will be conducted up to 12 months after the birth of the 
child (if applicable).   
• 
Any termination of the pregnancy will be reported to Amgen or its designee 
regardless of fetal status (presence or absence of anomalies) or indication for 
procedure.   
Female Subjects Who Become Pregnant 
• 
The investigator will collect pregnancy information on any female subject who 
becomes pregnant while taking protocol required therapies through 5 months after 
the last dose of investigational product.   
• 
Information will be recorded on the Pregnancy Notification Form.  The form must 
be submitted to Amgen or its designee within 24 hours of learning of a subject’s 
pregnancy (Note: Sites are not required to provide any information on the 
Pregnancy Notification Form that violates the country or regions local privacy 
laws).   
• 
After obtaining the female subject’s signed authorization for release of pregnancy 
and infant health information, the investigator will collect pregnancy and infant 
health information and complete the pregnancy questionnaire for any female 
subject who becomes pregnant while taking protocol required therapies through 
5 months after the last dose of investigational product.  This information will be 
forwarded to Amgen or its designee.  Generally, infant follow-up will be conducted 
up to 12 months after the birth of the child (if applicable).   
• 
Any termination of the pregnancy will be reported to Amgen or its designee 
regardless of fetal status (presence or absence of anomalies) or indication for 
procedure.   

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• 
While pregnancy itself is not considered to be an adverse event or serious 
adverse event, any pregnancy complication or report of a congenital anomaly or 
developmental delay, fetal death, or suspected adverse reactions in the neonate 
will be reported as an adverse event or serious adverse event.  Note that an 
elective termination with no information on a fetal congenital malformation or 
maternal complication is generally not considered an adverse event, but still must 
be reported to Amgen or its designee as a pregnancy exposure case.   
• 
If the outcome of the pregnancy meets a criterion for immediate classification as a 
serious adverse event (eg.  female subject experiences a spontaneous abortion, 
stillbirth, or neonatal death or there is a fetal or neonatal congenital anomaly) the 
investigator will report the event as a serious adverse event.   
• 
Any serious adverse event occurring as a result of a poststudy pregnancy which 
is considered reasonably related to the study treatment by the investigator, will be 
reported to Amgen or its designee.  While the investigator is not obligated to 
actively seek this information in former study subjects, he or she may learn of a 
serious adverse event through spontaneous reporting.   
• 
Any female subject who becomes pregnant while participating will discontinue 
study treatment.   
Collection of Lactation Information 
• 
Investigator will collect lactation information on any female subject who 
breastfeeds while taking protocol required therapies through 5 months after the 
last dose of investigational product.   
• 
Information will be recorded on the Lactation Notification Form and submitted to 
Amgen or its designee within 24 hours of the investigator’s knowledge of event.   
• 
Study treatment will be discontinued if female subject breastfeeds during the 
study as described in exclusion criterion 24 (Section 5.2).   
• 
With the female subjects signed authorization for release of mother and infant 
health information, the investigator will collect mother and infant health 
information and complete the lactation questionnaire on any female subject who 
breastfeeds while taking protocol required therapies through 5 months after 
discontinuing protocol required therapies.   

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10.3 Appendix 3: Static Physician’s Global Assessment Scale 
Below is the sPGA scale that will be used in this study.   
Score 
Category 
Category Description 
0 
Clear 
• 
Plaque elevation = 0 (no elevation over normal skin).   
• 
Scaling = 0 (no scale).   
• 
Erythema = no evidence, hyperpigmentation may be present.   
1 
Almost Clear 
• 
Plaque elevation = ± (possible but difficult to ascertain whether there is a slight 
elevation above normal skin).   
• 
Scaling = ± (surface dryness with some white coloration).   
• 
Erythema = light red coloration.   
2 
Mild 
• 
Plaque elevation = slight (slight but definite elevation, typically edges are 
indistinct or sloped).   
• 
Scaling =fine (fine scale partially or mostly covering lesions).   
• 
Erythema = light red coloration.   
3 
Moderate 
• 
Plaque elevation = moderate (moderate elevation with rough or sloped edges).   
• 
Scaling = coarser (coarse scale covering most or all of the lesions).   
• 
Erythema = moderate (definite red coloration).   
4 
Severe 
• 
Plaque elevation = marked (marked elevation typically with hard or sharp 
edges).   
• 
Scaling = coarse (coarse, non-tenacious scale predominates covering most or all 
of the lesions).   
• 
Erythema = severe (very bright red coloration).   
5 
Very Severe 
• 
Plaque elevation = very marked (very marked elevation typically with hard sharp 
edges).   
• 
Scaling = very coarse (coarse, thick tenacious scale over most of the lesions, 
rough surface).   
• 
Erythema = very severe (extreme red coloration, dusky to deep red coloration).   
 

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10.4 Appendix 4: Abbreviations and Trademarks 
ADA 
antidrug antibody 
ALT 
alanine aminotransferase 
AST 
aspartate aminotransferase 
ANCOVA 
analysis of covariance 
AUCtau 
area under the curve from time 0 over the dosing interval 
BCG 
Bacillus Calmette Guerin 
BPCI 
Biologic Price Competition and Innovation Act 
BSA 
body surface area 
CHO 
Chinese hamster ovary 
CI 
confidence interval 
Cmax 
maximum concentration 
COVID-19 
coronavirus disease 2019 
CRA 
clinical research associate 
CRF 
case report form 
CRO 
contract research organization 
CSR 
clinical study report 
CTCAE 
Common Terminology Criteria for Adverse Events 
Ctrough 
trough concentration  
DMC 
Data Monitoring Committee 
DNA 
deoxyribonucleic acid 
eCRF 
electronic case report form 
EDC 
electronic data capture 
EOS 
end of study 
EU 
European Union 
FSH 
follicle stimulating hormone 
GCP 
Good Clinical Practice 
GMR 
geometric mean ratio 
HBsAg 
hepatitis B surface antigen 
hCG 
human chorionic gonadotropin 
HCV 
hepatitis C virus 
HRT 
hormonal replacement therapy 
ICF 
informed consent form 
ICH 
International Council for Harmonization of Technical Requirements for 
Pharmaceuticals for Human Use 
IEC 
Independent Ethics Committee 
IL 
Interleukin 

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IMP 
investigational medicinal product 
IP 
investigational product 
IRB 
Institutional Review Board 
IV 
Intravenous 
IXRS 
Interactive Web/Voice Response System 
NIMP 
non-investigational medicinal product 
PASI 
Psoriasis Area and Severity Index 
PGA 
Physician’s Global Assessment 
PIN 
personal identification number 
PK 
pharmacokinetic(s) 
PPD 
purified protein derivative 
Ps 
plaque psoriasis 
RA 
rheumatoid arthritis 
RBC 
red blood cell 
sPGA 
static Physician’s Global Assessment 
TB 
Tuberculosis 
TNFRSF 
tumor necrosis factor receptor superfamily 
QA 
quality assurance 
QTL 
quality tolerance limit 
Q2W 
every 2 weeks 
RBC 
red blood cell 
SAP 
statistical analysis plan 
SARS-CoV-2 severe acute respiratory syndrome coronavirus 2 
SC 
Subcutaneous 
SmPC 
Summary of Product Characteristics 
tmax 
time of maximum concentration 
TNFα 
tumor necrosis factor alpha 
TMF 
trial Master File 
US 
United States 
USPI 
United States Prescribing Information 
WBC 
white blood cell 
 

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11 References 
Amgen Inc.  ABP 501 – Investigator’s Brochure Version 6.1, 2021.   
AMGEVITA® (adalimumab) Summary of Product Characteristics [SmPC]. March 2020.   
AMJEVITA™ (adalimumab-atto) United States Prescribing Information [USPI]. June 2019.   
Chandran V, Gottlieb A, Cook RJ, et al.  International multicenter psoriasis and psoriatic arthritis 
reliability trial for the assessment of skin, joints, nails, and dactylitis.  Arthritis Rheum.  
2009;61(9):1235-1242.  doi: 10.1002/art.24562.   
Feldman SR, Krueger GG.  Psoriasis assessment tools in clinical trials.  Ann Rheum Dis.  
2005;64 suppl 2(Suppl2):ii65-ii68;discussion ii69-ii73.  doi: 10.1136/ard.2004.031237.  
US FDA guidance (Guidance for Industry: Biosimilars: Considerations in Demonstrating 
Interchangeability with a Reference Product, May 2019.