A Phase 2, Randomized, Double-Blind, Placebo Controlled Study to Evaluate the Efficacy and Safety of Imsidolimab (ANB019) in the Treatment of Subjects With Hidradenitis Suppurativa
Phase: PHASE2
Conditions: Hidradenitis Suppurativa
Sponsor: Vanda Pharmaceuticals

 
Confidential and proprietary. Permission should be obtained before any reproduction.  
 
1 
A Phase 2, Randomized, Double-Blind, 
Placebo-Controlled Study to Evaluate the Efficacy 
and Safety of Imsidolimab (ANB019) in the 
Treatment of Subjects with Hidradenitis 
Suppurativa 
 
Protocol Number: ANB019-208 
Investigational New Drug (IND) Number: 136145 
European Clinical Trials Database (EudraCT) Number: TBD 
 
 
 
Sponsor Name: AnaptysBio, Inc. 
Sponsor Address: 10770 Wateridge Circle, Suite 210 
San Diego, CA 92121, United States 
 
Sponsor Medical Expert and Signatory: 
 
 
 
 
 
 
Amendment 1 
24 September 2021 
AnaptysBio, ANB019
IND 136145, SN 0059

Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
Amendment 1 
Protocol ANB019-208 
24 September 2021 
Confidential and proprietary. Permission should be obtained before any reproduction.  
 
5 
 
To clarify that tubal ligation is an accepted method of contraception. 
 
To remove troponin from the biochemistry panel 
 
Section # and Name 
Description of Change 
Brief Rationale 
Global  
Small editorial changes and 
corrections. 
To add clarity and 
implement corrections to 
text 
Title Page  
To update the Sponsor’s address. 
Administrative changes for 
Amendment 1
Title Page; Document Header; 
Document History Table 
To add Amendment 1 and date. 
Administrative changes for 
Amendment 1
Investigator’s Agreement 
To add amendment number. 
Administrative change for 
Amendment 1
Section 8.1.2 Patient Global 
Impression of Severity; Appendix 3 
Patient Global Impression of 
Severity
Changed the response options for 
the PGIS from “Clear skin” to 
“No activity”. 
To clarify the response 
option should be “no 
activity” rather than “clear 
skin”
Abbreviations; Section 1.1 Synopsis; 
Section 1.3 Schedule of Activities; 
Section 3.3 Exploratory Objectives 
and Endpoints; Section 4.1 Overall 
Design; Section 8.1.3 Patient Global 
Impression of Bother; Section 9.4.7 
Analysis of the Exploratory 
Endpoints; Appendix 4 Patient 
Global Impression of Bother
Added PGIB questionnaire and 
all corresponding endpoints. 
To evaluate if signs and 
symptoms of hidradenitis 
suppurativa are bothersome 
for the subjects. 
Section 1.3 Schedule of Activities; 
Section 8.3.1 Fitzpatrick Skin Type 
Classification; 10.1.9.1 Data 
Collection and Management 
Responsibilities; Appendix 12 
Fitzpatrick Skin Type Classification
Added an evaluation of subjects’ 
skin type using the Fitzpatrick 
skin type classification. 
To evaluate subjects’ skin 
pigment type.  
Section 1.3 Schedule of Activities; 
Section 10.1.9.1 Data Collection and 
Management Responsibilities 
Added collection of smoking 
history at D1 
To allow for sub-population 
efficacy analyses based on 
smoking status 
Section 1.3 Schedule of Activities; 
Section 8  
Clarify that a PK sample will not 
be collected postdose on Day 1. 
A PK sample within hours 
of the first SC dose is not 
necessary.
Section 1.3 Schedule of Activities; 
Section 8.3.3 
The order of assessments was 
updated to recommended rather 
than specific.
To allow for some flexibility 
in order of assessments. 
Section 1.1 Synopsis; Section 1.3 
Schedule of Activities; Section 4.1 
Overall Design; Section 8.3.2 
Photography
Modified photography to be an 
optional procedure rather than for 
documentation purposes only. 
To add photography as 
optional for all subjects at 
each visit. 
Section 1.1 Synopsis; Section 3.3 
Exploratory Objectives and 
Endpoints; Section 9.4.7 Analysis of 
the Exploratory Endpoints 
 Added a few exploratory 
efficacy endpoints.  
 Updated the exploratory 
endpoint to: “Proportion of 
To refine the exploratory 
efficacy analyses. 
AnaptysBio, ANB019
IND 136145, SN 0059

Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
Amendment 1 
Protocol ANB019-208 
24 September 2021 
Confidential and proprietary. Permission should be obtained before any reproduction.  
 
6 
Section # and Name 
Description of Change 
Brief Rationale 
subjects with ≥2-point reduction 
from Baseline on HS PGA at 
each visit”. 
 Changed the response options 
for the HS-PGA from “0 (clear) 
or 1 (minimal)” to “0 (inactive) 
or 1 (almost inactive)”.
Section 1.1 Synopsis; Section 5.1 
Inclusion Criteria 
The BMI limits were removed 
from Inclusion Criterion 9. 
To include HS population 
based on weight and not 
limit inclusion by BMI 
calculation. 
Section 1.1 Synopsis; Section 5.1 
Inclusion Criteria 
Inclusion Criterion 10a updated 
to: A male subject who has not 
had a vasectomy must agree to 
use contraception as detailed in 
Appendix 1….
To clarify that male subjects 
who are sterile following a 
vasectomy do not need to 
use additional contraception 
method(s).
Section 1.1 Synopsis; Section 5.1 
Inclusion Criteria 
Added the following clarification 
to the Inclusion Criterion 10.b.ii: 
A woman not of childbearing 
potential as defined in 
Appendix 1 is eligible to 
participate in the study. A 
postmenopausal woman must 
have a follicle stimulating 
hormone (FSH) test confirming 
nonchildbearing potential.
To clarify the inclusion 
criterion for a woman not of 
childbearing potential and 
for a postmenopausal 
woman. 
Section 1.1 Synopsis; Section 5.2 
Exclusion Criteria 
Exclusion Criterion 4 was 
modified as follows:  
Any evidence of active infection 
that required treatment with a 
systemic antibiotic, antiviral, or 
antifungal agent within 4 weeks 
of Day 1 (eg, bronchopulmonary, 
urinary, or gastrointestinal).
To clarify the systemic 
treatments that are not 
allowed within 4 weeks of 
Day 1 in case of active 
infection. 
Section 1.1 Synopsis; Section 5.2 
Exclusion Criteria 
Exclusion Criterion 8 was 
deleted. “Known or suspected 
autoimmune disorder, including 
but not limited to rheumatoid 
arthritis, ….” 
This exclusion criterion is 
overly restrictive and 
unnecessary, as a 
comprehensive general 
listing of concurrent medical 
conditions that adequately 
represents potential safety 
risks for subjects is already 
covered by Exclusion 
Criterion 2.
Section 1.1 Synopsis; Section 5.2 
Exclusion Criteria; Section 6.5 
Concomitant Therapy; Section 6.5.1 
Permitted Therapies; Section 6.5.2 
Exclusion Criterion 21 was 
clarified to include live in 
addition to live-attenuated 
vaccines, and corresponding 
To clarify the exclusion 
criterion related to live and 
live-attenuated vaccines. 
AnaptysBio, ANB019
IND 136145, SN 0059

Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
Amendment 1 
Protocol ANB019-208 
24 September 2021 
Confidential and proprietary. Permission should be obtained before any reproduction.  
 
7 
Section # and Name 
Description of Change 
Brief Rationale 
Prohibited Medications or 
Procedures 
sections referring to vaccines 
were revised too.
Section 1.1 Synopsis; Section 1.3 
Schedule of Activities; Section 5.2 
Exclusion Criteria 
The following note was removed 
from the schedule of activities in 
footnote related to tuberculosis 
testing: 
If a negative QuantiFERON®-TB 
Gold test result was obtained 
within 6 months of screening, it 
can be skipped at screening. 
Corresponding exclusion criterion 
(Exclusion Criterion 24) was also 
updated. 
To clarify that the 
tuberculosis testing is to be 
performed for all subjects at 
screening.  
Section 2.2.2 Clinical Studies; 
Section 2.3.1 Known Potential Risks 
Information on current clinical 
studies and new information on 
risks, including occurrence of 
serious adverse events, were 
added. 
To revise the introduction 
with up-to-date information 
on current clinical studies. 
Section 2.3.1 Known Potential 
Risks; Section 6.1.2 Dosing and 
Administration 
Observation period after dosing 
was clarified and harmonized 
throughout the protocol to 
30 minutes after each SC dose.  
To clarify the observation 
period after each SC dose.  
Section 6.1.2 Dosing and 
Administration 
The study treatment description 
was revised to the following: 
-for the active product, the total 
volume in each vial was removed 
to indicate only the final 
concentration of active product. 
-for the placebo, the volume in 
each vial was reduced from 
1.2 mL to 1 mL. 
The needle position for injection 
was revised to the following: The 
needle is to be injected at a 45- to 
90-degree angle to the skin. 
To revise study treatment 
description of each 
investigational product for 
accuracy and to clarify the 
needle position for injection. 
Section 6.3 Measures to Minimize 
Bias 
The following sentences were 
added: 
In case of emergency unblinding 
of treatment randomization of 
individual subjects, subjects for 
whom the blind has been broken 
will be discontinued from 
treatment at the time of 
unblinding. After discontinuation 
from treatment, subjects should 
remain in the study for the 
duration of the safety follow-up 
period and complete a D281 
(W40) EOS/ET visit 12 weeks 
To clarify the procedure in 
case of subject’s 
discontinuation of study 
treatment due to emergency 
unblinding.  
AnaptysBio, ANB019
IND 136145, SN 0059

Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
Amendment 1 
Protocol ANB019-208 
24 September 2021 
Confidential and proprietary. Permission should be obtained before any reproduction.  
 
8 
Section # and Name 
Description of Change 
Brief Rationale 
after their last dose of study 
treatment. 
Section 6.5 Concomitant Therapy 
Deleted the sentence: The 
concomitant treatments for other 
indications that are not listed in 
the prohibited therapies or 
procedures (Section 6.5.2 must be 
on a stable dose for at least 
4 weeks before study treatment 
administration (Day 1).
This is overly restrictive and 
unnecessary. 
Section 7.2 Subject 
Discontinuation/Withdrawal from 
the Study 
The following sentences were 
edited: In case of early 
withdrawal from the study 
treatment, the subject will be 
required to attend an ET visit at 
the time the decision is made to 
stop study treatment early (see 
the SoA in Section 1.3). After 
completion of the ET visit, the 
subject should then return for a 
final follow up EOS/ET visit 
approximately 12 weeks after 
receiving their last dose of study 
treatment. 
 
Deleted the sentence: Subjects 
withdrawing from the study 
prematurely for reasons other 
than a study treatment-related AE 
may be replaced at the discretion 
of AnaptysBio.
To clarify procedures in case 
of a subject’s early 
withdrawal. 
 
 
 
 
 
 
 
 
 
 
 
 
This sentence was included 
in error as the study is 
adequately powered to allow 
for an anticipated reasonable 
number of early 
terminations. 
Section 8.2.5 Vital Signs 
The measurement of blood 
pressure was modified to be 
performed only once and not 
twice at each specified visit.  
To correct the number of 
blood pressure 
measurements required at 
each specified visit. 
Section 9.3 Populations for 
Analyses, Table 7 
Safety Analysis Set and 
Extension Analysis Set were 
corrected to indicate that at least 
1 dose of imsidolimab or placebo 
is required to be part of this 
population.
To correct the Safety 
Analysis Set to subjects who 
receive at least 1 dose of 
investigational product. 
Section 9.4.5 Analysis of the 
Primary Efficacy Endpoint 
Estimand statement was added. 
To specify the estimand to 
be considered in this study 
for the primary analysis.
Abbreviations; Section 9.4.9 
Pharmacokinetic Analyses; Section 
9.4.9.1 Derivation of 
Pharmacokinetic Parameters; and 
Removed analysis of PK 
parameters and added the 
following note relative to the PK 
analyses: 
To remove analysis of PK 
parameters and to specify 
that NCA is not planned for 
the PK analyses.
AnaptysBio, ANB019
IND 136145, SN 0059

Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
Amendment 1 
Protocol ANB019-208 
24 September 2021 
Confidential and proprietary. Permission should be obtained before any reproduction.  
 
9 
Section # and Name 
Description of Change 
Brief Rationale 
Section 9.4.9.3 Pharmacokinetic 
Parameter Data Analyses 
Due to limited PK sampling, 
noncompartmental analysis 
(NCA) will not be conducted in 
this study. 
Section 9.4.9.5 Immunogenicity 
Analyses 
Added the specification that if 
data permits, potential correlation 
may be analyzed between ADA 
levels, serum concentration, and 
safety and efficacy endpoints and 
removed the following: 
Frequency and percentage of 
ADA response will be presented 
and listed and correlated to 
safety and PK endpoints. 
Added the following note relative 
to the ADA analyses: In addition, 
ADA incidences (overall, 
treatment-emergent, and 
treatment-boosted) will be listed 
and summarized. 
To specify that potential 
correlation may be analyzed 
between ADA levels, serum 
concentration, and safety 
and efficacy endpoints and 
to clarify how data will be 
presented for the ADA 
results.  
Section 11 References 
Added new references to the list 
of references. 
To add new references 
relative to the Fitzpatrick 
skin type classification.
Appendix 1 Contraceptive Guidance 
and Collection of Pregnancy 
Information 
Added tubal ligation in the list of 
effective methods of 
contraception. 
To add tubal ligation in 
addition to tubal occlusion 
to the list of accepted 
methods of contraception. 
Appendix 11 Clinical Laboratory 
Tests 
Removed troponin from the 
biochemistry panel  
Troponin was included 
erroneously. It should not be 
collected routinely for 
imsidolimab Phase 2 trials 
and is not necessary for this 
patient population.
 
AnaptysBio, ANB019
IND 136145, SN 0059

Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
Amendment 1 
Protocol ANB019-208 
24 September 2021 
Confidential and proprietary. Permission should be obtained before any reproduction.  
 
11 
ICH 
International Council for Harmonisation of Technical Requirements for 
Pharmaceuticals for Human Use 
IgG4 
immunoglobulin G4
IHS4 
International Hidradenitis Suppurativa Severity Score System 
IL
interleukin 
IL-36R 
interleukin 36 receptor
IL-36Ra
IL-36 receptor antagonist
IND
Investigational New Drug 
IRB
Institutional Review Board
ITT
intent-to-treat
IUD
intrauterine device
IUS
intrauterine hormone-releasing system
IV
intravenous
IWRS
Interactive Web Response System
KD
dissociation constant 
LSM 
least-squares means
mAb 
monoclonal antibody 
MAD
multiple ascending dose 
MedDRA
Medical Dictionary for Regulatory Activities
min
minute 
MMRM
mixed effects model for repeated measures
mRNA 
messenger ribonucleic acid
NaCl 
sodium chloride
NCA 
noncompartmental analysis
NOAEL
no observed adverse effect level
NRS 
numeric rating scale
PD 
pharmacodynamics
PGIB
Patient Global Impression of Bother  
PGIC
Patient Global Impression of Change
PGIS 
Patient Global Impression of Severity 
PK 
pharmacokinetic(s)
PPP
palmoplantar pustulosis
PRN 
as needed (pro re nata)
PT 
preferred term
QC 
quality control
SAD 
single ascending dose 
SAE 
serious adverse event
SAP
Statistical Analysis Plan 
SC 
subcutaneous(ly)
SD 
standard deviation
SoA
Schedule of Activities 
SOC 
system organ class
SOP
standard operating procedure
t1/2 
terminal half-life 
TB 
tuberculosis 
TEAE
treatment-emergent adverse event
Th-17
T-helper 17 
TK 
toxicokinetic
TNFα 
tumor necrosis factor alpha
AnaptysBio, ANB019
IND 136145, SN 0059

Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
Amendment 1 
Protocol ANB019-208 
24 September 2021 
Confidential and proprietary. Permission should be obtained before any reproduction.  
 
12 
ULN 
upper limit of normal 
URTI
upper respiratory tract infection
W
week
WOCBP 
woman of childbearing potential 
 
 
AnaptysBio, ANB019
IND 136145, SN 0059

Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
Amendment 1 
Protocol ANB019-208 
24 September 2021 
Confidential and proprietary. Permission should be obtained before any reproduction.  
 
14 
6.4 
Study Treatment Compliance ................................................................................................... 56 
6.5 
Concomitant Therapy ............................................................................................................... 56 
 
Permitted Therapies........................................................................................................ 57 
 
Prohibited Medications or Procedures ........................................................................... 57 
6.6 
Rescue Treatment ..................................................................................................................... 58 
6.7 
Dose Modification .................................................................................................................... 59 
6.8 
Treatment After the End of the Study ....................................................................................... 59 
7 
STUDY TREATMENT DISCONTINUATION AND SUBJECT 
DISCONTINUATION/WITHDRAWAL ................................................................................................... 60 
7.1 
Discontinuation of Study Treatment ......................................................................................... 60 
 
Temporary Interruption .................................................................................................. 60 
 
Re-Challenge .................................................................................................................. 60 
7.2 
Subject Discontinuation/Withdrawal from the Study ............................................................... 60 
7.3 
Lost to Follow-Up..................................................................................................................... 61 
8 
STUDY ASSESSMENTS AND PROCEDURES .......................................................................... 62 
8.1 
Efficacy Assessments ............................................................................................................... 62 
 
Pain Numeric Rating Scale ............................................................................................ 62 
 
Patient Global Impression of Severity............................................................................ 63 
 
Patient Global Impression of Bother .............................................................................. 63 
 
Patient Global Impression of Change ............................................................................. 63 
 
Hidradenitis Suppurativa Patient’s Global Assessment ................................................. 63 
 
Dermatology Life Quality Index Questionnaire ............................................................. 63 
 
Hidradenitis Suppurativa Qualty of Life ........................................................................ 64 
 
Hidradenitis Suppurativa Physician’s Global Assesment .............................................. 64 
 
Hurley Stages of Hidradenitis Suppurativa .................................................................... 64 
 
Abscess, Inflammatory Nodule, and Draining Fistula Count ......................................... 64 
 
Hidradenitis Suppurativa Clinical Response .................................................................. 65 
 
International Hidradenitis Suppurativa Severity Score System ..................................... 65 
8.2 
Safety Assessments ................................................................................................................... 65 
 
Adverse Events and Serious Adverse Events ................................................................. 65 
8.2.1.1 
Definition of Adverse Events .............................................................................. 65 
8.2.1.1.1 
Events Meeting the Adverse Event Definition ................................................ 65 
8.2.1.1.2 
Events Not Meeting the Adverse Event Definition ......................................... 66 
8.2.1.2 
Definition of Serious Adverse Events.................................................................. 66 
8.2.1.3 
Classification of an Adverse Event ...................................................................... 67 
8.2.1.3.1 
Severity of Event ............................................................................................. 67 
8.2.1.3.2 
Relationship to Study Treatment ..................................................................... 67 
8.2.1.3.3 
Expectedness .................................................................................................... 68 
8.2.1.4 
Time Period and Frequency for Event Assessment and Follow-Up .................... 68 
8.2.1.5 
Adverse Event Reporting ..................................................................................... 69 
8.2.1.6 
Serious Adverse Event Reporting ........................................................................ 70 
8.2.1.6.1 
Reporting via an Electronic Data Collection Tool ........................................... 71 
8.2.1.6.2 
Reporting via Paper Case Report Form ........................................................... 71 
8.2.1.7 
Reporting Events to Subjects ............................................................................... 71 
8.2.1.8 
Reporting of Pregnancy ....................................................................................... 71 
8.2.1.9 
Treatment of Overdose ........................................................................................ 72 
 
Height and Weight ......................................................................................................... 72 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
AnaptysBio, ANB019
IND 136145, SN 0059

Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
Amendment 1 
Protocol ANB019-208 
24 September 2021 
Confidential and proprietary. Permission should be obtained before any reproduction.  
 
15 
 
Chest X-ray .................................................................................................................... 72 
 
Physical Examinations ................................................................................................... 73 
 
Vital Signs ...................................................................................................................... 73 
 
Electrocardiograms......................................................................................................... 73 
 
Clinical Safety Laboratory Assessments ........................................................................ 73 
8.3 
Other Assessments .................................................................................................................... 74 
 
FITZPATRICK SKIN TYPE CLASSIFICATION ........................................................ 74 
 
Photography ................................................................................................................... 74 
 
Pharmacokinetics ........................................................................................................... 74 
 
Immunogenicity Assessments ........................................................................................ 75 
 
Biomarker Analysis ........................................................................................................ 76 
8.3.5.1 
Tape Stripping...................................................................................................... 76 
8.3.5.2 
Drainage Fluid Collection .................................................................................... 76 
9 
STATISTICAL CONSIDERATIONS ............................................................................................ 77 
9.1 
Statistical Hypotheses ............................................................................................................... 77 
9.2 
Sample Size Determination ...................................................................................................... 77 
9.3 
Populations for Analyses .......................................................................................................... 78 
9.4 
Statistical Analyses ................................................................................................................... 78 
 
General Approach .......................................................................................................... 78 
 
Subject Disposition ........................................................................................................ 79 
 
Baseline Descriptive Statistics ....................................................................................... 79 
 
Concomitant Medication ................................................................................................ 80 
 
Analysis of the Primary Efficacy Endpoint .................................................................... 80 
 
Analysis of the Secondary Efficacy Endpoints .............................................................. 80 
9.4.6.1 
Categorical Endpoints .......................................................................................... 81 
9.4.6.2 
Continuous Endpoints .......................................................................................... 81 
 
Analysis of the Exploratory Endpoints .......................................................................... 81 
 
Safety Analyses .............................................................................................................. 82 
9.4.8.1 
Adverse Events and Serious Adverse Events ...................................................... 83 
9.4.8.2 
12-Lead Electrocardiogram, Vital Signs, and Clinical Safety Laboratory Tests . 83 
 
Pharmacokinetic Analyses ............................................................................................. 84 
9.4.9.1 
Derivation of Pharmacokinetic Parameters ......................................................... 84 
9.4.9.2 
Pharmacokinetic Concentration Data Analysis ................................................... 84 
9.4.9.3 
Pharmacokinetic Parameter Data Analysis .......................................................... 84 
9.4.9.4 
Population Pharmacokinetics Analysis ................................................................ 84 
9.4.9.5 
Immunogenicity Analyses ................................................................................... 85 
 
Biomarker Analyses ....................................................................................................... 85 
 
Planned Interim Analysis ............................................................................................... 85 
10 
SUPPORTING DOCUMENTATION AND OPERATIONAL CONSIDERATIONS .................. 86 
10.1 
Regulatory, Ethical, and Study Oversight Considerations........................................................ 86 
 
Informed Consent Process .............................................................................................. 86 
10.1.1.1 
Consent and Other Informational Documents Provided to Subjects ................... 86 
10.1.1.2 
Consent Procedures and Documentation ............................................................. 86 
 
Study Discontinuation and Closure ................................................................................ 87 
 
Confidentiality and Privacy ............................................................................................ 87 
 
Future Use of Stored Specimens and Data ..................................................................... 88 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
AnaptysBio, ANB019
IND 136145, SN 0059

Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
Amendment 1 
Protocol ANB019-208 
24 September 2021 
Confidential and proprietary. Permission should be obtained before any reproduction.  
 
16 
 
Medical Monitor ............................................................................................................. 88 
 
Safety Oversight ............................................................................................................. 89 
 
Clinical Monitoring ........................................................................................................ 89 
 
Quality Assurance and Quality Control ......................................................................... 90 
 
Data Handling and Record Keeping ............................................................................... 90 
10.1.9.1 
Data Collection and Management Responsibilities ............................................. 90 
10.1.9.2 
Study Records Retention ..................................................................................... 92 
 Protocol Deviations ........................................................................................................ 92 
 Publication and Data Sharing Policy .............................................................................. 93 
 Conflict of Interest Policy .............................................................................................. 93 
10.2 
Additional Considerations ........................................................................................................ 94 
 
Ethics and Responsibility ............................................................................................... 94 
 
Amendment Policy ......................................................................................................... 94 
 
Insurance ........................................................................................................................ 94 
11 
REFERENCES ................................................................................................................................ 95 
12 
APPENDICES ................................................................................................................................. 97 
Appendix 1: Contraceptive Guidance and Collection of Pregnancy Information ................................. 97 
Appendix 2: Pain Numerical Rating Scales ......................................................................................... 101 
Appendix 3: Patient Global Impression of Severity ............................................................................ 102 
Appendix 4: Patient Global Impression of Bother ............................................................................... 103 
Appendix 5: Patient Global Impression of Change ............................................................................. 104 
Appendix 6: Hidradenitis Suppurativa Patient’s Global Assessment .................................................. 105 
Appendix 7: Dermatology Life Quality Index ..................................................................................... 106 
Appendix 8: Hidradenitis Suppurativa Quality of Life........................................................................ 108 
Appendix 9: Hidradenitis Suppurativa Physician’s Global Assessment ............................................. 109 
Appendix 10: International Hidradenitis Suppurativa Severity Score System .................................... 110 
Appendix 11: Clinical Laboratory Tests .............................................................................................. 111 
Appendix 12: Fitzpatrick Skin Type Classification ............................................................................. 113 
 
 
 
 
 
 
 
 
 
 
 
 
AnaptysBio, ANB019
IND 136145, SN 0059

Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
Amendment 1 
Protocol ANB019-208 
24 September 2021 
Confidential and proprietary. Permission should be obtained before any reproduction.  
20 
The treatment arms during the placebo-controlled period will be as follows:  
1. Imsidolimab 400 mg on Day 1, followed by 200 mg on Days 29, 57, and 85  
2. Imsidolimab 200 mg on Day 1, followed by 100 mg on Days 29, 57, and 85  
3. Placebo on Days 1, 29, 57, and 85 
During the extension period, all subjects will receive imsidolimab, SC 
administered on 4 occasions: Day 113 (Week 16), Day 141 (Week 20), Day 169 
(Week 24), and Day 197 (Week 28). Subjects randomized to imsidolimab during 
the placebo-controlled period will continue to receive the same dose of 
imsidolimab on Days 113, 141, 169, and 197. Subjects randomized to placebo 
during the placebo-controlled period will receive either a 400-mg dose of 
imsidolimab on Day 113, followed by a 200-mg dose of imsidolimab on Days 
141, 169, and 197, or 200-mg dose of imsidolimab on Day 113, followed by a 
100-mg dose of imsidolimab on Days 141, 169, and 197 based on a 1:1 
randomization.  
For scheduled on-site study visits, subjects will come to the study site on 
12 occasions: screening and Days 1, 29, 57, 85, 113, 141, 169, 197, 225, 253, and 
281 (End of Study [EOS]/Early Termination [ET]). All procedures will be 
conducted in accordance with the Schedule of Activities (SoA) in Section 1.3. 
Disease activity will be evaluated for all subjects using AN count, draining fistula 
count, Hidradenitis Suppurativa Clinical Response 50 (HiSCR50) (a responder 
HiSCR50 is defined as a subject with at least a 50% decrease in AN count from 
Baseline with no increase in abscess count and no increase in draining fistula 
count relative to Baseline), Hidradenitis Suppurativa Clinical Response 75 
(HiSCR75) (a responder HiSCR75 is defined as a subject with at least a 75% 
decrease in AN count from Baseline with no increase in abscess count and no 
increase in draining fistula count relative to Baseline), Hurley Stage, Hidradenitis 
Suppurativa Physician’s Global Assessment (HS-PGA), International Hidradenitis 
Suppurativa Severity Score System (IHS4), HS Pain Numeric Rating Scale (NRS), 
Patient Global Impression of Change (PGIC), Patient Global Impression of 
Severity (PGIS), Patient Global Impression of Bother (PGIB), Dermatology Life 
Quality Index (DLQI), Hidradenitis Suppurativa Quality of Life (HiSQoL), and 
Hidradenitis Suppurativa Patient’s Global Assessment (HS-PtGA).  
Safety assessments will include adverse event (AE)/serious adverse event (SAE) 
monitoring, vital signs, physical examination, electrocardiograms (ECGs), and 
clinical laboratory tests (hematology, biochemistry, and urinalysis). 
AnaptysBio, ANB019
IND 136145, SN 0059

Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
Amendment 1 
Protocol ANB019-208 
24 September 2021 
Confidential and proprietary. Permission should be obtained before any reproduction.  
21 
Blood samples will be collected during the study to determine pharmacokinetics 
(PK) and immunogenicity (presence of anti-drug antibodies [ADA] to 
imsidolimab) on Day 1 before the administration of the study treatment and at 
other time points specified in the SoA (Section 1.3). Any remaining serum/plasma 
from samples collected for PK/pharmacodynamic (PD) immunogenicity endpoints 
may be retained for assay method development, troubleshooting, or validation. 
The samples will not be used for any type of genetic analyses.  
Photography is an optional procedure for all subjects at each of the specified visits 
at selected sites.   
Skin tape strips will be collected at Day 1, Week 4, Week 16, and Week 32 to 
study gene expression.  
Interim analyses (IA) may be performed for assessment of all primary and 
secondary efficacy endpoints and evaluation of all safety data available.  
Objectives: 
Primary Objective:   
 To evaluate the efficacy of imsidolimab in subjects with HS  
 
Secondary Objectives:  
 To evaluate the safety of imsidolimab in subjects with HS 
 To evaluate the effect of imsidolimab on HS signs and symptoms in 
subjects with HS 
Exploratory Objectives: 
 To further evaluate the effect of imsidolimab on HS signs and symptoms, 
and quality of life in subjects with HS 
 To explore the effect of imsidolimab on cutaneous biomarkers 
 To test for immunogenicity to imsidolimab 
 To describe the PK profile of imsidolimab in subjects with HS 
Endpoints: 
Primary Endpoint: 
 Change from Baseline in AN count at Week 16 
 
Secondary Efficacy Endpoints:  
 Percent change from Baseline in AN count at Week 16 
 Proportion of subjects achieving HiSCR50 at Week 16 
 Change from Baseline in HS Pain NRS at Week 16 
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 Percent change from Baseline in HS Pain NRS at Week 16  
Safety Endpoint: 
 Incidence of AEs, SAEs, and AEs leading to treatment discontinuation, as 
well as changes in vital signs, clinical laboratory parameters (hematology, 
biochemistry, and urinalysis), and 12-lead ECGs 
Exploratory Endpoints:  
 Change from Baseline in AN count at visits other than Week 16 
 Percent change from Baseline in AN count at visits other than Week 16 
 Proportion of subjects achieving a reduction in AN count of ≥50% and 
≥75% relative to Baseline (AN50 and AN75 responses)  
 Percentage of subjects experiencing flare, defined as a ≥25% increase in 
AN count with an absolute increase in AN count of ≥2 relative to Baseline 
at each visit 
 Change from Baseline in abscess count at each visit  
 Change from Baseline in inflammatory nodule count at each visit 
 Change from Baseline in draining fistula count at each visit 
 Proportion of subjects achieving HiSCR50 at visits other than Week 16 
 Proportion of subjects achieving HiSCR75 at each visit 
 Proportion of subjects achieving 0 (inactive) or 1 (almost inactive) on 
HS-PGA at each visit 
 Proportion of subjects with ≥2-point reduction from Baseline on HS-PGA 
at each visit 
 Change from Baseline in HS-PGA 
 Change from Baseline in calculated composite of abscesses, draining 
fistulas, and inflammatory and non-inflammatory nodules 
 Change from Baseline in HS Pain NRS at visits other than Week 16 
 Percent change from Baseline in HS Pain NRS at visits other than Week 16 
 Proportion of subjects achieving a ≥3-point reduction on the HS Pain NRS 
for subjects with Baseline HS Pain NRS of at least 3 
 Proportion of subjects requiring rescue medication or treatment at each 
visit 
 Change from Baseline in DLQI score at each visit 
 Change from Baseline in IHS4 at each visit 
 Change from Baseline in HiSQoL at each visit 
 Change from Baseline in HS-PtGA at each visit 
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 Proportion of subjects in each response category for the HS-PtGA at each 
visit 
 Proportion of subjects in each response category for the PGIC at each visit 
 Proportion of subjects achieving improvement (“Much better” or “Very 
much better”) according to the PGIC at each visit 
 Proportion of subjects achieving improvement (“A little better”, “Much 
better” or “Very much better”) according to the PGIC at each visit 
 Proportion of subjects in each response category for the PGIB at each visit 
 Change from Baseline in PGIB at each visit 
 Proportion of subjects achieving “A little bothered” or “Not at all 
bothered” for the PGIB at each visit 
 Proportion of subjects in each response category for the PGIS at each visit 
 Proportion of subjects achieving “Mild” or “No activity” according to the 
PGIS at each visit 
 Change from Baseline in PGIS at each visit 
 Proportion of subjects in each category of Hurley Stage at each visit 
 Change from Baseline in Hurley Stage at Weeks 16, 32, and 40  
 Proportion of subjects achieving at least a 1-stage improvement in Hurley 
Stage 
 Skin tape strip and drainage fluid biomarkers analysis including, but not 
limited to, IL-36 and Th-17 
 Presence of ADAs to imsidolimab 
 Serum concentration following imsidolimab administration and other 
parameters as appropriate will be determined to describe the PK profile of 
imsidolimab 
Study 
Population: 
Approximately 120 male and female subjects aged 18 to 75 years with clinically 
confirmed diagnosis of HS 
Inclusion 
Criteria: 
1. Male or female aged 18 to 75 years (inclusive) at the time of signing informed 
consent. 
2. Clinically confirmed diagnosis of active HS with a disease duration of ≥ 6 
months before Day 1 as determined by the Investigator through subject 
interview and/or review of the medical history. 
3. HS lesions present in at least 2 distinct anatomical areas, 1 of which must be 
Hurley Stage II (ie, single or multiple, widely separated, recurrent abscesses 
with tract formation and cicatrization) or Hurley Stage III (ie, diffuse or near-
diffuse involvement, or multiple interconnected tracts and abscesses across 
the entire area). 
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4. Total AN count ≥ 5 
5. Draining fistulas ≤ 20. 
6. Stable HS for at least 6 weeks prior to Day 1 visit as determined by the 
Investigator through subject interview and review of medical history. 
7. Agree to daily use (and throughout the study) of one of the following over-
the-counter topical treatments on their body areas affected with HS lesions: 
chlorhexidine gluconate, triclosan, benzoyl peroxide, dilute bleach in 
bathwater, or soap and water.  
8. Meet the following laboratory criteria at screening: 
a) Hemoglobin ≥ 90 g/L (≥ 9 g/dL) 
b) White blood cell count ≥ 3.0 × 109/L (≥ 3.0 × 103/µL) 
c) Platelets ≥ 100 × 109/L (≥ 100 × 103/µL) 
d) Serum creatinine < 132.6 µmol/L (< 1.5 mg/dL) 
e) Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 
2 upper limit of normal (ULN) 
f) Total bilirubin ≤ 1.5 × ULN. Subjects with known Gilbert’s disease who 
have serum bilirubin < 3 × ULN may be included 
9. Body weight ≥ 40 kg.  
10. Contraceptive use by men and women should be consistent with local 
regulations regarding the methods of contraception for subjects participating 
in clinical studies. 
Contraception and Pregnancy: 
a) A male subject who has not had a vasectomy must agree to use 
contraception as detailed in Appendix 1 of this protocol during the 
treatment period and for at least 220 days (which includes the duration of 
relevant exposure plus the duration of sperm cycle) after the last study 
treatment administration and refrain from donating sperm during this 
period. 
b) Female subjects: 
i) A woman of childbearing potential (WOCBP) is eligible to 
participate if she has a negative serum pregnancy test (β-human 
chorionic gonadotropin) at screening and a negative urine pregnancy 
test at Day 1 (see Appendix 1), is not breastfeeding, and agrees to 
follow the contraceptive guidance in Appendix 1 during the treatment 
period and for at least 6 months after receiving the study treatment, 
and refrains from donating oocytes for assisted reproduction during 
this period. The female subject’s selected form of contraception must 
be effective by the time the female subject enters into the study at 
Day 1 (eg, hormonal contraception should be initiated at least 12 
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Weeks before Day 1. For WOCBP, hormonal contraceptives must be 
used without schedule changes and in steady doses during the study 
treatment. Starting hormonal contraceptives during the study is not 
permitted. Use of any hormonal contraceptives containing 
drospirenone, chlormadinone acetate, or cyproterone acetate is 
prohibited unless part of a stable contraceptive regimen as described 
in Section 6.5.1. 
ii) A woman not of childbearing potential as defined in Appendix 1 is 
eligible to participate in the study. A postmenopausal woman must 
have a follicle -stimulating hormone (FSH) test confirming 
nonchildbearing potential. 
11. Willing to participate and capable of giving written informed consent, which 
must be personally signed and dated by the subject and obtained prior to any 
trial-related activities.  
12. Willing to comply with all study procedures and available for the duration of 
the study. 
Exclusion 
Criteria: 
1. Concomitant dermatological or medical conditions that may interfere with the 
Investigators’ ability to evaluate the subject’s response to therapy. 
2. History of clinically significant (as determined by the Investigator) cardiac, 
pulmonary, neurologic, gastrointestinal, endocrine, hematological, renal, 
hepatic, cerebral or psychiatric disease, or other major uncontrolled disease. 
3. Chronic or recurrent infectious disease, including but not limited to upper and 
lower respiratory infection (eg, bronchiectasis), urinary tract infection (eg, 
recurrent pyelonephritis), within 6 months prior to screening. Note: A subject 
with a history of localized oral or genital herpes simplex that, in the opinion 
of the Investigator, is well controlled will be eligible for study participation. 
4. Any evidence of active infection that required treatment with a systemic 
antibiotic, antiviral, or antifungal agent within 4 weeks of Day 1 
(eg, bronchopulmonary, urinary, or gastrointestinal), excluding localized oral 
or genital herpes simplex that, in the opinion of the Investigator, is well-
controlled. 
5. Any factors that would predispose the subject to develop an infection in the 
Investigator’s opinion. 
6. Opportunistic infection (eg, Pneumocystis carinii, aspergillosis, or 
mycobacteria other than tuberculosis [TB]) or parasitic infections (eg, 
helminths, protozoa, Trypanosoma cruzi) within 6 months prior to screening. 
7. Herpes zoster infection within 2 months prior to screening. 
8. [intentionally blank] 
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9. Known or suspected congenital or acquired immunodeficiency state, or 
condition that would compromise the subject’s immune status (eg, history of 
splenectomy). 
10. Major surgery within 4 weeks of Day 1. 
11. History of cancer or lymphoproliferative disease within 5 years of Day 1. 
Subjects with successfully treated nonmetastatic cutaneous squamous cell or 
basal cell carcinoma and/or localized carcinoma in situ of the cervix are not to 
be excluded. 
12. History of any significant drug allergy or reaction to polysorbate-20, a 
component of imsidolimab formulation, or the inactive ingredients 
(excipients). 
13. Any systemic antibiotic treatment for HS within 4 weeks of Day 1. 
14. Prescription topical therapies for the treatment of HS within 2 weeks of 
Day 1. 
15. Over-the-counter topical antiseptic washes, creams, soaps, ointments, gels, 
and liquids containing antibacterial agents to treat HS within 2 weeks prior to 
Day 1 (unless specified as permitted in Section 6.5.1) 
16. Systemic non-biologic therapies with potential therapeutic impact for HS 
within 4 weeks of Day 1, including methotrexate (MTX), cyclosporine, 
retinoids, and fumaric acid esters, and oral or injectable corticosteroids 
(unless clearly specified as permitted; see Section.6.5.1). 
17. Oral analgesics (including opioids) within 2 weeks of Day 1, unless a subject 
is on a stable dose (as needed [PRN] is not considered a stable dose) of non-
opioid analgesics for a non-HS medical condition (eg, osteoarthritis), and is 
stable for 2 weeks prior to Baseline and is anticipated to remain stable 
throughout study participation.  
18. Subject requires or is expected to require opioid analgesics during the study 
for any reason (excluding tramadol as described in Section 6.5.1). 
19. Nonbiologic investigational drug within 4 weeks or 5 half-lives of Day 1, 
whichever is longer.  
20. Biologics for at least 12 weeks or 5 half-lives prior to Day 1 (eg, 
adalimumab). 
21. Live or live-attenuated vaccines within 12 weeks prior to Day 1. Live and 
live-attenuated vaccines may be utilized 12 weeks after the last study 
treatment administration. Note: Currently authorized nonlive and nonlive-
attenuated vaccines for Coronavirus Disease 2019 (COVID-19) (eg, RNA-
based vaccines, protein-based vaccines, and nonreplicating viral vector-based 
vaccines) are allowed during the study. 
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Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
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22. Surgical, laser, or intense pulsed light (IPL) intervention in area with HS 
lesion within 4 weeks prior to Day 1. 
23. Phototherapy (psoralen and ultraviolet A [PUVA] and/or UVB) within 4 
weeks prior to Day 1 
24. Active TB or latent TB infection as indicated by a positive 
QuantiFERON®-TB Gold test at screening (if the test is indeterminate, it can 
be repeated only once), chest X-ray, and/or clinical examination, or has had 
active TB disease at any time in the past. 
25. Clinically significant drug or alcohol abuse in the last year prior to Day 1, or 
other factors limiting the ability to cooperate and to comply with the study 
protocol, as determined by the Investigator. 
26. Subject is a pregnant or lactating woman, or a woman who intends to become 
pregnant during the study period. 
27. Any other physical, mental, or medical conditions, which, in the opinion of 
the Investigator, make study participation inadvisable or could confound 
study assessments. 
28. Clinically significant abnormality on chest X-ray at screening or within 6 
months prior to screening. 
29. Positive blood screen for hepatitis C antibody and hepatitis C RNA, 
antibodies to hepatitis B core antigen, hepatitis B surface antigen, or human 
immunodeficiency virus 1 and 2 antibodies. 
30. Subject is not able to tolerate SC drug administration. 
Phase: 
2 
Study 
Centers 
Enrolling 
Subjects: 
Approximately 40 study sites are expected to participate in this study.   
Description 
of Study 
Treatments: 
Imsidolimab (ANB019) will be provided in a glass vial as a sterile, colorless to 
yellow, and clear to slightly opalescent solution for injection. The placebo 
contains no active ingredient and will be provided as a sterile, colorless to slightly 
yellowish, and clear to very slightly opalescent solution for injection. 
Imsidolimab will be administered as SC injection. Placebo will also be 
administered as SC injection in the same volumes as imsidolimab. 
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Rescue 
Treatments: 
Criteria for use of rescue treatments and permitted rescue treatments are further 
described in Section 6.6 of the protocol. 
Subject 
Duration: 
The maximum study duration per subject included in this study is approximately 
44 weeks from first visit to last visit.  
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i The FSH testing is performed for women not of childbearing potential who are postmenopausal (at least 12 months of amenorrhea without an alternative 
medical cause). Additional pregnancy testing may be performed whenever a menstrual cycle is missed or when pregnancy is otherwise suspected. Refer to 
Appendix 11 for details and instructions regarding clinical laboratory parameters. 
j Refer to Section 8.1 for details and instructions on AN count, draining fistula count, HiSCR, Hurley Stage, HS-PGA, IHS4, HS Pain NRS, PGIC, PGIB, PGIS, 
DLQI, HS-PtGA, and HiSQoL. From screening through Week 32, subjects will not be permitted to use any analgesics related to HS pain within 24 hours of a 
scheduled study visit. Subjects may use analgesics after the questionnaires are completed at the study visit.  
k Sample for PK will be collected predose. See Table 5 for PK and ADA sample collection time points. 
l Tape stripping will be performed for all randomized subjects as part of this study (not optional). Tape strips will be collected from non-lesional and lesional 
skin at Day 1 and Week 16 and from lesional skin at Week 4 and Week 32. Drainage fluid may be collected (optional) at any visit after screening in which HS 
lesional drainage is present, and stored for future biomarker analysis. 
m Photography (of representative lesion[s], fistulas, and scarring) is an optional procedure for all subjects at each of the specified visits at selected site. Two 
images from two distinct regions of highest density inflammatory nodules/abscesses/fistulas should be taken at baseline if possible. The anatomic regions 
should be identifiable from the images. These regions should be recorded and consistently photographed throughout the duration of the study if possible. 
n Starting at Day 113 (Week 16), subjects who received placebo during the placebo-controlled period will be randomized 1:1 to receive imsidolimab at 1 of 
2 different regimens. Subjects who received imsidolimab during the placebo-controlled period will not be randomized at the Week 16 visit. 
o During the placebo-controlled period, subjects will receive either imsidolimab or placebo SC administered as follow according to randomization arm:1) 
400-mg dose of imsidolimab on Day 1; followed by 200-mg dose of imsidolimab on Days 29, 57, and 85; 2) 200-mg dose of imsidolimab on Day 1; followed 
by a 100-mg dose of imsidolimab on Days 29, 57, and 85; 3) placebo. The placebo-controlled period ends at the Day 113 (Week 16) visit, before study 
treatment administration. During the extension period, subjects assigned to imsidolimab during the placebo-controlled period will continue to receive the same 
maintenance dose of imsidolimab, 200 mg or 100 mg. Subjects assigned to placebo during the placebo-controlled period will receive either a 400-mg dose of 
imsidolimab on Day 113, followed by 200-mg doses of imsidolimab on Days 141, 169, and 197; or a 200 mg dose of imsidolimab on Day 113, followed by 
100-mg doses of imsidolimab on Days 141, 169, and 197. 
p At screening, prior medications should be reviewed and documented. Refer to Section 6.5.
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38 
study were generally well tolerated with a similar number of treatment-emergent adverse events 
(TEAEs) reported in subjects receiving imsidolimab or placebo, 29 subjects (81%) and 11 
subjects (92%), respectively. The most frequently reported AEs were upper respiratory tract 
infection (URTI; 10 [28%] imsidolimab; 6 [50%] placebo), headache (10 [28%] imsidolimab; 
3 [25%] placebo), and viral URTI (4 [11%] imsidolimab; 1 [8%] placebo). Additionally, multiple 
doses of imsidolimab up to 300 mg administered by IV infusion once weekly for 4 weeks to 
18 healthy adults were also well tolerated. Overall, TEAEs occurred in 16 subjects (89%) 
receiving imsidolimab and in 3 subjects (50%) receiving the placebo. The most common AEs 
were headache (7 [39%] imsidolimab; 1 [17%] placebo) and URTI (3 [17%] imsidolimab; 1 
[17%] placebo). 
In ANB019-005, single doses of imsidolimab up to 750 mg administered by IV infusion or SC 
injection to 32 healthy Japanese and Caucasian adults were generally well tolerated. The most 
common TEAEs were alanine aminotransferase (ALT) increased (3 subjects [9.4%]) and 
aspartate aminotransferase (AST) increased (2 subjects [6.3%]).  
One serious adverse event (SAE) of sepsis was reported in the recently completed ANB019-002 
study in subjects with GPP; the SAE was considered possibly related to the study drug. The 
subject had a medical history of sepsis and experienced the SAE after the 750 mg IV dose 
administration. Antibiotic treatment rapidly resolved the sepsis episode with complete subject 
recovery. A second SAE of COVID-19 infection which was unrelated to imsidolimab was also 
reported. Further details of imsidolimab clinical studies are in the IB. 
As allergic or anaphylactic reactions may occur in any subjects treated with mAbs, subjects 
should be observed during study drug administration and for a period of 30 minutes after each 
SC drug administration. Subjects with true allergic/anaphylactic reactions should not receive 
further doses of the monoclonal antibody. Symptoms of an apparent allergic reaction to the drug, 
also known as ‘cytokine release syndrome’, vary dramatically but can include:  
 Mild to moderate fever, chills, headache, nausea, and vomiting 
 Moderate to severe symptoms such as edema, hypotension, and pulmonary infiltrates (eg, 
blood and mucus in the lung) 
Such reactions should be managed as clinically indicated and according to standard clinical 
practice. 
 
KNOWN POTENTIAL BENEFITS  
Subjects with HS may or may not receive direct benefit from participating in this study. An 
improvement in the condition as a result of participating in the study may be observed since all 
subjects will receive the active treatment at some point during the study.  
Participation in this study also may help generate future benefit for larger groups of patients with 
HS if imsidolimab proves to be successful in treating this disease.  
 
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Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
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39 
 
ASSESSMENT OF POTENTIAL RISKS AND BENEFITS  
All quality, pharmacology and toxicology data, and satisfactory safety and tolerability data 
demonstrated in nonclinical and clinical studies are considered sufficient to expect a positive 
benefit/risk ratio for the treatment of HS with imsidolimab, and therefore to initiate this study. 
The risk to subjects in this trial will be minimized by compliance with the eligibility criteria, 
proper study design, and close monitoring. 
 
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46 
subject is suspected of having been or is currently infected with COVID-19, the on-site 
visit should either be re-scheduled or a virtual visit may be performed, as applicable. 
 In the event that a subject cannot attend their regularly scheduled study visits in person due 
to COVID-19 necessitating a limit on in-person contact, the Investigator may perform 
safety and efficacy assessments by phone or video, with home nursing visit support for 
procedures that cannot be done virtually. The Investigator may use the technology platform 
that is currently available to them. Suggested platforms include Apple FaceTime, Zoom for 
Healthcare, Facebook Messenger video chat, Microsoft Team, Google Hangouts video, and 
Skype. Home nursing visit support may be used in addition to phone or video at visits that 
require procedures that cannot be done via phone or video alone, such as but not limited to, 
ECG, PK draws, clinical laboratory draws, study drug administration. The home nurse will 
collect the lab samples and perform all applicable study assessments that are possible 
during a home visit, including collection of adverse events and concomitant medications. 
During the COVID period, if any data is collected at a home visit, it will be recorded by 
the home nurse in the source documents and the originals will be sent back to the site for 
data entry into the electronic data capture system for storage/archiving. 
 Clinical laboratory tests (chemistry and hematology) and pregnancy tests may be 
performed by local laboratory if home nursing visits are not possible and sample collection 
cannot be performed at the study site due to COVID 19-related limitations, including but 
not limited to site closure. Abnormal laboratory results should be promptly communicated 
to the Medical Monitor. Subjects’ anonymity must be maintained when communicating 
results to the Medical Monitor.   
 At home study drug administration by home health nurses may be done. 
 Source documentation should note that the visit was performed virtually (not face-to-face), 
and note the name of the local laboratory where laboratory tests were done. 
 If certain study procedures or assessments cannot be completed per the schedule of events, 
the reason for the missed assessment (ie, laboratory, vital signs, physical exams, etc.) must 
be noted in the source documentation (eg, COVID-19), captured in the protocol deviations 
documentation, and reported to the IRB/Ethics Committee, as applicable. 
A detailed assessment of COVID-19 related risk and mitigation measures will be documented in 
the appropriate study plans. 
 
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49 
3. 
Chronic or recurrent infectious disease, including but not limited to upper and lower 
respiratory infection (eg, bronchiectasis), urinary tract infection (eg, recurrent 
pyelonephritis), within 6 months prior to screening. Note: A subject with a history of 
localized oral or genital herpes simplex that, in the opinion of the Investigator, is well 
controlled will be eligible for study participation. 
4. 
Any evidence of active infection that required treatment with a systemic antibiotic, antiviral, 
or antifungal agent within 4 weeks of Day 1 (eg, bronchopulmonary, urinary, or 
gastrointestinal), excluding localized oral or genital herpes simplex that, in the opinion of 
the Investigator, is well-controlled. 
5. 
Any factors that would predispose the subject to develop an infection in the Investigator’s 
opinion. 
6. 
Opportunistic infection (eg, Pneumocystis carinii, aspergillosis, or mycobacteria other than 
tuberculosis [TB]) or parasitic infections (eg, helminths, protozoa, Trypanosoma cruzi) 
within 6 months prior to screening. 
7. 
Herpes zoster infection within 2 months prior to screening. 
8. 
[intentionally blank] 
9. 
Known or suspected congenital or acquired immunodeficiency state, or condition that would 
compromise the subject’s immune status (eg, history of splenectomy). 
10. Major surgery within 4 weeks of Day 1. 
11. History of cancer or lymphoproliferative disease within 5 years of Day 1. Subjects with 
successfully treated nonmetastatic cutaneous squamous cell or basal cell carcinoma and/or 
localized carcinoma in situ of the cervix are not to be excluded. 
12. History of any significant drug allergy or reaction to polysorbate-20, a component of 
imsidolimab formulation, or the inactive ingredients (excipients). 
13. Any oral antibiotic treatment for HS within 4 weeks of Day 1. 
14. Prescription topical therapies for the treatment of HS within 2 weeks of Day 1. 
15. Over-the-counter topical antiseptic washes, creams, soaps, ointments, gels, and liquids 
containing antibacterial agents to treat HS within 2 weeks prior to Day 1 (unless specified as 
permitted in Section 6.5.1) 
16. Systemic non-biologic therapies with potential therapeutic impact for HS within 4 weeks of 
Day 1, including methotrexate (MTX), cyclosporine, retinoids, and fumaric acid esters, and 
oral or injectable corticosteroids (unless clearly specified as permitted; see Section.6.5.1). 
17. Oral analgesics (including opioids) within 2 weeks of Day 1, unless a subject is on a stable 
dose (PRN is not considered a stable dose) of non-opioid analgesics for a non-HS medical 
condition (eg, osteoarthritis), and the is stable for 2 weeks prior to Baseline and is 
anticipated to remain stable throughout study participation.  
18. Subject requires or is expected to require opioid analgesics during the study for any reason 
(excluding tramadol as described in Section 6.5.1). 
19. Nonbiologic investigational drug within 4 weeks or 5 half-lives of Day 1, whichever is 
longer.  
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53 
Study Treatment 
Name: 
Imsidolimab (ANB019) 
Anti-interleukin 36 receptor 
monoclonal antibody 
Placebo 
 
dilution is required. Syringes should be covered in tape by an unblinded pharmacist to 
obscure color and volume. 
The preferred anatomical site of SC administration is the abdomen; however, the injection 
may be made in the upper arm, if needed. 
A 30-minute observation period should be included after each SC dose administered. 
The same anatomical site should be used throughout the entire study for a given subject (ie, 
do not administer one dose into the upper arm and at a subsequent visit or dose, administer 
the next dose into the abdomen). 
Subsequent doses should be rotated within an anatomical site (ie, if the upper left 
abdominal quadrant is used as the initial site of administration, then the next administration 
at a subsequent visit should be rotated to the upper right quadrant). 
Subcutaneous injections should not be given into moles, scars, tattoos, or areas where the 
skin is tender, bruised, red, hard, or not intact. 
Prior to SC needle insertion, the skin will be pinched between the thumb and index finger 
to separate the subcutaneous layer from the muscle. 
The needle is to be injected at a 45- to 90-degree angle to the skin. 
The plunger will be pressed gently until the entire dose is delivered to the SC space and the 
needle will be held in place (fully depressed) for 10 seconds after the injection is 
administered.  
The needle will be removed and then the skin pinch released; any leakage or backflow of 
fluid from the administration site onto the surface of the skin will be noted and documented 
in the eCRF. 
The site of administration is NOT to be massaged by either the clinic staff or by the subject 
for at least 60 minutes after drug administration. 
Abbreviations: eCRF, electronic case report form; NaCl, sodium chloride; SC, subcutaneous. 
The contents of the label will be in accordance with all applicable regulatory requirements. 
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estimated to be a sufficient period after the last dose administration when a live or live-attenuated 
vaccine can be safety administered. 
The Medical Monitor should be contacted if there are any questions regarding concomitant or 
prior therapy. 
 
PERMITTED THERAPIES 
Use of daily washes are required for all subjects participating in the study.  Permitted washes are 
limited to chlorhexidine gluconate, triclosan, benzoyl peroxide, dilute bleach in bathwater, or 
soap and water.  
Starting on Day 1 and if a subject’s pain worsens, subjects that require analgesia will be allowed 
to use ibuprofen (at a dose of up to 800 mg po every 6 hours, not to exceed 3.2 grams/24 hours) 
and/or acetaminophen as per local labeling. Pain uncontrolled with ibuprofen/acetaminophen 
may be controlled with tramadol (at a dose of up to 100 mg po every 4 hours, not to exceed 
400 mg/24 hours) after Investigator discussion with the Medical Monitor). Of note, dose 
adjustments of ibuprofen, acetaminophen, or tramadol, and use of these analgesics PRN up to the 
maximum permitted dose and frequency, are allowed during the study. From screening through 
Week 32, subjects will not be permitted to use any analgesics related to HS pain within 24 hours 
of a scheduled study visit. 
Oral contraceptives should be continued if stable for the last 12 weeks before Day 1 and if stable 
in dose and dosing regimen and type (brand) and if the subject plans to continue throughout the 
study period. 
Currently authorized nonlive and nonlive-attenuated vaccines, including those for COVID-19 (eg, 
RNA-based vaccines, protein-based vaccines, and nonreplicating viral vector-based vaccines), are 
allowed during the study. If it is unclear if a vaccine is permitted, the Medical Monitor should be 
consulted prior to subjects’ receiving a vaccine. Of note, vaccines, including those for COVID-19, 
should be captured as a concomitant medication and any related symptoms documented as AEs. 
All permitted medications should be recorded as concomitant medications. 
The Medical Monitor should be notified if a subject receives antibiotics for more than 10 days 
for adverse events. 
 
PROHIBITED MEDICATIONS OR PROCEDURES 
Prohibited medications/therapy are listed below in Table 4. The use of a prohibited 
medication/therapy (unless conditions for use of rescue medications have been met, see 
Section 6.6) is a protocol violation and must be recorded in the eCRF. Subjects who receive 
prohibited rescue treatment will be discontinued from the study and should return for a final ET 
visit 12 weeks after their last dose. Study procedures at the ET visit should be completed 
according to the SoA in Section 1.3. In the case of ongoing AEs/SAEs, the subject should be 
followed up until it has resolved to a stable outcome or subject is lost to follow-up. The date and 
time of rescue medication administration, as well as the name and dosage regimen of the rescue 
medication, must be recorded into the eCRF/study database by study site personnel. 
 
 
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PATIENT GLOBAL IMPRESSION OF SEVERITY  
The PGIS will be assessed at the visits specified in the SoA (Section 1.3). It is a single-item 
question, which asks the subject to rate the current severity of their symptoms. The response 
options are “No activity”, “Mild”, “Moderate”, “Severe”.  
The PGIS will be completed by the subject on a worksheet prior to any safety and efficacy 
evaluations. The questionnaire is self-explanatory and handed to the subject who is asked to fill it 
in without the need for a detailed explanation. The PGIS (modified from Yalcin 2003) is 
presented in Appendix 3. 
 
PATIENT GLOBAL IMPRESSION OF BOTHER 
The PGIB will be assessed at the visits specified in the SoA (Section 1.3). It is a single-item 
questionnaire, which asks the subject to rate how bothered they are by the signs and symptoms of 
HS.  
The PGIB will be completed by the subject on a worksheet prior to any safety and efficacy 
evaluations. The questionnaire is self-explanatory and handed to the subject, who is asked to fill 
it in without the need for a detailed explanation. The PGIB (modified from Yalcin 2003) is 
presented in Appendix 4. 
 
PATIENT GLOBAL IMPRESSION OF CHANGE  
The PGIC will be assessed at the visits specified in the SoA (Section 1.3). The PGIC is a 
single-item, self-administered questionnaire, which asks the subject to rate the change in their 
symptom severity (“Very much better” to “Very much worse”). 
The PGIC will be completed by the subject on a worksheet prior to any safety and efficacy 
evaluations. The questionnaire is self-explanatory and handed to the subject who is asked to fill it 
in without the need for a detailed explanation. The PGIC (modified from Yalcin 2003) is 
presented in Appendix 5. 
 
HIDRADENITIS SUPPURATIVA PATIENT’S GLOBAL ASSESSMENT  
The HS-PtGA asks the subject to assess how HS has influenced their quality of life. Scores are 
on a 5-point scale from ‘not at all’ to ‘extremely’, with higher scores indicating more severe 
impact on quality of life (Kirby 2021). The HS-PtGA is shown in Appendix 6.  
 
DERMATOLOGY LIFE QUALITY INDEX QUESTIONNAIRE 
The DLQI questionnaire will be assessed at the visits specified in the SoA (Section 1.3). It is a 
simple 10-question validated questionnaire (Finlay 1994; Lewis-Jones 1995). The DLQI score 
ranges from 0 (no effect on the subject’s life) to 30 (extremely large effect on the subject’s life), 
with higher score indicating greater impairment of quality of life.  
The DLQI will be completed by the subject on a worksheet prior to any safety and efficacy 
evaluations. The questionnaire is self-explanatory and will be filled in by the subject without the 
need for a detailed explanation. The DLQI is presented in Appendix 7. 
 
 
 
 
 
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HIDRADENITIS SUPPURATIVA QUALTY OF LIFE  
The HiSQOL questionnaire is a 17-item questionnaire scored from 0 to 68 with domains for 
symptoms, activity-adaptation, and psychosocial impact with higher scores representing a more 
severe disease impact (Kirby 2020). Each domain may also be scored on the following 
subscores: symptoms (0-16), activity-adaptation (0-32) and psychosocial (0-20). The 
questionnaire is presented in Appendix 8.  
The HiSQOL will be completed by the subject on a worksheet prior to any safety and efficacy 
evaluations. The questionnaire is self-explanatory and will be filled in by the subject without the 
need for a detailed explanation. 
 
HIDRADENITIS SUPPURATIVA PHYSICIAN’S GLOBAL ASSESMENT  
The HS-PGA (refer to Appendix 9) documents the physician’s assessment of the subject’s overall 
HS activity at a given timepoint based on the presence and relative number of HS lesions, 
drainage and pain and/or tenderness across all HS involved areas. Using the descriptors provided 
for each distinct category, the subject’s HS is assessed as inactive (0), almost inactive (1), mild 
(2), moderate (3), or severe (4). A higher score indicates more severe disease. 
 
HURLEY STAGES OF HIDRADENITIS SUPPURATIVA 
The Hurley system describes 3 clinical stages of HS (Hurley 1989; Kimball 2014): 
 Stage 1 – abscess formation, single or multiple, without sinus tracts and cicatrization 
 Stage 2 – single or multiple, widely separated, recurrent abscesses with tract formation 
and cicatrization 
 Stage 3 – diffuse or near-diffuse involvement, or multiple interconnected tracts and 
abscesses across the entire area. 
The participant is assigned Hurley Stage corresponding to the Hurley Stage of his or her worst 
involved anatomic region. 
 
ABSCESS, INFLAMMATORY NODULE, AND DRAINING FISTULA 
COUNT 
Abscess (fluctuant, with or without drainage, tender or painful), inflammatory nodules (tender, 
erythematous, pyogenic granuloma lesion), draining fistulas, sinus tracts with communications to 
skin surface, draining purulent fluid, and other lesions (noninflammatory nodules, non-draining 
fistulas) will all be individually counted on the entire body at each visit. The AN count will be 
calculated based on the sum of the abscesses and inflammatory nodules. See the Study Manual 
for additional details. 
The location of existing lesions and draining fistulas and new occurrences should be documented 
in the eCRF. 
 
 
 
 
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“Lack of efficacy” or “failure of expected pharmacological action” per se will not be reported as 
an AE or SAE. 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 AE or SAE 
if they fulfill the definition of an AE or SAE. 
8.2.1.1.2 EVENTS NOT MEETING THE ADVERSE EVENT DEFINITION 
Events not meeting the AE definition include: 
 Any clinically significant abnormal laboratory findings or other abnormal safety 
assessments which are associated with the underlying disease, unless judged by the 
Investigator to be more severe than expected for the subject’s condition. 
 The disease/disorder being studied or expected progression, signs, or symptoms of the 
disease/disorder being studied, unless more severe than expected for the subject’s 
condition. 
 Medical or surgical procedure (eg, endoscopy, appendectomy): the condition that leads to 
the procedure is the AE. 
 Situations in which an untoward medical occurrence did not occur (social and/or 
convenience admission to a hospital). 
 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. 
8.2.1.2 
DEFINITION OF SERIOUS ADVERSE EVENTS  
An AE or suspected adverse reaction is considered "serious" if, in the view of either the 
Investigator or AnaptysBio, it results, at any dose, in any of the following outcomes:  
 Death 
 Life-threatening adverse event – The term ‘life-threatening’ in the definition of 
“serious” refers to an event in which the subject was at risk of death at the time of the 
event. It does not refer to an event, which hypothetically might have caused death, if it 
were more severe. 
 Inpatient hospitalization or prolongation of existing hospitalization – In general, 
hospitalization signifies that the subject has been admitted (usually involving at least an 
overnight stay) at the hospital or emergency ward for observation and/or treatment that 
would not have been appropriate in the physician’s office or outpatient setting. 
Complications that occur during hospitalization are AEs. If a complication prolongs 
hospitalization or fulfills any other serious criteria, the event is serious. When in doubt as 
to whether “hospitalization” occurred or was necessary, the AE should be considered 
serious. Hospitalization for elective treatment of a pre-existing condition that did not 
worsen from Baseline is not considered an AE. 
 Persistent or significant incapacity or substantial disruption of the ability to conduct 
normal life functions – The term disability means a substantial disruption of a person’s 
ability to conduct normal life functions. This definition is not intended to include 
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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. 
 Congenital anomaly/birth defect 
 Other important medical events – Events that may not result in death, be life-
threatening, or require hospitalization may be considered serious when, based upon 
appropriate medical judgment, they may jeopardize the subject and may require medical 
or surgical intervention to prevent one of the outcomes listed in this definition. Examples 
of such medical events include invasive or malignant cancers, allergic bronchospasm 
requiring intensive treatment in an emergency room or at home, blood dyscrasias or 
convulsions that do not result in inpatient hospitalization, or the development of drug 
dependency or drug abuse.  
8.2.1.3 
CLASSIFICATION OF AN ADVERSE EVENT 
8.2.1.3.1 SEVERITY OF EVENT 
The intensity of an AE is an estimate of the relative severity of the event. The Investigator will 
make an assessment of intensity for each AE and SAE reported during the study based on his or 
her clinical experience and familiarity with the literature. The following definitions are to be 
used to rate the severity of an AE: 
 Mild – Events require minimal or no treatment, are easily tolerated by the subject, 
causing minimal discomfort, and do not interfere with the subject’s daily activities.  
 Moderate – Events result in a low level of inconvenience or concern with the therapeutic 
measures. Moderate events may cause some interference with functioning and sufficient 
discomfort to the subject. 
 Severe – Events interrupt a subject’s usual daily activity and may require systemic drug 
therapy or other treatment. Severe events are usually potentially life-threatening or 
incapacitating. Of note, the term “severe” does not necessarily equate to “serious”. An AE 
that is assessed as severe should not be confused with a SAE. Severe is a category 
utilized for rating the intensity of an event, and both AEs and SAEs can be assessed as 
severe. An event is defined as ‘serious’ when it meets at least 1 of the predefined 
outcomes as described in the definition of an SAE, NOT when it is rated as severe. 
8.2.1.3.2 RELATIONSHIP TO STUDY TREATMENT 
All AEs must have their relationship to study treatment assessed by the Investigator who 
examines and evaluates the subject based on temporal relationship and his or her clinical 
judgment. 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 IB in his or her assessment. 
The degree of certainty about causality will be graded using the categories below. In a clinical 
study, the study treatment must always be suspect.  
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 Unrelated – Clinical event incontrovertibly not related to the study treatment.  
 Unlikely to be related – Clinical event with an incompatible time relationship to study 
treatment administration which makes a causal relationship improbable, and in which an 
underlying condition or other drugs or chemicals provides plausible explanations.  
 Possibly related – Clinical event with a reasonable time relationship to study treatment 
administration, and that is unlikely to be attributed to concurrent condition or other drugs 
or chemicals.  
 Related – Clinical event with plausible time relationship to study treatment 
administration and that cannot be explained by concurrent condition or other drugs or 
chemicals.  
For each AE/SAE, the Investigator must document in the medical notes that he or she has 
reviewed the AE/SAE and has provided an assessment of causality.  
There may be situations in which an SAE has occurred, and the Investigator has minimal 
information to include in the initial report to the pharmacovigilance unit. However, it is very 
important that the Investigator always make an assessment of causality for every event before the 
initial transmission of the SAE data to the pharmacovigilance unit within 24 hours of awareness 
of the event. 
The Investigator may change his or her opinion of causality in light of follow-up information and 
send a SAE follow-up report with the updated causality assessment. 
The causality assessment is one of the criteria used when determining regulatory reporting 
requirements. 
8.2.1.3.3 EXPECTEDNESS  
The pharmacovigilance unit will be responsible for determining whether an AE is expected or 
unexpected as interpreted through the IB. An AE will be considered unexpected if the nature, 
severity, or frequency of the event is not consistent with the risk information previously 
described for the study treatment. 
8.2.1.4 
TIME PERIOD AND FREQUENCY FOR EVENT ASSESSMENT AND 
FOLLOW-UP 
The occurrence of an AE or SAE may come to the attention of study personnel during study 
visits and interviews of a study subject presenting for medical care, or upon review by a study 
monitor. 
All AEs including local and systemic reactions will be captured on the appropriate eCRF. 
Information to be collected includes event description, date of onset, clinician’s assessment of 
severity, seriousness, relationship to study treatment (assessed only by those with the training 
and authority to make a diagnosis), action taken, and outcome of the event. All AEs occurring 
while on study must be documented appropriately regardless of relationship (see Section 
8.2.1.3.2). All AEs will be followed to adequate resolution or stabilization. 
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Study site personnel will note the occurrence and nature of each subject’s medical condition(s) 
present prior to the informed consent signature in the appropriate section of the source document 
and eCRF. During the study, study site personnel will note any change in the condition(s) and the 
occurrence and nature of any AE. Care will be taken not to introduce bias when detecting AEs 
and/or SAEs. Open-ended and nonleading verbal questioning of the subject is the preferred 
method to inquire about AE occurrences. 
Should a subject experience an AE at any time after the screening visit informed consent 
signature until the end of participation in the study, the event will be recorded as an AE in the 
source document and eCRF. Any SAE related to the study participation (eg, screening procedure) 
will be recorded in the source document and eCRF from the time consent is given to participate 
in the study until the end of participation in the study (EOS/ET visit).  
Investigators are not obligated to actively seek AEs or SAEs after conclusion of the study 
participation. However, if the Investigator learns of any SAE, including a death, at any time after 
a subject has been discharged from the study, and he or she considers the event to be reasonably 
related to the study treatment or study participation, the Investigator must promptly notify the 
pharmacovigilance unit.  
Any medical condition that is present at the time that the subject is screened will be considered 
as medical history and not reported as an AE. However, if the study subject’s condition 
deteriorates at any time during the study, it will be recorded as an AE.  
Changes in the severity of an AE/SAE will be documented to allow an assessment of the duration 
of the event at each level of severity to be performed. AEs characterized as intermittent require 
documentation of onset and duration of each episode. 
The Investigator is responsible for appropriate medical care of subjects during the study. After 
the initial AE/SAE report, the Investigator is required to proactively follow each subject at 
subsequent visits/contacts. The Investigator also remains responsible for following through with 
an appropriate health care option for all AEs that are ongoing at the end of the study. The subject 
should be followed until the event is resolved or stable. If an AE is ongoing at the end of study, 
the follow-up duration is left to the discretion of the Investigator. Follow-up frequency will be 
performed at the discretion of the Investigator.  
Whenever possible, clinically significant abnormal laboratory results are to be reported using the 
diagnostic that resulted in the clinically significant abnormal laboratory results and not the actual 
abnormal test. 
8.2.1.5 
ADVERSE EVENT REPORTING  
When an AE/SAE occurs, it is the responsibility of the Investigator to review all documentation 
(eg, hospital progress notes, laboratory reports, and diagnostics reports) related to the event. 
The Investigator will then record all relevant AE/SAE information (including event term, start 
and stop dates, severity, relationship to study treatment, outcome, if serious or non-serious) in the 
eCRF. Each event must be recorded separately. 
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It is not acceptable for the Investigator to send photocopies of the subject’s medical records to 
the pharmacovigilance unit in lieu of completion of the AE/SAE eCRF page. 
There may be instances when copies of medical records for certain cases are requested by the 
pharmacovigilance unit. In this case, all subject identifiers, with the exception of the subject 
number, will be redacted on the copies of the medical records before submission to the 
pharmacovigilance unit. 
The Investigator will attempt to establish a diagnosis of the event based on signs, symptoms, 
and/or other clinical information. Whenever possible, the diagnosis (not the individual 
signs/symptoms) will be documented as the AE/SAE. 
The Investigator is obligated to perform or arrange for the conduct of supplemental 
measurements and/or evaluations as medically indicated or as requested by the 
pharmacovigilance unit to elucidate the nature and/or causality of the AE or SAE as fully as 
possible. This may include additional laboratory tests or investigations, histopathological 
examinations, or consultation with other health care professionals. 
New or updated information will be recorded in the originally completed eCRF. 
8.2.1.6 
SERIOUS ADVERSE EVENT REPORTING  
Prompt notification by the Investigator to the pharmacovigilance unit of an SAE 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. All SAEs will be recorded and reported to 
the pharmacovigilance unit within 24 hours of awareness. The Investigator will submit any 
updated SAE data to the pharmacovigilance unit within 24 hours of receipt of the information as 
outlined in the Safety Reporting Instructions that will be provided to the study sites and in the 
study Safety Management Plan. 
The pharmacovigilance unit will inform the Medical Monitor, AnaptysBio, and Innovaderm 
within 1 business day of awareness of a new SAE. The pharmacovigilance unit will process and 
evaluate all SAEs as soon as the reports are received. For each SAE received, the 
pharmacovigilance unit, in consultation with AnaptysBio if needed, will make a determination as 
to whether the criteria for expedited reporting to relevant regulatory authorities have been met. 
AnaptysBio 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. 
or designee will comply with country specific regulatory requirements relating to safety 
reporting to the regulatory authority, IRB/EC, and Investigators. 
Investigator safety reports must be prepared for suspected unexpected SAEs according to local 
regulatory requirements and pharmacovigilance unit policy, and forwarded to Investigators as 
necessary. 
An Investigator who receives an Investigator safety report describing an SAE or other specific 
safety information (eg, summary or listing of SAEs) from the pharmacovigilance unit will review 
and then file it along with the IB and will notify the IRB/EC, if appropriate according to local 
requirements.  
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If a subject dies while participating in the study, the Investigator will provide the 
pharmacovigilance unit with a copy of any postmortem findings.  
8.2.1.6.1 REPORTING VIA AN ELECTRONIC DATA COLLECTION TOOL  
The primary mechanism for reporting an SAE to the pharmacovigilance unit will be the 
electronic data capture (EDC) clinical database. 
If the electronic system is unavailable, then the study site will use the back-up paper SAE Report 
Form. The study site will then enter the SAE data into the EDC system as soon as it becomes 
available. 
After the study is completed and the database is locked, the tooled system will be taken off-line 
to prevent the entry of new data or changes to existing data. 
If a study site receives a report of a new SAE from a subject or receives updated data on a 
previously reported SAE after the EDC system is locked, then the study site can report this 
information on a paper SAE form and email the form to the pharmacovigilance unit. 
Contacts for SAE reporting can be found in SAE form and Safety Reporting Instructions that 
will be provided to the study sites. 
8.2.1.6.2 REPORTING VIA PAPER CASE REPORT FORM  
In rare circumstances, and in the absence of EDC or email, notification by telephone is 
acceptable for notifying the pharmacovigilance unit of an SAE. Once the EDC is available, the 
SAE must be reported in the system within 24 hours of it becoming available. 
Initial notification via telephone does not replace the need for the Investigator to complete and 
sign the SAE CRF pages within the designated reporting time frames. 
Contacts for SAE reporting can be found in Safety Reporting Instructions that will be provided 
to the study sites. 
8.2.1.7 
REPORTING EVENTS TO SUBJECTS  
Not applicable. 
8.2.1.8 
REPORTING OF PREGNANCY  
If a female subject or a female partner of a male subject becomes pregnant during the study and 
up to 28 days after the end of the study, the subject should inform the study site as soon as 
possible. 
If a pregnancy is reported, the Investigator should inform the pharmacovigilance unit within 
24 hours of learning of the pregnancy and should follow the procedures outlined in Appendix 1. 
If a pregnancy occurs, it will be followed up to determine the outcome, but no longer than 6 to 
8 weeks after the estimated delivery date, where consent has been obtained to do so. 
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Abnormal pregnancy outcomes (eg, spontaneous abortion, fetal death, stillbirth, congenital 
anomalies, and ectopic pregnancy) are considered SAEs and must be reported within 24 hours of 
awareness as described in Section 8.2.1.6. 
8.2.1.9 
TREATMENT OF OVERDOSE  
For this study, any dose of imsidolimab or placebo administered in a volume exceeding the 
planned dosing detailed in Table 3 (Dose Strength[s]/Dosage Level[s]) will be considered an 
overdose. 
In the improbable event of a suspected overdose, the following procedures should be executed: 
 Administration is to be discontinued. 
 The subject is to be monitored clinically. 
 Supportive measures are to be undertaken as clinically indicated. 
 Electrocardiography and clinical laboratory evaluations (ie, blood glucose, hepatic 
enzymes, creatinine, blood urea nitrogen, creatine kinase (CK), and complete blood 
count) are to be performed and followed until all values return to Baseline levels and AEs 
subside, if applicable. 
No information on overdose, maximum tolerated dose, or dose-limiting toxicities for 
imsidolimab has been established at this time and since there are no known antidotes for 
imsidolimab, the treatment of overdose is at Investigator’s discretion. 
In the event of an overdose, the Investigator should: 
1. Contact the Medical Monitor immediately. 
1. Closely monitor the subject for any AE/SAE and laboratory abnormalities and follow-up 
until resolution. 
2. Obtain a serum sample for PK analysis soon after the dose for SC administration. 
3. Document the quantity of the excess dose as well as the duration of the overdose in the 
eCRF. 
Decisions regarding dose interruptions will be made by the Investigator in consultation with the 
Medical Monitor based on the clinical evaluation of the subject. 
 
HEIGHT AND WEIGHT 
Height (cm) and weight (kg) will be collected to calculate the body mass index (BMI). Height 
and weight will be measured at the time points specified in the SoA (Section 1.3). 
 
CHEST X-RAY 
Bidirectional posterior-anterior and lateral view chest X-ray will be performed at screening 
(Section 1.3). If a chest X-ray was performed within 6 months of screening and no clinically 
significant abnormality was observed, it can be skipped at screening. 
 
 
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PHYSICAL EXAMINATIONS 
Complete physical examinations will be performed at the time points indicated in the SoA 
(Section 1.3). 
A complete physical examination will include assessments of general appearance; skin; 
head/neck; pulmonary, cardiovascular, gastrointestinal, lymphatic, and musculoskeletal system; 
extremities; eyes; nose; throat; and neurologic status. The indication under study, hidradenitis 
suppurativa, should not be reported as part of the physical examination. 
A detailed examination of the skin should be performed at the time points indicated in the SoA 
for the efficacy assessments (eg, AN count). 
Investigators should pay special attention to clinical signs related to previous serious illnesses. 
 
VITAL SIGNS 
Body temperature (°C), pulse rate (bpm), blood pressure (mmHg), and respiratory rate 
(breath/min) will be assessed at the time points specified in SoA (Section 1.3). 
Blood pressure and pulse rate will be assessed in a seated position with a completely automated 
device. Manual techniques will be used only if an automated device is not available. 
Assessments should be preceded by at least 5 minutes of rest for the subject in a quiet setting 
without distractions (eg, television, cell phones). 
Vital signs including body temperature, respiratory rate, and pulse rate (after at least 5 minutes 
rest) should be measured once. Arterial blood pressure should be measured once, using a 
validated device, and recorded in the eCRF. 
 
ELECTROCARDIOGRAMS 
A single 12-lead ECG will be obtained at the time points specified in the SoA (see Section 1.3) 
using a validated ECG machine that automatically calculates the heart rate and measures RR, PR, 
QRS, QT, and QTcF intervals. 
Additional information will be provided in a separate manual. 
The ECG will be reviewed by the Investigator or an authorized representative who is 
experienced in the evaluation of ECGs and assessed for clinical significance. 
The ECG individual data (including clinical significance that will be reported as AE) will be 
entered into the electronic data capture (EDC). 
 
CLINICAL SAFETY LABORATORY ASSESSMENTS 
See Appendix 11 for the list of clinical laboratory tests to be performed and the SoA 
(Section 1.3) for the timing and frequency of the tests. 
 
 
 
 
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will be obtained from each subject for PK assessments during the study. Each serum sample will 
be divided into 2 aliquots (1 each for primary and a back-up). Samples collected for analyses of 
imsidolimab serum concentration also may be used to correlate exposure to safety or efficacy as 
well as supportive analysis for dose justification.  
The actual date and time (24-hour clock) of the blood sample collection will be recorded in the 
subject’s eCRF. The details of blood sample collection, sample tube labeling, sample preparation, 
storage, and shipping procedures will be described in a separate laboratory manual. 
The measurement of the concentrations of imsidolimab will be performed using a validated assay 
method under the supervision of AnaptysBio. The analytical methods used to measure 
concentrations of imsidolimab will be described in a separate bioanalytical report. 
Only samples within the stability window of the assay will be analyzed.   
While PK samples must be collected from subjects randomized to the placebo arm to maintain 
the blinding of treatment assignment, PK assay results for these subjects are not needed for the 
safe conduct or proper interpretation of this study. These samples may not be analyzed unless 
needed to investigate if a dosing error has occurred. Personnel at the bioanalytical laboratory 
performing PK assays will be unblinded, the clinical study team members, and study site staff 
(with the exception of the unblinded Pharmacist) will remain blinded to treatment for the 
duration of the study. Data may be de-identified for quality review. Additional details on de-
identification or unblinding of the PK data, if applicable, will be described in a separate plan. 
Drug concentration information that may unblind the study will not be reported to study sites or 
blinded personnel until the study has been unblinded.  
Table 5: Pharmacokinetic and Anti-drug Antibody Collection Schedule 
Study Visit 
PK Sample Time Point  
ADA Sample Time Point 
Day 1 
Predose  
Predose 
Day 29 
Predose 
Predose 
Day 57 
Predose 
Predose 
Day 85 
Predose 
Predose 
Day 113 
Predose 
Predose 
Day 141 
Predose 
Predose 
Day 169 
Predose 
- 
Day197 
Predose 
- 
Day 225 
Anytime 
Anytime 
Day 253 
Anytime 
- 
Day 281 
Anytime 
Anytime 
Abbreviations: ADA, anti-drug antibody; hr, hours; min, minutes; PK, pharmacokinetic 
 
IMMUNOGENICITY ASSESSMENTS 
Anti-drug antibodies to imsidolimab will be evaluated in serum samples collected from all 
subjects according to the SoA (Section 1.3) and Table 5. Additionally, serum samples also should 
also be collected at the final visit from subjects who discontinued study treatment or were 
 
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withdrawn from the study. These samples will be tested by AnaptysBio or its designee. Each 
serum sample will be divided into 2 aliquots (1 each for primary and a back-up). 
The detection and characterization of antibodies to imsidolimab will be performed using a 
validated assay method by or under the supervision of AnaptysBio.  
Serum samples will be tested in a multi-tiered approach. A validated screening assay for 
antibodies binding to imsidolimab initially will be used to assess serum samples. Samples that 
are determined putative positive in the screening assay then will be subjected to a confirmatory 
assay to demonstrate that antibodies are specific to imsidolimab. Samples that are identified as 
positive in the confirmatory assay will be further characterized in a validated titer assay and the 
titer of confirmed positive samples will be reported. Other analyses may be performed to verify 
the stability of antibodies to study treatment and/or to further characterize the immunogenicity of 
study treatment.  
Samples that are confirmed positive for antibodies binding to imsidolimab may be further 
characterized for their ability to neutralize the activity of the study treatment using a validated 
neutralizing antibody assay method and the presence and/or titer of ADA may be correlated to 
safety and PK data.  
 
BIOMARKER ANALYSIS 
The actual date and time of the biomarker sample collection will be recorded in the subject’s 
eCRF. The details of sample collection, sample tube labeling, sample preparation, storage, and 
shipping procedures will be described in a separate Laboratory Manual. 
The measurement of biomarkers may be performed by an additional third party (eg, a university 
Investigator) designated by AnaptysBio. 
8.3.5.1 
TAPE STRIPPING 
Tape strip samples will be collected from non-lesional and lesional skin according to the SoA 
(Section 1.3) to measure cutaneous biomarkers including but not limited to IL-36R, Th-17 
cytokines such as IL-17A, and markers of neutrophils and dendritic cell infiltration.  
8.3.5.2 
DRAINAGE FLUID COLLECTION 
Optional noninvasive collection of drainage fluid to assess biomarkers may be conducted at any 
visit after screening. Drainage fluid should be collected where present from areas that are 
draining the most.  
 
 
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of subjects in the relevant analysis set with assessments available [where appropriate]) in each 
category will be the default summary presentation. 
Unless otherwise specified, “Baseline” is defined as the last observed value of the parameter of 
interest prior to the first intake of study treatment (this includes unscheduled visits). For 
numerical variables, change from Baseline will be calculated as the difference between the value 
of interest and the corresponding Baseline value. In the analysis of extension study subjects 
using the Extension Analysis Set, for those subjects who received placebo initially, their baseline 
will be re-calculated based on the latest data prior to receiving imsidolimab.   
Unless otherwise specified, all formal statistical tests will be 2-sided at the 10% significance 
level. Point estimates of treatment differences will be accompanied with 2-sided 90% confidence 
intervals (CIs), where applicable. 
In the case of normality assumption violations, appropriate nonparametric methods may be used 
for analysis. 
All data will be presented in by-subject listings. 
 
SUBJECT DISPOSITION 
A tabular presentation of the subject disposition will be provided. It will include the number of 
subjects screened, randomized, treated, completed as well as the number of dropouts with 
reasons for discontinuation, and major protocol deviations or violations. 
A listing will be presented to describe dates of screening, assigned treatment, screen failed with 
reason, completion or early withdrawal, and the reason for early discontinuation, if applicable, 
for each subject. A list of protocol deviations/violations will be identified and discussed with the 
Investigator/AnaptysBio in dry run to categorize as major or minor with decisions of exclusion 
from analysis sets prior to unblinding. 
During the COVID-19 pandemic, protocol deviations related to COVID-19 will be documented 
and information on how they will be handled in the analyses will be detailed in the SAP. 
 
BASELINE DESCRIPTIVE STATISTICS 
Subject characteristics obtained at Baseline will be summarized for all subjects taking 
imsidolimab or placebo. 
Summaries will include descriptive statistics for continuous variables (sample size [n], mean, 
SD, median, minimum, and maximum) and for categorical variables (n, frequency, and 
percentage). 
Medical history will be coded using the Medical Dictionary for Regulatory Activities (MedDRA) 
latest version and listed for all subjects. 
 
 
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CONCOMITANT MEDICATION 
All medications will be coded using the World Health Organization Drug Dictionary and 
Anatomical Therapeutic Chemical system. Each medication will be classified as prior medication 
if it is stopped prior to the first dose of study treatment, or as concomitant medication if it is 
ongoing at the time of the first dose or is started after the first dose of study treatment. Prior, 
concomitant, and rescue medications will be summarized descriptively with a by-subject listing. 
To handle the issue of rescue medication use, the efficacy data on and after the use rescue 
medication will be set to missing in the efficacy analysis. 
 
ANALYSIS OF THE PRIMARY EFFICACY ENDPOINT 
The primary efficacy endpoint is the change from Baseline in AN count at Week 16.  
The primary estimand, comprising four components, is defined as follows: 
a) The target population consists of subjects with hidradenitis suppurativa who are eligible 
to be included in the clinical trial based on the inclusion/exclusion criteria in the protocol. 
The ITT analysis set will include all randomized subjects. For the analysis, treatment will 
be assigned based upon the treatment arm to which subjects are randomized regardless of 
which treatment they receive.  
b) The primary variable is the change from baseline in AN count of an individual subject at 
Week 16.   
c) To handle intercurrent events such as use of rescue medications, the hypothetical strategy 
for estimand will be used. Data collected following receipt of rescue medication (if any) 
will be considered missing in the analysis.  
d) The population-level summary measures will be the population mean differences in the 
primary variable between each dose of imsidolimab and placebo at Week 16. 
A general linear mixed effects model for repeated measures (MMRM) analysis will be used to 
estimate the least squares means (LSM) and associated standard errors for the change from 
Baseline in AN count to Week 16. The model will include change from Baseline in AN count at 
Week 16 as the dependent variable, fixed effects for treatment arm, categorical time point, and 
the treatment by time point interaction, and the Baseline AN count and stratification factor (ie, 
Hurley Stage at baseline (Stage II or III)) as covariates. An unstructured covariance structure will 
be used. The difference between LSMs (imsidolimab – placebo) at Week 16 will be presented 
along with the associated 90% CI and p-value. The ITT analysis set will be used for the primary 
efficacy analysis. 
 
ANALYSIS OF THE SECONDARY EFFICACY ENDPOINTS 
The ITT analysis set will be used for analysis of secondary efficacy endpoints. Following are the 
secondary efficacy endpoints: 
 Percent change from Baseline in AN count at Week 16 
 Proportion of subjects achieving HiSCR50 at Week 16 
 
 
 
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 Change from Baseline in HS Pain NRS at Week 16  
 Percent change from Baseline in HS Pain NRS at Week 16 
9.4.6.1 
CATEGORICAL ENDPOINTS 
Frequency and percentages for each response Yes/No for categorical endpoints will be presented 
separately by visit for each treatment arm. Subjects with missing scores at a given visit will be 
considered to have not met the criteria of interest (ie, nonresponse). Estimates of the difference 
between treatments (imsidolimab – placebo) will be presented along with exact 90% CIs. 
Treatment arms will be compared using Cochran–Mantel–Haenszel chi-squared test, adjusted for 
stratification factor (Hurley Stage at baseline (Stage II or III)). 
9.4.6.2 
CONTINUOUS ENDPOINTS 
Summary statistics will be provided by visit and treatment arm. A by-subject listing will be 
presented for each assessment, by visit. Mixed model for repeated measures (MMRM) method 
for longitudinal continuous data will be used for testing, with treatment group as main effect, 
with visit and interaction of treatment by visit as factors, and with baseline values and 
stratification factor (Hurley Stage at baseline [Stage II or III]) as covariates.  
 
ANALYSIS OF THE EXPLORATORY ENDPOINTS  
Following are the exploratory endpoints: 
 Change from Baseline in AN count at visits other than Week 16 
 Percent change from Baseline in AN count at visits other than Week 16 
 Proportion of subjects achieving AN50 and AN75 responses  
 Percentage of subjects experiencing flare, defined as a ≥25% increase in AN count with 
an absolute increase in AN count of ≥2 relative to Baseline at each visit 
 Change from Baseline in abscess count at each visit 
 Change from Baseline in inflammatory nodule count at each visit 
 Change from Baseline in draining fistula count at each visit 
 Proportion of subjects achieving HiSCR50 at visits other than Week 16 
 Proportion of subjects achieving HiSCR75 at each visit 
 Proportion of subjects achieving 0 (inactive) or 1 (almost inactive) on HS-PGA at each 
visit 
 Proportion of subjects with ≥ 2-point reduction from Baseline on HS-PGA at each visit 
 Change from Baseline in HS-PGA 
 Change from Baseline in calculated composite of abscesses, draining fistulas, and 
inflammatory and non-inflammatory nodules 
 Change from Baseline in HS Pain NRS at visits other than Week 16 
 Percent change from Baseline in HS Pain NRS at visits other than Week 16 
 
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 Proportion of subjects achieving a ≥ 3-point reduction on the HS Pain NRS for subjects 
with Baseline HS Pain NRS of at least 3 
 Proportion of subjects requiring rescue medication or treatment at each visit 
 Change from Baseline in DLQI score at each visit 
 Change from Baseline in IHS4 at each visit 
 Change from Baseline in HiSQoL at each visit 
 Change from Baseline in HS-PtGA at each visit 
 Proportion of subjects in each response category for the HS-PtGA at each visit 
 Proportion of subjects in each response category for the PGIC at each visit 
 Proportion of subjects achieving improvement (“Much better” or “Very much better”) 
according to the PGIC at each visit 
 Proportion of subjects achieving improvement (“A little better”, “Much better” or “Very 
much better”) according to the PGIC at each visit 
 Proportion of subjects in each response category for the PGIB at each visit 
 Change from Baseline in PGIB at each visit 
 Proportion of subjects achieving “A little bothered” or “Not at all bothered” for the PGIB 
at each visit 
 Proportion of subjects in each response category for the PGIS at each visit 
 Proportion of subjects achieving “Mild” or “No activity” according to the PGIS at each 
visit 
 Change from Baseline in PGIS at each visit 
 Proportion of subjects in each category of Hurley Stage at each visit 
 Change from Baseline in Hurley Stage at Weeks 16, 32, and 40  
 Proportion of subjects achieving at least a 1-stage improvement in Hurley stage 
 Skin tape strip and drainage fluid biomarkers analysis including, but not limited to, IL-36 
and Th-17 
 Presence of ADAs to imsidolimab 
 Serum concentration following imsidolimab administration and other parameters as 
appropriate will be determined to describe the PK profile of imsidolimab 
Methods for analyzing the above categorical and continuous efficacy endpoints will mirror the 
methods described in Section 9.4.6.1 and 9.4.6.2, respectively.  ITT analysis set will be used for 
analysis of exploratory efficacy endpoints.   
As further additional exploratory analyses, the primary efficacy endpoint, all secondary efficacy 
endpoints, and some of the exploratory endpoints will be summarized using the Extension 
analysis population. 
 
SAFETY ANALYSES 
Following are the primary safety and tolerability endpoints: 
 
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 Assessment of AEs, SAEs, and AEs leading to treatment discontinuation and study 
withdrawal. 
 Vital signs. 
 12-Lead ECG. 
 Clinical safety laboratory tests (hematology, biochemistry, and urinalysis). 
All safety analyses will be performed on the Safety Analysis Set. In addition, the safety data for 
the subjects who entered the extension period will also be analyzed by the Extension Analysis 
Set. 
9.4.8.1 
ADVERSE EVENTS AND SERIOUS ADVERSE EVENTS 
A TEAE is defined as: 
 A new event that occurs during or after first dose of study treatment or, 
 Any event present at Baseline that worsens in either intensity or frequency after first dose 
of study treatment. 
Adverse events will be coded using the MedDRA and only TEAEs will be summarized. Number 
of events and percentage will be tabulated by preferred term (PT) and primary system organ class 
(SOC). Multiple occurrences of an AE for a subject will only be counted once per primary SOC 
and PT. Percentages will be determined relative to the subjects in the Safety Analysis Set for the 
given treatment arm. 
If the intensity or seriousness of the AE changes, the overall intensity or seriousness will be the 
maximum intensity or seriousness of the multiple occurrences. The TEAEs, SAEs, TEAEs 
leading to treatment discontinuation, and TEAEs leading to withdrawal of subject will be 
tabulated for each treatment arm. 
All AE data will be listed for each subject. 
Summaries over SOC and PT of TEAEs, TEAEs leading to death, SAEs, and TEAEs that led to 
discontinuation from the study or study treatment will be presented by treatment. Summaries will 
also be presented by relatedness to the study treatment and the severity of the TEAE. 
9.4.8.2 
12-LEAD ELECTROCARDIOGRAM, VITAL SIGNS, AND CLINICAL 
SAFETY LABORATORY TESTS 
Summaries and listings of data for vital signs and safety laboratory tests result (hematology, 
biochemistry, and urinalysis) will be presented. Appropriate descriptive statistics will be 
summarized for the observed value at each scheduled assessment and for the corresponding 
change from Baseline. 
For hematology and biochemistry tests, listings of subject data will also flag up any abnormal or 
out-of-range values. Clinically significant changes in the laboratory test parameters will be 
summarized and listed. Hematology and biochemistry data will be reported in System 
International units. 
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Descriptive statistics will be used to present the safety outcomes including, weight, BMI, 
12-Lead ECG, vital signs, and clinical laboratory test results. 
Change from Baseline will also be summarized for vital signs, and clinical laboratory tests 
results. 
All ECG data results (normal/abnormal) will be summarized using frequency and percentage, 
and parameter values will be summarized descriptively. Clinically significant abnormalities will 
be presented in by-subject listings. 
 
PHARMACOKINETIC ANALYSES 
Limited imsidolimab PK analysis will be evaluated by assessment of drug concentrations in 
serum. These drug concentrations will be listed and summarized for each sampling time point 
using appropriate descriptive statistics. Due to limited PK sampling, noncompartmental analysis 
(NCA) will not be conducted in this study. 
9.4.9.1 
DERIVATION OF PHARMACOKINETIC PARAMETERS 
Due to limited PK sampling, NCA will not be conducted in this study. Thus, PK parameters will 
not be derived. 
9.4.9.2 
PHARMACOKINETIC CONCENTRATION DATA ANALYSIS 
A subject listing of all concentration-time data following SC injections will be presented by 
subject and scheduled sample collection time. 
Concentration data of imsidolimab will be summarized by day and nominal time point using the 
number of observations, arithmetic mean, SD, CV, minimum, median, maximum, and geometric 
mean. 
Graphs for mean concentration-time data following SC administration will be presented. 
Individual subject concentration-time plots will also be presented. 
Mean trough concentrations-time data will be graphically displayed for samples collected at the 
visits specified in the SoA (Section 1.3) to visually assess time to attainment of steady state. 
Time to steady state may also be explored by using inferential statistics, if deemed appropriate. 
Other presentations of data may be added at the discretion of the PK scientist, as appropriate, and 
will be described in detail in a separate analysis plan. 
9.4.9.3 
PHARMACOKINETIC PARAMETER DATA ANALYSIS 
No analysis will be performed on PK parameters. 
9.4.9.4 
POPULATION PHARMACOKINETICS ANALYSIS 
Pharmacokinetic data from the study may also be used for population PK and/or exposure-
response analyses. The data may be combined with PK data from other ANB019 studies, if 
 
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needed, to conduct the population PK analysis. If done, a separate analysis plan will be prepared, 
and results will be reported separately from the Clinical Study Report. 
9.4.9.5 
IMMUNOGENICITY ANALYSES 
Observed values for ADA levels/status will be listed by-subject and summarized with descriptive 
statistics based on the Safety Analysis Set. If data permits, potential correlation may be analyzed 
between ADA levels, serum concentration, and safety and efficacy endpoints. 
 In addition, ADA incidences (overall, treatment-emergent, and treatment-boosted) will be listed 
and summarized. 
 
BIOMARKER ANALYSES 
Tape strip biomarkers (including but not limited to IL-36R and Th-17 cytokine) analysis will be 
performed by a third party designated by AnaptysBio. A separate analysis plan will be created for 
the biomarker analyses. 
 
PLANNED INTERIM ANALYSIS  
Interim analyses (IA) may be performed for assessment of all primary and secondary efficacy 
endpoints, and evaluation of all safety data available.  
The rationale for these analyses is to assist in making decisions for potential future development 
of this treatment. No adjustments to the current protocol are planned as a result of the interim 
analyses; therefore, overall alpha in the analyses of the primary analysis is expected to be 
maintained at 0.10, two-sided. 
 
 
 
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The medical record must include a statement that written informed consent was obtained before 
the subject was entered in the study and the date the written consent was obtained. The 
authorized person obtaining the informed consent must also sign the ICF. 
Subjects must be re-consented to the most current version of the ICF(s) during their participation 
in the study. Subjects who are rescreened are required to sign a new ICF. 
 
STUDY DISCONTINUATION AND CLOSURE 
This study may be temporarily suspended or prematurely terminated if there is sufficient 
reasonable cause. Written notification, documenting the reason for study suspension or 
termination, will be provided by the suspending or terminating party to study subjects, 
Investigator, the IND Sponsor, and regulatory authorities, as applicable. If the study is 
prematurely terminated or suspended, the Investigator will promptly inform study subjects and 
the IRB/EC and will provide the reason(s) for the termination or suspension. Study subjects will 
be contacted, as applicable, and be informed of changes to study visit schedule.  
Circumstances that may warrant termination or suspension include, but are not limited to: 
 Determination of unexpected, significant, or unacceptable risk to subjects 
 Insufficient compliance to protocol requirements 
 Data that are not sufficiently complete and/or evaluable 
 Scientific or corporate reasons 
Study may resume once concerns about safety, protocol compliance, and data quality are 
addressed, and satisfy the AnaptysBio, IRB/EC and/or regulatory authorities. 
 
CONFIDENTIALITY AND PRIVACY  
Subject confidentiality and privacy are strictly held in trust by the participating Investigators, 
their staff, and AnaptysBio and their interventions. This confidentiality is extended to cover 
testing of biological samples and genetic tests in addition to the clinical information relating to 
subjects. Therefore, the study protocol, documentation, data, and all other information generated 
will be held in strict confidence. No information concerning the study or the data will be released 
to any unauthorized third party without prior written approval of AnaptysBio.  
All research activities will be conducted in a setting as private as possible. The Investigator must 
assure that the subjects’ anonymity will be maintained and that subjects’ identities are protected 
from unauthorized parties. On CRFs or other documents submitted to AnaptysBio, subjects 
should not be identified by their names, but by an identification code. The Investigator should 
keep a subject log relating codes with the names of subjects. The Investigator should maintain in 
strict confidence documents not for submission to AnaptysBio (eg, subjects’ written consent 
forms). 
The study monitor, other authorized representatives of AnaptysBio, and representatives of the 
IRB/EC, regulatory agencies, or pharmaceutical company supplying study treatment may inspect 
all documents and records required to be maintained by the Investigator, including but not 
 
 
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limited to, medical records (office, clinic, or hospital) and pharmacy records for the subjects in 
this study. The clinical study site will permit access to such records. 
The study subject’s contact information will be securely stored at each clinical study site for 
internal use during the study. At the end of the study, all records will continue to be kept in a 
secure location for as long a period as dictated by the applicable legal or regulatory requirements, 
the reviewing IRB/EC, Institutional policies, or AnaptysBio requirements. 
Study subject research data, which are for purposes of statistical analysis and scientific reporting, 
will be transmitted to and stored at the data management company responsible for data 
management, analysis, and reporting. This will not include the subject’s contact or identifying 
information. Rather, individual subjects and their research data will be identified by a unique 
study identification number. The study data entry and study management systems used by 
clinical study sites and by data management research staff will be secured and password 
protected. At the end of the study, all study databases will be de-identified and archived by 
AnaptysBio.  
All information generated in this study must be considered highly confidential and must not be 
disclosed to any persons not directly concerned with the study without written prior permission 
from AnaptysBio. Authorized regulatory officials and AnaptysBio personnel (or their 
representatives) will be allowed full access to inspect and copy the records. All study 
investigational product, subject bodily fluids, and/or other materials collected shall be used 
solely in accordance with this protocol, unless otherwise agreed to in writing by AnaptysBio. 
Subjects will only be identified by unique subject numbers on eCRFs. Every subject will be 
given a copy of each version of the ICF that he or she signs before and during the study. Each 
ICF may also include authorization allowing the institution, Investigator, and AnaptysBio to use 
and disclose personal health information in compliance with the Health Information Portability 
and Accountability Act (HIPAA). 
 
FUTURE USE OF STORED SPECIMENS AND DATA  
With the subject’s approval and approval by IRB/EC, de-identified biological samples will be 
stored at a certified, licensed central laboratory. During the conduct of the study, a subject may 
choose to withdraw consent to have biological specimens stored for future research. Once 
samples have been analyzed specimens will be destroyed. If no analyses have been completed 
within 5 years following EOS, samples will be destroyed.  
Any remaining serum/plasma from samples collected for PK/PD immunogenicity endpoints may 
be retained for assay method development, troubleshooting, or validation. These samples may 
also be used for research purposes, but will not be used for any type of genetic analyses.  
 
MEDICAL MONITOR 
Medical monitoring will be conducted to ensure the early recognition, identification and 
reporting of issues impacting on subjects’ health and well-being throughout the trial. Details of 
medical monitoring with contact information of the Medical Monitors will be documented in a 
Medical Monitoring Plan. 
 
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SAFETY OVERSIGHT 
No Data and Safety Monitoring Board is required as part of this study. 
 
CLINICAL MONITORING 
All aspects of the study will be monitored by AnaptysBio or authorized representatives of 
AnaptysBio according to GCP and Standard Operating Procedures (SOPs) for compliance with 
applicable government regulations, (ie, Informed Consent Regulations [US 21CFR, Part 50] and 
Institutional Review Board regulations [US 21CFR, Part 56.103]).  
Access to all records, both during the study and after study completion, should be made available 
to AnaptysBio at any time for review and audit to ensure the integrity of the data. The 
Investigator must notify AnaptysBio immediately if the responsible IRB/EC has been 
disqualified or if proceedings leading to disqualification have begun.  
The Investigator must conduct the protocol in accordance with applicable GCP regulations and 
guidelines; applicable informed consent regulations (US 21CFR, Part 50); and in compliance 
with the Declaration of Helsinki. Every attempt must be made to follow the protocol and to 
obtain and record all data requested for each subject at the specified times. If data are not 
recorded per protocol, the reasons must be clearly documented on the eCRF/records.  
Before study initiation, at a study site initiation visit or at a meeting with the Investigator(s), a 
representative from AnaptysBio will review the protocol and study eCRFs with the 
Investigator(s) and their staff. During the study, the study monitor will visit the study site 
regularly to check the completeness of subject records, the accuracy of entries on the eCRFs, the 
adherence to the protocol and to GCP, the progress of enrollment, and to ensure that consent is 
being sought and obtained in compliance with applicable regulations, and that the study drug is 
being stored, dispensed and accounted for according to specifications.  
The Investigator and key study personnel must be available to assist the monitor during these 
visits. The Investigator must give the monitor access to relevant hospital or clinical records, to 
confirm their consistency with the eCRF entries. No information in these records about the 
identity of the subjects will leave the study site.  
Monitoring standards require full verification for the presence of informed consent, adherence to 
the inclusion/exclusion criteria, documentation of SAEs, and the recording of primary efficacy 
and safety variables. Additional checks of the consistency of the source data with the eCRFs will 
be performed according to the study-specific Monitoring Plan.  
The Investigator must promptly complete the eCRFs after the subject’s visit. The monitor is 
responsible for reviewing them and clarifying and resolving any data queries. A copy of the 
eCRFs will be retained by the Investigator who must ensure that it is stored in a secure place 
with other study documents, such as the protocol, the IB, and any protocol amendments.  
The Investigator must provide AnaptysBio and the responsible IRB/EC with a study summary 
shortly after study completion, or as designated by AnaptysBio. 
 
 
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QUALITY ASSURANCE AND QUALITY CONTROL 
Each clinical study site will perform internal quality management of study conduct, data and 
biological specimen collection, documentation, and completion.   
Quality control (QC) procedures will be implemented beginning with the data entry system, and 
data QC checks, which will be run on the database, will be generated. Any missing data or data 
anomalies will be communicated to the study site(s) for clarification/resolution. 
Following written SOPs, the monitors will verify that the clinical trial is conducted and data are 
generated and biological specimens are collected, documented (recorded), and reported in 
compliance with the protocol, ICH GCP, and applicable regulatory requirements (eg, GLP, Good 
Manufacturing Practices).  
The investigational site will provide direct access to all trial related sites, source data/documents, 
and reports for the purpose of monitoring and auditing by AnaptysBio, and inspection by 
IRB/EC and local and regulatory authorities. 
 
DATA HANDLING AND RECORD KEEPING  
10.1.9.1 DATA COLLECTION AND MANAGEMENT RESPONSIBILITIES  
All protocol-specified data will be recorded in site source documents. Study data will be entered 
within the clinical database eCRFs from the original source documents. Upon each subject’s 
completion of the study, the Investigator is required to sign and affirm the data entered in the 
subject CRF along with a statement attesting that all pages of the subject’s case report have been 
reviewed. All Investigator data attestation signatures will be made through the 21 CFR Part 11 
compliant EDC system. Signature stamps and “per signatures” are not acceptable. 
It is AnaptysBio’s policy that study data be verifiable with the source data which necessitates 
access to all original recordings, laboratory reports, and other records for each subject. The 
Investigator must therefore agree to allow access to subjects’ records, and source data must be 
made available for all study data. Subjects (or their legal representatives) must also allow access 
to their medical records. Subjects will be informed of the importance of increased record access 
and permission granted by signature on the informed consent document prior to screening.  
Checks will be performed to ensure quality, consistency, and completeness of the data. Instances 
of missing or uninterpretable data will be resolved with the Investigator or study coordinator. 
Data queries, documented within the clinical database, will be accessible to the research facility 
through the EDC system. Study site personnel will be responsible for providing resolutions to the 
data queries and for correcting the eCRFs, as appropriate. 
The Investigator must keep written or electronic source documents for every subject participating 
in the clinical study. For the appropriate document retention period. The subject file that 
identifies the study in which the subject is participating must include the subject’s available 
demographic and medical information including:  
 
 
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 Name 
 Contact information 
 Year of birth 
 Sex 
 Fitzpatrick skin type 
 Medical historySmoking history 
 Concomitant therapies/medication 
 Study visit dates 
 Performed examinations, evaluations, and clinical findings 
 Investigational product administration 
 AEs, SAEs, or pregnancy (as applicable)  
Additionally, any other documents with source data, especially original printouts of data that 
were generated by technical equipment must be included in the subject’s source document (eg, 
laboratory value listings). All these documents must have at least the subject’s study number, and 
the date of the evaluation.  
The data recorded during the course of the study will be documented in the eCRF and/or the 
study-specific forms. Before or at study termination, all data must be forwarded to AnaptysBio. 
The data will then be recorded, evaluated, and stored in anonymous or coded form in accordance 
with data-protection regulations.  
Subjects will authorize the use of their protected health information during the informed consent 
process in accordance with the applicable privacy requirements. Subjects who deny permission 
to use and disclose protected health information will not be eligible to participate in the study.  
The Investigator will ensure that the study documents forwarded to AnaptysBio, and any other 
documents, contain no mention of subject names. Any amendments and corrections necessary 
will be undertaken in both the source documents and eCRFs (as appropriate), and countersigned 
by the Investigator, or documented designee, stating the date of the amendment/correction. 
Errors must remain legible and may not be deleted with correction aids. The Investigator must 
state his/her reason for the correction of any data. In the case of missing data/remarks, the entry 
spaces provided in the eCRF should be cancelled out so as to avoid unnecessary follow-up 
inquiries.  
Electronic CRFs will be kept by AnaptysBio or an authorized designee in a secured area. Clinical 
data will be recorded in a computer format for subsequent statistical analyses. Data files will be 
stored on electronic media with a final master data file kept by AnaptysBio after descriptive and 
statistical analyses and reports have been generated and are complete.  
It is the responsibility of the Investigator to ensure that the study site file is maintained in 
accordance with the ICH Guidance for Industry E6(R2) GCP: Consolidated Guidance, Section 8 
– Essential Documents for the Conduct of a Clinical Trial. 
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10.1.9.2 STUDY RECORDS RETENTION  
Study documents should be retained for a minimum of 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 the study treatment. These documents should be 
retained for a longer period, however, if required by local regulations or as specified in the study 
agreement, whichever retention period is longer.  
If the Investigator withdraws from the study (eg, relocation, retirement) all study-related records 
should be transferred to a mutually agreed upon designee. Notice of such transfer will be 
provided to AnaptysBio in writing. No records will be destroyed without the written consent of 
AnaptysBio, if applicable. It is the responsibility of AnaptysBio to inform the Investigator when 
these documents no longer need to be retained.  
 
PROTOCOL DEVIATIONS  
A protocol deviation is any noncompliance with the clinical trial protocol or ICH GCP 
requirements. The noncompliance may be either on the part of the subject, the Investigator, or the 
study site staff. As a result of deviations, corrective actions are to be developed by the study site 
and implemented promptly. Protocol deviations related to COVID-19 pandemic will be identified 
and documented accordingly. 
These practices are consistent with ICH GCP:  
 4.5 Compliance with Protocol, Sections 4.5.1, 4.5.2, and 4.5.3  
 5.1 Quality Assurance and Quality Control, Section 5.1.1  
 5.20 Noncompliance, Sections 5.20.1, and 5.20.2.  
It is the responsibility of the Investigator to use continuous vigilance to identify and report 
deviations as soon as possible. All deviations must be addressed in study source documents, and 
applicable deviations must be sent to the reviewing IRB/EC per their policies. The Investigator is 
responsible for knowing and adhering to the reviewing IRB/EC requirements. Further details 
about the handling of protocol deviations will be included in the Protocol Deviation Management 
Plan, Data Management Plan, Medical Monitoring Plan, blind data review documentation, and 
SAP.  
This study will be conducted as described in this protocol, except for an emergency situation in 
which the protection, safety, and well-being of the subject requires immediate intervention, based 
on the judgment of the Investigator (or a designee, appropriately trained professional designated 
by the Investigator). In the event of a significant deviation from the protocol due to an 
emergency, accident, or mistake, the Investigator or designee must contact the Medical Monitor 
and AnaptysBio at the earliest possible time by telephone. This will allow an early joint decision 
regarding the subject’s continuation in the study. This decision will be documented by the 
Investigator and the Medical Monitor. Please refer to Section 4.5 for allowable, as necessary, 
modifications to the protocol due to COVID-19 restrictions. 
 
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93 
The monitor must ensure that a prompt action is taken to secure compliance. If a noncompliance 
that significantly affects or has the potential to significantly affect human subject protection or 
reliability of trial results is discovered, the CRO and AnaptysBio should perform a root cause 
analysis and implement appropriate corrective and preventive actions. 
 
PUBLICATION AND DATA SHARING POLICY 
This study will be conducted in accordance with the following publication and data sharing 
policies and regulations: It is understood by the Investigator that the information generated in 
this study will be used by AnaptysBio in connection with the development of the product. To 
allow for the use of information derived from the study, it is understood that the Investigator is 
obliged to provide AnaptysBio with complete test results, all study data, and access to all study 
records.  
Any results of medical investigations with AnaptysBio’s products and/or 
publication/lecture/manuscripts based thereon, shall be exchanged and discussed by the 
Investigator and AnaptysBio representative(s), 30 days before submission for publication or 
presentation. Due regard shall be given to AnaptysBio’s legitimate interests for example, 
manuscript authorship, obtaining optimal patent protection, coordinating and maintaining the 
proprietary nature of submissions to health authorities, coordinating with other ongoing studies 
in the same field, and protecting confidential data and information. AnaptysBio, Inc. shall be 
furnished with a copy of any proposed publication. Comments shall be rendered without undue 
delay.  
In cases of publications or presentations of material arising from multicenter clinical 
investigations, AnaptysBio is to serve as coordinator and referee. Individual Investigators who 
are part of a multicenter investigation may not publish or present data that are considered 
common to a multicenter investigation without the consent of the other participating 
Investigators and the prior review of AnaptysBio.  
Results from investigations shall not be made available to any third party by the investigating 
team outside the publication procedure as outlined previously. AnaptysBio, Inc. will not quote 
from publications by Investigators in its scientific information and/or promotional material 
without full acknowledgment of the source (ie, author and reference). 
 
CONFLICT OF INTEREST POLICY 
The independence of this study from any actual or perceived influence is critical. Therefore, any 
actual conflict of interest of persons who have a role in the design, conduct, analysis, publication, 
financial interest, or any aspect of this trial will be disclosed and managed. Furthermore, persons 
who have a perceived conflict of interest will be required to have such conflicts managed in a 
way that is appropriate to their participation in the design and conduct of this study. AnaptysBio 
has established policies and procedures for all study group members to disclose all conflicts of 
interest and will establish a mechanism for the management of all reported dualities of interest. 
 
 
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Efficacy and Safety of Imsidolimab in Subjects with Hidradenitis Suppurativa 
 
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96 
Micheletti RG. Natural history, presentation, and diagnosis of hidradenitis suppurativa. Semin Cutan Med 
Surg. 2014 Jun;33(3 Suppl):S51-3.  
Sartorius K, Emtestam L, Jemec GB, et al. Objective scoring of hidradenitis suppurativa reflecting the 
role of tobacco smoking and obesity. Br J Dermatol 2009; 161: 831–839. 
Thomi R, Kakeda M, Yawalkar N, et al. Increased expression of the interleukin-36 cytokines in lesions of 
hidradenitis suppurativa. J Eur Acad Dermatol Venereol. 2017 Dec;31(12):2091-2096.  
Von Der Werth J, Williams H. The natural history of hidradenitis suppurativa. Journal of the European 
Academy of Dermatology and Venereology 2000; 14: 389-392.   
Wallace HJ, Fear MW, Crowe MM, et al. Identification of factors predicting scar outcome after burn 
injury in children: a prospective case-control study. Burns Trauma. 2017;5:19. 
Yalcin I, Bump R. Validation of two global impression questionnaires for incontinence. Am J Obstet 
Gynecol. 2003;189:98-101. 
Zouboulis CC, Tzellos T, Kyrgidis A, et al. Development and validation of the International Hidradenitis 
Suppurativa Severity Score System (IHS4), a novel dynamic scoring system to assess HS severity. Br J 
Dermatol. 2017 Nov;177(5):1401-1409.  
Zalaudek I, Argenziano G, Mordente I, et al. Nevus type in dermoscopy is related to skin type in white 
persons. Arch Dermatol. 2007;143(3):351-356. 
 
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 Agree to use a male condom plus partner use of a contraceptive method with a failure rate of 
< 1% per year when having penile-vaginal intercourse with a WOCBP who is not currently 
pregnant. 
In addition, male subjects must refrain from donating sperm for the duration of the study and for 
220 days (which includes the duration of relevant exposure plus the duration of sperm cycle) 
after the last dose of study treatment. 
Male subjects with a pregnant or breastfeeding partner must agree to remain abstinent from 
penile-vaginal intercourse or use a male condom during each episode of penile penetration for 
the duration of the study and for 220 days (which includes the duration of relevant exposure plus 
the duration of sperm cycle) after the last dose of study treatment. 
Female subjects 
Female subjects of childbearing potential are eligible to participate if they agree to use highly 
effective methods of contraception consistently and correctly as described in the table below and 
during the protocol-defined time frame in Section 5.1, and refrain from donating oocytes for 
assisted reproduction during this period. For WOCBP, hormonal contraceptives must be used 
without schedule changes and in steady doses during the study treatment. Starting hormonal 
contraceptives during the study is not permitted. 
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Highly Effective Contraceptive Methods: 
Highly Effective Contraceptive Methods That Are User Dependent a  
Failure rate of <1% per year when used consistently and correctly.  
 Combined (estrogen and progestogen containing) hormonal contraception associated with inhibition 
of ovulation 
o Oral 
o Intravaginal 
o Transdermal 
 Progestogen only hormonal contraception associated with inhibition of ovulation 
o Oral 
o Injectable  
Highly Effective Methods That Are User Independent a  
 Implantable progestogen only hormonal contraception associated with inhibition of ovulation 
o Intrauterine device (IUD) 
o Intrauterine hormone-releasing system (IUS) 
o Implants inserted beneath the skin 
 Bilateral tubal ligation or occlusion 
Vasectomized Partner  
A vasectomized partner is a highly effective birth control method provided that the partner is the sole 
male sexual partner of the WOCBP and the absence of sperm has been confirmed. If not, an additional 
highly effective method of contraception should be used.  
Sexual Abstinence  
Sexual abstinence is considered a highly effective method only if defined as refraining from heterosexual 
intercourse during the entire period of risk associated with the study treatment. The reliability of sexual 
abstinence needs to be evaluated in relation to the duration of the study and the preferred and usual 
lifestyle of the subject.  
a Typical use failure rates may differ from those when used consistently and correctly. Use should be consistent 
with local regulations regarding the use of contraceptive methods for subjects participating in clinical studies.  
Pregnancy Testing: 
Women of childbearing potential should only be included after a confirmed menstrual period and 
a negative highly sensitive serum pregnancy test at screening and urine pregnancy test on Day 1 
(prior to study treatment administration). 
Additional pregnancy testing should be performed as mentioned in the SoA (Section 1.3). 
Pregnancy testing will be performed whenever a menstrual cycle is missed or when pregnancy is 
otherwise suspected. Positive urine pregnancy test result should be confirmed with serum test. 
Collection of Pregnancy Information 
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Male subjects with partners who become pregnant  
The Investigator will attempt to collect pregnancy information on any male subject’s female 
partner who becomes pregnant while the male subject is in this study. This applies only to male 
subjects who receive study treatment. 
After obtaining the necessary signed informed consent from the pregnant female partner directly, 
the Investigator will record pregnancy information on the appropriate pregnancy form and 
submit it to the pharmacovigilance unit within 24 hours of learning of the partner’s pregnancy. 
The female partner will also be followed to determine the outcome of the pregnancy. Information 
on the status of the mother and child will be forwarded to AnaptysBio. Generally, the follow-up 
will be no longer than 6 to 8 weeks following the estimated delivery date. Any termination of the 
pregnancy will be reported regardless of fetal status (presence or absence of anomalies) or 
indication for the procedure.  
Any SAEs associated with the pregnancy in the male subject’s partner should also be reported to 
the pharmacovigilance unit within 24 hours of the event using the back-up Paper Report Form. 
Female subjects who become pregnant  
The Investigator will collect pregnancy information on any female subject who becomes 
pregnant while participating in this study. Information will be recorded on the appropriate form 
and submitted to the pharmacovigilance unit within 24 hours of learning of a subject’s 
pregnancy. The subject will be followed to determine the outcome of the pregnancy. The 
Investigator will collect follow-up information on the subject and the neonate and the 
information will be forwarded to AnaptysBio. Generally, follow-up will not be required for 
longer than 6 to 8 weeks after the delivery date. Any termination of pregnancy will be reported, 
regardless of fetal status (presence or absence of anomalies) or indication for the procedure. 
While pregnancy itself is not considered to be an AE or SAE, any pregnancy complication or 
elective termination of a pregnancy will be reported as an AE or SAE. A spontaneous abortion is 
always considered to be an SAE and will be reported as such. 
Any poststudy pregnancy related SAE considered reasonably related to the study treatment by 
the Investigator will be reported to AnaptysBio as described in Section 8.2.1.8. While the 
Investigator is not obligated to actively seek this information in former subjects, he or she may 
learn of an SAE through spontaneous reporting.  
Any female subject who becomes pregnant while participating in the study will be withdrawn 
from the study. 
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9. Over the last week, how much has your  skin caused any sexual 
difficulties? 
 
Very much
A lot 
A little 
Not at all 




 
 
 
Not relevant 
10 Over the last week, how much of a problem has the treatment 
for your skin been, for example by making your home messy, or 
by taking up time? 
Very much
A lot 
A little 
Not at all 




 
 
 
Not relevant 
©AY Finlay, GK Khan, April 1992 www.dermatology.org.uk. 
Please check you have answered EVERY question. Thank you. 
If two or more questions are left unanswered the questionnaire is not scored. If two or more response 
options are ticked, the response option with the highest score should be recorded. If there is a response 
between two tick boxes, the lower of the two score options should be recorded. 
 
 
Scoring: 
Very much  
3 points 
A lot   
2 points 
A little   
1 point 
Not at all  
0 points 
Not relevant  
0 points 
Question 7, ‘prevented work or studying’  
3 points 
The DLQI is calculated by summing the score of each question resulting in a maximum of 30 and 
a minimum of 0. The higher the score, the more quality of life is impaired.  
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Laboratory 
Assessments 
Parameters 
Urinalysis 
Bilirubin 
pH
Blood
Protein
Glucose
Specific gravity
Ketones
Urobilinogen
Leukocytes 
 
Nitrites
 
Microscopy (At discretion of Investigator 
based on urinalysis results)
Viral serology and 
testing 
Antibodies to hepatitis B core antigen 
Hepatitis B surface antigen
Hepatitis C antibody and reflex RNA
Human immunodeficiency virus 
antibodies
 
Tuberculosis (TB) 
screening
QuantiFERON-TB Gold® In-Tube, the third-generation test (If the test indeterminate 
it can be retested only once)
NOTES: Please see SoA for laboratory tests time points. 
All blood samples must be drawn prior to administration of the study treatment, unless otherwise specified. The 
date and exact time of sample collection must be recorded.
 
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