Placebo-Controlled Proof of Concept Study to Investigate ANB020 Activity in Adult Patients With Peanut Allergy
Phase: PHASE2
Conditions: Peanut Allergy
Sponsor: AnaptysBio, Inc.

AnaptysBio Inc. 
 
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Protocol Number: ANB020-003 
ANB020 
01 DEC 2017 
Confidential 
Clinical Study Protocol 
Protocol Title:  
Placebo-Controlled Proof of Concept Study to Investigate 
ANB020 Activity in Adult Patients with Peanut Allergy 
Protocol Number: 
ANB020-003 
Version: 
Amendment 5 
Date of Protocol:  
01 DEC 2017 
Product:  
ANB020 
IND No.:  
126765 
Study Phase  
II 
Sponsor: 
AnaptysBio Inc. 
10421 Pacific Center Court, Suite 200, San Diego, CA 92121, 
United States 
Project Manager: 
AnaptysBio Inc. 
10421 Pacific Center Court, Suite 200, San Diego, CA 92121 
United States 
Email: 
Phone:
Medical Monitor: 
AnaptysBio Inc. 
10421 Pacific Center Court, Suite 200, San Diego, CA 92121 
United States 
Email:
Phone:
Principal Investigator: 
Stanford University Medical Center 
Sean N Parker Center for Allergy Research at Stanford 
University, EL Camino Hospital, 2500 Grant Road, 4th Floor, 
Tower C, Mountain View, CA 94040 
United States 
Email:
Phone:
Confidentiality Statement 
This confidential information in this document is provided to you as an Investigator or consultant for review by you, your staff, and the applicable 
Institutional Review Board. Your acceptance of this document constitutes agreement that you will not disclose the information contained herein 
to others without written authorization from the Sponsor. 

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SYNOPSIS 
Name of Sponsor/Company: 
AnaptysBio Inc. 
Name of Finished Product: 
Humanized immunoglobulin subtype G1/kappa (IgG1/kappa) 
monoclonal antibody 
Name of Active Ingredient: 
ANB020 
Title of Study: 
Placebo-Controlled Proof of Concept Study to Investigate ANB020 Activity in Adult 
Patients with Peanut Allergy 
Protocol No: 
ANB020-003 
Study center: 
Up to 3 centers in the US 
Study duration:  
The expected duration of the study is approximately 66 days (Screening 
period of 21 days, Treatment period of 15 days, and Follow-up period of 
30 days). 
Phase: 
II 
Objectives: 
Primary: 
• To assess the safety and tolerability of single dose administration of ANB020 in adult patients with 
peanut allergy. 
• To measure the response of adult patients with peanut allergy on Day 14 following an oral blind 
placebo-controlled food challenge (BPCFC) threshold and cumulative peanut dose tolerated after 
administration of ANB020 or placebo compared to cumulative baseline peanut BPCFC. 
Secondary: 
• To compare the symptoms to peanut antigen challenge on Day 14 using the Oral Food Challenge 
(OFC) Symptoms Scoring Assessment Tool after administration of ANB020 or placebo compared 
to baseline peanut BPCFC symptoms. 
• To describe the limited pharmacokinetics (PK) of ANB020 following a single, intravenous (IV) dose. 
Exploratory: 
• To assess the effect of ANB020 on circulating serum cytokines. 
• To assess the effect of ANB020 on leukocytes within whole blood. 
• To compare the immune response of ANB020 to placebo dosed patients in the ex vivo peanut antigen 
challenge. Stanford University Only 
• To measure the response of adult patients with peanut allergy on Day 45 following an oral BPCFC 
threshold and cumulative peanut dose tolerated after administration of ANB020 or placebo compared 
to cumulative baseline peanut BPCFC. 
• To compare the symptoms to peanut antigen challenge on Day 45 using the OFC Symptoms Scoring 
Assessment Tool after administration of ANB020 or placebo compared to baseline peanut BPCFC 
symptoms. 
Methodology:  
This will be a proof of concept study aiming to assess the safety and tolerability of ANB020 in adult patients 
with peanut allergy. This study will also investigate the effects of ANB020 or placebo in adult patients with 
peanut allergy following an oral BPCFC at 2 and 6 weeks post ANB020 or placebo administration. The 
effects of ANB020 on the immune response to peanut upon ex vivo peanut antigen challenge will be 
evaluated in Stanford University patients 
Informed consent must be obtained prior to participation in the study.  At the screening visit (7-21 days 
before Day 1), inclusion/exclusion criteria is assessed, each eligible patient will be administered a graded 
peanut and placebo oral food challenge (BPCFC) according to the PRACTALL consensus report. Vital signs, 
physical examination findings, and subjective symptoms during the BPCFC will be monitored per 

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PRACTALL guidelines using the OFC Symptom Scoring Assessment Tool. The oral challenge should be 
stopped when the patient develops clinically significant symptoms indicative of an allergic reaction as per the 
Investigator’s assessment. The total cumulative dose of blinded peanut/placebo tolerated and dosing 
step/threshold reached prior to the reaction will be recorded. Patients will be observed in the study center 
until the Investigator determines that the patient is clinically stable and can be discharged. The oral food 
challenge (BPCFC) can be completed in 2 days if the Investigator feels that it is the best for patient’s safety 
and convenience. Otherwise all patients will undergo the peanut challenge and placebo challenge on the same 
day. Blood samples collected from Stanford University patients for pharmacodynamic (PD) assessments (ex 
vivo whole blood peanut antigen challenge) will be collected to determine the intensity of response and 
establish a baseline value of peanut antigen induced immune activation. Medical history and various other 
safety assessments including laboratory and biomarker analysis (cytokines) will be performed.  
On Day 1, the patients will return to the study center and the inclusion and exclusion criteria will be 
reviewed. Eligible patients will be randomized to receive one intravenous dose of either ANB020 
(300 mg/100 mL) or placebo (0.9% sodium chloride [100 mL]) in a 3:1 ratio. Specific laboratory and safety 
assessments will be performed, and serial samples for PK analysis will be collected. Patients with any 
ongoing adverse events (AEs) or serious adverse events (SAEs) at the time of scheduled discharge from the 
study center should remain at the study center until the Investigator has determined that these events have 
been resolved or deemed as not clinically significant by the Investigator. 
On Day 2 and Day 5, the patients will return to the study center and the samples for PK, biomarker analysis 
(cytokines), and whole blood for leukocytes will be collected and other safety assessments will be performed.  
In addition, whole blood samples from Stanford University patients for ex vivo peanut antigen challenge 
assay will be obtained to determine the peanut antigen induced activation.  
On Day 14, the patients will return to the study center and the peanut and placebo oral food challenge 
(BPCFC) will be performed according to the PRACTALL guidelines. Symptoms will be monitored using the 
OFC Symptom Scoring Assessment Tool and other safety assessments will be performed. The oral challenge 
should be stopped when the patient develops clinically significant symptoms indicative of an allergic reaction 
as per the Investigator’s assessment. The total cumulative dose of blinded peanut/placebo tolerated and 
dosing step/threshold reached prior to reaction will be recorded. Patients will be observed until the 
Investigator determines that the patient is clinically stable and can be discharged. The oral BPCFC (peanut 
challenge and placebo challenge) can be completed in 2 days (one challenge on Day 14 and the second 
challenge on Day 15) if the Investigator feels that it is the best for patient’s safety and convenience. 
Otherwise all patients will undergo the challenges (peanut challenge and placebo challenge) on Day 14 itself. 
On Day 15, patients will return to the study center and the laboratory and safety assessments will be 
performed. The oral food challenge will be continued on Day 15 if the patient has received only the placebo 
challenge on Day 14 and the blood samples scheduled on Day 15 will be collected on Day 16 (only 
applicable if the Investigator decides to complete the challenge in 2 days). After completing the oral food 
challenge (BPCFC), all patients will be in the follow-up period for 30 days. During the 30 days follow-up 
period, the patients will be contacted weekly via telephone by study staff to assess the patient’s well-being.  
On Day 45, the patients will return to the study center for the End of Study (EOS) visit. If any objective 
reaction occurred at Day 14/15 the BPCFC (peanut and placebo oral food challenge) will not be required but 
may be performed at the discretion of the PI. If the Investigator decides to perform the challenge, the 
procedures will be the same as the Day 14/15 visit. The BPCFC will be performed according to the 
PRACTALL guidelines. Symptoms will be monitored using the OFC Symptom Scoring Assessment Tool 
and other safety assessments will be performed. The oral challenge should be stopped when the patient 
develops clinically significant symptoms indicative of an allergic reaction as per the Investigator’s 
assessment. The total cumulative dose of blinded peanut/placebo tolerated and dosing step/threshold reached 
prior to reaction will be recorded. Patients will be observed until the Investigator determines that the patient 
is clinically stable and can be discharged. The oral BPCFC (peanut challenge and placebo challenge) can be 
completed in 2 days (one challenge on Day 45 and the second challenge on Day 46) if the Investigator feels 
that it is the best for patient’s safety and convenience. Otherwise all patients will undergo the challenges 
(peanut challenge and placebo challenge) on Day 45/EOS visit itself. Other procedures scheduled for the 
EOS visit will also be performed on Day 45. 

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Planned number of patients: 
20 
Diagnosis and 
main criteria for inclusion: 
Male or female patients (women of childbearing potential must be 
taking adequate contraceptive measures) aged >18 years with a 
confirmed clinical diagnosis of peanut allergy 
Test product, dose and mode of 
administration: 
ANB020 is a humanized immunoglobulin subtype G1/kappa 
(IgG1/kappa) monoclonal antibody that specifically neutralizes the 
biological effects of human interleukin-33 (hIL-33). 
A single dose of 300 mg ANB020 will be administered by IV infusion 
in polyvinyl chloride or polyolefin bags following dilution to a total 
volume of 100 mL with 0.9% sodium chloride. 
Placebo, dose, and mode of 
administration: 
A total dose of 100 mL of placebo (0.9% sodium chloride) will be 
administered IV on Day 1. 
Criteria for evaluation: 
Primary Safety and Tolerability Endpoints: 
• 
Assessment of AEs/SAEs (potentially significant and clinically important AEs, SAEs, and AEs 
leading to withdrawal). 
• 
Physical examinations. 
• 
Vital signs. 
• 
Clinical safety laboratory tests (hematology, biochemistry, and urinalysis). 
• 
Electrocardiogram (ECG). 
Primary Efficacy Endpoint: 
• 
Difference in total cumulative tolerated peanut dose during BPCFC between baseline and 
post-treatment with ANB020 or placebo on Day 14. 
Secondary Endpoints: 
The following efficacy and PK parameters will be assessed under secondary endpoints. 
Secondary Efficacy Endpoint 
• 
Clinical scores of OFC Symptom Scoring Assessment Tool on Day 14. 
Pharmacokinetic Endpoints: 
A limited sampling strategy to collect samples of whole blood will be implemented for the determination of 
ANB020 in human serum for PK assessment. Where possible, the following PK parameters will be 
determined for ANB020 after a single IV infusion: 
• 
Maximum observed concentration (Cmax). 
• 
Time to maximum observed concentration (tmax). 
Exploratory Pharmacodynamic Endpoints: 
• 
Serum cytokines will be evaluated including, but not be limited to, IL-4, IL-5, IL-9, IL-13, IL-33 and 
sST2. 
• 
Differential white blood cell counts (WBC) in the whole blood will be measured to monitor circulating 
leukocyte populations. 
• 
For the ex vivo peanut antigen challenge, the whole blood peanut response assay will measure the 
cytokine levels released from pathogenic T cells. (Stanford University Only) 
Exploratory Efficacy Endpoints: 
• 
Difference in total cumulative tolerated peanut dose during BPCFC between baseline and 
post-treatment with ANB020 or placebo on Day 45. 
• 
Clinical scores of OFC Symptom Scoring Assessment Tool on Day 45. 
Statistical methods: 

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A total of approximately 20 patients will be randomized in a 3:1 ratio to receive ANB020 or placebo. 
For primary safety and tolerability, AEs, SAEs, vital signs, physical examinations, ECGs, and clinical 
laboratory assessments at specific time points will be evaluated. All safety data will be summarized 
descriptively. Number and percentage of AEs will be presented for each treatment by preferred term and 
system organ class of the current Medical Dictionary for Regulatory Authorities (MedDRA) dictionary. 
Individual listings of all SAEs and AEs leading to discontinuation from the investigational product (IP) will 
be summarized using the current MedDRA dictionary. Similar analyses will be performed for potentially 
significant and clinically important AEs. 
For primary efficacy endpoint, total cumulative tolerated peanut dose on Day 14, and for secondary efficacy 
and exploratory endpoints, the OFC symptom scores (Day 14 and 45) and total cumulative tolerated peanut 
dose on Day 45 will be summarized using descriptive statistics.  
Change from baseline on Day 14 for tolerated dose and OFC scores will be compared between ANB020 and 
placebo using analysis of covariance (ANCOVA) with treatment as fixed effect and baseline results as 
covariate. Treatment differences will be presented with corresponding p-values for the test of no difference 
and 95% confidence interval (CI). Mixed model for repeated measures will be used to estimate 95% CI for 
the difference between ANB020 and placebo on Day 45 for tolerated dose and OFC scores. This model will 
include treatment, visit, and treatment by visit interaction as fixed effect and baseline results as covariate. 
The data collected at baseline, Day 14, and Day 45 will be used in the model. 
For exploratory endpoints, change from baseline will be evaluated where possible. Actual and change in data 
from baseline will be summarized descriptively for each treatment. Comparison between ANB020 and 
placebo will be performed using a mixed model for repeated measures with treatment, time point of 
measurement, and treatment by time point interaction as fixed effects, and baseline results as a covariate. 
Appropriate correlation matrix will be used. All tests of treatment effects will be conducted at a 2-sided alpha 
level of 0.05 or with 2-sided 95% CIs.  
Summaries and listings of vital signs, hematology, clinical chemistry, urinalysis, and ECGs will be presented. 
Appropriate descriptive statistics will be summarized for the observed values at each scheduled assessment 
and for the corresponding change from baseline. Baseline will be the last assessment before administration of 
the IP. 
The PK of ANB020 will be evaluated by assessment of drug concentrations in serum. ANB020 
concentrations will be listed and summarized for each sampling time point using appropriate descriptive 
statistics. The PK parameters will be summarized using appropriate descriptive statistics. 

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TABLE OF CONTENTS 
1.0 
LIST OF ABBREVIATIONS AND DEFINITIONS OF TERMS ....................... 13
2.0 
INTRODUCTION ................................................................................................. 15
2.1 
Background Information ........................................................................... 15
2.2 
Rationale..................................................................................................... 17
2.3 
Hypothesis .................................................................................................. 18
2.4 
Risk-Benefit Assessment ............................................................................ 18
3.0 
STUDY OBJECTIVES.......................................................................................... 20
3.1 
Primary Objectives .................................................................................... 20
3.2 
Secondary Objectives ................................................................................. 20
3.3 
Exploratory Objectives .............................................................................. 20
4.0 
INVESTIGATIONAL PLAN ................................................................................ 21
4.1 
Summary of Study Design ......................................................................... 21
4.2 
Discussion of Study Design ........................................................................ 27
4.3 
Selection of Study Population .................................................................... 28
Inclusion Criteria............................................................................ 2
E[clusion Criteria .......................................................................... 2
Disease Diagnostic Criteria ............................................................ 30
Patient Restrictions......................................................................... 30
Patient :ithdrawal ......................................................................... 3
5.0 
STUDY TREATMENTS ....................................................................................... 32
5.1 
Treatments Administered .......................................................................... 32
5.2 
Identity of Investigational Product ............................................................ 32
5.3 
Packaging and Labelling............................................................................ 32
5.4 
Method of Assigning Patients to Treatment Group.................................. 33
5.5 
Selection of Doses in the Study .................................................................. 33
5.6 
Selection and Timing of Dose for Each Patient ......................................... 33
5.7 
Blinding ...................................................................................................... 33
Blinding ......................................................................................... 33
Unblinding ..................................................................................... 33
Single-Blind Oral )ood Challenge .................................................. 3
5.8 
Prior and Concomitant Treatments .......................................................... 34
E[cluded Medications .................................................................... 3
Allowed Medications ..................................................................... 3
5.9 
Medical Care of Patients after End of Study ............................................ 35
5.10 
Treatment Compliance .............................................................................. 35
5.11 
Investigational Product Accountability ..................................................... 35

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6.0 
STUDY PROCEDURES ....................................................................................... 37
6.1 
Screening .................................................................................................... 37
Oral Blind Placebo-Controlled )ood Challenge .............................. 3
Oral )ood Challenge Symptom Scoring Assessment Tool .............. 3
Skin Prick Testing .......................................................................... 3
6.2 
Study Day Procedures ................................................................................ 40
Blood volume ................................................................................. 0
Day  Randomi]ation .................................................................. 0
Day 2 to Day  ............................................................................. 0
)ollow-up Period............................................................................ 
End of Study .................................................................................. 
Early Termination .......................................................................... 
Timing of Procedures ..................................................................... 
Discharge from the Study Center .................................................... 2
7.0 
SAFETY, PHARMACODYNAMIC, AND PHARMACOKINETIC 
ASSESSMENTS .................................................................................................... 43
7.1 
Safety .......................................................................................................... 43
Adverse Events .............................................................................. 3
... 
Reporting of Adverse Events ........................................ 
...2 
Reporting of Serious Adverse Events to 
Regulatory Authorities and Investigators....................... 
...3 
)ollow-Up of Adverse Events ....................................... 
Clinical Laboratory Evaluations ..................................................... 
9ital Signs, Physical )indings, and Other Safety 
Assessments ................................................................................... 
Safety Monitoring .......................................................................... 
7.2 
Pharmacodynamics .................................................................................... 49
7.3 
Pharmacokinetics ....................................................................................... 50
7.4 
Efficacy....................................................................................................... 50
7.5 
Health Outcomes ........................................................................................ 51
7.6 
Pharmacogenetics ...................................................................................... 51
7.7 
Appropriateness of Measurements ............................................................ 51
8.0 
QUALITY CONTROL AND QUALITY ASSURANCE ..................................... 52
8.1
Monitoring..................................................................................................52
8.2 
Data Management/Coding ......................................................................... 53
8.3 
Quality Assurance Audit............................................................................ 55
9.0 
STATISTICS ......................................................................................................... 56
9.1 
Determination of Sample Size.................................................................... 56
Analysis populations ...................................................................... 
9.2 
Patient Disposition ..................................................................................... 57
9.3 
Patient Characteristics and Concomitant Medications ............................ 57

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9.4 
Safety analyses ........................................................................................... 57
Adverse Events .............................................................................. 
9ital Signs Measurements, Physical )indings, and Clinical 
Laboratory Evaluations .................................................................. 
Missing Data .................................................................................. 
9.5 
Efficacy analysis ......................................................................................... 58
9.6 
Pharmacokinetic Analyses ......................................................................... 59
Evaluation of Pharmacokinetic Data ............................................... 
Pharmacokinetic Concentration Data Analyses ............................... 
Pharmacokinetic Parameter Data Analyses ..................................... 0
9.7 
Pharmacodynamic Analyses ...................................................................... 60
9.8 
Interim Analyses ........................................................................................ 60
10.0 
ETHICS ................................................................................................................. 61
10.1
Institutional Review Board........................................................................61
10.2 
Ethical Conduct of the Study ..................................................................... 61
10.3 
Patient Information and Informed Consent ............................................. 62
10.4 
Patient Data Protection .............................................................................. 62
10.5 
Procedures for Premature Termination or Suspension of the 
Study or the Participation of Investigational Site(s) ................................. 62
11.0 
STUDY ADMINISTRATION ............................................................................... 63
11.1 
ADMINISTRATIVE STRUCTURE ......................................................... 63
11.2 
Data Handling and Record Keeping ......................................................... 63
11.3 
Direct Access to Source Data/Documents.................................................. 64
11.4
Investigator Information ...........................................................................64
Investigator Obligations ................................................................. 
Protocol Signatures ........................................................................ 
Publication Policy .......................................................................... 
11.5 
Financing and Insurance ........................................................................... 65

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12.0 
REFERENCES ...................................................................................................... 66 
13.0 
APPENDIX I .......................................................................................................... 68 
14.0 
APPENDIX II ........................................................................................................ 69 
15.0 
APPENDIX III ....................................................................................................... 72 
16.0 
APPENDIX IV ....................................................................................................... 73 
17.0 
APPENDIX 1: SIGNATURE OF INVESTIGATOR ........................................... 76 
18.0 
APPENDIX 2: PHARMACOKINETIC/WHOLE BLOOD (SERUM) 
BIOMARKER TIME POINTS ............................................................................. 77 
19.0 
APPENDIX 3: SUMMARY OF CHANGES ........................................................ 79 
 

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LIST OF TABLES 
Table 4.1 
Schedule of Events ....................................................................................... 25 
Table 5.1 
Dosing Schedule .......................................................................................... 32 
Table 6.1 
Blood Volume Sampling During Each Visit ................................................. 40 
Table 7.1 
Clinical Laboratory Parameters .................................................................... 48 
Table 11.1 
Administrative Structure .............................................................................. 63 
 

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LIST OF FIGURES 
Figure 4.1 
Schematic of Study Design for Protocol ANB020-003 ................................. 24 
 

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1.0 LIST OF ABBREVIATIONS AND DEFINITIONS OF 
TERMS 
Abbreviation 
Definition 
AD 
Atopic dermatitis 
ADR 
Adverse drug reaction 
AE 
Adverse event 
ANCOVA 
Analysis of covariance 
BMI 
Body mass index 
BP 
Blood pressure 
CI 
Confidence interval 
Cmax 
Maximum observed concentration 
CV 
Coefficient of variation 
BPCFC 
Blind placebo-controlled food challenge 
ECG 
Electrocardiogram 
eCRF 
Electronic case report form 
EDC 
Electronic data capture 
EpiPen 
Epinephrine 
EOS 
End of Study 
ET 
Early Termination 
FSH 
Follicle stimulating hormone 
GCP 
Good Clinical Practice 
gCV 
Geometric coefficient of variation 
GINA 
Global Initiative for Asthma Assessment 
Gmean 
Geometric mean 
GMP 
Good Manufacturing Practice 
hIL-33 
Human interleukin-33 
HR 
Heart rate 
ICF 
Informed Consent Form 
ICH 
International Council for Harmonisation 
ICU 
Intensive care unit 
IgE 
Immunoglobulin E 
IL 
Interleukin 

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IP 
Investigational product 
IRB 
Institutional Review Board 
IV 
Intravenous(ly) 
LLOQ 
Lower limit of quantification 
mAb 
Monoclonal antibody 
MAD 
Multiple ascending dose 
MedDRA 
Medical Dictionary for Regulatory Activities 
n 
Sample size or number of observations 
OFC 
Oral Food Challenge 
PD 
Pharmacodynamic 
PI 
Principal Investigator 
PK 
Pharmacokinetic 
SAE 
Serious adverse event 
SAD 
Single ascending dose 
SAP 
Statistical analysis plan 
SAS 
Statistical analysis system 
SC 
Subcutaneous 
SD 
Standard deviation 
SOP 
Standard operating procedure 
SST 
Serum separator tube 
ST2 
Surface receptor 2 
t1/2 
Terminal half-life 
TEAE 
Treatment emergent adverse event 
Th2 
T helper-2 
tmax 
Time to maximum observed concentration 
U.S. 
United States 
WBC 
White blood cell 

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2.0 INTRODUCTION 
ANB020 is a first-in-class, anti-interleukin-33 therapeutic antibody to treat T helper-2 (Th2) cell 
driven inflammatory diseases with underlying interleukin-33 (IL-33) dysregulation. ANB020 is a 
humanized immunoglobulin subtype G1/kappa (IgG1/kappa) monoclonal antibody (mAb) that 
specifically neutralizes the biological effects of human IL-33 (hIL-33). Interleukin-33, a member 
of the IL-1 superfamily,1 is a multifunctional cytokine that plays an important role in 
Th2-mediated cellular immunity and in the pathogenesis of atopic diseases.2,3 ANB020 binds to 
and inhibits the interaction of IL-33 with its specific cell-surface receptor (ST2) thereby blocking 
IL-33-driven downstream signalling and subsequent cellular responses. It is being developed for 
the treatment of atopic diseases such as asthma, food allergies, and atopic dermatitis (AD). 
2.1 
Background Information 
Worldwide, the prevalence of peanut allergy is quite variable with the highest rates (1-2% in 
adults) being observed in western countries, more specifically the United States (U.S.), United 
Kingdom, Canada and Australia.4 Peanut allergy was once rare, but it is now the leading cause of 
fatal food-allergic reactions.5 It tends to present at a median age of 14-24 months and continues 
through to adulthood. 6For many patients, reactions become more severe on subsequent 
exposure. Unlike allergies to cow’s milk and egg and similar to allergies to fish, shell fish and 
tree nuts, allergy to peanuts rarely resolves spontaneously.4 Compared to other food allergies, 
peanuts cause particularly severe reactions, including a high risk of anaphylactic shock which in 
extreme cases, can cause death of some peanut allergy patients. Moreover, in some cases only a 
very small dose (0.1-1 mg) is required to cause a systemic reaction.4 
As for all atopic disorders, high levels of immunoglobulin E (IgE), and peanut protein-specific 
IgE, have been described in peanut allergy patients. Current therapy involves education around 
the avoidance of peanuts in foods, which can be problematic given the wide and frequently 
hidden use of peanut as a food ingredient, and prompt recognition and treatment of anaphylactic 
reactions as soon as they occur. The only effective treatment for anaphylaxis is intramuscular 
epinephrine (EpiPen) administration, whilst oxygen, nebulized albuterol, systemic 
corticosteroids and histamine H1 and/or H2 receptor antagonists can help alleviate secondary 
symptoms. Therefore, many immunotherapeutic approaches, mainly based on antigen-specific 
(i.e., peanut) desensitization, are being explored to find an effective treatment for this 
life-threatening allergy. In this context, a recent study has shown the benefit of introducing 
peanuts to the diet early in life which may prevent the onset of allergy,7 however for those with 
an established peanut allergy, there is an urgent need for novel and effective treatments. 
Interleukin-33 serum levels are significantly increased in patients pre-disposed to allergic 
diseases who suffer from anaphylactic reactions, suggesting that IL-33 is a contributory factor in 

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the induction of anaphylaxis8 9, thus IL-33 is now considered to be a key mediator in the 
development of allergic disorders via the activation of not only acquired immunity, but also 
innate immunity.10 As ANB020 targets IL-33, it may offer a novel and effective treatment for 
peanut allergy patients. 
Non-clinical studies 
ANB020 is being developed by AnaptysBio Inc. as a lead drug candidate and exhibits strong 
inhibitory activity for human as well as cynomolgus monkey IL-33. Non-clinical data obtained 
from studies with ANB020 in primary human and cynomolgus monkey cells and from in vivo 
non-human primate studies demonstrated that: 
• ANB020 shows reactivity with human and cynomolgus monkey IL-33 (dissociation 
constant of 1 pM versus 37 pM, respectively), but not with mouse or rat IL-33. 
• In primary human and cynomolgus monkey cell populations, from peripheral blood 
mononuclear cells and human whole blood, ANB020 inhibited IL-33-induced 
interferon-gamma production. In human basophils, ANB020 also inhibited IL-33-induced 
IL-5 production. The IC50 was approximately 1-2 nM. 
• The observed serum half-life (t1/2) of ANB020 in cynomolgus monkeys was 160 hours 
after a single intravenous (IV) dose administration, and 187 hours after a single 
subcutaneous (SC) dose administration at 10 mg/kg, consistent with the anticipated 
pharmacokinetic (PK) characteristics for a human IgG1 scaffold mAb in the monkey. 
• A multiple-dose, Good Laboratory Practice-compliant toxicology and toxicokinetics 
study (4-week duration with an 8-week recovery phase) has been conducted with 
ANB020 administered by SC and IV injection to cynomolgus monkeys. This study 
produced no significant test article-related effects and established a No Observed 
Adverse Effect Level of 50 mg/kg. 
These data, together with non-clinical safety data generated, supported a strong scientific 
rationale for advancing ANB020 into clinical development. 
Clinical studies 
A first-in-man Phase I single ascending dose (SAD) and multiple ascending dose (MAD) study 
(ANB020-001) in healthy subjects is being performed. The SAD part of the study has been 
completed. In total, 64 subjects were enrolled. Dosed cohorts included 10, 40, 100, and 300 mg 
SC and 40, 100, 300, and 750 mg IV (n=32 SC route, n=32 IV route). No change in vital signs 
(blood pressure [BP], heart rate [HR], electrocardiogram [ECG], or body temperature) was 
noted. Hematology parameters, such as erythrocytes, white blood cell (WBC) and platelet 

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counts, were all within the normal range and did not show any modification or trend related to 
ANB020 administration. Serum chemistry results were also all in the normal range. A total of 
81% subjects in the placebo group and 79% subjects in the ANB020 group had at least one 
treatment-emergent adverse event (TEAE) during the study. The most commonly reported 
treatment emergent adverse events (TEAEs) were of mild to moderate intensity and by preferred 
term were upper respiratory infection (50% versus 48% in placebo and ANB020 group, 
respectively) and headache (32% versus 27% in placebo and ANB020 group, respectively). One 
serious adverse event (SAE) of decreased neutrophils was reported in the 750 mg dose group 
which resolved without sequelae prior to study completion. No other observations of decreased 
neutrophils were observed. No dose dependent AEs were reported. The PK data from the study 
has been utilized to determine route and dose to be used in this study. The PK data generated 
indicates that a linear PK profile is observed upon ANB020 administration regardless of the 
route. The predicted ANB020 t1/2 is approximately 14 days. Results from emergent data will 
serve as the basis for the route of administration of ANB020 in future studies. 
2.2 
Rationale 
This proof of concept study is intended to explore the activity of ANB020 in adult patients with 
peanut allergy. 
Food allergy, especially peanut allergy, can lead to severe reactions and death in healthy 
individuals. The current standard of care is food allergen avoidance with availability of EpiPen 
for emergency treatment of anaphylaxis resulting from accidental ingestions.11 Although patients 
with food allergies go to great lengths to avoid their allergens, accidental ingestions from 
cross-contamination, mislabelled ingredients or lapses in vigilance do occur.  
There is no approved treatment for the prevention of food allergy reactions at this time. Currently 
various forms of food-specific immunotherapy are under investigation for the prevention of 
reactions to the treated food allergen. This therapy is food allergen specific and side effects to 
treatment are common. Many patients have limited or no response to therapy.12 
Monoclonal antibodies interfering with the atopic pathways involved in food allergy reactions 
have the potential to be non-food specific with fewer side effects. Clinical trials with anti-IgE 
mAbs have demonstrated some benefit for the prevention of food allergy reactions; however, not 
all patients respond to treatment and most responses are partial. There has been interest in 
moving ‘higher’ in the atopic cytokine cascade to improve the response by inhibition of an 
increased number of downstream mediators. Interleukin-33 has been implicated in atopic 
pathways involved in food allergy. Research suggests that IL-33 is one of the initial mediators 
triggering atopic cytokine cascades. Interleukin-33 has also been involved in the magnification 
of the intensity of anaphylactic response. Furthermore IL-33 is considered to be the key cytokine 
setting and sustaining pathogenic (peanut specific) T cells. Therefore, IL-33 inhibition might 

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provide a novel and wide spectrum strategy to benefit patients with peanut, and possibly other 
food allergy. Data on the effect of an anti-IL33 mAb on the resulting atopic immune response in 
food allergy may provide important clues for potential treatment or preventative strategies. 
2.3 
Hypothesis 
This is an exploratory study and no hypothesis testing will be examined. 
2.4 
Risk-Benefit Assessment 
A patient with peanut allergy may or may not benefit from participating in this study. However, 
based upon the inhibition of IL-33 by the investigational product (IP) and pre-clinical study 
results, patients with peanut allergy may benefit. Participation in this study may help develop 
important scientific knowledge that could contribute to the development of a new medication and 
better comprehensive treatment of patients who suffer from AD, asthma, and food allergies. 
ANB020 has been extensively tested in animals, and was found to be safe and well tolerated in a 
Phase I SAD study (ANB020-001) in healthy subjects. In animal studies, there were no ANB020 
related adverse events (AEs) or abnormal ECG findings and the administration of ANB020 had 
no effect on hematology, coagulation, clinical chemistry, or urinalysis test results. In the SAD 
study, 64 healthy subjects were enrolled and dosed. The doses implemented in the SAD study 
were 10, 40, 100, and 300 mg SC and 40, 100, 300, 750 mg IV. No change in vital signs (BP, 
HR, ECG, or body temperature) was noted. Hematology parameters, such as erythrocytes, WBC, 
and platelet counts, were all within the normal range except for one subject in the 750 mg dose 
group. All others did not show any modification or trend related to ANB020 administration. 
Serum chemistry results were also all in the normal range. The most commonly reported TEAEs 
were upper respiratory tract infection (50% versus 48% in placebo and ANB020 group, 
respectively) and headache (32% versus 27% in placebo and ANB020 group, respectively) of 
mild to moderate intensity. No AEs were deemed by the Principal Investigator (PI) to be related 
to ANB020. Of all the AEs reported across all dose groups, 44% were reported as possibly 
related and 36% were reported as unrelated. One SAE of decreased neutrophils was reported in 
the 750 mg dose group which resolved without sequelae prior to study completion. No other 
observations of decreased neutrophils were observed. No dose dependent AEs were reported. 
Although nothing in the testing of ANB020 to date indicates that an allergic reaction is likely; a 
reaction to any drug is possible. Some symptoms of allergic reactions are rash, wheezing or 
difficulty breathing, dizziness or fainting (also a possible outcome of a drop in BP), swelling 
around the mouth, throat or eyes, a fast pulse, or sweating. 

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As ANB020 is a mAb, based on clinical studies with other mAbs, study participants may 
experience symptoms of an apparent allergic reaction to the drug, also known as ‘cytokine 
release syndrome’. The symptoms of this 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 
(e.g., blood and mucus in the lung). 

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3.0 STUDY OBJECTIVES 
3.1 
Primary Objectives 
The primary objectives of the study are as follows: 
• To assess the safety and tolerability of single dose administration of ANB020 in adult 
patients with peanut allergy. 
• To measure the response of adult patients with peanut allergy on Day 14 following an 
oral blind placebo-controlled food challenge (BPCFC) threshold and total cumulative 
peanut dose tolerated after administration of ANB020 or placebo compared to cumulative 
baseline BPCFC. 
3.2 
Secondary Objectives 
The secondary objectives of the study are as follows: 
• To compare the symptoms to peanut antigen challenge on Day 14 using the Oral Food 
Challenge (OFC) Symptoms Scoring Assessment Tool after administration of ANB020 
or placebo compared to baseline peanut BPCFC symptoms. 
• To describe the limited PK of ANB020 following a single, IV dose. 
3.3 
Exploratory Objectives 
• To assess the effect of ANB020 on circulating serum cytokines. 
• To assess the effect of ANB020 on leukocytes within whole blood. 
• To compare the immune response of ANB020 to placebo dosed patients in the ex vivo 
peanut antigen challenge. (Stanford University Only) 
• To measure the response of adult patients with peanut allergy on Day 45 following an 
oral BPCFC threshold and cumulative peanut dose tolerated after administration of 
ANB020 or placebo compared to cumulative baseline peanut BPCFC. 
• To compare the symptoms to peanut antigen challenge on Day 45 using the OFC 
Symptoms Scoring Assessment Tool after administration of ANB020 or placebo 
compared to baseline peanut BPCFC symptoms. 

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4.0 INVESTIGATIONAL PLAN 
4.1 
Summary of Study Design 
This is a Phase II, double-blind, placebo-controlled, proof of concept study to assess the safety 
and tolerability of ANB020 in adult patients with peanut allergy. This study will also investigate 
the effects of ANB020 or placebo in adult peanut allergic patients following an oral BPCFC at 2 
and 6 weeks post ANB020 or placebo administration. The effects of ANB020 on the immune 
response to peanut upon ex vivo peanut antigen challenge will be evaluated in Stanford 
University patients only.  
Informed consent must be obtained prior to participation in the study.  At the screening visit 
(7-21 days before Day 1), inclusion/exclusion criteria is assessed, each eligible patient will be 
administered a graded peanut and placebo oral food challenge (BPCFC) according to the 
PRACTALL consensus report (See Section 6.1.1). Vital signs, physical examination findings, 
and subjective symptoms during the BPCFC will be monitored per PRACTALL guidelines using 
the OFC Symptom Scoring Assessment Tool (See Section 6.1.2). The oral challenge should be 
stopped when the patient develops clinically significant symptoms indicative of an allergic 
reaction as per the Investigator’s assessment. The total cumulative dose of blinded 
peanut/placebo tolerated during the dosing threshold challenge will be recorded. Patients will be 
observed until the Investigator determines that the patient is clinically stable and can be 
discharged. The oral food challenge can be completed in 2 days if the Investigator feels that it is 
the best for patient’s safety and convenience. Otherwise all patients will undergo the peanut 
challenge and placebo challenge on the same day. If the Investigator is planning to complete the 
challenge (BPCFC) in 2 days, he or she needs to follow the procedures and assessments 
pertaining to the challenge on both the days as detailed in Section 6.1.1, 6.1.2, and 7.1.3. Blood 
samples collected from Stanford University patients for pharmacodynamic (PD) assessments 
(ex vivo whole blood peanut antigen challenge) will be collected at screening (prior to BPCFC) 
to determine the intensity of the response and establish a baseline value of peanut antigen 
induced immune activation. Medical history and various other safety assessments including 
laboratory and biomarker analysis (cytokines) will be performed. 
On Day 1, the patients will return to the study center and the assessment for inclusion and 
exclusion criteria will be reviewed. Eligible patients will be randomized to receive one 
intravenous dose of either ANB020 (300 mg/100 mL) or placebo (0.9% sodium chloride 
[100 mL]) in a 3:1 ratio. Specific laboratory and safety assessments will be performed. Serial 
samples for PK analysis will be collected according to Section 18.0. Patients with any ongoing 
AEs or SAEs at the time of scheduled discharge from the study center should remain at the study 
center until the Investigator has determined that these events have been resolved or deemed as 
not clinically significant by the Investigator. 

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On Day 2 and Day 5, the patients will return to the study center and the samples for PK, 
biomarker analysis (cytokines), and whole blood for leukocytes will be collected, and other 
safety assessments will be performed.  In addition, whole blood samples from Stanford 
University patients for ex vivo peanut antigen challenge assay will be obtained to determine the 
peanut antigen induced activation.  
On Day 14, the patients will return to the study center and the oral BPCFC will be administered. 
Symptoms will be monitored using the OFC Symptom Scoring Assessment Tool and other safety 
assessments will be performed. The oral challenge should be stopped when the patient develops 
clinically significant symptoms indicative of an allergic reaction as per the Investigator’s 
assessment. The total cumulative dose of blinded peanut/placebo tolerated and dosing 
step/threshold reached prior to reaction will be recorded. Patients will be observed until the 
Investigator determines that the patient is clinically stable and can be discharged. The oral 
BPCFC (peanut challenge and placebo challenge) can be completed in 2 days (one challenge on 
Day 14 and the second challenge on Day 15) if the Investigator feels that it is the best for 
patient’s safety and convenience. Otherwise all patients will undergo the challenges (peanut 
challenge and placebo challenge) on Day 14 itself.  
On Day 15, patients will visit the study center and the laboratory and safety assessments will be 
performed. The oral food challenge will be continued on Day 15 if the patient has received only 
the placebo challenge on Day 14 and the blood samples scheduled on Day 15 will be collected 
on Day 16 (only applicable if the Investigator decides to complete the challenge in 2 days). The 
Investigator must follow the procedures and assessments pertaining to the challenge on both 
Day 14 and Day 15 as detailed in Section 6.1.1, 6.1.2, and 7.1.3. After completing the oral food 
challenge, all patients will be in the follow-up period for 30 days. During the 30 days follow-up 
period, the patients will be contacted weekly via telephone by study staff to assess the patient’s 
well-being.  
On Day 45, the patients will return to the study center for the End of Study (EOS) visit. If any 
objective reaction occurred at Day 14/15, the BPCFC (peanut and placebo oral food challenge) 
will not be required but may be performed at the discretion of the Investigator.  If the 
Investigator decides to perform the challenge, the procedures will be the same as the Day 14/15 
visit. The BPCFC may be performed on Day 45 according to the PRACTALL guidelines. 
Symptoms will be monitored using the OFC Symptom Scoring Assessment Tool and other safety 
assessments will be performed. The oral challenge should be stopped when the patient develops 
clinically significant symptoms indicative of an allergic reaction as per the Investigator’s 
assessment. The total cumulative dose of blinded peanut/placebo tolerated and dosing 
step/threshold reached prior to reaction will be recorded. Patients will be observed until the 
Investigator determines that the patient is clinically stable and can be discharged. The oral 
BPCFC (peanut challenge and placebo challenge) can be completed in 2 days (one challenge on 

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Day 45 and the second challenge on Day 46) if the Investigator feels that it is the best for 
patient’s safety and convenience. Otherwise all patients will undergo the challenges (peanut 
challenge and placebo challenge) on Day 45 (EOS visit) itself. Other procedures scheduled for 
the EOS visit will also be performed on Day 45.The study design is presented in Figure 4.1 and 
the Schedule of Events is presented in Table 4.1. 

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Abbreviations: BPCFC = Blind placebo-controlled food challenge; ECG = electrocardiogram; EOS: End of Study; ET = Early Termination; FSH = follicle stimulating hormone; 
IL = interleukin; IP = investigational product; OFC = Oral Food Challenge; PK = pharmacokinetics; WOCBP = Women of childbearing potential 
a 
Confirm informed consent and continued willingness to participate. 
b 
See Section 6.1.1 and 7.1.3 for the instructions to record vital signs, physical examination, and clinical evaluations using the OFC Symptom Scoring Assessment Tool 
during BPCFC. 
c 
See Table 7.1 for safety laboratory details (Virology, Quantiferon Gold® test, and drugs of abuse to be performed at screening only). 
d 
See Section 18.0 (Appendix 2) for schedule of PK collection time points. 
e 
See Section 18.0 (Appendix 2) for schedule of peanut challenge assay, biomarker cytokines, and whole blood for leukocytes collection time points. During screening the 
samples for ex vivo peanut antigen challenge, whole blood for leukocytes, and serum samples for cytokines should be collected prior to administration of BPCFC. If 
necessary, the sample for ex vivo peanut antigen challenge can be collected on Day 1(instead of Screening), prior to dosing. Ex vivo Peanut challenge is for Stanford 
University only. 
f 
ET visit will include all procedures to be done at EOS visit as well as any procedures that should be done at the next regularly scheduled visit. ET visit will be performed 
if the patient discontinues the study before EOS visit. If the patient completes all study visits and return to study center for EOS visit on Day 45, ET visit will not be 
applicable. 
g 
Leukocytes will be obtained as part of hematology safety laboratory panel at screening, Day 2, and Day 45/ET. On Day 5 and Day 15, whole blood samples for 
leukocytes will be collected separately as there is no safety laboratory assessment on Day 5 and Day 15. 
h 
Only conduct skin prick test and ImmunoCAP testing if these tests had not been performed within 8 weeks before screening. 
i 
For patients with a history of asthma, spirometry or peak flow will be obtained before starting the initial placebo challenge and again before starting the initial peanut 
challenge . See Section 6.1.1. 
j 
Only applicable if the Investigator decides to complete the oral food challenge in 2 days. See Section 6.1.1 and 7.1.3 for the instructions to record vital signs, physical 
examination, and clinical evaluations using the OFC Symptom Scoring Assessment Tool during BPCFC. 
k 
If the Investigator decides to complete the BPCFC on Day 15, the blood samples for leukocytes (whole blood), biomarker analysis (cytokines), and PK analysis should 
be collected on the following day (Day 16). The patient’s vital signs, adverse events, if any, and concomitant medications will also be recorded on Day 16. 
l 
If any objective reaction occurred at Day 14/15, the BPCFC (peanut and placebo oral food challenge) will not be required but may be performed at the discretion of the 
Investigator 
m 
The FSH levels will be obtained only on postmenopausal patients defined as aged over 45 years with at least 1 year of amenorrhea. Blood samples to determine the FSH 
levels will be obtained only at screening. 
n 
If the Investigator decides to complete the oral food challenge over two days, please refer to Day 46 and appropriate footnotes for guidance. 
o 
If the BPCFC is continued on Day 46, all assessments related to the BPCFC will be performed on Day 46. Concomitant medications and adverse events will also be 
recorded on Day 46. All laboratory/diagnostic tests scheduled for the EOS visit will be performed on day 45. 
P 
If the patient’s ET visit is between Day 35 to 45, and the termination is for non-medical reasons, the BPCFC will be administered during the ET visit. If the ET visit is 
before Day 35, the BPCFC will not be repeated. 
q 
Informed consent must be obtained prior to participation in the study. 
 

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4.2 
Discussion of Study Design 
ANB020 is a first-in-class, anti-IL-33 therapeutic antibody developed by AnaptysBio, to treat 
Th2 cell driven inflammatory diseases with underlying IL-33 dysregulation. Preliminary 
evidence of this compound’s significant PD activity in terms of cytokine modulation has been 
demonstrated in non-clinical and clinical studies, justifying its further development in patients 
with AD. Emergent data of the Phase I study (ANB020-001) in healthy subjects are the basis for 
the dose and IV route of administration of ANB020. The 300 mg IV dose was found to be safe 
and well tolerated in healthy subjects. The SAD part of the study has been completed but the 
MAD part of the study is ongoing. In the SAD part of the study, 64 subjects were enrolled and 
dosed. The doses implemented in the SAD study were 10, 40, 100, and 300 mg SC and 40, 100, 
300, and 750 mg IV. No change in vital signs (BP, HR, ECG, or body temperature) was noted. 
Hematology parameters, such as erythrocytes, WBC and platelet counts, were all within the 
normal range except for one subject in the 750 mg dose group. All others did not show any 
modification or trend related to ANB020 administration. Serum chemistry results were also all in 
the normal range. The most commonly reported TEAEs were upper respiratory tract infection 
(50% versus 48% in placebo and ANB020 group, respectively) and headache (32% versus 27% 
in placebo and ANB020 group, respectively) of mild to moderate intensity. No AEs were 
deemed by the PI to be related to ANB020. Of all the AEs reported across all dose groups, 44% 
were reported as possibly related and 36% were reported as unrelated. One SAE of decreased 
neutrophils was reported in the 750 mg dose group which resolved without sequelae prior to 
study completion. No other observations of decreased neutrophils were observed. No dose 
dependent AEs were reported. 
The dose of ANB020 selected for this study 300 mg/100 mL (IV) has provided complete 
inhibition of IL-33 induced cytokine release (ex vivo) up to 43 days and has been administered 
safely in study ANB020-001. 
Patients with food allergy must consistently avoid food allergens including that which is often 
not readily apparent from visual inspection (cross-contamination during preparation or serving of 
food), to prevent potentially life threatening reactions. These avoidance measures significantly 
affect their quality of life. There are no currently approved treatments to prevent reactions from 
accidental ingestions. The use of targeted immune modulators such as ANB020 may be able to 
reduce the Th2 specific inflammatory cascade that trigger the clinical symptoms of a reaction. 
Other monoclonal Th2 immune modulators such as anti-IgE have shown promising but 
inconsistent results in clinical studies. 
This is a proof of concept study13 aiming to assess the effects of ANB020 compared to placebo 
in patients with peanut allergy and provide evidence that the hypothesized mechanisms is 

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affected by the IP and that the effect on the mechanism leads to a desired short-term clinical 
outcome such as increased tolerance to food peanut antigen challenge.  
This study uses a screening BPC)C to provide a baseline for the assessments performed after 
ANB020 or placebo administration. Patients will receive active ANB020 or placebo in a 3: ratio 
on Day . On Day  and on Day , the oral BPC)C will be administered again. The BPC)C 
may be split into 2 days if the Investigator feels that that it is the best for patient¶s safety and 
convenience. Patients will be followed after ANB020 administration for P., PD, and safety 
assessments from a single dose. 
4.3 
Selection of Study Population 
Eligibility criteria for this study have been carefully considered to ensure the safety of the 
patients included in the study and that the results of the study can be used. It is imperative that 
patients fully meet all of the inclusion criteria and none of the e[clusion criteria. 
 
Inclusion Criteria 
Patients will be enrolled in the study only if they meet all of the following criteria: 
• Male and female patients with age ! years and able to give informed consent. 
• Patients with a confirmed clinically allergic response to peanut. 
• Positive clinical reaction observed during the peanut oral food challenge and no clinical 
reaction observed during the placebo challenge. 
• Positive peanut allergy skin prick test !3 mm of the negative control and detectable 
serum peanut-specific IgE levels !0.3 kUL by ImmunoCAP testing. Skin prick test 
and ImmunoCAP testing will be conducted only if these tests had not been performed 
within  weeks before screening.  
• Body mass inde[ BMI of  to 3 kgm2 inclusive and total body weight !0 kg 
0 lb. BMI   weight kgheight >m2@. 
• :illing and able to comply with the study protocol reTuirements. 
• +ave the ability to read and understand the study procedures and have the ability to 
communicate meaningfully with the Investigator and staff. 
• :omen of childbearing potential, must have a negative serum pregnancy test at screening 
and Day , and be surgically sterile or using an acceptable method of contraception 
throughout the study and for  weeks after the last administration of IP. Postmenopausal 
patients defined as  aged over  years with at least  year of amenorrhea and levels of 

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follicle stimulating hormone )S+ over 20 IUL at screening or 2 aged over 0 years 
with at least  year of amenorrhea. 
• Male patients must be willing to use effective methods of contraception during the entire 
study period and for  weeks after the last administration of IP See Section .3.. 
 
Exclusion Criteria
Patients will not be enrolled in the study if they meet any of the e[clusion criteria: 
• +ave concomitant dermatological or medical conditions which may interfere with the 
Investigator¶s ability to evaluate the patient¶s response to the IP. 
• +ave e[perienced severe life-threatening anaphylactic reactions to peanuts within 
 months before screening i.e., reTuiring an intensive care unit ICU admission. 
• Positive clinical reaction observed during the placebo oral food challenge. 
• Participation in any interventional study for the treatment of peanut andor food allergies 
in the 2 months before screening. 
• +ave received any IP or been part of any interventional clinical study within a period of 
3 months or  half-lives whichever is longer before screening. 
• +ave received systemic corticosteroids, nonsteroidal, immunosuppressant, or 
immunomodulating drugs treatments within 2 weeks before screening. 
• Use of beta blockers, angiotensin-converting en]yme inhibitors, angiotensin-receptor 
blockers, or calcium channel blockers within 2 weeks before screening. 
• +istory of ischemic cardiovascular diseases. 
• Use of biologics such as omali]umab within  months before screening or subject is in 
build-up phase of allergen immunotherapy e[cluding peanut and has not reached 
maintenance dose.  
• +ave received antibiotic treatment within  week before screening. 
• +ave a history of hypersensitivity or allergic reactions following infusions of human 
blood or blood components. 
• +ave a history of hypersensitivity or allergic reactions to polysorbate 0 a component of 
ANB020 formulation or the inactive ingredients e[cipients. 
• If female, are pregnant or lactating, or intend to become pregnant during the study period. 

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• Current diagnosis of asthma reTuiring *lobal Initiative for Asthma Assessment (*INA 
Step  or higher treatment or asthma partially controlled or uncontrolled according to 
*INA classifications in the last three months before screening Appendi[ I. 
• +istory of a life threatening asthma attack within  year before screening e[ample: 
reTuiring an ICU admission, intubation with mechanical ventilation. 
• Other significant medical conditions that in the opinion of the PI, prevent participation in 
the study  
• +istory of drug, alcohol or other substance abuse, or other factors limiting the ability to 
cooperate and to comply with the study protocol. 
• +ave any other physical, mental, or medical conditions which, in the opinion of the 
Investigator, make study participation inadvisable or could confound study assessments. 
• Receipt of a live attenuated vaccine within  weeks before screening. 
• Planned surgery during the study or 30 days before screening. 
 
Disease Diagnostic Criteria 
Adult patients age ! years with a confirmed clinical peanut allergy with a positive skin prick 
test !3 mm compared to the negative control and detectable serum IgE antibodies to peanuts 
!0.3 kUL. 
 
Patient Restrictions 
The following restrictions may affect patient participation in this study: 
• Availability to attend visits according to the protocol. 
• Concomitant medication restrictions as described in Section . and medications that 
should be avoided prior to BPC)C as shown in Appendi[ III. 
• :omen of childbearing potential must use a double-barrier method of contraception 
during the study  days and for  weeks after the last administration of IP. Male 
patients must use effective methods of contraception total abstinence or condom with 
spermicide during the study and for at least  weeks after the last administration of IP. 
)or woman of childbearing potential, abstinence alone is not an acceptable method of 
contraception. 
• Restricted alcohol intake 2 units per week  unit of alcohol is eTuivalent to  ounces 
of beer,  ounces of wine, or  ounce of spirits. 
• Strenuous e[ercise should be avoided up to 2 hours before planned study visits. 

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Patient Withdrawal 
All patients are free to withdraw from participation in the study at any time, for any reason, 
specified or unspecified, and without prejudice to further treatment. The inclusion and e[clusion 
criteria are to be followed e[plicitly. If a patient who does not meet the criteria is inadvertently 
enrolled, that patient should be withdrawn from the study. AnaptysBio and 4uintilesIMS must 
be contacted, and if the patient has received ANB020 or placebo, the patient must be followed up 
until EOS Day  for any AEs andor SAEs. 
In addition, the patients will be withdrawn from the study under the following circumstances: 
• 
Prior to IP administration, the Investigator decides that the patient should be withdrawn or is 
at risk. If this decision is made because of an AE or a clinically significant laboratory value, 
the IP should not be administered and appropriate measures are to be taken. AnaptysBio 
andor 4uintilesIMS is to be notified immediately. 
• 
The patient is unwilling to continue in the study. 
• 
Lack of compliance with protocol. 
• 
The Investigator or AnaptysBio, for any reason, stops the study. 
• 
If a female patient becomes pregnant. 
• 
New information suggests taking part in the study may not be in the participant¶s best 
interest. 
Patients who discontinue the study early will have early termination ET procedures performed 
as shown in Table ..  Patients who are randomi]ed and dosed with ANB020 or placebo and 
discontinued from the study after Day  will not be replaced.  All patients who discontinue the 
study prior to completing the Day  study assessments will be replaced. 

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5.0 STUDY TREATMENTS 
5.1 
Treatments Administered 
ANB020 is a humanized IgG1/kappa mAb and was selected from a panel of mouse mAb 
humanized by complementarity-determining region-grafting, optimized and matured via 
mammalian cell display and somatic hyper mutation using AnaptysBio’s (SHM)-XELTM system 
to achieve a desired functional inhibitory potency. 
ANB020 will be administered to patients by IV infusion in polyvinyl chloride or polyolefin bags 
following dilution to a total volume of 100 mL with sterile normal saline (0.9% NaCl). Placebo 
will be administered by IV infusion as 100 mL sterile normal saline (0.9% NaCl). Infusions will 
be administered over 1 hour. 
5.2 
Identity of Investigational Product 
ANB020 is manufactured by Patheon of Greeneville, NC., U.S. under Good Manufacturing 
Practice (GMP) regulations. ANB020 is provided as a sterile clear solution in a glass vial for IV 
infusion and contains no preservatives. 
ANB020 vials must be refrigerated at 2°C to 8°C (36°F to 46°F) until the day of use. ANB020 
vials may be stored at room temperature (>8°C to 25°C [46°F to 77°F]) in the undiluted and/or 
diluted state for up to 8 hours. The vials should remain in the bulk cartons during storage and 
until use to provide protection from light. Vial contents should not be frozen or shaken. They are 
intended for single-use only; therefore, any remaining solution should be discarded. 
The placebo contains no active drug and will be sterile normal saline (0.9% NaCl) for injection. 
The placebo will be procured from the pharmacy stock supply. 
Table 5.1 provides an outline of the dosing schedule for the study. 
Table 5.1 
Dosing Schedule 
Investigational product 
Dosage form and strength 
Manufacturer 
ANB020 
IV infusion: 300 mg/100 mL once on Day 1 
Patheon 
Abbreviation: IV = intravenous 
5.3 
Packaging and Labelling 
Labels will be prepared in accordance with GMP and local regulatory guidelines. 
All IPs should be kept in a secure place under appropriate storage conditions. The IP label on the 
packaging specifies the appropriate storage. 

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5.4 
Method of Assigning Patients to Treatment Group 
This is a randomi]ed, double-blind, placebo-controlled study. On Day , after verification that all 
inclusion and no e[clusion criteria have been met, the patients will be randomi]ed in a 3: ratio 
to ANB020 or placebo. As patients become eligible they will be assigned seTuential 
randomi]ation numbers which will be used to assign the allocated treatment based on a 
randomi]ation schedule. The Sponsor, Investigator, and patients will be blinded to treatment 
assignment of ANB020 or placebo. 4uintilesIMS biostatistician will be responsible for providing 
randomi]ation assignment list to the unblinded pharmacist. 
5.5 
Selection of Doses in the Study 
A single I9 infusion of 300 mg00 mL of ANB020 or 00 mL placebo 0. sodium chloride 
will be administered. 
The dose of ANB020 selected for this study has provided complete inhibition of IL-33 induced 
cytokine release and has been administered safely in study ANB020-00. 
5.6 
Selection and Timing of Dose for Each Patient 
Patients will receive a single dose of ANB020 or placebo administered under supervision at the 
study center. The infusion will be administered at the rate of 00 mL per hour via a Ba[ter 
infusion solutions set )NC20 prime volume  mL or eTuivalent followed by a  mL I9 
saline flush, at the same infusion rate, to ensure that no residual drug remains in the infusion line. 
No in-line filter is to be used. The ANB020 or placebo infusion may be slowed or interrupted for 
patients e[periencing infusion-related AEs. 
5.7 
Blinding 
 
Blinding
This is a randomi]ed, double-blind, placebo-controlled study with limited access to the 
randomi]ation code. The IP and placebo will be identical in physical appearance. The Sponsor, 
Investigator, and patients will be blinded to treatment assignment of ANB020 or placebo. The 
unblinded pharmacy staff will be provided the randomi]ation assignments to prepare the 
assigned IP for each patient. 
 
Unblinding 
The investigator is responsible for ensuring treatment-blinding information is maintained for all 
subjects.  The investigator or hisher designee is responsible for ensuring that disclosure 
envelopes that contain the treatment code are stored safely, that their location is known, and that 

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access is readily available to the relevant staff in case of an emergency.  Unblinding codes will 
be stored at the site by the unblinded pharmacist in case of a medical emergency. 
Unblinding of treatment assignment during the study is discouraged and should occur only if it is 
absolutely necessary to know what treatment the subject received.  If the investigator deems 
identification of the study drug is necessary for the purpose of providing urgent subject care, and 
knowledge of the subject¶s treatment assignment ANB020 or placebo will alter subseTuent 
care, the treatment code for the specific subject will be obtained.  Prior to unblinding, the 
investigator or appropriate designee should attempt to contact the Sponsor¶s Medical Monitor to 
discuss the need to unblind a subject.  In the event the Medical Monitor cannot be reached, the 
investigator should ensure that the unblinding of the treatment code is performed in a discrete 
manner and the treatment is disclosed only to those persons involved with the direct medical care 
of the subject.   The investigator should contact the Sponsor¶s Medical Monitor immediately 
within 2 hours to include weekends following emergency unblinding. Once the subject¶s 
treatment assignment has been obtained in the event of an emergency, the date, time, and reason 
for the unblinding must be recorded in the pharmacy log, on the subject¶s CR) and source notes 
and signed by the investigator.   
 
Single-Blind Oral Food Challenge 
The oral food challenge BPC)C procedure will be single-blind. All patients will be 
administered the placebo challenge first and then proceed with the peanut challenge. The 
Investigator, Sponsor, and pharmacy staff will be unblinded and only the patients will be blinded 
to the oral food challenge assignment i.e., to receive the placebo challenge first or the peanut 
challenge. The Investigator should ensure that the patient reacted to the peanut challenge and 
not the placebo challenge prior to IP administration and continuation in the study. The 
post-dosing BPC)C order should also remain blinded to the patients. 
5.8 
Prior and Concomitant Treatments 
 
Excluded Medications
The following medications will not be permitted during the study. Use of these e[cluded 
medications is a protocol violation and should be recorded in the electronic case report form 
eCR).  
• Treatment with systemic corticosteroids, nonsteroidal, immunosuppressants, or 
immunomodulating drugs within 2 weeks before screening. 
• Treatment with beta blockers, angiotensin-converting en]yme inhibitors, 
angiotensin-receptor blockers, or calcium channel blockers within 2 weeks before 
screening. 

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• Any antibiotic treatment within  week before screening. 
• Use of biologics such as omali]umab within  months before screening or subject is in 
build-up phase of allergen immunotherapy e[cluding peanut and has not reached 
maintenance dose. 
In addition, the medications included in the Appendi[ III should be avoided prior to BPC)C. 
 
Allowed Medications 
Use of EpiPen and other medications as clinically indicated per the PRACTALL guidelines for 
BPC)C reactions See Section ... 
)emales of childbearing potential are to continue using their hormonal contraceptives and 
postmenopausal women are allowed to use hormone replacement therapy. 
The Investigator must record the use of all concomitant medications, both prescribed and 
over-the-counter, into the eCR) and patient¶s medical records. This includes medications used 
on both a regular and an as needed basis. Patients should be discouraged from starting any new 
medication, both prescribed and over-the-counter, without consulting the Investigator, unless the 
new medication is reTuired for emergency use or has been prescribed for clinical need. 
5.9 
Medical Care of Patients after End of Study 
All patients will return to the study center for the EOS Day  or ET visit for final safety and 
EOS assessments. After this visit, patients should be treated according to the Investigator¶s 
clinical judgment. Care after EOSET will not be provided by AnaptysBio. Any significant AE 
which in the opinion of the Investigator is related to the IP, SAE, or pregnancy occurring within 
30 days of the dose of IP should be reported to the safety team of 4uintilesIMS and followed up 
until outcome. 
5.10 Treatment Compliance 
The prescribed dosage, timing, and mode of administration may not be changed. Any deviations 
from the intended regimen must be recorded in the eCR). 
5.11 Investigational Product Accountability 
The Investigator, a member of the investigational staff, or a hospital pharmacist must maintain an 
adeTuate record of the receipt and distribution of all the IPs using the Drug Accountability )orm. 
These forms must be available for inspection at any time. 
All the IP supplies should be accounted for at the termination of the study and a written 
e[planation provided for discrepancies. All unused IP supplies and packaging materials are to be 

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inventoried and returned to QuintilesIMS/AnaptysBio by the Investigator or may be destroyed on 
site following institutions standard operating procedures (SOPs) and proper accountability by 
QuintilesIMS site monitor. The Investigator is not permitted to return or destroy unused IP 
supplies or packaging materials unless authorized by QuintilesIMS. 

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6.0 STUDY PROCEDURES 
Study procedures will be performed as detailed in the Schedule of Events in Table ..
Assessments scheduled on the day of IP administration must be performed prior to the IP 
infusion unless otherwise noted. All assessments will be performed on the day of the specified 
visit however, a window period of  days is available for the Day  visit.  Day  and Day 
 visits should remain consecutive.   A window period of -2 days can be implemented for 
visits occurring after completion of the Day  visit i.e. Day . In addition, the blood 
sample collected from Stanford University patients for the e[ vivo peanut challenge assay 
scheduled at Screening prior to O)C, can be collected on Day  prior to IP administration, if 
necessary.  
6.1 
Screening 
Each potential patient will provide informed consent prior to participation in the study. The 
eligibility of patients will be determined during the screening period. Each eligible patient will 
be administered a graded oral BPC)C according to the PRACTALL consensus report See 
Section ... Symptoms will be monitored using the O)C Symptom Scoring Assessment Tool 
See Section ..2. Blood samples collected from Stanford University patients for PD 
assessments e[ vivo whole blood peanut antigen challenge will be collected See Section .0, 
Appendi[ 2 to determine the intensity of the response and establish a baseline value of peanut 
antigen induced activation. Other screening procedures will be carried out in accordance with the 
Schedule of Events in Table .. 
Oral Blind Placebo-Controlled Food Challenge
The oral BPC)C will be administered in accordance with the PRACTALL consensus report with 
the following parameters.  
The patient should refrain from consuming any meals within 3 hours of the oral food challenge. 
If a light meal is necessary, fatty foods should be avoided. Restricted medications prior to 
proceeding with the O)C should be assessed and verified as per Appendi[ III. Clinical 
evaluations using the O)C Symptom Scoring Assessment Tool and vital signs measurements 
will be done prior to the start of the oral BPC)C. )or patients with a history of asthma, 
spirometry or peak flow will be obtained with the initial vital signs. 
The Investigator must confirm the availability of EpiPen with each patient at screening prior to 
BPC)C and educate the patients to use it when they e[perience any symptom of allergic 
reaction. The patients will be asked to bring the EpiPen to their subseTuent oral food challenges 
BPC)C at the study center. 

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The patients will be administered the placebo challenge first and then proceed with the peanut 
challenge. The patients will not be privy to which challenge (placebo or peanut) is being 
administered. As per the guidelines, all patients need to undergo the challenges (peanut challenge 
and placebo challenge). If the patient develops any signs of an allergic reaction, the challenge 
will be stopped and the patient will be immediately treated accordingly. A standard anaphylaxis 
treatment plan17 is presented in Section 16.0 (Appendix IV). The BPCFC will be done at 
screening, Day 14, and Day 45. The challenge can be completed in 2 days if the Investigator 
feels that it is the best for patient’s safety and convenience, otherwise all patients will undergo 
the peanut challenge and placebo challenge on the same day. All patients will be blinded to the 
challenge assignments. The study staff administering the challenge will be unblinded. 
Peanut flour will be used as the suggested form of testing for peanut allergen. The peanut flour or 
placebo will be mixed with non-allergic food vehicle (i.e., applesauce or pudding) for blinded 
administration. 
The initial dose will be 5 mg of peanut protein or placebo. Doses will be increased stepwise to 
20 mg, 50 mg, 100 mg, 100 mg, 100 mg, and 125 mg to a total of 500 mg cumulative dose. The 
total cumulative dose of blinded peanut/placebo tolerated and dosing step/threshold reached prior 
to the objective reaction will be recorded. 
Dosing intervals will be 20 to 30 minutes. Patient’s vital signs, physical examination, and 
clinical assessments using the OFC Symptom Scoring Assessment Tool (provided in Appendix 
II) will be performed. There will be a 1-2 hour interval between the challenges (peanut challenge 
and placebo challenge). Patients will be observed for 2 hours after the last dose of BPCFC.  
Criteria for Monitoring and Stopping the Oral Food Challenge 
The Investigator or Sub-Investigator (clinician) should be in the study center during BPCFC. 
Monitoring will include recording the vital signs before starting the initial placebo challenge, 
after completion of the placebo challenge, before starting the initial peanut challenge, upon 
completion of the final peanut challenge, and 2 hours after completion of the final peanut 
challenge. (See Section 7.1.3 for more details).  A physical examination will be conducted before 
starting the initial placebo food challenge and upon completion of the final peanut challenge 
(prior to discharge).   For patients with a history of asthma, peak flow or spirometry will be 
collected before starting the initial placebo challenge and again before starting the initial peanut 
challenge. The time of dose administration will be recorded. The OFC Symptom Scoring System 
will be used before starting the initial placebo challenge, after completion of the placebo 
challenge, before starting the initial peanut challenge, upon completion of the final peanut 
challenge, and 2 hours after completion of the final peanut challenge.  

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At the first sign of an objective allergic reaction, the challenge will be stopped and the patient 
will be immediately assessed and treated accordingly. The EpiPen :000 should be readily 
available with the patients at the start of the challenge and the Investigator should confirm the 
availability of other emergency medications and eTuipment I9 fluid, Benadryl, o[ygen, 
Ambubags, etc. at the study center. A standard anaphyla[is treatment plan is presented in 
Section .0 Appendi[ I9. Any treatments given will be recorded along with the time given 
and clinical status of the patient. The patient will continue to be assessed and observed as the PI 
or Sub-Investigator deems appropriate. 
A longer observation period may be warranted prior to proceeding with the ne[t dose or 
discontinuation depending on the patient¶s clinical status and will be at the judgement of the 
Investigator. 
All patients should have an emergency treatment plan available upon discharge from the study 
center regardless of the outcome of the study challenge and an EpiPen readily available. 
 
Oral Food Challenge Symptom Scoring Assessment Tool 
The O)C Symptom Scoring Assessment Tool will be used to assess the patient for common 
symptoms that can be suspected to be an allergic reaction involving the skin, upper respiratory, 
lower respiratory, gastrointestinal, and cardiovascular systems based on a 0-3 scale of absent to 
severe. The O)C Symptom Scoring Assessment Tool is presented in Appendi[ II. 
 
Skin Prick Testing 
Skin prick test and ImmunoCAP testing will be performed only if these tests had not been 
performed within  weeks before screening.
Skin prick testing will be performed only at screening on the fle[or surface of the forearm 
utili]ing standard testing procedures recommended by the American Academy of Allergy, 
Asthma, and Immunology and the American College of Allergy, Asthma, and Immunology -oint 
Practice Parameter on Allergy Diagnostic Testing. Peanut will be tested in the form of a 
commercial e[tract with appropriate positive and negative controls.  
The orthogonal diameter will be measured at the mid-point of the longest a[is and the average of 
the longest and the orthogonal diameter must be calculated. Pseudopodia will not be assessed. 
During screening, the negative control must be 2 mm for the test to be considered valid. If the 
negative control is !2 mm the test should be repeated on another day. 
A wheal that is !3 mm of the negative control will be considered positive. 

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6.2 
Study Day Procedures 
 
Blood volume 
The total blood volume for each Stanford University patient will be appro[imately  mL and 
 mL for non-Stanford patients. The blood volume drawn during each visit is provided in 
Table .. The blood draw for various assessments throughout the study will be performed 
according to safety guidelines established by the National Institutes of +ealth. 
Table 6.1 
Blood Volume Sampling During Each Visit 
Visits 
Screening 
Day 1 
Predose 
Day 1 
Predose 
(PK) 
Day 1 
(0.5H) 
(PK) 
Day 1 
(EOI) 
(PK) 
Day 1 
(EOI 3H) 
(PK) 
Day 2 
Day 5 
Day 14 
Day 
15/16 
Day 45 
Stanford 
Univ. Only 
Total blood 
volume 
sampled 
during each 
visit mLs 
up to  
3-a 
up to 22 
2-22a 
 
 
 
 
3 
2. 
2 
. 
 
Total blood 
volume 
sampled 
during each 
visit mLs 
3 
2 
 
 
 
 
2 
. 
2 
. 
 
Abbreviation: EOI   actual time of end of infusion P.   pharmacokinetics 
a. 
The blood sample for e[ vivo peanut challenge assay appro[imately 0 mL can be collected either at screening or on 
Day . Based on this sample collection, blood volume reTuired at screening and Day  will vary. 
 
Day 1 (Randomization) 
On Day , the patients will be randomi]ed to receive either ANB020 or placebo in a 3: ratio 
 patients will receive ANB020 and  patients will receive placebo. If the blood sample 
collected from Stanford University patients for e[ vivo peanut challenge assay was not collected 
at screening visit it must be collected on Day  prior to IP administration. Additional Day  
procedures will be carried out in accordance with the Schedule of Events in Table .. Patients 
with any ongoing AEs or SAEs at the time of scheduled discharge from the study center should 
remain at the study center until the Investigator has determined that these events have been 
resolved or deemed as not clinically significant by the Investigator. 
 
Day 2 to Day 15 
Patients will return to the study center on Days 2, , , and . 9arious assessments will be 
performed and blood samples will be collected. On Day , oral BPC)C will be administered 
and the symptoms will be monitored See Section .. and Section ..2. The oral BPC)C will 
be continued on Day  if the patient has received only the placebo challenge on Day  and the 

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blood samples scheduled on Day  will be collected on Day  only applicable if the 
Investigator decides to complete the challenge in 2 days. Additional procedures will be carried 
out in accordance with the Schedule of Events in Table ..  
 
Follow-up Period 
After completing the oral food challenge and related procedures post administration of IP, the 
patients will be followed up for another 30 days. During the 30 days follow-up period, the 
patients will be contacted weekly via telephone by study staff to assess the patient¶s well-being. 
Concomitant medications and AESAEs will be recorded in the patient¶s medical source 
documents and eCR)s. 
 
End of Study 
After the follow-up period, all patients will return to the study center for the EOS visit on 
Day . If any objective reaction occurred at Day , the BPC)C will not be reTuired but 
may be performed at the discretion of the Investigator on Day  and the symptoms will be 
monitored See Section .. and Section ..2. If the Investigator decides to perform the 
BPC)C, it can be completed in 2 days one challenge on Day  and the second challenge on 
Day  if the Investigator feels that it is the best for patient¶s safety and convenience. Otherwise 
all patients will undergo the challenges peanut challenge and placebo challenge on Day  
EOS visit itself. All blood samples scheduled for the EOS visit will be collected on Day  
EOS visit regardless of splitting the BPC)C assessments. Additional procedures will be carried 
out in accordance with the Schedule of Events in Table .. 
 
Early Termination 
Patients who discontinue the study early will be asked to return to the study center for the ET 
procedures as shown in the Schedule of Events Table .. Patients will only complete the final 
BPC)C if they discontinue between Day 3 to  for non-medical related reasons. 
 
Timing of Procedures 
There are times where the protocol reTuires more than one procedure to be completed at the 
same time point. In these instances, the following will apply to post-dose time points: 
• The P. samples will take precedence over other procedures and will therefore be 
collected at the nominal time. 
All safety assessments will be timed and performed relative to the start of dosing. 

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Discharge from the Study Center 
A patient will be allowed to leave the study center - hours after the ANB020placebo 
administration at the study center and completion of study-specific procedures providing that: 
• No AEs have been reported during the study visit. 
• The patient responds in the affirmative when asked if they are feeling well. 
If any of these conditions are not met, then the patient will only be allowed to leave the study 
center with the authori]ation of the Investigator or appropriately Tualified delegate. 

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7.0 SAFETY, PHARMACODYNAMIC, AND 
PHARMACOKINETIC ASSESSMENTS 
7.1 
Safety 
Safety assessments will be based on medical review of AE reports, the results of physical 
e[aminations, and clinical laboratory tests. The incidence of observed AEs will be reviewed for 
potential significance and clinical importance. Patients with any ongoing AEs or SAEs at the 
time of scheduled discharge from the study center, should remain at the study center until the 
Investigator has determined that these events have been resolved or deemed as not clinically 
significant by the Investigator. 
 
Adverse Events
The Investigator is responsible for recording all AEs observed during the study screening, 
treatment, and follow-up period. 
Definition of AE: An AE is any untoward medical occurrence in a patient or clinical 
investigation patient administered a pharmaceutical product and which does not necessarily have 
a causal relationship with this treatment. 
Definition of SAE: An SAE, e[perience or reaction, is any untoward medical occurrence 
whether considered to be related to the IP or not that at any dose: 
• 
Results in death. 
• 
Is life-threatening the patient is at a 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. 
• 
ReTuires inpatient hospitali]ation or prolongation of e[isting hospitali]ation: +ospital 
admissions andor surgical operations planned before or during a study are not considered 
AEs if the illness or disease e[isted before the patient was enrolled in the study, provided that 
it did not deteriorate in an une[pected way during the study. 
•
Results in persistent or significant disabilityincapacity. 
• 
Is a congenital abnormalitybirth defect. 
• 
Other: Medically significant events, which do not meet any of the criteria above, but may 
jeopardi]e the patient and may reTuire medical or surgical intervention to prevent one of the 
other serious outcomes listed in the definition above. E[amples of such events are blood 
dyscrasias e.g., neutropenia or anemia reTuiring blood transfusion, etc. or convulsions that 
do not result in hospitali]ation. 

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An adverse drug reaction (ADR) is defined as all noxious and unintended responses to a 
medicinal product related to any dose. 
An unexpected ADR is defined as any adverse reaction, the nature of which is not consistent 
with the applicable product information. 
Each AE is to be evaluated for duration, severity, seriousness, and causal relationship to the IP. 
The action taken and the outcome must also be recorded. 
Severity 
The severity of the AE will be characterized as “mild, moderate, or severe” according to the 
following definitions: 
• 
Mild events are usually transient and do not interfere with the patient’s daily activities. 
• 
Moderate events introduce a low level of inconvenience or concern to the patient and may 
interfere with daily activities. 
• 
Severe events interrupt the patient’s usual daily activity. 
Relationship 
The causal relationship between the IP and the AE has to be characterized as unrelated, unlikely, 
possible, probable, or unknown (unable to judge). 
Events can be classified as “unrelated” if there is not a reasonable possibility that the IP caused 
the AE. 
An “unlikely” relationship suggests that only a remote connection exists between the IP and the 
reported AE. Other conditions, including chronic illness, progression or expression of the disease 
state or reaction to concomitant medication, appear to explain the reported AE. 
A “possible” relationship suggests that the association of the AE with the IP is unknown; 
however, the AE is not reasonably supported by other conditions. 
A “probable” relationship suggests that a reasonable temporal sequence of the AE with drug 
administration exists and, in the Investigator’s clinical judgment, it is likely that a causal 
relationship exists between the drug administration and the AE, and other conditions (concurrent 
illness, progression or expression of disease state, or concomitant medication reactions) do not 
appear to explain the AE. 
All efforts should be made to classify the AE according to the above categories. The category 
“unknown” (unable to judge) may be used only if the causality is not assessable, e.g., because of 
insufficient evidence, conflicting evidence, conflicting data, or poor documentation. 

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7.1.1.1 
Reporting of Adverse Events 
All AEs, regardless of severity occurred during the study (screening, treatment, or follow-up 
period) are to be recorded on the appropriate AE pages (either ‘serious’ or ‘non-serious’) in the 
eCRF. All AEs reported prior to IP administration will also be recorded on the medical history 
CRF page. The Investigator should complete all the details requested including dates of onset, 
severity, action taken, outcome, and relationship to the IP. Each event should be recorded 
separately.  
The ANB020 or placebo infusion may be slowed or interrupted for patients experiencing 
infusion-related AEs. Following the infusion, all patients will be observed for fever, chills, 
rigors, hypotension, nausea, or other infusion-related AEs. 
All SAEs (as described in Section 7.1.1) that occur after the patient has signed informed consent 
(including the protocol defined follow-up period), regardless of judged relationship to the IP, or 
after the study period, if considered serious and related to IP or to the patient’s participation in 
the study, must be reported to QuintilesIMS within 24 hours of the Investigator’s knowledge of 
the event. The SAE reporting will originate in the electronic data capture (EDC) system and an 
email will be sent to the designated responsible parties defined in the Safety Plan. The paper 
SAE form is in place as a back-up in the rare event that EDC is not accessible to the reporter of 
the SAE and the paper SAE form should be sent to  QLS_Anaptys@quintiles.com. 
The following documents should be submitted to QuintilesIMS Safety: 
• Serious Adverse Event Report Form. 
• The following eCRFs or de-identified source documents: 
o Demographics page(s). 
o Medical history page(s). 
o Adverse event page(s). 
o Concomitant medication page(s). 
o Hospital discharge summary: If the patient is hospitalized because of or during the 
course of an SAE, then a copy of the hospital discharge. 
Following are Investigator responsibilities: 
• Record diagnosis instead of signs and symptoms when available using accepted medical 
terminology. 

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• The events recorded on the safety event report form must be consistent with the 
information entered on the respective CRFs. 
• Include any relevant medical history, concurrent illnesses, and concomitant medicines. 
• Include treatment(s) provided. 
• The Investigator must assess causality at the time of the first SAE notification. 
• The Investigator is responsible for obtaining and forwarding or recording the details of 
the outcome of the SAE on the appropriate eCRF, as well as any other details which may 
be requested by AnaptysBio and/or QuintilesIMS in a timely manner: 
o Hospital records. 
o Medical records. 
o Data clarification. 
o Death certificate/autopsy results. 
o Events should be followed until they are resolved or stabilized, “Resolved with 
sequelae” will require specification of the sequelae. 
o For a fatal or life-threatening SAE, please call QuintilesIMS Safety Group 
(contact information is located on the SAE form), in addition to entering the SAE 
details in the eCRF. 
o The SAEs should continue to be reported for at least 5.5 half-lives of IP following 
last dose. 
o Queries on SAE reports will be generated when there is missing/discrepant 
information, or when there is a need for additional information to completely 
evaluate the report. All supplemental SAE information and or documentation is to 
be recorded on the appropriate eCRF and must be submitted upon request. 
7.1.1.2 
Reporting of Serious Adverse Events to Regulatory Authorities and Investigators 
All SAEs that are considered unexpected and related to the IP will be reported by QuintilesIMS 
as a 15-Day report to the regulatory authorities as applicable and to all participating 
Investigators. The SAEs that are considered unexpected, related to the study and are 
life-threatening or result in death will be reported by QuintilesIMS to the regulatory authorities 
as applicable, and to all participating Investigators as a 7-Day report. QuintilesIMS will ensure 
that all SAEs are reported to the appropriate regulatory authorities. 

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Investigators will be notified by 4uintilesIMS of all SAEs that reTuire prompt submission to 
their Institutional Review Board IRB. Each Investigator must notify the IRB responsible for 
reviewing the study at their site of all -Day or -Day safety reports reTuired by local 
regulations or IRB reTuirements and should provide written documentation of IEC notification 
for each report to 4uintilesIMS. This study will comply with all local regulatory reTuirements 
and adhere to the full reTuirements of IC+ *uideline for Clinical Safety Data Management, 
Definitions and Standards for E[pedited Reporting, Topic E2. 
7.1.1.3 
Follow-Up of Adverse Events 
Any AEs observed from the time of informed consent signed up to the end of the study will be 
followed up to resolution. Resolution means that the patient has returned to a baseline state of 
health or the Investigator does not e[pect any further improvement or worsening of the AE or the 
patient is deemed lost to follow-up. All AEs that occur after the patient completed a clinical 
study should also be reported to AnaptysBio andor 4uintilesIMS within 30 days of the patient¶s 
last visit. 
 
Clinical Laboratory Evaluations 
Blood samples for hematology, clinical chemistry evaluations including serum pregnancy test, 
)S+, and serological assays, will be collected at the visits specified in Table ..  A list of 
specific clinical laboratory evaluations is provided in Table . below: 

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Table 7.1 
Clinical Laboratory Parameters 
Hematology 
Clinical Chemistry 
Virology 
Urinalysis 
Drugs of Abuse 
(Only at 
Screening) 
+ematocrit 
Packed Cell 9olume 
+emoglobin 
Mean Cell 
+aemoglobin 
Mean Cell +emoglobin 
Concentration 
Mean Cell 9olume 
Platelet Count 
Red Blood Cell Count  
:hite Blood Cell 
Count 
Basophils 
Eosinophils 
Monocytes 
Neutrophils 
Lymphocytes 
Immunoglobulins 
IgA, Ig*, IgM, IgE, 
and IgD 
ALT 
Albumin 
ALP 
AST 
Bicarbonate 
Bilirubin Total 
Bilirubin Direct only if 
Total is elevated 
Calcium 
Chloride 
C-Reactive Protein 
Creatinine 
**T 
*lucose 
Potassium 
Phosphate Inorganic 
Protein Total 
Sodium 
Troponin 
Urea 
WOCBP Only - hC* levels 
Postmenopausal woman 
aged over 45 years with at 
least 1 year of amenorrhea 
only - )S+ levels only at 
Screening visit 
+epatitis B 
Surface 
Antigen 
+epatitis C 
Antibody 
+I9 Antibody 
 
 
TB Screening 
4uantiferon 
*old test 
(only at 
Screening 
visit) 
Bilirubin 
Blood 
*lucose 
.etones 
Leukocytes 
Nitrates 
p+ 
Protein 
Specific 
gravity 
Urobilinogen 
 
At discretion 
of 
Investigator 
based on 
urinalysis 
results 
Microbiology 
Urine 
Microscopy 
Amphetamines 
Barbiturates 
Ben]odia]epines 
Cocaine 
MarijuanaCannabis 
Methadone 
Methamphetamine 
Ecstasy 
MorphineOpiates 
Phencyclidine 
Tricyclic 
Antidepressants 
Abbreviations: ALP   alkaline phosphatase ALT   alanine transaminase AST   aspartate aminotransferase 
)S+   follicle stimulating hormone **T   gamma glutamyl transferase hC*   human chorionic gonadotropin 
hormone +I9   human immunodeficiency virus TB   tuberculosis :OCBP   women of childbearing potential. 
The clinical laboratory tests will be reviewed for results of potential clinical significance, based 
on Investigator¶s discretion, at all time points throughout the study. The Investigator will 
evaluate any change in laboratory values. If the Investigator determines a laboratory abnormality 
to be clinically significant, it is considered a laboratory AE however, if the abnormal laboratory 
value is consistent with a current diagnosis, it may be documented accordingly. 
 
Vital Signs, Physical Findings, and Other Safety Assessments 
9ital signs will be measured, and physical e[aminations and EC*s will be performed at the time 
points indicated in the Schedule of Events Table .. 
9ital signs include pulse rate, respiratory rate, body temperature, systolic BP, and diastolic BP. 
The physical e[amination includes evaluation of general appearance, head, eyes, ears, nose, and 
throat, and pulmonary, cardiovascular, gastrointestinal, renalgenitourological, endocrine 
including thyroid, musculoskeletalspinal, lymphatic, and dermatologic systems.  

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During the BPC)C, clinical evaluations using the O)C Symptom Scoring Assessment Tool and 
vital signs will be done before starting the initial placebo challenge, after completion of the final 
placebo challenge, before starting the initial peanut challenge, upon completion of the final 
peanut challenge, and 2 hours after completion of the final peanut challenge. )ull physical 
e[aminations will be performed before starting the initial placebo food challenge and upon 
completion of the final peanut challenge prior to discharge, and more freTuent if deemed 
appropriate by the Investigator on the challenge day. 
A standard 2-lead EC* will be performed by a Tualified physician or nurse. The following 
parameters will be documented: +R, PR interval, 4RS interval, 4T interval, and 4Tc interval. 
The EC* will be reviewed by the Investigator or an authori]ed representative who is 
e[perienced in the evaluation of EC*s and assessed for clinical significance.   
 
Safety Monitoring 
There is no data monitoring committee for this study. 
Timely and complete reporting of safety information assists the Sponsor in identifying any 
untoward medical occurrence, thereby allowing:  protection of safety of study patients 2 a 
greater understanding of the overall safety profile of the IP 3 recognition of dose-related IP 
to[icity  appropriate modification of study protocols  improvements in study design or 
procedures and  adherence to worldwide regulatory reTuirements. 
7.2 
Pharmacodynamics 
)or circulating leukocytes, whole blood 2 mL samples will be taken in 
ethylenediaminetetraacetic acid EDTA 9acutainer 2 mL. Differential :BC counts in whole 
blood will be measured to monitor the circulating leukocyte populations. The sample for 
leukocytes will be obtained as part of the hematology safety laboratory panel at screening, 
Day 2, and Day ET. On Day  and Day , sample for leukocytes will be collected separately 
as there is no safety laboratory assessments on Day  and Day . 
)or circulating cytokines, whole blood samples total . mL will be taken in serum separator 
tube SST. Circulating cytokines measured will include, but may not be limited to, IL-, IL-, 
IL-, IL-3, IL-33, and sST2 see lab manual for detailed collection and processing instructions.  
)or the e[ vivo peanut antigen challenge, whole blood 0 mL samples collected from Stanford 
University patients will be taken in 0 mL SST vacutainer. The whole blood peanut response 
assay e[ vivo will measure cytokine levels released from pathogenic T cells, and should 
include, but may not be limited to, IL-, IL-, IL-, IL-3, and IL-33. 

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The serum and whole blood biomarker time points are presented in Section 18.0 (Appendix 2). 
The actual date and time of the sample collection will be recorded in the patient’s eCRF. The 
details of blood sample collection, sample tube labelling, sample preparation, storage, and 
shipping procedures will be described in a separate laboratory manual. 
The measurement of circulating leukocytes and circulating cytokines will be performed using 
validated assay methods. The measurement of cytokine levels released from pathogenic T cells 
(ex vivo peanut response assay) will be performed using an exploratory assay method developed 
by 
. The analytical methods used to measure these PD endpoints will be 
described in a separate bioanalytical report. 
7.3 
Pharmacokinetics 
Samples (5 mL) of whole blood will be obtained in a 5 mL Vacutainer® SST for the 
determination of ANB020 in human serum. Samples will be collected according to the schedule 
presented in Section 18.0 (Appendix 2). Approximately 40.0 mL of whole blood will be obtained 
from each patient for PK assessments during the study. 
If a patient refuses blood collection for PK analysis, this will not be considered a protocol 
violation as the PK analysis is a secondary objective. 
The actual date and time of dosing and of the blood sample collection will be recorded in the 
patient’s eCRF. The details of blood sample collection, sample tube labelling, sample 
preparation, storage, and shipping procedures will be described in a separate laboratory manual. 
Bioanalysis 
The measurement of the concentrations of ANB020 will be performed using a validated assay 
method. The analytical methods used to measure concentrations of ANB020 will be described in 
a separate bioanalytical report. 
7.4 
Efficacy 
Primary and secondary efficacy endpoints included difference in total cumulative tolerated 
peanut dose during BPCFC between baseline and post-treatment with ANB020 or placebo on 
Day 14 and OFC symptom scores on Day 14.  
Exploratory efficacy endpoints included difference in total cumulative tolerated peanut dose 
during BPCFC between baseline and post-treatment with ANB020 or placebo on Day 45 and 
OFC symptom scores on Day 45. 

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The oral BPCFC will be performed according to the PRACTALL guidelines and Symptoms will 
be monitored using the OFC Symptom Scoring Assessment Tool. Refer section 6.1.1 and 
Appendix II for more details. 
7.5 
Health Outcomes 
Not applicable. 
7.6 
Pharmacogenetics 
Not applicable. 
7.7 
Appropriateness of Measurements 
All safety assessments used in this study are standard, i.e., widely used and generally recognized 
as reliable, accurate, and relevant. 

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8.0 QUALITY CONTROL AND QUALITY ASSURANCE 
According to the Guidelines of Good Clinical Practice (GCP) (CPMP/ICH/135/95), 
QuintilesIMS is responsible for implementing and maintaining quality assurance and quality 
control systems with written SOPs. 
Quality control will be applied to each stage of data handling. 
The following steps will be taken to ensure the accuracy, consistency, completeness, and 
reliability of the data: 
• 
Central laboratories for clinical laboratory parameters. 
• 
Center Qualification visit. 
• 
Center Initiation visit. 
• 
Early center visits post-enrollment. 
• 
Routine center monitoring. 
• 
Ongoing center communication and training. 
• 
Data management quality control checks. 
• 
Continuous data acquisition and cleaning. 
• 
Internal review of data. 
• 
Quality control check of the final clinical study report. 
In addition, AnaptysBio and/or QuintilesIMS Clinical Quality Assurance Department may 
conduct periodic audits of the study processes, including, but not limited to study center, center 
visits, central laboratories, vendors, clinical database, and final clinical study report. When audits 
are conducted, access must be authorized for all study related documents including medical 
history and concomitant medication documentation to authorized AnaptysBio’s representatives 
and regulatory authorities. 
8.1 
Monitoring 
AnaptysBio has engaged the services of a contract research organization, QuintilesIMS, to 
perform all monitoring functions within this clinical study. QuintilesIMS monitors will work in 
accordance with QuintilesIMS SOPs. The monitor will establish and maintain regular contact 
between the Investigator and AnaptysBio. 

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The monitor will evaluate the competence of the study center, informing AnaptysBio about any 
problems relating to facilities, technical equipment, or medical staff. During the study, the 
monitor will check that written informed consent has been obtained from all patients correctly 
and that data are recorded correctly and completely. The monitor is also entitled to compare 
entries in eCRFs with corresponding source data and to inform the Investigator of any errors or 
omissions. The monitor will also assess and control adherence to the protocol and ICH/GCP 
guidelines at the study center. The monitor will arrange for the supply of IP, ensure proper IP 
dispensing/accountability, and appropriate storage conditions are maintained. 
Monitoring visits will be conducted according to all applicable regulatory requirements and 
standards. Regular monitoring visits will be made to each center while patients are enrolled in 
the study.  
During monitoring visits, all entries in the eCRFs will be compared with the original source 
documents (source data verification). For the following and all other items, this check will be 
100%:  
• 
Patient identification number. 
• 
Patient consent obtained. 
• 
Patient eligibility criteria (inclusion and exclusion criteria). 
• 
Efficacy variables. 
• 
Safety variables. 
• 
Medical record of AE. 
8.2 
Data Management/Coding 
Data generated within this clinical study will be handled according to the relevant SOPs of the 
Data Management and Biostatistics departments of QuintilesIMS. 
Electronic data capture will be used for this study, meaning that all eCRF data will be entered in 
electronic forms at the study center. Data collection will be completed by authorized study center 
staff designated by the Investigator. Appropriate training and security measures will be 
completed with the Investigator and all authorized study center staff prior to the study being 
initiated and any data being entered into the system for any study patients. 
All data must be entered in English. The eCRFs should always reflect the latest observations on 
the patients participating in the study. Therefore, the eCRFs are to be completed as soon as 
possible during or after the patient’s visit. To avoid inter-observer variability, every effort should 
be made to ensure that the same individual who made the initial baseline determinations 

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completes all efficacy and safety evaluations. The Investigator must verify that all data entries in 
the eCRFs are accurate and correct. If some assessments are not done, or if certain information is 
not available or not applicable or unknown, the Investigator should indicate this in the eCRF. 
The Investigator will be required to electronically sign off on the clinical data. 
The monitor will review the eCRFs and evaluate them for completeness and consistency. The 
eCRF will be compared with the source documents to ensure that there are no discrepancies 
between critical data. All entries, corrections and alterations are to be made by the responsible 
Investigator or his/her designee. The monitor cannot enter data in the eCRFs. Once clinical data 
of the eCRF have been submitted to the central server, corrections to the data fields will be audit 
trailed, meaning that the reason for change, the name of the person who performed the change, 
together with time and date will be logged. Roles and rights of the center staff responsible for 
entering the clinical data into the eCRF will be determined in advance. If additional corrections 
are needed, the responsible monitor or Data Manager will raise a query in the EDC application. 
The appropriate study center staff will answer queries sent to the Investigator. This will be audit 
trailed by the EDC application meaning that the name of investigational staff, time and date 
stamp are captured. 
The eCRF is essentially considered a data entry form and should not constitute the original (or 
source) medical records unless otherwise specified. Source documents are all documents used by 
the Investigator or hospital that relate to the patient’s medical history, that verify the existence of 
the patient, the inclusion and exclusion criteria and all records covering the patient’s 
participation in the study. They include but are not limited to laboratory notes, ECG results, 
memoranda, pharmacy dispensing records, patient files, etc. 
The Investigator is responsible for maintaining source documents. These will be made available 
for inspection by the study monitor at each monitoring visit. The Investigator must submit a 
completed eCRF for each patient who receives IP, regardless of duration. All supportive 
documentation submitted with the eCRF, such as laboratory or hospital records, should be 
clearly identified with the study and patient number. Any personal information, including patient 
name, should be removed or rendered illegible to preserve individual confidentiality. 
Electronic case report form records will be automatically appended with the identification of the 
creator, by means of their unique User ID. Specified records will be electronically signed by the 
Investigator to document his/her review of the data and acknowledgement that the data are 
accurate. This will be facilitated by means of the Investigator’s unique User ID and password; 
date and time stamps will be added automatically at time of electronic signature. If an entry on 
an eCRF requires change, the correction should be made in accordance with the relevant 
software procedures. All changes will be fully recorded in a protected audit trail, and a reason for 
the change will be required. 

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Adverse events will be coded using current Medical Dictionary for Regulatory Activities 
(MedDRA). Concomitant medications will be coded using World Health Organization Drug 
Dictionary. Concomitant diseases/medical history will be coded using MedDRA. 
8.3 
Quality Assurance Audit 
Study centers, the study database, and study documentation may be subjected to Quality 
Assurance audit during the course of the study by AnaptysBio or QuintilesIMS on behalf of 
AnaptysBio. In addition, inspections may be conducted by regulatory bodies at their discretion. 

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9.0 STATISTICS 
Statistical analyses will be performed by 4uintilesIMS using statistical analysis system SAS, 
SAS Institute, Cary, NC, U.S. 9ersion .2 or higher. 4uintilesIMS SOPs and work instructions 
will be used as the default methodology if not otherwise specified. 
Details of statistical analysis methods will be provided in the statistical analysis plan SAP that 
will be prepared and signed off prior to database lock. Any change to the data analysis methods 
will be documented in the SAP. Any additional analyses, and the justification for making the 
change, will be described in the clinical study report. Additional e[ploratory analyses of the data 
will be conducted as deemed appropriate. 
9.1 
Determination of Sample Size 
As this is the third study with an anti-IL-33 inhibitor, the number of patients to be enrolled is not 
based on statistical power considerations. 
A total of appro[imately 20 patients will be randomi]ed in a 3: ratio to receive ANB020 or 
placebo. 
Analysis populations
Randomized Analysis Set 
All patients who have been allocated to a randomi]ed treatment arm, regardless of whether they 
received the planned treatment or not. 
Full Analysis Set 
All patients who have received ANB020 or placebo and present in study till Day . The full 
analysis set will be used for all efficacy analyses. 
Safety Analysis Set 
All patients who have received ANB020 or placebo. The safety analysis set will be used for all 
safety analyses. 
Pharmacokinetics Analysis Set 
All patients who have received ANB020 and have at least one post-dose serum concentration 
data value available for ANB020 without any events or protocol deviation deemed to affect P. 
assessments. The P. analysis set will be used for all P. analyses. 

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Pharmacodynamics Analysis Set 
All patients who have received at least one dose of ANB020 or placebo and provide at least one 
evaluable post-dose PD measurement without any events or protocol deviation deemed to affect 
PD assessment. The PD analysis set will be used for all PD analyses. 
9.2 
Patient Disposition 
A tabular presentation of the patient disposition will be provided. It will include the number of 
patients screened, enrolled, assigned treatment ANB020, completed till Day, 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 patient. A list of protocol violations will be identified and 
discussed with the InvestigatorAnaptysBio in dry-run to categori]e as major or minor and the 
same will be reported. 
9.3 
Patient Characteristics and Concomitant Medications 
Patient characteristics obtained at screening will be summari]ed for all patients taking ANB020 
and placebo. Summaries will include descriptive statistics for continuous variables sample si]e, 
mean, standard deviation >SD@, median, minimum, and ma[imum and for categorical variables 
sample si]e, freTuency, and percent. Patient characteristics may include, but are not limited to 
age, gender, raceethnicity, height, weight, and BMI. 
Categorical use of concomitant medication will be summari]ed by treatment period and overall. 
All concomitant medications used will be listed.  
9.4 
Safety analyses 
)ollowing are the primary safety endpoints: 
• 
Assessment of AEsSAEs potentially significant and clinically important AEs, SAEs, and 
AEs leading to withdrawal. 
• 
Physical e[aminations. 
• 
9ital signs. 
• 
Clinical safety laboratory tests hematology, biochemistry, and urinalysis. 
• 
Electrocardiograms. 
 
Adverse Events
Adverse events will be coded using the current MedDRA. )or each treatment, numbers of events 
and percentage will be tabulated by preferred term and system organ class. An event that 

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occurred one or more times on treatment will contribute one observation to the numerator and 
denominator comprise all safety patients e[posed to ANB020 or placebo for respective 
treatment. If the intensity or seriousness of the AE changes, the overall intensity or seriousness 
will be the ma[imum intensity or seriousness of the multiple occurrences. The AEs, SAEs, AEs 
leading to treatment discontinuation, and AEs leading to withdrawal of patient will be tabulated 
for each treatment period.  
Summaries over system organ class, preferred term and listings of AEs, AEs leading to death, 
SAEs, potentially significant AEs, clinically important AEs, and AEs that led to discontinuation 
from the study or of the IP will be presented by treatment. Summaries will also be presented by 
relatedness to IP and the severity of the AE. 
 
Vital Signs Measurements, Physical Findings, and Clinical Laboratory 
Evaluations 
Summaries and listings of data for vital signs, hematology, clinical chemistry, and urinalysis 
laboratory tests, EC*s and physical e[amination findings will be presented. Appropriate 
descriptive statistics will be summari]ed for the observed value at each scheduled assessment 
and for the corresponding change from baseline. 
)or hematology and clinical chemistry tests, listings of patient data will also flag up any 
abnormal or out-of-range values. Clinically significant changes in the laboratory test parameters 
will be summari]ed and listed. +ematology and clinical laboratory data will be reported in 
System International units. 
)or EC* variables, the 4T correction factor will be based on both the Ba]ett and )ridericia 
formulae 4TcB and 4Tc). Categorical summaries of absolute 4T, 4TcB and 4Tc) values and 
change from baseline values in 4T, 4TcB and 4Tc) values will be presented by treatment and 
visit. 
Descriptive statistics will be used to present the safety outcomes including, physical e[amination 
results, weight, BMI, vital signs measurements, clinical laboratory test results, and EC* results. 
Change from baseline will also summari]ed for vital signs measurements, clinical laboratory test 
results. 
 
Missing Data 
No imputation will be performed for the missing data. 
9.5
Efficacy analysis
The following are efficacy endpoints. 

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• 
Difference in total cumulative tolerated peanut dose during BPC)C between baseline and 
post-treatment with ANB020 or placebo on Day . 
• 
Difference in total cumulative tolerated peanut dose during BPC)C between baseline and 
post-treatment with ANB020 or placebo BPC)C on Day . 
• 
The O)C score change from baseline on Day  and Day . 
)or the Tuantitative efficacy variables, descriptive statistics including n, mean, minimum, 
ma[imum, and  confidence interval >CI@ will be presented.  
Total cumulative peanut dose tolerated at screening and post ANB020 or placebo administration 
on Day  Day  and Day , if the BPC)C was completed in 2 days and Day  Day  and 
Day , if the BPC)C was completed in 2 days will be summari]ed with descriptive statistics. 
Change from baseline on Day  for tolerated dose and O)C scores will be compared between 
ANB020 and placebo using analysis of covariance ANCO9A with treatment as fi[ed effect 
and baseline results as covariate. Treatment differences will be presented with corresponding 
p-values for the test of no difference and  CI.  
Change from baseline on Day  for tolerated dose and O)C scores will be compared between 
ANB020 and placebo using mi[ed model for repeated measures. The  CI for the difference 
between ANB020 and placebo on Day  will be estimated. This model will include treatment, 
visit, and treatment by visit interaction as fi[ed effect and baseline results as covariate. The data 
collected at baseline, Day , and Day  will be used in this model. 
9.6 
Pharmacokinetic Analyses 
 
Evaluation of Pharmacokinetic Data
The P. parameters will be derived using non-compartmental methods. The actual sampling 
times will be used in the P. parameter calculations. The P. analyses will follow 4uintilesIMS 
SOPs. )urther details of P. analysis will be specified in the SAP. 
:here possible, the following P. parameters will be determined for ANB020 after a single I9 
infusion: 
• Ma[imum observed concentration Cma[ 
• Time to ma[imum observed concentration tma[ 
Additional P. parameters may be determined if deemed appropriate. 
 
Pharmacokinetic Concentration Data Analyses 
A by-patient listing of all concentration-time data for each treatment will be presented. 

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Concentration data of ANB020 will be summari]ed by treatment and nominal time point using 
the number of observations n and number of observations lower limit of Tuantification 
LLO4, arithmetic mean, SD, coefficient of variation C9, minimum, median, and ma[imum. 
*raphs of concentration-time data may be added at the discretion of the P. scientist, as 
appropriate, and will be described in detail in the SAP. 
 
Pharmacokinetic Parameter Data Analyses 
All P. parameters will be summari]ed by treatment using n, arithmetic mean, SD, C9, 
minimum, median, ma[imum, geometric mean *mean, and geometric C9 gC9 defined as 
 
where µs¶ is the SD of the data on a log scale, e[cept that tma[ will be reported with n, minimum, 
median, and ma[imum only.
*raphs of parameters may be added at the discretion of the P. scientist, as appropriate, and will 
be described in detail in the SAP. 
9.7 
Pharmacodynamic Analyses 
Observed and relative change from baseline for circulating cytokines, differential :BC counts 
circulating leukocytes, and cytokine levels released from pathogenic T-cells e[ vivo whole 
blood peanut response assay will be summari]ed with descriptive statistics including  CIs 
for the mean by nominal time point and treatment. *raphical summaries will be generated, as 
appropriate. 
*raphs of PD data may be added, as appropriate, and will be described in detail in the SAP. 
)or secondary and e[ploratory continuous PD endpoints, change from baseline will be evaluated 
where possible. Actual and change in data from baseline will be summari]ed descriptively for 
each treatment. Comparison between ANB020 and placebo will be performed using a 
mi[ed-effect model with treatment, time point of measurement, and treatment by time point 
interaction as fi[ed effects, and baseline results as a covariate. Appropriate correlation matri[ 
will be used. Treatment differences will be presented with corresponding p-values for the test of 
no difference and  CI. *raphical summaries will be generated, as appropriate. Log 
transformations may be applied as appropriate. 
9.8 
Interim Analyses 
No interim analysis is planned for this study. 

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10.0 ETHICS 
10.1 Institutional Review Board 
An IRB should approve the final protocol, including the final version of the Informed Consent 
Form (ICF) and any other written information and/or materials to be provided to the patients. 
The Investigator will provide AnaptysBio or QuintilesIMS with documentation of IRB approval 
of the protocol and informed consent before the study may begin at the study center. The 
Investigator should submit the written approval to AnaptysBio or representative before 
enrolment of any patient into the study. 
AnaptysBio or representative should approve any modifications to the ICF that are needed to 
meet local requirements. 
The Investigator will supply documentation to AnaptysBio or QuintilesIMS of required IRB’s 
annual renewal of the protocol, and any approvals of revisions to the informed consent document 
or amendments to the protocol. 
The Investigator will report promptly to the IRB, any new information that may adversely affect 
the safety of patients or the conduct of the study. Similarly, the Investigator will submit written 
summaries of the study status to the IRB as per IRB’s requirements. Upon completion of the 
study, the Investigator will provide the IRB with a brief report of the outcome of the study, if 
required. 
AnaptysBio or representative will handle the distribution of any of these documents to the 
national regulatory authorities. 
QuintilesIMS or a representative will provide Regulatory Authorities, IRB, and Investigators 
with safety updates/reports according to local requirements, including Suspected Unexpected 
Serious Adverse Reactions, where relevant. 
Each Investigator is responsible for providing the IRB with reports of any serious and 
unexpected adverse drug reactions from any other study conducted with the IP. QuintilesIMS or 
a representative will provide this information to the Investigator so that he/she can meet these 
reporting requirements. 
10.2 Ethical Conduct of the Study 
This study will be conducted and the informed consent will be obtained according to the ethical 
principles stated in the Declaration of Helsinki (2008), the applicable guidelines for GCP, or the 
applicable drug and data protection laws and regulations of the countries where the study will be 
conducted. 

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10.3 Patient Information and Informed Consent 
The ICF will be used to explain the risks and benefits of study participation to the patient in 
simple terms before the patient will be entered into the study. The informed consent form 
contains a statement that the consent is freely given, that the patient is aware of the risks and 
benefits of entering the study, and that the patient is free to withdraw from the study at any time. 
Written consent must be given by the patient and/or legal representative, after the receipt of 
detailed information on the study. 
The Investigator is responsible for ensuring that informed consent is obtained from each patient 
or legal representative and for obtaining the appropriate signatures and dates on the informed 
consent document prior to the performance of any protocol procedures and prior to the 
administration of IP. The Investigator will provide each patient with a copy of the signed and 
dated ICF. 
10.4 Patient Data Protection 
Patient data generated through the study is the property of Sponsor and disclosure to third parties 
is not permitted other than as per Health Insurance Portability and Accountability Act (HIPAA) 
provisions. 
At the patient’s request, medical information may be given to his/her personal physician or other 
appropriate medical personnel responsible for his/her welfare. 
Data generated by this study must be available for inspection on request by the representatives of 
Health Authorities, Sponsor, and IRB, if appropriate. The Investigator must ensure that each 
subject’s anonymity is maintained. 
10.5 Procedures for Premature Termination or Suspension of the Study or 
the Participation of Investigational Site(s) 
In the event that the Sponsor, an IRB, or regulatory authority elects to terminate or suspend the 
study (due to such events as, but not limited to new information becomes available that may 
negatively impact patient safety, IP integrity, withdrawal of IND), a study-specific procedure for 
early termination or suspension will be provided by the Sponsor; the procedure will be followed 
by applicable investigational sites during the course of termination or study suspension. 

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11.0 STUDY ADMINISTRATION 
11.1 ADMINISTRATIVE STRUCTURE 
Table 11.1 
Administrative Structure 
Sponsor 
AnaptysBio Inc. 
10421 Pacific Center Ct Suite 200 
San Diego, CA 92121 
United States 
Drug Safety Monitoring 
QuintilesIMS 
Customer Safety Services 
Global Data & Safety Monitoring 
5927 S. Miami Blvd. 
Morrisville, NC 27560 
United States 
Clinical Study Supply Management 
Investigational Product 
AnaptysBio Inc. 
10421 Pacific Center Ct Suite 200 
San Diego, CA 92121 
United States 
Clinical Study Supply Management Other than 
Investigational product 
QuintilesIMS 
10188 Telesis Court, Suite 400 
San Diego, CA 92121 
United States 
Data Management 
QuintilesIMS 
Data Management 
Etamin Block (Building B3) 
Prestige Technology Park II 
Sarjapur-Marathalli Outer Ring Road 
Bangalore - 560103 
India 
Biostatistics 
QuintilesIMS 
12th Floor, G-Corp Tech Park 
Ghodbunder Road, Kasarwadawli, Thane (West) 
Thane - 400 607 
India 
Study Monitoring 
QuintilesIMS 
10188 Telesis Court, Suite 400 
San Diego, CA 92121 
United States 
Medical Writing 
QuintilesIMS 
Global Medical Writing and Document Publishing 
12th Floor, G-Corp Tech Park 
Ghodbunder Road, Kasarwadawli, Thane (West) 
Thane - 400 607 
India 
Medical Monitoring 
AnaptysBio Inc. 
10421 Pacific Center Ct Suite 200 
San Diego, CA 92121 
United States 
 
11.2 Data Handling and Record Keeping 
The Investigator must maintain essential study documents (protocol and protocol amendments, 
completed eCRFs, signed ICFs, relevant correspondence, and all other supporting 
documentation). The study center should plan on retaining such documents for approximately 
15 years after study completion. The study center should retain such documents until at least 
2 years after the last approval of a marketing application in an ICH region and until there are no 

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pending or contemplated marketing applications in an IC+ region or at least 2 years after the 
formal discontinuation of clinical development of the IP. These documents should be retained for 
a longer period if reTuired by the applicable regulatory reTuirements or the hospital, institution, 
or private practice in which the study is being conducted. Patient identification codes patient 
names and corresponding study numbers will be retained for this same period of time. These 
documents may be transferred to another responsible party, acceptable to AnaptysBio, who 
agrees to abide by the retention policies. :ritten notification of transfer must be submitted to 
AnaptysBio. The Investigator must contact AnaptysBio prior to disposing of any study records. 
11.3 Direct Access to Source Data/Documents 
The Investigator will prepare and maintain adeTuate and accurate source documents to record all 
observations and other pertinent data for each patient randomi]ed into the study. 
The Investigator will allow AnaptysBio, 4uintilesIMS, and authori]ed regulatory authorities to 
have direct access to all documents pertaining to the study, including individual patient medical 
records, as appropriate. Such information must be kept confidential and must have locked 
facilities that allow for this. Patient identification number and not the patient¶s name will be 
recorded on all documents related to the study. 
11.4 Investigator Information 
 
Investigator Obligations 
This study will be conducted in accordance with the IC+ +armoni]ed Tripartite *uideline for 
*CP *CP, , European Legislation and the ethical principles that have their origin in the 
Declaration of +elsinki. 
The Investigator is responsible for ensuring that all study center personnel, including 
Sub-Investigators, adhere to all applicable regulations and guidelines, including local laws and 
regulations, regarding the study, both during and after study completion. The Investigator is 
responsible for informing the IRB of the progress of the study and for obtaining annual IRB 
renewal. The Investigator is responsible for informing the IRB of completion of the study and 
will provide the IRB with a summary of the results of the study. 
 
Protocol Signatures
After reading the protocol, each Investigator will sign the protocol signature page and send a 
copy of the signed page to AnaptysBio or representative Section .0. By signing the protocol, 
the Investigator confirms in writing that heshe has read, understands and will strictly adhere to 
the study protocol and will conduct the study in accordance with IC+ *uidelines for *CP and 

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applicable regulatory reTuirements. The study will not be able to start at any center where the 
Investigator has not signed the protocol. 
 
Publication Policy 
The data generated by this study are confidential information of AnaptysBio. AnaptysBio will 
make the results of the study publicly available. The publication policy with respect to the 
Investigator and study center will be set forth in the Clinical Trial Agreement. 
11.5 Financing and Insurance 
AnaptysBio will provide insurance in accordance with local guidelines and reTuirements as a 
minimum for the patients participating in this study. The terms of the insurance will be kept in 
the study files. 

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12.0 REFERENCES 
1 Pastorelli L, Garg RR, Hoang SB, Spina L, Mattioli B, Scarpa M, et al. Epithelial-derived 
IL-33 and its receptor ST2 are dysregulated in ulcerative colitis and in experimental Th1/Th2 
driven enteritis. Proc. Natl. Acad. of Sci USA. 2010 Apr 27;107(17):8017-8022. 
2 Liew Fy. Il-33: A Janus Cytokine. Ann Rheum Dis. 2012 Apr;71(Suppl 2):I101-I104. 
3 Nabe, T. Interleukin (IL)-33: New Therapeutic Target for Atopic Diseases. J. Pharmacol Sci. 
2014;126:85-91. 
4 Otsu K, Dreskin S. Peanut Allergy: An evolving clinical challenge. Discovery Medicine. 
2011;12(65):319-328. 
5 Bock S, Munoz-Furlong A, Sampson HA. Fatalities due to anaphylactic reactions to foods. 
Journal of Allergy and Clinical Immunology. 2001;107:191-193. 
6 Miller DS, Brown MP, Howley PM, Hayball JD. Type 2 Current and emerging 
immunotherapeutic approaches to treat and prevent peanut allergy. Expert Reviews in Vaccines. 
2012 Dec;11(12):1471-1481. 
7 Du Toit G, Roberts G, Sayre PH, Bahnson HT, Radulovic S, Santos AF et.al. A Randomized 
Trial of Peanut Consumption in Infants at Risk for Peanut Allergy. New England Journal of 
Medicine. 2015;372(9):803-813. 
8 Galand C, Leyva-Castillo JM, Yoon J, Han A, Lee MS, McKenzie AN, et al. IL-33 promotes 
food anaphylaxis in epicutaneously sensitized mice by targeting mast cells. Journal of Allergy 
and Clinical Immunology. 2016 Jun 02; pii: S0091-6749(16) 30369-4 doi: 
10.1016/j.jaci.2016.03.056. [Epub ahead of print]. 
9 Muto T, Fukuoka A, Kabashima K, Ziegler SF, Nakanishi K, Matsushita K, Yoshimoto T. The 
role of basophils and proallergic cytokines, TSLP and IL-33, in cutaneously sensitized food 
allergy. International immunology. 2014 Oct;26(10):539-49. 
10 Ohno T, Morita H, Arae K, Matsumoto K, Nakae S. Interleukin-33 in allergy. European 
Journal of Allergy and Clinical Immunology. 2012 Oct;67(10):1203-1214. 
11 Sampson HA, Aceves S, Bock SA, James J, Jones S, Lang D, et al. Journal of Allergy and 
Clinical Immunology. 2014 Nov;134(5):1016-1025. 
12 Robert A wood. Journal of Allergy and Clinical Immunology. 2016 Apr;137(4):973-982. 
                                               

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13 Guidance for industry. Exposure-Response relationships-Study Design, Data Analysis, and 
Regulatory Applications. U.S. Department of Health and Human Services Food and Drug 
Administration Guidance Document 2003 Apr; Section III A:Page 3. 
14 GINA symptom control available from: www.ginasthma.org. 
15 Sampson HA, Gerth Van Wijk R, Bindslev-Jensen C, Sicherer S, Teuber SS, Burks AW, et al. 
2012 Dec;130(6):1260-0174. 
16 Nowak-Wegrzyn A, Assa’ad AH, Bahna SL, Bock SA, Sicherer SH, Teuber SS. Adverse 
Reactions to Food Committee of the American Academy of Allergy, Asthma & Immunology. 
Journal of Allergy and Clinical Immunology; 2009 Jun;123(6):376. 
17 Lieberman P, Nicklas RA, Randolph C, Oppenheimer J, Bernstein D, Bernstein J, et al. Annals 
of Allergy Asthma, and Immunology. 2015;115:341-384. 
18 Bernstein IL, Li JT, Bernstein DI, Hamilton R, Spector SL, Tan R, et.al. Annals of Allergy 
Asthma, and Immunology. 2008 Mar;100(3). 

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14.0 APPENDIX II 
Oral Food Challenge Symptom Scoring Assessment Tool 
Category 
Grade 
Symptoms 
Skin  
 
 
           Rash  
Grade 0:  
Sign or symptom not observed  
 
Grade 1:  
Few areas of faint erythema  
 
Grade 2:  
Areas of erythema, macular and raised rash  
 
Grade 3: 
Generalized marked erythema (>50%); extensive 
raised lesion (>25%); vesiculation and/or 
piloerections 
           Pruritus  
Grade 0:  
Sign or symptom not observed  
 
Grade 1:  
Occasional scratching  
 
Grade 2:  
Scratching continuously for >2 minutes at a time  
 
Grade 3:  
Hard continuous scratching leading to 
excoriations  
           Urticaria  
Grade 0:  
Sign or symptom not observed  
 
Grade 1:  
<3 Hives  
 
Grade 2:  
3 to <10 Hives  
 
Grade 3:  
Generalized involvement  
           Angioedema  
Grade 0:  
Sign or symptom not observed  
 
Grade 1:  
One site of angioedema  
 
Grade 2:  
Two or more sites of angioedema  
 
Grade 3:  
Generalized involvement, including airway 
involvement 
Nasal  
 
 
          Sneezing  
Grade 0:  
Sign or symptom not observed  
 
Grade 1:  
Rare bursts of sneezing  
 
Grade 2:  
<10 bursts of sneezing  

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Category 
Grade 
Symptoms 
 
Grade 3:  
Continuous rubbing of nose and/or eyes; 
periocular swelling and/or long bursts of 
sneezing  
      Nasal itching  
Grade 0:  
Sign or symptom not observed  
 
Grade 1:  
Mild itching  
 
Grade 2:  
Intermittent rubbing of nose or eyes  
 
Grade 3:  
Continuous rubbing of nose and/or eyes; 
periocular swelling and/or long bursts of 
sneezing 
      Nasal congestion  
Grade 0:  
Sign or symptom not observed  
 
Grade 1:  
Some hindrance to breathing  
 
 Grade 2:  
Nostrils feel blocked, breathes through mouth 
most of the time 
 
Grade 3:  
Nostrils occluded  
      Rhinorrhea  
Grade 0:  
Sign or symptom not observed  
 
Grade 1:  
Occasional sniffing  
 
Grade 2:  
Frequent sniffing, requires tissues  
 
Grade 3:  
Nose runs freely despite sniffing and tissues  
    Airway obstruction  
Grade 0:  
Sign or symptom not observed  
 
Grade 1:  
Voice change mild  
 
Grade 2:  
Voice change moderate  
 
Grade 3:  
Voice change severe or  hoarseness  or stridor   
Chest  
 
 
     Wheezing  
Grade 0:  
Sign or symptom not observed  
 
Grade 1:  
Expiratory wheezing to auscultation or 15% 
decrease from highest FEV1 value observed on 
study or FEV1 ≤65% 
 
Grade 2:  
Dyspnea, inspiratory, and expiratory wheezing  

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Category 
Grade 
Symptoms 
 
Grade 3:  
Dyspnea, use of accessory muscles, audible 
wheezing 
Abdomen  
 
 
     Nausea  
Grade 0:  
Sign or symptom not observed  
 
Grade 1:  
Mild complaint of nausea  
 
Grade 2:  
Frequent complaint of nausea  
 
Grade 3:  
Nausea causing notable distress  
   Abdominal pain  
Grade 0:  
Sign or symptom not observed  
 
    Grade 1:  
Complaint of abdominal pain  
 
Grade 2:  
Frequent complaints of abdominal pain, 
decreased activity   
 
Grade 3:  
In bed, crying, or notably distressed  
     Emesis  
Grade 0:  
Sign or symptom not observed  
 
Grade 1:  
1 Episode of emesis  
 
Grade 2:  
2-3 Episodes of emesis or 1 of emesis and 1 of 
diarrhea 
 
Grade 3:  
>3 Episodes of emesis or ≥2 of emesis and ≥2 of 
diarrhea 
     Diarrhea  
Grade 0:  
Sign or symptom not observed  
 
Grade 1:  
1 Episode of diarrhea  
 
Grade 2:  
2–3 Episodes of diarrhea or 1 of emesis and 1 of 
diarrhea 
 
Grade 3:  
>3 Episodes of diarrhea or ≥2 of emesis and ≥2 
of diarrhea 
Grade 1 = mild; Grade 2 = moderate, Grade 3 = severe 

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15.0 APPENDIX III 
Guidelines for Discontinuation of Medications that might interfere with the Interpretation 
of Oral Food Challenge 
Medication 
Last Dose before Oral Food Challenge 
Oral antihistamines 
3-10 days 
Cetirizine 
5-7 days 
Diphenhydramine 
3 days 
Fexofenadine 
3 days 
Hydroxyzine 
7-10 days 
Loratadine 
7 days 
Antihistamine nose spray 
12 hours 
Oral H2 receptor antagonist 
12 hours 
Antidepressants 
3 days-3 weeks, drug-dependent and 
dose-dependent 
Oral/intramuscular/intravenous steroids 
3 days-2 weeks 
Leukotriene antagonist 
24 hours 
Short-acting bronchodilator (albuterol, 
metaproterenol) 
8 hours 
Short-acting bronchodilator (terbutaline, 
isoproterenol) 
24 hours 
Long-acting bronchodilator (salmeterol, 
formoterol) 
8 hours 
Inhaled cromolyn sodium 
48 hours 
Nedocromil sodium 
12 hours 
Theophylline (liquid) 
24 hours 
Theophylline long-acting 
48 hours 
Ipratropium bromide (inhaled/intranasal) 
4-12 hours depending on formulation and 
dosing 
Oral/intranasal α-adrenergic agents 
Interval 
Oral β-agonist 
12 hours 
Oral long-acting β2-agonist  
24 hours 
Drugs that may be continued 
 
Antihistamine eye drops 
 
Inhaled/intranasal corticosteroids 
 
Topical steroids 
 
Topical immunosuppressive preparations: 
pimecrolimus, tacrolimus 
 
 

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16.0 APPENDIX IV 
Standard Anaphylaxis Treatment Plan 
Treatment of Anaphylaxis in the Physician’s office 
Immediate Measures 
1 
Allergen 
Remove the inciting allergen, if possible 
2 
Airway 
Assess airway, breathing, circulation, and orientation; if 
needed, support the airway using the least invasive but 
effective method (e.g., bag-valve-mask) 
3 
Cardiopulmonary 
resuscitation 
Start chest compressions (100/min) if cardiovascular 
arrest occurs at any time 
4 
Epinephrine 
intramuscular 
Inject epinephrine 0.3-0.5 mg (0.01 mg/kg for children) 
intramuscularly in the vastus lateralis 
(lateral thigh) 
5 
Get help 
Summon appropriate assistance in office 
6 
Position 
Place adults and adolescents in recumbent position; place 
young children in position of comfort; place pregnant 
patient on left side 
7 
Oxygen 
Give 8-10 L/min through facemask or up to 100% 
oxygen as needed; monitor by pulse oximetry if 
available 
7 
Epinephrine 
intramuscular 
Repeat intramuscular epinephrine every 5-15 min for up 
to 3 injections if the patient is not responding 
6 
EMS 
Activate Emergency Medical Service (call 911 or local 
rescue squad) if no immediate response to first dose of 
intramuscular epinephrine or if anaphylaxis is moderate 
to severe (Grade ≥2 on World Allergy Organization 
grading scale) 
7 
Intravenous fluids 
Establish intravenous line for venous access and fluid 
replacement; keep open with 0.9 normal saline, push 
fluids for hypotension or failure to respond to 
epinephrine using 5-10 mg/kg as quickly as possible and 
up to 30 mL/kg in first hour for children and 1-2 L for 
adults 
Additional Measures 
8 
Albuterol 
Consider administration of 2.5-5 mg of nebulized 
albuterol in 3 mL of saline for lower airway obstruction; 
repeat as necessary every 15 min 
9 
Glucagon 
Patients on β-blockers who are not responding to 
epinephrine should be given 1-5 mg of glucagon 
intravenously slowly over 5 min because rapid 
administration of glucagon can induce vomiting 

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10 
Epinephrine infusion 
For patients with inadequate response to intramuscular 
epinephrine and intravenous saline, give epinephrine by 
continuous infusion by micro-drip in office setting 
(infusion pump in hospital setting); add 1 mg (1 mL of 
1:1,000) of epinephrine to 1,000 mL of 0.9 normal 
saline; start infusion at 2 µg/min (2 mL/min=120 mL/h) 
and increase up to 10 µg/min (10 mL/min=600 mL/h); 
titrate dose continuously according to blood pressure, 
cardiac rate and function, and oxygenation 
11 
Intraosseous access 
If intravenous access is not readily available in patients 
experiencing refractory anaphylaxis, obtain intraosseous 
access for administration of intravenous fluids and 
epinephrine infusion 
Refractory anaphylaxis 
12 
Advanced airway 
management 
Use supraglottic airway, endotracheal intubation, or 
cricothyroidotomy for marked stridor, severe laryngeal 
edema, or when ventilation using the bag-valve-mask is 
inadequate and Emergency Medical Service has not 
arrived 
13 
Vasopressors 
Consider administration of dopamine (in addition to 
epinephrine infusion) if patient is unresponsive to above 
treatment; this will likely be in the hospital setting where 
cardiac monitoring is available 
Optional treatment (efficacy has not been established) 
14 
H1 antihistamine 
Consider giving 25-50 mg of diphenhydramine 
intravenously for adults and 1 mg/kg (maximum 50 mg) 
for children; use 10 mg of cetirizine if an oral 
antihistamine is administered; once there is full recovery, 
there is no evidence that this medication needs to be 
continued 
15 
Corticosteroids 
Administer 1-2 mg/kg up to 125 mg per dose, 
intravenously or orally, of methylprednisolone or an 
equivalent formulation; once there is full recovery, there 
is no evidence that this medication needs to be continued 
Observation and monitoring 
16 
Observation in 
hospital 
Transport to emergency department by EMS for further 
treatment and observation for 8 hours 
17 
Observation in office 
Observe in office until full recovery +additional 30-60 
min for all patients who are not candidates for 
Emergency Medical Service transport to emergency 
department 
Discharge management 
18 
Education 
Educate patient and family on how to recognize and how 
to treat anaphylaxis 

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19 
Auto-injectable 
epinephrine 
Prescribe 2 doses of auto-injectable epinephrine for 
patients who have experienced an anaphylactic reaction 
and for those at risk for severe anaphylaxis; train patient, 
patient provider, and family on how to use the auto-
injector 
20 
Anaphylaxis action 
plan 
Provide patients with an action plan instructing them on 
how and when to administer epinephrine 
EMS = Emergency Medical Service 

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17.0 APPENDIX 1: SIGNATURE OF INVESTIGATOR 
PROTOCOL TITLE: Placebo-Controlled Proof of Concept Study to Investigate ANB020 
Activity in Adult Patients with Peanut Allergy 
PROTOCOL NO: 
ANB020-003 
This protocol is a confidential communication of AnaptysBio. I confirm that I have read this 
protocol, I understand it, and I will work according to this protocol. I will also work consistently 
with the ethical principles that have their origin in the Declaration of Helsinki and that are 
consistent with good clinical practices and the applicable laws and regulations. Acceptance of 
this document constitutes my agreement that no unpublished information contained herein will 
be published or disclosed without prior written approval from AnaptysBio. 
Instructions to the Investigator: Please SIGN and DATE this signature page. PRINT your name, title, and the 
name of the center in which the study will be conducted. Return the signed copy to QuintilesIMS. 
 
I have read this protocol in its entirety and agree to conduct the study accordingly: 
 
Signature of Investigator:      
__________________________            Date:  ________ 
Printed Name:                                ___________________________ 
Investigator Title:                           ___________________________ 
 
Name/Address of Center:               ___________________________ 
 
___________________________ 
 
___________________________ 
 

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b 
If the Investigator decides to complete the BPCFC in 2 days, the blood samples scheduled on Day 15 will be collected 
on Day 16.  If the Investigator decides to utilize the +4 day visit window for Day 14 and separate the two challenges to 
occur over two consecutive days, the blood samples will be collected the day after the last BPCFC challenge. 
c 
If the patient discontinues from study before Day 45 and returns to site for early termination (ET) visit, the 
PK sample will be collected at ET visit. 
d 
If necessary, the sample for ex vivo peanut challenge assay can be collected on Day 1 (prior to IP 
administration) instead of the screening visit.  

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19.0 APPENDIX 3: SUMMARY OF CHANGES 
Protocol ANB020-003: Amendment 5, 01 DEC 2017 
Replaces: Amendment 4, 06 OCT 2017 
1. Study Synopsis- Pages 3, 4, 5: 
a. Description of Change: Changing study duration to 66 days and screening period 
to 21 days 
Purpose of Change: Allow time and flexibility for screening procedures 
Description of Change: Add “Informed consent must be obtained prior to 
participation in the study.” 
Purpose of Change: To clarify the Informed consent can be obtained prior to the 
screening visit. 
b. Description of Change: Remove the requirement of the Day 45 BPCFC if an 
objective reaction occurred at Day 14/15. 
Purpose of Change: For patient safety, not requiring the Day 45 BPCFC if a 
reaction was observed at the Day 14/15 BPCFC.  The Investigator may decide to 
conduct the BPCFC per his/her discretion. 
c. Description of Change: Changed “either peanut or placebo” to placebo.   
Purpose of Change: To clarify that subjects would receive placebo challenge first. 
2. Summary of Study Design - Pages 21, 22: 
a. Description of Change: Add “Informed consent must be obtained prior to 
participation in the study.” 
Purpose of Change: To clarify the Informed consent can be obtained prior to the 
screening visit. 
b. Description of Change: Remove the requirement of the Day 45 BPCFC if an 
objective reaction occurred at Day 14/15. 
Purpose of Change: For patient safety, not requiring the Day 45 BPCFC if a 
reaction was observed at the Day 14/15 BPCFC.  The investigator may decide to 
conduct the BPCFC per his/her discretion. 
c. Description of Change: Changed “either peanut or placebo” to placebo.   
Purpose of Change: To clarify that subjects would receive placebo challenge first. 
3. Figure 4.1: Schematic of Study Design for protocol ANB020-003 –Page 24:   
a. Description of Change: Changing screening period to 21 days 
Purpose of Change: Allow time and flexibility for screening procedures 

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b. Description of Change: Remove the requirement of the Day 45 BPCFC if an 
objective reaction occurred at Day 14/15. 
Purpose of Change: For patient safety, not requiring the Day 45 BPCFC if a 
reaction was observed at the Day 14/15 BPCFC.  The investigator may decide to 
conduct the BPCFC per his/her discretion. 
c. Description of Change: Changed “either peanut or placebo” to placebo.   
Purpose of Change: To clarify that subjects would receive placebo challenge first. 
4. Table 4.1: Schedule of Events – Page 25, 26:  
a. Description of Change: Changing screening period to 21 days 
Purpose of Change: Allow time and flexibility for screening procedures 
b. Description of Change: Add “Informed consent must be obtained prior to 
participation in the study.” 
Purpose of Change: To clarify the Informed consent can be obtained prior to the 
screening visit. 
c. Description of Change: Remove the requirement of the Day 45 BPCFC if an 
objective reaction occurred at Day 14/15. 
Purpose of Change: For patient safety, not requiring the Day 45 BPCFC if a 
reaction was observed at the Day 14/15 BPCFC.  The investigator may decide to 
conduct the BPCFC per his/her discretion. 
5. Section 6.0:  Study Procedures – Page 37:  
a. Description of Change: Change the visit window to + 4 days for Day 14/15. 
Purpose of Change: To provide flexibility to accommodate subject schedules. 
 
6. Section 6.1: Screening – Page 37:   
a. Description of Change: Add “Informed consent must be obtained prior to 
participation in the study.” 
Purpose of Change: To clarify the Informed consent can be obtained prior to the 
screening visit. 
7. Section 6.2.3: Day 2 to Day 15 – Page 40:  
a. Description of Change: Changed “either peanut or placebo” to placebo.   
Purpose of Change: To clarify that subjects would receive placebo challenge first. 
 
8. Section 6.2.5: End of Study – Page 41:  
a. Description of Change: Remove the requirement of the Day 45 BPCFC if an 
objective reaction occurred at Day 14/15. 

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Purpose of Change: For patient safety, not requiring the Day 45 BPCFC if a 
reaction was observed at the Day 14/15 BPCFC.  The investigator may decide to 
conduct the BPCFC per his/her discretion. 
 
9. Appendix 2: Pharmacokinetic/Whole Blood Serum) Biomarker Time Points– Page 77, 
78:  
a. Description of Change: Change window from ±16 hours to +112 hours 
Purpose of Change: To provide flexibility to accommodate subject schedules and 
to be consistent with the visit window.  This timing accommodates the +4 day 
window and +16 hours if the food challenges are separated into two days. 
b. Description of Change: Add “If the Investigator decides to utilize the +4 day visit 
window for Day 14 and separate the two challenges to occur over two consecutive 
days, the blood samples will be collected the day after the last BPCFC challenge.” 
Purpose of Change: To clarify the expected timing of the blood sample collection 
if the food challenges are separated into two consecutive days and the +4 day visit 
window is implemented for the Day 14 visit.  
 
 
Protocol ANB020-003: Amendment 4, 06 OCT 2017 
Replaces: Amendment 3, 30 JUN 2017 
 
10. Study Synopsis- Pages 3, 4, 5: 
a. Description of Change: Remove investigator name. 
Purpose of Change: Allow for the addition of new sites. 
b. Description of Change: Remove Study Center Details:  Remove Stanford’s 
Address and indicate conducted at up to 3 study centers in US. 
 
Purpose of Change: Allow for the addition of new sites. 
c. Description of Change: Exploratory Endpoints, Methodology, Summary, and 
Exploratory Pharmacodynamic Endpoints: Specify ex-vivo peanut challenge is 
only to be collected and assessed for those patients treated at Stanford University. 
Purpose of Change: AnaptysBio determined that additional, non-Stanford study 
sites (i.e., “new sites”), will not collect blood samples for the ex-vivo peanut 
challenge assay as it was developed specific to the local laboratory as an 
exploratory endpoint. 
11. Section 3.3:  Exploratory Objectives – Page 20:   
a. Description of Change: Add “Stanford University Only”. 

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Purpose of Change: To clarify the ex vivo peanut antigen challenge is for 
Stanford University only. New Sites will not conduct ex vivo peanut antigen 
challenge. 
 
12. Section 4.1: Summary of Study Design – Page 2, 21:  
a. Description of Change: Add “Stanford University patients”.  
Purpose of Change: To clarify the ex vivo peanut antigen challenge is for 
Stanford University only. New Sites will not collect/evaluate immune response to 
peanut upon ex vivo peanut antigen. 
b. Description of Change: Add “Stanford University patients” at screening. 
Purpose of Change: To clarify the ex vivo peanut antigen challenge is for 
Stanford University only. New Sites will not collect/evaluate immune response to 
peanut upon ex vivo peanut antigen. 
c. Description of Change: Add “Stanford University patients” on Day 2 and 5. 
Purpose of Change: To clarify the ex vivo peanut antigen challenge is for 
Stanford University only. New Sites will not collect/evaluate immune response to 
peanut upon ex vivo peanut antigen. 
13. Figure 4.1: Schematic of Study Design for protocol ANB020-003 –Page 24:   
a. Description of Change: Add “Stanford University patients” at screening and on 
Day 2 and 5. 
Purpose of Change: To clarify the ex vivo peanut antigen challenge is for 
Stanford University only. New Sites will not collect/evaluate immune response to 
peanut upon ex vivo peanut antigen. 
14. Table 4.1: Schedule of Events – Page 25, 26:  
a. Description of Change: Ex vivo Peanut challenge Assay will specify “Stanford 
University Only” and footnote will be updated accordingly. 
Purpose of Change: To clarify the ex vivo peanut antigen challenge is for 
Stanford University only. New Sites will not collect/evaluate immune response to 
peanut upon ex vivo peanut antigen. 
 
15. Section 6.0:  Study Procedures – Page 37:  
a. Description of Change: Add “collected from Stanford University patients”  
Purpose of Change: To specify that screening ex vivo blood draw window only 
applies to Stanford University. New Sites will not collect/evaluate immune 
response to peanut upon ex vivo peanut antigen. 
 
16. Section 6.1: Screening – Page 37:   

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a. Description of Change: Specify screening ex-vivo blood draw does not apply to 
New Sites. 
Purpose of Change: New Sites will not collect/evaluate immune response to 
peanut upon ex vivo peanut antigen. 
 
17. Section 6.2.1: Blood Volume – Page 39:  
a. Description of Change: Update total blood draw volume for Stanford patients 
(177 mL) and non-Stanford patients (147 mL). 
Purpose of Change: To indicate decreased total blood draw volume for patients at 
non-Stanford sites.  
 
18. Table 6.1: Blood Volume Sampling During Each Visit – Page 40:   
a. Description of Change: Separate Stanford and new sites total blood volume. New 
Sites will have decreased volume of blood drawn (-10mL) at Screening, Day 2, 
and Day 5. 
Purpose of Change: To indicate decreased total blood draw volume for patients at 
non-Stanford sites.  
Visits 
Screening 
Day 1 
Predose 
Day 1 
Predose 
(PK) 
Day 1 
(0.5H) 
(PK) 
Day 1 
(EOI) 
(PK) 
Day 1 
(EOI 3H) 
(PK) 
Day 2 
Day 5 
Day 14 
Day 
15/16 
Day 45 
Stanford 
Univ. Only 
Total blood 
volume 
sampled 
during each 
visit (mLs) 
up to 41 
(31-41)a 
up to 22 
(12-22)a 
5 
5 
5 
5 
34 
25.5 
12 
15.5 
17 
Total blood 
volume 
sampled 
during each 
visit (mLs) 
31 
12 
5 
5 
5 
5 
24 
15.5 
12 
15.5 
17 
 
19. Section 6.2.2: Day 1 (Randomization) – Page 40:   
a. Description of Change: Add “collected from Stanford University patients”.  
Purpose of Change: To specify that screening ex vivo blood draw window only 
applies to Stanford University. New Sites will not collect/evaluate immune 
response to peanut upon ex vivo peanut antigen. 
20. Section 7.2: Pharmacodynamics – Page 49:   
a. Description of Change: Addition of “collected from Stanford University patients”. 
Purpose of Change: All reference to the ex vivo peanut antigen challenge, whole 
blood samples and cytokine levels will only apply to samples collected from 
patients treated at Stanford University.  

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21. Appendix 2: Pharmacokinetic/Whole Blood Serum) Biomarker Time Points– Page 77:  
a. Description of Change: Add “Stanford University Only” to the Sample Time 
Point for biomarker whole blood collection for Ex vivo Peanut Challenge 
Purpose of Change: To clarify the ex vivo peanut antigen challenge is for 
Stanford University only. New Sites will not conduct ex vivo peanut antigen 
challenge. 
Protocol ANB020-003: Amendment 3, 30 JUN 2017 
Replaces: Amendment 2, 18 MAY 2017 
1. Inclusion Criteria 
a. Description of change:  Increased maximum BMI from 32 to 36 kg/m2 
Purpose of change:  Updated BMI to reflect acceptable weight range of patient 
population. 
2. Exclusion Criteria 
a. Description of change:  Specified immunotherapy to allergens (excluding peanut) 
is only excluded during build-up phase of treatment (before reaching maintenance 
dosing). 
Purpose of change:  To allow treatment of typical allergens that will not affect 
study data or patient safety. 
3. Section 5.8.1 (Excluded Medications) 
a. Description of change: Updated timelines for excluded medication use to reflect 
the changes in the exclusion criteria.  
Purpose of change: To accurately reflect exclusion criteria allowing treatment of 
typical allergens that will not affect study data or patient safety 
Protocol ANB020-003: Amendment 2, 18 MAY 2017 
Replaces: Amendment 1, 01 DEC 2016 
1. Synopsis 
a. Description of Change: Added oral blind placebo-controlled food challenge 
(BPCFC) on Day 45 (End of Study [EOS] visit). 
Purpose for Change: The Day 45 oral BPCFC was added to ascertain duration of 
ANB020 response in peanut allergy. 
b. Description of Change: Updated primary and secondary objectives to specify 
Day 14. 
Purpose for Change: To differentiate primary and secondary objectives from the 
new exploratory objectives. 
c. Description of Change: Added new exploratory objectives. 

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Purpose for Change: To reflect the changes in the study design (to reflect addition 
of BPCFC on Day 45). 
d. Description of Change: Updated methodology to include details about BPCFC on 
Day 45 (EOS visit) and corresponding procedures. 
Purpose for Change: To reflect the changes in the study design. 
e. Description of Change: Added text regarding other EOS visit procedures to 
perform on Day 45. 
Purpose for Change: To provide clarity for performing other EOS visit procedures 
on Day 45. 
f. Updated primary and secondary efficacy endpoints to specify Day 14. 
Purpose for Change: To differentiate primary and secondary efficacy endpoints 
from the new exploratory efficacy endpoints. 
g. Description of Change: Added exploratory efficacy endpoints to assess on 
Day 45. 
Purpose for Change: To reflect the changes in the study design (to reflect addition 
of BPCFC on Day 45). 
h. Description of Change: Updated statistical analysis methods for primary and 
secondary endpoints and added statistical analysis methods for new exploratory 
endpoints. 
Purpose for Change: To reflect the appropriate statistical analysis methods for 
endpoints based on the changes in the study design. 
 
2. Section 3.0 (Study Objectives)  
a. Description of Change: Updated primary and secondary objectives to specify 
Day 14. 
Purpose for Change: To differentiate primary and secondary objectives from the 
new exploratory objectives. 
b. Description of Change: Added new exploratory objectives. 
Purpose for Change: To reflect the changes in the study design (to reflect addition 
of BPCFC on Day 45). 
 
3. Section 4.1 (Summary of Study Design)  
a. Description of Change: Updated study design to include details about BPCFC on 
Day 45 (EOS visit) and corresponding procedures. 
Purpose for Change: To reflect the changes in the study design (to reflect addition 
of BPCFC on Day 45). 
b. Description of Change: Added text regarding other EOS visit procedures to 
perform on Day 45. 

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Purpose for Change: To provide clarity for performing other EOS visit procedures 
on Day 45. 
 
4. Figure 4.1 
a. Description of Change: Added BPCFC and other assessments on Day 45 (EOS 
visit) and added additional Day 46 visit to complete the BPCFC if the Investigator 
decides to split the food challenges into 2 days. 
Purpose for Change: To reflect the changes in study design (to reflect addition of 
BPCFC on Day 45). 
b. Description of Change: Added footnotes regarding details and assessments related 
to BPCFC as well as other assessments on Day 45 and Day 46. 
Purpose for Change: To provide clarity for assessments related to BPCFC as well 
as other assessments on Day 45 and Day 46. 
 
5. Table 4.1 (Schedule of Events)  
a. Description of Change: Added BPCFC on Day 45 and corresponding procedures 
with appropriate footnotes. 
Purpose for Change: To reflect the changes in study design. 
b. Description of Change: Added Day 46 visit to complete the BPCFC and 
corresponding procedures if the Investigator decides to split the food challenges 
into 2 days. 
Purpose for Change: To reflect the changes in study design. 
c. Description of Change: Updated footnote ‘e’ to increase the window period for 
collecting the blood sample for ex vivo peanut challenge assay. 
Purpose for Change: Increased collection window allows flexibility for 
laboratories to process the blood samples. 
d. Description of Change: Modified footnote ‘i’ to clarify spirometry or peak flow 
collection language. 
Purpose for Change: To provide clarity for spirometry or peak flow collection 
time points for patients with a history of asthma. 
e. Description of Change: Added footnotes ‘m’ and ‘n’ to provide instructions for 
BPCFC procedures as well as other procedures on Day 45 and Day 46 visit. 
Purpose for Change: To provide guidance regarding study procedures on Day 45 
and 46 if the BPCFC is split into 2 days. 
f. Description of Change: Added footnote ‘o’ to provide instruction for early 
termination BPCFC and updated early termination (ET) visit header to include 
reference to footnote ‘o’. 

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Purpose for Change: To provide guidance on when to conduct the BPCFC if a 
patient terminates from the study before completing all study visits. 
6. Section 4.2 (Discussion of Study Design) 
a. Description of Change: Added Day 45 BPCFC in the study design. 
Purpose for Change: To reflect the changes in the study design. 
 
7. Section 4.3.2 (Exclusion Criteria) 
Description of Change: 
a. Updated exclusion criteria: Decreased restriction for use of systemic 
corticosteroids, nonsteroidal, immunosuppressant, or immunomodulating drugs 
treatments from 8 weeks before screening to 2 weeks before screening. 
b. Updated exclusion criteria: Decreased restriction for use of beta blockers, 
angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, or 
calcium channel blockers from 4 weeks before screening to 2 weeks before 
screening. 
c. Updated exclusion criteria: Decreased restriction for use of biologics such as 
omalizumab or any other unconventional allergen immunotherapy from 12 
months before screening to 6 months before screening. 
Purpose for Change: The timelines for prior use of treatments were determined to be 
excessive and review of half-lives allow for decreased timeframe. 
 
8. Section 4.3.2 (Exclusion Criteria) 
Description of Change: Modified exclusion criteria to allow inclusion of asthma patients 
requiring Global Initiative for Asthma Assessment (GINA) treatment Step 3.   
Purpose for Change: Asthma is commonly found in patients with peanut allergy and 
affects much of the study population.   
 
9. Section 5.7 (Blinding) 
Description of Change: Updated headings in section 5.7 to include unblinding 
information and provide details for unblinding procedures. 
Purpose for Change: To provide unblinding information and instruction should 
unblinding be necessary during the study. 
 
10. Section 5.8.1 (Excluded Medications) 
Description of Change: Updated timelines for excluded medication use to reflect the 
changes in the exclusion criteria.  

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a. Decreased restriction for use of systemic corticosteroids, nonsteroidal, 
immunosuppressant, or immunomodulating drugs treatments from 8 weeks before 
screening to 2 weeks before screening. 
b. Decreased restriction for use of beta blockers, angiotensin-converting enzyme 
inhibitors, angiotensin-receptor blockers, or calcium channel blockers from          
4 weeks before screening to 2 weeks before screening. 
c. Decreased restriction for use of biologics such as omalizumab or any other 
unconventional allergen immunotherapy from 12 months before screening to      
6-months before screening. 
Purpose for Change: To reflect the changes regarding prior medication use in the 
exclusion criteria. 
 
11. Section 6.0 (Study Procedures)  
a. Description of Change: Added a +1 day visit window for Day 14 visit and 
clarified the existing study window periods. 
Purpose for Change: To provide scheduling flexibility and to provide clarity for 
existing study windows. 
b. Description of Change: Added text regarding increased window period for 
collecting the blood sample for ex vivo peanut challenge assay. 
Purpose for Change: Increased collection window allows flexibility for 
laboratories to process blood samples. 
 
12. Section 6.1.1 (Study Procedures: Oral Blind Placebo-Controlled Food Challenge) 
a. Description of Change: Added text regarding BPCFC to perform on Day 45. 
Purpose for Change: To reflect the changes in the study design. 
b. Description of Change: Modified text regarding administration of BPCFC. 
Purpose for Change: To allow trained study staff to administer OFC. 
c. Description of Change: Added “objective” to assessment of reaction related to the 
OCF Symptom Scoring Assessment. 
Purpose for Change: To ensure accurate dose is recorded on the OFC Symptom 
Scoring Assessment Tool. 
d. Description of Change: Deleted text regarding vital signs, physical examination, 
peak flow or spirometry, and clinical assessment during BPCFC. 
Purpose for Change: Updated text regarding vital signs, physical examination, 
peak flow or spirometry, and clinical assessment during BPCFC provided under 
next sub heading (in the following paragraph). 
 

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13. Section 6.1.1 (Oral Blind Placebo-Controlled Food Challenge -Criteria for Monitoring 
and Stopping the Oral Food Challenge) 
Description of Change: Clarified language explaining timing of study procedures (vital 
signs, physical examination, peak flow or spirometry, and clinical assessment using oral 
food challenge Symptom Scoring Assessment Tool) during BPCFC. 
Purpose for Change: To provide clarity regarding timing for assessments (vital signs, 
physical examination, peak flow or spirometry, and clinical assessment) during BPCFC. 
 
14. Section 6.2.1 (Blood Volume) 
Description of Change: Updated blood volume to be collected at Screening and Day 1 
(Pre-dose) and added corresponding footnote.  
Purpose for Change: To reflect the extended collection window for ex vivo peanut 
challenge assay either at screening or on Day 1 and footnote provides additional detail on 
potential blood volumes. 
 
15. Section 6.2.2 (Day 1 Randomization) 
Description of Change: Added language to collect the blood sample for ex vivo peanut 
challenge assay on Day 1 if it was not collected during screening. 
Purpose for Change: To provide additional guidance regarding the blood sample 
collection window for ex vivo peanut challenge assay. 
 
16. Section 6.2.5 (End of Study) 
a. Description of Change: Added Day 45/46 BPCFC and corresponding procedures. 
Purpose for Change: To reflect addition of BPCFC at Day 45. 
b. Description of Change: Added text to specify EOS visit blood samples to be 
collected on Day 45. 
Purpose for Change: To provide clarity for collecting EOS visit blood samples if 
visit requires two days. 
 
17. Section 6.2.6 (Early Termination) 
Description of Change: Added instructions to perform BPCFC at the ET visit. 
Purpose for Change: To provide guidance on when to conduct the BPCFC if a patient 
terminates from the study before completing all study visits. 
18. Section 7.1.1.1 (Reporting of Adverse Events) 
Description of Change: Removed repetitive language. 
Purpose for Change: To provide clarity on AE reporting procedures. 
19. Section 7.1.3 (Vital Signs, Physical Findings, and Other Safety Assessments) 

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Description of Change: Clarified language explaining timing of study procedures (vital 
signs, physical examination, peak flow or spirometry, and clinical assessment using oral 
food challenge Symptom Scoring Assessment Tool) during BPCFC.   
Purpose for Change: To provide clarity regarding timing for assessments (vital signs, 
physical examination, peak flow or spirometry, and clinical assessment) during BPCFC. 
 
20. Section 7.4 (Efficacy) 
a. Description of Change: Added exploratory efficacy endpoints to assess on 
Day 45. 
Purpose for Change: To reflect the changes in the study design (to reflect addition 
of BPCFC on Day 45). 
b. Description of Change: Updated text regarding primary and secondary efficacy 
endpoints. 
Purpose for Change: To differentiate primary and secondary efficacy endpoints 
from the new exploratory efficacy endpoints. 
 
21. Section 9.5 (Efficacy analysis) 
a. Description of Change: Updated statistical analysis methods for primary and 
secondary endpoints analysis and added statistical analysis methods for new 
exploratory endpoints. 
Purpose for Change: To reflect the appropriate statistical analysis methods for 
endpoints based on the changes in the study design. 
b. Description of Change: Added exploratory efficacy endpoints and clarified 
primary and secondary endpoints. 
Purpose for Change: To reflect the changes in the study design. 
 
22. Section 18 (Appendix 2) 
a. Description of change: Added sample collection time points for Day 45 blood 
tests. 
Purpose for Change: To provide instruction for collecting the Day 45 blood 
samples prior to the BPCFC. 
b. Description of Change: Added footnote ‘d’ to reflect the window period for blood 
sample collection for ex vivo peanut challenge assay. 
Purpose for Change: Added to reflect the extended window period for blood 
sample collection for ex vivo peanut challenge assay either at screening or on   
Day 1.  
 
23. Administrative Change 

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Description of Change: Updated Contract Research Organization (CRO) name from 
Quintiles to QuintilesIMS. 
Purpose for Change: To reflect the updated CRO name. 
 
 
Protocol ANB020-003: Amendment 1, 01 DEC 2016 
Replaces: Original: 27 SEP 2016 
1. Protocol Cover Page  
Description of Change: Removal of “EnduraCT No.: 2016 002539 14” 
Purpose of change: Information not necessary for U.S. only protocol. 
 
2. Section 4.1; Table 4.1 (Schedule of Events) 
Description of Change: Added FSH at screening visit and additional footnote to indicate 
the criteria for testing FSH and collection visit.  
Purpose for Change: To include FSH in the screening safety laboratory assessment which 
was missing in the original protocol. 
3. Section 6.2.1 
Description of change: 
a. Updated the total blood volume and modified the text to be “The total blood 
volume for each patient will be approximately 177 mL.” 
b. Revised Table 6.1 (Blood Volume Sampling During Each Visit) to include the 
updated blood volume required on each study assessment day/visit. 
Purpose of change: To reflect the changes in the safety laboratory assessment and to 
reflect the changes in the amount of blood volume required for laboratory tests. 
4. Section 7.1.2; Table 7.1 (Clinical Laboratory Parameters) 
Description of change: Added Immunoglobulins (IgA, IgG, IgM, IgE, and IgD) under 
hematology panel. 
Purpose for Change: To include immunoglobulins in the safety laboratory assessments 
which were missing in the original protocol. 
5. Section 7.2 
Description of change: Updated the amount of blood volume required for 
pharmacodynamic test. 
Purpose for Change: To reflect the changes in the in the amount of blood required for 
pharmacodynamic laboratory test.