A Phase 2a Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Safety and Efficacy of Subcutaneous Benralizumab (MEDI-563) in Reducing Eosinophilia in Subjects With Hypereosinophilic Syndrome (HES)
Phase: PHASE2
Conditions: Respiratory System Agents, Anti-Asthmatic Agents, Hematologic Diseases, Leukocyte Disorders, Hypereosinophilia
Sponsor: National Institute of Allergy and Infectious Diseases (NIAID)

 
 
Title 
A Phase 2 Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the 
Safety and Efficacy of Subcutaneous Benralizumab in Reducing Eosinophilia in 
Subjects with Hypereosinophilic syndrome (HES)  
 
 
NIH Protocol Number: 14-I-0081 
NCT Number: 02130882 
 
 
Sponsored by:  
National Institute of Allergy and Infectious Diseases (NIAID) 
 
Pharmaceutical Support Provided by:  
AstraZeneca  
ESR-14-10008 
 
 
IND Sponsor:  
NIAID, NIH 
Office of Clinical Research Policy and Regulatory Operations (OCRPRO) 
IND #: 121696 
 
Benralizumab provided by: 
AstraZeneca 
1800 Concord Pike 
Wilmington DE 19850 
 
Principal Investigator: 
Amy Klion, MD, Laboratory of Parasitic Diseases, NIAID, NIH 
 
Version Number: 12.2 
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Table of Contents 
 
Title 
1 
Table of Contents 
2 
Protocol Summary 
8 
Précis 
11 
1 
Background Information and Scientific Rationale 
12 
1.1 
Background Information 
12 
1.1.1 
Description of the Study Agent 
12 
1.1.2 
Summary of Previous Pre-Clinical Studies 
12 
1.1.3 
Summary of Relevant Clinical Studies 
14 
1.2 
Rationale 
18 
2 
Study Objectives 
19 
2.1 
Primary Objective 
19 
2.2 
Secondary Objectives 
19 
2.3 
Exploratory Objectives 
19 
3 
Study Design 
20 
3.1 
Description of the Study Design 
20 
3.2 
Study Endpoints 
21 
3.2.1 
Primary Endpoint 
21 
3.2.2 
Secondary Endpoints 
21 
3.2.3 
Exploratory Endpoints 
22 
4 
Study Population 
22 
4.1 
Rationale for Subject Selection 
22 
4.2 
Recruitment Plan 
22 
4.3 
Subject Inclusion Criteria 
22 
4.4 
Subject Exclusion Criteria 
24 
4.5 
Justification for Exclusion of Children 
25 
5 
Study Agent/Interventions 
26 
5.1 
Disposition and Dispensation 
26 
5.1.1 
Formulation, Packaging and Labeling 
26 
5.2 
Study Agent Storage and Stability 
27 
5.3 
Preparation, Administration, and Dosage of Study Agent 
27 
5.3.1 
Study Drug Administration 
27 
5.3.2 
Study Drug Dosing 
29 
5.4 
Study Product Accountability Procedures 
29 
5.5 
Concomitant Medications and Procedures 
30 
5.6 
Prohibited Medications and Procedures 
30 
6 
Study Schedule 
30 
6.1 
Screening 
31 
6.2 
Enrollment/Baseline 
31 
6.3 
Randomization and Blinding 
32 
6.3.1 
Maintenance of Safety in the Face of Blinding 
33 
6.3.2 
Implications of Blinding on Safety Reporting 
33 
6.4 
Study Phase 
34 
6.5 
Follow-up 
35 

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6.6 
Final Study Visit/Early Termination Visit 
37 
6.7 
Open-label Extension 
37 
6.8 
Recontact of Subjects After Trial Termination 
38 
7 
Study Procedures/Evaluations 
38 
7.1 
Clinical Evaluations 
38 
7.1.1 
History and Physical Examination 
38 
7.1.2 
Symptom Questionnaire 
38 
7.1.3 
End Organ Assessment 
39 
7.2 
Laboratory Evaluations 
39 
7.2.1 
Routine laboratory testing 
39 
7.2.2 
Bone marrow biopsy and aspirate 
39 
7.2.3 
Exploratory assessments 
40 
8 
Potential Risks and Benefits 
40 
8.1 
Potential Risks 
40 
8.1.1 
Blood Drawing 
40 
8.1.2 
Benralizumab 
40 
8.1.3 
Bone marrow biopsy 
42 
8.2 
Potential Benefits 
42 
9 
Research Use of Stored Human Samples, Specimens or Data 
42 
10 
Remuneration Plan for Subjects 
43 
11 
Assessment of Safety 
43 
11.1 
Definitions 
43 
11.2 
Documenting, Recording and Reporting Adverse Events 
46 
11.3 
Investigator Assessment of Adverse Events 
46 
11.3.1 
Severity 
47 
11.3.2 
Causality 
47 
11.4 
Investigator Reporting Responsibilities to the Sponsor 
48 
11.4.1 
Adverse Events 
48 
11.4.2 
Serious Adverse Events 
48 
11.4.3 
Unanticipated Problems 
48 
11.4.4 
Pregnancy 
48 
11.5 
Investigator Reporting Responsibilities to the IRB and NIAID 
49 
11.5.1 
NIH IRB Reporting 
49 
11.5.2 
Reporting to the NIAID Clinical Director 
49 
11.6 
Investigator Reporting Responsibilities to the Drug Supplier 
49 
11.7 
Follow-up of Adverse Events and Serious Adverse Events 
49 
11.8 
Sponsor’s Reporting Responsibilities 
50 
11.9 
Halting Rules for the Protocol 
50 
11.9.1 
Reporting of Study Halting 
50 
11.9.2 
Resumption of a Halted Study 
50 
11.10 
Pausing Criteria for a Subject or Group 
50 
11.10.1 
Reporting of Pausing for a Subject or Group 
51 
11.10.2 
Resumption of a Paused Study 
51 
11.11 
Withdrawal Criteria for an Individual Subject 
51 
11.12 
Replacement of a Subject Who Discontinues Study Treatment 
52 
11.13 
Unblinding of the study 
52 

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11.13.1 
Scheduled unblinding 
52 
11.13.2 
Intentional Unscheduled Unblinding for Treatment Conditions 
52 
11.13.3 
Reporting of Unblinding 
52 
11.14 
Safety Oversight 
52 
11.14.1 
Safety Review and Communications Plan (SRCP) 
52 
11.14.2 
Sponsor Medical Monitor (SMM) 
52 
11.14.3 
Data and Safety Monitoring Board (DSMB) 
53 
11.14.4 
Unblinded Pathologist 
53 
12 
Clinical Monitoring Structure 
53 
12.1 
Site Monitoring Plan 
53 
13 
Statistical Considerations 
54 
13.1 
Study Hypotheses 
54 
13.2 
Sample Size Justification 
54 
13.3 
Description of the Analyses 
55 
13.4 
Final Analysis Plan 
56 
14 
Ethics/Protection of Human Subjects 
56 
14.1 
Informed Consent Process 
57 
14.2 
Subject Confidentiality 
57 
15 
Data Handling and Record Keeping 
57 
15.1 
Data Capture and Management 
57 
15.2 
Record Retention 
58 
Appendix A: Scientific References 
59 
Appendix B: Schedule of Procedures/Evaluations 
61 
Appendix C: Blood Volumes for Specimen Collection 
64 
Appendix D: Research Studies 
66 
Appendix E: HES Questionnaire 
69 
Appendix F: FASENRA PEN: Instructions for Use 
70 
 
List of Tables 
 
Table 1 
Benralizumab (MEDI-563) composition ...................................................... 26 
Table 2 
Power Estimates ........................................................................................ 54 
 
List of Figures 
 
Figure 1 
Effect of benralizumab on the accumulation of eosinophils following Ascaris 
suum antigen inhalation in sensitized cynomolgus monkeys ..................... 14 
Figure 2 
Injection sites and rotation scheme ............................................................ 27 

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List of Abbreviations 
 
ACQ  
Asthma Control Questionnaire 
ADA  
Anti-Drug Antibodies 
ADCC  
Antibody-dependent Cellular Cytotoxicity  
AE 
 
Adverse Event/Adverse Experience 
AEC  
Absolute Eosinophil Count 
AER  
Asthma Exacerbation Rate 
AHR  
Airway Hyperresposiveness 
APFS  
Accessorized Prefilled Syringe 
AR 
 
Adverse Reaction 
CBC  
Complete Blood Count  
CC 
 
Clinical Center 
CFR  
Code of Federal Regulations 
COPD  
Chronic Obstructive Pulmonary Disease 
CPT  
Center Point Titer 
CRF  
Case Report Form 
CRP  
C-Reactive Protein 
CRIMSON 
Clinical Research Information Management System of the 
 
 
National Institute of Allergy and Infectious Diseases 
CS 
 
Corticosteroid 
CSO  
Clinical Safety Officer 
CTCAE 
Common Terminology Criteria for Adverse Events 
DCR  
Division of Clinical Research 
DHHS  
Department of Health and Human Services 
DSMC 
Data and Safety Monitoring Committee 
ECG  
Electrocardiogram 
ePPND 
enhanced pre- and post-natal development 
ESR  
Erythrocyte Sedimentation Rate 
FDA  
Food and Drug Administration 
FEV  
Forced Expiratory Volume 
FIP1L1 
Fip-1-like-1 
FWA  
Federal Wide Assurance 
GCP  
Good Clinical Practice 
HCG  
Human Chorionic Gonadotropin 
HES  
Hypereosinophilic Syndrome 
HGB  
Hemoglobin 
HIV 
 
Human Immunodeficiency Virus 
IB 
 
Investigator’s Brochure 
ICF 
 
Informed Consent Form 
ICH 
 
International Conference on Harmonization 
ID 
 
Identification 
IEC 
 
Independent or Institutional Ethics Committee 
IG 
 
Immunoglobulin 
IL 
 
Interleukin 

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IL-5R  
Interleukin 5 receptor 
IND 
 
Investigational New Drug 
IRB 
 
Institutional Review Board 
ISM 
 
Independent Safety Monitor 
IUD 
 
Intrauterine Device 
IV 
 
Intravenous 
KLH  
Keyhole Limpet Hemocyanin 
LHES  
Lymphocytic Variant Hypereosinophilic Syndrome 
LPD  
Laboratory of Parasitic Diseases 
LVEF  
Left Ventricular Ejection Fraction 
MAb  
Monoclonal Antibody 
MRI 
 
Magnetic Resonance Imaging 
N 
 
Number (typically refers to number of subjects/sample size) 
NCI 
 
National Cancer Institute, NIH 
NIAID  
National Institute of Allergy and Infectious Diseases  
NIH 
 
National Institutes of Health 
NK 
 
Natural Killer 
NOAEL 
No-Observed Adverse-Effect-Level 
NYHA  
New York Heart Association 
OCRPRO 
Office of Clinical Research Policy and Regulatory Operations  
OHRP  
Office for Human Research Protections 
OHSRP 
Office of Human Subjects Research Program 
OTC  
Over-the-Counter  
PBMC  
Peripheral Blood Mononuclear Cells 
PDGFRA 
Platelet-derived growth factor receptor alpha 
PHI 
 
Protected Health Information 
PI 
 
Principal Investigator 
PK 
 
Pharmacokinetics 
PT 
 
Prothrombin Time 
PTT 
 
Partial Thromboplastin Time 
QA 
 
Quality Assurance 
QC 
 
Quality Control 
RBC  
Red Blood Cell Count 
RCHSPP 
Regulatory Compliance and Human Subjects Protection Program 
SAE  
Serious Adverse Event/Serious Adverse Experience 
SAR  
Serious Adverse Reaction 
SC 
 
Subcutaneous 
SD 
 
Standard Deviation 
SMC  
Safety Monitoring Committee 
SMM  
Sponsor Medical Monitor 
SOP  
Standard Operating Procedure 
SRCP  
Safety Review and Communications Plan 
SUSAR 
Suspected and Unexpected Serious Adverse Reaction 
TARC  
Thymus and activation-regulated chemokine 
Tdap  
Tetanus-diphtheria-acellular pertussis 
Th2 
 
T helper 2 

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TCR  
Tissue cross-reactivity 
TEAE  
Treatment-Emergent Adverse Events 
TK 
 
Toxicokinetics 
UP 
 
Unanticipated Problem 
UPnonAE 
Unanticipated Problem that is not an Adverse Event 
 

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Protocol Summary 
Full Title:  
 
 
A Phase 2 Randomized, Double-Blind, Placebo-Controlled 
Study to Evaluate the Safety and Efficacy of Subcutaneous 
(sc) Benralizumab in Reducing Eosinophilia in Subjects with 
Hypereosinophilic syndrome (HES)  
 
Short Title: 
Benralizumab for treatment-refractory HES 
Clinical Phase: 
2 
IND Sponsor: 
 
OCRPRO/NIAID/NIH  
Conducted by: 
 
NIAID/LPD 
Principal Investigator: 
Amy Klion, MD 
Sample Size: 
N=20  
Accrual Ceiling: 
N=25 
Study Population:  
Adult subjects aged 18-75 with PDGFRA-negative HES who 
are are symptomatic with AEC >1000/µL on stable HES 
therapy for at least 1 month 
Accrual Period: 
 
2 years 
Study Design: 
This will be a randomized, placebo-controlled, double-blind 
study followed by an open-label extension. A maximum of 20 
subjects will be randomized (1:1) to receive sc injections of 
30 mg of benralizumab or placebo at 0, 4 and 8 weeks. 
Eosinophil counts for a subject will be blinded and 
background HES therapy will not be tapered until that 
subject has reached 13 weeks on study. Beginning at the 12 
week visit, all subjects will receive open-label benralizumab 
(30 mg sc) every 4 weeks for 3 doses. Subjects with an 
AEC<1000/µL and improvement in clinical symptoms without 
an increase in background HES therapy (responders) at the 
24 week visit will continue to receive benralizumab every 4 
weeks for the duration of the study (1 year). Non-responders 
will not receive additional doses of benralizumab. Following 
the initial dose of benralizumab or placebo and the first 
open-label (at 12 weeks) dose of benralizumab, subjects will 
be followed daily for 3 days, weekly for 4 weeks, and every 2 
weeks for 8 weeks. Subsequent visits will be at 4 weeks 
intervals for responders and at 12 week intervals for non-
responders for the duration of the study. For subjects who 
complete the study and for whom benralizumab provides 
sustained clinical benefit, drug may be provided on an open-
label extension. After 2 years of stable and complete 
response to benralizumab, the dosing interval may be 
increased to every 8 weeks. Subjects will receive diphtheria-

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tetanus-acellular pertussis (TdaP) booster immunization at 
the 22 week visit. Titers will be measured 6 weeks after 
immunization. Subjects with a sustained and complete 
response to benralizumab with a stable dose for another 
2 years will be transitioned to the FasenraPEN autoinjector 
for at-home self-administration (or by a local provider), with 
monthly blood counts and visits to the NIH once every 
6 months. 
 
Study Duration: 
 
Start Date:  March 2014 End Date: June 2025 
 
 
Subjects will be on study for 12 months (or longer if enrolled 
on the open label extension). 
Study Agent/  
Intervention Description: Benralizumab (30 mg sc) every 4 weeks 
Primary Objective:  
To determine the efficacy of 3 doses of sc benralizumab in 
reducing eosinophilia in subjects with PDGFRA-negative 
HES 
Secondary Objectives: 
To assess the safety of sc benralizumab in reducing 
eosinophilia in subjects with HES 
To assess the effect of benralizumab on end organ 
manifestations of HES 
To investigate the effects of benralizumab on bone marrow 
eosinophils, mast cells and their precursors 
To assess the long-term safety and efficacy of sc 
benralizumab in reducing eosinophilia in subjects with HES 
 
 
To evaluate the pharmacokinetics (PK) and immunogenicity 
of benralizumab in HES 
 
 
To determine the efficacy of every 8 week dosing in HES 
Exploratory Objectives:  
 
 
To determine predictors of response to benralizumab in 
subjects with HES 
 
 
To assess the effects of eosinophil depletion on vaccine 
responses and glucose homeostasis in humans 
Endpoints: 
 
Primary Endpoints:  
- 
50% reduction in peripheral blood eosinophilia on stable 
HES background therapy at 12 weeks post-initiation of 
study drug  
 
 
Secondary Endpoints: 
- 
Percent reduction in peripheral blood eosinophilia at 12 
weeks post-treatment 
- 
Frequency and severity of AEs 
- 
Reduction in signs and symptoms of HES 

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- 
Tissue eosinophilia 
- 
Numbers of eosinophils, mast cells and their precursors 
in bone marrow 
- 
Levels of markers of eosinophil and mast cell activation 
- 
Eosinophil count and background HES therapy at 1 year 
- 
PK and anti-drug antibody (ADA) levels  
- 
Eosinophil count after 24 weeks of every 8 week 
benralizumab dosing  
Exploratory Endpoints: 
- 
Correlation between IL5 receptor levels and reduction in 
peripheral blood eosinophilia at 1, 4 and 12 weeks  
- 
Change in anti-tetanus antibody titers at 6 weeks post-
immunization 
- 
Differences between weight and hemoglobin (Hgb) A1c 
levels at baseline and after 12 and 24 weeks of 
benralizumab therapy 
 

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Précis 
 
Hypereosinophilic syndrome (HES) is a rare group of heterogeneous disorders 
characterized by marked peripheral eosinophilia (>1500/µL) and evidence of eosinophil-
associated tissue damage. Although a high proportion of patients respond initially to 
corticosteroid therapy, high doses are often necessary to control the eosinophilia and 
clinical symptoms, and many patients become relatively refractory to therapy and/or 
develop serious side effects. IL-5 receptor a (IL-5Ra) expression in humans is restricted 
to eosinophils, basophils, mast cells and their precursors and is, therefore, an ideal 
target for the therapy of HES. Benralizumab was approved in the US in 2017 for 
treatment of severe asthma in patients 12 years or older and with eosinophilic 
phenotype. The product has a well-established safety profile based on several years of 
post-market experience for severe asthma since its approval. In order to explore the 
safety and efficacy of benralizumab in the treatment of HES, 20 adults (men and non-
pregnant women, 18-75 years of age) with HES who are symptomatic with AEC 
>1000/µL on stable HES therapy for at least 1 month will be recruited for this 
randomized, placebo-controlled, double-blind phase 2 trial. Benralizumab (30 mg) or 
placebo will be administered sc at weeks 0, 4, and 8. Eosinophil counts will be blinded 
for a subject and background HES therapy will not be tapered until that subject has 
been on study for 13 weeks. At weeks 12, 16, and 20, all subjects will  receive a sc 
injection of benralizumab. Subjects demonstrating a response at the 24 week visit  
(eosinophil count <1000/µL and stable or improved clinical symptoms without an 
increase in background HES therapy) will continue to receive additional 30 mg sc 
injections every 4 weeks. Following the initial dose of benralizumab or placebo and the 
first open-label dose of benralizumab, subjects will be followed daily for 3 days, weekly 
for 4 weeks, and every 2 weeks for 8 weeks. Subsequent visits will be at 4 weeks 
intervals for responders and 12 weeks intervals for non-responders for a minimum of 
two years. Subjects with stable and complete response for ≥2 years may be eligible to 
receive benralizumab at a dosing interval of every 8 weeks. Subjects will receive 
diphtheria-tetanus-acellular pertussis (TdaP) booster immunization at the 22 week visit. 
Titers will be measured 6 weeks after immunization.The primary endpoint of the study is 
a 50% reduction in peripheral blood eosinophilia on stable background therapy at 12 
weeks post-initiation of study drug. Secondary endpoints will include absolute eosinophil 
count, the frequency and severity of adverse events, reduction in signs and symptoms 
of HES, tissue eosinophilia, numbers of eosinophils, mast cells and their precursors in 
bone marrow, levels of markers of eosinophil and mast cell activation, eosinophil count 
and background HES therapy at 1 year, pharmacokinetics and anti-drug antibody (ADA) 
levels and eosinophil count after 24 weeks of every 8 week dosing. Exploratory 
endpoints will address predictors of response to benralizumab and the impact of 
eosinophil depletion on vaccine responses and glucose homeostasis. Subjects who 
complete the study and for whom benralizumab provides sustained clinical benefit, may 
be eligible to receive drug on an open-label extension protocol until regulatory approval 
and commercial availability of the marketed drug to prescribing physicians (for any 
indication), or until development of benralizumab is discontinued by AstraZeneca. 

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1 Background Information and Scientific Rationale 
1.1 
Background Information 
 
Hypereosinophilic syndrome (HES) is a rare group of heterogeneous disorders 
characterized by marked peripheral eosinophilia (>1500/µL) and evidence of eosinophil-
associated tissue damage. Treatment is directed at reducing peripheral blood and 
tissue eosinophilia. With the exception of Fip1-like-1/platelet derived growth factor 
receptor alpha (FIP1L1/PDFGRA)-positive chronic eosinophilic leukemia, first line 
therapy for all of the varied forms of HES is corticosteroids (CS). Although a high 
proportion of patients respond initially to CS therapy, high doses are often necessary to 
control the eosinophilia and clinical symptoms, and many patients become relatively 
refractory to therapy and/or develop serious side effects (1). Second line agents, 
including hydroxyurea and interferon, are effective in only a subset of patients and are 
associated with considerable toxicity.  Despite the recent success with mepolizumab, a 
monoclonal antibody to IL-5, as a steroid-sparing agent in steroid-responsive subjects 
with HES (2, 3), 15% of steroid-responsive patients did not respond and the response 
rate in steroid-refractory patients is likely lower. Furthermore, early studies in asthma 
suggested that anti-IL5 therapy is associated with maturational arrest in the bone 
marrow (4) that can lead to rebound eosinophilia and symptoms when the drug is 
discontinued (5). This rebound has been seen with both of the anti-IL-5 antibodies 
currently in clinical trials and is associated with increased serum levels of biologically 
active IL-5. Clearly, additional targeted therapies are needed. 
1.1.1 Description of the Study Agent 
Expression of the human IL-5Rα chain is restricted to eosinophils, basophils, and mast 
cells and their precursors (6, 7). Benralizumab is a humanized, afucosylated 
monoclonal antibody (mAb) that binds specifically to the alpha subunit of the human 
interleukin-5 receptor (IL-5Ra). It specifically targets and depletes IL-5Ra-bearing cells 
by inducing apoptosis via enhanced antibody-dependent cell-mediated cytotoxicity 
(ADCC) (7-9).  The parental murine clone (KM1259) was humanized by grafting of the 
corresponding complementary determining regions onto human framework sequences. 
Benralizumab is formatted as a human immunoglobulin of the G1/kappa isotype (IgG1k). 
It comprises 2 heavy chains (G1) and 2 light chains (k) and has an overall molecular 
weight of approximately 150 kDa. The afucosylated form of this recombinant humanized 
IgG1 is produced in a CHO-DG44 BioWa-afuc cell line deficient in a1,6-fucosyl 
transferase (FUT8).Appendix_A:_Scientific 
1.1.2 Summary of Previous Pre-Clinical Studies  
Nonclinical pharmacologic and safety studies conducted in cynomolgus monkeys with 
benralizumab included a 9-week repeated-dose intravenous (IV) study, a single-dose sc 
study; a 15-week repeated-dose SC study, a 9-month repeated-dose IV and SC study, 
and a reproductive toxicology study (enhanced pre- and post-natal development 
[ePPND]) (10).  As expected, eosinophil counts were markedly decreased in all 
benralizumab-treated animals throughout the dosing and recovery periods.  In the 9-

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week repeated-dose IV study, transient decreases in leukocytes, resulting from 
differential decreases in neutrophils counts, were seen in 2 of 10 animals  
(1 male and 1 female) treated with the highest dose (30 mg/kg) resulting in a no 
observed adverse effect level (NOAEL) of ≤30.0 mg/kg.  In the 9-month repeated-dose 
IV and SC study, there were no benralizumab-related adverse effects (AEs) observed, 
including for male and female fertility parameters, resulting in NOAELs of 25 mg/kg for 
IV and 30 mg/kg for SC, the highest doses tested.  In a rabbit local tolerance study with 
SC administered benralizumab, no benralizumab-related adverse effects were 
observed.  Finally, the tissue cross-reactivity (TCR) of benralizumab was assessed in a 
panel of normal human and cynomolgus monkey tissues.  Both the human and 
cynomolgus monkey TCR profiles were generally consistent with those in literature. 
 
Findings from the ePPND reproductive toxicology study indicated no adverse maternal 
effects of benralizumab administration, and the growth and development of the infants 
were within normal limits for infant cynomolgus monkeys, including immune 
assessments (keyhole limpet hemocyanin [KLH] immunization; immunoglobulin M [IgM] 
and immunoglobulin G [IgG] center point titer (CPT) values; and serum IgG, IgM, and 
immunoglobulin A [IgA] levels), resulting in a NOAEL of 30 mg/kg/dose, the highest 
dose tested. 
 
Toxicokinetic(s) (TK) and immunogenicity evaluations of benralizumab were 
investigated in cynomolgus monkeys following single- and repeated-dose IV and SC 
administration of benralizumab up to the highest dose of 30 mg/kg.  The TK of 
benralizumab in cynomolgus monkeys were linear with dose in the 1-30 mg/kg dose 
range among various TK studies.  The absorption of benralizumab was slow, with the 
peak serum concentration occurring approximately 3 days after dosing.  The TK of 
benralizumab was similar in male and female cynomolgus monkeys.  Distribution of 
benralizumab from maternal plasma to neonates was observed and was consistent with 
placental transfer from maternal circulation into fetal circulation.  The TK parameter 
values for benralizumab in cynomolgus monkeys were typical of an IgG1 mAb without 
an antigen sink.  Anti-drug antibodies (ADA) were detected in some benralizumab-
treated animals.  High-titer ADA was associated with reduced TK exposure in 
cynomolgus monkeys. 
 
The clinical efficacy of benralizumab was tested in cynomolgus monkeys receiving 
recombinant IL-5 sc and in a monkey asthma model, in which 5 cynomolgus monkeys 
that had no skin reaction to SC injection of Ascaris antigen were immunized with 6 
injections of antigen, administered 4 times intramuscularly and on 2 occasions by 
inhalation (8).  In the first study, benralizumab (0.01 mg/kg or 0.3 mg/kg) dramatically 
reduced the IL-5 induced peripheral eosinophilia in 4/6 animals. In the second study, the 
effect of the anti-IL-5R mAb on reactivity to inhaled antigen was evaluated by injecting a 
single IV dose of benralizumab (1 mg/kg) into the animals at Week 24 after the first 
immunization.  The number of accumulated eosinophils following antigen inhalation in 
the cynomolgus monkeys who received benralizumab was dramatically decreased over 
a period of 14 weeks after monoclonal antibody  (mAb) administration (Figure 1).   
 

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Figure 1 
Effect of benralizumab on the accumulation of eosinophils following 
Ascaris suum antigen inhalation in sensitized cynomolgus monkeys 
  
 
 
 Benralizumab (KHK4563); W  Week. 
Open bars depict the mean number of eosinophils in BAL fluids of the 5 monkeys before antigen challenge. Filled 
bars indicate the mean number of eosinophils in BAL fluids of the 5 monkeys after antigen challenge.  Results are 
expressed as mean±SD of number of eosinophils in BAL fluids for each time point. 
 
Airway hyperresponsiveness (AHR) was evaluated in the 2 animals that tested positive 
for antigen reactivity.  Tests were performed 1 week after mAb injection and then 3, 8, 
18, and 23 weeks after benralizumab injection. Benralizumab suppressed the 
development of AHR for over 23 weeks in one of these animals. 
 
Additional pre-clinical information can be obtained from the Investigator Brochure.  
 
1.1.3 Summary of Relevant Clinical Studies 
Benralizumab has been or is being investigated in adult subjects and adolescents with 
asthma (20 studies), adults with chronic obstructive pulmonary disease (COPD) (3 
studies) and nasal polyposis (1 study). A full list of clinical trials can be found in the 
Investigator’s Brochure.  Kyowa Hakko Kirin Co, Ltd is developing 
benralizumab/KHK4563 in Asia and has completed 2 Phase 1 studies (Studies 4563-
001 and 4563-002) in healthy adult Japanese subjects and a Phase 2a study (Study 
4563-003) in adult subjects with asthma (18). A phase 2 study in rhinosinusitis is 
ongoing. Overall, benralizumab has been administered to more than 40 healthy 
Japanese men, 2500 subjects with asthma and 250 subjects with COPD.  
 
Safety. 
 
Results of the AstraZeneca-sponsored asthma studies (Studies MI-CP158, MICP166, 
MI-CP186, MI-CP197, and MI-CP220) showed no emerging safety findings. As reflected 
in the analysis of study MI-CP220, a placebo controlled study of sc multiple dose 
benralizumab in 609 adults with asthma, treatment-emergent adverse events (TEAE), 

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regardless of causality, occurred at an approximate 10 percentage point higher 
frequency in the combined benralizumab group compared with the placebo group with 
events classified as Infections, General Disorders and Administration Site Conditions, 
and Musculoskeletal and Connective Tissue Disorders largely accounting for this 
difference.   
 
Treatment-emergent adverse events within each of these classifications that occurred at 
least 5 percentage points higher in the combined benralizumab group than in the 
placebo group were as follows: 
• Infections: Nasopharyngitis, upper respiratory tract infection, and pharyngitis  
• General Disorders and Administration Site Conditions: Asthenia, contusion, 
hypotension, injection site erythema, injection site reaction, and pyrexia 
• Musculoskeletal and Connective Tissue Disorders: Muscle spasm and pain 
Treatment-emergent adverse events classified as Respiratory, Thoracic, and 
Mediastinal disorders were the most frequently occurring in both the placebo and 
combined benralizumab groups, with asthma being the most frequently occurring TEAE.  
 
No apparent dose response on the incidence of TEAEs was observed across the 
individual benralizumab dose groups.  The majority of these TEAEs were mild or 
moderate in severity.  Severe TEAEs, regardless of causality, occurred in 20/221 
subjects (9.0%) in the placebo group and 47/385 subjects (12.2%) in the combined 
benralizumab group.  
 
Infusion-related reactions may be defined as any signs or symptoms experienced by 
subjects during the infusion of pharmacologic or biologic agents or any event occurring 
on the first day of drug administration.  Such reactions may occur after administration of 
benralizumab. Clinical manifestations of these reactions vary.  Anaphylactic or 
anaphylactoid reactions are the most severe forms of infusion-related reactions and 
may result in death.  Infusion-related reactions usually develop within 2 hours of the 
start of investigational product administration and often resolve within 24 hours after 
completion of investigational product administration. Signs/symptoms may include the 
following: urticaria, arthralgia, bronchospasm, wheeze, cough, dizziness, dyspnea, 
fatigue, headache, hypertension, hypotension, myalgia, and vomiting. 
 
The ALIZE trial was designed as a randomized, double-blind, parallel group, placebo-
controlled study designed to investigate the potential efficacy, safety, PK, and 
immunogenicity effect of a fixed dose of benralizumab on the humoral immune 
response following seasonal influenza virus vaccination in adolescent or young adult 
patients with severe asthma. Antibody titers at 12 weeks post-vaccination were similar 
across strains and between treatment groups (ranged from 78.0% to 100.0% for the 
benralizumab treatment group and from 79.6% to 100.0% for the placebo treatment 
group). 
 

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Suppression of eosinophilia.  
 
Benralizumab exhibited pharmacological activity as evidenced by suppression of 
peripheral blood eosinophil counts in all clinical studies, and in Study MI-CP166, 
suppression of eosinophil counts (including eosinophils undergoing apoptosis) in airway 
mucosal biopsies after single IV and multiple SC doses of benralizumab. In study MI-
CP158, a dose escalation safety study of single dose IV benralizumab in 44 adult 
subjects with mild asthma, mean time to eosinophil recovery following a single IV dose 
of benralizumab ranged from 5.8 days (0.0003 mg/kg) to 190 days (3.0 mg/kg) (9).  
Similar results were observed in study MI-CP186, a Phase 2 study of single dose 
benralizumab (0.3 or 1 mg/kg IV) vs. placebo in 110 adults with asthma exacerbation, in 
which depletion of blood eosinophil counts was observed through the last scheduled 
visit on Day 84 in all 72 subjects who received benralizumab and in study MI-CP197, a 
Phase 2 study of 3 doses of benralizumab (0, 25, 100 or 200 mg sc every 4 weeks) in 
25 adults with asthma, in which peripheral blood eosinophils had decreased by at least 
95% at all benralizumab dose levels by Day 7 and remained <20% of baseline for 57-
239 days. 
 
MI-CP220, a Phase 2 double-blind, placebo-controlled dose-ranging study of 
benralizumab (2, 20 or 100 mg sc every 4 weeks for 3 doses followed by every 8 weeks 
for 4 doses) in 609 adult subjects with uncontrolled eosinophilic or non-eosinophilic 
asthma requiring medium to high dose inhaled corticosteroids. Blood eosinophil 
depletion was seen across all benralizumab dose groups regardless of eosinophilic 
phenotype.  No blood eosinophil depletion was observed in the placebo group. Median 
blood eosinophil counts have remained ≤ 100 cells/μL through Week 52. A similar study 
(4563-003) was conducted in Japan with comparable results (18).  
 
Study MI-CP166, a multicenter, double-blind placebo controlled study in 27 subjects 
with eosinophilic asthma, examined the effect of single dose iv or multiple dose sc 
benralizumab on eosinophil counts in airway mucosa/submucosa, sputum, bone 
marrow and peripheral blood (11). In cohort 1, intravenous benralizumab produced a 
median decrease from baseline of 61.9% in airway mucosal eosinophil counts (Day 28; 
placebo: +19.6%; P = .28), as well as an 18.7% decrease (Day 21) in sputum and a 
100% decrease (Day 28) in blood counts. Eosinophils were not detectable in bone 
marrow of benralizumab-treated subjects (Day 28, n = 4). In cohort 2 sc benralizumab 
demonstrated a combined (100 + 200 mg) median reduction of 95.8% in airway 
eosinophil counts (Day 84; placebo, 46.7%; P = .06), as well as an 89.9% decrease 
(Day 28) in sputum and a 100% decrease (Day 84) in blood counts. 
 
Clinical efficacy in asthma. 
 
The effect of benralizumab on measures of asthma clinical disease activity and quality 
of life were exploratory endpoints in Studies MI-CP158, MI-CP166, and MI-CP197 and 
were difficult to interpret because of the small sample size, mild asthmatic population, 
and variability of baseline disease characteristics. 

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In Study MI-CP186, a statistically significant reduction in the rate of asthma 
exacerbations and asthma exacerbations that resulted in hospitalizations (p=0.007 and 
p=0.022, respectively) among adult subjects who required an urgent healthcare visit for 
treatment of an acute asthma exacerbation was observed in benralizumab-treated 
subjects compared with placebo.  In Study MI-CP220, the primary endpoint of the study 
was met as there was a statistically significant 41% reduction in the annual asthma 
exacerbation rate (AER) in the EOS+ 100 mg benralizumab group versus the EOS+ 
placebo group (p = 0.096). Similar results were seen for patient-reported outcome 
(Asthma Control Questionnaire 6 [ACQ6]) and spirometry measures.  
 
Three large phase 3 studies in asthma (SIROCCO, CALIMA and ZONDA) have been 
completed and confirmed that benralizumab is well-tolerated and effective in reducing 
asthma exacerbations in adult and adolescent patients with eosinophilia (16, 17,19).  
Benralizumab (30 mg every 8 weeks) was approved (November 14 2017) by the FDA 
as add-on therapy for patients 12 years or older with severe eosinophilic asthma. 
AppendixA 
 
Additonal trials have demonstrated the efficacy of benralizumab in mild to moderate 
asthmatics (BISE) and the ability of the majority (93%) of subjects with severe asthma 
to self-administer benralizumab at home using a pre-filled syringe (GREGALE).  
 
Clinical efficacy in COPD.  
 
Results from Study MI-CP196, performed in patients with sputum eosinophils >3%, 
indicated that benralizumab was not superior to placebo in exacerbation rate reduction. 
In a prespecified subgroup, analysis of the primary endpoint was perform.ed using the 
baseline blood eosinophil count cutpoints of ≥/<150, ≥/<200, and ≥/< 300 cells/μL); 
these analyses did suggest an increasing treatment effect for benralizumab compared 
to placebo on the moderate or severe AECOPD rate through Day 393 for the 
benralizumab group compared with the placebo group for subjects with a baseline blood 
eosinophil count of ≥ 200 cells/μL (AECOPD rate 1.06 placebo and 0.73 benralizumab) 
and ≥ 300 cells/μL (AECOPD rate 0.93 placebo and 0.39 benralizumab). This finding 
was not replicated in those subjects with a blood eosinophil count of < 200 cells/μL, 
where the exacerbation rate was lower in the placebo group. IN view of these data, 
additional studies were initated and are ongoing.  
 
Pharmacokinetics and drug metabolism.  
 
Based on data from studies MI-CP158, MI-CP166, MI-CP186, MI-CP197, and MI-
CP220, benralizumab PK was dose-proportional in the dose range investigated in 
humans (0.03-3.0 mg/kg IV and 25-200 mg SC).  The t1/2 was approximately 2-3 weeks.  
From population PK meta-analysis, the systemic clearance and the distribution volumes 
were typical for human IgG.  The SC bioavailability was approximately 52%.  Both drug 
clearance and volume of distribution increased with body weight.  Age, gender, race, 

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and tobacco smoking history had no apparent impact on PK of benralizumab in asthma 
subjects.   
 
Anti-drug antibodies (ADA) were associated with reduced PK exposure in some 
subjects. In MI-CP220, ADA (titers ≥50) were detected in 15/220 subjects (6.8%) in the 
placebo group and 89/382 subjects (23.3%) in the combined benralizumab group, with 
little increase in incidence beyond Week 24. The presence of ADA was highest in the 
lowest benralizumab dose, but not more frequent in those subjects with blood 
eosinophils ≥300 cells/μL (20.7%) as compared to those with blood eosinophils <300 
cells/μL (21.7%).  Samples from the 23 subjects who were ADA-positive also tested 
positive for neutralizing antibodies, and the presence of ADA titers ≥400 was associated 
with a decrease in benralizumab concentrations and an increase in the number of 
eosinophils present in the blood. 
 
Pregnancy. To date, one female study patient receiving open-label benralizumab in the 
current study became pregnant. Her daughter was delivered at term without 
complications.  CBC revealed 0 eosinophils/mm3 at birth 1, and 4 month of age and a 
count of 280/mm3 at 9 months of age. Her growth has been normal for age, and she has 
met all developmental milestones. A registry of pregnant women receiving benralizumab 
has been established by the Organization of Teratology Information Specialists 
( https://mothertobaby.org/ongoing-study/fasenra/). No data is available at this time.  
 
 
1.2 
Rationale 
 
IL-5Ra expression in humans is restricted to eosinophils, basophils, mast cells and their 
precursors (6,7) and is, therefore, an ideal target for the therapy of HES.  Benralizumab, 
a humanized afucosylated antibody to IL-5Ra, has been shown to be safe in Phase 1, 2 
and 3 trials in humans (9, 16-18 and Investigator’s Brochure). Furthermore, data from 
animal models and asthma studies in humans suggest that eosinophilia is suppressed 
for up to 6 months, consistent with an effect on precursors in the bone marrow (9-11). 
Finally, benralizumab is unlikely to cause rebound eosinophilia and symptoms when the 
drug is discontinued since it acts by inducing apoptosis of IL-5Ra bearing cells and, in 
contrast to mepolizumab, causes a decrease in eosinophils and CD34+IL5Ra+ 
eosinophil precursors in the marrow (11).  Although patients with HES do have a mild 
increase in bone marrow mast cells, marked increases in numbers and activation status 
of mast cells are seen only in patients with PDGFRA-associated myeloproliferative 
neoplasms.  Furthermore, rapid reduction of eosinophil or mast cell numbers using 
targeted therapies such as imatinib (in PDGFRA-associated myeloproliferative 
neoplasms and imatinib-sensitive systemic mastocytosis) or mepolizumab (in HES) has 
not been associated with signs or symptoms consistent with a tumor lysis syndrome. 
Thus, benralizumab is anticipated be a safe and effective eosinophil-lowering agent in 
patients with HES.  
 

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Since murine eosinophils have been shown to play a role in the maintenance of plasma 
cells in the bone marrow (12) and alternatively activated macrophages in adipose tissue 
(13) that are involved in glucose homeostasis and responses to immunization, 
respectively, prolonged depletion of eosinophils in the blood and bone marrow following 
benralizumab treatment provides a unique opportunity to examine the relevance of 
these findings in humans.  It should be noted, however, that eosinophil-deficient mice 
do not demonstrate increased susceptibility to diabetes, obesity or infection (14, 15).  
 
2 Study Objectives 
 
2.1 
Primary Objective 
 
The primary objective of the study will be to determine the efficacy of 3 monthly sc 
doses of benralizumab in reducing eosinophilia in adult subjects with PDGFRA-negative 
HES. 
 
2.2 
Secondary Objectives  
 
The secondary objectives will be: 
1) 
To assess the safety of sc benralizumab in reducing eosinophilia in 
subjects with HES 
2) 
To assess the effect of benralizumab on end organ manifestations 
of HES 
3) 
To investigate the effects of benralizumab on bone marrow 
eosinophils, mast cells and their precursors 
4) 
To assess the long-term safety and efficacy of sc benralizumab in 
reducing eosinophilia in subjects with HES 
5) 
To assess the pharmacokinetics of benralizumab and the 
development of ADA levels in HES 
6) 
To assess the efficacy of every 8 week dosing of benralizumab in 
HES 
 
2.3 
Exploratory Objectives  
 
Exploratory objectives will include 1) identification of predictors of response to 
benralizumab in subjects with HES and 2) assessment of the effects of eosinophil 
depletion on vaccine responsiveness and glucose homeostasis.  
 

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3 Study Design 
 
3.1 
Description of the Study Design  
 
This study will be a single center trial with 5 parts: 1) randomized, double-blind sc 
benralizumab vs. placebo every 4 weeks for 12 weeks, 2) open-label sc benralizumab 
every 4 weeks for 12-36 weeks, 3) open-label sc benralizumab extension for 
benralizumab responders, with doses every 4 weeks for 6 months, 4) open label 
substudy of sc benralizumab administration every 8 weeks in complete responders, and 
5) open-label extension of self-administered sc benralizumab using an autoinjector for 
subjects with a sustained and complete response, for a minimum of 2 years. Eligible 
subjects enrolled on study protocol 94-I-0079 (Activation and function of eosinophils in 
conditions with blood or tissue eosinophilia) or referred from outside physicians for 
evaluation of hypereosinophilia will be invited to participate. A maximum of 20 subjects 
will be enrolled.  
 
Baseline evaluation will include a complete history and physical examination, routine 
laboratory testing and assessment of end organ involvement (see Appendix A). 
Baseline research studies will include bone marrow aspirate and biopsy to assess 
eosinophil and mast cell numbers and activation, storage of peripheral blood 
mononuclear cells (PBMC) for future studies, assessment of baseline eosinophil 
activation and T/B/NK subsets by flow cytometry, and measurement of serum markers 
of eosinophil and mast cell activation. Potential predictors of response to benralizumab, 
including eosinophil surface and soluble IL-5Ra levels and plasma cytokine profiles, will 
also be explored.  
 
Part 1: Benralizumab (30 mg) or placebo will be administered sc every 4 weeks for 3 
doses (at weeks 0, 4 and 8). Eosinophil counts will be blinded during this time and 
background HES therapy will not be tapered. 
 
Part 2: Following the placebo-controlled portion of the trial, all subjects will receive an sc 
injection of benralizumab at weeks 12, 16, and 20 . Eosinophil counts will be unblinded 
after the first week of open-label therapy (study week 13) and HES therapy may be 
tapered if clinically indicated. Subjects demonstrating a response at the 24 week visit  
(eosinophil count <1000/µL and stable or improved clinical symptoms without an 
increase in background HES therapy) will receive additional 30 mg sc injections every 4 
weeks for 6 doses. Non-responders will receive no further doses of benralizumab. 
 
Subjects will be followed daily for 3 days following the initial dose of benralizumab or 
placebo, weekly for 4 weeks and every 2 weeks for 8 weeks. At 12 weeks, the baseline 
evaluation will be repeated prior to initiation of open-label benralizumab therapy. After 
the first dose of open-label benralizumab, subjects will again be followed for 3 days, 
weekly for 4 weeks and every 2 weeks for 8 weeks to ensure subject safety. 
Subsequent visits will occur every 4 weeks for responders and every 12 weeks for non-

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responders for the remainder of the trial. Assessment at followup visits other than the 
baseline, 12, 24, 36 and 48 week visits, will be limited to a targeted history and physical 
examination, including AE/SAE evaluation, routine laboratory testing and collection of 
blood and urine samples for research studies. In order to assess the potential impact of 
eosinophil depletion on vaccine responses, all eligible subjects will receive Tdap 
vaccine at the 22 week visit with assessment of anti-tetanus antibody titers 6 weeks 
later. 
 
Part 3: For subjects who complete the study and for whom benralizumab provides 
sustained clinical benefit, drug (accessorized prefilled syringe (APFS) may be provided 
on an open-label extension of benralizumab administered every 4 weeks for responders 
until regulatory approval and commercial availability of the marketed drug to prescribing 
physicians (for HES) or until AstraZeneca ceases development of the drug for this 
indication. This open-label extension may involve administration of sc benralizumab by 
local providers in the setting of the COVID19 epidemic due to the increased risk 
associated with travel to the NIH.  
 
Part 4: For subjects with a sustained and complete response to benralizumab on the 
open-label extension for a minimum of 2 years, the dosing interval may be increased to 
every 8 weeks (the FDA-approved dosing interval for severe eosinophilic asthma).  
 
Part 5: Subjects participating in part 3 or part 4 with a sustained and complete response 
to benralizumab for a minimum of 2 years will be transitioned to the single-dose 
autoinjector (FASENRA PENTM) until regulatory approval and commercial availability of 
the marketed drug to prescribing physicians (for HES) or until AstraZeneca ceases 
development of the drug for this indication.  
 
3.2 
Study Endpoints 
 
3.2.1 Primary Endpoint 
The primary endpoint is a 50% reduction in peripheral blood eosinophilia on stable 
background therapy at 12 weeks post-initiation of study. 
 
3.2.2 Secondary Endpoints  
Secondary endpoints include: 1) Reduction in AEC at 12 weeks, 2) Frequency and 
severity of AEs, 3) Reduction in signs and symptoms of HES, 4) Tissue eosinophilia, 5) 
Numbers of eosinophils, mast cells and their precursors in bone marrow, 6) Levels of 
markers of eosinophil and mast cell activation,  7) Eosinophil count and background 
HES therapy at the 48 week visit, 8) PK and ADA levels, 8) Eosinophil count after 24 
weeks of every 8 week dosing. 

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3.2.3 Exploratory Endpoints  
Exploratory endpoints include 1) correlation between IL5 receptor levels and reduction 
in peripheral blood eosinophilia at 1, 4 and 12 weeks, 2) the rise in anti-tetanus 
antibodies at 6 weeks post-immunization and 3) the change in weight and HgbA1c 
levels after 12 and 24 weeks of benralizumab. 
 
4 Study Population 
 
4.1 
Rationale for Subject Selection  
 
Adult subjects aged 18-75 with PDGFRA-negative HES who are are symptomatic with 
AEC >1000/µL on stable HES therapy for at least 1 month will be selected for this study. 
Because benralizumab is of unknown benefit in this patient population, subjects with 
life-threatening disease will be excluded. Subjects with imatinib-sensitive mutations, 
including FIP1L1/PDGFRA, will also be excluded even if they are resistant to or 
intolerant of imatinib, since therapeutic alternatives targeting these mutations are 
currently available and would be the preferred treatment. 
 
4.2 
Recruitment Plan  
 
Subjects will be recruited from patients referred from outside physicians for evaluation 
of hypereosinophilia and those already evaluated on protocol 94-I-0079 (“Eosinophil 
activation and function in parasitic infections and other conditions with increased tissue 
or blood eosinophilia in humans”). In addition, a small number of physicians who study 
this disorder will be contacted directly and informed of this study.  
 
4.3 
Subject Inclusion Criteria 
 
A subject will be eligible for participation in the study only if all of the following criteria 
apply: 
 
1) Male or female subject ≥18 and ≤75 years of age at screening.  
 
2) A female subject is eligible for this study only if she is not pregnant or breast-
feeding and one of the following: 
 
a. Of childbearing potential but agrees to practice effective contraception, 
as determined by the PI, or abstinence throughout the study and for 3 
months after administration of the last dose of investigational study 
drug 

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b. Of non-child-bearing potential 
 
Females of non-child-bearing potential are defined as females with functioning 
ovaries with a documented history of tubal ligation or hysterectomy or females 
who are post-menopausal, as defined by 12 months of spontaneous amenorrhea 
with an appropriate clinical profile, e.g. age appropriate, >45 years, in the 
absence of hormone replacement therapy. In questionable cases, a blood 
sample for follicle stimulating hormone and estradiol will be obtained to confirm 
child-bearing potential.  
 
Acceptable methods of contraception may include a male partner who is sterile 
prior to the female subject’s entry into the study and is the sole sexual partner for 
the female subject; or 2 or more of the following: 1) implants of levonorgestrel; 2) 
injectable progestogen, 3) an intrauterine device with a documented failure rate 
of <1%; 4) double barrier methods including diaphragm or condom with a 
spermicide. 
 
3) A male subject is eligible for this study only if he is one of the following: 
 
 
a. Surgically sterile 
b. Agrees to practice effective contraception (see above) or abstinence 
throughout the study and for 3 months after the last administration of the 
investigational study drug 
 
4) Documented diagnosis of HES (history of persistent eosinophilia >1500/µL 
without secondary cause and evidence of end organ manifestations 
attributable to the eosinophilia) 
 
5) Signs or symptoms of HES and AEC >1000/µL on stable HES therapy for ≥ 1 
month at the time of enrollment 
 
6) Participation in protocol 94-I-0079 (Activation and function of eosinophils in 
conditions with blood or tissue eosinophilia) 
 
7) Agrees to storage of samples for study 
 
Participation of Women:   
Contraception: The effects of benralizumab on the developing human fetus 
are unknown.  For this reason, men and women of childbearing potential must 
agree to use adequate contraception (hormonal or barrier method of birth 
control; abstinence) prior to study entry and for the duration of study 
participation.  Females of childbearing-age must have a pregnancy test result 
prior to receiving benralizumab.  During the course of the study, if a woman 
becomes pregnant or suspects she is pregnant, she should inform the study 
staff and her primary care physician immediately.  
 

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In the event of pregnancy, the status of the subject and the overall risks and 
benefits to BOTH mother and fetus with regard to continuing or discontinuing 
the study agent will be assessed by the PI.  The PI will review data that may 
be available through the manufacturer and that may be in any pregnancy 
registry.  The IRB will also be notified per steps outlined in this protocol. 
 
The investigational drug may be continued if the overall risk and benefit 
assessment for BOTH the mother and the fetus favors continuation, AND if 
the subject and the study team agree to this course of action, after a 
documented informed consent discussion. The IRB and the clinical safety 
office/sponsor medical monitor will be notified as to the outcome of such a 
discussion and the subject’s decision. 
 
• The pregnant subject will be enrolled in the AstraZeneca pregnancy 
registry.  
• Blood testing will be limited to safety labs, blood draw volumes will be 
minimized per PI discretion to avoid exacerbation of 
hemodilution/anemia related to pregnancy. 
• The PI will provide the subject with pertinent information to provide to 
their pregnancy care provider, and will be counseled to consult with a 
Maternal Fetal Medicine specialist [High Risk Obstetric provider] due to 
the underlying condition as well as the ongoing study drug exposure. 
• All procedures, other than those required for clinical reasons, will be 
deferred until after the pregnancy. 
• The subject will be considered enrolled through at least the end of the 
pregnancy so as to facilitate collection of outcome data. 
 
4.4 
Subject Exclusion Criteria 
 
A subject will be excluded from participation in the study if any of the following criteria 
apply at the time of enrollment: 
 
1) Subjects with life-threatening or other serious illness or clinical manifestation 
of HES deemed inappropriate for inclusion in study per the principal investigator, 
including but not restricted to severe cardiac involvement and prior 
thromboembolic disease. 
 
2) Human immunodeficiency virus (HIV) or other known immunodeficiency 
 
3) Positive hepatitis B surface antigen, or hepatitis C virus antibody serology, or a 
positive medical history for hepatitis B or C. Patients with a history of hepatitis B 
vaccination without history of hepatitis B are allowed to enroll 
 
 4) Presence of FIP1L1/PDGFRA or another known imatinib-sensitive mutation  
 

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5) Diagnosis of systemic mastocytosis or serum tryptase level >40 ng/mL 
 
6) Known lymphoma, hematological malignancy, advanced and metastatic solid 
tumors and/or subjects who are under chemotherapy, radiotherapy or interleukin 
2 treatment 
 
7) Known history of allergic or anaphylactic reaction to previous antibody therapy, 
including intravenous immunoglobulin and licensed or experimental monoclonal 
antibodies. 
 
8) A helminth parasitic infection diagnosed within 24 weeks prior to the date 
informed consent is obtained  
 
9) Acute bacterial or viral infection (subjects may be enrolled once the acute 
infection has resolved)  
 
10) Receipt of intravenous immunoglobulin (IVIG) within 30 days prior to the date 
informed consent is obtained 
 
11) Receipt of any marketed (eg omalizumab) or investigational biologic within 4 
months or 5 half-lives prior to the date informed consent is obtained, whichever is 
longer 
 
12) Receipt of live attenuated vaccines 30 days prior to the date of randomization 
 
13) Receipt of inactive/killed vaccinations (e.g. inactive influenza) are allowed 
provided they are not administered within 1 week before/after any study visit 
 
14) Receipt of any investigational nonbiologic within 30 days or 5 half-lives prior 
to the date informed consent is obtained, whichever is longer 
15) History of alcohol or drug abuse within 12 months prior to the date informed 
consent is obtained 
 
16) Previous treatment with benralizumab  
 
 
Co-enrollment Guidelines: Co-enrollment in other trials is restricted, other than 
enrollment on observational studies or those evaluating the use of a licensed 
medication. Study staff should be notified of co-enrollment as it may require the 
approval of the Investigator.  
 
4.5 
Justification for Exclusion of Children  
 

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Because there are insufficient data regarding dosing or adverse events available in 
adults with HES to judge the potential risk in children, children are excluded from this 
study. 
 
5 Study Agent/Interventions  
 
5.1 
Disposition and Dispensation  
 
Benralizumab or placebo will be distributed via the NIH Central Pharmacy according to 
standard pharmacy procedures.  
 
5.1.1 Formulation, Packaging and Labeling  
 
Benralizumab Drug Product is a sterile liquid solution presented in an accessorized 
prefilled syringe (APFS) or single-dose autoinjector (FASENRA PENTM) for sc injection.  
Each syringe contains 30 mg of benralizumab in a 1.0 mL volume (nominal).  The Drug 
Product is formulated at 30 mg/mL in 20 mM histidine/histidine-HCl, 0.25 M trehalose 
dihydrate, and 0.006% (w/v) polysorbate 20, pH 6.0 (Table 1). 
 
Table 1 
Benralizumab composition 
Ingredient 
Concentration 
Unit formula per 30 mg 
syringe (nominal) 
Active ingredient 
Benralizumab 
30 mg/mL 
30 mg 
Other ingredients 
L-Histidine 
9 mM 
1.4 mg 
L-Histidine HCl 
monohydrate 
11mM 
2.3 mg 
Trehalose dihydrate 
0.25 M 
95 mg 
Polysorbate 20 
0.006% (w/v) 
0.06 mg 
 
During the double-blind period, placebo solution will be visually matched with 
benralizumab solution. Both benralizumab and placebo will be provided in an 
accessorized pre-filled syringe. 
Each accessorized pre-filled syringe will be individually labeled by the NIH pharmacy 
with the patient ID number, dosing instructions, recommended storage conditions, the 
name and address of the manufacturer, Investigational Use Statement (“Caution: New 

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Drug – Limited by Federal [USA] law to Investigational Use”) and that the agent should 
be kept out of reach of children. 
 
Drug may be administered at a collaborating site under an OHSRP-approved reliance 
agreement once the site is approved by the NIH IRB. In this case, the NIH pharmacy 
will provide the individually labeled syringes to the pharmacy at the collaborating site 
and documentation, including receipt date and condition, storage conditions, and date 
and time of administration, will be provided by the collaborating site to the NIH Central  
pharmacy.  
 
FASENRA PEN may be administrated by patients/caregivers during the open-label 
extension instead of benralizumab in an APFS. Patients/caregivers may inject 
FASENRA PEN after proper training in subcutaneous injection technique and 
observation of patient/caregiver administration by the PI or their delegate. 
Documentation of training and administration will be recorded in CRIMSON.  
 
Each FASENRA PEN carton will be individually labeled by the NIH pharmacy with the 
patient ID number, dosing instructions, recommended storage conditions, the name and 
address of the manufacturer, Investigational Use Statement (“Caution: New Drug – 
Limited by Federal [USA] law to Investigational Use”) and that the agent should be kept 
out of reach of children.   
 
5.2 
Study Agent Storage and Stability  
Benralizumab must be stored in the original outer container refrigerated at 2-8°C (36°F-
46°F), protected from the light, and must not be frozen.  
5.3 
Preparation, Administration, and Dosage of Study Agent 
5.3.1 Study Drug Administration 
 
Benralizumab (30 mg dose) or placebo APFS will be administered by SC injection by 
the principal investigator or qualified designee using aseptic technique via a 29-gauge 
0.5 inch needle over at least 5 seconds.   
It is advised that the site of injection be rotated such that the patient receives the study 
drug at a different anatomical site at each treatment visit. A suggested injection site 
rotation sequence is presented below (see Figure 2). The injection site must be 
documented at each treatment visit. If rotation of the site according to the recommended 
sequence is not possible, a reason for this must be given.  
Figure 2 
Injection sites and rotation scheme 

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Administration of the study drug will be rescheduled if the subject has an intercurrent 
illness that, in the opinion of the PI, may compromise the safety of the subject or if the 
subject reports a fever (≥38°C; ≥100.4°F) within 72 hours prior to planned administration 
of the study drug.  
The subject will be observed for a minimum of 30 minutes after administration of the 
study drug for the appearance of any acute drug reactions. Appropriate drugs, such as 
epinephrine and H1 and H2 antihistamines, corticosteroids, etc, and medical equipment 
to treat acute anaphylactic reactions must be immediately available, and study 
personnel must be trained to recognize and treat anaphylaxis.  
Anaphylaxis will be defined as serious reaction that is rapid in onset and may cause 
death. Anaphylaxis typically manifest as one of 3 clinical scenarios: 
1. 
The acute onset of a reaction (minutes to hours) with involvement of the skin, 
mucosal tissue or both and at least one of the following: a) respiratory 
compromise; b) or reduced blood pressure or symptoms of end-organ 
dysfunction; 
2. 
Two or more of the following that occur rapidly after exposure: involvement of 
the skin/mucosal tissue, respiratory compromise, reduced blood pressure or 
associated symptoms and/or persistent gastrointestinal symptoms; or  
3. 
Reduced blood pressure after exposure. 
In order to help understand the potential drug-relatedness of any acute reaction, a blood 
sample should be drawn during the event for additional ADA testing (if not already 
scheduled for this visit).  
Refer to the FASENRA PEN ‘Instructions for Use’ for more detailed instructions on the 
preparation and administration of FASENRA PEN (

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Appendix F: FASENRA PEN: Instructions for Use).  
5.3.2 Study Drug Dosing 
Population modelling of clinical efficacy endpoints (Asthma Exacerbation Rate (AER), 
Asthma Control Questionnaire (ACQ), and Forced Expiratory Volume in 1 second 
(FEV1)) from the interim analysis for the Phase 2 asthma study, MI-CP220, and 
stochastic simulations identified the optimal dose and regimen for the pivotal Phase 3 
studies with benralizumab in adult subjects with asthma as 30 mg every 4 weeks for 3 
doses then every 8 weeks thereafter.  This dosing regimen corresponds to the ED90 for 
AER and ACQ, and maintains a steady-state PK exposure close to EC90 levels for FEV1 
and ACQ.  With a steady-state PK exposure 50% higher than 20 mg every 8 weeks, the 
30 mg dose every 8 weeks is expected to reduce the impact of PK variability related to 
factors such as higher body weight. The incidence of ADA (especially high-titer ADA) 
and the impact on PKPD were dose-dependent with decreased incidence and impact at 
higher doses. However, the ADA response was not more frequent in those subjects with 
blood eosinophils ≥300 cells/μL (20.7%) as compared to those with blood eosinophils 
<300 cells/μL (21.7%).  Since doses higher than 20 mg are expected to reduce the 
impact of ADA without modifying the dose interval, and there are no identified safety 
risks that would warrant consideration of a lower dose, subjects will receive 30 mg every 
4 weeks for 3-12 doses depending on whether they receive drug or placebo during the 
first part of the study and whether they demonstrate a clinical and hematologic response 
at study week 24.  
 
Subjects who complete the study and for whom benralizumab appears to provide a 
sustained clinical benefit, may be eligible to receive drug under an open-label extension 
until regulatory approval and commercial availability of the marketed drug to prescribing 
physicians (for HES), or until AstraZeneca ceases development of benralizumab for this 
indication. Complete responders may be eligible to extend the dosing interval to every 8 
weeks after sustained and complete remission of eosinophilia for ≥2 years at the 
investigator’s discretion.  
5.4 
Study Product Accountability Procedures  
 
The site-designated pharmacist is responsible for investigational product accountability, 
reconciliation and record maintenance. In accordance with all applicable regulatory 
requirements, the designated site pharmacist must maintain investigational product 
accountability records throughout the course of the study. The person(s) will document 
the amount of investigational product received from AstraZeneca and the amount 
administered to study subjects. At the end of the study, all unused supplies will be  
disposed of or destroyed per the policies of the sponsor. 
 
Upon receiving investigational product, the pharmacist will sign a Drug Receipt Form 
that will specify supply or lot numbers, expiration date, quantity shipped/delivered, and 
the date of receipt. All investigational products received, dispensed, destroyed or 

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returned will be recorded on a Drug Accountability Form. At the end of the study, 
reconciliation must be made between drug received, dispensed, returned and 
destroyed, and all discrepancies must be accounted for.  
 
For drug sent to outside physicians during the COVID19 epidemic and FASENRA PENs 
provided to study subjects, receipt, maintenance of cold chain (refrigerator temperature 
log) and administration will be confirmed by the study team and the pharmacy will be 
notified of any deviations. 
 
5.5 
Concomitant Medications and Procedures  
 
All concomitant prescription medications taken during study participation will be 
recorded in CRIMSON. For this protocol, a prescription medication is defined as a 
medication that can be prescribed only by a properly authorized/licensed clinician.  
Medications to be reported in CRIMSON are concomitant prescription medications, 
over-the-counter medications and non-prescription medications taken at the time of 
adverse events (all grades). 
 
5.6 
Prohibited Medications and Procedures  
 
HES medications, including but not limited to prednisone, will be allowed during the trial, 
but must be maintained at a constant dose beginning 1 month prior to enrollment until 
completion of the 12 week time point (primary endpoint assessment). Tapering or 
discontinuation of HES medications during this time will be permitted only in the event of 
drug toxicity.  
 
Treatment with the following agents will not be permitted unless discussed with and 
approved by the principal investigator: 
1) Systemic immunosuppressive medications other than HES medications initiated 
prior to enrollment 
2) Xolair or other monoclonal antibodies 
3) Investigational agents 
4) Non-drug therapies (i.e. herbal products, alternative therapies)  
 
6 Study Schedule 
 
All study assessments/procedures required for each study visit are summarized in 
Appendix B – Schedule of Procedures/Evaluations.  “Windows” for the study time points 
are as follows:  “Days” ± 2 days; “Weeks” ± 4 days, unless otherwise specified in 
section 6.5.  The study window in the instance of the open-label extension of 

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benralizumab injection is to occur every 28 days +/- 7 days (since the previous 
injection).   Blood volumes are given in Appendix C.  
 
6.1 
Screening  
 
Potential subjects will undergo screening assessments as part of protocol 94-I-0079. At 
a minimum, the following procedures will be performed within the month prior to 
enrollment: 
 
• Complete medical history, including year of HES diagnosis, clinical evidence 
that led to the diagnosis of HES and prior/current HES therapies  
• Physical examination 
• Complete blood count and routine chemistries 
• Serum tryptase level 
• HIV 1/2 serology 
• Hepatitis B and C serology 
• FIP1L1/PDGFRA testing (if results of prior testing at NIH are not available) 
• Serum or urine pregnancy test (for women of childbearing potential) 
• Additional testing as clinically indicated to assess end organ manifestations  
 
Those subjects who meet the eligibility criteria (Section 4.3) will be offered enrollment in 
the study. 
 
6.2 
Enrollment/Baseline  
 
Signed informed consent will be obtained prior to any study procedures being 
performed. Baseline studies will be performed no more than 14 days prior to study drug 
administration and will include: 
 
• Complete history and physical examination 
• Vital signs, including weight  
• CBC with differential 
• Routine laboratory testing, including electrolytes, liver panel, mineral panel, LDH, 
CPK, uric acid, troponin, ESR, CRP, PT/PTT and urinalysis  
• Serum tryptase, B12 and quantitative immunoglobulin levels (including IgE) 
• HgbA1c 
• Serum pregnancy testing in women of child-bearing potential 
• Whole blood flow cytometry to assess eosinophil activation, IL-5R expression, 
basophil numbers and activation, T/B/NK cell subsets 
• ECG 
• Echocardiogram 
• Pulmonary function testing including spirometry with bronchodilator response, 
evaluation of lung volumes and diffusion capacity 

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• Additional clinical testing as determined by pattern of clinical involvement 
• Tissue biopsies of affected organs (where possible) 
• Bone marrow aspirate and biopsy, including  
o quantification of eosinophils, mast cells, and their precursors 
o assessment of mast cell activation status (CD69 and CD63 surface 
expression) 
o assessment of IL-5R expression on eosinophils, basophils and their 
precursors 
o viable storage of bone marrow mononuclear cells for future studies 
• T and B cell receptor rearrangement studies 
• Collection of 60 cc whole blood for isolation and storage of plasma and PBMC for 
research studies 
• Collection of serum, plasma and urine for immunologic analyses 
• Measurement of benralizumab and anti-benralizumab antibody levels  
 
6.3 
Randomization and Blinding 
 
The subjects, the investigators, and all who are involved in the evaluation of the study 
subjects including study monitors and central laboratory personnel are blinded to a 
subject’s treatment assignment until all subjects have completed the week 13 visit. The 
NIH research pharmacist is identified as the unblinded third party who will be in charge 
of treatment assignment, maintaining study supplies/inventory list, and preparing the 
blinded study medication for each subject. The NIH research pharmacist will be 
independent of any study assessments. To maintain blinding, any discussion of the 
treatment assignment between the clinicians and the pharmacy staff is prohibited until 
the study is unblinded.  
Subjects will be assigned a screening number after completion of the eligibility checklist 
for enrollment in the study in CRIMSON. The study statistician or NIH research 
pharmacist will generate the randomization codes.  These codes will be maintained by 
the NIH research pharmacist. To reduce the potential for participant dropouts during the 
period between enrollment and initial dosing of the study agent, randomization will be 
defined to occur on the day that the first dose of study drug is administered. A study 
allocation number (1 through 20) will be assigned at this time. 
 
Because benralizumab (but not placebo) is expected to decrease peripheral and bone 
marrow eosinophil counts, the results of white blood cell count, peripheral eosinophil 
count, lymphocyte phenotyping, and bone marrow  aspirate and biopsy collected after 
the initial dose of benralizumab or placebo until week 13 of study treatment will be 
blinded to the study team and subjects until all subjects have completed week 13 of the 
study. Results of blood tests performed after this time (week 13 until the end of the 
study) will not be blinded since all subjects will be receiving benralizumab and 
knowledge of the results would not allow the study team to determine whether the 
subject had received benralizumab or placebo during the double-blind portion of the 
study. The NIH Clinical Research Information System (CRIS) by which laboratory 

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results are reported does not permit blinding of selected portions of the complete blood 
count and differential. A qualified NIH pathologist will monitor, in real time on a day to 
day basis, the results of the complete blood cell count and differential (including 
peripheral eosinophil count) during this period and will review the results of the bone 
marrow performed at 12 weeks. The physician who monitors these results will not be 
involved in the evaluation of study subjects or in making any study assessments. The 
NIH physician monitoring the results will notify the study team of critical or abnormal 
values (for example, low absolute neutrophil counts or abnormal hemoglobin or platelet 
values), but this will not result in unblinding of the randomization unless the absolute 
eosinophil count is revealed, intentionally (if medically indicated) or unintentionally.  
Subjects will be instructed to inform outside physicians that they are participating in this 
study and should not be informed of the results of eosinophil counts performed at an 
outside facility during the first 13 weeks of the study unless withholding this information 
compromises their medical care. The outside physician will also be contacted by the 
study team regarding the protocol requirements. Results or reports received from 
outside laboratories or physicians that could lead to unblinding of the study team will be 
handled by a study coordinator designated to fulfill this role. This study coordinator will 
not be involved in decisions pertaining to the medical management of the study subjects 
and will redact information that could inadvertently lead to unblinding of the study team.  
 
6.3.1 Maintenance of Safety in the Face of Blinding 
 
Clinical management of subjects with HES is typically guided by a combination of signs 
and symptoms and the peripheral absolute eosinophil count (AEC). Changes in AEC in 
the absence of clinical manifestations would not provoke a change in therapy unless the 
change were dramatic (change >2 fold or AEC >5000/µL) and confirmed with a second 
CBC. In order to ensure safety of the participants, the NIH physician monitoring the 
counts will be instructed to notify the PI if a change of this magnitude occurs. As 
discussed above, the PI will be informed of all abnormal values in CBC parameters 
other than the AEC. Although we do not anticipate bone marrow changes at week 12 
that would lead to changes in therapy, should abnormalities be detected that require 
therapeutic intervention, the NIH pathologist will notify the PI.  
 
6.3.2 Implications of Blinding on Safety Reporting 
 
As described above (Section 6.3), the study team will be blinded to the complete blood 
count and differential during the placebo-controlled portion of the study. It is anticipated 
that, during this time, some blinded laboratory values will meet the threshold of an AE. 
For laboratory tests other than the absolute eosinophil count, the NIH pathologist 
monitoring the tests in real time will inform the PI of critical or abnormal results, and 
these will be recorded as described in Section 11.14.4. For absolute eosinophil counts 
that fall outside the normal range but do not reach the threshold for breaking the blind, 

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reporting will be deferred until the blind has been lifted. Reporting of bone marrow 
abnormalities at week 12 will also be deferred until the blind is lifted except in cases 
where therapeutic intervention is indicated on the basis of the findings. 
 
SAEs, and AEs of grade 3 or greater will continue to be forwarded to and assessed by 
the PI, and will be reported in real time, as will any events that are part of a concerning 
clinical picture, or that present a scenario requiring intervention. 
 
6.4 
Study Phase 
 
Within 14 days of completion of baseline studies, subjects will begin treatment with 
study drug.  
 
Benralizumab (30 mg) or placebo will be administered sc (as described in Section 5.4) 
in the OP11 clinic, the 5 SW Day Hospital, or the 5 SE inpatient nursing unit. Vital signs 
will be checked immediately prior to and at 30 minutes after the injection.  
 
Subjects will be admitted to the inpatient ward for overnight observation following the 
first dose of study drug to facilitate monitoring of AEs. The inpatient stay may be 
extended if clinically indicated. Subjects will be seen daily (in OP11 or on the inpatient 
ward) for 3 days following the first dose of study drug, and then at weeks 1, 2, 3, 4, 6, 8, 
10, and 12. Re-dosing of benralizumab or placebo will occur every 4 weeks for a total of 
3 doses (at weeks 0, 4, and 8). Subjects who develop AEs after the first dose of study 
drug may be monitored during subsequent doses at the discretion of the investigator.  
Subjects who develop grade 3 or greater AEs that are considered by the investigator to 
be possibly, probably, or definitely related to study drug will promptly, and prior to 
subsequent dosing, be discussed in writing or verbally with a Sponsor Medical Monitor 
in the Clinical Safety Office.  
 
At the 12 week visit, all subjects will receive benralizumab (30 mg) sc. Since the 
subjects who received placebo during the first 12 weeks of the study will be receiving 
their first dose of benralizumab at this visit, all subjects will be admitted to the inpatient 
ward for overnight observation following the first dose of study drug and followed daily 
(in OP11 or on the inpatient ward) for 3 days, every week for 4 weeks and and then at 
weeks 1, 2, 3, 4, 6, 8, 10, and 12, 13, 14, and 15. Re-dosing of open-label benralizumab 
will occur every 4 weeks for a total of 3 doses (at weeks 12, 16 and 20), after which 
subjects demonstrating a clinical response will continue to receive additional doses 
every 4 weeks for one year. Non-responders will receive no further doses of 
benralizumab. Subsequent visits will occur at 4-week intervals for responders and at 
12-week intervals for non-responders for the duration of the study. After a minimum of 2 
years of complete response on the open-label extension, the dosing interval (and visits) 
may be increased to every 8 weeks (the FDA-approved dosing interval for severe 
eosinophilic asthma).  
 

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Subjects who have have a sustained and complete reduction in eosinophilia and stable 
clinical signs and symptoms for ≥2 years and are on a stable dosing interval of 
benralizumab may be eligible to self-administer study drug monthly or every other 
month using the FASENRA PEN autoinjector. Subjects who self-administer 
benralizumab will have a CBC drawn monthly at NIH or a local laboratory. They will 
return to NIH for routine followup visits every 6 months. An interim visit will be 
scheduled if they develop clinical symptoms of HES and/or their AEC rises above 
100/µL. 
 
Women of childbearing potential will undergo serum pregnancy testing prior to each 
administration of benralizumab.  
 
At the 22 week visit, subjects who have not received tetanus immunization in the prior 5 
years and have no contraindication to Tdap immunization will receive Tdap vaccine. 
The vaccine will be administered by a study nurse in the OP11 clinic according to 
standard clinical protocol (0.5 mL intramuscularly).  
 
6.5 
Follow-up  
 
Follow up visits will be scheduled daily for 3 days, every 7 days (+/- 2 days) for 4 weeks, 
every 14 days (+/- 3 days) for 8 weeks after the initial dose of benralizumab vs. placebo 
and after the first open-label dose of benralizumab. Subsequent visits will be scheduled 
every 4 weeks (+/- 4 days, up to Week 48) for the remainder of the study for responders 
and at 12 weeks intervals for non-responders. Subjects going on to the open-label 
extension (after Week 48) will be scheduled every 4 weeks post last study drug 
administration (+/- 7 days). After a minimum of 2 years in complete remission, subjects 
may be scheduled every 8 weeks post last study drug administration (+/- 7 days) and/or 
every 6 months for subjects self-administering benralizumab using the auto-injector 
(FASENRA PEN).  
 
The following studies will be performed at every followup visit until (and including) week 
48: 
 
• Vital signs, including weight 
• Targeted history and physical examination 
• AE/SAE assessment 
• CBC with differential  
• Routine chemistries (electrolyte, hepatic and mineral panels) 
• LDH 
• Creatine Kinase (CPK) 
• Serum tryptase level 
• Urinalysis 
• Collection of urine (only up to Week 48), serum and plasma for research studies 
 

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The following additional studies will be performed at the monthly visits until (and 
including) week 48, prior to administration of study drug: 
 
• ESR, CRP 
• Total Protein 
• Uric Acid 
• Serum pregnancy testing for women of child-bearing potential 
• Serum for PK and ADA studies 
 
 
The following studies will be performed at monthly/bimonthly/every 6 month visits after 
week 48: 
 
• Vital signs, including weight 
• Targeted history and physical examination 
• AE/SAE assessment 
• CBC with differential  
• Routine chemistries (electrolyte, hepatic and mineral panels; only at NIH visits) 
• Serum pregnancy testing for women of child-bearing potential 
 
NOTE: if the subject is receiving drug under an OHSRP-approved reliance agreement 
or by an outside physician during the COVID19 epidemic, these studies may be 
performed at the outside site. Subjects receiving drug every 8 weeks will continue to 
have monthly CBC performed at the NIH or an outside site for 24 weeks after the dosing 
interval increase.   
 
The following additional studies will be performed at the 12, 24, 36 and 48 week 
followup visits, and every 4-6 months on the open-label extension except as indicated: 
 
• PT/PTT (week 12 only) 
• Troponin (yearly after week 48) 
• ESR, CRP (yearly after week 48) 
• Total Protein (yearly after week 48) 
• Uric Acid (yearly after week 48) 
• Serum B12 (yearly after week 48)  
• Quantitative immunoglobulin levels (including IgE)  
• HbA1c (12 and 24 weeks only) 
• ECG (yearly after week 96 unless clinically indicated) 
• Echocardiogram (yearly after week 96 unless clinically indicated)  
• Pulmonary function testing including spirometry with response, evaluation of lung 
volumes and diffusion capacity bronchodilator (yearly after week 96 unless 
clinically indicated)  
• Additional clinical testing as determined by pattern of clinical involvement 
• Tissue biopsies of affected organs (if clinically indicated) 
• Bone marrow aspirate and biopsy (at 12 weeks only), including  

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o quantification of eosinophils, mast cells, and their precursors 
o assessment of mast cell activation status (CD69 and CD63 surface 
expression) 
o assessment of IL-5R expression on eosinophils, basophils and their 
precursors 
o viable storage of bone marrow mononuclear cells for future studies 
• Collection of 60 cc whole blood for isolation and storage of plasma and PBMC for 
research studies (yearly after week 96) 
• Collection of serum for immunologic analyses  
• Collection of urine for immunologic analyses (until and including week 48)  
• Whole blood flow for IL-5 receptor expression, enumeration of basophil numbers 
and activation (at weeks 0, 12, 24, 36, 48 only) 
• Assessment of T/B/NK cell subsets  
• T and B cell receptor rearrangements (weeks 12 and 48 only) 
 
Tetanus antibody titers will be assessed at 22 (pre-immunization) and 28 weeks 
(post-immunization). 
 
6.6 
Final Study Visit/Early Termination Visit 
 
The final study visit will occur 48 weeks after the first dose on study drug (either 
benralizumab or placebo). The studies to be performed are listed in Section 6.5. 
 
Subjects who are not eligible to continue receiving benralizumab, who elect not to 
participate in the open-label extension, or who withdraw for any reason prior to 
completing the study will be asked to return for followup visits every 4 weeks until week 
12 (with a scheduled visit at week 12 included) and every 12 weeks therafter for the 
planned duration of their study participation.  
 
6.7 
Open-label Extension 
 
For subjects who complete the study and for whom benralizumab appears to provide 
sustained clinical benefit, drug may be provided on an open-label extension until 
regulatory approval and commercial availability of the marketed drug to prescribing 
physicians (for HES) or until AstraZeneca ceases development of the drug in HES.  
All subjects continuing to receive drug monthly on the open-label extension will be 
scheduled for followup visits and drug administration every 3 months at the NIH. 
Intervening monthly followup and drug administration will occur either at the NIH or at a 
collaborating site under an OHSRP-approved reliance agreement. All collaborating sites 
will submit a local context form and be approved by the NIH IRB prior to site initiation.  
 
Subjects who have a sustained and complete reduction in eosinophilia for ≥2 years may 
be eligible to extend the dosing interval to 8 weeks at the investigator’s discretion.  If at 
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and/or symptoms worsen, the dosing interval may be reduced to every 4 weeks for that 
subject for the duration of the study. Subjects will be asked to fill out weekly patient-
reported outcome questionnaires to assess pain, fatigue, dyspnea and gastrointestinal 
symptoms (PROMIS v1.0; http://www.healthmeasures.net) for 2-4 weeks prior to and 4 
months following the change to every 8 week dosing to assist in the objective 
determination of symptom worsening.  
 
Subjects who have a sustained and complete reduction in eosinophilia and stable 
clinical signs and symptoms for ≥2 years and are on a stable dosing interval of 
benralizumab may be eligible to self-administer benralizumab using the FASENRA PEN 
autoinjector. After subjects undergo training in the use of the autoinjector by 
credentialed OP8 or LPD nursing staff and are provided with FASENRA PEN 
Instructions for Use (see Appendix F), FASENRA PEN autoinjectors will be provided to 
the study subject in a cold transport box or sent by the NIH Pharmacy to the subject’s 
home. Subjects will be instructed to obtain monthly CBC (with results sent to the study 
team) and to contact the study team within 24 hours of each injection to report the date, 
time, and site of the injection as well as any adverse events. Followup visits will occur 
every 6 months unless clinical signs or symptoms develop or the AEC rises to >100/µL, 
in which case an interim visit will be arranged.  
 
6.8 
Recontact of Subjects After Trial Termination 
 
After study termination, subjects will be contacted yearly as part of the required study 
visits for Protocol #94-I-0079.  In settings where subjects request to withdraw consent 
for protocol #94-I-0079, they will be asked whether they would be willing to be re-
contacted in the future.    
 
7 Study Procedures/Evaluations 
 
7.1 
Clinical Evaluations 
 
7.1.1 History and Physical Examination 
A complete medical history and physical examination will be performed as part of the 
baseline evaluation. Subsequent clinical evaluations will focus on the assessment of 
new symptoms, signs or untoward medical events. Vital signs, including blood pressure, 
heart rate, and body temperature will be measured as part of all physical examinations, 
according to standard nursing practice. Tympanic measurements of body temperature 
will be performed.  
 
7.1.2 Symptom Questionnaire 
An HES symptom questionnaire will be administered at all study visits (see  

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Appendix E: HES Questionnaire) . Subjects will also be encouraged to notify the 
Investigators of any new signs or symptoms that develop between follow-up visits. 
Newly emergent or worsening symptoms, clinically significant physical examination 
findings, and laboratory abnormalities will be recorded and scored as AEs using the 
“Common Terminology Criteria for Adverse Events (CTCAE)” (v 4.0):  
http://ctep.cancer.gov/protocolDevelopment/electronic_applications/ctc.htm. 
As described above, subjects who elect to increase the dosing interval to every 8 weeks 
will fill out patient-reported outcome questionnaires to assess pain, fatigue, dyspnea 
and gastrointestinal symptoms (PROMIS v1.0; http://www.healthmeasures.net).  
7.1.3 End Organ Assessment 
ECG, echocardiography, and pulmonary function testing will be prior to initiation of 
benralizumab or placebo, after 12 weeks of therapy and at the end of study visit. 
Quantification of other end organ manifestations will be individualized and may include 
physical examination findings, laboratory testing (ex. serum aldolase for eosinophilic 
myositis, serum transaminase levels for eosinophilic hepatitis, urine cytology for 
eosinophilic cystitis), imaging (such as fibroscan for liver involvement, MRI with stir 
images for eosinophilic myositis/fasciitis), and/or other minimally-invasive tests. All end 
organ assessments will be performed at the NIH Clinical Center using standard 
protocols. 
 
7.2 
Laboratory Evaluations 
 
7.2.1 Routine laboratory testing 
 
Routine safety laboratory evaluations, including complete blood count with differential, 
routine chemistries and urinalysis, will be performed in the Department of Laboratory 
Medicine at the NIH Clinical Center or at outside laboratories. The study team will be 
blinded to the results of complete blood counts with differential and flow cytometry 
studies during the first 13 weeks of study drug administration until all subjects have 
completed the 13 week time point (as described in Section 6.3).  
 
7.2.2 Bone marrow biopsy and aspirate 
 
Bone marrow aspirates and biopsies from the iliac crest will be performed using 
standard sterile techniques prior to and at 12 weeks following the first dose of 
benralizumab. Local anesthesia will be obtained using lidocaine.   Each aspirate 
typically provides 2-3 ml of bone marrow.  Two to 10 aspirates will be obtained to 
assess bone marrow morphology and the effects of benralizumab on the numbers and 
activation status of eosinophils, neutrophils, mast cells and their precursors. The results 

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of the 12 week bone marrow examinations will be blinded until all subjects have 
completed week 13 of the study (as described in Section 6.3).  
 
7.2.3 Exploratory assessments  
 
Serum, plasma, whole blood and urine will be collected at various time points for 
assessment of eosinophil activation, cytokine/chemokine profile and other immunologic 
parameters as described in Appendix D: Research Studies.  
Serum will also be collected for assessment of antibodies to benralizumab (ADA) and 
benralizumab drug levels. After centrifugation, the serum will be divided into 2 aliquots 
of at least 1.5 mL each, frozen, and then stored at -20 ºC until shipped on dry ice to 
AstraZeneca for analysis. 
If tissue biopsies are obtained for clinical indications during benralizumab therapy and 
sufficient material is available, immunohistochemical staining for eosinophil granule 
protein deposition may be performed according to a standard protocol developed by the 
Laboratory of Pathology, NCI. 
 
8 Potential Risks and Benefits 
 
8.1 
Potential Risks 
 
8.1.1 Blood Drawing 
The potential risks of the needle stick for blood drawing include pain, fainting, infection 
and bruising, or a small hematoma. The bruising may last up to 72 hours. Any 
hematomas will be treated with local pressure. Infection from the needle puncture is 
rare, but if this does occur, appropriate treatment will be given.  The total blood drawn 
during the study is within the guidelines of the NIH Clinical Center. (See Appendix C for 
total blood draw volumes). 
 
8.1.2 Benralizumab 
 
Based on data from the clinical trials to date, the most common AEs that were more 
frequently seen in subjects receiving benralizumab (>2% increased incidence compared 
to placebo) were nasopharyngitis, upper respiratory tract infection, pharyngitis, injection 
site erythema, injection site reaction, pyrexia, arthralgia and myalgia. Although AEs 
related to rapid lowering of eosinophil, basophil or mast cell numbers are not 
anticipated, subjects will be monitored as outpatients daily for 3 days after the initial 
dose of benralizumab. Long-term theoretical risks related to depletion of eosinophils in 

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the bone marrow and tissues include diminished responses to immunization and 
alterations in glucose homeostasis. 
 
Two subjects in the current trial have developed urinary stones. In the first case, 
analysis was not performed. Consequently, it is possible that this was a uric acid stone 
due to eosinophil lysis by benralizumab. The second subject had a prior history of a 
calclium oxalate stone, 3 years prior to enrolling on the trial. Analysis of her stone 
revealed that it was a calcium oxalate stone and thus, unlikely to be related to study 
drug. Urinary stones have not been reported in any of the other clinical trials.  
 
Benralizumab has not been tested in women who are pregnant; therefore the risk to a 
developing fetus is unknown.  Pregnant women will be excluded from the trial and all 
women of child-bearing age will be required to undergo pregnancy testing prior to and 
during the study and to practice contraception for the duration of the trial and for 3 
months after the last administration of the study drug. In the event of pregnancy, the 
status of the subject and the overall risks and benefits to BOTH mother and fetus with 
regard to continuing or discontinuing the study agent will be assessed by the PI. The 
investigational drug may be continued if the overall risk and benefit assessment for 
BOTH the mother and the fetus favors continuation, AND if the subject and the study 
team agree to this course of action, after a documented informed consent discussion. 
 
Development of anti-drug antibodies (ADA) to benralizumab has been documented. 
Theoretical risks of developing ADA include decreased drug efficacy and 
hypersensitivity reactions (e.g. anaphylaxis or immune complex disease). 
Eosinophils are a prominent feature of the inflammatory response to helminthic parasitic 
infections, and the presence of infiltrating eosinophils has been circumstantially 
associated with a positive prognosis in certain solid tumors. Therefore, there is a 
theoretical risk that prolonged eosinophil depletion may diminish the ability to defend 
against helminthic parasites, or negatively impact the natural history of certain 
malignant tumors. Risk minimization measures include exclusion of patients with 
untreated parasitic infection and active or recent malignancy, in conjunction with the 
performance of routine pharmacovigilance activities. 
 
8.1.3 Tdap 
 
Any routine immunization can be associated with injection site reactions, allergic 
reactions and rarely, Guillain Barre syndrome.   The current Tdap vaccine on formulary 
at the Clinical Center is Boostrix (GlaxoSmithKline). Common solicited adverse events 
(≥15%) in adults (19 to 64 years of age) following administration of Boostrix were pain, 
redness, and swelling at the injection site, headache, fatigue, and gastrointestinal 
symptoms. The most common solicited adverse event (≥15%) in the elderly (65 years of 
age and older) was pain at the injection site. Detailed information can be found in the 
package insert 

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(https://www.gsksource.com/pharma/content/dam/GlaxoSmithKline/US/en/Prescribing_I
nformation/Boostrix/pdf/BOOSTRIX.PDFhttp://us.gsk.com/products/assets/us_boostrix.
pdf).   
  
8.1.4 Bone marrow biopsy 
 
Bone marrow aspirates and biopsies from the iliac crest will be performed using 
standard sterile techniques just prior to initiation of benralizumab treatment and after 12 
weeks of benralizumab therapy. Local anesthesia will be obtained using lidocaine.   
Each aspirate typically provides 2-3 ml of bone marrow.  Two to 10 aspirates will be 
obtained to assess bone marrow morphology and the effects of dexpramipexole on the 
numbers and activation status of eosinophils and their precursors.  
8.1.5 Tissue biopsy 
Patients with eosinophilic tissue involvement that is accessible (skin, gastrointestinal 
tract, lung or sinus) may undergo biopsies as part of standard of care. In this case, 1-2 
additional tissue samples may be obtained for research purposes. The risks of obtaining 
additional biopsies represent a minimal increase in risk over the risks of the clinically-
indicated procedure and include bleeding, scarring (skin), and rarely, perforation 
(gastrointestinal). 
 
8.1.6 Other research procedures 
Other procedures performed for research purposes include electrocardiogram, 
echocardiogram, pulmonary function testing and urine collection. These are associated 
with minimal (if any) risk.  
 
8.2 
Potential Benefits 
 
Individual participants in the study will benefit from a thorough medical evaluation. Since 
the effect of benralizumab on eosinophilia in HES is unknown, subjects may or may not 
benefit from the experimental therapy. In the event that a beneficial effect is found, a 
larger efficacy study will likely be performed that may benefit subjects with HES. Since 
Tdap is currently recommended for adults aged 18-65, subjects who have not been 
previously immunized with this vaccine will derive benefit from this procedure. Subjects 
will not be compensated for participation in this study, but will be reimbursed for their 
transportation costs as is permitted by the NIAID travel policy. 
 
9 Research Use of Stored Human Samples, Specimens or 
Data 
 
• Intended Use: Samples and data collected under this protocol may be used to 
study eosinophilic disorders. Genetic testing will be performed. Any other 

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research or experimental treatments will be done under this or other protocols for 
which separate signed informed consent documents will be obtained. 
• Storage:  Access to stored samples will be limited using either a locked room or 
a locked freezer.  Samples and data will be stored using codes assigned by the 
investigators.  Data will be kept in password-protected computers.  Only 
investigators will have access to the samples and data.  
• Tracking: Samples and data acquired during this study will be tracked using 
BioSpecimen Inventory (BSI).   
• Disposition at the Completion of the Protocol:  
• In the future, other investigators (both at NIH and outside) may wish to use 
these samples and/or data for research purposes. If the planned research 
falls within the category of “human subjects research” on the part of the 
NIH researchers, IRB review and approval will be obtained. This includes 
the NIH researchers sending out coded and linked samples or data and 
getting results that they can link back to their subjects. 
• At the completion of the protocol (termination), samples and data will 
either be destroyed, or after IRB approval, transferred to another existing 
protocol.  
• Reporting the Loss or Destruction of Samples/Specimens/Data to the IRB: 
• Any loss or unanticipated destruction of samples (for example, due to 
freezer malfunction) or data (for example, misplacing a printout of data 
with identifiers) that meets the definition of a reportable event and/or 
compromises the scientific integrity of the data collected for the study, will 
be reported to the NIH IRB. 
• Additionally, subjects may decide at any point not to have their samples 
stored.  In this case, the principal investigator will destroy all known 
remaining samples and report what was done to both the subject and to 
the IRB.  This decision will not affect the subject’s participation in this 
protocol or any other protocols at NIH.  
10 Remuneration Plan for Subjects  
 
Subjects will not be remunerated for participation in this study. 
 
11 Assessment of Safety 
11.1 
Definitions 
The NIAID Clinical Safety Office (CSO) is responsible for sponsor safety oversight of 
this study, and the definitions below comply with CSO requirements. 
 
Adverse Event (AE) 
An adverse event is any untoward or unfavorable medical occurrence in a human 
subject, including any abnormal sign (e.g., abnormal physical exam or laboratory 

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finding), symptom, or disease, temporally associated with the subject’s participation in 
the research, whether or not considered related to the research. 
 
Adverse Reaction (AR) 
An adverse reaction is an adverse event that is caused by an investigational agent 
(drug or biologic). 
 
Suspected Adverse Reaction (SAR) 
An adverse event for which there is a reasonable possibility that the investigational 
agent caused the adverse event. ‘Reasonable possibility’ means that there is evidence 
to suggest a causal relationship between the drug and the adverse event. A suspected 
adverse reaction implies a lesser degree of certainty about causality than adverse 
reaction which implies a high degree of certainty. 
 
Serious Adverse Event (SAE) 
A Serious Adverse Event is an AE that results in one or more of the following outcomes: 
 
• death 
• a life threatening (i.e., an immediate threat to life) event 
• an inpatient hospitalization or prolongation of an existing hospitalization 
• a persistent or significant incapacity or substantial disruption of the ability to conduct 
normal life functions 
• a congenital anomaly/birth defect 
• a medically important event* 
 
* Medical and scientific judgment should be exercised in deciding whether expedited 
reporting is appropriate in other situations, such as important medical events that may 
not be immediately life threatening or result in death or hospitalization but they may 
jeopardize the subject or may require intervention to prevent one of the other 
outcomes listed above.  
 
Unexpected Adverse Event 
An AE is unexpected if it is not listed in the Investigator’s Brochure or Package Insert 
(for marketed products) or is not listed at the specificity or severity that has been 
observed.  It is the responsibility of the IND Sponsor to make this determination. 
 
Serious and Unexpected Suspected Adverse Reaction (SUSAR) 
A SUSAR is a Suspected Adverse Reaction that is both Serious and Unexpected.   
 
Unanticipated Problem (UP) 
An Unanticipated Problem is any event, incident, experience, or outcome that is 
 
1.  unexpected in terms of nature, severity, or frequency in relation to 
a. the research risks that are described in the IRB-approved research protocol and 
informed consent document; Investigator’s Brochure or other study documents; 
and 

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b. the characteristics of the subject population being studied; and 
2. possibly, probably, or definitely related to participation in the research; and 
3. places subjects or others at a greater risk of harm (including physical, psychological, 
economic, or social harm) than was previously known or recognized. (Per the IND 
Sponsor, an AE with a serious outcome will be considered increased risk.) 
 
Serious Unanticipated Problem (UP) 
A UP that meets the definition of a Serious Adverse Event or compromises the safety, 
welfare or rights of subjects or others. 
 
Unanticipated Problem that is not an Adverse Event (UPnonAE) 
 
Unanticipated problem that is not an Adverse Event (UPnonAE): An unanticipated 
problem that does not fit the definition of an adverse event, but which may, in the 
opinion of the investigator, involve risk to the subject, affect others in the research 
study, or significantly impact the integrity of research data.  Such events would be 
considered a non-serious UP. For example, we will report occurrences of breaches of 
confidentiality, accidental destruction of study records, or unaccounted-for study drug 
 
Protocol Deviation: Any change, divergence, or departure from the IRB-approved 
research protocol. 
1. Major Deviations: Deviations from the IRB-approved protocol that have, or may 
have the potential to, negatively impact the rights, welfare, or safety of the 
subject, or to substantially negatively impact the scientific integrity or validity of 
the study. 
2. Minor Deviations: Deviations that do not have the potential to negatively impact 
the rights, safety, or welfare of subjects or others, or the scientific integrity or 
validity of the study. 
 
Non-compliance: Failure of investigator(s) to follow the applicable laws, regulations, or 
institutional policies governing the protection of human subjects in research, or the 
requirements or determinations of the IRB, whether intentional or not. 
1. Serious non-compliance: Non-compliance, whether intentional or not, that 
results in harm or otherwise materially compromises the rights, welfare and/or 
safety of the subject. Non-compliance that materially affects the scientific integrity 
or validity of the research may be considered serious non-compliance, even if it 
does not result in direct harm to research subjects. 
2. Continuing non-compliance: A pattern of recurring non-compliance that either 
has resulted, or, if continued, may result in harm to subjects or otherwise 
materially compromise the rights, welfare and/or safety of subjects, affect the 
scientific integrity of the study or validity of the results. The pattern may comprise 
repetition of the same non-compliant action(s), or different noncompliant events. 
Such non-compliance may be unintentional (e.g. due to lack of understanding, 

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knowledge, or commitment), or intentional (e.g. due to deliberate choice to ignore 
or compromise the requirements of any applicable regulation, organizational 
policy, or determination of the IRB). 
 
11.2 
Documenting, Recording and Reporting Adverse Events 
All AEs occurring from the time the informed consent is signed through the specified 1 
year study follow-up period will be documented, recorded, and reported.  
 
At each contact with the subject, information regarding AEs will be elicited by 
appropriate questioning and examinations and will be:  
• immediately documented in the subject’s medical record/source document,  
• recorded in CRIMSON and  
• reported as outlined below (e.g., IND Sponsor, Institutional Review Board [IRB], and 
Food and Drug Administration [FDA]).  
 
If a diagnosis is clinically evident (or subsequently determined), the diagnosis rather 
than the individual signs and symptoms or lab abnormalities will be recorded as the AE.  
 
A laboratory abnormality will not be reported as an adverse event if ALL of the following 
criteria are met:  
• It is no more than “Grade 1” or “Mild” per the protocol specified toxicity table (or 
investigator assessment if not listed on the table); AND  
• It does NOT require an intervention (e.g., discontinuation of treatment, dose 
reduction/delay, additional assessments, or treatment); AND  
• It is assessed by the PI as NOT related to the study agent(s); AND  
• It is assessed by the PI as NOT clinically significant (e.g., the abnormal value does 
NOT suggest a disease or organ toxicity)  
 
All abnormal laboratory findings will be reviewed on a routine bases by the PI to identify 
potential safety signals. An abnormal lab not included on the toxicity table should be 
assessed in a similar fashion to the criteria above. 
Blinded laboratories, other than absolute eosinophil counts, that meet criteria for AEs 
will be reported to the study team by the unblinded NIH pathologist and included in the 
subject’s medical record and will be reported as above. Reporting of absolute eosinophil 
counts during the placebo-controlled portion of the study and/or bone marrow 
abnormalities at week 12 that meet criteria for an AE will be deferred until the blind is 
lifted except as specified in Section 6.3. 
 
11.3 
Investigator Assessment of Adverse Events 
 
All AEs occurring from the time the informed consent is signed through the end of study 
visit will be documented, recorded, and reported. The Investigator will evaluate all AEs 
with respect to Seriousness (criteria listed above), Severity (intensity or grade), and 

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Causality (relationship to study agent and relationship to research) according to the 
following guidelines.  
 
11.3.1 Severity 
The “Common Terminology Criteria for Adverse Events (CTCAE)” (v 4.0):  
http://ctep.cancer.gov/protocolDevelopment/electronic_applications/ctc.htm  
 
11.3.2 Causality    
Causality (likelihood that the event is related to the study agent) will be 
assessed considering the factors listed under the following categories:  
 
 
Definitely Related    
• reasonable temporal relationship 
• follows a known response pattern 
• clear evidence to suggest a causal relationship 
• there is no alternative etiology 
 
Probably Related  
• reasonable temporal relationship 
• follows a suspected response pattern (based on similar agents) 
• no evidence of a more likely alternative etiology 
 
Possibly Related  
• reasonable temporal relationship 
• little evidence for a more likely alternative etiology 
 
Unlikely Related 
 
• does not have a reasonable temporal relationship  
OR 
• good evidence for a more likely alternative etiology 
 
Not Related 
 
• does not have a temporal relationship 
         
OR 
• definitely due to an alternative etiology 
 
Note:    
Other factors (e.g., dechallenge, rechallenge) should also be considered for 
each causality category when appropriate. Causality assessment is based on 
available information at the time of the assessment of the AE. The investigator 
may revise the causality assessment as additional information becomes 
available. 
 

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11.4 
Investigator Reporting Responsibilities to the Sponsor 
 
11.4.1 Adverse Events 
Line listings, frequency tables, and other summary AE data will be submitted to the IND 
Sponsor when needed for periodic safety assessments, review of IND annual reports, 
review of IND safety reports, and preparation of final study reports. 
 
11.4.2 Serious Adverse Events 
SAEs whether or not they are also UPs) must be reported on the Safety Expedited Report 
Form (SERF) and sent to the Sponsor Clinical Safety Office (CSO) by fax or e-mail 
attachment. Deaths and immediately life threatening SAEs must be reported within 1 
business day after the site becomes aware of the event. All other SAEs must be 
reported within 3 business days of site awareness.  
 
SPONSOR CLINICAL SAFETY OFFICE  
CONTACT INFORMATION: 
 
OCRPRO Clinical Safety Office 
5705 Industry Lane 
Frederick, MD 21704 
Phone 301-846-5301 
Fax 301-846-6224 
E-mail: rchspsafety@mail.nih.gov  
 
11.4.3 Unanticipated Problems 
Unanticipated Problems that are also adverse events must be reported to the CSO and 
sent by fax or e-mail attachment no later than 7 calendar days of site awareness of the 
event. UPs that are not AEs are not reported to the Sponsor CSO. 
 
Report all UPs that are also adverse events to the CSO on the NIH Problem Report 
Form. 
 
11.4.4 Pregnancy  
 
Pregnancy itself is not an AE. However, complications of pregnancies are AEs and may 
be SAEs.  Pertinent obstetrical information for all pregnancies will be reported to the 
CSO via fax or email within 3 business days from site awareness of the pregnancy.   
 
Pregnancy outcome data (e.g., delivery outcome, spontaneous or elective termination of 
the pregnancy) will be reported to the CSO within 3 business days of the site’s 
awareness. 
 
In the event of pregnancy, the following steps will be taken: 

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• The study drug may be discontinued 
• The subject will be advised to notify their obstetrician of the study agent exposure 
• The subject will be followed up for safety until delivery or termination of the 
pregnancy 
• The event will be reported to the DSMB and IRB 
 
 
 
11.5 
Investigator Reporting Responsibilities to the IRB and 
NIAID 
11.5.1 NIH IRB Reporting 
UPs, non-compliance, and other reportable events will be reported to the NIH IRB 
according to NIH Human Research Protections Program (HRPP) Policy 801. 
11.5.2 Reporting to the NIAID Clinical Director 
The principal investigator will report UPs, major protocol deviations, and deaths to the 
NIAID clinical director according to institutional timelines. 
 
11.6 
Investigator Reporting Responsibilities to the Drug 
Supplier 
 
As per their requirements, AEs, SAEs, pregnancy, and unanticipated problems reported 
to the sponsor (OCRPRO) will also be reported to the drug supplier (AstraZeneca) 
within the same time frames described in Section 11.4. 
 
11.7 
Follow-up of Adverse Events and Serious Adverse Events  
 
AEs that occur following enrollment of the subject (by signing the informed consent) are 
followed until the final outcome is known or until the end of the study follow-up period. 
 
SAEs that have not resolved by the end of the follow-up period are followed until final 
outcome is known. If it is not possible to obtain a final outcome for an SAE (e.g., the 
subject is lost to follow-up), the reason a final outcome could not be obtained will be 
recorded by the investigator within CRIMSON  and the SERF.  
 
SAEs that occur after the study follow-up period (last study visit) that are reported to 
and are assessed by the Investigator to be possibly, probably, or definitely related must 
be reported to the CSO, as described above. 
 

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11.8 
Sponsor’s Reporting Responsibilities 
 
Serious and unexpected suspected adverse reactions (SUSARs) as defined in 21 CFR 
312.32 and determined by the IND Sponsor will be reported to FDA and all participating 
Investigators as IND Safety Reports.  
 
The IND Sponsor will also submit an IND Annual Report of the progress of the 
investigation to the FDA as defined in 21 CFR 312.33.  
 
11.9 
Halting Rules for the Protocol  
 
Halting the study requires immediate discontinuation of study agent administered for all 
subjects and suspension of enrollment until a decision is made whether or not to 
continue study agent administration.   
 
 
The halting criteria (as determined by the site investigators) for an individual site 
include:  
• Two or more subjects experience the same or similar SAEs that are unexpected  
and are possibly, probably, or definitely related to the study agent  
OR 
• any safety issue that the site investigators determine should halt the study  
 
The IRB/EC, the IND Sponsor, the DSMB or the FDA may halt the study at any time 
following review of any safety concerns 
 
11.9.1 Reporting of Study Halting 
If a halting requirement is met, a description of the event(s) or safety issue must be 
reported by the PI within one business day to the Sponsor CSO, DSMB, and 
AstraZeneca by fax or email. The PI must also inform the IRB that a halting rule has 
been met.  
 
11.9.2 Resumption of a Halted Study 
The IND Sponsor, in collaboration with the PI and DSMB will determine if it is safe to 
resume the study. The IND Sponsor will notify the PI of this decision. The conditions for 
resumption of the study will be defined in this notification. The PI will notify the IRB and 
AstraZeneca of the decision to resume the study. 
11.10 
 Pausing Criteria for a Subject or Group 
 
The decision to suspend administration of the study agent(s) for a single subject or for 
all subjects in a specific group requires discontinuation of study agent administrated for 

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the study subject(s) or group until a decision is made whether or not to continue study 
agent administration.   
 
The pausing criteria for a single subject or for the subjects in a specific group in this 
study include:  
• A subject experiences an SAE or Grade 3 or greater AE that is unexpected (as 
determined by the IND Sponsor) and is possibly, probably, or definitely related to the 
study agent;  
OR 
• Any safety issue that the Site Investigator determines should pause administration of 
the study agent to a single subject or to all subjects in a specific group.   
 
The IND Sponsor, in collaboration with the PI, may also pause for an individual subject 
or entire group if a safety concern is identified during routine aggregate data analysis. 
 
11.10.1 
Reporting of Pausing for a Subject or Group 
If a pausing requirement is met, a description of the adverse event(s) or safety issue 
must be reported by the PI by fax or email within one business day to the Sponsor CSO, 
the IRB,  the DSMB, and AstraZeneca.  
 
11.10.2 
Resumption of a Paused Study 
The IND Sponsor in collaboration with the PI and DSMB will determine if it is safe to 
resume administration of the study agent to the subject/group. The IND Sponsor will 
notify the PI of this decision. The PI will notify the IRB and AstraZeneca of the decision 
to resume administration of the study agent prior to resumption. 
 
11.11 Withdrawal Criteria for an Individual Subject 
 
An individual subject will be withdrawn for any of the following:  
• An individual subject’s decision.  
(The Investigator should attempt to determine the reason for the subject’s decision.) 
• Non-compliance with study procedures to the extent that it is potentially harmful to 
the subject or to the integrity of the study data. 
• A change in the subject’s baseline condition after enrollment so that the subject no 
longer meets the following exclusion criteria.    
 
§ Malignancy (other than a resectable skin cancer) 
§ HIV infection or any other known immunodeficiency. 
§ Hepatitis B or C infection 
§ Positive test for FIP1L1/PDGFRA fusion gene 
§ Suspicion of drug or alcohol abuse 
§ Treatment with another investigational agent 
 

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11.12 
Replacement of a Subject Who Discontinues Study 
Treatment 
Subjects who discontinue study treatment after the first dose will not be replaced.  
 
11.13 
Unblinding of the study 
 
11.13.1 
Scheduled unblinding 
 
The study drug assignments will be unblinded after all 20 subjects have enrolled and 
completed the 13 week visit. At that time, efficacy and safety data collected through this 
time point will be analyzed.  
 
11.13.2 
Intentional Unscheduled Unblinding for Treatment Conditions 
Prior to breaking the treatment blind, the PI will be consulted. The research pharmacist 
will keep the treatment code list locked in a secure area and can be reached 24 hours a 
day to rapidly access subject unblinding codes if necessary. If a subject’s treatment 
assignment is unblinded, the information will be provided only to the individuals needing 
it for treatment decisions, with documentation of the event and the reason for unblinding 
recorded in the subject’s research record.  
11.13.3 
Reporting of Unblinding 
The PI must report all cases of unblinding (whether intentional or unintentional) in 
writing to the IRB, DSMB and AstraZeneca within 2 business days after the unblinding. 
If a serious adverse event (SAE) has resulted in unblinding, this information will be 
included in the SERF. Incidences of unblinding in and of themselves will be reported to 
the OCRPRO Clinical Safety Office. A detailed report of the event that resulted in the 
unblinding will be sent to the DSMB, AstraZeneca and the IRB.  
 
11.14 
Safety Oversight 
 
11.14.1 
Safety Review and Communications Plan (SRCP) 
A Safety Review and Communication Plan (SRCP) has been developed for the 
protocol. The SRCP is an internal communications document between the PI and the 
CSO, which delineates the safety oversight responsibilities of the PI, the CSO, and 
other stakeholders. The SRCP also includes the overall plan for conducting periodic 
safety surveillance assessments.  
 
11.14.2 
Sponsor Medical Monitor (SMM) 
A Medical Monitor, representing the IND Sponsor (OCRPRO), has been appointed for 
oversight of safety in this clinical study. The Sponsor Medical Monitor will be 

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responsible for performing safety assessments as outlined in a Safety Review and 
Communications Plan (SRCP).  
 
11.14.3 
Data and Safety Monitoring Board (DSMB)  
The NIAID Intramural DSMB will review the study prior to initiation and twice a year 
thereafter. The Board may convene additional reviews as necessary.  The Board will 
review the study data to evaluate the safety, efficacy, study progress, and conduct of 
the study. All serious adverse events, all unanticipated problems, and all IND Safety 
Reports will be reported by the PI to the DSMB at the same time they are submitted to 
the IRB or IND Sponsor. The PI will notify the DSMB of any cases of intentional or 
unintentional unblinding as soon as possible. The PI will notify the Board at the time 
pausing or halting criteria are met and obtain a recommendation concerning 
continuation, modification, or termination of the study. The PI will submit the written 
DSMB summary reports with recommendations to the IRB.  
 
11.14.4 
Unblinded Pathologist 
An NIH pathologist who is not involved in the clinical care of the study subjects will 
review all blinded CBCs and differentials obtained during the placebo-controlled portion 
of the study within 24 hours of the blood draw. Significant abnormalities (i.e., laboratory 
values that meet criteria for a grade 3 or 4 AE, SAE or that the pathologist deems 
clinically significant),will be reported to the PI and study coordinator immediately.  Other 
laboratory abnormalities that represent grade 1 or 2 AEs and require no specific medical 
intervention, with the exception of the absolute eosinophil counts, will be reported to the 
PI and study coordinator in a weekly summary table.  
 
12 Clinical Monitoring Structure 
 
12.1 
Site Monitoring Plan  
As per ICH-GCP 5.18 and FDA 21 CFR 312.50, clinical protocols are required to be 
adequately monitored by the study sponsor. This study monitoring will be conducted 
according to the “NIAID Intramural Clinical Monitoring Guidelines. Monitors under 
contract to the NIAID/OCRPRO will visit the clinical research site to monitor aspects of 
the study in accordance with the appropriate regulations and the approved protocol. The 
objectives of a monitoring visit will be: 1) to verify the existence of signed informed 
consent documents and documentation of the ICF process for each monitored subject; 
2) to verify the prompt and accurate recording of all monitored data points, and prompt 
reporting of all SAEs; 3) to compare CRIMSON data abstracts with individual subjects’ 
records and source documents (subjects’ charts, laboratory analyses and test results, 
physicians’ progress notes, nurses’ notes, and any other relevant original subject 
information); and 4) to help ensure investigators’ are in compliance with the protocol. 
The monitors also will inspect the clinical site regulatory files to ensure that regulatory 
requirements (Office for Human Research Protections-OHRP), FDA, and applicable 

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guidelines (ICH-GCP) are being followed. During the monitoring visits, the investigator 
(and/or designee) and other study personnel will be available to discuss the study 
progress and monitoring visit. 
 
The investigator (and/or designee) will make study documents (e.g., consent forms, 
CRIMSON data abstracts and pertinent hospital or clinical records) readily available for 
inspection by the local IRB, the FDA, the site monitors, and the NIAID staff for 
confirmation of the study data.  
 
A specific protocol monitoring plan will be discussed with the Principal Investigator and 
study staff prior to enrollment. The plan will outline the frequency of monitoring visits 
based on such factors as study enrollment, data collection status and regulatory 
obligations.  
 
13 Statistical Considerations 
13.1 
Study Hypotheses 
This randomized, placebo-controlled, double-blind Phase 2 study followed by an open-
label extension is designed to test the hypothesis that benralizumab can safely reduce 
eosinophilia in patients with HES. 
 
13.2 
Sample Size Justification   
In addition to potentially eligible subjects already followed on protocol 94-I-0079, we 
receive 1-2 new patient referrals/week for evaluation and treatment of HES.  
Furthermore, based on prior experience, we anticipate an increase in referrals with the 
availability of a new clinical trial. Thus, it is likely that recruitment of 20 subjects will be 
feasible in a 2 year time frame.   
 
The primary endpoint is a binary response (50% reduction in peripheral eosinophil count 
at 12 weeks).  To compare the 2 groups, we will perform a one-sided Fisher’s exact test 
at the 2.5% level (this is essentially the same as a two-sided central Fisher’s exact test 
at the 5% level). For the power calculations, we make some assumptions. First, we 
assume that we have 10 subjects in each arm of the study. We expect that at 12 weeks 
virtually none of the subjects randomized to placebo will have a response, so we set 
that value to 1%. We calculate the power for different levels of response for the subjects 
on benralizumab. The results are listed inTable 2. Thus, we need 60% responders in 
the benralizumab group in order to get 79% power to reject at the one-sided 2.5% level 
(or equivalently at the two-sided 5% level) if we have 10 in each group as planned. If we 
are only able to recruit 6 in each group by the end of the 2 year accrual, then we need 
90% responders to get over 86.4% power. 
 
Table 2 
Power Estimates  
Percent 
Responders 
Percent 
Responders on 
Power to Reject 
(in Percent) 
Power to Reject 
(in Percent) 
Power to Reject 
(in Percent) 

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on Placebo 
Benralizumab 
N=10 per group 
N=8 per group 
N=6 per group 
1 
50 
57.9 
34.6 
10.4 
1 
60 
79.0 
57.2 
22.2 
1 
70 
92.3 
78.5 
40.2 
1 
80 
98.2 
93.2 
63.2 
1 
90 
99.8 
99.2 
86.4 
13.3 
Description of the Analyses  
 
• Safety Analysis:  All safety data will be summarized with descriptive statistics 
(number of subjects [N], mean, standard deviation [SD], median, minimum, and 
maximum) for continuous variables, and frequency and percentage for discrete 
variables. The safety summary will include AEs, serious adverse events (SAEs), 
clinical laboratory data, vital signs, physical examination, and ECG data. All 
individual subject data will be listed by subject.    
• Efficacy Analysis: The primary analysis compares the proportion of subjects with a 
≥50 % change in AEC at 12 weeks in the 2 randomized arms. If there is dropout, the 
primary analysis will be the intent-to-treat analysis, which includes all subjects who 
received the Day 0 treatment. We will compare with a one-sided Fisher’s exact test 
at the 2.5% level of significance, or equivalently a two-sided central Fisher’s exact 
test at the 5% level.   
• For the secondary analysis comparing the 2 groups on the post-treatment AEC at 
12 weeks as a percentage of the pre-treatment AEC, we use a Wilcoxon-Mann-
Whitney test.  
• There are other  secondary endpoints with continuous responses that measure a 
change from pre-treatment to after 12 weeks of treatment:  for example,  % bone 
marrow eosinophils, and  % bone marrow myeloid precursors.  These will be 
analyzed similarly to the percentage of pretreatment AEC.  
• As exploratory analyses, we may use a Mixed-Effect Model Repeated Measure 
(MMRM) model to analyze changes in AEC over time. The dependent variable will 
be the percentage of baseline AEC at post-baseline protocol-specified visits (up to 
the 12 week visit). Treatment group will be fitted as the explanatory variable, 
together with visit, the interaction between visit and treatment. Visit will be fitted as a 
categorical variable, and the variance-covariance matrix will be assumed to be 
unstructured. If the procedure does not converge, then a compound symmetric 
variance-covariance matrix will be used instead.  
• Calculation or derivation of pharmacokinetic variables 
The PK analyses will be performed at (or under the guidance of) AstraZeneca 
Research and Development. 
Due to the limited sampling schedule, the PK assessment will be primarily based on 
the observed steady-state serum trough (predose) concentrations, Ctrough. Empirical 
evaluation of potential impact of demographic covariates and ADA on Ctrough will be 
conducted. Serum concentrations of benralizumab, summary statistics, empirical 
covariate analysis results and PK profiles will be provided in a clinical PK report (an 
addendum to the CSR). 

Protocol Version 12.2 
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Page 56 of 76 
To further characterize the pharmacokinetic properties of benralizumab in HES, the 
PK data will be merged with those from other clinical studies for a population-
based, which will be presented in a separate pharmacometrics report outside of the 
CSR. 
• Calculation or derivation of immunogenicity variables 
ADA assessments will be conducted utilizing a tiered approach (screen, confirm, 
titer). Evaluations will be made at baseline (prior to benralizumab administration), 
and at specified time points during the treatment and follow up phases of the study 
or discontinuation.  ADA titers by treatment group and visit will be summarized. The 
association of ADA status (positive or negative) with treatment-emergent adverse 
events (TEAEs)/ treatment-emergent serious adverse events (TESAEs), 
benralizumab concentration and blood eosinophil levels will be evaluated. In 
addition, the association of ADA titers (≥median titer vs. < median titer) with TEAEs/ 
TESAEs, benralizumab concentration and blood eosinophil levels will be evaluated 
for ADA positive subjects only.  
13.4 
Final Analysis Plan  
The primary endpoint is the number of subjects with a ≥50% change in AEC.  The 
details of the statistical tests used for this endpoint is described in Section 13.3. For this 
test and all tests, we define significance using a two-sided 5% level or equivalently a 
one-sided 2.5% level. If the study shows that there is a significant reduction in AEC, this 
would merit further study of benralizumab in HES. This design relies on the assumption 
that the type of HES patients included in this study would not have 50% improvement in 
their eosinophil count in the absence of a change in therapy. This is a well-established 
assumption in the HES research community. 
This single center trial has 2 parts: 1) a randomized, double-blind comparison of sc 
benralizumab vs. placebo every 4 weeks for 12 weeks, 2) an open-label extension of sc 
benralizumab every 4 weeks for 12-36 weeks. The primary endpoint and secondary and 
exploratory endpoints based on the data from the first part of the study will be analyzed 
once all 20 subjects have completed the 13 weeks visit and data is unblinded.  
Since there are only 20 patients in the study, both an intent-to-treat and a per-protocol 
analysis may be done. For the intent-to-treat analysis, we will impute a “worst case” 
post-treatment AEC, whereby we will use the maximum of the baseline AEC or the last 
AEC as the post-treatment AEC for analysis.  If a patient does not complete treatment, 
that patient may be removed from the per-protocol analysis.  
Although we do not specify the exploratory analyses in advance, we do note that care 
will be taken in making inferences when many analyses are undertaken. If needed 
multiple comparison adjustments will be made.  
14 Ethics/Protection of Human Subjects 
 

Protocol Version 12.2 
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Page 57 of 76 
14.1 
Informed Consent Process 
Informed consent is a process where information is presented to enable persons to 
voluntarily decide whether or not to participate as a research subject. It is an on-going 
conversation between the human research subject and the researchers which begins 
before consent is given and continues until the end of the subject's involvement in the 
research. Discussions about the research will provide essential information about the 
study and include: purpose, duration, experimental procedures, alternatives, risks and 
benefits.  Subjects will be given the opportunity to ask questions and have them 
answered.  
The subjects will sign the informed consent document prior to undergoing any research 
procedures. The subjects may withdraw consent at any time throughout the course of 
the trial.  A copy of the informed consent document will be given to the subjects for their 
records. The researcher will document the signing of the consent form in the subject’s 
medical record. The rights and welfare of the subjects will be protected by emphasizing 
to them that the quality of their medical care will not be adversely affected if they decline 
to participate in this study.  
 
14.2 
Subject Confidentiality 
All records will be kept confidential to the extent provided by federal, state and local law. 
The study monitors and other authorized representatives of the Sponsor may inspect all 
documents and records required to be maintained by the Investigator, including but not 
limited to, medical records.  Records will be kept locked and all computer entry and 
networking programs will be done with coded numbers only.  Clinical information will not 
be released without written permission of the subject, except as necessary for 
monitoring by IRB, the FDA, the NIAID, the OHRP, AstraZeneca or the sponsor’s 
designee. 
15 Data Handling and Record Keeping 
15.1 
Data Capture and Management  
 
Study data will be maintained in CRIMSON and collected directly from subjects during 
study visits and telephone calls, or will be abstracted from subjects’ medical records. 
Source documents include all recordings of observations or notations of clinical 
activities and all reports and records necessary to confirm the data abstracted for this 
study. Data entry into CRIMSON will be performed by authorized individuals. The 
Investigator is responsible for assuring that the data collected are complete, accurate, 
and recorded in a timely manner. 
If a subject receives drug at an outside site on the long-term extension,(after week 48), 
the outside PI will provide documentation of drug administration, AE/SAEs and 
laboratory testing as required by the protocol. These will be entered into CRIMSON by 
the NIH study team.  

Protocol Version 12.2 
August 6, 2020 
 
Page 58 of 76 
 
15.2 
Record Retention 
 
The investigator is responsible for retaining all essential documents listed in the ICH 
Good Clinical Practice Guideline.  Study records will be maintained by the PI for a 
minimum of 3 years and in compliance with institutional, IRB, state, and federal medical 
records retention requirements, whichever is longest. All stored records will be kept 
confidential to the extent required by federal, state, and local law. 
Should the investigator wish to assign the study records to another party and/or move 
them to another location, the investigator will provide written notification of such intent to 
OCRPRO/NIAID with the name of the person who will accept responsibility for the 
transferred records and/or their new location. Destruction or relocation of research 
records will not proceed without written permission from NIAID/OCRPRO. 

Protocol Version 12.2 
August 6, 2020 
 
Page 59 of 76 
Appendix A: Scientific References 
 
 
1. Ogbogu, P.U., Bochner, B.S., Butterfield, J.H., et al. Hypereosinophilic 
syndromes: a multicenter, retrospective analysis of clinical characteristics and 
response to therapy. J Allergy Clin Immunol 2009 124:1319-1325 
2. Rothenberg, M.E., Klion, A.D., Roufosse, F.E, et al. Treatment of 
Hypereosinophilic Syndrome With Mepolizumab. New Engl J Med 2008 
358:1215-28 
3. Roufosse, F.E., Kahn, J.E., Gleich, G.G., et al. Long-term safety of 
mepolizumab for the treatment of hypereosinophilic syndrome. J Allergy and Clin 
Immunol 2013; 113:461-7 
 
4. Menzies-Gow, A., Flood-Page, P., Sehmi, R., et al. Anti-IL-5 (mepolizumab) 
therapy induces bone marrow eosinophil maturational arrest and decreases 
eosinophil precirsors in the bronchial mucosa of atopic asthmatics. J Allergy and 
Clin Immunol 2003; 111:714-9 
 
5. Kim, Y.J., Prussin, C., Martin, B., et al. Mechanism of rebound eosinophilia 
following treatment of hypereosinophilic syndrome and eosinophilic 
gastroenteritis with monoclonal anti-IL-5 antibody, SCH55700. J Allergy Clin 
Immunol 2004 114(6):1449-55 
6. Tavernier J, Devos R, Cornelis S, et al. A human high affinity interleukin-5 
receptor (IL5R) is composed of an IL5-specific a chain and a b chain shared with 
the receptor for GM-CSF. Cell 1991;66:1175-84. 
 
7. Wilson, T.M., Maric, I., Shukla, J., et al. Interleukin-5 receptor a levels in 
patients with marked eosinophilia or mastocytosis. J Allergy Clin Immunol 2011 
128(5):1086-92 
 
8. Kolbeck R, Kozhich A, Koike M, Peng L, Andersson CK, Damschroder MM, et 
al. MEDI-563, a humanized anti-IL-5 receptor alpha mAb with enhanced 
antibody-dependent cell-mediated cytotoxicity function. J. Allergy Clin Immunol. 
2010 Jun;125(6):1344-1353.e2. 
 
9. Busse, W.W., Katial, R., Gossage, D., et al. Safety profile, pharmacokinetics, 
and biologic activity of MEDI-563, an anti-IL-5 receptor alpha antibody in a phase 
I study of subjects with mild asthma. J Allergy Clin Immunol 2010 
125:1237044.e2 
 
10. Stewart, J. Developmental toxicity testing of monoclonal antibodies: an 
enhanced pre- and postnatal study design option. Reprod Toxicol. 2009;28(s): 
220-225. 
 

Protocol Version 12.2 
August 6, 2020 
 
Page 60 of 76 
 
11. Laviolette M, Gossage DL, Gauvreau G, et al. Effects of benralizumab on 
airway eosinophils in asthmatic patients with sputum eosinophilia. J Allergy Clin 
Immunol 2013; 132:1086-96. 
 
12. Chu, V.T., Frohlich, A., Steinhauser, G., et al. Eosinophils are required for the 
maintenance of plasma cells in the bone marrow. Nat Immunol 2011; 12:151-9. 
 
13. Wu, D., Molofsky, A.B., Liang, H.E., et al. Eosinophils sustain adipose 
alternatively activated macrophages associated with glucose homeostasis. 
Science 2011 332:243-7. 
 
14. Lee, J.J., Dimina, D., Macias, M.P., et al. Defining a link with asthma in mice 
congenitally deficient in eosinophils. Science 2004 305:1773-6. 
 
15. Humbles, A.A., Lloyd, C.M., McMillan, S.J. A critical role for eosinophils in 
allergic airways remodeling. Science 2004 305:1776-9. 
 
16. Bleeker, E.R., FitzGerald, J.M., Chanez P., et al. Efficacy and safety of 
benralizumab for patients with severe asthma uncontrolled with high dosage 
inhaled corticosteroids and long-actng b-agonists (SIROCCO): a randomised, 
multicenter, placebo-controlled phase 3 trial. Lancet 2016 Sep 2. pii:S0140-
6736(16)31324-1. doi: 10.1016/ S0140-6736(16)31324-1. [Epub ahead of print] 
 
17. FitzGerald, J.M., Bleeker, E.R., Nair, P., et al. Benralizumab, an anti-
interleukin-5 receptor a monoclonal antibody, as add-on treatment for patients 
with severe, uncontrolled, eosinophilic asthma (CALIMA): a randomised, double-
blind, placebo-controlled phase 3 trial. Lancet 2016 Sep 5. pii:S0140-
6736(16)31322-8. doi: 10.1016/ S0140-6736(16)31322-8. [Epub ahead of print] 
 
18. Park, H.S., Kim, M.K., Imai, N. et al. A phase 2a study of benralizumab for 
patients with eosinophilic asthma in South Korea and Japan. Int Arch Allergy 
Immunol 2016;169:135-145. 
 
19.  Nair, P. , Wenzel, S., Rabe K.F. et al. Oral glucocorticoid-sparing effect of 
benralizumab  in severe asthma. N Engl J Med 2017;376:2448-2548.

Protocol Version 12.2 
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Page 61 of 76 
Appendix B: Schedule of Procedures/Evaluations  
Events 
Baseline 
Placebo-controlled Phase 
  
  
Open Label Phase 
  
  
  
  
  
EXTENSION 
Day 
0 to -14 
Day 
0 
Days 
1,2,3 
Wk 
1,2,
3 
Wk 
4 
Wk 
6 
Wk 
8 
Wk 
10 
Wk 
12 
Days 
85,86,
87 
Wk 
13,14
,15 
Wk 
16 
Wk 
18 
Wk 
20 
Wk 
22 
Wk 
24 
Wk 
28 
Wk 
32 
Wk 
36 
Wk 
40, 
44 
Wk 
48 
Q 6 
Mon
ths 
Q12
Mont
hs 
Window      
  
± 2d 
± 2d 
± 3d 
± 3d 
± 3d 
± 3d 
  
± 2d 
± 2d 
± 3d 
± 3d 
± 3d 
± 3d 
± 4d 
± 4d 
± 4d 
± 4d 
± 4d 
 
± 7d 
 
± 7d 
Informed consent 
X 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
 
Complete medical 
history and 
physical 
examination 
X 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
 
Targeted medical 
history, including 
HES symptom 
questionnaire 
  
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Targeted physical 
examination 
  
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Vital signs, 
including weight 
X 
X6 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Study Drug  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Study Drug 
administration1 
  
X 
  
  
X 
  
X 
  
X 
  
  
X 
  
X 
  
X3 
X3 
X3 
X3 
X3 
  
 
 
tudy Procedures 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
 
  
Tdap vaccine 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
X2 
  
  
  
  
  
  
 
  
ECG (12-lead) 
X 
  
  
  
  
  
  
  
X 
  
  
  
  
  
  
X 
  
  
X 
  
X 
 
X 
Echocardiogram 
X 
  
  
  
  
  
  
  
X 
  
  
  
  
  
  
X 
  
  
X 
  
X 
 
X 
Pulmonary 
function tests 
X 
  
  
  
  
  
  
  
X 
  
  
  
  
  
  
X 
  
  
X 
  
X 
 
X 
Bone marrow 
aspirate and 
X 
  
  
  
  
  
  
  
X 
  
  
  
  
  
  
  
  
  
  
  
  
 

Protocol Version 12.2 
August 6, 2020 
 
Page 62 of 76 
biopsy 
Tissue biopsy of 
affected organs 
X4 
  
  
  
  
  
  
  
X4 
  
  
  
  
  
  
X4 
  
  
X4 
  
X4 
 
X4 
Clinical and safety 
laboratory testing 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
 
  
Electrolyte Panel 
X 
X6 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Hepatic Panel 
X 
X6 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Mineral Panel  
X 
X6 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
CBC w/ differential 
X 
X6 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
PT/PTT 
X 
  
  
  
  
  
  
  
X 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
ESR, CRP 
X 
  
  
  
X 
  
X 
  
X 
  
  
X 
  
X 
  
X 
X  
 X 
X 
X  
X 
X 
X7 
LDH, CPK 
X 
 X 
 X 
X 
X 
X  
X 
 X 
X 
X  
X  
X 
 X 
X 
 X 
X 
X  
 X 
X 
 X 
X 
X 
X 
Total Protein 
X 
 
 
 
X 
 
 
 
X 
 
 
X 
 
X 
 
X 
X 
X 
X 
X 
X 
X 
X7  
Troponin 
X 
 
 
 
 
 
 
 
X 
 
 
 
 
 
 
X 
 
 
X 
 
X 
 
X7 
Uric acid 
X 
 
 
 
× 
 
× 
 
X 
 
 
× 
 
× 
 
X 
× 
× 
X 
× 
X 
× 
X7 
HbgA1c 
X 
  
  
  
  
  
  
  
X 
  
  
  
  
  
  
X 
  
  
 
  
 
  
 
Urinalysis 
X 
X6 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Serum pregnancy 
test 
X5 
X5,6 
  
  
X5 
  
X5 
  
X5 
  
  
X5 
  
X5 
  
X5 
X5 
X5 
X5 
X5 
X5 
X5 
X5 
Serum B12 levels 
X 
  
  
  
  
  
  
  
X 
  
  
  
  
  
  
X 
  
  
X 
  
X 
  
X7 
Serum tryptase 
levels 
X 
X6 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Serum 
immunoglobulin 
levels 
X 
  
  
  
  
  
  
  
X 
  
  
  
  
  
  
X 
  
  
X 
  
X 
 
X 
Serum IgE levels 
X 
  
  
  
  
  
  
  
X 
  
  
  
  
  
  
X 
  
  
X 
  
X 
 
X 
Tetanus Toxoid 
IgG Antibody 
  
  
  
  
  
  
  
  
X2 
  
  
  
  
  
  
  
X2 
  
  
  
  
 
Research 
laboratory studies 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
 

Protocol Version 12.2 
August 6, 2020 
 
Page 63 of 76 
Eosinophil and 
PBMC purification 
from whole blood 
X 
  
  
  
  
  
  
  
X 
  
  
  
  
  
  
X 
  
  
X 
  
X 
 
X 
Serum, plasma 
and urine for 
eosinophil granule 
protein and 
mediator levels 
X 
X6 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X10 
Serum for PK 
studies and ADA 
measurement 
X 
  
  
  
X 
  
X 
  
X 
  
  
X 
  
X 
  
X 
X 
X 
X 
X 
X 
X 
X 
Bone marrow flow 
cytometry 
X 
  
  
  
  
  
  
  
X 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
T and B cell 
receptor 
rearrangement 
studies  
X 
  
  
  
  
  
  
  
X 
  
  
  
  
  
  
  
  
  
  
  
X 
  
X 
IL-5 Receptor 
expression 
X 
  
  
  
  
  
  
  
X 
  
  
  
  
  
  
X 
  
  
X 
  
X 
  
 
Whole Blood 
pre/post 
 
X 
 
 
 
 
 
 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
TBNK cell subsets 
 
 
 
 
 
 
 
 
X 
 
 
 
 
 
 
X 
 
 
X 
 
X 
 
X 
Study 
Assessments 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Assessment of 
end organ 
involvement 
X 
  
  
  
  
  
  
  
X 
  
  
  
  
  
  
X 
  
  
X 
  
X 
  
X 
Concomitant 
medication history 
X 
X6 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Collection of 
adverse events 
  
X6 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Protocol Version 12.2 
August 6, 2020 
 
Page 64 of 76 
Appendix C: Blood Volumes for Specimen Collection  
 
Evaluations 
Study Schedule 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1 Visit 
BL 
01 
02 
03 
04 
05 
06 
07 
08 
09 
10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
20 
21 
22 
23 
24 
25 
26 
27 
28 
29 
30 
Week of 
Study 
0 
1 
1  
1 
1 
1 
2 
3 
4 
6 
8 
10 
12 
12 
12 
12 
13 
14 
15 
16 
18 
20 
22 
24 
28 
32 
36 
40 
44 
48 
Day of 
Study 
-14 
to  
0 
40 
1 
2 
3  
7 
14 
21 
28 
42 
56 
70 
84 
85 
86 
87 
91 
98 
105 
112 
126 
140 
154 
168 
196 
224 
252 
280 
308 
336 
Clinical 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chemistry 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
8 
CBC/diff 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
3 
PT/PTT 
4.5 
 
 
 
 
 
 
 
 
 
 
 
4.5 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
ESR, CRP 
5 
 
 
 
 
 
 
 
5 
 
5 
 
5 
 
 
 
 
 
 
5 
 
5 
 
5 
5 
5 
5 
5 
5 
5 
LDH, CPK 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
4 
Troponin 
4 
 
 
 
 
 
 
 
 
 
 
 
4 
 
 
 
 
 
 
 
 
 
 
4 
 
 
4 
 
 
4 
HbA1c 
3 
 
 
 
 
 
 
 
 
 
 
 
3 
 
 
 
 
 
 
 
 
 
 
3 
 
 
 
 
 
 
Pregnancy 
4 
 
 
 
 
 
 
 
4 
 
4 
 
4 
 
 
 
 
 
 
4 
 
4 
 
4 
4 
4 
4 
4 
4 
4 
Serum B12 
4 
 
 
 
 
 
 
 
 
 
 
 
4 
 
 
 
 
 
 
 
 
 
 
4 
 
 
4 
 
 
4 
Serum 
4 
 
 
 
 
 
 
 
 
 
 
 
4 
 
 
 
 
 
 
 
 
 
 
4 
 
 
4 
 
 
4 
Serum Ig 
4 
 
 
 
 
 
 
 
 
 
 
 
4 
 
 
 
 
 
 
 
 
 
 
4 
 
 
4 
 
 
4 
Serum IgE 
4 
 
 
 
 
 
 
 
 
 
 
 
4 
 
 
 
 
 
 
 
 
 
 
4 
 
 
4 
 
 
4 
Tetanus Ab 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4 
 
4 
 
 
 
 
 
Research 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Cell 
50 
 
 
 
 
 
 
 
 
 
 
 
50 
 
 
 
 
 
 
 
 
 
 
60 
 
 
60 
 
 
60 
Serum 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
Plasma 
Storage 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
6 
PK, ADA 
6 
 
 
 
 
 
 
 
6 
 
6 
 
6 
 
 
 
 
 
 
6 
 
6 
 
6 
6 
6 
6 
6 
6 
6 
TCR, BCR 
4.5 
 
 
 
 
 
 
 
 
 
 
 
4.5 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4.5 
Flow 
t
t
9 
 
 
 
 
 
 
 
 
 
 
 
9 
 
 
 
 
 
 
 
 
 
 
9 
 
 
9 
 
 
9 
WholeBlood 
 
20 
 
 
 
 
 
 
 
 
 
 
20 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Daily Vol 
(mL) 
133 
47 
27 
27 
27 
27 
27 
27 
42 
27 
42 
27 
153 
27 
27 
27 
27 
27 
27 
42 
27 
42 
31 
134 
44 
42 
131 
42 
42 
136 
Cum Vol 
(mL) 
133 
180 
207 
234 
261 
288 
315 
342 
384 
411 
453 
480 
633 
660 
687 
714 
741 
768 
795 
837 
864 
906 
937 
1071 
1115 
1157 
1288 
1330 
1372 
1508 
Vol/8 wks 
 
 
 
 
 
 
 
 
 
 
453 
 
 
 
 
 
 
 
 
357 
 
 
 
399 
 
86 
 
173 
 
178 
 

Protocol Version 12.2 
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Per NIH MEC Policy M95-9, maximum blood volumes drawn for research purposes for an adult subject (aged 18 years or older) may not exceed: 10.5 mL/kg or 
550 mL, whichever is smaller, over any 8week period. Exceptions to this policy shall be approved by the IRB.

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Appendix D: Research Studies 
 
Research blood and bone marrow will be collected at a variety of timepoints to 1) 
assess the effects of benralizumab on eosinophil activation and other biomarkers 
of disease activity in HES, 2) assess the effects of benralizumab on basophils, 
mast cells and eosinophil precursors, 3) identify predictors of 
response/resistance to benralizumab, 4)  explore the immunologic consequences 
of eosinophil depletion, including the effects of plasma cells and vaccine 
responses, and 5) examine the role of eosinophil and/or NK activation in post-
injection reactions.   
 
1) 
Eosinophil activation and biomarkers of disease activity in HES 
 
Eosinophil activation will be assessed in a variety of ways including: 
 
• measurement of serum levels of eosinophil degranulation 
products (MBP, ECP, EDN, EPO) using a suspension array 
assay in multiplex 
 
• assessment of eosinophil surface marker expression, including 
CD69 and CD25, in whole blood and bone marrow aspirates by 
flow cytometry 
 
• immunohistochemical staining of tissue biopsies obtained for 
clinical indications for degranulation products 
 
Although validated biomarkers of disease activity in HES have not been 
identified to date, a number of mediators, including cytokines (IL-5, 
chemokines (i.e., TARC, eotaxin), and soluble receptors (i.e., soluble IL-5 
receptor alpha, soluble CD25), have been shown to correlate with disease 
activity in some settings. Since subjects will be maintained on a stable 
HES treatment regimen for the first 12 weeks of benralizumab therapy, 
blood samples obtained immediately prior to and after 12 weeks of 
therapy will be used to explore potential biomarkers. Eosinophils, 
peripheral blood mononuclear cells and plasma will be purified from 
peripheral blood (60 cc) using standard methods. Plasma will be stored at 
-80oC. Depending on the total numbers of cells isolated, the purified 
eosinophils and PBMC may be processed for RNA, viably frozen in liquid 
nitrogen (PBMC only) and/or snap frozen for proteomic analysis.   
 
2) 
Basophil, mast cell and eosinophil precursors 
 
• Basophils: Due to the low numbers of circulating basophils in 
peripheral blood, basophil numbers and activation will be assessed 
by whole blood flow cytometry using CCR3 and CD203c, a specific 
marker of basophil activation.  

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• Mast cells: Mast cells will be quantified and assessed for spindle-
shape (activation) in bone marrow biopsy specimens stained for 
tryptase and CD117 before and during benralizumab therapy. Flow 
cytometry of the aspirate specimens will be used to assess surface 
markers of activation (CD2 and CD25). Serum tryptase levels will 
also be assessed.  
 
• Eosinophil precursors: Eosinophil precursors will be assessed 
morphologically and by flow cytometry using antibodies to IL-5R 
and CD34 before and after 12 weeks of benralizumab therapy.   
 
3) 
Predictors of response/resistance to benralizumab 
 
• Prior studies have shown a correlation between decreased IL-5R 
levels on the surface of eosinophils and increased soluble IL-5R 
levels in serum (7).  Consequently, surface expression of IL-5R will 
be quantified by whole blood flow of eosinophils using Quantibrite 
beads and soluble IL-5R will be measured by ELISA before and at 
12, 24, 36 and 48 weeks of benralizumab therapy.  
 
• The presence of anti-drug antibodies will be assessed before and 
at specified time points during the study. Drug levels will also be 
assessed. 
 
4) 
Immunologic consequences of benralizumab therapy 
 
Activated eosinophils are a source of a wide variety of cytokines, 
chemokines, and other mediators. Thus, depletion of eosinophils is 
in patients with HES is likely to have secondary effects on other 
immune cells. Whole blood flow cytometry will be perfomed at 
baseline and every 12 weeks on benralizumab therapy to look at 
T/B/NK cell numbers, activation status and cytokine production. In 
addition, PBMC will be purified from whole blood at the same time 
points for generation of supernatants for cytokine analyses by 
suspension array in multiplex and isolation of RNA for microarray 
and/or RNAseq analysis.  
 
• In view of murine studies demonstrating that eosinophil-deficient 
mice have decreased plasma cells and impaired repsonses to 
secondary immunization with T cell dependent antigens (12), 
plasma cells will be quantified in the bone marrow prior to and after 
12 weeks of benralizumab therapy. In addition, anti-tetanus 
antibody responses will be assessed in all subjects at week 28 (6 
weeks following immunization).  
 

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5) 
Mechanism of post-treatment reactions 
 
• Post-injection reactions have been observed in some, but not all, 
subjects 4-6 hours following the first dose of benralizumab vs. 
placebo or the first dose of open-label benralizumab. These 
reactions have been characterized by fever, nausea, fatigue and 
mylagias and a rise in LDH. Reactions have not been observed 
following injections at other study time points and the severity of the 
reaction does not appear to be related to pre-treatment eosinophil 
count. Similar reactions have not been described in studies of 
benralizumab in subjects with asthma, but were seen in some 
subjects in phase i dose finding studies.  
 
• Potential mechanisms for these reactions include 1) NK activation 
and cytokine release and/or 2) eosinophil lysis. In order to begin to 
examine these possibiltiies, whole blood flow will be performed to 
assess markers of activation and degranulation of NK cells (CD63 
and CD107a) and eosinophils (CD69 and CD63) prior to and at 3-6 
hours post the study drug injection at week 0 and week 12.  Plasma 
levels of cytokines, granule proteins and other inflammatory 
markers will also be assessed.  
 

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Appendix E: HES Questionnaire 
 
 
Symptom 
 
 
 
Y      N 
If yes, please specify: 
 
Itching Rashes? 
 
 
 
Fatigue? 
Joint Pain? 
Muscle Aches? 
Chest Pain? 
Shortness of breath or wheezing? 
Abdominal pain or GI symptoms? 
Neuropathy? 
Hives? 
Angioedema? 
Allergies or sinus symptoms? 
Mouth sores? 
Fever? 
Weight loss? 
Lymphadenopathy? 
 

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Appendix F: FASENRA PEN: Instructions for Use 
 
Instructions for Use 
FASENRA PEN™ (fas-en-rah) 
(benralizumab) 
for Subcutaneous Injection 
Single-dose Autoinjector 
 
Before using your FASENRA PEN, your healthcare provider should show you or 
your caregiver how to use it the right way. 
 
Read this Instructions for Use before you start using your FASENRA PEN 
and each time you get a refill. There may be new information. This information 
does not take the place of talking to your healthcare provider about your 
medical condition or your treatment. 
 
If you or your caregiver have any questions, talk to your healthcare provider. 
 
Important information: 
 
• Store FASENRA in a refrigerator between 36°F to 46°F (2°C to 8°C) in 
its original carton until you are ready to use it. 
• FASENRA may be kept at room temperature between 68°F to 77°F (20°C to 
25°C) for a maximum of 14 days. 
• Once removed from the refrigerator and brought to room temperature, 
FASENRA must be used within 14 days or thrown away (disposed of). 
 
Do not use your FASENRA PEN if: 
• it has been frozen 
• it has been dropped or damaged 
• the security seal on the carton has 
been broken 
• the expiration date (EXP) has 
passed 
Do not: 
• shake your FASENRA PEN 
• share or reuse your FASENRA 
PEN 
• expose your FASENRA PEN to 
heat 
 
If any of these happen, throw away the FASENRA PEN in a puncture-resistant 
sharps disposal container and use a new FASENRA PEN. 
Each FASENRA PEN contains 1 dose of FASENRA that is for one time use 
only. 
Keep FASENRA and all medicines out of the sight and reach of children. 
 
Your FASENRA PEN  

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Do not remove the cap until you have reached Step 6 of these instructions and 
are ready to inject FASENRA. 
Before use 
After Use 
 
 
 
 
 
 
Step 1 – Gather supplies 
• 1 FASENRA PEN from the refrigerator 
• 1 alcohol wipe 
• 1 cotton ball or gauze 
• 1 bandage 
• 1 puncture-resistant sharps disposal container. See Step 10 for instructions 
on how to throw away (dispose of) the used FASENRA PEN safely. 
 
 
 
 
 
FASENRA 
PEN 
Alcohol 
wipe 
Cotton ball or 
gauze 
Bandage 
Sharps container 
 
Step 2 – Prepare to use your FASENRA PEN 
Check the expiration date (EXP). Do not use if the 
expiration date has passed. 
Let FASENRA warm up at room temperature between 
68°F to 77°F (20°C to 25°C) for about 30 minutes before 
giving the injection. 
Do not warm the FASENRA PEN in any other way. For 
example, do not warm it in a microwave or hot water, or put it 
near other heat sources. 
Use FASENRA within 14 days of removing from the 
refrigerator. After 14 days, throw away the FASENRA PEN. 
Do not remove the cap until you have reached Step 6. 
 
 
Label with 
expiration date 
Liquid 
medicine 
Cap 
Viewing 
window 
Needle 
Guard 
Green 
plunger 

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Step 3 – Check the liquid 
 
Look at the liquid in the FASENRA PEN 
through the viewing window. The liquid 
should be clear and colorless to slightly 
yellow. It may contain small white particles. 
Do not inject FASENRA if the liquid is cloudy, 
discolored, or contains large particles. 
You may see small air bubbles in the liquid. 
This is normal. You do not need to do 
anything about it. 
Step 4 – Choose the injection site 
 
If you are giving yourself the injection, the 
recommended injection site is the front of 
your thigh or the lower part of your stomach 
(abdomen). 
A caregiver may inject you in the upper-arm, 
thigh, or abdomen. Do not try to inject 
yourself in the arm. 
For each injection, choose a different site that 
is at least 1-inch (3-cm) away from where you 
last injected. 
 
Do not inject: 
• into the 2-inch (5-cm) area around your 
belly-button 
• where the skin is tender, bruised, scaly or 
hard 
• into scars or damaged skin 
• through clothing 
Step 5 – Clean the injection site 
 
Wash your hands well with soap and water. 
Clean the injection site with an alcohol wipe in 
a circular motion. Let it air dry. 
Do not touch the cleaned area before 
injecting. 
Do not fan or blow on the cleaned area. 
Step 6 – Pull off the cap 
Caregiver 
 site only 

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Hold the FASENRA PEN with 1 hand. 
Carefully pull the cap straight off with your 
other hand. 
Put the cap aside to throw away later. 
The green needle guard is now exposed. It is 
there to prevent you from touching the needle. 
Do not try to touch the needle or push on the 
needle guard with your finger. 
Do not try to put the cap back on the 
FASENRA PEN. You could cause the 
injection to happen too soon or damage the 
needle. 
Complete the following steps right away after 
removing the cap. 

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Step 7 – Inject FASENRA 
Follow your healthcare providers instructions on how to inject. You can either 
gently pinch at the injection site or give the injection without pinching the skin. 
Inject FASENRA by following the steps in figures a, b, c, and d. 
Hold the FASENRA PEN in place for the entire injection. 
Do not change the position of the FASENRA PEN after the injection has started. 
 
 
 
 
Position the 
FASENRA PEN 
at the injection 
site. 
Place the needle 
guard of the 
FASENRA PEN 
flat against your 
skin (90 degree 
angle). 
Make sure you 
can see the 
viewing window. 
 
Press down 
firmly. 
You will hear a 
click. A ‘click’ tells 
you the injection 
has started. The 
green plunger will 
move down in the 
viewing window 
during the 
injection. 
Hold down firmly 
for 15 seconds. 
You will hear a 
second ‘click’. 
The second click 
tells you the 
injection has 
finished. The 
green plunger will 
fill the viewing 
window. 
Lift the 
FASENRA PEN 
straight up. 
The needle guard 
will slide down and 
lock into place 
over the needle. 
Step 8 – Check the viewing window 
 
Check the viewing window to make 
sure all the liquid has been injected. 
If the green plunger does not fill the 
viewing window, you may not have 
received the full dose. If this happens or 
if you have any other concerns, call 
your healthcare provider. 
 
 
a 
90° 
b 
c 
 
15 
sec 
d 

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Before 
Injecti
on 
 
 
 
After 
Injecti
on 
 
 
Step 9 – Check the injection site 
 
 
There may be a small amount of blood 
or liquid where you injected. This is 
normal. 
Gently hold pressure over your skin 
with a cotton ball or gauze until the 
bleeding stops. 
Do not rub the injection site. 
If needed, cover the injection site with a 
small bandage. 
Step 10 – Dispose of the used FASENRA PEN safely 
 
 
 
• Each FASENRA PEN contains a 
single dose of FASENRA and 
cannot be reused. 
• Put your used FASENRA PEN in a 
FDA-cleared sharps disposal 
container right away after use. 
Do not throw away the FASENRA PEN 
in your household trash. 
Throw away the cap and other used 
supplies in your household trash. 
 
Disposal guidelines 
 
If you do not have a FDA-cleared sharps disposal container, you may use a 
household container that is: 
• 
made of a heavy-duty plastic, 
• 
can be closed with a tight-fitting puncture-resistant lid, without sharps being 
able to come out, 
• 
upright and stable during use, 
• 
leak-resistant, and 
• 
properly labeled to warn of hazardous waste inside the container. 
 
When your sharps disposal container is almost full, you will need to follow your 
community guidelines for the right way to dispose of your sharps disposal 
container. There may be state or local laws about how you should throw away 

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used needles and syringes. For more information about safe sharps disposal, 
and for specific information about sharps disposal in the area that you live in, go 
to the FDA’s website at: http://www.fda.gov/safesharpsdisposal. 
 
Do not dispose of your used sharps disposal container in your household trash 
unless your community guidelines permit this. 
Do not recycle your used sharps disposal container. 
 
For more information go to www.FasenraPen.com or call 1-800-236-9933. If you 
still have questions, call your healthcare provider. 
 
Manufactured by: AstraZeneca AB, Södertälje, Sweden SE-15185 
U.S. License Number 2059 
Distributed by: AstraZeneca Pharmaceuticals LP, Wilmington, DE 19850 
FASENRA is a trademark of the AstraZeneca group of companies. 
©AstraZeneca 2019