A Phase 2b, Randomized, Double-blind, Placebo-controlled, Dose-ranging, Multi-center Study to Evaluate the Efficacy and Safety of GB001 as Maintenance Therapy in Adult Subjects With Moderate to Severe Asthma
Phase: PHASE2
Conditions: Asthma
Sponsor: GB001, Inc, a wholly owned subsidiary of Gossamer Bio, Inc.

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CLINICAL STUDY PROTOCOL 
 
 
Protocol Title:  
A Phase 2b, randomized, double-blind, placebo-controlled, 
dose-ranging, multi-center study to evaluate the efficacy and safety of 
GB001 as maintenance therapy in adult subjects with moderate to 
severe asthma 
Short Title: 
GB001 in adult subjects with moderate to severe asthma 
Protocol Number:  
GB001-2001 
Compound Number:  
GB001 
Study Phase:  
Phase 2b 
Sponsor Name: 
GB001, Inc., a wholly owned subsidiary of Gossamer Bio, Inc. 
Legal Registered 
Address: 
3013 Science Park Road, Suite 200 
San Diego, CA 92121, USA 
Regulatory Agency 
Identifier Number(s): 
 
EudraCT:        2018-002242-36 
Version: 
5.0 
Approval Date: 
16 Apr 2020 
 
 
 
 
CONFIDENTIAL 
This document contains proprietary and confidential information of GB001, Inc. Acceptance of this 
document constitutes agreement by the recipient that no previously unpublished information contained 
herein will be published or disclosed without the prior written approval of GB001, Inc. The following 
exceptions may occur under the condition that the party has agreed to keep this information confidential: 
1) disclosure of information to the extent necessary to obtain informed consent, 2) disclosure of the 
document to study personnel under your supervision who need to know the contents for conducting the 
study, and 3) disclosure of the document to appropriate Institutional Review Boards (IRBs)/Independent 
Ethics Committees (IEC). The foregoing shall not apply to disclosure required by governmental 
regulations or laws; however, GB001, Inc. shall be promptly notified of any such disclosure. 

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SPONSOR’S AUTHORIZED REPRESENTATIVE SIGNATURE PAGE 
 
 
 
 
Gossamer Bio Services, Inc. on behalf of GB001, Inc, a wholly 
owned subsidiary of Gossamer Bio, Inc. 
 
Medical Monitor Name and Contact Information will be provided separately.   

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INVESTIGATOR AGREEMENT 
GB001-2001: A Phase 2b, randomized, double-blind, placebo-controlled, dose-ranging, 
multi-center study to evaluate the efficacy and safety of GB001 as maintenance therapy in adult 
subjects with moderate to severe asthma 
I, the undersigned, have read this protocol and agree to conduct this protocol in accordance with 
ethical principles as outlined in the International Council for Harmonisation (ICH) guidelines on 
Good Clinical Practice, any applicable laws and requirements and any additional conditions 
mandated by a regulatory authority and/or Institutional Review Board/Independent Ethics 
Committee (IRB/IEC). 
I acknowledge that I am responsible for the overall study conduct and I agree to personally 
conduct or supervise the described clinical study. 
I agree to ensure that the confidential information contained in this document will not be used for 
any purpose other than the evaluation or conduct of the clinical investigation without the prior 
written consent of GB001, Inc. 
 
 
 
 
Signature 
 
 
 
Name of Investigator 
 
Date 

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Section # and Name  
Description of Change  
Brief Rationale  
compliance with good 
clinical practice (GCP), 
and minimizing the risks 
to trial integrity during the 
COVID-19 pandemic 
Global Change 
Minor revisions to text 
Administrative 
clarifications were 
incorporated, and 
typographical errors were 
corrected 
 

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TABLE OF CONTENTS 
SPONSOR’S AUTHORIZED REPRESENTATIVE SIGNATURE PAGE ...................................2 
INVESTIGATOR AGREEMENT...................................................................................................3 
PROTOCOL AMENDMENT SUMMARY OF CHANGES TABLE ............................................4 
1. 
PROTOCOL SUMMARY ..........................................................................................11 
1.1. 
Synopsis ......................................................................................................................11 
1.2. 
Schema ........................................................................................................................14 
1.3. 
Schedule of Activities .................................................................................................15 
2. 
INTRODUCTION ......................................................................................................19 
2.1. 
Study Rationale ...........................................................................................................19 
2.2. 
Background .................................................................................................................19 
2.3. 
Benefit/Risk Assessment ............................................................................................21 
2.3.1. 
GB001 Risk/Benefit Assessment ................................................................................21 
2.3.2. 
Study Design Risk/Benefit Assessment......................................................................21 
3. 
OBJECTIVES AND ENDPOINTS ............................................................................22 
4. 
STUDY DESIGN .......................................................................................................24 
4.1. 
Overall Design ............................................................................................................24 
4.1.1. 
Study Design ...............................................................................................................24 
4.1.2. 
Unscheduled Visit .......................................................................................................25 
4.2. 
Scientific Rationale for Study Design ........................................................................26 
4.2.1. 
Study Population .........................................................................................................26 
4.2.2. 
Placebo Rationale .......................................................................................................26 
4.2.3. 
Primary Endpoint Selection ........................................................................................27 
4.3. 
Justification for Dose ..................................................................................................27 
4.4. 
End of Study Definition ..............................................................................................27 
5. 
STUDY POPULATION .............................................................................................28 
5.1. 
Inclusion Criteria ........................................................................................................28 
5.2. 
Exclusion Criteria .......................................................................................................29 
5.3. 
Randomization Criteria ...............................................................................................31 
5.4. 
Screen or Run-In Failures ...........................................................................................32 
6. 
INVESTIGATIONAL PRODUCT ............................................................................33 
6.1. 
Preparation/Handling/Storage/Accountability ............................................................33 

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6.2. 
Measures to Minimize Bias: Randomization and Blinding ........................................34 
6.2.1. 
Assignment of a Subject Number ...............................................................................34 
6.2.2. 
Randomization ............................................................................................................34 
6.2.3. 
Assignment of Investigational Product Kit Numbers .................................................34 
6.2.4. 
Unblinding of an Individual Subject ...........................................................................34 
 
 
6.3. 
Investigational Product Compliance ...........................................................................35 
6.4. 
Concomitant Therapy .................................................................................................35 
6.4.1. 
Prohibited Medications Prior to the Screening Visit and Throughout the 
Study ...........................................................................................................................35 
6.4.2. 
Restricted Medications ...............................................................................................36 
6.4.3. 
Rescue Medicine .........................................................................................................36 
6.5. 
Dose Modification ......................................................................................................36 
6.6. 
Intervention After the End of the Study .....................................................................36 
7. 
DISCONTINUATION OF INVESTIGATIONAL PRODUCT AND 
SUBJECT WITHDRAWAL FROM THE STUDY ...................................................36 
7.1. 
Discontinuation of Investigational Product ................................................................36 
7.1.1. 
QTc Stopping Criteria .................................................................................................36 
7.1.2. 
Pregnancy ...................................................................................................................37 
7.2. 
Subject Withdrawal from the Study ...........................................................................37 
7.3. 
Lost to Follow up ........................................................................................................37 
8. 
STUDY ASSESSMENTS AND PROCEDURES ......................................................38 
8.1. 
Efficacy Assessments .................................................................................................40 
8.1.1. 
Asthma Worsening (Primary Endpoint) .....................................................................40 
8.1.2. 
eDiary Asthma Parameters and Alerts ........................................................................40 
8.1.3. 
Pulmonary Function Testing including Reversibility .................................................41 
8.1.4. 
Asthma Control Questionnaire-5 ................................................................................41 
8.1.5. 
Asthma Quality of Life Questionnaire- Standardized (AQLQ-S) ..............................42 
8.1.6. 
Sino-Nasal Outcome Test ...........................................................................................42 
8.1.7. 
Hair Assessment .........................................................................................................42 
8.2. 
Safety Assessments .....................................................................................................43 
8.2.1. 
Physical Examinations ................................................................................................43 
8.2.2. 
Vital Signs ..................................................................................................................43 

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8.2.3. 
Electrocardiograms .....................................................................................................43 
8.2.4. 
Clinical Safety Laboratory Assessments ....................................................................44 
8.3. 
Adverse Events, Serious Adverse Events, and Adverse Events of Interest ................44 
8.3.1. 
Time Period and Frequency for Collecting AE and SAE Information .......................44 
8.3.2. 
Method of Detecting AEs and SAEs ..........................................................................45 
8.3.3. 
Follow-up of AEs and SAEs .......................................................................................45 
8.3.4. 
Pregnancy ...................................................................................................................46 
8.3.5. 
Death Events ...............................................................................................................46 
8.3.6. 
Disease-Related Events and/or Disease-Related Outcomes Not Qualifying as 
AEs or SAEs ...............................................................................................................46 
 
 
8.4. 
Treatment of Overdose ...............................................................................................46 
8.5. 
Pharmacokinetics ........................................................................................................47 
8.6. 
Pharmacodynamics and Biomarkers...........................................................................47 
8.6.1. 
Induced Sputum ..........................................................................................................47 
8.6.2. 
Fractional Exhaled Nitric Oxide .................................................................................48 
8.6.3. 
RNA Transcriptome Research ....................................................................................48 
 
 
8.6.5. 
Blood Biomarker Analyses .........................................................................................48 
 
 
8.6.7. 
Exhaled Breath Condensate Assessment ....................................................................49 
8.7. 
Genetics ......................................................................................................................49 
9. 
STATISTICAL CONSIDERATIONS .......................................................................50 
9.1. 
Statistical Hypotheses .................................................................................................50 
9.2. 
Sample Size Determination ........................................................................................50 
9.3. 
Populations for Analyses ............................................................................................50 
9.4. 
Statistical Analyses .....................................................................................................50 
9.4.1. 
Efficacy Analyses .......................................................................................................51 
9.4.1.1. 
Primary Efficacy Analysis ..........................................................................................51 
9.4.1.2. 
Secondary Efficacy Analysis ......................................................................................51 
 
 
9.4.2. 
Safety Analyses ..........................................................................................................52 
9.4.3. 
Other Analyses ............................................................................................................52 

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9.5. 
Interim Analyses .........................................................................................................52 
9.5.1. 
Independent Data Monitoring Committee ..................................................................53 
10. 
APPENDICES ............................................................................................................54 
10.1. 
Appendix 1:  Regulatory, Ethical, and Study Oversight Considerations ...................54 
10.1.1. 
Regulatory and Ethical Considerations ......................................................................54 
10.1.2. 
Informed Consent Process ..........................................................................................54 
10.1.3. 
Data Protection ...........................................................................................................55 
10.1.4. 
Dissemination of Clinical Study Data ........................................................................55 
10.1.5. 
Data Quality Assurance ..............................................................................................55 
10.1.6. 
Source Documents ......................................................................................................56 
10.1.7. 
Study and Site Closure................................................................................................57 
10.1.8. 
Publication Policy .......................................................................................................57 
10.2. 
Appendix 2:  Clinical Laboratory Tests ......................................................................58 
10.3. 
Appendix 3:  Adverse Events: Definitions and Procedures for Recording, 
Evaluating, Follow up, and Reporting ........................................................................60 
10.3.1. 
Definition of AE .........................................................................................................60 
10.3.2. 
Definition of SAE .......................................................................................................61 
10.3.3. 
Adverse Events of Interest ..........................................................................................62 
10.3.4. 
Recording and Follow Up of Adverse Events and Serious Adverse Events ..............62 
10.3.5. 
Reporting of SAEs ......................................................................................................65 
10.4. 
Appendix 4:  Contraceptive Guidance and Collection of Pregnancy 
Information .................................................................................................................66 
10.5. 
Appendix 5:  Genetics ................................................................................................70 
10.6. 
Appendix 6:  Liver Safety - Actions and Follow-up Assessments .............................71 
10.7. 
Appendix 7:  Daily Asthma Symptom Score .............................................................74 
10.8. 
Appendix 8:  Prohibited Medications and Treatments ...............................................75 
10.9. 
Appendix 9:  Restricted Medications and Treatments ................................................77 
10.10. 
Appendix 10:  Estimated Clinical Comparability of Medium and High Doses 
of Inhaled Corticosteroids ...........................................................................................78 
10.11. 
Appendix 11:  Assessment of Hair Loss.....................................................................79 
10.12. 
Appendix 12:  Guidance to Address a Pandemic or Other Global Health 
Emergencies and Potential Impact on the Clinical Study ...........................................80 
10.13. 
Appendix 13:  Abbreviations ......................................................................................81 
10.14. 
Appendix 14: Protocol Amendment History ..............................................................84 

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11. 
REFERENCES ...........................................................................................................91 
 
LIST OF TABLES 
Table 1: 
Investigational Product Formulation by Treatment Group .........................................33 
Table 2: 
Protocol-Required Safety Laboratory Assessments ...................................................58 
Table 3: 
Liver Safety Laboratory Assessments ........................................................................59 
Table 4: 
Liver Chemistry Criteria Requiring Additional Monitoring with Possible 
Interruption of Investigational Product .......................................................................71 
Table 5: 
Liver Chemistry Criteria Requiring Investigational Product Interruption and 
Additional Monitoring ................................................................................................72 

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1. 
PROTOCOL SUMMARY 
1.1. 
Synopsis 
Protocol Title: A Phase 2b, randomized, double-blind, placebo-controlled, dose-ranging, 
multi-center study to evaluate the efficacy and safety of GB001 as maintenance therapy in adult 
subjects with moderate to severe asthma 
Short Title: GB001 in adult subjects with moderate to severe asthma 
Rationale: 
GB001 is a potent and highly selective oral prostaglandin D2 receptor (DP2) antagonist. DP2 is 
expressed on a variety of cells implicated in the allergic process including eosinophils and 
epithelial cells (Kupczyk, 2017; Singh, 2017). GB001 is being developed as a once daily oral 
add-on maintenance treatment for moderate to severe eosinophilic asthma. 
The purpose of this Phase 2b study is to evaluate the efficacy, safety, pharmacokinetics, and 
pharmacodynamics of 3 GB001 dose levels compared with placebo in subjects with moderate to 
severe asthma and an eosinophilic phenotype. The study will assess the efficacy of GB001 
relative to placebo in reducing asthma worsening when added to standard of care (SOC) asthma 
maintenance therapy.  

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Overall Design: 
This is a Phase 2b, randomized, double-blind, placebo-controlled, dose-ranging, multi-center 
study to evaluate the efficacy and safety of GB001 as maintenance therapy in a moderate to 
severe eosinophilic asthma population. GB001 will be added to the subject’s standard-of-care 
asthma treatment. 
An interim analysis to inform further development of GB001 will be conducted after the first 
320 subjects have completed the study or have prematurely withdrawn from the study. 
A schematic of the study design is presented in Section 1.2. 
Disclosure Statement: 
This is a parallel group treatment study with 4 arms that is participant, Investigator, and Sponsor 
blinded. 
Number of Participants: 
This study will randomize approximately 480 subjects, with approximately 120 subjects per 
treatment group. 
Intervention Groups and Duration: 
Treatment groups: 
• GB001 60 mg daily 
• GB001 40 mg daily 
• GB001 20 mg daily 
• Matching placebo daily 
Total duration for study participation per subject is up to 34 weeks (includes a Screening visit; 
followed by a 2-week to 6-week Run-in period to allow for collection of baseline eDiary data; a 
24-week Double-Blind, Placebo-Controlled period; and 4-week Follow-up period). 
Independent Data Monitoring Committee (IDMC): Yes 

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1.2. 
Schema 
 
 

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2. 
INTRODUCTION 
2.1. 
Study Rationale 
GB001 is a potent and highly selective oral prostaglandin D2 receptor (DP2) antagonist. DP2 is 
expressed on a variety of cells implicated in the allergic process including eosinophils and 
epithelial cells (Kupczyk, 2017; Singh, 2017). GB001 is being developed as a once daily oral 
add-on maintenance treatment for moderate to severe eosinophilic asthma. 
The purpose of this Phase 2b study is to evaluate the efficacy, safety, pharmacokinetics, and 
pharmacodynamics of 3 GB001 dose levels compared with placebo in subjects with moderate to 
severe asthma and an eosinophilic phenotype. The study will assess the efficacy of GB001 
relative to placebo in reducing asthma worsening when added to standard of care (SOC) asthma 
maintenance therapy. 
2.2. 
Background 
More than 300 million people around the globe are diagnosed with asthma, a heterogenous 
chronic disease characterized by variable airflow obstruction and symptoms of cough, wheeze, 
and dyspnea. Inhaled corticosteroids (ICS) are the cornerstone of asthma maintenance therapy, 
with or without additional controllers (GINA, 2018). However, not all patients have a complete 
resolution of the underlying inflammation, and some continue to have severe asthma 
exacerbations. Prevention of severe asthma exacerbations is of utmost importance in the 
treatment of asthma. The significance of preventing severe asthma exacerbations is highlighted 
as 1 of the 7 key conclusions in the recent Lancet Commission Report (Pavord, 2018). Severe 
exacerbations create anxiety for the patient and their families, place stress on the healthcare 
system, and may result in more rapid decline in lung function (Reddel, 2009; O'Byrne, 2011; 
Ortega, 2018). From a societal perspective, asthma exacerbations result in millions of days of 
lost work each year (Botturi, 2011; Catley, 2011). The occurrence of asthma worsening or severe 
asthma exacerbations (asthma attack) is not infrequent. Approximately 45% of working adults in 
the United States with a diagnosis of asthma experienced at least one episode over the 5-year 
period from 2011-2016 (Mazurek, 2018). In summary, there continues to be an unmet medical 
need to provide novel therapies to reduce asthma worsening and severe asthma exacerbations. 
New biologics have recently entered the market to address, in part, the unmet medical need. 
However, these medications are given by injection, which currently requires a patient to visit a 
clinic every 2 to 8 weeks and may require multiple injections per dose. In addition, these 
medications may not be available to every patient who needs them. Lastly, biologic medications 
are restricted to patients who require Global Initiative for Asthma (GINA) guideline step 5 
treatment (GINA, 2018) and have exhausted other asthma therapies. It would be beneficial to 
have an effective therapy for reducing severe exacerbations as an option at earlier GINA steps. 
The class of compounds known as DP2 antagonists which act through the DP2 receptor may offer 
the potential to become an add-on oral maintenance therapy at GINA step 4 or earlier to decrease 
the occurrence of asthma exacerbations. DP2 has been implicated as a pathway that has a direct 
effect upon specific cell types that are associated with severe asthma, specifically mast cells and 
eosinophils. Importantly, it has been demonstrated that asthma patients with more severe disease 

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or a history of an exacerbation in the prior year had upregulation of the prostaglandin D2 (PGD2)-
DP2 pathway and had the highest expression of the DP2 receptor in bronchial biopsy samples 
(Fajt, 2013). It is anticipated that GB001 will reduce recruitment and activation of airway 
eosinophils, with consequent reduction in airway inflammation including effects on fractional 
exhaled nitric oxide (FeNO). In a recent post-hoc analysis of 36 subjects (ADC3680-04) with 
mild to moderate atopic asthma receiving a total daily dose of fluticasone propionate ≤ 500 μg or 
equivalent, who were randomized (2:1) to 30 mg of GB001 or placebo once daily for 28 days, 
lung function was analyzed by baseline FeNO (< 35 and ≥ 35 ppb) and blood eosinophil 
(< 200 and ≥ 200/µL) subgroups (Ortega, 2019a; Ortega, 2019b). In the overall population, 
GB001 had a favorable effect on forced expiratory volume in 1 second (FEV1) at Day 28 
(difference in mean change for GB001 versus placebo of 102 mL, n = 36). Changes in FEV1 
were also observed in the high baseline FeNO (n = 14) and high baseline eosinophil (n = 16) 
subgroups (differences of 207 mL and 81 mL, respectively). These results suggest that GB001 
favorably influences lung function in subjects with markers of eosinophilic inflammation. 
Two important studies with the oral DP2 antagonist fevipiprant provide further support for the 
development of this class of compounds for the reduction of asthma exacerbations in patients 
with severe asthma and markers of eosinophilic inflammation. In the first study conducted by 
Gonem et al, fevipiprant (compared to placebo) significantly reduced eosinophilic inflammation 
as measured by a reduction in sputum eosinophils in patients receiving ICS and having either an 
ACQ-7 score of at least 1.5 at randomization or a severe asthma exacerbation in the prior year 
(Gonem, 2016). The magnitude of reduction in sputum eosinophils with fevipiprant treatment for 
12 weeks is consistent with that of the biologic mepolizumab (Haldar, 2009; Pavord, 2012). The 
second Phase 2 study is a large dose-ranging study that evaluated the effect of a wide range of 
fevipiprant doses in comparison to placebo and montelukast in a population with moderate to 
severe asthma. The primary efficacy outcomes were based upon FEV1 which demonstrated 
improvements in lung function from baseline over 12 weeks. Additionally, a post-hoc analysis 
investigated the reduction in asthma worsening/exacerbations in over 1000 patients. Despite the 
short treatment duration of 12 weeks, a trend for reduction of asthma worsening and asthma 
exacerbation events was seen when all doses (1 mg to 450 mg) were pooled (Bateman, 2017). 
The effect of GB001 in reducing asthma worsening has been studied in a Phase 2 study in 
Japanese subjects (Study PTR-36-201). This study enrolled subjects who were taking a 
medium-dose ICS or medium-dose ICS/LABA. Prior to start of the Run-in, subjects taking ICS/ 
long-acting beta agonist (LABA) were required to switch to ICS only. At baseline, subjects 
evaluated for efficacy had a mean ACQ score of 0.795 and a mean eosinophil count of 319 
cells/µL. Following a Run-in period, subjects were randomized to double-blind treatment with 
GB001 20 mg, GB001 5 mg, or placebo for 16 weeks. During the first 8 weeks on study (ie, 4-
week Run-in and 4 weeks of the double-blind treatment period), background ICS treatment was 
tapered and ultimately withdrawn. Subjects then continued for an additional 12 weeks on 
monotherapy. The proportion of subjects with asthma worsening was significantly lower in the 2 
GB001 groups (32.7% GB001 5 mg, 20.8% GB001 20 mg) compared with the placebo group 
proportion of 52.8% (p < 0.05 for both dose levels). Collectively, these data along with the data 
from fevipiprant support further investigation of GB001 to reduce asthma exacerbations. 
The results of other GB001 clinical studies are available in the Investigator’s Brochure. 

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2.3. 
Benefit/Risk Assessment 
2.3.1. 
GB001 Risk/Benefit Assessment 
GB001, an oral DP2 antagonist, is being developed as a maintenance therapy in asthma. Despite 
the recent availability of injectable biologics to manage asthma patients with poor control and 
exacerbations, there continues to be a paucity of oral agents to help manage and control asthma. 
The mechanism of GB001 is to antagonize the DP2 receptor and thereby reduce the T helper cell 
type 2 (Th2) response while affecting other cells relevant in the inflammatory and allergic 
cascade with corresponding improvements in asthma control, lung function and exacerbations 
(Hall, 2015; Gonem, 2016; Bateman, 2017). Ultimately these physiologic effects could result in 
an improvement in the overall quality of life of patients with moderate to severe asthma. 
As of 29 August 2019, a total of 459 subjects have received at least 1 dose of GB001 at any dose 
level. Drug induced liver injury is considered a potential risk of GB001 due to the occurrence of 
two Hy’s Law cases, one was a liver disorder (preferred term) in a healthy subject at 160 mg in 
Study PTR-36-101 and one was hepatic enzyme increased (preferred term) in the current study 
which remains blinded. Details are provided in the IB. Liver monitoring is critical for the safe 
management of subjects. Investigators should have a low threshold for discontinuing study drug 
with any suspicion of drug-induced liver injury. Safety will be closely monitored by the Sponsor 
and the Independent Data Monitoring Committee (IDMC). 
2.3.2. 
Study Design Risk/Benefit Assessment 
This study is designed to assess the effect of GB001 on asthma worsening, while maintaining 
asthma controller therapy. Since this study employs an add-on therapy design, subjects will be 
maintained on their stable SOC regimen throughout the study. 
To minimize the potential risk to subjects, stringent criteria are utilized during screening to 
exclude subjects with a history of significant other pulmonary disease, liver disease or other 
comorbidities that could impact subjects’ safety. In addition, subjects will be closely monitored 
with regards to liver function following current guidelines. All subjects will be closely monitored 
throughout the study through daily home morning peak expiratory flow (PEF) and eDiary 
monitoring. Alerts are programmed into the eDiary that trigger in the event of potential loss of 
asthma control. Upon receiving an alert, subjects will be instructed to contact their study 
physician and if necessary go to the site for further evaluation.  
Exacerbations are recognized as a common clinical manifestation in patients with severe asthma 
(GINA, 2018). Currently, management of acute exacerbations includes high doses of systemic 
corticosteroids, which is coupled with the known health risks associated with steroids 
(Dalal, 2016). This study offers the potential benefit for subjects receiving GB001 to experience 
fewer exacerbations and consequently have a reduction in the total cumulative dose of systemic 
corticosteroids (eg, prednisone), thereby minimizing the risk of acute systemic side effects of 
corticosteroids. As an additional potential benefit, all participating subjects on active or placebo 
will be frequently and closely monitored during the duration of the study with optimized 
standard of care. Furthermore, in patients who complete the study, an extension follow-up study 
may be offered in which all subjects will receive GB001. 

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4. 
STUDY DESIGN 
4.1. 
Overall Design 
This is a Phase 2b, randomized, double-blind, placebo-controlled, dose-ranging, multi-center 
study to evaluate the efficacy and safety of GB001 as maintenance therapy in a moderate to 
severe eosinophilic asthma population. GB001 will be added to the subject’s standard-of-care 
asthma treatment. 
An interim analysis to inform further development of GB001 will be conducted after the first 
320 subjects have completed the study or have prematurely withdrawn from the study (see 
Section 9.5). 
A schematic of the study design is presented in Section 1.2. 
4.1.1. 
Study Design 
The study will commence with a Screening visit (Visit 1), at which informed consent will be 
obtained and inclusion and exclusion criteria will be assessed. Informed consent may be obtained 
prior to the day of the Screening visit to allow for medication washouts or for other logistical 
reasons such as obtaining documentation of exacerbations or historical reversibility, if necessary. 
All other screening procedures should be completed on the day of the Screening visit. Subjects 
not meeting the eligibility criteria will be deemed screen failures and will not continue 
participation in the study (see Section 5.4). Eligible subjects will enter a Run-in period of a 
minimum of 2 weeks and a maximum of 6 weeks and will remain on their SOC regimen. The 
Run-in period commences with completion of all Screening visit procedures and concludes at the 
Randomization visit. During the Run-in period, subjects will capture PEF and asthma symptoms 
in an eDiary daily. Subjects who experience an asthma exacerbation during the Run-in period 
will receive appropriate treatment and remain in the Run-in period until their asthma status has 
returned to baseline status for at least 1 week. Subjects who are not able/eligible to be 
randomized due to ongoing asthma exacerbation at the end of the Run-in period will be 
discontinued from study participation and be labeled as Run-in failures. Subjects will remain on 
their SOC therapy during the Run-in period. 
At Visit 2 (Week 0, Day 1), subjects who meet the randomization eligibility criteria will be 
randomized in a 1:1:1:1 ratio to receive one of the following double-blind treatments for 
24 weeks: 
• GB001 60 mg daily 
• GB001 40 mg daily 
• GB001 20 mg daily 
• Matching placebo daily 
Randomization will be stratified by baseline ICS dose (medium or high, as defined in 
Appendix 10; Section 10.10) and country. 
The first dose of double-blind investigational product (IP) will be administered in the clinic on 
Day 1. All subsequent doses will be taken orally at home at bedtime on an empty stomach. 

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Following initiation of IP, subjects will visit the clinic for assessments at Weeks 2, 3, and 4, 
followed by visits approximately every 4 weeks for an additional 5 visits. Subjects should remain 
on their stable current SOC therapy (ie, medium or high dose ICS plus additional controller 
therapy) through the duration of their time on study (refer to Schedule of Activities, Section 1.3). 
Subjects will be provided with an eDiary which is programmed to alert the subject of potential 
asthma worsening: 
1. On 2 consecutive days, AM PEF ≤ 75% of mean AM PEF measured over the last 7 days 
of the Run-in period 
2. Increase in rescue medication use of ≥ 6 puffs/day (last 24 hours) on 2 consecutive days 
compared to mean use over the last 7 days of the Run-in period 
3. Nighttime awakening due to asthma symptoms requiring rescue medication for at least 2 
of 3 successive nights 
4. An asthma symptom score of 4 for at least 2 of 3 successive days.  
Upon receiving an alert, the subject should contact the site staff as soon as practical to assess the 
subject’s asthma status. The subject may be asked to return to the clinic when necessary to have 
their asthma status evaluated. 
Subjects who permanently discontinue IP will be requested to attend the Early Discontinuation 
of IP visit and will be strongly encouraged to complete any remaining study visits as per the 
Schedule of Activities (SoA; Section 1.3). Subjects who permanently discontinue IP and 
continue in the study will complete the Early Discontinuation of IP visit at the time of IP 
discontinuation and then return for the next visit in the Double-Blind, Placebo-Controlled visit 
sequence. At the visits subsequent to the Early Discontinuation of IP visit, study procedures will 
be completed except for dispensation/return of IP. Subjects who withdraw from the study, 
regardless of the reason, will be requested to return to the clinic to complete the Early 
Withdrawal (EW) from Study visit. All subjects who remain on IP through and including Visit 9 
(Week 24) or who complete the EW from Study visit will be asked to return for a Follow-up visit 
approximately 4 weeks after their last dose of IP to assess subject safety. 
Total duration for study participation per subject is up to 34 weeks (includes a Screening visit, 
followed by a 2-week to 6-week Run-in period to allow for collection of baseline eDiary data; a 
24-week Double-Blind, Placebo-Controlled period; and 4-week Follow-up period). 
4.1.2. 
Unscheduled Visit 
There may be a need to have a subject return to clinic for an unscheduled visit for a variety of 
reasons, including but not limited to: repeat of a lab test, replacement of IP kit, evaluation of an 
adverse event (AE), or evaluation of asthma status. Any procedure that is conducted during a 
regularly scheduled on-treatment visit may be performed at an unscheduled visit. 
If a subject returns to the clinic between regularly scheduled visits to assess asthma status, the 
following should be conducted: 
• Review eDiary data to confirm if asthma worsening has occurred; and 
• Have the subject complete the ACQ-5 and spirometry if possible to determine if 
asthma worsening has occurred. 

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4.2. 
Scientific Rationale for Study Design 
4.2.1. 
Study Population 
The target population is patients with moderate to severe asthma who are currently receiving 
GINA step 4 or 5 therapy and have evidence of eosinophilic inflammation. Reducing 
eosinophilic inflammation within the lungs, assessed by measuring sputum eosinophils, has been 
associated with a reduction in asthma exacerbations (Haldar, 2009; Pavord, 2012). It is 
anticipated that GB001, as a DP2 antagonist, will reduce sputum eosinophilia and consequently 
asthma exacerbations. As measurement of sputum eosinophils is cumbersome and requires sites 
experienced with this procedure to obtain appropriate samples, a surrogate measure of lung 
eosinophils, namely peripheral blood eosinophils, will be used in this study. The cut-off 
threshold of 250 cells/µL has been selected for this study as it is predicted to have a sensitivity of 
84% and a specificity of 91% to differentiate less than versus ≥ 3% sputum eosinophils 
(Wagener, 2015). 
Based upon regulatory guidance, patients with a history of asthma exacerbations should be 
recruited in studies where the primary endpoint is exacerbation reduction (EMA, 2015). Patients 
with a history of exacerbations are more likely to experience future exacerbations. Therefore, 
this study will be recruiting subjects with a history of at least 1 asthma exacerbation in the 
previous 12 months. 
In addition, DP2 antagonists might have an effect in a subset of subjects with inflammation 
beyond the lower airways such as upper airways and skin. Thus, exploratory assessments 
targeting these tissues will evaluate additional beneficial effects as a result of treatment with 
GB001. 
4.2.2. 
Placebo Rationale 
A placebo-controlled design is necessary because asthma is a disease that waxes and wanes over 
time, and the endpoint of asthma worsening has a subjective component. Therefore, it is 
important to be able to differentiate the efficacy of GB001 compared to the “placebo effect,” 
which may be as high as 30% to 50% depending on the endpoint chosen (Castro, 2007). 
Importantly, placebo-controlled studies require fewer subjects than active-controlled studies to 
demonstrate superiority of the experimental treatment. In addition, comparisons between the 
GB001 and placebo treatment groups will facilitate differentiation of the GB001 safety profile 
from that of the subject’s SOC therapy. Lastly, a placebo group, as opposed to an active control, 
will help to understand whether the occurrence of an AE in a GB001 group is different from that 
which would occur in the asthma population in the absence of GB001. 
An IDMC will periodically convene to review unblinded efficacy and safety data. The first 
IDMC meeting at which results are reviewed will occur after approximately 50 subjects have 
been randomized and have completed 12 weeks on study or within 12 months of the first subject 
randomized. 
A placebo-controlled design for this study is consistent with the European Medicines Agency 
regulatory guideline on the clinical investigation of IP for the treatment of asthma (EMA, 2015), 
wherein the following statement is made: “If the drug is not intended to be substituted for ICSs, 
add-on designs where the new drug is compared with placebo on top of standard background 

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medication are required.” As such, GB001-2001 includes a placebo group in addition to the 
subject’s SOC therapy. 
4.2.3. 
Primary Endpoint Selection 
The use of proportion of subjects with worsening of asthma as an endpoint has been employed 
successfully in previous asthma studies (Wenzel, 2013; Castro, 2014), including a Phase 2 study 
with GB001 (PTR-36-201). This composite endpoint has the potential to reduce the sample size 
and duration of a study relative to an endpoint of severe exacerbations, while providing a 
clinically meaningful output. At the same time, this allows fewer subjects to be exposed to an 
investigational product in development when the efficacy and safety have not been fully 
established. The parameters included in the asthma worsening composite endpoint include 
changes in lung function (FEV1 and PEF), rescue medication use, asthma control and symptoms. 
These markers of asthma control are closely related to signs and symptoms associated to 
exacerbations. 
4.3. 
Justification for Dose 
This study will assess the dose-response relationship of 3 doses of GB001 (60 mg, 40 mg, and 
20 mg) in adult subjects with moderate to severe asthma. 
The GB001 40 mg dose was selected based on the anticipated pharmacokinetics (PK) and 
exposure levels extrapolated from the results of two Phase 2 studies with GB001 (Study PTR-36-
201 and ADC3680-07) and based on prior efficacy and safety results from these studies. In 
Study PTR-36-201, GB001 20 mg and 5 mg doses were evaluated in an asthma treatment 
withdrawal design. Both doses of GB001 were effective in decreasing the proportion of subjects 
with asthma worsening/exacerbations as compared to placebo, with the 20 mg dose producing a 
larger treatment effect (20 mg: 20.8%; 5 mg: 32.7%; placebo: 52.8%). In addition, only the 
20 mg dose demonstrated statistical significance for the endpoints of asthma control (ACQ-5) 
and time to asthma worsening relative to placebo. No improvements in lung function were 
observed, while less worsening of lung function was seen in the GB001 groups compared to 
placebo. A comparable safety profile was observed across all treatment arms (including placebo) 
in this study. Based on this data, the 40 mg dose has been selected for the current study. 
To characterize the dose-response curve, 1 dose level below and 1 dose level above the 40 mg 
dose are included in the current study. The 20 mg dose has been included as a potentially 
suboptimal dose based on data generated from a Phase 2 study of GB001 versus placebo 
(Study ADC3680-07). This study found that GB001 20 mg daily produced some efficacy, as 
measured by improvements in ACQ scores, but this dose level did not result in improvements in 
lung function. The 60 mg dose is included to assess whether greater efficacy may be achieved 
beyond that of the 40 mg dose, since no improvements have been seen in lung function with 
lower doses to date. 
4.4. 
End of Study Definition 
Subjects will be regarded to have completed the study if he/she completes the Week 24 visit. The 
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5. 
STUDY POPULATION 
Prospective approval of protocol deviations to recruitment and enrollment criteria, also known as 
a protocol waiver or exemption, is not permitted. 
5.1. 
Inclusion Criteria 
To confirm eligibility, a review of each subject’s medical records should be performed prior to 
the subject entering the Run-in period. Prior to randomization, additional randomization criteria 
(including blood eosinophils ≥ 250 cells/µL; Section 5.3) must be met. 
Subjects are eligible to enter the Run-in period only if all the following criteria are met: 
1. Informed Consent: Capable of giving signed informed consent which includes 
compliance with the requirements and restrictions listed in the informed consent form 
(ICF) and in this protocol. 
2. Age: ≥ 18 and < 75 years of age at the time of Screening visit. 
3. Gender: Males or females: 
a. Women of childbearing potential (WOCBP) must use an acceptable method of 
contraception (see Appendix 4, Section 10.4) at least 1 month prior to Screening 
through 28 days after the last dose of IP. 
4. Weight: at least 40 kg. 
5. Diagnosis of asthma:  A diagnosis of asthma by a physician according to GINA 
guidelines of at least 12 months prior to Screening. 
6. ICS plus additional controller: Subjects with a documented requirement for regular 
treatment with medium or high dose ICS and at least one other controller medication for 
at least 12 months prior to Visit 1. Subjects must maintain a stable ICS dose regimen 
during the 4 weeks prior to Visit 1. 
a. Medium dose ICS is defined as an ICS dose equivalent to fluticasone propionate 
> 250 to 500 mcg/day and high dose is defined as an  ICS dose equivalent to 
fluticasone propionate > 500 mcg/day (for equivalent ICS doses see Appendix 10, 
Section 10.10) 
b. An additional controller medication such as LABA, long-acting muscarinic antagonist 
(LAMA), or leukotriene receptor antagonist (LTRA).  
7. FEV1: a pre-bronchodilator FEV1 of ≤ 85% of predicted normal. 
8. Reversibility/Airway Hyperresponsiveness:  
• At least 12% in FEV1 following 4 puffs of albuterol 400 μg ex-US (360 μg US) or 1 
equivalent nebulized dose/salbutamol 100 mcg at Screening. Reversibility is to be 
assessed in all subjects at Screening. 
•  If a subject does not reverse at least 12% at Screening, the site may submit historical 
documentation of one of the following for review and approval by the Medical 
Monitor: 
− reversibility in the 24 months prior to Screening visit, OR 

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− airway hyperresponsiveness demonstrated by a positive methacholine, histamine, 
or mannitol challenge. 
9. Evidence of uncontrolled asthma: demonstration of uncontrolled asthma by one of the 
following: 
a. Previously confirmed history of 2 or more asthma exacerbations requiring treatment 
with systemic corticosteroids in the 12 months prior to Screening visit. 
OR 
b. Previously confirmed history of 1 asthma exacerbation requiring treatment with 
systemic corticosteroids in the 12 months prior to Screening visit and ACQ-5 of ≥ 1.5 
at Screening visit. 
10. Are willing and able to comply with the requirements for participation in the study. 
5.2. 
Exclusion Criteria 
Subjects are excluded from the study if any of the following criteria apply: 
1. Smoking history: Current smokers (any substance), or former smokers with a smoking 
history of ≥ 10 pack-years [(number of cigarettes per day/20) x number of years smoked]. 
A former smoker is defined as a subject who quit smoking at least 6 months prior to 
Screening visit. This includes electronic cigarettes and vaping. 
2. Concurrent Respiratory Disease: Presence of a known pre-existing clinically important 
lung condition other than asthma. This includes current infection, active tuberculosis 
infection, bronchiectasis, pulmonary fibrosis, bronchopulmonary aspergillosis or 
diagnoses of emphysema or chronic bronchitis (chronic obstructive pulmonary disease 
other than asthma) or a history of lung cancer. 
3. Malignancy: A current malignancy or previous history of cancer in remission for less 
than 5 years prior to Screening. (Subjects will not be excluded if they had localized 
carcinoma of the skin that was resected for cure.) 
4. Liver Disease: Known pre-existing liver disorders (ie, non-alcoholic fatty liver disease 
(NALFD) or Gilbert’s syndrome), or unstable liver disease (as defined by the presence of 
ascites, encephalopathy, coagulopathy, hypoalbuminemia, esophageal or gastric varices 
or persistent jaundice), cirrhosis, or known biliary abnormalities. 
5. Other Concurrent Medical Conditions: Known, pre-existing clinically significant 
endocrine, autoimmune, metabolic, neurological, renal (calculated creatinine clearance 
< 60 mL/min), gastrointestinal, hepatic, cardiovascular, hematological, or any other 
system abnormalities that are uncontrolled with standard treatment. 
6. Eosinophilic Disease: Subjects with any other condition that could lead to elevated 
eosinophils such as hypereosinophilic syndrome, including eosinophilic granulomatosis 
with polyangiitis. 
7. ECG Assessment: QTcF ≥ 450 msec for males or QTcF ≥ 470 msec for females at the 
Screening visit. If QTcF is above the prespecified limit and there are no other clinically 

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significant abnormalities, the assessment can be repeated in triplicate and the three results 
will be averaged for eligibility. 
8. Alcohol/Substance Abuse: A history or suspected history of alcohol misuse or substance 
abuse, including marijuana, within 12 months prior to Screening visit. 
9. Immunodeficiency: A known immunodeficiency, including that due to human 
immunodeficiency virus (HIV), other than that explained by systemic corticosteroid use. 
10. Investigational medications: Subjects who have received treatment with an 
investigational medication within the past 30 days or within 5 half-lives of the 
medication, whichever is longer, prior to Screening visit. (This also includes 
investigational formulations of marketed products.) 
11. DP2 (CRTh2) antagonist studies: Participated in another DP2 (CRTh2) antagonist study 
in the 12 months prior to Screening visit or known prior intolerance or inadequate 
response in a prior DP2 antagonist study. 
12. Receiving prohibited medications or treatments: (refer to Appendix 8, Section 10.8, 
for more details) 
a. Regular use of systemic corticosteroids or immunosuppressive therapies including 
methotrexate or azathioprine 
b. Monoclonal antibodies used in the treatment of asthma such as reslizumab, 
mepolizumab, omalizumab or benralizumab 
c. Medications, food or drink that are moderate or strong CYP3A4 inhibitors or inducers 
d. Medications that have the potential for interaction with GB001 
e. Bronchial thermoplasty and radiotherapy are excluded in the 12 months prior to 
Screening 
13. Prior participation in a study with GB001: Subjects who previously participated in a 
study with GB001 (also named PTR-36 or ADC3680) are not eligible for this study. 
14. Hypersensitivity: A known sensitivity to GB001 or any of its excipients. Patients with 
rare hereditary problems of galactose intolerance, the Lapp lactase deficiency, or 
glucose-galactose malabsorption are not eligible for this study. Subjects with 
mild-moderate lactose intolerance are not excluded. 
15. Pregnancy: Subjects who are pregnant or breastfeeding. Subjects should not be enrolled 
if they are planning to become pregnant during the time of study participation. A serum 
pregnancy test is required of all females of child-bearing potential at Screening. 
16. Adherence: Subjects who have a known lack of adherence to controller medications. 
17. Body Mass Index (BMI): BMI is ≥ 40 kg/m2. 
18. Have any other condition or reason that, in the opinion of the Investigator, would prohibit 
the subject from participating in the study, including participation in another clinical trial 
while participating in this study. 

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5.3. 
Randomization Criteria 
At the end of the Run-in period, study subjects must fulfill the following criteria to be 
randomized to study treatment: 
1. Eosinophilic asthma: A peripheral blood eosinophil count of ≥ 250 cells/µL measured at 
the Screening visit. NOTE: In a subject with prior evidence of an eosinophilic 
phenotype, as assessed by the Investigator, an eosinophil count < 250 may be repeated 
during Run-in upon approval by the Medical Monitor. 
2. FEV1: The morning percent predicted FEV1 must be ≤ 85% of the predicted normal at 
both the Screening visit and Randomization visit. 
3. FEV1 overread: The Screening visit overread by vendor must confirm eligibility was 
met. 
4. eDiary compliance: Compliance with completion of the eDiary as defined as: 
• Completion of rescue medication use question on 4 or more of the last 7 days 
immediately prior to Visit 2 (includes the morning of Visit 2). 
AND 
• Completion of AM PEF on 4 or more of the last 7 mornings immediately prior to 
Visit 2 (includes the morning of Visit 2). 
• Note: If the eDiary was completed on < 4 days due to technical challenges, the Visit 
2 may be delayed up to an additional 3 days to allow for completion of the eDiary 
parameters above. 
5. ACQ-5: The ACQ-5 assessment has been completed in the eDiary in clinic during the 
Randomization visit. 
6. Laboratory abnormality: No evidence of clinically significant abnormality in the 
hematological, biochemical, or urinalysis at Screening visit, as judged by the 
Investigator.  
7. Hepatitis status: No evidence of chronic hepatitis B or C, as evidenced by a negative 
hepatitis B surface antigen (HbsAg) or hepatitis C test at the Screening visit. Note: if 
hepatitis C antibody test is positive or indeterminate at screening, the confirmatory test 
result must be negative for Hepatitis C. 
8. Chemistry and hematology obtained at Screening visit: 
• ALT must be < 2x the upper limit of normal (ULN) 
• AST must be < 2x ULN 
• Alkaline phosphatase must be < 2x ULN 
• Bilirubin must be < 1x ULN 
• Absolute eosinophil count must be < 1,500 cells/μL 
• White blood cell count must be < 15,000 cells/μL 

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9. ECG overread: The screening ECG overread confirms the QTcF interval is < 450 msec 
for males or QTcF < 470 msec for females.  
10.  Asthma exacerbation: 
Subjects who experience an asthma exacerbation during the Run-in period should have 
their Randomization visit (Visit 2) delayed until the Investigator considers the subject has 
returned to their baseline asthma status. If a 6-week Run-in period has elapsed before the 
subject is back to baseline status, then the subject will be considered a Run-in failure. An 
asthma exacerbation is defined as worsening of asthma requiring the use of systemic 
corticosteroids for at least 3 days, hospitalization, or an Emergency Department visit. 
11. Compliance with the subject’s SOC asthma therapy as evidenced by: 
• No changes in the dose or regimen of the Run-in asthma therapy (except for treatment 
of an asthma exacerbation). 
AND 
• Subjects must have demonstrated ≥ 75% compliance with their SOC therapy during 
Run-in. 
12.  Pregnancy test:  For WOCBP, both the serum pregnancy test at the Screening visit and 
the urine pregnancy test at Visit 2 must be negative. 
5.4. 
Screen or Run-In Failures 
Subjects will be assigned a subject number at the time of signing the ICF. Subjects who do not 
enter the Run-in period will be labeled as Screen failures. 
Subjects who enter the Run-in period but are not randomized will be designated as Run-in 
failures, even if they complete the Run-in period. 
A minimal set of Screen failure/Run-in failure information is required to ensure transparent 
reporting of Screen/Run-in failure subjects to meet the Consolidated Standards of Reporting 
Trials (CONSORT) publishing requirements and to respond to queries from regulatory 
authorities. Minimal information includes demography, Screen/Run-in failure details, eligibility 
criteria, and any serious adverse event (SAE). 
Subjects who are not randomized may be eligible to rescreen upon approval by the Medical 
Monitor. A new subject number will be assigned if approved to rescreen. 

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6. 
INVESTIGATIONAL PRODUCT 
Table 1: 
Investigational Product Formulation by Treatment Group 
Treatment 
Groups 
GB001 60 mg 
GB001 40 mg 
GB001 20 mg 
Placebo 
Dose 
Formulation 
Film-Coated 
Tablet 
Film-Coated 
Tablet 
Film-Coated 
Tablet 
Film-Coated 
Tablet 
Unit Dose 
Strength(s) 
3 x 20 mg tablet 
2 x 20 mg tablet 
and 
1 x placebo tablet 
1 x 20 mg tablet 
and 
2 x placebo tablet 
3 x placebo tablet 
Dosage Level(s) 
60 mg at bedtime 
40 mg at bedtime 
20 mg at bedtime 
Placebo at 
bedtime 
Route of 
Administration 
and Instructions 
Oral on an empty 
stomach 
Oral on an empty 
stomach 
Oral on an empty 
stomach 
Oral on an empty 
stomach 
Packaging and 
Labeling 
GB001 and Placebo film-coated tablets will be packaged in blinded dosing kits. 
Each kit will consist of a labeled wallet containing 2 blister cards with 24 tablets 
each (ie, 48 tablets per kit), which will provide sufficient doses for 16 days of 
treatment (14 days + 2 days for the visit window). Individual kits have been 
packaged to deliver 3 tablets per day of the appropriate combination of 20 mg and 
placebo tablets as described in “unit dose strength” above. Subjects will receive 1 
or 2 kits at each visit based on the timing of the subsequent visit. The kits will be 
labeled as required per country requirement. 
Storage 
Requirements 
IP should be stored at room temperature (20 - 25°C) in the original packaging. 
Protect from moisture. 
IP stored at site will be maintained under controlled, temperature monitored 
conditions. Excursions between 15-30oC are permitted. Any other excursion from 
the required storage condition will be reported to the Sponsor as soon as practical. 
 
6.1. 
Preparation/Handling/Storage/Accountability 
1. The Investigator or designee must confirm appropriate temperature conditions have been 
maintained during transit for all IP received and any discrepancies are reported and 
resolved before use of the IP. 
2. Only subjects enrolled in the study may receive IP and only authorized site staff may 
supply study medications. All study medication must be stored in a secure, 
environmentally controlled, and monitored (manual or automated) area in accordance 
with the labeled storage conditions with access limited to the Investigator and authorized 
site staff. 
3. The Investigator, institution, or the head of the medical institution (where applicable) is 
responsible for IP accountability, reconciliation, and record maintenance (ie, receipt, 
reconciliation, and final disposition records). 

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6.4.2. 
Restricted Medications 
Restricted medications are defined as medications which should be avoided, if possible; 
however, they are not prohibited during this study if stable for at least one month before 
screening. If such medications are required, consider switching to another medication in the class 
that is not restricted. Please refer to Appendix 9 (Section 10.9) for restricted medications. 
6.4.3. 
Rescue Medicine 
Subjects will be provided with albuterol/salbutamol for use as needed. The rescue medication 
will be locally sourced or reimbursed. Subjects are permitted to use the study-provided 
albuterol/salbutamol or any other short-acting bronchodilator. All rescue medication use is to be 
captured in the eDiary. For the purposes of data capture within the eDiary, one nebule should be 
captured as 4 puffs of rescue medication. 
 If the subject requires medication in addition to a short-acting bronchodilator for treating asthma 
symptoms, the subject should contact the study site for evaluation of their asthma status. 
6.5. 
Dose Modification 
Dose modifications of IP are not permitted. Subjects who are unable to tolerate their assigned 
dose of IP must be discontinued from IP. 
6.6. 
Intervention After the End of the Study 
Subjects who complete the study and meet the eligibility criteria for the Extension Study (ES) 
may be offered the opportunity to receive active treatment in the ES when the study is available. 
7. 
DISCONTINUATION OF INVESTIGATIONAL PRODUCT AND 
SUBJECT WITHDRAWAL FROM THE STUDY 
7.1. 
Discontinuation of Investigational Product 
Permanent discontinuation of IP does not mean withdrawal from the study, and remaining study 
procedures should be completed as indicated by the study protocol. If study IP is permanently 
discontinued, the subject will be encouraged to remain in the study and continue to complete all 
study visits as per the SoA (Section 1.3). If a subject permanently discontinues IP prior to Visit 8 
(Week 20) and remains in the study through Visit 9 (Week 24), the subject will not need to 
return for the Follow-up visit. 
Sections 7.1.1 and 7.1.2 define mandatory criteria for permanent discontinuation of IP. 
For subjects who simultaneously discontinue IP and withdraw from the study, the Early 
Discontinuation of IP visit procedures should be conducted, as shown in the SoA (Section 1.3), 
and a separate Early Withdrawal from Study visit is not needed. The subjects should be 
encouraged to return for the Follow-up visit. 
7.1.1. 
QTc Stopping Criteria 
Subjects must permanently discontinue IP if QTcF > 500 msec.  

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7.1.2. 
Pregnancy 
A subject must permanently discontinue IP if the subject becomes pregnant. See Appendix 4 
Section 10.4 and Section 8.3.4 for additional details. 
The Early Discontinuation of IP visit procedures should be conducted, as shown in the SoA 
(Section 1.3), and a separate Early Withdrawal from Study visit is not needed.  
7.2. 
Subject Withdrawal from the Study 
A subject may withdraw or be withdrawn from the study for the following reasons: 
• Physician decision 
• AE  
• Noncompliance with study drug 
• Withdrawal by subject 
• Study terminated by Sponsor 
• Site terminated by Sponsor 
• Lost to follow-up 
• Lack of efficacy 
• Pregnancy 
The reason for subject withdrawal from the study will be recorded in the eCRF. 
At the time of withdrawal from the study, if possible, an Early Withdrawal from Study visit 
should be conducted, as shown in the SoA (Section 1.3). See SoA for data to be collected at the 
time of study withdrawal and follow-up and for any further evaluations that need to be 
completed. 
For subjects who simultaneously discontinue IP and withdraw from the study, the Early 
Discontinuation of IP visit procedures should be conducted, as shown in the SoA (Section 1.3), 
and a separate Early Withdrawal from Study visit is not needed. The subjects should be 
encouraged to return for the Follow-up visit. 
If a subject withdraws from the study, he/she may request destruction of any samples taken and 
not tested, and the Investigator must document this in the site study records. 
7.3. 
Lost to Follow up 
A subject will be considered lost to follow-up if he or she repeatedly fails to return for scheduled 
visits and is unable to be contacted by the study site. 
The following actions must be taken if a subject fails to return to the clinic for a required study 
visit: 
• The site must attempt to contact the subject and reschedule the missed visit as soon as 
possible and counsel the subject on the importance of maintaining the assigned visit 

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schedule and ascertain whether or not the subject wishes to and/or should continue in 
the study. 
• Before a subject is deemed lost to follow up, the Investigator or designee must make 
every effort to regain contact with the subject (where possible, 3 telephone calls and, 
if necessary, a certified letter to the subject’s last known mailing address or local 
equivalent methods). These contact attempts should be documented in the subject’s 
medical record. 
• The Sponsor may also attempt to ascertain vital status on subjects deemed lost to 
follow up. 
• Should the subject continue to be unreachable, he/she will be considered to have 
withdrawn from the study. 
8. 
STUDY ASSESSMENTS AND PROCEDURES 
• Study procedures and their timing are summarized in the SoA. Protocol waivers or 
exemptions are not allowed. 
• Immediate safety concerns should be discussed with the Sponsor immediately upon 
occurrence or awareness to determine if the subject should continue or discontinue IP. 
• Adherence to the study design requirements, including those specified in the SoA 
(Section 1.3), is essential and required for study conduct. 
• All screening and randomization evaluations must be completed and reviewed to 
confirm that potential subjects meet all eligibility criteria. The Investigator will 
maintain a log to record details of all subjects screened to either confirm eligibility or 
record reasons for screening or Run-in failures, as applicable. 
The suggested order of study procedures should be as follows. (Note: this list is not all inclusive. 
Review the SoA and the Study Reference Manual for additional guidance.) 
Screening Visit (Visit 1): all procedures should be completed on the same day with the exception 
of the Informed Consent, which should be obtained prior to the Visit: 
• Informed consent 
• Demography 
• Concomitant medications and medical history 
• Vital signs 
• Physical exam 
• 12-lead electrocardiogram 
• Fractional exhaled nitric oxide (FeNO) 
• Spirometry pre and post bronchodilator 

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• Have subject complete the ACQ-5 within the eDiary and download the completed 
questionnaire PRIOR to the subject leaving the clinic 
• Review of inclusion/exclusion criteria 
• Collect urine and blood samples 
• Record adverse events, if any 
• Ensure subject has a rescue inhaler 
• Dispense eDiary and train subject in its use 
• Complete eCRF 
Note: During the Run-in period, the site should review the vendor overread of the ECG and 
spirometry report and the laboratory results, including the blood eosinophil count. If the 
overread or laboratory results indicates that the subject is not eligible for randomization, the 
subject should be contacted to return all study provided materials to the site. However, in a 
subject with prior evidence of an eosinophilic phenotype, as assessed by the Investigator, an 
eosinophil count < 250 cells/µL may be repeated during Run-in upon approval by the 
Medical Monitor. 
Randomization Visit (Visit 2): All procedures should be completed on the same day. Sputum 
induction and Exhaled Breath Condensate may be conducted on the next calendar day when 
necessary, followed by the first dose in clinic and post PK sample. Randomization should be 
performed on the day of first dose in clinic. (List is not all inclusive. Review the SoA and the 
Study Reference Manual for additional guidance.) 
• Download the eDiary and check if today’s diary has been completed 
• Review eDiary to assess eligibility 
• Review randomization eligibility criteria 
• Have subject complete questionnaires 
• Exacerbation review 
• Concomitant medications and adverse event review 
• Vital signs 
• FeNO 
• Exhaled breath condensate (EBC) analysis (only at select sites that are properly 
trained and qualified) 
• Spirometry (pre-bronchodilator only) 
• Collect lab samples and predose PK sample 
• Sputum induction (only at select sites that are properly trained and qualified) 
• Register visit in the eCRF 
• Ensure subject has a rescue inhaler  

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• Dispense IP 
• Collect post-dose PK sample at 2.5 hours post-dose 
• Complete eCRF 
Other visits when these procedures are part of the visit: 
• Have the subject complete questionnaires 
• Vital signs 
• ECG 
• FeNO 
• EBC analysis (only at select sites that are properly trained and qualified) 
• Spirometry (pre-bronchodilator only) 
• Collect lab samples and predose pharmacokinetic sample 
• Sputum induction (only at select sites that are properly trained and qualified) 
8.1. 
Efficacy Assessments 
8.1.1. 
Asthma Worsening (Primary Endpoint) 
At each visit, the Investigator or designee will:  
• Download and review the eDiary report for alerts for AM PEF, rescue medication 
use, and asthma symptoms 
• Have the subject complete the ACQ-5 in clinic and review to assess for an increase in 
ACQ-5 score ≥ 0.5 compared to baseline 
• Measure spirometry at each visit except Visit 3 (Week 2), and the FEV1 will be 
assessed to look for a decrease of > 20% from baseline 
• Interview the subject to inquire about recent use of systemic corticosteroids (for 3 or 
more days) for asthma, or an Emergency Department visit or hospitalization for 
asthma.  If the criteria for a severe asthma exacerbation are met, the site staff will 
complete the exacerbation page within the eCRF. Courses of systemic corticosteroids 
separated by 7 or more days will be counted as separate severe exacerbations. 
8.1.2. 
eDiary Asthma Parameters and Alerts 
The subject will be asked to record the following parameters daily in the eDiary from the 
Screening visit through the Follow-up visit: 
• Morning peak flow (best of three efforts) before rescue medication usage (L/min) 
• Puffs of rescue medication used over the previous 24 hours 
• Asthma symptom score over the previous 24-hours using a 6-point scale (Appendix 7 
in Section 10.7) 

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• Frequency of awakening due to asthma symptoms requiring rescue medication use 
The eDiary is programmed to alert the subject about potential asthma worsening. Please refer to 
Section 4.1.1 for alert criteria. 
Subjects will be issued a paper worksheet to record new medical problems and medications taken 
during the study. This will be used to assist subject recall in discussions with the Investigator or 
designee. 
The eDiary information is to be downloaded and reviewed at each visit for potential asthma 
worsening, asthma exacerbations, and to assess compliance with eDiary completion. The subject 
diary data should be archived by site at the end of the study. 
8.1.3. 
Pulmonary Function Testing including Reversibility 
Pre-albuterol/salbutamol morning FEV1 will be measured using electronic spirometry between 
5:00 AM and 12:00 noon and within ± 1 hour from the time of the Screening visit FEV1 
measurement time. Spirometry will be measured at all visits except Visit 3. Subjects should 
withhold short-acting beta-agonist (SABA) use for ≥ 6 hours prior to measurement of 
spirometry, long-acting beta-agonists (LABAs) for ≥ 12 hours prior to spirometry and ultra-
LABA (eg, vilantrol) > 24 hours prior to spirometry. Additionally, forced vital capacity (FVC), 
FEV1/FVC, PEF and forced expiratory flow at 25% to 75% (FEF25-75) will be recorded. For 
predicted values, the Global Lung Initiative will be used. Additional details for pulmonary 
function testing will be available in the Study Reference Manual. 
Reversibility 
At the Screening visit, reversibility in FEV1 will be measured before and within 30 minutes (± 15 
minutes) of albuterol/salbutamol 360/400 µg via metered dose inhaler (MDI) or one nebulized 
treatment of albuterol/salbutamol. The subject must improve by at least 12% in FEV1 to be 
eligible to enter the Run-in period. If the target is not met, historical documentation of 
reversibility in the 24 months prior to Screening visit or historical documentation of airway 
hypersensitivity may be allowed upon review and approval by the Medical Monitor. 
Reversibility in FEV1 will also be assessed at Visit 9 (Week 24) or the Early Discontinuation of 
IP visit. 
8.1.4. 
Asthma Control Questionnaire-5 
The ACQ-5 is a five-item questionnaire which has been developed as a measure of the subject’s 
asthma control that can be quickly and easily completed (Juniper, 2005). The questions are 
designed to be self-completed by the subject. The five questions enquire about the frequency 
and/or severity of symptoms in the prior week (nocturnal awakening, activity limitation, 
shortness of breath, wheeze). The response options for each of these questions consists of a zero 
(no impairment/limitation) to 6 (total impairment/limitation) scale. The minimal clinically 
important difference (MCID) is 0.5 points. 
The subject should be provided with a quiet area in which to complete the questionnaire within 
the eDiary. The Investigator or designee should ask the subject to complete the questions as 
accurately as possible. If the subject requests assistance or clarification for any of the questions, 
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he/she felt over the prior week. The subject should be assured that there are no right or wrong 
answers. The Investigator should not provide the subject with any answer or attempt to interpret 
any portion of a question. 
It is recommended that the ACQ be administered at the same time during each visit. To avoid 
biasing responses, the subject should not be told the results of diagnostic tests prior to 
completing the ACQ and the ACQ should be performed prior to any procedures that might 
influence the subject’s responses. Adequate time should be allowed to complete all items on the 
ACQ. 
8.1.5. 
Asthma Quality of Life Questionnaire- Standardized (AQLQ-S) 
The AQLQ-S is a disease-specific, self-administered quality of life questionnaire developed to 
evaluate the impact of asthma on the subject’s quality of life (Juniper, 1993). The questionnaire 
contains 32 items in 4 domains with a 2-week recall period: activity limitation (11 items), 
symptoms (12 items), emotional function (five items) and environmental stimuli (4 items). 
Additionally, each of the 32 responses are averaged to produce an overall quality of life score. 
Responses are scored on a seven-point scale with a value of 1 indicating total impairment and 
7 indicating no impairment. The minimal clinically important difference (MCID) is 0.5 points 
(Juniper, 1994). 
The AQLQ-S will be completed at the visits specified in the SoA (Section 1.3). The AQLQ-S 
should be completed at approximately the same time during each visit. Subjects should not be 
told the results of any assessments or study procedures before the questionnaire is completed to 
avoid biasing the results. 
Subjects should complete all questions within the AQLQ-S as accurately as possible. If the 
subject requests assistance or clarification for completing the question responses, he/she will be 
asked to reread the question and instructions and encouraged to give the answer that best reflects 
their current feeling. The subject should be reassured that there are no right or wrong answers. 
8.1.6. 
Sino-Nasal Outcome Test 
Sino-Nasal Outcome Test (SNOT-22) is a quality of life instrument to assess the impact of 
chronic rhinosinusitis and utilizes a 2-week recall period (Hopkins, 2009). The questionnaire will 
only be completed by subjects with a prior history of sinusitis, nasal polyps, or allergic rhinitis to 
assess whether GB001 has an impact on this common comorbidity in patients with asthma. 
The questionnaire consists of 22 items across 5 domains: Nasal, Ear, Sleep, General and 
Practical, and emotional. A scale ranging from 0 (no problem) to 5 (problem as bad as it can be) 
is used to respond to each item in the questionnaire with the total global score ranging from 0 to 
110. The global MCID is 8.9. 
8.1.7. 
Hair Assessment 
The DP2 pathway has been implicated as being involved in androgenic alopecia and antagonizing 
this pathway has shown benefit as a potential treatment for alopecia (Garza, 2012; Nieves, 2014). 
Therefore, subjects will be assessed for the presence or absence of scalp hair loss at baseline and 
at conclusion of IP treatment. 

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A visual scale (Norwood classification for male subjects and Savin classification for female 
subjects) to characterize the degree of scalp hair loss at baseline and at the end of the study will 
be used (Gupta, 2016). This information will be complemented with a modified questionnaire to 
assess patient perceptions of scalp hair growth at the end of the study (Appendix 10; 
Section 10.11). This questionnaire includes 2 simple questions to describe possible scalp hair 
growth changes during the study period. 
8.2. 
Safety Assessments 
Planned time points for all safety assessments are provided in the SoA. 
8.2.1. 
Physical Examinations 
• A complete physical examination including but not limited to an evaluation of the 
lungs and cardiovascular systems as well as visualization of nose for polyps will be 
conducted as designated in the SoA (see Section 1.3). The presence or absence of hair 
loss will also be assessed. The results of the physical examination will be recorded in 
the subject’s notes and any significant unfavorable change from the screening exam 
will be recorded as an AE both in the subject’s notes and in the eCRF. 
• Height and weight will also be measured and recorded. 
• The physical exam should be conducted prior to spirometry. 
8.2.2. 
Vital Signs 
• Pulse rate, respiratory rate, temperature and blood pressure will be assessed. 
• Blood pressure and pulse measurements will be assessed with the subject in a sitting 
position with a completely automated device. Manual techniques will be used only if 
an automated device is not available. 
• Blood pressure and pulse measurements should be preceded by at least 5 minutes of 
rest for the subject in a quiet setting without distractions (eg, television, cell phones). 
• Vital signs will be measured after 5 minutes rest and prior to spirometry and ECG 
measurements. 
8.2.3. 
Electrocardiograms 
• Single 12-lead ECG will be obtained as outlined in the SoA (see Section 1.3) using an 
ECG machine that automatically calculates the heart rate and measures PR, QRS, QT, 
and QTc intervals. Refer to Section 7.1.1 for QTc stopping criteria. 
• ECG will be centrally read by the Sponsor’s designee via the electronic portal. 
• Subjects with evidence of a significant abnormality in the 12-lead ECG obtained at 
screening, including prolongation of the QTc interval will not be eligible to 
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8.2.4. 
Clinical Safety Laboratory Assessments 
• See Appendix 2 (Section 10.2) for the list of clinical laboratory tests to be performed 
and to the SoA for the timing and frequency. Details for collection, processing and 
shipping of samples to the central laboratory are provided in a separate Laboratory 
Manual. 
• The Investigator must review the laboratory report, document this review, and record 
any clinically relevant changes occurring during the study in the AE section of the 
eCRF. The laboratory reports must be filed with the source documents. Clinically 
significant abnormal laboratory findings are those which are not associated with the 
underlying disease, unless judged by the Investigator to be more severe than expected 
for the subject's condition. 
• All laboratory tests with values considered clinically significantly abnormal during 
participation in the study should be repeated until the values return to normal or 
baseline or are no longer considered clinically significant by the Investigator or 
Medical Monitor. For additional liver safety monitoring, refer to Appendix 6 
(Section 10.6). 
− If such values do not return to normal/baseline within a period of time judged 
reasonable by the Investigator, the etiology should be identified and the Sponsor 
notified. 
• All protocol-required laboratory assessments, as defined in Appendix 2 (Section 
10.2), must be conducted in accordance with the Laboratory Manual and the SoA. 
• If laboratory values from non-protocol specified laboratory assessments performed at 
the institution’s local laboratory require a change in subject management or are 
considered clinically significant by the Investigator (eg, SAE or AE or dose 
modification), then the results must be recorded in the eCRF. 
8.3. 
Adverse Events, Serious Adverse Events, and Adverse Events of 
Interest 
The definitions of an AE, SAE, and AE of Interest can be found in Appendix 3 (Section 10.3). 
AE will be reported by the subject (or, when appropriate, by a caregiver, surrogate, or the 
subject's legally authorized representative). 
The Investigator and any qualified designees are responsible for detecting, documenting, and 
recording events that meet the definition of an AE, SAE, or AE of Interest. 
8.3.1. 
Time Period and Frequency for Collecting AE and SAE Information 
All AEs/SAEs will be collected from the time of signing the ICF until 4 weeks after the last IP 
dose. For subjects who permanently discontinue IP early but remain in the study, AEs will 
continue to be collected until the completion of Visit 9 (Week 24) or 4 weeks after the last dose 
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Medical occurrences that begin before the start of IP but after obtaining informed consent will be 
recorded on the Medical History/Current Medical Conditions section of the eCRF not the AE 
section. 
All SAEs will be recorded and reported to the Sponsor or designee immediately upon the site 
learning of an event and under no circumstance should this exceed 24 hours, as indicated in 
Appendix 3 (Section 10.3.5). The Investigator will submit any updated SAE data to the Sponsor 
within 24 hours of it being available. 
Investigators are not obligated to actively seek AEs or SAEs that start after conclusion of the 
study participation. However, if the Investigator learns of any SAE, including a death, at any 
time after a subject has been discharged from the study, and he/she considers the event to be 
reasonably related to the IP or study participation, the Investigator must promptly notify the 
Sponsor. 
8.3.2. 
Method of Detecting AEs and SAEs 
The method of recording, evaluating, and assessing causality of AE and SAE and the procedures 
for completing and transmitting SAE reports are provided in Appendix 3 (Section 10.3). 
Care will be taken not to introduce bias when detecting AEs and/or SAEs. Open-ended and 
non-leading verbal questioning of the subject is the preferred method to inquire about 
AE occurrences. 
8.3.3. 
Follow-up of AEs and SAEs 
After the initial AE/SAE report, the Investigator is required to proactively follow each subject at 
subsequent visits/contacts. All SAEs and liver events will be followed until resolution, 
stabilization, the event is otherwise explained, or the subject is lost to follow up (as defined in 
Section 7.3). Further information on follow-up procedures is given in Appendix 3 (Section 10.3). 
Regulatory Reporting Requirements for SAEs 
• Prompt notification by the Investigator to the Sponsor of a SAE is essential so that 
legal obligations and ethical responsibilities towards the safety of subjects and the 
safety of an IP under clinical investigation are met. 
• The Sponsor has a legal responsibility to notify both the local regulatory authority 
and other regulatory agencies about the safety of an IP under clinical investigation. 
The Sponsor will comply with country-specific regulatory requirements relating to 
safety reporting to the regulatory authority, Institutional Review Boards 
(IRB)/Independent Ethics Committees (IEC), and Investigators. 
• Investigator safety reports must be prepared for SUSAR according to local regulatory 
requirements and Sponsor policy and forwarded to Investigators as necessary. 
• An Investigator who receives an Investigator safety report from the Sponsor 
describing a SAE or other specific safety information (eg, summary or listing of 
SAEs) will review and then file it along with the Investigator’s Brochure. The 
Investigator will then notify the IRB/IEC, if appropriate according to local 
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In the event of an overdose, the Investigator should: 
1. Contact the Medical Monitor as soon as possible. 
2. Closely monitor the subject for any AE/SAE and laboratory abnormalities. 
3. Document the quantity of the excess dose as well as the duration of the overdose. 
Decisions regarding dose interruptions or modifications will be made by the Investigator in 
consultation with the Medical Monitor based on the clinical evaluation of the subject. 
8.5. 
Pharmacokinetics 
• Blood samples of approximately 6 mL will be collected for measurement of plasma 
concentrations of GB001 and possibly metabolites of GB001 as specified in the SoA 
(see Section 1.3): 
− At the Randomization visit, the PK samples will be collected predose and 
approximately 2.5 hours postdose. 
− For all other visits where PK samples are collected, the sample will be collected at 
any time during the visit. The subject will be instructed to take their dose in the 
evening at their regular dosing time and to record the time of dosing on a paper 
worksheet. 
• Each plasma sample will be divided into 3 aliquots. 
Drug concentration information that may unblind the study will not be reported to investigative 
sites or blinded personnel until the study has been unblinded. 
8.6. 
Pharmacodynamics and Biomarkers 
Blood, nasal, and urine samples will be collected at the designated times specified in the SoA 
(see Section 1.3) and may be used as the basis for multiple exploratory assays to evaluate the 
effect of GB001 on a range of potential target engagement and PD biomarkers. 
Airway samples (eg, nasosorption, sputum, EBC) may be collected at the designated times 
specified in the SoA at properly trained and qualified sites. These samples may be used for 
multiple exploratory assays to evaluate the effect of GB001 on potential target engagement and 
PD biomarkers. 
Samples may be stored at a facility selected by the Sponsor, to enable further analysis of 
biomarker responses to GB001, for a maximum of 8 years (or according to local regulations) 
following the last subject’s last visit for the study. 
Residual blood, airway and urine samples may be stored for potential future identification of 
factors or profiles that correlate with measures of response to GB001. 
For more details on the procedures, please refer to the study specific Laboratory Manual. 
8.6.1. 
Induced Sputum 
Induced sputum may be collected at selected trained and qualified sites in a subset of subjects 
with baseline ≥ 2%) with a goal of achieving approximately 20 subjects per treatment group and 

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9. 
STATISTICAL CONSIDERATIONS 
9.1. 
Statistical Hypotheses 
This study is designed to demonstrate the superiority of GB001 versus placebo, when added to 
SOC therapy, on the primary endpoint of the proportion of subjects who experience worsening of 
asthma by Week 24. 
9.2. 
Sample Size Determination 
A total sample size of approximately 480 subjects (approximately 120 per treatment group, 
randomized in a 1:1:1:1 ratio) is estimated to provide 80% power to detect a reduction in odds of 
66% between each GB001 group and placebo at an 0.050 two-sided level of significance for the 
primary endpoint of the proportion of subjects who experience worsening of asthma by Week 24. 
This assumes the proportion of subjects who experience worsening of asthma by Week 24 is 
25% in the placebo group and 10.2% in each GB001 group and a dropout rate of 8%. 
Randomization will be stratified by baseline ICS dose (medium or high, as defined in 
Appendix 9; Section 10.9) and country. 
9.3. 
Populations for Analyses 
The following major analysis populations are defined: 
• All enrolled population:  All subjects who consent to study participation. This 
population will be utilized for summaries of subject disposition. 
• Run-in period population:  All enrolled subjects who enter the Run-in period. This 
population will be utilized for summaries of subject disposition. 
• Intent-to-treat (ITT) population:  All subjects who are randomized and receive at least 
1 dose of IP, with subjects grouped according to randomized treatment. 
• Per-protocol (PP) population:  All subjects in the ITT population who do not violate 
terms of the protocol that may affect primary or secondary efficacy outcomes. The 
criteria for the PP population will be determined prior to unblinding and will be 
described in detail in the Statistical Analysis Plan (SAP). 
• Safety population:  All subjects who receive at least 1 dose of IP, with subjects 
grouped according to their actual treatment. 
9.4. 
Statistical Analyses 
In general, continuous variables will be summarized using the number of subjects with non-
missing data, mean, standard deviation, minimum, and maximum. Continuous variable 
summaries will include standard error, where appropriate. Categorical variables will be 
summarized using counts and percentages. Baseline value will be defined as the last non-missing 
value on or before the date of the first dose of IP. This section is a summary of the planned 
statistical analyses of the primary and secondary endpoints. 

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Given that the interim analysis is administrative, will not result in any statistical inferences being 
made, and is not intended to result in any modification to the study (ie, the study will be 
continued and completed regardless of the interim analysis results), no Type I error will be 
allocated to the interim analysis. 
9.5.1. 
Independent Data Monitoring Committee 
An IDMC will regularly monitor overall safety and emerging efficacy results, as well as general 
aspects of study conduct, to ensure that the benefits and risks of study participation remain 
acceptable. Following an initial organizational IDMC meeting, the first IDMC meeting at which 
results are reviewed will occur after approximately 50 subjects have been randomized and have 
completed 12 weeks on study or within 12 months of the first subject randomized. 
Based on these regular reviews of emerging results, the IDMC will recommend to the Sponsor 
continuation, modification, or termination of the study. 
Meeting structure, schedule, and procedures, including communication between the Sponsor and 
the IDMC, the content and format of IDMC reports, and other relevant details, will be 
determined in consultation with IDMC members and detailed in a separate IDMC charter.  

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10. 
APPENDICES 
10.1. 
Appendix 1:  Regulatory, Ethical, and Study Oversight 
Considerations 
10.1.1. 
Regulatory and Ethical Considerations 
• This study will be conducted in accordance with the protocol and with the following: 
− Consensus ethical principles derived from international guidelines including the 
Declaration of Helsinki and Council for International Organizations of Medical 
Sciences (CIOMS) International Ethical Guidelines 
− Applicable ICH Good Clinical Practice (GCP) Guidelines 
− Applicable laws and regulations 
• The protocol, protocol amendments, ICF, Investigator Brochure, eDiary and other 
relevant documents (eg, advertisements) must be submitted to an IRB/IEC by the 
Investigator and reviewed and approved by the IRB/IEC before the study is initiated. 
• Any amendments to the protocol will require IRB/IEC approval before 
implementation of changes made to the study design, except for changes necessary to 
eliminate an immediate hazard to study subjects. 
• The Investigator will be responsible for the following: 
− Providing written summaries of the status of the study to the IRB/IEC annually or 
more frequently in accordance with the requirements, policies, and procedures 
established by the IRB/IEC 
− Notifying the IRB/IEC of SAEs or other significant safety findings as required by 
IRB/IEC procedures 
− Providing oversight of the conduct of the study at the site and adherence to 
requirements of 21 CFR, ICH guidelines, the IRB/IEC, European regulation 
536/2014 for clinical studies (if applicable), and all other applicable local 
regulations 
10.1.2. 
Informed Consent Process 
• The Investigator or his/her representative will explain the nature of the study to the 
subject or his/her legally authorized representative and answer all questions regarding 
the study. 
• Participants must be informed that their participation is voluntary. Participants or 
their legally authorized representative will be required to sign a statement of informed 
consent that meets the requirements of 21 CFR 50, local regulations, ICH guidelines, 
Health Insurance Portability and Accountability Act (HIPAA) requirements, where 
applicable, and the IRB/IEC or study center. 
• The medical record must include a statement that written informed consent was 
obtained before the subject entered the study and the date the written consent was 

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obtained. The authorized person obtaining the informed consent must also sign the 
ICF. 
• Participants must be re-consented to the most current version of the ICF(s) during 
their participation in the study. 
• A copy of the ICF(s) must be provided to the subject or the subject’s legally 
authorized representative. 
• Subjects who are rescreened are required to sign a new ICF. 
• The ICF will contain a separate section that addresses the use of remaining mandatory 
samples for optional exploratory research. The Investigator or authorized designee 
will explain to each subject the objectives of the exploratory research. Subjects will 
be told that they are free to refuse to participate and may withdraw their consent at 
any time and for any reason during the storage period. A separate signature will be 
required to document a subject's agreement to allow any remaining specimens to be 
used for exploratory research. Subjects who decline to participate in this optional 
research will not provide this separate signature. 
• A pharmacogenetics (PGx) consent form must be offered to all subjects and the 
process must be documented, unless prohibited by local regulations. 
10.1.3. 
Data Protection 
• Participants will be assigned a unique identifier by the Sponsor. Any subject records 
or datasets that are transferred to the Sponsor will contain the identifier only; subject 
names or any information which would make the subject identifiable will not be 
transferred. 
• The subject must be informed that his/her personal study-related data will be used by 
the Sponsor in accordance with local data protection law. The level of disclosure must 
also be explained to the subject. 
• The subject must be informed that his/her medical records may be examined by 
Clinical Quality Assurance auditors or other authorized personnel appointed by the 
Sponsor, by appropriate IRB/IEC members, and by inspectors from regulatory 
authorities. 
10.1.4. 
Dissemination of Clinical Study Data 
• A clinical study report will be developed by the Sponsor at completion of data 
analysis. This report will be a clinical and statistical integrated report, according to 
the ICH E3 guidelines. 
• Sponsor will register the study and post study results regardless of outcome on a 
publicly accessible website in accordance with the applicable laws and regulations. 
10.1.5. 
Data Quality Assurance 
• All subject data relating to the study will be recorded on printed or electronic eCRF 
unless transmitted to the Sponsor or designee electronically (eg, laboratory data). The 

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Investigator is responsible for verifying that data entries are accurate and correct by 
physically or electronically signing the eCRF. 
• The Investigator must maintain accurate documentation (source data) that supports 
the information entered in the eCRF. 
• The Investigator must permit study-related monitoring, audits, IRB/IEC review, and 
regulatory agency inspections and provide direct access to source data documents. 
• Monitoring details describing strategy (eg, risk-based initiatives in operations and 
quality such as Risk Management and Mitigation Strategies and Analytical Risk-
Based Monitoring), methods, responsibilities and requirements, including handling of 
noncompliance issues and monitoring techniques (central, remote, or on-site 
monitoring) are provided in the Monitoring Plan. 
• The Sponsor or designee is responsible for the data management of this study 
including quality checking of the data. 
• The Sponsor assumes accountability for actions delegated to other individuals (eg, 
Contract Research Organizations). 
• Study monitors will perform ongoing source data verification to confirm that data 
entered into the eCRF by authorized site personnel are accurate, complete, and 
verifiable from source documents; that the safety and rights of subjects are being 
protected; and that the study is being conducted in accordance with the currently 
approved protocol and any other study agreements, ICH GCP, and all applicable 
regulatory requirements. 
• Records and documents, including signed ICFs, pertaining to the conduct of this 
study must be retained by the Investigator per ICH-GCP and local regulations or 
institutional policies. No records may be destroyed during the retention period 
without the written approval of the Sponsor. No records may be transferred to another 
location or party without written notification to the Sponsor. 
10.1.6. 
Source Documents 
• Source documents provide evidence for the existence of the subject and substantiate 
the integrity of the data collected. Source documents are filed at the Investigator’s 
site. 
• Data entered in the eCRF that are transcribed from source documents must be 
consistent with the source documents or the discrepancies must be explained. The 
Investigator may need to request previous medical records or transfer records, 
depending on the study. Also, current medical records must be available. 
• Source documents are original documents, data, and records from which the subject’s 
eCRF data are obtained. These include but are not limited to hospital records, clinical 
and office charts, laboratory and pharmacy records, diaries, microfiches, radiographs, 
and correspondence. 

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10.1.7. 
Study and Site Closure 
• The Sponsor designee reserves the right to close the study site or terminate the study 
at any time for any reason at the sole discretion of the Sponsor. Study sites will be 
closed upon study completion. A study site is considered closed when all required 
documents and study supplies have been collected and a study-site closure visit has 
been performed. 
• The Investigator may initiate study-site closure at any time, provided there is 
reasonable cause and sufficient notice is given in advance of the intended termination. 
• Reasons for the early closure of a study site by the Sponsor or Investigator may 
include but are not limited to: 
− Failure of the Investigator to comply with the protocol, the requirements of the 
IRB/IEC or local health authorities, the Sponsor's procedures, or GCP guidelines 
− Inadequate recruitment of subjects by the Investigator 
− Discontinuation of further IP development 
10.1.8. 
Publication Policy 
The publication policy is located within the Clinical Study Agreement with the Investigator 
and/or Institution. 

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10.4. 
Appendix 4:  Contraceptive Guidance and Collection of Pregnancy 
Information 
Definitions 
Woman of Childbearing Potential (WOCBP) 
A woman is considered fertile following menarche and until becoming post-menopausal unless 
permanently sterile (see below). 
If fertility is unclear (eg, amenorrhea in adolescents or athletes) and a menstrual cycle cannot be 
confirmed before first dose of IP, additional evaluation should be considered. 
Women in the following categories are not considered WOCBP 
1. Premenarchal 
2. Premenopausal female with 1 of the following: 
• Documented hysterectomy 
• Documented bilateral salpingectomy 
• Documented bilateral oophorectomy 
For individuals with permanent infertility due to an alternate medical cause other than the 
above, (eg, Mullerian agenesis, androgen insensitivity), Investigator discretion should be 
applied to determining study entry. 
Note: Documentation can come from the site personnel’s review of the subject’s medical 
records, medical examination, or medical history interview. 
3. Postmenopausal female 
• A postmenopausal state is defined as no menses for 12 months without an alternative 
medical cause. 
− A high follicle stimulating hormone (FSH) level in the postmenopausal range may 
be used to confirm a postmenopausal state in women not using hormonal 
contraception or hormonal replacement therapy (HRT). However, in the absence 
of 12 months of amenorrhea, confirmation with more than one FSH measurement 
is required. 
• Females on HRT and whose menopausal status is in doubt will be required to use one 
of the non-estrogen hormonal highly effective contraception methods if they wish to 
continue their HRT during the study. Otherwise, they must discontinue HRT to allow 
confirmation of postmenopausal status before study enrollment. 

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Contraception Guidance 
Female Subjects: 
• A female subject is eligible to participate if she is not pregnant or breastfeeding, and 
at least one of the following conditions applies: 
− Is not a woman of childbearing potential (WOCBP) 
OR 
− Is a WOCBP and using a contraceptive method that is highly effective (with a 
failure rate of < 1% per year), preferably with low user dependency (see table 
below), at least 1 month prior to Screening, during the intervention period, and for 
28 days after the last dose of IP, and agrees not to donate eggs (ova, oocytes) for 
the purpose of reproduction during this period. The Investigator should evaluate 
the effectiveness of the contraceptive method in relationship to the first dose of 
IP. 
− A WOCBP must have a negative highly sensitive pregnancy test (urine or serum 
as required by local regulations) within 24 hours before the first dose of IP. 
− If a urine test cannot be confirmed as negative (eg, an ambiguous result), a serum 
pregnancy test is required. In such cases, the subject must be excluded from 
participation if the serum pregnancy result is positive. 
Contraceptive use by men or women should be consistent with local regulations regarding the 
use of contraceptive methods for those participating in clinical studies. 

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Highly Effective Methodsa That Have Low User Dependency  
• 
Implantable progestogen-only hormone contraception associated with inhibition of ovulationb 
• 
Intrauterine device (IUD) 
• 
Intrauterine hormone-releasing system (IUS)b 
• 
Bilateral tubal occlusion 
• 
Vasectomized partner 
 (Vasectomized partner is a highly effective contraceptive method provided that the partner is the sole 
sexual partner of the woman of childbearing potential and the absence of sperm has been confirmed. If not, 
an additional highly effective method of contraception should be used. Spermatogenesis cycle is 
approximately 90 days.) 
Highly Effective Methodsa That Are User Dependent  
• 
Combined (estrogen- and progestogen-containing) hormonal contraception associated with inhibition of 
ovulation 
o 
oral 
o 
intravaginal 
o 
transdermal 
o 
injectable 
• 
Progestogen-only hormone contraception associated with inhibition of ovulationb 
o 
oral 
o 
injectable 
• 
Sexual abstinence 
(Sexual abstinence is considered a highly effective method only if defined as refraining from heterosexual 
intercourse during the entire period of risk associated with the IP. The reliability of sexual abstinence needs to 
be evaluated in relation to the duration of the study and the preferred and usual lifestyle of the subject.) 
a Failure rate of < 1% per year when used consistently and correctly. Typical use failure rates differ from those 
when used consistently and correctly. 
b If locally required, in accordance with Clinical Trial Facilitation Group (CTFG) guidelines, acceptable 
contraceptive methods are limited to those which inhibit ovulation as the primary mode of action. 
Note: Periodic abstinence (calendar, symptothermal, post-ovulation methods), withdrawal (coitus interruptus), 
spermicides only, and lactational amenorrhoea method (LAM) are not acceptable methods of contraception for this 
study. Male condom and female condom should not be used together (due to risk of failure with friction). 

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Collection of Pregnancy Information 
Female Subjects who become pregnant 
• The Investigator will collect pregnancy information on any female subject who 
becomes pregnant while participating in this study. Information will be recorded on 
the appropriate form and submitted to the Sponsor within 24 hours of learning of a 
subject's pregnancy. 
• The subject will be followed to determine the outcome of the pregnancy. The 
Investigator will collect follow-up information on the subject and the neonate and the 
information will be forwarded to the Sponsor. The subject will be followed until birth 
or termination of pregnancy. Any termination of pregnancy will be reported, 
regardless of fetal status (presence or absence of anomalies) or indication for the 
procedure. 
• While pregnancy itself is not considered to be an AE or SAE, any pregnancy 
complication or elective termination of a pregnancy will be reported as an AE or 
SAE. A spontaneous abortion is always considered to be an SAE and will be reported 
as such. Any post-study pregnancy related SAE considered reasonably related to the 
IP by the Investigator will be reported to the Sponsor as described in Section 10.3.5. 
While the Investigator is not obligated to actively seek this information in former 
study subjects, he or she may learn of an SAE through spontaneous reporting. 
• Any female subject who becomes pregnant while participating in the study will 
discontinue IP or be withdrawn from the study. 

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10.5. 
Appendix 5:  Genetics 
Use and Analysis of DNA 
•
Genetic variation may impact a subject’s response to IP, susceptibility to, and severity
and progression of disease. Variable response to IP may be due to genetic
determinants that impact drug absorption, distribution, metabolism, and excretion;
mechanism of action of the drug; disease etiology; and/or molecular subtype of the
disease being treated. Therefore, where local regulations and IRB/IEC allow, a
biosample will be collected for DNA analysis from consenting subjects.
•
Samples may be used for research related to GB001 and/or asthma and related
diseases. They may also be used to develop tests/assays including diagnostic tests
related to GB001 and DP2 inhibitors and atopic disease. Genetic research may consist
of the analysis of prespecified candidate polymorphisms.
•
Samples may be analyzed for variation in candidate genes which dramatically affect
the pharmacokinetics of GB001, the safety, and/or efficacy profile. Often times, a
large variability in the plasma concentration–time profiles of any medicine can be
linked to loss of function mutations in the drug metabolizing enzymes and/or
transporters. For example, substantial efforts have been made in reducing the risk of
drug–drug interactions related to cytochrome P450 enzymes and variability caused by
polymorphic expression of cytochrome P450 enzymes (eg, CYP2D6). The effects of
single nucleotide polymorphisms on the PK of GB001 uncovered in the course of this
study may help guide future clinical studies and regulatory review of GB001.
Additional pharmacogenetic analyses may be conducted if it is hypothesized that
doing so may help resolve issues with the clinical data, eg, safety and/or efficacy
observations during the life of the study.
•
The samples may be analyzed as part of a multi-study assessment of genetic factors
involved in the response to GB001 of this class to understand study disease or related
atopic conditions.
•
The results of genetic analyses may be reported in the CSR or in a separate study
summary.
•
The Sponsor will store the DNA samples in a secure storage space with adequate
measures to protect confidentiality.
•
The samples will be retained while research on GB001 continues but no longer than
8 years or other period as per local requirements.
The following genetic parameters may be evaluated in this study: 
•
Genetics (DNA):
SNPs in a) drug metabolizing and enzymes, b) DP2 pathway genes, c) asthma &
atopic pathway genes, e.g. vitamin D

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10.6. 
Appendix 6:  Liver Safety - Actions and Follow-up Assessments 
Liver chemistry will be evaluated as specified in the SoA (Section 1.3) and Appendix 2 
(Section 10.2). Parameters will include ALT, AST, GGT, bilirubin, total bile acids, and ALP.  
For subjects with ALT or AST > 1 × ULN and < 3 × ULN or total bilirubin or direct bilirubin 
> 1 × ULN and ≤ 1.5 × ULN, confirm the value within 24 to 48 hours. Contact the Medical 
Monitor to determine the appropriate liver monitoring schedule (eg, weekly or twice a week). 
The criteria requiring additional liver monitoring with possible interruption of study intervention 
are detailed in Table 4. 
Table 4: 
Liver Chemistry Criteria Requiring Additional Monitoring with Possible 
Interruption of Investigational Product 
Criterion 
Actions 
ALT or AST ≥ 3 × ULN and < 5 × ULN 
or total bilirubin or direct bilirubin > 1.5 
× ULN without symptoms believed to be 
related to liver injury or hypersensitivity, 
and who can be monitored weekly for 4 
weeks 
• 
Notify the Medical Monitor within 24 hours of 
learning of the abnormality to discuss subject safety.  
“Additional Liver Panel” in Table 5 may be requested 
by the Medical Monitor 
• 
Confirm values within 24 to 48 hours via repeat labs. 
If unable to obtain repeat labs within 48 hours, 
discontinue IP. 
• 
Decision to continue or interrupt study intervention 
will be determined by the Investigator and the Medical 
Monitor 
• 
Subject must return weekly or more frequently for 
repeat liver chemistry tests (ALT, AST, GGT, ALP, 
total bile acids, and bilirubin) until the abnormalities 
resolve, stabilize or return to baseline. 
• 
If at any time the subject meets liver chemistry 
interruption criteria (as specified in Table 5), then 
follow the instructions in “Actions and Follow-up 
Assessments” in Table 5 and in consultation with the 
Medical Monitor initiate relevant assessment 
procedures 
 
In the case of AEs of interest (Section 10.3.3), potential re-challenge will be restricted to 
potential DILI cases that have been assessed as unlikely or not related to IP by the HAC and after 
liver enzymes have returned to baseline levels. When re-challenging with IP, obtain repeat liver 
chemistries twice weekly in the first 2 weeks and then weekly for 6 weeks after the re-challenge. 
If there is a rise in liver enzymes > 2 × ULN, then IP should be discontinued permanently.The 
criteria requiring interruption of IP with additional liver monitoring is detailed in Table 5. 

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Table 5: 
Liver Chemistry Criteria Requiring Investigational Product Interruption 
and Additional Monitoring 
 
 
Liver Chemistry – IP Interruption Criteria 
ALT/AST (single occurrence) 
ALT or AST ≥ 5x ULN 
ALT/AST 
ALT or AST ≥ 3x ULN persists for ≥ 4 weeks 
+ Bilirubin a,b 
ALT or AST ≥ 3x ULN and bilirubin > 2x ULN (> 35% direct bilirubin) 
+ INR b 
ALT or AST ≥ 3x ULN and international normalized ratio (INR) > 1.5, if 
INR measured 
+ Cannot Monitor 
ALT or AST ≥ 3x ULN and cannot be monitored weekly for 4 weeks 
+ Symptomatic c 
ALT or AST ≥ 3x ULN associated with symptoms (new or worsening) 
believed to be related to liver injury or hypersensitivity 
Actions and Follow-up Assessments  
Actions 
Follow-Up Assessments 
• 
Immediately discontinue IP 
• 
Report the event to the Medical Monitor 
within 24 hours 
• 
Complete the liver event eCRF and complete 
an SAE data collection tool if the event also 
met the criteria for an SAEb 
• 
Perform liver chemistry follow-up 
assessments 
• 
Monitor the subject until liver chemistry test 
abnormalities resolve, stabilize, or return to 
baseline (see MONITORING) 
• 
Do not restart/rechallenge subject with IP 
unless Medical Monitor approval is granted 
• 
If restart/rechallenge not granted, 
permanently discontinue IP and continue 
subject in the study for any protocol specified 
follow up assessments 
 
MONITORING: 
 
• 
Repeat liver chemistry tests (include ALT, 
AST, GGT, alkaline phosphatase, total bile 
acids, bilirubin, and INR) and perform liver 
event follow-up assessments within 24 hours 
• 
Monitor subject twice weekly until liver 
chemistry test abnormalities resolve, stabilize, 
or return to baseline 
• 
A specialist or hepatology consultation is 
recommended 
 
Additional Liver Panel 
• 
Viral hepatitis serology d 
• 
Obtain INR and recheck with each liver chemistry 
assessment until the ALT and/or AST values show 
downward trend 
• 
Obtain blood sample for pharmacokinetic (PK) 
analysis  
• 
Serum creatine phosphokinase (CPK) and lactate 
dehydrogenase (LDH) 
• 
Fractionate bilirubin, if total bilirubin > 2x ULN 
• 
Obtain complete blood count with differential to assess 
eosinophilia 
• 
Record the appearance or worsening of clinical 
symptoms of liver injury, or hypersensitivity, on the 
adverse event (AE) report form 
• 
Record use of concomitant medications (including 
acetaminophen, herbal remedies, and other over-the-
counter medications) on the concomitant medications 
eCRF 
• 
Record alcohol use on the liver event alcohol intake 
eCRF 
• 
Anti-nuclear antibody, anti-smooth muscle antibody, 
Type 1 anti-liver kidney microsomal antibodies, and 
quantitative total immunoglobulin G (IgG) or gamma 
globulins 
• 
Serum acetaminophen assay 
• 
Liver imaging (ultrasound, magnetic resonance, or 
computerized tomography) and/or liver biopsy to 
evaluate liver disease 
a Serum bilirubin fractionation should be performed if testing is available. If serum bilirubin fractionation is not 
immediately available, discontinue IP if ALT or AST ≥ 3x ULN and bilirubin > 2x ULN. Additionally, if serum 

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bilirubin fractionation testing is unavailable, record the absence/presence of detectable urinary bilirubin on 
dipstick which is indicative of direct bilirubin elevations suggesting liver injury. 
b All events of ALT or AST  ≥ 3x ULN and bilirubin > 2x ULN (> 35% direct bilirubin) or ALT or AST ≥ 3x ULN 
and INR > 1.5 may indicate severe liver injury (possible ‘Hy’s Law’) and must be reported as an SAE 
(excluding studies of hepatic impairment or cirrhosis). The INR stated threshold value will not apply to subjects 
receiving anticoagulants. INR is not part of routine laboratory assessments in this study. 
c New or worsening symptoms believed to be related to liver injury (such as fatigue, nausea, vomiting, right upper 
quadrant pain or tenderness, or jaundice) or hypersensitivity (such as fever, rash or eosinophilia). 
d Includes: expanded viral hepatitis serology (Table 3). 
 

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10.7. 
Appendix 7:  Daily Asthma Symptom Score 
Each morning subjects will record in the eDiary an assessment of the severity of their asthma 
symptoms during the prior 24 hours using the following scale: 
• 0 = No symptoms 
• 1 = Symptoms for one short period 
• 2 = Symptoms for two or more short periods 
• 3 = Symptoms for most of the prior 24 hours which did not affect my ability to carry 
out my daily activities 
• 4 = Symptoms for most of the prior 24 hours which did affect my ability to carry out 
my daily activities 
• 5 = Symptoms so severe that I could not go to work/school or complete my normal 
daily activities 

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10.11. 
Appendix 11:  Assessment of Hair Loss 
Questionnaire to Assess Patient Perceptions of Hair Growth 
1. Do you lose hair to the point that this is concerning?  
 Yes   
 No 
2. Do you have any bald spots?  
 Yes   
 No 
Note: If the subject answered “Yes” to any of the questions above, the site will complete the 
graphical visual assessment for male and female subjects (Norwood and Savin Scales), 
respectively. 
In those subjects who completed the above information, at the end of the study (Last IP Visit) 
the following questions should be completed, please check only one box: 
a. Since initiation of the study, I noticed my bald spot is getting smaller: 
Strongly agree 
 
Agree 
 
A little better 
 
The same 
 
A little worse 
 
Somewhat worse 
 
A lot worse 
 
 
b. Overall, since initiation of the study, I noticed that the growth of my hair is: 
Greatly increased 
 
Moderately increased 
 
Slightly increased 
 
The same 
 
Slightly decreased 
 
Moderately decreased 
 
Greatly decreased 
 

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10.12. 
Appendix 12:  Guidance to Address a Pandemic or Other Global 
Health Emergencies and Potential Impact on the Clinical Study 
In the occurrence of a global health pandemic affecting the conduct of the ongoing study, such as 
the COVID-19 pandemic, study conduct may be adjusted due to subjects being in self-
isolation/quarantine, limited access to public places (including hospitals) due to the risk of 
spreading infections, and health care professionals being committed to critical tasks (FDA, 2020; 
EMA, 2020; Health Canada, 2020; MHRA, 2020). 
Adjustments to the GB001-2001 protocol may be made as described below, in line with global 
regulatory authorities guidance in order to ensure the safety of study participants, maintain 
compliance with GCP, and minimize the risks to trial integrity during the COVID-19 pandemic 
(FDA, 2020; EMA, 2020; Health Canada, 2020; MHRA, 2020). Member states within the 
National Competent Authorities may issue their own guidance requiring country specific 
recommendations to be followed. 
• In the case of missed visits due to COVID-19 (or other health pandemic) related 
reasons: 
− The site should make every effort to contact the subject to confirm and document 
the reason for the missed visit, and at minimum evaluate AEs/SAEs, concomitant 
medications, and asthma exacerbations in order to assess subject status.  
− The subject should continue to collect the daily AM PEF and eDiary responses on 
the eDiary. The eDiary will provide an alert to potential asthma worsening, as 
described in Section 4.1.1. In the event of an alert, the subject should contact the 
site staff as soon as practical to assess the subject’s asthma status. 
• Alternative methods of collecting study assessments may be considered where 
possible: 
− Questionnaires, including ACQ-5, AQLQ, and SNOT-22, may be self-
administered by the subject at home. 
− In certain situations, with Sponsor approval, a local laboratory may be used. 
• Alternative methods of supplying IP to study subjects (eg, direct-to-patient shipment 
from site) may be considered where possible. 
− With prior sponsor approval, IP may be supplied via alternative methods provided 
that laboratory assessments are able to be performed prior to the delivery of IP. In 
all cases, study subjects must provide consent for alternative delivery methods. 
Documentation of consent will be captured in the subject’s study records.  

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10.13. 
Appendix 13:  Abbreviations 
Abbreviation Term 
Description 
ACQ 
Asthma Control Questionnaire 
AE 
adverse event  
ALT 
alanine aminotransferase 
AM 
morning  
ANCOVA 
analysis of covariance 
AQLQ-S 
Asthma Quality of Life Control Questionnaire (standardized) 
AST 
aspartate aminotransferase 
BMI 
body mass index  
BUN 
blood urea nitrogen  
CI 
confidence interval 
CIOMS 
Council for International Organizations of Medical Sciences  
CONSORT 
Consolidated Standards of Reporting Trials 
CPK 
serum creatine phosphokinase  
CRTh2 
chemoattractant receptor-homologous molecule expressed on Th2 
CSR 
clinical study report  
CTFG 
Clinical Trial Facilitation Group  
DILI 
drug induced liver injury 
DP2 
prostaglandin D2 receptor 
DPI 
dry powder inhaler 
EBC 
exhaled breath condensate  
EC 
Ethics Committee 
ECG 
electrocardiogram  
eCRF 
electronic case report form 
EDC 
electronic data capture 
eDiary 
electronic diary 
ES 
extension study 
EW 
early withdrawal 
FEF25-75 
forced expiratory flow at 25% to 75% 
FeNO 
fractional exhaled nitric oxide 
FEV1 
forced expiratory volume in 1 second 
FSH 
follicle-stimulating hormone  

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Abbreviation Term 
Description 
FVC 
forced vital capacity 
GCP 
Good Clinical Practice  
GGT 
gamma-glutamyl transferase  
GINA 
Global Initiative for Asthma 
HAC 
Hepatology Assessment Committee 
HBcAb 
Hepatitis B core antibody  
HBsAg 
Hepatitis B surface antigen 
hCG 
human chorionic gonadotropin  
HIV 
human immunodeficiency virus 
HIPAA 
Health Insurance Portability and Accountability Act  
HPLC 
high performance liquid chromatography  
HRT 
hormonal replacement therapy  
IB 
Investigator’s brochure  
ICF 
Informed Consent Form 
ICH 
International Council for Harmonisation  
ICS 
inhaled corticosteroid 
IDMC 
Independent Data Monitoring Committee  
IEC 
Independent Ethics Committee 
IgG 
immunoglobulin G  
IgM 
immunoglobulin M  
INR 
international normalized ratio  
IP 
investigational product 
IRB 
Institutional Review Board 
IRT 
Interactive Response Technology 
ITT 
intent-to-treat 
IUD 
intrauterine device 
IUS 
hormone-releasing system  
LABA 
long-acting beta agonist 
LAM 
lactational amenorrhoea method  
LAMA 
long-acting muscarinic antagonist 
LDH 
lactate dehydrogenase  
LTRA 
leukotriene receptor antagonist 

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Abbreviation Term 
Description 
MCID 
minimal clinically important difference  
MDI 
metered dose inhaler 
OR 
odds ratio 
PD 
pharmacodynamic  
PEF 
peak expiratory flow 
PGD2 
prostaglandin D2 
PK 
pharmacokinetic 
PP 
Per-protocol 
PRO 
patient reported outcomes 
QTcF 
Fridericia's correction formula for QT interval (interval between Q wave 
and T wave) 
RBC 
red blood cell  
RNA 
ribonucleic acid  
SABA 
short-acting beta-agonist 
SAE 
serious adverse event  
SAP 
Statistical Analysis Plan 
SNOT-22 
Sino-Nasal Outcome Test 
SNP 
single nucleotide polymorphism 
SoA 
schedule of activities  
SOC 
standard of care  
SUSAR 
suspected unexpected serious adverse reaction 
TEAE 
treatment-emergent adverse event 
Th2 
T Helper cell type 2 
ULN 
upper limit of normal  
VOC 
volatile organic compounds  
WBC 
white blood cell  
WOCBP 
women of childbearing potential 

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10.14. 
Appendix 14: Protocol Amendment History 
The Protocol Amendment Summary of Changes Table for the current amendment is located 
directly before the Table of Contents (TOC). 
DOCUMENT HISTORY  
Document  
Date  
Amendment 3 (v4.0) 
18-Feb-2020 
Amendment 2 (v3.0) 
28-Aug-2019 
Amendment 1 (v2.0.0)  
28-Feb-2019  
Original Protocol (v1.0.0)  
02-Aug-2018  
Amendment 3 (v4.0; 18 Feb 2020)  
This amendment is considered to be substantial based on the criteria set forth in Article 10(a) of 
Directive 2001/20/EC of the European Parliament and the Council of the European Union.  
Overall Rationale for the Amendment:  
The purpose of this amendment is to enhance monitoring of liver parameters during the conduct 
of the trial. 
Section # and Name  
Description of Change  
Brief Rationale  
Section 1.3 Schedule of Activities; 
Section 1.2 Schema  
Addition of a Week 1 visit 
(Visit 2.5) serum 
chemistry panel (liver) 
following Randomization 
(Visit 2) 
Week 1 visit was added to 
enhance laboratory 
monitoring during the first 
month following IP 
initiation 
Section 6.2.5 Unblinded Sponsor Medical 
Monitor  
Added new monitoring 
guidelines 
To enable unblinded 
medical monitoring of 
liver and other laboratory 
parameters of interest by a 
designated Sponsor 
Medical Monitor in order 
to protect subject safety 
Section 10.3.3 Adverse Events of Interest 
Updated language 
describing adverse events 
of interest 
Clarified definition of 
adverse events of interest 
Section 10.6 Appendix 6: Liver Safety - 
Actions and Follow-up Assessments 
Modified: 
• 
Discussion of possible 
Investigational 
Product (IP) 
continuation or 
discontinuation if 
ALT or AST ≥ 3 × 
ULN or total bilirubin 
To enhance monitoring of 
liver parameters during 
the conduct of the trial 

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Section # and Name  
Description of Change  
Brief Rationale  
or direct bilirubin > 
1.5 × ULN and 
potential triggering of 
appropriate follow-up 
to include Liver 
Safety Laboratory 
assessments 
• 
ALT or AST > 1 × 
ULN and < 3 × ULN 
or total bilirubin or 
direct bilirubin > 1 × 
ULN and ≤ 1.5 × 
ULN, confirm the 
value within 24 to 48 
hours 
 
Global Change 
Minor revisions to text. 
Administrative 
clarifications were 
incorporated, and 
typographical errors were 
corrected. 
 
Amendment 2 (v3.0; 28 Aug 2019)  
This amendment is considered to be substantial based on the criteria set forth in Article 10(a) of 
Directive 2001/20/EC of the European Parliament and the Council of the European Union based 
on the criteria set forth in Article 10(a) of Directive 2001/20/EC of the European Parliament and 
the Council of the European Union.  
Overall Rationale for the Amendment:  
The purpose of this amendment is to enhance monitoring of liver parameters during the conduct 
of the trial and to provide guidance on drugs that may be associated with hepatoxicity, to provide 
clarification on eligibility criteria, and to evaluate annualized rate of severe asthma exacerbations 
as a secondary (rather than exploratory) endpoint. 
Section # and Name  
Description of Change  
Brief Rationale  
Section 1.1 Synopsis; 
Section 3 Objectives and Endpoints; 
Section 9.4.1.2 Secondary Efficacy Analysis 
Updated annualized rate 
of severe asthma 
exacerbations from 
tertiary/exploratory to 
secondary endpoint. 
Given the clinical 
importance of the 
assessment of severe 
asthma exacerbation, this 
has been elevated to a 
secondary endpoint. 
Section 1.3 Schedule of Activities  
• 
Notes on total bile 
acid, international 
normalized ratio 
• 
Addition of INR 
measurement at 
baseline. Collection of 

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Section # and Name  
Description of Change  
Brief Rationale  
(INR), and 
fractionation of ALP 
if ALP > 1xULN 
were added.  
• 
Added assessment of 
clinical chemistry at 
Week 3. 
a total bile acid   
sample at every visit, 
and fractionation of 
ALP if ALP > 
1xULN. 
• 
Week 3 visit was 
added to enhance 
laboratory monitoring 
during the first month 
following IP 
initiation. 
 
Section 2.2 Background 
 
Added recent results from 
post-hoc analyses. 
 
Updated with results 
which suggest that GB001 
favorably influences lung 
function in subjects with 
Type 2 markers of 
inflammation. 
Section 2.3.1 GB001 Risk/Benefit 
Assessment 
Revised data for GB001. 
Clarified risk/benefit 
profile. 
Section 5.1 Inclusion Criterion #8 
Criterion for airway 
hyperresponsiveness was 
updated. 
Extended period of 
reversibility and added 
historical demonstration 
of airway 
hyperresponsiveness. 
Section 5.2 Exclusion Criteria #4  
 
Added known history of 
non-alcoholic fatty liver 
disease (NAFLD) or 
Gilbert’s Syndrome. 
Clarified liver-related pre-
existing conditions. 
Section 5.3 Randomization Criteria #8  
Added absolute eosinophil 
count and white blood cell 
(WBC) count criteria. 
Enhance safety 
characterization of the 
study population with 
eosinophilic asthma. 
Section 6.4.2 Restricted Medications; 
Section 10.9 Appendix 9: Restricted 
Medications and Treatments 
 
 
Added to the list of 
restricted medications 
those that are known to 
have potential for liver 
toxicity.  
Increased awareness of 
medications which may 
impact liver effects. 
Section 9.4.1.2 Secondary Efficacy Analysis 
Added statistical analysis 
methodology for 
annualized rate of severe 
asthma exacerbation. 
Included statistical 
analysis methodology 
given this has been 
elevated to a secondary 
endpoint. 

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Section # and Name  
Description of Change  
Brief Rationale  
Section 10.2 Appendix 2: Clinical 
Laboratory Tests Table 2 
Total bile acid, INR, and 
fractionation of ALP if 
ALP > 1xULN were 
added. Clarified 
urinalysis. 
To enhance monitoring of 
liver parameters during 
the conduct of the trial. 
Global Change 
Minor revisions to text. 
Administrative 
clarifications were 
incorporated, and 
typographical errors were 
corrected. 
 
Amendment 1 (v2.0.0; 28 Feb 2019)  
This amendment is considered to be substantial based on the criteria set forth in Article 10(a) of 
Directive 2001/20/EC of the European Parliament and the Council of the European Union based 
on the criteria set forth in Article 10(a) of Directive 2001/20/EC of the European Parliament and 
the Council of the European Union.  
Overall Rationale for the Amendment:  
The purpose of this amendment is to provide clarification on Inclusion/Exclusion criteria, 
incorporate new information based on the GB001-1901 study, and to make administrative 
protocol clarifications. 
Section # and Name  
Description of Change  
Brief Rationale  
Section 1.3 Schedule of Activities; 
Section 4.1.1 Study Design   
Written informed consent 
text was updated. 
The modification was 
made to clarify that 
informed consent may be 
obtained prior to Visit 1 to 
allow for medication 
washouts and obtaining 
historical medical records 
when necessary.  
Section 1.3 Schedule of Activities  
Hepatitis B surface 
antigen and Hepatitis C 
antibody text was 
updated. 
Clarification to include 
indeterminate test result. 
 
At-home RNA 
Transcriptome Research 
text was updated. 
Test removed from Early 
Discontinuation visit due 
to logistics. 
 
Nasal sample collection 
was separately listed. 
Clarification to avoid 
confusion so that all 
subjects provide sample. 
 
Notes on sputum 
eosinophil and neutrophil 
Clarification on timing of 
sputum and exhaled 

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Section # and Name  
Description of Change  
Brief Rationale  
and exhaled breath 
condensate assessments at 
Randomization visit were 
added. 
breath condensate analysis 
and first dose. 
Section 3 Objectives and Endpoints 
The text on 
pharmacokinetic (PK) 
analysis was updated. 
Exploratory endpoint was 
added. 
The minor update 
clarified that PK samples 
would be collected from 
plasma. 
Exacerbations was added 
as exploratory endpoint. 
Section 4.2.2 Placebo Rationale 
Text added on timing of 
IDMC meeting. 
Clarification of timing of 
IDMC meeting. 
Section 5.1 Inclusion Criteria #3; 
Section 8.3.4 Pregnancy; 
Section 10.4 Appendix 4:  Contraceptive 
Guidance and Collection of Pregnancy 
Information 
Criterion for male 
contraception was 
removed. 
Data on pregnancies of 
male partners of female 
subjects will no longer be 
collected.  
Contraceptive guidance 
for male subjects was 
removed. Collection of 
information from male 
subjects with partners 
who become pregnant has 
been removed. 
Per CTFG Guidance 
Section 2.3, no male 
contraception is required. 
Section 5.1 Inclusion Criteria #6 
Criteria for ICS plus 
additional controller was 
updated. 
Clarification on length of 
prior treatment with 
medium or high dose ICS 
and clarification of the use 
of additional controller 
medication. 
Section 5.1 Inclusion Criteria #7; 
Section 5.3 Randomization Criteria 
The lower limit for FEV1 
criterion was removed. 
Studies in subjects with 
severe asthma have been 
conducted without lower 
limit of FEV1. Exclusion 
of subjects with low 
FEV1 will be based on 
PI’s assessment. 
Section 5.1 Inclusion Criteria #8 
Text on reversibility was 
revised. 
Clarification on use of 
equivalent dose of 
nebulized bronchodilator. 
Section 5.2 Exclusion Criteria #1 
Text was added to exclude 
smoking of any substance. 
This clarification was 
made to include 
marijuana, its 

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Section # and Name  
Description of Change  
Brief Rationale  
components, and any 
other substances which 
may be smoked. 
Section 5.2 Exclusion Criteria #7 
Text around ECG 
assessment was updated. 
This modification was 
made to clarify that ECG 
assessment could be 
repeated. 
Section 5.2 Exclusion Criteria #18 
Text added to clarify 
criterion. 
Clarification on reasons 
for excluding subjects 
who may participate in 
another study. 
Section 5.4 Screen or Run-In Failures 
Text added to clarify 
designation of Run-in 
failure. 
Clarification on Run-in 
failure definition for this 
study. 
Section 6.2.4 Unblinding of an Individual 
Subject 
Text added to clarify 
conditions for unblinding. 
Clarification of 
procedures to protect 
samples and data for 
unblinding. 
Section 6.4.2 Rescue Medicine 
Text was updated to 
provide additional details. 
This modification was 
made to clarify use of 
rescue medication and 
data capture. 
Section 7.1.2 Pregnancy 
Removed text on Follow-
up visit. 
Clarification on 
procedures if the subject 
who becomes pregnant. 
Section 7.2 Subject Withdrawal from the 
Study 
Updated text to provide 
further clarity. 
Clarification on reasons 
for subject withdrawal 
from study. 
Section 8 Study Assessments and Procedures 
Text was added to 
description of Screening 
and Randomization visits. 
Clarification on timing of 
procedures. 
Section 8.1.1 Asthma Worsening 
Text was added to clarify 
the timing/duration of 
exacerbations. 
Clarification of the 
interval between two 
exacerbations. 
Section 8.6.3 RNA Transcriptome Research 
Text was updated. 
Clarification that not all 
samples may be analyzed. 
Section 8.6.5 Blood Biomarker Analyses 
Text was updated. 
Simplification and 
clarification of possible 
analyses. 
Section 9.3 Populations for Analyses 
Text added for clarity. 
Clarification of 
populations for analyses. 

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Section # and Name  
Description of Change  
Brief Rationale  
Section 9.4 Statistical Analyses 
Text added for clarity. 
Clarification on 
summaries of variables. 
Section 9.4.1 Efficacy Analyses 
Subheading was added on 
efficacy analyses. 
Clarification of the 
population for efficacy 
analyses. 
Section 10.1.2 Informed Consent Process 
Text was added to 
describe 
pharmacogenetics consent 
form. 
Clarification of the 
process for collecting PGx 
informed consent. 
Section 10.2 Appendix 2: Clinical 
Laboratory Tests Table 3;  
Section 10.6 Appendix 6 Table 5  
Specific acetaminophen 
assay was removed. 
Type of acetaminophen 
assay is no longer 
specified to allow 
flexibility in assay 
performed.  
Section 10.3.5 Reporting of SAEs 
Contact information and 
paper submission of SAE 
report was updated. 
Update and clarification 
of contact information and 
on paper submission of 
SAE report. 
Section 10.6 Appendix 6: Liver Safety - 
Actions and Follow-up Assessments 
“Not required in China” 
was removed. 
Updated. 
Section 10.8 Appendix 8: Prohibited 
Medications and Treatments 
Table was updated. 
New data indicated that 
GB001 is not expected to 
have clinically significant 
drug-drug interactions 
with substrates of 
CYP2C8, CYP2C9, 
OATP1B1/1B3, and Pg-p. 
These data supported 
change in prohibited 
medications and 
treatments. 
Section 10.9 Appendix 9: Estimated Clinical 
Comparability of Medium and High Doses 
of Inhaled Corticosteroids 
Table was updated. 
Update due to availability 
of new products. 
Global Change 
Minor revisions to text. 
Typographical errors were 
corrected. 

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11. 
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