Mepolizumab for the Treatment of Chronic Cough With Eosinophilic Airways Diseases
Phase: PHASE4
Conditions: Chronic Cough, Eosinophilic Bronchitis, Asthma
Sponsor: McMaster University

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
 
 
 
 
Clinical Trial Protocol 
 
 
Protocol Title:  
Mepolizumab for the Treatment of Chronic Cough with 
Eosinophilic Airways Disease. 
 
 
Locally Responsible 
Investigator and  
Principle Investigator:  
Dr. Imran Satia MD, PhD 
 
 
 
 
Department of Medicine, McMaster University 
 
 
 
 
1200 Main St. West, HSC 3U9  
 
 
 
 
Hamilton, Ontario, L8N 3Z5 
 
 
 
 
Email: satiai@mcmaster.ca 
 
 
 
 
 
Dr. Paul O’Byrne MD 
 
 
 
 
Department of Medicine, McMaster University 
 
 
 
 
Email: obyrnep@mcmaster.ca 
 
Co-Investigators: 
 
Dr. Gail Gauvreau PhD, Dept Medicine, McMaster University 
 
 
 
 
Dr. Roma Sehmi PhD, Dept Medicine, McMaster University 
 
 
 
 
Dr. Kieran Killian MD, Dept Medicine, McMaster University 
 
 
 
 
Dr. Jacky Smith MD, PhD, University of Manchester, UK 
 
Funding Organization: 
GlaxoSmithKline Inc.  
 
Sponsor:  
 
 
McMaster University 
 
 
 
 
1200 Main St. West, 
 
 
 
 
Hamilton, Ontario 
 
Protocol Number: 
 
ISS-21-4463 
NCT Number:  
 
NCT04765722 
Protocol Version: 
 
2.4 22 June 2023 
 
Short Title: 
 
 
MUCOSA 
 
 
 
 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
2
The study will be performed in accordance with the ethical principles of the Declaration of 
Helsinki, and consistent with International Conference on Harmonization (ICH)/Good Clinical 
Practice (GCP) and applicable regulatory requirements. Approval will be obtained from the local 
ethics committee, and all patients provided written and informed consent. 
 
Principal Investigator 
Imran Satia, MD, Ph.D. 
Assistant Professor 
McMaster University 
Signature 
Jun 16, 2021. 
Date (DD-Mon-YYYY) 
Medical Expert/Qualified Investigator 
Imran Satia, MD, Ph.D. 
Assistant Professor 
McMaster University 
Signature 
Jun 16, 2021. 
Date (DD-Mon-YYYY) 
Medical Monitor/Study Physician 
Imran Satia, MD, Ph.D. 
Assistant Professor 
McMaster University 
Signature 
Jun 16, 2021. 
Date (DD-Mon-YYYY) 
 
 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
3
 
MEDICAL EXPERTS 
 
Study Sponsor Medical  
Dr. Paul O’Byrne, MD,  
Expert  
 
 
Department of Medicine, McMaster University 
 
 
 
 
1200 Main St West, HSC 2E1,  
Hamilton, ON, L8N 3Z5 
Phone: 905-521-2100 x22100 
Email: obyrnep@mcmaster.ca 
 
 
 
 
 
 
Study Physician:  
 
Dr. Imran Satia MD, PhD 
 
 
 
 
Department of Medicine, McMaster University 
 
 
 
 
1200 Main St. West, HSC 3U9  
 
 
 
 
Hamilton, Ontario, L8N 3Z5 
 
 
 
 
Phone: 905-521-2100 x76228 
 
 
 
 
Email: satiai@mcmaster.ca 
 
Clinical Laboratories 
 
 
 
 
Hamilton Regional Laboratory Medicine Program 
50 Charlton Ave E, Hamilton, ON L8N 4A6 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
4
 
Table of Contents 
List of Tables ............................................................................................................................ 7 
List of Figures ........................................................................................................................... 7 
List of Abbreviations ............................................................................................................... 7 
1. 
Introduction .................................................................................................................. 8 
1.1. 
Study Summary ............................................................................................................ 8 
1.2 
Background and Rationale .......................................................................................... 8 
2. 
Hypothesis ................................................................................................................... 11 
3. 
Study Aim ................................................................................................................... 12 
4. 
Study Objectives ......................................................................................................... 12 
5. 
Study Design ............................................................................................................... 12 
5.1. 
Design .......................................................................................................................... 12 
5.2. 
Duration of Study ....................................................................................................... 13 
5.3. 
Number of Sites .......................................................................................................... 13 
5.4. 
Study Period ............................................................................................................... 13 
5.5. 
Study Population ........................................................................................................ 13 
5.6. 
Inclusion Criteria ....................................................................................................... 14 
5.7. 
Exclusion Criteria ...................................................................................................... 14 
5.8. 
Recruitment Process .................................................................................................. 17 
5.9. 
Informed Consent ...................................................................................................... 17 
5.9.1. Associated Risks and Benefits to Subjects ........................................................... 17 
5.10. Visit schedule .............................................................................................................. 19 
5.10.1. Pre-Study Screening and Baseline Evaluation .................................................... 19 
5.10.2. Treatment/Assessment Visits ................................................................................ 20 
5.11. Study procedures ........................................................................................................ 22 
5.11.1. Safety of Study procedures ................................................................................... 27 
5.12. Washout Period .......................................................................................................... 28 
5.13. Blinding and Randomization .................................................................................... 28 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
5
5.14. Premature Withdrawal/Discontinuation Criteria ................................................... 28 
6. 
Investigational Product .............................................................................................. 29 
6.1. 
Formulation ................................................................................................................ 29 
6.2. 
Dosage Regimen ......................................................................................................... 29 
6.3. 
Administration ........................................................................................................... 29 
6.4. 
Labelling ..................................................................................................................... 30 
6.5. 
Storage ......................................................................................................................... 31 
6.6. 
Accountability ............................................................................................................. 31 
6.7. 
Concomitant Medications .......................................................................................... 31 
7. 
Assessment of Efficacy ............................................................................................... 32 
7.1. 
Primary Outcome ....................................................................................................... 32 
7.2. 
Secondary Outcomes .................................................................................................. 32 
8. 
Assessment of Safety .................................................................................................. 33 
8.1. 
Definitions ................................................................................................................... 33 
8.1.1. Adverse Events ..................................................................................................... 33 
8.1.2. Serious Adverse Events ........................................................................................ 33 
8.2. 
Reporting Procedures for SAEs ................................................................................ 34 
8.2.1. GSK Reporting Procedures.................................................................................. 34 
8.3. 
Adverse Events with Mepolizumab .......................................................................... 36 
8.4. 
AEs of Study Procedures ........................................................................................... 37 
9. 
Statistical Plan ............................................................................................................ 37 
9.1. 
Sample Size Estimation ............................................................................................. 37 
9.2. 
Statistical Analysis ..................................................................................................... 38 
9.2.1. General Considerations, Assumptions, and Definitions ...................................... 38 
9.2.2. Primary Endpoint................................................................................................. 39 
9.2.3. Secondary Endpoint ............................................................................................. 39 
9.3. 
Missing, Unused, Spurious Data ............................................................................... 39 
9.4. 
Statistical Plan Deviations ......................................................................................... 39 
10. 
Data Handling and Recordkeeping .......................................................................... 40 
10.1. Confidentiality and Security ..................................................................................... 40 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
6
10.2. Training ....................................................................................................................... 40 
10.3. Records Retention ...................................................................................................... 40 
11. 
Direct Access to Source Data/Documents ................................................................ 41 
12. 
Quality Control and Quality Assurance .................................................................. 41 
13. 
Regulatory ................................................................................................................... 42 
13.1. Ethical Considerations ............................................................................................... 42 
13.2. Research Ethics Board ............................................................................................... 42 
13.3. Ethical Conduct of the Study .................................................................................... 43 
13.4. Subject Information and Consent ............................................................................ 43 
13.5. Health Canada ............................................................................................................ 43 
13.6. Protocol Amendments ................................................................................................ 43 
13.7. Protocol Deviations .................................................................................................... 44 
14. 
Study Administration ................................................................................................ 44 
14.1. Organization and Participating Centre ................................................................... 44 
14.2. Investigators ............................................................................................................... 44 
15. 
Financing ..................................................................................................................... 45 
15.1. Funding Source .......................................................................................................... 45 
16. 
Publication Policy and Disclosure of Data ............................................................... 45 
17. 
References ................................................................................................................... 46 
Appendix 1. Leicester Cough Questionnaire ....................................................................... 50 
Appendix 2. Modified Borg Scale ......................................................................................... 51 
Appendix 3. Cough Severity Visual Analogue Scale........................................................... 52 
 
 
 
 
 
 
 
 
 
 
 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
7
 
List of Tables 
 
Table 1. Visit and procedure schedule. ........................................................................................ 26 
Table 2. Intervention, dose, form, strength, and manufacturer per intervention. ......................... 29 
Table 3. GSK reporting safety events and information procedure ............................................... 35 
Table 4. A pooled summary of adverse events in the first 24 weeks of 2 trials (MENSA and 
SIRIUS)......................................................................................................................................... 36 
Table 5. Known complications associated with study procedures conducted in this study. ........ 37 
 
 
 
 
 
List of Figures 
 
Figure 1. Study flow diagram detailing the study visits and procedures per visit per subject 
following enrolment. ..................................................................................................................... 13 
Figure 2. Injection sites for investigational product administration. ........................................... 30 
 
 
 
 
List of Abbreviations 
 
ACQ – asthma control questionnaire 
COPD – Chronic obstructive pulmonary disease 
EAR – Early asthmatic response 
EB – Eosinophilic bronchitis  
GERD – gastro-esophageal reflux disease 
ICS – Inhaled corticosteroid 
IL5 - Interleukin 5 
LAR – Late asthmatic response 
NAEB – Non-asthmatic eosinophilic bronchitis 
OCS – Oral corticosteroid 
RCT – randomized controlled trials 
REB – Research Ethics Board 
SOP – Standard operating procedure 
TRPV1 – Transient receptor potential vanilloid type-1 
WOCBP – Women of childbearing potential 
 
 
 
 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
8
1. Introduction 
 
1.1. Study Summary 
 
Cough is the most common presenting symptom to family physicians (1). Chronic Cough 
affects approximately 10-12% of the general population (2) and is one of the commonest reasons 
for referral to secondary care (3). Unfortunately, there are no licensed treatments for this 
debilitating condition, which is associated with a poor quality of life, affecting the social, 
physical and psychological well-being of patients (4). Asthma and non-asthmatic eosinophilic 
bronchitis (NAEB) are known causes of chronic cough and 30-50% of patients have evidence of 
eosinophilic airway diseases (5-7). Inhaled corticosteroids (ICS) are commonly used to treat 
cough in asthma and EB but there are no randomized controlled studies showing evidence of 
improvements in objective cough rates. Our group has recently demonstrated increased sputum 
eosinophils after allergen challenge to be associated with increased neuronal sensitivity and 
increased objectively measured cough frequency over 24 hours (8). Eosinophils have also been 
found to be co-localised with airway nerves (9). Increased airway eosinophilia in asthma and 
non-asthmatic eosinophilic bronchitis (NAEB) may be driving excessive coughing and this can 
potentially be targeted by anti-interleukin 5 (IL5) therapy. 
 
Therefore, the aim of this single centre proof-of-concept study is, for the first time, to 
investigate whether mepolizumab reduces objective cough frequency in patients with 
eosinophilic asthma and NAEB presenting with chronic cough. Secondary outcomes including 
the effects on quality of life, intensity of irritant sensations, airway hyper-reactivity and 
inflammatory cells will also be evaluated.  
 
1.2 Background and Rationale  
 
Chronic Cough – An Unmet Need 
Cough is the single most common reason for seeking medical attention (1). Many 
individuals experience acute coughing lasting up to three weeks after a viral respiratory tract 
infection.  However, approximately 10% suffer from chronic cough (lasting more than eight 
weeks) with detrimental effects on quality of life (10-12). The prevalence increases with age, but 
peaks in the 50’s and 60’s and is twice as common in females than in males (13). The typical 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
9
history is described as a non-productive cough often occurring in distressing bouts, which the 
patient cannot control, usually preceded by an irresistible urge to cough associated with an 
irritating sensation in the throat. Cough can be evoked by innocuous triggers such as changes in 
temperature, strong smells from perfumes or aerosols, dust and passive smoking (14, 15). 
Chronic cough has major psychological, social and physical consequences (16). Individuals with 
chronic cough are embarrassed socially and in the workplace. They become physically exhausted 
by the frequent prolonged coughing bouts, and women may experience stress incontinence. The 
treatment options for chronic cough are limited. In the US, over $8 billion is spent each year on 
over-the-counter cough and cold medications, most of which contain dextromethorphan which 
has very limited if any clinical effectiveness (17). Unfortunately, there are no current licensed 
treatments for chronic cough, and this represents a major clinical unmet need. 
 
Aetiology of Chronic Cough 
Chronic cough can be associated with many respiratory conditions such as asthma, 
NAEB, bronchitis in smokers and chronic obstructive pulmonary disease (COPD), where the 
cough is typically related to the pathophysiology of the underlying disease, e.g. smoking in 
COPD or excess airway mucus. Other causes include eosinophilic bronchitis, interstitial lung 
diseases, bronchiectasis or use of angiotensin-converting enzyme inhibitors. Extra-pulmonary 
diseases such as gastro-esophageal reflux disease (GERD) and post-nasal drip secondary to 
rhinosinusitis can also be identified as potential triggers. 
 
Observational studies detailing the aetiology of chronic cough in patients presenting to 
specialist cough clinics show large variations in the prevalence of asthma (6-36%), GERD (0-
41%), and rhinitis (8-56%) (18). Furthermore, up to a quarter of patients may have multiple 
aetiologies combined (19). Non-asthmatic eosinophilic bronchitis was first described in 1989 at 
McMaster University as a potential cause of chronic cough (20). However, as access to 
measuring sputum eosinophilia is limited, the prevalence of NAEB is uncertain. Studies in 
specialist clinics where assessments of airway inflammation in chronic cough patients have been 
made, report between 10-30% as having evidence of eosinophilic airways (7, 21, 22).  
 
Treatments for cough in asthma and non-asthmatic eosinophilic bronchitis 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
10
Both asthma and NAEB are associated with airway eosinophilia, but in the latter, there is 
no evidence of increased airway hyper-reactivity or variable airflow limitation, and cough is the 
predominant symptom. This has led to guidelines recommending a trial of treatment with ICS. 
However, the strength of the recommendation is weak due to a lack of evidence showing 
reduction in objective coughs rates in placebo-controlled studies (23). The use of ICS is well 
established in asthma from the large phase 3 randomized controlled trials (RCT), however, 
cough is not independently assessed in most studies, and current asthma questionnaires such as 
the asthma control questionnaire (ACQ) do not capture cough as a symptom. In patients with 
asthma or NAEB, use of inhaled corticosteroids can also make coughing worse, occasionally 
leading to use of low-dose oral corticosteroids. This can result in long term side effects which are 
intolerable to patients.  
 
Airway Nerves, Eosinophils and Cough 
Cough is the archetypal airway defensive reflex mediated by sensory afferents of the 
parasympathetic vagus nerves and its receptor profile on the nerve terminals. Activation of two 
main sub-types of sensory vagal afferent nerves is responsible for evoking cough (24):  
 
I. 
C fibres: networks of un-myelinated nerves found throughout the airways, sensitive to 
chemical stimuli including inflammatory mediators (e.g. bradykinin, prostaglandins) and 
environmental stimuli (e.g. pollutants, temperature). These nerves can be activated by 
capsaicin, a specific agonist of transient receptor potential vanilloid type-1 (TRPV1)  
 
II. 
A-delta fibres: proximal airways are also innervated by sub-epithelial myelinated nerves 
also known as ‘cough receptors’, as they evoke cough. They respond to punctate 
mechanical stimuli, low osmolarity and acidity. 
 
To directly assess the role of airway eosinophils in asthma, coughing and neuronal 
sensitivity, we previously performed whole lung allergen challenge in patients with mild steroid 
naïve atopic asthma who demonstrated both an early and late asthmatic response (EAR/LAR) to 
inhaled allergen (8). We showed that capsaicin evoked coughs increased during the early 
asthmatic response but also remained heightened 24 hours after allergen when 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
11
bronchoconstriction had resolved. This heighted cough response was associated with an increase 
in sputum eosinophils from 3% to 15% and also increased objective hourly cough frequency. 
This suggests that in individual patients, an increase in airway eosinophilia, increases neuronal 
sensitivity which enhances the cough reflexes, resulting in an increase in spontaneous coughs. 
How eosinophils actually sensitise airway nerves is still unknown, however recent wholemount 
imaging studies in moderate to severe asthmatics has shown greater co-localisation of 
eosinophils and airway nerves in patients with moderate-severe asthma compared with healthy 
controls and patients with mild asthma (9). Furthermore, in an animal model, eosinophils 
mediated an increase in nerve density (9).  
 
Mepolizumab as a treatment for chronic cough in eosinophilic airways diseases 
Mepolizumab is a humanised monoclonal antibody against IL-5, which is currently 
licensed for treatment in patients with severe uncontrolled exacerbations. Interleuklin-5 is a key 
cytokine controlling eosinophil growth, differentiation, recruitment, activation and survival (25-
27).  Treatment with mepolizumab results in a reduction in serum eosinophils and sputum 
eosinophils (28, 29). The main clinical benefits are in the reduction in exacerbations requiring 
treatment bursts of oral corticosteroids (OCS) and/or hospitalisations by approximately 50-60% 
(29, 30). There have been no studies which have recruited patients with chronic cough or 
assessed objective cough frequency as a study outcome with anti-IL5 therapy. 
 
Therefore, the aim of this study is to evaluate the effectiveness of mepolizumab for the 
treatment of chronic cough in patients with eosinophilic airways disease, including both asthma 
and NAEB.  
 
2. Hypothesis 
 
We hypothesise that in patients with asthma and NAEB, eosinophils are involved in 
sensitising airway nerves and thereby increasing spontaneous objective coughs. We therefore 
predict that treatment with mepolizumab will reduce airway eosinophilia in patients with chronic 
cough due to eosinophilic asthma and NAEB, thereby causing a reduction in objective cough 
frequency. 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
12
3. Study Aim  
 
This is a proof-of-concept study to investigate if anti-IL-5 treatment aimed at reducing 
airway eosinophilia causes a reduction in objective cough frequency.  
4. Study Objectives 
 
Primary Objectives: 
In patients with refractory chronic cough with airway eosinophilia to measure the effects 
of mepolizumab on 24-hour objective cough frequency.  
 
Secondary Objectives: 
 
1. To determine the effects of mepolizumab on: 
 
i. 
Awake /Night-time cough frequency 
ii. 
Intensity of irritant sensations 
iii. 
Quality of life 
iv. 
Airway hyper-responsiveness 
v. 
Inflammatory cells  
 
All the above secondary objectives will also be analysed based on disease group, i.e., asthma and 
NAEB. 
 
2. The relationship between change in cough frequency and change in eosinophils 
 
 
5. Study Design 
 
5.1. Design 
 
This is a 9-visit randomized, double-blind, placebo controlled, parallel group study 
evaluating the effectiveness of 4 doses of mepolizumab for the treatment of refractory chronic 
cough in patients with eosinophilic airways disease (Figure 1). We plan to complete 15 subjects 
in each arm of the clinical trial. The duration of intervention will be 12 weeks, during which 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
13
subjects will receive 4 doses at days 0, 28, 56 and 84. The effects of mepolizumab on objective 
cough frequency will be tested at week 14, 2 weeks following the last dose of 
mepolizumab/placebo. 
 
Figure 1. Study flow diagram detailing the study visits and procedures per visit per subject 
following enrolment. 
 
5.2. Duration of Study 
 
The total length of a subject’s participation in the trial is up to 16 weeks; 
• Up to 2 weeks screening period 
• 14-week intervention period 
 
5.3. Number of Sites 
 
1. McMaster University, 1200 Main St West, Suite 3U31 
Hamilton, Ontario, Canada, L8N 3Z5 
 
5.4. Study Period 
 
Estimated date of first subject Q2 2021 
Estimated date of last subject Q4 2022 
 
5.5. Study Population 
 
Male and female patients ≥ 18 years of age assessed in a secondary care clinic for chronic 
cough due to asthma and/or NAEB. 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
14
 
5.6. Inclusion Criteria 
 
The following inclusion criteria must be met for patients to enter the screening phase of the 
study: 
1. Male sex and female sex patients 
2. Aged ≥18 
3. Subjects with a history of chronic cough (cough lasting for >8 weeks) 
4. Evidence of airway eosinophilia (sputum eosinophilia2%) 
5. FEV1 ≥ 70% of predicted 
6. Normal chest x-ray (within the last 2 years) 
7. At least one dose of a COVID-19 vaccine a minimum of 2 weeks prior to enrollment 
 
5.7. Exclusion Criteria 
 
Patients should not enter the study if any of the following exclusion criteria are fulfilled: 
1. Symptoms of upper respiratory tract infection in the last 1 month which have not 
resolved. 
2. Lower respiratory tract infection or pneumonia in the last 1 month. 
3. Subjects with a positive covid-19 test within 2 weeks of screening 
4. Subjects with seasonal allergic rhinitis that affects their asthma control  
5. Current smoker or ex-smoker with ≥20 pack year smoking history and abstinence of ≤6 
months 
6. Symptoms of uncontrolled asthma at screening defined as: an exacerbation in the 
previous month requiring oral prednisone or antibiotics. 
7. Use of regular maintenance oral corticosteroids or long-acting muscarinic antagonist 
within 4 weeks prior to enrolment into the study.  
8. A previous asthma exacerbation requiring Intensive Care Unit admission. 
9. Significant other primary pulmonary disorders in particular; pulmonary embolism, 
pulmonary hypertension, interstitial lung disease, lung cancer, cystic fibrosis, emphysema 
or bronchiectasis. 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
15
10. Any history or symptoms of uncontrolled cardiovascular disease, particularly coronary 
artery disease, uncontrolled arrhythmias, uncontrolled hypertension, or uncontrolled 
congestive heart failure. 
11. Any history or symptoms of significant neurologic disease, including transient ischemic 
attack, stroke, seizure disorder, or behavioral disturbances 
12. Uncontrolled diabetes 
13. End stage kidney or liver disease 
14. Clinically significant abnormalities in laboratory test results during the screening period 
(including complete blood count, coagulation, electrolytes, liver function tests) unless 
deemed not significant by the investigator. 
15. Any history or symptoms of clinically significant autoimmune disease 
16. History of anaphylaxis to any biologic therapy or vaccine 
17. History of Guillain-Barre Syndrome 
18. A helminth parasitic infection diagnosed within 24 weeks prior to the date of informed 
consent is obtained that has not been treated with or has failed to respond to standard of 
care therapy. 
19. Positive hepatitis B surface antigen, or hepatitis C virus antibody serology, or a positive 
medical history for hepatitis B or C. Subjects with a history of hepatitis B vaccination 
without history of hepatitis B can enroll. 
20. A history of immunodeficiency disorders including a positive human immunodeficiency 
virus test (HIV) 
21. Pregnancy or breast-feeding.  
22. Women of childbearing potential (WOCBP) must not be actively seeking pregnancy, and 
must use an effective form of birth control (confirmed by the Investigator). Effective 
forms of birth control include: true sexual abstinence, a vasectomized sexual partner, 
Implanon, female sterilization by tubal occlusion, any effective IUD intrauterine 
device/IUS levonorgestrel Intrauterine system, Depo-Provera™ injections, oral 
contraceptive, and Evra Patch™ or Nuvaring™. WOCBP must agree to use an effective 
method of birth control, as defined above, from enrolment, throughout the study duration 
and within the 8 treatment weeks. They must demonstrate a negative serum pregnancy 
test at screening and demonstrate a negative urine pregnancy test immediately before 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
16
each dose of study drug or placebo. Women not of childbearing potential are defined as 
women who are either permanently sterilized (hysterectomy, bilateral oophorectomy, or 
bilateral salpingectomy), or who are postmenopausal.  Women will be considered 
postmenopausal if they have been amenorrheic for 12 months prior to the planned date of 
randomization without an alternative medical cause.  The following age-specific 
requirements apply: 
i. Women <50 years old would be considered postmenopausal if they have 
been amenorrheic for 12 months or more following cessation of 
exogenous hormonal treatment and follicle stimulating hormone (FSH) 
levels in the postmenopausal range. 
ii. Women ≥50 years old would be considered postmenopausal if they have 
been amenorrheic for 12 months or more following cessation of all 
exogenous hormonal treatment. 
23. Male patients not using an acceptable method of contraception. All male patients who are 
sexually active must agree to use an acceptable method of contraception (condom with or 
without spermicide, vasectomy) from the first dose of study drug until their last dose. 
24. Use of angiotensin-converting-enzyme inhibitors 
25. Use of immunosuppressive medication (including but not limited to: methotrexate, 
cyclosporine, azathioprine, intramuscular long-acting depot corticosteroid, oral 
corticosteroid, or any experimental anti-inflammatory therapy) within 3 months prior to 
the date informed consent is obtained 
26. Use of any other biological within 4 months or 5 half-lives prior to randomization, 
whichever is longer.   
27. Any centrally acting medication within the last 2 weeks which in the view of the 
investigator could influence the coughing*   
28. History of psychiatric illness, drug or alcohol abuse which may interfere in the 
participation of the trial. 
 
*Any participant who is taking amitriptyline, dextromethorphan, pregabalin, gabapentin or 
opioids will not be eligible to take part in this study unless they are willing and medically able to 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
17
withdraw from such medication for the duration of the study.  The reason for this is that centrally 
acting medications may influence coughing rates. 
 
5.8. Recruitment Process 
 
Participants will be recruited by clinicians from clinics at either of the following sites: 
a) McMaster University Medical Centre, Department of Respiratory Medicine, 1280 Main 
St. West, Hamilton, Ontario, Canada, L8S 4K1 
b) Firestone Institute for Respiratory Health, St Joseph’s Healthcare, 50 Charlton Ave E, 
Hamilton, ON L8N 4A6 
All study visits will take place at McMaster University, Cardio-Respiratory Research 
Laboratory, Faculty of Health Sciences, 3U31, 1280 Main St. West, Hamilton, Ontario, Canada, 
L8S 4K1. 
 
5.9. Informed Consent 
 
Patients recruited to participate in the study will meet with study staff and receive the 
participant information sheet. Patients will be given the opportunity to ask study staff questions 
about the study. Patients who express an interest in participating in the study will provide their 
fully informed written and verbal consent to be enrolled in the study. Informed consent will be 
obtained at the screening visit before any study procedures are conducted. Patients will also be 
informed that mepolizumab is currently licensed in Canada for treatment of patients with severe 
eosinophilic asthma only. If a patient’s chronic cough improves whilst on the active treatment, 
mepolizumab is currently not licensed from the treatment of chronic cough.  
 
5.9.1. Associated Risks and Benefits to Subjects 
 
Benefits 
Subjects will benefit from regular assessment of lung physiology, blood and airway 
inflammation and cough frequency. Along with helping to advance our understanding of the 
mechanisms causing chronic cough and to develop potentially improved treatments, the subject 
will benefit from being reviewed by a chest specialist.  
 
Risks 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
18
The common risk of treatment with mepolizumab from placebo-controlled studies is local 
injection site reaction. In 2 placebo-controlled studies the incidence of local injection site 
reactions with mepolizumab 100 mg subcutaneous and placebo was 8% and 3%, respectively. 
These events were all non-serious, mild to moderate in intensity and the majority resolved within 
a few days. Local injection site reactions occurred mainly at the start of treatment and within the 
first 3 injections with fewer reports on subsequent injections. The most common manifestations 
reported with these events included pain, erythema, swelling, itching, and burning sensation. A 
full list of adverse events are tabulated in section 8.3 below. 
 
It is possible that subjects may develop an increase in their asthma symptoms during the 
with-holding of asthma medication before the methacholine challenge on visit 1. Should this 
happen, patients will be advised to re-start their medication and inform the principle investigator. 
There will be an on-call study physician who is contactable outside of working hours should 
advice be needed.  
 
The main risk of performing a methacholine challenge is that of developing asthma 
symptoms, due to the fall in FEV1. The American Thoracic Society (ATS) has published a 
detailed guideline for performing methacholine challenge, which we have adopted for our local 
standard operating procedure (SOP) to maintain international standards (31).  
 
Sputum induction using hypertonic saline carried a small risk of a fall in lung function 
along with a salty unpleasant taste at the back of the mouth.  
 
Precautions will be taken for patient safety such as the availability of monitoring 
equipment (spirometer, pulse oximeter, blood pressure monitor) and short acting bronchodilators 
(salbutamol and ipratropium via inhaler/nebuliser), oxygen, and resuscitation equipment. 
 
Risk of contracting COVID-19 infection during study participation 
 
As long as the COVID-19 pandemic is ongoing, there is a risk of contracting a SARS-CoV-2 
infection during the time period of study participation. Participants will be asked about 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
19
symptoms and risks of COVID-19 infection prior to each study visit and on the day of the study 
visit.  Participants who are at high risk will be asked to have a COVID-19 test performed at a 
local public health lab and must have received a negative test prior to attending the study site.   
Participants will be asked further information regarding symptoms suggestive of COVID-19 
infection as part of the screening visit and subsequent visits (as applicable in accordance with 
guidance from the relevant regional and local public health authorities). Participants must not 
have had a positive test within 2 weeks of the screening visit.  If a participant received a COVID-
19 positive test during study participation, the investigator will have to decide whether remaining 
in the study is compatible with participant’s and site personnel’s safety and well-being. 
 
5.10. Visit schedule 
 
5.10.1. Pre-Study Screening and Baseline Evaluation 
 
Prior to visit 1, all subjects will be provided with the Information Letter related to COVID-19 
and asked to complete the Ontario Covid-19 Assessment Tool 24 hours and 1 hour prior to 
scheduled study visit. 
 
Visit 1: Screening 
Recruited patients will be invited to attend Visit 1 to undergo study screening. All subjects will 
undergo Ontario Covid-19 Assessment Tool and Information Letter. Patient eligibility will be 
assessed against the study inclusion/exclusion criteria and patients will undergo informed 
consent. Subjects who provide informed consent and are enrolled into the study will undergo 
screening procedures: complete medical history, physical examination, methacholine challenge, 
spirometry sputum induction, and blood sampling. Subjects will complete the Leicester Cough 
Questionnaire, the modified Borg Scale, and Cough Severity Visual Analogue Scale (VAS, 0-
100mm) to assess severity and intensity of cough sensations including urge to cough, throat itch, 
throat tickle, and throat irrigation. If the sputum quality obtained during the screening visit is 
deemed of poor quality, then the subject will be requested to repeat the sputum induction 
procedure  within 14 days of visit 1 to ensure an adequate sample is obtained for assessment. 
Following the screening visit, subjects will be booked into the 8 remaining study visits and 
randomized into the intervention (mepolizumab) arm or placebo arm. Subjects will be scheduled 
to return for Visit 2 within 2 weeks of the screening visit.  

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
20
 
5.10.2. Treatment/Assessment Visits 
 
Visit 2: Baseline Cough Monitoring 
All subjects will undergo Ontario Covid-19 Assessment Tool and Information Letter prior to 
study visit. Enrolled subjects will wear an ambulatory cough monitor for 24 hours and be 
scheduled to return the following day for Visit 3.  
 
Visit 3: Week 0 Administration of Mepolizumab/Placebo (1st Injection) 
All subjects will undergo Ontario Covid-19 Assessment Tool and Information Letter prior to 
study visit. Subjects will return with the cough monitor 24 hours following Visit 2. If no 
recording was obtained during the past 24 hours due to recording device malfunction (such as 
battery or card failure) then the subject will be asked to repeat the recording within 24-48 hours 
of prior attempt at recording. Subjects will undergo spirometry, sputum induction, and blood 
sampling and complete the Leicester Cough Questionnaire, the modified Borg Scale, and the 
Cough Severity VAS to measure the severity and intensity of cough sensations. Urine will be 
collected in WOCBP to screen for pregnancy. The first injection of mepolizumab/placebo will be 
administered in the clinical research facility by a study physician. The subject will be observed 
for a minimum of 1 hour for the appearance of any acute drug reactions.  
 
Visit 4: Week 4 Administration of Mepolizumab/Placebo (2nd Injection) 
All subjects will undergo Ontario Covid-19 Assessment Tool and Information Letter prior to 
study visit. Subjects will return to the clinical research facility 4 weeks following Visit 3. 
Subjects will undergo blood sampling and complete the Leicester Cough Questionnaire, the 
modified Borg Scale, and the Cough Severity VAS. Urine will be collected in WOCBP to screen 
for pregnancy. The second injection of mepolizumab/placebo will be administered in the clinical 
research facility by a study physician. The subject will be observed for a minimum of 1 hour for 
the appearance of any acute drug reactions.  
 
Visit 5: Week 8 Cough Monitoring and Administration of Mepolizumab/Placebo (3rd 
Injection) 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
21
All subjects will undergo Ontario Covid-19 Assessment Tool and Information Letter prior to 
study visit. Subjects will return to the clinical research facility 4 weeks following Visit 4. Urine 
will be collected in WOCBP to screen for pregnancy. The third injection of 
mepolizumab/placebo will be administered in the clinical research facility by a study physician. 
The subject will be observed for a minimum of 1 hour for the appearance of any acute drug 
reactions. Subjects will wear an ambulatory cough monitor for 24 hours and be scheduled to 
return the following day for Visit 6. 
 
Visit 6: Assessment of Blood, Sputum and Questionnaires 
All subjects will undergo Ontario Covid-19 Assessment Tool and Information Letter prior to 
study visit. Subjects will return with the cough monitor 24 hours following Visit 5. If no 
recording was obtained during the past 24 hours due to recording device malfunction or if the 
recording quality is deemed poor, then the subject will be asked to repeat the recording within 
24-48 hours of prior attempt at recording. Subjects will undergo spirometry, blood sampling and 
sputum induction and complete the Leicester Cough Questionnaire, the modified Borg Scale, and 
the Cough Severity VAS.  
 
Visit 7: Week 12 Administration of Mepolizumab/Placebo (4th Injection) 
All subjects will undergo Ontario Covid-19 Assessment Tool and Information Letter prior to 
study visit. Subjects will return to the clinical research facility 4 weeks following Visit 6. 
Subjects will undergo blood sampling and complete the Leicester Cough Questionnaire, the 
modified Borg Scale, and the Cough Severity VAS. Urine will be collected in WOCBP to screen 
for pregnancy. The fourth injection of mepolizumab/placebo will be administered in the clinical 
research facility by a study physician. The subject will be observed for a minimum of 1 hour for 
the appearance of any acute drug reactions. 
 
Visit 8: Week 14 Cough Monitoring  
All subjects will undergo Ontario Covid-19 Assessment Tool and Information Letter prior to 
study visit. Subjects will wear an ambulatory cough monitor for 24 hours and be scheduled to 
return the following day for Visit 9. 
 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
22
Visit 9: Final Visit: Assessment of Blood, Sputum and Questionnaires 
All subjects will undergo Ontario Covid-19 Assessment Tool and Information Letter prior to 
study visit. Subjects will return with the cough monitor 24 hours following Visit 8. If no 
recording was obtained during the past 24 hours due to recording device malfunctionthen the 
subject will be asked to repeat the recording within 24-48 hours of prior attempt at recording. 
Subjects will undergo spirometry, methacholine challenge, blood sampling and sputum induction 
and complete the Leicester Cough Questionnaire, the modified Borg Scale, and the Cough 
Severity VAS. 
  
5.11. Study procedures 
 
All study procedures will be conducted by appropriately trained and experienced staff and 
supervised by a medical doctor familiar with the protocol and the experimental techniques and 
who will be available at all times. Participants will be asked to refrain from consuming caffeine 
at least 2 hours prior to each visit, and to refrain from taking any salbutamol 4-6 hours before 
study visits. All procedures listed will be performed according to local standard operating 
procedures (SOPs)(Table 1). All data produced from study procedures will be documented on 
CRFs, which will be considered source documents.  
 
A. Spirometry:  
During a spirometry manoeuvre, participants are asked to inhale maximally then blow out 
with maximal force into the spirometer until all air from the lungs has been expelled. The 
two main physiological measures derived from spirometry are FEV1 and FVC, both 
expressed in litres. FEV1 is the volume of air exhaled in the first second of forced 
expiration. FVC is the total volume of air exhaled with maximally forced effort. Volumes 
will be recorded at body temperature–prevailing atmospheric pressure–water vapour 
saturation. Spirometry in this study will be performed according to ATS and European 
Respiratory Society (ERS) standards.  
 
B. Blood Sampling: 
Blood will be collected from subjects during Visits 1, 3, 4, 6, 7 and 9. At visits 1 blood 
will be taken to assess for complete blood count for blood eosinophils and to ensure no 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
23
other clinically significant liver, electrolyte disorders or infections (HIV, Hepatitis B and 
C). Blood will be collected at Visits 3, 4, 6, 7 and 9 for complete blood count, liver 
enzymes, and electrolytes. Blood will be collected at Visits 3 (pre-treatment) and 9 (post-
treatment) for total, activated mature eosinophils, eosinophil progenitors (assessed by 
flow cytometry) and related transcriptomics. Remaining plasma from blood processing 
and sputum at Visit 1 will be analysed to fully characterise type 2 inflammation.   
 
C. Objective Cough Monitoring: 
Participants will be asked to wear an ambulatory cough monitor (VitaloJAKTM, 
Vitalograph, UK) for 24 hours, 3 times during the study: Visits 2, 5 and 8. This involves 
attaching an air microphone to the lapel of the clothing and a chest sensor on the sternum. 
The VitaloJAK cough recorder is worn around the waist of the subject. Subjects will 
wear the cough monitor for a continuous 24 hours and return the following day for the 
procedures for the next visit. Subjects will be informed not to have a shower during this 
period to prevent the air microphone and chest sensor being damaged by water. 
 
The VitaloJAK cough monitor is a non-invasive, battery operated, and custom-built 
validated recording device and microphone intended to acquire, record and store 
ambulatory cough sounds from participants for 24 hours. Briefly, this consists of a digital 
data logger recording sounds at a sample rate of 8 kHz, with 16-bit resolution and in 
Waveform Audio File format, which is a commonly used uncompressed sound file 
format. Recordings will be transferred to a personal computer; silences and background 
noise will be removed by using validated, custom-written software, and cough sounds 
will be counted by using an audio editing package. The number of coughs will be 
expressed as coughs per hour and added up to give a cough count for a 24-hour period, 
awake cough frequency, and night-time cough frequency.  
 
The cough monitor is an audio recording device and will record all sound including 
conversations. The cough monitor microphones capture speech in the local vicinity in 
addition to cough sounds. Therefore, it is possible that despite processing of the cough 
recording by customised software, some of the participant’s conversations are also 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
24
captured in addition to their cough sounds. The recordings will be processed using an 
algorithm which compresses the recording and removes any non-cough sounds. On 
occasion the recordings may capture non-cough sounds which will require sound analysis 
by a cough analyst. The recordings will be sent outside of McMaster to be processed by 
an analyst who will be bound by a strict duty of confidentiality not to disclose any 
information heard. A central analyst is required for data consistency and accuracy. 
Vitalograph Ltd. (Maids Moreton Bukingham, England, Mk18 1SW) will act as the 
external vendor responsible for processing the cough monitor audio recordings. Prior to 
enrolment in the trial, this possibility will be explained to the subjects. Any conversations 
recorded would be treated with the usual standards of confidentiality as per GCP 
guidelines. Confidentially will be maintained so long as the analyst does not hear any 
recordings suggesting the participant may harm themselves or someone else. The cough 
monitor has a mute button to allow sensitive personal conversations to be muted. If any 
personally sensitive information become apparent during the cough counting process, 
then these will be deleted out.  
 
D. Methacholine Challenge Test 
Methacholine is a synthetic form of acetylcholine and therefore causes smooth muscle 
contraction. It is commonly used in clinical practice to exclude asthma, but also as a 
measure of airway hyper-responsiveness. It involves giving nebulised methacholine in 
doubling concentrations from 0.0625 mg/mL up to 16 mg/ml via the 2-minute tidal 
breathing method. At each concentration, FEV1 is measured 30s and 90s after the end of 
each inhalation. The % fall in FEV1 from baseline is calculated after each dose using the 
best FEV1 and the test is terminated once a 20% fall in FEV1 (PC20) is documented or 
the maximum concentration of 32 mg/mL is reached. Patients with a methacholine 
PC20<16mg/ml will be considered to have asthma. The methacholine PC20 will be 
assessed at Visit 1 and Visit 9. Information about which medication to stop prior to the 
test will be given to the patient. 
 
E. Sputum Induction:  

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
25
Prior to performing the sputum induction, spirometry will be repeated to ensure FEV1 has 
returned to within 10% of the baseline prior to the methacholine challenge test. This may 
require 200-400mcg of salbutamol in addition to the post-methacholine challenge test 
salbutamol. The purpose is to induce sputum from the airways by giving nebulised 
hypertonic saline (3%/5%/7%) in incremental doses for a 7 min interval, provided the 
FEV1 does not fall by more than 20% drop from pre-sputum baseline. If there is a drop in 
FEV1 between 10-20% then a lower saline concentration (0.9%, 3%, 5%) will be 
administered. If the FEV1 drops by ≥20% then sputum induction will be stopped and 
salbutamol via inhaler or nebuliser will be given to bring the FEV1 to at least 90% of the 
baseline pre-sputum FEV1. Once sputum is collected in a sterile pot, it will be put on ice 
and sent to the laboratory for total, differential cell count, eosinophil free granules. 
Remaining cells from sputum processing on Visits 3 and 9 will be used to determine total 
and activated mature eosinophils by flow cytometry. Remaining supernatant from sputum 
processing at Visit 1 will be stored and used to analyse neuro-inflammatory cytokines 
and protein biomarkers at a later date.   
 
F. Questionnaires: 
i) Ontario Covid-19 Assessment Tool and Information Letter 
In light of the current global COVID-19 pandemic, Canadian public health authorities 
have strongly recommended that everyone take additional precautions, including those 
outlined in the Information Letter, which will be provided to every participant via email 
before they start this study, and in person at every visit to the research laboratory. This 
Information Letter will be signed by each participant at every visit before any procedures 
take place. The day before, and one hour before every study visit, a member of the study 
team will ask each participant to complete the Ontario Covid-19 self-assessment tool and 
confirm that the result indicates that “you do not seem to have symptoms or be part of an 
at-risk group”, using the participants preferred contact method (phone, text, email). If this 
is not the case, the participant will be asked to contact the research team to reschedule 
their appointment. McMaster University is attempting to limit the risk of exposure to 
COVID-19 by using reasonable efforts to follow the health and safety guidelines 
recommended by the provincial and federal health authorities. Nevertheless, there 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
26
remains a risk that by attending McMaster University campus or any of the McMaster 
University study sites, the participant may contract COVID-19. COVID-19 can result in 
severe illness, medical expenses, loss of income and death. 
ii) The Leicester Cough Questionnaire is a patient-reported questionnaires conducted on 
Visits 1, 3, 4, 6, 7 and 9. The LCQ is a 19-item questionnaire on a 7-point Likert scale 
ranging from 1 (all of the time) to 7 (none of the time) used to assess the impact of 
chronic cough on patients using a recall period of 2 weeks. The 19 questions assess 
impact on psychological, social and physical domains (Appendix 1). 
iii) The modified Borg Scale is a patient-reported questionnaire reported on Visits 1, 3, 4, 
6, 7 and 9 and will be used to assess the intensity of sensations and self-perceived cough 
severity related to cough over a 2-week period; cough severity, urge to cough, throat itch, 
tickle, and irritation. The scale ranges from 0-10, where words are linked with numbers 
on a logarithmic scale (Appendix 2). 
iv) The Cough Severity Visual Analogue Scale (0-100mm) is a single item that assesses a 
patient’s severity of cough over a recall period of 1 week using a 0 to 100mm horizontal 
visual analogue scale (VAS). Participants will rate their severity of cough on the scale 
which has a minimum value of 0 equalling “no cough” and a maximum value of 100 
equalling “worst cough”. A higher score indicates greater cough severity. 
 
Table 1. Visit and procedure schedule. 
Visit 
1 
2 
3 
4 
5 
6 
7 
8 
9 
Study Day 
1 
13±7
* 
14±3† 42±3† 
70±3
† 
71±3
† 
99±3† 
113±7† 114±3† 
Post-Randomization 
-14 
-1 
0 
28 
56 
57 
84 
98 
99 
Week 
-2 
 
0 
4 
8 
 
12 
14 
 
Procedure 
 
 
 
 
 
 
 
 
 
Ontario Covid-19 
Assessment Tool 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Informed Consent 
X 
 
 
 
 
 
 
 
 
Medical History 
X 
 
 
 
 
 
 
 
 
Adverse Events 
 
X 
X 
X 
X 
X 
X 
X 
X 
Prior and Con Meds 
 
X 
X 
X 
X 
X 
X 
X 
X 
Examination 
X 
 
 
 
 
 
 
 
 
Vital Signs 
X 
X 
X 
X 
X 
X 
X 
X 
X 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
27
Urine B-HCG¥ 
X 
 
X 
X 
X 
 
X 
 
 
Spirometry 
X 
 
X 
 
 
X 
 
 
X 
Cough Monitoring 
 
X 
 
 
X 
 
 
X 
 
Methacholine PC20 
X 
 
 
 
 
 
 
 
X 
Induced Sputum 
X≠ 
 
X 
 
 
X 
 
 
X 
Blood Sampling 
X 
 
X 
X 
 
X 
X 
 
X 
LCQ 
X 
 
X 
X 
 
X 
X 
 
X 
mBorg Scale 
X 
 
X 
X 
 
X 
X 
 
X 
Cough Severity VAS 
X 
 
X 
X 
 
X 
X 
 
X 
Mepolizumab/Placebo 
 
 
X  
X 
X 
 
X 
 
 
* May be shortened to 7 days or extended to 21 days depending on availability of sputum cell counting to confirm 
eligibility of sputum eosinophilia >2%. 
†Flexibility provided to allow visits cough monitoring on Friday and subsequent visit on Monday. 
¥ Urine pregnancy test will be done for women of childbearing potential (WOCBP) prior to administration of IP. 
≠Sputum induction at visit 1 could be repeated after 24-48 hours if insufficient sample at visit 1. 
 
 
 
5.11.1. Safety of Study procedures 
 
Methacholine challenge testing has been used extensively both as a clinical tool in 
diagnosing asthma but also as a research tool to measure airway hyper-responsiveness. 
Methacholine acts directly on bronchial smooth muscle and causes bronchoconstriction. Most 
patients have no symptoms at all or transient symptoms whilst performing this challenge which 
improve within 24 hours. In a 1000 patient multi-centre COPD trial using methacholine 
challenge, 25% had cough, 21% had dyspnoea, 10% had wheezing, 6% had dizziness, and 2% 
had headache after the test, with two-thirds reporting no symptoms. They were asymptomatic on 
leaving the trial centre on the visit day and only 0.3% had symptoms such as chest soreness in 
the days after the test (32).  
 
Vlachos-Mayer H et al (33) retrospectively analyzed the safety of sputum induction in 304 
patients with asthma and 25 with smoking related chronic airflow obstruction. Sputum induction 
protocols varied according to baseline FEV1 (<70% or ≥70%) but they found it was safe even 
amongst patients with an FEV1 of <60% and <1 L, provided that safety precautions similar to 
that of methacholine challenge testing are taken. Fahy et al (34) also showed the safety and 
reproducibility of combining methacholine challenge testing with sputum induction immediately 
afterwards twice within 1 week with moderate to severe asthmatics. Furthermore, Mulder et al 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
28
(35) showed repeatedly performing sputum induction at 4, 7 and 24hrs after a MCT was safe and 
well tolerated. 
 
5.12. Washout Period 
 
This study does not have a washout period because this is a parallel group study design.  
 
  
5.13. Blinding and Randomization 
 
Subjects will be assigned to one of the two possible treatment arms generated by a computer-
generated randomisation schedule prepared by McMaster University, with a ratio of 1:1, 
mepolizumab or placebo. As there is a known imbalance in the prevalence and cough rates, the 
study will include sex as a randomisation factor. This will mitigate the possibility of the 
intervention being confounded by sex differences in the 2 arms of the study. Blinded study drug 
supplies will be provided in sequentially numbered identical syringes in accordance with the 
randomisation schedule and dispensed by a pharmacist who shall not be delegated any other role 
in the study. Subjects, investigators, research staff (with the exception of the pharmacist) and the 
sponsor will be masked to the treatment sequence assignment. A sealed code-break envelope for 
each subject containing details of the treatment allocated will be kept in a locked safe at the 
study site. 
 
5.14. Premature Withdrawal/Discontinuation Criteria 
 
 
During the process of informed consent, participants will be informed that they may 
withdraw from the study at any time voluntarily without giving any reason and without their 
medical care or legal rights being affected. If a participant decides to withdraw from the study 
early, the data collected will be retained with their permission.  If the participant declines to give 
permission for the data collected to be retained, it will be destroyed.   
 
 
It is also possible that patients may develop an upper respiratory tract infection and as a 
result the subjects will be withdrawn. If this occurs, then the participant will be offered a re-
screen after 4 weeks from the end of symptoms. 
 
The study may be terminated if there is a determination of futility. 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
29
 
6. Investigational Product  
 
 
6.1. Formulation 
 
All investigational products will be manufactured in accordance with Good Manufacturing 
Practice (GMP). Mepolizumab and placebo will be supplied by GSK in 1ml pre-filled syringes 
(Table 2). Mepolizumab 100mg or a normal (0.9%) saline placebo subcutaneous injection will be 
administered at the study centre on days 0, 28, 56 and 84 during the 12 week treatment period. 
The placebo will have an appearance identical to that of the study drug. Those administering 
treatment, any study staff involved in subject evaluations, and the subjects will remain blind to 
treatment assignment for the duration of the study.  
 
Table 2. Intervention, dose, form, strength, and manufacturer per intervention. 
Intervention 
Dose 
Form 
Strength 
Manufacturer 
Mepolizumab 
100mg 
pre-filled (1ml) solution in 
syringe 
100 mg/ml 
GSK 
Placebo - 0.9% 
normal saline 
N/A 
pre-filled (1ml) solution in 
syringe 
N/A 
GSK 
 
6.2. Dosage Regimen 
 
Patients will be randomized in 1:1 to receive mepolizumab 100mg monthly (4 doses) or 
matched placebo (4 doses) over 12 weeks. 
 
6.3. Administration 
 
The investigational product will be administered by an authorized study physician at 
McMaster University on study visits and within visit windows as described in study visits 
summary in section 5.6.1. Prior to administration urine pregnancy test will be done in women of 
childbearing potential to confirm the test is negative; the investigational product will only be 
administered when the result of the test is negative. The investigational product will be removed 
from the study refrigerator and sit at room temperature 30 minutes prior to administration.  
 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
30
Injections sites will be rotated such that the subjects receive the investigational product at 
different anatomical sites (Figure 2). The injection will be recorded in the source document at 
each treatment visit. After investigational product administration the subjects will be observed 
for a minimum of 1 hour for the appearance of any acute drug reactions. Appropriate 
medications such as epinephrine, antihistamines, and medical equipment to treat acute 
anaphylaxis must be available. Study personnel must be trained to recognise and treat 
anaphylaxis.  
 
Figure 2. Injection sites for investigational product administration.  
 
 
6.4. Labelling 
 
Labelling will be performed according to local regulations in Canada by pharmacist or 
another authorised person not involved in the project. Labels will include: 
• Study code 
• Investigational product/study drug dosage form, route of administration, and quantity of 
dosage units 
• Kit ID 
• Lot ID 
• Expiry date 
• Investigator name (to be written on the label) 
• Sponsor name 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
31
• Directions for use 
• Storage conditions 
• Standard statements required by Regulatory Authorities 
• Sponsor name and contact details 
 
6.5. Storage 
 
Mepolizumab/placebo will be stored at McMaster University, Cardio-Respiratory Research 
Facility, in a secure facility with limited access and controlled temperature. The temperature will 
be monitored on a daily basis and documented in a temperature monitoring log.  
 
The investigational product must be kept in the original outer container and under conditions 
specified on the label between 2–8°C (36–46°F) and protected from the light. The recommended 
storage condition and expiry dates will be provided on the product labels. 
 
6.6. Accountability 
 
The study drug provided for this study will be used only as directed in the study protocol. 
The study personnel will account for all study drugs dispensed to the patient. The study 
personnel will account for all study drugs received at the centre, unused study drugs, and for 
appropriate destruction. Certificates of delivery, destruction, and/or return should be signed. 
 
6.7. Concomitant Medications 
 
 
Patients will be allowed to have the COVID-19 vaccination before or during the whole 
study duration. Any adverse effects related to vaccination will be assessed for severity by the 
study physician. 
 
 
Patients with long standing asthma on stable doses of ICS or a combination ICS/long-
acting-beta agonists (LABA) will be allowed to continue using these medications so long as the 
dose does not change during the study. Patients with asthma who experienced an asthma 
exacerbation during the treatment period will be allowed oral prednisone, with or without 
antibiotics, as is the current standard of care. Patients with non-asthmatic eosinophilic bronchitis 
who have tried ICS or a leukotriene receptor antagonist (LTRA) but for whom cough has not 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
32
improved will not be allowed to continue using ICS and LTRA and will require a washout period 
of 28 days prior to screening. Patients with non-asthmatic eosinophilic bronchitis with partial 
relief on ICS will be allowed to continue using these medications so long as the dose does not 
change during the study. Patients on a long-acting muscarinic antagonist (LAMA) will be 
required to undergo a washout period for 28 days prior to screening. Patients using SABA or 
LABA (in an ICS combination inhaler) will be required to withhold from using the inhaler 8 and 
48 hrs prior to any methacholine challenges tests as per local SOP. 
 
 
Medications not allowed are as followed: opioids (including codeine, tramadol, 
morphine), neuromodulators (including pregabalin, gabapentin, amitriptyline), ACE inhibitors, 
immunosuppressive medication (including but not limited to: methotrexate, cyclosporine, 
azathioprine, intramuscular long-acting depot corticosteroid, oral corticosteroid, or any 
experimental anti-inflammatory therapy) within 3 months of date of informed consent, and other 
biologics within 4 months or 5 half-lives prior to date of randomization. If the subject has been 
on an opiod or an opiod like medication for a long period of time for a longstanding medical 
condition other than chronic cough, such as but not restricted to chronic pain, neuropathic pain or 
fibromyalgia, then they will be allowed to continue on their usual dosage.  
 
7. Assessment of Efficacy 
 
7.1. Primary Outcome 
 
In patients with refractory chronic cough with airway eosinophilia to measure the change in 
objective 24-hour cough frequency (coughs/hour) from baseline after 14 weeks of treatment with 
mepolizumab compared with placebo. 
 
7.2. Secondary Outcomes 
 
In patients with refractory chronic cough with airway eosinophilia to measure changes from 
baseline after 8 and 14 weeks of treatment with mepolizumab compared with placebo of: 
1. 
Awake cough frequency (coughs/hr) 
2. 
Night-time cough frequency (coughs/hr) 
3. 
Percentage of participants with a reduction in 24-hour cough frequency of ≥30% 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
33
4. 
All cough outcomes by disease group (asthma and NAEB)  
5. 
Cough severity and intensity of sensations (itch, tickle, irritation, urge to cough on 
a modified Borg Scale)  
6. 
Quality of life measured using the Leicester Cough Questionnaire (LCQ) 
7. 
Blood eosinophils 
8. 
Sputum Eosinophilia (% cell count) 
 
To determine changes from baseline after 14 weeks of treatment with mepolizumab compared 
with placebo of: 
1. 
Methacholine PC20 
2. 
Total, activated mature eosinophils, eosinophil progenitors in blood and sputum 
(Flow cytometry) and related transcriptomics. 
 
8. Assessment of Safety 
 
8.1. Definitions 
 
8.1.1. Adverse Events 
 
Adverse Events (AEs) are defined as an adverse change in health that occurs while a 
patient is taking part in a study. All AEs will be documented in the source documents and 
assessed for whether or not it is serious (see below) or expected. If not a serious adverse event 
(SAE), then the AE will be reported to McMaster University when copied into the Annual 
Progress Report if the AE was related to the study drug or a study procedure and if the event was 
unexpected.  
 
8.1.2. Serious Adverse Events 
 
Any adverse event, adverse reaction or unexpected adverse reaction, respectively, that: 
• Results in death 
• Is life threatening 
• Requires admission to hospital or prolongation of hospitalisation 
• Results in persistent or significant disability/incapacity 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
34
• Is a congenital anomaly or birth defect 
• Is otherwise medically significant 
 
8.2. Reporting Procedures for SAEs 
 
Any SAE occurring between enrolment and end of protocol follow up should be recorded in 
the subject’s hospital notes and recorded in the source documents and reported to the REB 
according to the current REB guidelines. The majority of SAEs will be expected complications 
associated with the underlying respiratory condition such as an exacerbation of asthma requiring 
hospital admission.  
 
The study drug, mepolizumab, is an off-label indication for subjects recruited for this study. 
The Principal Investigator will therefore submit expedited reports, as indicated/necessary for 
reporting of serious adverse drug reactions, by fax, directly to Health Canada.  
 
Adverse drug reactions that are both serious and unexpected are subject to expedited 
reporting to Health Canada. Expedited reporting is not required for serious events from clinical 
investigations that are considered unrelated to the study product, whether or not the event is 
expected.  
 
In accordance with Health Canada requirements, an Adverse Drug Reaction Report will be 
filed in the cases  
• where the adverse drug reaction is neither fatal nor life-threatening, within 15 days after 
becoming aware of the information.  
• where adverse drug reactions is fatal or life-threatening, immediately where possible and, 
in any event, within 7 days after becoming aware of the information;  
• within 8 days after having informed Health Canada of the adverse drug reactions, submit 
as complete as possible, a report which includes an assessment of the importance and 
implication of any findings 
 
8.2.1. GSK Reporting Procedures 
 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
35
All safety reports and associated information, including the investigator’s causality 
assessment, as presented in Table 3 that occur during the study in subjects exposed to the IP will 
be sent by email to GSK’s Case Management Group (Americas), marked for the attention of the 
Case Administrator: OAX37649@GSK.com or Fax +1-919-483-5404 and to Kirill Nikitin :  
kirill.d.nikitin@gsk.comor Fax: 919-256-5152. All safety reports will be submitted within 1 
working day of the Principal Investigator becoming aware of the event. 
 
Any SAEs reported by study subjects during the study which the investigator considers there 
to be a reasonable possibility of a causal association to any other known GSK product taken 
concurrently with the IP will be forwarded to GSK within 24 hours of the investigator becoming 
aware of the event, regardless of investigator/sponsor expectedness assessments.  
 
Further detailed information about safety reports will be submitted to GSK within 24 hours 
of follow-up information becoming available.  
 
Events exempt from reporting to GSK include any unblinded reports for subjects exposed 
only to placebo during the study.  
 
The safety reports and information that are subject to the presented GSK reporting provisions 
are those that occur following the 1st dose of the IP through to 28 days or 5 terminal phase half-
lives (whichever is longer) following discontinuation of the IP.  
 
Table 3. GSK reporting safety events and information procedure 
 
Safety Data 
Format 
Time Line 
All SAEs that are unblinded 
during the course of the 
study, for which the 
investigator considers there to 
be a reasonable possibility of 
causal association with the 
GSK IP (as specified by the 
protocol), regardless of 
Investigator/designee/Sponsor 
expectedness assessments 
against GSK IP  
Copies of Case Report Form 
pages  
Within 24 hours of Sponsor 
first unblinding the event 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
36
All SAEs that remain blinded 
on the Sponsor database 
during the course of the 
study, where the investigator 
considers there to be a 
reasonable possibility of 
causal association with the 
GSK IP (as specified by the 
protocol), regardless of 
Investigator/designee/Sponsor 
expectedness assessments 
against GSK IP.  
Copies of regulatory reports 
(e.g., CIOMS 1 or 
MedWatch) 
Retrospectively within five 
working days of the Sponsor 
unblinding the study 
database 
 
8.3. Adverse Events with Mepolizumab 
 
Local injection site reactions: In 2 placebo-controlled studies the incidence of local injection 
site reactions with mepolizumab 100 mg subcutaneous and placebo was 8% and 3%, 
respectively. These events were all non-serious, mild to moderate in intensity and the majority 
resolved within a few days. Local injection site reactions occurred mainly at the start of 
treatment and within the first 3 injections with fewer reports on subsequent injections. The most 
common manifestations reported with these events included pain, erythema, swelling, itching, 
and burning sensation. 
 
Serious adverse events: One SAE occurred in >1 patient and more frequently with 
mepolizumab than placebo: herpes zoster (2 vs 0 patients). 
 
Systemic reactions: In the 3 clinical trials, the percentages of subjects who experienced 
systemic (allergic and nonallergic) reactions were 3% for mepolizumab and 5% for placebo. 
Manifestations included rash, flushing, pruritus, headache, and myalgia. A majority of the 
systemic reactions were experienced on the day of dosing. 
 
Table 4. A pooled summary of adverse events in the first 24 weeks of 2 trials (MENSA and 
SIRIUS). 
Adverse Event 
Mepolizumab (n=263) 
Placebo (n=257) 
Headache 
19% 
18% 
Injection site reaction 
8% 
3% 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
37
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
8.4. AEs of Study Procedures 
 
Events that may be regarded as expected complications associated with the investigations are 
shown in the table below. 
 
Table 5. Known complications associated with study procedures conducted in this study.  
Procedure 
Known complications 
Spirometry 
Cough, breathlessness 
Blood Sampling 
Fainting, vasovagal events, bruising or swelling at site of 
venepuncture 
Bronchodilators 
Tachycardia, tremor, cough, nausea, headache 
Methacholine test 
Headaches, throat irritation, light headedness, chest tightness, 
breathlessness cough, wheezing 
Sputum Induction 
Nausea, vomiting, salty taste, wheeze, breathlessness, cough 
 
 
9. Statistical Plan 
 
9.1. Sample Size Estimation 
 
It is assumed that 60 subjects will be screened to randomize 30 subjects, and 15 will be 
randomized to complete each treatment arm in 1:1 ratio. This is a proof-of-concept study 
investigating the effectiveness of mepolizumab on objective cough rates in patients with 
Back pain 
5% 
4% 
Fatigue 
5% 
4% 
Influenza 
3% 
2% 
Urinary tract infection 
3% 
2% 
Abdominal pain upper 
3% 
2% 
Pruritus 
3% 
2% 
Eczema 
3% 
<1% 
Muscle spasms 
3% 
<1% 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
38
eosinophilic asthma or NAEB. As such, no formal power calculation can be currently performed. 
The sample size is therefore based on previous similar pilot studies using cough monitoring as an 
endpoint (36, 37).  
 
With 15 patients per arm, this study will have 80% power with an alpha of 5% to detect an 
estimated 20% greater reduction in 24hr cough frequency compared with the placebo arm, 
assuming a log standard deviation of 0.60. A clinically relevant reduction in cough frequency of 
20% was established following a recent phase 3 studies of gefapixant in refractory chronic cough 
which showed a 20% reduction over placebo as significant (38). The data from this study will be 
used to estimate the sample size required for any future multi-centre studies.    
 
9.2. Statistical Analysis  
 
9.2.1. General Considerations, Assumptions, and Definitions 
 
This study will generate data of demographics, LCQ scores, modified Borg scores for 
sensations and cough, methacholine (PC20), blood eosinophils, sputum eosinophil, total and 
activated mature eosinophils in sputum and blood. These continuous variables will be presented 
and analysed as either mean (S.D), median (IQR) or geometric mean (geometric S.D).  
It is generally assumed that cough frequency data will not be normally distributed, and hence 
cough frequency data will be log transformed and shown as geometric mean (geometric S.D). 
Statistical significance will be set at p<0.05. 
 
For the purposes of analysis, the populations for analyses will be defined as: 
 
1. Full analysis set (FAS): consists of all subjects randomized to a treatment arm, 
who received at least one dose of investigational product irrespective of their 
protocol adherence and performed at least one period of 24-hr cough monitoring 
before and one after treatment. 
 
2. Per Protocol Set (PPS): consists of all patients in who did not have any major 
protocol deviations, and provided cough frequency recording at baseline, 4 weeks 
and 8 weeks after treatment.  

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
39
 
9.2.2. Primary Endpoint 
 
The primary endpoint in this study will be the change from baseline in 24-hour cough 
frequency (geometric mean) after 14 weeks of intervention over placebo (day 98, visit 8) 
adjusted for baseline cough frequency (day 13, visit 2). The primary efficacy endpoint will be 
analysed using a generalised estimating equation modelling (GEE) analysis including the 
baseline cough frequency as a co-variate. Both FAS and PPS populations will be analysed.   
 
9.2.3. Secondary Endpoint 
 
Comparison of cough frequency, LCQ, mBorg, sputum and blood eosinophilia, will be 
performed using the same statistical approach as for the primary outcome including data after 
week 8 and week 14 of intervention. The proportion of subjects with a reduction in cough 
frequency more than 30% in the mepolizumab and placebo groups will be analysed using a chi-
squared test.  
 
The effect of intervention on changes in inflammatory cells in blood and sputum and 
methacholine PC20 will be compared to baseline measurements in the mepolizumab/placebo 
group. This will be analysed using either an independent t-test or Mann-Whitney test depending 
on the normality of data.   
 
Changes in objective cough frequency will be correlated with changes in serum and sputum 
eosinophilia and all subjective patient reported outcomes.  
 
9.3. Missing, Unused, Spurious Data 
 
Spurious data will be re-analyzed with analysis of the primary efficacy endpoints using the 
primary efficacy analysis set, excluding any spurious data. If the results of this sensitivity 
analyses confirmed that these participants were influential to the primary endpoint point 
estimates and treatment effect estimates, the primary efficacy analysis set might be amended to 
exclude these participants and all endpoints evaluated in this revised analysis set for conclusion 
purposes.   
 
9.4. Statistical Plan Deviations 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
40
 
Any deviations from the original statistical plan would require a protocol amendment and 
would be described in the final study report. 
 
10. Data Handling and Recordkeeping 
 
10.1. Confidentiality and Security 
 
 
All data collected during the study will be stored on a secure database with limited access 
and password entry. A unique identifier made up of numbers and letters will be allocated and 
used on patient case notes and investigation results. Data will be collected and stored at 
McMaster University. All personal data collected during the study will be handled in accordance 
with the GCP code of practice for confidential patient information and the data protection act. 
Source data collected in Canada will be stored and archived in Canada according to local 
research standards policies and procedures. A database of anonymized data will be shared 
including anonymized 24-hour cough recordings with Professor Jacky Smith. The latter will be 
transferred using a secure password encrypted file transfer protocol (FTP) to a secure server at 
the University of Manchester and stored as per local SOP. 
 
10.2. Training 
 
All staff working on this study will have suitable qualifications, training and experience to 
carry out the procedures listed in section 5.6.4. A medical doctor will always be available during 
study visits should a participant become unwell and require medical attention. It will be ensured 
that all members of the research team are trained in local health and safety policies, emergency 
procedures and policies governing the confidentiality and security of the data collected during the 
study.  
 
10.3. Records Retention 
 
All research related documentation including the site file, case record forms etc will be kept 
with the Principal Investigator until all the data has been analysed. Local SOPS will apply for 
archiving in Canada. All study records will be stored for 25 years following study completed. Per 
local Manchester procedures all cough recordings will be stored electronically for 25 years on an 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
41
encrypted hard drive and archived along with paper documentation. A log will be made of all the 
documents that are being destroyed. 
 
11. Direct Access to Source Data/Documents 
 
Source documents are considered to be all information in original records and certified 
copies of original records of clinical findings, observations, data, or other activities in a clinical 
study necessary for the reconstruction and evaluation of the study. The investigator will provide 
direct access to source documents and/or source data in the facilitation of trial-related 
monitoring, audits, review by REB, and regulatory inspections. 
 
The investigator/institution will maintain adequate and accurate source documents and trial 
records that include all pertinent observations on each of the site’s trial participants. Source data 
will be attributable, legible, contemporaneous, original, accurate, and complete. Changes to 
source data will be traceable, not obscure the original entry, and be explained if necessary. 
 
The study will be monitored according to the Sponsor’s monitoring plan to ensure that it is 
conducted and documented properly according to the protocol, GCP, and all applicable 
regulatory requirements. Monitoring visits will be outlined in the study monitoring plan. The PI 
will assure she and adequate site personnel are available throughout the study to collaborate with 
clinical monitors. Clinical monitors must have direct access to source documentation in order to 
check the completeness, clarity, and consistency of the data recorded in the eCRFs for each 
participant. 
 
The investigator will make available to the clinical monitor all source documents and 
medical records necessary to review protocol adherence and eCRFs. In addition, the investigator 
will work closely with the clinical monitor and, as needed, provide them appropriate evidence 
that the study is being conducted in accordance with the protocol, applicable regulations, and 
GCP guidelines. 
 
12. Quality Control and Quality Assurance 
 
 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
42
On behalf of the Sponsor, the Investigators will perform obligations of the sponsor under 
GCP-ICH, including but not limited to being responsible for (i) overseeing the overall conduct 
and management of the study and handling of the study data at McMaster; (ii) the design of the 
study process and protocol; (iii) implementing and maintaining quality assurance and control to 
facilitate the overall study being conducted in compliance with the protocol.  
 
13. Regulatory  
 
13.1. Ethical Considerations 
 
We do not anticipate any major ethical issues with this study. All patients will be informed 
that testing for blood borne infections will be performed at screening as part of assessing 
eligibility of the study. All research methods employed in this study have been previously 
applied in both healthy volunteers, patients with chronic cough and asthma with no reports of 
serious adverse events. Mepolizumab is currently approved by Health Canada for use in patients 
with severe eosinophilic asthma. 
 
Patients who have been prescribed and currently taking amitriptyline, dextromethorphan, 
pregabalin, gabapentin or opioids for chronic cough, but have demonstrated no clinical benefit, 
would be withdrawn off those medication.  The patients would be eligible for the study after 
waiting at least 5 half-lives to clear the drug.  
 
The cough monitor is an audio recording device and will record all sound including 
conversations. It is possible that despite processing of the cough recording by customised 
software, some of the participant’s conversations are also captured in addition to their cough 
sounds. Prior to enrolment in the trial, this possibility will be explained to the subjects. Any 
conversations recorded would be treated with the usual standards of confidentiality as per GCP 
guidelines. Confidentiality would only be broken if it is in the best interest of the patient or 
members of the public, e.g. if a subject describes serious intent of harming themselves or others. 
The cough monitor also has a mute button to allow sensitive personal conversations to be muted.  
 
13.2. Research Ethics Board 
 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
43
The Investigator will provide the Research Ethics Board with all appropriate material, 
including the informed consent document.  The study will not be started until appropriate REB 
approval of the protocol, the informed consent and all recruiting materials is obtained.  
Appropriate reports on the progress of the study will be made to the Research Ethics Board by 
the Investigator in accordance with applicable institutional regulations. 
 
13.3. Ethical Conduct of the Study 
 
This study will be conducted in accordance with the protocol, Good Clinical Practice (GCP) 
according to International Conference on Harmonization (ICH) guidelines, and regulatory 
requirements for the participating institution.  The study will be conducted under a protocol 
reviewed by a Research Ethics Board; the study will be conducted by scientifically and 
medically qualified persons; the benefits of the study are in proportion to the risks; the rights and 
welfare of the subjects will be respected; the physicians conducting the study do not find the 
hazards outweigh the potential benefits; and each subject will give his or her informed consent 
without duress. 
 
13.4. Subject Information and Consent 
 
A properly executed, written, informed consent form, in compliance with GCP according to 
ICH guidelines will be submitted by the investigator to the Research Ethics Board for review and 
approval prior to the start of the study.  Before entering subjects into the study, a copy of the 
Research Ethics Board-approved informed consent will be reviewed with the potential 
participant and signed and dated.  The investigator will provide a copy of the signed informed 
consent form to each subject and will maintain a copy in the subject’s study file.  
 
13.5. Health Canada 
 
This study will be reviewed by Health Canada and must receive a No Objection Letter prior 
to commencement. The study will conform to all Health Canada regulations. 
 
13.6. Protocol Amendments 
 
Amendments to the protocol that entail corrections of typographical errors, clarifications of 
confusing wording, changes in study personnel, and minor modifications that have no effect on 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
44
the safety of participants or the conduct of the study will be classed as administrative 
amendments and will be submitted to the REB for information only. The investigator will ensure 
that acknowledgement is received and filed. Amendments that are classed as substantial 
amendments must be submitted to the appropriate regulatory authorities and the REBs for 
approval and will not be implemented at sites until such approvals are received other than in the 
case of an urgent safety measure. 
 
13.7. Protocol Deviations 
 
Protocol deviations and/or violations and the reasons they occurred will be included in the 
clinical study report. Reporting of protocol deviations to the REB and in accordance with 
applicable regulatory authority mandates is an investigator responsibility. All protocol deviations 
will be identified, evaluated, and closed before the respective database lock (final analysis) and 
will be described in the clinical study report. Protocol deviations incurred as a direct result of the 
COVID-19 pandemic should be specifically recorded as a “COVID-19” deviation so that they 
can be easily identified and incorporated into the clinical study report. 
 
14. Study Administration 
 
14.1. Organization and Participating Centre 
 
This is a single centre study based at McMaster University, Department of Medicine, 
Division of Respiratory Medicine, Cardio-Respiratory Research Facility, HSC 3U31, 1280 Main 
St. West, Hamilton, Ontario, Canada, L8S 4K1. 
 
14.2. Investigators 
 
All study visits and data collection will be conducted at McMaster University. 
McMaster University: 
Dr. Paul O’Byrne MB  
Dr. Imran Satia MD PhD 
Dr. Gail Gauvreau, PhD 
Dr. Roma Sehmi, PhD 
Dr. Kieran Killian, MB 
 
University of Manchester: 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
45
 
Dr. Jacky Smith, MD PhD 
 
Dr. Jacky Smith will be responsible for analysing and providing reports for the objective cough 
frequency endpoints. 
 
15. Financing  
 
15.1. Funding Source 
 
This study is funded by GSK Canada with an investigator-initiated grant to Dr. Paul O’Byrne 
and Dr. Imran Satia.  
 
16. Publication Policy and Disclosure of Data 
 
Both the use of data and the publication policy are detailed within the clinical study 
agreement. Intellectual property rights (and related matters) generated by the investigator and 
others performing the clinical study will be participant to the terms of a clinical study agreement 
that will be agreed between the institution and the Sponsor or their designee. With respect to 
such rights, the Sponsor or its designee will solely own all rights and interests in any materials, 
data, and intellectual property rights developed by investigators and others performing the 
clinical study described in this protocol, participant to the terms of any such agreement. In order 
to facilitate such ownership, investigators will be required to assign all such inventions either to 
their institution or directly to the Sponsor or its designee, as will be set forth in the clinical study 
agreement. 
 
The study will be registered on clinicaltrials.gov. We also aim to publish this study in a peer-
reviewed scientific journal and present at national and international meetings. 
 
 
 
 
 
 
 
 
 
 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
46
 
17. References 
 
1. 
Schappert SM, Burt CW. Ambulatory care visits to physician offices, hospital outpatient 
departments, and emergency departments: United States, 2001-02. Vital and Health Statistics 
Series 13, Data from the National Health Survey. 2006(159):1-66. 
2. 
Song WJ, Chang YS, Faruqi S, Kim JY, Kang MG, Kim S, et al. The global 
epidemiology of chronic cough in adults: a systematic review and meta-analysis. Eur Respir J. 
2015;45(5):1479-81. 
3. 
Irwin RS, Baumann MH, Bolser DC, Boulet L-P, Bra-man SS, Brightling CE, et al. 
Diagnosis and management of cough: ACCP evidence-based clinical practice guidelines. Chest-
Chicago-. 2006;129:24S. 
4. 
French CL, Irwin RS, Curley FJ, Krikorian CJ. Impact of chronic cough on quality of 
life. Archives of internal medicine. 1998;158(15):1657-61. 
5. 
Brightling CE, Ward R, Goh KL, Wardlaw AJ, Pavord ID. Eosinophilic bronchitis is an 
important cause of chronic cough. American journal of respiratory and critical care medicine. 
1999;160(2):406-10. 
6. 
Gibson P, Denburg J, Dolovich J, Ramsdale E, Hargreave F. Chronic cough: eosinophilic 
bronchitis without asthma. The Lancet. 1989;333(8651):1346-8. 
7. 
Carney IK, Gibson PG, Murree-Allen K, Saltos N, Olson LG, Hensley MJ. A systematic 
evaluation of mechanisms in chronic cough. American journal of respiratory and critical care 
medicine. 1997;156(1):211-6. 
8. 
Satia I, Watson R, Scime T, Dockry RJ, Sen S, Ford JW, et al. Allergen challenge 
increases capsaicin-evoked cough responses in patients with allergic asthma. J Allergy Clin 
Immunol. 2019;144(3):788-95 e1. 
9. 
Drake MG, Scott GD, Blum ED, Lebold KM, Nie Z, Lee JJ, et al. Eosinophils increase 
airway sensory nerve density in mice and in human asthma. Science translational medicine. 
2018;10(457):eaar8477. 
10. 
Cullinan P. Aetiological factors in persistent sputum production: a case-control study. J 
Epidemiol Community Health. 1993;47(1):27-31. 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
47
11. 
Ford AC, Forman D, Moayyedi P, Morice AH. Cough in the community: a cross 
sectional survey and the relationship to gastrointestinal symptoms. Thorax. 2006;61(11):975-9. 
12. 
French CL, Irwin RS, Curley FJ, Krikorian CJ. Impact of chronic cough on quality of 
life. Arch Intern Med. 1998;158(15):1657-61. 
13. 
Morice A, Kastelik JA, Thompson RH. Gender differences in airway behaviour. Thorax. 
2000;55(7):629. 
14. 
Hilton E, Marsden P, Thurston A, Kennedy S, Decalmer S, Smith JA. Clinical features of 
the urge-to-cough in patients with chronic cough. Respir Med. 2015;109(6):701-7. 
15. 
McGarvey L, McKeagney P, Polley L, MacMahon J, Costello RW. Are there clinical 
features of a sensitized cough reflex? Pulm Pharmacol Ther. 2009;22(2):59-64. 
16. 
McGarvey LP, Carton C, Gamble LA, Heaney LG, Shepherd R, Ennis M, et al. 
Prevalence of psychomorbidity among patients with chronic cough. Cough. 2006;2:4. 
17. 
Smith SM, Schroeder K, Fahey T. Over-the-counter (OTC) medications for acute cough 
in children and adults in community settings. Cochrane Database Syst Rev. 2014(11):CD001831. 
18. 
Morice AH, Kastelik JA. Cough. 1: Chronic cough in adults. Thorax. 2003;58(10):901-7. 
19. 
Irwin RS, Curley FJ, French CL. Chronic cough. The spectrum and frequency of causes, 
key components of the diagnostic evaluation, and outcome of specific therapy. Am Rev Respir 
Dis. 1990;141(3):640-7. 
20. 
Gibson PG, Dolovich J, Denburg J, Ramsdale EH, Hargreave FE. Chronic cough: 
eosinophilic bronchitis without asthma. Lancet. 1989;1(8651):1346-8. 
21. 
Ayik SÖ, BASOĜLU ÖK, ERDÍNÇ M, BOR S, Veral A, Bílgen C. Eosinophilic 
bronchitis as a cause of chronic cough. Respiratory medicine. 2003;97(6):695-701. 
22. 
Lai K, Chen R, Lin J, Huang K, Shen H, Kong L, et al. A prospective, multicenter survey 
on causes of chronic cough in China. Chest. 2013;143(3):613-20. 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
48
23. 
Cote A, Russell RJ, Boulet LP, Gibson PG, Lai K, Irwin RS, et al. Managing Chronic 
Cough due to Asthma and NAEB in Adults and Adolescents: CHEST Guideline and Expert 
Panel Report. Chest. 2020. 
24. 
Canning BJ, Chou YL. Cough sensors. I. Physiological and pharmacological properties 
of the afferent nerves regulating cough. Handbook of experimental pharmacology. 2009(187):23-
47. 
25. 
Sanderson CJ. Interleukin-5, eosinophils, and disease. Blood. 1992;79(12):3101-9. 
26. 
Lopez A, Sanderson C, Gamble J, Campbell H, Young I, Vadas M. Recombinant human 
interleukin 5 is a selective activator of human eosinophil function. Journal of Experimental 
Medicine. 1988;167(1):219-24. 
27. 
Clutterbuck EJ, Hirst E, Sanderson CJ. Human interleukin-5 (IL-5) regulates the 
production of eosinophils in human bone marrow cultures: comparison and interaction with IL-1, 
IL-3, IL-6, and GMCSF. 1989. 
28. 
Pouliquen IJ, Kornmann O, Barton SV, Price JA, Ortega HG. Characterization of the 
relationship between dose and blood eosinophil response following subcutaneous administration 
of mepolizumab. Int J Clin Pharmacol Ther. 2015;53(12):1015-27. 
29. 
Haldar P, Brightling CE, Hargadon B, Gupta S, Monteiro W, Sousa A, et al. 
Mepolizumab and exacerbations of refractory eosinophilic asthma. New England Journal of 
Medicine. 2009;360(10):973-84. 
30. 
Ortega HG, Liu MC, Pavord ID, Brusselle GG, FitzGerald JM, Chetta A, et al. 
Mepolizumab treatment in patients with severe eosinophilic asthma. New England Journal of 
Medicine. 2014;371(13):1198-207. 
31. 
Crapo RO, Casaburi R, Coates AL, Enright PL, Hankinson JL, Irvin CG, et al. Guidelines 
for methacholine and exercise challenge testing-1999. This official statement of the American 
Thoracic Society was adopted by the ATS Board of Directors, July 1999. Am J Respir Crit Care 
Med. 2000;161(1):309-29. 
32. 
Tashkin DP, Altose MD, Bleecker ER, Connett JE, Kanner RE, Lee WW, et al. The lung 
health study: airway responsiveness to inhaled methacholine in smokers with mild to moderate 
airflow limitation. The Lung Health Study Research Group. Am Rev Respir Dis. 1992;145(2 Pt 
1):301-10. 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
49
33. 
Vlachos-Mayer H, Leigh R, Sharon RF, Hussack P, Hargreave FE. Success and safety of 
sputum induction in the clinical setting. Eur Respir J. 2000;16(5):997-1000. 
34. 
Fahy JV, Wong H, Liu J, Boushey HA. Comparison of samples collected by sputum 
induction and bronchoscopy from asthmatic and healthy subjects. Am J Respir Crit Care Med. 
1995;152(1):53-8. 
35. 
Mulder A, Gauvreau GM, Watson RM, O'Byrne P M. Effect of inhaled leukotriene D4 
on airway eosinophilia and airway hyperresponsiveness in asthmatic subjects. Am J Respir Crit 
Care Med. 1999;159(5 Pt 1):1562-7. 
36. 
Smith J, Allman D, Badri H, Miller R, Morris J, Satia I, et al. The Neurokinin-1 Receptor 
Antagonist Orvepitant Is a Novel Antitussive Therapy for Chronic Refractory Cough: Results 
From a Phase 2 Pilot Study (VOLCANO-1). Chest. 2020;157(1):111-8. 
37. 
Ludbrook V, Hanrott K, Marks-Konczalik J, Kreindler J, Bird N, Hewens D, et al. S27 A 
placebo-controlled, double-blind, randomized, crossover study to assess the efficacy, safety and 
tolerability of TRPV4 inhibitor GSK2798745 in participants with chronic cough. BMJ 
Publishing Group Ltd; 2019. 
 
38. 
Muccino D, Morice A, Birring S, Dicpinigasitis P, Pavord I, Assaid C, Kleijn HJ, 
Hussain A, La Rosa C, McGarvey L, Smith J. Design and rationale of two phase 3 randomised 
controlled trials (COUGH-1 and COUGH-2) of gefapixant, a P2X3 receptor antagonist, in 
refractory or unexplained chronic cough. ERJ Open Research. 2020; 6(4): 00284-2020. 
 
 
 
 
 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
50
Appendix 1. Leicester Cough Questionnaire 
 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
51
Appendix 2. Modified Borg Scale 
 
The modified Borg Scale will assess your self-perceived frequency and intensity of your cough 
and associated sensations including urge to cough, throat itch, throat tickle, and throat irritation. 
Please use the scale to rate the severity of your cough sensations.  
 
0 or “Nothing at all” means no cough sensations. 
10 or “Maximal” means the most severe cough sensations you have experienced.  
 
Scale 
Cough 
Frequency 
Cough 
Intensity 
Urge to 
cough 
Throat 
itch 
Throat 
tickle 
Throat 
irritation 
0 - Nothing at all 
 
 
 
 
 
 
0.5 - Very, very slight 
(just noticeable) 
 
 
 
 
 
 
1 - Very slight 
 
 
 
 
 
 
2 - Slight 
 
 
 
 
 
 
3 - Moderate 
 
 
 
 
 
 
4 - Somewhat severe 
 
 
 
 
 
 
5 - Severe 
 
 
 
 
 
 
6 
 
 
 
 
 
 
7 - Very severe 
 
 
 
 
 
 
8 
 
 
 
 
 
 
9 - Very, very severe 
 
 
 
 
 
 
10 - Maximal 
 
 
 
 
 
 
 
 
 
 
 
 

MUCOSA Clinical Study Protocol 
Satia, O’Byrne, Gauvreau, Sehmi,  
Drug Substance Mepolizumab 
Killian, and Smith 
McMaster University 
Version 2.4-22JUNE2023 
52
Appendix 3. Cough Severity Visual Analogue Scale 
 
 
 
How severe has your cough been over the last week? 
 
Please place a single vertical line on the scale that best describes the severity of your cough over 
the past week (7 days).