The Effect of NAC on Lung Function and CT Mucus Score
Phase: PHASE4
Conditions: Asthma
Sponsor: University of California, San Francisco

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JOHN V. FAHY, MD, MSC
Clinical Research Protocol
THE EFFECT OF NAC ON LUNG FUNCTION AND CT MUCUS SCORE (ENACT)
Protocol Number:
18-26680
Version Date:
5/26/2021
Investigational 
Product:
n-acetylcysteine
Development 
Phase:
4
Sponsor:
John V. Fahy, MD, MSc
513 Parnassus Avenue, HSE 1307
San Francisco, Ca 94143-0130
Funding 
Organization:
National Institutes of Health
Principal 
Investigator:
Name: John V. Fahy, MD, MSc
Telephone: 415-476-9940
Fax: 415-476-5712
E-mail:John.Fahy@ucsf.edu
Medical Monitor:
Name: John V. Fahy, MD, MSc
Telephone: 415-476-9940
Fax: 415-476-5712
E-mail:John.Fahy@ucsf.edu
Approval:
, Professor
11/21/2018
PI or Sponsor Signature (Name and Title) 
Date
This confidential information about an investigational product is provided for the exclusive use of 
investigators of this product and is subject to recall at any time.  The information in this document 
may not be disclosed unless federal or state law or regulations require such disclosure.  Subject to the 
foregoing, this information may be disclosed only to those persons involved in the study who have a 
need to know, with the obligation not to further diseminate this information.  

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PROTOCOL AGREEMENT
I have read the protocol specified below. In my formal capacity as Investigator, my duties 
include ensuring the safety of the study participants enrolled under my supervision and 
providing the Airway Clinical Research Center Quality Assurance Committee and the 
UCSF Committee on Human Research with complete and timely information, as outlined 
in the protocol.  It is understood that all information pertaining to the study will be held 
strictly confidential and that this confidentiality requirement applies to all study staff at this 
site. Furthermore, on behalf of the study staff and myself, I agree to maintain the 
procedures required to carry out the study in accordance with accepted GCP principles and 
to abide by the terms of this protocol.
Protocol Number:  18-26680
Protocol Title: The Effect of NAC on Lung Function and CT Mucus Score
Protocol Date: 11/20/2018
11/21/2018
Investigator Signature 
Date
John V. Fahy, Professor of Medicine
Print Name and Title
Site #
N/A
Site Name
University of California, San Francisco
Address
513 Parnassus Avenue, HSE 1307
San Francisco, Ca 94143-0130
Phone Number
415-476-9940

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TABLE OF CONTENTS
1
BACKGROUND.........................................................................................................10
1.1
Overview of Clinical Studies............................................................................................10
1.2
Overview of Non-Clinical Studies ...................................................................................11
2
STUDY RATIONALE ...............................................................................................12
2.1
Risk / Benefit Assessment................................................................................................12
3
STUDY OBJECTIVES ..............................................................................................13
3.1
Primary Objective.............................................................................................................13
3.2
Secondary Objectives .......................................................................................................13
4
STUDY DESIGN ........................................................................................................13
4.1
Study Overview................................................................................................................13
5
CRITERIA FOR EVALUATION.............................................................................13
5.1
Primary Efficacy Endpoint...............................................................................................13
5.2
Secondary Efficacy Endpoints .........................................................................................14
5.3
Safety Evaluations............................................................................................................14
6
PARTICIPANT SELECTION..................................................................................15
6.1
Study Population ..............................................................................................................15
6.2
Inclusion Criteria..............................................................................................................15
6.3
Exclusion Criteria.............................................................................................................15
6.4
Concurrent Medications ...................................................................................................15
6.5
Allowed Medications and Treatments..............................................................................16
6.6
Prohibited Medications and Treatments...........................................................................16
7
STUDY TREATMENTS............................................................................................16
7.1
Method of Assigning Participants to Treatment Groups..................................................16
7.2
Blinding............................................................................................................................16
7.3
Formulation of Test and Control Products .......................................................................16
7.3.1
Formulation of Test Product......................................................................................................17
7.3.2
Packaging and Labeling ............................................................................................................17
7.4
Supply of Study Drug at the Site......................................................................................17
7.4.1
Dosage/Dosage Regimen...........................................................................................................17
7.4.2
Dispensing..................................................................................................................................17
7.4.3
Administration Instructions .......................................................................................................18
7.5
Supply of Study Drug at the Site......................................................................................19
7.5.1
Storage .......................................................................................................................................19
7.6
Study Drug Accountability...............................................................................................19
8
STUDY PROCEDURES AND GUIDELINES ........................................................19
8.1
Clinical Assessments........................................................................................................20
8.1.1
Concomitant Medications ..........................................................................................................20
8.1.2
Medication Withholding.............................................................................................................20
8.1.3
Food & Beverage Withholding ..................................................................................................21
8.1.4
Demographics............................................................................................................................21
8.1.5
Medical History .........................................................................................................................21
8.1.6
Physical Examination ................................................................................................................21
8.1.7
Vital Signs ..................................................................................................................................21

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8.1.8
Oximetry.....................................................................................................................................21
8.1.9
Spirometry..................................................................................................................................21
8.1.10
Post-Bronchodilator Reversibility/Maximal Reversibility....................................................22
8.1.11
Methacholine Challenge Testing...........................................................................................22
8.1.12
Sputum Induction ..................................................................................................................23
8.1.13
Point of Care Urine Pregnancy Test.....................................................................................23
8.1.14
CT Imaging of the Thorax.....................................................................................................24
8.1.15
Body Plethysmography..........................................................................................................24
8.1.16
Measurement of Fractional Exhaled Nitric Oxide................................................................24
8.1.17
Adverse Events ......................................................................................................................25
8.2
Clinical Laboratory Measurements ..................................................................................25
8.2.1
Hematology................................................................................................................................25
8.3
Research Laboratory Measurements ................................................................................25
8.3.1
Sputum Cell Count and Differential ..........................................................................................25
8.3.2
Sputum Cytokine Gene Expression Measurements....................................................................25
8.3.3
Sputum Rheology .......................................................................................................................25
9
EVALUATIONS BY VISIT ......................................................................................25
9.1
Visit 1 ...............................................................................................................................25
9.2
Visit 2a..............................................................................................................................26
9.3
Visit 2b **Optional ..........................................................................................................26
9.4
Visit 3 (Day 0)..................................................................................................................26
9.5
Visit 4 (Day 7)..................................................................................................................26
9.6
Visit 5 (Day 14)................................................................................................................27
9.7
Visit 6 (Day 21)................................................................................................................27
9.8
Visit 7 (Day 77)................................................................................................................27
9.9
Visit 8 (Day 84)................................................................................................................28
9.10
Visit 9 (Day 91)................................................................................................................28
9.11
Visit 10 (Day 98)..............................................................................................................28
9.12
Early Withdrawal Visit.....................................................................................................29
10
ADVERSE EXPERIENCE REPORTING AND DOCUMENTATION...........29
10.1
Adverse Events.................................................................................................................29
10.2
Serious Adverse Experiences (SAE)................................................................................30
10.2.1
Serious Adverse Experience Reporting.................................................................................31
10.3
Medical Monitoring..........................................................................................................31
11
DISCONTINUATION AND REPLACEMENT OF PARTICIPANTS ............31
11.1
Early Discontinuation of Study Drug...............................................................................31
11.2
Withdrawal of Participants from the Study......................................................................32
11.3
Replacement of Participants.............................................................................................32
12
PROTOCOL VIOLATIONS.................................................................................32
13
DATA SAFETY MONITORING..........................................................................32
14
STATISTICAL METHODS AND CONSIDERATIONS...................................32
14.1
Data Sets Analyzed...........................................................................................................33
14.2
Demographic and Baseline Characteristics......................................................................33
14.3
Analysis of Primary Endpoint ..........................................................................................33
14.4
Analysis of Secondary Endpoints.....................................................................................33
14.5
Interim Analysis ...............................................................................................................33
14.6
Sample Size ......................................................................................................................33

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15
DATA COLLECTION, RETENTION AND MONITORING...........................33
15.1
Data Collection Instruments.............................................................................................33
15.2
Data Management Procedures..........................................................................................34
15.3
Data Quality Control and Reporting.................................................................................34
15.4
Archival of Data ...............................................................................................................34
15.5
Availability and Retention of Investigational Records ....................................................34
15.6
Monitoring........................................................................................................................35
15.7
Participant Confidentiality................................................................................................35
16
ADMINISTRATIVE, ETHICAL, REGULATORY CONSIDERATIONS......35
16.1
Protocol Amendments ......................................................................................................35
16.2
Institutional Review Boards and Independent Ethics Committees ..................................35
16.3
Informed Consent Form ...................................................................................................36
16.4
Publications ......................................................................................................................36
16.5
Investigator Responsibilities ............................................................................................36

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LIST OF ABBREVIATIONS
AE
adverse event
CBC
Complete blood count
CFR
Code of Federal Regulations
CRF
case report form
DMC
Data Monitoring Committee
DSMB
Data Safety Monitoring Board
FDA
Food and Drug Administration
FEV1
forced expiratory volume over one second
FVC
forced vital capacity
GCP
Good Clinical Practice
HIPAA
Health Insurance Portability and Accountability Act of 1996
ICF
informed consent form
ICH
International Conference on Harmonisation
IEC
Independent Ethics Committee
IRB
Institutional Review Board
NAC
n-acetylcysteine 
PI
Principal Investigator
SAE
serious adverse experience

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PROTOCOL SYNOPSIS
TITLE
The Effect of NAC on Lung Function and CT Mucus Score
SPONSOR
John V. Fahy, MD, MSc
FUNDING 
ORGANIZATION
National Institutes of Health, Departmental funds, Division of 
Pulmonary and Critical Care Medicine, Department of Medicine, 
UCSF
RESEARCH SITES
University of California, San Francisco and University of California, 
Davis
RATIONALE
Mucus plugging of the airway is consistently found in fatal and near-
fatal asthma. The role of mucus as a cause of airflow obstruction in 
acute severe asthma suggests that mucus plays a role in the 
pathophysiology of airflow obstruction in chronic severe asthma as 
well. This role has been hard to prove, however, in large part because 
of difficulty in showing that mucus occludes the lumen in chronic 
severe disease. Using a novel approach of scoring mucus occlusion, we 
have used CT imaging to uncover that a majority of asthmatics in the 
NHLBI Severe Asthma Research Program (SARP) have at least one 
lung segment with a mucus plug and 27% have more than four lung 
segments with mucus plugs. 
Historically, studies of mucolytics, like n-acetylcystine (NAC), have 
not shown benefit in other obstructive lung diseases, like COPD. 
However, utilizing CT mucus scores as a biomarker, we believe that 
mucolytic treatment may prove useful for those with significant mucus 
impaction.
STUDY DESIGN
This is a multi-center, randomized, double-blind, placebo-controlled 
phase 4 study.
PRIMARY 
OBJECTIVE
The primary objective is to determine if inhaled NAC decreases mucus 
plugs and improves lung function in patients with asthma.
SECONDARY 
OBJECTIVES
The secondary objective is to determine the duration of benefit of 
inhaled NAC in asthma.
NUMBER OF 
PARTICIPANTS
36
PARTICIPANT 
SELECTION 
CRITERIA
Inclusion Criteria 
1. Male or female between the ages of 18 and 80 years of age at Visit 1 
2. Written informed consent obtained from subject and ability for 
subject to comply with the requirements of the study. 
3. Able to perform reproducible spirometry according to ATS criteria 
4. Physiological evidence of airflow obstruction (FEV1 bronchodilator 
reversibility of ≥ 12% or hyperreactivity to methacholine reflected by a 
methacholine PC20 ≤ 16 mg/mL) Historical methacholine data may be 
allowed. An exception will be made for enrollees whose FEV1 is < 
50% predicted (precluding methacholine challenge testing. If 

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bronchodilator reversibility is <12% in these participants, a diagnosis 
of asthma acceptable to the investigator is sufficient for inclusion in 
ENACT.
5. Clinical history of asthma per patient report or medical record 
6. Pre-bronchodilator FEV1 > 35% predicted 
7. Post-bronchodilator FEV1 > 40% but < 90% predicted. If the 
participant has past evidence of mucus impaction as described by a 
radiologist on a prior chest CT scan, then post-bronchodilator FEV1 
needs to be >40% but <95% predicted. 
8. Asthma requiring treatment with inhaled corticosteroids (ICS) for 3 
months or greater.  
9. CT mucus score ≥ 5 
10. Ability to tolerate study drug reflected by a post-treatment FEV1 ≥ 
80% of pre- treatment, pre-bronchodilator FEV1
Exclusion Criteria 
1. Pregnant, breastfeeding, or unwilling to practice birth control during 
participation in the study
2. Presence of a condition or abnormality that in the opinion of the 
Investigator would compromise the safety of the patient or the quality 
of the data
3. Smoking of tobacco or other recreational inhalants in last year 
and/or >10 pack-year smoking history 
4. Current participation in an investigational drug trial 
5. Uncontrolled asthma as evidenced by an asthma exacerbation in 6 
weeks prior to study participation or albuterol use greater than 8 puffs 
per day
6. Other chronic pulmonary disorders, including (but not limited to) 
cystic fibrosis, chronic obstructive pulmonary disease, chronic 
bronchitis, vocal cord dysfunction (that is the sole cause of respiratory 
symptoms and at the PI’s discretion), severe scoliosis or chest wall 
deformities that affect lung function, or congenital disorders of the 
lungs or airways 
7. Unwillingness to follow study procedures 
8. History of allergy or intolerance to study drug 
9. Any other criteria that places the subject at unnecessary risk 
according to the judgment of the Principal Investigator
TEST PRODUCT, 
DOSE, AND ROUTE 
OF 
ADMINISTRATION
10% NAC (3 ml) and 2.5 mg albuterol (0.5 ml)
Product will be administered every 8-12 hours (2 times per day) for 14 
days.  Medication will be administered via a portable nebulizer. 
 
CONTROL 
PRODUCT, DOSE 
AND ROUTE OF 
ADMINISTRATION
0.9% saline (3mL) and 2.5 mg albuterol (0.5ml)
Product will be administered every 8-12hours (2 times per day) for 14 
days.  Medication will be administered via a portable nebulizer. 

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DURATION OF 
PARTICIPATION 
AND DURATION OF 
STUDY
Participants will be enrolled in the study up to 178 days:
Screening:  up to 90 days
Treatment Period 1:  14 days 
Washout:  60 days
Treatment Period 2: 14 days
The total duration of the study is expected to be 24 months.  
Participant recruitment will happen on a rolling basis.  
CONCOMMITANT 
MEDICATIONS
Prohibited: 

thiols and thiol derivatives 

activated charcoal 

inhaled insulin
EFFICACY 
EVALUATIONS
PRIMARY ENDPOINT
The primary outcome is the % change in FEV1 from the start to the end 
of the treatment period (either placebo or 10% NAC).
SECONDARY 
ENDPOINTS
Secondary efficacy endpoints include: 

CT mucus score 

FVC 

PEF (AM and PM) 

Air trapping (RV/TLC ratio) 

FeNO 

Blood eosinophils
OTHER 
EVALUATIONS
Rheological properties of sputum.
SAFETY 
EVALUATIONS
Incidence of adverse events
PLANNED INTERIM 
ANALYSES 
No interim analysis is planned
Serious adverse events will be monitored by the ACRC data safety 
monitoring committee on an ongoing basis throughout the study.
STATISTICS
Primary Analysis Plan
The primary outcome is the % change in FEV1 from the start to the end 
of the treatment period (either placebo or 10% NAC). The first analysis 
will be to test the assumption of negligible carryover effects from study 
period 1 to period 2. We will compare the sum of the outcome values 
measured in the two periods for each participant across the 2 sequence 
groups (placebo-10% vs. 10%-placebo) using an unpaired t-test. After 
no or negligible carryover effect has been confirmed, we will test for 
the difference in treatment effects between placebo and 10% NAC 
using a paired t-test.
Rationale for Number 
of Participants
The primary goal of this study is to assess whether N-acetyl cysteine 
improves FEV1 after a 2-week treatment period in patients with asthma 
when compared to a two week treatment period of placebo. The study 
has a cross-over design which reduces the sample size.  With help from 
David Mauger, Ph.D., biostatistician at Penn State, who has access to 
2-week FEV1 data in NIH network trials and cohort studies in asthma 
that UCSF has participated in, we calculate a sample size of 36 

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patients.  This sample size is obtained when we factor in an effect size 
of 5% improvement in FEV1, a standard deviation for change in FEV1 
of 20%, a within patient correlation for repeated measures of FEV1 of 
0.9, and a power of 90%. 

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1
BACKGROUND
Mucus plugging of the airway is consistently found in fatal asthma2. Decades ago, Dunnill 
provided graphic descriptions in 20 cases of fatal asthma3 noting that "the cut surface of the 
lung showed a striking picture with numerous grey, glistening, mucous plugs scattered 
throughout the airway passages." He summarized that "pathologically, the outstanding 
feature of the asthmatic lung lies in the failure of clearance of the bronchial secretions." 
Others have confirmed these findings, and it is only a small minority of asthma deaths that 
are not associated with airway mucus impaction. 
In non-fatal or near-fatal asthma exacerbations segmental collapse of lung lobes due to 
luminal occlusion is common. Lavage of these cases yields abnormal mucus plugs in the 
form of airway casts4. The combination of airway narrowing from concentric smooth 
muscle contraction with luminal obstruction by mucus marks asthma as uniquely 
dangerous among airway diseases in its propensity for sudden and sometimes fatal 
exacerbations. The role of mucus as a cause of airflow obstruction in acute severe asthma 
suggests that mucus plays a role in the pathophysiology of airflow obstruction in chronic 
severe asthma as well. This role has been hard to prove, however, in large part because of 
difficulty in showing that mucus occludes the lumen in chronic severe disease. Lungs are 
available at autopsy to show mucus occlusion in fatal asthma, and it is notable that there is 
evidence of occlusion in asthmatics who die with asthma (rather than because of it)5. But 
the field has yet to be persuaded of a role 
for mucus in airway dysfunction in 
chronic asthma. 
1.1
Overview of Clinical Studies
Against this background, the preliminary 
data we show in Figs 1 and 2 are very 
important, because we show how CT lung 
images can reveal mucus plugs in chronic 
severe asthma and how these plugs are 
associated with lower lung function. 
Specifically, we use CT imaging to 
uncover that a majority (58%) of 
asthmatics in the NHLBI Severe Asthma 
Research Program (SARP) have at least 
one lung segment with a mucus plug and 
27% have more than four lung segments 
with mucus plugs. Notably, asthmatics 
with a high mucus scores achieve a post 
albuterol FEV1 > 80% much less 
frequently than asthmatics who have a 
zero mucus score (Fig 3). 
Examined another way, we find that all 
asthmatics with an FEV1 < 60% after 
albuterol treatment have abnormal mucus 
scores, whereas the majority of asthmatics 
Figure 1: Intraluminal mucus in CT lung images 
of asthmatics. Mucus plugs in CT scan images 
(white arrows) were defined as complete occlusion 
of an airway lumen by mucus and were identified as 
tubular structures in longitudinal section with 
branching (A & B) or without branching (C) or as 
rounded opacities in cross-section (D). The latter 
were traced cephalad or caudad on adjacent slices to 
confirm their continuity with unocculded bronchi 
(red arrow). 

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with an FEV1 >80% with albuterol treatment have zero or low mucus scores (Fig 3). These 
data clearly implicate mucus plugs in the pathogenesis of airflow obstruction in asthma. 
One reason why this role for mucus plugging has been underappreciated in chronic severe 
asthma is that mucus-related symptoms are both insensitive and non-specific indicators of 
mucus. This is well illustrated in the table, which presents data for the prevalence of 
mucus-related symptoms in asthmatics with different mucus score categories. None of the 
mucus-related symptoms were significantly different in the zero, low or high mucus 
subgroups, and it is clear that these symptoms have very limited utility to investigate the 
role of mucus in asthma or to identify asthmatics who might benefit from mucus-directed 
treatments. 
1.2
Overview of Non-Clinical Studies
To test the hypothesis that airway mucus in asthma has 
abnormal elasticity, we performed rheology on induced 
sputum from 40 asthmatic participants recruited to 
UCSF as part of the SARP. The majority of these 
asthmatic participants (65%) had severe asthma. We 
compared the elastic modulus (G’) of these participants 
to induced sputum G’ in 11 healthy controls. We found 
that the G’ in the asthmatic group was significantly 
higher than normal (Fig 4A). Notably, we found a 
strong inverse correlation between G’ and FEV1 % 
(Fig 4B). This finding suggests that stiff mucus in the 
airway of asthmatics could be a mechanism of mucus 
impaction of airways and airflow obstruction. It further 
suggests that decreasing mucus G’ could be a treatment 
Figure 2. A. The CT mucus segment score is usually 0 in health but many asthmatics enrolled in the 
NHLBI Severe Asthma Research Program have scores above 0 with some as high as 15-19. B. The 
frequency distribution of mucus score in asthma shows that 42% of patients have a score of 0 (zero mucus 
score); among the remaining 58% of asthmatics, the median mucus score was 3.5, and we classified score 
between 0.5 and 3.5 as “low” and above 4.0 as “high”.
Figure 3. Mucus scores in 
asthmatics with different FEV1 
values (post 6-8 puffs of albuterol). 
Note that all asthmatics with an 
FEV1 <60% have abnormal mucus 
scores. 

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strategy to improve airflow. 
To determine if the G’ of 
asthmatic sputum is a result of 
excessive mucin disulfide 
bridges (as it is in CF), we 
measured the G’ in a subgroup 
of 6 asthmatics before and 
after the addition of n-
Acetylcystine (NAC) 
(61mM). We found that NAC 
markedly decreased the G’ at 
both 2 minutes and 12 minute 
time-points after the addition 
of NAC (Fig 4A & B). This 
indicates that disulfide bonds 
are a mechanism of high 
sputum elasticity and a target for mucolysis in asthma, and it suggests thiol-based 
compounds as a rational mucolytic strategy.
2
STUDY RATIONALE
Because we have shown that the high elasticity of asthmatic mucus can be markedly 
decreased with NAC ex vivo (Fig 4), we propose here an in vivo study to treat asthmatics 
with NAC to improve their lung function. It is perhaps surprising that inhaled NAC has not 
been tested in a clinical trial in asthma, but a significant reason has been the uncertainty 
outlined above for the role of mucus in chronic disease. Another factor has been that 
clinical trials of NAC in COPD and cystic fibrosis have had not been consistently 
encouraging. However, these trials have not had a biomarker to select patients who might 
benefit and they have used orally administered NAC, which does not achieve detectable 
drug concentration in airway lining fluid6. Our proposal to test the efficacy of NAC in a 
specific patient subgroup identified by a biomarker (CT imaging) is timely and addresses a 
novel approach to asthma treatment. Although NAC is a suboptimal mucolytic, we are 
confident that high dose (10%) treatment will effectively lyse airway mucus to improve 
airflow and pave the way for later clinical trials of a thiol-saccharide.
2.1
Risk / Benefit Assessment
Risk: Inhaled n-acetylcysteine (NAC) is approved for the treatment of mucus associated 
airway disease, including asthma. The main side effect from inhaled n-acetylcysteine 
(NAC) is bronchospasm. We find that co-administering NAC and albuterol effectively 
prevents excessive bronchoconstriction in asthmatic patients. Specifically, in eight 
asthmatics that were given doses of 20% NAC as high as 3 mL together with 3 mL of 
albuterol, the largest FEV1 decline was 6%. 
Benefit: Mucus plugs cause airway obstruction and symptoms of dyspnea. The role of 
mucolytics in decreasing plugs and increasing FEV1 has not been well studied. Our 
preliminary data, utilizing CT imaging and a novel scoring system, can identify and target a 
Figure 4. A. Sputum in asthma has an increased elastic modulus 
(G’). B. The G’ of asthma sputum is significantly and inversely 
related to FEV1 (ex vivo data from 40 asthmatics and 11 healthy 
participants [red dots])

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subgroup of patients who may benefit from inhaled mucolytic treatment more so than the 
asthmatic population as a whole. 
To minimize risk, study participants will be administered the first two treatments under the 
supervision of the study team in the Airway Clinical Research Center and will only be 
eligible to remain in the study if their post-treatment FEV1s are greater than 80% of their 
pre-treatment, pre-bronchodilator FEV1.  
3
STUDY OBJECTIVES
3.1
Primary Objective
The primary objective is to determine if inhaled NAC decreases mucus plugs and improves 
lung function in patients with asthma. 
3.2
Secondary Objectives
The secondary objective is to determine the duration of benefit of inhaled NAC in asthma 
and identify characteristics of those subjects who benefit from mucolytic treatment. 
4
STUDY DESIGN
4.1
Study Overview
This is a multi-center, double-blind, randomized, 2 period crossover trial in 36 subjects 
with asthma who demonstrate mucus plugging on a screening CT lung scan. Screening data 
will be reviewed to determine participant eligibility.  Participants who meet all inclusion 
criteria will self-administer nebulized 10% NAC (3 mL) and 2.5 mg albuterol inhalation 
solution (0.5 mL) or 0.9% saline (3 mL) and 2.5 mg albuterol inhalation solution (0.5 mL) 
to be taken 2 times per day for 14 days.  Following an 8-week washout period, participants 
will be switched to the alternate group for 14 days of treatment. Participants will be 
assigned to the treatments in random order.  Evaluations will be taken at baseline, end of 
first treatment, start of second treatment period, and at the end of the second treatment 
period.
The following treatment regimens will be used:

Experimental treatment of 3.0 mL 10% NAC + 2.5mg/0.5 mL albuterol

Placebo treatment of 0.9% saline + 2.5mg/0.5 mL albuterol
Total duration of participation will be 16 weeks.  Total duration of the study is expected to 
be 2 years.
5
CRITERIA FOR EVALUATION
5.1
Primary Efficacy Endpoint
FEV1 will be the primary endpoint because it is the most robust measure of airflow 
obstruction in asthma. We will compare the post-treatment FEV1s to pre-treatment baseline 
values. We calculate that with a sample size of 36 we will have 90% power to detect an 

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effect size of 5% improvement in FEV1 and a within patient correlation for repeated 
measures of FEV1 of 0.9.  
5.2
Secondary Efficacy Endpoints
We intend to examine the effect of the treatment on CT mucus score, however, because the 
CT mucus score is a novel measurement, we do not have preliminary data to describe the 
natural history of mucus in the airway over time or with treatment. Therefore, for the 
purpose of this study, we intend to describe any changes we observe.
Other Secondary efficacy endpoints will include: 

FVC 

PEF (AM and PM) 

Air trapping (RV/TLC ratio) 

FeNO 

Blood eosinophils 
5.3
Safety Evaluations
All participants will have their first two doses of each treatment period administered in the 
clinic under the supervision of a study nurse or study clinician. Participants will receive 
instruction on nebulizer use utilizing a teach-back method to ensure comprehension. 
Participants who are unable to successfully teach back nebulizer setup or drug self-
administration will be excluded from continued participation.
Additionally, while acute anaphylactoid reactions have only been observed in the setting of 
IV administered NAC, each participant will be observed for the first two treatments, lasting 
approximately 6 hours, by a study nurse or study clinician.
All participants will be asked to complete a log of study drug administration and any 
subjective side effects. 
Additionally, participants will have access via pager to a study nurse or clinician 24 hours a 
day, 7 days a week. 
Interim safety evaluations will be done after 7 days of treatment during each treatment 
period.  Additional safety evaluations will also be done if anticipated adverse events exceed 
frequencies documented in the literature, unanticipated adverse events occur, or rare but 
serious adverse events occur. Definitions of these terms and details of our safety evaluation 
plan are described in section 14. 
6
PARTICIPANT SELECTION
6.1
Study Population
Participants with a diagnosis of asthma who meet the inclusion and exclusion criteria will 
be eligible for participation in this study.  
6.2
Inclusion Criteria
1. Male or female between the ages of 18 and 80 years of age at Visit 1 

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2. Written informed consent obtained from subject and ability for subject to comply 
with the requirements of the study. 
3. Able to perform reproducible spirometry according to ATS criteria 4. Physiological 
evidence of airflow obstruction (FEV1 bronchodilator reversibility of ≥ 12% or 
hyperreactivity to methacholine reflected by a methacholine PC20 ≤ 16 mg/mL) 
Historical methacholine data may be allowed. An exception will be made for 
enrollees whose FEV1 is < 50% predicted (precluding methacholine challenge 
testing. If bronchodilator reversibility is <12% in these participants, a diagnosis of 
asthma acceptable to the investigator is sufficient for inclusion in ENACT.
4. Clinical history of asthma per patient report or medical record 
5. Pre-bronchodilator FEV1 > 35% predicted 
6. Post-bronchodilator FEV1 > 40% but < 90% predicted. If the participant has past 
evidence of mucus impaction as described by a radiologist on a prior chest CT scan, 
then post-bronchodilator FEV1 needs to be >40% but <95% predicted. 
7. Asthma requiring treatment with inhaled corticosteroids (ICS) for 3 months or 
greater. 
8. CT mucus score ≥ 5 
9. Ability to tolerate study drug reflected by a post-treatment FEV1 ≥ 80% of pre- 
treatment, pre-bronchodilator FEV1
6.3
Exclusion Criteria
1. Pregnant, breastfeeding, or unwilling to practice birth control during participation in 
the study. 
2. Presence of a condition or abnormality that in the opinion of the Investigator would 
compromise the safety of the patient or the quality of the data. 
3. Smoking of tobacco or other recreational inhalants in last year and/or >10 pack-year 
smoking history 
4. Current participation in an investigational drug trial 
5. Uncontrolled asthma as evidenced by an asthma exacerbation in 6 weeks prior to 
study participation or albuterol use greater than 8 puffs per day
6. Other chronic pulmonary disorders, including (but not limited to) cystic fibrosis, 
chronic obstructive pulmonary disease, chronic bronchitis, vocal cord dysfunction 
(that is the sole cause of respiratory symptoms and at the PI’s discretion), severe 
scoliosis or chest wall deformities that affect lung function, or congenital disorders 
of the lungs or airways 
7. Unwillingness to follow study procedures 
8. History of allergy or intolerance to study drug 
9. Any other criteria that places the subject at unnecessary risk according to the 
judgment of the Principal Investigator
6.4
Concurrent Medications
All participants should be maintained on the same medications throughout the entire study 
period, as medically feasible, with no introduction of new chronic therapies.

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6.5
Allowed Medications and Treatments
Standard therapy for asthma is allowed except for treatments noted in the exclusion criteria 
described above and as noted in the prohibited medications section below.  
6.6
Prohibited Medications and Treatments
The following medications are prohibited during the study and administration will be 
considered a protocol violation. 

Thiols and thiol derivatives 

Activated charcoal 

Inhaled insulin
7
STUDY TREATMENTS
7.1
Method of Assigning Participants to Treatment Groups
Up to 36 eligible patients will be randomly assigned to receive either the experimental 
treatment (10% NAC) or the placebo treatment (0.9% saline) during period 1 in a 1:1 ratio 
using a SAS-based computer-generated randomization scheme accessed by the 
investigational pharmacist.  The UCSF investigational pharmacist will complete a 
randomization worksheet and log the group assignment for subjects enrolled at both UCSF 
and UC Davis. The UCSF investigational pharmacist will contact the UC Davis pharmacist 
by email or phone to inform them of the randomization. The randomization log will be 
shared with investigators upon study completion or in the event of a serious safety concern. 
7.2
Blinding
Due to the objectives of the study, the identity of experimental and placebo treatments will 
not be known to investigators, research staff, or patients.  The following study procedures 
will be in place to ensure double-blind administration of study treatments.  
Access to the randomization code will be strictly controlled.  
Packaging and labeling of experimental and placebo treatments will be identical to 
maintain the blind. 
The study blind will be broken on completion of the clinical study and after the study 
database has been locked.  
During the study, the blind may be broken only in emergencies when knowledge of the 
patient’s treatment group is necessary for further patient management. When possible, the 
Investigator should discuss the emergency with a Quality Assurance officer and a 
representative from the Committee on Human Research prior to unblinding.  Should 
unblinding become necessary the Investigator will contact the investigational pharmacist 
directly.  
7.3
Formulation of Test and Control Products
NAC (trade name: Mucomyst) is manufactured by American Regent. The active drug 
studied here is 10% NAC. It will be delivered via nebulizer. 

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7.3.1
Formulation of Test Product
10% NAC is an existing formulation of Mucomyst (Mucomyst-20), manufactured by 
American Regent, for aerosol administration in the management of patients with chronic 
bronchopulmonary disease. 10% NAC is a colorless solution that requires no 
reconstitution. 
Albuterol sulfate inhalation solution is an existing formulation of Proventil Nebules, 
manufactured by Nephron Pharmaceuticals Corporation for oral inhalation in the 
management of patients with bronchospasm. Albuterol sulfate inhalation solution is a clear, 
colorless solution. 
Table 1: Formulation and Measured pH of 10% NAC, control product and albuterol
10% NAC
0.9% Saline
Albuterol
Active Ingredient, 
mg/mL
Acetylcysteine
100mg/mL
Albuterol sulfate  
2.5 mg/0.5mL
Other ingredient, 
mg/mL
Edetate disodium, 
sodium hydroxide, 
purified water
Sodium chloride
Purified water
Water, sodium 
chloride, sulfuric 
acid
pH
7
5.7
3-5
7.3.2
Packaging and Labeling
Subjects will receive a total of 14 syringes of study drug or placebo and 14-unit dose 
containers of albuterol (plus 2 extras in the event of breakage) for each treatment period. 
Each kit with syringe of study drug or placebo and the albuterol ampule will be labeled 
with the required FDA warning statement, the study ID, protocol number, the name of the 
sponsors, and directions for patient use and storage.  
7.4
Supply of Study Drug at the Site
Study drug will be supplied to both sites by Mariner Advanced Pharmacy Corp (MAPRx).  
MAPRx is a professional 503(a) patient-centered compounding pharmacy which prepares 
sterile and nonsterile drug preparations compliant with United States Pharmacopeia 
standards and the California State Board of Pharmacy.
The study medication will be supplied by MAPRx and delivered as needed per 
prescription. MAPRx can guarantee medication delivery to the study site within 1-2 
business days of submitting a prescription via MAPRx’s secured dashboard webportal. 
7.4.1
Dosage/Dosage Regimen
During each treatment period participants will nebulize one syringe of study drug and one 
unit dose container of albuterol using a portable nebulizer. Participants will be instructed to 
take two doses per day, spaced at approximately 8-12 hour intervals. No adjustments will 
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7.4.2
Dispensing
Study medication will be dispensed by either, the study coordinator, study nurse or 
physician and only after observation of the administration of the first two doses of each 
treatment period. 
7.4.3
Administration Instructions 
Charge Check
1. Wash hands prior to preparing each treatment. 
2. Use a clean nebulizer. 
3. Check the battery level by pressing the on/off button on the handset
a.
If the LED is SOLID GREEN the battery is charged
b. If the LED is SOLID AMBER, there is enough charge for at least one more 
treatment
*Please charge your nebulizer after your treatment 
c.
If the LED FLASHES AMBER and then switches off there is not enough 
charge to take a treatment
*Please charge your nebulizer before treatment
d. If the LED does not illuminate, please refer to the troubleshooting sections of 
the manual and call the study coordinator 
Nebulizer Assembly
1. Empty the contents of one-unit dose container labeled “albuterol” into the 
medication chamber with the green lid
2. Empty the contents of one syringe into the medication chamber
3. Close the lid to the medication chamber 
Treatment
1. Hold the handset in your hand and place the mouthpiece between your teeth with 
your lips sealed around it. 
2. Press the on/off button on the handset to switch the nebulizer on and begin 
nebulization and breathe normally through your mouth
3. Ensure aerosol is coming out of the mouthpiece assembly
4. Keep the nebulizer in an upright position during the course of the treatment. This 
prevents spilling and promotes nebulization
5. If you need to take a rest, press the on/off button to stop your treatment.  To 
continue your treatment press the on/off button again
6. Your treatment is finished when the nebulizer beeps and the LED flashes.  The 
device will turn off automatically
7. Check the medication chamber for residual medication.  If there are more than a 
few drops remaining, press the on/off button again to continue your treatment
After each use

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1. Press the mouthpiece assembly release button to separate the mouthpiece assembly 
from the handset. 
2. Rinse the mouthpiece assembly thoroughly under running tap water
3. Shake off excess water and allow to air dry fully before storing
Daily cleaning
1. Once per day, wash the mouthpiece assembly by hand in a bowl of warm soapy 
water (liquid dish soap) for 2 minutes
2. Rinse the mouthpiece assembly thoroughly under running tap water
3. Shake off excess water and allow to air dry fully before storing
Weekly disinfection
1. Prior to disinfection, ensure all parts are visibly clean and free from dirt/debris
2. Ensure the medication chamber lid is open and boil the mouthpiece assembly in 
water deep enough to prevent mouthpiece from touching the bottom for 10 minutes
3. Shake off excess water and allow to air dry fully before storing
7.5
Supply of Study Drug at the Site
Study drug supply will be maintained by MAPRx and will be supplied on a per participant 
basis. 7-day study drug supplies will be delivered to the clinical site within 48 hours of 
study visit corresponding to the start of week one of the treatment period and week two of 
the treatment period. 
7.5.1
Storage
Study drug should will be shipped and stored by the study site at refrigeration temperature, 
2 to 8ºC (36 to 46ºF). If the temperature of study drug storage in the clinic/pharmacy 
exceeds or falls below this range, this should be reported to the Sponsor or designee and 
captured as a deviation. Participants will be instructed to store the medication in original 
packaging in the refrigerator according to the instructions outlined on the Drug 
Administration Instructions.
7.6
Study Drug Accountability
An accurate and current accounting of the dispensing and return of study drug for each 
participant will be maintained on an ongoing basis by a member of the study site staff.  
Measures of Treatment Compliance:
Participants will be asked to keep a patient diary noting the day and date they take their 
study drug, whether they cotreat with albuterol and any adverse events. They will be asked 
to bring their patient diary to each study visit along with all used and unused study drug 
containers. After the first 7 days of treatment, subjects will be asked to return to the 
research center for a follow-up visit to measure adherence and to obtain the last 7 days of 
study drug.  If the subject’s adherence is less than 70%, during the first treatment period 
subjects will be terminated and will not receive any additional intervention or follow-up.  

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8
STUDY PROCEDURES AND GUIDELINES
A Schedule of Events representing the required testing procedures to be performed for the 
duration of the study is diagrammed in Appendix A.
Prior to conducting any study-related activities, written informed consent and the Health 
Insurance Portability and Accountability Act (HIPAA) authorization must be signed and 
dated by the participant.  
8.1
Clinical Assessments
8.1.1
Concomitant Medications
All concomitant medication and concurrent therapies will be documented at 
Baseline/Screening and at early termination when applicable.  Dose, route, unit frequency 
of administration, and indication for administration and dates of medication will be 
captured.
8.1.2
Medication Withholding
Bronchodilator reversibility will be used to establish eligibility at Visit 2a and will also be 
performed at visits 3-10. Since some asthma medications can blunt the response to 
bronchodilators, we may ask that participants withhold these medications according to the 
guidance provided in Table 2. 
Table 2. Medication Withholding Parameters
Medication
Withholding 
period
Leukotriene modifiers
24h
Ultra-long-acting bronchodilators (indacaterol)
24h
Long-acting muscarinic antagonists (tiotropium, glycopyrronium, 
umeclidinium)
24h
Long-acting muscarinic antagonists (aclidinium)
12h
Long-acting beta-agonists
12h
Theophylline
12h
Short-acting anticholinergic
6h
Short-acting beta-agonists
4h
Participants will be evaluated at visit 1, without any medication holds, to establish the 
safety of withholding asthma medications. If a study clinician feels the participant is not 
clinically stable enough to withhold medications, they may shorten the guidance (with 
appropriate documentation on the Visit 1 CRF Physician Attestation section) or they may 
excuse the participant from some or all of the medication withholds.  

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Participants are reminded of these medication holds by phone or email 24 hours prior to 
their medication withholding visits and instructed to resume all medications should 
symptoms develop in the period prior to the visit. 
Associated risks of medication withholding include a worsening of asthma control or 
asthma exacerbation. To mitigate these risks, participants are given clear instruction to 
resume asthma medications if symptoms arise. 
8.1.3
Food & Beverage Withholding
Participants are asked to withhold eating for our hour prior to sputum induction (visits 2, 6, 
7 and 10) because recently digested food can contaminate sputum samples. Participants are 
also asked to withhold caffeine and alcohol containing products for 6 hours prior to all 
study visits as these substances can influence lung function values. 
8.1.4
Demographics 
Demographic information (date of birth, gender, race) will be recorded at Screening.
8.1.5
Medical History 
Relevant medical history, including history of current disease, other pertinent respiratory 
history, and information regarding underlying diseases will be recorded at Screening.
Associated risks include discomfort evoked with some of the questions asked. To minimize 
risk, participants will be informed that they can defer answering any questions that make 
them feel uncomfortable. 
8.1.6
Physical Examination
A complete physical examination will be performed by either the investigator or a study 
clinician (MD, NP, RN, and PA) at visit 1. New abnormal physical exam findings must be 
documented and will be followed by a physician or other qualified staff at the next 
scheduled visit. Abbreviated physical exams may be performed as needed at visits 2-10.         
8.1.7
Vital Signs
Body temperature, blood pressure, pulse, and respirations will be performed after resting 
for 5 minutes at all study visits. 
8.1.8
Oximetry
Oximetry will be measured on room air with the participant at rest at all study visits.
8.1.9
Spirometry
Spirometry will be performed at visits 1-10 in accordance with the current American 
Thoracic Society recommendations for the performance and interpretation of tests. 
Associated risks include the following:

Likely (>10%)
·
Shortness of breath or cough during the six-second exhalation part.

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
Less Likely (<5%)
·
Wheezing and chest tightness.

Rare but serious (<1%)
·
Syncope
In an effort to minimize risk to participants will be seated during the procedure to reduce 
any injury should a participant become dizzy and fall. Coordinators will have albuterol 
available to administer to participants who develop wheeze or shortness of breath following 
spirometry.
8.1.10 Post-Bronchodilator Reversibility/Maximal Reversibility
Spirometry will be repeated 15 minutes following the administration of four to eight puffs 
of albuterol to assess bronchodilator reversibility. Maximal bronchodilation will be 
performed at Visit 2a. Post-bronchodilator reversibility will be performed at Visits 3-10. 
Associated risks include the following:

Likely (>10%): Transient tachycardia, tremor, feeling nervous, rhinitis, pharyngitis, 
and nausea 

Less Likely (<5%): Headache, cough, upper respiratory infection

Rare but serious (<1%): Chest pain, atrial fibrillation, hypertension, hypotension, 
diabetic ketoacidosis, hyperglycemia, hypersensitivity reactions, paradoxical 
bronchospasm
Given that the study population is made up of individuals with moderate-to-severe asthma, 
and that albuterol is a standard of care treatment for asthma, it is unlikely that participants 
will experience any of the side effects described above. However, if a potential participant 
describes previous sensitivity or side effects to treatment with albuterol, they will be 
excluded from participation for safety. Furthermore, albuterol will only be administered 
after a physician-administered history and physical, to ensure that it is okay for the 
participant to receive albuterol. 
8.1.11 Methacholine Challenge Testing
Methacholine challenge testing will be done according to the steps laid out in the UCSF 
Airway Clinical Research Center Methacholine Challenge Test Manual of Procedures or 
the University of California, Davis Pulmonary Services Laboratory standard protocol. Only 
participants that are unable to achieve 12% improvement in FEV1% following 
administration of 4 puffs of albuterol and who have a baseline FEV1 >50% predicted will 
undergo methacholine challenge testing. 
Associated risks include the following: 

Likely (>20%)
·
Shortness of breath.

Less Likely (< 20%)
·
Wheezing, tightness, or cough.

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
Rare but serious (< 1%)
·
Rarely, patients may have severe bronchoconstriction during or following 
methacholine challenge.
Additionally, methacholine has been shown to increase tone of the uterus, which could lead 
to preterm labor, in pregnant laboratory animals; there are no human studies to verify this 
effect during human pregnancy. However, because of this, methacholine has been placed in 
FDA category C, meaning that exposure during pregnancy should be avoided. As such, 
pregnant women or women of reproductive age who are unwilling to practice pregnancy 
prevention strategies will be excluded from participation.
In an effort to minimize risk to participants, only those participants with a pre-diluent 
FEV1 of >50% predicted will undergo the methacholine testing, and only in the instance 
that they are not able to show 12% or greater improvement in FEV1 following 
bronchodilator administration. A study physician will be available during the challenge. 
Participants will not be discharged until their FEV1 is within 10% of their prediluent 
FEV1. Medications and personnel will be available to manage and treat 
bronchoconstriction.
8.1.12 Sputum Induction 
A 12-minute sputum induction using 3% hypertonic saline will be performed at visits 2, 6, 
7 and 10. The procedure will be carried out according to the UCSF Airway Clinical 
Research Center Sputum Induction Manual of Procedures. The sputum induction procedure 
will only be performed at the UCSF site.  
Associated risks include the following:

Likely (>25%)
·
Salty after taste in the mouth, coughing, or a feeling of needing to swallow.

Less Likely (<5%)
·
Sore throat, shortness of breath, wheezing, chest tightness, light-headedness, 
nausea, or headache.
·
Worsening of lung function.

Rare but serious (<1%)
·
Some patients have had a severe asthma attack or a reaction to the salty 
water that they breathe in.
In an effort to minimize risk to participants, bronchodilator treatment will be available if 
sputum induction induces a worsening of asthma symptoms. The following safety 
procedures will be followed for the sputum induction procedure; only participants with a 
post-bronchodilator FEV1 of >50% predicted will undergo sputum induction, a physician 
will be available during the induction; study staff will calculate and record the peak flow 
and FEV1 value that equals both a 10% and 20% fall in lung function based upon the 
recorded post-bronchodilator peak flow and FEV1 values and participants will not be 
discharged until their FEV1 is within 10% of their post-bronchodilator FEV1.

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8.1.13 Point of Care Urine Pregnancy Test
A point of care urine pregnancy test will be obtained from female participants who are of 
childbearing potential prior to their participation in the study and routinely throughout their 
participation (see Appendix A). 
8.1.14 CT Imaging of the Thorax
A single inspiratory low dose CT scan of the thorax using a model based iterative 
reconstruction (MBIR) approach will be taken at visits 3, 6, 7, and 10. 
The risks associated with CT scanning are that of the additional amount of radiation 
exposure. At the UCSF, the additional amount of radiation that each participant will 
receive as a result of participating in this study will be approximately 5 mSv, which is 
slightly greater than the yearly natural background of radiation in the US, which is 3mSv. 
This amount of radiation may involve a low risk of cancer. A participant should not 
participate in this study if she is pregnant or breastfeeding.
Additional risks are associated with the uncovering abnormal findings. There is a risk of 
possible detection of an abnormality in the lung which, after testing or treatment, is found 
not to be disease-causing. This includes possible misdiagnosis of lung cancer. Such 
findings may result in unnecessary anxiety for the participant, and increase his or her 
chance that an outpatient physician may believe that the abnormality is lung cancer and 
order further testing. This testing could include additional CT scans with additional 
radiation exposure, other types of scans to determine if the abnormalities are rapidly 
growing, a needle biopsy (taking a sample of the abnormality with a needle) or a lung 
biopsy which requires surgery. Whether these additional studies would be performed would 
be a decision that the participant would make with his/her regular physician.
In an effort to minimize risk to participants, scans will be read by radiologists that have 
expertise in interpreting findings of chest CTs. If there are any abnormalities, other than 
those that are usually found in asthmatic patients, observed by the clinical center 
radiologists, these will be reported to the principal investigator, who will in turn 
communicate these findings to the participant. The most likely abnormal result will be the 
identification of a spot on the lung that might be cancer.
8.1.15 Body Plethysmography
Body plethysmography will be done to determine functional residual capacity (FRC), 
residual volume (RV), total lung capacity (TLC), and slow vital capacity (SVC) at Visit 4, 
6, 8 and 10. Plethysmography will be done with bronchodilation. If bronchodilation 
procedures are done, participants will follow the medication hold times as described in 
Section 9.1.2. In an effort to minimize risk to participants, patients with severe 
claustrophobia, inability to sit upright in a chamber, inability to perform the panting 
maneuver, inability to perform maximal inspiratory and expiratory efforts, and known 
perforated tympanic membrane without a snug-fitting earplug will be excluded from 
participation in the study.

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8.1.16 Measurement of Fractional Exhaled Nitric Oxide
Fractional exhaled nitric oxide measurement test will be performed at Visits 3-10. Subjects 
will inhale a full breath of air and then exhale it slowly through a mouthpiece while a 
device measures the concentration of nitric oxide in the air exhaled. Nitric oxide is a gas 
normally present in the air exhaled from the lungs.
8.1.17 Adverse Events
Information regarding occurrence of adverse events will be captured throughout the study. 
Duration (start and stop dates and times), severity/grade, outcome, treatment and relation to 
study drug will be recorded on the case report form (CRF).
8.2
Clinical Laboratory Measurements 
8.2.1
Hematology
UCSF: Up to 100 mL (about 7 tablespoons) of blood will be obtained by standard 
venipuncture, for the collection of DNA, plasma, serum, and complete blood count with 
differential (CBC-D).  Blood collection for DNA will be obtained at visit 3 and blood 
collection for plasma, serum and CBC-D will be collected at visits 3, 6, 7 and 10. 
UC Davis: Up to 15 mL (about 1 tablespoon) of blood will be obtained by standard 
venipuncture for the collection of complete blood count with differential (CBC-D).  Blood 
collection for CBC-D will be collected at visits 3, 6, 7, and 10. 
Risks associated with hematology include the following risks associated with venipuncture:

Lightheadedness or nausea while having blood drawn

Bruising at the site where the needle enters the skin and a remote risk of infection
In an effort to minimize risk to participants, aseptic technique will be used and pressure 
applied to site to prevent infection/bruising. Participants who have previously identified 
that they experience lightheadedness during blood draws will have blood drawn while lying 
supine on an exam room table. 
8.3
Research Laboratory Measurements 
Induced sputum will be collected at visits 2, 6, 7, and 10.  
8.3.1
Sputum Cell Count and Differential
Sputum for determination of total and differential cell counts will be collected at visits 2, 6, 
7 and 10. Specimens will be collected and processed according to the UCSF Airway 
Clinical Research Center Sputum Induction Manual of Procedures (Appendix C).  
8.3.2
Sputum Cytokine Gene Expression Measurements
Sputum for determination of RNA gene expression of a number of airway-specific genes 
will be collected at visits 2. Specimens will be collected and processed according to the 
UCSF Airway Clinical Research Center Sputum Induction Manual of Procedures.

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8.3.3
Sputum Rheology
Sputum for the determination of rheological properties will be collected at visits 2, 6, 7, 
and 10. The rheological measurements may be made using a portion of the sample 
collected at this time. Sputum will only be collected for rheology at the UCSF site.  
9
EVALUATIONS BY VISIT
9.1
Visit 1 
1.
Review the study with the participant and obtain written informed consent and 
HIPAA authorization.
2.
Assign the participant a unique screening number.
3.
Record demographics data.
4.
Record medical history, including history of asthma, diagnosis date, and asthma-
related healthcare utilization & exacerbation frequency. 
5.
Record concomitant medications.
6.
Perform a complete physical examination.
7.
Perform and record vital signs.
8.
Perform and record oximetry.
9.
Perform and record urine pregnancy test. 
10.
Perform and record spirometry.
11.
Schedule participant for Visit 2.
9.2
Visit 2a
1.
Review and record changes to concomitant medications.
2.
Perform and record vital signs.
3.
Perform and record oximetry.
4.
Perform and record urine pregnancy test. 
5.
Perform and record spirometry.
6.
Perform maximum reversibility and record post-bronchodilator spirometry.
7.
If FEV1 bronchodilator reversibility of ≥ 12% collect induced sputum and schedule 
for Visit 3.
8.
If FEV1 bronchodilator reversibility of ≤12% schedule participant for Visit 2b.
9.3
Visit 2b **Optional
1.      Perform and record vital signs.
2.    Perform and record oximetry.
3.
Perform and record urine pregnancy test. 
4.
Perform and record spirometry.
5.
Perform methacholine challenge testing. 
6.
Collect induced sputum.
7.
Schedule participant for Visit 3. 
9.4
Visit 3 (Day 0)
1.
Review and record changes to concomitant medications.
2.
Perform and record vital signs.

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3.
Perform and record oximetry.
4.
Perform and record urine pregnancy test. 
5.
Perform and record fractional exhaled nitric oxide (FeNO) measurement.
6.
Perform and record spirometry.
7.
Perform and record post-bronchodilator spirometry. 
8.
Obtain a CT scan of the thorax.
9.
Collect blood for clinical laboratory tests.
10.
Schedule participant for Visit 4 within 7 days.
9.5
Visit 4 (Day 7)
1.
Review and record changes to concomitant medications.
2.
Perform and record vital signs.
3.
Perform and record oximetry.
4.
Perform and record urine pregnancy test
5.
Perform and record fractional exhaled nitric oxide (FeNO) measurement.
6.
Perform and record spirometry.
7.
Perform and record post-bronchodilator reversibility. 
8.
Perform and record plethysmography with bronchodilation.
9.
Randomize
10.
Provide education on use of personal nebulizer and administration of study 
medication. 
11.
Administer first two treatments of study drug treatment, spaced 4-6 hours. FEV1 
measurements should be taken before and after each treatment.
12.
Dispense study drug and initiate study diary if subject’s post-treatment FEV1 is 
greater than 80% of pre-treatment FEV1.
13.
Schedule participant for phone follow-up in 3-5 days and visit 5 in 7 days.
9.6
Phone follow-up (Day 9, 10, or 11)
1. Administer questionnaire to monitor for treatment related side effects. 
9.7
Visit 5 (Day 14)
1.
Review and record any adverse experiences and/or review participant diary for 
adverse experiences and exclusionary medication use
2.
Review and record concomitant medications.
3.
Perform abbreviated physical examination.
4.
Perform and record vital signs.
5.
Perform and record oximetry.
6.
Perform and record urine pregnancy test
7.
Perform and record spirometry.
8.
Perform and record post-bronchodilator spirometry.
9.
Collect any unused study drug. 
10.
Review diary card. 
11.
If subject’s adherence is greater than 70%, dispense 7 days of study drug. 
12.
Schedule participant for Visit 6 in 7 days. 

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9.8
Visit 6 (Day 21)
1.     Review and record changes to concomitant medications.
2.     Perform and record vital signs.
3.     Perform and record oximetry.
4.     Perform and record urine pregnancy test
5.
Perform and record fractional exhaled nitric oxide (FeNO) measurement.
6.
Perform and record spirometry.
7.
Perform and record post-bronchodilator reversibility. 
8.
Perform and record plethysmography with bronchodilation.
9.
Obtain a CT scan of the thorax
10.
Collect induced sputum sample
11.
Collect blood for clinical laboratory tests.
12.
Schedule Visit 7 after 8 weeks.  
9.9
Visit 7 (Day 77)
1.     Review and record changes to concomitant medications.
2.     Perform and record vital signs.
3.     Perform and record oximetry.
4.     Perform and record urine pregnancy test. 
5.     Perform and record fractional exhaled nitric oxide (FeNO) measurement.
6.     Perform and record spirometry.
7.     Perform and record post-bronchodilator spirometry. 
8.     Obtain a CT scan of the thorax.
9.     Collect induced sputum sample.
10.     Collect blood for clinical laboratory tests.
11.     Schedule Visit 8 within 1 week. 
9.10 Visit 8 (Day 84)
1.     Review and record changes to concomitant medications.
2.     Perform and record vital signs.
3.     Perform and record oximetry.
4.     Perform and record urine pregnancy test
5.     Perform and record fractional exhaled nitric oxide (FeNO) measurement.
6.     Perform and record spirometry.
7.     Perform and record post-bronchodilator reversibility.
8.     Perform and record plethysmography with bronchodilation.
9.
Provide education on use of personal nebulizer and administration of study   
medication. 
10.
Administer first two treatments of study drug treatment, spaced 4-6 hours. FEV1 
measurements should be taken before and after each treatment. 
11.
Dispense study drug and initiate study diary if subject’s post-treatment FEV1 is  
greater than 80% of pre-treatment FEV1
12.     Schedule participant for phone follow-up in 3-5 days and visit 5 in 7 days.

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9.11  Phone follow-up (Day 86, 87, or 88)
1.       Administer questionnaire to monitor for treatment related side effects. 
9.12 Visit 9 (Day 91)
1.
Record any adverse experiences and/or review participant diary for adverse 
experiences. 
2.
Perform abbreviated physical examination.
3.
Review and record changes to concomitant medications.
4.
Record vital signs.
5.
Perform and record oximetry.
6.
Perform and record urine pregnancy test
7.
Perform and record spirometry.
8.
Perform and record post-bronchodilator spirometry.
9.
Review diary card. 
10.
Dispense remaining 7 days of study drug. 
11.
Schedule participant for Visit 10 in 7 days. 
9.13 Visit 10 (Day 98)
1.     Review and record changes to concomitant medications.
2.     Perform and record vital signs.
3.     Perform and record oximetry.
4.     Perform and record urine pregnancy test
5.
Perform and record fractional exhaled nitric oxide (FeNO) measurement.
6.
Perform and record spirometry.
7.
Perform and record post-bronchodilator reversibility. 
8.
Perform and record plethysmography with bronchodilation.
9.
Obtain a CT scan of the thorax
10.
Collect induced sputum sample
11.
Collect blood for clinical laboratory tests.
9.14 Early Withdrawal Visit
1.
Record any Adverse Experiences and/or Review participant diary for adverse 
experiences and exclusionary medication use.
2.
Review and record changes to concomitant medications.
3.
Perform abbreviated physical examination.
4.
Perform and record vital signs.
5.
Perform and record oximetry.
6.
Perform and record urine pregnancy test. 
7.
Perform and record spirometry.
8.
Perform and record post-bronchodilator spirometry.
9.
Collect any unused study drug. 
10.
Review dairy card. 
11.
Perform and record plethysmography with bronchodilation*
12.
Obtain a CT scan of the thorax*
13.
Collect induced sputum sample*

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14.
Collect blood for clinical laboratory tests*
*Subjects will only be eligible to complete post-treatment plethysmography, CT scan, 
sputum induction and blood collection if they completed a minimum of five treatment days 
or 10 treatments.  
10 ADVERSE EXPERIENCE REPORTING AND DOCUMENTATION
10.1 Adverse Events
An adverse event (AE) is any untoward medical occurrence in a clinical investigation of a 
patient administered a pharmaceutical product and that does not necessarily have a causal 
relationship with the treatment.  An AE is therefore any unfavorable and unintended sign 
(including an abnormal laboratory finding), symptom or disease temporally associated with 
the administration of an investigational product, whether or not related to that 
investigational product.  An unexpected AE is one of a type not identified in nature, 
severity, or frequency in the current Investigator’s Brochure or of greater severity or 
frequency than expected based on the information in the Investigator’s Brochure.
The Investigator will probe, via discussion with the participant, for the occurrence of AEs 
during each participant visit and record the information in the site’s source documents.  
Adverse events will be recorded in the participant CRF.  Adverse events will be described 
by duration (start and stop dates and times), severity, outcome, treatment and relation to 
study drug, or if unrelated, the cause.
AE Severity
The National Cancer Institute’s Common Terminology Criteria for Adverse Events 
(CTCAE) Version 3.0 should be used to assess and grade AE severity, including laboratory 
abnormalities judged to be clinically significant. The modified criteria can be found in the 
study manual.  If the experience is not covered in the modified criteria, the guidelines 
shown in Table  below should be used to grade severity.  It should be pointed out that the 
term “severe” is a measure of intensity and that a severe AE is not necessarily serious.
Table 3.  AE Severity Grading
Severity (Toxicity Grade)
Description
Mild (1)
Transient or mild discomfort; no limitation in activity; no medical 
intervention or therapy required. The participant may be aware of the 
sign or symptom but tolerates it reasonably well.
Moderate (2)
Mild to moderate limitation in activity, no or minimal medical 
intervention/therapy required.
Severe (3)
Marked limitation in activity, medical intervention/therapy required, 
hospitalizations possible.
Life-threatening (4)
The participant is at risk of death due to the adverse experience as it 
occurred. This does not refer to an experience that hypothetically 
might have caused death if it were more severe.
AE Relationship to Study Drug

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The relationship of an AE to the study drug should be assessed using the following the 
guidelines in Table .
Table 4.  AE Relationship to Study Drug
Relationship
to Drug
Comment
Definitely
Previously known toxicity of agent; or an event that follows a reasonable temporal 
sequence from administration of the drug; that follows a known or expected response 
pattern to the suspected drug; that is confirmed by stopping or reducing the dosage of 
the drug; and that is not explained by any other reasonable hypothesis.
Probably
An event that follows a reasonable temporal sequence from administration of the 
drug; that follows a known or expected response pattern to the suspected drug; that is 
confirmed by stopping or reducing the dosage of the drug; and that is unlikely to be 
explained by the known characteristics of the participant’s clinical state or by other 
interventions.
Possibly
An event that follows a reasonable temporal sequence from administration of the 
drug; that follows a known or expected response pattern to that suspected drug; but 
that could readily have been produced by a number of other factors.
Unrelated
An event that can be determined with certainty to have no relationship to the study 
drug.
10.2 Serious Adverse Experiences (SAE)
An SAE is defined as any AE occurring at any dose that results in any of the following 
outcomes:

death

a life-threatening adverse experience

inpatient hospitalization or prolongation of existing hospitalization

a persistent or significant disability/incapacity

a congenital anomaly/birth defect 
Other important medical events may also be considered an SAE when, based on 
appropriate medical judgment, they jeopardize the participant or require intervention to 
prevent one of the outcomes listed. 
10.2.1 Serious Adverse Experience Reporting
The study site will document all SAEs that occur (whether or not related to study drug) per 
UCSF CHR Guidelines.  The collection period for all SAEs will begin after informed 
consent is obtained and end after procedures for the final study visit have been completed.
In accordance with the standard operating procedures and policies of the local Institutional 
Review Board (IRB)/Independent Ethics Committee (IEC), the site investigator will report 
SAEs to the IRB/IEC.  
10.3 Medical Monitoring
John Fahy, MD, MSc should be contacted directly at these numbers to report medical 
concerns or questions regarding safety.

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Phone: (415) 476-9940
Mobile: (415) 317-3259
11 DISCONTINUATION AND REPLACEMENT OF PARTICIPANTS
11.1 Early Discontinuation of Study Drug 
A participant may be discontinued from study treatment at any time if the participant, the 
investigator, or the Sponsor feels that it is not in the participant’s best interest to continue.  
The following is a list of possible reasons for study treatment discontinuation: 
Participant withdrawal of consent 
Participant is not compliant with study procedures
Adverse event that in the opinion of the investigator would be in the best interest of the 
participant to discontinue study treatment
Protocol violation requiring discontinuation of study treatment
Lost to follow-up
Sponsor request for early termination of study
Positive pregnancy test (females)
If a participant is withdrawn from treatment due to an adverse event, the participant will be 
followed and treated by the Investigator until the abnormal parameter or symptom has 
resolved or stabilized.  
All participants who discontinue study treatment should come in for an early 
discontinuation visit as soon as possible.
All participants are free to withdraw from participation at any time, for any reason, 
specified or unspecified, and without prejudice.
Reasonable attempts will be made by the investigator to provide a reason for participant 
withdrawals.  The reason for the participant’s withdrawal from the study will be specified 
in the participant’s source documents. Refer to Section 10 for early termination procedures.
If the participant completes five treatment days or 10 treatments they will be eligible to 
complete post-treatment plethysmography, CT scan, sputum induction and blood collection 
during a post-treatment termination visit.  If they complete less than five treatment days or 
10 treatments.  Refer to Section 10 for early termination procedures.
11.2 Withdrawal of Participants from the Study
A participant may be withdrawn from the study at any time if the participant, the 
investigator, or the Sponsor feels that it is not in the participant’s best interest to continue.  
All participants are free to withdraw from participation at any time, for any reason, 
specified or unspecified, and without prejudice.
Reasonable attempts will be made by the investigator to provide a reason for participant 
withdrawals.  The reason for the participant’s withdrawal from the study will be specified 
in the participant’s source documents.  As noted above, participants who discontinue study 

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treatment early (i.e., they withdraw prior to Visit 10) should have an early discontinuation 
visit. Refer to Section 10 for early termination procedures.  
11.3 Replacement of Participants
Participants who withdraw from the study treatment will be replaced.  
Participants who withdraw from the study will be replaced.  
12 PROTOCOL VIOLATIONS
A protocol violation occurs when the subject or investigator fails to adhere to significant 
protocol requirements affecting the inclusion, exclusion, subject safety and primary 
endpoint criteria.  Protocol violations for this study include, but are not limited to, the 
following:
Failure to meet inclusion/exclusion criteria
Use of a prohibited concomitant medication
Failure to comply with Good Clinical Practice (GCP) guidelines will also result in a 
protocol violation. The Sponsor will determine if a protocol violation will result in 
withdrawal of a subject.
When a protocol violation occurs, it will be discussed with the investigator and a Protocol 
Violation Form detailing the violation will be generated. This form will be signed by a 
Sponsor representative and the Investigator. A copy of the form will be filed in the site’s 
regulatory binder and in the Sponsor’s files.
13 DATA SAFETY MONITORING 
Adverse events will be monitored by the Clinical PIs (Drs. Fahy, Woodruff, Peters, 
Lazarus and Zeki) in real-time. In addition, AEs will be reviewed quarterly in the regularly 
scheduled quality assurance meetings of UCSF Airway Clinical Research Center, which is 
attended by Drs. Fahy, Woodruff, Peters, and Lazarus and a UCSF patient safety 
representative.
14 STATISTICAL METHODS AND CONSIDERATIONS
Prior to the analysis of the final study data, a detailed Statistical Analysis Plan (SAP) will 
be written describing all analyses that will be performed.  The SAP will contain any 
modifications to the analysis plan described below.  
14.1 Data Sets Analyzed
All eligible participants who are randomized into the study and receive at least one dose of 
the study drug (the Safety Population) will be included in the safety analysis.
14.2 Demographic and Baseline Characteristics
The following demographic variables at screening will be summarized: race, gender, age, 
height, weight, baseline FEV1, and baseline post-bronchodilator FEV1.  

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14.3 Analysis of Primary Endpoint
The primary analysis is a paired t-test analysis of the % change in FEV1 from the start to 
the end of the two-week treatment period with two times daily NAC (Mucomyst-10). The 
secondary analysis will be to determine how the change in FEV1 relates to the change in 
CT mucus score.
14.4 Analysis of Secondary Endpoints
As a secondary analysis we will explore if NAC treatment decreases levels of NO in 
exhaled breath or the numbers of eosinophils in peripheral blood.
14.5 Interim Analysis
No interim analysis is planned. 
14.6 Sample Size
We propose a sample size of 36, which will provide us with the power to examine the 
effect of NAC in a subgroup of individuals with asthma who have CT evidence of 
intraluminal mucus and to identify the CT mucus score that performs best as a biomarker 
of treatment response to NAC. Participants will be enrolled if their CT mucus scores are ≥ 
5.0. The sample size is obtained when we factor in an effect size of 5% improvement in 
FEV1, a standard deviation for change in FEV1 of 20%, a within patient correlation for 
repeated measures of FEV1 of 0.9, and a power of 90%. 
DATA COLLECTION, RETENTION AND MONITORING
14.7 Data Collection Instruments
The Investigator will prepare and maintain adequate and accurate source documents designed 
to record all observations and other pertinent data for each participant treated with the study 
drug.  
Study personnel at each site will enter data from source documents corresponding to a 
participant’s visit into the protocol-specific paper CRF when the information corresponding 
to that visit is available. Participants will not be identified by name in the study database or 
on any study documents to be collected by the Sponsor (or designee), but will be identified 
by a site number, participant number and initials.
The Investigator is responsible for all information collected on participants enrolled in this 
study.  All data collected during the course of this study must be reviewed and verified for 
completeness and accuracy by the Investigator.  A copy of the CRF will remain at the 
Investigator’s site at the completion of the study.
14.8 Data Management Procedures
The data will be entered into a validated database.  The Data Management group will be 
responsible for data processing, in accordance with procedural documentation.  Database 
lock will occur once quality assurance procedures have been completed.

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All procedures for the handling and analysis of data will be conducted using good 
computing practices meeting FDA guidelines for the handling and analysis of data for 
clinical trials.
14.9 Data Quality Control and Reporting
After data have been entered into the study database, a system of computerized data 
validation checks will be implemented and applied to the database on a regular basis. 
Query reports (Data Clarification Requests) pertaining to data omissions and discrepancies 
will be forwarded to the clinical research coordinators for resolution. The study database 
will be updated in accordance with the resolved queries.  All changes to the study database 
will be documented.
14.10Archival of Data
The database is safeguarded against unauthorized access by established security 
procedures; appropriate backup copies of the database and related software files will be 
maintained.  Databases are backed up by the database administrator in conjunction with 
any updates or changes to the database.  
At critical junctures of the protocol (e.g., production of interim reports and final reports), 
data for analysis is locked and cleaned per established procedures.
14.11Availability and Retention of Investigational Records
The Investigator must make study data accessible to the monitor, other authorized 
representatives of the Sponsor (or designee), IRB/IEC, and Regulatory Agency (e.g., FDA) 
inspectors upon request.  A file for each participant must be maintained that includes the 
signed Informed Consent, HIPAA Authorization and Assent Form and copies of all source 
documentation related to that participant.  The Investigator must ensure the reliability and 
availability of source documents from which the information on the CRF was derived.
All study documents (patient files, signed informed consent forms, copies of CRFs, Study 
File Notebook, etc.) must be kept secured for a period of two years following marketing of 
the investigational product.  There may be other circumstances for which the Sponsor is 
required to maintain study records and, therefore, the Sponsor should be contacted prior to 
removing study records for any reason.
14.12Monitoring
Monitoring visits will be conducted by representatives of the Sponsor according to the U.S. 
CFR Title 21 Parts 50, 56, and 312 and ICH Guidelines for GCP (E6).    By signing this 
protocol, the Investigator grants permission to the Sponsor (or designee), and appropriate 
regulatory authorities to conduct on-site monitoring and/or auditing of all appropriate study 
documentation.
14.13Participant Confidentiality
In order to maintain participant confidentiality, only a site number, participant number and 
participant initials will identify all study participants on CRFs and other documentation.  

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Additional participant confidentiality issues (if applicable) are covered in the Clinical 
Study Agreement.
15 ADMINISTRATIVE, ETHICAL, REGULATORY CONSIDERATIONS
The study will be conducted according to the Declaration of Helsinki, Protection of Human 
Volunteers (21 CFR 50), Institutional Review Boards (21 CFR 56), and Obligations of 
Clinical Investigators (21 CFR 312).
To maintain confidentiality, all laboratory specimens, evaluation forms, reports and other 
records will be identified by a coded number and initials only.  All participant 
interviews/visits are conducted in private testing rooms. Information about study 
participants is kept in binders in a locked storage closet, and in our password protected 
secure electronic files, and is only accessible to authorized study personnel. Clinical 
information will not be released without written permission of the participant, except as 
necessary for monitoring by the FDA.  The Investigator must also comply with all 
applicable privacy regulations (e.g., Health Insurance Portability and Accountability Act of 
1996, EU Data Protection Directive 95/46/EC).
15.1 Protocol Amendments
Any amendment to the protocol will be written by the Sponsor.  Protocol amendments 
cannot be implemented without prior written IRB/IEC approval except as necessary to 
eliminate immediate safety hazards to patients.  A protocol amendment intended to 
eliminate an apparent immediate hazard to patients may be implemented immediately, 
provided the IRBs are notified within five working days.
15.2 Institutional Review Boards and Independent Ethics Committees
The protocol and consent form will be reviewed and approved by the IRB/IEC of each 
participating center prior to study initiation.  Serious adverse experiences regardless of 
causality will be reported to the IRB/IEC in accordance with the standard operating 
procedures and policies of the IRB/IEC, and the Investigator will keep the IRB/IEC 
informed as to the progress of the study.  The Investigator will obtain assurance of 
IRB/IEC compliance with regulations.
Any documents that the IRB/IEC may need to fulfill its responsibilities (such as protocol, 
protocol amendments, Investigator’s Brochure, consent forms, information concerning 
patient recruitment, payment or compensation procedures, or other pertinent information) 
will be submitted to the IRB/IEC.  The IRB/IECs written unconditional approval of the 
study protocol and the informed consent form will be in the possession of the Investigator 
before the study is initiated.  The IRB/IECs unconditional approval statement will be 
transmitted by the Investigator to prior to the shipment of study supplies to the site.  This 
approval must refer to the study by exact protocol title and number and should identify the 
documents reviewed and the date of review.
Protocol and/or informed consent modifications or changes may not be initiated without 
prior written IRB/IEC approval except when necessary to eliminate immediate hazards to 
the patients or when the change(s) involves only logistical or administrative aspects of the 

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study.  Such modifications will be submitted to the IRB/IEC and written verification that 
the modification was submitted and subsequently approved should be obtained.  
The IRB/IEC must be informed of revisions to other documents originally submitted for 
review; serious and/or unexpected adverse experiences occurring during the study in 
accordance with the standard operating procedures and policies of the IRB; new 
information that may affect adversely the safety of the patients of the conduct of the study; 
an annual update and/or request for re-approval; and when the study has been completed.
15.3 Informed Consent Form 
Informed consent will be obtained in accordance with the Declaration of Helsinki, ICH 
GCP, US Code of Federal Regulations for Protection of Human Subjects (21 CFR 
50.25[a,b], CFR 50.27, and CFR Part 56, Subpart A), the Health Insurance Portability and 
Accountability Act (HIPAA, if applicable), and local regulations.
The Investigator will prepare the informed consent form, assent and HIPAA authorization 
and provide the documents to the IRB/IEC for approval prior.  The consent form generated 
by the Investigator must be approved by the IRB/IEC.  The written consent document will 
embody the elements of informed consent as described in the International Conference on 
Harmonisation and will also comply with local regulations. 
A properly executed, written, informed consent will be obtained from each participant prior 
to entering the participant into the trial.  Information should be given in both oral and 
written form and participants must be given ample opportunity to inquire about details of 
the study.  A copy of the signed consent form will be given to the participant and the 
original will be maintained with the participant’s records.
15.4 Publications 
The preparation and submittal for publication of manuscripts containing the study results 
shall be in accordance with a process determined by mutual written agreement among the 
study Sponsor and participating institutions.  The publication or presentation of any study 
results shall comply with all applicable privacy laws, including, but not limited to, the 
Health Insurance Portability and Accountability Act of 1996. 
15.5
Investigator Responsibilities
By signing the Agreement of Investigator form, the Investigator agrees to:
1.
Conduct the study in accordance with the protocol and only make changes after 
notifying the Sponsor (or designee), except when to protect the safety, rights or 
welfare of participants.
2.
Personally conduct or supervise the study (or investigation).
3.
Ensure that the requirements relating to obtaining informed consent and IRB review 
and approval meet federal guidelines, as stated in § 21 CFR, parts 50 and 56.
4.
Report to the Sponsor or designee any AEs that occur in the course of the study, in 
accordance with §21 CFR 312.64.

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5.
Ensure that all associates, colleagues and employees assisting in the conduct of the 
study are informed about their obligations in meeting the above commitments.
6.
Maintain adequate and accurate records in accordance with §21 CFR 312.62 and to 
make those records available for inspection with the Sponsor (or designee).
7.
Ensure that an IRB that complies with the requirements of §21 CFR part 56 will be 
responsible for initial and continuing review and approval of the clinical study.
8.
Promptly report to the IRB and the Sponsor (or designee) all changes in the research 
activity and all unanticipated problems involving risks to participants or others (to 
include amendments and IND safety reports).
9.
Seek IRB approval before any changes are made in the research study, except when 
necessary to eliminate hazards to the patients/ participants.
10. Comply with all other requirements regarding the obligations of clinical investigators 
and all other pertinent requirements listed in § 21 CFR part 312.
Appendix A. Schedule of Study Visits (UCSF)
Visit 
1
2a
2b*
3
4
5
61
7
8
9
10
Time Commitment (hours)**
2
2
3
2
8
2
4
4
8
2
4
Consent and eligibility
x
Questionnaires
x
x
x
x
x
x
x
x
Physical Exam
x
x2
x2
x2
x2
x2
x2
Vital signs & oximetry
x
x
x
x
x
x
x
x
x
x
x
FENO
x
x
x
x
x
x
Spirometry
x
x
x
x
x
x
x
x
x
x
x

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Post-bronchodilator 
reversibility
x
x
x
x
x
x
x
x
x
Methacholine challenge
x
Urine pregnancy test
x
x
x
x
x
x
x
Sputum induction
x
x
x
x
x
Blood sample
x1
x
x
x
Plethysmography
x
x
x
x
CT thorax
x
x
x
x
Nebulizer & diary card 
education & teach-back
x
x
Medication administration
x
x
x
x
Randomization
x
* Participation in visit 2b is dependent on post-bronchodilator reversibility test results obtained at visit 2a. 
The visit 2 sputum induction will only be obtained at visit 2a or 2b.  
**Duration of visit is an estimation
1.
Blood sample to include DNA, plasma, serum and CBC with 5-part differential
2.
Abbreviated physical exam.
Appendix B. Schedule of Study Visits (UC Davis)
Visit 
1
2a
2b*
3
4
5
6
7
8
9
10
Time Commitment (hours)**
2
2
3
2
8
2
4
4
8
2
4
Consent and eligibility
x
Questionnaires
x
x
x
x
x
x
x
x
Physical Exam
x
x1
x1
x1
x1
x1
x1
Vital signs & oximetry
x
x
x
x
x
x
x
x
x
x
x
FENO
x
x
x
x
x
x
Spirometry
x
x
x
x
x
x
x
x
x
x
x
Post-bronchodilator 
reversibility
x
x
x
x
x
x
x
x
x
Methacholine challenge
x
Urine pregnancy test
x
x
x
x
x
x
x
Blood sample
x
x
x
x
Plethysmography
x
x
x
x
CT thorax
x
x
x
x
Nebulizer & diary card 
education & teach-back
x
x
Medication administration
x
x
x
x
Randomization
x
* Participation in visit 2b is dependent on post-bronchodilator reversibility test results obtained at visit 2a. 
The visit 2 sputum induction will only be obtained at visit 2a or 2b.  
**Duration of visit is an estimation
1. Abbreviated physical exam.

Protocol 18-26680                                               
Confidential
Version #6
         Version Date: 5/26/2021
41 
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asthma. N Engl J Med. 2011;365(12):1088-1098.
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3. DUNNILL MS. The pathology of asthma, with special reference to changes in the 
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efficacy of fiberoptic bronchoscopy with lavage in the management of refractory asthma 
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5. Green FH, Williams DJ, James A, McPhee LJ, Mitchell I, Mauad T. Increased 
myoepithelial cells of bronchial submucosal glands in fatal asthma. Thorax. 2010;65(1):32-
38.
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N-acetylcysteine into bronchoalveolar lavage fluid. Eur J Respir Dis. 1987;70(2):73-77.
7. McCoy K, Hamilton S, Johnson C. Effects of 12-week administration of dornase alfa in 
patients with advanced cystic fibrosis lung disease. pulmozyme study group. Chest. 
1996;110(4):889-895.