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The Effect of NAC on Lung Function and CT Mucus Score (ENACT)

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ClinicalTrials.gov Identifier: NCT03822637
Recruitment Status : Recruiting
First Posted : January 30, 2019
Last Update Posted : February 1, 2022
Information provided by (Responsible Party):
University of California, San Francisco

Brief Summary:
This study evaluates 20% n-acetylcysteine (NAC) in the treatment of moderate-to-severe asthma that is complicated by mucus in the airway, as determined by CT imaging. The study is a crossover design, which means that half the study participants will get 20% NAC in the first 14-day treatment period and placebo in the next 14-day treatment period; and the other half will get placebo in the first 14-day treatment period and 20% NAC in the next 14-day treatment period.

Condition or disease Intervention/treatment Phase
Asthma Drug: n-acetylcystine + albuterol Drug: 0.9% saline + albuterol Phase 4

Detailed Description:

N-acetylcystine (NAC) is a mucolytic medication, meaning that it breaks apart mucus. Investigators know that mucus is a factor in severe asthma attacks. However, mucus may be a factor in chronic severe asthma as well. This role has been hard to prove because of difficulty in showing that mucus occludes the lumen in chronic severe disease. Using a novel approach of scoring mucus occlusion, investigators have used CT imaging to uncover that a majority of people with severe asthma 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 NAC, have not shown benefit in other obstructive lung diseases, like Chronic Obstructive Pulmonary Disease (COPD). However, utilizing CT mucus scores as a biomarker, investigators believe that mucolytic treatment may prove useful for those with significant mucus impaction.

This is a randomized, double-blind, placebo-controlled phase 4 study of 20% NAC in patients with asthma who also have evidence of mucus in their lungs as determined by CT imaging. Investigators hypothesize that by treating asthmatics, chosen based on the presence of mucus in the airways, with a mucolytic like NAC, will result in an improvement of lung function.

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 30 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary Purpose: Treatment
Official Title: The Effect of NAC on Lung Function and CT Mucus Score
Actual Study Start Date : February 20, 2019
Estimated Primary Completion Date : March 2022
Estimated Study Completion Date : March 2022

Arm Intervention/treatment
Experimental: 20% n-acetylcystine (NAC)
NAC (trade name: Mucomyst) is manufactured by American Regent. The active drug studied here is 20% NAC coadministered with albuterol and delivered via nebulizer three times per day for fourteen days.
Drug: n-acetylcystine + albuterol
NAC is a mucolytic drug and Albuterol is a bronchodilator.
Other Names:
  • Mucomyst
  • NAC
  • n-acetylcystine

Placebo Comparator: 0.9% saline
Normal saline will be coadministered with albuterol as the placebo agent via a nebulizer three times per day for fourteen days.
Drug: 0.9% saline + albuterol
Normal saline is a placebo agent and Albuterol is a bronchodilator.
Other Name: Normal saline

Primary Outcome Measures :
  1. Change in FEV1 [ Time Frame: Through study completion, an average of 9 weeks ]
    The primary outcome is the % change in FEV1 from the start to the end of each two-week treatment period (either placebo or 20% NAC).

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 80 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

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 American Thoracic Society (ATS) criteria
  4. Physiological evidence of airflow obstruction (FEV1 bronchodilator reversibility of ≥ 12% or hyperreactivity to methacholine reflected by a methacholine provocative concentration that results in a 20% fall in FEV1(PC20) ≤ 16 mg/mL)
  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
  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. Adherence to study drug ≤ 70% after first treatment period
  5. Current participation in an investigational drug trial
  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

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03822637

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Contact: Xavier Orain, BS 415-502-3472 xavier.orain@ucsf.edu

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United States, California
UCSF Airway Clinical Research Center Recruiting
San Francisco, California, United States, 94143
Contact: Ariana Baum, BA    415-514-1539    ariana.baum@ucsf.edu   
Sponsors and Collaborators
University of California, San Francisco
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Principal Investigator: John Fahy, M.D, M.Sc. University of California, San Francisco
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Responsible Party: University of California, San Francisco
ClinicalTrials.gov Identifier: NCT03822637    
Other Study ID Numbers: 18-26680
First Posted: January 30, 2019    Key Record Dates
Last Update Posted: February 1, 2022
Last Verified: January 2022
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

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Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No
Product Manufactured in and Exported from the U.S.: No
Additional relevant MeSH terms:
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Bronchodilator Agents
Autonomic Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs
Anti-Asthmatic Agents
Respiratory System Agents
Tocolytic Agents
Reproductive Control Agents
Adrenergic beta-2 Receptor Agonists
Adrenergic beta-Agonists
Adrenergic Agonists
Adrenergic Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Antiviral Agents
Anti-Infective Agents
Free Radical Scavengers
Protective Agents