Completed

A Phase II Multicenter Efficacy, Safety and Dose-Effect Study of the Expectorant Activity of Oral N-acetylcystein (NAC) in Patients With Stable, Chronic Bronchitis

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What is being tested

Data Collection

Who is being recruted

Acute Disease
+10

+ Bronchial Diseases
+ Bronchitis
From 18 to 75 Years
See all eligibility criteria
How is the trial designed

Treatment Study

Phase 2
Interventional
Study Start: January 1997
See protocol details

Summary

Principal SponsorWake Forest University
Last updated: January 13, 2026
Sourced from a government-validated database.Claim as a partner
Study start date: January 1, 1997Actual date on which the first participant was enrolled.

This is a randonmized, masked, placebo-controlled parallel group, clinical trial to evaluate the effects of three different doses of N-acetyl L-cysteine (NAC) and placebo on patient safety and on physical and transport properties of expectorated sputum. Patient sumptoms, quality of life and exacerbation will also be followed as well as pulmonary function testing and functional exercise capacity. We hypothesized that a prolongeed course of oral NAC favorably affects the morbidity of chronic bronchitis, particularly the incidence of acute exacerbations.

Official TitleA Phase II Multicenter Efficacy, Safety and Dose-Effect Study of the Expectorant Activity of Oral N-acetylcystein (NAC) in Patients With Stable, Chronic Bronchitis 
NCT00205647
Principal SponsorWake Forest University
Last updated: January 13, 2026
Sourced from a government-validated database.Claim as a partner

Protocol

This section provides details of the study plan, including how the study is designed and what the study is measuring.
Design Details
240 patients to be enrolledTotal number of participants that the clinical trial aims to recruit.
Treatment Study
These studies test new ways to treat a disease, condition, or health issue. The goal is to see if a new drug, therapy, or approach works better or has fewer side effects than existing options.

How participants are assigned to different groups/arms
In this clinical study, participants are placed into groups randomly, like flipping a coin. This ensures that the study is fair and unbiased, making the results more reliable. By assigning participants by chance, researchers can better compare treatments without external influences.

Other Ways to Assign Participants
Non-randomized allocation: Participants are assigned based on specific factors, such as their medical condition or a doctor's decision.
None (Single-arm trial): If the study has only one group, all participants receive the same treatment, and no allocation is needed.

How treatments are given to participants
Participants are divided into different groups, each receiving a specific treatment at the same time. This helps researchers compare how well different treatments work against each other.

Other Ways to Assign Treatments
Single-group assignment: Everyone gets the same treatment.
Cross-over assignment: Participants switch between treatments during the study.
Factorial assignment: Participants receive different combinations of treatments.
Sequential assignment: Participants receive treatments one after another in a specific order, possibly based on individual responses.
Other assignment: Treatment assignment does not follow a standard or predefined design.

How the interventions assigned to participants is kept confidential
Neither participants nor researchers know who is receiving which treatment. This is the most rigorous way to reduce bias, ensuring that expectations do not influence the results.

Other Ways to Mask Information
Open-label: Everyone knows which treatment is being given.
Single-blind: Participants do not know which treatment they are receiving, but researchers do.
Triple-blind: Participants, researchers, and outcome assessors do not know which treatment is given.
Quadruple-blind: Participants, researchers, outcome assessors, and care providers all do not know which treatment is given.

Eligibility

Researchers look for people who fit a certain description, called eligibility criteria: person's general health condition or prior treatments.
Conditions
Criteria
Any sexBiological sex of participants that are eligible to enroll.
From 18 to 75 YearsRange of ages for which participants are eligible to join.
Healthy volunteers not allowedIf individuals who are healthy and do not have the condition being studied can participate.
Conditions
Pathology
Acute Disease
Bronchial Diseases
Bronchitis
Chronic Disease
Infections
Lung Diseases
Lung Diseases, Obstructive
Pathologic Processes
Respiratory Tract Diseases
Respiratory Tract Infections
Disease Attributes
Pulmonary Disease, Chronic Obstructive
Bronchitis, Chronic
Criteria

Inclusion Criteria: * Smokers (past or current,20 pack years) with diagnosis of chronic bronchitis * expectorate sputum daily * FEV1 of 40-70% * understand and fill out questionnaire daily Exclusion Criteria: * other investigational within 30 days * change in smoking habit within 6 months * pulmonary diagnosis other that chronic bronchitis * significant renal, cardiac, hepatic or endocrine diseases * psychiatric disorder or evidence of alcoholism or drug abuse within year

Study Plan

Find out more about all the medication administered in this study, their detailed description and what they involve.
Study Objectives
Study Objectives
Primary Objectives

Secondary Objectives

Study Centers

These are the hospitals, clinics, or research facilities where the trial is being conducted. You can find the location closest to you and its status.
This study has 1 location
Suspended
Wake Forest University Health SciencesWinston-Salem, United StatesSee the location
CompletedOne Study Center