We're building a better ClinicalTrials.gov. Check it out and tell us what you think!
ClinicalTrials.gov Menu

Efficacy of N-Acetylcysteine (NAC) in Preventing COVID-19 From Progressing to Severe Disease

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
ClinicalTrials.gov Identifier: NCT04419025
Recruitment Status : Completed
First Posted : June 5, 2020
Last Update Posted : May 28, 2021
Information provided by (Responsible Party):
Melisa Lai-Becker, Cambridge Health Alliance

Brief Summary:
The purpose of this study is to assess the efficacy of N-acetylcysteine (NAC) in preventing those with mild or moderate COVID-19 from progressing to severe disease

Condition or disease Intervention/treatment Phase
COVID Sars-CoV2 SARS-Associated Coronavirus as Cause of Disease Classified Elsewhere Oxidative Stress Drug: N-acetylcysteine Phase 2

Detailed Description:

After being informed of the study and potential risks and benefits, patients meeting eligibility requirements will be randomized to receive oral N-acetylcysteine (NAC) as follows:


  • N-acetylcystine (NAC) 25 mg/kg PO (rounded up to the nearest 600 mg) q4hrs until discharge
  • N-acetylcysteine (NAC) 1200 mg PO BID x 1 week post-discharge


- N-acetylcysteine (NAC) 2400 mg PO x 1 then 1200 mg PO BID x 2 weeks

Layout table for study information
Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 165 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description:

Participants are assigned to one of two groups in parallel for the duration of the study.

One arm is the intervention arm - those receiving N-acetylcysteine (NAC). One arm is the control group - those not receiving N-acetylcysteine (NAC).

Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Determination of Efficacy of N-Acetylcysteine in Preventing Those With Mild or Moderate COVID-19 From Progressing to Severe Disease
Actual Study Start Date : September 23, 2020
Actual Primary Completion Date : May 14, 2021
Actual Study Completion Date : May 14, 2021

Arm Intervention/treatment
Active Comparator: NAC
Patients receiving N-acetylcysteine (NAC)
Drug: N-acetylcysteine
Oral formulation: 600 mg capsules of N-acetylcysteine
Other Name: NAC, acetylcysteine, N-acetyl-L-cysteine, NALC

No Intervention: Control
Patients not receiving N-acetylcysteine (NAC)

Primary Outcome Measures :
  1. Decrease in Respiratory Rate [ Time Frame: First hour after first dose of NAC ]
    Decrease in dyspnea measured by respiratory rate (RR)

  2. Hospital length of stay (LOS) [ Time Frame: Through study completion, average 9 months ]
    Hospital LOS for admitted patients

  3. Need for mechanical ventilation [ Time Frame: Through study completion, average 9 months ]
    Whether a patient needed mechanical ventilation (intubation)

  4. Length of time intubated [ Time Frame: Through study completion, average 9 months ]
    If intubated, how long needing mechanical ventilation

  5. Need for hospitalization [ Time Frame: Through study completion, average 9 months ]
    Outpatients on NAC needing admission to the hospital

  6. Recovery disposition [ Time Frame: Through study completion, average 9 months ]
    Whether outpatients continued to recover as outpatients; whether admitted patients were managed on medical floors or level of care increased to ICU level of care; whether patients expired

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Layout table for eligibility information
Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • known or suspect COVID-19 disease AND one or more of the following influenza-like symptoms, including: diarrhea vomiting fever (subjective or measured) chills myalgias fatigue sore throat headache cough nasal/sinus congestion or rhinorrhea shortness of breath chest pain

Exclusion Criteria:

  • Minors, pregnant women and people unable to provide informed consent are excluded from this study

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): NCT04419025

Layout table for location information
United States, Massachusetts
CHA Cambridge Hospital
Cambridge, Massachusetts, United States, 02138
CHA Everett Hospital
Everett, Massachusetts, United States, 02149
CHA Respiratory Clinic
Somerville, Massachusetts, United States, 02143
CHA Somerville campus
Somerville, Massachusetts, United States, 02144
Sponsors and Collaborators
Cambridge Health Alliance
Additional Information:
Layout table for additonal information
Responsible Party: Melisa Lai-Becker, Chief, CHA Everett Hospital Emergency Department; Director, CHA Division of Medical Toxicology, Cambridge Health Alliance
ClinicalTrials.gov Identifier: NCT04419025    
Other Study ID Numbers: CHA-IRB-1139/05/20
First Posted: June 5, 2020    Key Record Dates
Last Update Posted: May 28, 2021
Last Verified: May 2021
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Yes
Plan Description: Information that underlies results in published data
Supporting Materials: Study Protocol
Informed Consent Form (ICF)
Time Frame: Six months after publication available for a year
Access Criteria: Written request; to be reviewed by the PI
URL: http://www.NACinCOVID.info

Layout table for additional information
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.: Yes
Keywords provided by Melisa Lai-Becker, Cambridge Health Alliance:
Oxidative stress
Additional relevant MeSH terms:
Layout table for MeSH terms
Coronavirus Infections
Severe Acute Respiratory Syndrome
Respiratory Tract Infections
Pneumonia, Viral
Virus Diseases
Coronaviridae Infections
Nidovirales Infections
RNA Virus Infections
Lung Diseases
Respiratory Tract Diseases
Antiviral Agents
Anti-Infective Agents
Respiratory System Agents
Free Radical Scavengers
Molecular Mechanisms of Pharmacological Action
Protective Agents
Physiological Effects of Drugs