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NAC for Attenuation of COVID-19 Symptomatology (NACinCOVID2)

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ClinicalTrials.gov Identifier: NCT05074121
Recruitment Status : Not yet recruiting
First Posted : October 12, 2021
Last Update Posted : January 21, 2022
The Thoracic Foundation
Information provided by (Responsible Party):
Melisa Lai-Becker, Cambridge Health Alliance

Brief Summary:
The objective of this study is to determine whether oral NAC is effective at attenuating COVID-19 disease symptom severity and duration of symptoms.

Condition or disease Intervention/treatment Phase
Covid19 COVID-19 Pneumonia COVID-19 Respiratory Infection COVID-19 Lower Respiratory Infection SARS-CoV2 Infection SARS-CoV-2 Acute Respiratory Disease SARS-Associated Coronavirus as Cause of Disease Classified Elsewhere Oxidative Stress Drug: N-acetylcysteine Other: Placebo Phase 2

Detailed Description:

STUDY DESIGN: Randomized double-blinded placebo-controlled trial


Inclusion criteria:

  • age 18 years and older
  • participants will need daily access to use of a smartphone for at least six weeks from time of enrollment
  • Positive COVID-19 test within 10 days of date of enrollment
  • not already hospitalized for treatment of COVID

Exclusion criteria:

  • pregnant
  • already hospitalized for treatment of COVID


  • 50:50 randomization: half of participants will take NAC, half will take placebo
  • Participants will take NAC/placebo following this outpatient protocol:
  • 2400 mg x 1 PO then
  • 1200 mg PO BID x 14 days
  • Participants will complete an online symptom-tracker for six weeks (daily for three weeks, weekly for three weeks)

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 200 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description: Randomized Double-Blinded Placebo-Controlled
Masking: Triple (Participant, Care Provider, Investigator)
Masking Description: Participants and study team members will be masked to whether a participant is receiving the study drug or placebo
Primary Purpose: Treatment
Official Title: N-acetylcysteine for Attenuation of COVID Symptomatology
Estimated Study Start Date : March 31, 2022
Estimated Primary Completion Date : December 31, 2022
Estimated Study Completion Date : February 1, 2023

Arm Intervention/treatment
Experimental: NAC
Group receiving intervention/study drug NAC
Drug: N-acetylcysteine
Other Names:
  • NAC
  • N-acetyl-cysteine
  • Acetylcysteine

Placebo Comparator: Placebo
Group receiving placebo
Other: Placebo

Primary Outcome Measures :
  1. Symptom severity [ Time Frame: 24 weeks starting the day after enrollment ]
    Severity of symptoms

  2. Symptom duration [ Time Frame: 24 weeks starting the day after enrollment ]
    Length in days of symptoms

Secondary Outcome Measures :
  1. Need for higher level of care/hospitalization [ Time Frame: 24 weeks starting the day after enrollment ]
    Comparison between groups of rates of hospitalization

Information from the National Library of Medicine

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

Inclusion Criteria:

  • positive COVID test <= 7 days of enrollment

Exclusion Criteria:

  • pregnant
  • already hospitalized due to COVID

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): NCT05074121

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Contact: Melisa Lai-Becker, MD 617-394-7424 melaibecker@cha.harvard.edu
Contact: Tom Seufert, MD tseufert@cha.harvard.edu

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United States, Massachusetts
Cambridge Health Alliance
Everett, Massachusetts, United States, 02149
Contact: Melisa Lai-Becker, MD       melaibecker@cha.harvard.edu   
Contact: Tom Seufert, MD       tseufert@cha.harvard.edu   
Sponsors and Collaborators
Cambridge Health Alliance
The Thoracic Foundation
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Responsible Party: Melisa Lai-Becker, Chief, CHA Everett Emergency Department; Director, CHA Division of Medical Toxicology, Cambridge Health Alliance
ClinicalTrials.gov Identifier: NCT05074121    
First Posted: October 12, 2021    Key Record Dates
Last Update Posted: January 21, 2022
Last Verified: January 2022
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Yes
Plan Description: Study data used for publication
Supporting Materials: Study Protocol
Informed Consent Form (ICF)
Time Frame: Available six months after publication for one year
URL: http://www.NACinCOVID.info

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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
Keywords provided by Melisa Lai-Becker, Cambridge Health Alliance:
Additional relevant MeSH terms:
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Communicable Diseases
Respiratory Tract Infections
Severe Acute Respiratory Syndrome
Respiration Disorders
Respiratory Tract Diseases
Disease Attributes
Pathologic Processes
Pneumonia, Viral
Virus Diseases
Coronavirus Infections
Coronaviridae Infections
Nidovirales Infections
RNA Virus Infections
Lung Diseases
Antiviral Agents
Anti-Infective Agents
Respiratory System Agents
Free Radical Scavengers
Molecular Mechanisms of Pharmacological Action
Protective Agents
Physiological Effects of Drugs