Covid-19Phase 2NCT04374461
A Study of N-acetylcysteine in Patients With COVID-19 Infection
A Phase 2 study testing N-acetylcysteine and Peripheral Blood in people with Covid-19, run by Memorial Sloan Kettering Cancer Center at 1 site in United States.
Trial summary
The study researchers think that a medication called N-acetylcysteine can help fight the COVID-19 virus by boosting a type of cell in your immune system that attacks infections. By helping your immune system fight the virus, the researchers think that the infection will get better, which could allow the patient to be… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Covid-19
- What is being tested?
- N-acetylcysteine and Peripheral Blood
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 48 participants
- Where
- 1 siteUnited States
- Study dates
- 1 May 2020to May 2027
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Documented COVID-19 infection (either performed on site or documented external report)
- Age ≥ 18
- Arm A:
- Admission to an intensive care unit at MSK (M-11) and/or receiving mechanical ventilation
- Absolute lymphocyte count ≤ 1.0/mm3
- As the ALC of patients with lymphoid malignancies is unreliable, they may be enrolled at the discretion of the treating physician after review of their blood work.
- Arm B:
- Arm B:Requiring 2L or more of supplemental oxygen by nasal cannula or higher to maintain SpO2 of 95%
Who cannot join
- Arm B:
- requiring mechanical ventilation or admission to an intensive care unit at MSK (M11)
Trial locations and contacts
1 site in 1 country.
United States1 site
Memorial Sloan Kettering Cancer Center
New York, New York, 10065
About this study
Official title: Phase II Study of N-acetylcysteine in Severe or Critically Ill Patients With Refractory COVID-19 Infection
The study researchers think that a medication called N-acetylcysteine can help fight the COVID-19 virus by boosting a type of cell in your immune system that attacks infections. By helping your immune system fight the virus, the researchers think that the infection will get better, which could allow the patient to be moved out of the critical care unit or go off a ventilator, or prevent them from moving into a critical care unit or going on a ventilator.
The US Food and Drug Administration (FDA) has approved N-acetylcysteine to treat the liver side effects resulting from an overdose of the anti-inflammatory medication Tylenol® (acetaminophen). N-acetylcysteine is also used to loosen the thick mucus in the lungs of people with cystic fibrosis or chronic obstructive pulmonary disease (COPD). This study is the first to test N-acetylcysteine in people with severe COVID-19 infections.
- Conditions
- Covid-19
- Being tested
- N-acetylcysteine, Peripheral Blood
- Keywords
- N-acetylcysteine, 20-168
- Medical subject headings
- COVID-19
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
N-acetylcysteineDrug
Patients in both arms will receive N-acetylcysteine IV 6 g/day in addition to supportive and/or COVID-19 directed treatments at the discretion of the treating physician. Treatment interruptions for up to 48 hours are permissible if there is a clinical indication to hold the study drug. Patients can restart drug if they have been off drug for less than 48 hours. Patients are also eligible to restart N-acetylcysteine treatment on the same treatment arm without reconsent if they are within the 30 day followup period after their prior course of treatment on this protocol.
Peripheral BloodOther
A total of 16mL of research whole blood will be collected in CPT tubes at baseline, Cycle 2 Day 1 (or as close as feasible, when still coordinating sample collection across patients in a critical-care unit), and at end of study.
| Study group | Role | What they receive |
|---|---|---|
| mechanically ventilated &/or managed in a critical-care | Experimental | This arm is closed to accrual as of September 2020. Patients in both arms will receive N-acetylcysteine IV 6 g/day in addition to supportive and/or COVID-19 directed treatments at the discretion of the treating physician.
Patients will receive treatment for a maximum of 3 weeks or until one of the following:
Arm A:
* Transfer out of the critical-care unit
* Extubation
* Toxicity
* Death Receives: Drug: N-acetylcysteine; Other: Peripheral Blood |
| non-mechanically ventilated, non-critical-care | Experimental | Patients in both arms will receive N-acetylcysteine IV 6 g/day in addition to supportive and/or COVID-19 directed treatments at the discretion of the treating physician.
Patients will receive treatment for a maximum of 3 weeks or until one of the following:
Arm B:
* Discharge from hospital
* Admission to a critical-care unit
* Intubation
* Toxicity
* Death Receives: Drug: N-acetylcysteine; Other: Peripheral Blood |
What is being measured
The primary outcome is the main question the study is designed to answer.
Arm A: number of patients who are successfully extubated and/or transferred out of critical care due to clinical improvement
Measured: 1 year
Arm B: number of patients who are discharged from the hospital due to clinical improvement
Measured: 1 year
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 May 2020
- Study start1 May 2020
- Primary completionMay 2027 (estimated)
- Study completionMay 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Covid-19Studies of the same condition, open and under way.
- More trials run by Memorial Sloan Kettering Cancer CenterThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Model description
- This is a single-institution study that will be open at MSKCC's Manhattan campus. Patients will be enrolled into 2 separate arms. The mechanically ventilated \&/or managed in a critical-care arm is closed to accrual as of September 2020.
- Masking
- None (open label)
- Enrolment
- 48 participants (actual)
Sponsor and investigators
- Lead sponsor
- Memorial Sloan Kettering Cancer Center
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Santosha Vardhana, MD, PhD, Principal investigator, Memorial Sloan Kettering Cancer Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04374461
- Sponsor's protocol ID
- 20-168
- Status last verified
- Apr 2026
- First submitted
- 1 May 2020
- Last updated
- 1 May 2026
- Results posted
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: Memorial Sloan Kettering Cancer Center supports the international committee of medical journal editors (ICMJE) and the ethical obligation of responsible sharing of data from clinical trials. The protocol summary, a statistical summary, and informed consent form will be made available on clinicaltrials.gov when required as a condition of Federal awards, other agreements supporting the research and/or as otherwise required. Requests for deidentified individual participant data can be made beginning 12 months after publication and for up to 36 months post publication. Deidentified individual participant data reported in the manuscript will be shared under the terms of a Data Use Agreement and may only be used for approved proposals. Requests may be made to: crdatashare@mskcc.org.
Study at a glance
From the registry record, last updated by the sponsor on 1 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Phase II Study of N-acetylcysteine in Severe or Critically Ill Patients With Refractory COVID-19 Infection
- ClinicalTrials.gov ID
- NCT04374461
- Acronym / sponsor ID
- 20-168
- Conditions
- Covid-19
- Keywords
- N-acetylcysteine, 20-168
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 48 participants (actual)
- Lead sponsor
- Memorial Sloan Kettering Cancer CenterUniversity, hospital or other
- Study start
- 1 May 2020 (actual)
- Primary completion
- May 2027 (estimated)
- Study completion
- May 2027 (estimated)
- First posted
- 5 May 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The study researchers think that a medication called N-acetylcysteine can help fight the COVID-19 virus by boosting a type of cell in your immune system that attacks infections. By helping your immune system fight the virus, the researchers think that the infection will get better, which could allow the patient to be moved out of the critical care unit or go off a ventilator, or prevent them from moving into a critical care unit or going on a ventilator.
The US Food and Drug Administration (FDA) has approved N-acetylcysteine to treat the liver side effects resulting from an overdose of the anti-inflammatory medication Tylenol® (acetaminophen). N-acetylcysteine is also used to loosen the thick mucus in the lungs of people with cystic fibrosis or chronic obstructive pulmonary disease (COPD). This study is the first to test N-acetylcysteine in people with severe COVID-19 infections.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- This is a single-institution study that will be open at MSKCC's Manhattan campus. Patients will be enrolled into 2 separate arms. The mechanically ventilated \&/or managed in a critical-care arm is closed to accrual as of September 2020.
| Arm | Type | Receives |
|---|---|---|
| mechanically ventilated &/or managed in a critical-care | Experimental | Drug: N-acetylcysteine, Other: Peripheral BloodThis arm is closed to accrual as of September 2020. Patients in both arms will receive N-acetylcysteine IV 6 g/day in addition to supportive and/or COVID-19 directed treatments at the discretion of the treating physician. Patients will receive treatment for a maximum of 3 weeks or until one of the following: Arm A: * Transfer out of the critical-care unit * Extubation * Toxicity * Death |
| non-mechanically ventilated, non-critical-care | Experimental | Drug: N-acetylcysteine, Other: Peripheral BloodPatients in both arms will receive N-acetylcysteine IV 6 g/day in addition to supportive and/or COVID-19 directed treatments at the discretion of the treating physician. Patients will receive treatment for a maximum of 3 weeks or until one of the following: Arm B: * Discharge from hospital * Admission to a critical-care unit * Intubation * Toxicity * Death |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (8 listed)
- Documented COVID-19 infection (either performed on site or documented external report)
- Age ≥ 18
- Admission to an intensive care unit at MSK (M-11) and/or receiving mechanical ventilation
- Absolute lymphocyte count ≤ 1.0/mm3
- As the ALC of patients with lymphoid malignancies is unreliable, they may be enrolled at the discretion of the treating physician after review of their blood work.
Key exclusion criteria (2 listed)
- requiring mechanical ventilation or admission to an intensive care unit at MSK (M11)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| N-acetylcysteinePatients in both arms will receive N-acetylcysteine IV 6 g/day in addition to supportive and/or COVID-19 directed treatments at the discretion of the treating physician. Treatment interruptions for up to 48 hours are permissible if there is a clinical indication to hold the study drug. Patients can restart drug if they have been off drug for less than 48 hours. Patients are also eligible to restart N-acetylcysteine treatment on the same treatment arm without reconsent if they are within the 30 day followup period after their prior course of treatment on this protocol. | Drug | mechanically ventilated &/or managed in a critical-care, non-mechanically ventilated, non-critical-care |
| Peripheral BloodA total of 16mL of research whole blood will be collected in CPT tubes at baseline, Cycle 2 Day 1 (or as close as feasible, when still coordinating sample collection across patients in a critical-care unit), and at end of study. | Other | mechanically ventilated &/or managed in a critical-care, non-mechanically ventilated, non-critical-care |
Primary outcome
Arm A: number of patients who are successfully extubated and/or transferred out of critical care due to clinical improvement
Time frame: 1 year
Arm B: number of patients who are discharged from the hospital due to clinical improvement
Time frame: 1 year
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 1 May 2026.
- Memorial Sloan Kettering Cancer CenterLink provided by the sponsor.
- Individual participant dataSharing planned: Yes. Memorial Sloan Kettering Cancer Center supports the international committee of medical journal editors (ICMJE) and the ethical obligation of responsible sharing of data from clinical trials. The protocol summary, a statistical summary, and informed consent form will be made available on clinicaltrials.gov when required as a condition of Federal awards, other agreements supporting the research and/or as otherwise required. Requests for deidentified individual participant data can be made beginning 12 months after publication and for up to 36 months post publication. Deidentified individual participant data reported in the manuscript will be shared under the terms of a Data Use Agreement and may only be used for approved proposals. Requests may be made to: crdatashare@mskcc.org.
Related trials for Covid-19
Recruiting
Home-Based Exercise Tele-Rehabilitation After COVID-19
Post SARS-CoV2 (COVID-19)
RecruitingObservational study
Cardiovascular Disease Progression in Survivors of Community Acquired Pneumonia and Lung Infection by Covid-19.
Pneumonia, Community-Acquired, COVID-19 Pneumonia
RecruitingPhase 3
A Clinical Study of Molnupiravir to Prevent Severe Illness From Coronavirus Disease 2019 (COVID-19) in People Who Are High Risk (MK-4482-023)
Coronavirus Disease (COVID-19)
Not yet recruitingPhase 1
Phase I Open-Label Safety Trial of Pembrolizumab for Neurological Post- Acute Sequelae of SARS-CoV-2 (PD1-PASC I)
Post-Acute COVID-19 Syndrome
Active, not recruitingPhase 1
A Safety and Immunogenicity Trial of OCU500, ChAd36 Vector Encoding SARS-CoV-2 Spike Vaccine Via Intranasal and Inhalational Routes in Previously Vaccinated Adults
COVID-19
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Santosha Vardhana, MD, PhD principal investigator
Memorial Sloan Kettering Cancer Center
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing N-acetylcysteine and Peripheral Blood in people with Covid-19, run by Memorial Sloan Kettering Cancer Center at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 8 inclusion and 2 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 1 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Arm A: number of patients who are successfully extubated and/or transferred out of critical care due to clinical improvement (time frame: 1 year). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 1 May 2026; AzTrials last refreshed its copy on 8 Nov 2026.