Trial · NCT04359680

Trial to Evaluate the Efficacy and Safety of Nitazoxanide (NTZ) for Pre- and Post Exposure Prophylaxis of COVID-19 and Other Viral Respiratory Illnesses (VRI) in Healthcare Workers and Others at Increased Risk of SARS-CoV-2 Infection

NCT04359680, Phase 3, Completed, Romark Laboratories L.C.; results first posted 2024-06-26

3 sourcestrials-2026-11-12-0.5.0

Cite this record

ConductScience Library. Trial to Evaluate the Efficacy and Safety of Nitazoxanide (NTZ) for Pre- and Post Exposure Prophylaxis of COVID-19 and Other Viral Respiratory Illnesses (VRI) in Healthcare Workers and Others at Increased Risk of SARS-CoV-2 Infection. Trials, record NCT04359680. Release trials-2026-11-12-0.5.0, 12 Nov 2026. https://conductscience.org/library/trials/NCT04359680

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Trial

As registered on ClinicalTrials.gov, in the graph's capture of the registry.

Title: Trial to Evaluate the Efficacy and Safety of Nitazoxanide (NTZ) for Pre- and Post Exposure Prophylaxis of COVID-19 and Other Viral Respiratory Illnesses (VRI) in Healthcare Workers and Others at Increased Risk of SARS-CoV-2 Infection
NCT number: NCT04359680
Status: Completed
Phases: Phase 3
Enrollment: 1,407 participants, actual
Lead sponsor: Romark Laboratories L.C.
Conditions: COVID-19, Viral Respiratory Illnesses
Interventions: Nitazoxanide, Placebo, Vitamin Super B-Complex
First posted: 2020-04-24
Last updated: 2024-06-26
Results first posted: 2024-06-26

Source ClinicalTrials.gov

Registered outcomes4

Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.

List	Outcome	Time frame	Description
Primary	The Proportion of Subjects With Symptomatic Laboratory-confirmed COVID-19 Identified After Start of Treatment and Before the End of the 6-week Treatment Period.	Up to 6 weeks
Primary	The Proportion of Subjects With Symptomatic Laboratory-confirmed VRI Identified After the Start of Treatment and Before the End of the 6-week Treatment Period.	Up to 6 weeks
Secondary	Proportion Experiencing Mortality Due to COVID-19 or Complications Thereof	Up to 8 weeks	Note: statistical analysis not performed because no events occurred.
Secondary	Proportion With Anti-SARS-CoV-2 Antibodies at Either of the Week 6 or Week 8 Visits	Up to 8 weeks

Source ClinicalTrials.gov

Outcomes12

Each outcome the trial posted results for, in ClinicalTrials.gov's words.

Type	Outcome	Time frame	Population	Units	Measured as
PRIMARY	The Proportion of Subjects With Symptomatic Laboratory-confirmed COVID-19 Identified After Start of Treatment and Before the End of the 6-week Treatment Period.	Up to 6 weeks	The intent-to-treat (ITT) population consists of all subjects who received at least one dose of study medication and were negative for all respiratory viruses tested at Baseline. Proportions were rounded to the nearest hundredth decimal.	proportion of participants	NUMBER
PRIMARY	The Proportion of Subjects With Symptomatic Laboratory-confirmed VRI Identified After the Start of Treatment and Before the End of the 6-week Treatment Period.	Up to 6 weeks	The intent-to-treat (ITT) population consists of all subjects who received at least one dose of study medication and were negative for all respiratory viruses tested at Baseline. Proportions were rounded to the nearest hundredth decimal.	proportion of participants	NUMBER
SECONDARY	Proportion Experiencing Mortality Due to COVID-19 or Complications Thereof	Up to 8 weeks	The intent-to-treat (ITT) population consists of all subjects who received at least one dose of study medication and were negative for all respiratory viruses tested at Baseline	proportion of participants	NUMBER
SECONDARY	Proportion With Anti-SARS-CoV-2 Antibodies at Either of the Week 6 or Week 8 Visits	Up to 8 weeks	The intent-to-treat (ITT) population consists of all subjects who received at least one dose of study medication and were negative for all respiratory viruses tested at Baseline. Proportions were rounded to the nearest hundredth decimal.	proportion of participants	NUMBER
POST_HOC	Days Not at Usual Health Due to COVID-19	Up to 56 days	Participants experiencing symptomatic COVID-19 during the study period	days	MEAN
POST_HOC	Days Unable to Perform Usual Activities Due to COVID-19	Up to 56 days	Patients with symptomatic COVID-19	days	MEAN
POST_HOC	Days Meeting Acute Respiratory Illness Symptom Severity Criteria Due to COVID-19	Up to 56 days	Patients with symptomatic COVID-19	days	MEAN
POST_HOC	Maximum Symptom Severity Due to COVID-19	Up to 56 days	Participants with symptomatic COVID-19	score on a scale	MEAN
POST_HOC	Days Not At Usual Health Due to VRI	Up to 56 days	Participants experiencing symptomatic viral respiratory illness	days	MEAN
POST_HOC	Days Unable to Perform Usual Activities Due to VRI	Up to 56 days	Participants experiencing symptomatic viral respiratory illness (VRI)	days	MEAN

1 to 10 of 12Source ClinicalTrials.gov

See all 12 outcomes

Results by group24

Each measurement the trial posted, group by group, in the words and numbers it posted.

Outcome	Group	Value	Spread	Units
The Proportion of Subjects With Symptomatic Laboratory-confirmed COVID-19 Identified After Start of Treatment and Before the End of the 6-week Treatment Period.	Nitazoxanide	0.02		proportion of participants
The Proportion of Subjects With Symptomatic Laboratory-confirmed COVID-19 Identified After Start of Treatment and Before the End of the 6-week Treatment Period.	Placebo	0.02		proportion of participants
The Proportion of Subjects With Symptomatic Laboratory-confirmed VRI Identified After the Start of Treatment and Before the End of the 6-week Treatment Period.	Nitazoxanide	0.05		proportion of participants
The Proportion of Subjects With Symptomatic Laboratory-confirmed VRI Identified After the Start of Treatment and Before the End of the 6-week Treatment Period.	Placebo	0.05		proportion of participants
Proportion Experiencing Mortality Due to COVID-19 or Complications Thereof	Nitazoxanide	0		proportion of participants
Proportion Experiencing Mortality Due to COVID-19 or Complications Thereof	Placebo	0		proportion of participants
Proportion With Anti-SARS-CoV-2 Antibodies at Either of the Week 6 or Week 8 Visits	Nitazoxanide	0.17		proportion of participants
Proportion With Anti-SARS-CoV-2 Antibodies at Either of the Week 6 or Week 8 Visits	Placebo	0.19		proportion of participants
Days Not at Usual Health Due to COVID-19	Nitazoxanide	13.2	Standard Deviation 16.88	days
Days Not at Usual Health Due to COVID-19	Placebo	19.5	Standard Deviation 14.58	days

1 to 10 of 24Source ClinicalTrials.gov

See all 24 results by group

Participant flow6

How many started, completed or left each group, period by period.

Period	Milestone	Group	Participants
Overall Study	STARTED	Nitazoxanide	711
Overall Study	STARTED	Placebo	696
Overall Study	COMPLETED	Nitazoxanide	616
Overall Study	COMPLETED	Placebo	604
Overall Study	NOT COMPLETED	Nitazoxanide	95
Overall Study	NOT COMPLETED	Placebo	92

Source ClinicalTrials.gov

Adverse events18

Each adverse event the trial posted, group by group: the participants affected out of those at risk.

Type	Event	Organ system	Group	Affected	At risk	Events
serious	Myocardial infarction	Cardiac disorders	Nitazoxanide	0	686	0
serious	Myocardial infarction	Cardiac disorders	Placebo	1	663	1
serious	Syncope	Cardiac disorders	Nitazoxanide	0	686	0
serious	Syncope	Cardiac disorders	Placebo	1	663	1
serious	Abdominal hernia	Gastrointestinal disorders	Nitazoxanide	1	686	1
serious	Abdominal hernia	Gastrointestinal disorders	Placebo	0	663	0
serious	Cholelithiasis	Hepatobiliary disorders	Nitazoxanide	0	686	0
serious	Cholelithiasis	Hepatobiliary disorders	Placebo	1	663	1
serious	Drug-induced liver injury	Hepatobiliary disorders	Nitazoxanide	1	686	1
serious	Drug-induced liver injury	Hepatobiliary disorders	Placebo	0	663	0

1 to 10 of 18Source ClinicalTrials.gov

See all 18 adverse events

Adverse event totals6

The totals the trial posted for each group.

Total	Group	Affected	At risk
Total, all-cause mortality	Nitazoxanide	0	686
Total, all-cause mortality	Placebo	0	663
Total, other adverse events	Nitazoxanide	0	686
Total, other adverse events	Placebo	0	663
Total, serious adverse events	Nitazoxanide	3	686
Total, serious adverse events	Placebo	6	663

Source ClinicalTrials.gov

Papers0

The papers the trial lists on ClinicalTrials.gov.

None in this release.

Grants0

The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.

None in this release.

Trial comparisons2

Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.

Comparison	Source
Nitazoxanide vs Placebo: deaths from any cause	Trial comparisons
Nitazoxanide vs Placebo: serious adverse events	Trial comparisons

Tests0

The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.

None in this release.

Data dates

The day each source was copied for this release.

ClinicalTrials.gov: 2026-11-12; ClinicalTrials.gov
Results, from AACT: 2026-03-23; AACT
NIH grant links: 2026-11-13; NIH RePORTER

Sources 3

ClinicalTrials.gov's posted results, through CTTI's AACTFreely available. Acknowledgement requested
ClinicalTrials.govNo license stated
NIH RePORTER's clinical studies and project filesPublic domain

Each source's terms

ClinicalTrials.gov's posted results, through CTTI's AACTClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299
ClinicalTrials.govnone stated
NIH RePORTER's clinical studies and project filesPublic domain (NIH RePORTER)

ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.

For software

Read this trial from software.

The record and each of its lists are JSON, twenty rows a page. No key.

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GET https://conductscience.org/api/trials/v1/NCT04359680/results?page=2

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