Gastroenteritis NorovirusPhase 2NCT03395405
NNITS-Nitazoxanide for Norovirus in Transplant Patients Study
A Phase 2 study testing Nitazoxanide in people with Gastroenteritis Norovirus, run by National Institute of Allergy and Infectious Diseases (NIAID) at 12 sites in United States.
Trial summary
This is a phase 2 multi-center, double-blind, placebo-controlled study of the efficacy and safety of nitazoxanide for the treatment of solid organ and hematopoietic stem cell transplant recipients with symptomatic diarrhea due to Norovirus. Read more about this study
- Who is it for?
- Ages 12 to 99 years
- Conditions the study is for
- Gastroenteritis Norovirus
- What is being tested?
- Nitazoxanide
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 31 participants
- Where
- 12 sitesUnited States
- Study dates
- 15 Oct 2018to 24 Aug 2021
- Phase
- Phase 2
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
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 12 to 99 years
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Who may be able to join
- Subjects should meet all of the following inclusion criteria:
- Male or female age > / = 12 years.
- Recipient of a solid organ or hematopoietic stem cell transplant.
- Positive test result for Norovirus within 14 days of enrollment that is obtained as part of routine clinical care using a Norovirus testing available to the site.
- Active GI symptoms (diarrhea, or vomiting) that, in the opinion of the PI, are secondary to Norovirus. Patients must have active diarrhea, which is defined as at least 3 days of Bristol 6 or 7 stools in the past 2 weeks prior to enrollment per patient report.
- Willing and able to provide written informed consent and assent before initiation of any study procedures, consistent with local IRB policy.
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- Subjects must be of non-childbearing potential or if of childbearing potential, must be using an effective method of birth control or must be abstinent.
- Non-childbearing potential is defined as surgically sterile or postmenopausal for > one year.
- Effective methods of birth control include the use of hormonal or barrier birth control such as implants, injectable contraceptives, combined oral contraceptives, intrauterine devices (IUDs),or condoms with spermicidal agents during study period. Female subjects must be using an effective method of birth control or practice abstinence and must agree to continue such precautions during the study and for 30 days after the Day 28 study visit.
- A woman is eligible if she is monogamous with a vasectomized male.This subject is considered low risk and not required to use contraception.
- Agrees to complete all screening requirements, study visits and procedures.
Who cannot join
- Subjects meeting any of the exclusion criteria at baseline will be excluded from study participation:
- Other identified infectious causes of diarrhea at screening. Alternative diagnosis requiring treatment would be considered a co-infection; if the testing is positive for a pathogen that the PI does not feel is causing the symptoms, they may be included but the PI or his/her designee must document that the positive test is not clinically significant, does not require treatment and is not causing the symptoms making the patient eligible for enrollment.
- Any condition that would, in opinion of the Site Investigator, place the subject at an unacceptable risk of injury or render the subject unable to meet the requirements of the protocol.
- Subjects receiving oral or intravenous immunoglobulin therapy concurrently or in the 14 days prior to enrollment.
- Nitazoxanide use for any illness in the previous 30 days prior to randomization.
- Have received experimental products within 30 days prior to the study entry or plan to receive experimental products at any time during the study
Show all 10Show fewer
- Known sensitivity to nitazoxanide or any of the excipients comprising the nitazoxanide tablets.
- Subjects unable to swallow oral medications.
- Subjects with ostomy.
- Women who are pregnant or lactating or have a positive urine pregnancy test at screening/enrollment/Day 1.
Trial locations and contacts
12 sites in 1 country.
12 sites in 1 country
United States12 sites
University of Michigan School of Public Health - Epidemiology
Ann Arbor, Michigan, 48109-2029
University of Michigan - Infectious Disease Clinic at Taubman Center
Ann Arbor, Michigan, 48109
Johns Hopkins Hospital - Medicine - Infectious Diseases
Baltimore, Maryland, 21287-0005
Northwestern University - Comprehensive Transplant Center
Chicago, Illinois, 60611-2927
Cincinnati Children's Hospital Medical Center Vaccine Research Center
Cincinnati, Ohio, 45229-3039
University of Texas Southwestern Medical Center - Internal Medicine Subspecialties Clinic
Dallas, Texas, 75390-8884
University of Kansas Medical Center - Infectious Diseases
Kansas City, Kansas, 66160-8500
University of Nebraska Medical Center - Infectious Diseases
Omaha, Nebraska, 68198-5400
University of Pittsburgh - Medicine - Infectious Diseases
Pittsburgh, Pennsylvania, 15213-3403
Children's Hospital of Pittsburgh of UPMC - Pediatric Infectious Diseases
Pittsburgh, Pennsylvania, 15224-1529
Fred Hutchinson Cancer Research Center - Vaccine and Infectious Diseases
Seattle, Washington, 98109-4433
University of Washington - Medicine
Seattle, Washington, 98195-7110
About this study
Official title: A Phase 2 Multi-Center, Prospective, Randomized, Double-Blind Study to Assess the Clinical and Antiviral Efficacy and Safety of Nitazoxanide for the Treatment of Norovirus in Hematopoietic Stem Cell and Solid Organ Transplant Recipients
This is a phase 2 multi-center, double-blind, placebo-controlled study of the efficacy and safety of nitazoxanide for the treatment of solid organ and hematopoietic stem cell transplant recipients with symptomatic diarrhea due to Norovirus. The study involves a total of 160 Hematopoietic Stem Cell or Solid Organ transplant recipients, equal to or greater than 12 years of age with diagnosis of Norovirus who will be selected and randomly assigned (1:1) to nitazoxanide or placebo group. The study duration is 60 months and subject participation duration is 6 months. Given the safety of prolonged therapy with nitazoxanide, lack of interactions with common post-transplant medications, putative antiviral activity and prolonged duration of viral shedding we are assessing 56 doses of therapy. The longitudinal monitoring phase will provide useful information on the course of host and viral responses in subjects with chronic Norovirus infection with and without treatment. Randomization will be stratified by age group (pediatric (12 through 17 years) vs. adult (greater than or equal to 18 years)), chronicity of Norovirus-associated symptoms (acute (less than 14 days) vs. chronic (greater than or equal to 14 days)) and transplant type (solid organ (SOT)) vs. hematopoietic stem cell transplant (HSCT)). Enrolled subjects will participate in 2 phases of the study: Treatment Phase, which will include dosing with the assigned study agent for 28 days. Longitudinal Monitoring Phase which will include telephone call on Days 35, 53, 113, 173. Primary objective is 1) to assess the clinical efficacy of nitazoxanide for the management of acute and chronic Norovirus in transplant recipients.
Read the detailed description
This is a phase 2 multi-center, double-blind, placebo-controlled study of the efficacy and safety of nitazoxanide for the treatment of solid organ and hematopoietic stem cell transplant recipients with symptomatic diarrhea due to Norovirus. The study involves a total of 160 Hematopoietic Stem Cell or Solid Organ transplant recipients, equal to or greater than 12 years of age with diagnosis of Norovirus who will be selected and randomly assigned (1:1) into two treatment groups: nitazoxanide or placebo. The study duration is approximately 60 months and subject participation duration is approximately 6 months. Given the safety of prolonged therapy with nitazoxanide, lack of interactions with common post-transplant medications, putative antiviral activity and prolonged duration of viral shedding we are assessing 56 doses of therapy. The longitudinal monitoring phase will provide useful information on the course of host and viral responses in subjects with chronic Norovirus infection with and without treatment. Randomization will be stratified by age group (pediatric (12 through 17 years) vs. adult (greater than or equal to 18 years)), chronicity of Norovirus-associated symptoms (acute (less than 14 days) vs. chronic (greater than or equal to 14 days)) and transplant type (solid organ (SOT)) vs. hematopoietic stem cell transplant (HSCT)). Enrolled subjects will participate in 2 phases of the study: Treatment Phase, which will include dosing with the assigned study agent for 28 days. Longitudinal Monitoring Phase which will include telephone call on Days 35, 53, 113, 173. Primary objective is 1) to assess the clinical efficacy of nitazoxanide for the management of acute and chronic Norovirus in transplant recipients. Secondary Objectives are 1) to assess the virologic efficacy of nitazoxanide and 2) to assess the safety of nitazoxanide for the management of acute and chronic Norovirus in transplant recipients.
- Conditions
- Gastroenteritis Norovirus
- Being tested
- Nitazoxanide, Placebo
- Keywords
- Efficacy, Hematopoietic Stem Cell, Nitazoxanide, Norovirus, Prospective, Randomized, Double-Blind Study, Safety, Solid Organ Transplant Recipients, Treatment
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
NitazoxanideDrug
One 500 mg tablet twice daily with food for 56 consecutive doses
PlaceboOther
One tablet twice daily with food for 56 consecutive doses
| Study group | Role | What they receive |
|---|---|---|
| Nitazoxanide Arm | Experimental | 500 mg (one tablet) nitazoxanide by mouth twice daily with food for 56 consecutive doses. N=80 Receives: Drug: Nitazoxanide |
| Placebo Arm | Placebo comparator | Placebo (one tablet) by mouth twice daily with food for 56 consecutive doses. N=80 Receives: Other: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Time to Initial Clinical Resolution of Norovirus Symptoms
Time (in days) from randomization until the study day when clinical resolution occurred. Clinical resolution was assessed from participant's daily diaries and was defined as cessation of vomiting and no stools classified by the Bristol Stool Chart as diarrhea (Type 6 or 7) for at least 48 hours.
Measured: 48 hours through Day 180
Secondary outcomes (6)
Number of Participants Experiencing Laboratory Adverse Events (AEs)
Participants experiencing at least one new laboratory adverse event. Laboratory parameters include White Blood Cell (WBC), Hemoglobin, Platelet Count, Creatinine, Alkaline Phosphatase, Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST), Blood Urea Nitrogen (BUN), and Bilirubin. Laboratory results were considered AEs using the following thresholds : WBC greater than the upper limit of normal (ULN), hemoglobin less than the lower limit of normal (LLN), platelet count less than the LLN; creatinine greater than the ULN; alkaline phosphatase greater than the ULN; ALT greater than the ULN, AST greater than the ULN, BUN greater than or equal to the ULN, and bilirubin greater than the ULN. ULN and LLN values differed by site, sex, and age category.
Measured: Day 1 (baseline) through Day 60
Change in Viral Titer (Day 1 to Day 180)
Change in viral titer defined as the difference between the Day 180 viral titer and the Day 1 viral titer. Participants were analyzed for the viral load test type (Norovirus GII or Norovirus GI) that they tested positive for at baseline (Day 1).
Measured: Day 1 (baseline) and Day 180
Number of Participants Reporting Hospitalization
Hospitalizations included any admission to a hospital for treatment and were not reported as Serious Adverse Events (SAEs).
Measured: Day 1 (baseline) through Day 60
Number of Participants Reporting Protocol-Specified SAEs
Protocol-specified SAEs included any adverse event or suspected adverse reaction which, in the view of the investigator or sponsor, resulted in any of the following: death, life threatening adverse event, persistent or significant disability or incapacity or substantial disruption of the ability to conduct normal life function, congenital anomaly or birth defect, or an important medical event that may jeopardize the participant and require medical or surgical intervention. Hospitalizations were collected as a secondary outcome measure and were not reported as SAEs.
Measured: Day 1 (baseline) through Day 60
Number of Participants Experiencing Unsolicited Non-Serious Adverse Events
Unsolicited adverse events were defined as any non-serious clinical adverse events that were not collected as clinical outcome measures and resulted in either modification in the administration of study drug or discontinuation of the study drug.
Measured: Day 1 (baseline) through Day 60
Time to First Negative Viral Load
Time (in days) from randomization until the first study day the participant had either a negative result or a result less than the lower limit of quantitation (LLOQ) for the viral load test type (Norovirus GII or Norovirus GI) that they initially tested positive for at baseline. Participants were analyzed for the viral load test type (Norovirus GII or Norovirus GI) that they tested positive for at baseline (Day 1).
Measured: Day 1 (baseline) and Day 180
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Jan 2018
- Study start15 Oct 2018
- Primary completion24 Aug 2021
- Study completion24 Aug 2021
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Gastroenteritis NorovirusStudies of the same condition, open and under way.
- More trials run by National Institute of Allergy and Infectious Diseases (NIAID)The 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
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 31 participants (actual)
Sponsor and investigators
- Sponsor type
- US National Institutes of Health
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03395405
- Sponsor's protocol ID
- 16-0092
- Status last verified
- 25 Jun 2021
- First submitted
- 4 Jan 2018
- Last updated
- 21 May 2025
- Results posted
- Yes, on ClinicalTrials.gov
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
Publications
Boutin CA, Callegari M, Florescu D, Nguyen MH, Kaul D, Avery R, Chong P, Fisher C, Limaye AP, Clough L, Pergam SA, Green M, Michaels MG, Danziger-Isakov LA, Angarone M, Keefer L, Daud A, Lorenzo-Redondo R, Tan M, Ison MG. A phase 2 multicenter, prospective, randomized, double-blind study to assess the clinical and antiviral efficacy and safety of nitazoxanide for the treatment of norovirus in hematopoietic stem cell and solid organ transplant recipients. Am J Transplant. 2026 Sep;26(9):2169-2181. doi: 10.1016/j.ajt.2026.04.010. Epub 2026 May 22.
PubMed 42177030Shawar S, Concepcion BP. A Gut-Wrenching Infection: Norovirus in a Kidney Transplant Recipient. Clin J Am Soc Nephrol. 2023 Sep 1;18(9):1231-1233. doi: 10.2215/CJN.0000000000000243. Epub 2023 Jun 29. No abstract available.
PubMed 37382971
Study at a glance
From the registry record, last updated by the sponsor on 21 May 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 2 Multi-Center, Prospective, Randomized, Double-Blind Study to Assess the Clinical and Antiviral Efficacy and Safety of Nitazoxanide for the Treatment of Norovirus in Hematopoietic Stem Cell and Solid Organ Transplant Recipients
- ClinicalTrials.gov ID
- NCT03395405
- Acronym / sponsor ID
- 16-0092
- Conditions
- Gastroenteritis Norovirus
- Keywords
- Efficacy, Hematopoietic Stem Cell, Nitazoxanide, Norovirus, Prospective, Randomized, Double-Blind Study, Safety, Solid Organ Transplant Recipients, Treatment
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 31 participants (actual)
- Lead sponsor
- National Institute of Allergy and Infectious Diseases (NIAID)US National Institutes of Health
- Study start
- 15 Oct 2018 (actual)
- Primary completion
- 24 Aug 2021 (actual)
- Study completion
- 24 Aug 2021 (actual)
- First posted
- 10 Jan 2018 (actual)
- Results
- Posted 24 Oct 2022
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is a phase 2 multi-center, double-blind, placebo-controlled study of the efficacy and safety of nitazoxanide for the treatment of solid organ and hematopoietic stem cell transplant recipients with symptomatic diarrhea due to Norovirus. The study involves a total of 160 Hematopoietic Stem Cell or Solid Organ transplant recipients, equal to or greater than 12 years of age with diagnosis of Norovirus who will be selected and randomly assigned (1:1) to nitazoxanide or placebo group. The study duration is 60 months and subject participation duration is 6 months. Given the safety of prolonged therapy with nitazoxanide, lack of interactions with common post-transplant medications, putative antiviral activity and prolonged duration of viral shedding we are assessing 56 doses of therapy. The longitudinal monitoring phase will provide useful information on the course of host and viral responses in subjects with chronic Norovirus infection with and without treatment. Randomization will be stratified by age group (pediatric (12 through 17 years) vs. adult (greater than or equal to 18 years)), chronicity of Norovirus-associated symptoms (acute (less than 14 days) vs. chronic (greater than or equal to 14 days)) and transplant type (solid organ (SOT)) vs. hematopoietic stem cell transplant (HSCT)). Enrolled subjects will participate in 2 phases of the study: Treatment Phase, which will include dosing with the assigned study agent for 28 days. Longitudinal Monitoring Phase which will include telephone call on Days 35, 53, 113, 173. Primary objective is 1) to assess the clinical efficacy of nitazoxanide for the management of acute and chronic Norovirus in transplant recipients.
Detailed description
This is a phase 2 multi-center, double-blind, placebo-controlled study of the efficacy and safety of nitazoxanide for the treatment of solid organ and hematopoietic stem cell transplant recipients with symptomatic diarrhea due to Norovirus. The study involves a total of 160 Hematopoietic Stem Cell or Solid Organ transplant recipients, equal to or greater than 12 years of age with diagnosis of Norovirus who will be selected and randomly assigned (1:1) into two treatment groups: nitazoxanide or placebo. The study duration is approximately 60 months and subject participation duration is approximately 6 months. Given the safety of prolonged therapy with nitazoxanide, lack of interactions with common post-transplant medications, putative antiviral activity and prolonged duration of viral shedding we are assessing 56 doses of therapy. The longitudinal monitoring phase will provide useful information on the course of host and viral responses in subjects with chronic Norovirus infection with and without treatment. Randomization will be stratified by age group (pediatric (12 through 17 years) vs. adult (greater than or equal to 18 years)), chronicity of Norovirus-associated symptoms (acute (less than 14 days) vs. chronic (greater than or equal to 14 days)) and transplant type (solid organ (SOT)) vs. hematopoietic stem cell transplant (HSCT)). Enrolled subjects will participate in 2 phases of the study: Treatment Phase, which will include dosing with the assigned study agent for 28 days. Longitudinal Monitoring Phase which will include telephone call on Days 35, 53, 113, 173. Primary objective is 1) to assess the clinical efficacy of nitazoxanide for the management of acute and chronic Norovirus in transplant recipients. Secondary Objectives are 1) to assess the virologic efficacy of nitazoxanide and 2) to assess the safety of nitazoxanide for the management of acute and chronic Norovirus in transplant recipients.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, investigator)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Nitazoxanide Arm | Experimental | Drug: Nitazoxanide500 mg (one tablet) nitazoxanide by mouth twice daily with food for 56 consecutive doses. N=80 |
| Placebo Arm | Placebo comparator | Other: PlaceboPlacebo (one tablet) by mouth twice daily with food for 56 consecutive doses. N=80 |
Who may qualify
- Ages
- 12 to 99 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child, Adult, Older adult
Key inclusion criteria (11 listed)
- Male or female age > / = 12 years.
- Recipient of a solid organ or hematopoietic stem cell transplant.
- Positive test result for Norovirus within 14 days of enrollment that is obtained as part of routine clinical care using a Norovirus testing available to the site.
- Active GI symptoms (diarrhea, or vomiting) that, in the opinion of the PI, are secondary to Norovirus. Patients must have active diarrhea, which is defined as at least 3 days of Bristol 6 or 7 stools in the past 2 weeks prior to enrollment per patient report.
- Willing and able to provide written informed consent and assent before initiation of any study procedures, consistent with local IRB policy.
Key exclusion criteria (10 listed)
- Subjects meeting any of the exclusion criteria at baseline will be excluded from study participation:
- Other identified infectious causes of diarrhea at screening. Alternative diagnosis requiring treatment would be considered a co-infection; if the testing is positive for a pathogen that the PI does not feel is causing the symptoms, they may be included but the PI or his/her designee must document that the positive test is not clinically significant, does not require treatment and is not causing the symptoms making the patient eligible for enrollment.
- Any condition that would, in opinion of the Site Investigator, place the subject at an unacceptable risk of injury or render the subject unable to meet the requirements of the protocol.
- Subjects receiving oral or intravenous immunoglobulin therapy concurrently or in the 14 days prior to enrollment.
- Nitazoxanide use for any illness in the previous 30 days prior to randomization.
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 |
|---|---|---|
| NitazoxanideOne 500 mg tablet twice daily with food for 56 consecutive doses | Drug | Nitazoxanide Arm |
| PlaceboOne tablet twice daily with food for 56 consecutive doses | Other | Placebo Arm |
Primary outcome
Time to Initial Clinical Resolution of Norovirus Symptoms
Time frame: 48 hours through Day 180
Time (in days) from randomization until the study day when clinical resolution occurred. Clinical resolution was assessed from participant's daily diaries and was defined as cessation of vomiting and no stools classified by the Bristol Stool Chart as diarrhea (Type 6 or 7) for at least 48 hours.
6 secondary outcomes
Number of Participants Experiencing Laboratory Adverse Events (AEs)
Time frame: Day 1 (baseline) through Day 60
Change in Viral Titer (Day 1 to Day 180)
Time frame: Day 1 (baseline) and Day 180
Number of Participants Reporting Hospitalization
Time frame: Day 1 (baseline) through Day 60
Number of Participants Reporting Protocol-Specified SAEs
Time frame: Day 1 (baseline) through Day 60
Number of Participants Experiencing Unsolicited Non-Serious Adverse Events
Time frame: Day 1 (baseline) through Day 60
Time to First Negative Viral Load
Time frame: Day 1 (baseline) and Day 180
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 21 May 2025.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Derived from this study: PubMed 42177030Boutin CA, Callegari M, Florescu D, Nguyen MH, Kaul D, Avery R, Chong P, Fisher C, Limaye AP, Clough L, Pergam SA, Green M, Michaels MG, Danziger-Isakov LA, Angarone M, Keefer L, Daud A, Lorenzo-Redondo R, Tan M, Ison MG. A phase 2 multicenter, prospective, randomized, double-blind study to assess the clinical and antiviral efficacy and safety of nitazoxanide for the treatment of norovirus in hematopoietic stem cell and solid organ transplant recipients. Am J Transplant. 2026 Sep;26(9):2169-2181. doi: 10.1016/j.ajt.2026.04.010. Epub 2026 May 22.
- Derived from this study: PubMed 37382971Shawar S, Concepcion BP. A Gut-Wrenching Infection: Norovirus in a Kidney Transplant Recipient. Clin J Am Soc Nephrol. 2023 Sep 1;18(9):1231-1233. doi: 10.2215/CJN.0000000000000243. Epub 2023 Jun 29. No abstract available.
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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.
The record lists no contact. Use the official record to reach the sponsor.
12 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Nitazoxanide in people with Gastroenteritis Norovirus, run by National Institute of Allergy and Infectious Diseases (NIAID) at 12 sites 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 11 inclusion and 10 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: finished, as of the sponsor's last update on 21 May 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 12 sites 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. Some participants in this study may receive a placebo. 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?
Yes. Results are posted in the registry (first posted 24 Oct 2022). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
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?
Time to Initial Clinical Resolution of Norovirus Symptoms (time frame: 48 hours through Day 180). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03395405, which also lists 2 linked publications.
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 21 May 2025.