Safety and Efficacy of Niclosamide in Patients With COVID-19 With Gastrointestinal Infection (RESERVOIR)
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ClinicalTrials.gov Identifier: NCT04858425 |
Recruitment Status :
Active, not recruiting
First Posted : April 26, 2021
Last Update Posted : February 2, 2023
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Covid19 | Drug: Niclosamide Drug: Placebo | Phase 2 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 166 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor) |
Primary Purpose: | Treatment |
Official Title: | A 2-Part, 2-Arm, Phase 2, Randomized, Double-Blind, Placebo-Controlled Study on the Safety and Efficacy of Niclosamide in Patients With COVID-19 With Gastrointestinal Infection |
Actual Study Start Date : | April 30, 2021 |
Actual Primary Completion Date : | March 17, 2022 |
Estimated Study Completion Date : | March 2023 |

Arm | Intervention/treatment |
---|---|
Experimental: Niclosamide
Niclosamide tablets 400 mg 3 times daily for 14 days
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Drug: Niclosamide
Niclosamide tablets 400 mg 3 times daily for 14 days |
Placebo Comparator: Placebo
Matching placebo tablets 3 times daily for 14 days
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Drug: Placebo
Matched placebo tablets 400 mg 3 times daily for 14 days |
- SAEs [ Time Frame: Day 1 to 6 weeks ]Serious adverse event (SAE) coded by System Organ Class (SOC) and Preferred Term (PT), using the Medical Dictionary for Regulatory Activities (MedDRA).
- TEAE [ Time Frame: Day 1 to 6 weeks ]Proportion of patients with Treatment Emergent Adverse Events (TEAE) leading to study drug discontinuation.
- Safety Laboratory Tests including CBC, BUN, blood sugar, electrolytes [ Time Frame: Day 1 to Day 43 ]Change in safety laboratory tests, including CBC, BUN, blood sugar, electrolytes, alkaline phosphatase, AST, ALT, LDH, total bilirubin, serum creatinine, from baseline to 6 weeks, the number of subjects with values low, normal, and high compared to the normal ranges pretreatment versus post-treatment will be provided.
- Fecal RNA virus Clearance [ Time Frame: Day 1 to 6 weeks ]Time to fecal viral RNA clearance (stool sample) assessed by RT-qPCR in the niclosamide arm compared to the placebo arm.
- Clinical Severity Score [ Time Frame: Day 1 to 6 weeks ]Proportion of patients with each clinical severity score as recommended by the World Health Organization (WHO) for COVID-19 studies by study visit;
- Time to Resolution of Diarrhea [ Time Frame: Day 1 to 6 weeks ]Time from the first dose of study treatment to the last loose or watery stool in patients with loose or watery stool (Bristol Stool Scale Types 5-7).

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Part 1 only, patients with a primary diagnosis of COVID-19, with or without pneumonia, who agree to be monitored daily for at least 7 days after randomization and who accept continuing to be assessed for the study procedures.
- Part 2 only, patients with a primary diagnosis of COVID-19, with or without pneumonia.
Exclusion Criteria:
- At the time of randomization, patients who require intensive care unit (ICU) admission or patients with severe respiratory insufficiency who require mechanical ventilation or with rapid worsening of respiratory function leading to expectation for mechanical ventilation or ICU admission.
- Evidence of rapid clinical deterioration or existence of any life-threatening co-morbidity or any other medical condition that, in the opinion of the investigator, makes the patient unsuitable for inclusion.
- Patients who, at the time of enrollment, are not in a clinical condition compatible with the oral administration of the study drug.

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): NCT04858425

Responsible Party: | First Wave Bio, Inc. |
ClinicalTrials.gov Identifier: | NCT04858425 |
Other Study ID Numbers: |
AZ-NICL-COV-1 |
First Posted: | April 26, 2021 Key Record Dates |
Last Update Posted: | February 2, 2023 |
Last Verified: | August 2022 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
SARS-CoV-2 Covid Covid19 Diarrhea Covid19 GI Infection |
COVID-19 Niclosamide Infections Respiratory Tract Infections Pneumonia, Viral Pneumonia Virus Diseases Coronavirus Infections Coronaviridae Infections Nidovirales Infections |
RNA Virus Infections Lung Diseases Respiratory Tract Diseases Anticestodal Agents Antiplatyhelmintic Agents Anthelmintics Antiparasitic Agents Anti-Infective Agents Antinematodal Agents |