Efficacy and Safety of Molnupiravir (MK-4482) in Hospitalized Adult Participants With COVID-19 (MK-4482-001)
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ClinicalTrials.gov Identifier: NCT04575584 |
Recruitment Status :
Terminated
(Business reasons)
First Posted : October 5, 2020
Results First Posted : August 16, 2022
Last Update Posted : January 17, 2023
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Coronavirus Disease (COVID-19) | Drug: Molnupiravir Drug: Placebo | Phase 2 Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 304 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Double (Participant, Investigator) |
Primary Purpose: | Treatment |
Official Title: | A Phase 2/3, Randomized, Placebo-Controlled, Double-Blind Clinical Study to Evaluate the Efficacy, Safety, and Pharmacokinetics of MK-4482 in Hospitalized Adults With COVID-19 |
Actual Study Start Date : | October 19, 2020 |
Actual Primary Completion Date : | August 11, 2021 |
Actual Study Completion Date : | August 11, 2021 |

Arm | Intervention/treatment |
---|---|
Experimental: Part 1: Molnupiravir 200 mg
200 mg molnupiravir administered orally every 12 hours for 5 days (10 doses total)
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Drug: Molnupiravir
Molnupiravir administered orally in capsule form every 12 hours for 5 days (10 doses total) |
Experimental: Part 1: Molnupiravir 400 mg
400 mg molnupiravir administered orally every 12 hours for 5 days (10 doses total)
|
Drug: Molnupiravir
Molnupiravir administered orally in capsule form every 12 hours for 5 days (10 doses total) |
Experimental: Part 1: Molnupiravir 800 mg
800 mg molnupiravir administered orally every 12 hours for 5 days (10 doses total)
|
Drug: Molnupiravir
Molnupiravir administered orally in capsule form every 12 hours for 5 days (10 doses total) |
Placebo Comparator: Part 1: Placebo
Placebo matching molnupiravir administered orally every 12 hours for 5 days (10 doses total)
|
Drug: Placebo
Placebo matching molnupiravir administered orally in capsule form every 12 hours for 5 days (10 doses total) |
Experimental: Part 2: Molnupiravir
Molnupiravir (dose to be selected) administered orally every 12 hours for 5 days (10 doses total)
|
Drug: Molnupiravir
Molnupiravir administered orally in capsule form every 12 hours for 5 days (10 doses total) |
Placebo Comparator: Part 2: Placebo
Placebo matching molnupiravir administered orally every 12 hours for 5 days (10 doses total)
|
Drug: Placebo
Placebo matching molnupiravir administered orally in capsule form every 12 hours for 5 days (10 doses total) |
- Time-to-sustained Recovery [ Time Frame: Up to 29 days ]The median time to sustained recovery is reported. Sustained recovery is defined as 1) the participant is alive and not hospitalized; or 2) the participant is alive and medically ready for discharge as determined by the investigator.
- Number of Participants With an Adverse Event (AE) [ Time Frame: Up to 19 days (during treatment and 14-day follow-up) ]The number of participants with at least 1 AE is presented. An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention.
- Number of Participants Who Discontinued Study Intervention Due to an AE [ Time Frame: Up to 5 days ]The number of participants discontinuing from study treatment due to an AE is presented. An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention.
- Number of Participants With All-cause Mortality [ Time Frame: Up to 29 days ]The number of participants with all-cause mortality through Day 29 is presented. All-cause mortality is defined as death due to any cause. Any participants with an unknown survival status at Day 29 were imputed as deceased.
- Odds of a More Favorable Response on Pulmonary Ordinal Outcome Score on Day 3 [ Time Frame: Day 3 ]Pulmonary score is a score on an ordinal scale which focuses on respiratory sequalae based on oxygen requirements using 7 mutually exclusive categories. The score ranges from 1 ("can independently undertake personal usual activities with minimal or no symptoms") to 7 ("death") with a higher score indicating more severe respiratory sequalae. The number of participants at each score category is presented.
- Odds of a More Favorable Response on Pulmonary Ordinal Outcome Score on End of Treatment (EOT [Day 5]) [ Time Frame: EOT (Day 5) ]Pulmonary score is a score on an ordinal scale which focuses on respiratory sequalae based on oxygen requirements using 7 mutually exclusive categories. The score ranges from 1 ("can independently undertake personal usual activities with minimal or no symptoms") to 7 ("death") with a higher score indicating more severe respiratory sequalae. The number of participants at each score category is presented.
- Odds of a More Favorable Response on Pulmonary Ordinal Outcome Score on Day 10 [ Time Frame: Day 10 ]Pulmonary score is a score on an ordinal scale which focuses on respiratory sequalae based on oxygen requirements using 7 mutually exclusive categories. The score ranges from 1 ("can independently undertake personal usual activities with minimal or no symptoms") to 7 ("death") with a higher score indicating more severe respiratory sequalae. The number of participants at each score category is presented.
- Odds of a More Favorable Response on Pulmonary Ordinal Outcome Score on Day 15 [ Time Frame: Day 15 ]Pulmonary score is a score on an ordinal scale which focuses on respiratory sequalae based on oxygen requirements using 7 mutually exclusive categories. The score ranges from 1 ("can independently undertake personal usual activities with minimal or no symptoms") to 7 ("death") with a higher score indicating more severe respiratory sequalae. The number of participants at each score category is presented.
- Odds of a More Favorable Response on Pulmonary Ordinal Outcome Score on Day 29 [ Time Frame: Day 29 ]Pulmonary score is a score on an ordinal scale which focuses on respiratory sequalae based on oxygen requirements using 7 mutually exclusive categories. The score ranges from 1 ("can independently undertake personal usual activities with minimal or no symptoms") to 7 ("death") with a higher score indicating more severe respiratory sequalae. The number of participants at each score category is presented.
- Odds of a More Favorable Response on Pulmonary+ Ordinal Outcome Score on Day 3 [ Time Frame: Day 3 ]Pulmonary+ score is a score on an ordinal scale which is a 7-category assessment that captures the range of disease severity in hospitalized participants, including coagulation-related complications and respiratory dysfunction. The score ranges from 1 ("can independently undertake personal usual activities with minimal or no symptoms") to 7 ("death") with a higher score indicating more severe respiratory sequalae. The number of participants at each score category is presented.
- Odds of a More Favorable Response on Pulmonary+ Ordinal Outcome Score on EOT (Day 5) [ Time Frame: EOT (Day 5) ]Pulmonary+ score is a score on an ordinal scale which is a 7-category assessment that captures the range of disease severity in hospitalized participants, including coagulation-related complications and respiratory dysfunction. The score ranges from 1 ("can independently undertake personal usual activities with minimal or no symptoms") to 7 ("death") with a higher score indicating more severe respiratory sequalae. The number of participants at each score category is presented.
- Odds of a More Favorable Response on Pulmonary+ Ordinal Outcome Score on Day 10 [ Time Frame: Day 10 ]Pulmonary+ score is a score on an ordinal scale which is a 7-category assessment that captures the range of disease severity in hospitalized participants, including coagulation-related complications and respiratory dysfunction. The score ranges from 1 ("can independently undertake personal usual activities with minimal or no symptoms") to 7 ("death") with a higher score indicating more severe respiratory sequalae. The number of participants at each score category is presented.
- Odds of a More Favorable Response on Pulmonary+ Ordinal Outcome Score on Day 15 [ Time Frame: Day 15 ]Pulmonary+ score is a score on an ordinal scale which is a 7-category assessment that captures the range of disease severity in hospitalized participants, including coagulation-related complications and respiratory dysfunction. The score ranges from 1 ("can independently undertake personal usual activities with minimal or no symptoms") to 7 ("death") with a higher score indicating more severe respiratory sequalae. The number of participants at each score category is presented.
- Odds of a More Favorable Response on Pulmonary+ Ordinal Outcome Score on Day 29 [ Time Frame: Day 29 ]Pulmonary+ score is a score on an ordinal scale which is a 7-category assessment that captures the range of disease severity in hospitalized participants, including coagulation-related complications and respiratory dysfunction. The score ranges from 1 ("can independently undertake personal usual activities with minimal or no symptoms") to 7 ("death") with a higher score indicating more severe respiratory sequalae. The number of participants at each score category is presented.
- Odds of a More Favorable Response in the Clinical Risk of Mortality Category From the National Early Warning Score [ Time Frame: EOT (Day 5) ]The National Early Warning Score (Royal College of Physicians, 2012) assesses a participant's degree of illness as assessed by clinical risk prediction categories based on a set of vital sign measurements. There are 7 physiological parameters: respiration rate, oxygen saturation, supplemental oxygen, systolic blood pressure, pulse rate, level of consciousness, and temperature. A score of 0 to 3 was allocated to each parameter except supplemental oxygen use (score of 0 [no] or 2 [yes]) and level of consciousness (score of 0 or 3 with 0 = normal health condition and 3 = worst health condition). All scores were summed to get an aggregate score. Aggregate NEWS score ranged from 0 to 19, with higher scores meaning more severity/higher risk: low risk (score 0 to 4); low to medium risk (score of 3 in any individual parameter); medium risk (score 5 to 6); high risk (score 7 to 19). The number of participants at each aggregate risk category is presented.
- Odds of a More Favorable Response on WHO 11-point Ordinal Outcomes Score on a Scale on Day 3 [ Time Frame: Day 3 ]The World Health Organization (WHO) outcome scale is an 11-point ordinal score that categorizes clinical progression. Score ranges from 0 ("uninfected") to 10 ("dead") with higher score indicating clinical progression. The number of participants at each score category is presented.
- Odds of a More Favorable Response on WHO 11-point Ordinal Outcomes Score on a Scale on EOT (Day 5) [ Time Frame: EOT (Day 5) ]The World Health Organization (WHO) outcome scale is an 11-point ordinal score that categorizes clinical progression. Score ranges from 0 ("uninfected") to 10 ("dead") with higher score indicating clinical progression. The number of participants at each score category is presented.
- Odds of a More Favorable Response on WHO 11-point Ordinal Outcomes Score on a Scale on Day 10 [ Time Frame: Day 10 ]The World Health Organization (WHO) outcome scale is an 11-point ordinal score that categorizes clinical progression. Score ranges from 0 ("uninfected") to 10 ("dead") with higher score indicating clinical progression. The number of participants at each score category is presented.
- Odds of a More Favorable Response on WHO 11-point Ordinal Outcomes Score on a Scale on Day 15 [ Time Frame: Day 15 ]The World Health Organization (WHO) outcome scale is an 11-point ordinal score that categorizes clinical progression. Score ranges from 0 ("uninfected") to 10 ("dead") with higher score indicating clinical progression. The number of participants at each score category is presented.
- Odds of a More Favorable Response on WHO 11-point Ordinal Outcomes Score on a Scale on Day 29 [ Time Frame: Day 29 ]The World Health Organization (WHO) outcome scale is an 11-point ordinal score that categorizes clinical progression. Score ranges from 0 ("uninfected") to 10 ("dead") with higher score indicating clinical progression. The number of participants at each score category is presented.

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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:
- Has documentation of polymerase chain reaction (PCR)-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection with sample collection ≤ 10 days prior to the day of randomization. PCR is the preferred method; however other diagnostic methods are allowed if authorized by use in the country
- Had initial onset of signs/symptoms attributable to COVID-19 for ≤10 days prior to the day of randomization and ≥1 sign/symptom attributable to COVID-19 present at randomization
- Requires medical care in the hospital for ongoing clinical manifestations of COVID-19 (not just for public health or quarantine purposes)
- Has mild, moderate, or severe COVID-19
- Is willing and able to take oral medication
- Males agree to the following during the intervention period and for at least 90 days after the last dose of study intervention: Refrain from donating sperm; and either abstain from heterosexual intercourse as their preferred and usual lifestyle (abstinent on a long term and persistent basis) and agree to remain abstinent; or must agree to use contraception
- Females are not pregnant or breastfeeding, and at least one of the following conditions applies: Is not a woman of child bearing potential (WOCBP); or is a WOCBP and using a contraceptive method that is highly effective (a low user dependency method OR a user dependent method in combination with barrier method), or be abstinent from heterosexual intercourse as their preferred and usual lifestyle (abstinent on a long-term and persistent basis) for 28 days from the start of study intervention; a WOCBP must have a negative highly sensitive pregnancy test (serum test is required) within 24 hours before the first dose of study intervention
Exclusion Criteria:
- Has critical COVID-19 with any of the following: respiratory failure (including endotracheal intubation and mechanical ventilation, oxygen delivered by high-flow nasal cannula (flow rates >20L/min with fraction of delivered oxygen ≥ 0.5), noninvasive positive pressure ventilation, or extracorporeal membrane oxygenation (ECMO))
- Is on dialysis or has reduced estimated glomerular filtration rate (eGFR) <30 mL/min/1.73m^2 by the Modification of Diet in Renal Disease (MDRD) equation
- Has any of the following conditions: human immunodeficiency virus (HIV) with a recent viral load >50 copies/mL or cluster of differentiation 4 (CD4) <200 cell/mm^3; chemotherapy required within 6 weeks before randomization; a neutrophilic granulocyte absolute count <500/mm^3; autologous or allogeneic hematopoietic stem cell transplant recipient
- Has history of Hepatitis B or Hepatitis C infection with any of the following: 1) cirrhosis 2) end-stage liver disease 3) hepatocellular carcinoma 4) aspartate aminotransferase (AST) and/or alanine aminotransferase (ALT) > 3 times the upper limit of normal at screening
- Has a history of acute pancreatitis within 3 months prior to randomization or a history of chronic pancreatitis
- Is taking or is anticipated to require any prohibited therapies
- Is unwilling to abstain from participating in another interventional clinical trial through Day 29 with an investigational compound or device, including those for COVID-19 therapeutics
- Is anticipated to require transfer to a non-study hospital within 72 hours
- Has a baseline heart rate of < 50 beats per minute at rest
- Has a platelet count <100,000/μL or received a platelet transfusion in the 5 days prior to randomization
- Has hypersensitivity or other contraindication to any of the components of the study interventions as determined by the investigator
- Has any condition for which, in the opinion of the investigator, participation would not be in the best interest of the participant or that could prevent, limit, or confound the protocol-specified assessments including but not limited to: participants who are not expected to survive longer than 48 hours after randomization or participants who are expected to require mechanical ventilation within 48 hours after randomization or participants with a recent history of mechanical ventilation or participants with conditions that could limit gastrointestinal absorption of capsule contents

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): NCT04575584

Study Director: | Medical Director | Merck Sharp & Dohme LLC |
Documents provided by Merck Sharp & Dohme LLC:
Responsible Party: | Merck Sharp & Dohme LLC |
ClinicalTrials.gov Identifier: | NCT04575584 |
Other Study ID Numbers: |
4482-001 MK-4482-001 ( Other Identifier: Merck ) PHRR201210-003189 ( Registry Identifier: PHRR ) jRCT2031200404 ( Registry Identifier: jRCT ) 2020-003367-26 ( EudraCT Number ) |
First Posted: | October 5, 2020 Key Record Dates |
Results First Posted: | August 16, 2022 |
Last Update Posted: | January 17, 2023 |
Last Verified: | January 2023 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Yes |
Plan Description: | http://engagezone.msd.com/doc/ProcedureAccessClinicalTrialData.pdf |
URL: | http://engagezone.msd.com/ds_documentation.php |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Molnupiravir COVID-19 Pneumonia, Viral Pneumonia Respiratory Tract Infections Infections Virus Diseases Coronavirus Infections |
Coronaviridae Infections Nidovirales Infections RNA Virus Infections Lung Diseases Respiratory Tract Diseases Antiviral Agents Anti-Infective Agents |