Percentage of Participants Experiencing Treatment Emergent Adverse Events (TEAEs)
An adverse event (AE) was any untoward medical occurrence in a participant administered a study drug, which did not necessarily have a causal relationship with the treatment. AE was therefore any unfavorable and/or unintended sign, symptom, or disease temporally associated with the use of the study drug, whether or not considered related to the study drug. TEAEs: AE with an onset date on or after the study drug start date and no later than 30 days after study drug stop date; or any AE leading to study drug discontinuation.
Percentage of Participants With Treatment-Emergent Laboratory Abnormalities as Per Severity Grade
Treatment-emergent laboratory abnormalities were graded using the Division of AIDS (DAIDS) Table for Grading the Severity of Adult and Pediatric Adverse Events, Version 2.1 July 2017. Laboratory abnormalities were graded as Grade 1 (mild), Grade 2 (moderate), Grade 3 (severe), Grade 4 (life-threatening). Percentage of participants with any severity grade were reported.
Percentage of Participants With Treatment-Emergent Adverse Events Leading to Study Treatment Discontinuation
Number of Participants With All-Cause Medically Attended Visits (MAVs) or Death by Day 28
The composite outcome of all-cause MAVs (medical visits attended in person by the participant and a health care professional) or all-cause death by Study Day 28 were estimated using Kaplan-Meier methods by treatment group.
Number of Participants With COVID-19 Related MAVs or Death by Day 28
The composite outcome of COVID-19 related MAVs (medical visits attended in person by the participant and a health care professional) or all-cause death by Study Day 28 were estimated using Kaplan-Meier methods by treatment group.
Number of Participants With Hospitalization by Day 28
The composite of all-cause hospitalization was estimated using Kaplan-Meier methods by treatment group.
Pharmacokinetic (PK) Parameter: AUC0-24h of Remdesivir (RDV) and Its Metabolites (GS-441524 and GS-704277) in Parts A and B
AUC0-24h was defined as the concentration of drug over time between time 0 to time 24 hours. Time Frame for PK samples: Sparse PK (all participants): Day 1 (end of nebulization, and optional 2-hour post nebulization), and Day 3 (predose and end of nebulization); Intensive PK (Up to 6 participants/group in Part A & Part B): Day 1 and an additional sample at Day 3 or Day 5 at the following time points: 0 (predose), 0.25, 0.5, 0.75, 1, 1.5, 2, 4, and 24 hours post end of nebulization.
PK Parameter: AUClast of RDV and Its Metabolites (GS-441524 and GS-704277) in Parts A and B
AUClast was defined as the concentration of drug from time zero to the last observable concentration.Time Frame for PK samples: Sparse PK (all participants): Day 1 (end of nebulization, and optional 2-hour post nebulization), and Day 3 (predose and end of nebulization); Intensive PK (Up to 6 participants/group in Part A & Part B): Day 1 and an additional sample at Day 3 or Day 5 at the following time points: 0 (predose), 0.25, 0.5, 0.75, 1, 1.5, 2, 4, and 24 hours post end of nebulization.
PK Parameter: CLss/F of RDV and Its Metabolites (GS-441524 and GS-704277) in Parts A and B
CLss/F was defined as apparent oral clearance at steady state after administration of the drug. CLss/F = Dose/AUCtau, where "Dose" is the dose of the drug. Time Frame for PK samples: Sparse PK (all participants): Day 1 (end of nebulization, and optional 2-hour post nebulization), and Day 3 (predose and end of nebulization); Intensive PK (Up to 6 participants/group in Part A & Part B): Day 1 and an additional sample at Day 3 or Day 5 at the following time points: 0 (predose), 0.25, 0.5, 0.75, 1, 1.5, 2, 4, and 24 hours post end of nebulization.
PK Parameter: t1/2 of RDV and Its Metabolites (GS-441524 and GS-704277) in Parts A and B
t1/2 was defined as the estimate of the terminal elimination half-life of the drug. Time Frame for PK samples: Sparse PK (all participants): Day 1 (end of nebulization, and optional 2-hour post nebulization), and Day 3 (predose and end of nebulization); Intensive PK (Up to 6 participants/group in Part A & Part B): Day 1 and an additional sample at Day 3 or Day 5 at the following time points: 0 (predose), 0.25, 0.5, 0.75, 1, 1.5, 2, 4, and 24 hours post end of nebulization.
PK Parameter: Vz/F of RDV and Its Metabolites (GS-441524 and GS-704277) in Parts A and B
Vz/F was defined as the apparent volume of distribution of the drug. Time Frame for PK samples: Sparse PK (all participants): Day 1 (end of nebulization, and optional 2-hour post nebulization), and Day 3 (predose and end of nebulization); Intensive PK (Up to 6 participants/group in Part A & Part B): Day 1 and an additional sample at Day 3 or Day 5 at the following time points: 0 (predose), 0.25, 0.5, 0.75, 1, 1.5, 2, 4, and 24 hours post end of nebulization.
PK Parameter: Cmax of RDV and Its Metabolites (GS-441524 and GS-704277) in Parts A and B
Cmax was defined as the maximum observed concentration of drug.Time Frame for PK samples: Sparse PK (all participants): Day 1 (end of nebulization, and optional 2-hour post nebulization), and Day 3 (predose and end of nebulization); Intensive PK (Up to 6 participants/group in Part A & Part B): Day 1 and an additional sample at Day 3 or Day 5 at the following time points: 0 (predose), 0.25, 0.5, 0.75, 1, 1.5, 2, 4, and 24 hours post end of nebulization.
PK Parameter: Tmax of RDV and Its Metabolites (GS-441524 and GS-704277) in Parts A and B
Tmax was defined as the time (observed time point) of Cmax. Time Frame for PK samples: Sparse PK (all participants): Day 1 (end of nebulization, and optional 2-hour post nebulization), and Day 3 (predose and end of nebulization); Intensive PK (Up to 6 participants/group in Part A & Part B): Day 1 and an additional sample at Day 3 or Day 5 at the following time points: 0 (predose), 0.25, 0.5, 0.75, 1, 1.5, 2, 4, and 24 hours post end of nebulization.
PK Parameter: Clast of RDV and Its Metabolites (GS-441524 and GS-704277) in Parts A and B
Clast was defined as the last observable concentration of drug. Time Frame for PK samples: Sparse PK (all participants): Day 1 (end of nebulization, and optional 2-hour post nebulization), and Day 3 (predose and end of nebulization); Intensive PK (Up to 6 participants/group in Part A & Part B): Day 1 and an additional sample at Day 3 or Day 5 at the following time points: 0 (predose), 0.25, 0.5, 0.75, 1, 1.5, 2, 4, and 24 hours post end of nebulization.
PK Parameter: Tlast of RDV and Its Metabolites (GS-441524 and GS-704277) in Parts A and B
Tlast was defined as the time (observed time point) of Clast. Time Frame for PK samples: Sparse PK (all participants): Day 1 (end of nebulization, and optional 2-hour post nebulization), and Day 3 (predose and end of nebulization); Intensive PK (Up to 6 participants/group in Part A & Part B): Day 1 and an additional sample at Day 3 or Day 5 at the following time points: 0 (predose), 0.25, 0.5, 0.75, 1, 1.5, 2, 4, and 24 hours post end of nebulization.
PK Parameter: AUCtau of RDV and Its Metabolites (GS-441524 and GS-704277) in Parts A and B
AUCtau is defined as concentration of drug over time (the area under the concentration versus time curve over the dosing interval). Time Frame for PK samples: Sparse PK (all participants): Day 1 (end of nebulization, and optional 2-hour post nebulization), and Day 3 (predose and end of nebulization); Intensive PK (Up to 6 participants/group in Part A & Part B): Day 1 and an additional sample at Day 3 or Day 5 at the following time points: 0 (predose), 0.25, 0.5, 0.75, 1, 1.5, 2, 4, and 24 hours post end of nebulization.
PK Parameter: λz of RDV and Its Metabolites (GS-441524 and GS-704277) in Parts A and B
λz was defined as the terminal elimination rate constant, estimated by linear regression of the terminal elimination phase of the log plasma concentration of drug versus time curve of the drug. Time Frame for PK samples: Sparse PK (all participants): Day 1 (end of nebulization, and optional 2-hour post nebulization), and Day 3 (predose and end of nebulization); Intensive PK (Up to 6 participants/group in Part A & Part B): Day 1 and an additional sample at Day 3 or Day 5 at the following time points: 0 (predose), 0.25, 0.5, 0.75, 1, 1.5, 2, 4, and 24 hours post end of nebulization.
PK Parameter: Ctau of RDV and Its Metabolites (GS-441524 and GS-704277) in Parts A and B
Ctau was defined as the observed drug concentration at the end of the dosing interval. Time Frame for PK samples: Sparse PK (all participants): Day 1 (end of nebulization, and optional 2-hour post nebulization), and Day 3 (predose and end of nebulization); Intensive PK (Up to 6 participants/group in Part A & Part B): Day 1 and an additional sample at Day 3 or Day 5 at the following time points: 0 (predose), 0.25, 0.5, 0.75, 1, 1.5, 2, 4, and 24 hours post end of nebulization.
Change in Nasopharyngeal SARS-CoV-2 Viral Load From Baseline to Day 5
Change in Oropharyngeal SARS-CoV-2 Viral Load From Baseline to Day 5
Change in Saliva SARS-CoV-2 Viral Load From Baseline to Day 5
Change in Nasopharyngeal SARS-CoV-2 Viral Load From Baseline to Day 7
Change in Oropharyngeal SARS-CoV-2 Viral Load From Baseline to Day 7
Change in Saliva SARS-CoV-2 Viral Load From Baseline to Day 7
Change in Nasopharyngeal SARS-CoV-2 Viral Load From Baseline to Day 14 in Parts A and B
Change in Oropharyngeal SARS-CoV-2 Viral Load From Baseline to Day 14 in Parts A and B
Change in Saliva SARS-CoV-2 Viral Load From Baseline to Day 14 in Parts A and B
Time to Negative Nasopharyngeal SARS-CoV-2 Polymerase Chain Reaction (PCR)
The time to negative nasopharyngeal SARS-CoV-2 PCR was defined as the number of days to first confirmed negative (first date of two consecutive dates achieving negative result) using nasopharyngeal sample. Time to negative nasopharyngeal SARS-CoV-2 PCR was calculated using Kaplan-Meier estimates.
Time to Negative Oropharyngeal SARS-CoV-2 Polymerase Chain Reaction (PCR)
The time to negative oropharyngeal SARS-CoV-2 PCR was defined as the number of days to first confirmed negative (first date of two consecutive dates achieving negative result) using an oropharyngeal sample. Time to negative oropharyngeal SARS-CoV-2 PCR was calculated using Kaplan-Meier estimates.
Time to Negative Saliva SARS-CoV-2 Polymerase Chain Reaction (PCR)
The time to saliva SARS-CoV-2 PCR was defined as the number of days to first confirmed negative (first date of two consecutive dates achieving negative result) using saliva sample. Time to negative saliva SARS-CoV-2 PCR was calculated using Kaplan-Meier estimates.
Time to Alleviation (Mild or Absent) of Baseline COVID-19 Symptoms as Reported on the COVID-19 Adapted InFLUenza Patient-Reported Outcome (FLU-PRO©) Questionnaire in Part C
The InFLUenza Patient-Reported Outcome (FLU-PRO©) is a 32-item patient-reported outcome questionnaire that assesses the severity of symptoms of influenza and influenza-like illness across six body systems. An additional two items can be added to assess changes in taste or smell, if the instrument is used to quantify symptoms in studies of COVID-19. Each domain scores ranges from 0 (symptom-free) to 4 (very severe symptoms). Higher scores on this scale represent higher disease severity. Alleviation is defined as symptom scores as 2 or higher at baseline are scored as 0 (absent) or 1 (mild) at post-baseline, and symptoms scored as 1 at baseline are scored as 0 at post-baseline, and for two consecutive days. Time to alleviation was calculated using Kaplan-Meier estimates.