Study of Obeldesivir in Children and Adolescents With COVID-19

Study Overview
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Brief Summary
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The goal of this clinical study is to learn more about the safety and tolerability of obeldesivir (ODV) in children and adolescents with coronavirus disease 2019 (COVID-19). The primary objectives are to evaluate the plasma pharmacokinetics (PK), safety and tolerability of ODV in pediatric participants with COVID-19.

Detailed Description
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Pediatric participants will be enrolled as follows: Cohort 1: ≥ 6 years to < 18 years and weight ≥ 40 kg Cohort 2: ≥ 6 years to < 18 years and weight ≥ 20 kg to < 40 kg Cohort 3: ≥ 2 years to < 18 years and weight ≥ 12 kg to < 20 kg Cohort 4: ≥ 28 days to < 18 years and weight ≥ 3 kg to < 12 kg Cohort 5: ≥ 14 days to < 28 days of age, gestational age (GA) ≥ 37 weeks and weight ≥ 2.5 kg Cohort 6: 0 days to < 14 days of age, GA ≥ 37 weeks and birth weight ≥ 2.5 kg Cohort 7: 0 days to < 56 days of age, GA < 37 weeks and birth weight ≥ 1.5 kg

Official Title
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A Phase 2/3 Single-Arm, Open-label Study to Evaluate the Safety, Pharmacokinetics and Efficacy of Obeldesivir in Pediatric Participants With COVID-19

Conditions
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COVID-19

Intervention / Treatment
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* Drug: Obeldesivir


Participation Criteria
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Eligibility Criteria
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Key Inclusion Criteria: Individual or legal guardian willing and able to provide written informed consent prior to performing study procedures. Individuals will provide assent, if possible, in accordance with local requirements and investigator's discretion. Aged < 18 years who meet one of the following weight criteria and gestational age (GA) criteria where applicable: Cohort 1: ≥ 6 years to < 18 years and weight ≥ 40 kg Cohort 2: ≥ 6 years to < 18 years and weight ≥ 20 kg to < 40 kg Cohort 3: ≥ 2 years to < 18 years and weight ≥ 12 kg to < 20 kg Cohort 4: ≥ 28 days to < 18 years and weight ≥ 3 kg to < 12 kg Cohort 5: ≥ 14 days to < 28 days of age, GA ≥ 37 weeks and weight ≥ 2.5 kg Cohort 6: 0 days to < 14 days of age, GA ≥ 37 weeks and birth weight ≥ 2.5 kg Cohort 7: 0 days to < 56 days of age, GA < 37 weeks and birth weight ≥ 1.5 kg Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection confirmed by polymerase chain reaction (PCR) or an alternative molecular diagnostic assay ≤ 5 days before screening. Initial onset of coronavirus disease 2019 (COVID-19) signs/symptoms ≤ 5 days before screening with ≥ 1 sign/symptom such as fever, cough, fatigue, shortness of breath, sore throat, headache, myalgia/arthralgia present at screening. Presence of ≥ 1 characteristic or underlying medical condition associated with an increased risk of developing severe illness due to COVID-19. Key Exclusion Criteria: Anticipated access to and use of authorized or approved COVID-19 therapies during the current COVID-19 illness < 5 days after screening (therapies including but not limited to nirmatrelvir/ritonavir, molnupiravir, intravenous RDV, monoclonal antibodies). Vaccination for SARS-CoV-2 or self-reported history of SARS-CoV-2 infection < 4 months prior to screening. Received any approved, authorized, or investigational direct acting antiviral drug against SARS-CoV-2 for the treatment of COVID-19 < 28 days or < 5 half-lives, whichever is longer, before enrollment. Note: Other protocol defined Inclusion/Exclusion criteria may apply.

Ages Eligible for Study
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Maximum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Obeldesivir (ODV)<br>Participants will receive ODV for 5 days. The ODV dose to be administered in each cohort based on age and weight as follows: Cohort 1: ODV, tablets, 350 mg twice daily (BID) Cohort 2: ODV, tablets, 175 mg BID Cohorts 3-7: ODV doses will be determined based on available PK data. | Drug: Obeldesivir<br>* Tablet administered orally with or without food<br>* Other names: GS-5245;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pharmacokinetic (PK) Parameter: AUC0-12 of Obeldesivir (ODV) Metabolite, GS-441524 | AUC0-12 is defined as the area under the concentration versus time curve from time 0 to time 12 hours. | Cohorts 1 and 2: Day 3 and 5 | 
| PK Parameter: Cmax of ODV Metabolite, GS-441524 | Cmax is defined as maximum observed concentration of drug. | Cohorts 1 and 2: Day 3 and 5 | 
| PK Parameter: Ctrough of ODV Metabolite, GS-441524 | Ctrough is defined as concentration at the end of the dosing interval. | Cohorts 1 and 2: Day 3 and 5 | 
| Percentage of Participants Experiencing Treatment-Emergent Adverse Events (AEs) by Day 35 |  | First dose date up to Day 5 plus 30 days | 
| Percentage of Participants Experiencing Treatment-Emergent Laboratory Abnormalities by Day 35 |  | First dose date up to Day 5 plus 30 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to Sustained Alleviation of Targeted Coronavirus Disease 2019 (COVID-19) Symptoms by Day 35 |  | First dose date up to Day 35 | 
| Change from Baseline in Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Viral Load at Day 5 |  | Baseline, Day 5 | 
| Proportion of Participants Who Require Supplemental Oxygen Support by Day 35 |  | First dose date up to Day 35 | 
| Percentage of Participants With Palatability and Acceptability for Each Formulation as Measured by Questionnaire Scores | Palatability and acceptability assessed by a numeric response between numbers 1-5. Higher scores indicate better palatability and acceptability. | Day 5 | 
| Proportion of Participants with Concomitant Use of Medications Other Than Remdesivir (RDV) and Obeldesivir (ODV) for Treatment of COVID-19 by Day 35 |  | First dose date up to Day 35 | 
| Proportion of Participants with COVID-19-Related Hospitalization or All-Cause Death by Day 35 |  | First dose date up to Day 35 |