臨床研究等提出・公開システム

A Phase 2, Randomized, Multicenter, Double-blind, Placebo-controlled Study to Evaluate the Safety, Tolerability,
Pharmacokinetics, and Efficacy of Obeldesivir in Participants From Birth to < 5 Years of Age With Respiratory Syncytial Virus (RSV) Infection

Study of Obeldesivir to Treat Children With Respiratory Syncytial Virus (RSV) Infection

4

All 4 participants were assigned female at birth, of which 3 were White and 1 was Black. 1 participant was enrolled in Cohort 1 Part A Group 2 (weight at screening >= 12 kg to < 20 kg) and 3 participants were enrolled in Cohort 1 Part A Group 3 (weight at screening >= 6 kg to < 12 kg). The participant enrolled in Cohort 1 Part A Group 2 was >= 2 to < 5 years (4 years). The 3 participants enrolled in Cohort 1 Part A Group 3 were < 2 years (7, 6, and 6 months, respectively).

Of the 7 participants screened, a total of 4 participants were enrolled in the study and all of them completed the study. Three participants received ODV: the participant in Cohort 1 Part A Group 2 and 2 of the 3 participants in Cohort 1 Part A Group 3. The remaining participant in Cohort 1 Part A Group 3 received placebo. The study was terminated early after 4 participants were enrolled. The decision was not based on any safety findings. The study was planned to include Cohort 1 Part A (inclusive of 4 groups based on participant's weight), Cohort 1 Part B, and Cohort 2. Due to the early termination, only Cohort 1 Part A (Groups 2 and 3) were enrolled.

Three of 4 participants (2 ODV treated and 1 placebo treated participant) experienced at least 1 Treatment-Emergent Adverse Event (TEAE) during this study. The majority of AEs were assessed as Grade 1 or Grade 2 in severity. The placebo-treated participant in Cohort 1 Part A Group 3 experienced a Grade 3 TEAE of worsening of congestion RSV. A single SAE was reported: Grade 3 tachypnea in an ODV treated Cohort 1 Part A Group 3 participant requiring < 24 hour hospitalization. The event was considered unrelated to study drug and resolved within 1 day without changes to study treatment. All TEAEs were considered not related to the study drug, no TEAEs led to premature discontinuation of study drug or of the study, and no deaths were reported during the study.

Two participants were included in the Full Analysis Positive Set and both received ODV. The time to alleviation of targeted RSV symptoms and the time to sustained alleviation of targeted RSV symptoms was 5.4 days for the participant in Cohort 1 Part A Group 2. The other participant in Cohort 1 Part A Group 3 did not experience alleviation of targeted RSV symptoms by Day 28. The time to resolution of targeted RSV symptoms was 3.4 days for the participant in Cohort 1 Part A Group 2. The other participant in Cohort 1 Part A Group 3 did not experience resolution of targeted RSV symptoms by Day 28. Two participants were included in the Virology Analysis Set and both received ODV. At baseline, RSV nasal swab viral load was positive for the participant in Cohort 1 Part A Group 2 (4.89 log10 copies per mL) and one participant in Cohort 1 Part A Group 3 (8.45 log10 copies per mL). At Day 5, RSV nasal swab viral load decreased for both the participant in Cohort 1 Part A Group 2 (2.10 log10 copies per mL; change from baseline: 2.79 log10 copies per mL decrease) and the participant in Cohort 1 Part A Group 3 (6.33 log10 copies per mL; change from baseline: 2.12 log10 copies per mL decrease).

No new or unexpected safety findings were observed among pediatric participants exposed to ODV.

No

https://jrct.mhlw.go.jp/latest-detail/jRCT2031240735

Kamiya Makoto

Gilead Sciences, K.K.

1-9-2, Marunouchi, Chiyoda-ku, Tokyo

ClinicalTrialGSJ@gilead.com

Clinical Operations

Gilead Sciences, K.K.

1-9-2, Marunouchi, Chiyoda-ku, Tokyo

+81-3-6837-0817

JPClinicalOperations@gilead.com

Complete

April. 08, 2025

Interventional

randomized controlled trial

double blind

placebo control

parallel assignment

treatment purpose

Participants assigned male or female at birth, from birth to < 5 years of age who meet one of the following criteria, where permitted according to local law and approved nationally and by relevant institutional review board or independent ethics committee:
-Cohort 1: Infants and children from 4 weeks postnatal age, weighing >= 1.5 kg to < 40 kg
-Cohort 2: Neonates, either born at term or preterm, weighing >= 1.5 kg to < 6 kg

RSV infection diagnosis <= 3 days prior to randomization.

Negative test for influenza A/B, and SARS-CoV-2 infection <= 7 days prior to randomization.

Onset of RSV signs or symptoms <= 3 days prior to randomization.

Presence of at least 1 sign or symptom of RSV infection at screening and at randomization.

Currently requiring or expected to require hospitalization for RSV infection within 48 hours after randomization.

Documented previous infection and/or hospitalization for RSV during the current respiratory virus season.

Diagnosed with acute concurrent active systemic infections requiring treatment with systemic antiviral, antibacterial, antifungal, or antimycobacterial therapy, or with any documented respiratory viral infection (other than RSV), <= 7 days prior to randomization.

History of asthma or recurrent wheezing.

Neuromuscular disease that affects swallowing.

Cystic fibrosis.

Participants who are immunocompromised.

Alanine aminotransferase >= 5 times upper limit of normal (ULN).

Abnormal renal function.

Concurrent or previous treatment with other agents with actual or possible direct antiviral activity against RSV, received within 28 days or within 5 half-lives, whichever is longer, prior to randomization.

Received palivizumab within 100 days, or nirsevimab within 1 year, or other RSV specific monoclonal antibody within 5 half-lives of the antibody, prior to randomization.

Participant whose mother received RSV vaccination during pregnancy and who is < 1 year old prior to randomization.

Note: Other protocol defined Inclusion/Exclusion criteria may apply.

Both

RSV infection

Experimental: Obeldesivir (ODV)
-Participants will receive an age and weight appropriate ODV dose based on their cohort/group assignment.
-Administered orally

Experimental: Obeldesivir Placebo
-Participants will receive an age and weight appropriate ODV placebo dose based on their cohort/group assignment.
-Administered orally

Percentage of Participants Experiencing Treatment-emergent Adverse Events (TEAEs) Through Day 28

Percentage of Participants Experiencing Grade 3 or 4 Treatment-emergent laboratory abnormalities by Day 28

Time to Alleviation of Targeted RSV Symptoms by Day 28

Pharmacokinetic (PK) parameter AUCtau of ODV metabolite, GS-441524

PK parameter Cmax of ODV metabolite, GS-441524

PK parameter Ctrough of ODV metabolite, GS-441524

Change From Baseline in RSV Nasal Swab Viral Load at Day 5

Time to Sustained Alleviation of Targeted RSV Symptoms by Day 28

Time to Resolution of Targeted RSV Symptoms by Day 28

Assessment of Palatability and Acceptability Scores of Age-specific Formulation as Assessed by Caregiver at Days 1 and 5

Dec. 27, 2024

United States