THAI-CARES RSV Study is a Phase II, open-label, multicenter, randomized controlled trial with a two-arm, parallel-group design. The study aims to assess the safety, efficacy, and acceptability of a five-day course of Remdesivir (VEKLURY®) in children under two years of age who are hospitalized with confirmed respiratory syncytial virus (RSV) infection, as determined by either a rapid antigen test or RT-PCR. The primary objectives include evaluating the treatment's safety profile, its ability to significantly reduce RSV replication, and its overall acceptance in this patient population.

An overall target of 120 participants will be involved in the study. Eligible participants will be randomized (1:1) to receive ARM 1: Standard of care alone (control arm). ARM 2: Remdesivir in combination with the standard of care. Remdesivir will be administered by intravenous infusion every 24 hours for five (5) consecutive days. Each participant will be followed during hospitalization plus 7-10 days after Day 6* for final visit.

Inclusion Criteria:

• Signed informed consent from parents/caregivers

• Aged 0 to <2 years

• Weighing at least 2.0 kg

• Onset of RSV associated-symptoms within 1 week of screening

• Confirmed* with RSV infection (by rapid antigen test or RT PCR)

• Hospitalized children fulfilling at least two of the following three RSV disease severity criteria:

  • Inadequate oral feeding
  • Inadequate oxygen saturation (peripheral capillary oxygen saturation [SpO2] <95% on room air or requiring oxygen supplementation to maintain SpO2 ≥95%)
  • Signs of respiratory distress (respiratory rate of ≥60 breaths per min for children aged up to 1 year, or ≥40 breaths per min for those older than 1 year, or accessory respiratory muscles use [subcostal, intercostal, or suprasternal retraction], or both)

Exclusion Criteria:

• Preterm infants (gestational age at birth less than 37 weeks) who are aged <56 days
• Being hospitalized for other clinically relevant concurrent conditions (except for risk factors for severe RSV, e.g., cardiac disease, pulmonary disease, genetic disease, and prematurity)
• Concurrent treatments with other agents with actual or possible direct antiviral activity against RSV <24 hours prior to study drug dosing (e.g. ribavirin)
• ALT or AST > 5 × ULN
• eGFR <30 mL/min/1.73m2 using the Schwartz formula if aged ≥1 year; or if aged <1 year based on a creatinine value cut off dependent on chronological age
• Any major congenital renal anomaly if <28 days
• Apgar score < 5 when last recorded if age <24 hours
• Known hypersensitivity to the study drug, the metabolites, or formulation excipient.
• On renal replacement therapies (e.g., intermittent hemodialysis, peritoneal dialysis, continuous renal replacement therapy)
• Any condition that, in the opinion of the site investigator, would make participation in the study unsafe for the child, or comprise the study objectives