Study to Assess the Safety, Pharmacokinetics, and Efficacy of Baloxavir Marboxil in Healthy Pediatric Participants With Influenza-Like Symptoms
Condition: Influenza
MeSH terms: Influenza, Human
Intervention: Baloxavir Marboxil; Oseltamivir
Intervention description: Baloxavir marboxil will be administered as oral suspension in a single dose on Day 1.
Oseltamivir matching placebo will also be administered as oral suspension twice daily (BID) for 5 days.; Oseltamivir will be administered as oral suspension BID for 5 days. Participants receiving oseltamivir will also receive baloxavir marboxil matching placebo as oral suspension, single dose on Day 1.
Intervention MeSH terms: Oseltamivir; Baloxavir
Phase: Phase 3
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Enrollment: 173.0
Sex: All
Minimum age: 1 Year
Maximum age: 11 Years
Healthy volunteers: No

Summary:

      This study will evaluate the safety, pharmacokinetics, and efficacy of baloxavir marboxil
      compared with oseltamivir in a single influenza episode in otherwise healthy pediatric
      participants (i.e., 1 to <12 years of age) with influenza-like symptoms.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Aged 1 to < 12 years at randomization (Day 1).

          -  Written informed consent/assent for study participation obtained from participant's
             parents or legal guardian, with assent as appropriate by the participant, depending on
             the patient's level of understanding

          -  Participant able to comply with study requirements, depending on the patient's level
             of understanding

          -  Participant with a diagnosis of influenza virus infection confirmed by the presence of
             all of the following:

          -  Fever ≥ 38 degree celsius (tympanic temperature) at screening

          -  At least one respiratory symptom (either cough or nasal congestion)

          -  The time interval between the onset of symptoms and screening is ≤ 48 hours

        Exclusion Criteria:

          -  Severe symptoms of influenza virus infection requiring inpatient treatment

          -  Concurrent infections requiring systemic antiviral therapy at screening

          -  Require, in the opinion of the investigator, any of the prohibited medication during
             the study

          -  Previous treatment with peramivir, laninamivir, oseltamivir, zanamivir, or amantadine
             within 2 weeks prior to screening

          -  Immunization with a live/attenuated influenza vaccine in the 2 weeks prior to
             randomization

          -  Concomitant treatment with steroids or other immuno-suppressant therapy

          -  Known HIV infection or other immunosuppressive disorder

          -  Uncontrolled renal, vascular, neurologic, or metabolic disease (e.g., diabetes,
             thyroid disorders, adrenal disease), hepatitis, cirrhosis, or pulmonary disease or
             participants with known chronic renal failure.

          -  Active cancer at any site

          -  History of organ transplantation

          -  Known allergy to either study drug (i.e., baloxavir marboxil and oseltamivir) or to
             acetaminophen

          -  Females with child-bearing potential

          -  Participation in a clinical trial within 4 weeks or five half-lives of exposure to an
             investigational drug prior to screening, whichever is longer