A Two-Part Infant Study for Early Diagnosis of Respiratory Syncytial Virus (RSV) and Evaluation of JNJ-53718678 in RSV Acute Respiratory Tract Disease
Condition: Respiratory Syncytial Viruses
MeSH terms: Virus Diseases
Intervention: RSV Mobile Application; Placebo; JNJ-53718678 2.5 mg/kg; JNJ-53718678 3 mg/kg; JNJ-53718678 4.5 mg/kg
Intervention description: Participants will not receive any intervention in observational phase of this study. Participant's respiratory symptoms will be captured by RSV mobile application installed in participant's caregiver/parent mobile phone.; Participants in each Age Group (1,2,3) will receive matching placebo (volume placebo to match the calculated volume of the JNJ-53718678 dose) orally twice daily for 7 days.; JNJ-53718678 will be administered to Age Group 1 twice daily for 7 days.; JNJ-53718678 will be administered to Age Group 2 twice daily for 7 days.; JNJ-53718678 will be administered to Age Group 3 twice daily for 7 days.
Phase: Phase 2
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Enrollment: 22.0
Sex: All
Minimum age: 28 Days
Maximum age: 4 Months
Healthy volunteers: No

Summary:

      The purpose of this two-part designed study is to assess in the setting of a planned early
      interception of pediatric RSV disease, early viral and disease kinetics (observational stage)
      and the antiviral effects of an Respiratory Syncytial Virus (RSV) fusion inhibitor,
      JNJ-53718678 (interventional stage). In the observational stage the infant is closely
      monitored for early symptoms by the parent(s)/caregiver(s) and thus may be brought in for
      diagnosis earlier than in the typical setting.
    

Eligibility criteria:

        Inclusion Criteria:

        Part 1: Observational Stage

          -  The infant is less than or equal to (<=) 4 months of age at enrollment and
             asymptomatic for acute respiratory illness (ARI)-like symptoms requiring medical
             intervention at the time of consent to participate in the study

          -  At least 1 parent/caregiver must be able to use the respiratory syncytial virus (RSV)
             mobile application (App) at home via his/her own Android/iOS electronic device
             (compatible with RSV mobile App)

          -  The participant must have been assessed per local public health practice and
             considered not to have Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)
             infection

        Part 2: Interventional Stage

          -  The infant is 28 days and if prematurely born infant (that is [i.e.], less than [<] 37
             weeks and 0 days of gestation at birth) is at least 3 months postnatal age

          -  The participant has been diagnosed with RSV infection using a rapid molecular-based
             diagnostic assay

          -  The participant weighs more than 2.4 kilogram (kg)

          -  The participant has an acute respiratory illness as evaluated by the investigator

          -  Except for the RSV-related illness, the participant must be medically stable in case
             of allowed co-morbid conditions

          -  The participant must have been assessed per local public health practice and
             considered not to have SARS-CoV-2 infection during this respiratory infection

        Exclusion Criteria:

        Part 1: Observational Stage

          -  The participant has any physical abnormality which limits the ability to collect
             regular nasal specimens

          -  The participant is receiving chronic home oxygen therapy at enrollment (applicable to
             both parts)

        Part 2: Interventional Stage

          -  The participant is <3 months postnatal age at screening and was born prematurely
             (i.e., <37 weeks and 0 days of gestation) or if the participant weights <2.4 kg

          -  The participant has a QT interval with Fridericia's correction (QTcF) greater than (>)
             450 milliseconds per the machine read (mean of triplicate) parameter result confirmed
             by repeat triplicate Electrocardiogram (ECG) recording during screening

          -  The participant is considered by the investigator to be immunocompromised, whether due
             to underlying medical condition or medical therapy

          -  The participant has had any of: a) Confirmed SARS-CoV-2 infection (test positive)
             during the four weeks prior to randomization, or b) Close contact with a person with
             Coronavirus Disease 2019 (COVID-19) (test confirmed or suspected SARS-CoV-2 infection)
             within 14 days prior to randomization