A Study of Rilematovir in Infants and Children and Subsequently in Neonates Hospitalized With Acute Respiratory Tract Infection Due to Respiratory Syncytial Virus (RSV)

Respiratory Tract Infections Clinical Trial

— DAISY  

Official title:

A Phase 3, Randomized, Double-blind, Placebo-controlled Study to Evaluate the Efficacy and Safety of Rilematovir in Infants and Children (≥28 Days to ≤5 Years of Age) and Subsequently in Neonates (<28 Days of Age), Hospitalized With Acute Respiratory Tract Infection Due to Respiratory Syncytial Virus (RSV)

Clinical Trial Details — Status: Terminated

Administrative data

• NCT number: NCT04583280
• Other study ID #: CR108899
• Secondary ID: 2020-002023-1153
• Status: Terminated
• Phase: Phase 3
• Start date: September 6, 2021
• Est. completion date: March 18, 2022

Study information

• Verified date: February 2024
• Source: Janssen Research & Development, LLC
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The purpose of the study is to evaluate the efficacy of rilematovir compared to placebo treatment with respect to the clinical outcome on the RSV Recovery Scale (RRS).

Description:

Respiratory syncytial virus (RSV), a negative-stranded ribonucleic acid (RNA) virus belonging to the Pneumoviridae family, is considered the most important cause of acute lower respiratory tract infection (LRTI) in infants and young children. In most patients, RSV results in upper respiratory tract infection (URTI) eliciting "common cold"-like symptoms, which might last up to 2 weeks, and are usually self-limiting. RSV-related LRTI is a major cause of hospital admissions and death in young children worldwide. Rilematovir is an investigational, small molecule, RSV fusion inhibitor. This study aims to evaluate the efficacy and safety of rilematovir in hospitalized infants and children (greater than or equal to [>=] 28 days to less than or equal to [<=] 5 years) and, subsequent to completion of the neonatal substudy, in hospitalized neonates (born at term, less than [<] 28 days of age) with RSV infection. The study will include a Screening Period, a Treatment Period, and a Follow-up Period. The total study duration for each participant will be approximately 36 days (Screening included). The efficacy assessments include evaluation under the RRS and the safety assessments include evaluations of physical examinations, vital signs, electrocardiograms, clinical laboratory tests, and adverse events.

Recruitment information / eligibility

• Status: Terminated
• Enrollment: 28
• Est. completion date: March 18, 2022
• Est. primary completion date: March 18, 2022
• Accepts healthy volunteers: No
• Gender: All
• Age group: 1 Day to 5 Years

Eligibility

Inclusion criteria:

• The participant weighs within greater than or equal to (>=) 2.4 kilograms (kg) and less than or equal to (<=) 24.6 kg

• Each participant's parent(s) (preferably both if available or as per local requirements) or their legally acceptable representative(s) has/have signed an informed consent form (ICF) indicating that (s)he understands the purpose of, and procedures required for, the study; is willing for their child to participate in the study; with regards to the concomitant medication, the lifestyle consideration and study procedures and assessments to be performed by the parent(s)/caregiver(s) as well as those by the investigator/study site personnel

• The participant has an acute respiratory illness with at least 1 of the signs/symptoms within 24 hours prior to start of screening and at screening, as evaluated by the investigator in Upper respiratory tract infection: nasal congestion or rhinorrhea; and Lower respiratory tract infection: increased respiratory effort (as evidenced by subcostal, intercostal or tracheosternal retractions, grunting, head bobbing, nasal flaring, or tachypnea), wheezing, cough, cyanosis, or apnea; and systemic/general: feeding difficulties (defined as <75 percent [%] intake of normal food amounts); dehydration; fever; disturbed sleep, or disturbed activity level (irritable/restless/agitated/less responsive). Cough or wheezing cannot be the only LRTI sign/symptom present, that is, at least one other LRTI sign/symptom needs to be present for eligibility

• The time of onset of RSV signs/symptoms to the anticipated time of randomization must be less than or equal to (<=) 3 days. Onset of signs/symptoms is defined as the time of the day (or part of the day if time of the day cannot be specified) the parent(s)/caregiver(s) became aware of the first sign and/or symptom consistent with respiratory or systemic/general manifestation of signs/symptoms of RSV infection. The time of sign/symptom onset has to be assessed as accurately as possible

• Participants are otherwise healthy or have (a) risk factor(s) for severe RSV disease

Exclusion criteria:

• The participant has had either confirmed severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection (test positive) during the four weeks prior to randomization, or close contact with a person with COVID-19 (test confirmed or suspected SARS CoV-2 infection) within 14 days prior to randomization

• Confirmed QT interval corrected for heart rate according to Fridericia's formula (QTcF) interval greater than (>) 450 milliseconds (msec) per the machine read parameter result at screening. Presence of an abnormal QTcF interval should be confirmed by repeat electrocardiogram (ECG) recording during screening

• Known personal or family history of Long QT Syndrome or sudden cardiac death

• Presence of repetitive ventricular premature contractions (>10/minutes [min]), second- or third-degree heart block, or complete or incomplete left bundle branch block, or complete right bundle branch block per the machine read ECG result at screening. Presence of any of the above abnormalities should be confirmed by repeat ECG recording during screening

Related Conditions & MeSH terms

• Communicable Diseases
• Infections
• Respiratory Tract Infections

Intervention

Drug:
• Rilematovir
Participants of age group greater than or equal to (>=) 28 days to less than (<) 3 months (age group 1) or >= 3 months to < 6 months (age group 2) or >= 6 months to less than or equal to (<=) 5 years (age group 3) will receive rilematovir orally twice a day (BID) from Days 1 to Day 7 or Day 8.
• Rilematovir X mg/kg
Participants of age group birth at term (after at least 37 weeks of gestation) to < 28 days (age group 4) will receive rilematovir orally BID from Days 1 to Day 7 or Day 8. The dose is dependent on outcome of the substudy in neonates and following independent data monitoring (IDMC) review and recommendation.
• Placebo
Participant of age group 1, 2, 3 and 4 will receive matching placebo of rilematovir BID from Days 1 to Day 7 or Day 8 as per assigned age group.

Locations

Country	Name	City	State
Argentina	Hospital Interzonal General de Agudos Dr. Jose Penna	Bahia Blanca
Argentina	Hospital Italiano Regional Del Sur	Bahía Blanca
Argentina	Hospital General de Niños Pedro de Elizalde	Buenos Aires
Argentina	Hospital Universitario Austral	Pilar
Argentina	Instituto Medico Rio Cuarto	Rio Cuarto
Argentina	Clinica Mayo de UMCB	San Miguel de Tucuman
Argentina	Hospital del Niño Jesús	San Miguel de Tucumán
Belgium	ULB Hôpital Erasme	Anderlecht
Belgium	AZ Sint-Jan Brugge-Oostende AV	Brugge
Belgium	UZ Brussel	Brussel
Belgium	Cliniques Universitaires Saint Luc	Bruxelles
Belgium	UZ Leuven	Leuven
Brazil	Santa Casa de Misericordia de Belo Horizonte	Belo Horizonte
Brazil	Fundacao para o Desenvolvimento Medico Hospitalar (UNESP Botucatu)	Botucatu
Brazil	Sociedade Campineira de Educacao e Instrucao - Hospital e Maternidade Celso Pierro	Campinas
Brazil	Nucleo de Pesquisa do Hospital Pequeno Princípe	Curitiba
Brazil	Secretaria da Saude do Estado do Ceara - Hospital Doutor Carlos Alberto Studart Gomes	Fortaleza
Brazil	Associacao Hospitalar Moinhos de Vento	Porto Alegre
Brazil	Hospital das Clínicas da Faculdade de Medicina de RPUSP - HCRP	Ribeirão Preto
Brazil	Fundacao Jose Luiz Egydio Setubal	Sao Paulo
Brazil	Santa Casa de Misericórdia de Votuporanga	Votuporanga
Bulgaria	UMHAT 'Sveti Georgi'-Plovdiv	Plovdiv
Bulgaria	UMHAT 'Kanev' EAD	Ruse
Bulgaria	Acibadem City Clinic Tokuda Hospital	Sofia
Bulgaria	SHATCD 'Prof. Ivan Mitev' EAD	Sofia
Bulgaria	UMHAT 'Aleksandrovska' EAD	Sofia
China	Beijing Children's Hospital, Capital Medical University	Beijing
China	Capital Institute of Pediatrics	Beijing
China	Peking University Third Hospital	Beijing
China	West China Second University Hospital, Sichuan University	Chengdu
China	Guangzhou Women And Children's Medical Center	Guangzhou
Czechia	Fakultni nemocnice Brno	Brno
Czechia	Fakultni nemocnice Kralovske Vinohrady	Praha 10
Czechia	Thomayerova nemocnice	Praha 4
Estonia	Tallinn Children's Hospital	Tallinn
Estonia	Tartu University Hospital	Tartu
Germany	Universitätsklinik Freiburg	Freiburg
Germany	HELIOS Klinikum Wuppertal GmbH	Wuppertal
Germany	Universitatsklinikum Wurzburg	Würzburg
Hungary	Bethesda Gyermekkórház	Budapest
Hungary	Semmelweis Egyetem, II. sz. Gyermekgyógyászati Klinika	Budapest
Hungary	Debreceni Egyetem Klinikai Kozpont	Debrecen
Hungary	Petz Aladar Megyei Oktato Korhaz	Gyor
Hungary	Bacs-kiskun Megyei Korhaz	Kecskemet
Hungary	Borsod-Abauj-Zemplen Megyei Korhaz es Egyetemi Oktato Korhaz	Miskolc
Hungary	Szegedi Tudomanyegyetem	Szeged
Hungary	Csolnoky Ferenc Korhaz	Veszprém
Israel	Soroka University Medical Center	Beer-Sheba
Israel	Ruth Rappaport Children's Hospital, Rambam Health Care Campus	Haifa
Israel	Schneider Children's Medical Center	Petah Tikva
Israel	Pediatrics B, Safra Children's Hospital, Tel Hashomer	Ramat Gan
Israel	Sourasky MC	Tel-Aviv
Italy	A.O.U Sant'Orsola-Malpighi	Bologna
Italy	Università degli Studi di Milano, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico	Milan
Italy	Department of Pediatrics University of Pavia, Policlinico San Matteo	Pavia
Italy	Ospedale degli Infermi	Ponderano
Japan	Fukui Prefectural Hospital	Fukui-shi
Japan	Fukuyama City Hospital	Fukuyama
Japan	Kagoshima Children's Hospital	Hioki
Japan	Teine Keijinkai Hospital	Hokkaido
Japan	National Hospital Organization Kanazawa Medical Center	Ishikawa
Japan	Japan Community Health care Organization Kyushu Hospital	Kitakyushu-shi,
Japan	Kobe City Medical Center General Hospital	Kobe
Japan	Kochi Health Sciences Center	Kochi
Japan	Maebashi Red Cross Hospital	Maebashi
Japan	Daido Hospital	Nagoya
Japan	National Hospital Organization Niigata National Hospital	Niigata
Japan	National Hospital Organization Beppu Medical Center	Oita
Japan	National Hospital Organization Saitama National Hospital	Saitama
Japan	National Hospital Organization Ureshino Medical Center	Ureshino-shi
Japan	Yamanashi Prefectural Central Hospital	Yamanashi
Korea, Republic of	Kyungpook National University Hospital	Daegu
Korea, Republic of	CHA Bundang Medical Center, CHA University	Gyeonggi-do
Korea, Republic of	Inje University Sanggye Paik Hospital	Seoul
Korea, Republic of	Kangbuk Samsung Hospital	Seoul
Korea, Republic of	Korea Institute of Radiological and Medical Sciences	Seoul
Korea, Republic of	Nowon Eulji Medical Center, Eulji University	Seoul
Korea, Republic of	Samsung Medical Center	Seoul
Latvia	Children's Clinical University Hospital	Riga
Malaysia	Hospital Selayang	Batu Caves
Malaysia	Hospital Bintulu	Bintulu
Malaysia	Hospital Miri	Miri
Malaysia	Hospital Sibu	Sibu
Malaysia	Hospital Taiping	Taiping
Mexico	Hospital Infantil de Mexico Federico Gomez	Ciudad De Mexico
Mexico	Instituto Nacional de Pediatría	Ciudad de Mexico
Mexico	Centro Medico Zambrano Hellion	Monterrey
Mexico	Hospital Universitario 'Dr. Jose Eleuterio Gonzalez'	Monterrey
Panama	Cevaxin Avenida Mexico	Panama
Poland	Krakowski Szpital Specjalistyczny im Jana Pawla II	Krakow
Poland	Wojewodzkie Wielospecjalistyczne Centrum Onkologii i Traumatologii im. M. Kopernika w Lodzi	Lodz
Poland	Uniwersytecki Szpital Dzieciecy w Lublinie	Lublin
Poland	Dzieciecy Szpital Kliniczny im. Jozefa Polikarpa Brudzinskiego	Warszawa
Slovakia	DFNsP Banska Bystrica	Banska Bystrica
Slovakia	Pediatric Pulmonology Clinic, University Hospital Bratislava	Bratislava
Spain	Hosp. Univ. Germans Trias I Pujol	Badalona
Spain	Hosp. Univ. de Cruces	Barakaldo
Spain	Hosp. Reina Sofia	Córdoba
Spain	Hosp. Univ. de Getafe	Getafe
Spain	Hosp. Univ. 12 de Octubre	Madrid
Spain	Hosp. Univ. Fund. Jimenez Diaz	Madrid
Spain	Hosp. Univ. Hm Monteprincipe	Madrid
Spain	Hosp. Univ. La Paz	Madrid
Spain	Hosp. Univ. Severo Ochoa	Madrid
Spain	Hosp. Univ. Pta. de Hierro Majadahonda	Majadahonda
Spain	Hosp. Puerta Del Sur	Mostoles
Spain	Complejo Hosp. de Navarra	Pamplona
Spain	Hosp. Quiron Madrid Pozuelo	Pozuelo de Alarcón
Spain	Hosp. Clinico Univ. de Santiago	Santiago de Compostela
Sweden	Astrid Lindgrens barnsjukhus Solna	Stockholm
Taiwan	Hsinchu MacKay Memorial Hospital	Hsinchu
Taiwan	Taipei Medical University Shuang Ho Hospital	New Taipei City
Taiwan	Mackay Memorial Hospital	Taipei
Taiwan	National Taiwan University Hospital	Taipei
Taiwan	Chang Gung Medical Foundation	Taoyuan City
Thailand	Siriraj Hospital Mahidol University	Bangkok
Thailand	Tropical Medicine Hospital, Mahidol University	Bangkok
Thailand	Maharaj Nakorn Chiangmai Hospital	Chiang Mai
Thailand	Srinagarind Hospital	Khon Kaen
Thailand	Bamrasnaradura Infectious Disease Institute	Nonthaburi
Thailand	Faculty of Medicine Chulalongkorn University	Pathumwan
Turkey	Cukurova University Medical Faculty Balcali Hospital	Adana
Turkey	Gazi University Medical Faculty	Ankara
Turkey	Hacettepe University Medical Faculty	Ankara
Turkey	Istanbul University Istanbul Medical Faculty	Istanbul
Turkey	Ege University Medical Faculty	Izmir
Turkey	Saglik Bilimleri University Sariyer Hamidiye Etfal Training and Research Hospital	Sariyer
Turkey	Karadeniz Teknik University Medical Faculty	Trabzon
Ukraine	ME 'Dnipropetrovsk Regional Children's Clinical Hospital of Dnipropetrovsk Regional Council'	Dnipro
Ukraine	MNPE City Children's Clinical Hospital ? 6 of Dnipro City Council	Dnipro
Ukraine	Kharkiv National Medical University on based CHPI Kharkiv Municipal Clinical Children's Hospital 16	Kharkiv
Ukraine	MUNICIPAL NON-PROFIT ENTERPRISE 'Kryvyi Rih CITY HOSPITAL ?16' Kryvyi Rih CITY COUNCIL	Kryvyi Rih
Ukraine	Odessa Regional Child Hospital	Odessa
Ukraine	SSU Division MU Ch of pediatrics of PGE with propedeutic pediatrics and children infections course	Sumy
Ukraine	Sumy Regional Childrens Clinical Hospital	Sumy
Ukraine	Municipal institution 'Vinnytsia Regional Clinical Children's Infectious Diseases Hospital'	Vinnytsia
Ukraine	MNPE Zaporizhzhya Regional Clinical Children's Hospital of Zaporizhzhya Regional Council	Zaporizhzhia
United States	Jacobi Medical Center	Bronx	New York
United States	University of Mississippi Medical Center	Jackson	Mississippi
United States	Le Bonheur Children's Hospital	Memphis	Tennessee
United States	Arnold Palmer Hospital For Children	Orlando	Florida
United States	MultiCare Health Systems for Research and Innovation	Tacoma	Washington

Sponsors (1)

Lead Sponsor	Collaborator
Janssen Research & Development, LLC

Countries where clinical trial is conducted

United States,  Argentina,  Belgium,  Brazil,  Bulgaria,  China,  Czechia,  Estonia,  Germany,  Hungary,  Israel,  Italy,  Japan,  Korea, Republic of,  Latvia,  Malaysia,  Mexico,  Panama,  Poland,  Slovakia,  Spain,  Sweden,  Taiwan,  Thailand,  Turkey,  Ukraine, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Percentage of Participants by Respiratory Syncytial Virus (RSV) Recovery Scale (RRS) Category	RRS was an ordinal scale to assess a participant's clinical status. The RRS provided 7 mutually exclusive categories ordered from best (1) to worst (7) where 1 =home without signs/symptoms, 2 =home with sign/symptoms, 3 =ward without supplemental oxygen (O2) or feeding/hydration, 4 =ward with supplemental or feeding/hydration, 5 =intensive care unit (ICU) without mechanical ventilation (included both invasive and non-invasive mechanical ventilation), 6 =required mechanical ventilation and 7=worst (death). Higher category indicates worse condition. With or without signs/symptoms was defined as the key RSV signs/symptoms (breathing problems, retractions, tachypnea, cough, wheezing/breathing sounds, and tachycardia) resolved (absent or mild) or not resolved assessed by parent/caregiver.	Baseline to Day 8
Secondary	Percentage of Participants Clinically Resolved From RSV Disease Based on the Clinician Reported Outcome (ClinRO) Sign/Symptoms at Day 8	Clinically resolved was defined as participant required no oxygen supplementation, no supplemental feeding/hydration, no need for ICU and had Key RSV signs/symptoms resolved to absent or mild as per ClinRO signs/symptoms. Clinically resolved Key RSV signs/symptoms were assessed based on clinician's observations as resolved if participant had no retractions, tachypnea, tachycardia, breathing problems (nasal flaring, head bobbing, grunting); cough (resolved if little or no coughing or occasional strong cough or sometimes productive) and wheezing (resolved if no wheezing or terminal expiratory wheezing or only with stethoscope).	Day 8
Secondary	Time From First Study Dose to Resolution of Key RSV Signs/Symptoms Based on Observer Reported Outcome (ObsRO) After Free of Supplementation (Oxygen/Feeding/Hydration) for at Least 24 Hours	Time (in hours) from first dose of study intervention to first resolution of key RSV signs/symptoms was evaluated based on ObsRO assessment after free of supplementation (O2/feeding/hydration) for at least 24 hours. Clinically resolved was defined as participant required no oxygen supplementation, no supplemental feeding/hydration, no need for ICU and had key RSV signs/symptoms resolved to absent or mild as per ObsRO signs/symptoms. Resolution of key signs/symptoms assessment was based on observations of child's parent/caregiver as resolved if no retractions, tachypnea, tachycardia, breathing problems (gasping for air nostrils, flaring when breathing, head bobbed back and forth when breathing), no breathing sound; cough (no coughing, little coughing without problems). Kaplan-Meier method was used for estimation.	Up to Day 21
Secondary	Number of Participants With Post-baseline RSV-related Complications	RSV related complications included respiratory complications (respiratory failure, apnoeic attacks, bronchiolitis, bronchial obstruction, pneumonia and asthmatic crisis), infectious complications (otitis media, bacterial respiratory tract infections and sepsis), cardiovascular complications (arrhythmia, cardiogenic shock, hemodynamic instability, congestive cardiac failure), acid-base or electrolyte complications (metabolic acidosis, metabolic alkalosis, hyponatremia, hypokalemia, hyperkalemia, hypocalcemia, hypercalcemia, hypoglycemia and hyperglycemia). Participants were counted only once, regardless of the number of complications they actually experienced.	Up to Day 35
Secondary	Number of Participants With Treatment-emergent Adverse Events (TEAEs)	An adverse event (AE) is any untoward medical occurrence in a clinical study participant administered a medicinal (investigational or non-investigational) product and did not necessarily have a causal relationship with the treatment. A TEAE was defined as an AE with an onset after the initiation study drug (Day 1) up to end of study (Day 35). AEs included both serious and non-serious AEs.	Day 1 up to Day 35
Secondary	Number of Participants With Abnormalities in Clinical Laboratory Values	Number of participants with abnormally low (AL) and abnormally high (AH) values of bicarbonate, direct bilirubin, urea nitrogen, basophils, eosinophils, erythrocyte (Ery). mean corpuscular hemoglobin (HGB) concentration (conc), Ery. mean corpuscular hemoglobin, erythrocytes, leukocytes, lymphocytes, monocytes, neutrophils and reticulocytes were reported based on the investigator's discretion.	Up to Day 35
Secondary	Number of Participants With Abnormalities in Electrocardiograms (ECGs)	Number of participants with abnormally low and abnormally high values of ECG parameters (PR interval and RR interval) as assessed based on the investigator's discretion were reported.	Up to Day 35
Secondary	Number of Participants With Abnormalities in Vital Signs	Number of participants with abnormally low and abnormally high values of vital signs from baseline were assessed based on investigator's discretion. Vital signs included systolic blood pressure (SBP) (millimeter of mercury [mmHg]), diastolic blood pressure (DBP) (mmHg), pulse rate (beats per minute), respiratory rate (breaths per minute), temperature (degree Celsius) and oxygen saturation (in percentage).	Up to Day 35
Secondary	Percentage of Participants Requiring Intensive Care Unit (ICU) Stay After First Dose of Rilematovir	Percentage of participants requiring ICU stay was analyzed and reported.	Up to Day 35
Secondary	Duration of ICU Stay	Duration (in hours) of ICU stay was defined as total number of hours a participant experienced an ICU stay from first dose of rilematovir until study termination, calculated as the sum of all separate records of ICU stay.	Up to Day 35
Secondary	Percentage of Participants Requiring Re-hospitalization for Respiratory/Other Reasons	Percentage of participants requiring re-hospitalization (participants re-hospitalized [ward or ICU] after been discharged from hospital) for respiratory/other reasons were reported.	Up to Day 35
Secondary	Percentage of Participants Requiring Oxygen Supplementation After First Dose of Rilematovir	Percentage of participants requiring any type of oxygen supplementation (invasive mechanical ventilation, non-invasive mechanical ventilation and non-invasive non-mechanical ventilation) were reported.	Up to Day 35
Secondary	Duration of Oxygen Supplementation	Duration (in hours) of oxygen supplementation was defined as total number of hours a participant used supplemental oxygen from either prior to first dose and/or after first dose of drug until study termination, calculated as the sum of all separate records of supplementation.	Up to Day 35
Secondary	Percentage of Participants Requiring Hydration and/or Feeding by Intravenous (IV) Administration or Nasogastric Tube After First Dose of Rilematovir	Percentage of participants requiring any type of hydration and/or feeding by intravenous (IV) administration or nasogastric tube or percutaneous endoscopic gastrostomy was reported.	Up to Day 35
Secondary	Duration of Supplemental Feeding/Hydration	Duration (in hours) of supplemental feeding/hydration was defined as total number of hours a participant was administered feeding/hydration supplementation from either prior to first dose and/or after first dose of drug until study termination, calculated as the sum all separate records of supplementation use per participant.	Up to Day 35
Secondary	Number of Participants With Medical Encounters and Treatments	Medical resource utilization was assessed by medical care encounters and treatments. Medical encounters and treatments included physician or emergency room visits, tests and procedures, and medications, surgeries and other selected procedures, inpatient and outpatient.	Up to Day 35
Secondary	RSV Viral Load at Baseline, Days 2, 3, 5, 8, 14 and 21	Antiviral activity was determined based on measurements of RSV viral load which was measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR) in the mid-turbinate (MT) nasal swab specimens.	Baseline, Days 2, 3, 5, 8, 14 and 21
Secondary	Change From Baseline in RSV Viral Load at Days 2, 3, 5, 8, 14 and 21	Antiviral activity was determined based on measurements of RSV viral load which was measured by qRT-PCR in the MT nasal swab specimens.	Baseline, Days 2, 3, 5, 8, 14 and 21
Secondary	Percentage of Participants With Undetectable RSV Viral Load	Percentage of participants with undetectable RSV viral load was analyzed.	Baseline, Days 2, 3, 5, 8, 14 and 21
Secondary	Plasma Concentrations of Rilematovir	Plasma concentrations of rilematovir were assessed. Participant wise data were reported for this outcome measure.	1 hour Post-dose (Day 1) and pre-dose (Day 2)
Secondary	Percentage of Participants With Acceptability and Palatability of the Rilematovir Formulation as Assessed by Parent(s)/Caregiver(s)	Acceptability and palatability were assessed by clinician electronic clinical outcome assessment (eCOA) questionnaire which consisted of 7 questions, 1- child took medicine easily, 2- disgusted expressions after tasting medicine, 3- cried after tasting medicine, 4- would not open mouth or turned head away to avoid medicine, 5- spit out or coughed out medicine, 6- gagged, 7- vomited (within 2 minutes of swallowing medicine).	Day 8