Prospective Surveillance of Respiratory Syncytial Virus Disease in Infants and Toddlers

Study Overview
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Brief Summary
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The study is a multi-center, multi-national, prospective surveillance study in which the study participants will not receive a study vaccine but will provide a baseline blood sample and be followed for acute respiratory disease during 6 months. The 6-month follow-up will occur for the most part during the Respiratory Syncytial Virus(RSV) season (based on enrollment timing and as per feasibility). A maximum of 1000 children from 6 to < 22 months of age are planned to be enrolled in 5 to 10 countries, 1 to 2 sites per country, targeting approximately 100 participants per country. The purpose of the study is to assess the seroprevalence and incidence of RSV disease during the study period in the targeted countries and sites for a Phase III vaccine study.

Detailed Description
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The duration of the study will be 6 months for each participant.

Official Title
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A Multi-center, Multi-national, Prospective Surveillance Study of Respiratory Syncytial Virus Disease in Infants and Toddlers 6 to < 22 Months of Age

Conditions
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Respiratory Syncytial Virus Infections

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged 6 months to < 22 months on the day of inclusion (means the day of the 6-month birthday to the day before the 22-month birthday) Participants who are healthy as determined by medical evaluation including medical history Born at full term of pregnancy (≥ 37 weeks) or born after a gestation period of 27 through 36 weeks and medically stable as assessed by the investigator, based on the following definition: Medically stable refers to the condition of premature infants who do not require significant medical support or ongoing management for debilitating disease and who have demonstrated a clinical course of sustained recovery by the time they are enrolled in the study Exclusion Criteria: Known or suspected congenital or acquired immunodeficiency; or receipt of immunosuppressive therapy, such as anti-cancer chemotherapy or radiation therapy, within the preceding 6 months; or long-term systemic corticosteroid therapy (prednisone or equivalent for more than 2 consecutive weeks within the past 3 months) Chronic illness that, in the opinion of the investigator, is at a stage where it might interfere with study conduct or completion Probable or confirmed ongoing case of viral respiratory infection (including COVID-19, influenza, rhinovirus, etc.) at the time of enrollment. A prospective participant should not be included in the study until the respiratory infection has resolved Member of a household that contains an immunocompromised individual, including, but not limited to: a person who is human immunodeficiency virus (HIV) infected a person who has received chemotherapy within the 12 months prior to study enrollment a person who has received (within the past 6 months) or is receiving (at the time of enrollment) immunosuppressant agents a person living with a solid organ or bone marrow transplant Participant's mother previous receipt or planned administration of an investigational RSV vaccine during pregnancy and/or breastfeeding Receipt or planned receipt of any of the following vaccines: Any intranasal live attenuated vaccine within the 28 days prior to enrollment Any injectable live attenuated vaccine within the 28 days prior to and after enrollment Previous receipt of an investigational RSV vaccine or receiving any anti-RSV product (such as ribavirin or RSV immune globulin or RSV monoclonal antibody) less than 6 months before enrollment Receipt of immune globulins, blood or blood-derived products in the past 3 months Participation at the time of study enrollment or planned participation during the present study period in another clinical study investigating a vaccine, drug, medical device, or medical procedure The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial

Ages Eligible for Study
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Minimum Age: 6 Months
Maximum Age: 21 Months

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Healthy children aged 6 months to < 22 months<br>No vaccine will be administered. All enrolled participants will have a blood sample collected at enrollment (visit 01) and a nasal swab collected each time they have an RSV-like illness visit | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| RSV A serum neutralizing antibody (Nab) titers | To assess RSV A serum Nab titers overall | At Day 1 | 
| RSV A serum neutralizing antibody (Nab) titers | To assess RSV A serum Nab titers by country | At Day 1 | 
| RSV B serum Nab titers | To assess RSV B serum Nab titers overall | At Day 1 | 
| RSV B serum Nab titers | To assess RSV B serum Nab titers overall by country | At Day 1 | 
| Anti-F immunoglobulin A (IgA) and G (IgG) enzyme linked immunosorbant assay (ELISA) titers | To assess Anti-F IgA and IgG ELISA titers overall | At Day 1 | 
| Anti-F immunoglobulin A (IgA) and G (IgG) enzyme linked immunosorbant assay (ELISA) titers | To assess Anti-F IgA and IgG ELISA titers by country | At Day 1 | 
| Baseline serostatus | To assess baseline serostatus overall | At Day 1 | 
| Baseline serostatus | To assess baseline serostatus by country | At Day 1 | 
| Occurrence of ARD associated with any RT PCR confirmed RSV strain during the study | To assess to incidence of ARD confirmed by RT PCR overall | Throughout study, approximately 6 months | 
| Occurrence of ARD associated with any RT PCR confirmed RSV strain during the study | To assess to incidence of ARD confirmed by RT PCR by country | Throughout study, approximately 6 months | 
| Occurrence of LRTD associated with any RT PCR confirmed RSV strain during the study | To assess to incidence of LRTD confirmed by RT PCR overall | Throughout study, approximately 6 months | 
| Occurrence of LRTD associated with any RT PCR confirmed RSV strain during the study | To assess to incidence of LRTD confirmed by RT PCR by country | Throughout study, approximately 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| RSV A serum Nab titers | To assess RSV A serum Nab titers for each age group overall | At Day 1 | 
| RSV A serum Nab titers | To assess RSV A serum Nab titers for each age group by country | At Day 1 | 
| RSV B serum Nab antibody titers | To assess RSV B serum Nab titers for each age group overall | At Day 1 | 
| RSV B serum Nab antibody titers | To assess RSV B serum Nab titers for each age group by country | At Day 1 | 
| Anti-F IgA and IgG ELISA titers | To assess Anti-F IgA and IgG ELISA titers for each age group overall | At Day 1 | 
| Anti-F IgA and IgG ELISA titers | To assess Anti-F IgA and IgG ELISA titers for each age group by country | At Day 1 | 
| Baseline serostatus by age group | To assess baseline serostatus for each age group overall | At Day 1 | 
| Baseline serostatus by age group | To assess baseline serostatus for each age group by country | At Day 1 | 
| Occurrence of ARD associated with any RT PCR confirmed RSV strain during the study | To assess to incidence of ARD confirmed by RT PCR for each age group overall | Throughout study, approximately 6 months | 
| Occurrence of ARD associated with any RT PCR confirmed RSV strain during the study | To assess to incidence of ARD confirmed by RT PCR for each age group by country | Throughout study, approximately 6 months | 
| Occurrence of LRTD associated with any RT PCR confirmed RSV strain during the study | To assess to incidence of LRTD confirmed by RT PCR for each age group overall | Throughout study, approximately 6 months | 
| Occurrence of LRTD associated with any RT PCR confirmed RSV strain during the study | To assess to incidence of LRTD confirmed by RT PCR for each age group by country | Throughout study, approximately 6 months | 
| Occurrence of ARD associated with each RT-PCR confirmed RSV strain (A/B) during the study | To assess to incidence of ARD confirmed by RT PCR for each strain overall | Throughout study, approximately 6 months | 
| Occurrence of ARD associated with each RT-PCR confirmed RSV strain (A/B) during the study | To assess to incidence of ARD confirmed by RT PCR for each strain by country | Throughout study, approximately 6 months | 
| Occurrence of severe LRTD associated with any RT PCR confirmed RSV strain during the study | To assess the severity of LRTD confirmed by any RT PCR for each strain | Throughout study, approximately 6 months | 
| Occurrence of LRTD associated with each RT-PCR confirmed RSV strain (A/B) during the study | To assess to incidence of LRTD confirmed by RT PCR for each strain overall | Throughout study, approximately 6 months | 
| Occurrence of LRTD associated with each RT-PCR confirmed RSV strain (A/B) during the study | To assess to incidence of LRTD confirmed by RT PCR for each strain by country | Throughout study, approximately 6 months | 
| Occurrence of clinically diagnosed RSV ARD according to routine practice (with or without RT-PCR RSV confirmation) during the study |  | Throughout study, approximately 6 months | 
| Occurrence of clinically diagnosed RSV LRTD according to routine practice (with or without RT-PCR RSV confirmation) during the study |  | Throughout study, approximately 6 months | 
| Occurrence of AOM episodes during the study |  | Throughout study, approximately 6 months | 
| Occurrence of ARD and LRTD associated with any RT PCR confirmed RSV strain during the study, RSV A and RSV B serum neutralizing antibody titers, anti-F IgA and IgG ELISA antibody titers | To assess the association between RT-PCR confirmed RSV ARD and LRTD and RSV A, B, anti-G IgA an IgG ELISA antibodies at baseline | At Day 1 |