Infant RSV Immunity Study

NCT07653347 | Recruiting

• 1 other identifier: F25-01060
• Study Type: observational
• Target: 300
• Locations: 1 country
• Sites: 1

Brief Summary

Respiratory Syncytial Virus (RSV) is a main global cause of respiratory illness and death in infants. Previous infant vaccine trials have failed to demonstrate protection. Moreover, RSV infection during early infancy, particularly in infants younger than 4 months of age, is associated with more severe disease, reduced immune protection, and an increased risk of developing childhood asthma. This study aim to investigate the immunological and long-term health effects of a first exposure to RSV early (\<4 months) versus late (\>6-9 months) in infancy.

Conditions

Respiratory Synctial Virus; Asthma Childhood

Keywords

cohort study; Immune response; infants; season of birth

Outcome Measures

Primary Outcomes (2)

• RSV antibody response

  i) RSV neutralization titers (expressed as dilution titer to prevent 95% neutralization in vitro; NT95) ii) RSV F-specific antibody-mediated complement activation iii) RSV F-specific antibody-mediated phagocytosis

  Post-respiratory season 2027 (May 2027)

• Asthma symptoms

  Children will be categorized as having low, moderate or high risk of asthma based on asthma-like symptoms defined using the Childhood Asthma Risk Tool (CHART)

  at age 3 years old

Secondary Outcomes (2)

• Medically attended RSV infections

  At 1 year and 3 years of age

• Wheezing

  During first RSV season (Sept to April), and each season, up to 3 years of age (for number of wheezing days during season).

Other Outcomes (1)

• Gut and upper airway microbiota

  0, 3, 6, 9 and 12 months

Study Arms (2)

Fall group/cohort

Infants exposed to RSV \<4 months of age (born September-November)

Spring group/cohort

Infants exposed to RSV \>6-9 months of age (born April-June)

Eligibility Criteria

• Age: Up to 6 Months
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17)
• Sampling Method: Non-Probability Sample

Study Population

Birthing parents who have a due date or delivery date in April, May or June 2026 (spring group/cohort) or September, October or November 2026 (fall group/cohort) with follow-up of the birthing parent and child during the 2026-2027, 2027-2028 and 2028-2029 RSV seasons. Children will be followed up to 3 years of age. The cohort will consist of 300 birthing parent-child pairs, with 150 in the spring cohort and 150 in the fall cohort. Birthing parents are recruited during antenatal care or shortly after delivery from the ultrasound clinic or delivery wards at BC Women's Hospital, patient lists from local maternity wards within the Vancouver Coastal Health Authority or advertisements at local prenatal care centres (obstetrician, physician and midwife clinics), community centres or on social media.

You may qualify if:

• Birthing parent/child pairs with a delivery date in April, May or June or September, October or November who delivered or are planning to deliver at BC Women's Hospital + Health Centre or a nearby, local hospital.

You may not qualify if:

• Severe pregnancy-related complications or chronic medical conditions in the children making them automatically eligible to receiving RSV immunoprophylaxis in British Columbia (e.g. infants born prematurely \< 35 weeks of gestation, or with chronic medical conditions).

Sponsors & Collaborators

• University of British Columbia: lead

Study Sites (1)

BC Women's Hospital and Health Centre

Vancouver, British Columbia, V6H 3N1, Canada

RECRUITING

Biospecimen

Retention: SAMPLES WITH DNA

Infant: * Cord blood/post-natal blood (\<1 month of age) * Dried blood spot at birth and pre-season (September) * Oral swabs (at 2 weeks of age + post-season) * Serial stool samples (2 weeks, 3, 6, 9 and 12 months of age) * Nasopharyngeal swabs (for resp virus testing + microbiome studies) at onset of seasonal acute RSV illnesses, with peripheral blood (2 weeks post-onset) Birthing parent: * Vaginal swab (\<2 weeks after birth) * Blood samples (antenatal, at delivery and at post-season visit).

Central Study Contacts

Pascal Lavoie, MDCM PhD FRCPC

CONTACT

604-875-2135; plavoie@bcchr.ca

Allison Watts, PhD

CONTACT

604-875-2000; awatts@bcchr.ca

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor and Neonatologist

Study Record Dates

• First Submitted: June 11, 2026
• First Posted: June 17, 2026
• Study Start: January 15, 2026
• Primary Completion (Estimated): June 1, 2027
• Study Completion (Estimated): December 1, 2029
• Last Updated: June 17, 2026

Record last verified: 2026-06

Locations

CA (1)