Respiratory Synctial VirusIRISNCT07653347
Infant RSV Immunity Study
An observational study of Respiratory Synctial Virus and Asthma Childhood, run by University of British Columbia at 1 site in Canada.
Trial 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… Read more about this study
- Who is it for?
- Ages Up to 6 monthsHealthy volunteers can take part
- Conditions the study is for
- Respiratory Synctial Virus, Asthma Childhood
- How many people
- 300 participants
- Where
- 1 siteCanada
- Study dates
- 15 Jan 2026to 1 Dec 2029
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages Up to 6 months
- All sexes
- Healthy volunteers accepted
- Child
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.
Who may be able to join
- 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.
Who cannot join
- 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).
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Canada1 site, 1 recruiting
- Recruiting
BC Women's Hospital and Health Centre
Vancouver, British Columbia, V6H 3N1
Pascal Lavoie, MD PhD, (604) 875-2000 ext. 7318, plavoie@bcchr.ca
Allison Watts, PhD, 604-875-2135, awatts@bcchr.ca
About this study
Official title: Understanding the Impact of Early-life RSV Infections on Infant Immunity and Long-term Health
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.
Read the detailed description
In British Columbia (Canada), RSV cases rise each year after mid-October, until April, peaking in December. This study compares outcomes between infants born in April to June, who will be naturally exposed to RSV >6-9 months of age versus infants born in September to November, who will be naturally exposed to RSV <4 months of age. Most infants become infected during their first RSV year.
Primary Objectives:
- Compare post-season RSV immune responses between the spring cohort of infants born in April to June versus the fall cohort of infants born in September to November.
- Compare respiratory outcomes at 3 years of age between the spring cohort of infants born in April to June versus the fall cohort of infants born in September to November.
Secondary Objectives:
- Identify immune maturation events linked to stronger post-season RSV antibody responses.
- Determine how the gut and upper airway microbiota co-evolve in infants over the first year of life, and how these dynamics shape RSV risk, and are shaped by host-related, and specifically seasonal factors (i.e. Apr-Jun versus Sept-Nov).
- Compare immune responses during acute RSV infections between the spring cohort of infants born in April to June versus the fall cohort of infants born in September to November.
Design:
Prospective, observational cohort study of 300 parent-infant pairs born in the spring (April-June) or fall (Sept-Nov), with follow-up at 3 years of age.
Recruitment and Informed Consent Procedure:
Birthing parents planning to give birth at the BC Women's Hospital or live locally in greater Vancouver are identified through the BC Women's Hospital prenatal ultrasound clinic or social media and contacted by the study coordinator in person, by telephone or by text message. Interested participants complete an online eligibility questionnaire and, if eligible, the online consent form. Study advertisements posted in the hospital, local clinics, local community centers and on social media direct interested parents to the study website, online eligibility questionnaire and the study coordinators contact information.
Patients who delivered an infant during the study eligibility period in the Vancouver Coastal Health region are also invited by mail and enrolled prior to the start of the respiratory season for the spring cohort (September/October 2026) or prior to the post-season study visit for the fall cohort (May/June 2027).
Written informed consent is obtained from all participants prior to study procedures. The study has been approved by the University of British Columbia Children's and Women's Research Ethics Board (H25-02623).
Study Procedures:
At enrollment, parents are asked to complete a baseline questionnaire that collects basic pregnancy information (e.g. maternal age, pregnancy conditions, number of babies in pregnancy), intention to receive or receipt of RSV maternal vaccine, household size / number of siblings at home and their ages, smoking, family history of asthma/use of inhalers, use of antibiotics during pregnancy, family history of atopy / asthma, presence of furry pets in the home.
In each post-season questionnaire, parents are also additionally asked about socioeconomic factors, travel, daycare use, child medication use, child hospitalization or medical visit for a respiratory infection and if their child experienced asthma or wheezing symptoms. Study staff review hospital charts at birth and each year after the respiratory season to gather information about RSV-related hospitalizations and RSV testing.
Parents complete a child feeding questionnaire at 3, 6 and 12 months to collect information on infant/child dietary intake including breastfeeding and formula use (start/end dates, duration) and introduction of solid foods.
Biospecimen Collection:
A cord blood sample collected at delivery. If cord blood cannot be collected, a peripheral blood sample is taken at a scheduled study visit within one month after birth, at BC Children's Hospital. If enrolled greater than 1 month after delivery, cord/peripheral blood is not collected. To account for pre-season RSV antibody levels in the analysis, an additional pre-season dried blood spot (DBS) sample are collected in September from the spring cohort babies. We also obtain a residual sample from the Newborn Screening DBS at birth in all infants, for measurements of RSV antibody levels and neutralization titers.
A post-season blood sample is collected from all participants at a scheduled study visit at BC Children's Hospital in May or June following the RSV season.
Serology samples are used to quantify RSV antibodies and neutralization titers, and RSV F-specific antibody-dependent function.
Cord blood and peripheral blood mononuclear cells are stored from the cord and post-natal blood samples, to measure RSV T and B cell responses. A sample is also stored for whole blood RNA-Sequencing studies (PAXgene).
Prenatal and delivery serology samples are obtained from routine samples collected from birthing parents. An additional maternal blood sample is collected at the scheduled post-season study visit in May or June 2027.
RSV Testing and Respiratory Outcome Questionnaires:
Infants are monitored for respiratory outcomes (wheezing episodes) throughout each RSV season (September to March) using parent-completed diaries and parent-collected nasal swab testing when child exhibit pre-defined symptom criteria for infection (e.g. fever, cough, nasal congestion, difficulty breathing).
A subset of infants who test positive for RSV during the acute illness are invited to provide a blood sample about 2 weeks into the acute illness.
Diaries will be used for parents to record each episode of a respiratory infection, the severity and duration of the episode, and to track wheezing days.
Microbiome Studies:
A subset of at least 50 birthing parents in each (Apri-Jun / Sept/Nov) group provide a self-collected vaginal swab within 2 weeks after birth.
Oral swabs are collected from the infants around 2 weeks of age. In addition, stool samples are collected on children at 3, 6, 9 and 12 months of age. For children recruited greater than 1 month after delivery, microbiome samples are not collected.
Main Outcomes:
The study sample size is determined based on the respiratory outcome at 3 years, using the Child Healthy Infant Longitudinal Development study has developed and validated the (CHILDhood Asthma Risk Tool) CHART tool.
The main post-season outcomes are RSV antibody levels and neutralization, with main comparisons between the spring and fall groups/cohorts.
- Conditions
- Respiratory Synctial Virus, Asthma Childhood
- Keywords
- cohort study, Immune response, infants, season of birth
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| 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) |
What is being measured
The primary outcome is the main question the study is designed to answer.
RSV antibody response
- 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
Measured: 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)
Measured: at age 3 years old
Secondary outcomes (2)
Medically attended RSV infections
Incidence of RSV and Lower Respiratory Tract Infection hospitalizations and medically attended RSV infections
Measured: At 1 year and 3 years of age
Wheezing
Proportion of infants who develop persistent wheezing after their first RSV episode, and the number of wheezing days during season, and after each episode of RSV infection.
Measured: During first RSV season (Sept to April), and each season, up to 3 years of age (for number of wheezing days during season).
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted17 Jun 2026
- Study start15 Jan 2026
- Primary completion1 Jun 2027 (estimated)
- Study completion1 Dec 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Respiratory Synctial VirusStudies of the same condition, open and under way.
- More trials run by University of British ColumbiaThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 300 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of British Columbia
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Pascal Lavoie, University of British Columbia
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07653347
- Sponsor's protocol ID
- F25-01060
- Acronym
- IRIS
- Status last verified
- Jun 2026
- First submitted
- 11 Jun 2026
- Last updated
- 17 Jun 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided: Pending approval by our local Research Ethics Board.
Study at a glance
From the registry record, last updated by the sponsor on 17 Jun 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Understanding the Impact of Early-life RSV Infections on Infant Immunity and Long-term Health
- ClinicalTrials.gov ID
- NCT07653347
- Acronym / sponsor ID
- IRIS / F25-01060
- Conditions
- Respiratory Synctial Virus, Asthma Childhood
- Keywords
- cohort study, Immune response, infants, season of birth
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 300 participants (estimated)
- Lead sponsor
- University of British ColumbiaUniversity, hospital or other
- Study start
- 15 Jan 2026 (actual)
- Primary completion
- 1 Jun 2027 (estimated)
- Study completion
- 1 Dec 2029 (estimated)
- First posted
- 17 Jun 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Detailed description
In British Columbia (Canada), RSV cases rise each year after mid-October, until April, peaking in December. This study compares outcomes between infants born in April to June, who will be naturally exposed to RSV >6-9 months of age versus infants born in September to November, who will be naturally exposed to RSV <4 months of age. Most infants become infected during their first RSV year.
Primary Objectives:
- Compare post-season RSV immune responses between the spring cohort of infants born in April to June versus the fall cohort of infants born in September to November.
- Compare respiratory outcomes at 3 years of age between the spring cohort of infants born in April to June versus the fall cohort of infants born in September to November.
Secondary Objectives:
- Identify immune maturation events linked to stronger post-season RSV antibody responses.
- Determine how the gut and upper airway microbiota co-evolve in infants over the first year of life, and how these dynamics shape RSV risk, and are shaped by host-related, and specifically seasonal factors (i.e. Apr-Jun versus Sept-Nov).
- Compare immune responses during acute RSV infections between the spring cohort of infants born in April to June versus the fall cohort of infants born in September to November.
Design:
Prospective, observational cohort study of 300 parent-infant pairs born in the spring (April-June) or fall (Sept-Nov), with follow-up at 3 years of age.
Recruitment and Informed Consent Procedure:
Birthing parents planning to give birth at the BC Women's Hospital or live locally in greater Vancouver are identified through the BC Women's Hospital prenatal ultrasound clinic or social media and contacted by the study coordinator in person, by telephone or by text message. Interested participants complete an online eligibility questionnaire and, if eligible, the online consent form. Study advertisements posted in the hospital, local clinics, local community centers and on social media direct interested parents to the study website, online eligibility questionnaire and the study coordinators contact information.
Patients who delivered an infant during the study eligibility period in the Vancouver Coastal Health region are also invited by mail and enrolled prior to the start of the respiratory season for the spring cohort (September/October 2026) or prior to the post-season study visit for the fall cohort (May/June 2027).
Written informed consent is obtained from all participants prior to study procedures. The study has been approved by the University of British Columbia Children's and Women's Research Ethics Board (H25-02623).
Study Procedures:
At enrollment, parents are asked to complete a baseline questionnaire that collects basic pregnancy information (e.g. maternal age, pregnancy conditions, number of babies in pregnancy), intention to receive or receipt of RSV maternal vaccine, household size / number of siblings at home and their ages, smoking, family history of asthma/use of inhalers, use of antibiotics during pregnancy, family history of atopy / asthma, presence of furry pets in the home.
In each post-season questionnaire, parents are also additionally asked about socioeconomic factors, travel, daycare use, child medication use, child hospitalization or medical visit for a respiratory infection and if their child experienced asthma or wheezing symptoms. Study staff review hospital charts at birth and each year after the respiratory season to gather information about RSV-related hospitalizations and RSV testing.
Parents complete a child feeding questionnaire at 3, 6 and 12 months to collect information on infant/child dietary intake including breastfeeding and formula use (start/end dates, duration) and introduction of solid foods.
Biospecimen Collection:
A cord blood sample collected at delivery. If cord blood cannot be collected, a peripheral blood sample is taken at a scheduled study visit within one month after birth, at BC Children's Hospital. If enrolled greater than 1 month after delivery, cord/peripheral blood is not collected. To account for pre-season RSV antibody levels in the analysis, an additional pre-season dried blood spot (DBS) sample are collected in September from the spring cohort babies. We also obtain a residual sample from the Newborn Screening DBS at birth in all infants, for measurements of RSV antibody levels and neutralization titers.
A post-season blood sample is collected from all participants at a scheduled study visit at BC Children's Hospital in May or June following the RSV season.
Serology samples are used to quantify RSV antibodies and neutralization titers, and RSV F-specific antibody-dependent function.
Cord blood and peripheral blood mononuclear cells are stored from the cord and post-natal blood samples, to measure RSV T and B cell responses. A sample is also stored for whole blood RNA-Sequencing studies (PAXgene).
Prenatal and delivery serology samples are obtained from routine samples collected from birthing parents. An additional maternal blood sample is collected at the scheduled post-season study visit in May or June 2027.
RSV Testing and Respiratory Outcome Questionnaires:
Infants are monitored for respiratory outcomes (wheezing episodes) throughout each RSV season (September to March) using parent-completed diaries and parent-collected nasal swab testing when child exhibit pre-defined symptom criteria for infection (e.g. fever, cough, nasal congestion, difficulty breathing).
A subset of infants who test positive for RSV during the acute illness are invited to provide a blood sample about 2 weeks into the acute illness.
Diaries will be used for parents to record each episode of a respiratory infection, the severity and duration of the episode, and to track wheezing days.
Microbiome Studies:
A subset of at least 50 birthing parents in each (Apri-Jun / Sept/Nov) group provide a self-collected vaginal swab within 2 weeks after birth.
Oral swabs are collected from the infants around 2 weeks of age. In addition, stool samples are collected on children at 3, 6, 9 and 12 months of age. For children recruited greater than 1 month after delivery, microbiome samples are not collected.
Main Outcomes:
The study sample size is determined based on the respiratory outcome at 3 years, using the Child Healthy Infant Longitudinal Development study has developed and validated the (CHILDhood Asthma Risk Tool) CHART tool.
The main post-season outcomes are RSV antibody levels and neutralization, with main comparisons between the spring and fall groups/cohorts.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| 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) |
Who may qualify
- Ages
- Up to 6 months
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Child
- 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.
Key inclusion criteria (1 listed)
- 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.
Key exclusion criteria (1 listed)
- 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).
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
RSV antibody response
Time frame: Post-respiratory season 2027 (May 2027)
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
Asthma symptoms
Time frame: at age 3 years old
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)
2 secondary outcomes
Medically attended RSV infections
Time frame: At 1 year and 3 years of age
Wheezing
Time frame: During first RSV season (Sept to April), and each season, up to 3 years of age (for number of wheezing days during season).
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 17 Jun 2026.
- Individual participant dataSharing planned: Undecided. Pending approval by our local Research Ethics Board.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Respiratory Synctial Virus and Asthma Childhood, run by University of British Columbia at 1 site in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 17 Jun 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Pascal Lavoie, MDCM PhD FRCPC (604-875-2135, plavoie@bcchr.ca), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
RSV antibody response (time frame: Post-respiratory season 2027 (May 2027)). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 17 Jun 2026; AzTrials last refreshed its copy on 27 Oct 2026.