RSVNCT06511687
Effectiveness And Impact Of Nirsevimab In Chile (NIRSE-CL)
An observational study of RSV, run by Instituto Sistemas Complejos de Ingeniería at 1 site in Chile.
Trial summary
The Nirse-CL study is a collaborative effort between the Ministry of Health of Chile, Instituto Sistemas Complejos de Ingeniería (ISCI), and the Faculty of Medicine of the University of Chile. Read more about this study
- Who is it for?
- Ages Up to 4 years
- Conditions the study is for
- RSV
- What is being tested?
- Nirsevimab
- How many people
- 160,000 participants
- Where
- 1 siteChile
- Study dates
- 1 Apr 2024to 1 Oct 2024
- Phase
- Observational
- Are there results?
- None posted in the registry
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 4 years
- All sexes
- No healthy volunteers
- Child
Study population: All infants born in Chile between October 1st, 2023, to September 31st, 2024 (approximately 160.000), and all high-risk infants born between July 1st, 2023, and October 1st, 2023 (approximately <1.000).
Who may be able to join
- Subjects born between October 1st, 2023, to September 31st, 2024.
- Subjects born with 29 weeks of gestational age (wga) or less who were born between July 1st, 2023 and October 1st, 2023
- Subjects born with Bronchopulmonary Dysplasia (BPD), 32 or less wga and/or a birth weight less than 1·5 kgs born between April 1st, 2023 and October 1st, 2023.
Who cannot join
- No specific criteria has been reported
Trial locations and contacts
1 site in 1 country.
Chile1 site, 1 recruiting
- Recruiting
ISCI
Santiago, 8370398
Leonardo Basso, 56 962295601, l.basso@isci.cl
About this study
Official title: Effectiveness And Impact of Nirsevimab In A Nationwide Immunization Program During The 2024 Winter Campaign In Chile (Nirse-CL)
The Nirse-CL study is a collaborative effort between the Ministry of Health of Chile, Instituto Sistemas Complejos de Ingeniería (ISCI), and the Faculty of Medicine of the University of Chile. The primary aim is to determine the effectiveness of the monoclonal antibody nirsevimab in preventing RSV infection in infants based on the integrated analysis of several national databases before, during, and after the implementation of a universal immunization program. The impact of the program on RSV-related health outcomes will also be determined.
Read the detailed description
The primary aim of NirseCL is to evaluate the effectiveness of nirsevimab against Respiratory Syncytial Virus (RSV) in infants during the 2024 RSV season in Chile. The secondary objective is to determine the impact on RSV-related health outcomes at a national level.
The target population to receive nirsevimab is approximately 160,000 subjects, including the entire newborn cohort born during the autumn-winter season, from April 1st, 2024, to September 31st, 2024, infants born from October 1st, 2023, to March 31st, 2024, which are 6 to 1 month old at the time of immunization in April-June, and the high-risk group defined as infants born with 29 weeks of gestational age (wga) or less who were born within nine months of the beginning of the RSV season; those born with Bronchopulmonary Dysplasia (BPD), 32 or less wga and/or a birth weight less than 1·5 kgs born within one year of the beginning of the RSV season, and newborns 34 or less wga and/or weight less than 2·5 kgs born during the RSV season.
Nirsevimab will be administered as part of Chile's national immunization program, following the implementation plan designed by the Ministry of Health. The coverage with nirsevimab in the target population is expected to be high (95% for those born during the winter campaign and 80% for those born before the beginning of the autumn-winter season).
The primary outcome measure for effectiveness will be lower-tract respiratory infection hospitalizations (LRTI) attributed to RSV in the pediatric intensive care units (PICU) at a nationwide and regional level, and the secondary outcomes will be overall LRTI hospitalizations attributed to RSV, LRTI hospitalizations, and hospitalizations due to any cause. Additional outcomes might be included if enough statistical power is attained.
Effectiveness will be determined using a two-step process. First, historical data will be used to determine the set of ICD10 diagnosis codes that are attributable to RSV infection by using data from the Chilean national sentinel program and consolidated hospitalization records. Afterward, A series of complementary statistical analyses at different aggregation levels will be conducted to estimate the impact of nirsevimab on the target population. Detailed patient-level information will be used to compare LRTI hospitalizations of those receiving the immunization against those who did not, using an adjusted proportional hazard rates regression model to estimate the effectiveness of nirsevimab as a function of covariates such as wga, weight at birth, sex, nationality, maternal education, coexisting conditions, MMR vaccination (as an indicator of access to medical care), and place of birth. This method has been used to evaluate recent nationwide vaccination campaigns in Chile (Jara et al, 2021). A case-control matching approach will be used as an alternative method intended to gain statistical efficiency (Rose and van der Laan, 2009). Finally, as a robustness analysis, a synthetic control method that allows the comparison of whole time series without relying on individual-level data will be used (Bruhn et al., 2016).
- Conditions
- RSV
- Being tested
- Nirsevimab
- Keywords
- RSV, Nirsevimab
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
NirsevimabBiological
Also called Beyfortus
Nirsevimab will be administered in a single dose at birth for newborn cohort and at the beginning of the campaign for the other cohorts under study
| Study group | Role | What they receive |
|---|---|---|
| Newborns | Subjects born between April 1st, and September 31st in 2024 Receives: Biological: Nirsevimab | |
| Catch-up | Subjects born between October 1st of 2023 and March 31st of 2024 Receives: Biological: Nirsevimab | |
| High-risk | High-Risk Cohort: Infants born with 29 weeks of gestational age (wga) or less who were born within nine months of the beginning of the RSV season; those born with Bronchopulmonary Dysplasia (BPD), 32 or less wga and/or a birth weight less than 1·5 kgs born within one year of the beginning of the RSV season, and newborns 34 or less wga and/or weight less than 2·5 kgs born during the RSV season. Receives: Biological: Nirsevimab |
What is being measured
The primary outcome is the main question the study is designed to answer.
LRTI
Number and incidence of lower-tract respiratory infections hospitalizations (LRTI) attributed to RSV in the pediatric intensive care units (PICU) at a nationwide and regional level.
Measured: from April 2024 to October 2024
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 Jul 2024
- Study start1 Apr 2024
- Primary completion1 Oct 2024 (estimated)
- Study completion1 Oct 2024 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (5)Papers the sponsor has linked to this study.
- Other trials for RSVStudies of the same condition, open and under way.
- 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
- Retrospective
- Enrolment
- 160,000 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Instituto Sistemas Complejos de Ingeniería
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06511687
- Sponsor's protocol ID
- ISCI00000001
- Status last verified
- Jul 2024
- First submitted
- 9 Jul 2024
- Last updated
- 22 Jul 2024
- Results posted
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
Publications
Rose S, Laan MJ. Why match? Investigating matched case-control study designs with causal effect estimation. Int J Biostat. 2009 Jan 6;5(1):Article 1. doi: 10.2202/1557-4679.1127.
PubMed 20231866Martens L, Leroy R, Jara A, Garcia-Zattera MJ, Lesaffre E, Declerck D. Variables associated with longitudinally registered plaque accumulation in a cohort of Flemish schoolchildren. Quintessence Int. 2007 Jul-Aug;38(7):555-64.
PubMed 17694211Bruhn CA, Hetterich S, Schuck-Paim C, Kurum E, Taylor RJ, Lustig R, Shapiro ED, Warren JL, Simonsen L, Weinberger DM. Estimating the population-level impact of vaccines using synthetic controls. Proc Natl Acad Sci U S A. 2017 Feb 14;114(7):1524-1529. doi: 10.1073/pnas.1612833114. Epub 2017 Feb 1.
PubMed 28154145Pearce N. Analysis of matched case-control studies. BMJ. 2016 Feb 25;352:i969. doi: 10.1136/bmj.i969.
PubMed 26916049Torres JP, Saure D, Goic M, Thraves C, Pacheco J, Burgos J, Trigo N, Del Solar F, Neira I, Diaz G, O'Ryan M, Basso LJ. Effectiveness and impact of nirsevimab in Chile during the first season of a national immunisation strategy against RSV (NIRSE-CL): a retrospective observational study. Lancet Infect Dis. 2025 Nov;25(11):1189-1198. doi: 10.1016/S1473-3099(25)00233-6. Epub 2025 Jun 10.
PubMed 40513593
Study at a glance
From the registry record, last updated by the sponsor on 22 Jul 2024. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effectiveness And Impact of Nirsevimab In A Nationwide Immunization Program During The 2024 Winter Campaign In Chile (Nirse-CL)
- ClinicalTrials.gov ID
- NCT06511687
- Acronym / sponsor ID
- ISCI00000001
- Conditions
- RSV
- Keywords
- RSV, Nirsevimab
- Study type
- Observational
- Recruitment status
- Unknown status
- Enrolment
- 160,000 participants (estimated)
- Lead sponsor
- Instituto Sistemas Complejos de IngenieríaUniversity, hospital or other
- Study start
- 1 Apr 2024 (actual)
- Primary completion
- 1 Oct 2024 (estimated)
- Study completion
- 1 Oct 2024 (estimated)
- First posted
- 22 Jul 2024 (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.
The Nirse-CL study is a collaborative effort between the Ministry of Health of Chile, Instituto Sistemas Complejos de Ingeniería (ISCI), and the Faculty of Medicine of the University of Chile. The primary aim is to determine the effectiveness of the monoclonal antibody nirsevimab in preventing RSV infection in infants based on the integrated analysis of several national databases before, during, and after the implementation of a universal immunization program. The impact of the program on RSV-related health outcomes will also be determined.
Detailed description
The primary aim of NirseCL is to evaluate the effectiveness of nirsevimab against Respiratory Syncytial Virus (RSV) in infants during the 2024 RSV season in Chile. The secondary objective is to determine the impact on RSV-related health outcomes at a national level.
The target population to receive nirsevimab is approximately 160,000 subjects, including the entire newborn cohort born during the autumn-winter season, from April 1st, 2024, to September 31st, 2024, infants born from October 1st, 2023, to March 31st, 2024, which are 6 to 1 month old at the time of immunization in April-June, and the high-risk group defined as infants born with 29 weeks of gestational age (wga) or less who were born within nine months of the beginning of the RSV season; those born with Bronchopulmonary Dysplasia (BPD), 32 or less wga and/or a birth weight less than 1·5 kgs born within one year of the beginning of the RSV season, and newborns 34 or less wga and/or weight less than 2·5 kgs born during the RSV season.
Nirsevimab will be administered as part of Chile's national immunization program, following the implementation plan designed by the Ministry of Health. The coverage with nirsevimab in the target population is expected to be high (95% for those born during the winter campaign and 80% for those born before the beginning of the autumn-winter season).
The primary outcome measure for effectiveness will be lower-tract respiratory infection hospitalizations (LRTI) attributed to RSV in the pediatric intensive care units (PICU) at a nationwide and regional level, and the secondary outcomes will be overall LRTI hospitalizations attributed to RSV, LRTI hospitalizations, and hospitalizations due to any cause. Additional outcomes might be included if enough statistical power is attained.
Effectiveness will be determined using a two-step process. First, historical data will be used to determine the set of ICD10 diagnosis codes that are attributable to RSV infection by using data from the Chilean national sentinel program and consolidated hospitalization records. Afterward, A series of complementary statistical analyses at different aggregation levels will be conducted to estimate the impact of nirsevimab on the target population. Detailed patient-level information will be used to compare LRTI hospitalizations of those receiving the immunization against those who did not, using an adjusted proportional hazard rates regression model to estimate the effectiveness of nirsevimab as a function of covariates such as wga, weight at birth, sex, nationality, maternal education, coexisting conditions, MMR vaccination (as an indicator of access to medical care), and place of birth. This method has been used to evaluate recent nationwide vaccination campaigns in Chile (Jara et al, 2021). A case-control matching approach will be used as an alternative method intended to gain statistical efficiency (Rose and van der Laan, 2009). Finally, as a robustness analysis, a synthetic control method that allows the comparison of whole time series without relying on individual-level data will be used (Bruhn et al., 2016).
Study design
- Observational model
- Cohort
- Time perspective
- Retrospective
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Newborns | – | Biological: NirsevimabSubjects born between April 1st, and September 31st in 2024 |
| Catch-up | – | Biological: NirsevimabSubjects born between October 1st of 2023 and March 31st of 2024 |
| High-risk | – | Biological: NirsevimabHigh-Risk Cohort: Infants born with 29 weeks of gestational age (wga) or less who were born within nine months of the beginning of the RSV season; those born with Bronchopulmonary Dysplasia (BPD), 32 or less wga and/or a birth weight less than 1·5 kgs born within one year of the beginning of the RSV season, and newborns 34 or less wga and/or weight less than 2·5 kgs born during the RSV season. |
Who may qualify
- Ages
- Up to 4 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child
- Study population
- All infants born in Chile between October 1st, 2023, to September 31st, 2024 (approximately 160.000), and all high-risk infants born between July 1st, 2023, and October 1st, 2023 (approximately <1.000).
Key inclusion criteria (3 listed)
- Subjects born between October 1st, 2023, to September 31st, 2024.
- Subjects born with 29 weeks of gestational age (wga) or less who were born between July 1st, 2023 and October 1st, 2023
- Subjects born with Bronchopulmonary Dysplasia (BPD), 32 or less wga and/or a birth weight less than 1·5 kgs born between April 1st, 2023 and October 1st, 2023.
Key exclusion criteria (1 listed)
- No specific criteria has been reported
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| NirsevimabAlso: BeyfortusNirsevimab will be administered in a single dose at birth for newborn cohort and at the beginning of the campaign for the other cohorts under study | Biological | Catch-up, High-risk, Newborns |
Primary outcome
LRTI
Time frame: from April 2024 to October 2024
Number and incidence of lower-tract respiratory infections hospitalizations (LRTI) attributed to RSV in the pediatric intensive care units (PICU) at a nationwide and regional level.
Results and safety
Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 22 Jul 2024.
- Background: PubMed 20231866Rose S, Laan MJ. Why match? Investigating matched case-control study designs with causal effect estimation. Int J Biostat. 2009 Jan 6;5(1):Article 1. doi: 10.2202/1557-4679.1127.
- Background: PubMed 17694211Martens L, Leroy R, Jara A, Garcia-Zattera MJ, Lesaffre E, Declerck D. Variables associated with longitudinally registered plaque accumulation in a cohort of Flemish schoolchildren. Quintessence Int. 2007 Jul-Aug;38(7):555-64.
- Background: PubMed 28154145Bruhn CA, Hetterich S, Schuck-Paim C, Kurum E, Taylor RJ, Lustig R, Shapiro ED, Warren JL, Simonsen L, Weinberger DM. Estimating the population-level impact of vaccines using synthetic controls. Proc Natl Acad Sci U S A. 2017 Feb 14;114(7):1524-1529. doi: 10.1073/pnas.1612833114. Epub 2017 Feb 1.
- Background: PubMed 26916049Pearce N. Analysis of matched case-control studies. BMJ. 2016 Feb 25;352:i969. doi: 10.1136/bmj.i969.
- Derived from this study: PubMed 40513593Torres JP, Saure D, Goic M, Thraves C, Pacheco J, Burgos J, Trigo N, Del Solar F, Neira I, Diaz G, O'Ryan M, Basso LJ. Effectiveness and impact of nirsevimab in Chile during the first season of a national immunisation strategy against RSV (NIRSE-CL): a retrospective observational study. Lancet Infect Dis. 2025 Nov;25(11):1189-1198. doi: 10.1016/S1473-3099(25)00233-6. Epub 2025 Jun 10.
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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. This study is not recruiting at the moment.
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 RSV, run by Instituto Sistemas Complejos de Ingeniería at 1 site in Chile.
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 3 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: status not confirmed, as of the sponsor's last update on 22 Jul 2024. 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 Chile. 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?
Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
Contact Leonardo Basso, PhD in Business Administration (56 962295601, l.basso@isci.cl), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
LRTI (time frame: from April 2024 to October 2024). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT06511687, which also lists 5 linked publications.
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 22 Jul 2024.