Real-World Effectiveness of Perinatal RSV Immunoprophylaxis
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Nirsevimab.
- Who it may be relevant to
- Registry conditions: RSV Infection. Basic parameters: up to 12 months · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- United States
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Overview
The purpose of this study is to continue evaluating how well the RSV vaccines work as they are currently being used in routine clinical practice. Some of the questions that the investigators hope to answer with this study are: 1) What is the overall effectiveness of these vaccines? 2) How long does immunity last? 3) How effective are the vaccines against new strains? 3) Does the vaccine's effectiveness vary by age?
Detailed description
This will be a large-scale case-control study aiming to evaluate the effectiveness of perinatal RSV immunoprophylaxis. Cases and controls will be identified using active surveillance in both inpatient and outpatient clinical sites of the Yale New Haven Health System. Investigators will enroll patients seeking health care for acute respiratory illness and confirm RSV infection using approved molecular assays. Data will be collected from multiple sources, including health records, interviews, immunization registries, and population-based surveys. Investigators will generate estimates of effectiveness for each type of immunization used, disaggregated by time from immunization, disease severity, and sociodemographic characteristics (Aim 1). Investigators will also perform genetic characterization of all RSV viruses in the study, monitor the genetic diversity of the virus over time, and quantify the relative effectiveness of immunoprophylaxis against various viral lineages (Aim 2). Finally, investigators will collect acute and convalescent blood from a subset of infants and employ a single-cell and multi-omics approach to study the dynamics of the innate and adaptive immune responses during RSV infection and explore the molecular mechanisms that contribute to immunoprophylaxis failure (Aim 3).
Interventions
- Drug Nirsevimab
Immunoprophylaxis against RSV
Primary outcome measures
- Overall effectiveness of RSV immunoprophylaxis [Time frame: Up to 5 years]
Secondary outcome measures (2)
- Relative effectiveness of RSV immunoprophylaxis by viral groups or clades. [Time frame: Up to 5 years]
- Kinetics of the innate and adaptive immune responses [Time frame: Up to 5 years]
Eligibility criteria
Inclusion criteria
- ≤ 12 months of age at the time of presentation for evaluation for an acute respiratory infection (ARI).
- Documentation of an ARI, which is defined as an acute onset (<10 days) illness that includes: At least two of the following symptoms: fever (measured or subjective), chills, rigors, myalgia, headache, sore throat, nausea or vomiting, diarrhea, fatigue, congestion OR any one of the following: cough, shortness of breath, difficulty breathing, olfactory disorder, taste disorder, confusion, persistent chest pain, pale, gray, hypoxia, clinical or radiographic evidence of pneumonia or respiratory distress syndrome.
- Residents of Connecticut
Exclusion criteria
- Illness duration of >10 days at the time of respiratory specimen collection, measured from the date of the first symptom of the current acute illness.
- Parents/guardians are not able to provide informed consent
To be eligible for inclusion in the study as a healthy control, an individual must meet all of the following criteria:
- Immunized against RSV ≤ 12 months of age
- Residents of Connecticut
- Match an enrolled case that was a vaccine failure by date of birth (±1 month), sex, and immunoprophylactic agent received (i.e., maternal vaccine vs mAb).
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Observational model
- Case-control
Study locations
United States · 1 center
- Yale Child Health Research Center — New Haven
Publications
- Aparicio Llorente C, Wats A, Araujo BL, Moniz Ganem J, Oliva IO, Xu H, Brodsky NN, Lucas CL, Aronson PL, Grubaugh ND, Breban M, Redmond S, Shapiro ED, Niccolai LM, Weinberger DM, Oliveira CR. Real-world effectiveness of perinatal RSV immunoprophylaxis: protocol for a test-negative case-control study. BMJ Open. 2026 Mar 19;16(3):e114524. doi: 10.1136/bmjopen-2025-114524. PMID 41856594
Identifiers
NCT: NCT06172660 · 2000036550 · 1R01AI179874-01