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Published on: January 26, 2019
Nirsevimab and Hospitalization for RSV Bronchiolitis
Zein Assad1, Anne-Sophie Romain1, Camille Aupiais1
1From the Department of General Pediatrics, Pediatric Infectious Disease, and Internal Medicine (Z.A., A.G., N.O.), Centre d'Investigations Cliniques, INSERM Unité 1426 (Z.V.), the Pediatric Intensive Care Unit (M. Levy, P.S.), the Pediatric Emergency Department (L.L.), the Department of Microbiology (M.G.-M.), the Neonatal Intensive Care Unit (V.B.), and the Unit of Clinical Epidemiology, INSERM Unité 1123 and Epidémiologie Clinique du Centre d'Investigation Clinique 1426 (K.D., O.A.), Robert-Debré University Hospital, Paris Cité University (Z.A., C.S., A.G., Z.V., M.B., J.F.C., J.T., M.L., P.S., L.L., M.G.-M., V.B., K.D., O.A.), the Departments of General Pediatrics (A.-S.R., M. Lorrot, C.F.) and Pediatric Pulmonology (A.-S.R., M. Lorrot), Armand Trousseau University Hospital, Sorbonne University (A.-S.R., M. Lorrot), the Pediatric Emergency Department (C.S.), the Pediatric Intensive Care Unit (M.B.), and the Department of General Pediatrics and Pediatric Infectious Diseases (C.S., J.F.C., J.T.), Necker-Enfants Malades University Hospital, Saint-Antoine Research Center, INSERM Unité Mixte de Recherche (UMR) S938 (H.C., B.P.), and Assistance Publique-Hôpitaux de Paris (AP-HP), Infection, Antimicrobials, Modeling, and Evolution (IAME) Research Unit, INSERM UMR 1137 (Z.A., L.L., M.G.-M., N.O.), Épidémiologie Clinique et Évaluation Économique Appliqué aux Populations Vulnérables, INSERM UMR 1123 (C.A.), the Center of Research in Epidemiology and Statistics, INSERM UMR 1153 (J.F.C.), and Biodiversity and Epidemiology of Bacterial Pathogens Research Unit, Institut Pasteur (J.T.), Paris Cité University, Paris, Groupe de Pathologie Infectieuse Pédiatrique, Nice (Z.A., M. Lorrot, R.C., C.L., N.O.), the Pediatric Emergency Department (C.A.) and the Department of General Pediatrics (L.P., C.F.D.), Jean Verdier University Hospital, AP-HP de Paris, Bondy, the Department of General Pediatrics, Centre Hospitalier Intercommunal de Créteil (M.S., C.J.), Association Clinique et Thérapeutique Infantile du Val-de-Marne France (R.C., C.L.), Institut Mondor de Recherche Biomédicale-Groupe de Recherche Clinique Groupe d'Étude des Maladies Infectieuses Néonatales et Infantiles, Université Paris Est (R.C., C.L., C.J.), and the Clinical Research Center (M.M.E.H., C.J.) and the Neonatal Intensive Care Unit (X.D.), Centre Hospitalier Intercommunal de Créteil, Université Paris Est Créteil, Faculté de Santé de Créteil, Créteil, Association Française de Pédiatrie Ambulatoire, Orleans (R.C., C.L.), and the Departments of Pediatric Pulmonology and Allergology (G.L., N.C.) and General Pediatrics (B.H., O.M., C.B.), Children's Hospital, Toulouse University Hospital, Toulouse - all in France; and the Department of Pediatrics, Department Woman-Mother-Child, Lausanne University Hospital, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland (F.A.).
Background:
Respiratory syncytial virus (RSV) is the leading cause of bronchiolitis, resulting in 3 million hospitalizations each year worldwide. Nirsevimab is a monoclonal antibody against RSV that has an extended half-life. Its postlicensure real-world effectiveness against RSV-associated bronchiolitis is unclear.
Methods:
We conducted a prospective, multicenter, matched case-control study to analyze the effectiveness of nirsevimab therapy against hospitalization for RSV-associated bronchiolitis in infants younger than 12 months of age. Case patients were infants younger than 12 months of age who were hospitalized for RSV-associated bronchiolitis between October 15 and December 10, 2023. Control patients were infants with clinical visits to the same hospitals for conditions unrelated to RSV infection. Case patients were matched to control patients in a 2:1 ratio on the basis of age, date of hospital visit, and study center. We calculated the effectiveness of nirsevimab therapy against hospitalization for RSV-associated bronchiolitis (primary outcome) by means of a multivariate conditional logistic-regression model with adjustment for confounders. Several sensitivity analyses were performed.
Results:
The study included 1035 infants, of whom 690 were case patients (median age, 3.1 months; interquartile range, 1.8 to 5.3) and 345 were matched control patients (median age, 3.4 months; interquartile range, 1.6 to 5.6). Overall, 60 case patients (8.7%) and 97 control patients (28.1%) had received nirsevimab previously. The estimated adjusted effectiveness of nirsevimab therapy against hospitalization for RSV-associated bronchiolitis was 83.0% (95% confidence interval [CI], 73.4 to 89.2). Sensitivity analyses gave results similar to those of the primary analysis. The effectiveness of nirsevimab therapy against RSV-associated bronchiolitis resulting in critical care was 69.6% (95% CI, 42.9 to 83.8) (27 of 193 case patients [14.0%] vs. 47 of 146 matched control patients [32.2%]) and against RSV-associated bronchiolitis resulting in ventilatory support was 67.2% (95% CI, 38.6 to 82.5) (27 of 189 case patients [14.3%] vs. 46 of 151 matched control patients [30.5%]).
Conclusions:
In a real-world setting, nirsevimab therapy was effective in reducing the risk of hospitalized RSV-associated bronchiolitis. (Funded by the National Agency for AIDS Research-Emerging Infectious Disease and others; ENVIE ClinicalTrials.gov number, NCT06030505.).
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