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Nirsevimab Effectiveness Against Rsv Hospital Admission in Children Under 1 Year of Age: A Spanish Population-Based Case Control Study

28 Pages Posted: 15 Aug 2024

See all articles by Olivier Nuñez

Olivier Nuñez

Carlos III Institute of Health

Carmen Olmedo

Madrid Ministry of Health - Vaccines Division

David Moreno-Perez

Regional University Hospital – IBIMA

Nicola Lorusso

Consejería de Sanidad - Dirección General de Salud Pública

Sergio Fernández Martínez

Subdirectorate of Epidemiology and Public Health Surveillance

Pedro Eliseo Pastor Villalba

Subdirectorate of Epidemiology and Public Health Surveillance

Ángeles Gutierrez

Consejería de Sanidad - Dirección General de Salud Pública

Marcos Alonso-García

Health Services Research Network in Chronic Diseases (REDISSEC)

Pello Latasa

Department of Health

Rosa Sancho

Department of Health

Jacobo Mendioroz Peña

Generalitat de Catalunya

Montse Martinez-Marcos

Generalitat de Catalunya - Department of Health

Enriqueta Muñoz Platón

Consejería de Sanidad - Dirección General de Salud Pública

María Victoria García Rivera

Madrid Ministry of Health - General Directorate of Public Health

Olaia Pérez-Martínez

Public Health Directorate

Rosa María Álvarez-Gil

Public Health Directorate

Eva Rivas Wagner

Canary Islands Health Service

Nieves López Gonzalez-Coviella

Canary Islands Health Service

Matilde Zornoza

Public Health Directorate

M. Isabel Barranco

Public Health Directorate

María del Carmen Pacheco Martínez

Madrid Ministry of Health - General Directorate of Public Health

Virginia Álvarez Río

Madrid Ministry of Health - General Directorate of Public Health

Miguel Fiol Jaume

Hospital Universitari Son Espases

Roxana Morey Arance

Hospital Universitari Son Espases

Begoña Adiego Sancho

Madrid Ministry of Health - General Directorate of Public Health

Manuel Mendez Diaz

Madrid Ministry of Health - General Directorate of Public Health

Noa Batalla

Consejería de Sanidad - Dirección General de Salud Pública

Cristina Andreu

Consejería de Sanidad - Dirección General de Salud Pública

Jesús Castilla

Instituto de Salud Pública y Laboral de Navarra

Manuel Garcia Cenoz

Consejería de Sanidad - Dirección General de Salud Pública

Ana Fernández Ibáñez

Consejería de Sanidad - Dirección General de Salud Pública

Marta Huerta Huerta

Consejería de Sanidad - Dirección General de Salud Pública

Ana Carmen Ibañez

Consejería de Sanidad - Dirección General de Salud Pública

Belén Berradre Sáenz

Consejería de Sanidad - Dirección General de Salud Pública

Joaquín Lamas

University Hospital of Melilla

Luisa Hermoso

University Hospital of Melilla

Susana Casado Cobo

Consejería de Sanidad - Dirección General de Salud Pública

Manuel Galán Cuesta

Consejería de Sanidad - Dirección General de Salud Pública

Sara Montenegro

University Hospital of Ceuta

María Domínguez

University Hospital of Ceuta

Inma Jarrin

Carlos III Institute of Health - National Center for Epidemiology

Aurora Limia

Consejería de Sanidad - Dirección General de Salud Pública

Roberto Pastor-Barriuso

Carlos III Health Institute

Susana Monge

Carlos III Institute of Health - Communicable Diseases Department

More...

Abstract

Background: Respiratory Syncytial Virus (RSV) causes substantial morbidity in infants <1 year. In October 2023, Spain recommended the monoclonal antibody nirsevimab to all children born since 1 April 2023, at birth or as catch-up if born before October 2023. We estimated nirsevimab effectiveness in preventing RSV hospitalisations during the 2023-24 season.


Methods: We conducted a nationwide population-based matched case-control study. Cases were children hospitalised for lower respiratory tract infection who were RSV PCR-positive. For each case, four population-density controls born in the same province and date (±2 days) were selected. We defined at-birth immunisation as receiving nirsevimab during the first 2 weeks of life, and catch-up immunisation within 30 days from campaign onset. Causal intention-to-treat (ITT) and per-protocol (PP) effectiveness was estimated using inverse-probability-of-immunisation weighted conditional logistic regression.

Findings: We included 427 cases and 1707 controls in catch-up and 606 cases and 2421 controls in at-birth immunisation studies. Effectiveness in preventing RSV hospitalisations (95% confidence interval) for catch-up immunisation was 71% (65-77%) by ITT and 81% (76-85%) PP. Effectiveness for at-birth immunisation was 80% (76-84%) by ITT and 84% (80-87%) PP. Effectiveness was similar for ICU admission and need of mechanical ventilation, as well as by RSV subgroup. Children born pre-term or with birthweight <2500 g showed lower PP effectiveness, of about 70%.

Interpretation: Population-level nirsevimab immunoprophylaxis in children born or entering their first RSV season was very effective in preventing RSV hospitalisations, ICU admission and mechanical ventilation, with reduced but still high effectiveness for pre-term and low-birthweight children. 

Funding: Institute of Health Carlos III (own budget).

Declaration of Interest: Matilde Zornoza Moreno has received research grants, travel grants and speaking fees from Sanofi and Astra-Zeneca. All other authors declare no conflict of interest.

Ethical Approval: Ethical approval was granted by the Medicines Research Ethics Regional Committee of the Community of Madrid (EV_NIRSEV_V2). The full study protocol is available in Spanish.

Keywords: Respiratory Syncytial Virus, Hospitalization, Nirsevimab, effectiveness, Observational Study.

Suggested Citation

Nuñez, Olivier and Olmedo, Carmen and Moreno-Perez, David and Lorusso, Nicola and Fernández Martínez, Sergio and Pastor Villalba, Pedro Eliseo and Gutierrez, Ángeles and Alonso-García, Marcos and Latasa, Pello and Sancho, Rosa and Mendioroz Peña, Jacobo and Martinez-Marcos, Montse and Muñoz Platón, Enriqueta and García Rivera, María Victoria and Pérez-Martínez, Olaia and Álvarez-Gil, Rosa María and Rivas Wagner, Eva and López Gonzalez-Coviella, Nieves and Zornoza, Matilde and Barranco, M. Isabel and Pacheco Martínez, María del Carmen and Álvarez Río, Virginia and Fiol Jaume, Miguel and Morey Arance, Roxana and Adiego Sancho, Begoña and Mendez Diaz, Manuel and Batalla, Noa and Andreu, Cristina and Castilla, Jesús and Garcia Cenoz, Manuel and Fernández Ibáñez, Ana and Huerta Huerta, Marta and Ibañez, Ana Carmen and Berradre Sáenz, Belén and Lamas, Joaquín and Hermoso, Luisa and Casado Cobo, Susana and Galán Cuesta, Manuel and Montenegro, Sara and Domínguez, María and Jarrin, Inma and Limia, Aurora and Pastor-Barriuso, Roberto and Monge, Susana, Nirsevimab Effectiveness Against Rsv Hospital Admission in Children Under 1 Year of Age: A Spanish Population-Based Case Control Study. Available at SSRN: https://ssrn.com/abstract=4925473

Olivier Nuñez

Carlos III Institute of Health ( email )

c/ Monforte de Lemos 5
Madrid, Madrid 28029
Spain

Carmen Olmedo

Madrid Ministry of Health - Vaccines Division ( email )

Madrid
Spain

David Moreno-Perez

Regional University Hospital – IBIMA ( email )

Nicola Lorusso

Consejería de Sanidad - Dirección General de Salud Pública ( email )

Sergio Fernández Martínez

Subdirectorate of Epidemiology and Public Health Surveillance ( email )

Pedro Eliseo Pastor Villalba

Subdirectorate of Epidemiology and Public Health Surveillance ( email )

Ángeles Gutierrez

Consejería de Sanidad - Dirección General de Salud Pública ( email )

Marcos Alonso-García

Health Services Research Network in Chronic Diseases (REDISSEC) ( email )

Spain

Pello Latasa

Department of Health ( email )

Rosa Sancho

Department of Health ( email )

Jacobo Mendioroz Peña

Generalitat de Catalunya ( email )

Montse Martinez-Marcos

Generalitat de Catalunya - Department of Health ( email )

Barcelona
Spain

Enriqueta Muñoz Platón

Consejería de Sanidad - Dirección General de Salud Pública ( email )

María Victoria García Rivera

Madrid Ministry of Health - General Directorate of Public Health ( email )

Olaia Pérez-Martínez

Public Health Directorate ( email )

Rosa María Álvarez-Gil

Public Health Directorate ( email )

Eva Rivas Wagner

Canary Islands Health Service ( email )

Nieves López Gonzalez-Coviella

Canary Islands Health Service ( email )

Matilde Zornoza

Public Health Directorate ( email )

M. Isabel Barranco

Public Health Directorate ( email )

María del Carmen Pacheco Martínez

Madrid Ministry of Health - General Directorate of Public Health ( email )

Virginia Álvarez Río

Madrid Ministry of Health - General Directorate of Public Health ( email )

Miguel Fiol Jaume

Hospital Universitari Son Espases ( email )

Spain

Roxana Morey Arance

Hospital Universitari Son Espases ( email )

Spain

Begoña Adiego Sancho

Madrid Ministry of Health - General Directorate of Public Health ( email )

Manuel Mendez Diaz

Madrid Ministry of Health - General Directorate of Public Health ( email )

Noa Batalla

Consejería de Sanidad - Dirección General de Salud Pública ( email )

Cristina Andreu

Consejería de Sanidad - Dirección General de Salud Pública ( email )

Jesús Castilla

Instituto de Salud Pública y Laboral de Navarra ( email )

Spain

Manuel Garcia Cenoz

Consejería de Sanidad - Dirección General de Salud Pública ( email )

Ana Fernández Ibáñez

Consejería de Sanidad - Dirección General de Salud Pública ( email )

Marta Huerta Huerta

Consejería de Sanidad - Dirección General de Salud Pública ( email )

Ana Carmen Ibañez

Consejería de Sanidad - Dirección General de Salud Pública ( email )

Belén Berradre Sáenz

Consejería de Sanidad - Dirección General de Salud Pública ( email )

Joaquín Lamas

University Hospital of Melilla ( email )

Luisa Hermoso

University Hospital of Melilla ( email )

Susana Casado Cobo

Consejería de Sanidad - Dirección General de Salud Pública ( email )

Manuel Galán Cuesta

Consejería de Sanidad - Dirección General de Salud Pública ( email )

Sara Montenegro

University Hospital of Ceuta ( email )

María Domínguez

University Hospital of Ceuta ( email )

Inma Jarrin

Carlos III Institute of Health - National Center for Epidemiology ( email )

Aurora Limia

Consejería de Sanidad - Dirección General de Salud Pública ( email )

Roberto Pastor-Barriuso

Carlos III Health Institute ( email )

Spain

Susana Monge (Contact Author)

Carlos III Institute of Health - Communicable Diseases Department ( email )

Madrid
Spain