FDA and EMA approve first vaccine for pregnant women to prevent RSV infection in infants, as well as new drug to prevent RSV infection in infants
In July/August 2023, the Food and Drug Administration (FDA) and the European Medicines Agency (EMA) approved Abrysvo®, the first respiratory syncytial virus (RSV) vaccine to gain approval for use in pregnant women to prevent RSV infection in infants. It is a bivalent RSV prefusion F (RSVpreF) protein-based vaccine for use at 32 to 36 weeks' gestational age of pregnancy, to prevent RSV in infants up to 6 months of age. It was proven to be effective with a favorable safety profile in large randomized controlled trials. The vaccine had previously also been recently approved for the prevention of lower respiratory tract diseases caused by RSV in individuals 60 years and older.
This comes after the approval of the immunoprophylactic drug nirsevimab to prevent RSV infection in infants and children. Nirsevimab is an RSV F protein-directed fusion inhibitor monoclonal antibody and has an advantage over current immunoprophylaxis options because it is longer acting and only requires one dose. The safety and efficacy of nirsevimab were supported by three clinical trials. In July 2023, the Center for Disease Control and Prevention's Advisory Committee on Immunization Practices (ACIP) recommended that infants ages <8 months born during or entering their first RSV season, and infants and children ages 8-19 months who are at increased risk of severe RSV disease and entering their second RSV season, receive one intramuscular dose of nirsevimab.
Together, these medications represent a breakthrough in preventing RSV infection. The Center for Disease Control and Prevention (CDC) estimates that 2% to 3% of children under 12 months of age in the US are hospitalized each year due to RSV. The CDC also estimates that 60,000 to 160,000 older adults in the US are hospitalized each year due to RSV infections, and approximately 6000 to 10,000 older adults die each year from RSV-related illness.
Summary
Definition
Respiratory syncytial virus (RSV) is a member of the Pneumoviridae family. It is the most common cause of bronchiolitis.
Symptoms of bronchiolitis include rhinorrhea, cough, wheeze, respiratory distress, and hypoxemia.[1] RSV can also cause pneumonia in children and, rarely, in immunocompetent adults.[Figure caption and citation for the preceding image starts]: Electron micrograph revealing the morphologic traits of the RSVCDC/Palmer EL; used with permission [Citation ends].
History and exam
Key diagnostic factors
- exposure to RSV
- infants at high risk for RSV infection
- winter season
- older adult age
- immune deficit
- rhinorrhea/congestion
- tachypnea
- increased work of breathing
- cough
- wheeze
- poor feeding
- cyanosis
- rales
- apnea
Other diagnostic factors
- fever
Risk factors
- exposure to RSV
- hemodynamically significant congenital heart disease
- history of prematurity
- immune deficit
- chronic lung disease
- high-risk infants with no recent immunoprophylaxis against RSV
- infants aged <6 months
- winter season
- older adult age
- smoke exposure
- family history of asthma
- Down syndrome
Diagnostic investigations
1st investigations to order
- pulse oximetry
Investigations to consider
- chest x-ray
- hydration status
- direct fluorescent antibody staining of respiratory specimen (e.g., nasopharyngeal aspirate)
- reverse transcriptase polymerase chain reaction of respiratory specimen (e.g., nasopharyngeal aspirate)
- viral culture of respiratory specimen (e.g., nasopharyngeal aspirate)
Treatment algorithm
mild or self-limited illness
moderate illness
severe illness
Contributors
Authors
Giovanni Piedimonte, MD, FAAP, FCCP
Vice President for Research
Professor of Pediatrics, Biochemistry, & Molecular Biology
Tulane University School of Medicine
New Orleans
LA
Disclosures
GP declares that he has no competing interests.
Margot Anderson, MD
Assistant Professor of Clinical Pediatrics
Section of Infectious Diseases and Hospital Medicine
Tulane University School of Medicine
Tulane University
New Orleans
LA
Disclosures
MA will be the principal investigator for a phase 3 trial to evaluate the safety, efficacy, and pharmacokinetics of MK-1654 in infants and children at increased risk for severe respiratory syncytial virus disease, based at Tulane University School of Medicine. Merck will reimburse Tulane University for participation.
Acknowledgements
Dr Giovanni Piedimonte and Dr Margot Anderson would like to gratefully acknowledge Dr Frank Esper and Dr Melvin L. Wright, previous contributors to this topic.
Disclosures
FE is on an advisory board for Procter and Gamble. MLW declares that he has no competing interests.
Peer reviewers
Leonard R. Krilov, MD
Chief
Pediatric Infectious Disease
Vice Chairman
Department of Pediatrics
Children's Medical Center
Winthrop University Medical Center
Mineola
Professor of Pediatrics
School of Medicine
Stony Brook University Medical Center
Stony Brook
NY
Disclosures
LRK has participated as an investigator in multiple clinical research trials supported by grants from MedImmune. LRK has also served as a consultant to MedImmune on medical advisory boards and is a member of their speakers' bureau.
Robert Welliver, MD
Professor of Pediatrics
Women and Children's Hospital
Buffalo
NY
Disclosures
RW declares that he has no competing interests.
Jennifer Handforth, MB ChB, MRCPCH, DTM&H
Consultant Paediatrician
Croydon University Hospital
Croydon
UK
Disclosures
JH declares that she has no competing interests.
Differentials
- Human metapneumovirus
- Influenza virus
- Parainfluenza virus
More DifferentialsGuidelines
- Bronchiolitis in children: diagnosis and management
- Australasian bronchiolitis guideline
More GuidelinesPatient leaflets
Bronchiolitis
Asthma in children
More Patient leaflets
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