Tools for Practice Outils pour la pratique

#361 Preventing RSV Infections in Infants

How safe and effective are monoclonal antibodies to prevent respiratory syncytial virus (RSV) infections in infants?

In high-risk infants (premature and/or congenital heart or lung conditions), palivizumab (4-5 doses monthly during RSV season) reduces RSV hospitalization (4.5% versus 10% placebo).  Nirsevimab (one dose) reduces RSV hospitalizations in healthy premature infants (0.8% versus 4%) and term infants (0.3-0.4% versus 1.5-2.0%). Side effects are similar to placebo.

CFPCLearn Logo

Reading Tools for Practice Article can earn you MainPro+ Credits

La lecture d'articles d'outils de pratique peut vous permettre de gagner des crédits MainPro+

Join Now S’inscrire maintenant

Already a CFPCLearn Member? Log in

Déjà abonné à CMFCApprendre? Ouvrir une session

  • From highest quality systematic review or key randomized controlled trials (RCTs). Comparisons statistically different unless indicated.
  • Palivizumab: 4-5 doses monthly during RSV season;
    • Systematic review (5 RCTs, 3443 infants)1 with two dominant placebo-controlled RCTs: Infants born <35 weeks or with bronchopulmonary dysplasia2 or congenital heart disease.3 At two years:
      • RSV hospitalization: 4.4% versus 9.8% (placebo), relative risk reduction (RRR)=55%; number needed to vaccinate (NNV)=19.
      • Mortality: 1.3% versus 2.3% placebo (not statistically different).
  • Nirsevimab: Single-dose; given before/during RSV season.4-7
    • Versus placebo:
      • Premature, healthy: 1453 infants (born between 29-35 weeks).4 At 150 days:
        • RSV hospitalization: 0.8% versus 4.1% (placebo); RRR=81%; NNV=3.
        • Mortality (after one year) 0.2% versus 0.6% placebo, not statistically different (PEER calculation).
      • Term/near-term, healthy: 3012 infants.5,6 At 150 days:
        • RSV hospitalizations: 0.4% versus 2.0% (placebo): RRR=78%; NNV=63.
        • Deaths (after one year): 3 nirsevimab versus 0 placebo (none attributed to nirsevimab or RSV).
    • Versus no treatment (unblinded):
      • 8058 infants: 85% born ≥37 weeks.7 At three months:
        • RSV hospitalizations: 0.3% versus 1.5% (no treatment); RRR=82%, NNV=82.
        • One-year data forthcoming.
  • Adverse events: Similar between palivizumab, nirsevimab and placebo.1,4-8
  • Limitations: Many RCT authors were shareholders/employees of industry funder.4,5

  • In Canada, RSV responsible for ~2,500 childhood hospitalizations annually.9 Of those hospitalized:
    • ~80% had no underlying medical conditions, were <2 years old.10
    • Mortality: 2/1000.
  • In Canada, palivizumab recommended for high-risk infants:11
    • Prematurity (<30 weeks).
    • <2 years with chronic lung/congenital heart disease.
    • Living in remote/northern communities.
  • Nirsevimab:
    • Anticipated Canadian availability/guidance/pricing:12 2024
    • Versus palivizumab: Less costly (per patient).13
    • In US, recommended for all infants <8 months entering first RSV season.10
      • Second season: for high-risk infants (8-19 months).

Latest Tools for Practice
Derniers outils pour la pratique

#363 Making a difference in indifference? Medications for apathy in dementia

In patients with dementia, how safe and effective are stimulants, antidepressants, and antipsychotics for treating apathy?
Read Lire 0.25 credits available Crédits disponibles

#362 Facing the Evidence in Acne, Part I: Oral contraceptives and spironolactone in females

How effective are combined oral contraceptives (COC) and spironolactone for treating acne of at least mild-moderate severity in females?
Read Lire 0.25 credits available Crédits disponibles

#361 Preventing RSV Infections in Infants

How safe and effective are monoclonal antibodies to prevent respiratory syncytial virus (RSV) infections in infants?
Read Lire 0.25 credits available Crédits disponibles

This content is certified for MainPro+ Credits, log in to access

Ce contenu est certifié pour les crédits MainPro+, Ouvrir une session

  • Samantha S. Moe PharmD
  • Sam Wong MD FRCPC
  • Michael R Kolber MD CCFP MSc

1. Garegnani L, Styrmisdottir L, Rodriguez P. Cochrane Database Syst Rev. 2021; 11:CD013757.

2. The IMpact-RSV Study Group. Pediatrics. 1998; 102(3):531-7

3. Feltes TF, Cabalka AK, Meissner HC, et al. J Pediatr. 2003; 143: 532-40.

4. Griffin MP, Yuan Y, Takas T, et al. N Engl J Med. 2020; 383:415-25.

5. Hammitt LL, Dagan R, Yuan Y, et al. N Engl J Med. 2022; 386:837-46.

6. Muller WJ, Madhi SA, Nuñez BS, et al. N Eng J Med. 2023; 388;16: DOI:10.1056/NEJMc2214773.

7. Drysdale SB, Cathie C, Flamein F, et al. N Eng J Med. 2023; 389;2425-35.

8. Domachowske J, Madhi SA, Simoes EAF, et al. N Eng J Med. 2022; 386(9):892-4.

9. Bourdeau M, Vadlamudi NK, Bastien N, et al. JAMA network open. 2023; 6(10):e2336863.

10. Jones JM, Fleming-Dutra KE, Prill MM, et al. MMWR Morb Mortal Wkly Rep. 2023; 72:920-925.

11. Public Health Agency of Canada. National Advisory Committee on Immunization: Recommended use of palivizumab to reduce complications of respiratory syncytial virus infection in infants. 2022. Available at: Accessed December 13, 2023.

12. CADTH. Nirsevimab (Beyfortus) for respiratory syncytial virus prevention in neonates and infants. 2023. Available at: Accessed March 6, 2023.

13. CADTH. Cost-effectiveness of nirsevimab for prevention of respiratory syncytial virus outcomes in infants. 2023. Available at: Accessed March 6, 2023.

Authors have no conflicts to declare.