OBJECTIVES: RSV is common among young children in Canada. Although respiratory syncytial virus (RSV) often causes mild upper RTD (URTD), progression to lower RTD (LRTD) is associated with significant morbidity, mortality and high costs among young infants, those born prematurely and those with certain risk conditions. RSVpreF, Pfizer’s novel RSV vaccine, was recently approved by Health Canada to prevent LTRD in infants via active immunization of pregnant individuals. We evaluated the cost-effectiveness of maternal RSVpreF for prevention of RSV among infants in Canada aged <1 year.

METHODS: Clinical outcomes and economic costs of RSV during infancy and expected impact of year-round RSVpreF vaccination during pregnancy (vs. no intervention) were projected for 1 annual birth cohort using a population-based cohort model. Model parameter values (i.e., population characteristics, disease/fatality rates, costs) were estimated using data from published sources, as available, and unpublished sources, as needed. RSVpreF was assumed to provide protection against LRTD in any care setting and URTD treated in ambulatory settings; effectiveness was based on efficacy data from Pfizer’s Phase III clinical trial (“MATISSE”). Analyses were conducted from societal perspective with costs and quality-adjusted life years (QALYs) discounted at 1.5% annually.

RESULTS: With no intervention, there were 5,994 RSV hospitalizations, 24,233 RSV cases requiring emergency department (ED) care, and 84,618 RSV cases requiring a physician office (PO) visit; corresponding total economic costs were $173.0 million. With RSVpreF administered to 243,314 pregnant individuals, 229,280 infants had protection against RSV from birth, which prevented 1,943 hospitalizations, 3,740 cases requiring ED care, and 10,955 cases requiring a PO visit. With 338 QALYs gained and costs higher by $16.5 million, cost-effectiveness for RSVpreF (vs. no intervention) was $48,881/QALY.

CONCLUSIONS: An RSV immunization program including RSVpreF among pregnant individuals would substantially reduce the clinical and economic burden of RSV among infants in Canada and would be considered cost-effective.