Cost-effectiveness of vaccinating adults aged 60 years and older against respiratory syncytial virus

Abstract

Respiratory syncytial virus (RSV) causes substantial morbidity and mortality in older adults. In May 2023, two subunit RSV vaccines (Arexvy [GSK] and Abrysvo [Pfizer]) received approval from the U.S. Food and Drug Administration (FDA). In June 2023, ACIP recommended that adults aged ≥60 years may receive a single dose of RSV vaccine, using shared clinical decision-making. In support of development of this policy, our objective was to assess the cost-effectiveness of RSV vaccination in the general population in this age group. We used a decision-analytical model of RSV over a two-year timeframe using data from published literature, FDA documents, epidemiological databases, and manufacturer data. We tracked RSV-associated outpatient, emergency department, inpatient healthcare utilization, RSV-attributable deaths, quality-adjusted life-years lost (QALYs), and societal costs. The societal cost per QALY saved from RSV vaccination depended on age group and product: adults aged ≥60 years, $196,842 for GSK's vaccine and $176,557 for Pfizer's vaccine; adults ≥65 years, $162,138 for GSK and $146,543 for Pfizer; adults 60- <65 years, $385,829 for GSK and $331,486 for Pfizer. Vaccine efficacy, incidence of RSV hospitalization, and vaccine cost had the greatest influence on cost per QALY. Cost per QALY saved decreased as the age of those vaccinated increased. Inputs such as long-term efficacy are uncertain. RSV vaccination in adults aged ≥60 years may be cost-effective, particularly in those of more advanced age. Lower vaccine acquisition costs and persistent efficacy beyond two RSV seasons would render RSV vaccination more cost-effective for a broader target population. PRIMARY FUNDING SOURCE: US Centers for Disease Control and Prevention.

Keywords: Adult RSV disease; Cost-effectiveness; Vaccination.

Fig. 1.

One-way sensitivity analyses, base incidence, 2-year timeframe, ICER ($/QALY). QALY: quality adjusted life year; ICER: Incremental cost-effectiveness ratio; VE: vaccine efficacy; ED: emergency department; S1: season 1; S2: season 2. Note: The ICER measures the cost per QALY saved with vaccination. The colored bars show how the incremental cost-effectiveness ratio can change as the input parameter assumptions change. Parameters are ranked by their influence on the base case ICER. The blue bars represent what happens to the ICER when the input parameter is low, and the orange bar represents what happens to the ICER when the parameter is high. Input ranges for parameters can be found in the input tables in Appendix Tables 1–8. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)

Fig. 2.

Scenario analyses with varying RSV incidence and vaccine cost, ICERs, ($/QALY), age ≥ 65 years, 2-year timeframe. Lower incidence corresponds to 95 % PCR sensitivity while higher incidence is based on the upper bound of the 95 % confidence limit.

Fig. 3.

Scenario analyses with varying vaccine efficacy duration and vaccine cost. The efficacy assumptions are slightly different for each product. We used 18 months for GSK and 14 for Pfizer because those are the available time points for efficacy data for each product. In the base case, we assumed efficacy fell to zero after those time points. In the “shorter” scenario, we assumed efficacy immediately dropped to zero (at 18 months for GSK, 14 months for Pfizer). In the “longer” scenario, we assumed efficacy dropped to zero by 36 months.