Expert Q&A: Exploring the cost-effectiveness of RSV vaccines in older adults

In the United States, respiratory syncytial virus (RSV) hospitalizes an estimated 60,000-160,000 older adults each year, with severity increasing with age and comorbidities. Vaccine development has been in progress for decades; however, it wasn’t until earlier this year that the FDA approved two vaccines for use in older adults. 

In late June, public health and medical experts on the CDC’s Advisory Committee on Immunization Practices (ACIP) convened to propose RSV vaccination recommendations for older adults. The committee voted in favor of RSV vaccination in adults 60 and older with consultation from their doctors, and their recommendation was accepted by the CDC director. The vaccines are expected to be available this fall. 

As part of the meeting, a University of Michigan team presented their economic model, which examined the potential cost-effectiveness of these vaccines.

David Hutton, Ph.D., gave the presentation; he’s a professor of Health Management and Policy and Global Public Health at the University of Michigan School of Public Health and co-leads the project with Lisa Prosser, Ph.D., M.S., the Marilyn Fisher Blanch Research Professor of Pediatrics at the University of Michigan Medical School. Prosser is also director of the Susan B. Meister Child Health Evaluation and Research Center (CHEAR), a professor of Health Management and Policy at Michigan Public Health, and both Prosser and Hutton are members of the University of Michigan Institute for Healthcare Policy and Innovation.

In this Q&A, Hutton discusses their work and the findings presented at the ACIP meeting.

What does RSV incidence look like in older adults?

RSV is a significant disease in both children and older adults, leading to about 60,000-160,000 hospitalizations and 6,000-10,000 deaths in older individuals. Like many health issues for adults, the risks of needing to have medical attention—whether that be an outpatient visit, emergency department, visit or hospitalization—increases with age. And, the risk of dying from RSV increases with age in the elderly.

Can you explain the economic model your team developed?

Pharmaceutical companies have long been working on RSV vaccines. We started this project in 2018 to examine the cost-effectiveness of a “hypothetical” RSV vaccine. Over time, the vaccines have become real products, so now we are evaluating the cost-effectiveness of these newly approved vaccines from GSK and Pfizer.

Our main objective was to estimate the net population health and economic impact of providing RSV vaccines for all individuals over the age of 65 in the United States. We also examined the impact on populations aged 60-64. In order to provide these estimates, we took several things into account, including:

• The costs of the vaccine balanced with cost savings from averted RSV disease  
• The negative health effects from vaccine adverse events against the health benefits of averted RSV disease

With that, we were able to examine both morbidity and mortality, as well as any trade-offs between the health and economic impact of the vaccination policies. For example, in this case, vaccination has a net increase in costs, but it also improves population health outcomes.

What information can we take from this analysis?

Our modeling estimates that if 20% of adults 65 and older in the US were to get vaccinated with one of these vaccines, over 220,000 outpatient visits, 26,000 emergency department visits, and 22,000 inpatient stays and 1,100 deaths related to RSV could be averted over a two-year timeframe (the length of time over which we think the vaccine might be effective).  But, that would involve spending between 2 and 2.7 billion dollars on vaccinations.

Our analysis suggests that the vaccines could potentially be cost-effective, but whether they are cost-effective depends on a variety of factors. Our best estimate is that vaccinating adults age 65 and above with the RSV vaccine would mean spending about $100,000 to $150,000 per year of life in perfect health (Quality-Adjusted Life Year).

I think a lot of US health economists might debate whether that is a good investment, given how else we can spend our health dollars. But, it’s arguable that these vaccines might be cost-effective. However, because we still are not entirely certain how much of a population burden there is of RSV—and because these are new vaccines with uncertain prices and uncertain effectiveness—there still is substantial uncertainty about the results.

If the vaccine costs were lower, or if the RSV burden is higher than we estimated, or if the vaccine efficacy is higher and longer-lasting, it’s possible that these vaccines might be more clearly cost-effective. If the converse is true (vaccines are more expensive, RSV burden is not as great, and vaccine efficacy worse), then population vaccination would not look as good.

How does your work inform the advisory committee's recommendations? 

The cost-effectiveness is not the only thing the ACIP committee examines, but it is a very important part of their deliberations before voting on and providing recommendations. In my observations, they seemed very concerned about safety signals, long-term efficacy, and cost-effectiveness. During the meeting, several committee members mentioned that vaccine cost was a very important issue that was affecting their decision.

Separately, ACIP is beginning discussions on RSV interventions for infants. Your team is also working on economic models for this population. Can you briefly describe what’s happening on that front?

RSV is also a big burden for infants, with millions of outpatient visits and tens of thousands of hospitalizations each year. There are two new interventions for newborns. One is a monoclonal antibody given as an injection to the infant to reduce the risk of RSV infection. The other is a maternal vaccine that is designed to transfer antibodies to the newborn to reduce RSV infections in the infant. Both of these products are anticipated to provide protection to the infants for less than a year, but that is a critical time of high risk for those infants. With that said, these products are expensive and they do not provide 100% protection. 

Our analysis suggests that providing the monoclonal antibody would cost about $157,000 Quality-Adjusted Life Year (QALY) and providing the vaccine might cost $214,000 per QALY gained. These results are also sensitive to similar assumptions about RSV incidence, product efficacy, and product cost.