It's a question on many minds: When should we think about the next COVID-19 vaccine? Or should we?

At this point, no one knows for sure, but new guidance may be on the docket.

The issue is important, as there are still people dying from COVID-19. Yet, uptake of the newest vaccine, the bivalent booster, has been slow. There is only a small percentage of the population 5 years that has gotten it; for those most vulnerable to COVID19 – those 65 and up – the number is less that 40%.

COVID Vaccines, 2023 and Beyond

Meanwhile, infectious disease experts have widely differing views on what the vaccination landscape of 2023 and beyond should look like. Among the areas of disagreement are how effective the bivalent vaccine is, which people most need another shot, and what type of vaccine is best.

"I think we probably will need another booster," says Peter Hotez, MD, PhD, dean of the National School of Tropical Medicine at Baylor College of Medicine, and co-director of the Center for Vaccine Development at Texas Children's Hospital in Houston. "The question is, what is it going to be? Is it going to be the same bivalent that we just got, or will it be a new bivalent or even a trivalent?"

The trivalent booster, he suggested, might include something more protective against XBB.1.5. The bivalent booster gives "broadened immunity" that is improved from the original booster shots, says Eric Topol, MD, founder and director of the Scripps Research Translational Institute in La Jolla, CA, and editor-in-chief of Medscape, WebMD's sister site for health professionals.

While boosters can help some groups – such as older adults, people with multiple health conditions, and those with compromised immune systems – he opposes a recommendation that's population-wide.

Evolving Research

Among the key questions: How well can a vaccine work against a single subvariant, when no one can say for sure what the next predominant subvariant will be?

Much more research has become available recently about the bivalent vaccine and its effectiveness. "The bivalent vaccine is working as well as we could have expected," he says, especially in high-risk people and in those over age 65. The challenge we have is, what does that mean going forward?"

In his review, Topol concludes: "There is now more than ample, highly consistent evidence via lab studies and clinical outcomes to support the bivalent's benefit over the original booster." Among other evidence, he looked at eight studies, including four that used a live virus as part of the research. Six of the eight studies showed the bivalent booster is more effective against the BA.5 variant, compared to the original booster shots. Two others showed no real difference.

The US CDC needs to parse the data by subgroups, Offit says. "The critical question is, 'Who gets hospitalized and who is dying? Who are they?'" That data should take into account age, ethnicity, vaccine history, and other factors, Offit says, because right now, there is no great data to say, "OK, everyone gets a boost."

Future Vaccine Costs

Another debate – for not only current boosters but future ones, too – centers on cost. Without congressional action to fund more vaccines, vaccine makers have suggested their prices may reach $130 a dose, compared to the average $20-per-dose cost the federal government pays now, according to a Kaiser Family Foundation report.

"The huge increase in price that you have proposed will have a significantly negative impact on the budgets of Medicaid, Medicare and other government programs that will continue covering the vaccine without cost-sharing for patients." according to US Sen. Bernie Sanders (I-VT). He pointed out, too, the $19 billion in profits Moderna has made over the past 2 years.

While most people with health insurance would likely still get the vaccines and booster for free, according to the Kaiser analysis, a higher price will discourage people from keeping up with recommended vaccinations, including a possible new booster,

Are New, Variant-Specific Boosters Coming?

Are Moderna, Pfizer-BioNTech, and others developing more variant-specific vaccines, boosters, or other advances?

Novavax, approved in July 2022 as a primary series and in some cases as a booster, is "also developing an Omicron-containing bivalent vaccine at the direction of public health agencies," says spokesperson Alison Chartan.

Pfizer responded: "When and if we have something to share we will let you know."

Moderna did not respond.

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