Evolving research
“We are trying to understand how to stay one step ahead rather than several steps behind [the virus],“ says Michael Osterholm, PhD, director of the Center for Infectious Disease Research and Policy at the University of Minnesota.
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, Dr. Osterholm says. “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, Dr. 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 with the original booster shots. Two others showed no real difference.
“The four live virus studies offer consistent evidence of broadened immunity for the BA.5 vaccine that is improved over the original booster shots,” Dr. Topol wrote. The evidence also found the bivalent antibody response superior against XBB, he wrote.
Dr. Topol also cited CDC data that supports the benefits of the bivalent shot on hospitalization in older adults. During November, hospitalization of adults 65 and above was 2.5 times higher for those vaccinated who did not get the booster, compared to those who got the updated bivalent booster.
Boosters do matter, Dr. Offit says. “But not for all.” In a perspective published Jan. 11 in the New England Journal of Medicine – the same issue that published the two studies finding few differences between the original and bivalent – Dr. Offit wrote that boosting is best reserved for vulnerable groups.
Chasing the variants with a bivalent vaccine, he says, “has not panned out. There remains no evidence that a bivalent vaccine is any better than what we had. Please, show me the data that one is better than the other.”
Dr. Offit believes the goal should not be to prevent all symptomatic infections in healthy, young people by boosting them “with vaccines containing mRNA from strains that might disappear a few months later.”
The CDC needs to parse the data by subgroups, Dr. 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, Dr. 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 with the average $20-per-dose cost the federal government pays now, according to a Kaiser Family Foundation report.
The government has spent more than $30 billion on COVID-19 vaccines, including the bivalent, to provide them free of charge.
The suggested price increase infuriated many. On Jan. 10, Sen. Bernie Sanders (I-Vt.), incoming chair of the Senate Committee on Health, Education, Labor and Pensions, sent a letter to Moderna CEO Stéphane Bancel, urging him to reconsider and refrain from any price increase.
“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.”
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, will a higher price discourage people from keeping up with recommended vaccinations, including a possible new booster?
“I think so, yes,” Dr. Hotez says, noting that vaccine reluctance is high as it is, even with free vaccinations and easy access.
“The government is balking at paying for the boosters,” he says. “I think it’s very tone deaf from the pharmaceutical companies [to increase the price]. Given all the help they’ve gotten from the American people, I think they should not be gouging at this point.”
He noted that the federal government provided not just money to the companies for the vaccines, but a “glide path” through the FDA for the vaccine approvals.
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.
A version of this article first appeared on WebMD.com.