Helen Branswell , 2025-04-30 08:30:00
It’s been less than three months since Robert F. Kennedy Jr. was sworn in as the U.S. health secretary and already there have been many signs the longtime critic of vaccines intends to use his extensive powers over regulation, policy, and research funding to influence Americans’ thinking about them.
There may be more indicators to come.
Over the next couple of months, Kennedy will have numerous additional opportunities to pursue his decades-long campaign against vaccines — often based on scientifically disproven allegations — should he choose to do so. Some are modest; others could be seismic — existential, even, for certain vaccine manufacturers.
There could also be opportunities to read the tea leaves to assess whether anyone in the White House or elsewhere in the administration is working to blunt Kennedy’s efforts, which vaccines advocates say would be highly damaging to public confidence in immunizations and thus to Americans’ health more broadly.
Here’s a look at eight questions that could indicate whether — and how aggressively — Kennedy might exert his influence in the coming weeks.
What the heck is happening with the Novavax Covid shot approval?
The Food and Drug Administration was supposed to announce a decision by April 1 on Novavax’s application for a full license for its Covid-19 vaccine, which has been deployed under an emergency use authorization since 2022. FDA insiders have revealed the professional staff recommended approval. But political appointees serving under new Commissioner Marty Makary paused the decision, a highly unusual move. Since then, there’s been a back and forth between the agency and the company — some in public, some in private — about an additional study Makary and political staffers want to see conducted.
The study is being cast as a “post-marketing commitment,” which would suggest the FDA will give Novavax the license it is seeking. But it has been reported — and Makary has seemed to confirm it — that the FDA wants a new randomized controlled trial to determine the effectiveness of the vaccine, which targets a more up-to-date version of the SARS-CoV-2 virus than the one used during the clinical trial the company conducted in 2021. (All Covid manufacturers update their vaccines annually; the FDA instructs them to do so.)
A new trial of this type would be costly and almost impossible to do. What would the control group in the trial receive? It would be unethical to use a placebo, or to vaccinate some with an earlier version of Covid vaccines to show how well the updated version works.
The Novavax vaccine is the only Covid shot on the U.S. market that isn’t made using messenger RNA — a vaccine platform distrusted by people in Kennedy’s Make America Healthy Again movement. One might have expected an FDA that answers to Kennedy would have been more open to the Novavax shot for that reason. But it appears not.
We’re watching this space closely.
Is the FDA proposing to overhaul the system for updating Covid shots?
For seasonal vaccines that require regular tweaks because the viruses they target keep changing, the FDA has developed a practical approach, known as the strain change rule. The viruses that flu and Covid vaccines target are updated annually, but the way the vaccines are produced remains the same. As a result, they are not treated like new vaccines and don’t need to undergo the lengthy and expensive studies required to first bring a vaccine to market.
Over the weekend, Makary appeared to suggest this approach may no longer be the norm for Covid vaccines, though additional information from an official at the Department of Health and Human Services implied flu vaccines would continue to be handled through the strain change rule.
Was Makary only trying to find a way to defend the decision to throw up more hurdles for the Novavax approval? Or is his agency thinking about changing the number of hoops all Covid vaccine manufacturers have to clear to bring updated vaccines to the U.S. market? Is it considering scrapping approvals for updated Covid shots altogether, an option Makary appeared to suggest was on the table during a CBS interview Tuesday?
If the FDA is going to ask Moderna and Pfizer for new trials too, it might be asking the impossible. Studying how protective an updated Covid shot is can only be done during a surge in cases. By the time the data were generated and analyzed, the surge would be over and the need and demand for the vaccine would have passed.
As Michael Osterholm, director of the University of Minnesota’s Center for Infectious Disease Research and Policy, put it, “by the time they could get vaccine approved with early season studies, it would be too late … to get vaccine out. It makes no sense at all.”
What is going to happen to Moderna’s next-generation Covid vaccine?
While Novavax awaits an FDA decision on its vaccines, Moderna has its own big verdict from the agency pending — on its next-generation Covid shot. The FDA has told Moderna it will render a decision by May 31. Will it meet this deadline? Will it approve this vaccine?
The shot, known for now as mRNA-1283, contains one-fifth of the antigen used in Moderna’s existing Covid shot, Spikevax, and targets only parts of the virus’ spike protein, not the entire protein. In testing, the antibodies the new version generated lasted longer than those triggered by Spikevax, and the vaccine was shown to be at least as effective as the currently marketed product. When trying to bring a new version of a vaccine to market, a manufacturer must show it is “noninferior” to an existing product.
Moderna would like to supply the new version of the vaccine to the U.S. for the fall. “We continue to work closely with the FDA and teams across HHS to ensure our products are available to protect Americans,” a spokesperson for the company told STAT.
But as mentioned above, there seem to be concerns about both Covid vaccines and mRNA vaccines among the political appointees at the highest echelons of the FDA and HHS. Kennedy has repeatedly questioned the safety of mRNA vaccines; in an interview recorded before his confirmation as director of the National Institutes of Health, which was circulating last week on social media, Jay Bhattacharya also questioned the safety of these vaccines.
Tracy Beth Høeg, a special assistant to Makary, posed a question at a meeting of the Advisory Committee on Immunization Practices earlier this month that suggested she may have some doubts about the Moderna Covid vaccine. (The ACIP is an expert panel that advises the Centers for Disease Control and Prevention on vaccine use.)
Her comment wasn’t about the new vaccine, but rather the vaccine it had been compared to. How could Moderna even know at this point whether Spikevax still works, Høeg asked, given how much underlying immunity people now have to SARS-2 viruses? Darin Edwards, team lead for Moderna’s Covid vaccines program, explained that the company conducts vaccine effectiveness studies during the Covid season to see how the strain in the vaccine protected against the circulating viruses.
Meanwhile, there appears to be an organized effort in some quarters to block all use of mRNA vaccines, with lawmakers in several states launching as-yet unsuccessful efforts. Most recently, draft legislation dubbed the “mRNA Bioweapons Prohibition Act” was introduced in Minnesota’s House of Representatives. In Minnesota’s current political configuration it will not advance. But the proposed bill’s wording is interesting and frankly alarming, experts say. It would designate mRNA vaccines and other products containing mRNA as “weapons of mass destruction.”
“Is anybody at the federal government level going to respond to activities like that?” Osterholm asked at a press conference last week where he announced the launch of an effort to fend off threats to vaccine policy called the Vaccine Integrity Project.
What is the future of Covid vaccines for children?
Politico reported last week that Kennedy is considering removing Covid shots from the pediatric vaccine schedule, the detailed list of which vaccines children should get and at what age compiled by the CDC, with help from the ACIP.
It would be unprecedented for an HHS secretary to unilaterally strike a vaccine from the childhood vaccine schedule, especially if he were to do so without holding hearings to explain the rationale and in the absence of compelling data supporting such a decision.
(Ironically, the ACIP may vote in June to change its Covid vaccine recommendation, a change that might get part way to Kennedy’s goal here. A subcommittee studying the issue supports a plan to replace the current “universal” recommendation for Covid — everyone 6 months and older should get it — with a more targeted one based on who is most at risk from the virus. Very young children might be in that at-risk group, but healthy school-aged kids and teens would not.)
Removing the pediatric Covid vaccines from the schedule would not mean they would be banned from the market. But as with many of the vaccine-related moves Kennedy makes, it would increase confusion and potentially fuel a sense among parents that their kids don’t need or shouldn’t get these shots. It would make it more challenging for pediatricians to figure out who to vaccinate and when.
It could also mean parents who wanted to get their kids vaccinated against Covid might have to pay some or all of the cost, which would definitely depress uptake. Use of the vaccines in children has always been low; only 13% of children under the age of 18 were vaccinated against Covid for the 2024-2025 season.
It would likely drop further if insurers stopped paying for the vaccines in full — which they could — or if Kennedy also struck the vaccines from the list of those that qualify for coverage under the Vaccines for Children Program. The VFC is a congressionally created program that picks up the tab for kids whose parents cannot afford the cost of vaccines. Just over half of American children get their vaccinations through VFC.
This discussion comes at a time when the FDA will soon need to make a decision on whether to give full licenses to both the Pfizer-BioNTech and the Moderna vaccines for children, both of which are still used under emergency use authorizations.
How and when will the strain for next season’s Covid shot be selected?
Covid shot manufacturers that supply the U.S. market will need to know soon what version of the SARS-2 virus the shots for the fall should target. The makers of the messenger RNA vaccines, Moderna and Pfizer, still have a little wiggle room, but for Novavax, time is of the essence. The vaccine platform the company uses takes longer to produce than the mRNA shots do.
Last year the FDA’s decision, which came in mid-June, was too late for Novavax, which had already started to make doses based on the strain it thought the agency would recommend. The FDA changed course at the last minute, though it allowed Novavax to bring its version of the shots to market.
In the first week in May, experts advising the World Health Organization will recommend which strains they believe the shots for the 2025-2026 Northern Hemisphere winter should aim to protect against. But it is not clear what, if any, involvement U.S. health agencies will have in that process, given the Trump administration’s announced withdrawal from the WHO. Even if that weren’t happening, the FDA hasn’t always parroted the WHO choice; last year its advice to manufacturers differed from what the WHO had recommended.
The FDA’s expert vaccines panel, the Vaccines and Related Biological Products Advisory Committee, hasn’t met since Kennedy took over HHS. A meeting of the group that would normally have been held in early March to advise on the composition of flu shots for next winter was canceled. Will VRBPAC be convened to advise on the Covid shot question? STAT is hearing rumblings that it will, but given those meetings require a period of public notice, if it’s to happen, the FDA needs to announce it soon.
The lack of clarity around the process is challenging for manufacturers, acknowledged an official at one of the companies, who asked not to be identified.
STAT has asked HHS’ communications office whether a VRBPAC meeting will be called. “More information will be available soon,” press secretary Emily Hilliard replied via email.
Will HHS accept recent vaccine recommendations from the CDC’s advisory panel?
After a two-month delay, the ACIP — the expert panel that advises the CDC on vaccines — met in mid-April. ACIP voted to recommend use of two new vaccines — for meningococcal disease and chikungunya virus — and to alter guidance on who should get another chikungunya vaccine and vaccines to protect against respiratory syncytial virus.
For the ACIP’s recommendations to become policy, they must be accepted by the CDC director. But there is no CDC director at present, and no acting director, since Susan Monarez, who served in that position, was named the administration’s nominee for the post. Monarez has not yet been through her confirmation process, and no date for a Senate hearing has been announced.
Lawyers who have studied the law buttressing ACIP suggest that, as HHS secretary, Kennedy could accept the recommendations in place of CDC director. But to date, he has not. It’s exceedingly rare for an ACIP recommendation to be overridden, and it’s not clear why Kennedy hasn’t accepted them. If he is reluctant to sign off on recommendations urging the use of these vaccines, the new guidance could languish until the Senate confirms a CDC director.
STAT has asked HHS’ communications department if and when Kennedy plans to sign off on the ACIP recommendations.
What about Moderna’s bid to expand who is eligible for its RSV vaccine?
Around mid-June, the FDA faces another deadline for a different Moderna product. The company has asked the regulatory agency to expand the license for its RSV vaccine, mResvia, to allow its use in adults ages 18 to 59 who have underlying medical conditions that put them at increased risk of severe illness from RSV. The vaccine, made using Moderna’s mRNA platform, was licensed last spring for adults 60 and older.
The FDA has already approved two other RSV vaccines, made by GSK and Pfizer, for use in younger adults who are at high risk from the virus. At its mid-April meeting, the ACIP voted to recommend expanding the pool of people eligible for RSV vaccination to include high-risk individuals ages 50 to 59. If the FDA agrees to broaden Moderna’s license — and if the CDC director or HHS secretary accepts ACIP’s recommendations — that expansion should apply to the Moderna vaccine as well as the GSK and Pfizer products.
Will FDA meet its deadline? Are the concerns among the political staff in Makary’s office limited to Covid vaccines, or mRNA vaccines writ large? This decision may give us some clues.
What’s going to happen to Moderna’s BARDA contract?
The Biomedical Advanced Research and Development Authority is a division of HHS tasked with spurring development of drugs, vaccines, tests, and other tools the country would need to respond to a biological or bioterrorism event. It incentivizes industry to work on medical countermeasures for which there is no current market — products like vaccines to protect people against dangerous bird flu viruses that might one day trigger a pandemic.
BARDA has helped several vaccine manufacturers produce, test, and license H5N1 bird flu vaccines. Some doses of these vaccines are stockpiled. But the main goal here is to have a manufacturer license a vaccine for that strain of flu so that if an H5N1 pandemic were to occur, the FDA could use the strain change rule described earlier to fast-track production and deployment of the vaccine.
In the final months of the Biden administration, BARDA entered into one such contract with Moderna, to have it generate vaccines for H5N1 but also three other flu viruses that scientists believe could potentially cause a pandemic one day. The contract is worth nearly $600 million.
For context, Operation Warp Speed, which fast-tracked and delivered several Covid vaccines, cost $18 billion.
The three H5N1 vaccines that have already been licensed are made with traditional production methods that are slow. Even with the advance testing and licensing, those vaccines would take at least six months to start to roll off the production line.
But mRNA vaccines can be made rapidly, and production can be scaled up quite easily. It explains why some experts reacted with deep alarm to a Bloomberg story in late February that revealed the Trump administration was weighing pulling funding from the project.
Though HHS confirmed that the contract was being reevaluated, it gave no rationale for the move. And there has been nothing else said publicly about this project in the intervening two months.
Will it survive? Will it be trimmed? Everyone concerned about pandemic planning is watching this one.
It’s worth noting that not every action the Trump administration takes fits into a clear pattern. On the one hand, it might seem that any vaccines related to mRNA technology might be on the chopping block; on the other, earlier this month the FDA awarded a fast-track designation to a self-amplifying mRNA vaccine against H5N1 being developed by Arcturus Therapeutics.
That work is being funded by BARDA.
