Vaccine development

Demetre Daskalakis joined the Centers for Disease Control and Prevention in 2020. Along the way, he helped lead a response to the mpox outbreak and, more recently, ran an agency division focused on containing infectious diseases like influenza and COVID-19. 

From that vantage point, Daskalakis saw, firsthand, an unsettling shift in the way the CDC operated once Robert F. Kennedy Jr. took control of the Department of Health and Human Services and the web of agencies under its purview. Daskalakis says he had an open mind when Kennedy, a known vaccine skeptic, came aboard. He was prepared to aid Kennedy’s desire to better public health and show him the ins and outs of the CDC. But what he saw instead was a raft of policies he believes prioritize ideology over established science. 

Daskalakis calls the series of changes “death by 1,000 cuts.” Each slash, from unorthodox tweaks to vaccine policy to the sudden removal of respected agency director Susan Monarez, tarnished the CDC’s standing with the scientific community and eroded public trust. Last summer, he published a scathing letter as he and two other senior CDC officials resigned in protest. 

“It became pretty clear that with the loss of any scientific leadership at CDC, there was not going to be a way forward that wouldn't compromise my ethics and my ‘first, do no harm’ Hippocratic oath,” he said. 

Daskalakis, now an outspoken critic of the agency and its actions, likens the CDC to a “hijacked plane.”

“You have this very important agency that is being steered by people that don't have the goal of public health really as their main mission,” he said.

A sudden transformation

The CDC’s main objective is to protect the American public from disease threats. It monitors emerging outbreaks, coordinates a response, and helps guide the public, physicians and state agencies on vaccinations as well as other preventive measures.  

Like other federal health organizations, the CDC became a political target in the wake of the COVID-19 pandemic amid anger over lockdown and vaccination policies. Its weaker standing was seized on by President Donald Trump, who nominated Kennedy to lead HHS and “restore” the CDC and other public agencies to “the traditions of gold standard scientific research.”

The choice was controversial. Kennedy founded and chaired the Children’s Health Defense, a prolific anti-vaccine group that’s spread false claims about the safety and effectiveness of childhood inoculations. He’d also long publicly crusaded against the adoption of approved vaccines, citing debunked links to autism and chronic health conditions.   

Ahead of his confirmation, Kennedy vowed to “clean up corruption” at the nation’s public health agencies. In the CDC’s case, that’s resulted in major staffing cuts, leadership turnover and dramatic shifts in the way the agency forms new recommendations.  

The most impactful of those moves has been the reorganization of the Advisory Committee on Immunization Practices, or ACIP, a crucial panel that issues vaccine guidance linked to insurance coverage. The committee is comprised of independent experts with backgrounds in infectious disease or public health and that are vetted through a rigorous process. That panel then carefully reviews evidence gathered by smaller “working groups” and pharmaceutical representatives before recommending who should, or shouldn’t, receive new immunizations. 

Last June, Kennedy abruptly fired all 17 members of that panel and hastily replaced them with a smaller group largely aligned with his views or without relevant expertise. Scientists and public health veterans widely criticized the secretive way the new group was selected, and expressed concern that the reformed ACIP’s mandate was to enact an already agreed-on agenda. 

“We don't really know what was going on behind the scenes as far as picking the replacements, because there's not been much transparency,” said Kevin Ault, vice president of the National Foundation for Infectious Diseases, who previously served on ACIP and was a former liaison for the American College of Obstetricians and Gynecologists, or ACOG.

Jeffery Goad, the NFID’s president and former liaison to one of the CDC’s work groups, called the move a “radical departure” from what was observed during previous presidential administrations. 

“The CDC and ACIP have been in place and independent through every political change. It doesn't matter what party is in power. The scientific process, the rigor, the independence of the CDC and ACIP has always been there,” he said. 

Meanwhile, the agency altered website language regarding vaccine safety. Many surveillance databases, chiefly involving vaccination topics, stopped being updated. And Monarez was fired less than a month into her tenure for refusing to rubber-stamp new vaccine guidelines without supportive evidence. Her departure spurred the resignations of several senior leaders, including Daskalakis, and led to widespread calls for Kennedy to step down. 

“Each one of the events really led the people at the CDC, especially in my center, to feel more and more like they are unable to effect any change,” said Daskalakis. Monarez was “interested in doing the right thing” and “really wanted to bring order and reason to what was happening at ACIP,” he added.

HHS spokesperson Andrew Nixon said in an email to BioPharmaDive HHS continues to rely on input from scientists and experts across the agency.

Upending vaccine policy

In less than a year, Kennedy’s reformed ACIP committee has directed a series of changes that have gone against longstanding scientific evidence in weakening support for several routine inoculations. 

The panel dialed back support of a birth dose protecting newborns against hepatitis B infections that can cause deadly complications later in life. The panel has also questioned the evidence supporting COVID-19 vaccines as well as routine childhood immunizations, voted to split measles and varicella shots and indicated plans to dig into an immune-boosting adjuvant used in several vaccines. 

The committee’s focus seems to be “what can we do to reduce vaccination, rather than what can we do to protect the public,” claimed Robert Hopkins, medical director of the NFID and a liaison to ACIP. The meetings, he thinks, are “political theater.”

“ACIP is doing what it’s supposed to do, evaluate the evidence and have an open debate, not rubber-stamp prior consensus,” Nixon said. 

The process by which these changes were made has raised alarm from career scientists. Some ACIP presentations, for instance, came from unorthodox sources with a history of vaccine skepticism. 

Liaisons to major medical organizations have also been barred from participating in work groups. These liaisons provided critical assistance in collecting, analyzing and presenting evidence on the topics ACIP reviews, as well as the language of the issues the panel ultimately votes on. 

Experts worry the sidelining of liaisons means CDC subject matter experts are unable to provide data to ACIP, and signals the committee no longer follows established frameworks for decision-making. 

“Since the ACIP has been reconstituted last year, nothing that has been put forward by them is based on science or evidence, not one single change. This is unlike the previous 50-year history,” said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota. 

“Right now, the changes that are occurring are by dictum, without any data or information to support their change,” he added. 

Ault, meanwhile, noted that while liaisons can participate in public meetings to provide insight to ACIP members, they’re often ignored. 

“[Members] had their hands raised, and nobody would call on them. And I don't know if that's just part of the general disorganization of the group, or if that was purposeful, but either way, it doesn't look good,” he said. 

When asked if participants have been ignored and if factual data has been sidelined, Nixon said those claims are “completely false.”

“CDC experts and liaison members have attended the ACIP meetings. Additionally, multiple liaison groups, including AAP, have refused to participate,” he added. 

The CDC also bypassed ACIP in January by announcing it would reduce the number of universally recommended childhood shots to 11, down from the previous 17. The agency claimed the decision was made to align the U.S. schedule with certain other wealthy nations. But that argument was challenged by scientific experts, who noted the call was made without public debate of data supporting such a drastic policy shift. 

“It's a very dark time for evidence-based recommendations coming from CDC,” Hopkins said. 

Growing distrust

The CDC’s transformation has disrupted the way the U.S. issues health guidance to the public.

Already, multiple medical groups, including ACOG, the Infectious Diseases Society of America and the American Academy of Pediatrics have put forward their own vaccination recommendations. Several states have rejected official CDC vaccine guidance, too. And other initiatives, like the nonprofit Vaccine Integrity Project, have emerged to, as its executive director Osterholm says, “do the work” ACIP and its work groups had been known for. 

“I think there's a pretty universal acceptance out here that the ACIP’s recommendations are seriously flawed and not based on good science,” he said. “So I think you're going to continue to see the medical community supporting this alternative approach.”  

Nixon refuted this, saying, “At each meeting, the ACIP committee conducts a thorough review of the scientific evidence presented by experts and engages in open, substantive debate before voting.”

A lawsuit brought on by several medical organizations also resulted in a federal court recently blocking the changes the CDC made to the vaccine schedule. That decision also halted all of ACIP’s decisions and left unclear the next time the group will meet. Some published reports, as well as a post from a member, have indicated the current group may be disbanded. One member has already stepped down.

When asked if ACIP is or will be disbanded in the future, Nixon said, unless it is officially announced by HHS, “any assertions about what [HHS is] doing next is baseless speculation.”

The court decision represented a victory in the eyes of medical experts. But there are tough challenges ahead. For one, conflicting messages between the scientific community and federal government could deepen confusion among the American public and strain local and state health departments. 

“That's going to continue to be an issue as the CDC continues to depart from evidence-based recommendations, and as that divide widens, it's going to become even more difficult for payers, for the public and healthcare providers to reconcile these differences,” Goad said.

Medical groups are also struggling to consistently refute government-endorsed recommendations that fly in the face of established science. 

“I think the hardest part has been trying to educate or make the public aware of how far from procedure and evidence-based decision-making we've gone,” said Annicka Evans, a bioengineer and contractor for the Evidence Collective, a group of scientists and health communicators aiming to provide rapid, factual responses on public health issues. 

Experts worry that lasting damage may have already been done. Recent polling from the independent media organization KFF showed that trust in the CDC is at its lowest point since the beginning of the COVID pandemic. A steady decline in vaccination rates has coincided with more severe flu seasons as well as a flurry of measles outbreaks that have threatened the disease’s elimination status in the U.S.  

“I think what scares me is being able to make sure that we can bring people back to trusting in [HHS leadership] when the time is right,” Evans said.

Nixon, however, said the decline in trust started “long before the Trump Administration.”

“Secretary Kennedy’s mandate is to restore transparency, scientific rigor, and accountability so trust can be earned back. We’re restoring rigor, transparency, and accountability to public health decision-making, and that’s exactly how you rebuild trust,” he added. 

Ault worries, though, that the damage may have already been done regarding the spread of preventable diseases. He warned, “Unfortunately, I think the worst is yet to come."

To many scientists and doctors, messenger RNA vaccines are an incredible feat of modern medicine. But to top health leaders in the Trump administration, shots made with the technology pose more risks than they do benefits.

Last August, Secretary Robert F. Kennedy Jr. directed the Department of Health and Human Services to cancel some $500 million in contracts for research and development of mRNA vaccines, which are credited with helping control the COVID-19 pandemic.

The controversial move is a U-turn from the first Trump Administration, which created “Operation Warp Speed” to develop, manufacture and distribute COVID vaccines in record time, and in the process gave mRNA technology a starring role.

“To go from the identification of a pathogen to the development of an efficacious vaccine within the period of nine months — never happened in human history, and it was only made possible because of mRNA,” said Jeff Coller, a professor of RNA biology and therapeutics at Johns Hopkins University.

“It's absolutely perplexing as to why President Trump would allow Robert Kennedy to undermine his legacy in creating these life-saving therapeutics that literally saved millions of lives,” Coller added.

Scientists worry Kennedy’s actions, which have followed other major changes in U.S. vaccine policy, might leave American medicine lagging behind China and other countries that once sought access to the same technology. Moreover, mRNA has shown promise as a drugmaking platform in other fields besides infectious disease, most notably in cancer.

Moving away from mRNA vaccines to embrace older technologies could delay the U.S. government’s response in future pandemics, too.

“If we go back and use the technologies [Kennedy] is proposing should be used for vaccinations, we would be five, six years into a pandemic with millions of lives lost before we even had a vaccine that might be able to work,” said Coller. “So this is a critical national security issue.”

Long a prominent critic of vaccines, Kennedy has questioned mRNA shots since the early days of the pandemic. In ordering the cancellation of HHS contracts, he claimed mRNA vaccines “fail to protect effectively against upper respiratory infections like COVID and flu,” despite the success of the COVID vaccines developed by Moderna and partners Pfizer and BioNTech. Their safety and efficacy was initially proven in large, placebo-controlled studies, and then by the experience of the tens of millions of people who received them around the world.

While they are associated with some side effects, including, in rare instances, potentially concerning heart inflammation, most people have mild or no adverse reactions. COVID can cause heart inflammation as well.

“The goal of this vaccine is to keep you out of the hospital, keep you out of the intensive care unit, and keep you out of the morgue,” said Paul Offit, a vaccine expert and professor of pediatrics at the Children’s Hospital of Philadelphia. “That's the goal. [Kennedy] doesn't understand that, or he does understand that and he's just saying what he says to scare people.”

HHS provided a list of data it says demonstrates the harms caused by mRNA vaccines. The studies appear cherry-picked to support that conclusion, however, and were compiled by individuals who have criticized the U.S.’s pandemic response.

National Institutes of Health Director Jay Bhattacharya, who in October 2020 co-wrote a proposal to end COVID isolation policies, claimed the administration defunded mRNA research because of public distrust of the technology. The NIH has also deprioritized some COVID research.

“COVID-19 is probably the most politically charged disease of the last 50 years or more, and there are people who have very strong feelings about how the disease was treated, epidemiologically, at the societal level, that has almost nothing to do with the potential of mRNA,” said Jonathan Kagan, co-founder of mRNA drug developer Corner Therapeutics and professor at Harvard Medical School.

“It just happens to be that the only FDA-approved drugs on the market today that use mRNA are COVID-19 drugs,” Kagan added.

Messenger RNA, a nucleic acid that cells use to translate genetic code into proteins, provides an easily adaptable foundation for medicines. That flexibility means scientists can respond more quickly in response to viral outbreaks, such as with avian influenza, than they can with traditional types of vaccines, which typically take longer to design and produce. It has aided Moderna and Pfizer in updating their COVID boosters yearly.

“Bird flu may never become a pandemic, but if it does, this kind of technology allows you to respond much more quickly than a traditional technology like whole-killed viral vaccine,” said Offit.

Kagan, of Corner Therapeutics, sees investment in mRNA as essential to U.S. science leadership, similar to how the federal government’s support of research in nuclear energy and physics helped the U.S. win the Cold War.

“It appears that our federal government does not realize that we're in the middle of another arms race — it's an arms race for biomedicine,” Kagan added.

Recent studies have shown mRNA medicines’ promise against several cancers, including those of the pancreas, colon and brain. Targeting cancer is now a focus for Moderna, as sales of its COVID vaccine have evaporated and the Food and Drug Administration has narrowed COVID vaccine approvals.

Moderna was one of the companies affected by HHS’ contract cancellations. The company did not respond when reached out to by BioPharma Dive.

Others affected by HHS’ cuts, including Sanofi, CSL Seqirus, Gritstone Bio and Emory University, did not reply to BioPharma Dive’s request for comment.

While a leading mRNA drug developer, BioNTech was not affected. In an emailed statement, the company said it continues to “believe in the potential of mRNA in medicine” in both infectious disease and in cancer.

Kagan believes positive data for mRNA cancer treatment could eventually sway the administration’s attitude toward the technology, but warned that its current policies will weigh on the field.

“When you cut back investment in this area, there's less chance for tangible innovation,” Kagan said.

Otello Stampacchia, managing director at life sciences investment firm Omega Funds, said that, while the firm doesn’t typically back vaccine developers, HHS’ messaging does affect investment broadly.

“It's super hard for a firm like ours to touch those things when there's such a clear political blowback," Stampacchia said.

Coller, who is also on the board of the Alliance for mRNA Medicines, noted that in a survey conducted by the group earlier in the year, about half of respondents indicated their mRNA-developing companies had already experienced negative consequences from federal policy changes.

“These actions are scaring manufacturing and biotech away from the United States,” Coller added. “I think [the HHS announcement] was a shot across the bow to the industry that you're not welcome here anymore,” Coller added.

Coller and Kagan both agreed HHS’ actions give an opening to other countries like China to make up ground in mRNA drug development.

“China is accelerating, while the United States is killing the investments that they've already made and stifling new ones,” Kagan said. “That differential, sadly, is going to increase if we stay on this path.”

“The future is very bright for mRNA research in other countries,” Coller said.

Gwendolyn Wu contributed reporting.

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A federal judge in March temporarily blocked several major moves Health and Human Services Secretary Robert F. Kennedy Jr. has made to upend vaccine policy in the U.S., arguing the changes he and his agency directed likely violated federal law.

The 45-page ruling was issued in response to a lawsuit filed by six medical organizations, including the American Academy of Pediatrics, in July. In it, Brian Murphy, a district court judge in Massachusetts, stalled changes federal health officials made to the childhood immunization schedule in January. Murphy also temporarily halted all the decisions a key vaccine panel has made since Kennedy reformed the committee last year.

That panel, ACIP, didn’t meet in March as previously planned.

“[T]here is a method to how these decisions historically have been made — a method scientific in nature and codified into law through procedural requirements,” Murphy wrote. “Unfortunately, the government has disregarded those methods and thereby undermined the integrity of its actions.”

“HHS looks forward to this judge’s decision being overturned just like his other attempts to keep the Trump administration from governing,” HHS spokesman Andrew Nixon wrote in an email to BioPharma Dive.

Over the last year, Kennedy, a prominent vaccine skeptic, has made a series of decisions that have weakened the U.S.’ stance on vaccines for a number of childhood diseases and respiratory infections. Many of those moves came after he fired all 17 members of ACIP and reconstituted the panel with people more aligned with his views, including some without relevant backgrounds.

The new members have rolled back endorsements for multiple common immunizations, among them a dose protecting newborns against hepatitis B infections. They’ve gone against established scientific evidence supporting COVID-19 shots and other immunizations, and indicated plans to closely examine an immune-boosting adjuvant long used in a dozen standard childhood vaccinations.

ACIP members are typically vetted through a rigorous process. In his ruling, Murphy argued the government circumvented that protocol, raising a “substantial likelihood that the newly appointed ACIP fails to comport with governing law.” Murphy added that ACIP’s mandate is to evaluate vaccines and its new members “appear distinctly unqualified” for the task, supporting the plaintiffs’ charge that the panel’s reformation was “arbitrary and capricious.”

Murphy also found likely unlawful the CDC’s abrupt decision in January to narrow the number of universally recommended shots for U.S. children to 11 from the previous 17. The federal government bypassed ACIP in announcing those changes, a “technical, procedural failure” and an indicator of the “abandonment of the technical knowledge and expertise embodied by that committee.”

The AAP and other medical organizations sued HHS last July, after the federal government said COVID vaccines would no longer be recommended for pregnant women or healthy children. In January, the plaintiffs asked the court to halt changes to the vaccine schedule and prevent ACIP from meeting in February. ACIP was set to convene this week after that planned meeting was postponed. The judge’s order leaves unclear when the next gathering will take place.

“The judge recognized that the actions of Secretary Kennedy and [ACIP] are not grounded in science and that they are destructive. We are thrilled that the court has discarded the baseless vaccine schedule changes made by Secretary Kennedy and is blocking [ACIP] from doing further damage to vaccine policy," said Richard Hughes, a partner at the law firm Epstein Becker Green and an attorney for the plaintiffs, in a statement.

A key vaccine panel in December weakened recommendations that newborn infants immediately receive a hepatitis B shot, shifting a decades-old standard that’s helped protect children from the potentially deadly complications that can arise from a common viral infection.

The influential committee, known as the Advisory Committee for Immunization Practices or ACIP, voted 8 to 3 to recommend what’s known as shared decision making when an expectant mother tests negative for the hepatitis B virus. Shared decision-making is a softer recommendation than a universal endorsement. For those who don’t receive the initial dose at birth, the panelists are advising a first shot no earlier than two months afterwards. 

A second vote advised parents to consult with health care providers to determine whether testing should be offered before a child receives a subsequent vaccine dose. This decision breaks with established science and also weakens the current guidelines universally supporting a three-shot regimen, which is believed to be critical in ensuring long-lasting protection from hepatitis B. It’s unclear how effective only one or two shots are.

“The hepatitis B vaccine program is one of the world’s greatest achievements in medical health in the protection of children,” said Joseph Hibbeln, a psychiatrist and neuroscientist and one of the dissenting panelists. “This has a great potential to cause harm, and I simply hope that the committee will accept its responsibility when the harm is caused,”

“We are going to experience increased rates of hepatitis B, and it is not the right thing for us to do,” added Cody Meissner, an expert in pediatric infectious disease epidemiology, vaccine development, and immunization safety. Meissner also voted against the new recommendations.

The hepatitis B virus can be transmitted from mother to newborn during birth, as well as through infected body fluids. Newborns are much more likely than those over the age of 5 to contract chronic infections, which can lead to progressive liver disease, cirrhosis or liver cancer later in life.

Women can be infected without realizing it and, while testing can be done during a prenatal visit, lack of access to healthcare facilities or errors during and after testing can prevent mothers from knowing their status. The Vaccine Integrity Project, an initiative started by a group at the University of Minnesota, found in a recent report that anywhere from 12% to 18% of women aren’t tested during pregnancy, and only 42% of pregnancies with a positive diagnosis received the recommended care. 

Vaccines for hepatitis B were first introduced in the 1980s, and ACIP in 1991 began recommending that all infants get the first of a three-shot regimen within 24 hours of birth. Since then, vaccination has proven to be more than 90% effective at inducing immunity, with protection lasting decades and possibly for life.

One study published by the Centers for Disease Control and Prevention in 2023 credited vaccines with spurring a 99% drop in infections among U.S. infants, children and young adults between 1990 and 2019. And a recent pre-print study from several U.S. institutions projected that delaying vaccinations by even two months after birth would lead to over 1,400 preventable infections, 304 cases of liver cancer and 482 related deaths. 

“The hepatitis B vaccine is the most effective way we have to prevent the infection in babies and prevent the subsequent liver failure and liver cancer later on in life,” said Kawsar Talaat, an infectious disease physician and associate professor in the Department of International Health at the Johns Hopkins Bloomberg School of Public Health, in an interview with BioPharma Dive. 

Department of Health and Human Services Secretary Robert F. Kennedy Jr. remade the committee last June, abruptly ousting all of its previous members and replacing them with panelists more aligned with his skeptical views of vaccines. The reformed panel has since made small inroads towards limiting vaccine access. After initially questioning the safety and impact of COVID vaccines, ACIP softened recommendations supporting use of the shots. It also voted to split MMR and varicella shots and recommended that a particular preservative be taken out of flu vaccines.

Several medical groups have spoken out against the reformed ACIP, with some organizations promoting their own vaccine recommendations. Previously ousted members of the group also called for the creation of a new alternative, citing its “inexperienced and biased” members.

In the past, CDC work groups would meet ahead of an ACIP meeting to prepare data briefings. However, working group members, as well as Debra Houry, the CDC’s former chief medical officer, have said these groups haven’t regularly convened, and experts on vaccine safety and development told Stat News they were not consulted ahead of the meeting. Presenters included a lawyer, Aaron Siri, who’s sued vaccine manufacturers, and Cynthia Nevison, a climate researcher with ties to anti-vaccine groups. 

“The ACIP is totally discredited. They are not protecting children,” Bill Cassidy, a Republican senator who helped confirm Kennedy as HHS Secretary, posted on the social media platform X.

The group met in September to discuss delaying newborns’ hepatitis B shot, with some citing potential safety risks and others expressing confusion as to why a change was being considered. They tabled a vote on the issue, leading to a new gathering months later. 

At the meeting’s start, Robert Malone, who served as committee chair for the proceedings, said the vote was delayed so more data could be gathered to guide the panel. “When gaps in the evidence emerge, the responsible action is not to push forward,” he said. 

Yet the committee struggled to move forward after hearing that evidence. 

In one presentation, Nevison argued that other, “targeted” measures had a greater impact on plummeting hepatitis B infection rates than a birth dose, and downplayed the regimen’s effectiveness at preventing disease long-term. Mark Blaxill, an anti-vaccine activist, contended that more safety data should be generated via new placebo-controlled clinical trials, echoing talking points from Kennedy. (Scientists have noted how testing a vaccine against a placebo, when an effective shot currently exists, could be considered unethical.)

Meissner was skeptical of both presentations, pointing to a lack of evidence that hepatitis B vaccines cause any meaningful harm, and noting how the disease has “gone down” in the U.S. because of the current immunization program.

“In your opinion,” Malone responded, prompting Meissner to quickly counter “those are facts.” 

Meissner was joined by a liaison to the American College of Physicians and representatives from hepatitis B vaccine manufacturers, GSK, Sanofi and Merck & Co. in defending the shots’ merits. The liaison, Jason Goldman, pleaded with the panel to “look at all evidence and data and not cherry-pick,” and company representatives argued that there’s no credible data pointing to safety risks. 

“Please have respect for the American public and the science and do what is right by making sure you use a process that we can depend on,” Goldman said.

Vinay Prasad, the controversial head of the Food and Drug Administration office that regulates vaccines and gene therapies, again left the agency this year.

Prasad’s departure ended a tumultuous tenure during which he reworked vaccine guidelines and appeared to set a higher bar for rare disease drug approvals. The announcement came only days after an unusual public spat between the agency and UniQure, the developer of one such rare disease treatment that has faced a longer road to approval than it had anticipated.  

In a statement on the social media platform X, Martin Makary — the former comissioner who has also since left the FDA — cited the “long-lasting reforms” Prasad helped instill over his tenure, from a new pathway for bespoke therapies to shortened pivotal trial requirements and a “national priority” drug review program. 

“I want to thank him for his service and personal sacrifice to take time away from his family,” Makary said, adding that the agency will name a successor before his departure. 

A prolific academic and longtime critic of U.S. drug policies, Prasad was named the head of the FDA’s Center for Biologics Evaluation and Research last May. At the time, Makary called his hiring a “significant step forward” for CBER, as Prasad brought the “scientific rigor, independence and transparency” the office needed, he claimed.

Makary later named Prasad as the FDA’s chief medical and scientific officer, in addition to his role at CBER.

Prasad was a vocal opponent of his predecessor Peter Marks, who ran CBER for nearly a decade before resigning last March. Marks championed regulatory flexibility while at the FDA and, as head of CBER, oversaw the review and approvals of COVID-19 vaccines as well as dozens of cell and gene therapies, earning praise and criticism along the way. Prasad previously condemned many of those decisions, and his appointment raised concerns among many biotech companies and investors that FDA standards might be shifting. 

After joining the FDA, Prasad helped establish stricter approval guidelines for COVID-19 vaccines. He then stepped in multiple times to overrule other agency reviewers in issuing narrower-than-requested clearances for COVID vaccines and, at one point, authored a memo warning that an investigation into COVID shots could be used to justify substantive changes to the way vaccines are regulated. 

Prasad was also behind the FDA’s decision to initially refuse to review a flu shot from Moderna before the agency quickly changed course amid public backlash. 

Like Makary, Prasad attempted to calm fears that the FDA might be less flexible under his watch in regulating gene therapies for rare conditions. At a round table meeting hosted by the FDA last year, he noted how progress “is not always made in a single leap” and that the agency would “consider incremental steps forward” too, “because those add up.” And he helped outline what’s now known as the “plausible mechanism” pathway, a new regulatory tool designed to accelerate the development of treatments for ultra-rare conditions. 

Yet over the course of Prasad’s tenure, multiple messy disputes arose between the agency and the developers of drug programs regulated by CBER. He left the agency for a few weeks last July following a public spat over the safety of Sarepta Therapeutics’ Duchenne muscular dystrophy gene therapy Elevidys. After his return, the FDA was accused by multiple drugmakers of flip-flopping on previous guidance in delaying or rejecting rare disease therapies, frustrating biotech companies and investors and fomenting a sense of unpredictability around agency decisionmaking. And Prasad reportedly intervened in multiple cases in which he’s been skeptical of company data.

The controversy escalated earlier this year, when the FDA demanded that the Dutch gene therapy maker UniQure run a new study before seeking approval of a treatment for Huntington’s disease. UniQure claimed that outcome represented a U-turn from what it was told previously. Days later the FDA, in unusual fashion, held a call with journalists and a high-ranking agency official who spoke on the condition of anonymity about UniQure’s case. 

During that call, the official criticized UniQure's therapy and accused the company of mischaracterizing talks with the agency — an account the company disputed. After this call became public knowledge, many speculated the official to be Prasad, and one member of Congress claimed he’d violated agency rules and federal law by discussing the case. Prasad’s departure, which Makary framed in his social media post as the end of a “one-year sabbatical,” was announced hours later. 

Prasad’s coming exit is “likely to be received positively,” wrote RBC Capital Markets analyst Brian Abrahams, in a note to clients. Shares of multiple rare disease developers, including UniQure, rose afterwards. 

But his departure “perpetuates the regulatory leadership volatility that has kept companies uncertain about their developmental direction and many investors on the sidelines,” Abrahams added. “Prasad's replacement — even if a bit more lenient — would likely still mirror” the views Makary and the agency currently have, he warned. 

Karim Mikhail, the former head of heart drug developer Amarin, has since been named CBER’s acting director.

Advisers to the Food and Drug Administration have thrown their support behind an experimental flu shot from Moderna, heightening the chance that the vaccine could soon complete a dramatic regulatory turnaround. 

By a unanimous, 9-0 vote, panelists concluded in June that the benefits of vaccination with Moderna’s mRNA-1010 outweigh the risks in adults between 50 and 64 years of age. Panelists separately all voted that the shot appeared similarly beneficial for adults aged 65 and older. Moderna is seeking standard approval for mRNA-1010 in the former group and an accelerated approval in the latter.

"The studies that were presented today were very well conducted. They have very clear results that are very robust," said Flor Munoz-Rivas, a panelist and associate professor of pediatrics and infectious disease at Baylor College of Medicine. Should the FDA approve Moderna's shot, the U.S. will be "better prepared for emerging strains or pandemic strains in the future." 

“The data were very convincing," added Stanley Perlman, a pediatric disease expert at the University of Iowa. "Putting it all together, the benefits outweigh the problems, the risks, in my opinion" 

The FDA does not always follow its panelists' advice, but it typically does. 

Like the rest of Moderna’s work, mRNA-1010 is built around messenger RNA technology with the kind of speed and manufacturing advantages that make it uniquely capable of battling emerging viral threats. Moderna rocketed to stardom by using that technology to develop a COVID-19 shot, and has long aimed to follow with another one for seasonal influenza — for which a speedily-made vaccine could be tailored to a given year’s prominent strains. Yet development hasn’t been straightforward, and Moderna even got in an unusual public dispute with the FDA along the way.  

Moderna has been working on mRNA-1010 as well as a combination shot for COVID and flu. The biotech originally sought approval for the dual-acting vaccine until the agency last year requested more data from its influenza component. 

After gathering that information, Moderna sought U.S. approval of mRNA-1010 alone. But in an unorthodox move, the agency declined to even review the application, with Vinay Prasad, the FDA’s top vaccine official at the time, contending that Moderna’s study wasn’t adequately controlled. Moderna published the letter along with a statement claiming the FDA had both backtracked on previous communications and went against established guidance for flu shots. The FDA quickly reversed course following public backlash and a formal meeting with Moderna. 

Since then, Prasad as well as former commissioner Marty Makary — both of whom had enacted stricter regulatory standards for certain vaccines — have left the agency. And on an interim basis, they’ve been replaced by what appears to be more traditional leadership. Already, a few drugs that had been rejected under Makary’s leadership have received a new chance, suggesting a shift in regulatory decision-making. 

Moderna’s case is now next in line. The company’s application is based on results published in the New England Journal of Medicine showing that the shot reduced the likelihood of influenza illness by 27% when compared to a standard-dose flu vaccine in adults 50 years of age or older. 

The performance of current flu vaccines is “variable,” said Rituparna Das, Moderna’s head of infectious and rare disease clinical development, at Thursday’s meeting. Moderna’s shot could “address important limitations” and improve protection in “a population that continues to experience substantial influenza burden.” 

Ahead of the meeting, FDA staff reviewers expressed concerns with what they considered to be gaps in the evidence supporting mRNA-1010’s benefits. Moderna accumulated efficacy data over the course of only one flu season, and didn’t clearly prove the vaccine’s effectiveness in frail older adults as well as immunocompromised individuals. Moderna also didn’t have data in people also receiving other respiratory vaccines, nor did it definitively establish efficacy against the influenza B strain, staff reviewers wrote. 

Still, multiple Wall Street analysts interpreted those arguments as a positive sign for Moderna. The documents revealed that the FDA identified “no major deficiencies,” boosting confidence in mRNA-1010’s approval prospects, wrote William Blair analyst Myles Minter in a Tuesday note. In a separate note, Leerink Partners’ Mani Foroohar, described the FDA analysis as indicative of a “less-harsh regulatory stance.” 

At the meeting, panelists voiced reservations about the trial’s short window and the small number of confirmed influenza B cases. That result occurred because of the severity of the 2024-2025 flu season. Moderna was aiming to evaluate efficacy after 836 cases and expected to accrue them over a longer period of time. It quickly captured 968 cases instead.

“We did miss an opportunity to really understand the performance of the product pre-licensure,” said panelist Hana El Sahly, professor of molecular virology and microbiology at the Baylor College of Medicine, during the meeting. “There’s a particular issue when a study is cut short,” she added.

Yet that issue didn’t lead any panelists to vote against Moderna’s vaccine. One reason is that Moderna has agreed to the framework of a confirmatory trial that could help compile the evidence that’s currently lacking. That study is meant to help verify mRNA-1010’s benefits in the elderly and those with weakened immune systems, and will involve up to 800,000 participants over the course of two flu seasons. 

This “very well planned and large” study will “address important questions,” Munoz-Rivas said.

No serious safety concerns were identified by either Moderna or FDA staff reviewers. Still, adverse reactions consistent with mRNA vaccines were recorded in the trial, including fatigue, joint pain and muscle aches. Given the public’s divisive reaction to mRNA shots in the wake of the pandemic, FDA panelists were adamant that the messaging about mRNA-1010’s positive impact will be important for uptake. 

“At least anecdotally, the same people who seem to have systemic reactions to the COVID vaccine seem to have them again,” El Sahly said. “We really need to be able to message why people should get this vaccine.” 

Das, of Moderna, said the company is working ahead of time with vaccinators to make sure they are educated on the data. 

“There's benefits and risks, and we do believe the benefits outweigh the risks,” she said. “But the communication is quite important.”

Vaccine sales for French pharmaceutical company Sanofi dipped in the fourth quarter of 2025 amid shifting U.S. policy and rhetoric that’s leading to declining immunization rates.  

In disclosing annual earnings in January, Sanofi revealed that its fourth-quarter vaccine sales declined 2.5% and that it anticipates “slightly negative growth” for its shots in 2026. Those calculations came despite better-than-expected global performance for its flu shots, which came during “a massive increase in terms of influenza and hospitalization across the north hemisphere,” Thomas Triomphe, Sanofi’s executive vice president of vaccines, said on a conference call. 

Flu vaccine performance, though, was offset by falling numbers for other immunizations, including a shot for meningitis and its preventive RSV antibody Beyfortus. Still, Sanofi is committed to investing in vaccines and pointed to a pair of acquisitions last year as evidence. Sanofi still maintains its “leadership in influenza and RSV despite a challenging environment,” CEO Paul Hudson told analysts.

Health and Human Services Secretary Robert F. Kennedy Jr. has helped upend U.S vaccine policy over the last year, in the process dampening the sales performance of multiple companies with marketed products.

Repeated false claims about the risks of vaccination, combined with an overhaul of the key panel guiding U.S. vaccine recommendations, have increased already growing hesitancy and spurred disease outbreaks. The biggest change came in January, when that panel, in response to a directive from President Trump, dialed back longstanding universal endorsements for childhood vaccinations. The CDC now recommends 11 vaccines over the previous 17, despite a lack of new evidence or public debate to support such a drastic change. 

The move has been condemned by several major medical organizations and ignored by others. An immunization schedule released by the American Academy of Pediatrics, for example, has gained backing from other prominent medical groups. Additionally, multiple states are now diverging from federal guidelines and relying on prior recommendations or state frameworks instead. 

"There could be some confusion," Triomphe said regarding the climate in the U.S. However, he said all vaccines remain covered by insurance, Medicaid or Medicare, and it’s unclear as of yet what kind of impact the U.S. government’s new recommendations will have on uptake.

Despite those challenges, Hudson noted that Sanofi will still invest heavily in future shots. The company acquired vaccine makers Vice Bio and Dynavax last year, deals that “reinforce our commitment to innovation in vaccines,” he said. 

Eli Lilly is diving into infectious disease research, announcing in May agreements to acquire a trio of vaccine developers for up to nearly $4 billion.

In three separate transactions, Lilly bought privately held vaccine makers Vaccine Co., Curevo and LimmaTech Biologics. Lilly didn’t detail the upfront payouts involved in any of those deals. But the Vaccine Co. and Cuervo purchases could be worth up to $1.55 and $1.5 billion, respectively, while the LimmaTech acquisition could total $780 million if certain milestones are met.

The buyouts add to an already active year for biotech company acquisitions and continues a dealmaking spree for Lilly specifically. Loaded with cash from its fast-selling obesity and diabetes drugs, Lilly has acquired 11 drugmakers so far this year alone in areas such as oncology, immunology, neurology, genetic medicine and now infectious disease.

While Lilly is best known for its cardiometabolic drugs, the company has at least some history in infectious disease. Decades ago, it played a key role helping distribute the polio vaccine and, more recently, it worked with AbCellera to develop antibody drugs for COVID-19. The latter effort yielded some short-term success, too, in the form of a pair of medications Lilly temporarily marketed a few years ago.

Now, though, the pharmaceutical giant appears to be eyeing infectious disease as a new way to branch out. It already employs a well-known leader, having hired Peter Marks, the Food and Drug Administration’s former vaccine chief, as its head of infectious disease last year. And Lilly noted upon acquiring the three vaccine makers that these disorders remain a “major source of global morbidity,” with common infections now linked to many conditions that can emerge later on.

The deals “reflect a deliberate strategy to prevent disease at its source rather than treat its consequences," said Daniel Skovronsky, Lilly’s chief scientific and product officer, in a statement.

Curevo’s lead asset is an experimental shingles vaccine using a “next-generation synthetic adjuvant” that might help address tolerability challenges with existing shingles shots. In Phase 2 testing, that vaccine spurred a similar immune response to a standard shot, but elicited fewer side effects, Lilly said.

LimmaTech has been working on vaccines for bacterial infections, a growing global health issue given the rise of antimicrobial resistance. Its lead program is in Phase 1 development for Staphylococcus aureus bacteria, a leading cause of surgical infections.

Vaccine Co., meanwhile, has a preclinical prospect for Epstein-Barr Virus, a pathogen linked to multiple sclerosis and several cancers. The startup won a grant from the Advanced Research Projects Agency for Health, or ARPA-H, in 2024.

French pharmaceutical giant Sanofi last July paid $1.15 billion to acquire the privately held London-based private biotechnology company Vicebio and its portfolio of experimental vaccines.

Through the deal, Sanofi gained a combination shot in clinical testing for protection against respiratory syncytial virus and human metapneumovirus, or hMPV. Vicebio specializes in a vaccine technology it dubs “molecular clamp.”

Sanofi is one of the largest vaccine manufacturers, and has found success with treatments for respiratory infections such as influenza and RSV. An antibody drug, Beyfortus, that Sanofi developed with partner AstraZeneca has become a blockbuster product for preventing RSV disease in infants.

However, Sanofi has also been looking to broaden its vaccine portfolio to include other, non-mRNA technologies. Last year, the French pharma partnered with Novavax, gaining rights to co-market its protein-based COVID shot. And now, the acquisition of Vicebio could bolster its pipeline with new options to treat respiratory infections.

Vicebio’s lead candidate, dubbed VXB-241, could allow Sanofi to “offer increased physician and patient choice in RSV and hMPV by adding a non-mRNA vaccine to its pipeline,” the company said in a statement. VXB-241 is currently in Phase 1 testing.

Leerink Partners analyst David Risinger wrote in a client note that the deal is evidence of Sanofi’s “enthusiasm for developing protein-based combination vaccines.”

Vicebio also has another candidate in preclinical development against RSV, hMPV and parainfluenza virus Type 3, a respiratory infection that commonly infects children and can lead to bronchitis or pneumonia.

The biotech uses technology developed by researchers at Australia’s University of Queensland. This “molecular clamp” platform is designed to elicit strong immune responses against respiratory diseases, while permitting simpler and faster production and distribution.

“This opens the door to user-friendly formats such as pre-filled syringes and supports efficient, large-scale manufacturing,” Vicebio CEO Emmanuel Hanon, wrote in an email.

Vicebio was formed by European life sciences investment firm Medicxi in 2018. The University of Queensland remains an investor.

“[This acquisition] significantly increases the likelihood of seeing our innovation reach the market, ultimately benefiting patients and supporting the efforts of public health authorities,” Hanon added.

GSK’s respiratory syncytial virus shot gained an expanded approval in March from the Food and Drug Administration, a decision that represented a victory in what’s been a difficult regulatory climate for vaccine makers of late.

The vaccine, Arexvy, was first approved for use in adults aged 60 and older, and then those 50 to 59 years of age and at higher risk of severe RSV-related disease. The March approval expanded its potential use significantly, opening it up to what GSK estimates to be 21 million Americans who are under 50 and have at least one risk factor for severe disease. It also heightened Arexvy’s competition with Pfizer’s Abrysvo and Moderna’s mResvia, ‌which are approved for the same population.

RSV is a leading cause of respiratory illness and can cause severe health complications in infants, the elderly and people with weakened immune systems. In a statement, GSK noted that RSV also causes about 17,000 hospitalizations, 277,000 emergency department admissions and 1.97 million outpatient visits each year in younger adults. Most of those hospital stays involve people with chronic medical conditions that put them at higher risk of severe disease, according to GSK. And some studies have indicated that cases for people with underlying medical problems may be underreported.

“This age expansion can help address a significant medical need for adults in the United States at higher risk of severe RSV disease due to certain underlying conditions, and help ease pressure on the healthcare system,” said Sanjay Gurunathan, GSK’s head of vaccines and infectious research and development, in the statement.

GSK was the first company to win approval of an RSV vaccine and has since held a commanding market share. But after an initially strong launch, sales have been slipping amid falling demand, particularly in the U.S. The Centers for Disease Control and Prevention has yet to endorse RSV booster shots, limiting Arexvy’s sales potential.

Like other vaccine developers, GSK faces slowing sales in the U.S., where the federal government has taken a more combative stance against immunizations under the leadership of Health and Human Services Secretary Robert F. Kennedy Jr. The CDC rolled back what had been universal endorsements for the childhood vaccine schedule, while the Food and Drug Administration set stricter guidelines for vaccine approvals.

Still, there are signs of a potentially friendlier stance in the months ahead. Vinay Prasad, the FDA’s top vaccine official, left the agency at the end of April. And of late, multiple published reports suggested the Trump administration is shying away from more vaccine policy changes amid polling suggesting it could damage Republicans in the midterms.

Vaccine policy may “remain a source of regulatory and political volatility near-term,” but the focus might “increasingly center on cost of care, nutrition, and chronic disease initiatives,” wrote Leerink Partners analyst David Risinger, in a note to clients.

GSK said the approval was based on study data showing the immune response generated by Arevxy in younger adults was as good as what was observed in testing in older individuals. Safety was also consistent with what was previously seen in testing.

The Food and Drug Administration in mid-June approved a new vaccine from Merck & Co. that protects against 21 types of the bacteria that causes pneumococcal disease.

The vaccine, cleared for use in adults 18 and older, will be sold by Merck as Capvaxive. Pneumococcal disease can lead to severe infection in the lungs or sometimes in the blood and spinal cord, when it is known as meningitis. Adults older than 65 or who have compromised immune systems are at particular risk for the disease.

Merck currently sells two pneumococcal vaccines. One, dubbed Pneumovax 23, is for adults at least 50 years of age and children older than two who are increased risk of infection. The other, Vaxneuvance, is for those aged six weeks and older.

But it’s Pfizer’s Prevnar shots that have dominanted the market. The company’s Prevnar 20 gained approval in 2021 for adults 18 years or older and is now also cleared for infants and teenagers. The vaccine protects against 20 serotypes, while Merck’s Vaxneuvance covers 15.

Capvaxive could have an edge there, as it targets 21 serotypes, including eight not covered by other shots.

“[Capvaxive] will be the first approved pneumococcal conjugate vaccine specifically designed to help protect against the serotypes that cause the majority of invasive pneumococcal disease in adults,” wrote Paula Annunziato, vice president of vaccine clinical development at Merck, in an email to BioPharma Dive. “It covers the serotypes responsible for ~84% of cases of [invasive pneumococcal disease] in adults 50 years and older.”

The comparator number for Prevnar 20 is 52%, per Merck. And according to the company, the eight unique serotypes covered by Capvaxive alone account for more than one-quarter of invasive pneumococcal disease cases in adults 50 years and older.

Merck set the price of Capvaxive at $287 per the single dose used for immunization. In a statement, Merck said most people in the U.S. would have access at no out-of-pocket cost following a CDC recommenation.