FDA Blocks Publication of Vaccine Safety Studies: Why Experts Say Transparency Matters for Public Trust

The U.S. Food and Drug Administration (FDA) has halted the publication of several government-funded studies that looked at the safety and effectiveness of widely used COVID-19 and shingles vaccines. The decision, first reported by The New York Times, has sparked strong concern among infectious disease doctors and public health experts.

The studies involved millions of patient records and were conducted by FDA scientists and outside data contractors. Two studies on COVID-19 vaccines had already been accepted by medical journals but were withdrawn in October 2025 before they could be published. Two additional studies on the shingles vaccine Shingrix were also blocked from being submitted to a drug safety conference.

The Department of Health and Human Services (HHS), which oversees the FDA, confirmed the decision. An HHS spokesperson told The New York Times that the studies were blocked because of concerns about their conclusions. However, experts interviewed for this article say that explanation does not hold up under scrutiny.

“Scientists and physicians aren’t buying that explanation,” said Dr. Robert Glatter, an emergency medicine physician at Lenox Hill Hospital in New York City and assistant professor at the Zucker School of Medicine. “The public health implications of blocking such studies are serious. Secrecy can backfire. People who are already distrustful may see suppression where officials see caution.”

What the Blocked Studies Found

The COVID-19 vaccine safety studies reviewed side effects among millions of people. Researchers used data from Medicare and other large insurance databases to track what happened to people who received the vaccine. One study looked at adults aged 65 and older. Another examined people aged 6 to 64 years. Both found the vaccines to be safe.

The shingles vaccine study examined how well Shingrix works at preventing shingles, a painful viral condition that causes a blistering rash. Shingles is caused by the same virus that causes chickenpox. It can reactivate later in life, especially in older adults or people with weakened immune systems.

All of these studies were conducted using well-established methods. They were peer-reviewed, meaning other scientists examined the research before it was accepted for publication. According to experts, that process is the gold standard for ensuring scientific quality.

“The COVID-19 vaccine safety studies had been peer reviewed and would have been extremely important to be published for reassurance of the public of the safety of these vaccines,” said Dr. Monica Gandhi, a professor of medicine at the University of California, San Francisco.

Why Experts Are So Concerned

To understand why this matters, it helps to know a little background. Vaccines are among the most studied medical interventions in history. Before any vaccine is approved for public use, it goes through multiple phases of clinical trials involving thousands of people. After approval, federal agencies like the FDA continue to monitor safety through large databases that track millions of people in real time.

The COVID-19 vaccines, in particular, are among the most studied vaccines ever created. A massive body of evidence — from clinical trials, real-world data, and ongoing monitoring — consistently shows that the benefits of these vaccines far outweigh any rare risks. The same is true for the shingles vaccine, which has been used safely for years.

So why would the government block studies that confirm what we already know? Experts say the problem is not about the science — it is about the principle of transparency.

“The broad reaction from my colleagues and myself is skepticism and outrage toward the decision itself,” Dr. Glatter said. “Withholding research is viewed as unethical and irresponsible.”

In normal scientific practice, disagreements about research are handled through peer review, editorial commentary, and publication of rebuttals — not by stopping publication altogether. That process allows other scientists to examine the data, question the methods, and come to their own conclusions.

“No single study or method is perfect,” said Dr. William Schaffner, a professor of preventive medicine and infectious diseases at Vanderbilt University Medical Center. “It’s the assemblage of many different studies done by different investigators using methods that are sometimes slightly different, but that nonetheless have a long track record of reliability. That’s how we come to a consensus on effectiveness and safety.”

How This Affects You

If you are someone who has received a COVID-19 vaccine or the shingles vaccine — or if you are considering getting one — this decision may feel confusing or unsettling. You might wonder: If the government is hiding data, does that mean the vaccines are not safe?

Experts say no. The safety of these vaccines is supported by years of evidence from around the world. The blocked studies would have added even more evidence to an already strong foundation. But the act of blocking them can create doubt where none should exist.

“The public health implications are to erode trust in vaccines such as those used for COVID-19 and shingles prevention,” Dr. Gandhi said. “The public can be reassured by large database-based studies such as these on the safety and effectiveness of vaccines.”

When trust in vaccines erodes, fewer people get vaccinated. That can lead to outbreaks of preventable diseases. Shingles, for example, can cause long-term nerve pain that lasts for months or even years. COVID-19 can cause severe illness, long-term complications, and death, especially in older adults and people with underlying health conditions.

“Over the last several years, there’s been a great deal of controversy and concern about the effectiveness and the safety of vaccines,” Dr. Schaffner said. “Having data from very large real-life experiences assembled, analyzed, and then published is very important.”

That information goes to doctors, nurses, and pharmacists so they can honestly and clearly explain the benefits and risks of vaccines to their patients. Without it, healthcare providers have one less tool to answer questions and address concerns.

Could There Ever Be a Legitimate Reason to Block a Study?

Experts acknowledge that, in theory, there could be valid reasons to delay publication of a government-funded study. For example, if the study had serious methodological flaws, premature conclusions, or conflicts with stronger evidence, those would be grounds for internal review.

But that is not what happened here, according to the experts interviewed.

“Such conversations should happen in the open,” Dr. Glatter said. “Scientists revise, resubmit, respond to peer critique and review. What allegedly happened here — leadership halting accepted research without transparent scientific justification — falls well outside normal regulatory conduct.”

Dr. Gandhi went further, saying the decision “suggests a political rather than a scientific motivation and aligns with the anti-vaccine views of the Secretary of the Department of Health and Human Services, Robert F. Kennedy Jr.”

Under Secretary Kennedy’s leadership, HHS has already taken several steps that experts say weaken vaccine policy. These include softening COVID-19 vaccine recommendations, cutting vaccine research funding, and attempting to overhaul the childhood immunization schedule.

“Each of these steps, individually, might be debated on policy grounds,” Dr. Glatter said. “Together, and now compounded by the suppression of internally favorable safety data, they form a pattern that the public is right to scrutinize.”

What Experts Want to Happen Next

All three experts agree on one thing: These studies should be published as quickly as possible.

“I hope these studies are published as quickly as possible, because the information is important,” Dr. Schaffner said. “They both reinforce the effectiveness and the safety of one of the COVID vaccines and also the shingles vaccine.”

Dr. Gandhi echoed that sentiment. “I very much hope the FDA will reverse its decision and publish the studies. This matters deeply to public perception that the agency is upholding its formerly high standard of scientific integrity and is not compromised by the HHS Secretary’s ideological views.”

Dr. Glatter emphasized that the issue is not about needing more proof that these vaccines are safe. It is about protecting the process of science itself.

“The bottom line is that these studies should be published,” he said. “Not because we need more evidence that COVID and shingles vaccines are safe — we already have it — but because the act of suppression is itself the problem. Science earns public trust through transparency, including the willingness to publish findings that challenge assumptions.”

Practical Takeaways for Readers

If you are trying to make sense of this news and decide what it means for your health, here are some key points to keep in mind:

– The vaccines are safe. The scientific evidence supporting the safety of COVID-19 and shingles vaccines is overwhelming and comes from multiple sources, including large clinical trials, real-world data, and ongoing monitoring systems.

• The blocked studies were confirmatory, not groundbreaking. They would have added to an already strong body of evidence. Their absence does not mean the vaccines are unsafe.
• Trust is built through transparency. Experts are concerned that blocking these studies will erode public confidence in vaccines, which can lead to lower vaccination rates and more preventable illness.
• Talk to your doctor. If you have questions about vaccines, your healthcare provider is the best source of personalized advice. They can help you weigh the risks and benefits based on your individual health history.
• Stay informed, but be skeptical of sources. Misinformation spreads quickly, especially on social media. Look for information from trusted sources like the CDC, FDA, and major medical organizations.

The Bottom Line

The FDA’s decision to block publication of these vaccine safety studies has alarmed experts who say it undermines the very principles of scientific transparency that build public trust. While the vaccines themselves remain safe and effective based on decades of research, the act of suppressing data — even data that confirms what we already know — can do lasting damage to vaccine confidence.

“When the government funds research and then buries its own reassuring conclusions, it doesn’t protect scientific integrity — it damages it,” Dr. Glatter said. “And in a moment when vaccine hesitancy is already elevated, that damage doesn’t stay within the walls of a federal agency. It spreads like wildfire.”

The experts call on the FDA to reverse course, release these findings through normal peer review, and let the data speak for itself. That, they say, is what the data was intended to do.

Source: Healthline