This past week has brought a dizzying back-and-forth about a U.S.-funded medical research trial.
Many public health experts call the study unethical and unnecessary, likening it to the infamous Tuskegee Experiment, while the Trump Administration has promoted it as a rare opportunity to study the potential negative effects of a vaccine.
The randomized controlled trial — funded partly with $1.6 million from the U.S. Centers for Disease Control and Prevention — would study the general health effects of the hepatitis B vaccine given at birth in the west African country of Guinea-Bissau.
For a relatively small study in a relatively remote place, there has been outsized attention, and the rumor mill has been spinning. There have been contradictory reports that the trial has already started, that it has been canceled and that it's proceeding as planned.
This morning at a press conference, the Minister of Public Health in Guinea-Bissau, Quinhin Nantote, finally weighed in, saying the study is suspended pending review.
"We decided to suspend or even cancel the above mentioned study," said Nantote, who was speaking in Portuguese, through an interpreter. He said a local ethics committee that had approved the study did not have the "required technical resources" and did not coordinate with the necessary other medical authorities in the country. The country experienced a military coup in November last year and many high level officials changed in the process.
Nantote said the ethics review was the "consequence of misinformation, weak social communication means and a lack of international communication, leading to inappropriate interpretations of our national health policies regarding immunization and health studies." He added that there has "been no sufficient coordination in order to take a final decision regarding that study."
Africa CDC, the health agency of the African Union, says it is sending a team to Guinea-Bissau to help the country evaluate the study. It says that local officials have the final authority.
"It's not a foreign country that will come and say this one will take place. It's the sovereignty of the country," says Dr. Jean Kaseya, director-general of Africa CDC.
Immediately following the Thursday press conference, speaking on the condition of anonymity, an official with the U.S. Department of Health and Human Services sent an email to NPR that contradicted Nantote and Kasaya, asserting that the study has not been suspended.
Here's a look at why this trial has garnered so much attention.
This study is happening as U.S. vaccine policy changes
For more than 30 years, giving the hepatitis B vaccine to all newborns in the U.S. has been standard practice. It's also the recommendation of the World Health Organization.
The vaccine helps prevent infants from getting the hepatitis B virus from their mothers during delivery. The virus attacks the liver and can, years later, lead to cirrhosis, liver cancer and death. There's no known cure.
However, on December 5, CDC advisers voted to overturn the U.S. policy.
The advisers — hand-picked by vaccine-skeptic and Health and Human Services Secretary Robert F. Kennedy Jr. — worried the vaccine might cause some harm. However, outside medical groups point to numerous studies showing that it's safe and that rates of pediatric hepatitis B virus have dropped by 99% since 1991 and the CDC reported that in 2020 only 10 children in the U.S. got hepatitis B from exposure at birth.
Less than two weeks after the vote, a document emerged detailing that the CDC would fund a study to look into the hepatitis B vaccine in Guinea-Bissau, where nearly one in five adults are infected with hepatitis B virus. That rate is much higher than elsewhere in sub-Saharan Africa where the prevalence is just around 6%, according to the Africa CDC.
The basics of the study
Guinea-Bissau does not currently give the hepatitis B vaccine to newborns per the WHO recommendation but plans to start doing so in 2028, according to Guinea-Bissau's Nantote.
Danish researchers say on their website that they want to study 14,500 newborns during this "unique window of opportunity" before the birth vaccination starts. Half of newborns will get the hepatitis B vaccine at birth, while the other half would get the inoculation later as part of other routine vaccinations given at 6, 10 and 14 weeks old.
The idea is not to test whether the hepatitis B vaccine works against hepatitis B. Instead, the researchers are looking for other health effects of the vaccine. Do the newborns who get the vaccine develop other severe illnesses in the first few weeks of life? Do they get eczema in the first two years of life? Or perhaps they show neurological differences before they turn 5?
The ethics: unethical and unnecessary?
Not long after the study surfaced physicians and medical ethicists called for its cancellation.
"[The Guinea-Bissau study] is highly unethical and cruel and frankly dishonest," says Dr. Paul Offit, director of the Vaccine Education Center at the Children's Hospital of Philadelphia and formerly a member of the CDC's Advisory Committee on Immunization Practices.
He's one of a number of physicians who have compared this study to the notorious Tuskegee Experiment, which started in the 1930s and, for decades, denied treatment to poor African Americans with syphilis so that researchers could see how the disease progresses. More than 100 died as a result.
"The 7,000 group that's not getting the vaccine till six weeks of age are now being exposed to substandard care — substandard care that is being paid for by American tax dollars," Offit says, noting that with such a high rate of hepatitis B virus in the population many of those youngers could be infected by their mothers before 6 weeks of age.
Dr. Boghuma Titanji, an infectious disease physician at Emory University, agrees with the Tuskegee analogy and worries the study could be the "initial trigger that then leads to communities being distrustful of medical intervention and vaccines." She says that distrust can last decades and even be passed down from generation to generation.
The researchers behind the study counter that, currently, newborns in Guinea-Bissau are not getting the vaccine at birth.
"No newborn in Guinea-Bissau will receive fewer vaccines because of this study," they wrote on their website, defending their study. They foresee that "vaccination coverage will increase" explaining "trial vaccination teams will operate every day of the year, including weekends and holidays. This is expected to increase timely vaccination coverage compared with routine services." The researcher did not respond to NPR's multiple requests for comment about the ethical questions and whether the study has been canceled.
Some bioethicists say there's a more fundamental issue: "The first and important consideration in making a study ethical is: The study has to answer a valuable question," says Christine Grady, former chief of the Department of Bioethics at the National Institutes of Health Clinical Center. "In this case, I think that's perhaps the biggest problem with this study," she says, noting that the vaccine has long been known to be safe and effective.
The researchers argue on their website that the results "will contribute to the global scientific understanding of how vaccination affects overall child health" and that "this is an important trial which can impact future vaccine policies in the region and worldwide."
The politics: Non-competitive, questionable researchers
Another major point of contention: who is doing the research and how they were selected.
The Danish researchers at the helm — including Dr. Christine Stabell Benn — are highly controversial. They are affiliated with the University of Southern Denmark and lead the Bandim Health Project, which has done research in Guinea-Bissau for decades.
While work by Stabell Benn's team has been published in reputable scientific journals, their statistical work has been questioned. For example, last month, in the journal Vaccine, outside biostatisticians evaluated the studies coming out of Bandim Health. What they found was that the group has "systematically over-interpreted the findings from their randomized trials," meaning the conclusions have been overstated and often aren't backed up by the data when there was "proper statistical handling." That's according to a press release accompanying the article.
"I was surprised by some quite strong claims," explains Henrik Støvring, a professor of pharmacometrics and statistics at Denmark's Aarhus University and lead author on the article. "But whenever I looked at a randomized trial — the primary outcomes I could find — it did not show statistical significance."
Stabell Benn's team has pushed back against this conclusion and requested the review be retracted by the journal. The request is being reviewed.
Still, RFK Jr. is a fan of Stabell Benn's team.
He cited a widely-criticized study on vaccine safety by Stabell Benn and others when he pulled more than a billion dollars in U.S. funding for Gavi, the Vaccine Alliance. That money would have helped fund childhood vaccinations in many low-resources settings. The anti-vaccine organization RFK Jr. chaired — Children's Health Defense — also cites the Danish researchers.
Outside vaccine experts have raised another concern: that the CDC awarded the $1.6 million dollars without an open, competitive process.
That's led Angela Rasmussen, a virologist at the University of Saskatchewan, to worry that the Bandim Health Project was hand-picked by RFK Jr.'s team to do the research, since they are known to have raised safety concerns about vaccines long considered safe.
"[The thing] people really need to know [is] behind this all — is cronyism, is bad science," she says. "It's babies getting chronic illnesses that can kill them."
In a statement to NPR, the U.S. HHS defended the study and said it is proceeding as planned and the protocol is being finalized. Their statement said the study "represents the world's first and perhaps only opportunity to test the overall health effects of [the hepatitis B vaccine at birth]."
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