Guinea-Bissau halts US-funded hepatitis B vaccine trial for newborns

Guinea-Bissau has halted a US-funded hepatitis B vaccine trial that would have enrolled 14,000 newborns, after health experts objected to delaying a World Health Organization-recommended shot for half the babies. A researcher involved in the project said it did not receive the necessary government approval.

The study, planned by the Bandim Health Project in the capital, Bissau, would have randomly assigned babies to receive the vaccine at birth or follow Guinea-Bissau’s current schedule, under which children receive it at six weeks. Researchers intended to compare health outcomes over five years, Al Jazeera reported. No babies were enrolled and no vaccinations were administered as part of the trial, University of Southern Denmark dean Jakob Grauslund told the BBC.

The US Centers for Disease Control and Prevention awarded the University of Southern Denmark $1.6 million for the project in December 2025. The funding came under US Health Secretary Robert F Kennedy Jr, who has expressed scepticism about vaccines.

Bandim’s researchers said they wanted to investigate whether a birth dose has health effects beyond preventing hepatitis B. Christine Stabell Benn and Peter Aaby, who lead the project, said they were examining “whether the prevention [of the disease] comes at a prohibitive price”, including possible effects on mortality and other health outcomes. They argued that Guinea-Bissau’s lack of a routine birth dose offered an opportunity to study those questions before its planned introduction in 2028.

Critics said that approach would leave thousands of babies without protection at birth in a country where roughly one-fifth of the population has hepatitis B. The virus can pass from mother to child during childbirth, and infection in infancy carries a particularly high risk of becoming chronic. WHO representative Walter Kazadi Mulombo told the BBC the vaccine had been used for more than 30 years in over 115 countries. “A study that will withhold that intervention from other newborns is unethical,” he said.

Former Guinea-Bissau health minister Magda Robalo likewise told Al Jazeera: “It is unethical to deny children an intervention that we know works.” Duke University global health professor Gavin Yamey called the proposed trial “neocolonial” in comments to the BBC, questioning why it was not being conducted in Denmark.

Guinea-Bissau’s government prohibited hepatitis B vaccine trials involving children in January and sought help from the Africa Centres for Disease Control and Prevention to review the proposal. The University of Southern Denmark later said a revised protocol had received ethical approval from relevant authorities in Guinea-Bissau. Health Minister Quinhin Nantote denied that the suspension had been lifted. Grauslund said the university’s own ethics committee had assessed the project positively, but that its decision could not replace authorisation from Guinea-Bissau.

On October 19, judicial police searched Bandim’s facilities and seized hepatitis B vaccines. Police did not disclose the number of doses or explicitly link the seizure to the proposed trial; they said it did not mean the vaccines were defective or unsafe, according to the BBC.

“It is now clear that the hepatitis B-NSE trial will not move forward in Guinea-Bissau — we were not given the necessary governmental approval,” Bandim researcher Frederik Schaltz-Buchholzer wrote in a post cited by Al Jazeera. He called the outcome a “significant setback” for African science. The WHO told the BBC it was working with the government to bring forward the routine birth dose, possibly to the first quarter of next year.