The World Health Organization (WHO) has condemned a planned clinical trial in Guinea-Bissau, funded by the U.S. Centers for Disease Control and Prevention (CDC), as “unethical,” halting the study which proposed differing timelines for administering the hepatitis B vaccine to newborns. The trial, valued at $1.6 million (£1.2 million), aimed to assess the effects of delaying the vaccine from birth to six weeks of age.
The WHO’s criticism centers on the study’s design, which would have provided the hepatitis B birth dose vaccine to some infants even as withholding it from others, exposing the latter group to potential risks. According to a statement released Friday, the organization has “significant concerns” regarding the study’s scientific justification, ethical safeguards, and alignment with established principles for research involving human participants.
“A study which provides the hepatitis B birth dose vaccine, a proven lifesaving intervention, but withholds it from some study participants exposes newborns to serious and potentially irreversible harm, including chronic infection, cirrhosis, and liver cancer,” the WHO stated. The organization emphasized that the hepatitis B birth dose vaccine has been utilized for over three decades in more than 115 countries and is known to prevent 70–95% of mother-to-child transmissions of the virus.
The CDC-funded trial sought to investigate broader health effects of the vaccine, a move reportedly influenced by Robert F. Kennedy Jr., the current head of the U.S. Department of Health and Human Services, who has previously expressed skepticism about vaccine efficacy and safety. The WHO argues that trials withholding a proven intervention are only justifiable when no effective treatment exists, a condition it asserts is not met in the case of the hepatitis B birth dose vaccine.
Guinea-Bissau has a substantial population affected by hepatitis B, with the WHO recommending universal vaccination at birth to prevent mother-to-baby transmission. The organization maintains that delaying vaccination increases the risk of lifelong infection, with 90% of newborns infected at birth becoming chronic carriers.
The WHO’s statement underscores the established recommendation that all newborns receive the hepatitis B vaccine within 24 hours of birth. The proposed trial’s design, directly contradicts this guidance and raises serious ethical questions about exposing vulnerable infants to preventable harm.
As of Saturday, the CDC has not publicly responded to the WHO’s condemnation. The future of the funding for the trial remains uncertain, and the WHO has not indicated whether it will pursue further action beyond its public statement.
