A proposed $1.6 million study on the hepatitis B vaccine in Guinea-Bissau, funded by Robert F. Kennedy Jr. and the U.S. Department of Health and Human Services (HHS), has been halted by the Africa Centres for Disease Control and Prevention (CDC) due to ethical concerns regarding its design. The study aimed to investigate potential long-term neurological issues related to the vaccine in 14,000 newborns by comparing different vaccination schedules.
Background of the Study
The study, initially slated to commence on January 5, was designed to observe 14,000 newborns in Guinea-Bissau over five years. Participants would have been divided into two groups: one receiving the hepatitis B vaccine at birth, aligning with World Health Organization (WHO) recommendations, and another receiving it at six weeks of age, consistent with Guinea-Bissau's current local practice. The research aimed to investigate potential long-term neurological issues related to the hepatitis B vaccine. Guinea-Bissau has a significant prevalence of hepatitis B, with approximately 18% of adults and 11% of children under one year infected. The country plans to implement a universal birth dose program for infants by 2027.
Ethical Concerns and Criticism
The proposed study design drew criticism from various individuals and organizations, including the Africa CDC. Key concerns raised included:
- Vaccine Withholding: Critics argued that the study would knowingly delay the birth dose vaccine for up to 7,000 children in a region with a high risk of early life hepatitis B infection, potentially increasing their risk of infection. Infectious diseases physician Paul Offit suggested the funding could be used for direct vaccination instead.
- Study Objectives: The study was not designed to assess the efficacy of early versus delayed vaccination, a benefit that is scientifically established. The development of chronic liver disease from perinatal hepatitis B infection typically manifests over several decades, potentially exceeding the study's five-year timeline.
- Blinding: The study was structured as single-blinded, meaning investigators would be aware of which group participants belonged to, but parents would not. This raised questions about potential investigator bias in assessing outcomes.
- Consent Process: Concerns were voiced regarding whether the consent process for parents would clearly outline the risks associated with delayed vaccination for the 6-week group.
- Investigator Selection and Affiliations: The selection of Danish researchers Peter Aaby and Christine Stabell Benn occurred outside the standard bidding process. Christine Benn has acknowledged associations with groups critical of vaccines in the United States. Aaby and Benn had previously co-authored a study suggesting a link between the DTP vaccine and premature deaths, a finding they later retracted. Critics like Boghuma Titanji, an assistant professor at Emory University, described the study design as exploitative of vaccine scarcity and governmental capacity in Africa.
- Historical Parallels: Some critics drew parallels between the study's design and the historical "Tuskegee Study of Untreated Syphilis in the Negro Male" (1932-1972) in the United States, where life-saving antibiotics were withheld from participants.
Africa CDC's Decision and Future Discussions
Yap Boum, a senior official at the Africa CDC, announced the cancellation of the study, citing critical questions regarding its ethical design. He stated that evidence for policy translation must adhere to ethical norms. The Africa CDC indicated that the trial would only proceed if redesigned to address these ethical issues.
While some officials in Guinea-Bissau reportedly stated the trial would still occur, Africa CDC officials clarified that ongoing conversations between Guinea-Bissau and the U.S. are focused on how to conduct such a trial ethically. Africa CDC has assembled a team to support Guinea-Bissau in ensuring any future study complies with ethical regulations.
Researchers' Arguments
The Danish researchers, Peter Aaby and Christine Stabell Benn, had previously disputed ethical concerns about their study design. They argued that the trial would provide the vaccine to some newborns who might not otherwise receive it. They also posited that certain vaccines might interfere with "non-specific effects" of other vaccines, a claim based on their prior research that has been questioned by other Danish researchers.