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Geneva, February 29, 2024
WHO Raises Ethical Concerns Over Hepatitis B Vaccine Trial in Guinea-Bissau
The World Health Organization is questioning the ethics of a study in Guinea-Bissau that withholds a proven, life-saving hepatitis B vaccine from some newborns.
- The WHO has voiced significant concerns regarding a randomized controlled trial (RCT) on the hepatitis B birth dose vaccine in Guinea-Bissau.
- The primary concern centers on the ethical implications of withholding a proven, effective vaccine from a portion of study participants.
- The WHO emphasizes that placebo-controlled trials are inappropriate when effective interventions already exist.
- Guinea-Bissau has suspended the study pending further review, and the WHO is offering support.
The hepatitis B birth dose vaccine is a remarkably effective public health tool, preventing life-threatening liver disease by stopping mother-to-child transmission at birth. For over three decades, more than 115 countries have included it in their national immunization schedules, recognizing its crucial role in protecting newborns and working towards global elimination efforts. The vaccine is known to prevent 70–95% of mother-to-child transmissions of hepatitis B, making it a cornerstone of preventative care.
Why Withholding the Vaccine Raises Ethical Red Flags
The WHO is responding to questions regarding a proposed randomized controlled trial (RCT) in Guinea-Bissau. After reviewing publicly available information and consulting with experts, the organization has expressed substantial concerns about the study’s scientific basis, ethical safeguards, and alignment with established research principles.
At the heart of the issue is the ethical dilemma of withholding a proven intervention. Providing the hepatitis B birth dose vaccine to some newborns while denying it to others exposes those in the latter group to serious, potentially irreversible harm. This includes the risk of chronic infection, cirrhosis, and liver cancer.
According to the WHO, placebo or no-treatment trials are only justifiable when no proven intervention exists or when such a design is essential to answer a critical question about efficacy or safety. Publicly available descriptions of the Guinea-Bissau study do not appear to meet either of these conditions. The study doesn’t question the vaccine’s effectiveness but instead focuses on hypothetical safety concerns without sufficient evidence to warrant the risk to participants.
Did you know? Transmission at birth is the most common route to lifelong hepatitis B infection; approximately 90% of newborns infected during childbirth become chronic carriers, facing a heightened risk of cirrhosis and liver cancer.
The WHO also points to a potentially biased study design – a single-blind, no-treatment-controlled approach – which could significantly limit the interpretability and policy relevance of the results. Furthermore, the organization stresses that resource constraints cannot justify withholding proven care in research involving vulnerable populations.
Guinea-Bissau’s Response and WHO Support
The WHO reports that Guinea-Bissau has suspended the study while conducting further technical reviews. The organization stands ready to support Guinea-Bissau in moving forward and accelerating the introduction of the birth dose vaccine, as well as strengthening implementation through:
- birth-dose delivery within 24 hours (including strategies for home and facility births);
- antenatal screening for hepatitis B surface antigen (HBsAg), linkage to care, and neonatal prophylaxis;
- cold-chain, last-mile logistics, and midwife/HCW training; and
- monitoring of timeliness and coverage, pharmacovigilance, and data use for continuous improvement.
The WHO remains dedicated to ensuring that all newborns – in Guinea-Bissau and globally – receive timely, evidence-based protection against hepatitis B, and that all research in this area adheres to the highest ethical and scientific standards.
Editor’s note
Hepatitis B is a significant global health threat, causing hundreds of thousands of deaths annually. In Guinea-Bissau, over 12% of adults are estimated to be living with chronic hepatitis B (2022), and infection rates in children under five (~2% in 2020) are considerably higher than the global target (≤0.1%). Guinea-Bissau’s recent decision in 2024 to add the hepatitis B birth dose to its national schedule, with planned implementation by 2028, underscores the vaccine’s value and reinforces the ethical imperative to protect newborns.
