CDC-funded hepatitis B vaccine trial in Guinea-Bissau paused amid ethical concerns

The U.S. Centers for Disease Control and Prevention awarded a $1.6 million grant to a Danish research group to compare hepatitis B vaccination at birth versus at six weeks in infants from Guinea‑Bissau. The five‑year study was designed to assess outcomes in a country with high hepatitis B prevalence and low vaccination coverage.

Critics argued that the trial was ethically problematic because the benefits of birth‑time vaccination are already well established, and the study would expose vulnerable infants to a potentially inferior schedule. The setting in a low‑income nation raised concerns about exploiting a marginalized population for research purposes.

The World Health Organization publicly rebuked the trial’s conduct, and the study has now been placed on hold while the ethical issues are reviewed. The pause reflects growing scrutiny of international clinical research practices that may perpetuate medical inequities.