A US-backed hepatitis B vaccine trial involving newborns in Guinea-Bissau, which had drawn significant global criticism, has been officially halted, according to the lead researcher. Frederik Schaltz-Buchholzer, a Danish researcher involved in the project, announced on LinkedIn that the study "will not move forward in Guinea-Bissau" because "we were not given the necessary governmental approval."

The proposed trial was set to be funded with $1.6 million from the US Centers for Disease Control and Prevention (CDC), alongside an equal amount from private entities including the Bill Ackman-backed Pershing Square Foundation and the Bluebell Foundation. This funding structure and the nature of the research had ignited a firestorm of ethical debate.

Previously, the Minister of Health for Guinea-Bissau, Quinhin Nantote, had publicly denied that the study would proceed, stating, "This is not even remotely true." The vaccines intended for the trial are now under the control of the Guinea-Bissau government, having been apprehended by authorities during a search of the Bandim Health Project offices.

Experts like Paul Offit, a vaccines specialist at the Children’s Hospital of Philadelphia, had sharply criticized the proposed study, deeming it unethical. Offit, however, also emphasized the importance of vaccinating children, stating, "The solution is clear here: take the money and vaccinate as many kids as you can." He suggested that Guinea-Bissau should prioritize rolling out immunizations to all newborns as soon as possible, noting the country's current plan to offer the universal birth dose in 2028.

The research, led by Danish scientists Schaltz-Buchholzer, Christine Stabell Benn, and Peter Aaby, aimed to explore a hypothesis that live vaccines, such as Bacillus Calmette-Guérin (BCG), might offer broader mortality benefits beyond their specific disease prevention. The researchers were investigating whether administering another vaccine, like hepatitis B, concurrently could potentially diminish these hypothesized non-specific effects.

Critics argued that the trial's design and its focus on potential non-specific effects, rather than solely on the direct prevention of hepatitis B, raised serious ethical questions, particularly in a population with high infant mortality rates. Concerns were voiced about the allocation of resources and the potential for exposing vulnerable infants to risks without clear, direct benefits that outweighed those risks.

The halt to the trial signifies a victory for advocacy groups and ethicists who had called for its termination. It also highlights the complex interplay between international health initiatives, governmental oversight, and ethical considerations in global health research.

Moving forward, the focus is expected to shift to how the secured vaccines can be utilized for public health programs in Guinea-Bissau, potentially accelerating the country's timeline for universal hepatitis B vaccination among newborns.