Early-stage HIV vaccine triggers targeted immune response in human trial

Worldwide, an estimated 40 million people live with HIV. Two-thirds of this group are on the African continent. In 2023, more than 600,000 people died from HIV-related causes and 1.32 million were infected. There is no vaccine against the world’s second most deadly infection, after TB. However, researchers from Amsterdam UMC have set an important first step in reaching that goal. The results of their phase one trial are published in Science.

“In short, for a preventative HIV-vaccine to work, it should induce broadly neutralizing antibodies against all the diverse strains of the virus. We’ve seen that those who have been infected with HIV have been able to develop these antibodies but it’s incredibly challenging to trigger the body to produce these antibodies with a vaccination,” says Tom Caniels, postdoctoral researcher at Amsterdam UMC and first author of the study.

Together with partners from Rockefeller University, and ten other American partners, the Amsterdam-based research team set out to trigger this response by developing a vaccine that uses specifically engineered immunogens, known as germline-targeting.

After developing this in the lab, the team built a vaccine that gave participants a dose of the Env trimer GT1.1; a priming immunogen that should trigger the body’s antibody response. Forty-seven participants in the trial received either a high dose, a low dose or a placebo.

“Across the participants, we saw an immune response that indicates that we’re on the right track. We saw that we can target the cells that we need to target with atomic precision. The next step is to further stimulate these cells to secrete broadly neutralizing antibodies,” says Rogier Sanders, Professor of Virology at Amsterdam UMC and last author of the study.

If the team can reach their next goal, it would continue their work to ultimately create a vaccine for HIV. This is something that Sanders and his team have been working on since the turn of the millennium.

Global context

This finding comes at a time when many studies like this one are facing uncertain futures. Constance Schultsz, Professor of Global Health and Head of Amsterdam UMC’s Global Health department, believes that findings like this one should be celebrated:

“This positive outcome is an important step and is the result of the combined ingenuity and perseverance of international researchers over many years. It is a success we absolutely need to celebrate in a time in which global health, particularly in relation to HIV, is affected in many ways.

“We should make sure and work together that the follow-up studies on this vaccine can move on as planned considering their potential global impact, if proven successful,” she says.

More information: Tom G. Caniels et al, Precise targeting of HIV broadly neutralizing antibody precursors in humans, Science (2025). DOI: 10.1126/science.adv5572

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