For nearly 15 years, Dennis Burton worked on a project aimed at solving what he calls "one of the most difficult problems in biomedicine" — creating an HIV vaccine.
That work was funded by the largest National Institutes of Health-funded program devoted to such research, with a seven-year grant totaling $258 million, and is considered one of the leading vaccine efforts. On May 30, he learned that work will end. In a video call, NIH officials told him that the Trump administration was terminating the program next year.
"It's just devastating. So much human toil has gone into this," says the Scripps Research Institute immunologist. "Just when it looked like we could beat this virus, we're going to give up."
Designing an effective HIV vaccine has proven immensely challenging for researchers, who've spent decades working to figure out how to prompt the immune system to protect against this wily virus, says Burton.
One of the reasons it's so difficult is because the HIV virus evolves faster than any other known virus. Even within an infected individual, the virus can splinter off into many new variants, effectively dodging the immune system's first-responders — antibodies.
Burton and his colleagues at the Center for HIV/AIDS Vaccine Development — a consortia of researchers at Scripps and Duke University known as CHAVD — have been working on a promising approach aimed at coaxing the immune system to make "broadly neutralizing antibodies" capable of attacking many forms of the virus. Clinical trials were slated to start as soon as next year. Without funding, they won't proceed.
"Complex and duplicative health programs have resulted in serious duplication of efforts that dilute taxpayer resources," a Department of Health and Human Services spokesperson told NPR in response to a question about the rationale behind the cuts.
The news of the termination comes as the HIV vaccine has largely coalesced around the idea that broadly neutralizing antibodies are central to an effective HIV vaccine, says Mark Feinberg, president and CEO of IAVI, a non-profit that develops vaccines. Scripps and Duke researchers were pursuing different approaches toward that shared goal, which is good, he says. "You don't know which is going to work and whether there's potential synergies between the two approaches."
The Trump administration's termination of CHAVD is just the latest in a string of cuts and cancellations of HIV-vaccine related grants, from clinical trials to basic laboratory research. In 2022, the U.S. accounted for nearly 90% of the $731 million devoted to HIV vaccine research globally. If those funds dry up, many researchers fear that the prospects of getting an effective HIV vaccine will dwindle.
"After many years of frustration and negative results we now believe that there is a pathway to develop an efficacious HIV vaccine," says Feinberg. "It's really disappointing at this time to have the foundation kicked out from underneath you."
A canceled African trial
The NIH-funded project isn't the only vaccine research being affected by the Trump administration.
In late January, biomedical scientist Linda-Gail Bekker and her colleagues were gathered in Tanzania to discuss their efforts to develop and test HIV vaccines across eight African countries. That team, called The BRILLIANT HIV vaccine consortium had won a five-year $45 million dollar grant from USAID in 2023 and was days away from starting its first clinical trial in humans when it got a stop-work order from the U.S. government.
"To say we were disappointed is to completely underplay how we felt," said Bekker, of the University of Cape Town. "We felt desperate, that something we'd been working so hard to accomplish was removed without a good reason."
Bekker and her colleagues had spent a year assembling a team of research biologists and clinicians from around the world to develop immunogens — substances that kick start an immune response that serve as the basis for future vaccines. They looked for inspiration, in part, from HIV patients in South Africa whose bodies seem to naturally produce broadly neutralizing antibodies.
"The idea was to base [vaccines] on [HIV] viruses that had been discovered in Africa and immunogens designed based on those viruses as templates," she said. Underscoring the global nature of HIV vaccine research, scientists with the CHAVD program helped design some of the immunogens, Bekker says.
Then, the team would "put these immunogens into humans, in clinical trials, to test whether we can actually move the human immune system to make broadly neutralizing antibodies," says Bekker. Those clinical trials were slated to happen in African countries where the HIV epidemic is most severe, allowing researchers to more clearly assess whether the vaccines work than if they were to test them in, say, the U.S.
Now, Bekker and her colleagues have largely stopped vaccine-related work and are instead scrambling to find alternative funds for the project.
The USAID grant is "irreplaceable" in terms of its scope, says Bekker. The team is now figuring out how to scale back their ambitions by running fewer, smaller clinical trials. But that means the data will be less valuable, says Bekker.
These kinds of international collaborations are commonplace in efforts to develop and test HIV vaccines, researchers told NPR — and face an uncertain future under the Trump administration.
In May, NIH announced it would no longer fund foreign "subawards," which allow U.S. scientists to pay foreign collaborators to conduct research overseas. Last year, NIH funded more than 3,600 such awards. Instead, foreign researchers must apply directly to NIH for funding, a barrier that will likely reduce foreign collaboration, says Susan Zolla-Pazner, a microbiologist at the Ichan School of Medicine at Mount Sinai.
"Foreign partners in HIV research are extremely important," she says. "It's a global disease and viruses don't recognize national boundaries." For example, if a researcher wanted to study how to prevent babies from being infected by their HIV-positive mothers, the best thing to do is conduct the study in a place where such mothers exist in sufficient numbers, which is outside of the U.S. says Zolla-Pazner. If you can't do that, "it's more than a hurdle. It's a brick wall in terms of being able to understand how to protect a population of women and their children."
On top of these restrictions, researchers worry generally about the prospect of getting vaccine-related grants accepted in the current climate. NIH has already cancelled or delayed payments on over 2,500 individual grants, including some related to HIV vaccine research, and under the Trump administration has signaled a shift away from mRNA vaccine research — the same platform that allowed rapid development of the first COVID-19 vaccines.
Pessimism — and yet hope
Altogether, the administration's actions — and pledges to cut funding for NIH grants by more than 40% next year — have many researchers pessimistic about the prospects of developing an HIV vaccine anytime soon.
"My personal view is that advances will stall out," says Burton, the Scripps scientist. "The United States led the world in HIV vaccine research, I don't think that anyone's going to step into the breach," he says. "Philanthropy can certainly help, but they're unlikely to step in with the magnitude of funding needed."
Even if funding eventually comes back, from the U.S. or elsewhere, it can be difficult for research groups to bounce back from extended cuts.
"It is putting a period in the middle of a sentence," says Zolla-Pazner. "You cannot reconstitute that group, even two months later, because people have lost their jobs."
Other researchers are hopeful the field will eventually build on the progress already made to deliver an HIV vaccine.
"It remains a huge challenge, but we now have little chinks of light of how to move this field forward," says Bekker. "I believe we will get back on track, but we will have lost time," she says. "And that means people's lives."
Have information you want to share about the ongoing changes at federal science agencies and their effects on research? Reach out to Jonathan Lambert via encrypted communications on Signal: @jonlambert.12
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