The CDC’s non-human primate research program has filled a crucial space between basic lab research and human trials in HIV
The U.S. Centers for Disease Control and Prevention (CDC) has instructed staffers to end research using non-human primates by the end of the year, according to a report in Science, a decision that science advocates say could seriously hurt significant ongoing and future studies on HIV prevention and treatment and cure research. The mandate affects 200 macaques living at the CDC’s headquarters in Atlanta who have been used to study HIV, hepatitis and other infectious diseases.
The fate of the animals is uncertain. The U.S. Department of Health and Human Services (HHS) did not respond to questions from POSITIVELY AWARE, though it does have a road map for reducing testing on animals, which includes new methodologies such as organ-on-a-chip systems and computational modeling, but no details on what to do with non-human primates currently being used.
According to Science and confirmed by Bloomberg News the CDC’s order was shared by a former DOGE employee, Sam Beyda, who was recently named CDC’s deputy chief of staff within HHS despite having no background in science.
Although the decision does not affect other research using non-human primates in the U.S., primarily at universities, the termination of the CDC’s non-human primate research program will be a blow to HIV studies, especially in ongoing research in long-acting PrEP for HIV, as well as vaginal microbicides to prevent HIV in women.
Though small, the CDC’s non-human primate (NHP) research program has filled a crucial space between basic lab research and human trials in HIV, according to Deborah Fuller, director of the Washington National Primate Research Center.
“This was not just exploratory,” Fuller told POSITIVELY AWARE. “This had advanced to the point where the non-human primate studies were being done as pre-clinical research prior to going in human trials. It had been going on for decades [with] millions of dollars invested and they’re at the finish line here, and it’s gotten cut off at the knees.”
Fuller emphasized that NHP research plays a small part—about 1%—of all animal research, but is essential to advancing science, and is without alternatives in the area of HIV. “Non-human primates are the closest model to human,” Fuller said. “When we’ve exhausted all other methods for addressing a question, the non-human primate plays a critical role in helping [with] that last step before we go into clinical trials to validate if something’s going to work, and that it has [a] high likelihood of being safe. Folks thinking that we can expect breakthroughs in biomedical research without non-human primates have another thing coming.”
Fuller said she’s concerned that the CDC’s decision might be the start of a larger-scale government moratorium on NHP research, which could affect all of the nearly 7,000 non-human primates that the NIH oversees. And that this could have a domino effect on research in academic institutions with NHP studies.
“The implications for [this decision] can make detractors think that they can go after other NHP research programs, and that’s a potential concern.”
Without clarification from the federal government, it’s difficult to speculate on whether ending NHP research was about benefitting the animals, although groups like the White Coat Waste Project, an advocacy group pushing for the end to animal research, are taking the decision as a win.
But Mitchell Warren, executive director of the HIV advocacy group AVAC, suggested that the NHP model has saved human lives that might not have otherwise been saved.
“In some diseases, you give people a drug, and then you challenge their immune system with a virus, but we only do that with pathogens where we know we can completely treat and cure someone,” Warren said.
“In a human, it would be unethical to expose them to HIV intentionally and see if the drug prevents them from getting HIV. But the [NHP] model allowed the CDC to do these challenge models where the macaques were given tenofovir [a now commonly used HIV drug that’s a cornerstone of many treatments], they go through a rigorous challenge model of HIV, and they found that the vast majority of the macaques didn’t get HIV. That evidence is safeguarding as well, and that led to the development of the human clinical trials that have shown tenofovir prevents HIV, that the dapivirine vaginal ring prevents HIV, that cabotegravir prevents HIV (as a PrEP drug, cabotegravir is branded as Apretude; cabotegravir is also the key drug in Cabenuva, the long acting injectable for HIV treatment), and that lenacapavir prevents HIV (as long-acting injectable PrEP, lenacapavir is marketed under the brand name Yeztugo; as a long-acting injectable component of treatment for highly-treatment-experienced people with HIV, lencapavir is marketed as Sunlenca). So if it had not been had not been early non-human primate research at the CDC, it is safe to say we wouldn’t have PrEP at all, or certainly not as soon as we now have it sitting here in 2025 with this range of methods.”
Warren believes that groups against animal testing have a “legitimate concern” and that there should be protections for the animals. “But if there are alternatives [to using NHPs] in HIV research I’m not aware of them.”
Warren added that he doubts the CDC’s decision is based on ethical treatment of animals, however, and more likely to be about money. Earlier this year the U.S. House of Representatives budget bill zeroed out funding for the CDC’s Division of HIV Prevention. If so, he said, that would be “incredibly short sighted.”
“This body of work costs money but it pays dividends on investment. The investment in the CDCs work here has paid off many times over in terms of drug discovery. I acknowledge that budgets will be trimmed and some things are going to get cut, [but] I would regard this body of work as essential as core business. I think it’s randomly naïve to think that this is not going to have repercussions in longer-term scientific research and development.”
At the University of Washington, where Fuller works, the slashing of government funding, including the shutdown of UNAIDS, had already decimated research into new microbicide treatments to protect women from HIV, even before the mandate to end NHP research. Other HIV programs, including research for HIV cure and HIV vaccines, are still active and funded, for now.
Still, Fuller expressed concern that the federal government might be eyeing all “wet lab” basic research—studies involving cells and cultures, versus “dry lab” computer modeling—for termination.
“From what I've seen, and this is just speculating, it seems that the vision of what the CDC does under the new administration may be changing,” she said. “A lot of the wet lab basic research programs seem to be going away, and [non-human primate research] is a high visibility one.”