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The need for collaboration and community-inclusive practices to advance HIV prevention efforts in the face of significant funding constraints was a focal point of those who spoke during a session at the International AIDS Society meeting in Kigali, Rwanda.

The session, co-hosted by the Bill & Melinda Gates Foundation, Gilead, Merck, and the Reproductive Health Institute, gathered researchers, advocates and community leaders to address adapting to a changing funding environment for research of HIV prevention. They addressed the evolving landscape of HIV prevention, including oral HIV preexposure prophylaxis (PrEP), HIV vaccines and broadly neutralizing antibodies (bnAbs), a newer area of research.

They urged attendees of the need to continue with research of HIV prevention despite funding from the United States that is being pulled back. A concern of speakers was the recent termination of 191 HIV-specific grants by the U.S. National Institutes of Health (NIH), which slashed more than $200 million in funding — disrupting early-stage research, behavioral interventions, and vaccine development.

“We saw that $99 million was cut from HIV prevention, including the work that I do in HIV, biomedical products, behavioral interventions and access barriers and key populations were not spared,” Nyaradzo Mavis Mgodi, MB.ChB., biomedical HIV prevention methods, University of Zimbabwe Clinical Trials Research Centre, said during the session. “The cuts have adversely affected us all.”

Mgodi and other speakers presented key takeaways from the Future of HIV Prevention Clinical Trials Summit, which was held in June 2025 in Johannesburg, South Africa. At the heart of the discussions at the June Summit and at IAS was the urgent push for smarter, more agile clinical trials that keep the focus on community engagement. Speakers stressed the need for innovative trial designs that use modeling and artificial intelligence that can accelerate development without sacrificing inclusivity or scientific rigor.

Speakers also talked about the HIV prevention pipeline and recent results of trials. Despite the recent approval of lenacapavir as a twice-yearly PrEP, there is still a need for choice in HIV prevention. Developed by Gilead Sciences, lenacapavir (now with the brand name Yeztugo) was approved by the FDA on June 18 as both an oral tablet and as a subcutaneous injection.

“The context for HIV prevention research is rapidly evolving,” Grace Kumwenda, regional program manager at AVAC in Malawi, said during the session. “We are facing shifting epidemiology. Some populations are seeing lower incidence, and others remain quite underserved. At the same time, how do we design and prioritize research?”

Oral PrEP

Merck recently announced that it will begin phase 3 clinical trials of MK-8527, an investigational once-monthly oral for HIV PrEP. The EXPrESSIVE-11 trial will evaluate the safety and efficacy of MK-8527 in 16 countries and will begin enrolling in August 2025.

MK-8527 is a nucleoside reverse transcriptase translocation inhibitor (NRTTI), and in the trial it will be compared with emtricitabine/tenofovir disoproxil fumarate, which is available as a generic. A branded emtricitabine/tenofovir disoproxil fumarate is marketed as Truvada by Gilead.

A phase 2 trial of MK-8527 enrolled 350 participants with a low likelihood of HIV-1 exposure, who were randomized to one of three doses of MK-8527 or placebo once monthly for six months. In the trial, the rates of adverse events were similar among those in the MK-8527 arms and those in the placebo arm, and no clinically meaningful changes were seen in laboratory tests, including total lymphocyte and CD4 T-cell counts.

Rebeca Plank, M.D., senior principal scientist, clinical research at Merck, said during the IAS session that researchers carefully considered the comparator that would be used in EXPrESSIVE-11 trial, consulting community organizations and other stakeholders.

Originally, researchers considered using Vocabria (cabotegravir), an oral integrase strand transfer inhibitor (INST) that is taken daily when used as PrEP. But MK-8527 will be used monthly, and Plank said researchers were looking for direct comparison.

“This was done in consultation with various stakeholders from the beginning and even before the protocols really began to be drafted,” Plank said.

She also pointed out that the comparator was chosen before the approval of lenacapavir, a twice-yearly PrEP. Developed by Gilead Sciences, lenacapavir (now with the brand name Yeztugo) was approved by the FDA on June 18 as both an oral tablet and as a subcutaneous injection.

Vaccines

Despite many years of research, a vaccine using active immunization hasn’t been successfully developed because of biological and technical challenges of making an HIV vaccine. Mgodi said there have been some positive signals, especially with RV144. A Thailand study of RV144 conducted almost a decade ago demonstrated that the vaccine was safe and had a statistically significant decrease in HIV infection. But protective immunity appeared to wane, and the vaccine is not currently available.

Other studies have given a negative result because HIV is highly unstable.

Some, however, have questioned whether a vaccine is still needed because of the availability of long-acting PrEP such as lenacapavir. Mgodi made the case during her presentation that vaccines would add to the arsenal of HIV prevention.

“There are people who are not adherent to PrEP, and we know that many people who acquire HIV don’t perceive themselves to be at risk,” she said. “That’s one reason why we need a vaccine as an alternative to PrEP that is focused on specific populations, which really sometimes marginalizes others or stigmatizes others.”

She said that vaccines have the potential to prevent between 8.4 million and 19 million new HIV infections, depending on efficacy.

bnAbs

Research is continuing, however, on passive immunization with broadly neutralizing antibodies, or bnAbs, which are a type of antibody that can recognize and block different HIV strains. Organizations, such as IAVI, and groups funded by the National Institutes of Health (NIH), such as the Scripps Consortium for HIV/AIDS Vaccine Development (CHAVD), are conducting research in this area.

In May 2025, IAVI and Scripps Research released data from two separate phase 1 trials showing that a targeted vaccine strategy can successfully activate early immune responses relevant to HIV. The trials included nearly 80 participants from both North America and Africa, and the study was published in Science on May 15, 2025.

One of the trials tested a stepwise vaccination strategy, in which a priming dose and a distinct booster dose were given sequentially to guide the immune system through stages of antibody development. The second trial focused on the priming stage and showed that an initial vaccine dose could successfully activate the desired immune cells in African participants.

Commercial companies, such as ViiV Healthcare, are also developing bnAbs. In March 2025, ViiV released data from a phase 2b study that N6LS, a bNAb administered every four months, effectively maintained undetectable viral load when combined with Apretude, a long-acting cabotegravir. The study found that the combination kept viral levels suppressed in adults living with HIV who were already stable on treatment. It was also well tolerated by participants.

July 14 (UPI) — A new study of more than 1.2 million people found no link between aluminum in childhood vaccines and long-term health problems, including autism, asthma or autoimmune diseases.

The research, published Monday in the Annals of Internal Medicine, looked at 50 chronic conditions.

They included 36 autoimmune diseases, nine types of allergies and asthma, and five neurodevelopmental disorders, such as autism and ADHD, NBC News reported.

Aluminum has long been added to vaccines to help the body build a stronger immune response. But the additive has also become a target for vaccine skeptics, including some public figures who have called it harmful.

“Our study addresses many of these concerns and provides clear and robust evidence for the safety of childhood vaccines,” senior author Anders Hviid, head of epidemiology research at Statens Serum Institute in Denmark, said.

“This is evidence that parents need to make the best choices for the health of their children,” he added.

His team used health records from Denmark’s national registry to study people born between 1997 and 2018. They were followed through the end of 2020.

Because health data in Denmark is carefully tracked, the team was able to compare kids who received more aluminum in their vaccines before age 2 with those who received less. Unvaccinated children were not part of the study, NBC News said.

Ross Kedl, a vaccine expert at the University of Colorado Anschutz Medical Campus who reviewed the findings, said this type of large-scale research is only possible in countries like Denmark.

“[This excellence is] partly because they have, for a long time, had such a unified health system,” Kedl told NBC News. “Everyone is tracked for life from birth and you can go back for many years and ask, ‘Can we find a link between something that happened in the past and in the future?’ “

The study was, in part, a response to a 2022 U.S. Centers for Disease Control and Prevention-funded study that had suggested a link between aluminum-containing vaccines and asthma. That study has been widely criticized since.

Experts said it failed to distinguish aluminum in vaccines from aluminum from other sources, such as food, water, air and even breast milk.

“Aluminum is part of our daily diet and has been since the beginning of time. That is the point people don’t understand,” Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, told NBC News.

Dr. Paul Offit, director of the Vaccine Education Center at Children’s Hospital of Philadelphia, said the earlier study didn’t properly account for outside factors.

“If you are looking at people who got vaccines that contained aluminum versus those who had fewer, you have to control for confounding factors, you need to know that the only different source of aluminum these people received was from those vaccines,” Offit said.

Aluminum is used in some vaccines as an adjuvant – a substance that helps trigger a stronger immune response.

“An adjuvant is a substance that alerts the body’s immune response to the vaccine’s antigen,” Kedl explained. “Without adjuvants, you actually create tolerance, which is the opposite effect of what you want a vaccine to do.”

In the U.S., aluminum salts are used in vaccines for diphtheria, tetanus and pertussis (DTaP), as well as for HPV, hepatitis B and pneumonia.

“The aluminum that is in vaccines is in the form of extremely small amounts of aluminum salts, which is not the same as elemental aluminum which is a metal,” Hviid said. “It’s really important for parents to understand that we are not injecting metal into children.”

Most of the aluminum leaves the body within two weeks, but trace amounts can stay for years.

Experts say no single study can prove something is safe, but this new research adds to years of research showing that aluminum in vaccines is not harmful.

“One study does not make for a safe vaccine supply or not,” Osterholm said. “It’s the accumulative data that comes from many studies that have been done, that together demonstrate the safety of vaccines.”

Hviid, meanwhile, pointed out that vaccines containing aluminum are “the backbone” of childhood immuniation programs.

“It is critically important that we keep politics and science apart in this issue,” he said. “If not, it is the children, including U.S. children, who are going to suffer the consequences.”

More information

Children’s Hospital of Philadelphia has more on aluminum in vaccines.

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