October 9, 2024
The data and discussions at HIVR4P 2024 in Lima, Peru, so far this week have been setting the stage for understanding what’s been accomplished in HIV prevention, how far the field remains from reaching targets, understanding how choice works and why it matters, and where the research agenda is headed. But, as AVAC’s Mitchell Warren told Axios, “lenacapavir is on everybody’s lips here at HIVR4P 2024. That’s probably the second-most popular word this week; I think the most popular word is access.”
Read on for highlights!
Access and Choice: Inextricably linked
Results of the PURPOSE 2 trial of injectable lenacapavir (LEN) for PrEP were presented to a packed room of conference attendees reflecting the magnitude of what a twice per year injectable that works across populations could mean for HIV prevention. Co-chaired by leading researcher and IAS President Beatriz Grinsztejn and leading advocate and Choice Agenda moderator Jim Pickett, the session began with Pickett’s clarion call for accelerating equitable access—for everyone, everywhere.
PURPOSE 2 investigator, Colleen Kelley of Emory University, presented initial safety, efficacy and demographic data and reiterated that only two HIV acquisitions occurred among the 2,179 trial participants receiving LEN injections twice per year – resulting in a 96% reduction in risk compared to the estimated background incidence and an 89% reduction compared to individuals taking daily oral F/TDF. See AVAC’s updated Lens on LEN and the new Plan for accelerating access to LEN.
While these data have captured global interest and attention since the announcement of the PURPOSE 1 results in June, advocates have made it clear that more choices are needed to translate options and access into impact! In addition to PURPOSE 2 results, the session, Novel Antiretrovirals and Formulations for Prevention, featured several presentations focused on other kinds of new HIV prevention options in the research and development phase that, should they make it to market, would be new and innovative ways for more people to protect themselves from HIV.
Two researchers, Renee Heffron and Raphy Landovitz presented data on a now shut-down program of a once-a-month oral islatravir (ISL) PrEP option. Landovitz and Heffron presented long-awaited safety data from IMPOWER-22 and IMPOWER-24, the sibling efficacy studies of ISL in cisgender women, MSM and transgender women that were halted in late 2021, and ultimately discontinued. Data showed that ISL was well-tolerated, but importantly, that the effect on lowering T-cell lymphocytes, for which the program was stopped, did return to normal in the 18-month follow-up period after participants were taken off ISL. This information is helping inform the ongoing development program of Merck’s next-generation monthly oral PrEP option MK-8527, now in a Phase 2 trial, with a possible Phase 3 efficacy trial slated to begin next year.
Research was also presented on the acceptability of an on-demand, single-dose tenofovir rectal douche in a small number of young men who have sex with men of which 80% found it preferable to daily oral PrEP to use as needed before participating in receptive anal sex. While research continues on its efficacy as a PrEP option, the study presented by Renata Arrington-Sanders suggests a rectal douche may also be a desirable tool for some populations.
Others presented on a new long-acting biodegradable hydrogel injectable system for single or multi-purpose prevention of HIV and/or pregnancy (currently in animal studies) and a study proving that most people maintained viral suppression if switched from a 3-drug ARV regimen to a 2-drug regimen.
At the session Manifest Choice: Enabling a future free of HIV presenters described the diverse needs and complex challenges of different populations. “We all know that there’s never going to be a miracle drug or a miracle intervention, but in navigating how we manifest choice, we really need to keep our eye on choice as a priority and ensure decision makers in this process don’t get laser-focused on one product. We must continue to drive a nuanced advocacy agenda for a range of options,” said AVAC’s Stacey Hannah.
The African Women Prevention Community Accountability Board’s (AWPCAB) HIV Prevention Choice Manifesto provides an advocacy tool for increasing political and financial support for integrating every proven method of HIV prevention into the HIV response. “We’re at a historic turning point—but only if countries and funders listen to evidence-based calls for programs that prioritize choice, not just individual products,” said veteran advocate Yvette Raphael.
“We need to be grounded in a human rights approach; people have the RIGHT to choose,” these words brought a thunderous applause during the session, Prevention Product Profiles for Future Options, Including Long-acting PrEP Formulations and Products from Laio Magno of Universidade do Estado da Bahia in Brazil.
Magno discussed key insights from the PrEP1519 study out of Brazil where researchers looked at a key population at risk for HIV, young adolescents. Adherence and lack of awareness of PrEP options, including the recently approved long-acting injectable cabotegravir, were major challenges, the study found. Making participants aware and providing them with a “playlist” of approved PrEP options (daily oral, event-driven and long-acting injectable), supports them to make choices that fit in their lives.
The Future of Vaccines
Exciting new insights are informing early phase vaccine research, as the field builds on lessons learned from large phase trials that all ended without efficacy in recent years. The session, HIV Vaccines: The Quest Continues, made the case for the essential role of HIV vaccines. With approximately 40% of new cases arising among populations that would not be defined as at risk for HIV exposure, said the HVTN’s Larry Corey. That means population coverage of PrEP or PEP would need to be unrealistically high—200 people on PrEP and PEP to prevent one case among populations at low risk of HIV. In the history of infectious disease, “there’s only one way we’ve ever done that [reached such high coverage] and that’s through a vaccine. If we really want to achieve what we need to do in HIV, it’s going to be a vaccine,” said Corey.
At the session, Quo vadis: Future design and conduct of vaccine and bNAb clinical trials, AVAC’s Grace Kumwenda agreed and reminded attendees that despite progress in early-phase bNAb and vaccine development (and many challenges), and a late-stage toolbox of highly effective prevention options including new long-acting PrEP, the world continues to see high HIV incidence. Strategies toward an HIV vaccine are part of the upstream pipeline that must continue to be supported. The newly released People’s Research Agenda (PRA) shares a clear, concise and collaboratively developed set of priorities for how prevention research should be conducted and what products should be developed. “There are several questions that have been raised through community engagement [in developing the PRA]. We are asking ourselves about target product profiles, what are ideal characteristics of a vaccine, of an antibody combination? How do we conduct future HIV vaccine trials, and what is the right comparator for that? These are vital considerations,” said Kumwenda. The NIH’s Jeanne Marazzo added her voice of support for the PRA, calling it a manifesto.
PrEP Around the World
Global PrEP uptake may be up, but it’s nowhere near where we need to be. At the session, The Big Picture: Global trends in HIV prevention, AVAC’s Catherine Verde Hashim discussed data on PrEP typologies across the world. Findings demonstrate that countries with strong PEPFAR support and/or who have led on approvals of PrEP options saw greater distribution and volume of PrEP. Another study, presented by Ribhav Gupta from the University of Minnesota Medical School, found an overall decline in HIV incidence in certain US municipalities that was correlated to Ending the Epidemic (EHE) programming. But data also showed some increase since 2019. These new cases could be connected to rising HIV/STI prevalence and decreased testing during the COVID-19 pandemic. As Carlos Toledo from the US CDC stated during discussion, “initiations are just a starting point and doesn’t say anything about impact.”
GPP: From clinical trials to the research agenda for prevention at large
“GPP is often thought of as a tool for conducting clinical trials, and it very much is that, and that’s very much how it was developed, but it is also about ensuring that broader research agendas move forward with the community’s heart at its core. And that communities and other stakeholders are able to hold the research process accountable for doing that,” said AVAC’s Stacey Hannah at the session Advancing Good Participatory Practices (GPP) in Research: Enhancing Community Engagement for Impact, co-hosted by AVAC and Wits RHI, as part of the Coalition to Accelerate and Support Prevention Research (CASPR). Three case studies covered strategies for meaningful engagement and discussed the challenges of GPP implementation—it looks different in every context, outcomes can be difficult to quantify, engagement work must overcome being seen as secondary to clinical processes, and engagement risks being undervalued and under-resourced. See AVAC’s GPP Body of Evidence, an important resource that brings together a set of tools highlighting the value of GPP, as well as the nuts and bolts of how to get it done.
Rising to the Challenge
As NIAID Director Jeanne Marrazzo helped open the meeting providing a snapshot of the global epidemic, which is still far from reaching global targets for controlling the epidemic, even with highly efficacious products now approved, she pointed to regions where incidence is on the rise and to emerging threats from global conflicts, which further drag down progress. “For these reasons, we cannot rest. We have to remember that people need more choices! Sexual encounters may be infrequent, not planned, or not consensual—it cannot be said enough.”
Lima to date is a whirlwind of passion, a sobering confrontation with the work that remains to be done, but most of all it is an inspiration, because the interventions moving forward hold great promise and because the advocacy tracking it all is demanding that the field rise to the challenge.