The global advocacy for HIV/AIDS has been a model of success for an array of initiatives such as the climate protection movement. Analysts point to the multi-stakeholder composition and the autonomy from governments as some of the features that have allowed for an increasing global consensus on the necessary steps toward scaling up HIV treatment and prevention. But another reason why the global advocacy for HIV/AIDS has had success is the periodical input it receives from academic and technical forums such as the International AIDS Society (IAS) Conference on HIV Science, where scientific innovations are discussed and used to inform science-based policies.
The 9th IAS Conference on HIV Science took place in Paris from July 23-26, 2017 and provided people living with and affected by HIV with new findings from research studies and clinical trials that promise to revolutionize the HIV landscape. Though many studies were presented at the conference, we would like to highlight those studies related to the development of long-acting agents, which are innovative therapies for treating and preventing HIV infection that are under development and do not require daily pill taking. Because the effectiveness of antiretroviral therapy (ART) for HIV treatment and prevention is contingent on adhering to specified regimens, long-acting agents have the potential to make HIV treatment and prevention even more effective.
The Paris Statement released in conjunction with the IAS Conference stresses the need to “prioritize the development of antiretroviral (ARV) formulations that support long-term adherence and reduce the risk of viral resistance.” In this regard, the Paris Statement notes that “[d]evelopment efforts must include nano, injectable and other long-acting formulations.”
Focusing on HIV treatment, one notable finding related to long-acting agents that was released at the IAS Conference includes the positive results of a weekly oral therapy, where a single low dose of the novel drug MK-8591 (also known as EFdA) was associated with a rapid and robust reduction in HIV viral load. However, the landmark study was the LATTE-2 study about long-acting injections of cabotegravir/rilpivirine. Through 96 weeks, a larger number of patients who were assigned to this every-4-week or every-8-week dosing therapy (87% and 94% respectively) maintained viral suppression as compared to patients who stayed under a daily three-drug oral regimen (84%). As long-acting ARV injections are evaluated in phase 3 clinical studies, findings from these studies are anxiously awaited.
Now turning to HIV prevention, researchers also presented findings related to long-acting injectable drugs for pre-exposure prophylaxis (PrEP). Important results were released regarding the HIV Prevention Trials Network (HPTN) 077 study, which sought to prove the safety, tolerability and pharmacokinetics of injectable cabotegravir in low-risk HIV negative men and women. It is remarkable that participants assigned to injections every 8 weeks (with the first two doses administered every 4 weeks) showed appropriate levels of medicines in their blood and high tolerance. These findings support the dosing frequency used in HPTN 083 and HPTN 084, two ongoing studies that will test the efficacy of long-acting cabotegravir for PrEP in two at-risk groups: cisgender men and transgender women who have sex with (HPTN 083) and women in sub-Saharan Africa (HPTN 084). On another note, MK-8591 (the novel weekly-dosing regimen tested for HIV treatment) showed promising results in a prevention study with macaques. All this suggests that long-acting ARV formulations that are effective for HIV treatment could work as well for HIV prevention.
Research to come up with new drugs and regimens for maintaining viral suppression and improving the lives of people living with and at risk for HIV represents a main contribution of the 9th IAS Conference to the advancement of HIV science. To prepare the policy community for long-acting agents for HIV treatment and prevention, the O’Neill Institute has established a project to explore a range of issues related to United States health system adoption and community acceptance of these agents if research ultimately demonstrates that they are safe and effective. Check out our webpage for future updates on this project.
This blog post was co-authored by Javier Saladich, a Summer Research Intern at the O’Neill Institute. Javier is a third-year law student at ESADE Business and Law School in Barcelona, Spain.