HIV Research Updates from NIH’s Dr. Carl Dieffenbach at the 10th IAS Conference on HIV Science (IAS 2019)

As the 10th International AIDS Society Conference on HIV Science, or IAS 2019, opened in Mexico City, HIV.gov hosted a Facebook Live session with Carl Dieffenbach, Ph.D., of the National Institutes of Health about initial research presented there and what is in store. Dr. Dieffenbach, Director of the Division of AIDS at NIH’s National Institute of Allergy and Infectious Diseases (NIAID), spoke with his colleague Anne Rancourt. They previewed a topic to be discussed at the conference: what’s new in the HIV prevention landscape, including HIV vaccine research. They also discussed new findings presented on Monday about a potential association between the HIV treatment medication dolutegravir and birth defects.

Here’s additional information on the issues and study findings that Dr. Dieffenbach highlighted:

• HIV vaccine research: Last week, NIH and partners announced plans for a new HIV vaccine study. A Phase 3 efficacy trial, known as Mosaico, will take place at multiple sites in North America, South America, and Europe. The study will assess whether an investigational vaccine regimen designed to induce immune responses against a variety of global HIV strains can safely and effectively prevent HIV acquisition among transgender people and men who have sex with men. Mosaico is a license-enabling study, meaning that safety and efficacy data from the trial could later be used to apply for regulatory approval. Mosaico complements Imbokodo, a study testing a similar vaccine regimen in women that launched in 2017 in five southern African countries. Read more about the Mosaico HIV vaccine trial. Other HIV vaccine developments are being covered in several presentations at IAS 2019Exit Disclaimer this week.
• Other HIV prevention tools: Studies on a variety of non-vaccine HIV prevention tools are being presented at the conference this week. Dr. Dieffenbach summarized the range of HIV prevention modalities currently being studied and underscored the importance of offering individuals a choice of tools that meet their needs. He and Ms. Rancourt also discussed how the U=U (Undetectable equals Untransmittable) message, sometimes also referred to as “treatment as prevention,” is an important part of the HIV prevention toolkit and a cornerstone of ending the HIV epidemic. Dr. Dieffenbach noted, though, that while U=U/treatment as prevention is essential, it alone is not sufficient to end the HIV epidemic. Pre-exposure prophylaxis (PrEP)—a strategy in which HIV-negative people take a daily pill to prevent HIV acquisition—is a highly effective HIV prevention strategy that must be integrated to achieve that goal. Thus, continued research into other HIV prevention modalities remains critically important.
• Safety of dolutegravir at conception: At last year’s International AIDS Conference, preliminary findings from the NIH-funded Tsepamo Study, which conducted surveillance of birth outcomes in Botswana, suggested a greater risk of neural tube defects (serious birth defects of the brain and spine) in infants born to women who were taking the HIV drug dolutegravir at the time of conception. The U.S. Food and Drug Administration, the U.S. Department of Health and Human Services Antiretroviral Guideline Panels, the European Medicines Agency, and PEPFAR issued statements and recommendations regarding the potential risk of neural tube defects to fetuses of women taking dolutegravir at the time of conception. In addition, the World Health Organization (WHO) issued a note of caution about the use of dolutegravir by women of childbearing age as part of its interim guidelines that recommended dolutegravir-based treatment regimens as the preferred first- and second-line antiretroviral therapy for people living with HIV. (Dolutegravir was recommended because it is more effective, easier to take, and has fewer side effects than other HIV drugs.) As a result, some countries paused their plans to make dolutegravir-based HIV treatment regimens their preferred first-line therapy, while others either declined to offer dolutegravir to women of childbearing potential or offered the drug to that population only if women demonstrated they were using effective contraception.

The Tsepamo Study continued as planned in 2018 and 2019 and expanded with NIH funding to gather data on more than twice the number of births as before. Yesterday at IAS 2019, study investigators presented findings from their analysis of more than 119,000 births from August 2014 through March 2019. The analysis indicated that the risk of neural tube defects among infants born to women in Botswana who were taking dolutegravir at the time of conception is less than the initial Tsepamo Study findings suggested. The risk reported yesterday was 0.3%, compared to 0.94% reported last year, relative to a 0.1% risk of neural tube defects found in newborns in the general Botswana population. In addition, the results announced yesterday of two complementary studies of birth outcomes among babies born to women who were taking dolutegravir at the time of conception also indicated a lower risk of neural tube defects than the Tsepamo Study had originally reported. Based on this new evidence and an assessment of the benefits and risks of dolutegravir to the health of both women and the developing fetus, and to help clinicians and national health ministries act on the findings, WHO issued updated HIV treatment guidelines on July 22Exit Disclaimer. Those guidelines reconfirm the recommendation to use dolutegravir-containing regimens as the preferred option for first-line and second-line antiretroviral treatment for all populations, including pregnant women and those of childbearing potential. Read the IAS news release about these studiesExit Disclaimer. View more information about the presentations and access the abstracts of the several studiesExit Disclaimer.

Stay Tuned for More HIV Research Updates

Many of the scientific research advances behind today’s successful HIV treatment regimens and prevention interventions were first presented at conferences such at this. These advances are the foundation of Ending the Epidemic: A Plan for America. To help you stay current on the latest advances, Dr. Dieffenbach and Ms. Rancourt will share additional HIV research highlights from the conference in Facebook Live sessions on HIV.gov on Tuesday, July 23, and Wednesday, July 24. Follow HIV.gov on FacebookExit Disclaimer or TwitterExit Disclaimer for schedule updates and reminders about these events.

About the Conference

The biennial IAS Conference on HIV ScienceExit Disclaimer is the largest open scientific conference on HIV, and this year has assembled more than 5,000 participants from more than 140 countries. This conference presents the latest critical advances in basic, clinical, and operational research that move science into policy and practice. Findings from research supported by the NIH as well as the Centers for Disease Control and Prevention and USAID are among the more than 1,000 abstracts that will be presented.

Read more about Federal HIV research activities and the agencies involved.