CROI 2023: Dr. Dieffenbach Shares Research Highlights on Long-Acting HIV Prevention and Treatment, COVID, and a Cure Update

As the latest research on HIV and other infectious diseases continued to be presented at the 2023 Conference on Retroviruses and Opportunistic Infections (CROI), HIV.gov spoke with Dr. Carl Dieffenbach about some of the highlights. Dr. Dieffenbach is the Director of the Division of AIDS at NIH’s National Institute of Allergy and Infectious Disease. He shared updates about some research on long-acting HIV prevention and treatment and COVID treatment and prevention. He also discussed news of another reported case of HIV cure. Watch our conversationExit Disclaimer with Dr. Dieffenbach below:

Long-Acting HIV Prevention and Treatment

Dr. Dieffenbach highlighted three NIH-supported studies that focused on the effectiveness of long-acting HIV prevention in specific populations and a demonstration of how long-acting HIV treatment can be used to reach people with multiple challenges to treatment adherence. First, he discussed a study presented by Dr. Hyman Scott of the San Francisco Department of Public Health that demonstrated the safety and effectiveness of long-acting injectable cabotegravir (CAB-LA) for HIV pre-exposure prophylaxis (PrEP) among Black men who have sex with men and transgender women who have sex with men, concluding that CAB-LA can be a powerful HIV prevention tool to reduce HIV incidence among these groups that are disproportionately affected by HIV. Next, Dr. Dieffenbach highlighted a study presented by Dr. Sybil Hosek of Stroger Hospital of Cook County that found that CAB-LA for HIV PrEP was found to be safe, tolerable, and acceptable to sexually active adolescent females under the age of 18 in three African countries, where young women and girls are disproportionately affected by HIV.

Finally, Dr. Dieffenbach highlighted a real-world demonstration study by Dr. Monica Gandhi of the University of California San Francisco that found that long-acting antiretroviral treatment (LA-ART) given every four to eight weeks and delivered with comprehensive support services suppressed HIV in people who were previously not virologically suppressed and who experienced housing insecurity, mental illnesses, and substance use disorders. Notably, the study participants included individuals who were on ART but were not virally suppressed and others who were not on ART, which would generally make them ineligible to start LA-ART. Dr. Gandhi reported that all of those participants achieved viral suppression on LA-ART, concluding that LA-ART can be effective for individuals facing challenges to adhering to daily oral ART, particularly when combined with wrap-around services to address challenges such as unstable housing, mental health issues, and/or substance use disorders. Read more about this study.

HIV Cure News

Dr. Dieffenbach addressed news that broke while the conference was taking place about another case of an apparent HIV cure. He briefly discussed the 53-year-old man known as “the Dusseldorf patient” who is in long-term HIV remission nine years after a stem-cell transplant and five years after stopping ART. He is one of a handful of people with both HIV and leukemia who received HIV-resistant stem cells through a bone marrow transplant intended to treat leukemia, a very serious and potentially life-threatening procedure. Dr. Dieffenbach explained that this approach is not one that can be used with all people with HIV because of the very high health risks of a stem cell transplant. But this case does provide researchers with insights into possible paths to a more scalable HIV cure.

COVID Treatment and Prevention

Research on COVID-19 is also being discussed at CROI and Dr. Dieffenbach discussed two studies of interest. The first involved research on the investigational drug ensitrelvir, a protease inhibitor, which demonstrated a significant reduction in the time to resolution of five typical COVID symptoms and was well tolerated. In his presentation of the study findings, Dr. Takeki Uehara of Shionogi & Co. also noted that early analysis suggests that the drug may have an impact on long COVID. Dr. Dieffenbach noted that the NIH-support AIDS Clinical Trials Group is conducting a study, called ACTIV-2dExit Disclaimer, of this once-daily treatment for non-hospitalized adults with early COVID-19 and that the trial is enrolling participants. On the COVID prevention front, Dr. Dieffenbach highlighted a study presented by Dr. Paul Bieniasz of Rockefeller University about his lab’s work to develop monoclonal antibodies against the ACE2 receptor to block COVID entry into human cells. The antibodies are now being evaluated in what Dr. Dieffenbach notes is a promising step since this approach would make it much harder for the SARS-CoV-2 virus to evolve around this form of antibody prevention.

About CROI

CROI is an annual scientific meeting that brings together leading researchers and clinical investigators from around the world to present, discuss, and critique the latest studies that can help accelerate global progress in the response to HIV and AIDS and other infectious diseases, including viral hepatitis, COVID-19, and mpox. More than 3,400 HIV and infectious disease researchers from 72 countries gathered in Seattle and virtually for this forum. Among the studies that are being presented are many that were conducted or supported by NIH, CDC, and other federal agencies. Visit the conference websiteExit Disclaimer for more information; abstracts, session webcasts, and e-posters will be published there for public access in 30 days.

More HIV Research Updates to Follow on HIV.gov

HIV.gov is sharing additional video interviews from CROI 2023 with Dr. Dieffenbach as well as with HRSA’s Dr. Laura Cheever and CDC’s Dr. Jono Mermin and Dr. John Brooks. You can find them on our social media channels and re-capped here on the blog. Be sure to watch, comment, and share!