HIV Vaccine Research Update with Dr. Dieffenbach from CROI 2023

NIAID Now | February 24, 2023

The ongoing search for an HIV vaccine was among the topics discussed during the 2023 Conference on Retroviruses and Opportunistic Infections (CROI). spoke with Dr. Carl Dieffenbach, Director of the Division of AIDS at NIH’s National Institute of Allergy and Infectious Disease, about some key takeaways from those presentations. Watch our conversation with Dr. Dieffenbach below:

Mosaico Trial Ends
The most recent large-scale HIV vaccine trial was the Mosaico trial. During a CROI special session on HIV vaccine research, Dr. Susan Buchbinder, the co-chair of the Mosaico Study, provided a review of the study, which began in 2019. It involved an investigational HIV vaccine regimen tested among 3,900 men who have sex with men and transgender people in Europe, North America, and South America. The regimen was found to be safe, but it did not provide protection against HIV acquisition. So, the trial was halted last month. Dr. Dieffenbach explained that this was the last of a certain type of vaccine trial.

Future Directions for HIV Vaccine Research
Dr. Dieffenbach added that there are, however, other vaccine concepts now being studied. During the CROI special session on vaccine research, Dr. Larry Corey, co-principal investigator of the NIH-supported HIV Vaccines Trials Network (HVTN), reviewed the history of HIV vaccine research, discussed why it has been so hard to come up with an effective HIV vaccine and discussed future directions for vaccine research. Dr. Dieffenbach noted that while there won’t be an HIV vaccine in the near term, there are early-stage experimental medicine trials underway. Those trials need participants, so Dr. Dieffenbach encouraged anyone interested in learning about current clinical trials or participating in them to visit the HVTN website.

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 website for more information; abstracts, session webcasts, and e-posters will be published there for public access in 30 days.

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