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A statement from the HIV Vaccine Trial Network on the PrEPVacc study announcement

PrepvaccSEATTLE — Dec. 5, 2023 — Today PrEPVacc announced that vaccinations have been stopped in its HIV Phase 2 prevention study of experimental vaccine regimens running in East and Southern Africa due to lack of demonstrated efficacy in preventing HIV acquisition. “While this is not the result the study team was looking for, these results underscore the continued importance of finding a vaccine to prevent HIV,” said Dr. Larry Corey, a virologist and principal investigator of HIV Vaccine Trials Network’s (HVTN) Leadership and Operations Center, headquartered at Fred Hutch Cancer Center in Seattle.

“The scientists and team who have led the study are to be commended for running an excellent study which, even if the results are not those hoped for, move the field forward with a definitive result. We look forward to reading the analysis and learning whether the correlates of protection in this study corroborate HVTN’s recent non-neutralizing antibody vaccine study findings and provide findings that can lead to a successful HIV vaccine,” said Corey.

Professor Glenda Gray, President and Chief Executive Officer of the South African Medical Research Council (SAMRC), said, “The search for an effective HIV vaccine remains critical as the incidence rates in our communities continue to be unacceptably high demonstrating the urgent need to continue to invest in  biomedical interventions that can ultimately control HIV at a population level.”

“When persons at risk, including men who have sex with men in America and women and adolescent girls in sub-Saharan Africa, are acquiring HIV at over 4% per year despite these efforts, we must question our current ability to achieve HIV pandemic control with the modalities currently available,” said Gray

“Despite the many challenges the HIV vaccine field has faced and continues to face, the findings of high and sustained incidence, suggest that to achieve lasting HIV epidemic control a preventive vaccine is going  to be essential. This has been true for virtually all other viruses with pandemic potential, and HIV is not likely to be an exception,” said Corey.

About the HIV Vaccine Trials Network (HVTN)
The HIV Vaccine Trials Network (HVTN) is the world’s largest publicly funded international collaboration facilitating the evaluation of vaccines to prevent HIV/AIDS. HVTN helps advance the field of vaccinology, social and behavioral sciences, statistics and immunology, as well as tuberculosis and COVID-19 vaccines. The HVTN’s mission is to fully characterize the safety, immunogenicity and efficacy of HIV vaccine candidates with the goal of developing a safe, effective vaccine as rapidly as possible for prevention of HIV globally. Funding is provided by public and private sources. The National Institute of Allergy and Infectious Diseases (NIAID) at the U.S. National Institutes of Health, is the primary funder and sponsor of the majority of trials conducted by the HVTN. The Network’s headquarters are at Fred Hutchinson Cancer Center in Seattle, Washington.


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