Top stories for HIV Vaccine Awareness Day
The first HIV vaccine clinical trial was launched in 1987 at the NIH Clinical Center in Bethesda, Maryland, according to the HHS. Thirty years later, researchers continue to investigate both preventive and therapeutic HIV vaccines.
In a statement released today on HIV Vaccine Awareness Day, observed annually on May 18, Anthony S. Fauci, MD, director of the NIH’s National Institute of Allergy and Infectious Diseases (NIAID), and Carl W. Dieffenbach, PhD, director of the Division of AIDS at NIAID, said that a recent NIH-funded modeling study suggests that a preventive vaccine with at least 50% efficacy could reduce the number of people living with HIV worldwide by 36% over a period of 15 years.
“Together with the other medical and behavioral prevention modalities that have been proven to decrease the risk of acquiring HIV, a vaccine could change the epidemic’s trajectory,” Fauci and Dieffenbach said in a statement.
However, because HIV continues to rapidly mutate, vaccine development has proven to be one of the most difficult challenges that researchers today face, they added.
“While the pursuit of a safe and effective HIV vaccine is challenging, this prevention strategy holds lifesaving potential and is NIAID’s highest priority for AIDS research,” they wrote. “On this HIV Vaccine Awareness Day, we recognize and thank the thousands of HIV vaccine clinical trial volunteers, researchers, health professionals, activists and others who work together with us toward this goal.”
Meanwhile, at amfAR’s Institute for HIV Cure Research, scientists are currently exploring the use of investigational therapeutic vaccines and drugs, particularly toll-like receptor (TLR) agonists, in what is known as the “shock-and-kill” strategy.
According to Rowena Johnston, PhD, vice president and director of research at amfAR, the Foundation for AIDS Research, a small fraction of immune cells in HIV patients remains infected with a latent virus, even with the use of ART. Since the immune system is unable to detect and, therefore, fight against this latent reservoir, researchers are investigating whether TLR agonists can be used to provoke the virus to replicate and enhance the immune system’s ability to kill the cells producing the virus, possibly with the help of a vaccine.
“Research into whether therapeutic vaccines can be an effective method of curing HIV is still in its early stages and remains unknown,” Johnston told Infectious Disease News. “However, as recent studies indicate, there is potential for these so-called therapeutic vaccines to keep the virus at bay for an extended period of time without antiretroviral drugs, underscoring the importance to move forward with sustaining and energizing research in this field.”
To mark HIV Vaccine Awareness Day, Infectious Disease News compiled a list of the top five stories covering HIV vaccine development:
HIV vaccine development continues after promising early data
Interim study data of a modified HIV vaccine regimen presented at AIDS 2016 demonstrated increased efficacy over previous attempts and supports expansion into larger clinical trials.
This announcement came alongside trial enrollment updates for another HIV vaccine developed by Janssen Pharmaceuticals, and increasing focus on antibody-mediated prevention strategies. Read more.
HIV vaccine candidate enters phase 2b/3 trial
A phase 2b/3 trial led by researchers at the National Institute of Allergy and Infectious Diseases will be the first of its kind in 7 years to assess the efficacy of an HIV vaccine candidate.
The HVTN 702 trial will be conducted across 15 sites in South Africa where 5,400 HIV-uninfected participants aged 18 to 35 years will randomly receive the investigational vaccine or placebo. The vaccine is based on a regimen that was evaluated in the RV144 trial, conducted in Thailand. Results from RV144, released in 2009, showed that the vaccine was 31.2% effective at preventing HIV over a follow-up period of 3.5 years. For the current trial, the vaccine was modified specifically for HIV subtype C, the predominant subtype in southern Africa. Read more.
IAVI, Selexis expand collaboration for development of HIV vaccines
Selexis SA announced it has expanded its collaboration with the International AIDS Vaccine Initiative (IAVI) to develop high-performance research cell banks for the manufacturing of multiple HIV envelope proteins to induce the generation of neutralizing antibodies against HIV via vaccination.
“Manufacturing of engineered HIV proteins in consistent quantity and quality is critical for further development of promising vaccine candidates toward early clinical testing,” Labeeb Abboud, senior vice president of business development at IAVI, said in a press release. “We are pleased to extend our collaboration with Selexis to expedite the development of broadly effective vaccines that will be needed to help end the AIDS epidemic.” Read more.
Researchers investigate early stag es of HIV-neutralizing antibody
Scientists at The Scripps Research Institute (TSRI) and collaborating institutions have identified and characterized an immature, or “teenage,” antibody with broadly neutralizing signatures isolated from an elite controller. The researchers said their findings, published in Immunity, may be useful for future HIV vaccine development.
“This is actually the first example of how we can go back to the really early stage to see how this particular antibody lineage was born and can develop,” TSRI researcher and biologist Jiang Zhu, PhD, said in a press release. Read more.
TSRI scientists capture de tailed picture of HIV structure
Researchers from The Scripps Research Institute (TSRI) have captured a high-resolution image of an almost fully intact HIV protein responsible for infecting host cells. The image revealed potentially vulnerable targets for broadly neutralizing antibodies, which may help guide vaccine development.
“This structure has been elusive because its fragility typically causes it to fall apart before it can be imaged,” Andrew Ward, PhD, associate professor at TSRI, said in a press release. “Now that we know what the native state looks like, the next step is to look at vaccine applications.” Read more.
Mothe B, et al. Abstract 119LB. Presented at: Conference on Retroviruses and Opportunistic Infections; Feb. 13-16, 2017; Seattle.