An experimental HIV vaccine increased participants’ broadly neutralizing antibody (bnAb) precursor B cells that enable the body to develop bnAb-producing B cells and fight HIV, researchers reported in study results published in December 2022. The progress comes more than a decade after researchers at the National Institutes of Health’s (NIH’s) National Institute of Allergy and Infectious Diseases Vaccine Research Center first discovered the rare class of antibodies.
The study supports NIH’s HIV/AIDS research priorities:
- Reduce the Incidence of HIV, including supporting the development of safe and effective vaccines, microbicides and pre-exposure prophylaxis.
- Develop Next-Generation HIV Therapies with improved safety and ease of use.
- Conduct Research Toward HIV Cure.
- Address HIV-Associated Comorbidities, Coinfections, and Complications through research designed to decrease and/or manage these conditions.
- Advance Cross-Cutting Areas of research in the basic sciences, behavioral and social sciences, epidemiology, implementation science, information dissemination, and research training.
Researchers found that the cells increased more than 500-fold in 97% of vaccine recipients after one of two doses compared to prevaccination. Forty-eight participants received either a low or high dose of the vaccine or a placebo. Immunization consisted of two doses, given eight weeks apart.
Researchers examined the receptors that B cells use to recognize pathogens and found that they shared several molecular features with bnAbs. The researchers also noted early steps in the body’s development of bnAbs, including increased receptor gene variants after the second vaccine dose and increased receptor affinity for the vaccine.
“These findings establish proof of concept and a crucial first step for the strategy of eliciting bnAbs against HIV,” Brian Doctrow, PhD, assistant editor for NIH Research Matters, said. “But this priming vaccine alone cannot induce production of mature bnAbs. Booster vaccines will be needed to elicit bnAb production and protection against HIV. The results support further development of such boosters.”
“This trial and additional analyses will help inform design of the remaining stages of a candidate HIV vaccine regimen—while also enabling others in the field to develop vaccine strategies for additional viruses,” Julie McElrath, MD, PhD, director of the vaccine and infectious disease division at Fred Hutchinson Cancer Center and one of the study authors, said.
One of NIH’s research priorities is to address HIV-associated comorbidities, coinfections, and complications, including cancer and cancer-causing infections. Preventing HIV/AIDS can also help prevent cancer. Help make progress toward a vaccine by advocating for increased research funding.