Pictured above: Professor Chen Zhiwei and team members Niu Mengyue (left), and Liu Li.
A promising new universal HIV-1 antibody candidate could rewrite how HIV treatment and prevention are approached. Researchers believe the drug would work much longer than daily antiretrovirals or PrEP, and would be effective for many HIV-1 strains.
A team led by scientists at AIDS Institute and Department of Microbiology, Li Ka Shing Faculty of Medicine of The University of Hong Kong have developed an antibody that protects against the full myriad of HIV-1 strains. The findings were published in the April issue of Journal of Clinical Investigation.
The team invented a “single gene-encoded tandem broadly neutralizing antibody,” called BiIA-SG, which researchers say can kill two birds with one stone. Broadly neutralizing antibodies are shortened as bNAbs and could play a role in the race for an effective HIV vaccine.
BiIA-SG attacks 124 genetically divergent global HIV-1 strains. It targets HIV cells during two essential steps of HIV-1 entry into target cells. Studies—using modified “humanized” mice—have indicated that the drug is effective against multiple strains of HIV and also promotes the elimination of dormant infected cells. Uninfected mice were protected from the virus for about a week. Forty-two percent of the already-infected mice had an undetectable level of HIV for at least four weeks after one injection of the drug.
“Scientists have invented a universal antibody drug against HIV/AIDS,” researchers wrote. “By engineering a tandem bi-specific broadly neutralizing antibody, the team found that this novel antibody drug is universally effective not only against all genetically divergent global HIV-1 strains tested but also promoting the elimination of latently infected cells in a humanized mouse model.”
As you may already know, HIV cells can go into a resting state and stop producing more HIV cells. These are called latent HIV reservoirs, and they are one of the reasons that finding a cure for HIV is so difficult.
While HIV remains defined as an incurable disease, a therapeutic cure or an effective vaccine could end the pandemic. The economic burden of daily antiretrovirals is the reason new approaches to fighting HIV are needed.
The current estimated annual cost of antiretroviral drugs is over HK$550 million for one year in Hong Kong, not including other costs. HIV rates have more than doubled from 4,443 diagnostic cases in 2009 to 9,091 in 2017, despite having robust combination therapy programs. The PrEP treatment Truvada is HK$8,000 (Over $1,000 USD) to HK$10,000 for one month’s supply, a cost most can’t afford.
But the new antibody being developed in Hong Kong could last much longer than a daily pill. “We are doing further modifications ... to make sure the drug concentration can be maintained for much longer time. We are targeting [for this to be] weeks or even months,” Professor Chen Zhiwei, professor of microbiology at the University of Hong Kong, told the South China Morning Post.
There are at least 60 known different epidemic strains of HIV-1, but if a person becomes infected with two or more strains, the strains can combine to form what is called a recombinant.
In recent years, a surge of reported HIV cases has reignited the need for more HIV research. The research team hopes that BiIA-SG will be the first anti-HIV-1 antibody drug for clinical development that can say "Made in Hong Kong".