May 17, 2022

According to a study record filed to the United States National Institutes of Health Clinical Trials registry, Moderna could begin human clinical trials for two new mRNA-based HIV vaccines as early as September 19.

Science Alert’s Fiona Macdonald said that the vaccines would use a technique similar to the ground-breaking mRNA method used in their COVID-19 vaccine. The human trial is scheduled to last through May 2023.

The first mRNA vaccines used in people were the Pfizer-BioNTech and Moderna COVID-19 vaccines. mRNA vaccines function by instructing cells to produce fragments of the identical proteins found on a virus’s outer shell. The proteins subsequently stimulate immune cells to recognize and destroy the virus, according to Popular Science’s Sarah Chodosh.

The trials will assess the two experimental vaccines’ safety and their ability to generate a diverse array of bNABs against HIV. According to the Independent, the vaccine will be administered to 56 healthy people aged 18 to 56 who do not have HIV. The experimental trials will involve four groups, with two receiving a combination of vaccines and the other two receiving only one of the two vaccines. Each group will be informed of the vaccine kind they are receiving.

Developing an HIV vaccine is difficult because the retrovirus integrates into the human genome 72 hours after transmission. A significant amount of neutralizing antibodies (bNABs) must be present during transmission to prevent infection. Both of Moderna’s HIV vaccinations will contribute to resolving this issue by triggering the release of bNABs in the body.

During the first round of the trials, researchers are primarily interested in determining whether the vaccine is safe and induces an immunological response. The second and third phases will evaluate the efficacy of the vaccine in preventing HIV infections.

“Moderna are testing a complicated concept which starts the immune response against HIV,” says Robin Shattock, an immunologist at Imperial College London, to the Independent. “It gets you to first base, but it’s not a home run. Essentially, we recognize that you need a series of vaccines to induce a response that gives you the breadth needed to neutralize HIV. The mRNA technology may be key to solving the HIV vaccine issue, but it’s going to be a multi-year process.”