New HIV Vaccine Shows Promising Initial Results

An AIDS vaccine with messenger RNA (mRNA) technology has shown its first promising results in animals, the researchers announced on Thursday (9).

The vaccine was considered safe after being administered to monkeys, with a 79% reduction in the risk of infection due to exposure to the virus. However, the immunizing agent requires improvements before being tested in humans.

“Despite nearly four decades of efforts by the world scientific community, an effective vaccine to prevent HIV remains an unattainable goal,” said immunologist Anthony Fauci, study co-author and White House consultant on Covid-19’s health crisis.

“This experimental messenger RNA vaccine combines several features that could overcome the failures of other experimental HIV vaccines and represents a promising approach,” added the director of the US National Institute of Allergy and Infectious Diseases (NIAD) in a statement.

Scientists from this institute worked together with researchers from Moderna, the American company responsible for one of the most used vaccines against Covid.

The study was published on Thursday in the prestigious journal Nature.

The vaccine was tested first in mice and then in monkeys, which received several booster doses over the course of a year.

Despite the high doses of mRNA, the product was well tolerated, causing mild side effects such as temporary loss of appetite.

By week 58, all monkeys developed detectable levels of antibodies. From week 60 onwards, the animals were weekly exposed to the virus through the rectal mucosa.

Since monkeys are not vulnerable to HIV-1, which infects humans, the researchers used another similar virus, simian HIV (SHIV).

After 13 weeks, only two of the seven immunized primates were not infected. While the others who were not vaccinated developed the disease after about three weeks, those who were immunized took an average of eight weeks.

“This level of risk reduction can have a significant impact on viral transmission,” the study emphasized.

The vaccine works by providing genetic instructions to the body, causing the creation of two characteristic proteins of the virus. These group into specific pseudoviruses (VLPs), simulating an infection to induce an immune system response.

Scientists noted, however, that the levels of antibodies produced were relatively low and that a vaccine that required multiple injections would be difficult to apply to humans.

They also hope to improve the quality and quantity of the VLP generated, before testing the vaccine in humans.