South Africa and the United States are to start testing a new preventative HIV vaccine and have begun enrolling participants to take part in a clinical trial.

According to US state research agency the National Institutes of Health (NIH), the vaccine, called VIR-1388, is designed to help a body’s T-cells, these are part of the immune system and patrol and inspect other cells for problems.

The vaccine is intended to instruct the immune system to produce T-cells “that can recognise HIV and signal an immune response to prevent the virus from establishing chronic infection”.

The vaccine trial is funded by the NIH, the Bill and Melinda Gates Foundation and the US company Vir Biotechnology.

The study will enrol 95 HIV-negative participants at four sites in South Africa and six sites in the US.

The initial results of the vaccine trial will be announced in late 2024, but some participants will continue with the trial for three years.

In 2020, the NIH suspended the testing of another HIV vaccine in South Africa after a review found that the vaccine was ineffective in preventing HIV transmission.