South Africa’s Medical Research Council (MRC) is teaming up with scientists from eight countries on the continent in an US-funded effort to select an immunization candidate against the virus that causes AIDS.

Molecules that are potentially capable of eliciting an immune response against the virus have already been identified for development into vaccine contenders, said Glenda Gray, the president of the South African MRC.

Finding an HIV vaccine has eluded scientists for decades and while there are preventative treatments, they have to be taken regularly. Once contracted, life-long use of antiretroviral drugs is necessary to stop the auto-immune disease, which killed 630 000 people globally last year, from becoming fatal.

The $45-million funding is timely as the US President’s Emergency Plan for AIDS Relief program waits for reauthorization while politicians debate its reach. PEPFAR was initiated in 2003 by then President George W Bush. It has saved an estimated 25-million lives and allowed 5.5-million children to be born free of the HIV virus that causes AIDS, John Nkengasong, the head of PEPFAR, said earlier this year.

The MRC is also talking to scientists to get other immunogens that are based on two of the most common types of HIV virus found in Africa, and plans to conduct its first HIV vaccine discovery study within a year, Gray said.

To deliver the chosen molecules in the most effective way, a wide variety of options are being considered, Gray said. This includes mRNA technology, which was used in some Covid-19 shots, as well as protein and nano-particle based options. It’s also evaluating other platforms with new ingredients that may help create a stronger immune response in people receiving the vaccine.

Separately, a trial of a preventive HIV vaccine candidate, known as VIR-1388, began last month in the US and South Africa, which has the world’s largest number of people infected with HIV — about 13% of its 61-million population.