How the hunt for an HIV vaccine helps research on Covid-19 – and vice versa

Researchers around the world, including in France, where a groundbreaking trial is underway, are continuing their work on a vaccine against HIV, the virus that causes AIDS. Serawit Bruck-Landais, research director at Sidaction (AIDS action), a French charity and organizer of a joint fundraiser in collaboration with FRANCE 24, spoke about the search for an HIV vaccine – and its link to coronavirus research.

The fight against HIV, which has taken the back seat during the Covid-19 pandemic, returned to the forefront in France on Friday during the 28th edition of Sidaction, an annual TV fundraising event that takes place until Sunday.

The virus that causes AIDS has killed more than 32 million people worldwide since the 1980s. Researchers are continuing their research and creating new initiatives to develop a vaccine to overcome this ailment.

The health crisis caused by the coronavirus pandemic has slowed down research, although several studies have recently been resumed, said Bruck-Landais, head of the research and health department at Sidaction, FRANCE 24

The subject of a vaccine strategy has mobilized research since the beginning of the HIV epidemic, Bruck-Landais said, citing “many failures and vaccine projects or vaccination strategies that have since been developed thanks to our greater knowledge of the virus and the immune system”.

This development now makes it possible to test complete strategies that can circumvent the problems with HIV, an unstable virus that mutates and from which many subtypes arise.

Several trials and “a rather innovative strategy”

So how is the research today? “There is a very advanced phase 3 study that we expect results from 2022,” said Bruck-Landais. This test tests a “mosaic” strategy that makes it possible to use different parts of the HIV virus, corresponding to different subtypes, in order to be able to prevent most of the virus that is circulating around the world.

A study for a preventive vaccine launched in France by the Vaccine Research Institute, a laboratory created by the French National Agency for Research on AIDS and Viral Hepatitis (ANRS) and the University of Paris-Est Créteil, is among other trials currently underway. in phase 1.

This study “tests a rather innovative strategy for optimizing dendritic cells: central immune cells that orchestrate our immune response,” Bruck-Landais explained. The idea is to “target these cells so that they can recognize HIV viruses and then present them with antigens to stimulate antibody production”.

The Vaccine Research Institute began a volunteer interview at the end of February and planned three recruitment phases. The test aims to “test the vaccine’s safety,” Bruck-Landais said, and its goal is currently to find out if the vaccine elicits an immune response and if the planned doses cause side effects. The first volunteers receive their injections in mid-April.

‘Interactions and lessons to learn’

While research continues, it has encountered difficulties linked to the health crisis. “Trials have been interrupted or slowed down,” Bruck-Landais said, especially because it became impossible to monitor thousands of participants due to “travel problems and health conditions.” Expected results have thus been delayed.

However, the head of research noted a positive consequence of the health crisis: It encouraged researchers from HIV and Covid-19 to collaborate. In particular, this collaboration opened new avenues for studies on messenger RNA technology, which is used for the Pfizer-BioNTech and Modern Covid-19 vaccines. “This technology has never been tested for HIV, but researchers have been studying it for several months to apply it to HIV,” says Bruck-Landais.

The two viruses are still very different, she said, noting that vaccine strategies tested for HIV have not been successful, while several Covid-19 vaccines have been found in record time.

“One is the coronavirus – Sars-CoV-2 – and the other is a retrovirus – HIV,” she explained. “HIV mutates enormously. In each viral cycle, it generates at least 20 mutations each time it multiplies, and on top of that there are at least four different subtypes circulating in the world.

“The vaccine strategy is less complicated when it comes to getting the immune system to recognize a single virus than thousands of variants and at least four subtypes.”

The state of HIV research has benefited coronavirus research, she added. Vaccine strategies tested for HIV and not working are used for Covid-19 vaccines, including the adenovirus vaccine (used by AstraZeneca and Johnson & Johnson).

“There are interactions and lessons to be learned on both sides.”

HIV research expert Serawit Bruck-Landais speaks to FRANCE 24

In France, 173,000 people live with HIV and an estimated 24,000 more are unknowingly infected. A reduction in HIV screening during the Covid-19 pandemic – around 650,000 tests by 2020, according to Santé Publique France, the national health service – has raised fears of an epidemic of 2022.

This article has been translated from the original into French.