This archive report was first published on 1 September 2021.
Johnson & Johnson's highly anticipated HIV vaccine has failed to show adequate protection in a clinical trial involving over 2,600 young women in sub-Saharan Africa, according to the company and US health authorities.
Although the vaccine was found to be safe, with no serious side effects, its efficacy in preventing HIV infection was just over 25 percent, based on an analysis two years after the women received their first dose.
The trial, known as the 'Imbokodo' trial, began in 2017 and involved participants from Malawi, Mozambique, South Africa, Zambia, and Zimbabwe.
As a result, the trial will now be halted, and the participants will be told whether they received the vaccine or placebo.
However, the company will continue a parallel trial involving men who have sex with men and transgender individuals that is taking place in the Americas and Europe, where vaccine composition differs and so do the prevalent HIV strains.
Paul Stoffels, chief scientific officer of J&J, thanked the women who participated and the company's partners in a statement.
“While we are disappointed that the vaccine candidate did not provide a sufficient level of protection against HIV infection in the Imbokodo trial, the study will give us important scientific findings in the ongoing pursuit for a vaccine to prevent HIV,” he said.
Anthony Fauci, director of the US National Institute of Allergy and Infectious Diseases, added, “We must apply the knowledge learned from the Imbokodo trial and continue our efforts to find a vaccine that will be protective against HIV.”
The J&J vaccine uses similar adenovirus technology to its Covid-19 vaccine and was delivered with four vaccinations over a year.
Researchers found that 63 participants who received the placebo and 51 who received the vaccine became infected with HIV, meaning the efficacy was 25.2 percent.
The participants were offered pre-exposure prophylaxis medication (PrEP) to help prevent HIV infection during the clinical trial.
Despite the disappointing results, research continues, and scientists have made huge strides in HIV treatment in the four decades since the first cases of AIDS were documented.
Oral PrEP, when taken every day, reduces the risk of infection by 99 percent, but access to medication remains unequal across the world and even within wealthy countries, making a vaccine a high priority.
Earlier this month, a trial of two vaccines by Moderna based on the same mRNA technology behind the company's Covid vaccine was posted on a government website, with recruitment to begin September 19.
