The latest HIV vaccine in a late-stage trial has failed, researchers announced Wednesday, dealing another blow to decades-long efforts to end the HIV/AIDS pandemic.
Called “Mosaico,” the trial began in 2019 as one of three late-stage HIV vaccine studies. About 3,900 men and transgender people aged 18 to 60 received four injections over a 12-month period.
While the vaccine was deemed safe, researchers found similar rates of HIV infection between the placebo and vaccine groups.
Advanced trials of two other vaccines, named ‘Uhambo’ and ‘Imbokodo’, have also yielded disappointing results in recent years.
“It’s obviously disappointing,” said Dr. Anthony Fauci, the longtime head of the National Institute of Allergy and Infectious Diseases (NIAID), told NBC News about the vaccine’s failure.
The post was referred to NIAID for comment. Fauci had previously vowed not to retire from the agency until a successful HIV vaccine was developed.
He expressed optimism that day will come, suggesting “other strategic approaches” in an interview with The New York Times on Wednesday.
“The ultimate method of prevention for any infection, especially a viral infection, is a vaccine that is safe and effective,” said Fauci, who retired last month. “This is why the field will continue to pursue very active research in this area.”
That aborted trial — led by Janssen Pharmaceuticals, part of Johnson & Johnson — is the latest in a string of setbacks in the journey to end the infectious disease four decades after its discovery. The disease has since claimed the lives of more than 40 million people worldwide.
As of 2021, 38.4 million people are living with HIV. Although there is no cure, life expectancy has increased with the use of antiretroviral therapy (ART) and other HIV medications. Pre-exposure prophylaxis (PrEP) can be taken to reduce the chance of infection.
Jennifer Kates, director of global health and HIV policy at the Kaiser Family Foundation, told NBC News that the failure of the Mosaico trial is “a powerful reminder of how elusive an HIV vaccine really is and why this kind of research continues.” to be important”.
“Fortunately, there are already a number of highly effective HIV prevention interventions,” Cates added. “The challenge is scaling them up to reach everyone at risk.”