(NewsNation) — A trial of an experimental HIV vaccine that took place in Uganda, Tanzania and South Africa was halted after preliminary data suggested it would not be effective.
The vaccine, which was part of the PrEPVacc program, was tested on around 1,500 people between 18 and 40, according to The Guardian. Reuters reports participants were drawn from populations at a high risk of infection.
Two different combinations of experimental HIV vaccines were being tested during this trial, which African researchers led with support from various European institutions.
A form of oral pre-exposure prophylaxis, or PREP, which reduces the risk of getting HIV, was also being tested. That trial is ongoing.
Pontiano Kaleebu, the chief investigator for the program, told Reuters the program’s data safety monitoring committee had said that even if the trial continues, researchers would not be able to show the vaccine works.
Another 2020 trial by researchers in South Africa was terminated after tests of a vaccine given to more than 5,000 failed to show benefits. Earlier this year, the Janssen Pharmaceutical Companies of Johnson & Johnson stopped a trial called Mosaico, again because the vaccine being tested was found to be ineffective.
Still, Dr. Eugene Ruzagira, trial director from the Uganda Virus Research Institute and assistant professor of epidemiology at the London School of Hygiene and Tropical Medicine, remains optimistic, The Guardian writes.
“The scientific hurdles are high, but I have equally high hopes that an HIV vaccine will be developed one day,” Ruzagira said at an AIDS conference in Zimbabwe on Wednesday, per the outlet.
Final results from the trial are expected to be available to the public in late 2024.
HIV has killed about 40 million people around the world, and another 39 million are living with the disease.
Reuters contributed to this story.