The initial testing of two combined vaccines in Africa, aimed at preventing HIV, has been stopped due to the determination of researchers that it was not effective.
The pre-exposure prophylaxis vaccine (PrEPVacc) was being tested on 1,500 people aged between 18 and 40 in Uganda, Tanzania and South Africa.
The trial, led by African researchers, commenced in December 2020. However, it was halted in the previous month following an interim evaluation of its progress. The conclusive findings will most likely be disclosed in late 2024.
According to Dr. Eugene Ruzagira, who is the trial director at the Uganda Virus Research Institute (UVRI) and an assistant professor of epidemiology at the London School of Hygiene & Tropical Medicine, the administration of vaccinations to participants in the PrEPVacc trial has been halted. This decision was made by an independent data-monitoring committee after analyzing the data collected thus far. They have determined that there is a low probability of proving that the vaccines being tested can effectively lower the risk of contracting HIV.
The PrEPVacc experiments, overseen by African scientists and aided by European experts, examined two variations of HIV in order to determine their effectiveness in preventing infection among high-risk populations. The projects received a €15m (£12.8m) grant from the European Union’s European & Developing Countries Clinical Trials Partnership.
Dr. Jonathan Weber, a sponsor of the trial from Imperial College London, stated that clinical trials are conducted in order to find answers to questions. The study aimed to determine if the combination vaccine regimens developed over 20 years in the PrEPVacc program should be discontinued or further developed in order to prevent HIV.
He stated that, although we are still waiting for the final results and analysis of each product, he believes that our current findings have put an end to this generation of potential HIV vaccines.
Earlier attempts in South Africa to trial the sole vaccine that displayed some efficacy in preventing HIV – the RV144 from Thailand – were terminated in February 2020 due to interim findings indicating its ineffectiveness.
UVRI’s chief investigator for PrEPVacc, Prof Pontiano Kaleebu, stated that creating a successful vaccine to protect against HIV is a crucial objective for Africa.
He stated that it is crucial to prioritize this goal, especially since there are currently no HIV vaccines being tested for effectiveness globally.
“We have made significant progress in our efforts to prevent HIV, but we must now explore new methods and technologies in order to continue moving forward.”
There are approximately 39 million individuals globally who have HIV, with over 25 million of them residing in sub-Saharan Africa.
At a conference on Aids in Zimbabwe, Ruzagira expressed his optimism on Wednesday. Despite the challenges in the scientific field, he has strong confidence that a vaccine for HIV will eventually be created.
The RV144 vaccine was tested in Thailand from 2003 to 2006, and it showed a reduction in infection rates by nearly one-third after three years.
Source: theguardian.com