A new vaccine against HIV, the virus that causes Aids, is being tested in South Africa in what scientists say is the first large study of an HIV vaccine's effectiveness since 2009. The study - code-named HVTN 702 - aims to enroll 5,400 sexually active young men and women.
The vaccine being tested is a modification of one used in a trial in Thailand in 2009, which had a protection rate of about 30% that wore off over time, and therefore could not be used for the general population. Scientists produced a strengthened version, furthered altered to work against a more aggressive HIV strain in South Africa. A small study conducted earlier in 2016 confirmed the vaccine candidate to be safe and promising enough for use in a major study.
Another reason the trial is taking place in South Africa: about seven million people here are living with the virus; 19 percent of adults have HIV and more than 1,000 people become infected with the virus every day. "We’d be happy if this vaccine were even 45 or 50 percent effective,” said Gita Ramjee, director of the HIV Prevention Research Unit at the Medical Research Council in Durban, which is running two of the 15 trial sites. “Even a modestly effective vaccine like that would have a huge impact here.”