Human Trials of 'Global HIV Vaccine' Begin

Human testing of a new experimental HIV vaccine has been launched in southern Africa, the first time in more than a decade that two big HIV vaccine efficacy trials are being carried out concurrently.

Eager to find an effective and dependable protective shot against the virus that causes AIDS, scientists have started another large efficacy study of a two-vaccine combination developed by Johnson & Johnson with the US National Institutes of Health (NIH) and the Bill & Melinda Gates Foundation.

Another HIV vaccine study of a similar scale, also backed by NIH, began last November. Both studies aim to surpass the results of a 2009 trial of a different vaccine in Thailand that showed a 31 percent reduction in infections. According to J&J Chief Scientific Officer Paul Stoffels, it is possible to achieve effectiveness above 50 percent.

"That is the goal....