An early-stage HIV vaccine clinical trial in South Africa has determined that an investigational vaccine regimen is safe and generates comparable immune responses to those reported in a landmark 2009 study showing that a vaccine can protect people from HIV infection. Consequently, the National Institute of Allergy and Infectious Diseases (NIAID) and its partners have decided to advance the experimental HIV vaccine regimen into a large clinical trial. This new study, called HVTN 702, is designed to determine whether the regimen is safe, tolerable and effective at preventing HIV infection among South African adults. The trial is slated to begin in November 2016, pending regulatory approval.