Two HIV vaccine trials launched in Uganda December 23, 2020 One of the volunteers getting the jab PrEPVacc is, for the first time, trialing two HIV vaccine regimens in Uganda, and at the same time testing a new form of daily oral pre-exposure prophylaxis (PrEP) against the existing standard for PrEP. The PrEPVacc trial, testing two ways to prevent HIV at the same time was launched on December 20 and begun giving its first injections and medicines to participants, at the Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine (MRC/UVRI and LSHTM) Uganda Research Unit, an official statement released on December 20, said.