Gilead is investing in clinical research to develop new medical interventions that address the health needs of developing countries. At the end of 2008, Gilead was involved in 36 ongoing studies that had enrolled more than 13,500 patients in Asia, Africa and Latin America. The largest of these studies is the Development of Antiretroviral Therapy (DART) study with two sites in Uganda and one site in Zimbabwe

Clinical studies supported by the US Centers for Disease Control and Prevention, the National Institutes of Health and other public health leaders also are underway to evaluate the potential of Viread® and Truvada® to prevent HIV infection in high-risk individuals. For these studies, Gilead provides Viread®, Truvada® and/or placebo at no cost. Preliminary results from these studies may be available in 2010.