The International AIDS Conference in Durban, South Africa, in July 2016, has renewed interest and momentum around HIV prevention. High and sustained HIV incidence rates—about 2 million people acquiring HIV every year for the past 5 years—highlight the need for new prevention technologies for populations at substantial risk of HIV.1 As many as 7000 new infections a week are occurring in the most vulnerable adolescent girls and young women in eastern and southern Africa. 75% of young people in sub-Saharan Africa living with HIV are adolescent girls and young women age 15–24 years; AIDS is the leading cause of death for girls age 10–19 years in Africa.
