Guidance on Pre-exposure Oral Prophylaxis (PrEP) for Serodiscordant Couples, Men and Transgender Women Who Have Sex with Men at High Risk of HIV: Recommendations for Use in the Context of Demonstration Projects

Clinical trials on PrEP began in 2005. These trials have focused on the effectiveness of PrEP among people who inject drugs, HIV serodiscordant couples, heterosexual men and women, women at higher risk of HIV exposure, and men and transgender women who have sex with men (MSM-TG). Of these, two have completed as planned, one was stopped early for effectiveness, and two others were stopped or had arms discontinued for reasons of futility.