Pre-exposure prophylaxis for HIV prevention: How to predict success

摘要

Use of antiretroviral drugs to prevent sexual transmission of HIV-1 has been a critical priority since their development. In the past 2 years results from seven important prevention trials have been reported (table). One of the trials, HPTN 052, showed nearly complete prevention of HIV transmission when viraemia was suppressed. The other studies focused on antiretroviral agents for pre-exposure prophylaxis: two used 1% tenofovir gel (CAPRISA 004 and VOICE), four used oral tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) in combination (iPrEX, TDF2, Partners in Prevention [PIP], and Fem-PrEP), and two used oral TDF alone (VOICE and PIP). Somewhat confusingly, the findings of these studies have led to reports both of successful prevention of HIV infection (CAPRISA 004, iPrEx, TDF2, and PIP) and of futility (VOICE and Fem-PrEP).