Evaluating the Safety and Tolerability of Antiretroviral Drug Regimens Used as Pre-Exposure Prophylaxis to Prevent HIV Infection in At-Risk Men Who Have Sex With Men and in At-Risk Women

Pre-exposure prophylaxis (PrEP) is a method of preventing HIV infection through the use of antiretroviral (ARV) medications before exposure to HIV. This study will evaluate the safety and tolerability of four ARV regimens in preventing HIV infection in men who have sex with men who may be at risk of getting HIV infection through sex and women who may be at risk of getting HIV infection through sex. The four ARV regimens being evaluated are maraviroc (MVC), MVC plus emtricitabine (FTC), MVC plus tenofovir disoproxil fumarate (TDF), and TDF plus FTC. The MVC-containing arms will be compared to TDF/FTC alone and in combination.