Table 1.

Salient features of prior studies on pre-exposure prophylaxis of HIV

Trial name	Study site	Intervention	Study population	Protection
iPrEx	North and South America, Thailand, South Africa	daily oral TDF-FTCa	2499 HIV sero-negative men or transgender women who have sex with men	44% (15% – 63%)
FEM-PrEP	Kenya, South Africa, Tanzania	daily oral TDF-FTC	2120 HIV negative women	halted early for lack of efficacy
PIP	Kenya and Uganda	daily oral TDF-FTC or TDFb	4747 HIV-1 serodiscordant heterosexual couples	67% (44% – 81%) TDF 75%(55%–87%) TDF-FTC
TDF2	Botswana	daily oral TDF-FTC	1219 HIV sero-negative men and women	62.2% (21.5% –83.4%)

^aTDF-FTC: Tenofovir and Emtricitabine combination

^bTDF: Tenofovir disoproxilfumarate