The first large-scale NIH sponsored clinical trial ‘HPTN 084’ of a long-acting injectable medication for HIV prevention in sexually active women has begun. The study in southern and eastern Africa will examine whether a long-acting form of the investigational anti-HIV drug cabotegravir injected once every eight weeks can safely protect women at risk for HIV infection. The only drug regimen currently licensed for HIV pre-exposure prophylaxis, or PrEP, is the anti-HIV medication Truvada taken daily as an oral tablet.