AdvertisementRising Cost Of PrEP To Prevent HIV Infection Pushes It Out Of Reach For ManyJune 30, 2018Shefali LuthraAnna GormanfacebookEmailGilead Sciences makes Truvada, a medicine known generically as "pre-exposure prophylaxis," or PrEP. Consistent, daily doses of the drug are thought to reduce the risk of getting HIV from sex by more than 90 percent. (Paul Sakuma/AP)