Darunavir (Prezista) is an anti-HIV drug that reduces the amount of virus in the body. Anti-HIV drugs such as darunavir slow down or prevent damage to the immune system and reduce the risk of developing AIDS-related illnesses.

Darunavir is a new protease inhibitor. Protease (or proteinase) is the protein or enzyme that HIV uses to break up large viral proteins so new HIV particles can be made. For more information about how protease inhibitors work, see Protease inhibitors.

Darunavir was developed by the Belgian company Tibotec. Tibotec was bought by the United States company Johnson & Johnson in 2002. Darunavir is designed to be active against HIV that is resistant to currently available protease inhibitors. During development, it was known as TMC114.

Darunavir was granted accelerated approval for use in the United States in June 2006. It is now available for patients in the United States whose HIV infection is not responding to treatment with other anti-HIV drugs.

Darunavir was granted marketing approval in the European Union in February 2007 for treatment-experienced adults who have failed more than one regimen containing a protease inhibitor.