Saquinavir (Invirase)

Saquinavir (Invirase) is a protease inhibitor that reduces the amount of virus in the body. Anti-HIV drugs such as saquinavir slow down or prevent damage to the immune system and reduce the risk of developing AIDS-related illnesses. Protease inhibitors act by blocking HIV’s protease or proteinase, the 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. Saquinavir was the first protease inhibitor to be licensed .

A previous soft-gel formulation of saquinavir was known by the trade Fortovase. It was licensed in Europe in August 1998, but production stopped in early 2006, and its authorisation was withdrawn in June 2006. This original, hard gel capsule formulation was replaced by a new 500mg version of Invirase in tablet form, which received marketing approval in the United States in December 2004 and in Europe in May 2005. This formulation cuts the pill burden from five to two tablets of saquinavir twice a day.

Another formulation of saquinavir, called the enhanced oral formulation (EOF) or soft gelatin capsule (SGC) formulation is no longer available. During development, saquinavir was known by the codename Ro 31-8959.