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

Indinavir is a protease inhibitor. Protease (or proteinase) is 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.

Indinavir was previously known by the codenames MK-639 and L-735,524. It is manufactured by Merck Sharp & Dohme Ltd., who market the drug as Crixivan. Several generic versions of indinavir are manufactured by Indian companies, including Indivir (Cipla), Indivex (Aurobindo), Virodin (Ranbaxy) and Indivir (Genixpharma).

In March 1996, indinavir was approved for use in the United States. In October 1996, it was approved throughout the European Union for use in combination with nucleoside reverse transcriptase inhibitors (NRTIs) for treating HIV-positive adults with advanced or progressive immunodeficiency.