<unk>  is an antiretroviral drug used in HIV therapy. It falls in the protease inhibitor class. Two formulations have been marketed:
a hard-gel capsule formulation of the mesylate, with trade name Invirase, which requires combination with ritonavir to increase the<unk>  bioavailability;
a soft-gel capsule formulation of<unk>  (microemulsion, orally-administered formulation), with trade name Fortovase.
Both formulations are generally used as a component of highly active antiretroviral therapy (HAART).<unk>  was developed by the pharmaceutical company Roche.<unk>  was the first protease inhibitor (and sixth antiretroviral) approved by the Food and Drug Administration (FDA). Within 2 years of its approval, and that of ritonavir 4 months later, annual deaths from AIDS in the United States fell from over 50,000 to approximately 18,000 
. It was approved on December 6, 1995, as Invirase, a poorly-absorbed hard gel capsule which quickly led to viral resistance in many of the pioneer patients.[citation needed] The manufacturer, Roche, requested and received approval of Invirase via the FDA's "Accelerated Approval" program, a process designed to speed drugs to market for the treatment of serious diseases. This decision was controversial, amid disagreement between AIDS activists over the benefits of thorough testing versus early access to new drugs.
It was approved again on Nov 7, 1997 as Fortovase, a soft gel capsule reformulated for improved bioavailability. Roche announced in May 2005 that, owing to reduction in demand, Fortovase would cease being marketed early in 2006 in favour of Invirase boosted with ritonavir.
Saquinavir
Fosamprenavir
Entecavir
Abacavir
Telaprevir
Tipranavir
Lamivudine
Enfuvirtide