Hiv protease inhibitor

All of the drugs in this group are reversible inhibitors of the HIV aspartyl protease, which is the viral enzyme responsible for cleavage of the viral polyprotein into a number of essential enzymes (reverse transcriptase, protease, and integrase) and several structural proteins. The protease inhibitors exhibit at least a thousandfold greater affinity for HIV-1 and HIV-2 enzymes than they have for comparable human proteases, such as renin and cathepsin D/E. This accounts for their selective toxicity. The inhibition prevents maturation of the viral particles and results in the production of noninfectious virions. Treatment of antiretroviral naïve patients (those who have never had HIV therapy) with a protease inhibitor and two NRTIs results in a decrease in the plasma viral load to undetectable levels in 60 to 95 percent of patients. Treatment failures under these conditions are most likely due to a lack of patient adherence.