▴ Amprenavir is a viral protease inhibitor with specificity for the HIV protease enzyme. The resistance profile of amprenavir appears to differ from that of other protease inhibitors such as saquinavir and indinavir.
▴ Twelve hours after single-dose administration of amprenavir 1200mg to HIV-infected individuals, the mean plasma concentration of the drug was more than 10-fold greater than the 50% inhibitory concentration for HIV-1IIIB in peripheral blood lymphocytes.
▴ In a small nonblind study, amprenavir monotherapy increased CD4+ cell count and decreased viral load in 37 patients with HIV infection and no previous exposure to protease inhibitor therapy.
▴ Combination therapy comprising amprenavir and other antiretroviral agents (abacavir, zidovudine, lamivudine, indinavir, saquinavir or nelfinavir) decreased viral load and increased CD4+ cell counts in patients with HIV infection. Antiviral efficacy was maintained during up to 24 weeks’ follow-up.
▴ Available data suggest that rash, headache and diarrhoea or loose stools are the most frequent adverse events associated with amprenavir therapy.
KeywordsLamivudine Zidovudine Indinavir Saquinavir Nelfinavir
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