The inhibitory quotient (IQ) of human immunodeficiency virus (HIV) protease inhibitors (PIs), which is the ratio of drug concentration to viral susceptibility, is considered to be predictive of the virological response. We used several approaches to calculate the IQs of amprenavir and lopinavir in a subset of heavily pretreated patients participating in the French National Agency for AIDS Resea...

In this crossover study in 12 healthy volunteers, coadministration of amprenavir (1,200 mg; single dose) with grapefruit juice slightly reduced the maximum concentration of drug in serum (Cmax) compared to administration with water (7.11 versus 9.10 microg/ml), slightly increased the time to Cmax (1.13 versus 0.75 h), and did not affect the area under the concentration-time curve from 0 to 12 h...

The effect of hepatic impairment on fosamprenavir/ritonavir pharmacokinetics was investigated. Sixty human immunodeficiency virus type 1-infected subjects, including 13, 20, and 10 subjects with mild, moderate, and severe hepatic impairment, respectively, and a comparator group of 17 subjects with normal hepatic function, were enrolled. Subjects with normal hepatic function received fosamprenav...

OBJECTIVE The transfer of abacavir, a new nucleoside inhibitor, and amprenavir, a new protease inhibitor, used for the treatment of human immunodeficiency virus, has been studied in the ex vivo human placental model. METHODS The ex vivo human placental model used C14 antipyrine to determine the transport fraction and clearance index of these compounds at both the peak and trough serum concent...

Information about resistance profile of darunavir (DRV) is scarce in Brazil. Our objectives were to estimate the prevalence of DRV resistance mutations in patients failing protease inhibitors (PI) and to identify factors associated with having more DRV resistance mutations. All HIV-infected patients failing PI-based regimens with genotyping performed between 2007 and 2008 in a referral teaching...

BACKGROUND HIV-infected patients treated with antiretroviral medications (ARVs) develop undesirable changes in lipid and glucose metabolism that mimic the metabolic syndrome and may be proatherogenic. Antiretroviral drug levels and their interactions may contribute to these metabolic alterations. METHODS Fifty six HIV-seronegative adults were enrolled in an open-label, randomized, pharmacokin...

The high incidence of cross-resistance between human immunodeficiency virus type 1 (HIV-1) protease inhibitors (PIs) limits their sequential use. This necessitates the development of PIs with a high genetic barrier and a broad spectrum of activity against PI-resistant HIV, such as tipranavir and darunavir (TMC114). We performed a surface plasmon resonance-based kinetic study to investigate the ...

Knowledge of drug-drug interactions is crucial to HIV therapeutics. Recent reports in this area include reduced atazanavir exposure with coadministration of omeprazole or rifampin; increased hepatic toxicity with coadministration of saquinavir and rifampin; reduced buprenorphine exposure with concurrent efavirenz administration; absence of clinically significant interactions of depomedroxyproge...