The relationship between plasma concentrations of nelfinavir and virologic treatment failure was investigated to determine the minimum effective concentration of nelfinavir. Plasma samples were prospectively collected from treatment-naive patients who began taking nelfinavir, 1,250 mg BID + two nucleoside reverse transcription inhibitors (NRTIs). Nelfinavir concentration ratios were calculated by dividing each individual nelfinavir level by the time-adjusted population value.
View Article and Find Full Text PDFObjective: To determine plasma concentration ratio limits (CORALS) for HIV-protease inhibitors outside of which random plasma concentrations reflect partial compliance or noncompliance. In the absence of a gold standard for measuring compliance and to avoid complex techniques, measuring plasma concentrations may be an objective and easy way to check noncompliance.
Methods: Pharmacokinetic curves after observed ingestion were recorded in patients on steady-state indinavir 800 mg TID (n = 22), ritonavir 400 mg/saquinavir 400 mg BID (n = 22, ritonavir; n = 17, saquinavir hard-gel capsules), or nelfinavir 750 mg TID (n = 4) or 1250 mg BID (n = 4).
Introduction: Adherence to highly active antiretroviral therapy is required to obtain an optimal long term virologic response rate of HIV-1-infected children. Plasma concentrations of protease inhibitors (PIs) outside the limits of the reference values indicate nonadherence to antiretroviral therapy in adults. We studied during a 2-year follow-up period routinely taken plasma protease inhibitor concentrations to assess adherence to antiretroviral therapy in HIV-1-infected children.
View Article and Find Full Text PDFBackground: Adherence to protease inhibitor-containing antiretroviral therapy is crucial, but difficult to measure.
Objective: To compare and combine various methods of measuring adherence to the strict protease inhibitor-containing regimens.
Methods: The following methods were used: medication event monitoring system (MEMS) caps (electronic monitoring), therapeutic drug monitoring, pill count, pharmacy refill data, questionnaires, diaries (for registration of food patterns and special events related to the use of MEMS), adherence assessment by the physician and clinical nurse specialist, and in-depth interviews.
Curr Opin Infect Dis
February 2002
Therapeutic drug monitoring has the promise to become a part of routine patient care in the treatment of HIV infection. It is known that plasma drug concentrations of protease inhibitors and non-nucleoside reverse transcriptase inhibitors are better predictors of antiviral response or toxicity than drug dose is. Furthermore, high interpatient variability is significant.
View Article and Find Full Text PDFObjective: This study evaluated the effect of multiple-dose efavirenz on the steady-state pharmacokinetics of the combination of indinavir (800 mg) and low-dose ritonavir (100 mg) twice a day, in which ritonavir is used to increase indinavir plasma concentrations.
Methods: Eighteen healthy male volunteers participated in this multiple-dose, 1-arm, 2-period interaction study. They took a combination of 800 mg indinavir and 100 mg ritonavir with food for 15 days.