These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Steady-state amprenavir, tenofovir, and emtricitabine pharmacokinetics before and after reducing ritonavir boosting of a fosamprenavir/tenofovir/emtricitabine regimen from 200 mg to 100 mg once daily (TELEX II). Author: Parks DA, Jennings HC, Taylor C, Pakes GE, Acosta EP. Journal: HIV Clin Trials; 2009; 10(3):160-7. PubMed ID: 19632955. Abstract: PURPOSE: Evaluate how reducing ritonavir (RTV) boosting from 200 mg to 100 mg once daily (QD) affects steady-state pharmacokinetics of components of a fosamprenavir (FPV)-based regimen. METHODS: Prospective, open-label, pharmacokinetic study in 12 HIV-infected patients stabilized on FPV/RTV 1400 mg/200 mg + tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) 300 mg/200 mg QD (TELEX II). Pharmacokinetics were assessed by noncompartmental analysis at baseline and 4 weeks after RTV reduction to 100 mg QD. RESULTS: Baseline median minimum plasma concentration (Cmin) and area under the plasma concentration-time curve over 24 hours post dose (AUC24h) were as follows: APV: 1,708 ng/mL, 84,260 h * ng/mL; tenofovir: 53 ng/mL, 2,420 h * ng/mL; FTC: 58 ng/mL, 9,190 h * ng/mL; RTV: 80 ng/mL, 10,230 h * ng/mL. Four weeks after reducing RTV, changes in Cmin and AUC24h were: APV: +26%, +0.6%; tenofovir: +77%, +30%; FTC: +188%, +13%; RTV -64%, -79%. Component plasma concentration ranges were consistent with historical values. Median APV Cmin was 14.7-fold above the protein-binding-adjusted 50% inhibitory concentration of wild-type HIV. Four weeks after RTV reduction, HIV-1 RNA levels remained <50 copies/mL in all patients, median CD4+ count increased from 465 to 495 cells/mm3, and favorable lipid changes and no adverse events were observed. CONCLUSION: Reducing RTV boosting from 200 to 100 mg QD of FPV/TDF/FTC QD conferred no detrimental effect on APV, tenofovir, FTC, or RTV pharmacokinetics and maintained virologic suppression.[Abstract] [Full Text] [Related] [New Search]