Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fosamprenavir (FPV) with and without ritonavir (RTV) was added to the antiretroviral regimens of human immunodeficiency virus-infected subjects receiving nevirapine (NVP) to evaluate this drug interaction. Significant reductions in plasma amprenavir exposure (25 to 35%) were observed following coadministration of 1,400 mg of FPV twice a day (BID) and 200 mg of NVP BID. A regimen of 700 mg of FPV BID plus 100 mg of RTV BID may be coadministered with NVP without dose adjustment.
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PMID:Interaction between fosamprenavir, with and without ritonavir, and nevirapine in human immunodeficiency virus-infected subjects. 1694 Jan 17

Human immunodeficiency virus-infected patients have an increased risk for depression. Despite the high potential for drug-drug interactions, limited data on the combined use of antidepressants and antiretrovirals are available. Theoretically, ritonavir-boosted protease inhibitors may inhibit CYP2D6-mediated metabolism of paroxetine. We wanted to determine the effect of fosamprenavir-ritonavir on paroxetine pharmacokinetics and vice versa and to evaluate the safety of the combination. Group A started with 20 mg paroxetine every day for 10 days; after a wash-out period of 16 days, subjects received paroxetine (20 mg every day) plus fosamprenavir-ritonavir (700/100 mg twice a day) from days 28 to 37. Group B received the regimens in reverse order. On days 10 and 37, pharmacokinetic curves were recorded. Twenty-six healthy subjects (18 females, 8 males) were included. Median (range) age and weight were 44.4 (18.2 to 64.3) years and 68.8 (51.0 to 89.4) kg. Three subjects were excluded (two because of adverse events; one for nonadherence). Addition of fosamprenavir-ritonavir to paroxetine resulted in a significant decrease in paroxetine exposure: the geometric mean ratios (90% confidence intervals) of paroxetine plus fosamprenavir-ritonavir to paroxetine alone were 0.45 (0.41 to 0.49) for the area under the concentration-time curve from 0 to 24 h (AUC(0-24)), 0.49 (0.45 to 0.53) for the maximum concentration of the drug in plasma (C(max)), and 0.75 (0.71 to 0.80) for the apparent elimination half-life (t(1/2)). The free fraction of paroxetine showed a median (interquartile range) increase of 30% (18 to 42%) after the addition of fosamprenavir-ritonavir. The AUC(0-12), C(max), C(min), and t(1/2) of amprenavir and ritonavir were similar to those of historical controls. No serious adverse events occurred. Fosamprenavir-ritonavir reduced total paroxetine exposure by 55%. This is partly explained by protein displacement of paroxetine. We think that this interaction is clinically relevant and that titration to a higher dose of paroxetine may be necessary to accomplish the needed antidepressant effect.
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PMID:Interaction study of the combined use of paroxetine and fosamprenavir-ritonavir in healthy subjects. 1784 35

Rifabutin (RFB) is administered for treatment of tuberculosis and Mycobacterium avium complex infection, including use for patients coinfected with human immunodeficiency virus (HIV). Increased systemic exposure to RFB and its equipotent active metabolite, 25-O-desacetyl-RFB (dAc-RFB), has been reported during concomitant administration of CYP3A4 inhibitors, including ritonavir (RTV), lopinavir, and amprenavir (APV); therefore, a reduction in the RFB dosage is recommended when it is coadministered with these protease inhibitors. Fosamprenavir (FPV), the phosphate ester prodrug of the HIV type 1 protease inhibitor APV, is administered either with or without RTV. A randomized, open-label, two-period, two-sequence, balanced, crossover drug interaction study was conducted with 22 healthy adult subjects to compare steady-state plasma RFB pharmacokinetic parameters during concomitant administration of FPV-RTV (700/100 mg twice a day [BID]) with a 75%-reduced RFB dose (150 mg every other day [QOD]) to the standard RFB regimen (300 mg once per day [QD]) by geometric least-squares mean ratios. Relative to results with RFB (300 mg QD), coadministration of dose-adjusted RFB with FPV-RTV resulted in an unchanged RFB area under the concentration-time curve for 0 to 48 h (AUC(0-48)) and a 14% decrease in the maximum concentration of drug in plasma (C(max)), whereas the AUC(0-48) and C(max) of dAc-RFB were increased by 11- and 6-fold, respectively, resulting in a 64% increase in the total antimycobacterial AUC(0-48). Relative to historical controls, the plasma APV AUC from 0 h to the end of the dosing interval (AUC(0-tau)) and C(max) were increased approximately 35%, and the concentration at the end of the dosing interval at steady state was unchanged following coadministration of RFB with FPV-RTV. The safety profile of the combination of RFB and FPV-RTV was consistent with previously described events with RFB or FPV-RTV alone. Based on the results of this study, a reduction in the RFB dose by > or =75% (to 150 mg QOD or three times per week) is recommended when it is coadministered with FPV-RTV (700/100 mg BID).
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PMID:Pharmacokinetic interaction between fosamprenavir-ritonavir and rifabutin in healthy subjects. 1805 71

Fosamprenavir (FPV) efficacy in human immunodeficiency virus (HIV)-infected pediatric patients is still being evaluated in ongoing clinical trials. The long-term efficacy and safety of FPV boosted with ritonavir (FPV/r) was evaluated in 20 antiretroviral-naive and antiretroviral-experienced HIV-vertically infected pediatric patients. Analyses of CD4(+) T-cells, HIV-ribonucleic acid (RNA), and clinical status were performed during a median of 180 weeks. Initially, median HIV-RNA was 4.6 log(10) in naive and 4.4 log(10) in pretreated patients. Median CD4(+) T-cell was 17% and 31%, respectively. After FPV/r treatment, 18 of 20 patients achieved undetectable HIV-RNA and 4 of 20 experienced adverse events. To date, FPV/r treatment has shown sustained antiviral response and immunologic improvement in our 20 patients.
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PMID:Long-term efficacy and safety of fosamprenavir in human immunodeficiency virus-infected pediatric patients. 2016 Jun 59

Objective: Fosamprenavir, a protease inhibitor (PI) to treat human immunodeficiency virus (HIV)-infected patients, has been approved in more than 40 countries and mainly used with nucleoside reverse transcriptase inhibitors. In Japan, Lexiva tablet (fosamprenavir calcium hydrate) has been marketed since January 2005 and used in clinical practice. The safety and effectiveness of fosamprenavir in HIV-infected Japanese patients were evaluated in an observational surveillance study (OTH112334).Methods: A post-marketing surveillance study (PMS) of fosamprenavir usage in HIV-infected Japanese subjects evaluating drug safety was conducted under Good Post-marketing Study Practice from January 2005 to December 2014.Results: Of 364 patients receiving fosamprenavir, 51% received emtricitabine/tenofovir disoproxil fumarate. Adverse events whose causal relationship could not be completely ruled out (adverse drug reactions; ADRs) were reported in 43.7%; the most common were diarrhoea (10.4%), hyperlipidaemia (8.5%) and hypertriglyceridaemia (6.9%). Serious ADRs were reported in 26 patients (32 events), including 1 death attributed to hepatic failure. Most ADRs occurred within 180 days after fosamprenavir was started. ADRs were more frequent in patients with the Centers for Disease Control and Prevention category B (AIDS or lipid disorders) or in those taking fosamprenavir combined with abacavir and lamivudine. Although spontaneous bleeding has been reported in hemophiliac patients taking other PIs, in this survey, only one muscle haemorrhage case was reported in 24 hemophiliac patients.Conclusions: The results of this PMS analysis in Japan support its known safety profile and identified no new safety risks for people living with HIV/AIDS in Japan currently on, or beginning treatment with, fosamprenavir.
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PMID:Safety analysis of Lexiva tablets 700 (fosamprenavir calcium hydrate) in post-marketing surveillance in Japan. 3179 79