Tenofovir Atazanavir

ATAZANAVIR TENOFOVIR i efficacy of atazanavir Uncertain l plasma levels of atazanavir Use with caution and consider using in combination with ritonavir... 

Zidovudine Didanosine Stavudine Lamivudine Abacavir Tenofovir Emtricitabine Nevirapine Efavirenz TMC125 Saquinavir Indinavir Lopinavir Fosamprenavir Atazanavir Tipranavir Darunavir Raltegravir Elvitegravir Enluvirtide Maraviroc Vicriviroc Bevirimat... 

Tenofovir + Emtricitabine Zidovudine + Lamivudine Abacavir + Lamivudine Efavirenz or Nevirapine Lopinavir/r or Atazanavir/r or Eosamprenavir/r or Saquinavir/r... 

Atazanavir or fosamprenavir or nelfinavir or saquinavir/ ritonavir, and zidovudine or stavudine or tenofovir or abacavir or didanosine, and lamivudine or emtricitabine... 

TC, lamivudine ABC, abacavir APV, amprenavir AST, aspartate aminotransferase ALT, alanine aminotransferase ATV, atazanavir CBC, complete blood cell count D/C, discontinue ddl, didano-sine d4T, stavudine EFV, efavirenz FTC, emtricitabine P1BV, hepatitis B virus F1CV, hepatitis C vims HIV, human immunodeficiency virus IDV, indinavir IV, intravenous LFT, liver function tests LPV/r, lopinavir + ritonavir NNRTI, nonnucleoside reverse transcriptase inhibitor NRTI, nucleoside reverse transcriptase inhibitor NVP, nevirapine PI, protease inhibitor PT, prothrombin time T.bili, total bilirubin TDF, tenofovir disoproxiI fumarate TPV, tipranavir ULN, upper limit of normal ZDV, zidovudine. 

Your patient begins treatment with atazanavir 300 mg PO once daily, ritonavir 100 mg PO once daily, tenofovir 300 mg PO once daily, and lamivudine 300 mg PO once daily. He initially does well on this regimen, but after about 3 months, he has difficulty taking his medications at the same time every day due to his busy schedule. Because of his job, he relocated to Alabama, and has not been seen in your clinic for 2 years. He returns today to see you in clinic and complains of feeling tired, but otherwise no specific complaints. 

Lopinavir/ritonavir or atazanavir/ritonavir and (zidovudine or fosamprenavir/ritonavir or tenofovir) and (lamivudine or emtricitabine). 

Tenofovir disoproxil fumarate - It is recommended that atazanavir 300 mg be given with ritonavir 100 mg and tenofovir 300 mg (all as a single daily dose with food). Atazanavir without ritonavir should not be coadministered with tenofovir. 

Drugs that may be affected by atazanavir include the following antiarrhythmics, atenolol, benzodiazepines, calcium channel blockers, cisapride, clarithromycin, ergot derivatives, HMG-CoA reductase inhibitors, immunosuppressants, indinavir, irinotecan, itraconazole, ketoconazole, oral contraceptives, PDE5 inhibitors, pimozide, rifabutin, saquinavir, tenofovir, tricyclic antidepressants, voriconazole, warfarin. 

Drugs that may affect atazanavir include the following antacids and buffered medications, clarithromycin, didanosine (buffered formulation only), efavirenz, H2-receptor antagonists, indinavir, itraconazole, ketoconazole, nevirapine, proton pump inhibitors, rifampin, ritonavir, St. John s wort, tenofovir, voriconazole. 

Drugs that may affect tenofovir include atazanavir, indinavir, and lopinavir/ritonavir. Drugs that may be affected by tenofovir include abacavir, atazanavir, didanosine... 

TC Lamivudine ABC Abacavir d4T Stavudine ddC Zalcitabine ddl Didanosine TDF Tenofovir ZDV Zidovudine, also abbreviated as AZT FTC Emtricitabine NVP Nevirapine DLV Delavirdine EFV Efavirenz RTV, r Ritonavir Pl/r Ritonavir boosted protease inhibitor SQV Saquinavir IDV Indinavir LPV Lopinavir NEV Nelfinavir APV Amprenavir ATV Atazanavir DRV Darunavir... 

HIV-1 infection (concurrent therapy with tenofovir) PO 300 mg atazanavir and 100 mg... 

Tenofovir NRTI1 300 mg qd3 Take with food. Nausea, diarrhea, vomiting, flatulence, headache, renal insufficiency Avoid concurrent atazanavir, probenecid, didanosine... 

The buffer in didanosine tablets and powder interferes with absorption of indinavir, delavirdine, atazanavir, dapsone, itraconazole, and fluoroquinolone agents therefore, administration should be separated in time. Serum levels of didanosine are increased when -administered with tenofovir or ganciclovir, and are decreased by atazanavir, delavirdine, ritonavir, tipranavir, and methadone (Table 49-4). 

Atazanavir Ritonavir Fosamprenavir, didanosine, efavirenz, etravirine, stavudine, tenofovir... 

Didanosine Tenofovir, ganciclovir Atazanavir, delavirdine, ritonavir, tipranavir... 

As an inhibitor of CYP3A4 and CYP2C9, the potential for drug-drug interactions with atazanavir is great (Tables 49-3 and 49-4). Atazanavir AUC is reduced by 76% when combined with omeprazole thus, the combination is to be avoided. In addition, co-administration of atazanavir with other drugs that inhibit UGT1A1, such as indinavir and irinotecan, is contraindicated because of enhanced toxicity. Tenofovir and efavirenz should not be -administered with atazanavir unless ritonavir is added to boost levels. 

A combination of tenofovir and didanosine is not recommended since tenofovir increases the AUC of didanosine. It also reduces the AUC of atazanavir. 

Preferred regimen Efivarenz Atazanavir + ritonavir Fosamprenavir + ritonavir Lopinavir/ ritonavir Tenofovir/ emtricitabine Zidovudine/ lamivudine... 

Taltobulin, 11 Tamibarotene, 76 Tandutinib, 183 Tanomastat, 47 Tezacitabine, 131 Tipifamib, 172 Topixantrone, 227 Troxacitabine, 131 Vandetanib, 181 Antipsoriatic Ecalcidine, 38 Antiviral Amdoxovir, 199 Amprenavir, 4 Aplaviroc, 134 Atazanavir, 7 Capravirine, 95 Clevudine, 130 Daninavir, 5 Efavirenz, 177 Emivirine, 123 Emtricitabine, 132 Etravirine, 123 Fosamprenavir, 6 Lopinavir, 7 Maraviroc, 107 Maribavir, 158 Omaciclovir, 199 Oseltamivir, 25 Peramavir, 53 Rupinavir, 9 Tenofovir, 197 Tiprinavir, 120 Anxiolytic Sunepitron, 209 Apetite Supressant Rimonabant, 99 Cardiotonic Naxifylline, 203 Torborinone, 172 Collagenase Inhibitor Cipemastat, 99 Diuretic Lixivaptan, 222 Tolvaptan, 186 Elastase Inhibitor Sivelstat, 54... 

Although tenofovir is not known to induce CYPs, it has been reported to reduce the atazanavir AUC by approximately 26%. In addition, low-dose ritonavir (100 mg twice daily) increases the tenofovir AUC by 34%, and atazanavir increases the tenofovir AUC by 25%. The mechanism of these interactions is unknown. 

ABBREVIATIONS EFV, efavirenz 3TC, lamivudine AZT, zidovudine TDF, tenofovir disoproxil fumarate d4T, stavudine LPV/r, lopinavir/ritonavir coformulation FTC, emtricitabine NVP, nevirapine ddl, didanosine ATV, atazanavir fosAPV, fosamprenavir RTV, ritonavir IDV, indinavir NFV, nelfinavir SQV, saquinavir. 

Atazanavir/ritonavir, darunavir/ritonavir and lopinavir/ritonavir modestly increased the levels of tenofovir, and there is at least one case report of nephrotoxicity with the combination of tenofovir, didanosine, and lopinavir/ritonavir. Saquinavir/ritonavir, ti-pranavir/ritonavir, and probably also fosamprenavir/ritonavir, have little effect on tenofovir levels. Tenofovir modestly decreased atazanavir levels, and this was minimised when ritonavir was also given. Tenofovir had no important effect on ritonavir-boosted darunavir, lopinavir, and tipranavir levels, and modestly increased those of ritonavir-boosted saquinavir in one of two studies. Indinavir and nelfinavir do not interact pharmacokineti-cally with tenofovir. 

The AUC of atazanavir was decreased by 25%, and the trough level by 40% when atazanavir 400 mg daily was given with tenofovir disoproxil fumarate 300 mg daily, and the AUC of tenofovir was increased by 24%. Similar results were seen when administration was separated by 12 hours. ... 

When atazanavir 300 mg once daily was given with ritonavir 100 mg once daily (as a pharmacokinetic booster), tenofovir disoproxil fumarate 300 mg once daily reduced the AUC of atazanavir by a similar amount (25%), but had less effect on the trough level (23% reduction), when compared with atazanavir/ritonavir alone. Similarly, the pharmacokinetics of atazanavir/ritonavir did not differ significantly between patients taking tenofovir and those not. Combined use increased the tenofovir AUC by 37% and the minimum level by 29%. - ... 

The decrease in atazanavir levels with tenofovir is not of clinical importance if ritonavir is also used, and this combination has been used successfully as part of antiretroviral therapy in clinical studies. Unboosted atazanavir should be used with caution or not given with tenofovir because of the potential for reduced etficacy and development of resistance. Ritonavir-boosted darunavir and lopinavir levels were not significantly affected by tenofovir, amprenavir levels were also unaffected following boosted fosamprenavir administration, and the increase in ritonavir-boosted saquinavir levels are not likely to be clinically relevant. The slight interaction between tenofovir and tipranavir/ritonavir is unlikely to be clinically relevant. There is no clinically relevant interaction between nelfinavir or indinavir and tenofovir. 

Hentig NV, Haberl A, Lutz T, Klauke S, Kurowski M, Harder S, Staszewski S. Concomitant intake of tenofovir disoproxil fumarate (TDF) does not impair plasma exposure of ritonavir (RTV) boosted atazanavir (ATV) in HIV-1 infected adults. Clin Pharmacol Ther (2005) 77, PI 8. 

Hodder S, Bristol-Myers Squibb Company, Klein R, Struble K, FDA. Letter to health care providers. Re Important new pharmacokinetic data for REYATAZ (atazanavir sulfate) in combination with Viread (tenofovir disoproxil fumarate). August 8, 2003. Available at http //www.fda.gOv/oashi/aids/listserve/listserve2003.html (accessed 21/08/07). 

Gallant JE, Koenig E, Andrade-Villanueva J, Chetchotisakd P, Dejesus E, Antunes F, et al. Cobidstat versus ritonavir as a pharmacoenhancer of atazanavir plus emtricitabine/tenofovir disoproxil fumarate in treatment-naive HIV type 1-infected patients week 48 results. J Infect Dis... 

EUon R, Cohen C, Gathe J, ShaUt P, Hawkins T, Liu HC, et al. Phase 2 study of cobicistat versus ritonavir each with once-daily atazanavir and fixed-dose emtricitabine/tenofovir df in the initial treatment of HIV infection. AIDS 2011 25(15) 1881-6. 

Rockstroh JK, Dejesus E, Henry K, Molina JM, Gathe J, Ramanathan S, et al. A randomized, double-blind comparison of cofarmulated elvite-gravir/cobicistat/emtricitabine/tenofovir DF vs ritonavir-boosted atazanavir plus coformulated emtricitabine and tenofovir DF for initial treatment of HIV-1 infection analysis of week 96 results. J Acquir Immune Defic Syndr 2013 62(5) 483-6. 

Young J, Schafer J, Fux GA, Furrer H, Bernasconi E, Vemazza P, et al. Swiss HIV Cohort Study. Renal function in patients with HIV starting therapy with tenofovir and either efavirenx, lopinavir or atazanavir. AIDS 2012 26(5) 567-75. 

Calza L, Trapani F, Salvadori C, MagistreUi E, Manfredi R, ColangeK V, et al. Incidence of renal toxicity in HIV-infected, antiretroviral-naive patients starting tenofovir/emtricitabine associated with efavirenz, atazanavir/ritonavir, or lopinavir/ritonavir. Scand J Infect Dis... 

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