Lamivudine Tenofovir

LAMIVUDINE, TENOFOVIR, ZALCITABINE FOSCARNET SODIUM t adverse effects with tenofovir and possibly lamivudine and zalcitabine Uncertain possibly additive toxicity via competition for renal excretion Avoid if possible otherwise monitor FBC and renal function weekly... 

Tenofovir in its prodrug form tenofovir, disoproxil fumarate (TDF), is indicated in the treatment of HIV infections (AIDS). It is administered as a single oral dose of 300 mg per day. When combined with emtricitabine and efavirenz, TDF has proven to be more efhcacious than the standard combination therapy of combivir (azidothymidine plus lamivudine) and efavirenz (Gallant et al. 2006) and less prone to cause adverse side effects (Pozniak et al. 2006 De Clercq 2007b). 

All the nucleoside (and nucleotide) analogues that have entered the clinic for the treatment of HBV infections (i.e., nucleoside analogues lamivudine, entecavir, tel-bivudine nucleotide analogues adefovir and tenofovir) are fairly well tolerated without side effects that would preclude their long-term usage. The nucleoside analogues in (pre)clinical development for the treatment of HCV infections are not yet sufficiently advanced to assess their tolerability and/or safety. 

In addition to the NRTI lamivudine (3TC) and the NtRTI adefovir dipivoxU and tenofovir disoproxil fumarate (which has been recently licensed for the treatment of chronic hepatitis B), two other nucleoside analogues, that is, entecavir and L-dT (tel-bivudine) (Fig.4aa), have been licensed for the treatment of HBV infections. Two other compounds 3 -Val-L-dC (valtorcitabine) and L-FMAU (clevudine) (Fig. 4aa) are in clinical development for the treatment of HBV infections, and yet two other compounds, that is, racivir and elvucitabine (Fig. 3), yield potential for the treatment of both HBV and HIV infections. 

Landman R, Descamps D, Peytavin G, Trylesinski A, Katlama C, Girard PM, Bonnet B, Yeni P, Bentata M, Michelet C, Benalycherif A, Brun VF, Miller MD, Flandre P (2005) Early virologic failure and rescue therapy of tenofovir, abacavir, and lamivudine for initial treatment of HlV-1 infection TONUS study, HIV Clin Trials 6 291-301... 

Lanier ER, Hazen R, Ross L, Freeman A, Harvey R (2005) Lack of antagonism between abacavir, lamivudine, and tenofovir against wild-type and drug-resistant HlV-1, J Acquir Immune Defic Syndr 39 519-522... 

Add adefovir or tenofovir Add lamivudine or telbivudine Switch to or add adefovir or tenofovir Add adefovir or tenofovir... 

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... 

Triple NRTI therapy is recommended only when a first-line or alternative first-line therapy with either an NNRTI-based or Pi-based regimen cannot be used. Abacavir plus zidovudine plus lamivudine is the only regimen approved by the DHHS. The following triple nucleoside therapy combinations have shown poor or limited efficacy, and should be avoided abacavir plus tenofovir plus lamivudine (or emtricitabine), and didanosine plus tenofovir plus 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). 

Current recommendations for treating HIV infection advocate a minimum of three antiretroviral agents. The typical regimen consists of two NtRTIs and either a ritonavir-boosted PI or NNRTI. The dual NtRTI backbone should include tenofovir plus emtricitabine (coformulated as Truvada) or zidovudine plus lamivudine (coformulated as Combivir). Abacavir plus lamivudine is an alternative. Recommended initial NtRTIs include atazana-vir-ritonavir, lopinavir-ritonavir, or fosamprenavir-ritonavir. Efavirenz is the recommended NNRTI except for women who plan to become pregnant or who do not have adequate contraception. 

In treatment-naive patients, consider emtricitabine/tenofovir disoproxil fumarate as an alternative to the combination of tenofovir disoproxil fumarate plus lamivudine (3TC) for those patients who might benefit from a once-daily regimen. In treatment-experienced patients, guide the use of emtricitabine/tenofovir disoproxil fumarate by laboratory testing and treatment history. 

The present NRTIs available for the treatment of HIV are zidovudine (azidothymidine, AZT), stavu-dine (d4T), didanosine (ddl), lamivudine (3TC), dideoxycytidine (ddC, zalcitabine) and abacavir, emtricitabine and tenofovir disoproxil. Combination formulations are abcavir combined with zidovudine and lamivudine and the abacavir-lamivudine combination. 

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... 

Zidovudine (ZDV or AZT) is a nucleoside reverse transcriptase inhibitor (NRTI) and it was the first anti-HIV agent to be introduced. Other NRTIs include stavudine (d4T), lamivudine (3TC), didano-sine (ddl), abacavir (ABC) and zalcitabine (ddC). Recent additions to this class are emtricitabine (FTC) which has a molecular structure similar to 3TC and tenofovir (TDF) a nucleotide reverse transcriptase inhibitor. 

Several anti-HBV agents have anti-HIV activity as well, including lamivudine, adefovir dipivoxil, and tenofovir. Emtricitabine, an antiretroviral NRTI, is under clinical evaluation for HBV treatment. Because NRTI agents may be used in patients co-infected with HBV and HIV, it is important to note that acute exacerbation of hepatitis may occur upon discontinuation or interruption of these agents. 

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