Lamivudine Efavirenz

Lamivudine -I- Stavudine Lamivudine -I- Zidovudine Lamivudine + Stavudine + Efavirenz Lamivudine -I- Stavudine + Nevirapine Lamivudine -I- Zidovudine + Efavirenz Lamivudine -I- Zidovudine + Nevirapine Lamivudine -I- Zidovudine + Abacavir Tenofovir -I- Emtricitabine... 

Rifabutin 300 to 600 mg daily for 12 days did not significantly affect the pharmacokinetics of [buffered] didanosine 167 to 250 mg twice daily in 12 patients with AIDS. The steady-state pharmacokinetics of rifabutin were not affected by didanosine (buffered sachet preparation), which suggests that the buffer used in the didanosine preparation had no effect on rifabutin absorption. However, a case has been reported of a patient taking lopinavir/ritonavir, efavirenz, lamivudine and buffered didanosine who had impaired rifabutin absorption. When rifabutin was taken 30 minutes after didanosine, rifabutin levels were undetectable, but when rifabutin was taken 3 hours after didanosine, rifabutin levels were apparent. ... 

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). 

Shulman NS, Bosch RJ, MeUors JW, Albrecht MA, Katzenstein DA (2004) Genetic correlates of efavirenz hypersusceptibility. AIDS 13 1781-1785 Staszewski S, Morales-Ramirez J, Tashima KT, Rachlis A, Skiest D, Stanford J, Stryker R, Johnson P, Labriola DE, Earina D et al (1999) Efavirenz plus zidovudine and lamivudine, efavirenz plus indinavir, and indinavir plus zidovudine and lamivudine in the treatment of HIV-1 infection in adults. Study 006 Team. N Engl J Med 341 1865-1873 SteUbrink HJ (2007) Antiviral drugs in the treatment of AIDS what is in the pipeline Eur J Med Res 12 483 95... 

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... 

Efavirenz and (didanosine or abacavir or stavudine) 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. 

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. 

Drugs that may affect nelfinavir include anticonvulsants, azithromycin, azole antifungals, efavirenz, delavirdine, HMG-CoA reductase inhibitors, indinavir, interleukins, nevirapine, rifabutin, rifampin, ritonavir, saquinavir, St. John s wort. Drugs that may be affected by nelfinavir include amiodarone, antiarrhythmics (amiodarone, quinidine), azithromycin, benzodiazepines, efavirenz, ergot alkaloids, delavirdine, didanosine, fentanyl, indinavir, lamivudine methadone, nonsedating antihistamines, oral contraceptives, phenytoin, pimozide, quinidine, rifabutin, saquinavir, sildenafil, sirolimus, tacrolimus, zidovudine. 

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... 

The mechanism of action of lamivudine differs from that of efavirenz in that... 

A) Lamivudine inhibits HIV protease efavirenz inhibits reverse transcriptase. 

B) Lamivudine inhibits reverse transcriptase efavirenz inhibits HIV protease. 

C) Lamivudine is a cytosine nucleoside analogue efavirenz is an adenosine nucleotide analogue. 

D) Lamivudine binds to the active site of reverse transcriptase efavirenz binds adjacent to it. 

E) Lamivudine and efavirenz exhibit the same mechanism of action there is no difference. 

Mark C. is taking a regimen consisting of zidovudine, lamivudine, and efavirenz for the treatment of HIV infection. To help him fall asleep at night, he took a normal dose of diazepam (10 mg before bed), which he got from a friend. He then had symptoms of diazepam overdose, including grogginess and... 

L D. Lamivudine, a cytosine analogue, is a nucleoside reverse transcriptase inhibitor that acts as a competitive inhibitor of reverse transcriptase. Efavirenz is a nonnucleoside reverse transcriptase inhibitor it acts by binding to a site adjacent to the enzyme s active site. Neither drug exhibits significant activity against HIV protease. 

A. Diazepam is metabolized in the liver by CYP3A4 and CYP2C19 efavirenz inhibits both of these isozymes and is likely to increase plasma levels of diazepam. Diazepam is almost completely converted to inactive metabolites therefore, renal elimination is not much of a concern. Lamivudine may produce fatigue as a side effect but does not potentiate the depressant activity of diazepam. Zidovudine does not induce cytochrome P450 activity, and diazepam does not have to be converted to an active form for sedative activity. 

Inpatients with no prior antiretroviral therapy, a randomized trial found atazanavir equivalent to efavirenz when both were part of a 3 drug combination including zidovudine and lamivudine another trial found atazanavir equivalent to nelfinavir when both were part of a 3 drug combination including lamivudine and stavudine... 

Combikit of 2 tablet of Stavudine + Lamivudine each 1 tablet of Efavirenz... 

Gallant JE, DeJesus E, Arribas JR, Pozniak AL, et al. 2006. Tenofovir DF, Emtricitabine and Efavireuz vs. Zidovudine, Lamivudine and Efavirenz for HIV. NEJM. 354 251-260. 

Sataszewski S, Morales-Ramirez J, Tashima KT, Rachlis A, et al. 1999. Efavirenz plus zidovudine and lamivudine, efavirenz plus indinavir, and indinavir plus zidovudine and lamivudine in the treatment of HIV-1 infection in adults. Study 006 team. NEJM. 341 1865-1873. 

The effects of the protease inhibitor indinavir and the NNRTI efavirenz on lipid concentrations have been compared in a large comparative randomized study (154). Each of the two comparison drugs were used in one arm (with a zidovudine + lamivudine backbone) and the combination of the two drugs in a third arm. Zidovudine and lamivudine did not play a role in the lipid changes. However, both of the comparison drugs significantly increased cholesterol concentrations. 

At the present time, there are at least 14 compounds that have been formally approved for the treatment of human immunodeficiency virus (HIV) infections. There are six nucleoside reverse transcriptase inhibitors (NRTIs) that, after their intracellular conversion to the 5 -triphosphate form, are able to interfere as competitive inhibitors of the normal substrates (dNTPs). These are zidovudine (AZT), didanosine (ddl), zalcitabine (ddC), stavudine (d4T), lamivudine (3TC), and abacavir (ABC). There are three nonnucleoside reverse transcriptase inhibitors (NNRTIs) — nevirapine, delavirdine, and efavirenz — that, as such, directly interact with the reverse transcriptase at a nonsubstrate binding, allosteric site. There are five HIV protease inhibitors (Pis saquinavir, ritonavir, indinavir, nelfinavir, and amprenavir) that block the cleavage of precursor to mature HIV proteins, thus impairing the infectivity of the virus particles produced in the presence of these inhibitors. 

Mayers D, Jemesk J, Eyster E, et al. In A double-blind, placebo-controlled study to assess the safety, tolerability and antiretroviral activity of efavirenz (EFV DMP 266) in combination with open-label zidovudine (ZDV) and lamivudine (3TC) in HIV infected patients (DMP 266-004)38th Interscience Conference on Antimicrobial Agents and Chemotherapy (San Diego). Washington DC American Society for Microbiology, 1998 22340. 

Based on data from clinical trials, either an NNRTI-based or Pl-based regimen should be offered to andretroviral-naiVe patients for whom therapy is indicated. The preferred NNRTI-based regimen includes efavirenz and tw o NNRTIs either lamivudine or emh icitabine plus zidovudine or tenofovir. 

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