Indinavir Atazanavir

Protease inhibitors (amprenavir, atazanavir, indinavir, lopinavir, nelfinavir, ritonavir, saquinavir) Rifampin... 

Cross-resistance Cross-resistance among Pis has been observed. Tipranavir had less than 4-fold decreased susceptibility against 90% (94 of 105) of HIV-1 isolates resistant to amprenavir, atazanavir, indinavir, lopinavir, nelfinavir, ritonavir, or saquinavir. Tipranavir-resistant viruses that emerged in vitro had decreased susceptibility to the Pis amprenavir, atazanavir, indinavir, lopinavir, nelfinavir, and ritonavir but remained sensitive to saquinavir. 

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

Chemotherapy Cyclophosphamide, erlotlnlb, ifos-famide, paclitaxel, tamoxifen, vinblastine, vincristine HIV protease inhibitors Amprenavir, atazanavir, indinavir, nelfinavir, ritonavir, saquinavir HMG-CoA reductase inhibitors Atorvastatin, lovastatin, simvastatin... 

Ethinyl estradiol, buprenorphine ferulic acid, genistein naltrexone (low), naloxone (low), SN-38 (active metabolite of irinotecan) alizarin, quinalizarin, retigabine Bilirubin, chloropheno- Atazanavir, indinavir, xypropionic acid, chrysin, ketoconazole (AT, = 3 pM) clofibrate, 3-MC, oltipraz, phenylpropionic acid, phenobarbital, clotrimazole, rifampin, and St. John s wort. WY-14643 Response elements for AhR, CAR, GR, PPAR-a, PXR, Nrf2 (antioxidant response element) have been identified... 

PROTEASE INHIBITORS ANTIHISTAMINES-ASTEMIZOLE, CHLORPHENAMINE, TERFENADINE Possibly t adverse effects with amprenavir, atazanavir, indinavir, ritonavir (with or without lopinavir), saquinavir and tipranavir Inhibition of CYP3A4-mediated metabolism of astemizole the risk is greatest in patients who are slow CYP2D6 metabolizers because chlorphenamine and terfenadine are also metabolized by this route Avoid co-administration... 

ATAZANAVIR INDINAVIR t efficacy and t adverse effects of indinavir t adverse effects of atazanavir, e.g. hyperbilirubinaemia t bioavailability. Inhibition of metabolism via CYP3A4 by atazanavir inhibition of UDGPT by indinavir Avoid co-administration... 

L. Dickinson, L. Robinson, J. Tjia, S. Khoo, D. Back, Simultaneous determination of HIV protease inhibitors amprenavir, atazanavir, indinavir, lopinavir, nelfinavir, ritonavir and saquinavir in human plasma by LC—AdS dS, J. Chromatogr. B, 829... 

In this example, investigative studies were conducted to address an issue of unconjugated hyperbilirubinemia in human subjects observed after administration of HIV protease inhibitors indinavir and atazanavir. The proposed hypothesis for hyperbilirubinemia was inhibition of glucuronidation of bilirubin by these two drugs, a key step in the excretion of bilirubin into bile. To test this hypothesis, a panel of HIV protease inhibitors, including atazanavir, indinavir, lopinavir, nelfinavir, ritonavir, and saquinavir, were... 

Lamivudine metabolism does not involve the cytochrome P450 isoenzyme CYP3A4. Therefore it is unlikely that it will interact with drugs, such as the protease inhibitors, whieh are metabolised by this system. No pharmacokinetic interaction appears to oeeur between lamivudine and amprenavir, - atazanavir, -" indinavir, and nelfinavir. The manufacturer of lopinavir/ritonavir notes that lamivudine did not alter the pharmacokinetics of lopinavir, - and tipranavir plus low-dose ritonavir did not cause a signifieant ehange in the AUC of lamivudine. - ... 

Protease inhibitors, particularly ritonavir (see Antivirals , (p.772)), are potent inhibitors of cytochrome P450 isoenzyme CYP3A4, by which all the calcium-channel blockers are extensively metabolised. It appears that some protease inhibitors can cause a clinically relevant increase in calcium-channel blocker levels. In addition, verapamil, diltiazem and nicardipine can also inhibit CYP3A4, and might therefore theoretically reduce the metabolism of the protease inhibitors. However, the effect might depend on which is the more potent inhibitor, since, in the studies above, diltiazem did not affect atazanavir, indinavir or ritonavir levels. 

Combination of 16 ARVs seven HIV protease inhibitors (amprenavir, atazanavir, indinavir, lopinavir, nelfmavir, ritonavir, and saquinavir), seven nucleoside reverse transcriptase inhibitors (abacavir, didanosine, emtricitabine, lamivudine, stavudine, zalcitabine, and zidovudine), and two nonnucleoside reverse transcriptase inhibitors (efavirenz and nevirapine)... 

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

Drugs that should not be combined due to overlapping toxi-cities include amprenavir oral solution plus ritonavir oral solution, atazanavir plus indinavir (due to enhanced hyperbilirubinemia), and any combination of didanosine, stavudine, and zalcitabine. Emtricitabine and lamivudine should not be combined because of their similar chemical structures, and antagonism can result when lamivudine is combined with zalcitabine, or stavudine is combined with zidovudine. 

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. 

Drugs that may affect indinavir include didanosine, aldesleukin, anticonvulsants, atazanavir, nelfinavir, nevirapine, omeprazole, rifapentine, ritonavir, clarithromycin, azole antifungals, rifamycins, delavirdine, efavirenz, St. John s wort. 

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. 

NA /D, abd pain, bleeding, fevCT, T QT Interactions t Effects W7 atazanavir, clarithromycin, CT5rthromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfi-navir, ritonavir, saquinavir, telithromycin X effects W7 antacids, carbamazqjine, dexamethasone, phenobarbital, phenytoin, rifampicin, St. John s wort EMS Drug contains lactose, may cause D/abd discomfort in pts w/ lactose intolerance OD Sxs unknown symptomatic and supportive... 

Others Acetaminophen, amiodarone, carbamazepine, delavirdine, efavirenz, nevirapine, quinidine, repaglinide, sildenafil, tadalafil, trazodone, vardenafil Amiodarone, amprenavir, atazanavir, ciprofloxacin, cisapride, clarithromycin, diltiozem, erythromycin, fluconazole, fluvoxamine, grapefruit juice (in high ingestion), indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, norfloxacin, ritonavir, telithromycin, troleandomycin, verapamil, voriconazole Carbamazepine, efavirenz, glucocorticoids, macrolide antibiotics, nevirapine, phenytoin, phenobarbital, rifabutin, rifapentine, rifampin, St. John s wort... 

This class of antiretrovirals may be considered the most potent therapeutic agents for HIV to date. Protease inhibitors are used in combination regimens and combinations of reverse-transcriptase inhibitors and protease inhibitors have been proven most effective to decrease viral load and prolong survival. However, the protease inhibitors generally show poor penetration into the CNS and thus have no effect on aids dementia. The present Pis available for the treatment of HIV are indinavir, ritonavir, nel-finavir, saquinavir and (fos)amprenavir, atazanavir and lopinavir (in combination with ritonavir as ritonavir improves the bioavailability of lopinavir by inhibiting its metabolism in the liver by CYP3A). 

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... 

Atazanavir PI2 400 mg daily or 300 mg daily with ritonavir 100 daily. Adjust dose in hepatic insufficiency Take with food. Separate dosing from ddl or antacids by 1 h. Separate dosing from cimetidine and other acid-reducing agents by 12 h Nausea, vomiting, diarrhea, abdominal pain, headache, peripheral neuropathy, skin rash, indirect hyperbilirubinemia, prolonged PR and/or QTC interval See footnote 4 for contraindicated medications. Also avoid indinavir, irinotecan, and omeprazole. Avoid in severe hepatic insufficiency... 

Etravirine NNRTI 200 mg bid Take after a meal do not take on an empty stomach. Rash, nausea, diarrhea See footnote 4 for contraindicated medications. Do not administer with other NNRTIs, indinavir, atazanavir-ritonavir, fosamprenavir-ritonavir, tipranavir-ritonavir, or any unboosted PI... 

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). 

Fosamprenavir Abacavir, atazanavir, delavirdine, etravirine, indinavir, lopinavir, ritonavir, tipranavir, zidovudine Didanosine, efavirenz, nevirapine, saquinavir... 

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. 

Drugs that may inhibit cytochrome P450 metabolism of other drugs include amiodarone, androgens, atazanavir, chloramphenicol, cimetidine, ciprofloxacin, clarithromycin, cyclosporine, delavirdine, diltiazem, diphenhydramine, disulfiram, enoxacin, erythromycin, fluconazole, fluoxetine, fluvoxamine, furanocoumarins (substances in grapefruit juice), indinavir, isoniazid, itraconazole, ketoconazole, metronidazole, mexile-tine, miconazole, nefazodone, omeprazole, paroxetine, propoxyphene, quinidine, ritonavir, sulfamethizole, verapamil, voriconazole, zafirlukast, and zileuton. 

The first series of inhibitors contained structural elements related to atazanavir and indinavir and provided some highly potent compounds, the best one being 28 (Ki = 2.4 nM) [70]. 

A4/3A5 Midazolam, buspirone, felodipine, lovastatin, eletriptan, sildenafil, simvastatin, triazolam Atazanavir, clarithromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin Rifampin, carbamazepine... 

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