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 56,091 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 36-year-old homosexual man with 6 months of visual symptoms and headaches had right homonymous hemianopia, mild new learning impairment, and alexia with agraphia. The initial brain magnetic resonance imaging (MRI) scan was reported consistent with left occipital infarction. Subsequent MRI demonstrated abnormal demyelination in subcortical white matter and deep parieto-occipital white matter bilaterally, but primarily left. Human immunodeficiency virus testing and cerebrospinal fluid polymerase chain reaction for JC virus DNA were both positive, consistent with progressive multifocal leukoencephalopathy (PML) with AIDS. His clinical status steadily deteriorated, and MRI white matter abnormalities worsened despite high-dose antiretroviral therapy. After the antiretroviral regimen was intensified by the addition of a protease inhibitor, rapid clinical and radiographic improvement occurred with subsequent MRI studies revealing only residual left parieto-occipital encephalomalacia. PML in AIDS patients has been associated with a nearly uniformly poor prognosis until recent reports of improved outcomes after highly active antiretroviral therapy. This patient with PML and AIDS similarly showed a robust clinical and MRI response to intensive antiretroviral combination therapy, which has been maintained for more than 3 years.
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PMID:Clinical and magnetic resonance imaging regression of progressive multifocal leukoencephalopathy in an AIDS patient after intensive antiretroviral therapy. 1146 8

A substantial body of evidence provides support (but not definitive proof of efficacy) for the use of antiretroviral agents as postexposure prophylaxis for occupational exposures to HIV in the healthcare workplace. Despite the lack of definitive evidence of the efficacy of these agents in this setting, over the past decade this intervention has become the standard of care for healthcare workers who sustain occupational exposures to HIV. Administration of these agents--even for a relatively short 28-day postexposure course--is often fraught with difficulty. All of the agents currently used for postexposure prophylaxis regimens have substantial adverse effects, and significant adverse effects occur in more than two-thirds of individuals electing prophylaxis. This manuscript reiterates current US Federal Government guidelines for the administration of postexposure prophylaxis, specifically noting that zidovudine plus lamivudine (with or without a protease inhibitor) remains the recommended regimen. The paper summarises the significant toxicities associated with nucleoside reverse transcriptase inhibitors (primarily nausea, vomiting, diarrhoea and bone marrow suppression), non-nucleoside reverse transcriptase inhibitors (rash, fever, gastrointestinal symptoms and hepatitis, including hepatic decompensation necessitating liver transplantation) and protease inhibitors (nausea, vomiting, diarrhoea, abdominal pain, hyperglycaemia, hyperlipidaemia, headache and anorexia). As a class, the antiretroviral agents have an extraordinary number of drug interactions. The non-nucleoside reverse transcriptase inhibitors and the protease inhibitors are metabolised through the cytochrome P450 pathway, and the effects of concomitant administration of protease inhibitors with other agents in the same class are discussed, as well as the effects of concomitant administration of protease inhibitors with non-nucleoside agents. The potential for numerous and medically risky drug interactions emphasises the importance of planning antiretroviral prophylaxis in consultation with practitioners or clinical pharmacists who are skilled in the use of these agents and knowledgeable about the potential for significant drug interactions that could either reduce the benefit of prophylaxis or increase the potential for toxicity. Another common problem encountered by individuals managing postexposure prophylaxis programmes relates to the administration of chemoprophylaxis to a pregnant healthcare worker who has sustained an occupational exposure to HIV. We address what is known about the potential for toxicity and emphasise the recently published warning concerning the deaths of pregnant women and their offspring from lactic acidosis while receiving regimens containing stavudine and didanosine.
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PMID:Tolerability of postexposure antiretroviral prophylaxis for occupational exposures to HIV. 1148 Apr 91

We assessed the impact of an efavirenz-containing regimen versus a protease inhibitor-containing regimen on quality of life, emotional status, and adherence of HIV-1-infected patients. In addition, we sought to define the adverse events associated with these treatments, with a special focus on central nervous system disorders in the efavirenz treatment group. This prospective, randomized, two-arm, controlled study included 100 patients for whom initial treatment with a protease inhibitor-containing regimen failed. Patients were randomized to start treatment with two nucleoside retrotranscriptase inhibitors plus efavirenz (group 1; 51 patients) or two nucleoside retrotranscriptase inhibitors plus one or more new protease inhibitors (group 2; 49 patients). Quality of life was assessed by a five-point item adapted from the HIV questionnaire of the Medical Outcomes Study, emotional status was evaluated by the Profile of Mood State questionnaire, and patients self-reported adherence. Data were analyzed by both an as-treated method and an intention-to-treat-last observation carried forward method. Patients in group 1 reported the following findings at week 4: dizziness (66%), abnormal dreaming (48%), light-headedness (37%), and difficulty sleeping (35%). At week 24, dizziness (13%; p <.001), abnormal dreaming (18%; p =.002), light-headedness (13%; p =.01), difficulty sleeping (7%; p =.001), and nervousness (13%; p =.01) decreased in these patients. Irritability, abnormal dreaming, and nervousness persisted at week 48 in 13%, 10%, and 8% of group 1 patients, respectively. Patients in group 2 reported the following findings at week 4: light-headedness (8%), dizziness (5%), difficulty sleeping (4%), nervousness (4%), and headaches (3%). Patients in group 2 reported the following findings at week 48: difficulty sleeping (4%), nervousness (3%), headaches (3%), and light-headedness (2%). In group 1, quality of life (p <.001) and emotional status (week 48; p =.004) improved, both of which were better than those in group 2 (p =.001). Both groups maintained high levels of medication adherence, and no significant differences in the number of patients who had viral loads of <200 copies/mL at week 48 were found (78% of group 1 patients vs. 85% of group 2 patients; p = not significant). At week 48, the mean CD4 cell count +/- SD was 497 +/- 224/mm3 in group 1 and 539 +/- 298/mm3 in group 2 (p = not significant). Despite similar immunologic and virologic outcomes, a second-line efavirenz-containing regimen improved quality of life of HIV-1-infected patients compared with a second-line protease inhibitor-containing regimen. However, close follow-up of patients receiving treatment with efavirenz-based regimens is recommended, especially for those with previous emotional disturbances due to central nervous system disorders in the short term and those with persistence of a low percentage of these disorders in the long term.
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PMID:Quality of life, emotional status, and adherence of HIV-1-infected patients treated with efavirenz versus protease inhibitor-containing regimens. 1187 73

Atazanavir is the first once-daily protease inhibitor for the treatment of human immunodeficiency virus type 1 infection and should be used only in combination therapy, as part of a highly active antiretroviral therapy (HAART) regimen. In addition to being the most potent protease inhibitor in vitro, atazanavir has a distinct cross-resistance profile that does not confer resistance to other protease inhibitors. However, resistance to other protease inhibitors often confers clinically relevant resistance to atazanavir. Currently, atazanavir is not a preferred protease inhibitor for initial HAART regimens. In treatment-naive patients, atazanavir can be given as 400 mg/day. However, atazanavir should be pharmacologically boosted with ritonavir in treatment-experienced patients or when coadministered with either tenofovir or efavirenz. Patients who receive atazanavir experience similar rates of adverse events compared with patients receiving comparator regimens. An exception is an increased risk of asymptomatic hyperbilirubinemia, which is due to competitive inhibition of uridine diphosphate-glucuronosyltransferase 1A1. Although hyperbilirubinemia is a common adverse drug reaction of atazanavir therapy (22-47%), fewer than 2% of patients discontinue atazanavir therapy because of this adverse effect. Common adverse effects reported with atazanavir include infection, nausea, vomiting, diarrhea, abdominal pain, headache, peripheral neuropathy, and rash. Of significance, fewer abnormalities have been observed in plasma lipid profiles in patients treated with atazanavir compared with other protease inhibitor-containing regimens. As with other protease inhibitors, atazanavir is also a substrate and moderate inhibitor of the cytochrome P450 (CYP) system, in particular CYP3A4 and CYP2C9. Clinically significant drug interactions include (but are not limited to) antacids, proton pump inhibitors, histamine type 2 receptor antagonists, tenofovir, diltiazem, irinotecan, simvastatin, lovastatin, St. John's wort, and warfarin. We conclude that atazanavir is a distinctively characteristic protease inhibitor owing to its in vitro potency, once-daily dosing, distinct initial resistance pattern, and infrequent association with metabolic abnormalities.
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PMID:Atazanavir for the treatment of human immunodeficiency virus infection. 1558 41

(1) The current first-line treatment for HIV infection is a combination of at least two nucleoside (or nucleotide) inhibitors of HIV reverse transcriptase, and one non nucleoside inhibitor or at least one HIV protease inhibitor. (2) Emtricitabine is the eighth nucleoside/nucleotide inhibitor to be marketed in France. It has a similar chemical structure to lamivudine. (3) Evaluation of emtricitabine use in adults contains data from four comparative trials, two in treatment-naive patients and two in patients who were already receiving a virologically effective treatment. Emtricitabine combination therapy was no more effective than lamivudine combination therapy on either viral load or the CD4+ lymphocyte count. (4) Only non comparative trials are available in children. (5) In clinical trials, the adverse effects of emtricitabine were similar to those of lamivudine, including headache, pain, fatigue, fever, abdominal pain, nausea, vomiting, and diarrhea. (6) Viral strains resistant to emtricitabine are also resistant to lamivudine, and vice versa. (7) Emtricitabine, like other nucleoside inhibitors (lamivudine, didanosine, tenofovir), can be taken once a day by mouth. (8) In practice, emtricitabine is indistinguishable from lamivudine and does not offer any advance for patients living with HIV/AIDS.
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PMID:Emtricitabine: new preparation. An antiretroviral very similar to lamivudine. 1587 41

Brecanavir (BCV, 640385) is a novel, potent protease inhibitor (PI) with low nanomolar 50% inhibitory concentrations against PI-resistant human immunodeficiency virus (HIV) in vitro. This phase I, double-blind, randomized, placebo-controlled, two-part single-dose study (first time with humans) was conducted to determine the safety, tolerability, and pharmacokinetics of BCV administered at 10 mg/ml in a tocopherol-polyethylene glycol succinate-polyethylene glycol 400-ethanol 50:40:10 solution. In part 1 of the study, single oral doses of BCV ranged from 25 mg to 800 mg. In part 2, single oral doses of BCV ranged from 10 mg to 300 mg and were coadministered with 100-mg oral ritonavir (RTV) soft gel capsules. Single doses of BCV and BCV/RTV were generally well tolerated. There were no severe adverse events (SAEs), and no subject was withdrawn due to BCV. The most commonly reported drug-related AEs during both parts of the study combined were gastrointestinal disturbances (similar to placebo) and headache. BCV was readily absorbed following oral administration with mean times to maximum concentration from >1 h to 2.5 h in part 1 and from 1.5 h to 3 h in part 2. Administration of BCV without RTV resulted in BCV exposures predicted to be insufficient to inhibit PI-resistant virus based on in vitro data. Coadministration of 300 mg BCV with 100 mg RTV, however, significantly increased the plasma BCV area under the concentration-time curve and maximum concentration 26-fold and 11-fold, respectively, achieving BCV concentrations predicted to inhibit PI-resistant HIV.
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PMID:Single-dose safety and pharmacokinetics of brecanavir, a novel human immunodeficiency virus protease inhibitor. 1672 84

Brecanavir (BCV) is a novel, potent protease inhibitor in development for the treatment of human immunodeficiency virus (HIV-1) infection with low nM in vitro 50% inhibitory concentrations (IC50s) against many multiprotease inhibitor resistant viruses. This study was a double-blind, randomized, placebo-controlled repeat-dose escalation to evaluate the safety, tolerability, and pharmacokinetics of BCV, with or without ritonavir (RTV), in 68 healthy subjects. Seven sequential cohorts (n=10) received BCV (50 to 600 mg) in combination with 100 mg RTV (every 12 h [q12h] or q24h) or alone at 800 mg q12h for 15 days. BCV alone or in combination with RTV was well tolerated, with no serious adverse events reported. The most common drug-related adverse event was headache. BCV was readily absorbed with median time to maximum concentration of drug in serum values ranging from 2.5 to 5.0 h postdose following single- and repeat-dose administration of BCV alone and BCV with RTV 100 mg. Geometric mean BCV accumulation ratios ranged from 1.4 to 1.56 following BCV-RTV q24h regimens and from 1.84 to 4.93 following BCV q12h regimens. BCV steady state was generally achieved by day 13 in all groups. All day 15 BCV-RTV trough concentration values in q12h regimens reached or surpassed the estimated protein-binding corrected in vitro IC50 target BCV concentration of 28 ng/ml for highly resistant isolates. The pharmacokinetic and safety profile of BCV-RTV supports continued investigation in HIV-1-infected subjects.
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PMID:Safety and pharmacokinetics of brecanavir, a novel human immunodeficiency virus type 1 protease inhibitor, following repeat administration with and without ritonavir in healthy adult subjects. 1726 26

The efficacy, safety, and pharmacokinetics of three doses of tipranavir/ritonavir (TPV/r) in highly treatment-experienced human immunodeficiency virus (HIV)-1-infected patients with protease inhibitor (PI)-resistant isolates were evaluated. A 24-week multicenter, double-blind, randomized, dose-finding trial was conducted. All patients were three-drug class experienced and had taken at least two PI-based regimens. All had at least one primary PI mutation and had plasma HIV-RNA > 1000 copies/ml. Patients remained on their background non-PI antiretroviral medications for the first 14 days. After this 14-day period of functional TPV/r monotherapy, the background antiretroviral medications were optimized based on treatment history and the screening genotype. A total of 216 patients were randomized. All groups [TPV/r 500 mg/100 mg (n = 73), 500 mg/200 mg (n = 72), and 750 mg/200 mg (n = 71) twice daily] achieved an approximate 1 log10 reduction in the median HIV-RNA at week 2. A significant reduction was sustained through 24 weeks in the TPV/r 500 mg/200 mg and 750 mg/200 mg groups. The 500 mg/200 mg dose achieved optimal median TPV trough concentrations and lower interpatient variability. The most frequently reported adverse events (AEs) were diarrhea, nausea, vomiting, fatigue, and headache. The TPV/r 750 mg/200 mg group had the highest rate of grade 3 or 4 laboratory abnormalities and study discontinuations due to AEs. All doses of TPV/r tested in this study were associated with HIV-1 viral load reductions through 24 weeks. The 500 mg/200 mg dose achieved the best efficacy, safety, and pharmacokinetic profile in this highly treatment-experienced population and was selected for the pivotal phase 3 studies.
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PMID:Efficacy and safety of three doses of tipranavir boosted with ritonavir in treatment-experienced HIV type-1 infected patients. 1726 50

A 14-year-old female with perinatally acquired HIV on boosted protease inhibitor (PI) therapy with atazanavir and ritonavir rapidly developed cushingoid features with excessive weight gain and moon facies within 2 weeks of receiving inhaled fluticasone/salmeterol for asthma treatment. Soon after discontinuing PIs and inhaled steroid, she required hospitalization for dyspnea, headache, muscle weakness, and extreme fatigue requiring hydrocortisone replacement therapy for presumed adrenal insufficiency. Cushing syndrome and adrenal suppression were very likely caused by elevated steroid systemic concentrations resulting from the cytochrome p450 interaction between the protease inhibitors and fluticasone. The Naranjo probability scale score of 5 suggests that the event was probably drug related. This is the first case report of fluticasone and PI-induced Cushing syndrome and adrenal suppression in a pediatric patient without a history of recent or concomitant treatment with systemic steroid therapy. Additionally, this case is unique as it is the most rapid (<2 weeks) presentation documented, thus far. Health care professionals should be conscious of this important drug-drug interaction in HIV-infected children and adolescents and be aware that rapid onset of hypercortisolism and adrenal suppression are possible.
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PMID:Cushing syndrome and severe adrenal suppression caused by fluticasone and protease inhibitor combination in an HIV-infected adolescent. 1759 45

OBJECTIVES: Rifampin is a potent inducer of the cytochrome P450 3A4 isoenzyme (CYP3A4) that metabolizes most protease inhibitor (PI) antiretrovirals. This study was designed to evaluate the steady-state pharmacokinetics and tolerability of the coadministration of the PIs saquinavir and ritonavir (a CYP3A4 inhibitor used as a pharmacoenhancer of other PIs) and rifampin when coadministered in healthy HIV-negative volunteers. METHODS: In an open-label, randomized, one sequence, two-period crossover study involving 28 healthy HIV-negative volunteers, arm 1 was randomized to receive saquinavir/ritonavir 1000/100 mg twice daily while arm 2 received rifampin 600 mg once daily for 14 days. Both arms were then to receive concomitant saquinavir/ritonavir and rifampin for 2 additional weeks. Vital signs, electrocardiography, laboratory analyses, and blood levels of total saquinavir, ritonavir, rifampin, and desacetyl-rifampin, the primary metabolite of rifampin, were measured. RESULTS: In arm 1, 10/14 (71%) and, in arm 2, 11/14 (79%) participants completed the first study phase; eight participants in arm 1 and nine in arm 2 went on to receive both saquinavir/ritonavir and rifampin. Following substantial elevations (>/= grade 2) in hepatic transaminases in participants receiving the coadministered agents, the study was discontinued prematurely. Two participants in arm 1 displayed moderate elevations after five and four doses of rifampin, respectively. In arm 2, all participants experienced severe elevations within 4 days of initiating saquinavir/ritonavir. Clinical symptoms (e.g., nausea, vomiting, abdominal pain, and headache) were more common and severe in arm 2. Clinical symptoms abated and transaminases normalized following drug discontinuation. Limited pharmacokinetic data suggest a possible relationship between transaminase elevation and elevated rifampin and desacetyl-rifampin concentrations. CONCLUSIONS: Although not confirmed in HIV-infected patients, the data indicate that rifampin should not be coadministered with saquinavir/ritonavir.
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PMID:Unexpected Hepatotoxicity of Rifampin and Saquinavir/Ritonavir in Healthy Male Volunteers. 1938 36


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