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Chingwaru W, Vidmar J, Kapewangolo PT. The Potential of Sub-Saharan African Plants in the Management of Human Immunodeficiency Virus Infections: A Review. Phytother Res 2015; 29:1452-87. [PMID: 26337608 DOI: 10.1002/ptr.5433] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Revised: 07/09/2015] [Accepted: 07/22/2015] [Indexed: 12/28/2022]
Abstract
Acquired immunodeficiency syndrome, caused by human immunodeficiency virus (HIV), is a leading cause of mortality and morbidity in Sub-Saharan Africa, particularly in Southern Africa. Phytomedicines are an integral part of African health care. The Southern African flora is composed of at least 23 400 taxa. Despite this richness, only a handful of botanical products have been assessed for activities against HIV. This study aimed to summarize the potential of Sub-Saharan African plants, based on their composition and the established bioactivities, as sources of agents to manage HIV symptoms and as retroviral therapy. At least 109 plant species from 42 families and 94 genera that are found in Southern Africa were shown to have potential or actual activities against HIV. Only 12 of these plant species from 6 families and 10 genera were shown to harbour anti-HIV properties. Phytochemicals that include β-sitosterols, terpenoids, glycosides, saponins, flavonoids, triterpenoids, tannins and alkaloids, which harbour anti-HIV properties, were found to have a near cosmopolitan presence across the plant families in the region. Bioactivities of multiple phytochemicals are comparable to those for standard allopathic antiretroviral drugs. Research to determine the anti-HIV activities of the identified and other plants, including clinical trials, is long overdue.
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Affiliation(s)
- Walter Chingwaru
- Department of Biological Sciences, Faculty of Science, Bindura University of Science Education, P. Bag 1020, Bindura, Zimbabwe.,Institute Ceres/Zavod Ceres, Lahovna 16, 3000, Celje, Slovenia
| | - Jerneja Vidmar
- Institute Ceres/Zavod Ceres, Lahovna 16, 3000, Celje, Slovenia.,Department of Plastic and Reconstructive Surgery, University Medical Centre Maribor, Ljubljanska 5, 2000, Maribor, Slovenia
| | - Petrina T Kapewangolo
- Department of Chemistry and Biochemistry, University of Namibia, P/Bag 13301, 340 Mandume Ndemufayo Avenue, Pionierspark, Windhoek, Namibia
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Combinatorial approaches to the prevention and treatment of HIV-1 infection. Antimicrob Agents Chemother 2011; 55:1831-42. [PMID: 21343462 DOI: 10.1128/aac.00976-10] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The discovery of the human immunodeficiency virus type 1 (HIV-1) in 1982 soon led to the identification and development of antiviral compounds to be used in treatment strategies for infected patients. Early in the epidemic, drug monotherapies frequently led to treatment failures because the virus quickly developed resistance to the single drug. Following the advent of highly active antiretroviral therapy (HAART) in 1995, dramatic improvements in HIV-1-infected patient health and survival were realized as more refined combination therapies resulted in reductions in viral loads and increases in CD4+ T-cell counts. In the absence of an effective vaccine, prevention of HIV-1 infection has also gained traction as an approach to curbing the pandemic. The development of compounds as safe and effective microbicides has intensified and has focused on blocking the transmission of HIV-1 during all forms of sexual intercourse. Initial preclinical investigations and clinical trials of microbicides focused on single compounds effective against HIV-1. However, the remarkable successes achieved using combination therapy to treat systemic HIV-1 infection have subsequently stimulated the study and development of combination microbicides that will simultaneously inhibit multiple aspects of the HIV-1 transmission process by targeting incoming viral particles, virus-infected cells, and cells susceptible to HIV-1 infection. This review focuses on existing and developing combination therapies, covering preclinical development, in vitro and in vivo efficacy studies, and subsequent clinical trials. The shift in focus within the microbicide development field from single compounds to combination approaches is also explored.
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Krakovska O, Wahl LM. Drug-Sparing Regimens for HIV Combination Therapy: Benefits Predicted for “Drug Coasting”. Bull Math Biol 2007; 69:2627-47. [PMID: 17578648 DOI: 10.1007/s11538-007-9234-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Accepted: 05/04/2007] [Indexed: 12/01/2022]
Abstract
Structured Treatment Interruptions (STI) during HIV drug therapy were thought to potentially reduce side effects and toxicity, boost immune involvement, and possibly lower the viral set-point. Clinical trials of STI regimens, however, have had mixed results. We use an established mathematical model of HAART to estimate possible therapeutic outcomes for STI and for other, similar patterns in HIV combination therapy. We perform an exhaustive search of patterns of up to 60 days, for triple-drug combinations involving accurate pharmacokinetics for 12 specific antiviral drugs. The results of this analysis are consistent with recent clinical trials which have demonstrated that STI-type patterns, involving therapy interruption of weeks or months, are rarely optimal. Our analysis predicts, however, that the benefit of treatment can often be improved by including very short drug-free periods, during which the patient effectively "coasts" for a day or two on adequate drug concentrations due to the long half-life of some pharmaceuticals. Our analysis predicts many cases in which this may be achieved without increasing the risk of drug-resistance. This suggests that "drug coasting" patterns, significantly shorter than STI patterns, may merit further clinical investigation in efforts to find drug-sparing regimens for HIV.
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Affiliation(s)
- O Krakovska
- Department of Applied Mathematics, University of Western Ontario, London, ON, N6A 5B7, Canada.
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Swindells S. Non-nucleoside reverse transcriptase inhibitors in the treatment of human immunodeficiency virus infection. ACTA ACUST UNITED AC 2005. [DOI: 10.1517/14728214.2.1.155] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Morse GD, Reichman RC, Fischl MA, Para M, Leedom J, Powderly W, Demeter LM, Resnick L, Bassiakos Y, Timpone J, Cox S, Batts D. Concentration-targeted phase I trials of atevirdine mesylate in patients with HIV infection: dosage requirements and pharmacokinetic studies. The ACTG 187 and 199 study teams. Antiviral Res 2000; 45:47-58. [PMID: 10774589 DOI: 10.1016/s0166-3542(99)00073-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
RATIONALE To determine the dosage requirements and pharmacokinetics of atevirdine, a non-nucleoside reverse transcriptase inhibitor and its N-dealkylated metabolite (N-ATV) during phase I studies in patients receiving atevirdine alone or in combination with zidovudine. DESIGN Two open label, phase I studies conducted by the adult AIDS Clinical Trials Group (ACTG) in which atevirdine was administered every 8 h with weekly dosage adjustments to attain targeted trough plasma atevirdine concentrations. SETTING Five Adult AIDS Clinical Trials Units. PATIENTS Fifty patients (ACTG 199; n = 20 and ACTG 187; n = 30) with HIV-1 infection and < or =500 CD4+ lymphocytes/mm3. INTERVENTION ACTG 199; 12 weeks of therapy with atevirdine (dose-adjusted to achieve plasma trough atevirdine concentrations of 5-10 microM) and zidovudine (200 mg every 8 h). ACTG 187: 12 weeks of atevirdine monotherapy with atevirdine doses adjusted to achieve escalating, targeted trough plasma concentration ranges (5-13, 14-22, and 23-31 microM). MEASUREMENTS ACTG 199: atevirdine, N-ATV and zidovudine trough determinations weekly (all patients) and intensive pharmacokinetics (selected patients) prior to and at 6 and 12 weeks during combination therapy. ACTG 187: atevirdine and N-ATV trough concentrations over a 12 week period. Intensive pharmacokinetic studies were conducted prior to and at 4 and/or 8 weeks during atevirdine monotherapy in female patients. RESULTS Atevirdine plasma concentrations demonstrated considerable interpatient variability which was minimized by the adjustment of maintenance doses (range: 600-3900 mg/day) to achieve the desired trough concentrations. In ACTG 187, the mean number of weeks to attain the target value, and the percentage of patients who attained the target, was group I (5-11 microM): 2.7+/-2.4 weeks (92%); group II (12-21 microM): 2.6+/-1.8 (64%); and group III (22-31 microM): 7.0+/-5.6 weeks (27%). In ACTG 199 it was 3.2+/-5.2 weeks (95%) to achieve a 5-10 microM trough. Atevirdine demonstrated a mono- or bi-exponential decline among most of the patients studied after the first dose. During multiple-dosing a number of patterns of atevirdine disposition were observed including; rapid absorption with Cmax at 0.5-1 h, delayed absorption with Cmax at 3-4 h; minimal Cmax to Cmin fluctuation and Cmax to Cmin ratios of > 4. N-ATV (an inactive metabolite) patterns were characterized on day one by rapid appearance of the metabolite which peaked at 2-3 h after the dose and declined in a mono- or bi-exponential manner. At steady-state N-ATV patterns demonstrated minimal Cmax to Cmin fluctuations with some of the patients having more stable plasma N-ATV concentrations, while others had greater fluctuations week to week. CONCLUSIONS Considerable interpatient variability was noted in the pharmacokinetics of atevirdine. The variation in drug disposition was reflected in the range of daily doses required to attain the targeted trough concentrations. Atevirdine metabolism did not appear to reach saturation during chronic dosing in many of our patients, as reflected by the pattern of N-ATV/ATV ratios in plasma and saturation was not an explanation for the variation in dosing requirements. No apparent differences were noted between males and females, and atevirdine did not appear to influence zidovudine disposition.
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Affiliation(s)
- G D Morse
- Department of Pharmacy, State University of New York at Buffalo, Amherst 14260, USA
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Friedland GH, Pollard R, Griffith B, Hughes M, Morse G, Bassett R, Freimuth W, Demeter L, Connick E, Nevin T, Hirsch M, Fischl M. Efficacy and safety of delavirdine mesylate with zidovudine and didanosine compared with two-drug combinations of these agents in persons with HIV disease with CD4 counts of 100 to 500 cells/mm3 (ACTG 261). ACTG 261 Team. J Acquir Immune Defic Syndr 1999; 21:281-92. [PMID: 10428106 DOI: 10.1097/00126334-199908010-00005] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
To evaluate the antiretroviral activity of delavirdine mesylate, a non-nucleoside reverse transcriptase inhibitor of HIV-1, we performed a phase II, randomized, double-blind, multicenter trial comparing the three-drug combination of delavirdine with zidovudine and didanosine to two-drug combinations of these drugs. Patients with CD4 cell counts between 100 and 500 cells/mm3 without prior or <6 months of monotherapy with zidovudine or didanosine were randomized to one of four arms and observed on a follow-up basis for 48 weeks. In total, 544 patients were evaluated. In those assigned to the three-drug regimen, mean short-term (weeks 4-12) and long-term (weeks 40-48) change in CD4 cells from baseline were 49.3+/-8.1 and 65.4+/-13.4 cells/mm3, respectively; mean short-term and long-term HIV-1 RNA changes from baseline were -1.13 log10+/-0.12 and -0.73+/-0.12 copies/ml, respectively. These responses in CD4 cell counts and HIV-1 RNA levels were better in comparisons with each of the two-drug arms at all study points; however, differences were not consistently significant. Gastrointestinal side effects were experienced by 33% of patients (178 of 544), and 30% (121 of 407) receiving delavirdine experienced rash, only one case of which was severe. In this study, therapy with delavirdine + zidovudine + didanosine was safe and showed modest, but not always significant, antiviral activity and CD4 cell count benefit compared with two-drug regimens with these agents. Key
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Affiliation(s)
- G H Friedland
- AIDS Program-Yale School of Medicine, Yale University, New Haven, Connecticut 06510-2483, USA
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Been-Tiktak AM, Boucher CA, Brun-Vezinet F, Joly V, Mulder JW, Jost J, Cooper DA, Moroni M, Gatell JM, Staszewski S, Colebunders R, Stewart GJ, Hawkins DA, Johnson MA, Parkin JM, Kennedy DH, Hoy JF, Borleffs JC. Efficacy and safety of combination therapy with delavirdine and zidovudine: a European/Australian phase II trial. Int J Antimicrob Agents 1999; 11:13-21. [PMID: 10075273 DOI: 10.1016/s0924-8579(98)00082-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The objective of the study was to investigate the safety and antiviral effect of three delavirdine dose regimens or placebo in combination with zidovudine in patients who were already taking zidovudine. Eighty-nine symptomatic HIV-1 seropositive individuals with CD4 cell counts between 50 and 350 cells/microl were included in this trial The influence of combination therapy on viral susceptibility to both zidovudine and delavirdine was investigated. Death or the occurrence, or re-occurrence of an AIDS-defining illness was considered as a clinical endpoint. The addition of delavirdine to the antiretroviral treatment regimen resulted in a significant, but transient, reduction in virus load, as determined by quantitative RNA measurements. CD4+ cell count did not change significantly. Susceptibility to zidovudine remained unchanged after 12 weeks of combination therapy, while 70% of the patients demonstrated a substantial decrease (> 10-fold) in sensitivity to delavirdine. Two patients suffered from an AIDS-defining disease during the study. No deaths occurred. Generally, the drug appeared to be safe. Skin rash was the most frequently observed adverse event (52%). In most patients the rash either resolved spontaneously or was treated successfully with a short course of antihistamines. The definite place of the compound in the management of HIV disease, in particular when given in combination with other antiretroviral agents, remains to be further explored.
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Affiliation(s)
- A M Been-Tiktak
- Department of Internal Medicine, Eijkman-Winkler Institute of Medical Microbiology, University Hospital, Utrecht, The Netherlands
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Enting RH, Hoetelmans RM, Lange JM, Burger DM, Beijnen JH, Portegies P. Antiretroviral drugs and the central nervous system. AIDS 1998; 12:1941-55. [PMID: 9814862 DOI: 10.1097/00002030-199815000-00005] [Citation(s) in RCA: 145] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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9
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Cheng CL, Smith DE, Carver PL, Cox SR, Watkins PB, Blake DS, Kauffman CA, Meyer KM, Amidon GL, Stetson PL. Steady-state pharmacokinetics of delavirdine in HIV-positive patients: effect on erythromycin breath test. Clin Pharmacol Ther 1997; 61:531-43. [PMID: 9164415 DOI: 10.1016/s0009-9236(97)90133-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE The steady-state kinetics of delavirdine and desisopropyldelavirdine were evaluated in human immunodeficiency virus-positive patients after escalating oral doses and after repeated oral administrations at the same dose level. STUDY DESIGN Patients (n = 8 males) were given escalating oral doses of delavirdine mesylate, in a sequential fashion, over 14 days for phases 1 (200 mg every 8 hours), 2 (300 mg every 8 hours), and 3 (400 mg every 8 hours). Control patients (n = 4 males) were given 300 mg oral doses of drug every 8 hours for all three phases. Hepatic CYP3A activity was evaluated with the erythromycin breath test (ERMBT). RESULTS In the escalating-dose group, delavirdine displayed nonlinear kinetics as indicated by the decreasing oral clearance, maximum steady-state plasma concentration/minimum steady-state plasma concentration ratio, and log-linear terminal rate constant, as well as by increasing half-life at higher doses; the ratio of desisopropyl-delavirdine formation clearance to elimination clearance was also reduced. In the control group, the kinetics of delavirdine and desisopropyl-delavirdine were unchanged. Plasma protein binding was linear for delavirdine in the escalating-dose and control groups; on average, the fraction unbound was about 2.3% and 2.0%, respectively. Hepatic CYP3A activity was markedly reduced after short- and long-term exposure to all doses of delavirdine mesylate. Delavirdine could maximally inhibit 70% to 75% of predose ERMBT values, with an IC50 of about 0.9 mumol/L. CONCLUSION Delavirdine is a potent and reversible inhibitor of hepatic CYP3A; it is also a substrate for this CYP450 isoform. It is likely that delavirdine will exhibit drug-drug interactions when coadministered with other CYP3A substrates.
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Affiliation(s)
- C L Cheng
- College of Pharmacy, Upjohn Center for Clinical Pharmacology, University of Michigan, Ann Arbor 48109-0504, USA
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Perrault WR, Shephard KP, LaPean LA, Krook MA, Dobrowolski PJ, Lyster MA, McMillan MW, Knoechel DJ, Evenson GN, Watt W, Pearlman BA. Production Scale Synthesis of the Non-Nucleoside Reverse Transcriptase Inhibitor Atevirdine Mesylate (U-87,201E). Org Process Res Dev 1997. [DOI: 10.1021/op9600318] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- William R. Perrault
- Chemical Process Research and Development, Chemical Research Preparations, and Structural, Analytical, and Medicinal Chemistry Departments, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001-0199
| | - K. Paul Shephard
- Chemical Process Research and Development, Chemical Research Preparations, and Structural, Analytical, and Medicinal Chemistry Departments, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001-0199
| | - Lori A. LaPean
- Chemical Process Research and Development, Chemical Research Preparations, and Structural, Analytical, and Medicinal Chemistry Departments, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001-0199
| | - Mark A. Krook
- Chemical Process Research and Development, Chemical Research Preparations, and Structural, Analytical, and Medicinal Chemistry Departments, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001-0199
| | - Paul J. Dobrowolski
- Chemical Process Research and Development, Chemical Research Preparations, and Structural, Analytical, and Medicinal Chemistry Departments, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001-0199
| | - Mark A. Lyster
- Chemical Process Research and Development, Chemical Research Preparations, and Structural, Analytical, and Medicinal Chemistry Departments, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001-0199
| | - Moses W. McMillan
- Chemical Process Research and Development, Chemical Research Preparations, and Structural, Analytical, and Medicinal Chemistry Departments, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001-0199
| | - Donald J. Knoechel
- Chemical Process Research and Development, Chemical Research Preparations, and Structural, Analytical, and Medicinal Chemistry Departments, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001-0199
| | - Gerald N. Evenson
- Chemical Process Research and Development, Chemical Research Preparations, and Structural, Analytical, and Medicinal Chemistry Departments, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001-0199
| | - William Watt
- Chemical Process Research and Development, Chemical Research Preparations, and Structural, Analytical, and Medicinal Chemistry Departments, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001-0199
| | - Bruce A. Pearlman
- Chemical Process Research and Development, Chemical Research Preparations, and Structural, Analytical, and Medicinal Chemistry Departments, Pharmacia & Upjohn, Inc., Kalamazoo, Michigan 49001-0199
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Been-Tiktak AM, Williams I, Vrehen HM, Richens J, Aldam D, van Loon AM, Loveday C, Boucher CA, Ward P, Weller IV, Borleffs JC. Safety, tolerance, and efficacy of atevirdine in asymptomatic human immunodeficiency virus-infected individuals. Antimicrob Agents Chemother 1996; 40:2664-8. [PMID: 8913487 PMCID: PMC163598 DOI: 10.1128/aac.40.11.2664] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Atevirdine is a nonnucleoside reverse transcriptase inhibitor of human immunodeficiency virus type 1 (HIV-1). In this study we investigated the effect of atevirdine in asymptomatic antiretroviral naive HIV-infected patients with CD4+ cell counts of between 200 and 750 cells per mm3. Patients were randomized to receive 600 mg of atevirdine (n = 15) or a placebo (n = 15) three times a day for 12 weeks. There was no statistically significant effect of atevirdine on viral loads (HIV p24 antigen and HIV-1 RNA levels by PCR) or CD4+ cell counts. The data do not support the use of atevirdine as a monotherapy in the treatment of HIV-infected patients.
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Affiliation(s)
- A M Been-Tiktak
- Department of Internal Medicine, University Hospital Utrecht, The Netherlands
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What can be Expected from Non-nucleoside Reverse Transcriptase Inhibitors (NNRTIs) in the Treatment of Human Immunodeficiency Virus Type 1 (HIV-1) Infections? Rev Med Virol 1996; 6:97-117. [PMID: 10398452 DOI: 10.1002/(sici)1099-1654(199606)6:2<97::aid-rmv168>3.0.co;2-4] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Morse GD, Fischl MA, Shelton MJ, Borin MT, Driver MR, DeRemer M, Lee K, Wajszczuk CP. Didanosine reduces atevirdine absorption in subjects with human immunodeficiency virus infections. Antimicrob Agents Chemother 1996; 40:767-71. [PMID: 8851608 PMCID: PMC163195 DOI: 10.1128/aac.40.3.767] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Atevirdine is a nonnucleoside reverse transcriptase inhibitor with in vitro activity against human immunodeficiency virus type 1 and is currently in phase II clinical trials. Atevirdine is most soluble at a pH of < 2, and therefore, normal gastric acidity is most likely necessary for optimal bioavailability. Because of the rapid development of resistance in vitro, atevirdine is being evaluated in combination with didanosine and/or zidovudine in both two- and three-drug combination regimens. To examine the influence of concurrent didanosine (buffered tablet formulation) on the disposition of atevirdine, 12 human immunodeficiency virus type 1-infected subjects (mean CD4+ cell count, 199 cells per mm3; range, 13 to 447 cells/mm3) participated in a three-way, partially randomized, crossover, single-dose study to evaluate the pharmacokinetics of didanosine and atevirdine when each drug was given alone (treatments A and B, respectively) versus concurrently (treatment C). Concurrent administration of didanosine and atevirdine significantly reduced the maximum concentration of atevirdine in serum from 3.45 +/- 2.8 to 0.854 +/- 0.33 microM (P = 0.004). Likewise, the mean atevirdine area under the concentration-time curve from 0 to 24 h after administration of the combination was reduced to 6.47 +/- 2.2 microM.h (P = 0.004) relative to a value of 11.3 +/- 4.8 microM.h for atevirdine alone. Atevirdine had no statistically significant effect on the pharmacokinetic parameters of didanosine. Concurrent administration of single doses of atevirdine and didanosine resulted in a markedly lower maximum concentration of atevirdine in serum and area under the concentration-time curve, with a minimal effect on the disposition of didanosine. It is unknown whether an interaction of similar magnitude would occur under steady-state conditions; thus, combination regimens which include both atevirdine and didanosine should be designed so that their administration times are separated. Since the duration of the buffering effect of didanosine formulations is unknown, atevirdine should be given prior to didanosine.
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Affiliation(s)
- G D Morse
- Department of Pharmacy Practice, State University of New York at Buffalo, Amherst, NY 14260, USA
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Abstract
Depending on the stage of their intervention with the viral replicative cycle, human immunodeficiency virus inhibitors could be divided into the following groups: (i) adsorption inhibitors (i.e., CD4 constructs, polysulfates, polysulfonates, polycarboxylates, and polyoxometalates), (ii) fusion inhibitors (i.e., plant lectins, succinylated or aconitylated albumins, and betulinic acid derivatives), (iii) uncoating inhibitors (i.e., bicyclams), (iv) reverse transcription inhibitors acting either competitively with the substrate binding site (i.e., dideoxynucleoside analogs and acyclic nucleoside phosphonates) or allosterically with a nonsubstrate binding site (i.e., non-nucleoside reverse transcriptase inhibitors), (v) integration inhibitors, (vi) DNA replication inhibitors, (vii) transcription inhibitors (i.e., antisense oligodeoxynucleotides and Tat antagonists), (viii) translation inhibitors (i.e., antisense oligodeoxynucleotides and ribozymes), (ix) maturation inhibitors (i.e., protease inhibitors, myristoylation inhibitors, and glycosylation inhibitors), and finally, (x) budding (assembly/release) inhibitors. Current knowledge, including the therapeutic potential, of these various inhibitors is discussed. In view of their potential clinical the utility, the problem of virus-drug resistance and possible strategies to circumvent this problem are also addressed.
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Affiliation(s)
- E De Clercq
- Rega Institute for Medical Research, Katholieke Universiteit Leuven, Belgium
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Been-Tiktak AM, Vrehen HM, Schneider MM, van der Feltz M, Branger T, Ward P, Cox SR, Harry JD, Borleffs JC. Safety, tolerance, and pharmacokinetics of atevirdine mesylate (U-87201E) in asymptomatic human immunodeficiency virus-infected patients. Antimicrob Agents Chemother 1995; 39:602-7. [PMID: 7793859 PMCID: PMC162591 DOI: 10.1128/aac.39.3.602] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Atevirdine mesylate (U-87201E) is a new nonnucleoside (bisheteroarylpiperazine) inhibitor of human immunodeficiency virus type 1 reverse transcriptase. In a double-blind, escalating single-dose study the safety, tolerance, and pharmacokinetics of atevirdine mesylate were investigated in 24 asymptomatic human immunodeficiency virus-seropositive male patients. Each patient received one single oral dose of atevirdine mesylate and placebo separated by an interval of 1 to 3 weeks. For each dose level (400, 800, 1,200, and 1,600 mg) six patients received drug and placebo on separate occasions. Blood samples were collected before dosing and at intervals afterward for safety evaluation and estimation of atevirdine and metabolite levels. The concentrations of atevirdine and its principal metabolite (U-89255) in serum were determined by high-performance liquid chromatography. The results of the study showed that atevirdine mesylate is well tolerated at all dose levels. No clinically significant effects on vital signs, electrocardiograms, or laboratory tests were observed. Occasional headache and nausea were reported both in the drug group and in the placebo group. The times to peak values were relatively short (0.5 to 1.0 h), suggesting a rapid absorption. The maximum concentrations of drug in serum were 1.4 microM (400 mg), 4.2 microM (800 mg), 7.3 microM (1,200 mg), and 5.8 microM (1,600 mg). The values of the pharmacokinetic parameters for atevirdine were found to have relatively large intersubject variabilities, and consequently, the study had little power to detect dose-dependent changes in the values of the pharmacokinetic parameters. The oral clearance of atevirdine tended to increase by 90% as the atevirdine mesylate doses increased from 400 to 1,600 mg, but this change in oral clearance was not statistically significant. The values of the pharmacokinetic parameters determined in the study were similar to those found in a previous single-dose study in healthy volunteers.
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Affiliation(s)
- A M Been-Tiktak
- Department of Internal Medicine, University Hospital Utrecht, The Netherlands
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Mazzulli T, Rusconi S, Merrill DP, D'Aquila RT, Moonis M, Chou TC, Hirsch MS. Alternating versus continuous drug regimens in combination chemotherapy of human immunodeficiency virus type 1 infection in vitro. Antimicrob Agents Chemother 1994; 38:656-61. [PMID: 8031028 PMCID: PMC284521 DOI: 10.1128/aac.38.4.656] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
We compared the in vitro efficacies of two-, three-, and four-drug combinations given continuously or in alternating regimens against a clinical isolate of human immunodeficiency virus type 1. In H9 cells and peripheral blood mononuclear cells, at the drug concentrations used in this study, there was greater suppression of human immunodeficiency virus type 1 infection as the number of drugs in the regimen was increased from one to four simultaneously administered agents. Although alternating drug regimens were effective, they were not better than continuous administration of either single drugs or combinations of agents and were less effective than giving all drugs of an alternating regimen simultaneously.
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Affiliation(s)
- T Mazzulli
- Infectious Disease Unit, Massachusetts General Hospital, Harvard Medical School, Boston 02114
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Chong KT, Pagano PJ, Hinshaw RR. Bisheteroarylpiperazine reverse transcriptase inhibitor in combination with 3'-azido-3'-deoxythymidine or 2',3'-dideoxycytidine synergistically inhibits human immunodeficiency virus type 1 replication in vitro. Antimicrob Agents Chemother 1994; 38:288-93. [PMID: 7514857 PMCID: PMC284442 DOI: 10.1128/aac.38.2.288] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Bisheteroarylpiperazine compounds are nonnucleoside reverse transcriptase inhibitors of human immunodeficiency virus type 1 (HIV-1). To provide a rationale for combination therapy with a second-generation bisheteroarylpiperazine, we investigated the effect of U-90152 in combination with 3'-azido-3'-deoxythymidine (AZT) or 2',3'-dideoxycytidine (ddC). HIV-1-infected cells were cultured in the presence of test compounds, and drug effects on p24 core antigen production were measured by an enzyme-linked immunosorbent assay. In a CD4+ T-cell line (H9) infected with HIV-1IIIB, the 50% effective concentrations for U-90152, AZT, and ddC were 6.0, 80.4, and 31.8 nM, respectively. In human peripheral blood mononuclear cells infected with the molecularly cloned clinical isolate HIV-1JRCSF, the 50% effective concentrations for U-90152, AZT, and ddC were 5.3, 5.9, and 25.0 nM, respectively. Over a range of drug concentrations (U-90152 and AZT at 0.3, 1, 3, 10, and 30 nM; ddC at 3, 10, 30, and 100 nM), U-90152 in combination with AZT or ddC synergistically inhibited the replication of a laboratory-adapted strain and a clinical isolate of HIV-1.
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Affiliation(s)
- K T Chong
- Upjohn Laboratories, Kalamazoo, Michigan 49001
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