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Velozo CT, Cabral LM, Pinto EC, de Sousa VP. Lopinavir/Ritonavir: A Review of Analytical Methodologies for the Drug Substances, Pharmaceutical Formulations and Biological Matrices. Crit Rev Anal Chem 2021; 52:1846-1862. [PMID: 34024199 DOI: 10.1080/10408347.2021.1920364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Lopinavir/ritonavir is a potent coformulation of protease inhibitors used against HIV infection. Lopinavir is the main responsible for viral load suppression, whereas ritonavir is a pharmacokinetic enhancer. Both of them have recently gained relevance as candidate drugs against severe coronavirus disease (COVID-19). However, significant beneficial effects were not observed in randomized clinical trials. This review summarizes the main physical-chemical, pharmacodynamic, and pharmacokinetic properties of ritonavir and lopinavir, along with the analytical methodologies applied for biological matrices, pharmaceutical formulations, and stability studies. The work also aimed to provide a comprehensive impurity profile for the combined formulation. Several analytical methods in four different pharmacopeias and 37 articles in literature were evaluated and summarized. Chromatographic methods for these drugs frequently use C8 or C18 stationary phases with acetonitrile and phosphate buffer (with ultraviolet detection) or acetate buffer (with tandem mass spectrometry detection) as the mobile phase. Official compendia methods show disadvantages as extended total run time and complex mobile phases. HPLC tandem-mass spectrometry provided high sensitivity in methodologies applied for human plasma and serum samples, supporting the therapeutic drug monitoring in HIV patients. Ritonavir and lopinavir major degradation products arise in alkaline and acidic environments, respectively. Other non-chromatographic methods were also summarized. Establishing the impurity profile for the combined formulation is challenging due to a large number of impurities reported. Easier and faster analytical methods for impurity assessment are still needed.
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Affiliation(s)
- Carolina Trajano Velozo
- Department of Drugs and Pharmaceutics, Faculty of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Lucio Mendes Cabral
- Department of Drugs and Pharmaceutics, Faculty of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Eduardo Costa Pinto
- Department of Drugs and Pharmaceutics, Faculty of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Valéria Pereira de Sousa
- Department of Drugs and Pharmaceutics, Faculty of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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Charbe NB, Zacconi FC, Amnerkar N, Ramesh B, Tambuwala MM, Clementi E. Bio-analytical Assay Methods used in Therapeutic Drug Monitoring of Antiretroviral Drugs-A Review. CURRENT DRUG THERAPY 2019. [DOI: 10.2174/1574885514666181217125550] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Background: Several clinical trials, as well as observational statistics, have exhibited that the advantages of antiretroviral [ARV] treatment for humans with Human Immunodeficiency Virus / Acquired Immune Deficiency Syndrome HIV/AIDS exceed their risks. Therapeutic drug monitoring [TDM] plays a key role in optimization of ARV therapy. Determination of ARV’s in plasma, blood cells, and other biological matrices frequently requires separation techniques capable of high effectiveness, specific selectivity and high sensitivity. High-performance liquid chromatography [HPLC] coupled with ultraviolet [UV], Photodiode array detectors [PDA], Mass spectrophotometer [MS] detectors etc. are the important quantitative techniques used for the estimation of pharmaceuticals in biological samples. </P><P> Objective: This review article is aimed to give an extensive outline of different bio-analytical techniques which have been reported for direct quantitation of ARV’s. This article aimed to establish an efficient role played by the TDM in the optimum therapeutic outcome of the ARV treatment. It also focused on establishing the prominent role played by the separation techniques like HPLC and UPLC along with the detectors like UV and Mass in TDM. </P><P> Methods: TDM is based on the principle that for certain drugs, a close relationship exists between the plasma level of the drug and its clinical effect. TDM is of no value if the relationship does not exist. The analytical methodology employed in TDM should: 1) distinguish similar compounds; 2) be sensitive and precise and 3) is easy to use. </P><P> Results: This review highlights the advancement of the chromatographic techniques beginning from the HPLC-UV to the more advanced technique like UPLC-MS/MS. TDM is essential to ensure adherence, observe viral resistance and to personalize ARV dose regimens. It is observed that the analytical methods like immunoassays and liquid chromatography with detectors like UV, PDA, Florescent, MS, MS/MS and Ultra performance liquid chromatography (UPLC)-MS/MS have immensely contributed to the clinical outcome of the ARV therapy. Assay methods are not only helping physicians in limiting the side effects and drug interactions but also assisting in monitoring patient’s compliance. </P><P> Conclusion: The present review revealed that HPLC has been the most widely used system irrespective of the availability of more sensitive chromatographic technique like UPLC.
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Affiliation(s)
- Nitin B. Charbe
- Departamento de Quimica Organica, Facultad de Quimica y de Farmacia, Pontificia Universidad Catolica de Chile, Av. Vicuna McKenna 4860, Macul, Santiago 7820436, Chile
| | - Flavia C. Zacconi
- Departamento de Quimica Organica, Facultad de Quimica y de Farmacia, Pontificia Universidad Catolica de Chile, Av. Vicuna McKenna 4860, Macul, Santiago 7820436, Chile
| | - Nikhil Amnerkar
- Adv V. R. Manohar Institute of Diploma in Pharmacy, Wanadongri, Hingna Road, Nagpur, Maharashtra 441110, India
| | - B. Ramesh
- Sri Adichunchunagiri University, Sri Adichunchunagiri College of Pharmacy, BG Nagar, Karnataka 571418, India
| | - Murtaza M. Tambuwala
- School of Pharmacy and Pharmaceutical Science, University of Ulster, Coleraine, County Londonderry, Northern Ireland BT52 1SA, United Kingdom
| | - Emilio Clementi
- Clinical Pharmacology Unit, CNR Institute of Neuroscience, Department of Biomedical and Clinical Sciences, Luigi Sacco University Hospital, Universita di Milano, Milan, Italy
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Zelena L, Reznicek J, Ceckova M, Sklenarova H. Universal efavirenz determination in transport study, rat placenta perfusion and placenta lysate by HPLC-UV. J Pharm Biomed Anal 2017; 137:70-77. [PMID: 28092857 DOI: 10.1016/j.jpba.2017.01.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 01/04/2017] [Accepted: 01/06/2017] [Indexed: 11/24/2022]
Abstract
Efavirenz is an antiretroviral drug used in the treatment of HIV-positive patients. A simple, fast and sensitive high-performance liquid chromatography (HPLC) method was developed in order to determine efavirenz in three types of samples provided from pharmacokinetic studies. The analysis took 5min and was performed using a C18 analytical column (Discovery HS C18, 150×4.6mm, particle size of 5μm) in isocratic mode with a mobile phase containing acetonitrile and water (65:35, v/v), a flow rate of 1.6mLmin-1, a sample volume of 10μL and UV detection at 245nm. Three different sample matrices (Opti-MEM medium, Krebs perfusion liquid and tissue lysate) and their treatment (dilution, SPE) were considered. The validated method was applied for the analysis of 805 real samples arising from in vitro transcellular transport assays and in vivo organ perfusion experiments in order to evaluate the interaction of efavirenz with ATP-dependent drug efflux transporters. The lack of interaction of efavirenz with ABCB1, ABCG2 and ABCC2 transporters as well as technical aspects of this analysis, including the adhesion of efavirenz to the plastic materials and the stability of the drug during different tissue lysis approaches are discussed.
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Affiliation(s)
- Lucie Zelena
- Department of Analytical Chemistry, Faculty of Pharmacy in Hradec Kralove, Charles University in Prague, Czechia
| | - Josef Reznicek
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Kralove, Charles University in Prague, Czechia
| | - Martina Ceckova
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Kralove, Charles University in Prague, Czechia
| | - Hana Sklenarova
- Department of Analytical Chemistry, Faculty of Pharmacy in Hradec Kralove, Charles University in Prague, Czechia.
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Bhatt NB, Baudin E, Meggi B, da Silva C, Barrail-Tran A, Furlan V, Grinsztejn B, Bonnet M, Taburet AM. Nevirapine or efavirenz for tuberculosis and HIV coinfected patients: exposure and virological failure relationship. J Antimicrob Chemother 2014; 70:225-32. [PMID: 25239466 PMCID: PMC4267502 DOI: 10.1093/jac/dku348] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Objectives We describe nevirapine and efavirenz exposure on and off tuberculosis treatment and consequences for virological efficacy and tolerance in patients included in the ANRS 12146/12214-CARINEMO trial. Methods Participants were randomly selected to receive either nevirapine at 200 mg twice daily (n = 256) or efavirenz at 600 mg daily (n = 270), both combined with two nucleoside analogues. Blood samples were drawn 12 h after nevirapine or efavirenz administration, while on tuberculosis treatment and after tuberculosis treatment discontinuation. In 62 participants, samples taken 12 h after drug administration were drawn weekly for the first month of ART. Sixteen participants participated in an extensive pharmacokinetic study of nevirapine. Concentrations were compared with the therapeutic ranges of 3000–8000 ng/mL for nevirapine and 1000–4000 ng/mL for efavirenz. Results Nevirapine concentrations at the end of the first week of treatment (on antituberculosis drugs) did not differ from concentrations off tuberculosis treatment, but declined thereafter. Concentrations at steady-state were 4111 ng/mL at week 12 versus 6095 ng/mL at week 48 (P < 0.0001). Nevirapine concentrations <3000 ng/mL were found to be a risk factor for virological failure. Efavirenz concentrations were higher on than off tuberculosis treatment (2700 versus 2450 ng/mL, P < 0.0001). Conclusions The omission of the 2 week lead-in dose of nevirapine prevented low concentrations at treatment initiation but did not prevent the risk of virological failure. Results support the WHO recommendation to use efavirenz at 600 mg daily in patients on rifampicin-based antituberculosis therapy.
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Affiliation(s)
- Nilesh B Bhatt
- Instituto Nacional de Saúde, Ministry of Health, Maputo, Mozambique Instituto de Pesquisa Clínica Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | | | - Bindiya Meggi
- Instituto Nacional de Saúde, Ministry of Health, Maputo, Mozambique
| | | | - Aurélie Barrail-Tran
- Assistance Publique Hôpitaux de Paris, Bicêtre Hospital, Hôpitaux Universitaires Paris Sud, Clinical Pharmacy, Paris, France EA4123, Faculty of Pharmacy, University Paris Sud, Paris, France
| | - Valérie Furlan
- Assistance Publique Hôpitaux de Paris, Bicêtre Hospital, Hôpitaux Universitaires Paris Sud, Clinical Pharmacy, Paris, France
| | - Beatriz Grinsztejn
- Instituto de Pesquisa Clínica Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | | | - Anne-Marie Taburet
- Assistance Publique Hôpitaux de Paris, Bicêtre Hospital, Hôpitaux Universitaires Paris Sud, Clinical Pharmacy, Paris, France
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Bertrand J, Verstuyft C, Chou M, Borand L, Chea P, Nay KH, Blanc FX, Mentré F, Taburet AM, Sok T, Goldfeld AE, Blanc FX, Laureillard D, Marcy O, Fernandez M, Chan S, Nerrienet E, Vong S, Madec Y, Rekacewicz C, Saman M, Leng C, Ay SS, Pheng P, Chan LH, Suom S, Men NR, Phon K, Kun S, Chea S, Toeung P, Yoeun Y, Dy KK, Kry P, Meardey K, Guillard B, Srey C, Keo C, Ngin S, Sar B, Nouhin J, Ken S, Chea K, Kong K, Tun S, Say L, Sok KE, Lim HK. Dependence of Efavirenz- and Rifampicin-Isoniazid–Based Antituberculosis Treatment Drug-Drug Interaction on CYP2B6 and NAT2 Genetic Polymorphisms: ANRS 12154 Study in Cambodia. J Infect Dis 2013; 209:399-408. [DOI: 10.1093/infdis/jit466] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Affiliation(s)
- Julie Bertrand
- Genetics Institute, University College London, United Kingdom
- UMR738 INSERM, University Paris Diderot, Paris
| | - Céline Verstuyft
- Assistance Publique-Hôpitaux de Paris, Bicêtre Paris-Sud University Hospital, Le Kremlin Bicêtre
- University Paris-Sud,
EA4123, Chatenay-Malabry, France
| | | | | | - Phalla Chea
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia
| | | | - François-Xavier Blanc
- Assistance Publique-Hôpitaux de Paris, Bicêtre Paris-Sud University Hospital, Le Kremlin Bicêtre
| | | | - Anne-Marie Taburet
- Assistance Publique-Hôpitaux de Paris, Bicêtre Paris-Sud University Hospital, Le Kremlin Bicêtre
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Kou H, Ye M, Fu Q, Han Y, Du X, Xie J, Zhu Z, Li T. Simultaneous quantification of lopinavir and ritonavir in human plasma by high performance liquid chromatography coupled with UV detection. SCIENCE CHINA-LIFE SCIENCES 2012; 55:321-7. [PMID: 22566088 DOI: 10.1007/s11427-012-4303-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 03/09/2012] [Indexed: 11/30/2022]
Abstract
High performance liquid chromatography was coupled with UV detection for simultaneous quantification of lopinavir (LPV) and ritonavir (RTV) in human plasma. This assay was sensitive, accurate and simple, and only used 200 μL of plasma sample. Samples were liquid-liquid extracted, and diazepam was used as an internal standard. The chromatographic separation was achieved on a C18 reversed-phase analytic column with a mobile phase of acetonitrile-sodium dihydrogen phosphate buffer (10 mmol L(-1), pH 4.80) (60:40, v/v). UV detection was conducted at 205 nm and the column oven was set at 40°C. Calibration curves were constructed between 0.5-20 μg mL(-1) for LPV and 0.05-5 μg mL(-1) for RTV. The relative standard deviations were 2.16%-3.20% for LPV and 2.12%-2.60% for RTV for intra-day analysis, and 2.34%-4.04% for LPV and 0.31%-4.94% for RTV for inter-day analysis. The accuracy was within 100%±10%. The mean extraction recoveries were 79.17%, 52.26% and 91.35% for RTV, LPV and diazepam, respectively. This method was successfully applied to human plasma samples from patients orally administered a salvage regimen of lopinavir-ritonavir tablets.
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Affiliation(s)
- Huijuan Kou
- Department of Infectious Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences-Peking Union Medical College, Beijing 100730, China
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Mishra TD, Kurani H, Singhal P, Shrivastav PS. Simultaneous Quantitation of HIV-Protease Inhibitors Ritonavir, Lopinavir and Indinavir in Human Plasma by UPLC-ESI-MS-MS. J Chromatogr Sci 2012; 50:625-35. [DOI: 10.1093/chromsci/bms048] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Raviolo MA, Breva IC, Esteve-Romero J. Screening and monitoring antiretrovirals and antivirals in the serum of acquired immunodeficiency syndrome patients by micellar liquid chromatography. J Chromatogr A 2009; 1216:3546-52. [DOI: 10.1016/j.chroma.2009.01.082] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2008] [Revised: 01/22/2009] [Accepted: 01/26/2009] [Indexed: 11/26/2022]
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Jain R, Agarwal S, Mandava NK, Sheng Y, Mitra AK. Interaction of dipeptide prodrugs of saquinavir with multidrug resistance protein-2 (MRP-2): Evasion of MRP-2 mediated efflux. Int J Pharm 2008; 362:44-51. [DOI: 10.1016/j.ijpharm.2008.06.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2007] [Revised: 06/04/2008] [Accepted: 06/05/2008] [Indexed: 11/17/2022]
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Teicher E, Vincent I, Bonhomme-Faivre L, Abbara C, Barrail A, Boissonnas A, Duclos-Vallée JC, Taburet AM, Samuel D, Vittecoq D. Effect of highly active antiretroviral therapy on tacrolimus pharmacokinetics in hepatitis C virus and HIV co-infected liver transplant recipients in the ANRS HC-08 study. Clin Pharmacokinet 2008; 46:941-52. [PMID: 17922559 DOI: 10.2165/00003088-200746110-00002] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
OBJECTIVE To characterise the interactions between tacrolimus and antiretroviral drug combinations in hepatitis C virus-HIV co-infected patients who had received a liver transplant. DESIGN An observational, open-label, multiple-dose, two-period, one-sequence design clinical trial in which patients received tacrolimus as an immunosuppressive therapy during the postoperative period and then had an antiretroviral drug regimen added. Tacrolimus pharmacokinetics were evaluated at steady state during these two periods. METHODS Fourteen patients participated in the study and seven participated in the intensified pharmacokinetic protocol. Patients were included if they had undergone liver transplantation for end-stage chronic hepatitis C, absence of opportunistic infection, a CD4 cell count of >150 cells/microL and an undetectable HIV plasma viral load (<50 copies/mL) under highly active antiretroviral therapy. During the posttransplantation period, the tacrolimus dose was adjusted according to blood concentrations. When liver function and the tacrolimus dose were stable, antiretroviral therapy was reintroduced. RESULTS When lopinavir/ritonavir were added to the tacrolimus regimen (seven patients), the tacrolimus dose was reduced by 99% to maintain the tacrolimus concentration within the therapeutic range. Only two patients were treated with nelfinavir, which led to a wide variation in inhibition of tacrolimus metabolism. When efavirenz (four patients) or a nucleoside analogue combination (one patient) was added, very little change in tacrolimus dosing was required. CONCLUSION The lopinavir/ritonavir combination markedly inhibited tacrolimus metabolism, whereas the effect of efavirenz was small. Tacrolimus dosing must be optimised according to therapeutic drug monitoring and the antiretroviral drug combination.
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Affiliation(s)
- Elina Teicher
- Internal Medicine and Infectious Diseases Department, Hôpital Paul Brousse, Assistance Publique Hôpitaux de Paris (AP-HP), Paris, France
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Dogan-Topal B, Ozkan SA, Uslu B. Simultaneous Determination of Abacavir, Efavirenz and Valganciclovir in Human Serum Samples by Isocratic HPLC-DAD Detection. Chromatographia 2007. [DOI: 10.1365/s10337-007-0302-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Rebiere H, Mazel B, Civade C, Bonnet PA. Determination of 19 antiretroviral agents in pharmaceuticals or suspected products with two methods using high-performance liquid chromatography. J Chromatogr B Analyt Technol Biomed Life Sci 2006; 850:376-83. [PMID: 17196448 DOI: 10.1016/j.jchromb.2006.12.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2006] [Revised: 12/05/2006] [Accepted: 12/07/2006] [Indexed: 11/21/2022]
Abstract
Three classes of antiretroviral agents are usually available for the treatment of HIV infection: nucleoside reverse transcriptase inhibitors (IN), non-nucleoside reverse transcriptase inhibitors (INN) and protease inhibitors (IP). Two methods by reversed-phase liquid chromatography were developed for the analysis of 19 antiretroviral molecules belonging to these three therapeutic classes and used in medicinal products. Both of these HPLC techniques use a C18 column and UV detection. The first method is for IN family analysis and allows eight molecules to be separated: zalcitabine, lamivudine, amdoxovir, emtricitabine, didanosine, stavudine, zidovudine and abacavir. The second method is for INN and IP family analysis and allows 11 molecules to be separated: fosamprenavir, nevirapine, indinavir, amprenavir, saquinavir, atazanavir, ritonavir, lopinavir, efavirenz, nelfinavir and tipranavir. The combination of these two methods makes possible the quality control of mono-, bi- or tri-therapy pharmaceutical products and the detection of illegal products sold particularly in developing countries.
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Affiliation(s)
- Hervé Rebiere
- Agence Française de Sécurité Sanitaire des Produits de Santé, Direction des Laboratoires et des Contrôles, Unité Physico Chimie 2, 635 rue de la Garenne, 34740 Vendargues, France.
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Panhard X, Goujard C, Legrand M, Taburet AM, Diquet B, Mentré F. Population pharmacokinetic analysis for nelfinavir and its metabolite M8 in virologically controlled HIV-infected patients on HAART. Br J Clin Pharmacol 2006; 60:390-403. [PMID: 16187971 PMCID: PMC1884828 DOI: 10.1111/j.1365-2125.2005.02456.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
AIMS To describe the pharmacokinetics of nelfinavir and its main metabolite M8 in HIV-infected patients with a sustained virological response, to characterize the effect of covariates and to estimate inter- and intra-individual variability in the pharmacokinetics. METHODS Three hundred and twenty concentrations of both nelfinavir and M8 were measured in 46 patients enrolled in the COPHAR 1-ANRS 102 study. Blood samples were taken at a first visit (one sample before drug administration and four samples at fixed times after) and at a second visit 1 to 3 months later (one before and one 3 h after drug administration). The data from both visits on nelfinavir and M8 were modelled jointly in all patients using a population approach. RESULTS A one-compartment model with first-order absorption and elimination best described nelfinavir data, with an additional compartment incorporating a first order rate-constant describing the metabolism of the drug to M8. For nelfinavir, the apparent volume of distribution (V/F ) (95% confidence interval for the mean), was 309 l (185, 516), the absorption rate constant (k(a)) was 0.4 h(-1) (0.2, 0.8), and the apparent clearance (CL/F ) was 37.3 l h(-1) (32, 44). For M8, V(m) /(Fk(m)) and CL(m)/(Fk(m)) were 866 l h(-1) (351, 2161) and 1670 l (965, 2894), respectively. The interindividual variabilities were 34.9%, 34.3% and 62.2% for V/F, CL/F and CL(m)/(Fk(m)), respectively. The interoccasion variability was 27.8% for CL/F. The mean half-lives were 05.38 h and 00.44 h for nelfinavir and M8, respectively. Significant but opposite effects of comedication with zidovudine were found on nelfinavir CL/F and M8 CL(m)/(Fk(m)), but they were not considered to be clinically relevant. CONCLUSIONS A joint model was found to describe adequately nelfinavir and M8 concentrations and was used to estimate pharmacokinetic parameters for M8. The model can be used to build reference pharmacokinetic profiles for therapeutic drug monitoring of the drug.
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Affiliation(s)
- X Panhard
- INSERM U738, Department of Epidemiology, Biostatistics and Clinical research, AP-HP, Bichat University Hospital, Paris, France.
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Goujard C, Legrand M, Panhard X, Diquet B, Duval X, Peytavin G, Vincent I, Katlama C, Leport C, Bonnet B, Salmon-Céron D, Mentré F, Taburet AM. High variability of indinavir and nelfinavir pharmacokinetics in HIV-infected patients with a sustained virological response on highly active antiretroviral therapy. Clin Pharmacokinet 2006; 44:1267-78. [PMID: 16372824 DOI: 10.2165/00003088-200544120-00005] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
OBJECTIVES To describe plasma concentrations of indinavir alone or combined with ritonavir, and of nelfinavir and its active metabolite M8, and to measure their variabilities in HIV-infected patients treated with a stable antiretroviral regimen and experiencing a sustained virological response for at least 12 months. PATIENTS AND METHODS In this prospective trial, blood samples were drawn during a 6-hour time interval between two doses at enrolment to assess protease inhibitor (PI) pharmacokinetic parameters, and 4 months later to assess plasma trough and peak concentrations. Safety and adherence assessments and laboratory data were collected during an 8-month period. PI pharmacokinetic characteristics were analysed using a non-compartmental approach. Inter- and intrapatient variabilities were estimated using a linear mixed-effect model. The impact of different covariates on plasma trough concentrations was investigated. Eighty-eight patients were analysed: 42 treated with indinavir and 46 with nelfinavir. RESULTS The interquartile range (IQR) of the plasma trough concentration corrected for the sampling time (Ccalc) was 116-374 microg/L for indinavir alone and 163-508 microg/L for indinavir/ritonavir. Ritonavir significantly increased indinavir elimination half-life and plasma exposure. For nelfinavir, the IQR of Ccalc was 896-2059 microg/L for three-times-daily administration and 998-2124 microg/L for twice-daily administration. Variabilities were high for both PIs. Intrapatient variability for indinavir alone (and indinavir + ritonavir) was 76% (107%) and interpatient variability was 58% (10%) in adherent patients. Intrapatient variability for nelfinavir three times daily (and twice daily) was 41% (74%) and interpatient variability was 62% (50%). Intrapatient variability was lowered in patients with a high adherence level. CONCLUSION Although performed in a homogeneous population, this study documented a high interpatient but also intrapatient variability of indinavir and nelfinavir pharmacokinetics, which should be taken into account when interpreting therapeutic drug monitoring. Once patients have reached a sustained virological response, plasma PI monitoring may have a limited impact.
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Affiliation(s)
- Cécile Goujard
- Internal Medicine Unit, Bicêtre University Hospital, AP-HP, Kremlin Bicêtre, France.
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Dirson G, Fernandez C, Hindlet P, Roux F, German-Fattal M, Gimenez F, Farinotti R. Efavirenz does not interact with the ABCB1 transporter at the blood-brain barrier. Pharm Res 2006; 23:1525-32. [PMID: 16779703 DOI: 10.1007/s11095-006-0279-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2005] [Accepted: 02/24/2006] [Indexed: 01/11/2023]
Abstract
PURPOSE This work characterizes the interactions between efavirenz (EFV) and P-glycoprotein (P-gp/ABCB1) at the blood-brain barrier (BBB) and predicts the possible consequences on the brain uptake of coadministered P-gp substrates. METHODS The uptake of EFV was measured in whole brains of rat and mdr1a-/- and mdr1a+/+ mice, and in GPNT cells (rat brain endothelial cell line) with and without P-gp inhibitors (PSC833, S9788, Quinidine). The effect of a single dose or multiple doses of EFV on the P-gp functionality was evaluated in vivo and in vitro by measuring the brain and cell uptake of digoxin, completed by the analysis of the P-gp expression at the rat BBB after repeated administrations of EFV. RESULTS Inhibition of P-gp did not alter the uptake of EFV in rat brain and GPNT cells. The EFV brain/plasma ratio in mdr1a-/- mice, lacking the expression of P-gp, was not different from that in mdr1a+/+ mice. Moreover, a single dose of EFV did not modify the uptake of digoxin in rat brain and GPNT cells. Finally, the 3-day exposure of GPNT cells to EFV did not have any effect on the uptake of digoxin. Similarly, the 7-day treatment with EFV did not change the uptake of digoxin in rat brain nor the expression of P-gp at the BBB. CONCLUSION EFV is strongly distributed in the brain, but is neither a substrate nor an inhibitor of the P-gp at the blood-brain barrier. On the other hand, EFV did not induce P-gp, allowing to sustain the brain accumulation of associated P-gp substrates such as protease inhibitors. These findings make EFV suitable for combinations circumventing the brain HIV-1 residency.
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Affiliation(s)
- Grégoire Dirson
- Clinical Pharmacy Unit (EA 2706; Barrières et passage des medicaments), University of Paris-Sud XI, 5 rue Jean-Baptiste Clément, Châtenay-Malabry, 92296, France
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16
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Pereira EA, Micke GA, Tavares MFM. Determination of antiretroviral agents in human serum by capillary electrophoresis. J Chromatogr A 2005; 1091:169-76. [PMID: 16395807 DOI: 10.1016/j.chroma.2005.07.031] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this work, a simple and rapid electrokinetic chromatography method for the simultaneous separation of different protease inhibitors (indinavir, ritonavir, saquinavir, nelfinavir), nucleoside reverse transcriptase inhibitors (stavudine, zidovudine, didanosine) and non-nucleoside reverse transcriptase inhibitors (nevirapine, efavirenz) was developed. The analyses were performed in a 75 microm i.d. uncoated fused-silica capillary with 48.5 cm length (effective length of 40 cm) using a running buffer consisting of 20 mmol L(-1) sodium dodecyl sulfate, 10 mmol L(-1) sodium tetraborate, 30% acetonitrile and 5% ethanol. Samples were injected hydrodynamically by applying 50 mbar pressure during 6 s. All analytes were separated within 10 min with a voltage of 20 kV. The proposed method was validated for zidovudine, didanosine and efavirenz in human serum. Serum samples were prepared using a solid-phase extraction procedure (Waters Oasis HLB cartridges). For quantitative purposes, stavudine was chosen as the internal standard (IS). Method validation parameters were determined revealing good migration time repeatability (<0.7% RSD) and peak area repeatability (<1.2% RSD). Intra- and inter-day precisions were less than 1.7% and 4.4% RSD, respectively. Matrix matching analytical curves for each drug were linear in the 1.0-20.0 microg mL(-1) interval (r > 0.998). Limits of detection (LOD) were in range of 0.3-0.5 microg mL(-1). The extraction recoveries were higher than 90% with exception of efavirenz, which was 77.4%. Based on the performance characteristics, the proposed method was found suitable for the determination of zidovudine, didanosine and efavirenz in serum samples.
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Affiliation(s)
- Elisabete A Pereira
- Institute of Chemistry, University of Sao Paulo, P.O. Box 26077, 05513-970 Sao Paulo, SP, Brazil.
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17
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Brendel K, Legrand M, Taburet AM, Baron G, Goujard C, Mentré F. Population pharmacokinetic analysis of indinavir in HIV-infected patient treated with a stable antiretroviral therapy. Fundam Clin Pharmacol 2005; 19:373-83. [PMID: 15910662 DOI: 10.1111/j.1472-8206.2005.00315.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The objectives of this study were to build a population pharmacokinetic model that describe plasma concentrations of indinavir in human immunodeficiency virus (HIV)-infected patients with sustained virological response under a stable antiretroviral combination, and to characterize the effect of covariates and co-medications on indinavir pharmacokinetics. Data were obtained from 45 patients who received different dosages of indinavir: either indinavir alone t.i.d. (mostly 800 mg), either indinavir b.i.d. (mostly 800 mg) with a booster dose of 100 mg of ritonavir. Patients were required to have a baseline plasma HIV RNA <200 copies/mL and to have unchanged antiretroviral treatment for 6 months. Indinavir concentrations were measured at a first visit (one sample before drug administration and five after) and at a second visit 3 months later (before and 1 or 3 h after drug administration). A one-compartment model with first-order absorption and first-order elimination best described indinavir pharmacokinetics. For patients treated with indinavir alone, absorption rate constant was estimated to be 0.43/h, and oral clearance Cl/F was 33 L/h. For patients treated with indinavir plus ritonavir these estimates were 0.25/h and 19 L/h, respectively. Cl/F was found to increase by 1.45-fold in men and by 1.18-fold in patients also receiving zidovudine. Oral volume of distribution (V/F) was 24 L. The inter-individual and intra-individual variability were 117 and 205% for V/F, 42 and 58% for Cl/F, respectively. This population analysis in patients with sustained virological response, quantified the effect of ritonavir on the absorption rate constant and on the clearance of indinavir, showed an increase of Cl/F in men and can be used to draw reference curve for therapeutic drug monitoring.
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Affiliation(s)
- Karl Brendel
- INSERM E0357, Department of Epidemiology, Biostatistics and Clinical Research, AP-HP, Bichat University Hospital, Paris, France.
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18
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Tribut O, Verdier MC, Arvieux C, Allain H, Michelet C, Bentué-Ferrer D. Simultaneous Quantitative Assay of Atazanavir and 6 Other HIV Protease Inhibitors by Isocratic Reversed-Phase Liquid Chromatography in Human Plasma. Ther Drug Monit 2005; 27:265-9. [PMID: 15905793 DOI: 10.1097/01.ftd.0000162230.83188.32] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Several liquid chromatography methods for assay of antiretroviral drugs in human plasma have been described, but none included atazanavir. The authors describe a user-friendly, validated, and rapid technique, derived from a procedure the authors have already published, allowing simultaneous quantification of amprenavir, indinavir, lopinavir, nelfinavir (and its M8 metabolite), ritonavir, saquinavir, efavirenz, and nevirapine. Assays were performed after diethyl ether liquid-liquid extraction from 250 microL plasma samples. Chromatographic separation was achieved on an X-TERRA column using a 58% water (with 3 mM pyrrolidine) and 42% acetonitrile mobile phase; 240 nm ultraviolet wavelength was used for atazanavir detection. This method has been in routine use in our laboratory for antiretroviral drug monitoring and now allows quantitative assay of a novel HIV protease inhibitor, atazanavir, with satisfactory intra- and interassay precision (CV<12%).
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Affiliation(s)
- Olivier Tribut
- Laboratoire de Pharmacologie, Hôpital de Pontchaillou, 35033 Rennes, France.
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19
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Pèlerin H, Compain S, Duval X, Gimenez F, Bénech H, Mabondzo A. Development of an assay method for the detection and quantification of protease and non-nucleoside reverse transcriptase inhibitors in plasma and in peripherical blood mononuclear cells by liquid chromatography coupled with ultraviolet or tandem mass spectrometry detection. J Chromatogr B Analyt Technol Biomed Life Sci 2005; 819:47-57. [PMID: 15797520 DOI: 10.1016/j.jchromb.2005.01.024] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2004] [Accepted: 01/21/2005] [Indexed: 11/23/2022]
Abstract
We present a simple chromatographic method to detect and quantify protease inhibitors (PI), metabolites and non-nucleoside reverse transcriptase inhibitors (NNRTIs) in human plasma of HIV-1 infected patients and in peripheral blood mononuclear cells (PBMCs) using either liquid chromatography coupled with ultraviolet (LC-UV) or liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). A solid-liquid extraction was carried out on 500 microl of plasma as pre-treatment. Calibration curve ranges were from 50 (100) to 5000 ng/ml (indinavir). PBMC pellets from 7 ml of blood were lysed with methanol/tris with a calibration curve ranging from 0.25 to 250 ng/pellet. Simple modifications in the mobile phase composition (slight increase of ammonium acetate concentration and addition of methanol for LC-UV) easily linked the two analytical systems.
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Affiliation(s)
- Hélène Pèlerin
- CEA, Service de Pharmacologie et d'Immunologie, DSV/DRM, 91191 Gif sur Yvette Cedex, France
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20
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Koal T, Burhenne H, Römling R, Svoboda M, Resch K, Kaever V. Quantification of antiretroviral drugs in dried blood spot samples by means of liquid chromatography/tandem mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2005; 19:2995-3001. [PMID: 16193530 DOI: 10.1002/rcm.2158] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
For the first time approved antiretroviral drugs, i.e. protease inhibitors (PI) and non-nucleoside reverse transcriptase inhibitors (NNRTI), were quantified in dried blood spots (DBS) from HIV/AIDS patient whole blood samples as the basis for therapeutic drug monitoring (TDM) by a robust simultaneous liquid chromatography/tandem mass spectrometry (LC/MS/MS) method. This study included seven PI (amprenavir, nelfinavir, indinavir, lopinavir, saquinavir, ritonavir, atazanavir) and two NNRTI (nevirapine, efavirenz). LC/MS/MS coupling was realized using a Phenomenex Synergy Max RP LC column (150 x 2 mm, 4 micro) in combination with a tandem mass spectrometer (API 2000, Applied Biosystems/MDS Sciex Concord) operating in positive and negative multiple reaction monitoring (MRM) mode with reserpine as internal standard. DBS samples were punched out and extracted with 50:50 MeOH/0.2 M ZnSO4 (v/v) as extraction reagent. The method performance data for the drugs in DBS like limits of detection (LOD, 8-70 ng/mL), lower limits of quantification (LLOQ, 41-102 ng/mL), linearity (R2, 0.9981-0.9999), linear concentration ranges (41-10.000 ng/mL), accuracies (92-113%), recoveries (62-94%), and ion suppression were investigated and are comparable to data obtained from human plasma, which is the current standard matrix for TDM of PI and NNRTI. In this case, off-line plasma sample preparation was performed by means of simple protein precipitation with 80:20 methanol/0.2 M ZnSO4 (v/v) as precipitation reagent. Significant correlations between real patient plasma and DBS were obtained for samples containing lopinavir, atazanavir, ritonavir, saquinavir, and efavirenz. DBS preparation as sampling alternative is well suited and practicable for TDM minimizing the high infection risk of HIV/AIDS samples and may facilitate sample mailing.
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Affiliation(s)
- Therese Koal
- Medical School Hannover, Institute of Pharmacology, Carl-Neuberg-Strasse 1, D-30625 Hannover, Germany.
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21
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Takahashi M, Yoshida M, Oki T, Okumura N, Suzuki T, Kaneda T. Conventional HPLC Method Used for Simultaneous Determination of the Seven HIV Protease Inhibitors and Nonnucleoside Reverse Transcription Inhibitor Efavirenz in Human Plasma. Biol Pharm Bull 2005; 28:1286-90. [PMID: 15997115 DOI: 10.1248/bpb.28.1286] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We developed a simple HPLC method for the simultaneous quantitative determination of seven HIV protease inhibitors: amprenavir (APV), atazanavir (ATV), indinavir (IDV), lopinavir (LPV), nelfinavir (NFV), ritonavir (RTV), saquinavir (SQV), and a nonnucleoside reverse transcription inhibitor, efavirenz (EFV). This method involves a rapid liquid-liquid drug extraction from plasma, the use of an isocratic elution on a reversed-phase C18 column, and an ultraviolet detection at a single wavelength (205 nm). The mobile phase consisted of 39% 50 mM phosphate buffer (pH 5.9), 22% methanol and 39% acetonitrile. Forty-eight samples could be measured in one day since the runtime of one sample is 30 min. The assay has been validated over a concentration range of 0.05 to 12.20 microg/ml for APV, 0.09 to 12.05 microg/ml for ATV, 0.05 to 12.01 microg/ml for IDV, 0.12 to 12.36 microg/ml for LPV, 0.18 to 12.20 microg/ml for NFV, 0.12 to 12.33 microg/ml for RTV, 0.12 to 12.06 microg/ml for SQV, and 0.05 to 12.17 microg/ml for EFV. Calibration curves were linear in the described concentration ranges. The average accuracy ranged from 97.2 to 106.8%. Both the interday and intraday coefficients of variation for all drugs tested were less than 8.5%. This method provides a simple, accurate, and precise method for the therapeutic drug monitoring of the seven protease inhibitors and EFV in clinical routine use.
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Affiliation(s)
- Masaaki Takahashi
- Department of Pharmacy, National Hospital Organization Nagoya Medical Center (Tokai Area Central Hospital for AIDS Treatment and Research), Aichi, Japan
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22
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Le Tiec C, Barrail A, Goujard C, Taburet AM. Clinical Pharmacokinetics and Summary of Efficacy and Tolerability of Atazanavir. Clin Pharmacokinet 2005; 44:1035-50. [PMID: 16176117 DOI: 10.2165/00003088-200544100-00003] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The efficacy of HIV-1 protease inhibitors (PIs) as part of highly active antiretroviral therapy is now well established and has provided benefits to many patients with HIV infection. Atazanavir is a new azapeptide PI compound that was recently approved in the US and Europe. Atazanavir is recommended in combination with other antiretroviral agents for the treatment of HIV-1 infection. Atazanavir is rapidly absorbed and administration of a single dose of atazanavir with a light meal resulted in a 70% increase in area under the plasma concentration-time curve (AUC); therefore atazanavir should be taken with food. Atazanavir is 86% bound to human serum protein independently of concentration. Concentration in body fluids appeared to be lower than plasma concentration. Like other PIs, atazanavir is extensively metabolised by hepatic cytochrome P450 (CYP) 3A isoenzymes. The mean terminal elimination half-life in healthy volunteers was approximately 7 hours at steady state following administration of atazanavir 400 mg daily with a light meal. When atazanavir 300 mg was coadministered with ritonavir 100 mg on a once-daily dosage regimen, atazanavir AUC from 0 to 24 hours and minimum plasma concentration were increased by 3- to 4-fold and approximately 10-fold, respectively, compared with atazanavir 300 mg alone. Therefore, ritonavir boosted atazanavir regimen (ritonavir 100 mg and atazanavir 300 mg once daily) is increasingly favoured in some patients. Efavirenz, a potent CYP3A inducer, decreased atazanavir concentrations by 75% and, unexpectedly, tenofovir, a nucleotide reverse transcriptase inhibitor, decreased atazanavir concentrations by 25%. Average predose concentrations in HIV-infected patients who received atazanavir 400mg once daily were 273 ng/mL, which was believed to be several-fold higher than protein-binding corrected 50% inhibitory concentration of wild-type viruses. In HIV-infected patients who received once-daily ritonavir (100mg) boosted atazanavir (300 mg), mean (+/-SD) trough concentration was 862 (+/-838) ng/mL. Several clinical trials showed the efficacy of atazanavir 400 mg once daily with a nucleoside analogue backbone in antiretroviral-naive patients. The atazanavir 300/ritonavir 100 mg once-daily combination coadministered with other antiretrovirals showed the efficacy of this strategy in patients receiving efavirenz or in moderately antiretroviral-experienced HIV-infected patients. Recommended once-daily doses of atazanavir taken with food are either 400 mg or 300 mg in combination with low dose ritonavir (100 mg) in moderately antiretroviral-experienced patients. Major advantages of atazanavir to date are its simplicity of administration (once-daily administration) and its less undesirable effect on the lipid profiles in patients.
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Affiliation(s)
- Clotilde Le Tiec
- Clinical Pharmacy Department, Hôpital Bicêtre, Assistance Publique Hôpitaux de Paris (AP-HP), Paris, France
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23
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Kaul N, Agrawal H, Paradkar A, Mahadik K. Stability indicating high-performance thin-layer chromatographic determination of nelfinavir mesylate as bulk drug and in pharmaceutical dosage form. Anal Chim Acta 2004. [DOI: 10.1016/j.aca.2003.09.058] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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24
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Droste JAH, Verweij-Van Wissen CPWGM, Burger DM. Simultaneous determination of the HIV drugs indinavir, amprenavir, saquinavir, ritonavir, lopinavir, nelfinavir, the nelfinavir hydroxymetabolite M8, and nevirapine in human plasma by reversed-phase high-performance liquid chromatography. Ther Drug Monit 2003; 25:393-9. [PMID: 12766571 DOI: 10.1097/00007691-200306000-00023] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
A reversed-phase high-performance liquid chromatography method for the simultaneous quantitative determination of the currently available HIV protease inhibitors amprenavir, indinavir, lopinavir, nelfinavir, ritonavir, saquinavir, the active nelfinavir metabolite M8, and the nonnucleoside reverse transcriptase inhibitor nevirapine in human plasma is described. The method involved liquid-liquid extraction from plasma, followed by high-performance liquid chromatography with an OmniSpher 5 C18 column and ultraviolet detection set at a wavelength of 215 nm for the protease inhibitors and 280 nm for nevirapine. The runtime was 25 minutes. The assay has been validated over the concentration range of 0.05 to 30 mg/L for indinavir, nelfinavir, ritonavir, and saquinavir, 0.07 to 30 mg/L for amprenavir and lopinavir, and 0.05 to 15 mg/L for M8 and nevirapine. This method proved to be simple, accurate, and precise and is useful for the therapeutic drug monitoring of protease inhibitors and the nonnucleoside reverse transcriptase inhibitor nevirapine on a routine basis.
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Affiliation(s)
- J A H Droste
- Deparment of Clinical Pharmacy, University Medical Center Nijmegen, Nijmegen, The Netherlands.
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25
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Rentsch KM. Sensitive and specific determination of eight antiretroviral agents in plasma by high-performance liquid chromatography-mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 788:339-50. [PMID: 12705974 DOI: 10.1016/s1570-0232(03)00039-4] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Therapeutic drug monitoring of antiretroviral drugs has become more and more important. Therefore, a highly specific method is presented, which is capable of quantifying the different proteinase inhibitors (amprenavir, indinavir, lopinavir, nelfinavir, ritonavir, saquinavir) and non-nucleoside reverse transcriptase inhibitors (efavirenz, nelfinavir). The antiretroviral agents were separated and detected using LC-MS and atmospheric pressure chemical ionization. After solid-phase extraction, the antiretrovirals were separated within 21 min using gradient elution. The calibration range of each drug was linear including the expected minimum and maximum concentrations measured in plasma after the administration of the different drugs. All within-day and between-day coefficients of variation were below 10% and the recovery rates were between 34.8 and 124%. The respective quantification limits were 1 microg/l (indinavir), 10 microg/l (amprenavir, efavirenz), 50 microg/l (saquinavir), 90 microg/l (nelfinavir), 200 microg/l (nevirapine, ritonavir) and 250 microg/l (lopinavir).
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Affiliation(s)
- Katharina M Rentsch
- Institute of Clinical Chemistry, University Hospital Zürich, Rämistrasse 100, CH-8091, Zürich, Switzerland.
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26
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Burhenne J, Riedel KD, Martin-Facklam M, Mikus G, Haefeli WE. Highly sensitive determination of saquinavir in biological samples using liquid chromatography-tandem mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 784:233-42. [PMID: 12505771 DOI: 10.1016/s1570-0232(02)00803-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
A selective and sensitive method for the determination of the HIV protease inhibitor saquinavir in human plasma, saliva, and urine using liquid-liquid extraction and LC-MS-MS has been developed, validated, and applied to samples of a healthy individual. After extraction with ethyl acetate, sample extracts were chromatographed isocratically within 5 min on Kromasil RP-18. The drug was detected with tandem mass spectrometry in the selected reaction monitoring mode using an electrospray ion source and 2H(5)-saquinavir as internal standard. The limit of quantification was 0.05 ng/mL. The accuracy of the method varied between -1 and +10% (SD within-batch) and the precision ranged from +4 to +10% (SD batch-to-batch). The method is linear at least within 0.05 and 87.6 ng/mL. After a regular oral dose (600 mg) saquinavir concentrations were detectable for 48 h in plasma and were well correlated with saliva concentrations (r(2)=0.9348, mean saliva/plasma ratio 1:15.1). The method is well suited for low saquinavir concentrations in different matrices.
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Affiliation(s)
- Jürgen Burhenne
- Department of Internal Medicine VI, Bergheimer Strasse 58, University of Heidelberg, D-69115, Heidelberg, Germany.
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Janoly A, Bleyzac N, Favetta P, Gagneu MC, Bourhis Y, Coudray S, Oger I, Aulagner G. Simple and rapid high-performance liquid chromatographic method for nelfinavir, M8 nelfinavir metabolite, ritonavir and saquinavir assay in plasma. J Chromatogr B Analyt Technol Biomed Life Sci 2002; 780:155-60. [PMID: 12383491 DOI: 10.1016/s1570-0232(02)00465-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A simple reversed-phase liquid chromatographic method has been developed to determine protease inhibitors concentrations in plasma. Plasma samples (250 micro l) containing protease inhibitors were prepared by a simple deproteinization (recovery: 92, 91, 91 and 90.5% for ritonavir, saquinavir, nelfinavir and M8 nelfinavir metabolite, respectively). Chromatography was accomplished using a Hypersil octadecylsilyl column (100 x 4.6 mm I.D.) and a mobile phase composed of acetonitrile, tetrahydrofuran and dihydrogenophosphate buffer (pH 4) (32:10:58, v/v). Ultraviolet detection at 210 nm was used. The limit of detection was 200 ng/ml for ritonavir, saquinavir, nelfinavir and M8 nelfinavir metabolite. Calibration curves were linear up to 20000 ng/ml, with correlation coefficients better than 0.997 for all compounds. Intra- and inter-day coefficients of variation of the assay were <or=6% for all compounds. This method was used to analyse protease inhibitors plasma concentrations after oral administration within the framework of therapeutic drug monitoring and pharmacokinetic studies in AIDS patients.
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Affiliation(s)
- A Janoly
- Pharmacy Department, Debrousse Hospital, 29 Rue Soeur Bouvier, 69005, Lyon, France
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28
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Chi J, Jayewardene AL, Stone JA, Motoya T, Aweeka FT. Simultaneous determination of five HIV protease inhibitors nelfinavir, indinavir, ritonavir, saquinavir and amprenavir in human plasma by LC/MS/MS. J Pharm Biomed Anal 2002; 30:675-84. [PMID: 12367693 DOI: 10.1016/s0731-7085(02)00357-6] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A sensitive and rapid liquid chromatography tandem mass spectrometry (LC-MS-MS) method has been developed to measure the levels of five HIV protease inhibitors nelfinavir (NFV), indinavir (IDV), ritonavir (RTV), saquinavir (SQV) and amprenavir (APV) in human plasma. The analytes and internal standard are isolated from plasma by a simple acetonitrile precipitation of plasma proteins followed by centrifugation. LC-MS-MS in positive mode used pairs of ions at m/z of 568.4/330.0, 614.3/421.2, 720.9/296.0, 671.1/570.2 and 505.9/245.0 for NFV, IDV, RTV, SQV and APV, respectively and 628/421 for the internal standard. Two 1/x weighted linear calibration curves for each analyte were established for quantitation with the low curve ranging from 5 to 1000 ng/ml and while the high curve ranging from 1000 to 10,000 ng/ml. Mean inter- and intra-assay coefficients of variation (CVs) over the ranges of the standard curves were less than 10%. The overall recovery of NFV, IDV, RTV, SQV and APV were 88.4, 91.4, 92.2, 88.9 and 87.6%, respectively.
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Affiliation(s)
- Jingduan Chi
- Department of Clinical Pharmacy, Drug Research Unit, School of Pharmacy, University of California, San Francisco, CA 94143, USA.
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Tribut O, Arvieux C, Michelet C, Chapplain JM, Allain H, Bentué-Ferrer D. Simultaneous quantitative assay of six HIV protease inhibitors, one metabolite, and two non-nucleoside reverse transcriptase inhibitors in human plasma by isocratic reversed-phase liquid chromatography. Ther Drug Monit 2002; 24:554-62. [PMID: 12142642 DOI: 10.1097/00007691-200208000-00015] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
A rapid (less than 30 min), sensitive, and specific liquid chromatography method for simultaneous assay of nine antiretroviral drugs in human plasma is described. This technique allows therapeutic drug monitoring of six approved protease inhibitors (amprenavir, indinavir, lopinavir, nelfinavir, ritonavir, and saquinavir) and two approved non-nucleoside reverse transcriptase inhibitors (efavirenz and nevirapine). Assays were performed after diethyl ether liquid-liquid extraction from 250-microL plasma samples. Chromatographic separation was achieved on an X-TERRA (Waters; Saint Quentin, France) column using a 58% water (with 3 mmol/L pyrrolidine) and 42% acetonitrile mobile phase. Three ultraviolet wavelengths were used for detection with a diode array detector. This method allowed quantitative assay of all nine antiretroviral drugs within a concentration range of 25 ng/mL to 9000 ng/mL. The method has been validated extensively and has been in routine use in our laboratory for several months for drug monitoring in plasma samples from patients treated with antiretroviral drugs.
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Affiliation(s)
- Olivier Tribut
- Laboratoire de Pharmacologie Biologique, Hôpital de Pontchaillou, Rennes, France.
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Rezk NL, Tidwell RR, Kashuba ADM. Simple and rapid quantification of the non-nucleoside reverse transcriptase inhibitors nevirapine, delavirdine, and efavirenz in human blood plasma using high-performance liquid chromatography with ultraviolet absorbance detection. J Chromatogr B Analyt Technol Biomed Life Sci 2002; 774:79-88. [PMID: 12052725 DOI: 10.1016/s1570-0232(02)00210-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A simple reversed-phase high-performance liquid chromatography assay for the simultaneous quantitative determination of three HIV non-nucleoside reverse transcriptase inhibitors (nevirapine, delavirdine, and efavirenz) in human blood plasma is described. The method was validated over the range of 10 ng/ml to 50 microg/ml for nevirapine, 25 ng/ml to 25 microg/ml for delavirdine, and 10 ng/ml to 10 microg/ml for efavirenz. The method is accurate (average accuracies over eight concentrations ranging from 87.3 to 113%), and precise (within-day and between-day precision measures ranging from 0.12 to 7.9% and 0.26 to 5.9%, respectively). All three non-nucleoside reverse transcriptase inhibitors proved to be stable under various conditions. Due to its simplicity, this assay can readily be used for investigational or clinical monitoring of plasma concentrations.
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Affiliation(s)
- Naser L Rezk
- Pharmacology Core, Center for AIDS Research, 808 Brinkhouse-Bullitt, CB #7525, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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31
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Matthews CZ, Woolf EJ, Mazenko RS, Haddix-Wiener H, Chavez-Eng CM, Constanzer ML, Doss GA, Matuszewski BK. Determination of efavirenz, a selective non-nucleoside reverse transcriptase inhibitor, in human plasma using HPLC with post-column photochemical derivatization and fluorescence detection. J Pharm Biomed Anal 2002; 28:925-34. [PMID: 12039635 DOI: 10.1016/s0731-7085(01)00709-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Methods for the quantitative determination of efavirenz in human plasma and the qualitative assessment of the stereochemical integrity of efavirenz in post-dose human plasma samples are described. After the addition of an internal standard, plasma samples were extracted with hexane-methylene chloride (65/35, v/v%). The extracts were evaporated to dryness and reconstituted in mobile phase. Upon exposure to UV light, the analyte was found to form fluorescent products; the major fluorescent product was isolated and identified as a substituted quinoline. Thus, the plasma extracts were analyzed via HPLC with post-column photochemical derivatization and fluorescence detection. Reverse phase chromatography was used for the quantitative assay, whereas chromatography with a column containing a chiral stationary phase (dinitrobenzoyl leucine) was used for the stereochemical assessment. The quantitative assay has been validated in the concentration range of 50-1000 ng/ml using 0.5 ml samples. Analyte recovery was better than 89% at all points on the standard curve. Intra-day precision was better than 5% C.V., while accuracy was between 95 and 104% of nominal over the range of the assay. The selective detection method reduces the likelihood of interference by co-administered medications or endogenous species. The stereochemical configuration of efavirenz was confirmed to remain intact in post-dose human plasma samples. The quantitative method has been successfully utilized to support a study in which a possible drug interaction between co-administered HIV protease inhibitors and efavirenz was evaluated.
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Affiliation(s)
- C Z Matthews
- Department of Drug Metabolism, Merck Research Laboratories, West Point, PA 19486, USA
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32
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Abstract
The interest in therapeutic drug monitoring (TDM) of antiretroviral drugs is growing rapidly. For the protease inhibitors, and to a lesser extent for the non-nucleoside reverse transcriptase inhibitors, relationships between plasma drug concentrations and their efficacy and toxicity have been identified. Furthermore, the pharmacokinetics of especially the protease inhibitors vary widely between patients, suggesting a role for TDM to individualize antiretroviral therapy. Recently, randomized, prospective clinical trials evaluating the role of TDM in the management of HIV-1-infected patients showed promising results. However, there are still many questions to be answered before large-scale introduction of TDM can be justified (e.g., which pharmacokinetic parameter should be optimized, and what is the minimal effective concentration). This review summarizes the basis for TDM of antiretroviral drugs and discusses the problems and prospects of this potential tool in the care for HIV-1-infected individuals.
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Affiliation(s)
- Rolf P G Van Heeswijk
- International Antiviral Therapy Evaluation Center, Academic Medical Center, Amsterdam, The Netherlands.
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Titier K, Lagrange F, Péhourcq F, Edno-Mcheik L, Moore N, Molimard M. High-performance liquid chromatographic method for the simultaneous determination of the six HIV-protease inhibitors and two non-nucleoside reverse transcriptase inhibitors in human plasma. Ther Drug Monit 2002; 24:417-24. [PMID: 12021635 DOI: 10.1097/00007691-200206000-00015] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A selective and sensitive high-performance liquid chromatographic (HPLC) method has been developed for the determination of the six human immunodeficiency virus (HIV)-protease inhibitors (amprenavir, indinavir, lopinavir, nelfinavir, ritonavir, and saquinavir) and the non-nucleoside reverse transcriptase inhibitors (efavirenz and nevirapine) in a single run. After a liquid-liquid extraction with diethyl ether, the six protease inhibitors and the two non-nucleoside reverse transcriptase inhibitors are separated on a Stability RP18 column eluted with a gradient of acetonitrile and phosphate buffer 50 mmol/L pH 5.65. A sequential ultraviolet detection (5-minute sequence set at 240 nm for nevirapine acquisition, 22-minute sequence set at 215 nm for other antiretroviral drugs acquisition followed by a sequence set at 260 nm for internal standard acquisition) allowed for simultaneous quantitation of the six protease inhibitors, nevirapine, and efavirenz. Calibration curves were linear in the range 100 ng/mL to 10,000 ng/mL. The limit of quantitation was 50 ng/mL for all drugs except nevirapine (100 ng/mL). Average accuracy at four concentrations ranged from 88.2% to 110.9%. Both interday and intraday coefficients of variation were less than 11% for all drugs. The extraction recoveries were greater than 62%. This method is simple and shows a good specificity with respect to commonly co-prescribed drugs. This method allows accurate therapeutic monitoring of amprenavir, indinavir, lopinavir, nelfinavir, ritonavir, saquinavir, efavirenz, and nevirapine.
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Affiliation(s)
- Karine Titier
- Department of Clinical Pharmacology and Toxicology, University Victor Ségalen, Pellegrin Hospital, Place Amélie Raba-Léon, 33076 Bordeaux cedex, France
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34
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Cheng CL, Chou CH, Hu OYP. Determination of delavirdine in very small volumes of plasma by high-performance liquid chromatography with fluorescence detection. J Chromatogr B Analyt Technol Biomed Life Sci 2002; 769:297-303. [PMID: 11996495 DOI: 10.1016/s1570-0232(02)00015-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Delavirdine is a newly developed anti-HIV-1 drug for AIDS therapy. This study describes a sensitive high-performance liquid chromatographic method for the determination of delavirdine in 50 microl of plasma. Samples were deproteinized with 150 microl of a solution of internal standard (cisapride 10 microg/ml) in acetonitrile. An aliquot of the supernatant was injected onto the column. HPLC separation was achieved on a C18 column with the mobile phase of acetonitrile-50 mM sodium dihydrogen phosphate (60:40, v/v) at a flow-rate of 1 ml/min. The eluants were measured by fluorescence detection with excitation at 295 nm and emission filtration at 425 nm. The retention time was about 5.3 min for delavirdine and 6.5 min for cisapride. The specificity was demonstrated, as there were no interferences from plasma samples of different batches in the regions of peak interest. Calibration curves were linear from 25 to 25000 ng/ml. The limit of quantitation was 25 ng/ml. The within- and between-day precision (C.V.) was 9.3%, or less, and the accuracy was within 9.2% of the nominal concentration. The small sample volume needed is especially advantageous for the application both in pharmacokinetic studies in HIV-infected adults and pediatric patients, and in small animals, where limited samples are available.
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Affiliation(s)
- Ching-Ling Cheng
- Department of Pharmacy, Chia-Nan University of Pharmacy and Science, Tainan, Taiwan.
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Campanero MA, Escolar M, Arangoa MA, Sádaba B, Azanza JR. Development of a chromatographic method for the determination of saquinavir in plasma samples of HIV patients. Biomed Chromatogr 2002; 16:7-12. [PMID: 11816005 DOI: 10.1002/bmc.102] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A simple, sensitive and reproducible high-performance liquid chromatographic method for detecting and quantifying saquinavir in human plasma is described. Verapamil was used as internal standard. The method employes a single liquid-liquid extraction step with tert-butil methyl ether followed by chromatography on a Lichrospher 60 Select B C8 reversed-phase column. Ultraviolet detection was used to identify the compounds of interest. The quantitation limit of saquinavir was 1 ng/mL and only 0.5 mL of plasma sample was required for the determination. The average saquinavir recoveries over a concentration range of 2.5-500 ng/mL ranged from 86 to 95%. Precision and accuracy did not exceed 5%.
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Affiliation(s)
- M A Campanero
- Department of Clinical Pharmacology, Clinica Universitaria de Navarra, Pamplona, Spain.
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Aarnoutse RE, Verweij-van Wissen CP, Underberg WJ, Kleinnijenhuis J, Hekster YA, Burger DM. High-performance liquid chromatography of HIV protease inhibitors in human biological matrices. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2001; 764:363-84. [PMID: 11817038 DOI: 10.1016/s0378-4347(01)00344-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Methods for HPLC analysis of protease inhibitors (PIs) in human biological matrices were reviewed. Assays have been developed for analysis of single PIs or for simultaneous measurement of multiple PIs in plasma-serum, saliva, cerebrospinal fluid and semen. Liquid-liquid extraction was most often applied for sample pretreatment, but solid-phase extraction and protein precipitation were used as well. Reversed-phase or ion-pair chromatography have been used to separate PIs. Detection of PIs should be sensitive enough for quantitation of plasma concentrations below trough levels of single PIs, or below proposed therapeutic thresholds for PIs. The large majority of assays employs UV detection. As the potential for interferences is large, the selectivity of every method should be evaluated properly. The available high-performance liquid chromatography (HPLC) methods have been applied in clinical pharmacokinetic studies and for therapeutic drug monitoring of PIs. Participation in an interlaboratory quality control program is recommended for every laboratory engaged in the bioanalysis of PIs.
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Affiliation(s)
- R E Aarnoutse
- Department of Clinical Pharmacy, University Medical Center Nijmegen, The Netherlands.
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37
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Dailly E, Thomas L, Kergueris MF, Jolliet P, Bourin M. High-performance liquid chromatographic assay to determine the plasma levels of HIV-protease inhibitors (amprenavir, indinavir, nelfinavir, ritonavir and saquinavir) and the non-nucleoside reverse transcriptase inhibitor (nevirapine) after liquid-liquid extraction. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2001; 758:129-35. [PMID: 11486821 DOI: 10.1016/s0378-4347(01)00117-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
A single HPLC assay was developed for therapeutic drug monitoring of 5 HIV protease inhibitors (indinavir, amprenavir, saquinavir, ritonavir, nelfinavir) and a non-nucleoside reverse transcriptase inhibitor (nevirapine) in human plasma. After liquid-liquid extraction in a mixture ethyl acetate-hexane, compounds are separated on a C18 column with a gradient elution of solvent A [acetonitrile and 0.025 M tetramethylammonium perchlorate in 0.2% aqueous trifluoroacetic acid (55:45 (v/v))] and solvent B [methanol and 0.025 M tetramethylammonium perchlorate in 0.2% aqueous trifluoroacetic acid (55:45 (v/v))]. The compounds are detected at various wavelengths: 320 nm (nevirapine), 259 nm (indinavir), 254 nm (amprenavir, nelfinavir, saquinavir) and 239 nm (ritonavir). The intra-day and inter-day precision and accuracy are lower than 15%. The limits of quantitation are 0.05 mg/l (amprenavir), 0.2 mg/l (indinavir, saquinavir, nelfinavir) and 0.4 mg/l (ritonavir, nevirapine). This method which allows to estimate simultaneously plasma levels of protease inhibitors and nevirapine can be used for therapeutic drug monitoring.
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Affiliation(s)
- E Dailly
- Laboratoire de Pharmacologie Clinique, Institut de Biologie, Centre Hospitalier-Universitaire, Nantes, France
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