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Ghasemlou A, Uskoković V, Sefidbakht Y. Exploration of potential inhibitors for SARS-CoV-2 Mpro considering its mutants via structure-based drug design, molecular docking, MD simulations, MM/PBSA, and DFT calculations. Biotechnol Appl Biochem 2023; 70:439-457. [PMID: 35642754 DOI: 10.1002/bab.2369] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 04/21/2022] [Indexed: 11/08/2022]
Abstract
The main protease (Mpro) of SARS-COV-2 plays a vital role in the viral life cycle and pathogenicity. Due to its specific attributes, this 3-chymotrypsin like protease can be a reliable target for the drug design to combat COVID-19. Since the advent of COVID-19, Mpro has undergone many mutations. Here, the impact of 10 mutations based on their frequency and five more based on their proximity to the active site was investigated. For comparison purposes, the docking process was also performed against the Mpros of SARS-COV and MERS-COV. Four inhibitors with the highest docking score (11b, α-ketoamide 13b, Nelfinavir, and PF-07321332) were selected for the structure-based ligand design via fragment replacement, and around 2000 new compounds were thus obtained. After the screening of these new compounds, the pharmacokinetic properties of the best ones were predicted. In the last step, comparative molecular dynamics (MD) simulations, molecular mechanics Poisson-Boltzmann surface area calculations (MM/PBSA), and density functional theory calculations were performed. Among the 2000 newly designed compounds, three of them (NE1, NE2, and NE3), which were obtained by modifications of Nelfinavir, showed the highest affinity against all the Mpro targets. Together, NE1 compound is the best candidate for follow-up Mpro inhibition and drug development studies.
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Affiliation(s)
| | - Vuk Uskoković
- TardigradeNano, LLC, Irvine, California, USA.,Department of Mechanical Engineering, San Diego State University, San Diego, California, USA
| | - Yahya Sefidbakht
- Protein Research Center, Shahid Beheshti University, Tehran, Iran
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Liu Z, Guo X, Guo A, Zhang S, Zou Y, Wang Y, Li X, He W, Pu L, Zhang S, Zeng Q, Cai X, Wang S. HIV protease inhibitor nelfinavir is a potent drug candidate against echinococcosis by targeting Ddi1-like protein. EBioMedicine 2022; 82:104177. [PMID: 35843171 PMCID: PMC9294487 DOI: 10.1016/j.ebiom.2022.104177] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 06/15/2022] [Accepted: 07/04/2022] [Indexed: 11/30/2022] Open
Abstract
Background Alveolar echinococcosis (AE), which is caused by larval Echinococcus multilocularis, is one of the world's most dangerous neglected diseases. Currently, no fully effective treatments are available to cure this disease. Methods In vitro protoscolicidal assay along with in vivo murine models was applied in repurposing drugs against AE. Genome-wide identification and homology-based modeling were used for predicting drug targets. RNAi, enzyme assay, and RNA-Seq analyses were utilized for investigating the roles in parasite survival and validations for the drug target. Findings We identified nelfinavir as the most effective HIV protease inhibitor against larval E. multilocularis. Once-daily oral administration of nelfinavir for 28 days resulted in a remarkable reduction in parasite infection in either immune-competent or immunocompromised mice. E. multilocularis DNA damage-inducible 1 protein (EmuDdi1) is predicted as a target candidate for nelfinavir. We proved that EmuDdi1 is essential for parasite survival and protein excretion and acts as a functionally active protease for this helminth. We found nelfinavir is able to inhibit the proteolytic activity of recombinant EmuDdi1 and block the EmuDdi1-related pathways for protein export. With other evidence of drug efficacy comparison, our results suggest that inhibition of EmuDdi1 is a mechanism by which this HIV proteinase inhibitor mediates its antiparasitic action on echinococcosis. Interpretation This study demonstrates that nelfinavir is a promising candidate for treating echinococcosis. This drug repurposing study proves that the widely prescribed drug for AIDS treatment is potent in combating E. multilocularis infection and thus provides valuable insights into the development of single-drug therapy for highly prevalent co-infection between HIV and helminth diseases. Funding This work was supported by the National Natural Science Foundation of China (31802179), the Natural Science Foundation of Gansu Province, China (No. 21JR7RA027), and the State Key Laboratory of Veterinary Etiological Biology (No. SKLVEB2021YQRC01).
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Bauso LV, Imbesi C, Irene G, Calì G, Bitto A. New Approaches and Repurposed Antiviral Drugs for the Treatment of the SARS-CoV-2 Infection. Pharmaceuticals (Basel) 2021; 14:503. [PMID: 34070359 PMCID: PMC8228036 DOI: 10.3390/ph14060503] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/02/2021] [Accepted: 05/08/2021] [Indexed: 12/15/2022] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the virus that causes coronavirus disease 2019 (COVID-19). The outbreak of this coronavirus was first identified in Wuhan (Hubei, China) in December 2019, and it was declared as pandemic by the World Health Organization (WHO) in March 2020. Today, several vaccines against SARS-CoV-2 have been approved, and some neutralizing monoclonal antibodies are being tested as therapeutic approaches for COVID-19 but, one of the key questions is whether both vaccines and monoclonal antibodies could be effective against infections by new SARS-CoV-2 variants. Nevertheless, there are currently more than 1000 ongoing clinical trials focusing on the use and effectiveness of antiviral drugs as a possible therapeutic treatment. Among the classes of antiviral drugs are included 3CL protein inhibitors, RNA synthesis inhibitors and other small molecule drugs which target the ability of SARS-COV-2 to interact with host cells. Considering the need to find specific treatment to prevent the emergent outbreak, the aim of this review is to explain how some repurposed antiviral drugs, indicated for the treatment of other viral infections, could be potential candidates for the treatment of COVID-19.
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Affiliation(s)
- Luana Vittoria Bauso
- Department of Clinical and Experimental Medicine, University of Messina, 98125 Messina, Italy; (L.V.B.); (C.I.); (G.I.); (G.C.)
| | - Chiara Imbesi
- Department of Clinical and Experimental Medicine, University of Messina, 98125 Messina, Italy; (L.V.B.); (C.I.); (G.I.); (G.C.)
- Laboratori Campisi, Corso Vittorio Emanuele 231, 96012 Avola, Italy
| | - Gasparo Irene
- Department of Clinical and Experimental Medicine, University of Messina, 98125 Messina, Italy; (L.V.B.); (C.I.); (G.I.); (G.C.)
| | - Gabriella Calì
- Department of Clinical and Experimental Medicine, University of Messina, 98125 Messina, Italy; (L.V.B.); (C.I.); (G.I.); (G.C.)
| | - Alessandra Bitto
- Department of Clinical and Experimental Medicine, University of Messina, 98125 Messina, Italy; (L.V.B.); (C.I.); (G.I.); (G.C.)
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Phytochemicals from Selective Plants Have Promising Potential against SARS-CoV-2: Investigation and Corroboration through Molecular Docking, MD Simulations, and Quantum Computations. BIOMED RESEARCH INTERNATIONAL 2020; 2020:6237160. [PMID: 33102585 PMCID: PMC7568149 DOI: 10.1155/2020/6237160] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 08/04/2020] [Accepted: 08/12/2020] [Indexed: 01/07/2023]
Abstract
Coronaviruses have been reported previously due to their association with the severe acute respiratory syndrome (SARS). After SARS, these viruses were known to be causing Middle East respiratory syndrome (MERS) and caused 35% evanescence amid victims pursuing remedial care. Nowadays, beta coronaviruses, members of Coronaviridae, family order Nidovirales, have become subjects of great importance due to their latest pandemic originating from Wuhan, China. The virus named as human-SARS-like coronavirus-2 contains four structural as well as sixteen nonstructural proteins encoded by single-stranded ribonucleic acid of positive polarity. As there is no vaccine available to treat the infection caused by these viruses, there is a dire need for taking necessary steps against this virus. Herein, we have targeted two nonstructural proteins of SARS-CoV-2, namely, methyltransferase (nsp16) and helicase (nsp13), respectively, due to their substantial activity in viral pathogenesis. A total of 2035 compounds were analyzed for their pharmacokinetics and pharmacological properties. The screened 108 compounds were docked against both targeted proteins and were compared with previously reported known compounds. Compounds with high binding affinity were analyzed for their reactivity through DFT analysis, and binding was analyzed using molecular dynamics simulations. Through the analyses performed in this study, it is concluded that EryvarinM, Silydianin, Osajin, and Raddeanine can be considered potential inhibitors for MTase, while TomentodiplaconeB, Osajin, Sesquiterpene Glycoside, Rhamnetin, and Silydianin for helicase after these compounds are validated thoroughly using in vitro and in vivo protocols.
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Chauhan DS, Prasad R, Srivastava R, Jaggi M, Chauhan SC, Yallapu MM. Comprehensive Review on Current Interventions, Diagnostics, and Nanotechnology Perspectives against SARS-CoV-2. Bioconjug Chem 2020; 31:2021-2045. [PMID: 32680422 PMCID: PMC7425040 DOI: 10.1021/acs.bioconjchem.0c00323] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 07/16/2020] [Indexed: 02/06/2023]
Abstract
The coronavirus disease 2019 (COVID-19) has dramatically challenged the healthcare system of almost all countries. The authorities are struggling to minimize the mortality along with ameliorating the economic downturn. Unfortunately, until now, there has been no promising medicine or vaccine available. Herein, we deliver perspectives of nanotechnology for increasing the specificity and sensitivity of current interventional platforms toward the urgent need of quickly deployable solutions. This review summarizes the recent involvement of nanotechnology from the development of a biosensor to fabrication of a multifunctional nanohybrid system for respiratory and deadly viruses, along with the recent interventions and current understanding about severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
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Affiliation(s)
- Deepak S. Chauhan
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Rajendra Prasad
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Rohit Srivastava
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Meena Jaggi
- Department of Immunology and Microbiology, School of Medicine, University of Texas Rio Grande Valley, McAllen, Texas 78504, USA
- South Texas Center of Excellence in Cancer Research, School of Medicine, University of Texas Rio Grande Valley, McAllen, Texas 78504, USA
| | - Subhash C. Chauhan
- Department of Immunology and Microbiology, School of Medicine, University of Texas Rio Grande Valley, McAllen, Texas 78504, USA
- South Texas Center of Excellence in Cancer Research, School of Medicine, University of Texas Rio Grande Valley, McAllen, Texas 78504, USA
| | - Murali M. Yallapu
- Department of Immunology and Microbiology, School of Medicine, University of Texas Rio Grande Valley, McAllen, Texas 78504, USA
- South Texas Center of Excellence in Cancer Research, School of Medicine, University of Texas Rio Grande Valley, McAllen, Texas 78504, USA
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Gu Y, Wang X, Wang Y, Wang Y, Li J, Yu FX. Nelfinavir inhibits human DDI2 and potentiates cytotoxicity of proteasome inhibitors. Cell Signal 2020; 75:109775. [PMID: 32916277 DOI: 10.1016/j.cellsig.2020.109775] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 08/29/2020] [Accepted: 09/06/2020] [Indexed: 01/24/2023]
Abstract
Proteasome inhibitors (PIs) are currently used in the clinic to treat cancers such as multiple myeloma (MM). However, cancer cells often rapidly develop drug resistance towards PIs due to a compensatory mechanism mediated by nuclear factor erythroid 2 like 1 (NFE2L1) and aspartic protease DNA damage inducible 1 homolog 2 (DDI2). Following DDI2-mediated cleavage, NFE2L1 is able to induce transcription of virtually all proteasome subunit genes. Under normal condition, cleaved NFE2L1 is constantly degraded by proteasome, whereas in the presence of PIs, it accumulates and induces proteasome synthesis which in turn promotes the development of drug resistance towards PIs. Here, we report that Nelfinavir (NFV), an HIV protease inhibitor, can inhibit DDI2 activity directly. Inhibition of DDI2 by NFV effectively blocks NFE2L1 proteolysis and potentiates cytotoxicity of PIs in cancer cells. Recent clinical evidence indicated that NFV can effectively delay the refractory period of MM patients treated with PI-based therapy. Our finding hence provides a specific molecular mechanism for combinatorial therapy using NFV and PIs for treating MM and probably additional cancers.
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Affiliation(s)
- Yuan Gu
- Institute of Pediatrics, Children's Hospital of Fudan University, Shanghai Key Laboratory of Medical Epigenetics, Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xin Wang
- Institute of Pediatrics, Children's Hospital of Fudan University, Shanghai Key Laboratory of Medical Epigenetics, Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yu Wang
- Institute of Pediatrics, Children's Hospital of Fudan University, Shanghai Key Laboratory of Medical Epigenetics, Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yebin Wang
- Institute of Pediatrics, Children's Hospital of Fudan University, Shanghai Key Laboratory of Medical Epigenetics, Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jie Li
- Large-scale Protein Preparation System, National Facility for Protein Sciences, Shanghai, China
| | - Fa-Xing Yu
- Institute of Pediatrics, Children's Hospital of Fudan University, Shanghai Key Laboratory of Medical Epigenetics, Institutes of Biomedical Sciences, Shanghai Medical College, Fudan University, Shanghai, China.
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Zhang L, Liu Y. Potential interventions for novel coronavirus in China: A systematic review. J Med Virol 2020; 92:479-490. [PMID: 32052466 PMCID: PMC7166986 DOI: 10.1002/jmv.25707] [Citation(s) in RCA: 700] [Impact Index Per Article: 175.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 02/04/2020] [Indexed: 12/14/2022]
Abstract
An outbreak of a novel coronavirus (COVID‐19 or 2019‐CoV) infection has posed significant threats to international health and the economy. In the absence of treatment for this virus, there is an urgent need to find alternative methods to control the spread of disease. Here, we have conducted an online search for all treatment options related to coronavirus infections as well as some RNA‐virus infection and we have found that general treatments, coronavirus‐specific treatments, and antiviral treatments should be useful in fighting COVID‐19. We suggest that the nutritional status of each infected patient should be evaluated before the administration of general treatments and the current children's RNA‐virus vaccines including influenza vaccine should be immunized for uninfected people and health care workers. In addition, convalescent plasma should be given to COVID‐19 patients if it is available. In conclusion, we suggest that all the potential interventions be implemented to control the emerging COVID‐19 if the infection is uncontrollable.
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Affiliation(s)
- Lei Zhang
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, Liaoning, China
| | - Yunhui Liu
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, Liaoning, China
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Davis MA, Delaney JR, Patel CB, Storgard R, Stupack DG. Nelfinavir is effective against human cervical cancer cells in vivo: a potential treatment modality in resource-limited settings. DRUG DESIGN DEVELOPMENT AND THERAPY 2016; 10:1837-46. [PMID: 27330277 PMCID: PMC4898046 DOI: 10.2147/dddt.s102241] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Objective The standard treatment for cervical cancer in developed countries includes surgery and chemoradiation, with standard of care lagging in developing countries. Even in the former case, treatment frequently yields recalcitrant tumors and women succumb to disease. Here we examine the impact of nelfinavir, an off-patent viral protease inhibitor, which has shown promise as an antineoplastic agent. Methods We evaluated the morphological and proliferative effects of the autophagy-stressing drug nelfinavir in normal and cisplatin-resistant cervical cancer cells. Immunofluorescent validation of autophagy markers was performed and the impact of nelfinavir in an in vivo model of tumor growth was determined. Results Nelfinavir exhibits cytotoxicity against both cisplatin-sensitive and -resistant ME-180 human cervical cancer cells in vitro and in vivo. Immunoblotting and immunofluorescence showed an expression of the autophagy marker LC3-II in response to nelfinavir treatment. Conclusion Nelfinavir, now available as an inexpensive generic orally dosed agent (Nelvir), is cytotoxic against cervical cancer cells. It acts by burdening the autophagy pathway to impair tumor cell survival and a modest induction of apoptosis. While further studies are needed to elucidate the optimal method of application of nelfinavir, it may represent an appealing global option for the treatment of cervical cancer.
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Affiliation(s)
- Mitzie-Ann Davis
- Division of Gynecologic Oncology, Department of Reproductive Medicine, Rebecca and John UCSD Moores Cancer Center, La Jolla, CA, USA
| | - Joe R Delaney
- Division of Gynecologic Oncology, Department of Reproductive Medicine, Rebecca and John UCSD Moores Cancer Center, La Jolla, CA, USA
| | - Chandni B Patel
- Division of Gynecologic Oncology, Department of Reproductive Medicine, Rebecca and John UCSD Moores Cancer Center, La Jolla, CA, USA
| | - Ryan Storgard
- Division of Gynecologic Oncology, Department of Reproductive Medicine, Rebecca and John UCSD Moores Cancer Center, La Jolla, CA, USA
| | - Dwayne G Stupack
- Division of Gynecologic Oncology, Department of Reproductive Medicine, Rebecca and John UCSD Moores Cancer Center, La Jolla, CA, USA
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Hu G, Ma A, Dou X, Zhao L, Wang J. Computational Studies of a Mechanism for Binding and Drug Resistance in the Wild Type and Four Mutations of HIV-1 Protease with a GRL-0519 Inhibitor. Int J Mol Sci 2016; 17:E819. [PMID: 27240358 PMCID: PMC4926353 DOI: 10.3390/ijms17060819] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 05/16/2016] [Accepted: 05/16/2016] [Indexed: 12/22/2022] Open
Abstract
Drug resistance of mutations in HIV-1 protease (PR) is the most severe challenge to the long-term efficacy of HIV-1 PR inhibitor in highly active antiretroviral therapy. To elucidate the molecular mechanism of drug resistance associated with mutations (D30N, I50V, I54M, and V82A) and inhibitor (GRL-0519) complexes, we have performed five molecular dynamics (MD) simulations and calculated the binding free energies using the molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) method. The ranking of calculated binding free energies is in accordance with the experimental data. The free energy spectra of each residue and inhibitor interaction for all complexes show a similar binding model. Analysis based on the MD trajectories and contribution of each residues show that groups R2 and R3 mainly contribute van der Waals energies, while groups R1 and R4 contribute electrostatic interaction by hydrogen bonds. The drug resistance of D30N can be attributed to the decline in binding affinity of residues 28 and 29. The size of Val50 is smaller than Ile50 causes the residue to move, especially in chain A. The stable hydrophobic core, including the side chain of Ile54 in the wild type (WT) complex, became unstable in I54M because the side chain of Met54 is flexible with two alternative conformations. The binding affinity of Ala82 in V82A decreases relative to Val82 in WT. The present study could provide important guidance for the design of a potent new drug resisting the mutation inhibitors.
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Affiliation(s)
- Guodong Hu
- Shandong Provincial Key Laboratory of Biophysics, College of Physics and Electronic Information, Dezhou University, Dezhou 253023, China.
| | - Aijing Ma
- Shandong Provincial Key Laboratory of Biophysics, College of Physics and Electronic Information, Dezhou University, Dezhou 253023, China.
| | - Xianghua Dou
- Shandong Provincial Key Laboratory of Biophysics, College of Physics and Electronic Information, Dezhou University, Dezhou 253023, China.
| | - Liling Zhao
- Shandong Provincial Key Laboratory of Biophysics, College of Physics and Electronic Information, Dezhou University, Dezhou 253023, China.
| | - Jihua Wang
- Shandong Provincial Key Laboratory of Biophysics, College of Physics and Electronic Information, Dezhou University, Dezhou 253023, China.
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Methaneethorn J, Kunyamee P, Jindasri W, Wattanasaovaluk W, Kraiboot A, Lohitnavy M. Pharmacokinetic modeling of simvastatin, nelfinavir and their interaction in humans. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2015; 2014:5715-8. [PMID: 25571293 DOI: 10.1109/embc.2014.6944925] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Simvastatin, a commonly used HMG-CoA reductase inhibitor, is extensively metabolized by CYP3A4. Therefore, co-administration of simvastatin and CYP3A4 inhibitor can affect simvastatin pharmacokinetics. Nelfinavir, a protease inhibitor, and its major metabolite (M8) are known to be potent CYP3A4 inhibitors. When simvastatin and nelfinavir are co-administered, simvastatin pharmacokinetics is significantly altered and may result in an increased risk of rhabdomyolysis. OBJECTIVE To develop a mathematical model describing a drug-drug interaction between simvastatin and nelfinavir in humans. METHODS Eligible pharmacokinetic studies were selected from Pubmed database and concentration time course data were digitally extracted and used for model development. Compartmental pharmacokinetic models for simvastatin and nelfinavir were developed separately. A drug-drug interaction model of simvastatin and nelfinavir was subsequently developed using the prior information. Finally, the final drug-drug interaction modeled was validated against observed simvastatin concentrations. RESULTS Three compartmental pharmacokinetic models were successfully developed. Simvastatin pharmacokinetics was best described by a one compartment model for simvastatin linked to its active form, simvastatin hydroxy acid. Nelfinavir pharmacokinetics could be adequately described by a one compartment parent-metabolite model. Our final drug-drug interaction model predicted an increase in simvastatin exposure which is in line with clinical observations linking the simvastatin-nelfinavir combination to an increased risk of rhabdomyolysis. CONCLUSION Simvastatin-nelfinavir pharmacokinetic interaction can be explained by our final model. This model framework will be useful in further advanced developing other mechanism based drug-drug interaction model used to predict the risk of rhabdomyolysis occurrence in patients prescribed simvastatin and nelfinavir concurrently.
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Boyd MA, Zhang X, Dorr A, Ruxrungtham K, Kolis S, Nieforth K, Kinchelow T, Buss N, Patel IH. Lack of Enzyme-Inducing Effect of Rifampicin on the Pharmacokinetics of Enfuvirtide. J Clin Pharmacol 2013; 43:1382-91. [PMID: 14615475 DOI: 10.1177/0091270003259220] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The primary objective was to determine whether rifampicin influences the pharmacokinetics of enfuvirtide in HIV-1-infected patients. In a single-center, open-label, one-sequence crossover, clinical pharmacology study, 12 HIV-1-infected adults received enfuvirtide (90 mg, twice daily) on days 1 to 3 and days 11 to 13 (morning dose only on days 3 and 13) and rifampicin (600 mg, once daily) from days 4 to 13. Plasma concentrations were measured for enfuvirtide and its metabolite (days 3 and 13) and rifampicin (day 13 only). The ratios of least squares means (LSM) and 90% confidence intervals for enfuvirtide and enfuvirtide metabolite pharmacokinetic parameters (AUC12h, Cmax, Ctrough) were estimated in the presence and absence of rifampicin. Treatments were compared using an analysis of variance for natural log-transformed variables, with factors patient and treatment. Efficacy and safety were also monitored. Steady-state rifampicin had no appreciable effect on any of the pharmacokinetic parameters assessed for either enfuvirtide or its metabolite. The ratio of LSM for AUC12h, Cmax, and Ctrough for enfuvirtide was 97.5%, 103%, and 84.9%, respectively, and 108%, 112%, and 92.9%, for the enfuvirtide metabolite. Rifampicin did not affect the t1/2 of enfuvirtide or its metabolite. There were no unexpected effects of rifampicin on the short-term antiviral effect or safety of the administered antiretroviral treatment. The pharmacokinetics of enfuvirtide are not induced by a 10-day pretreatment with rifampicin.
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Affiliation(s)
- Mark Alastair Boyd
- HIV Netherlands Australia Thailand Research Collaboration (HIV-NAT), the Thai Red Cross AIDS Research Centre, Pathumwan, Bankok, Thailand
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Zhang H, Wang YF, Shen CH, Agniswamy J, Rao KV, Xu CX, Ghosh AK, Harrison RW, Weber IT. Novel P2 tris-tetrahydrofuran group in antiviral compound 1 (GRL-0519) fills the S2 binding pocket of selected mutants of HIV-1 protease. J Med Chem 2013; 56:1074-83. [PMID: 23298236 DOI: 10.1021/jm301519z] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
GRL-0519 (1) is a potent antiviral inhibitor of HIV-1 protease (PR) possessing tris-tetrahydrofuran (tris-THF) at P2. The high resolution X-ray crystal structures of inhibitor 1 in complexes with single substitution mutants PR(R8Q), PR(D30N), PR(I50V), PR(I54M), and PR(V82A) were analyzed in relation to kinetic data. The smaller valine side chain in PR(I50V) eliminated hydrophobic interactions with inhibitor and the other subunit consistent with 60-fold worse inhibition. Asn30 in PR(D30N) showed altered interactions with neighboring residues and 18-fold worse inhibition. Mutations V82A and I54M showed compensating structural changes consistent with 6-7-fold lower inhibition. Gln8 in PR(R8Q) replaced the ionic interactions of wild type Arg8 with hydrogen bond interactions without changing the inhibition significantly. The carbonyl oxygen of Gly48 showed two alternative conformations in all structures likely due to the snug fit of the large tris-THF group in the S2 subsite in agreement with high antiviral efficacy of 1 on resistant virus.
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Affiliation(s)
- Hongmei Zhang
- Department of Biology, Georgia State University, Atlanta, Georgia 30303, USA
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Hoekman JD, Ho RJY. Effects of localized hydrophilic mannitol and hydrophobic nelfinavir administration targeted to olfactory epithelium on brain distribution. AAPS PharmSciTech 2011; 12:534-43. [PMID: 21519984 DOI: 10.1208/s12249-011-9614-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Accepted: 04/04/2011] [Indexed: 11/30/2022] Open
Abstract
Many nasally applied compounds gain access to the brain and the central nervous system (CNS) with varying degree. Direct nose-to-brain access is believed to be achieved through nervous connections which travel from the CNS across the cribriform plate into the olfactory region of the nasal cavity. However, current delivery strategies are not targeted to preferentially deposit drugs to the olfactory at cribriform. Therefore, we have developed a pressurized olfactory delivery (POD) device which consistently and non-invasively deposited a majority of drug to the olfactory region of the nasal cavity in rats. Using both a hydrophobic drug, mannitol (log P = -3.1), and a hydrophobic drug, nelfinavir (log P = 6.0), and POD device, we compared brain and blood levels after nasal deposition primarily on the olfactory region with POD or nose drops which deposited primarily on the respiratory region in rats. POD administration of mannitol in rats provided a 3.6-fold (p < 0.05) increase in cortex-to-blood ratio, compared to respiratory epithelium deposition with nose drop. Administration of nelfinavir provided a 13.6-fold (p < 0.05) advantage in cortex-to-blood ratio with POD administration, compared to nose drops. These results suggest that increasing the fraction of drug deposited on the olfactory region of the nasal cavity will result in increased direct nose-to-brain transport.
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Alfonso Y, Monzote L. HIV Protease Inhibitors: Effect on the Opportunistic Protozoan Parasites. THE OPEN MEDICINAL CHEMISTRY JOURNAL 2011; 5:40-50. [PMID: 21629510 PMCID: PMC3103880 DOI: 10.2174/1874104501105010040] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2010] [Revised: 05/22/2010] [Accepted: 06/28/2010] [Indexed: 11/22/2022]
Abstract
The impact of highly active antiretroviral therapy (HAART) in the natural history of AIDS disease has been allowed to prolong the survival of people with HIV infection, particularly whose with increased HIV viral load. Additionally, the antiretroviral therapy could exert a certain degree of protection against parasitic diseases. A number of studies have been evidenced a decrease in the incidence of opportunistic parasitic infections in the era of HAART. Although these changes have been attributed to the restoration of cell-mediated immunity, induced by either non-nucleoside reverse transcriptase inhibitors or HIV protease inhibitors, in combination with at least two nucleoside reverse transcriptase inhibitors included in HAART, there are evidence that the control of these parasitic infections in HIV-positive persons under HAART, is also induced by the inhibition of the proteases of the parasites. This review focuses on the principal available data related with therapeutic HIV-protease inhibitors and their in vitro and in vivo effects on the opportunistic protozoan parasites.
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Affiliation(s)
- Yenisey Alfonso
- Parasitology Department, Institute of Tropical Medicine “Pedro Kourí”, Cuba
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15
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Braga Neto MB, Aguiar CV, Maciel JG, Oliveira BMC, Sevilleja JE, Oriá RB, Brito GAC, Warren CA, Guerrant RL, Lima AAM. Evaluation of HIV protease and nucleoside reverse transcriptase inhibitors on proliferation, necrosis, apoptosis in intestinal epithelial cells and electrolyte and water transport and epithelial barrier function in mice. BMC Gastroenterol 2010; 10:90. [PMID: 20701796 PMCID: PMC2931456 DOI: 10.1186/1471-230x-10-90] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Accepted: 08/11/2010] [Indexed: 12/29/2022] Open
Abstract
Background Protease inhibitors (PI's) and reverse transcriptase drugs are important components of highly active antiretroviral therapy (HAART) for treating human acquired immunodeficiency syndrome (AIDS). Long-term clinical therapeutic efficacy and treatment compliance of these agents have been limited by undesirable side-effects, such as diarrhea. This study aims to investigate the effects of selected antiretroviral agents on intestinal histopathology and function in vivo and on cell proliferation and death in vitro. Methods Selected antiretroviral drugs were given orally over 7 days, to Swiss mice, as follows: 100 mg/kg of nelfinavir (NFV), indinavir (IDV), didanosine (DDI) or 50 mg/kg of zidovudine (AZT). Intestinal permeability measured by lactulose and mannitol assays; net water and electrolyte transport, in perfused intestinal segments; and small intestinal morphology and cell apoptosis were assessed in treated and control mice. In vitro cell proliferation was evaluated using the WST-1 reagent and apoptosis and necrosis by flow cytometry analysis. Results NFV, IDV, AZT and DDI caused significant reductions in duodenal and in jejunal villus length (p < 0.05). IDV and AZT increased crypt depth in the duodenum and AZT increased crypt depth in the jejunum. NFV, AZT and DDI significantly decreased ileal crypt depth. All selected antiretroviral drugs significantly increased net water secretion and electrolyte secretion, except for DDI, which did not alter water or chloride secretion. Additionally, only NFV significantly increased mannitol and lactulose absorption. NFV and IDV caused a significant reduction in cell proliferation in vitro at both 24 h and 48 h. DDI and AZT did not alter cell proliferation. There was a significant increase in apoptosis rates in IEC-6 cells after 24 h with 70 ug/mL of NFV (control: 4.7% vs NFV: 22%) while IDV, AZT and DDI did not show any significant changes in apoptosis compared to the control group. In jejunal sections, IDV and NFV significantly increased the number of TUNEL positive cells. Conclusion The PI's, NFV and IDV, increased cell apoptosis in vivo, water and electrolyte secretion and intestinal permeability and decreased villus length and cell proliferation. NFV was the only drug tested that increased cell apoptosis in vitro. The nucleoside reverse transcriptase inhibitors, AZT and DDI, did not affect cell apoptosis or proliferation. These findings may partly explain the intestinal side-effects associated with PI's.
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Affiliation(s)
- Manuel B Braga Neto
- Institute of Biomedicine and Clinical Research Unit-University Hospital, Federal University of Ceará, Fortaleza, Brazil
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Modulation of endocrine and transport functions in human trophoblasts by saquinavir and nelfinavir. Eur J Obstet Gynecol Reprod Biol 2010; 152:55-9. [PMID: 20591557 DOI: 10.1016/j.ejogrb.2010.05.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Revised: 03/19/2010] [Accepted: 05/24/2010] [Indexed: 02/03/2023]
Abstract
OBJECTIVES The distribution of drugs to the maternal-fetal interface is influenced by the expression of various efflux transporters. Among these transporters, P-glycoprotein (P-gp) is responsible for the efflux of a great number of drugs such as protease inhibitors of the human immunodeficiency virus, thus reducing the chemical exposure of the fetus. STUDY DESIGN The effects of saquinavir and nelfinavir were evaluated on human trophoblast functions and integrity by investigating their effect on human chorionic gonadotropin (hCG) secretion and on P-gp expression and functionality. RESULTS Nelfinavir significantly reduced hCG secretion by 30% after a 48-h treatment but it had no effect on syncytia formation. Saquinavir had no effect on hCG secretion but significantly increased both expression (to a 2-fold extent) and functionality (by 17.9%) of P-gp, whereas nelfinavir only increased functionality (by 23.1%) with a dissociation of P-gp from caveolin-1. CONCLUSION These results suggest that the effects of saquinavir and nelfinavir differ on trophoblast functions.
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Chen J, Zhang S, Liu X, Zhang Q. Insights into drug resistance of mutations D30N and I50V to HIV-1 protease inhibitor TMC-114: free energy calculation and molecular dynamic simulation. J Mol Model 2009; 16:459-68. [PMID: 19629548 DOI: 10.1007/s00894-009-0553-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2009] [Accepted: 06/11/2009] [Indexed: 12/01/2022]
Abstract
The single mutations D30N and I50V are considered as the key residue mutations of the HIV-1 protease drug resistance to inhibitors in clinical use. In this work, molecular dynamics (MD) simulations combined with the molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) method have been performed to investigate the drug-resistant mechanisms of D30N and I50V to an inhibitor TMC-114. The analyses of absolute binding free energies using the separate trajectory approach suggests that the decrease in the van der Waals energy and electrostatic energy in the gas phase results in the drug resistance of D30N to TMC-114, while for I50V, the decrease in the electrostatic energy mainly drive its drug resistance to TMC-114. Detailed binding free energies between TMC-114 and individual protein residues are computed by using a per-residue basis decomposition method, which provides insights into the inhibitor-protein binding mechanism and also explains the drug-resistant mechanisms of mutations D30N and I50V to TMC-114. The study shows that the loss of the hydrogen bond between TMC-114 and the side chain of Asn30' is the main driving force of the resistance of D30N to TMC-114, and in the case of I50V, the increase in the polar solvation energies between TMC-114 and two residues Val50' and Asp30' definitively drives the resistance of I50V to TMC-114. We expect that this work can provide some helpful insights into the nature of mutational effect and aid the future design of better inhibitors.
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Affiliation(s)
- Jianzhong Chen
- College of Physics and Electronics, Shandong Normal University, Jinan, 250014, China
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18
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Wang YF, Tie Y, Boross PI, Tozser J, Ghosh AK, Harrison RW, Weber IT. Potent new antiviral compound shows similar inhibition and structural interactions with drug resistant mutants and wild type HIV-1 protease. J Med Chem 2007; 50:4509-15. [PMID: 17696515 PMCID: PMC2751596 DOI: 10.1021/jm070482q] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The potent new antiviral inhibitor GRL-98065 (1) of HIV-1 protease (PR) has been studied with PR variants containing the single mutations D30N, I50V, V82A, and I84V that provide resistance to the major clinical inhibitors. Compound 1 had inhibition constants of 17-fold, 8-fold, 3-fold, and 3-fold, respectively, for PR(D30N), PR(I50V), PR(V82A), and PR(I84V) relative to wild type PR. The chemically related darunavir had similar relative inhibition, except for PR(D30N), where inhibitor 1 was approximately 3-fold less potent. The high resolution (1.11-1.60 Angstrom) crystal structures of PR mutant complexes with inhibitor 1 showed small changes relative to the wild type enzyme. PR(D30N) and PR(V82A) showed compensating interactions with inhibitor 1 relative to those of PR, while reduced hydrophobic contacts were observed with PR(I50V) and PR(I84V). Importantly, inhibitor 1 complexes showed fewer changes relative to wild type enzyme than reported for darunavir complexes. Therefore, inhibitor 1 is a valuable addition to the antiviral inhibitors with high potency against resistant strains of HIV.
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Affiliation(s)
- Yuan-Fang Wang
- Department of Biology, Molecular Basis of Disease, Georgia State University, Atlanta, Georgia 30303, USA
| | - Yunfeng Tie
- Department of Biology, Molecular Basis of Disease, Georgia State University, Atlanta, Georgia 30303, USA
| | - Peter I. Boross
- Department of Biology, Molecular Basis of Disease, Georgia State University, Atlanta, Georgia 30303, USA
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Jozsef Tozser
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Arun K. Ghosh
- Department of Chemistry and Medicinal Chemistry, Purdue University, West Lafayette, IN 47907, USA
| | - Robert W. Harrison
- Department of Computer Science, Georgia State University, Atlanta, Georgia 30303, USA
| | - Irene T. Weber
- Department of Biology, Molecular Basis of Disease, Georgia State University, Atlanta, Georgia 30303, USA
- Department of Chemistry, Molecular Basis of Disease, Georgia State University, Atlanta, Georgia 30303, USA
- Department of Biology, Georgia State University, 402 Kell Hall, 24 Peachtree Center Ave., Atlanta GA 30303, Phone: 404-413-5411, Fax: 404-413-5301,
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Torne SJ, Torne JS, Vavia PR, Singh SK, Kishore N. Cyclodextrin based drug delivery system of protease inhibitor—nelfinavir mesylate. J INCL PHENOM MACRO 2007. [DOI: 10.1007/s10847-006-9262-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Ferguson NM, Donnelly CA, Hooper J, Ghani AC, Fraser C, Bartley LM, Rode RA, Vernazza P, Lapins D, Mayer SL, Anderson RM. Adherence to antiretroviral therapy and its impact on clinical outcome in HIV-infected patients. J R Soc Interface 2006; 2:349-63. [PMID: 16849193 PMCID: PMC1578278 DOI: 10.1098/rsif.2005.0037] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We analyse data on patient adherence to prescribed regimens and surrogate markers of clinical outcome for 168 human immunodeficiency virus infected patients treated with antiretroviral therapy. Data on patient adherence consisted of dose-timing measurements collected for an average of 12 months per patient via electronic monitoring of bottle opening events. We first discuss how such data can be presented to highlight suboptimal adherence patterns and between-patient differences, before introducing two novel methods by which such data can be statistically modelled. Correlations between adherence and subsequent measures of viral load and CD4+T-cell counts are then evaluated. We show that summary measures of short-term adherence, which incorporate pharmacokinetic and pharmacodynamic data on the monitored regimen, predict suboptimal trends in viral load and CD4+T-cell counts better than measures based on adherence data alone.
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Affiliation(s)
- N M Ferguson
- Department of Infectious Disease Epidemiology, Faculty of Medicine, Imperial College London, Norfolk Place, London W2 1PG, UK.
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Kohli-Pamnani A, Huynh P, Lobo F. Amprenavir-induced maculopapular exanthem followed by desensitization in a patient with late-stage human immunodeficiency virus. Ann Allergy Asthma Immunol 2006; 96:620-3. [PMID: 16680935 DOI: 10.1016/s1081-1206(10)63559-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND Amprenavir, a human immunodeficiency virus type 1 (HIV-1) protease inhibitor, is approved for the treatment of HIV infection in combination with other antiretroviral agents in treatment-naive and experienced patients. Amprenavir is generally well tolerated. However, cutaneous hypersensitivity reactions to amprenavir occur in up to 28% of patients, with treatment discontinuation required in 3% of cases. OBJECTIVE To report successful desensitization to amprenavir after the occurrence of a maculopapular exanthem in an HIV-infected patient with late-stage disease and limited antiretroviral treatment options. METHODS Incremental doses of 0.025, 0.1, 0.25, 1, 2.5, 7.5, 25, 50, 100, 300, 600, and 1,200 mg of amprenavir oral solution were administered via percutaneous endoscopic gastrostomy tube at 20- to 30-minute intervals. RESULTS The patient successfully tolerated amprenavir desensitization and has continued therapy without recurrence of rash at 19 months of follow-up. CONCLUSION Desensitization may permit the continued use of amprenavir in HIV-positive patients with a history of amprenavir-induced maculopapular eruptions who have limited alternate treatment options.
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Samuel R, Bettiker R, Suh B. Antiretroviral therapy 2006: Pharmacology, applications, and special situations. Arch Pharm Res 2006; 29:431-58. [PMID: 16833010 DOI: 10.1007/bf02969415] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
As we approach the completion of the first 25 years of the human immunodeficiency virus (HIV) epidemic, there have been dramatic improvements in the care of patients with HIV infection. These have prolonged life and decreased morbidity. There are twenty currently available antiretrovirals approved in the United States for the treatment of this infection. The medications, including their pharmacokinetic properties, side effects, and dosing are reviewed. In addition, the current approach to the use of these medicines is discussed. We have included a section addressing common comorbid conditions including hepatitis B and C along with tuberculosis.
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Affiliation(s)
- Rafik Samuel
- Section of Infectious Diseases, Temple University School of Medicine, Philadelphia, PA 19140, USA.
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Jing Q, Shen Y, Tang Y, Ren F, Yu X, Hou Z. Determination of nelfinavir mesylate as bulk drug and in pharmaceutical dosage form by stability indicating HPLC. J Pharm Biomed Anal 2006; 41:1065-9. [PMID: 16545536 DOI: 10.1016/j.jpba.2006.02.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2005] [Revised: 01/30/2006] [Accepted: 02/01/2006] [Indexed: 10/24/2022]
Abstract
A isocratic, selective, accurate and stability indicating HPLC method of analysis of nelfinavir mesylate both as a bulk drug and in formulations was developed and validated. A CN chromatographic column (250 mmx4.6 mm, 5 microm) was used for the separation at 40 degrees C. The mobile phase consisted of a mixture of acetonitrile (MeCN) and 25 mM monobasic ammonium phosphate (containing 25 mM triethylamine, pH 3.4 with phosphate acid) (40:60, v/v) was delivered at a flow rate of 1.0 ml/min with detection at 210 nm. The developed method was validated in terms of selectivity, linearity, limit of quantitation, precision, accuracy and solution stability. As the proposed LC method achieved satisfactory resolution between nelfinavir mesylate, its degradation products, intermediate product possibly present in nelfinavir drug substance and other impurities in the end product before refining in the final step of synthetic process, it can be employed as a stability indicating one, used for the synthetic process control and determination of nelfinavir mesylate in pharmaceutical preparations.
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Affiliation(s)
- Qiufang Jing
- Department of Pharmaceutical Engineering, School of Chemistry and Pharmaceutics, East China University of Science and Technology, Shanghai 200237, China
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24
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Kovalevsky AY, Tie Y, Liu F, Boross PI, Wang YF, Leshchenko S, Ghosh AK, Harrison RW, Weber IT. Effectiveness of nonpeptide clinical inhibitor TMC-114 on HIV-1 protease with highly drug resistant mutations D30N, I50V, and L90M. J Med Chem 2006; 49:1379-87. [PMID: 16480273 PMCID: PMC3015180 DOI: 10.1021/jm050943c] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The potent new antiviral inhibitor TMC-114 (UIC-94017) of HIV-1 protease (PR) has been studied with three PR variants containing single mutations D30N, I50V, and L90M, which provide resistance to the major clinical inhibitors. The inhibition constants (K(i)) of TMC-114 for mutants PR(D30N), PR(I50V), and PR(L90M) were 30-, 9-, and 0.14-fold, respectively, relative to wild-type PR. The molecular basis for the inhibition was analyzed using high-resolution (1.22-1.45 A) crystal structures of PR mutant complexes with TMC-114. In PR(D30N), the inhibitor has a water-mediated interaction with the side chain of Asn30 rather than the direct interaction observed in PR, which is consistent with the relative inhibition. Similarly, in PR(I50V) the inhibitor loses favorable hydrophobic interactions with the side chain of Val50. TMC-114 has additional van der Waals contacts in PR(L90M) structure compared to the PR structure, leading to a tighter binding of the inhibitor. The observed changes in PR structure and activity are discussed in relation to the potential for development of resistant mutants on exposure to TMC-114.
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Affiliation(s)
- Andrey Yu. Kovalevsky
- Department of Biology, Molecular Basis of Disease, Georgia State University, Atlanta, Georgia 30303, USA
| | - Yunfeng Tie
- Department of Chemistry, Molecular Basis of Disease, Georgia State University, Atlanta, Georgia 30303, USA
| | - Fengling Liu
- Department of Biology, Molecular Basis of Disease, Georgia State University, Atlanta, Georgia 30303, USA
| | - Peter I. Boross
- Department of Biology, Molecular Basis of Disease, Georgia State University, Atlanta, Georgia 30303, USA
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Yuan-Fang Wang
- Department of Biology, Molecular Basis of Disease, Georgia State University, Atlanta, Georgia 30303, USA
| | - Sofiya Leshchenko
- Department of Chemistry and Medicinal Chemistry, Purdue University, West Lafayette, IN 47907, USA
| | - Arun K. Ghosh
- Department of Chemistry and Medicinal Chemistry, Purdue University, West Lafayette, IN 47907, USA
| | - Robert W. Harrison
- Department of Computer Science, Georgia State University, Atlanta, Georgia 30303, USA
| | - Irene T. Weber
- Department of Biology, Molecular Basis of Disease, Georgia State University, Atlanta, Georgia 30303, USA
- Department of Chemistry, Molecular Basis of Disease, Georgia State University, Atlanta, Georgia 30303, USA
- *Department of Biology, Georgia State University, 402 Kell Hall, 24 Peachtree Center Ave., Atlanta GA 30303, Phone: 404-651-0098, Fax: 404-651-2509, E-mail:
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Perez G, MacArthur RD, Walmsley S, Baxter JA, Mullin C, Neaton JD. A randomized clinical trial comparing nelfinavir and ritonavir in patients with advanced HIV disease (CPCRA 042/CTN 102). HIV CLINICAL TRIALS 2004; 5:7-18. [PMID: 15002082 DOI: 10.1310/n11f-nk93-mumr-a1vv] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To compare the long-term clinical efficacy and toxicity of initial strategies of nelfinavir (NFV) or ritonavir (RTV) in patients with CD4+ cells below 200/mm3. METHOD This was an open-label randomized multicenter trial (CPCRA, CTN). Patients were naïve to protease inhibitor use except for hard gel saquinavir. Patients who were intolerant to their assigned therapy were allowed to switch arms (later RTV-intolerant patients could switch to indinavir). The primary objective was to compare the regimens for AIDS-defining conditions and death (AIDS/death) using intent-to-treat analysis. Hazard ratios (HR) for NFV and RTV were estimated using Cox's proportional hazards models. Kaplan-Meier life table summaries were also used to compare the two groups. RESULTS There were 775 patients who were randomized beginning in January 1997 and followed through December 2001. At entry, mean CD4+ cell count was 58 cells/mm3 and HIV RNA level averaged 4.9 log copies/mL. After a median follow-up of 52 months, rates of AIDS/death were 12.7 and 11.0 per 100 person years for the NFV and RTV groups, respectively (HR=1.16; 95% CI, 0.92-1.46; p=.21). Discontinuations occurred earlier in the RTV group (p=.0001). CONCLUSION There are moderate differences in efficacy and large differences in tolerability between a strategy of initial NFV or RTV in patients with advanced disease. Finding the right balance between potency and tolerability remains a challenge.
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Affiliation(s)
- George Perez
- North Jersey Community Research Initiative, Newark, NJ 07103, USA.
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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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Floren LC, Wiznia A, Hayashi S, Jayewardene A, Stanley K, Johnson G, Nachman S, Krogstad P, Aweeka FT. Nelfinavir pharmacokinetics in stable human immunodeficiency virus-positive children: Pediatric AIDS Clinical Trials Group Protocol 377. Pediatrics 2003; 112:e220-7. [PMID: 12949316 DOI: 10.1542/peds.112.3.e220] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE Pharmacokinetic data obtained from children who have human immunodeficiency virus (HIV) infection are essential for the safe and effective use of antiretroviral agents in pediatric populations. The objective of this study was to assess the impact of body weight on the pharmacokinetic disposition of nelfinavir (NFV) in the absence and presence of nevirapine (NVP) and compare the pharmacokinetic profiles of twice-daily (BID) and three-times-daily (TID) NFV regimens. METHODS This was an intensive pharmacokinetic substudy nested in a phase II, multicenter, randomized, open-label trial. Forty-five HIV-infected children receiving NFV 30 mg/kg TID and 6 HIV-infected children receiving NFV 55 mg/kg BID were enrolled in this study and assigned to 1 of 4 stavudine-containing regimens, 3 containing NFV and 2 containing NVP. Area under the plasma concentration-time curves from 0 to 8 hours (AUC(0-8 hours)) and from 0 to 12 hours (AUC(0-12 hours)) for the TID and BID regimens, respectively, were determined. For comparative purposes, the AUC(0-24 hours) was also calculated for each regimen. RESULTS NFV exposure in the absence of NVP was decreased in children who were <25 kg compared with those who were >25 kg (a 2.6-fold difference in median AUC(0-8 hours)). NFV pharmacokinetics in the presence of NVP did not differ between the <25 kg and >25 kg groups. The AUC(0-24 hours) for children who were <30 kg and on NFV BID was comparable to the AUC(0-24 hours) for children who were >25 kg and on NFV TID but was 2.7-fold greater than AUC(0-24 hours) for children who were <25 kg and on NFV TID. CONCLUSIONS NFV in the absence of NVP resulted in less than half the drug exposure in children who were <25 kg compared with children who were >25 kg. NFV dosed at 55 mg/kg BID in children who are <30 kg provides comparable exposure to that measured in children who are >25 kg and receiving NFV 30 mg/kg TID.
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Affiliation(s)
- Leslie Carstensen Floren
- Drug Research Unit, Department of Clinical Pharmacy, University of California, San Francisco, California, USA
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29
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Lemberg DA, Palasanthiran P, Goode M, Ziegler JB. Tolerabilities of antiretrovirals in paediatric HIV infection. Drug Saf 2003; 25:973-91. [PMID: 12408730 DOI: 10.2165/00002018-200225140-00001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Data on the efficacy and tolerability of antiretrovirals in children are limited as, in contrast to adult studies, large paediatric cohort studies are lacking. Thus, data pertaining to adults are often extrapolated to children despite the acknowledgement that children are not little adults. This review summarises information gathered from existing reports and focuses on the tolerabilities of antiretrovirals in children infected with HIV-1. The efficacy of antiretrovirals is not included in the scope of the discussion. Taste of antiretrovirals should be an important factor when considering the tolerability of antiretrovirals in children. However, antiretroviral options are often limited in young children as only some of the antiretrovirals are available as paediatric formulations. All antiretrovirals have been associated with toxicities in children, but in general, they are relatively well tolerated. The gastrointestinal system including hepatic system is most prone to being affected by these drugs. Skin rashes and hypersensitivity reactions are also associated with antiretroviral use, particularly with the non-nucleoside reverse transcriptase inhibitors. Mitochondrial toxicities that lead to impairment of liver function, pancreatic function and lactic acidosis are associated with most of the nucleoside analogues. Haematological toxicity is often a dose limiting adverse effect especially of the nucleoside analogues, in particular zidovudine. The protease inhibitors are associated with gastrointestinal intolerance (diarrhoea) and metabolic derangements that can lead to hypercholesterolaemia and hypertriglyceridaemia, which in turn and can lead to changes in body habitus. The renal system is also affected by several drugs, the most important of which is indinavir, which has been associated with renal stones and damage to the renal tubules. Fortunately, with lower incidence of major toxicity and with the range of drugs now available for paediatric use, toxicities are usually not a barrier to effect antiretroviral therapy in children.
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Affiliation(s)
- Daniel Avi Lemberg
- Department of Immunology and Infectious Diseases, Sydney Children's Hospital, Randwick, New South Wales, Australia
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Abstract
In comparison with HIV infection in adults, higher HIV RNA levels in children with perinatal HIV infection, differences in the natural history of HIV disease progression, and the presence of a relatively immature immune system contribute to the more complex and problematic nature of pediatric antiretroviral therapy. Current US treatment guidelines for pediatric HIV infection advocate aggressive therapy with potent combination antiretroviral regimens, to achieve profound and durable suppression of viral replication and preservation of immune function. The combination of a protease inhibitor (PI) and dual nucleoside reverse transcriptase inhibitors (NRTIs) is the most commonly recommended form of highly active antiretroviral treatment (HAART). However, use of PI therapy in pediatrics has been constrained by the lack of suitable drug formulations, a paucity of pharmacokinetic and safety data, and drug intolerance. Pharmacokinetic studies of PIs demonstrate frequent differences between children and adults, and greater variability among children, which has led to subtherapeutic dosage regimens and the development of viral resistance. The optimal dosage of many PIs in younger children is not yet known. A therapeutically important drug interaction associated with PIs is that occurring between the various PIs themselves, which allows lower doses of PI at less frequent intervals. Dual PI regimens will probably become more common, as they permit a simpler antiretroviral regimen, lower pill/medication burden, fewer adverse effects and improved adherence. Poor adherence to antiretroviral therapy remains the greatest barrier to overall success in the treatment of HIV-infected children. The key to improving adherence in HIV-infected children is to find treatment regimens that are better suited to their normal life. With improvements in existing PIs and the development of newer ones, simplification of current antiretroviral therapy to once-daily regimens without loss of potency should be achievable. PI-containing HAART has transformed HIV infection into a chronic illness, and HIV-infected children now live longer.
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Affiliation(s)
- Patrick J Gavin
- Division of Infectious Diseases, Children's Memorial Hospital and the Departments of Pediatrics, Northwestern University Medical School, Chicago, Illinois 60614-3394, USA
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Jensen-Fangel S, Justesen US, Black FT, Pedersen C, Obel N. The use of calcium carbonate in nelfinavir-associated diarrhoea in HIV-1-infected patients. HIV Med 2003; 4:48-52. [PMID: 12534959 DOI: 10.1046/j.1468-1293.2003.00135.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVES To evaluate the efficacy of oral calcium supplements in HIV-infected patients with nelfinavir (NFV)-associated diarrhoea, and to investigate the influence on the pharmacokinetics of nelfinavir and the active metabolite M8. METHODS An open-label prospective trial with enrolment of 15 patients with NFV-associated diarrhoea. Study subjects received either calcium carbonate or calcium gluconate/calcium carbonate in addition to highly active antiretroviral therapy (HAART), and were randomized to (i) calcium supplements for 14 days followed by 14 without calcium supplements, or (ii) 14 days without calcium supplements followed by calcium supplements for 14 days. Clinical endpoint was the severity of diarrhoea, graded and summarized for the specific 14 day-period. In the pharmacokinetic evaluation concentrations of NFV and M8 were measured before morning dosing, and 3 h after dosing. RESULTS Nine patients were treated with calcium carbonate, and six with calcium gluconate/calcium carbonate. In the paired analysis, neither of the groups had a significant improvement in diarrhoea score when treated with calcium supplements (P = 0.34 and 0.46, respectively). We found no significant differences in the concentrations of NFV and M8 between the calcium and control periods. CONCLUSIONS Oral calcium supplements did not significantly improve nelfinavir-associated diarrhoea. In the pharmacokinetic analysis calcium supplements did not induce major alterations in plasma concentrations of NFV and M8.
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Affiliation(s)
- S Jensen-Fangel
- Department of Infectious Diseases, Aarhus University Hospital, Aarhus, Denmark.
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Lu JF, Blaschke TF, Flexner C, Rosenkranz SL, Sheiner LB. Model-based analysis of the pharmacokinetic interactions between ritonavir, nelfinavir, and saquinavir after simultaneous and staggered oral administration. Drug Metab Dispos 2002; 30:1455-61. [PMID: 12433819 DOI: 10.1124/dmd.30.12.1455] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Eighteen healthy human immunodeficiency virus-negative subjects participated in an open-label, six-period, incomplete Latin-square crossover pharmacokinetic study. Each subject received two of the three possible pair-wise combinations of single-dose oral ritonavir (R) (400 mg), nelfinavir (N) (750 mg), and saquinavir (S) (800 mg), each pair on three occasions (simultaneous or staggered administration), each occasion at least 2 days after the last. A model-based analysis reveals the following major drug interactions under the conditions of this study: 1). R given simultaneously with S decreases S hepatic intrinsic clearance almost 50-fold relative to that predicted for S given alone and increases its gut bioavailability 90% (but decreases its rate of absorption 40%) relative to when N is given simultaneously; 2). N given simultaneously with S decreases S hepatic intrinsic clearance 10-fold relative to that predicted for S given alone; and 3) R inhibits S hepatic intrinsic clearance even after R plasma levels have become undetectable (>48 h after dosing), implying that R, when used as a pharmacokinetic enhancer, can be dosed less frequently than might be predicted from the duration of detectable systemic concentrations.
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Affiliation(s)
- Jian-Feng Lu
- Department of Biopharmaceutical Sciences, University of California San Francisco, San Francisco, California 94143-0626, USA
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Blumenzweig I, Baraz L, Friedler A, Danielson UH, Gilon C, Steinitz M, Kotler M. HIV-1 Vif-derived peptide inhibits drug-resistant HIV proteases. Biochem Biophys Res Commun 2002; 292:832-40. [PMID: 11944889 DOI: 10.1006/bbrc.2002.6732] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Vif, one of the six accessory genes expressed by HIV-1, is essential for the productive infection of natural target cells. Previously we suggested that Vif acts as a regulator of the viral protease (PR): It prevents the autoprocessing of Gag and Gag-Pol precursors until virus assembly, and it may control the PR activity in the preintegration complex at the early stage of infection. It was demonstrated before that Vif, and specifically the 98 amino acid stretch residing at the N'-terminal part of Vif (N'-Vif), inhibits both the autoprocessing of truncated Gag-Pol polyproteins in bacterial cells and the hydrolysis of synthetic peptides by PR in cell-free systems. Linear synthetic peptides derived from N'-Vif specifically inhibit and bind HIV-1 PR in vitro, and arrest virus production in tissue culture. Peptide mapping of N'-Vif revealed that Vif88-98 is the most potent PR inhibitor. Here we report that this peptide inhibits both HIV-1 and HIV-2, but not ASLV proteases in vitro. Vif88-98 retains its inhibitory effect against drug-resistant HIV-1 PR variants, isolated from patients undergoing long-term treatment with anti-PR drugs. Variants of HIV protease bearing the mutation G48V are resistant to inhibition by this Vif-derived peptide, as shown by in vitro assays. In agreement with the in vitro experiments, Vif88-98 has no effect on the production of infectious particles in cells infected with a G48V mutated virus.
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Affiliation(s)
- Immanuel Blumenzweig
- Department of Pathology, Hebrew University-Hadassah Medical School, Jerusalem, 91120, Israel
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Back D, Gatti G, Fletcher C, Garaffo R, Haubrich R, Hoetelmans R, Kurowski M, Luber A, Merry C, Perno CF. Therapeutic drug monitoring in HIV infection: current status and future directions. AIDS 2002; 16 Suppl 1:S5-37. [PMID: 12035820 DOI: 10.1097/00002030-200203001-00002] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Highly active antiretroviral therapy (HAART) can suppress viral replication and prolong patient life substantially. However, HAART can fail for a number of reasons, including incomplete adherence, pharmacokinetic factors and the emergence of resistance. Because the number of possible antiretroviral combinations is limited, the use of existing treatment options must be optimized. Whether the application of therapeutic drug monitoring (TDM) in routine clinical practice may help with this purpose remains a subject of debate. However, TDM has been introduced in some centres despite the lack of guidelines for optimal use of this test. OBJECTIVE In October 2000, a panel of experts met in Perugia, Italy, to discuss the key issues surrounding the introduction of TDM into routine clinical practice. The purpose of the meeting was to achieve a consensus among panel members on the following issues: (i) validity of data suggesting the utility of TDM in HAART; (ii) patient categories and clinical settings in which TDM may be of most benefit; (iii) target levels of antiretroviral agents; (iv) influence of covariables on target levels of drugs; (v) blood sampling and dosage adjustment strategies; and (vi) future research steps needed to elucidate issues regarding the applicability of TDM in clinical practice. OUTCOME This report, which has been updated to include data published or presented at conferences up to the end of August 2001, summarizes the data presented and issues discussed at the meeting. This article will guide the reader through the data and discussions that have allowed the panel to formulate a series of position statements regarding the current status and future applications of TDM in antiretroviral therapy. These statements have been formulated to provide suggestions for the design of future TDM clinical trials, as well as to provide useful points of reflection for centres in which TDM is already in use.
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Affiliation(s)
- David Back
- Pharmacology Research Laboratories, University of Liverpool, UK.
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Skowron G, Street JC, Obee EM. Baseline CD4(+) cell count, not viral load, correlates with virologic suppression induced by potent antiretroviral therapy. J Acquir Immune Defic Syndr 2001; 28:313-9. [PMID: 11707666 DOI: 10.1097/00126334-200112010-00002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To investigate the relationship between viral load suppression and baseline viral load as well as that between viral load suppression and baseline CD4(+) cell count. DESIGN Meta-analysis of published and presented studies. METHODS Trials of two nucleoside analogs plus nevirapine, indinavir, nelfinavir, or efavirenz as therapy for antiretroviral treatment-naive patients with HIV infection or AIDS who were followed-up for at least 6 months were included in the meta-analysis. The proportion of patients with viral loads of <200-500 copies/ml at 6 and 12 months (total number of patients, 1619 and 761, respectively) was regressed to the mean or median baseline viral load and CD4(+) cell count. RESULTS Thirty-six treatment arms from 30 studies were identified. Multivariate regression demonstrated a significant correlation between baseline CD4(+) cell count and virologic suppression at 6 and 12 months ( t = 2.85, p =.008; and t = 3.08, p =.010, respectively) but not between baseline viral load and virologic suppression ( t = 0.92, p =.365; and t = 1.31, p =.215, respectively). The same pattern was seen in a subanalysis of trials of nevirapine-containing therapy (CD4(+) cell count: t = 2.89, p =.014 at 6 months; viral load suppression: t = 0.84, p =.415). CONCLUSIONS Baseline CD4(+) cell count was a better predictor of virologic suppression induced by triple combination therapy than was baseline viral load.
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Affiliation(s)
- G Skowron
- Roger Williams Medical Center/Boston University, Providence, Rhode Island 02908, USA.
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Phenix BN, Lum JJ, Nie Z, Sanchez-Dardon J, Badley AD. Antiapoptotic mechanism of HIV protease inhibitors: preventing mitochondrial transmembrane potential loss. Blood 2001; 98:1078-85. [PMID: 11493454 DOI: 10.1182/blood.v98.4.1078] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Treatment of cells with the HIV drugs ritonavir, saquinavir, or nelfinavir (Nfv) inhibits apoptosis induced by a variety of stimuli. Because these drugs are protease inhibitors, they have been postulated to inhibit apoptosis by blocking caspase activity. This study shows that Nfv has no effect on caspase activity or on the transcription or synthesis of a variety of apoptosis regulatory molecules. Instead, Nfv inhibits mitochondrial transmembrane potential loss (Delta psi(m)) and the subsequent release of apoptotic mediators. Consequently, the antiapoptotic effects of Nfv are restricted to apoptotic pathways that involve Delta psi(m). (Blood. 2001;98:1078-1085)
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Affiliation(s)
- B N Phenix
- Ottawa Hospital Research Institute, University of Ottawa, ON, Canada
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Baede-van Dijk PA, Hugen PW, Verweij-van Wissen CP, Koopmans PP, Burger DM, Hekster YA. Analysis of variation in plasma concentrations of nelfinavir and its active metabolite M8 in HIV-positive patients. AIDS 2001; 15:991-8. [PMID: 11399981 DOI: 10.1097/00002030-200105250-00007] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To characterize sources of variation in plasma concentrations of nelfinavir and its active metabolite M8 and to evaluate the use of therapeutic drug monitoring for nelfinavir treatment. METHODS Plasma samples and patient's characteristics were obtained from outpatient clinic. Differences between groups of patients were studied by comparing the observed plasma concentrations with the corresponding concentration on a pharmacokinetic population curve based on median plasma levels. RESULTS Plasma samples (618) were available from 355 patients taking 1250 mg nelfinavir twice daily. The median ratio between M8 and nelfinavir concentrations was 0.29. This ratio appeared to be independent of the time after ingestion. Statistically significantly lower M8 concentrations were found in Black and Asian patients, or when comedication with CYP3A4 inducers was used. Coadministration of CYP2C19 inhibitors, such as omeprazole, decreased the median M8/nelfinavir ratio. Nevertheless, nelfinavir concentrations and summed concentrations of nelfinavir and M8 were only marginally affected in these patients. Diarrhoea was identified as a cause for lower nelfinavir concentrations, without changing the M8/nelfinavir ratio. In a number of patients with suspected therapy failure or intoxication, abnormal nelfinavir plasma concentrations were found. Dose adjustments based on nelfinavir plasma levels were helpful in a number of patients. CONCLUSION This study shows that the total concentration of nelfinavir and M8 together is not significantly influenced when variation in M8 levels occurs. Consequently, measuring M8 concentrations in addition to nelfinavir concentrations is not required for the purpose of therapeutic drug monitoring for this drug.
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Affiliation(s)
- P A Baede-van Dijk
- Section Clinical Assessments, Medicines Evaluation Board Agency, The Hague, the Netherlands
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Abstract
OBJECTIVE To report the first case of nelfinavir desensitization in an HIV patient who was intolerant to protease inhibitors. CASE SUMMARY A 43-year-old HIV-positive white man was treated with several protease inhibitors. The patient developed rashes in response to all protease inhibitors. His viral load was controlled only in the presence of a protease inhibitor. The patient tolerated nelfinavir longer than the other agents; therefore, the decision was made to attempt to desensitize him to nelfinavir. A six-hour inpatient protocol was used, and he tolerated the procedure without event. His disease is now well managed without recurrence of the rash. DISCUSSION The use of protease inhibitors has had a major impact on the morbidity and mortality of HIV-infected patients, Despite their benefits, this class of drugs is not without adverse effects. Allergic reactions in the form of rashes may develop, which can severely limit treatment options in HIV patients. We report the first case of rapid desensitization of nelfinavir in a patient who developed rashes to several protease inhibitors. CONCLUSIONS Intolerance to protease inhibitors due to rash is a well-documented phenomenon. In HIV patients, this can limit treatment options severely. This case demonstrates how desensitization to nefinavir can be performed successfully.
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Affiliation(s)
- P E Abraham
- Department of Pharmacy and Drug Information, Grady Health System, Atlanta, GA 30335-3801, USA.
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Abstract
Continually maintaining maximally suppressive drug concentrations represents a key defence against the emergence of resistance. If drug levels fall and replication occurs, the opportunity for mutant virus to be selected occurs. It has been increasingly recognized that variability in the pharmacokinetics of antiretrovirals, particularly protease inhibitors (PIs), means that drug exposure is not always optimal, giving the virus a chance to replicate. A significant number of patients receiving PIs two or three times daily will have trough (Ctrough or Cmin) plasma concentrations, which are close to, or below, the plasma protein binding-corrected inhibitory concentration (IC50 or IC95) during the dosing interval. It is primarily in this context that therapeutic drug monitoring of PIs has been proposed as an aid to patient management, to ensure that patients maintain adequate drug concentrations throughout the dosing interval. Ideally, an antiretroviral drug will have a pharmacokinetic (PK) profile that maintains drug levels well above the viral inhibitory concentration throughout the entire dosing interval. Beneficial drug-drug interactions have been shown to improve PI pharmacokinetics. Ritonavir (RTV) inhibits the key enzymes that limit the bioavailability or speed the metabolism of other PIs. It is therefore increasingly used for boosting and maintaining PI plasma concentrations. At low (100 mg twice a day) doses it acts as a pharmacoenhancer of indinavir (IDV), amprenavir, saquinavir, lopinavir and to a more limited degree nelfinavir. Using a pharmacoenhancer with a PI results in increased exposure to the PI, higher Cmin levels, and in most cases prolonged elimination half-lives. The long-term clinical benefits of PK enhancing are unknown as are the long-term toxicities, although the incidence of nephrolithiasis with IDV appears increased when IDV is combined with low-dose RTV in HIV-infected patients. Head-to-head clinical comparisons of boosted PI regimens will help answer some of the questions that remain with regard to PK enhancement.
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Affiliation(s)
- G J Moyle
- Chelsea and Westminster Hospital, London and University of Liverpool, Liverpool, UK.
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Paci-Bonaventure S, Hafi A, Vincent I, Quertainmont Y, Goujard C, Charpentier B, Taburet AM. Lack of removal of nelfinavir during a haemodialysis session in an HIV-1 infected patient with hepatic and renal insufficiency. Nephrol Dial Transplant 2001; 16:642-3. [PMID: 11239052 DOI: 10.1093/ndt/16.3.642] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Dronda F, Casado JL, Moreno S, Hertogs K, García-Arata I, Antela A, Pérez-Elías MJ, Ruiz L, Larder B. Phenotypic cross-resistance to nelfinavir: the role of prior antiretroviral therapy and the number of mutations in the protease gene. AIDS Res Hum Retroviruses 2001; 17:211-5. [PMID: 11177403 DOI: 10.1089/088922201750063124] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Cross-resistance to nelfinavir (NFV) is observed in patients failing protease inhibitor (PI)-containing therapies. We performed a study with 111 patients who started an NFV-based salvage regimen after failing PI-based therapy to evaluate genotypic changes and to identify factors associated with resistance to NFV. Genotypic and phenotypic resistance data at entry (111 and 51 samples) and after NFV failure (74 and 31 samples) were available. Median CD4(+) cell count was 208 x 10(6)/liter, HIV RNA level was 4.6 log(10) copies/ml, and median number of mutations in the protease was 9. At baseline, 51 and 14% of viral isolates showed high or intermediate phenotypic resistance to NFV. Phenotypic data correlated with virological outcome, reaching undetectability at the third month in 40, 14, and 0% of those patients with susceptible, intermediate, or resistant viral isolates, respectively. Phenotypic resistance to NFV was associated with the presence of the L90M mutation: 46% for resistant vs. 6% in susceptible strains. The number of mutations in the protease correlated with the fold-increase in the IC(50)-NFV. The D30N mutation was detected in only 1 of 74 patients who failed. In a logistic regression analysis, the number of mutations in the protease was associated with NFV cross-resistance (RR, 2.09 per each additional mutation; 95% CI 1.23-3.55; p < 0.01). In conclusion, phenotypic cross-resistance to NFV for PI-experienced patients can be predicted by the number of mutations in the protease. The L90M mutation is significantly associated with the subsequent failure of NFV-containing regimens. The presence of the D30N mutation was rare and not useful in identifying NFV-resistant isolates.
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Affiliation(s)
- F Dronda
- Infectious Disease Service, Hospital Ramón y Cajal, Madrid, Spain.
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42
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Abstract
The HIV-1 protease inhibitor (PI) saquinavir is available as a soft gelatin capsule (SGC) formulation. At the recommended dosage of saquinavir SGC (1200mg 3 times daily), this formulation provides around 8-fold greater exposure than the established hard gelatin capsule (HGC) formulation at the recommended dosage of 600mg 3 times daily. As with the HGC formulation, the most common adverse events seen with saquinavir SGC are gastrointestinal symptoms (e.g. diarrhoea, abdominal discomfort and nausea). Some of these may occur with a slightly higher frequency with the SGC than with the HGC formulation. Saquinavir SGC has only a minimal effect on nonfasting serum lipid and cholesterol levels. Like other PIs, saquinavir is metabolised by the cytochrome P450 (CYP) 3A4 isoenzyme and is susceptible to interactions with inducers (e.g. rifabutin and rifampicin) and inhibitors (e.g. clarithromycin and ketoconazole) of this enzyme. Ritonavir, nelfinavir, indinavir and delavirdine, all CYP3A4 inhibitors, greatly increase saquinavir plasma concentrations and the therapeutic implications of these interactions continue to be evaluated. While saquinavir is the least potent CYP 3A inhibitor among the PIs, several drugs (notably terfenadine, astemizole and cisapride) should not be given in combination with saquinavir. Therefore, although the SGC formulation enhances saquinavir exposure, it has a similar safety profile to the HGC formulation.
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Affiliation(s)
- J Gill
- Southern Alberta HIV Clinic, Foothills Hospital, Calgary, Canada.
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Amsden GW, Nafziger AN, Foulds G, Cabelus LJ. A Study of the Pharmacokinetics of Azithromycin and Nelfinavir When Coadministered in Healthy Volunteers. J Clin Pharmacol 2000. [DOI: 10.1177/009127000004001226] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Guy W. Amsden
- Clinical Pharmacology Research Center, Bassett Healthcare, Cooperstown, New York
- Research Institute, Bassett Healthcare, Cooperstown, New York
- Department of Medicine, Bassett Healthcare, Cooperstown, New York
- Department of Pharmacy, Bassett Healthcare, Cooperstown, New York
| | - Anne N. Nafziger
- Clinical Pharmacology Research Center, Bassett Healthcare, Cooperstown, New York
- Research Institute, Bassett Healthcare, Cooperstown, New York
- Department of Medicine, Bassett Healthcare, Cooperstown, New York
| | - George Foulds
- Department of Central Research Division, Pfizer, Inc., Groton, Connecticut
| | - Laura J. Cabelus
- Clinical Pharmacology Research Center, Bassett Healthcare, Cooperstown, New York
- Research Institute, Bassett Healthcare, Cooperstown, New York
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Vavro CL, Zimmermann AM, McClernon DR, Kehne SL, Martel LA, Valentine ME, McKinney RE. Virologic response of nine therapy-experienced children receiving 64 weeks of nelfinavir salvage therapy. Ann N Y Acad Sci 2000; 918:381-5. [PMID: 11131731 DOI: 10.1111/j.1749-6632.2000.tb05512.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- C L Vavro
- Department of Virology, Glaxo Wellcome, Inc., Research Triangle Park, North Carolina 27709, USA
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Gyllensten K, Sönnerborg A, Ståhle L. Switching antiretroviral therapy from an enzyme-inducing drug. Ther Drug Monit 2000; 22:637-8. [PMID: 11034274 DOI: 10.1097/00007691-200010000-00023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- K Gyllensten
- Department of Infectious Diseases, Karolinska Institute, Huddinge University Hospital, Sweden
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Abstract
As we enter the new millennium, there have been dramatic improvements in the care of patients with HIV infection. These have prolonged life and decreased morbidity and mortality. There are fourteen currently available antiretrovirals approved in the United States for the treatment of this infection. The medications, including their pharmacokinetic properties, side effects, and dosing are reviewed. In addition, the current approach to the use of these medicines is discussed.
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Affiliation(s)
- R Samuel
- Section of Infectious Diseases, Temple University Hospital, Philadelphia 19140, USA
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47
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Schmidt B, Walter H, Moschik B, Paatz C, van Vaerenbergh K, Vandamme AM, Schmitt M, Harrer T, Uberla K, Korn K. Simple algorithm derived from a geno-/phenotypic database to predict HIV-1 protease inhibitor resistance. AIDS 2000; 14:1731-8. [PMID: 10985309 DOI: 10.1097/00002030-200008180-00007] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Resistance against protease inhibitors (PI) can either be analysed genotypically or phenotypically. However, the interpretation of genotypic data is difficult, particularly for PI, because of the unknown contributions of several mutations to resistance and cross-resistance. OBJECTIVE Development of an algorithm to predict PI phenotype from genotypic data. METHODS Recombinant viruses containing patient-derived protease genes were analysed for sensitivity to indinavir, saquinavir, ritonavir and nelfinavir. Drug resistance-associated mutations were determined by direct sequencing. geno- and phenotypic data were compared for 119 samples from 97 HIV-1 infected patients. RESULTS Samples with one or two mutations in the gene for the protease were phenotypically sensitive in 74.3%, whereas 83.6% of samples with five or more mutations were resistant against all PI tested. Some mutations (361, 63P, 71V/T, 771) were frequent both in sensitive and resistant samples, whereas others (241, 30N, 461/L, 48V, 54V, 82A/F/T/S, 84V, 90M) were predominantly present in resistant samples. Therefore, the presence or absence of a single drug resistance-associated mutation predicted phenotypic PI resistance with high sensitivity (96.5-100%) but low specificity (13.3-57.4%). A more specific algorithm was obtained by taking into account the total number of drug resistance-associated mutations in the gene for the protease and restricting these to certain key positions for the PI. The algorithm was subsequently validated by analysis of 72 independent samples. CONCLUSION With an optimized algorithm, phenotypic PI resistance can be predicted by viral genotype with good sensitivity (89.1-93.0%) and specificity (82.6-93.3%). The reliability and relevance of this algorithm should be further evaluated in clinical practice.
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Affiliation(s)
- B Schmidt
- Institute of Clinical and Molecular Virology, German National Reference Centre for Retroviruses, University of Erlangen-Nürnberg, Erlangen
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Figgitt DP, Plosker GL. Saquinavir soft-gel capsule: an updated review of its use in the management of HIV infection. Drugs 2000; 60:481-516. [PMID: 10983742 DOI: 10.2165/00003495-200060020-00016] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
UNLABELLED Saquinavir is a potent and highly selective HIV protease inhibitor. Initially formulated as a hard-gel capsule (HGC), saquinavir was the first protease inhibitor available commercially for the treatment of patients with HIV infection. The limited oral bioavailability of saquinavir HGC has been improved significantly with the introduction of a soft-gel capsule (SGC) formulation. Saquinavir SGC displays greater than dose-proportional pharmacokinetics and mean area under the plasma concentration-time curve (AUC) values are 8- to 10-fold higher with saquinavir SGC 1200 mg 3 times daily than with the HGC formulation 600 mg 3 times daily, the recommended dosages of the 2 formulations. In combination with other protease inhibitors (particularly "low dose" ritonavir), the oral bioavailability of saquinavir (as either the HGC or SGC formulation) is markedly increased, allowing for reduced dosing frequency and/or dosage. The efficacy and tolerability of once- or twice-daily saquinavir SGC/"low dose" ritonavir combinations are currently being evaluated in patients with HIV infection. Data (up to 48 weeks) from noncomparative and comparative clinical trials evaluating saquinavir SGC-containing combination regimens in adult patients with HIV infection, support and strengthen the clinical efficacy profile of the drug that was demonstrated in initial trials. In antiretroviral therapy-naive and -experienced patients, saquinavir SGC combined with > or =2 nucleoside reverse transcriptase inhibitors (NRTIs), or nelfinavir, or nelfinavir plus 2 NRTIs or nonnucleoside reverse transcriptase inhibitors (NNRTIs), markedly improved immunological and virological surrogate markers (increased mean CD4+ cell counts and decreased mean plasma HIV RNA levels) of HIV infection. Saquinavir SGC demonstrated a trend to greater antiviral efficacy (measured by improvements in surrogate markers) than the HGC formulation (not statistically significant); a significantly greater proportion of patients treated with saquinavir SGC had plasma HIV RNA levels <400 copies/ml than patients receiving the HGC formulation. In the first direct comparison of 2 protease inhibitors, saquinavir SGC plus 2 NRTIs demonstrated similar antiviral efficacy to indinavir plus 2 NRTIs in patients with HIV infection (almost all of whom were antiretroviral therapy-naive); at 24 weeks, a significantly greater increase in CD4+ cell count from baseline was obtained in the saquinavir SGC group compared with the indinavir group, although this difference was not apparent at week 32. Triple therapy with saquinavir SGC plus 2 NRTIs was as effective as nelfinavir-containing triple therapy, or quadruple therapy (saquinavir SGC plus 2 NRTIs plus nelfinavir) in markedly suppressing HIV RNA levels in antiretroviral therapy-experienced or -naive patients. Saquinavir SGC is generally well tolerated. Gastrointestinal disturbances (generally nausea, diarrhoea, abdominal pain, vomiting and dyspepsia of moderate or greater intensity) are the most common adverse events associated with saquinavir SGC-containing therapy. In comparative trials, saquinavir SGC-containing therapy was as well tolerated as indinavir- and nelfinavir-containing therapy; although there were no statistical differences between treatment groups, the incidence of diarrhoea was lower in patients receiving saquinavir SGC compared with nelfinavir, saquinavir SGC plus nelfinavir (all combined with 2 NRTIs) or saquinavir SGC plus nelfinavir without additional therapy. Compared with the HGC formulation, saquinavir SGC appears to be associated with a higher overall incidence of adverse events. CONCLUSIONS Clinical trial data have shown that as part of triple or quadruple combination therapy, saquinavir SGC is an effective and generally well tolerated protease inhibitor in antiretroviral therapy-naive or -experienced patients with HIV infection. (ABSTRACT TRUNCATED)
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Affiliation(s)
- D P Figgitt
- Adis International Limited, Mairangi Bay, Auckland, New Zealand.
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Lenhard JM, Furfine ES, Jain RG, Ittoop O, Orband-Miller LA, Blanchard SG, Paulik MA, Weiel JE. HIV protease inhibitors block adipogenesis and increase lipolysis in vitro. Antiviral Res 2000; 47:121-9. [PMID: 10996400 DOI: 10.1016/s0166-3542(00)00102-9] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
AIDS therapies employing HIV protease inhibitors (PIs) are associated with changes in fat metabolism. However, the cellular mechanisms affected by PIs are not clear. Thus, the affects of PIs on adipocyte differentiation were examined in vitro using C3H10T1/2 stem cells. In these cells the PIs, nelfinavir, saquinavir, and ritonavir, reduced triglyceride accumulation, lipogenesis, and expression of the adipose markers, aP2 and LPL. Histological analysis revealed nelfinavir, saquinavir and ritonavir treatment decreased oil red O-staining of cytoplasmic fat droplets. Inhibition occurred in the presence of the RXR agonist LGD1069, indicating the inhibitory effects were not due to an absence of RXR ligand. Moreover, these three PIs increased acute lipolysis in adipocytes. In contrast, two HIV PIs, amprenavir and indinavir, had little effect on lipolysis, lipogenesis, or expression of aP2 and LPL. Although, saquinavir, inhibited ligand-binding to PPARgamma with an IC(50) of 12.7+/-3.2 microM, none of the other PIs bound to the nuclear receptors RXRalpha or PPARgamma, (IC(50)s>20 microM), suggesting that inhibition of adipogenesis is not due to antagonism of ligand binding to RXRalpha or PPARgamma. Taken together, the results suggest that some, but not all, PIs block adipogenesis and stimulate fat catabolism in vitro and this may contribute to the effects of PIs on metabolism in the clinic.
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Affiliation(s)
- J M Lenhard
- Department of Metabolic Diseases, Glaxo Wellcome Inc., 5 Moore Drive, Research Triangle Park, NC 27709, USA.
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Muirhead GJ, Wulff MB, Fielding A, Kleinermans D, Buss N. Pharmacokinetic interactions between sildenafil and saquinavir/ritonavir. Br J Clin Pharmacol 2000; 50:99-107. [PMID: 10930961 PMCID: PMC2014393 DOI: 10.1046/j.1365-2125.2000.00245.x] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AIMS To investigate the effect of the antiretroviral protease inhibitors saquinavir (soft gelatin capsule) and ritonavir on the pharmacokinetic properties and tolerability of sildenafil and to investigate the effect of sildenafil on the steady-state pharmacokinetics of saquinavir and ritonavir. METHODS Two independent, 8 day, open, randomized, placebo-controlled, parallel-group studies (containing a double-blind crossover phase) were conducted at Pfizer Clinical research units (Canterbury, UK. and Brussels, Belgium). Twenty-eight healthy male volunteers entered each study. In each study, volunteers were randomized (n = 14 per group) to receive sildenafil on day 1 followed by a 7-day treatment period (days 2-8) with saquinavir or placebo (Study I) or ritonavir or placebo (Study II). Sildenafil or placebo (Study I and Study II) was administered alternately on day 7 or day 8, depending on initial randomization. The effect of saquinavir and ritonavir on the pharmacokinetics of sildenafil and its primary circulating metabolite (UK-103, 320) and the effect of single-dose sildenafil on the steady-state pharmacokinetics of saquinavir (1200 mg three times daily) and ritonavir (500 mg twice daily) were determined. The safety and tolerability of sildenafil coadministered with saquinavir or ritonavir were also assessed. RESULTS Both protease inhibitors significantly increased Cmax, AUC, tmax and t(1/2) values for both sildenafil and UK-103, 320. Ritonavir showed a significantly greater effect than saquinavir with increases in sildenafil AUC and Cmax of 11-fold (95% CI: 9.0, 12.0) and 3.9-fold (95% CI: 3.2, 4.9), respectively. This compared with increases of 3.1-fold (95% CI: 2.5, 4.0) and 2.4-fold (95% CI: 1.8, 3.3) for coadministration with saquinavir. In contrast, the steady-state pharmacokinetics of saquinavir and ritonavir were unaffected by sildenafil. The increases in systemic exposure to sildenafil and UK-103, 320 were not associated with an increased incidence of adverse events or clinically significant changes in blood pressure, heart rate or ECG parameters. CONCLUSIONS These results indicate that both saquinavir and ritonavir modify the pharmacokinetics of sildenafil presumably through inhibition of CYP3A4. The more pronounced effect of ritonavir may be attributed to its additional potent inhibition of CYP2C9. No change in safety or tolerability was observed when sildenafil was coadministered with either protease inhibitor. However, given the extent of the interactions, a lower sildenafil starting dose (25 mg) should be considered for patients receiving saquinavir and it is recommended not to exceed a maximum single dose of 25 mg in a 48 h period for patients receiving ritonavir.
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Affiliation(s)
- G J Muirhead
- Early Clinical Research Group, Pfizer Central Research, Sandwich, Kent, UK.
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