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Sun Y, Wu X, Zuo P, Liu Z, Miao X, Liu J, Wen H. Synthesis and mutagenic risk of avanafil's potential genotoxic impurities. RSC Adv 2024; 14:21432-21438. [PMID: 38979469 PMCID: PMC11228755 DOI: 10.1039/d4ra02345e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Accepted: 06/24/2024] [Indexed: 07/10/2024] Open
Abstract
In the technical route for the synthesis of avanafil, 1-ethyl-(3-dimethylaminopropyl)carbamyldiimide hydrochloride (EDCI) and 1-hydroxybenzotriazole (HOBT) are used as reactive acid-amine binding agents. HOBT contains trace amounts of hydrazine residue, and there is a risk of introducing potentially mutagenic impurities with hydrazide-containing structures. The potentially genotoxic impurities E (Imp-E) and F (Imp-F) of avanafil with altering hydrazide-structure were synthesized by chemical method; subsequently, the impurities were evaluated and classified according to ICH M7 guidelines. Two complementary quantitative structure-activity relationship (QSAR) evaluation systems (Derek and Sarah) based on expert rules and statistics were used to preliminarily predict the genotoxicity of Imp-E and Imp-F, and the prediction result of E was suspected to be positive. In the Ames test of Imp-E and Imp-F, in the dose range of 62.5-1000 μg per plate, with or without the presence of metabolic activation system S9, the number of revertant colonies did not exceed 2 times the number of colonies in the solvent control group and did not show a dose-response relationship, and the test results were negative. Imp-E and Imp-F were determined to be negative for genotoxicity, which could be controlled as class 5 in ICH M7, that is, non mutagenic impurity.
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Affiliation(s)
- Yunkai Sun
- School of Chemical Engineering and Materials, Changzhou Institute of Technology Changzhou 213022 China
- School of Chemistry and Chemical Engineering, University of South China Hengyang 421001 China
| | - Xiaoxia Wu
- School of Chemistry and Chemical Engineering, University of South China Hengyang 421001 China
- Harvest Pharmaceutical Co., Ltd Changsha 410000 China
| | - Pei Zuo
- Harvest Pharmaceutical Co., Ltd Changsha 410000 China
| | - Zhao Liu
- Harvest Pharmaceutical Co., Ltd Changsha 410000 China
| | - Xuepei Miao
- School of Chemical Engineering and Materials, Changzhou Institute of Technology Changzhou 213022 China
| | - Jian Liu
- School of Chemical Engineering and Materials, Changzhou Institute of Technology Changzhou 213022 China
| | - Hairuo Wen
- National Center for Safety Evaluation of Drugs, National Institutes for Food and Drug Control, Key Laboratory of Beijing for Nonclinical Safety Evaluation Research of Drugs Beijing 100176 P. R. China
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2
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Zhang D, Song J, Cai M, Li Y, Wu Y. Preliminary study on the enhanced bioremediation of PAH-contaminated soil in Beijing and assessment of remediation effects based on toxicity tests. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2024; 46:103. [PMID: 38436752 DOI: 10.1007/s10653-024-01913-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Accepted: 02/13/2024] [Indexed: 03/05/2024]
Abstract
In this study, we focused on soil contaminated by polycyclic aromatic hydrocarbons (PAHs) at typical coking-polluted sites in Beijing, conducted research on enhanced PAH bioremediation and methods to evaluate remediation effects based on toxicity testing, and examined changes in pollutant concentrations during ozone preoxidation coupled with biodegradation in test soil samples. The toxicity of mixed PAHs in soil was directly evaluated using the Ames test, and the correlation between mixed PAH mutagenicity and benzo(a)pyrene (BaP) toxicity was investigated in an effort to establish a carcinogenic risk assessment model based on biological toxicity tests to evaluate remediation effects on PAH-contaminated soil. This study provides a theoretical and methodological foundation for evaluating the effect of bioremediation on PAH-contaminated soil at industrially contaminated sites. The results revealed that the removal rate of PAHs after 5 min of O3 preoxidation and 4 weeks of soil reaction with saponin surfactants and medium was 83.22%. The soil PAH extract obtained after remediation had a positive effect on the TA98 strain at a dose of 2000 μg·dish-1, and the carcinogenic risk based on the Ames toxicity test was 8.98 times greater than that calculated by conventional carcinogenic PAH toxicity parameters. The total carcinogenic risk of the remediated soil samples was approximately one order of magnitude less than that of the original soil samples.
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Affiliation(s)
- Dan Zhang
- Beijing Municipal Research Institute of Eco-Environmental Protection, Beijing, 100037, China.
- National Engineering Research Centre of Urban Environmental Pollution Control, Beijing, 100037, China.
- Beijing Key Laboratory for Risk Modeling and Remediation of Contaminated Sites, Beijing, 100037, China.
| | - Jinmei Song
- Beijing Municipal Research Institute of Eco-Environmental Protection, Beijing, 100037, China
- National Engineering Research Centre of Urban Environmental Pollution Control, Beijing, 100037, China
- Beijing Key Laboratory for Risk Modeling and Remediation of Contaminated Sites, Beijing, 100037, China
- College of Resources, Environment and Tourism, Capital Normal University, Beijing, 100048, China
| | - Minqi Cai
- Beijing Municipal Research Institute of Eco-Environmental Protection, Beijing, 100037, China
- National Engineering Research Centre of Urban Environmental Pollution Control, Beijing, 100037, China
- Beijing Key Laboratory for Risk Modeling and Remediation of Contaminated Sites, Beijing, 100037, China
| | - Yandan Li
- Beijing Municipal Research Institute of Eco-Environmental Protection, Beijing, 100037, China
- National Engineering Research Centre of Urban Environmental Pollution Control, Beijing, 100037, China
- Beijing Key Laboratory for Risk Modeling and Remediation of Contaminated Sites, Beijing, 100037, China
| | - Yang Wu
- Beijing Municipal Research Institute of Eco-Environmental Protection, Beijing, 100037, China
- National Engineering Research Centre of Urban Environmental Pollution Control, Beijing, 100037, China
- Beijing Key Laboratory for Risk Modeling and Remediation of Contaminated Sites, Beijing, 100037, China
- College of Resources, Environment and Tourism, Capital Normal University, Beijing, 100048, China
- Beijing Capital Air Environmental Science & Technology Co., Ltd., Beijing, 100044, China
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3
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Lambré C, Barat Baviera JM, Bolognesi C, Cocconcelli PS, Crebelli R, Gott DM, Grob K, Lampi E, Mengelers M, Mortensen A, Rivière G, Steffensen I, Tlustos C, Van Loveren H, Vernis L, Zorn H, Glandorf B, Herman L, Aguilera J, Andryszkiewicz M, Gomes A, Kovalkovicova N, Liu Y, Rainieri S, Chesson A. Scientific Guidance for the submission of dossiers on Food Enzymes. EFSA J 2021; 19:e06851. [PMID: 34721697 PMCID: PMC8529584 DOI: 10.2903/j.efsa.2021.6851] [Citation(s) in RCA: 141] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Following a request from the European Commission, EFSA developed an updated scientific guidance to assist applicants in the preparation of applications for food enzymes. This guidance describes the scientific data to be included in applications for the authorisation of food enzymes, as well as for the extension of use for existing authorisations, in accordance with Regulation (EC) No 1331/2008 and its implementing rules. Information to be provided in applications relates to source, production and characteristics of the food enzyme, toxicological data, allergenicity and dietary exposure estimation. Source, production and characteristics of the food enzyme are first considered only for enzymes of microbial origin and subsequently for those enzymes derived from plants and for enzymes from animal sources. Finally, the data requested for toxicology, allergenicity and dietary exposure applies to all food enzymes independent of the source. On the basis of the submitted data, EFSA will assess the safety of food enzymes and conclude whether or not they present a risk to human health under the proposed conditions of use.
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4
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Pinter E, Friedl C, Irnesberger A, Czerny T, Piwonka T, Peñarroya A, Tacker M, Riegel E. HepGentox: a novel promising HepG2 reportergene-assay for the detection of genotoxic substances in complex mixtures. PeerJ 2021; 9:e11883. [PMID: 34395098 PMCID: PMC8323594 DOI: 10.7717/peerj.11883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 07/09/2021] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND In risk assessment, genotoxicity is a key factor to determine the safety for the consumer. Most in vitro genotoxicity assays were developed for the assessment of pure substances. However, in recent years more attention has been given to complex mixtures, where usually low amounts of a substance are present. For high-throughput screening, a toxicologically sensitive assay should be used, covering a broad range of genotoxic substances and detecting them at low concentrations. HepG2 cells have been recommended as one of the prime candidates for genotoxicity testing, as they are p53 competent, less prone towards cytotoxic effects and tend to have some metabolic activity. METHODS A HepG2 liver cell line was characterized for its suitability for genotoxicity assessment. For this, a luciferase based reporter gene assay revolving around the p53 pathway was validated for the analysis of pure substances and of complex mixtures. Further, the cell's capability to detect genotoxins correctly with and without an exogenous metabolizing system, namely rat liver S9, was assessed. RESULTS The assay proved to have a high toxicological sensitivity (87.5%) and specificity (94%). Further, the endogenous metabolizing system of the HepG2 cells was able to detect some genotoxins, which are known to depend on an enzymatic system. When complex mixtures were added this did not lead to any adverse effects concerning the assays performance and cytotoxicity was not an issue. DISCUSSION The HepGentox proved to have a high toxicological sensitivity and specificity for the tested substances, with similar or even lower lowest effective concentration (LEC) values, compared to other regulatory mammalian assays. This combines some important aspects in one test system, while also being less time and material consuming and covering several genotoxicity endpoints. As the assay performs well with and without an exogenous metabolizing system, no animal liver fractions have to be used, which application is discussed controversially and is considered to be expensive and laborious in sample testing. Because of this, the HepGentox is suitable for a cost-efficient first screening approach to obtain important information with human cells for further approaches, with a relatively fast and easy method. Therefore, the HepGentox is a promising assay to detect genotoxic substances correctly in complex mixtures even at low concentrations, with the potential for a high throughput application. In a nutshell, as part of an in vitro bioassay test battery, this assay could provide valuable information for complex mixtures.
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Affiliation(s)
- Elisabeth Pinter
- Departement of Applied Life Sciences, University of Applied Sciences Vienna, FH Campus Wien, Vienna, Austria
| | - Christina Friedl
- Departement of Applied Life Sciences, University of Applied Sciences Vienna, FH Campus Wien, Vienna, Austria
| | - Alexandra Irnesberger
- Departement of Applied Life Sciences, University of Applied Sciences Vienna, FH Campus Wien, Vienna, Austria
| | - Thomas Czerny
- Departement of Applied Life Sciences, University of Applied Sciences Vienna, FH Campus Wien, Vienna, Austria
| | - Tina Piwonka
- Departement of Applied Life Sciences, University of Applied Sciences Vienna, FH Campus Wien, Vienna, Austria
| | - Alfonso Peñarroya
- Departement of Applied Life Sciences, University of Applied Sciences Vienna, FH Campus Wien, Vienna, Austria
| | - Manfred Tacker
- Departement of Applied Life Sciences, University of Applied Sciences Vienna, FH Campus Wien, Vienna, Austria
| | - Elisabeth Riegel
- Departement of Applied Life Sciences, University of Applied Sciences Vienna, FH Campus Wien, Vienna, Austria
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Rajana N, Ramana D, Ganta RR, Devi DR, Deshpande AA, Babu JM, Basavaiah K. An orthogonal approach for method development and validation of three potential halo alkyl alcohol genotoxic impurities in miglitol drug substance by fast gas chromatography–mass spectrometry. SEPARATION SCIENCE PLUS 2020. [DOI: 10.1002/sscp.202000050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Nagaraju Rajana
- Technology Development Center, Custom Pharmaceutical Services Dr. Reddy's Laboratories Ltd Miyapur India
- Department of Inorganic & Analytical Chemistry Andhra University Visakhapatnam India
| | - D.V. Ramana
- Technology Development Center, Custom Pharmaceutical Services Dr. Reddy's Laboratories Ltd Miyapur India
| | - Rama Rao Ganta
- Technology Development Center, Custom Pharmaceutical Services Dr. Reddy's Laboratories Ltd Miyapur India
| | | | - Amol A. Deshpande
- Technology Development Center, Custom Pharmaceutical Services Dr. Reddy's Laboratories Ltd Miyapur India
| | - J. Moses Babu
- Integrated Product Development Organization, Dr. Reddy's Laboratories Innovation Plaza Bachupally India
| | - K. Basavaiah
- Department of Inorganic & Analytical Chemistry Andhra University Visakhapatnam India
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6
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Mutagenicity evaluation of pesticide analogs using standard and 6-well miniaturized bacterial reverse mutation tests. Toxicol In Vitro 2020; 69:105006. [PMID: 32976929 DOI: 10.1016/j.tiv.2020.105006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 09/11/2020] [Accepted: 09/21/2020] [Indexed: 11/21/2022]
Abstract
The Ames test is widely used in the mutagenicity evaluation of new and existing chemicals as a part of a compound selection strategy, regulatory control, the equivalence assessment, carcinogenic potential measurement etc. Intensification of the chemical industry and synthesis of plenty of new molecules has led to the necessity of tests with a higher throughput capacity. The 6-well miniaturized bacterial reverse mutation test and the standard Ames test were compared using 14 technical grade active ingredients (TGAIs) of pesticides. With some exceptions, the responses obtained in the miniscreen Ames are similar to those seen in the standard method: 4 overall test outcomes were negative and 9 were positive in both test versions, but 1 discordant result between the miniscreen and standard version. Comparison of the standard and the miniscreen Ames test resulted in 98% of concordance across five strains and conditions (±S9). The overall judgment is that the miniscreen Ames test can be used to assess the mutagenicity of pesticide analogs. It has the advantage of decreasing the number of materials and animals (for S9) and keeping a high-test performance.
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7
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Dillon GP, Keegan JD, Moran CA. Toxicological evaluation of an unextracted Aurantiochytrium limacinum biomass, a novel docosahexaenoic acid rich feed ingredient. Food Chem Toxicol 2020; 141:111397. [PMID: 32413458 DOI: 10.1016/j.fct.2020.111397] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 04/28/2020] [Accepted: 04/30/2020] [Indexed: 10/24/2022]
Abstract
The purpose of this paper was to evaluate the toxicological potential of a heterotrophically grown unextracted Aurantiochytrium limacinum biomass (AURA) when used as a food additive. The following toxicological assessments were conducted on this novel docosahexaenoic acid rich feed ingredient: Mutagenic activity was tested by means of the Ames' test using five Salmonella typhimurium strains; clastogenic activity was investigated using the micronucleus test in male and female Sprague Dawley rats; genotoxic activity was assessed by means of the in vitro metaphase analysis tests in human lymphocytes; oral toxicity was tested by administration of AURA at various concentrations; eye and skin irritation was assessed in rabbits according to OECD guidelines; skin sensitivity was established in guinea pigs by means of the Buehler test. All conducted tests were considered valid under the experimental conditions. No significant mutagenic activity or clastogenic activity was observed. Genotoxic activity in human lymphocytes was not induced. Oral administration of 276 mg AURA/kg bw1 and 2000 mg AURA/kg bw resulted in no mortality or signs of acute toxicity. Daily administration of 1000 mg AURA/kg bw caused no mortality or biologically relevant signs of toxicity and was established as the No Observable Adverse Effect Level. AURA was also found to be a non-irritant for the eye and skin of the rabbit and was non-sensitizing to guinea pig skin.
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Affiliation(s)
- G P Dillon
- Alltech Ireland, Sarney, Summerhill Road, Dunboyne, Co Meath, Ireland.
| | - J D Keegan
- Alltech Ireland, Sarney, Summerhill Road, Dunboyne, Co Meath, Ireland
| | - C A Moran
- Alltech France SARL, Rue Charles Amand, 14500, Vire, France
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8
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Pinter E, Rainer B, Czerny T, Riegel E, Schilter B, Marin-Kuan M, Tacker M. Evaluation of the Suitability of Mammalian In Vitro Assays to Assess the Genotoxic Potential of Food Contact Materials. Foods 2020; 9:foods9020237. [PMID: 32098342 PMCID: PMC7074469 DOI: 10.3390/foods9020237] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 02/12/2020] [Accepted: 02/19/2020] [Indexed: 01/25/2023] Open
Abstract
Background: Non-targeted screening of food contact materials (FCM) for non-intentionally added substances (NIAS) reveals a great number of unknown and unidentified substances present at low concentrations. In the absence of toxicological data, the application of the threshold of toxicological concern (TTC) or of EU Regulation 10/2011 requires methods able to fulfill safety threshold criteria. In this review, mammalian in vitro genotoxicity assays are analyzed for their ability to detect DNA-damaging substances at limits of biological detection (LOBD) corresponding to the appropriate safety thresholds. Results: The ability of the assays to detect genotoxic effects varies greatly between substance classes. Especially for direct-acting mutagens, the assays lacked the ability to detect most DNA reactive substances below the threshold of 10 ppb, making them unsuitable to pick up potential genotoxicants present in FCM migrates. However, suitability for the detection of chromosomal damage or investigation of other modes of action makes them a complementary tool as part of a standard test battery aimed at giving additional information to ensure safety. Conclusion: improvements are necessary to comply with regulatory thresholds to consider mammalian genotoxicity in vitro assays to assess FCM safety.
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Affiliation(s)
- Elisabeth Pinter
- Department of Applied Life Sciences, University of Applied Sciences, FH Campus Wien, Helmut-Qualtinger-Gasse 2, 1030 Vienna, Austria
- Correspondence: ; Tel.: +43-1-606-6877-3584
| | - Bernhard Rainer
- Department of Applied Life Sciences, University of Applied Sciences, FH Campus Wien, Helmut-Qualtinger-Gasse 2, 1030 Vienna, Austria
| | - Thomas Czerny
- Department of Applied Life Sciences, University of Applied Sciences, FH Campus Wien, Helmut-Qualtinger-Gasse 2, 1030 Vienna, Austria
| | - Elisabeth Riegel
- Department of Applied Life Sciences, University of Applied Sciences, FH Campus Wien, Helmut-Qualtinger-Gasse 2, 1030 Vienna, Austria
| | - Benoît Schilter
- Nestlé Research Center, Route du Jorat 57, 1000 Lausanne, Switzerland
| | | | - Manfred Tacker
- Department of Applied Life Sciences, University of Applied Sciences, FH Campus Wien, Helmut-Qualtinger-Gasse 2, 1030 Vienna, Austria
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Zeller A, Brigo A, Brink A, Guerard M, Lang D, Muster W, Runge F, Sutter A, Vock E, Wichard J, Schadt S. Genotoxicity Assessment of Drug Metabolites in the Context of MIST and Beyond. Chem Res Toxicol 2019; 33:10-19. [DOI: 10.1021/acs.chemrestox.9b00348] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Andreas Zeller
- Roche Pharmaceutical Research & Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Alessandro Brigo
- Roche Pharmaceutical Research & Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Andreas Brink
- Roche Pharmaceutical Research & Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Melanie Guerard
- Roche Pharmaceutical Research & Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Dieter Lang
- Bayer AG, Pharmaceuticals, Research Center Aprath, 42096 Wuppertal, Germany
| | - Wolfgang Muster
- Roche Pharmaceutical Research & Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Frank Runge
- Boehringer Ingelheim Pharma GmbH & Co. KG, Birkendorfer Strasse 65, 88400 Biberach, Germany
| | - Andreas Sutter
- Bayer AG, Pharmaceuticals, Research Center Aprath, 42096 Wuppertal, Germany
| | - Esther Vock
- Boehringer Ingelheim Pharma GmbH & Co. KG, Birkendorfer Strasse 65, 88400 Biberach, Germany
| | - Jörg Wichard
- Bayer AG, Pharmaceuticals, Research Center Aprath, 42096 Wuppertal, Germany
| | - Simone Schadt
- Roche Pharmaceutical Research & Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Grenzacherstrasse 124, 4070 Basel, Switzerland
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Schilter B, Burnett K, Eskes C, Geurts L, Jacquet M, Kirchnawy C, Oldring P, Pieper G, Pinter E, Tacker M, Traussnig H, Van Herwijnen P, Boobis A. Value and limitation of in vitro bioassays to support the application of the threshold of toxicological concern to prioritise unidentified chemicals in food contact materials. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2019; 36:1903-1936. [PMID: 31550212 DOI: 10.1080/19440049.2019.1664772] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Some of the chemicals in materials used for packaging food may leak into the food, resulting in human exposure. These include so-called Non-intentionally Added Substances (NIAS), many of them being unidentified and toxicologically uncharacterized. This raises the question of how to address their safety. An approach consisting of identification and toxicologically testing all of them appears neither feasible nor necessary. Instead, it has been proposed to use the threshold of toxicological concern (TTC) Cramer class III to prioritise unknown NIAS on which further safety investigations should focus. Use of the Cramer class III TTC for this purpose would be appropriate if amongst others sufficient evidence were available that the unknown chemicals were not acetylcholinesterase inhibitors or direct DNA-reactive mutagens. While knowledge of the material and analytical chemistry may efficiently address the first concern, the second could not be addressed in this way. An alternative would be use of a bioassay capable of detecting DNA-reactive mutagens at very low levels. No fully satisfactory bioassay was identified. The Ames test appeared the most suitable since it specifically detects DNA-reactive mutagens and the limit of biological detection of highly potent genotoxic carcinogens is low. It is proposed that for a specific migrate, the evidence for absence of mutagenicity based on the Ames test, together with analytical chemistry and information on packaging manufacture could allow application of the Cramer class III TTC to prioritise unknown NIAS. Recommendations, as well as research proposals, have been developed on sample preparation and bioassay improvement with the ultimate aim of improving limits of biological detection of mutagens. Although research is still necessary, the proposed approach should bring significant benefits over the current practices used for safety evaluation of food contact materials.
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Affiliation(s)
- Benoit Schilter
- Food Safety Research Department, Nestlé Research, Vers-chez-les-Blanc, Switzerland
| | | | - Chantra Eskes
- Services & Consultations on Alternative Methods (SeCAM), Magliaso, Switzerland and Swiss 3R Competence Centre (3RCC), Bern, Switzerland
| | - Lucie Geurts
- International Life Sciences Institute Europe, Brussels, Belgium
| | - Mélanie Jacquet
- Danone Food Safety Center, Danone S.A., Danone Food Safety Center, Palaiseau, France
| | - Christian Kirchnawy
- Technical Competence Center, OFI - Austrian Research Institute for Chemistry and Technology, Vienna, Austria
| | | | | | - Elisabeth Pinter
- Department of Applied Life Sciences, University of Applied Sciences, Vienna, Austria
| | - Manfred Tacker
- Department of Applied Life Sciences, University of Applied Sciences, Vienna, Austria
| | | | | | - Alan Boobis
- Department of Medicine, Imperial College London, London, UK
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11
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Holland D, Pfuhler S. Assessment of the sensitivity of the Ames Assay to pick up true mutagens at concentrations lower than the maximum OECD TG471 guideline dose. Toxicol Lett 2018. [DOI: 10.1016/j.toxlet.2018.06.753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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12
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Rainer B, Pinter E, Czerny T, Riegel E, Kirchnawy C, Marin-Kuan M, Schilter B, Tacker M. Suitability of the Ames test to characterise genotoxicity of food contact material migrates. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2018; 35:2230-2243. [PMID: 30257137 DOI: 10.1080/19440049.2018.1519259] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Non-intentionally added substances (NIAS) are chemical impurities which can migrate from packaging materials (FCM) into food. Safety assessment of NIAS is required by European law, but currently there is no comprehensive testing strategy available. In this context, one key element is to get insight on the potential presence of genotoxic NIAS in FCM migrates. This raises questions about the limit at which genotoxins can be detected in complex mixtures such as FCM migrates, and if such limits of detection (LOD) would be compatible with safety. In this context, the present review assesses the suitability of the Ames assay to address genotoxicity of FCM migrates. Lowest effective concentrations of packaging-related and other chemicals in test media were retrieved from scientific literature and used as surrogates of LODs to be benchmarked against a value of 0.01 mg kg-1 (10 ppb) in migrates. This is a pragmatic threshold used in FCM safety evaluation to prioritise substances requiring proper identification and risk assessment. The analysis of the data shows that only potent genotoxins can theoretically be detectable at a level of 0.01 mg kg-1 in migrates or food. Only a minority (10%) of genotoxic chemicals reported to be associated with FCMs could be picked up at a level of 0.01 mg kg-1 or lower. Overall, this review shows that the Ames test in its present form cannot be used as standalone method for evaluating the genotoxic potential of FCM migrates, but must be used together with other information from analytical chemistry and FCM manufacturing.
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Affiliation(s)
- Bernhard Rainer
- a Department of Applied Life Sciences , University of Applied Sciences, FH Campus Wien , Vienna , Austria
| | - Elisabeth Pinter
- a Department of Applied Life Sciences , University of Applied Sciences, FH Campus Wien , Vienna , Austria
| | - Thomas Czerny
- a Department of Applied Life Sciences , University of Applied Sciences, FH Campus Wien , Vienna , Austria
| | - Elisabeth Riegel
- a Department of Applied Life Sciences , University of Applied Sciences, FH Campus Wien , Vienna , Austria
| | - Christian Kirchnawy
- b Department for Microbiology and Cell Culture , OFI - Austrian Research Institute for Chemistry and Technology , Vienna , Austria
| | - Maricel Marin-Kuan
- c Chemical Food Safety , Nestlé Research Center , Lausanne , Switzerland
| | - Benoît Schilter
- c Chemical Food Safety , Nestlé Research Center , Lausanne , Switzerland
| | - Manfred Tacker
- a Department of Applied Life Sciences , University of Applied Sciences, FH Campus Wien , Vienna , Austria
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13
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Dobo KL, Cheung JR, Gunther WC, Kenyon MO. 2-Hydroxypyridine-N-oxide (HOPO): Equivocal in the ames assay. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2018; 59:312-321. [PMID: 29481708 DOI: 10.1002/em.22179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 02/01/2018] [Accepted: 02/07/2018] [Indexed: 06/08/2023]
Abstract
2-Hydroxypyridine-N-oxide (HOPO) is a useful coupling reagent for synthesis of active pharmaceutical ingredients. It has been reported to be weakly mutagenic in the Ames assay (Ding W et al. []: J Chromatogr A 1386:47-52). According to the ICH M7 guidance (2014) regarding control of mutagenic impurities to limit potential carcinogenic risk, mutagens require control in drug substances such that exposure not exceeds the threshold of toxicological concern. Given the weak response observed in the Ames assay and the lack of any obvious structural features that could confer DNA reactivity we were interested to determine if the results were reproducible and investigate the role of potentially confounding experimental parameters. Specifically, Ames tests were conducted to assess the influence of compound purity, solvent choice, dose spacing, toxicity, type of S9 (aroclor vs phenobarbital/β-napthoflavone), and lot variability on the frequency of HOPO induced revertant colonies. Initial extensive testing using one lot of HOPO produced no evidence of mutagenic potential in the Ames assays. Subsequent studies with four additional lots produced conflicting results, with an ∼2.0-fold increase in revertant colonies observed. Given the rigor of the current investigation, lack of reproducibility between lots, and the weak increase in revertants, it is concluded that HOPO is equivocal in the bacterial reverse mutation assay. It is highly unlikely that HOPO poses a mutagenic risk in vivo; therefore, when it is used as a reagent in pharmaceutical synthesis, it should not be regarded as a mutagenic impurity, but rather a normal process related impurity. Environ. Mol. Mutagen. 59:312-321, 2018. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Krista L Dobo
- Pfizer Worldwide Research and Development, Drug Safety, Genetic Toxicology Center of Emphasis, Groton, Connecticut, 06340
| | - Jennifer R Cheung
- Pfizer Worldwide Research and Development, Drug Safety, Genetic Toxicology Center of Emphasis, Groton, Connecticut, 06340
| | - William C Gunther
- Pfizer Worldwide Research and Development, Drug Safety, Genetic Toxicology Center of Emphasis, Groton, Connecticut, 06340
| | - Michelle O Kenyon
- Pfizer Worldwide Research and Development, Drug Safety, Genetic Toxicology Center of Emphasis, Groton, Connecticut, 06340
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14
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Gunther WC, Kenyon MO, Cheung JR, Dugger RW, Dobo KL. Resolution of contradiction between in silico predictions and Ames test results for four pharmaceutically relevant impurities. Regul Toxicol Pharmacol 2017; 91:68-76. [PMID: 29061373 DOI: 10.1016/j.yrtph.2017.10.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 10/09/2017] [Accepted: 10/17/2017] [Indexed: 10/18/2022]
Abstract
The ICH M7 Guideline requires low level control of mutagenic impurities in pharmaceutical products to minimize cancer risk in patients (ICHM7, 2014). Bacterial mutagenicity (Ames) data is generally used to determine mutagenic and possible carcinogenic potential of compounds. Recently, a publication on experiences of using two in silico systems to identify potentially mutagenic impurities highlighted the importance of performing a critical review of published Ames data utilized as part of a mutagenicity assessment of impurities (Greene et al., 2015). Four compounds (2-amino-5-hydroxybenzoic acid, 2-amino-3-chlorobenzoic acid, methyl 2-amino-4-chlorobenzoate and 4-morpholinopyridine) reported mutagenic were identified in a two system in silico assessment and expert review of the structuresas non-mutagenic. Likely reasons for mutagenicity could not be identified and the purity of the compounds tested was proposed. In the current investigation, the purest available sample of the four compounds was tested in an OECD-compliant Ames test. The compounds were all found to be non-mutagenic. Possible reasons for the discrepancy between previously reported and current results are discussed. Additionally, important points to consider when conducting an expert review of available Ames data are provided particularly in cases where reported Ames results are discrepant with a two system in silico assessment.
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15
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Emerce E, Cok I, Degim IT. Determination of the impurities in drug products containing montelukast and in silico/in vitro genotoxicological assessments of sulfoxide impurity. Toxicol Lett 2015. [PMID: 26205398 DOI: 10.1016/j.toxlet.2015.07.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Impurities affecting safety, efficacy, and quality of pharmaceuticals are of increasing concern for regulatory agencies and pharmaceutical industries, since genotoxic impurities are understood to play important role in carcinogenesis. The study aimed to analyse impurities of montelukast chronically used in asthma theraphy and perform genotoxicological assessment considering regulatory approaches. Impurities (sulfoxide, cis-isomer, Michael adducts-I&II, methylketone, methylstyrene) were quantified using RP-HPLC analysis on commercial products available in Turkish market. For sulfoxide impurity, having no toxicity data and found to be above the qualification limit, in silico mutagenicity prediction analysis, miniaturized bacterial gene mutation test, mitotic index determination and in vitro chromosomal aberration test w/wo metabolic activation system were conducted. In the analysis of different batches of 20 commercial drug products from 11 companies, only sulfoxide impurity exceeded qualification limit in pediatric tablets from 2 companies and in adult tablets from 7 companies. Leadscope and ToxTree programs predicted sulfoxide impurity as nonmutagenic. It was also found to be nonmutagenic in Ames MPF Penta I assay. Sulfoxide impurity was dose-dependent cytotoxic in human peripheral lymphocytes, however, it was found to be nongenotoxic. It was concluded that sulfoxide impurity should be considered as nonmutagenic and can be classified as ordinary impurity according to guidelines.
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Affiliation(s)
- Esra Emerce
- Gazi University, Pharmacy Faculty, Toxicology Department, Ankara, Turkey.
| | - Ismet Cok
- Gazi University, Pharmacy Faculty, Toxicology Department, Ankara, Turkey
| | - I Tuncer Degim
- Gazi University, Pharmacy Faculty, Pharmaceutical Technology Department, Ankara, Turkey
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16
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Reddy AVB, Jaafar J, Umar K, Majid ZA, Aris AB, Talib J, Madhavi G. Identification, control strategies, and analytical approaches for the determination of potential genotoxic impurities in pharmaceuticals: A comprehensive review. J Sep Sci 2015; 38:764-79. [DOI: 10.1002/jssc.201401143] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 12/12/2014] [Accepted: 12/16/2014] [Indexed: 11/06/2022]
Affiliation(s)
| | - Jafariah Jaafar
- Department of Chemistry; Faculty of Science; Universiti Teknologi Malaysia; Johor Malaysia
| | - Khalid Umar
- Department of Environmental Engineering; Faculty of Civil Engineering; Universiti Teknologi Malaysia; Johor Malaysia
| | - Zaiton Abdul Majid
- Department of Chemistry; Faculty of Science; Universiti Teknologi Malaysia; Johor Malaysia
| | - Azmi Bin Aris
- Department of Environmental Engineering; Faculty of Civil Engineering; Universiti Teknologi Malaysia; Johor Malaysia
| | - Juhaizah Talib
- Department of Environmental Engineering; Faculty of Civil Engineering; Universiti Teknologi Malaysia; Johor Malaysia
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17
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Wiesner J. Challenges of safety evaluation. JOURNAL OF ETHNOPHARMACOLOGY 2014; 158 Pt B:467-470. [PMID: 25150528 DOI: 10.1016/j.jep.2014.08.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 06/23/2014] [Accepted: 08/07/2014] [Indexed: 06/03/2023]
Abstract
Each application for authorisation of a medicinal product must be accompanied by the particulars and documents referred to in Directive 2001/83/EC on the Community code relating to medicinal products for human use. Details on the documentation needed for traditional herbal medicinal products (THMP) are given in article 16c of the above mentioned Directive. It is pointed out that a bibliographic review of safety data together with an expert report and additional data, if necessary, are required. The Committee on Herbal Medicinal Products (HMPC) provides in its "Guideline on the use of the CTD format in the preparation of a registration application for traditional herbal medicinal products" (EMA/HMPC/71049/2007 Rev. 1) guidance on how to present the information and the dossier needed for an application. There, in agreement with the Directive 2001/83/EC, a bibliographical review of safety data is required within the "Non-clinical Overview". However, it is assumable that for such products, with a long tradition of usage bibliographical information relating to non-clinical safety are available, even if incomplete or not in accordance with today׳s state of the art. In the "Guideline on non-clinical documentation for herbal medicinal products in applications for marketing authorisation (bibliographical and mixed applications) and in applications for simplified registration" (EMEA/HMPC/32116/2005) it is reflected how to deal with such an incomplete set of data for traditional herbal medicinal products and crucial information are highlighted. This article will focus on the explanation of the requirements needed for the non-clinical safety evaluation of THMPs and some detailed explanations of the performance and interpretation of the mutagenicity studies.
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Affiliation(s)
- Jacqueline Wiesner
- Federal Institute for Drugs and Medical Devices, K.-G.-Kiesinger-Allee 3, 53175 Bonn, Germany.
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18
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Deýlová D, Vyskočil V, Barek J. Voltammetric determination of 2-amino-6-nitrobenzothiazole and 5-nitrobenzimidazole using a silver solid amalgam electrode modified by a microcrystalline natural graphite–polystyrene composite film. J Electroanal Chem (Lausanne) 2014. [DOI: 10.1016/j.jelechem.2014.01.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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19
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Hornberg JJ, Laursen M, Brenden N, Persson M, Thougaard AV, Toft DB, Mow T. Exploratory toxicology as an integrated part of drug discovery. Part II: Screening strategies. Drug Discov Today 2013; 19:1137-44. [PMID: 24374152 DOI: 10.1016/j.drudis.2013.12.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 11/18/2013] [Accepted: 12/18/2013] [Indexed: 12/31/2022]
Abstract
In an effort to reduce toxicity-related attrition, different strategies have been implemented throughout the pharmaceutical industry. Previously (in Part I), we have outlined our 'integrated toxicology' strategy, which aims to provide timely go/no-go decisions (fail early) but also to show a direction to the drug discovery teams (showing what will not fail). In this review (Part II of the series) we describe our compound testing strategies with respect to cardiovascular safety, hepatotoxicity, genotoxicity, immunotoxicity and exploratory in vivo toxicity. We discuss the in vitro, ex vivo and in vivo assays and models we employ to assess safety risks and optimize compound series during the drug discovery process, including their predictivity and the decisions they generate.
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Affiliation(s)
- Jorrit J Hornberg
- Department of Exploratory Toxicology, H. Lundbeck A/S, Ottiliavej 9, DK-2500 Valby, Denmark
| | - Morten Laursen
- Department of Exploratory Toxicology, H. Lundbeck A/S, Ottiliavej 9, DK-2500 Valby, Denmark
| | - Nina Brenden
- Department of Exploratory Toxicology, H. Lundbeck A/S, Ottiliavej 9, DK-2500 Valby, Denmark
| | - Mikael Persson
- Department of Exploratory Toxicology, H. Lundbeck A/S, Ottiliavej 9, DK-2500 Valby, Denmark
| | - Annemette V Thougaard
- Department of Exploratory Toxicology, H. Lundbeck A/S, Ottiliavej 9, DK-2500 Valby, Denmark
| | - Dorthe B Toft
- Department of Exploratory Toxicology, H. Lundbeck A/S, Ottiliavej 9, DK-2500 Valby, Denmark
| | - Tomas Mow
- Department of Exploratory Toxicology, H. Lundbeck A/S, Ottiliavej 9, DK-2500 Valby, Denmark.
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Zhu Q, Li T, Wei X, Li J, Wang W. In silico and in vitro genotoxicity evaluation of descarboxyl levofloxacin, an impurity in levofloxacin. Drug Chem Toxicol 2013; 37:311-5. [PMID: 24224725 DOI: 10.3109/01480545.2013.851691] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
It is important to establish the safety of impurities in drug substances or drug products. The assessment of genotoxicity of impurities and the determination of acceptable limits for genotoxic impurities was addressed in some recent guidances as a difficult issue. Descarboxyl levofloxacin is an impurity isolated from levofloxacin, which may impose a risk without associated benefit. However, there is insufficient toxic information about descarboxyl levofloxacin. This study investigated the genotoxicity of this impurity by in silico and in vitro methods. We used Derek, a commercial structure-activity relationship software package, as an in silico tool. The results showed that there was a structural alert (quinoline) in this impurity. Then, the in vitro genotoxicity of descarboxyl levofloxacin was investigated by a modified Ames test and by a chromosomal aberration test, using Chinese hamster lung (CHL) cells. Both assays were conducted in the presence or absence of S-9 mix. The results showed that the test impurity was not mutagenic in the Ames test (31.25-500 μg/plate). Whereas there was a statistically significant increase in the number of metaphase CHL cells with structural aberrations at the concentration of 1 mg/mL with S-9 mix, the aberrations rate was 7.5%. It did not significantly increase the number of structural aberration in CHL cells in the presence (at 250 and 500 μg/mL) or absence of S-9 mix. Based on these assays, descarboxyl levofloxacin could be controlled as a nongenotoxic impurity.
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Affiliation(s)
- Qingfen Zhu
- Shandong Institute for Food and Drug Control , Jinan , China
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21
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Klenke E. Development of genotoxic impurities guidelines and their impact on regulatory review. Toxicol Lett 2013. [DOI: 10.1016/j.toxlet.2013.06.053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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22
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Determination of compound-specific acceptable daily intakes for 11 mutagenic carcinogens used in pharmaceutical synthesis. Regul Toxicol Pharmacol 2013; 65:201-13. [DOI: 10.1016/j.yrtph.2012.11.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 11/16/2012] [Accepted: 11/21/2012] [Indexed: 11/23/2022]
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23
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Deýlová D, Vyskočil V, Barek J, Economou A. Bismuth film electrode at a silver solid amalgam substrate as a new tool for voltammetric determination of electrochemically reducible organic compounds. Talanta 2012. [DOI: 10.1016/j.talanta.2012.07.044] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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24
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Valerio, LG, Cross KP. Characterization and validation of an in silico toxicology model to predict the mutagenic potential of drug impurities*. Toxicol Appl Pharmacol 2012; 260:209-21. [DOI: 10.1016/j.taap.2012.03.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Revised: 02/24/2012] [Accepted: 03/02/2012] [Indexed: 10/28/2022]
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25
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Deýlová D, Vyskočil V, Barek J. Voltammetric determination of 2-amino-6-nitrobenzothiazole at two different silver amalgam electrodes. Electrochim Acta 2012. [DOI: 10.1016/j.electacta.2011.12.033] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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26
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McCarren P, Springer C, Whitehead L. An investigation into pharmaceutically relevant mutagenicity data and the influence on Ames predictive potential. J Cheminform 2011; 3:51. [PMID: 22107807 PMCID: PMC3277490 DOI: 10.1186/1758-2946-3-51] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Accepted: 11/22/2011] [Indexed: 11/29/2022] Open
Abstract
Background In drug discovery, a positive Ames test for bacterial mutation presents a significant hurdle to advancing a drug to clinical trials. In a previous paper, we discussed success in predicting the genotoxicity of reagent-sized aryl-amines (ArNH2), a structure frequently found in marketed drugs and in drug discovery, using quantum mechanics calculations of the energy required to generate the DNA-reactive nitrenium intermediate (ArNH:+). In this paper we approach the question of what molecular descriptors could improve these predictions and whether external data sets are appropriate for further training. Results In trying to extend and improve this model beyond this quantum mechanical reaction energy, we faced considerable difficulty, which was surprising considering the long history and success of QSAR model development for this test. Other quantum mechanics descriptors were compared to this reaction energy including AM1 semi-empirical orbital energies, nitrenium formation with alternative leaving groups, nitrenium charge, and aryl-amine anion formation energy. Nitrenium formation energy, regardless of the starting species, was found to be the most useful single descriptor. External sets used in other QSAR investigations did not present the same difficulty using the same methods and descriptors. When considering all substructures rather than just aryl-amines, we also noted a significantly lower performance for the Novartis set. The performance gap between Novartis and external sets persists across different descriptors and learning methods. The profiles of the Novartis and external data are significantly different both in aryl-amines and considering all substructures. The Novartis and external data sets are easily separated in an unsupervised clustering using chemical fingerprints. The chemical differences are discussed and visualized using Kohonen Self-Organizing Maps trained on chemical fingerprints, mutagenic substructure prevalence, and molecular weight. Conclusions Despite extensive work in the area of predicting this particular toxicity, work in designing and publishing more relevant test sets for compounds relevant to drug discovery is still necessary. This work also shows that great care must be taken in using QSAR models to replace experimental evidence. When considering all substructures, a random forest model, which can inherently cover distinct neighborhoods, built on Novartis data and previously reported external data provided a suitable model.
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Affiliation(s)
- Patrick McCarren
- Novartis Institutes for Biomedical Research, 100 Technology Square, Cambridge, MA 02139, USA.
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Giordani A, Kobel W, Gally HU. Overall impact of the regulatory requirements for genotoxic impurities on the drug development process. Eur J Pharm Sci 2011; 43:1-15. [PMID: 21420491 DOI: 10.1016/j.ejps.2011.03.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Revised: 01/18/2011] [Accepted: 03/05/2011] [Indexed: 11/19/2022]
Abstract
In the last decade a considerable effort has been made both by the regulators and the pharmaceutical industry to assess genotoxic impurities (GTI) in pharmaceutical products. Though the control of impurities in drug substances and products is a well established and consolidated procedure, its extension to GTI has given rise to a number of problems, both in terms of setting the limits and detecting these impurities in pharmaceutical products. Several papers have dealt with this issue, discussing available regulations, providing strategies to evaluate the genotoxic potential of chemical substances, and trying to address the analytical challenge of detecting GTI at trace levels. In this review we would like to discuss the available regulations, the toxicological background for establishing limits, as well as the analytical approaches used for GTI assessment. The final aim is that of providing a complete overview of the topic with updated available information, to address the overall GTI issue during the development of new drug substances.
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28
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Liu DQ, Sun M, Kord AS. Recent advances in trace analysis of pharmaceutical genotoxic impurities. J Pharm Biomed Anal 2010; 51:999-1014. [DOI: 10.1016/j.jpba.2009.11.009] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Revised: 11/03/2009] [Accepted: 11/08/2009] [Indexed: 10/20/2022]
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29
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Robinson DI. Control of Genotoxic Impurities in Active Pharmaceutical Ingredients: A Review and Perspective. Org Process Res Dev 2010. [DOI: 10.1021/op900341a] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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