<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Publishing DTD v1.3 20210610//EN" "JATS-journalpublishing1-3.dtd">
<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">pharmjournal</journal-id><journal-title-group><journal-title xml:lang="ru">Разработка и регистрация лекарственных средств</journal-title><trans-title-group xml:lang="en"><trans-title>Drug development &amp; registration</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2305-2066</issn><issn pub-type="epub">2658-5049</issn><publisher><publisher-name>LLC «CPHA»</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.33380/2305-2066-2023-12-1-215-226</article-id><article-id custom-type="elpub" pub-id-type="custom">pharmjournal-1452</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>ДОКЛИНИЧЕСКИЕ И КЛИНИЧЕСКИЕ ИССЛЕДОВАНИЯ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>PRECLINICAL AND CLINICAL STUDIES</subject></subj-group></article-categories><title-group><article-title>Совместное определение основного метаболита молнупиравира (β-D-N4-гидроксицитидина) и фавипиравира в плазме крови человека методом ВЭЖХ-МС/МС</article-title><trans-title-group xml:lang="en"><trans-title>Simultaneous Determination of Major Molnupiravir Metabolite (β-D-N4-hydroxycytidine) and Favipiravir in Human Plasma by HPLC-MS/MS</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-8354-7877</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Комаров</surname><given-names>Т. Н.</given-names></name><name name-style="western" xml:lang="en"><surname>Komarov</surname><given-names>T. N.</given-names></name></name-alternatives><bio xml:lang="ru"><p>117246, г. Москва, Научный пр., д. 20, стр. 3</p></bio><bio xml:lang="en"><p>20/3, Nauchny proezd, Moscow, 117246</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-7518-0777</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Карнакова</surname><given-names>П. К.</given-names></name><name name-style="western" xml:lang="en"><surname>Karnakova</surname><given-names>P. K.</given-names></name></name-alternatives><bio xml:lang="ru"><p>117246, г. Москва, Научный пр., д. 20, стр. 3</p></bio><bio xml:lang="en"><p>20/3, Nauchny proezd, Moscow, 117246</p></bio><email xlink:type="simple">p.karnakova@cpha.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-6621-1060</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Арчакова</surname><given-names>О. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Archakova</surname><given-names>O. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>117246, г. Москва, Научный пр., д. 20, стр. 3</p></bio><bio xml:lang="en"><p>20/3, Nauchny proezd, Moscow, 117246</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-4894-7001</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Щелгачева</surname><given-names>Д. С.</given-names></name><name name-style="western" xml:lang="en"><surname>Shchelgacheva</surname><given-names>D. S.</given-names></name></name-alternatives><bio xml:lang="ru"><p>117246, г. Москва, Научный пр., д. 20, стр. 3</p></bio><bio xml:lang="en"><p>20/3, Nauchny proezd, Moscow, 117246</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-7496-8186</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Багаева</surname><given-names>Н. С.</given-names></name><name name-style="western" xml:lang="en"><surname>Bagaeva</surname><given-names>N. S.</given-names></name></name-alternatives><bio xml:lang="ru"><p>117246, г. Москва, Научный пр., д. 20, стр. 3</p></bio><bio xml:lang="en"><p>20/3, Nauchny proezd, Moscow, 117246</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-1185-8630</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Шохин</surname><given-names>И. Е.</given-names></name><name name-style="western" xml:lang="en"><surname>Shohin</surname><given-names>I. E.</given-names></name></name-alternatives><bio xml:lang="ru"><p>117246, г. Москва, Научный пр., д. 20, стр. 3</p></bio><bio xml:lang="en"><p>20/3, Nauchny proezd, Moscow, 117246</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-7348-9412</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Заславская</surname><given-names>К. Я.</given-names></name><name name-style="western" xml:lang="en"><surname>Zaslavskaya</surname><given-names>K. Ya.</given-names></name></name-alternatives><bio xml:lang="ru"><p>129090, г. Москва, пр-т Мира, д. 13 стр. 1</p></bio><bio xml:lang="en"><p>13/1, Prospekt Mira, Moscow, 129090</p></bio><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-5998-4874</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Белый</surname><given-names>П. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Bely</surname><given-names>P. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>129090, г. Москва, пр-т Мира, д. 13 стр. 1</p></bio><bio xml:lang="en"><p>13/1, Prospekt Mira, Moscow, 129090</p></bio><xref ref-type="aff" rid="aff-2"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ООО «Центр Фармацевтической Аналитики» (ООО «ЦФА»)</institution></aff><aff xml:lang="en"><institution>LLC "CPHA"</institution></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>ООО «ПРОМОМЕД РУС»</institution></aff><aff xml:lang="en"><institution>LLC "PROMOMED RUS"</institution></aff></aff-alternatives><pub-date pub-type="collection"><year>2023</year></pub-date><pub-date pub-type="epub"><day>28</day><month>02</month><year>2023</year></pub-date><volume>12</volume><issue>1</issue><fpage>215</fpage><lpage>226</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Комаров Т.Н., Карнакова П.К., Арчакова О.А., Щелгачева Д.С., Багаева Н.С., Шохин И.Е., Заславская К.Я., Белый П.А., 2023</copyright-statement><copyright-year>2023</copyright-year><copyright-holder xml:lang="ru">Комаров Т.Н., Карнакова П.К., Арчакова О.А., Щелгачева Д.С., Багаева Н.С., Шохин И.Е., Заславская К.Я., Белый П.А.</copyright-holder><copyright-holder xml:lang="en">Komarov T.N., Karnakova P.K., Archakova O.A., Shchelgacheva D.S., Bagaeva N.S., Shohin I.E., Zaslavskaya K.Y., Bely P.A.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.pharmjournal.ru/jour/article/view/1452">https://www.pharmjournal.ru/jour/article/view/1452</self-uri><abstract><sec><title>Введение</title><p>Введение. Новая коронавирусная инфекция [Coronavirus Disease 2019 (COVID-19)] – острое инфекционное заболевание, вызываемое вирусом SARS-CoV-2 (Severe acute respiratory syndrome-related coronavirus 2), которое продолжает представлять серьезную опасность для здоровья. Молнупиравир и фавипиравир – противовирусные препараты с анти-РНК-полимеразной активностью, одобренные Министерством здравоохранения Российской Федерации для лечения COVID-19. Разработка и валидация методики совместного определения метаболита молнупиравира β-D-N4-гидроксицитидина и фавипиравира в плазме крови человека является необходимой процедурой для проведения аналитической части клинического исследования с целью дальнейшего изучения фармакокинетики.</p></sec><sec><title>Цель</title><p>Цель. Целью исследования является разработка и валидация методики совместного определения β-D-N4-гидроксицитидина и фавипиравира в плазме крови человека методом высокоэффективной жидкостной хроматографии с тандемным масс-селективным детектированием (ВЭЖХ-МС/МС) для дальнейшего изучения фармакокинетики молнупиравира и фавипиравира.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы. Определение β-D-N4-гидроксицитидина и фавипиравира в плазме крови человека проводили методом ВЭЖХ-МС/МС. В качестве пробоподготовки был использован способ осаждения белков 0,1 % раствором муравьиной кислоты в ацетонитриле. Внутренний стандарт: прометазин. Подвижная фаза: аммонийно-формиатный буфер 0,01 моль/л (Элюент А), 0,1 % муравьиной кислоты, 10 % воды в ацетонитриле с прибавлением 0,08 % аммиака (Элюент В). Колонка: Shim-pack GWS C18, 150 × 4,6 мм, 5 мкм. Аналитический диапазон методики: 50,00–10000,00 нг/мл для β-D-N4-гидроксицитидина, 250,00–20000,00 нг/мл для фавипиравира в плазме крови. Источник ионизации: электроспрей. Условия детектирования: 260,00 m/z → 82,10 m/z, 260,00 m/z → 111,00 m/z, 260,00 m/z → 127,95 m/z (β-D-N4-гидроксицитидин); 156,15 m/z → 65,95 m/z, 156,15 m/z → 85,00 m/z, 156,15 m/z → 113,10 m/z (фавипиравир); 285,05 m/z → 198,05 m/z (прометазин).</p></sec><sec><title>Результаты и обсуждение</title><p>Результаты и обсуждение. Разработанная методика была валидирована по следующим параметрам: селективность, пригодность стандартного образца, эффект матрицы, калибровочная кривая, точность, прецизионность, степень извлечения, нижний предел количественного определения перенос пробы, стабильность.</p></sec><sec><title>Заключение</title><p>Заключение. Разработана и валидирована методика совместного определения β-D-N4-гидроксицитидина и фавипиравира в плазме крови человека методом ВЭЖХ-МС/МС. Подтвержденный аналитический диапазон методики составил 50,00–10000,00 нг/мл для β-D-N4-гидроксицитидина и 250,00–20000,00 нг/мл для фавипиравира в плазме крови. Полученный аналитический диапазон позволяет применять разработанную методику для проведения фармакокинетических исследований комбинированных препаратов молнупиравира и фавипиравира.</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Introduction</title><p>Introduction. Coronavirus disease 2019 (COVID-19) is an infectious disease caused by the SARS-CoV-2 virus (severe acute respiratory syndrome-related coronavirus 2). COVID-19 is now expected to stay with us for many years as a recurring disease. Molnupiravir and favipiravir are oral antiviral drugs with anti-RNA polymerase activity. The Russian Health Ministry has approved molnupiravir and favipiravir for the treatment of COVID-19. The study describes development and validation of high-performance liquid chromatography – tandem mass spectrometry (HPLC-MS/MS) method for the simultaneous determination of β-D-N4-Hydroxycytidine and favipiravir in human blood plasma. The method could be applied in pharmacokinetic study of molnupiravir and favipiravir.</p></sec><sec><title>Aim</title><p>Aim. The aim of this study is to develop and validate a HPLC-MS/MS bioanalytical method for the determination of β-D-N4-Hydroxycytidine and favipiravir in human plasma.</p></sec><sec><title>Materials and methods</title><p>Materials and methods. The determination of β-D-N4-Hydroxycytidine and favipiravir in human plasma by HPLC-MS/MS. The samples were processed by 0.1 % formic acid in acetonitrile. Internal standard: promethazine. Mobile phase: 0.01 mol/L Ammonium formate buffer solution (Eluent A), 0.1 % formic acid and 0.08 % aqueous ammonia in water/acetonitrile 10 : 90 (Eluent B). Column: Shim-pack GWS C18, 150 × 4.6 mm, 5 μm. Analytical range: 50.00–10000.00 ng/mL for β-D-N4-Hydroxycytidine, 250.00–20000.00 ng/mL for favipiravir in human plasma. Ionization source: electrospray ionization. Detection conditions: 260.00 m/z → 82.10 m/z, 260.00 m/z → 111.00 m/z, 260.00 m/z → 127.95 m/z (β-D-N4-Hydroxycytidine); 156.15 m/z → 65.95 m/z, 156.15 m/z → 85.00 m/z, 156.15 m/z → 113.10 m/z (favipiravir); 285.05 m/z → 198.05 m/z (promethazine).</p></sec><sec><title>Results and discussion</title><p>Results and discussion. This method was validated by selectivity, suitability of reference standard, matrix effect, calibration curve, accuracy, precision, spike recovery, the lower limit of quantification, carry-over effect and stability.</p></sec><sec><title>Conclusion</title><p>Conclusion. The HPLC-MS/MS method for quantitative determination of β-D-N4-Hydroxycytidine and favipiravir in human plasma was developed and validated. The analytical range was 50.00–10000.00 ng/mL for β-D-N4-Hydroxycytidine, 250.00–20000.00 ng/mL for favipiravir in human plasma. This method was applied to investigate the pharmacokinetics of molnupiravir and favipiravir.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>β-D-N4-гидроксицитидин</kwd><kwd>NHС</kwd><kwd>молнупиравир</kwd><kwd>фавипиравир</kwd><kwd>COVID-19</kwd><kwd>плазма</kwd><kwd>ВЭЖХ-МС/МС</kwd><kwd>валидация</kwd><kwd>фармакокинетика</kwd></kwd-group><kwd-group xml:lang="en"><kwd>β-D-N4-Hydroxycytidine</kwd><kwd>NHC</kwd><kwd>molnupiravir</kwd><kwd>favipiravir</kwd><kwd>COVID-19</kwd><kwd>plasma</kwd><kwd>HPLC-MS/MS</kwd><kwd>validation</kwd><kwd>pharmacokinetics</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Li C. X., Noreen S., Zhang L. X., Saeed M., Wu P. F., Ijaz M., Dai D. F., Maqbool I., Madni A., Akram F., Naveed M. A critical analysis of SARS-CoV-2 (COVID-19) complexities, emerging variants, and therapeutic interventions and vaccination strategies. Biomedicine &amp; Pharmacotherapy. 2022;146:112550. DOI: 10.1016/j.biopha.2021.112550.</mixed-citation><mixed-citation xml:lang="en">Li C. X., Noreen S., Zhang L. X., Saeed M., Wu P. F., Ijaz M., Dai D. F., Maqbool I., Madni A., Akram F., Naveed M. A critical analysis of SARS-CoV-2 (COVID-19) complexities, emerging variants, and therapeutic interventions and vaccination strategies. Biomedicine &amp; Pharmacotherapy. 2022;146:112550. DOI: 10.1016/j.biopha.2021.112550.</mixed-citation></citation-alternatives></ref><ref id="cit2"><label>2</label><citation-alternatives><mixed-citation xml:lang="ru">Popovic M. XBB.1.5 Kraken Cracked: Gibbs Energies of Binding and Biosynthesis of the XBB.1.5 Variant of SARS-Cov-2. Preprints. 2023;2023010404. DOI: 10.20944/preprints202301.0404.v1.</mixed-citation><mixed-citation xml:lang="en">Popovic M. XBB.1.5 Kraken Cracked: Gibbs Energies of Binding and Biosynthesis of the XBB.1.5 Variant of SARS-Cov-2. Preprints. 2023;2023010404. DOI: 10.20944/preprints202301.0404.v1.</mixed-citation></citation-alternatives></ref><ref id="cit3"><label>3</label><citation-alternatives><mixed-citation xml:lang="ru">Parums D. V. The XBB. 1.5 (‘Kraken’) Subvariant of Omicron SARS-CoV-2 and its Rapid Global Spread. Medical Science Monitor: International Medical. Journal of Experimental and Clinical Research. 2023;29:e939580. DOI: 10.12659/MSM.939580.</mixed-citation><mixed-citation xml:lang="en">Parums D. V. The XBB. 1.5 (‘Kraken’) Subvariant of Omicron SARS-CoV-2 and its Rapid Global Spread. Medical Science Monitor: International Medical. Journal of Experimental and Clinical Research. 2023;29:e939580. DOI: 10.12659/MSM.939580.</mixed-citation></citation-alternatives></ref><ref id="cit4"><label>4</label><citation-alternatives><mixed-citation xml:lang="ru">Lee C. C., Hsieh C. C., Ko W. C. Molnupiravir — A Novel Oral Anti-SARS-CoV-2 Agent. Antibiotics. 2021;10:1294. DOI: 10.3390/antibiotics10111294.</mixed-citation><mixed-citation xml:lang="en">Lee C. C., Hsieh C. C., Ko W. C. Molnupiravir — A Novel Oral Anti-SARS-CoV-2 Agent. Antibiotics. 2021;10:1294. DOI: 10.3390/antibiotics10111294.</mixed-citation></citation-alternatives></ref><ref id="cit5"><label>5</label><citation-alternatives><mixed-citation xml:lang="ru">Pourkarim F., Pourtaghi-Anvarian S., Rezaee H. Molnupiravir: A new candidate for COVID-19 treatment. Pharmacology research &amp; perspectives. 2022;10(1):e00909. DOI: 10.1002/prp2.909.</mixed-citation><mixed-citation xml:lang="en">Pourkarim F., Pourtaghi-Anvarian S., Rezaee H. Molnupiravir: A new candidate for COVID-19 treatment. Pharmacology research &amp; perspectives. 2022;10(1):e00909. DOI: 10.1002/prp2.909.</mixed-citation></citation-alternatives></ref><ref id="cit6"><label>6</label><citation-alternatives><mixed-citation xml:lang="ru">Gordon C. J., Tchesnokov E. P., Schinazi R. F., Götte M. Molnupiravir promotes SARS-CoV-2 mutagenesis via the RNA template. Journal of Biological Chemistry. 2021;297(1):100770. DOI: 10.1016/j.jbc.2021.100770.</mixed-citation><mixed-citation xml:lang="en">Gordon C. J., Tchesnokov E. P., Schinazi R. F., Götte M. Molnupiravir promotes SARS-CoV-2 mutagenesis via the RNA template. Journal of Biological Chemistry. 2021;297(1):100770. DOI: 10.1016/j.jbc.2021.100770.</mixed-citation></citation-alternatives></ref><ref id="cit7"><label>7</label><citation-alternatives><mixed-citation xml:lang="ru">Sharaf Y. A., El Deeb S., Ibrahim A. E., Al-Harrasi A., Sayed R. A. Two green micellar HPLC and mathematically assisted UV spectroscopic methods for the simultaneous determination of molnupiravir and favipiravir as a novel combined COVID-19 antiviral regimen. Molecules. 2022;27(7):2330. DOI: 10.3390/molecules27072330.</mixed-citation><mixed-citation xml:lang="en">Sharaf Y. A., El Deeb S., Ibrahim A. E., Al-Harrasi A., Sayed R. A. Two green micellar HPLC and mathematically assisted UV spectroscopic methods for the simultaneous determination of molnupiravir and favipiravir as a novel combined COVID-19 antiviral regimen. Molecules. 2022;27(7):2330. DOI: 10.3390/molecules27072330.</mixed-citation></citation-alternatives></ref><ref id="cit8"><label>8</label><citation-alternatives><mixed-citation xml:lang="ru">Балакин К. В., Стороженко Р. В., Якубова Е. В. Фавипиравир как средство терапии COVID-19. Научный бюллетень ХимРар. 2023;1.</mixed-citation><mixed-citation xml:lang="en">Balakin K. V., Storozhenko R. V., Jakubova E. V. Favipiravir for the treatment of COVID-19. Nauchnyj bjulleten’ HimRar. 2023;1. (In Russ.)</mixed-citation></citation-alternatives></ref><ref id="cit9"><label>9</label><citation-alternatives><mixed-citation xml:lang="ru">Eloy P., Le Grand R., Malvy D., Guedj J. Combined treatment of molnupiravir and favipiravir against SARS-CoV-2 infection: One+ zero equals two? EBioMedicine. 2021;74:103663. DOI: 10.1016/j.ebiom.2021.103663.</mixed-citation><mixed-citation xml:lang="en">Eloy P., Le Grand R., Malvy D., Guedj J. Combined treatment of molnupiravir and favipiravir against SARS-CoV-2 infection: One+ zero equals two? EBioMedicine. 2021;74:103663. DOI: 10.1016/j.ebiom.2021.103663.</mixed-citation></citation-alternatives></ref><ref id="cit10"><label>10</label><citation-alternatives><mixed-citation xml:lang="ru">Gouda A. S., Marzouk H. M., Rezk M. R., Salem A. M., Morsi M. I., Nouman E. G., Abdallah Y. M., Hassan A. Y., Abdel-Megied A. M. A validated LC-MS/MS method for determination of antiviral prodrug molnupiravir in human plasma and its application for a pharmacokinetic modeling study in healthy Egyptian volunteers. Journal of Chromatography B. 2022;1206:123363. DOI: 10.1016/j.jchromb.2022.123363.</mixed-citation><mixed-citation xml:lang="en">Gouda A. S., Marzouk H. M., Rezk M. R., Salem A. M., Morsi M. I., Nouman E. G., Abdallah Y. M., Hassan A. Y., Abdel-Megied A. M. A validated LC-MS/MS method for determination of antiviral prodrug molnupiravir in human plasma and its application for a pharmacokinetic modeling study in healthy Egyptian volunteers. Journal of Chromatography B. 2022;1206:123363. DOI: 10.1016/j.jchromb.2022.123363.</mixed-citation></citation-alternatives></ref><ref id="cit11"><label>11</label><citation-alternatives><mixed-citation xml:lang="ru">Amara A., Penchala S. D., Else L., Hale C., FitzGerald R., Walker L., Lyons R., Fletcher T., Khoo S. The development and validation of a novel LC-MS/MS method for the simultaneous quantification of Molnupiravir and its metabolite ß-d-N4-hydroxycytidine in human plasma and saliva. Journal of pharmaceutical and biomedical analysis. 2021;206:114356. DOI: 10.1016/j.jpba.2021.114356.</mixed-citation><mixed-citation xml:lang="en">Amara A., Penchala S. D., Else L., Hale C., FitzGerald R., Walker L., Lyons R., Fletcher T., Khoo S. The development and validation of a novel LC-MS/MS method for the simultaneous quantification of Molnupiravir and its metabolite ß-d-N4-hydroxycytidine in human plasma and saliva. Journal of pharmaceutical and biomedical analysis. 2021;206:114356. DOI: 10.1016/j.jpba.2021.114356.</mixed-citation></citation-alternatives></ref><ref id="cit12"><label>12</label><citation-alternatives><mixed-citation xml:lang="ru">Parsons T. L., Kryszak L. A., Marzinke M. A. Development and validation of assays for the quantification of β-D-N4-hydroxycytidine in human plasma and β-D-N4-hydroxycytidine-triphosphate in peripheral blood mononuclear cell lysates. Journal of Chromatography B. 2021;1182:122921. DOI: 10.1016/j.jchromb.2021.122921.</mixed-citation><mixed-citation xml:lang="en">Parsons T. L., Kryszak L. A., Marzinke M. A. Development and validation of assays for the quantification of β-D-N4-hydroxycytidine in human plasma and β-D-N4-hydroxycytidine-triphosphate in peripheral blood mononuclear cell lysates. Journal of Chromatography B. 2021;1182:122921. DOI: 10.1016/j.jchromb.2021.122921.</mixed-citation></citation-alternatives></ref><ref id="cit13"><label>13</label><citation-alternatives><mixed-citation xml:lang="ru">Hailat M., Al-Ani I., Hamad M., Zakareia Z., Abu Dayyih W. Development and Validation of a Method for Quantification of Favipiravir as COVID-19 Management in Spiked Human Plasma. Molecules. 2021;26(13):3789. DOI: 10.3390/molecules26133789.</mixed-citation><mixed-citation xml:lang="en">Hailat M., Al-Ani I., Hamad M., Zakareia Z., Abu Dayyih W. Development and Validation of a Method for Quantification of Favipiravir as COVID-19 Management in Spiked Human Plasma. Molecules. 2021;26(13):3789. DOI: 10.3390/molecules26133789.</mixed-citation></citation-alternatives></ref><ref id="cit14"><label>14</label><citation-alternatives><mixed-citation xml:lang="ru">Abdallah I. A., Hammad S. F., Bedair A., Mansour F. R. Menthol-assisted homogenous liquid-liquid microextraction for HPLC/UV determination of favipiravir as an antiviral for COVID-19 in human plasma. Journal of Chromatography B. 2022;1189:123087. DOI: 10.1016/j.jchromb.2021.123087.</mixed-citation><mixed-citation xml:lang="en">Abdallah I. A., Hammad S. F., Bedair A., Mansour F. R. Menthol-assisted homogenous liquid-liquid microextraction for HPLC/UV determination of favipiravir as an antiviral for COVID-19 in human plasma. Journal of Chromatography B. 2022;1189:123087. DOI: 10.1016/j.jchromb.2021.123087.</mixed-citation></citation-alternatives></ref><ref id="cit15"><label>15</label><citation-alternatives><mixed-citation xml:lang="ru">Комаров Т. Н., Карнакова П. К., Арчакова О. А., Щелгачева Д. С., Багаева Н. С., Шохин И. Е., Заславская К. Я., Белый П. А. Разработка и валидация методики определения фавипиравира в плазме крови человека методом ВЭЖХ-УФ. Разработка и регистрация лекарственных средств. 2022;11(3):220–229. DOI: 10.33380/2305-2066-2022-11-3-220-229.</mixed-citation><mixed-citation xml:lang="en">Komarov T. N., Karnakova P. K., Archakova O. A., Shchelgacheva D. S., Bagaeva N. S., Shohin I. E., Zaslavskaya K. Y., Bely P. A. Development and Validation of HPLC-UV Method for the Determination of Favipiravir in Human Plasma. Drug development &amp; registration. 2022;11(3):220–229. (In Russ.) DOI: 10.33380/2305-2066-2022-11-3-220-229.</mixed-citation></citation-alternatives></ref><ref id="cit16"><label>16</label><citation-alternatives><mixed-citation xml:lang="ru">Megahed S., Habib A., Hammad S., Kamal A. Chemometric Approach Based on Factorial and Box-Behnken Designs for Determination of Anti Coronavirus Drug; Favipiravir in Bulk and Spiked Human Plasma by Green HPLC Method. Turkish Journal of Analytical Chemistry. 2021;3(2):70–78. DOI: 10.51435/turkjac.963652.</mixed-citation><mixed-citation xml:lang="en">Megahed S., Habib A., Hammad S., Kamal A. Chemometric Approach Based on Factorial and Box-Behnken Designs for Determination of Anti Coronavirus Drug; Favipiravir in Bulk and Spiked Human Plasma by Green HPLC Method. Turkish Journal of Analytical Chemistry. 2021;3(2):70–78. DOI: 10.51435/turkjac.963652.</mixed-citation></citation-alternatives></ref><ref id="cit17"><label>17</label><citation-alternatives><mixed-citation xml:lang="ru">Morsy M. I., Nouman E. G., Abdallah Y. M., Zainelabdeen M. A., Darwish M. M., Hassan A. Y., Gouda A. S., Rezk M. R., Abdel-Megied A. M., Marzouk H. M. A Novel LC-MS/MS Method for Determination of the Potential Antiviral Candidate Favipiravir for the Emergency Treatment of SARS-CoV-2 Virus in Human Plasma: Application to a Bioequivalence Study in Egyptian Human Volunteers. Journal of Pharmaceutical and Biomedical Analysis. 2021;199:114057. DOI: 10.1016/j.jpba.2021.114057.</mixed-citation><mixed-citation xml:lang="en">Morsy M. I., Nouman E. G., Abdallah Y. M., Zainelabdeen M. A., Darwish M. M., Hassan A. Y., Gouda A. S., Rezk M. R., Abdel-Megied A. M., Marzouk H. M. A Novel LC-MS/MS Method for Determination of the Potential Antiviral Candidate Favipiravir for the Emergency Treatment of SARS-CoV-2 Virus in Human Plasma: Application to a Bioequivalence Study in Egyptian Human Volunteers. Journal of Pharmaceutical and Biomedical Analysis. 2021;199:114057. DOI: 10.1016/j.jpba.2021.114057.</mixed-citation></citation-alternatives></ref><ref id="cit18"><label>18</label><citation-alternatives><mixed-citation xml:lang="ru">Rezk M. R., Badr K. A., Abdel-Naby N. S., Ayyad M. M. A Novel, Rapid and Simple UPLC–MS/MS Method for Quantification of Favipiravir in Human Plasma: Application to a Bioequivalence Study. Biomedical Chromatography. 2021;35(7):e5098. DOI: 10.1002/bmc.5098.</mixed-citation><mixed-citation xml:lang="en">Rezk M. R., Badr K. A., Abdel-Naby N. S., Ayyad M. M. A Novel, Rapid and Simple UPLC–MS/MS Method for Quantification of Favipiravir in Human Plasma: Application to a Bioequivalence Study. Biomedical Chromatography. 2021;35(7):e5098. DOI: 10.1002/bmc.5098.</mixed-citation></citation-alternatives></ref></ref-list><fn-group><fn fn-type="conflict"><p>The authors declare that there are no conflicts of interest present.</p></fn></fn-group></back></article>
