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<article 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" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="research-article" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Russian Journal of Infection and Immunity</journal-id><journal-title-group><journal-title xml:lang="en">Russian Journal of Infection and Immunity</journal-title><trans-title-group xml:lang="ru"><trans-title>Инфекция и иммунитет</trans-title></trans-title-group></journal-title-group><issn publication-format="print">2220-7619</issn><issn publication-format="electronic">2313-7398</issn><publisher><publisher-name xml:lang="en">SPb RAACI</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">8054</article-id><article-id pub-id-type="doi">10.15789/2220-7619-VNA-8054</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>ORIGINAL ARTICLES</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject></subj-group><subj-group subj-group-type="article-type"><subject>Research Article</subject></subj-group></article-categories><title-group><article-title xml:lang="en">Virus neutralizing antibodies in pseudovirus particle neutralization reaction as a bioanalytical part of a Salnavac® vaccine clinical trial</article-title><trans-title-group xml:lang="ru"><trans-title>Реакция нейтрализации псевдовирусных частиц вируснейтрализующими антителами как биоаналитическая часть клинического исследования вакцины Салнавак®</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-5519-8358</contrib-id><contrib-id contrib-id-type="spin">8769-9506</contrib-id><name-alternatives><name xml:lang="en"><surname>Zuev</surname><given-names>Evgeniy V.</given-names></name><name xml:lang="ru"><surname>Зуев</surname><given-names>Евгений Васильевич</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Lead Expert of the Group of Scientific and Medical Expertise and Clinical Development, Department of Scientific Expertise and Pharmacovigilance, Directorate for Clinical Trials and Pharmacovigilance</p></bio><bio xml:lang="ru"><p>ведущий эксперт группы научно-медицинской экспертизы и клинической разработки отдела научной экспертизы и фармаконадзора дирекции по клиническим исследованиям и фармаконадзору </p></bio><email>evzuev@generium.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-1179-3881</contrib-id><name-alternatives><name xml:lang="en"><surname>Markova</surname><given-names>Oksana Anatolievna</given-names></name><name xml:lang="ru"><surname>Маркова</surname><given-names>Оксана Анатольевна</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Head of the Department of Scientific Expertise and Pharmacovigilance, Directorate for Clinical Trials and Pharmacovigilance</p></bio><bio xml:lang="ru"><p>руководитель отдела научной экспертизы и фармаконадзора дирекции по клиническим исследованиям и фармаконадзору</p></bio><email>oamarkova@generium.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-4706-623X</contrib-id><name-alternatives><name xml:lang="en"><surname>Kulemzin</surname><given-names>Sergey V.</given-names></name><name xml:lang="ru"><surname>Кулемзин</surname><given-names>Сергей Викторович</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>PhD (Biology), Researcher</p></bio><bio xml:lang="ru"><p>к.б.н., научный сотрудник </p></bio><email>s.kulemzin@gmail.com</email><xref ref-type="aff" rid="aff2"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-2695-8869</contrib-id><name-alternatives><name xml:lang="en"><surname>Poteryaev</surname><given-names>Dmitry A.</given-names></name><name xml:lang="ru"><surname>Потеряев</surname><given-names>Дмитрий Александрович</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>PhD (Biology), Science Adviser</p></bio><bio xml:lang="ru"><p>к.б.н., cоветник по науке</p></bio><email>poteryaev@ibcgenerium.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-1430-8105</contrib-id><name-alternatives><name xml:lang="en"><surname>Litvinova</surname><given-names>Natalya A.</given-names></name><name xml:lang="ru"><surname>Литвинова</surname><given-names>Наталия Алексеевна</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>PhD (Biology), Head of Department of Molecular Diagnostics, Department of Pharmaceutical Analysis</p></bio><bio xml:lang="ru"><p>к.б.н., руководитель отдела молекулярной диагностики департамента фармацевтического анализа </p></bio><email>litvinova@ibcgenerium.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-1872-419X</contrib-id><name-alternatives><name xml:lang="en"><surname>Korotkevich</surname><given-names>Ilya A.</given-names></name><name xml:lang="ru"><surname>Короткевич</surname><given-names>Илья Александрович</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Biostatistician, Group of Biostatistics and Data Management, Department of Scientific Expertise and Pharmacovigilance, Directorate for Clinical Trials and Pharmacovigilance</p></bio><bio xml:lang="ru"><p>специалист по биостатистике группы биостатистики и управления данными отдела научной экспертизы и фармаконадзора дирекции по клиническим исследованиям и фармаконадзору</p></bio><email>iakorotkevich@generium.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-8658-7142</contrib-id><name-alternatives><name xml:lang="en"><surname>Grigiryeva</surname><given-names>Taisiya V.</given-names></name><name xml:lang="ru"><surname>Григорьева</surname><given-names>Таисия Викторовна</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Junior Clinical Research Project Manager, Medical Operations Department, Directorate for Clinical Trials and Pharmacovigilance</p></bio><bio xml:lang="ru"><p>младший менеджер проектов клинических исследований медицинского операционного отдела дирекции по клиническим исследованиям и фармаконадзору </p></bio><email>tvgrigorieva@generium.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-1314-894X</contrib-id><name-alternatives><name xml:lang="en"><surname>Khamitov</surname><given-names>Ravil A.</given-names></name><name xml:lang="ru"><surname>Хамитов</surname><given-names>Равиль Авгатович</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p> DSc (Medicine), Professor, Vice President of Research and Development</p></bio><bio xml:lang="ru"><p>д.м.н., профессор, вице-президент по исследованиям и разработкам</p></bio><email>khamitov@ibcgenerium.ru</email><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">JSC “GENERIUM”</institution></aff><aff><institution xml:lang="ru">АО "ГЕНЕРИУМ"</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff><institution xml:lang="en">LLC “IMGEN+”</institution></aff><aff><institution xml:lang="ru">ООО «ИМГЕН+»</institution></aff></aff-alternatives><pub-date date-type="preprint" iso-8601-date="2023-10-13" publication-format="electronic"><day>13</day><month>10</month><year>2023</year></pub-date><pub-date date-type="pub" iso-8601-date="2023-11-30" publication-format="electronic"><day>30</day><month>11</month><year>2023</year></pub-date><volume>13</volume><issue>5</issue><issue-title xml:lang="en"/><issue-title xml:lang="ru"/><fpage>853</fpage><lpage>863</lpage><history><date date-type="received" iso-8601-date="2023-03-21"><day>21</day><month>03</month><year>2023</year></date><date date-type="accepted" iso-8601-date="2023-10-05"><day>05</day><month>10</month><year>2023</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2023, Zuev E.V., Kulemzin S.V., Poteryaev D.A., Litvinova N.A., Markova O.A., Korotkevich I.A., Grigiryeva T.V., Kchamitov R.A.</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2023, Зуев Е.В., Кулемзин С.В., Потеряев Д.А., Литвинова Н.А., Маркова О.А., Короткевич И.А., Григорьева Т.В., Хамитов Р.А.</copyright-statement><copyright-year>2023</copyright-year><copyright-holder xml:lang="en">Zuev E.V., Kulemzin S.V., Poteryaev D.A., Litvinova N.A., Markova O.A., Korotkevich I.A., Grigiryeva T.V., Kchamitov R.A.</copyright-holder><copyright-holder xml:lang="ru">Зуев Е.В., Кулемзин С.В., Потеряев Д.А., Литвинова Н.А., Маркова О.А., Короткевич И.А., Григорьева Т.В., Хамитов Р.А.</copyright-holder><ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/"/><license><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://creativecommons.org/licenses/by/4.0</ali:license_ref></license></permissions><self-uri xlink:href="https://iimmun.ru/iimm/article/view/8054">https://iimmun.ru/iimm/article/view/8054</self-uri><abstract xml:lang="en"><p><italic>Introduction</italic>. The SARS-CoV-2 coronavirus pandemic has been a major challenge for all areas of medical science, causing a surge of new developments in various fields ranging from diagnostic techniques to therapeutic and preventive approaches. Intranasal vaccination is an innovative approach to immunization against SARS-CoV-2, which has attracted the attention of many drug developers. Dynamics of blood virus-neutralizing antibodies (VNAs) in recovered COVID-19 patients or vaccinated healthy volunteers is one of the objective parameters for assessing vaccine immunological efficacy, which requires high standards of bioanalytical techniques within the framework of clinical trials. Immunogenicity data on the two-component Salnavak<sup>®</sup> (intranasal) and Gam-COVID-Vac<sup>®</sup> (intramuscular) vaccination obtained in randomized double-blind multicenter phase 3 clinical trial interim analysis are presented. The objective of the study was to assess immunogenicity of intranasal and intramuscular vaccination against COVID-19 using a neutralization reaction with pseudoviral particles and HEK293T-hACE2 cell culture. <italic>Materials and methods.</italic> A total of 137 healthy volunteers with a baseline anti-RBD IgG level not exceeding 100 BAU/ml received immunization by a two-component (Ad26 and Ad5 based) intranasal or intramuscular vaccine administered on day 1 and day 21. Immunogenicity level based on VNA quantitative analysis using a neutralization reaction with pseudoviral particles and a HEK293T-hACE2 cell culture as well as to SARS-CoV-2 S-protein receptor-binding domain (anti-RBD) IgG antibodies on days 21 and 42 after administration of component I was assessed. <italic>Results.</italic> The geometric mean VNA titer against SARS-CoV-2 on day 42 was 238.34±3.93 and 616.94±3.73 in the Salnavac<sup>®</sup> and Gam-COVID-Vac<sup>®</sup> groups, respectively. Trial data shows sufficient immunological efficacy of both intramuscular and intranasal vaccines based on a high protection level at VNA titer of more than 100 while using the pseudoviral neutralization method. The geometric mean of the anti-RBD IgG level by day 42 was 131.22±3.91 and 782.03±3.04 in the Salnavac<sup>®</sup> and Gam-COVID-Vak<sup>®</sup> groups, respectively. A direct moderate correlation was shown between VHA and anti-RBD IgG. <italic>Conclusion</italic>. Neutralization reaction using pseudoviral particles was successfully validated and used to determine the VNA titer during clinical trial. Trial interim data revealed that intranasal vaccine Salnavac<sup>®</sup> vs intramuscular vaccine Gam-COVID-Vak<sup>®</sup> resulted in lower but sufficient stringency of humoral immunity.</p></abstract><trans-abstract xml:lang="ru"><p><italic>Введение</italic>. Пандемия коронавирусной инфекции, вызванной SARS-CoV-2, явилась серьезным испытанием для всех областей медицинской науки, вызвав всплеск новых разработок в различных сферах, начиная от диагностических методик, заканчивая терапевтическими и профилактическими подходами. Интраназальная вакцинация является инновационным подходом к иммунизации против SARS-CoV-2, к которому приковано внимание многих разработчиков препаратов. Одним из объективных параметров оценки иммунологической эффективности является изучение динамики накопления вируснейтрализующих антител (ВНА) в крови переболевших COVID-19 или получивших вакцинопрофилактику здоровых добровольцев, и требуют соблюдения высоких стандартов выполнения биоаналитической методики в рамках проведения клинических исследований. Представлены результаты промежуточного анализа данных иммуногенности, полученных в рамках рандомизированного двойного слепого многоцентрового клинического исследования 3 фазы двухкомпонентных препаратов Салнавак<sup>®</sup> (интраназально) и Гам-КОВИД-Вак<sup>®</sup> (внутримышечно). Целью исследования была оценка иммуногенности и безопасности интраназальной и внутримышечной форм комбинированной векторной вакцины против COVID-19 с помощью реакции нейтрализации с применением псевдовирусных частиц и культуры клеток НЕК293T-hAСЕ2. <italic>Материалы и методы.</italic> Всего 137 здоровых добровольцев с исходным уровнем анти-RBD IgG не выше 100 BAU/мл были иммунизированы двухкомпонентной (на основе Ad26 и Ad5) вакциной с интраназальным или внутримышечным способом введения в день 1 и день 21. Оценка иммуногенности проводилась на основании данных количественного определения ВНА с использованием реакции нейтрализации с применением псевдовирусных частиц и культуры клеток НЕК293T-hAСЕ2 и IgG-антител к рецептор-связывающему домену S-белка (анти-RBD) SARS-CoV-2 на 21 и 42 дни после введения компонента I. <italic>Результаты</italic>. Средний геометрический титр ВНА к SARS-CoV-2 в день 42 составил 238,34±3,93 и 616,94±3,73 в группах Салнавак<sup>®</sup> и Гам-КОВИД-Вак<sup>®</sup> соответственно. Учитывая данные о высоком уровне протективности при титре ВНА более 100 при применении метода псевдовирусной нейтрализации, полученные результаты свидетельствуют о достаточной иммунологической эффективности как внутримышечной, так и интраназальной вакцины. Среднее геометрическое значение уровня анти-RBD IgG в день 42 составило 131,22±3,91 и 782,03±3,04 в группах Салнавак<sup>®</sup> и Гам-КОВИД-Вак<sup>®</sup> соответственно. Показана прямая умеренная корреляция ВНА и анти-RBD IgG. <italic>Выводы</italic>. При проведении исследования для определения титра ВНА была успешно валидирована и использована реакция нейтрализации с применением псевдовирусных частиц. По итогам проведения промежуточного анализа данных была показана меньшая, чем у внутримышечного препарата, но достаточно высокая напряженность гуморального иммунитета после применения интраназальной вакцины Салнавак<sup>®</sup>.</p></trans-abstract><kwd-group xml:lang="en"><kwd>COVID-19</kwd><kwd>immunization</kwd><kwd>vaccine</kwd><kwd>coronavirus infection</kwd><kwd>immunogenicity</kwd><kwd>SARS-CoV-2</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>COVID-19</kwd><kwd>иммунизация</kwd><kwd>вакцина</kwd><kwd>коронавирусная инфекция</kwd><kwd>иммуногенность</kwd><kwd>SARS-CoV-2</kwd></kwd-group><funding-group/></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>СанПиН 3.3686-21 «Санитарно-эпидемиологические требования по профилактике инфекционных болезней». Утв. постановлением Главного государственного санитарного врача РФ от 28.01.2021 № 4. [3.3686-21. Sanitary rules for prevention of infectious diseases. 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