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<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">myrwd</journal-id><journal-title-group><journal-title xml:lang="ru">Реальная клиническая практика: данные и доказательства</journal-title><trans-title-group xml:lang="en"><trans-title>Real-World Data &amp; Evidence</trans-title></trans-title-group></journal-title-group><issn pub-type="epub">2782-3784</issn><publisher><publisher-name>Publishing House OKI</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.37489/2782-3784-myrwd-081</article-id><article-id custom-type="edn" pub-id-type="custom">ROYKWG</article-id><article-id custom-type="elpub" pub-id-type="custom">myrwd-112</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>КОГОРТНЫЕ ИССЛЕДОВАНИЯ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>COHORT STUDIES</subject></subj-group></article-categories><title-group><article-title>Фармакодинамический подход к оценке лейкопении, как маркёра эффективности терапии ингибиторами CDK4/6 у пациенток с HR+/HER2- метастатическим раком молочной железы: многоцентровое исследование реальной клинической практики</article-title><trans-title-group xml:lang="en"><trans-title>Pharmacodynamic approach to assessing leukopenia as a marker of treatment efficacy in CDK4/6 inhibitor therapy in patients with HR+/HER2- metastatic breast cancer: a multicenter real-world study</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-9413-367X</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Фатеева</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Fateeva</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Фатеева Анастасия Валерьевна — зав. центром амбулаторной онкологической помощи ГБУЗ Московской области «Химкинская клиническая больница»; аспирант кафедры общей и клинической фармакологии</p><p>Владивосток</p></bio><bio xml:lang="en"><p>Anastasia V. Fateeva — Head of the Center for Outpatient Oncological Care at the Khimki Clinical Hospital in the Moscow Region; postgraduate student at the Department of General and Clinical Pharmacology</p><p>Vladivostok</p></bio><email xlink:type="simple">ralise@bk.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/0000-0001-6126-1253</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Елисеева</surname><given-names>Е. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Eliseeva</surname><given-names>E. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Елисеева Екатерина Валерьевна — д. м. н., профессор, зав. кафедрой общей и клинической фармакологии</p><p>Владивосток</p></bio><bio xml:lang="en"><p>Ekaterina V. Yeliseeva — Dr. Sci. (Med.), Professor, Head of the Department of General and Clinical Pharmacology</p><p>Vladivostok</p></bio><email xlink:type="simple">yeliseeff23@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-6758-4800</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Вдовенко</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Vdovenko</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Вдовенко Алена Владимировна — к. м. н., ассистент кафедры онкологии и лучевой терапии с курсом ПО</p><p>Красноярск</p></bio><bio xml:lang="en"><p>Alyona V. Vdovenko — Cand. Sci. (Med.), Assistant Professor of Oncology and Radiation Therapy</p><p>Krasnoyarsk</p></bio><email xlink:type="simple">alena-vz@mail.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5862-1761</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Комиссарова</surname><given-names>В. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Komissarova</surname><given-names>V. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Комиссарова Валерия Алексеевна — зав. отделом скрининговых программ и профилактики; аспирант кафедры онкологии и лучевой терапии с курсом ПО</p><p>Красноярск</p></bio><bio xml:lang="en"><p>Valeria A. Komissarova — Head of the Department of Screening Programs and Prevention of Acute Respiratory Viral Infections; postgraduate student of the Department of Oncology and Radiation Therapy</p><p>Krasnoyarsk</p></bio><email xlink:type="simple">lera21734tkd@gmail.com</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-7210-3020</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Зуков</surname><given-names>Р. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Zukov</surname><given-names>R. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Зуков Руслан Александрович — д. м. н., профессор, главный врач; зав. кафедрой онкологии и лучевой терапии с курсом ПО</p><p>Красноярск</p></bio><bio xml:lang="en"><p>Ruslan A. Zukov — Dr. Sci. (Med.), Professor, Chief Physician; Head of the Department of Oncology and Radiation Therapy</p><p>Krasnoyarsk</p></bio><email xlink:type="simple">zukov_rus@mail.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-2494-4028</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Пономаренко</surname><given-names>Д. М.</given-names></name><name name-style="western" xml:lang="en"><surname>Ponomarenko</surname><given-names>D. M.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Пономаренко Дмитрий Михайлович — к. м. н., зав. химиотерапевтическим отделением № 1; ассистент кафедры онкологии</p><p>Иркутск</p></bio><bio xml:lang="en"><p>Dmitry M. Ponomarenko — Cand. Sci. (Med.), Head of the Chemotherapeutic Department No. 1; Assistant of the Department of Oncology of IGMAPO</p><p>Irkutsk</p></bio><email xlink:type="simple">ponomarenkodm@gmail.com</email><xref ref-type="aff" rid="aff-3"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5303-3012</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Россоха</surname><given-names>Е. И.</given-names></name><name name-style="western" xml:lang="en"><surname>Rossokha</surname><given-names>E. I.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Россоха Елена Ивановна — к. м. н., зав. отделением дневного стационара</p><p>Барнаул</p></bio><bio xml:lang="en"><p>Elena I. Rossokha — Cand. Sci. (Med.), Head of the Department of the day hospital</p><p>Barnaul</p></bio><email xlink:type="simple">rossokha_e@mail.ru</email><xref ref-type="aff" rid="aff-4"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-7171-8728</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Рябова</surname><given-names>Л. М.</given-names></name><name name-style="western" xml:lang="en"><surname>Ryabova</surname><given-names>L. M.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Рябова Лилия Михайловна — к. м. н., зам. директора по медицинской части</p><p>Томск</p></bio><bio xml:lang="en"><p>Lilia M. Ryabova — Cand. Sci. (Med.), Deputy Director for the Medical Department</p><p>Tomsk</p></bio><email xlink:type="simple">tomsk.ryabova@ldc.ru</email><xref ref-type="aff" rid="aff-5"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ФГБОУ ВО «Тихоокеанский государственный медицинский университет»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Pacific State Medical University</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>КГБУЗ «Красноярский краевой клинический онкологический диспансер им. А. И. Крыжановского»; ФГБОУ ВО «Красноярский государственный медицинский университет им. проф. В. Ф. Войно-Ясенецкого»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Krasnoyarsk Regional Clinical Oncological Dispensary named after A. I. Kryzhanovsky; Krasnoyarsk State Medical University named after prof. V. F. Voino-Yasenetsky</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru"><institution>ГБУЗ «Иркутский областной онкологический диспансер»; ФГБОУ ВО «Иркутский государственный медицинский университет»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Irkutsk Regional Oncological Dispensary;  Irkutsk State Medical University</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-4"><aff xml:lang="ru"><institution>КГБУЗ «Алтайский краевой онкологический диспансер»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Altai Regional Oncological Dispensary</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-5"><aff xml:lang="ru"><institution>ОП ООО Лечебно-диагностический центр Международного института биологических систем имени Сергея Березина</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Sergey Berezin Medical Institute Medical and Diagnostic Center</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2025</year></pub-date><pub-date pub-type="epub"><day>30</day><month>10</month><year>2025</year></pub-date><volume>5</volume><issue>3</issue><fpage>38</fpage><lpage>46</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Фатеева А.В., Елисеева Е.В., Вдовенко А.В., Комиссарова В.А., Зуков Р.А., Пономаренко Д.М., Россоха Е.И., Рябова Л.М., 2025</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="ru">Фатеева А.В., Елисеева Е.В., Вдовенко А.В., Комиссарова В.А., Зуков Р.А., Пономаренко Д.М., Россоха Е.И., Рябова Л.М.</copyright-holder><copyright-holder xml:lang="en">Fateeva A.V., Eliseeva E.V., Vdovenko A.V., Komissarova V.A., Zukov R.A., Ponomarenko D.M., Rossokha E.I., Ryabova L.M.</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.myrwd.ru/jour/article/view/112">https://www.myrwd.ru/jour/article/view/112</self-uri><abstract><sec><title>Актуальность</title><p>Актуальность. Внедрение ингибиторов CDK4/6 (палбоциклиб, рибоциклиб, абемациклиб) в клиническую практику существенно улучшило результаты лечения больных HR+/HER2-метастатическим раком молочной железы (мРМЖ). Однако отсутствие достоверных предикторов ответа на терапию ограничивает возможности персонализации лечения. Лейкопения, как наиболее частое гематологическое осложнение терапии CDK4/6-ингибиторами, может не только отражать степень миелосупрессии, но и служить косвенным индикатором фармакодинамического эффекта, связанного с подавлением пролиферации клеток костного мозга через механизм, аналогичный таргетному действию на опухоль. Несмотря на отдельные исследования, демонстрирующие потенциальную связь между степенью лейкопении и эффективностью терапии, данные реальной клинической практики остаются противоречивыми и недостаточно систематизированными.</p></sec><sec><title>Цель</title><p>Цель. Ретроспективное изучение в исследуемой когорте возможных предикторов эффективности CDk4/6 ингибиторов в условиях реальной клинической практики.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы. Проведён ретроспективный, многоцентровой анализ данных 170 больных HR+/HER2-мРМЖ, получавших терапию ингибиторами CDK4/6 (палбоциклиб или рибоциклиб) с 2019 по 2020 год в пяти онкологических центрах Сибири и Дальнего Востока. Пациентки были стратифицированы на две группы на основании максимальной степени токсичности по CTCAE v5.0: группа 1 (лейкопения G0–1, n=81) и группа 2 (лейкопения G≥2, n=89). Первичной конечной точкой была общая выживаемость (ОВ), вторичной — выживаемость без прогрессирования (ВБП).</p></sec><sec><title>Результаты</title><p>Результаты. Пациентки в группе 2 (лейкопения G≥2) продемонстрировали статистически значимое увеличение медианы ОВ по сравнению с группой 1 (лейкопения G0-1): 60,0 месяцев (95 % ДИ: 32,0–72,0) против 42,0 месяцев (95 % ДИ: 30,0–60,0), соответственно (отношение рисков [HR] 0,64; 95 % ДИ: 0,42–0,97; p=0,034). В анализе выживаемости без прогрессирования (ВБП) наблюдалась тенденция к улучшению в группе 2 (медиана 68,0 против 60,0 месяцев), однако она не достигла статистической значимости (p &gt;0,05).</p></sec><sec><title>Заключение</title><p>Заключение. В исследовании реальной клинической практики развитие лейкопении 2 степени и выше на фоне терапии ингибиторами CDK4/6 было ассоциировано с улучшением показателя общей выживаемости. Эти данные подтверждают, что степень миелосупрессии может служить ценным и легкодоступным предиктивным биомаркером эффективности лечения.</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Relevance</title><p>Relevance. The introduction of CDK4/6 inhibitors (palbociclib, ribociclib, and abemaciclib) into clinical practice has significantly improved the treatment outcomes of patients with metastatic HR+/HER2-breast cancer. However, the lack of reliable predictors of therapy response limits the possibilities of personalization of treatment. Leukopenia, the most common hematological complication of CDK4/6 inhibitor therapy, not only reflects the degree of myelosuppression but also serves as an indirect indicator of the pharmacodynamic effect associated with the suppression of bone marrow cell proliferation through a mechanism similar to the targeted effect on the tumor. Despite individual studies demonstrating a potential link between leukopenia degree and therapy effectiveness, data from actual clinical practice remain contradictory and insufficiently systematized.</p></sec><sec><title>Objective</title><p>Objective. This study retrospectively examined the possible predictors of CDk4/6 inhibitor effectiveness in clinical practice.</p></sec><sec><title>Materials and methods</title><p>Materials and methods. A retrospective, multicenter analysis of data from 170 HR+/HER2-breast cancer patients treated with CDK4/6 inhibitors (palbociclib or ribociclib) in five cancer centers in Siberia and the Far East from 2019 to 2020 was conducted. The patients were stratified into two groups based on the maximum degree of toxicity according to CTCAE v5.0: group 1 (leukopenia G0–1, n=81) and group 2 (leukopenia G≥2, n=89). The primary and secondary endpoints were overall survival (S) and progression-free survival (PFS).</p></sec><sec><title>Results</title><p>Results. Patients in group 2 (leukopenia G≥2) showed a statistically significant increase in median OS compared with group 1 (leukopenia G0-1): 60.0 months (95 % CI: 32.0–72.0) versus 42.0 months (95 % CI: 30.0–60.0), respectively (risk ratio [HR] 0.64; 95 % CI: 0.42–0.97; p=0.034). In the analysis of progression-free survival (PFS), an improvement trend was observed in group 2 (median 68.0 vs 60.0 months), but it did not reach statistical significance (p &gt;0.05).</p></sec><sec><title>Conclusion</title><p>Conclusion. In a real-world study, the development of grade 2 and higher leukopenia during CDK4/6 inhibitor therapy was associated with improved OS. These data confirm that the degree of myelosuppression can serve as a valuable and readily available predictive biomarker of treatment effectiveness.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>HR+/HER2- негативный рак молочной железы</kwd><kwd>CDK4/6-ингибиторы</kwd><kwd>PIK3CA</kwd><kwd>палбоциклиб</kwd><kwd>рибоциклиб</kwd><kwd>фармакодинамика</kwd><kwd>предикторы эффективности</kwd><kwd>лейкопения</kwd><kwd>нейтропения</kwd></kwd-group><kwd-group xml:lang="en"><kwd>HR+/HER2- negative breast cancer</kwd><kwd>CDK4/6 inhibitors</kwd><kwd>PIK3CA</kwd><kwd>palbociclib</kwd><kwd>ribociclib</kwd><kwd>pharmacodynamics</kwd><kwd>efficacy predictors</kwd><kwd>leukopenia</kwd><kwd>neutropenia</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">Sledge GW Jr, Toi M, Neven P, et al. 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