Preclinical studies of antiviral activity of the RPH-137 fusion protein and molnupiravir against COVID-19

Finding effective and safe medicines to fight SARS-CoV-2 infection is an urgent task. RPH-137 is an original trap fusion protein against SARS-CoV-2 virus. It comprises the angiotensin-converting enzyme type 2 extracellular domain and the human IgG1 Fc fragment.The aim of the study was to carry out a preclinical evaluation of the efficacy of RPH-137 and molnupiravir against SARS-CoV-2 infection.Materials and methods: the authors analysed RPH-137 expressed in a stable CHO cell line and molnupiravir used as an active pharmaceutical ingredient. Drug-mediated inhibition of virus-induced cytotoxicity was assessed in Vero cell culture. In vivo efficacy assessments were performed in Syrian hamsters. The animals were infected intranasally with SARS-CoV-2 (PIK35 clinical isolate) in the dose of 5 log TCID50. The authors evaluated body weight measurements, lung–body weight ratios, and lung histopathology findings and determined viral RNA levels in oropharyngeal swabs by RT-PCR using the amplification cycle threshold (Ct). The statistical analyses involved one- and two-way ANOVA, Student's t-test, and Mann–Whitney test.Results: RPH-137 and molnupiravir inhibited the cytopathic effect of SARS-CoV-2 in Vero cells; the EC50 values of RPH-137 amounted to 4.69 μg/mL (21.3 nM) and 16.24 μg/mL (73.8 nM) for 50 TCID50 and 200 TCID50, respectively, whereas the EC50 values of molnupiravir were 0.63 μg/mL (1900 nM) for both doses. Intramuscular RPH-137 (30 and 80 mg/kg) had no effect on the infection process in Syrian hamsters. The comparison with the challenge control group showed that intraperitoneal RPH-137 (100 mg/kg) had statistically significant effects on a number of parameters, including a 27% reduction in inflammation and a 30% reduction in the total lesion area of the lungs by Day 7. Intragastric molnupiravir (300 mg/kg twice daily) significantly inhibited SARS-CoV-2 infection.Conclusions: both RPH-137 and molnupiravir inhibited the cytopathic effect of SARS-CoV-2 in Vero cells. In Syrian hamsters, molnupiravir demonstrated a more pronounced inhibition of SARS-CoV-2 infection than RPH-137. However, RPH-137 had statistically significant effects on a range of parameters. This offers additional perspectives for further research

Доклинические исследования противовирусной активности гибридного белка RPH-137 и молнупиравира в отношении COVID-19

Finding effective and safe medicines to fight SARS-CoV-2 infection is an urgent task. RPH-137 is an original trap fusion protein against SARS-CoV-2 virus. It comprises the angiotensin-converting enzyme type 2 extracellular domain and the human IgG1 Fc fragment.The aim of the study was to carry out a preclinical evaluation of the efficacy of RPH-137 and molnupiravir against SARS-CoV-2 infection.Materials and methods: the authors analysed RPH-137 expressed in a stable CHO cell line and molnupiravir used as an active pharmaceutical ingredient. Drug-mediated inhibition of virus-induced cytotoxicity was assessed in Vero cell culture. In vivo efficacy assessments were performed in Syrian hamsters. The animals were infected intranasally with SARS-CoV-2 (PIK35 clinical isolate) in the dose of 5 log TCID50. The authors evaluated body weight measurements, lung–body weight ratios, and lung histopathology findings and determined viral RNA levels in oropharyngeal swabs by RT-PCR using the amplification cycle threshold (Ct). The statistical analyses involved one- and two-way ANOVA, Student's t-test, and Mann–Whitney test.Results: RPH-137 and molnupiravir inhibited the cytopathic effect of SARS-CoV-2 in Vero cells; the EC50 values of RPH-137 amounted to 4.69 μg/mL (21.3 nM) and 16.24 μg/mL (73.8 nM) for 50 TCID50 and 200 TCID50, respectively, whereas the EC50 values of molnupiravir were 0.63 μg/mL (1900 nM) for both doses. Intramuscular RPH-137 (30 and 80 mg/kg) had no effect on the infection process in Syrian hamsters. The comparison with the challenge control group showed that intraperitoneal RPH-137 (100 mg/kg) had statistically significant effects on a number of parameters, including a 27% reduction in inflammation and a 30% reduction in the total lesion area of the lungs by Day 7. Intragastric molnupiravir (300 mg/kg twice daily) significantly inhibited SARS-CoV-2 infection.Conclusions: both RPH-137 and molnupiravir inhibited the cytopathic effect of SARS-CoV-2 in Vero cells. In Syrian hamsters, molnupiravir demonstrated a more pronounced inhibition of SARS-CoV-2 infection than RPH-137. However, RPH-137 had statistically significant effects on a range of parameters. This offers additional perspectives for further research.Поиск эффективных и безопасных лекарственных средств для борьбы с коронавирусной инфекцией, вызванной вирусом SARS-CoV-2, является актуальной задачей. RPH-137 – оригинальный гибридный белок-ловушка вируса SARS-CoV-2, состоящий из внеклеточного домена ангиотензинпревращающего фермента 2 типа и Fc-фрагмента IgG1 человека.Цель работы: доклиническая оценка эффективности RPH-137 и молнупиравира в отношении инфекции, вызванной SARS-CoV-2.Материалы и методы: RPH-137 получали в стабильной линии клеток китайского хомячка. В работе использовали субстанцию молнупиравира. Изучение ингибирования вирус-индуцированной цитотоксичности проводили в культуре клеток Vero. В исследовании эффективности in vivo сирийских хомячков заражали интраназально SARS-CoV-2 (вариант ПИК35) в дозе 5 lg ТЦД50. Оценивали массу тела, массовый коэффициент и гистологическую картину легких. В орофарингеальных мазках измеряли содержание вирусной РНК методом ОТ-ПЦР по показателю порогового цикла амплификации Ct. Статистическая обработка: однофакторный и двухфакторный дисперсионный анализ (ANOVA), t-тест Стьюдента, критерий Манна–Уитни.Результаты: RPH-137 и молнупиравир ингибировали цитопатическое действие вируса SARS-CoV-2 в культуре клеток Vero: для RPH-137 EC50=4,69 мкг/мл (21,3 нМ) и 16,24 мкг/мл (73,8 нМ) для доз 50 ТЦД50 и 200 ТЦД50 соответственно, для молнупиравира EC50=0,63 мкг/мл (1900 нМ) для обеих доз вируса. RPH-137 при внутримышечном введении в дозах 30 и 80 мг/кг не оказывал влияния на развитие инфекции у сирийских хомячков. RPH-137 при внутрибрюшинном введении в дозе 100 мг/кг показал статистически значимый эффект по ряду параметров по сравнению с животными контрольной группы (контроль заражения), в том числе вызывая снижение воспалительного процесса и общей площади поражения легких на 7 сут на 27 и 30% соответственно. Молнупиравир при пероральном введении в дозе 300 мг/кг 2 раза в сутки значимо подавлял развитие инфекции, вызванной SARS-CoV-2.Выводы: RPH-137 и  молнупиравир ингибируют цитопатическое действие вируса SARS-CoV-2 в культуре клеток Vero. У сирийских хомячков введение молнупиравира демонстрировало более выраженное подавление инфекции, вызванной SARS-CoV-2, по сравнению с RPH-137. Однако RPH-137 проявлял статистически значимое действие по ряду параметров, что открывает перспективы для его дальнейшего изучения.

A Comparative Parallel Study of Pharmacokinetics and Immunogenicity Following Single Intravenous Administration of Bevacizumab Biosimilar RPH-001 (Manufactured by R-Pharm Group, Russia) and Avastin® (Manufactured by F. Hoffmann-La Roche Ltd., Switzerland) in Healthy Male Volunteers

Introduction. Bevacizumab is a monoclonal IgG1 antibody that binds to and inhibits the biologic activity of human vascular endothelial growth factor (VEGF). Bevacizumab is used as a targeted monoor combination therapy for different solid tumors. Phase I clinical trial was performed to assess pharmacokinetics (PK) and immunogenicity of bevacizumab drugs. For this study 80 healthy male volunteers were recruited and randomized to either Avastin or RPH-001 group.Aim. To assess and compare pharmacokinetics and immunogenicity (safety) following single intravenous administration of Avastin® (manufactured by F. Hoffmann-La Roche Ltd., Switzerland) and bevacizumab biosimilar RPH-001 (manufactured by R-Pharm Group, Russia).Materials and methods. Bevacizumab quantitation and quasi-quantitative anti-bevacizumab antibodies detection in human blood serum were carried out using photometric ELISA. Two different methods were successfully validated.Results and discussion. Bevacizumab quantitation method was validated for selectivity and specificity, calibration curve, sensitivity, accuracy and precision, minimal required dilution, dilution linearity and stability. The anti-bevacizumab antibodies detection method was validated for cut-point (with normalization factor calculation), selectivity, sensitivity, precision, drug tolerance, dilution linearity, matrix effect (in case of serum hemolysis), and stability. The validated methods were successfully applied to pharmacokinetic and immunogenicity assessment of bevacizumab drugs.Conclusion. The results of the PK-study showed that test and reference bevacizumab drugs were equivalent. Immunogenicity study did not show any evidence of anti-bevacizumab antibodies in blood serum samples