[Results of a randomized double-blind multicenter clinical trial of the efficacy and safety of riamilovir in the treatment of COVID-19].

AIM: To evaluate the efficacy and safety of riamilovir in the treatment of COVID-19 in adults. MATERIALS AND METHODS: The study included 180 patients with a laboratory-confirmed diagnosis of COVID-19 which fully meet the criteria for inclusion, non-inclusion and exclusion, signed a voluntary informed consent to participate in a clinical trial. RESULTS: The efficacy, good tolerability and safety of the drug riamilovir in the treatment of COVID-19 have been established. CONCLUSION: As a result of a multicenter randomized double-blind clinical trial, the effectiveness of the drug riamilovir for therapeutic use in patients with COVID-19 according to the 1250 mg/day scheme (250 mg capsules 5 times per day) for 10 days was established. The drug riamilovir in a daily dose of 1250 mg for 10 days does not differ in safety from placebo.

[Results of a randomized double-blind multicenter clinical trial of the efficacy and safety of the drug riamilovir for the prevention of COVID-19].

AIM: Evaluation of the efficacy and safety of riamilovir as a drug for the prevention of coronavirus infection (COVID-19) in adults who have constant contact with COVID-19 patients as a result of living together. MATERIALS AND METHODS: The study included 750 adult participants living with patients with confirmed polymerase chain reaction method COVID-19, who had a negative polymerase chain reaction result for the SARS-CoV-2 virus at the initial level, met the criteria for inclusion, non-inclusion and exclusion, and signed a voluntary informed consent to participate in a clinical trial. RESULTS: The efficacy, good tolerability and safety of the drug riamilovir for the prevention of COVID-19 infection among people who have come into contact with COVID-19 patients in a family focus of infection have been established. CONCLUSION: As a result of a multicenter randomized double-blind clinical trial, the effectiveness of the drug riamilovir for the prevention of COVID-19 infection was established. It was shown that the relative risk of disease in the group taking riamilovir for prophylaxis was 88.96% lower than in the control group. Based on the results of a clinical trial, in October 2023 Ministry of Health of the Russian Federation approved the inclusion of a new indication (prophylaxis of COVID-19 infection) in the instructions for the medical use of the drug riamilovir (trade name - Triazavirin®).

[Efficacy and safety of bacterial lysate OM-85 in the treatment of uncomplicated acute respiratory infections: a double-blind, placebo-controlled, multicenter, randomized trial].

AIM: To evaluate the efficacy and safety of OM-85 in the treatment of uncomplicated acute respiratory infections (ARI) in adults. MATERIALS AND METHODS: A double-blind, placebo-controlled, multicenter, randomized trial included 556 patients (18-60 years old) with mild and moderate ARI and negative results of polymerase chain reaction analysis for SARS-CoV-2 RNA and rapid test for influenza A and B viruses. Patients were randomized into two groups: in the first group (n=278), patients received OM-85 (Broncho-munal®) one capsule 7 mg/day for 10 days, while the second group (n=278) was treated with placebo in the same regimen. The primary endpoint was the dynamics of the severity of symptoms over 3, 5, 7 and 10 days of treatment according to the 21-item Wisconsin Upper Respiratory Symptom Survey (WURSS-21), which was assessed by the area under the curve. Secondary efficacy criteria were the dynamics of the severity of symptoms according to the Common Cold Questionnaire (CCQ), the time to the resolution of symptoms according to WURSS-21 and CCQ, the proportion of patients with body temperature below 37°C on each day of treatment, frequency of the need for systemic antibacterial therapy. RESULTS: The superiority of OM-85 over placebo by primary endpoint was observed on the 5th, 7th and 10th days of treatment. OM-85 efficacy has also been proven by secondary criteria. OM-85 shortened the time until the symptoms of ARI resolved according to the WURSS-21 and CCQ, increased the proportion of patients with body temperature below 37°C by 2-9 days. The time needed to resolve the symptoms of disease in 20% of patients according to WURSS-21 was 7 and 9 days in patients taking OM-85 and placebo, respectively. Bacterial lysate increased the probability of complete disappearance of symptoms according to CCQ by 45.7% compared to placebo. The analysis of the frequency and severity of adverse events, laboratory tests, physical and instrumental examination results during treatment confirmed the good tolerability and safety of OM-85. CONCLUSION: The study confirmed the efficacy and safety of OM-85 in the complex treatment of ARI in adults.

[Frequency of drug resistance and immune escape mutations in the hepatitis B virus genome detected in pregnant women in the Republic of Guinea].

The aim of the work is to assess the prevalence of hepatitis B virus drug resistance mutations and immune escape mutations in pregnant women in the Republic of Guinea. MATERIALS AND METHODS: Blood plasma samples obtained from 480 pregnant women from different regions of the Republic of Guinea with laboratory-confirmed viral hepatitis B were studied. Nucleotide sequences for genotype identification and mutation detection were obtained using nested-PCR followed by Sanger sequencing, based on overlapping pairs of primers spanning the complete genome of the virus. RESULTS AND DISCUSSION: In the examined group, the viral genotype E was the most prevalent (92.92%) compared with subgenotypes A1 (1.67%), A3 (1.46%), D1 (0.63%), D2 (1.04%) and D3 (2.29%). Among the examined HBV-infected pregnant women, 188 (39.17%) had undetectable HBsAg. Drug resistance mutations were detected in 33 individuals, which amounted to 6.88%. The following mutations were found: S78T (27.27%), L80I (24.24%), S202I (15.15%), M204I/V (42.42%). The presence of polymorphic variants not described as drug resistant has also been shown in positions associated with the development of drug resistance to tenofovir, lamivudine, telbivudine and entecavir (L80F, S202I, M204R). When analyzing the MHR and the region of a determinant, mutations were detected in 318 (66.25%) of pregnant women. In 172 of them, which amounted to 54.09%, multiple mutations were found. The amino acid substitutions in 13 positions associated with HBsAg-negative hepatitis B and/or potentially affecting HBsAg antigenicity were identified. CONCLUSION: The high prevalence of immune escape and drug resistance mutations potentially associated with false-negative result of HBsAg screening, prophylaxis failure, and virological failure of therapy that has been identified among treatment naive pregnant women imposes a serious problem.

[Prevalence of viral hepatitis B markers among blood donors in the Republic of Guinea].

INTRODUCTION: The problem of transfusion safety in relation to parenteral viral hepatitis still remains relevant. Viral hepatitis B (HB) remains the most common viral infection transmitted through transfusion procedures. One of the natural phases of chronic hepatitis B (CHB) is occult hepatitis B infection (OBI), characterized by an undetectable HBsAg (regardless of the other serological markers content) in the presence of hepatitis B virus (HBV) DNA in the liver tissue and an extremely low, up to undetectable, level of viral load in the blood. In the Republic of Guinea, as in most countries on the continent, the prevention of HBV transmission through transfusion is still based on HBsAg serological testing of donors only. In this connection, OBI remains as a potential threat to blood transfusion safety. Detection of HBV DNA is a reliable preventive measure against transmission of the virus from donors with HBsAg-negative HBV infection, especially in highly endemic regions. In this regard, the study was conducted to substantiate recommendations for improving blood safety against the background of significant HBV prevalence in the Republic of Guinea.The aim of the work was the evaluation of serological and molecular markers of HBV infection in blood donors in the Republic of Guinea. MATERIAL AND METHODS: We examined 250 blood samples obtained from donors living in Conakry, Republic of Guinea. Samples were tested for the presence of serological (surface antigen, HBsAg; antibodies (ABs) to surface (anti-HBs IgG) and core (anti-HBc IgG) antigens) and molecular (DNA) markers of HBV infection. RESULTS AND DISCUSSION: The overall detection rate of hepatitis B markers was 83.2%; HBsAg was detected in 16.4% of all individuals. The high incidence of HBsAg in men (19.55%) compared to women (8.45%) was shown, the relative risk of HBV infection with the formation of HBsAg-positive chronic hepatitis B in males was also significantly higher. The prevalence of the HBV DNA in the study group was 30.4%, the OBI cases accounted for 15.6%. The prevalence of this form of the disease was shown in donors aged 30-49 years (24.78%), in the group of people younger than 30 years, the incidence was lower (8.73%), and at the age of over 50 years, OBI was not detected. Based on the phylogenetic analysis of 76 virus isolates, it was shown that genotype E prevails in the examined group (85.53%).Cases of pathogen DNA detection occurred in HBsAg-negative blood donors in the presence of anti-HBs IgG (n = 4), as well as in the simultaneous presence of ABs anti-HBs IgG and anti-HBc IgG (n = 7). The viral load exceeded 200 IU/ml in OBI samples. Escape mutations were detected by sequencing in each OBI sample, contributing to the virus escaping from diagnostic based on screening for HBsAg. CONCLUSION: Assessment of the prevalence viral hepatitis B markers in blood donors, determination of genotypes and clinically significant mutations of virus variants are necessary to ensure safe medical manipulations, control and prevention of the spread of this infectious agent.

[A new approach to etiotropic therapy ARVI in children].

AIM: Confirmation of the efficacy and safety of the drug riamilovir (Triazavirin®), 100 mg capsules, in children aged 12-17 years with the diagnosis of acute viral respiratory infection (ARVI). MATERIALS AND METHODS: The multicenter study included 269 patients diagnosed with acute viral respiratory infection (ICD-10 code: J00, J02, J02.9, J04, J04.0, J04.1, J04.2, J06, J06.0, J06.9) in the presence of clinical manifestations and confirmation of the etiology of the disease by laboratory tests (PCR method). Patients were included in the study after one of the patient's parents/adoptive parents and the patient signed an informed consent to participate in the study. The interval between the appearance of the first symptoms of the disease and the inclusion of the patient in the study did not exceed 36 hours. RESULTS: As a result of a clinical study, the efficacy and safety of treatment with riamilovir (Triazavirin®) in sick children aged 12-17 years with a diagnosis of ARVI was shown. A decrease in the duration of the disease was shown when using the drug riamilovir (Triazavirin®) compared with the control group. No serious adverse events were detected during the study. CONCLUSION: As a result of the conducted clinical study, the high efficacy, safety and good tolerability of the drug riamilovir in the treatment of children aged 12-17 years with a diagnosis of ARVI was established. It is recommended to use the drug riamilovir in clinical practice as an etiotropic therapy in children aged 12-17 years with a diagnosis of ARVI due to its high efficacy and safety.

[The detection of antibodies to HCV F protein with immune enzyme analysis using synthetic peptide.]

Alternative reading frame encoding a single protein known as protein F or core + 1 / ARFP is located in the core region of the hepatitis C virus (HCV) genome. The presence of antibodies to the F protein of HCV in the serum of patients with chronic hepatitis C indicates the expression of this protein in vivo. In this study, to determine antibodies to the F protein of HCV in serum samples the methodology of the enzyme immunoassay (ELISA) was developed using the synthetic peptide F10 corresponding to the antigenic determinant of the F protein of the HCV subtype 1b. The immunogenicity and immunochemical specificity of synthetic F10 peptide has been demonstrated in laboratory animals (mice).

[Clinical and morphological correlations in occult hepatitis B]. / Kliniko-morfologicheskie sopostavleniia pri okkul'tnom gepatite B.

Occult hepatitis B (ОHB) characterized by the absence of blood HBsAg attracts the attention of specialists of different profiles; however, its clinical morphological aspects have not been practically studied. AIM: to estimate the proportion of OHB in the structure of fatal outcomes in chronic viral hepatitis (CVH) and to characterize its clinical course and structural changes on autopsy materials. MATERIAL AND METHODS: A total of 455 autopsy cases of CVH were examined for its etiology in the S.P. Botkin Clinical Hospital of Infectious Diseases in 2014-2016. An in-depth prospective clinical analysis was made to investigate 28 cases of OHB in the stage of decompensated liver cirrhosis, which had subsequently culminated in death. The criteria of inclusion were history data and clinical symptoms of CVH in the detection of markers for hepatitis A, C, and D and HIV in serum HBcAb in the absence of HBsAg. HBsAbs were also determined. Along with the traditional morphological examination, immunohistochemistry (IHC) for HBsAg and HBcAg was carried out. RESULTS: There were 108 CVHB cases (23.7% of the total cases of CVH), including 77 OHB cases (71.3% of those of CVHB) while HBsAg was not determined. HBsAb-negative patients were more often observed to have clinical signs of jaundice (p<0.05) and skin itching (p<0.05). Dyspepsia and hemorrhagic manifestations prevailed in patients with HBsAb (more than 10 IU/l) (p<0.05). All the cases were found to have characteristic morphological signs of CVH, including intranuclear inclusions and nuclear polymorphism in 10.7% of deaths. There was an IHC-positive reaction to VHB antigens in 28.6% of the patients and a doubtful reaction in 25.0%. CONCLUSION: Serum НВсAb may serve as a diagnostic marker for HBV infection. Clinical and morphological correlations enabled the authors to state that CVHB was present in all cases in the absence of serum HBsAg in the patients.

Analysis of Populations of Memory T-Helper Cells Expressing CXCR3 and CCR6 Chemokine Receptors in Peripheral Blood of Patients with Chronic Viral Hepatitis C.

Flow cytometry was employed to examine the content of major populations of memory T helper cells and expression of chemokine receptors CXCR3 and CCR6 on their surface in peripheral blood drawn from virtually healthy people and the patients with chronic viral hepatitis C. The following combination of monoclonal antibodies had been used: CD62LFITC/CD45RA-PE/CD3-ECD/CCR6-PC7/CXCR3-APC/CD4-APC-Cy7. In comparison with control group, the patients with chronic hepatitis C had a smaller number of populations of naïve CD4(+) T cells and central memory CD4(+) T cells but a greater number of terminally differentiated effector memory CD4(+) T cells and effector memory CD4(+) T cells. No differences were revealed between CD4(+) T cell populations of both groups in expression of CXCR3 and CCR6 receptors.

Chemokine Receptors CXCR3 and CCR6 and Their Ligands in the Liver and Blood of Patients with Chronic Hepatitis C.

We performed a comprehensive analysis of CCR6 and CXCR3 chemokine receptors and their ligands CCL20/MIP-3α, CXCL9/MIG, CXCL10/IP-10, and CXCL11/ITAC in the liver and blood of patients with chronic hepatitis C at different stages of the disease. TaqMan PCR was used to determine mRNA gene expression of chemokines and their receptors in liver specimens, xMAP multiplex analysis was performed to estimate the concentration of chemokines in blood plasma, and fl ow cytofluorometry was used to evaluate CCR6 and CXCR3 expression on peripheral blood lymphocyte populations. In the liver of patients with hepatitis C, mRNA expression of CXCL10, CCR6, and CXCR3 genes increases with fibrosis progression in the liver tissue. In the plasma, concentrations of all studied chemokines increased depending on the stage of liver fibrosis, CCR6 and CXCR3 expression was changed in various lymphocyte populations. Thus, chemokines are involved in the immunopathogenesis and fibrogenesis in chronic viral hepatitis C. The results suggest using these chemokines in the diagnosis and prognosis of the disease.

[THE ROLE OF CYTOKINES AND CHEMOKINES IN LABORATORY DIAGNOSTIC OF CHRONIC VIRAL HEPATITIS C].

The chronic viral hepatitis C is widely prevalent disease with prolonged persistence of virus and obliterated clinical picture. The present techniques of diagnostic of degree of fibrosis of liver and prognosis of course of disease have particular shortcomings. Hence, search of safe low invasive methods based on blood biomarkers is an actual task. The cytokines/chemokines (mediators of chronic inflammation) directly involved into immunopathogenesis of chronic viral hepatitis C can act in the capacity of biomarkers. The study was carried out to comprehensively analyze content of cytokines/chemokines in peripheral blood of patients with chronic viral hepatitis C at various stages of disease and infected by different genotypes of virus of hepatitis C. The concentration of cytokines/chemokines was identified in blood plasma of patients with chronic viral hepatitis C (n = 73) and conditionally healthy donors (n =3 7): IFNα, IFNγ, IFNλ/IL28α, TNFα, CCL2/MCP-1, CCL3/MIP-lα, CCL4/MIP-lß, CCL5/RANTES, CCL8/MCP-2, CCL20/AIP-3α, CXCL9/MIG, CXCL10/P-10, CXCLII/ITAC. The multiplex analysis using technology xMAP was applied. The increasing of level of TNFα, CCL2/MCP-1, CCL4/ MIP-l, CCL8/ACP-2, CCL20/MIP-3α, CXCL9/MIG, CXCL10/IP-10, CXCL11/ITA C was established in blood plasma of patients with chronic viral hepatitis C as compared with control group. The levels of analyzed interferons IFNα, IFNγ, IFNλ/IL28α had no difference in studied groups. As far as chronic viral hepatitis C progresses and fibrosis of hepatic tissue develops the concentrations of TNFα, CCL2/MCP-1, CCL20/MIP-3α, CXCL9/MIG, CXCL10/IP-l0, CXCL11/ITAC increased significantly. The concentrations of chemokine CXCL11/IT4 C can be used as informative indicator for differentiating diagnostic of early stages of liver fibrosis. Depending on genotype of virus of hepatitis C, in patients with chronic viral hepatitis C change in content of CCL8/MCP-2 was established. Hence, detection in blood plasma of patients with chronic viral hepatitis C concentration of particular cytokines/chemokines using multiplex analysis technique permit analyzing additional information concerning degree of liver fibrosis, activity of process of damage of hepatic tissue under chronic viral hepatitis C that indicates indirectly on genotype of virus of hepatitis C.

[Sporadic and group imported cases of hepatitis E in St. Petersburg].

AIM: Carry out retrospective clinical-epidemiological analysis of sporadic and group cases of acute HE morbidity in St. Petersburg (2000 - 2012). MATERIALS AND METHODS; Medical histories of 11 patients with sporadic morbidity (9 males and 2 females, average age 36 +/- 18) and 13 patients involved in group HE morbidity were analyzed. Acute hepatitis E diagnosis was established based on common clinical-epidemiological criteria confirmed by results of biochemical study and data of objective examination. Hepatitis E etiological membership was confirmed by detection in patient blood sera of specific marker of infection--anti-HEV G and M classes with laboratory exclusion of hepatitis A, B and C. RESULTS: Study of epidemiological anamnesis of patients showed that 8 of them were migrants from countries with tropical and subtropical climate. 3 patients were residents of St. Petersburg. In the end of December 2011 and in January 2012 a group HE morbidity was registered among those who had arrived to study in St. Petersburg from India (Mumbai) in a group exceeding 200 individuals. Clinical characteristic of acute HE during sporadic and group morbidity is given. CONCLUSION: The presence of sporadic and group HE morbidity in St. Petersburg indicates the necessity to register these situation in organization of protection of the territory of Russia from endogenous HE.

[Features of population composition of peripheral blood CXCR3-positive lymphocytes in chronic viral hepatitis c patients].

AIM: Quantitative determination ofCXCR3+, CCR5+ and CCR6+ cells in major lymphocyte populations: T-helpers (Th), cytotoxic T-lymphocytes (CTL), natural killers (NK) and T-natural killer cells (TNK), B-lymphocytes in patients with chronic viral hepatitis C (CVHC). MATERIALS AND METHODS: Content of lymphocyte populations carrying chemokine receptor CXCR3 was studied, chemokine receptors CCR5 and CCR6 were evaluated on T-lymphocytes, in peripheral blood of 19 CVHC patients and 32 conditionally healthy donors. Cell populations were determined by flow cytofluorometry by using various combinations of monoclonal antibodies: for evaluation of Th and CTL (CD3/CD4/CD8/CXCR3/CCR5/CCR6); NK and TNK (CDl6/CD56/CD3/ CXCR3); B-cells (CD 19/CD45/CXCR3). RESULTS: In patients with CVHV compared with healthy donors a significant increase of quantity of CXCR3-positive Th was detected, however the content of CXCR3-positive CTL did not differ in the groups compared; CXCR3+ NK cell content was lower with equal content of CXCR3+ TNK. Analysis of quantity of CXCR3+ B-cells showed an increase of more than 3.5 times in CVHC patients. Significant differences in relative content of Th and CTL carrying CCR5 and CCR6 were not detected despite a non-significant increase of quantity of CCR5+ and CCR6+ Th. CONCLUSION: Content of major lymphocyte populations carrying chemokine receptor CXCR3 changed significantly compared with conditionally healthy donors in peripheral blood of CVHC patients. The increase of quantity of CXCR3-positive B-cells may be associated with infection of these cells by HCV or development of extra-liver manifestations of HVHC.

[Pathogenic aspects of influenza during the epidemics caused by A/H1N1v virus in 2009-2010 according autopsy data].

The paper is based upon the results of clinic-pathological and virological correlations in 29 lethal cases of influenza in Saint-Petersburg and Leningrad region during the epidemics 2009/2010. Immunohistochemical analysis of lungs, heart and brain using monoclonal sera to HA and HP proteins of influenza virus, virological and morphological analysis of experimental influenza in mice infected by A/WSN/33 (HIN1) and A/California/07/09 (H1N1) viruses had been carried out. In the majority of investigated strains was proved the amino acid mutation with replacement D222G. The replication of virus was demonstrated at the late stages of diseases, but the desquamation of respiratory epithelium and cytoproliferative weren't found out. Besides the "influenza cells", previously described by A. V Zinserling the cells with enlarge light nuclei were observed. Patients with influenza died from respiratory distress syndrome with minimal bacterial infection. We've established that H1N1 virus not only damages the cells of respiratory epithelium and alveolar macrophages but it can injure endothelium of different organs and neuroglia. The questions which have to be discussed are listed.

[Reamberin for pathogenetic therapy of acute and chronic viral diseases of the liver].

The study including 427 patients with acute and chronic viral hepatitis was designed to assess results of clinical and laboratory diagnostics of hepatic problems and the state of thiosulfide antioxidative system. It was shown that infusion of succinate-containing preparation reamberin (400 ml/day for 10 days) took less time to eliminate clinical manifestation of the disease (dispeptic and asthenovegetative syndromes) than conventional therapy. Simultaneously the levels of biochemical markers of hepatic cytolysis and cholestasis significantly decreased while serum antioxidative potential recovered. The normal size of the liver was achieved 3.4 times more frequently than in control. No side effects or adverse reactions other than listed in the instruction for use of reamberin occurred. The preparation had to be withdrawn only in one patient.

[Hepatoprotective activity of remaxol in patients with chronic hepatic disorders].

This milticentre randomized clinical study of the efficiency of remaxol infusion solution (hepatoprotective medicine for chronic liver dysfunction) included 494 patients with chronic hepatitis B and C. 294 of them staying in 7 clinics were given remaxol and 200 ones received placebo. Randomization was achieved by the envelope method. A detailed description of clinical and laboratory characteristics of the diseases is presented. Effects of remaxol vs placebo on the functional activity of affected liver are discussed. Results of laboratory and clinical analysis indicate that mechanism of remaxol action is based on hepatoprotective, antioxidative, and anticholestatic activities of the drug.

[Duration of viral RNA circulation in blood of patients with hepatitis A].

Duration of hepatitis A virus (HAV) RNA circulation in blood of patients with HA was assessed and compared with intensity of cytolytic syndrome. Detection of viral RNA was performed by RT-PCR method with specific primers to VP1/P2A region of HAV genome. 54 blood serum samples from 40 patients were prospectively studied on the presence of HAV RNA. The latterwas detected in 53.7% of serum samples. The greatest number of positive results of HAV RNA detection in blood of the patients with HA was obtained from 8th to 21st day of illness (77.4%). Prolonged viremia (42+/-9 days) was observed in more than 20% of the patients. The maximal time of HAV RNA daetection in blood serum amounted 74 days (period of follow-up). HAV RNA was present in almost all patients with AIAT activity higher than 500 U/l regardless of duration of illness.

[Interaction of hepatitis C virus with cytoplasmic membrane receptors].

The review presents the structure and incidence of these cell receptors and their role in the entry of hepatitis C virus. Some cell receptors, such as CD81, lipoprotein receptors, asialoglycoprotein receptors, DC-SIGN and L-SIGN, human scavenger receptors class B type I, cell surface heparin sulfate have been recently recognized as hepatitis C virus receptors.

[Structural and functional organization of hepatitis C virus genome].

The review gives recent data on the structure of hepatitis C virus genome. Linear RNA comprises one translated and two nontranslated regions: 5'UTR and 3'UTR. Translation of viral RNA gives rise to a single polyprotein precursor that contains structural and nonstructural regions. The structural region comprises one nucleocapsid core-protein and two envelope proteins known as E1 and E2. E2 protein includes two hypervariable regions: HVR1 and HVR2. The nonstructural region consists of 7 proteins: p7 (NS1), NS (metalloproteinase), NS (serine protease/ helicase), NS4A (co-factor protease, co-factor RNA-dependent RNA polymerase), and NS4B, NS5A, NS5B (RNA-dependent RNA polymerase). NS5A includes ISDR (interferon-sensitivity-determining region).