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ABSTRACT Background Methods and Results Conclusions Hepatitis C virus genotype 5 (HCV‐GT‐5) is found mainly in South Africa. In our area in central France, the prevalence of HCV‐GT‐5 is 14%.Here we evaluated sustained virological response at week 12 post‐treatment (SVR12) in 147 HCV‐GT‐5 patients from 14 French university hospitals (2014–2021) treated with direct‐acting antivirals (DAA) in real‐life. Patients had mainly received sofosbuvir/ledipasvir ± ribavirin, sofosbuvir/velpatasvir, and glecaprevir/pibrentasvir. Overall SVR12 was 98% (144/147). Two patients experienced relapse: one was successfully retreated with the same DAAs (sofosbuvir/ledipasvir) plus ribavirin, and the other refused further DAA treatment. One patient with virological failure (sofosbuvir/velpatasvir) had received a second treatment (sofosbuvir/velpatasvir/voxilaprevir) and progressed to cure.HCV‐GT‐5 patients treated with a DAA regimen had a 99% SVR12 in intention‐to‐treat (including initial therapy and retreatment) and 100% SVR12 per protocol. Sofosbuvir/ledipasvir, sofosbuvir/velpatasvir, and glecaprevir/pibrentasvir show very good efficacy in real‐world HCV‐GT‐5 patients. [ABSTRACT FROM AUTHOR]

AbstractAmong the most prominent realizations of Morris J. Robins in the antiviral nucleoside chemistry are (i) the synthesis of 8-substituted (methyl-, amino-, bromo-, iodo) derivatives of acyclovir, (ii) xylotubercidin as an inhibitor of herpes simplex virus (HSV) infections, (iii) the anti-HIV activity of the 2’,3’-dideoxyriboside of 2,6-diaminopurine (ddDAPR) and the 3’-azido- and 3’-fluoro derivatives thereof (AzddDAPR and FddDAPR, respectively), (iv) the potentiating effect of ribavirin on the anti-HIV activity of 2’,3’-dideoxyinosine (ddI) and ddDAPR, (v) S-adenosylhomocysteine hydrolase (SAH) inhibitors principally active against vaccinia virus (VV) and vesicular stomatitis virus (VSV), and (vi) furo[2,3-d]pyrimidinone derivatives active against varicella-zoster virus (VZV). [ABSTRACT FROM AUTHOR]

In 2016, WHO designated Lassa fever a priority disease for epidemic preparedness as part of the WHO Blueprint for Action to Prevent Epidemics. One aspect of preparedness is to promote development of effective medical countermeasures (ie, diagnostics, therapeutics, and vaccines) against Lassa fever. Diagnostic testing for Lassa fever has important limitations and key advancements are needed to ensure rapid and accurate diagnosis. Additionally, the only treatment available for Lassa fever is ribavirin, but controversy exists regarding its effectiveness. Finally, no licensed vaccines are available for the prevention and control of Lassa fever. Ongoing epidemiological and behavioural studies are also crucial in providing actionable information for medical countermeasure development, use, and effectiveness in preventing and treating Lassa fever. This Personal View provides current research priorities for development of Lassa fever medical countermeasures based on literature published primarily in the last 5 years and consensus opinion of 20 subject matter experts with broad experience in public health or the development of diagnostics, therapeutics, and vaccines for Lassa fever. These priorities provide an important framework to ensure that Lassa fever medical countermeasures are developed and readily available for use in endemic and at-risk areas by the end of the decade. [ABSTRACT FROM AUTHOR]

Ribavirin and its analogues exhibit an in vitro antiproliferative effect in cancer cells. In this work, we studied the biological activities of a number of alkyl/aryloxymethyl derivatives of ribavirin's aglycon—1,2,4-triazole-3-carboxamide. Alkyl/arylxymethyl derivatives of 1,2,4-triazole-3-carboxamide with substitutions at the fifth or first position of the triazole ring, were synthesized and their antiproliferative and antimicrobial effects were assessed. For both series, the presence of an antiproliferative effect was investigated, and 1-alkyl/aryloxymethyl derivatives were shown an antimicrobial potential against a Gram-positive bacteria Micrococcus luteus and Gram-negative bacterium Pseudomonas aeruginosa. The obtained results showed that the n-decyloxymethyl derivatives induced leukemia cell death at low micromolar concentrations. We confirmed that n-decyloxymethyl derivatives of ribavirin inhibited the cell cycle progression and induced an accumulation of leukemia cells in the subG1-phase. The molecular docking results suggest that alkyl/aryloxymethyl derivatives may act by inhibiting translation initiation, due to interference with eIF4E assembly. The outcome results revealed that active derivatives (1- or 5-n-decyloxymethyl-1,2,4-triazole-3-carboxamides) can be considered as a lead compound for anticancer treatments. [ABSTRACT FROM AUTHOR]

Background The standard of care for Lassa fever is the use of ribavirin with supportive therapy. There is little information on the course of viremia and its relationship with clinical outcomes in patients treated with ribavirin. Methods We conducted a retrospective analysis of virologic and clinical parameters of 152 reverse transcription polymerase chain reaction–confirmed Lassa fever cases admitted and treated with ribavirin therapy. We describe the Lassa virus RNA kinetics in blood in relation to the clinical course of the patients. Results The overall mortality was 9%. The median duration (interquartile range [IQR]) of illness before admission was 8 (5–12) days. Median (IQR) Ct values on admission (t0) were lower among patients who died (21 [20–27]) than in those who survived (34 [30–37]; P <.01). The receiver operating characteristics curve of the association between outcome and Ct value at t0 had a high classification performance, with an AUC of 0.92 (95% CI, 0.86–0.98). The median time to viral clearance (IQR) was 10 (5–15) days. The viral load decreased steadily with the duration of treatment, and all survivors achieved viral clearance within 25 days of hospitalization. Conclusions Our study demonstrates that the Ct value on admission has prognostic value and Lassa fever patients treated with ribavirin typically clear the virus within 3–4 weeks of hospitalization. This kinetics has implications for the design of clinical case management and future clinical trial protocols. [ABSTRACT FROM AUTHOR]

Background Data on the presentation, management, and outcomes of Lassa fever (LF) in children are limited. Methods Description of the clinical and biological features, treatment, and outcomes of reverse transcriptase and polymerase chain reaction (RT-PCR)-confirmed LF in children aged under 15, enrolled in the LASsa fever clinical COurse and Prognostic factors in an Epidemic context (LASCOPE) prospective cohort study in Nigeria between April 2018 and February 2023. Results One hundred twenty-four children (aged under 12 months: 19; over 12 months: 105) were hospitalized with RT-PCR-confirmed LF. All received intravenous ribavirin. During follow-up, 99/124 (80%) had fever; 71/124 (57%) had digestive symptoms, vomiting (n  = 56/122, 46%) and abdominal pain (n  = 34/78 aged ≥5 years, 44%) more often than diarrhea (n  = 19/124, 15%); 17/124 (14%) had hemorrhagic signs; 44/112 (39%) had a hematocrit lower than 25%, of whom 32/44 (73%) received transfusions; 44/88 (50%) developed hypotension; 18/112 (16.1%) developed kidney disease improving global outcome (KDIGO) ≥2 acute kidney injury; 10/112 (8.9%) had KDIGO 3 acute kidney failure; 4/124 (3.2%) underwent renal replacement therapy. Seven children died, including 4 aged under 12 months (case fatality rate: under 12 months—22%, 95% confidence interval (CI): 7%–48%; over 12 months—2.9%, 95% CI: 0.7%–8.7%). In univariable analysis, age (P  = .003), impaired consciousness (P  = .026), and Lassa RT-PCR Ct value (P  = .006) were associated with Day 30 mortality. Conclusions The fatality rate for children over 12 months hospitalized with LF was lower than that previously reported for adults. Hypotension and acute kidney injury were the most frequent organ dysfunctions. Bleeding was relatively infrequent. Anemia and the need for transfusion were common, the relative contribution of ribavirin-induced hemolysis being unknown. [ABSTRACT FROM AUTHOR]

Outbreaks of human Nipah virus (NiV) cases have recently been reported in several countries. With a mortality rate of around 80% and no known therapy, there is an urgent need to test existing antivirals repurposed for it. Due to its central role in virus replication, the RNA-dependent RNA polymerase (RdRp) of NiV-L protein is a potential target for such antiviral therapies. In this study, Favipiravir, Remdesivir, Ribavirin, and their metabolites, including monophosphate (MP), diphosphate (DP), and triphosphate (TP), were virtually screened against RdRp. Using molecular dynamics (MD) simulations, lead hits from the docking study were examined for conformational changes. Additional analyses, including MM-PBSA, residual decomposition energy, and principal component analysis, were performed on the MD trajectory. Remdesivir-TP, Favipiravir-TP, and Ribavirin-TP exhibited the lowest binding energies of –7.8, −7.4, and −6.9 kcal/mol, respectively, and displayed an affinity for pocket 1, forming interactions with active site residues Asp726 and Asn727. During the 100 ns MD simulation, Remdesivir-TP demonstrated a more stable binding mode compared to Favipiravir-TP and Ribavirin-TP. The relative binding energies were −94.709 kJ/mol, −68.882 kJ/mol, and −46.98 kJ/mol for Remdesivir-TP, Favipiravir-TP, and Ribavirin-TP, respectively. This research anticipates Remdesivir-TP to be a potential candidate for an antiviral drug against NiV infection. [ABSTRACT FROM AUTHOR]

Background: This retrospective study focused on analyzing community-acquired respiratory virus (CARV) infections, in particular human parainfluenza virus (hPIV) after allogeneic stem cell transplant (allo-SCT) in adults recipients. It aimed to assess the impact of ribavirin treatment, clinical characteristics, and risk factors associated with lower respiratory tract disease (LRTD) progression and all-cause mortality. Patients and methods: The study included 230 allo-SCT recipients diagnosed with hPIV between December 2013 and June 2023. Risk factors for the development of LRTD, disease severity, and mortality were analyzed. Ribavirin treatment was administered at physician discretion in 61 out of 230 cases (27%). Results: Risk factors for LRTD progression in multivariate analysis were corticosteroids > 30 mg/day (Odds ratio (OR) 3.5, 95% Confidence Interval (C.I.) 1.3–9.4, p = 0.013), fever at the time of hPIV detection (OR 3.89, 95% C.I. 1.84–8.2, p < 0.001), and absolute lymphocyte count (ALC) < 0.2 × 109/L (OR 4.1, 95% C.I. 1.42–11.9, p = 0.009). In addition, the study found that ribavirin therapy significantly reduced progression to LRTD [OR 0.19, 95% C.I. 0.05–0.75, p = 0.018]. Co-infections (OR 5.7, 95% C.I. 1.4–23.5, p = 0.015) and ALC < 0.2 × 109/L (OR 17.7, 95% C.I. 3.6–87.1, p < 0.001) were independently associated with higher day + 100 after hPIV detection all-cause mortality. There were no significant differences in all-cause mortality and infectious mortality at day + 100 between the treated and untreated groups. Conclusion: ALC, corticosteroids, and fever increased the risk for progression to LRTD while ribavirin decreased the risk. However, mortality was associated with ALC and co-infections. This study supports further research of ribavirin therapy for hPIV in the allo-HSCT setting. [ABSTRACT FROM AUTHOR]

Background: Cell-penetrating peptides (CPPs) are effective for delivering therapeutic molecules with minimal toxicity. This study focuses on the use of penetratin, a well-characterized CPP, to deliver a DNA vector encoding short hairpin RNA (shRNA) targeting the respiratory syncytial virus (RSV) F gene into infected cells. RSV is known to cause severe lower respiratory infections in infants and poses significant risks to immunocompromised individuals and the elderly. We evaluated the antiviral efficacy of the penetratin-shRNA complex by comparing its ability to inhibit RSV replication and induce apoptosis with ribavirin treatment. Methods: Penetratin-shRNA complexes were prepared at different ratios and analyzed using gel retardation assays, dynamic light scattering, and zeta potential measurements. The complexes were tested in HEp-2 and A549 cells for transfection efficiency, cytotoxicity, viral load, and apoptosis using plaque assays, real-time reverse transcription-polymerase chain reaction (RT-PCR), DNA fragmentation, propidium iodide staining, and caspase 3/7 activation assays. Results: The gel shift assay determined that a 20:1 CPP-to-shRNA ratio was optimal for effective complexation, resulting in particles with a size of 164 nm and a zeta potential of 8.7 mV. Transfection efficiency in HEp-2 cells was highest at this ratio, reaching up to 93%. The penetratin-shRNA complex effectively silenced the RSV F gene, reduced viral titers, and decreased DNA fragmentation and apoptosis in infected cells. Conclusion: Penetratin effectively delivers shRNA targeting the RSV F gene, significantly reducing viral load and preventing apoptosis without toxicity. This approach surpasses Lipofectamine and shows potential for future therapeutic interventions, especially when combined with ribavirin, against RSV infection. [ABSTRACT FROM AUTHOR]

Amphiphilic copolymers (ACs) are versatile systems with self-assembling and aggregating properties, enabling the formation of nanomaterials (NMs) such as micelles, vesicles, nanocapsules, and nanogels. These materials have been extensively explored for the delivery of various drugs and active compounds, enhancing the solubility and permeation of poorly water-soluble drugs into skin tissue. This improvement facilitates the treatment of skin diseases, including chronic conditions like cancer, as well as infections caused by bacteria, fungi, and viruses. This review summarizes recent applications of ACs in skin treatment, with a particular focus on their use in anti-cancer drug therapy. It covers the synthesis, classification, and characterization of ACs using various experimental techniques. Additionally, it discusses recent research on different drug delivery pathways using ACs, including encapsulation efficiency, release behavior, characteristics, applications, and responses to various chemical and physical stimuli (both in vivo and in vitro). Furthermore, this review provides a comprehensive analysis of the effects of ACs NMs on several skin diseases, highlighting their potential as alternative treatments. [ABSTRACT FROM AUTHOR]

Recently, ribavirin has demonstrated effectiveness in treating glioblastoma through intranasal administration utilizing the nose-to-brain delivery route. Enhancing ribavirin's bioavailability can be achieved by utilizing intranasal stimuli-responsive systems that create a gel on the nasal mucosa. The research examined thermosensitive, pH-sensitive, and ion-selective polymers in various combinations and concentrations, chosen in line with the current Quality by Design (QbD) approach in pharmaceutical development. Following a thorough assessment of key parameters, the optimal composition of gellan gum at 0.5%, Poloxamer 124 at 2%, and purified water with ribavirin concentration at 100 mg/mL was formulated and subjected to in vivo testing. Through experiments on male rats, the nose-to-brain penetration mechanism of the active pharmaceutical ingredient (API) was elucidated, showcasing drug accumulation in the olfactory bulbs and brain. [ABSTRACT FROM AUTHOR]

Following the advent of direct-acting antivirals (DAAs), the treatment of hepatitis C virus (HCV) infection is now rarely challenging. However, data are still limited concerning DAA use in patients affected by glucose-6-phosphate dehydrogenase deficiency (G6PDd). Based on these considerations, the goal of this study was to evaluate the effectiveness and safety of DAAs in this subpopulation. A retrospective multicenter observational study (2015–2023) was conducted on all 2754 consecutive HCV-positive patients treated with first- and second-generation all-oral DAAs, and with a G6PDd diagnosis confirmed by quantitative testing (n = 38). At the treating clinician's discretion, an enhanced clinical and laboratory follow-up was performed, generally on a monthly basis both during treatment and up to six months after the end of it. Concerning hematochemical parameters, no significant differences were found between any considered time point. In all cases, no treatment-related adverse events were reported, and virologic response rates were as expected without G6PDd. In conclusion, in a large experience which, to the best of our knowledge, is unprecedented in the literature, the treatment of HCV hepatitis with nearly all available DAAs in patients with G6PDd as a comorbidity—a common occurrence in countries such as Italy—proved to be highly effective and safe. [ABSTRACT FROM AUTHOR]

Measles is a highly contagious but vaccine-preventable airborne-transmitted viral infection of which there has been a recent resurgence of cases worldwide over the past year, including in countries such as the UK, which had previously successfully achieved endemic measles elimination through vaccination programmes. Measles is typically a self-limiting illness, but can rarely cause severe, life-threatening disease, particularly when complicated by respiratory or neurological involvement. These severe complications are not typically seen in the absence of immunosuppression. We describe a rare case of severe measles with pneumonitis in an immunocompetent adult necessitating admission to an intensive care unit (ICU). [ABSTRACT FROM AUTHOR]

Triazoles serve as crucial intermediates in the production of ribavirin, a drug utilized for treating hepatitis C, respiratory syncytial virus (RSV) infections, and viral hemorrhagic fevers. In this study, we developed a rapid and straightforward method employing high-performance liquid chromatography with UV detection to determine triazoles used in these intermediates' synthesis. We compared several recently developed LC mixed-mode stationary phases with the classical C18 stationary phase. Using an Astra DM column with a multimodal stationary phase enabled rapid separation of all analytes within 3.2 min, surpassing the separation achieved with a C18 stationary phase. Our developed method demonstrated excellent linearity within a concentration range of 1 (2.5)–200 µg cm−3, with acceptable accuracy and precision levels within 1 and 5%, respectively. These results indicate that the optimized method is suitable for routine analysis of pertinent substances involved in the synthesis process, particularly when determining all ribavirin intermediates is necessary. [ABSTRACT FROM AUTHOR]

Ribavirin (1) esters 4–36 have been synthesized and tested for their anti-inflammatory and anti-viral properties against SARS-CoV-2. The impaired host immune response known as cytokine release syndrome is one of the major causes of COVID-19 infection-related death. The current study aimed to assess compounds 4–36 against viral infection in Vero cells (viral titration, cytopathic effects, anti-viral efficacy, and results of treatment points) and anti-inflammatory activity against cytokines (IL-2, GM-CSF, IL-6, TNF-α, IFN-γ and IL-1β) were quantified at the protein level by using ELISA, oxidative burst assay, nitric oxide inhibition assay, anti-proliferative activity. Cytotoxicity of compounds was also determined. Compound 13 showed promising results against anti-inflammatory activity (100.80%, IC50 = 0.40 ± 0.01 µM) and SARS-CoV-2 infection inhibition up to 80% (IC50 = 1.42 ± 0.28). Nonetheless, further investigation is necessary to enhance and synthesize long-acting Ribavirin esters-based anti-inflammatory and SARS-CoV-2 medications based on the identified patterns. [ABSTRACT FROM AUTHOR]

Background. Developing new effective plant protection methods against viruses is a vital task for seed potato production. The use of virus inhibitors (mainly synthetic ones) is the most common method in potato virus control. Products of natural origin might be a way to reduce the dependence on synthetic inhibitors. Among the former, extracts from seaweeds have high potential, producing a low or no negative impact on the environment or human health. Materials and methods. The materials of the research included potato cvs. ‘Poseidon’ and ‘Orion’ developed at the Federal Scientific Center of Agricultural Biotechnology of the Far East named after A.K. Chaika, the commercial antiviral product Ribavirin, and the sulfated polysaccharide – carrageenan – obtained from red algae at the G.B. Elyakov Pacific Institute of Bioorganic Chemistry. A highly sensitive PCR method was employed to detect viral infections in plant samples. Results. The efficacy of chemotherapy with Ribavirin (0.03%) was established at 79.8% against PVY, 77.0% against PLRV, 80.3% against PVM, and 84.5% against PVS. The most successfully eliminated viruses were PVY, PVM, and PVS. Carrageenan as an antiviral substance eliminated potato viruses at the following rates: PLRV in 74.7% of the explants, PVM in 70.2%, PVS in 69.2%, and PVY in 16.9%. Conclusion. Analyzing the antiviral activity of natural and synthetic virus inhibitors in the case study of carrageenan and Ribavirin demonstrated their high efficacy against potato viruses. Natural polysaccharides – carrageenans – were observed to have a significant antiviral effect, so their use in agricultural biotechnology might be promising for new experiments. Our approach successfully eliminated viruses in two new promising potato cultivars, ‘Poseidon’ and ‘Orion’, which were included in the system of virus-free seed production. These cultivars were submitted for patenting and official testing under the State Variety Trials.

Abstract Background Cell-penetrating peptides (CPPs) are effective for delivering therapeutic molecules with minimal toxicity. This study focuses on the use of penetratin, a well-characterized CPP, to deliver a DNA vector encoding short hairpin RNA (shRNA) targeting the respiratory syncytial virus (RSV) F gene into infected cells. RSV is known to cause severe lower respiratory infections in infants and poses significant risks to immunocompromised individuals and the elderly. We evaluated the antiviral efficacy of the penetratin-shRNA complex by comparing its ability to inhibit RSV replication and induce apoptosis with ribavirin treatment. Methods Penetratin-shRNA complexes were prepared at different ratios and analyzed using gel retardation assays, dynamic light scattering, and zeta potential measurements. The complexes were tested in HEp-2 and A549 cells for transfection efficiency, cytotoxicity, viral load, and apoptosis using plaque assays, real-time reverse transcription-polymerase chain reaction (RT-PCR), DNA fragmentation, propidium iodide staining, and caspase 3/7 activation assays. Results The gel shift assay determined that a 20:1 CPP-to-shRNA ratio was optimal for effective complexation, resulting in particles with a size of 164 nm and a zeta potential of 8.7 mV. Transfection efficiency in HEp-2 cells was highest at this ratio, reaching up to 93%. The penetratin-shRNA complex effectively silenced the RSV F gene, reduced viral titers, and decreased DNA fragmentation and apoptosis in infected cells. Conclusion Penetratin effectively delivers shRNA targeting the RSV F gene, significantly reducing viral load and preventing apoptosis without toxicity. This approach surpasses Lipofectamine and shows potential for future therapeutic interventions, especially when combined with ribavirin, against RSV infection. Graphical Abstract

Background and Aims: Systematic reviews and medical guidelines are widely used in clinical practice. However, these are often not up-to-date and focussed on the average patient. We therefore aimed to evaluate a guideline add-on, TherapySelector (TS), which is based on monthly updated data of all available high-quality studies, classified in specific patient profiles. Methods: We evaluated the TS for the treatment of hepatitis C (HCV) in an international cohort of patients treated with direct-acting antivirals between 2015 and 2020. The primary outcome was the number of patients receiving one of the two preferred treatment options of the HCV TS, based on the highest level of evidence, cure rate, absence of ribavirin-associated adverse effects, and treatment duration. Results: We enrolled 567 patients. The number of patients treated with one of the two preferred treatment options according to the HCV TS ranged between 27% (2015) and 60% (2020; p < 0.001). Most of the patients received a regimen with a longer treatment-duration (up to 34%) and/or addition of ribavirin (up to 14%). The effect on the expected cure-rate was minimal (1–6% higher) when the first preferred TherapySelector option was given compared to the actual treatment. Conclusions: Medical decision-making can be optimised by a guideline add-on; in HCV its use appears to minimise adverse effects and cost. The use of such an add-on might have a greater impact in diseases with suboptimal cure-rates, high costs or adverse effects, for which treatment options rely on specific patient characteristics. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to assess the overall treatment response of Genotype-3 Chronic HCV Pakistani Patients with or without cirrhosis to Ledipasvir plus Sofosbuvir combination. Method: In this observational study, HCV Genotype-3 patients were enrolled from Liver Center, DHQ Hospital, Faisalabad and divided into two groups, i.e., non-cirrhotic and compensated cirrhotic patients. The study spanned for a period of 24 months (November 2019 - November 2021) from the first enrollment to the last follow up. Non-cirrhotic patients received Ledipasvir/Sofosbuvir (LDV/SOF) 90/400mg for 12 weeks and cirrhotic patients received LDV/SOF with Ribavirin (RBV) for 12 weeks and without RBV for 24 weeks. The treatment efficacy in terms of sustained virological response (SVR12) was monitored 12 weeks post-treatment. The safety profile, and health-related quality of life (HRQoL) were monitored from baseline to follow-up visits. Results: Two hundred and ninety out of 309 (93.85%) non-cirrhotic and 31 out of 33 (93.94%) compensated cirrhotic patients achieved SVR-12. The safety profile of the non-cirrhotic and compensated cirrhotic patients was comparable throughout the study duration. Fatigue was the most commonly reported adverse event (AE) in non-cirrhotic and compensated cirrhotic patients, followed by headache, nausea, and fever. The HRQoL improved from baseline to follow-up visits among patients of both groups. Conclusion: It is concluded that LDV and SOF combination regimen is safe and effective for treating Genotype-3 HCV patients without cirrhosis/compensated cirrhosis, and also improves the patient’s HRQoL. [ABSTRACT FROM AUTHOR]

Ribavirin, an antiretroviral agent targeting the hepatitis C virus, causes male reproductive toxicity. This study investigated the mechanism of ribavirin transport at the blood–testis barrier (BTB). In vivo mouse integration plot analysis after intravenous administration revealed that the net influx clearance of [3H]ribavirin in the testis was 3.6-fold greater than that of [14C]D-mannitol, a paracellular transport marker, implying transcellular transport of ribavirin across the BTB. Moreover, [3H]ribavirin uptake by TM4 cells, mouse-derived Sertoli cells, was time- and concentration-dependent, with a K m value of 2.49 mM. S -[(4-nitrophenyl)methyl]-6-thioinosine, an inhibitor of Na+-independent equilibrative nucleoside transporters (ENTs), strongly inhibited the [3H]ribavirin uptake by TM4 cells at 100 µM. Compared to the uptake of [3H]adenosine, a typical endogenous nucleoside, [3H]ribavirin uptake was relatively similar to ENT2 transport. [3H]Ribavirin uptake was also observed in mouse ENT2-expressing Xenopus laevis oocytes, and gene silencing via the transfection of ENT2 small interfering RNA significantly reduced the [3H]ribavirin transport into TM4 cells by 13%. Taken together, these results suggest that ENT2 partially contributes to ribavirin transport at the BTB. [Display omitted] • Ribavirin, an anti-viral drug, undergoes the facilitative blood-to-testis transport in vivo. • Carrier-mediated processes contribute to the ribavirin transport at the BTB. • The characteristics of ribavirin transport at the BTB is different from ENT1-mediated adenosine transport. • ENT2 partially contributes to ribavirin transport at the BTB. [ABSTRACT FROM AUTHOR]

Background and Purpose: There is a need for effective anti‐COVID‐19 treatments, mainly for individuals at risk of severe disease such as the elderly and the immunosuppressed. Drug repositioning has proved effective in identifying drugs that can find a new application for the control of coronavirus disease, in particular COVID‐19. The purpose of the present study was to find synergistic antiviral combinations for COVID‐19 based on lethal mutagenesis. Experimental Approach: The effect of combinations of remdesivir and ribavirin on the infectivity of SARS‐CoV‐2 in cell culture has been tested. Viral populations were monitored by ultra‐deep sequencing, and the decrease of infectivity as a result of the treatment was measured. Key Results: Remdesivir and ribavirin exerted a synergistic inhibitory activity against SARS‐CoV‐2, quantified both by CompuSyn (Chou‐Talalay method) and Synergy Finder (ZIP‐score model). In serial passage experiments, virus extinction was readily achieved with remdesivir‐ribavirin combinations at concentrations well below their cytotoxic 50 value, but not with the drugs used individually. Deep sequencing of treated viral populations showed that remdesivir, ribavirin, and their combinations evoked significant increases of the number of viral mutations and haplotypes, as well as modification of diversity indices that characterize viral quasi‐species. Conclusion and Implications: SARS‐CoV‐2 extinction can be achieved by synergistic combination treatments based on lethal mutagenesis. In addition, the results offer prospects of triple drug treatments for effective SARS‐CoV‐2 suppression. [ABSTRACT FROM AUTHOR]

Ribavirin (RBV), which is extensively used to treat viral diseases such as COVID-19, is considered one of the major emerging contaminants due to its long-term existence and health risk in the aqueous environmental system. However, research on effective removal of RBV still remains insufficient. In this study, we investigated the RBV degradation kinetics and mechanism in UV/chlorine/Fe(II) process. The degradation rate constant kobs-RBV of RBV was 2.52 × 10−4 s−1 in UV/chlorine/Fe(II) process, which increased by 1.6 times and 1.3 times than that in chlorine alone and UV/chlorine process, respectively. Notably, trace amount Fe(II) promoted RBV degradation in UV/chlorine system through Fe2+/Fe3+ cycles, enhancing the yield of reactive species such as HO· and certain species reactive chlorine radicals (RCS). The contributions of HO· and RCS toward RBV degradation were 53.91% and 16.11%, respectively. Specifically, Cl·, ClO·, and Cl2·− were responsible for 8.59%, 2.69%, and 4.83% of RBV removal. The RBV degradation pathway indicated that the reactive species preferentially attacked the amide moiety of RBV, which cleaved the ether bond and the hydroxyl group. The toxicity evaluation of RBV degradation products elucidated that UV/chlorine/Fe(II) process was beneficial for RBV detoxification. [ABSTRACT FROM AUTHOR]

Introduction: Chronic hepatitis B (CHB) is a worldwide infectious disease caused by hepatitis B virus (HBV). Optimizing antiviral treatment strategies could improve the functional cure (FC) rate of patients with CHB. This study aims to systematically review the FC rate of the de novo combination of nucleos(t)ide analogs (NAs) and pegylated interferon a (PEG-IFNa) versus that of PEG-IFNa monotherapy for CHB. Methods: Databases were searched until 31 December 2023. Selected studies included randomized controlled trials on the de novo combination of NAs and PEG-IFNa versus PEG-IFNa monotherapy for 48 weeks in patients with CHB to achieve FC, which was defined as hepatitis B surface antigen (HBsAg) loss and/or HBsAg seroconversion. Meta-analysis was conducted in accordance with the efficacy at the end of treatment and different time points during follow-up. Results: A total of 10 studies, encompassing 2,339 patients in total, were included. Subgroup analysis was conducted in accordance with whether first-line NAs were used. It found no statistically significant difference between HBsAg loss and HBsAg seroconversion at the end of treatment. Serum HBV DNA <500 copies/mL significantly differed between the two groups at the end of treatment and did not significantly differ during follow-up. Meanwhile, HBsAg loss and HBsAg seroconversion showed statistically significant differences at 24 weeks of follow-up. By contrast, no statistically significant difference was found in HBsAg loss at 48 weeks of follow-up. Discussion: Without distinguishing the eligible preponderant population, the efficacy of the de novo combination of NAs and PEG-IFNa in treating patients with CHB was not superior to that of PEG-IFNa monotherapy. [ABSTRACT FROM AUTHOR]

Purpose: This research investigated the development of short hairpin RNA (shRNA) molecules designed to target specific regions of the human respiratory syncytial virus (HRSV) M and F genes. The study aimed to assess the therapeutic potential of these shRNAs and evaluate the effectiveness of Tat peptide-mediated delivery in enhancing their functionality. Methods: We acquired isolates from pediatric patients experiencing respiratory illness then cultured in HEp-2 cells. We constructed plasmids expressing shRNAs. Tat peptide as a facilitator for shRNA plasmid delivery was used. The cytotoxicity of ribavirin, shRNA constructs, and control agents was assessed using the MTT assay. The transfection efficiency of Tat peptide-mediated shRNA delivery with that of lipofectamine 3000TM were compared. Finally, real-time PCR was employed to quantify HRSV replication in the treated cells. Results: Tat peptide-mediated delivery of shRNA plasmids significantly suppressed the expression of the M and F genes of HRSV compared to lipofectamine 3000TM. This suppression was evident in both short-term experiments and scenarios involving stable shRNA expression. Furthermore, the combination of ribavirin with shRNA treatment resulted in a substantial reduction in viral load. Notably, the most pronounced antiviral effect was observed when both shRNAs were employed simultaneously. Conclusion: Our findings suggest that Tat peptide-mediated delivery of shRNA plasmids holds significant potential for achieving stable suppression of HRSV genes. This approach warrants further investigation as a potential gene therapy strategy for HRSV. By demonstrating promising results in vitro, this study highlights the need for future in vivo studies to comprehensively evaluate the therapeutic potential of this approach in a clinical setting. [ABSTRACT FROM AUTHOR]

1,2,4-Triazole derivatives have a wide range of biological activities. The most well-known drug that contains 1,2,4-triazole as part of its structure is the nucleoside analogue ribavirin, an antiviral drug. Finding new nucleosides based on 1,2,4-triazole is a topical task. The aim of this study was to synthesize ribosides and deoxyribosides of 1,2,4-triazole-3-thione derivatives and test their antiviral activity against herpes simplex viruses. Three compounds from a series of synthesized mono- and disubstituted 1,2,4-triazole-3-thione derivatives were found to be substrates for E. coli purine nucleoside phosphorylase. Of six prepared nucleosides, the riboside and deoxyriboside of 3-phenacylthio-1,2,4-triazole were obtained at good yields. The yields of the disubstituted 1,2,4-triazol-3-thiones were low due to the effect of bulky substituents at the C3 and C5 positions on the selectivity of enzymatic glycosylation for one particular nitrogen atom in the triazole ring. The results of cytotoxic and antiviral studies on acyclovir-sensitive wild-type strain HSV-1/L2(TK+) and acyclovir-resistant strain (HSV-1/L2/RACV) in Vero E6 cell culture showed that the incorporation of a thiobutyl substituent into the C5 position of 3-phenyl-1,2,4-triazole results in a significant increase in the cytotoxicity of the base and antiviral activity. The highest antiviral activity was observed in the 3-phenacylthio-1-(β-D-ribofuranosyl)-1,2,4-triazole and 5-butylthio-1-(2-deoxy-β-D-ribofuranosyl)-3-phenyl-1,2,4-triazole nucleosides, with their selectivity indexes being significantly higher than that of ribavirin. It was also found that with the increasing lipophilicity of the nucleosides, the activity and toxicity of the tested compounds increased. [ABSTRACT FROM AUTHOR]

Foot-and-mouth disease virus (FMDV) belongs to the Picornaviridae family and is an important pathogen affecting cloven-hoof livestock. However, neither effective vaccines covering all serotypes nor specific antivirals against FMDV infections are currently available. In this study, we employed virtual screening to screen for secondary metabolite terpenoids targeting the RNA-dependent RNA polymerase (RdRp), or 3Dpol, of FMDV. Subsequently, we identified the potential antiviral activity of the 32 top-ranked terpenoids, revealing that continentalic acid, dehydroabietic acid (abietic diterpenoids), brusatol, bruceine D, and bruceine E (tetracyclic triterpenoids) significantly reduced cytopathic effects and viral infection in the terpenoid-treated, FMDV-infected BHK-21 cells in a dose-dependent manner, with nanomolar to low micromolar levels. The FMDV minigenome assay demonstrated that brusatol and bruceine D, in particular, effectively blocked FMDV 3Dpol activity, exhibiting IC50 values in the range of 0.37–0.39 µM and surpassing the efficacy of the antiviral drug control, ribavirin. Continentalic acid and bruceine E exhibited moderate inhibition of FMDV 3Dpol. The predicted protein–ligand interaction confirmed that these potential terpenoids interacted with the main catalytic and bystander residues of FMDV 3Dpol. Additionally, brusatol and bruceine D exhibited additive effects when combined with ribavirin. In conclusion, terpenoids from natural resources show promise for the development of anti-FMD agents. [ABSTRACT FROM AUTHOR]

Glecaprevir/pibrentasvir (GLE/PIB) is an approved guideline‐recommended chronic hepatitis C virus infection treatment. GLE/PIB coadministration with ethinyl oestradiol (EE) is not recommended in current labels owing to a Phase 1 study observing Grade ≥2 alanine aminotransferase (ALT) elevation in 2 out of 12 healthy women cotreated for 11 days with GLE/PIB and oral contraceptive (OC) containing 35 μg/250 μg EE/norgestimate. No Grade ≥2 elevation was observed with low‐dose (20 μg) EE (n = 14). This Phase 1 study examined safety/tolerability of GLE/PIB coadministered with an OC containing low‐dose EE using a larger sample size and longer treatment duration. Healthy premenopausal women were treated with EE/levonorgestrel alone (20/100 μg, Cycles 1–2), followed by coadministration with GLE/PIB (300/120 mg; Cycles 3–4). A safety criterion of special interest was a confirmed Grade ≥2 ALT elevation (>3× upper normal limit). Adverse events (AEs) and study drugs concentrations were examined. Of 85 enrolled women, 72 initiated combined GLE/PIB + EE/levonorgestrel treatment, 66 completed the study and 19 discontinued prematurely (non‐safety reason, n = 16; AE [deemed unelated to GLE/PIB], n = 3). No participant met the safety criterion of special interest of confirmed Grade ≥2 ALT elevation. No serious/Grade ≥3 AEs were reported. Study drug concentrations were within the expected ranges. GLE/PIB in combination with an OC containing low‐dose EE was generally well tolerated with no confirmed Grade ≥2 ALT elevation and no evidence of drug‐induced liver injury. No pattern to the reported AEs and no new safety issues were identified. This was a Phase 1 study of healthy volunteers, not a registered clinical trial. [ABSTRACT FROM AUTHOR]

Background: Chikungunya virus (CHIKV), which causes chikungunya fever, is an arbovirus of public health concern with no approved antiviral therapies. A significant proportion of patients develop chronic arthritis after an infection. Zinc and magnesium salts help the immune system respond effectively against viral infections. This study explored the antiviral potential of zinc sulphate, zinc acetate, and magnesium sulphate against CHIKV infection. Methods: The highest non-toxic concentration of the salts (100 µM) was used to assess the prophylactic, virucidal, and therapeutic anti-CHIKV activities. Dosedependent antiviral effects were investigated to find out the 50% inhibitory concentration of the salts. Entry bypass assay was conducted to find out whether the salts affect virus entry or post entry stages. Virus output in all these experiments was estimated using a focus-forming unit assay, real-time RT-PCR, and immunofluorescence assay. Results: Different time- and temperature-dependent assays revealed the therapeutic antiviral activity of zinc and magnesium salts against CHIKV. A minimum exposure of 4 hours and treatment initiation within 1 to 2 hours of infection are required for inhibition of CHIKV. Entry assays revealed that zinc salt affected virus-entry. Entry bypass assays suggested that both salts affected postentry stages of CHIKV. In infected C57BL6 mice orally fed with zinc and magnesium salts, a reduction in viral RNA copy number was observed. Conclusion: The study results suggest zinc salts exert anti-CHIKV activity at entry and post entry stages of the virus life cycle, while magnesium salt affect CHIKV at post entry stages. Overall, the study highlights the significant antiviral potential of zinc sulphate, zinc acetate, and magnesium sulphate against CHIKV, which can be exploited in designing potential therapeutic strategies for early treatment of chikungunya patients, thereby reducing the virus-associated persistent arthritis. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV) is a long-neglected RNA virus and the major causative agent of acute viral hepatitis in humans. Recent data suggest that HEV has a very heterogeneous hypervariable region (HVR), which can tolerate major genomic rearrangements. In this study, we identify insertions of previously undescribed sequence snippets in serum samples of a ribavirin treatment failure patient. These insertions increase viral replication while not affecting sensitivity towards ribavirin in a subgenomic replicon assay. All insertions contain a predicted nuclear localization sequence and alanine scanning mutagenesis of lysine residues in the HVR influences viral replication. Sequential replacement of lysine residues additionally alters intracellular localization in a fluorescence dye-coupled construct. Furthermore, distinct sequence patterns outside the HVR are identified as viral determinants that recapitulate the enhancing effect. In conclusion, patient-derived insertions can increase HEV replication and synergistically acting viral determinants in and outside the HVR are described. These results will help to understand the underlying principles of viral adaptation by viral- and host-sequence snatching during the clinical course of infection. In this study, the authors identify genetic insertions in the population of hepatitis E virus analyzed in serum samples of a patient with ribavirin treatment failure. They show that these genomic rearrangements promote viral replication without affecting ribavirin sensitivity. [ABSTRACT FROM AUTHOR]

Carboxymethyl chitosan (CMCS) was modified by ribavirin (RTC), and then the ribavirin-modified carboxymethyl chitosan (RTC-CMCS) was blended with polyvinyl alcohol (PVA) by electrospinning technology to prepare nanofibers with high antibacterial, antiviral and good biocompatibility, which can be used in wound dressings and other fields. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV) can cause self-limiting acute and chronic hepatitis infections, particularly in immunocompromised individuals. In developing countries, HEV is mainly transmitted via drinking contaminated water, whereas zoonotic transmission dominates the route of infection in developed countries, including Japan. Pigs are an important reservoir for HEV infection. Wild boars, which share the same genus and species as domestic pigs, are also an HEV reservoir. During our nationwide study of HEV infection in wild boar populations in Japan, a genotype 6 (HEV-6) strain, wbJHG_23, was isolated in Hyogo Prefecture in 2023. The genomic length was 7244 nucleotides, excluding the poly(A) tract. The wbJHG_23 strain exhibited the highest nucleotide identity throughout its genome with two previously reported HEV-6 strains (80.3–80.9%). Conversely, it displayed lower similarity (73.3–78.1%) with the HEV-1–5, HEV-7, and HEV-8 strains, indicating that, although closely related, the wbJHG_23 strain differs significantly from the reported HEV-6 strains and might represent a novel subtype. The wbJHG_23 strain successfully infected the human-derived cancer cell lines, PLC/PRF/5 and A549 1-1H8 cells, suggesting that HEV-6 has the potential for zoonotic infection. An infectious cDNA clone was constructed using a reverse genetics system, and a cell culture system supporting the efficient propagation of the HEV-6 strain was established, providing important tools for further studies on this genotype. Using this cell culture system, we evaluated the sensitivity of the wbJHG_23 strain to ribavirin treatment. Its good response to this treatment suggested that it could be used to treat human infections caused by HEV-6. [ABSTRACT FROM AUTHOR]

Background: While the world is still facing the global pandemic COVID‐19, another zoonosis monkeypox (Mpox) has emerged posing a great threat to society. Insight into the pathogenesis, symptoms, and management strategies will aid in the development of potent therapeutics for the treatment of monkeypox virus infection. Objectives: To get insight into the current treatment and prevention strategies will aid in effectively coping with the disease. Methods: For obtaining information regarding the ongoing treatment and prevention strategies and the drugs under pipeline, we referred to Google Scholar, Pub Med, Pub Chem, and WHO official site. Results: There are a few drugs that came out to be effective for the treatment of Mpox. Tecovirimat acts by inhibiting viral replication and viral wrapping. Another drug is cidofovir, which hinders the activity of viral DNA polymerase but has the drawback of nephrotoxicity. To overcome this, a conjugate of cidofovir is being used—known as brincidofovir—which has a similar mechanism as cidofovir but lesser toxicity. Ribavirin acts via inhibiting inosine monophosphate dehydrogenase (IMPDPH) thus disrupting viral translation. It also interferes with helicase activity. Tiazofurin, Adenosine N1 oxide, and HPMPA have shown efficacy in in‐vitro studies by inhibiting IMPDH, DNA polymerase, and viral mRNA translation respectively. In‐silico studies have proven the effect of nilotinib, simeprevir, and dihydroergotamine for Mpox treatment. They have shown binding affinity for proteins required for the growth and release of MPXV. Vaccines have also been employed for the prevention of Mpox, which includes JYNNEOS, ACAM2000, and VIGIV. Conclusion: This review highlights the pathogenesis of the virus, disease manifestations, drugs, and vaccines that are being used and those under pipeline for the treatment and prevention of Mpox. [ABSTRACT FROM AUTHOR]

Hepatitis E virus is a single-strand, positive-sense RNA virus that can lead to chronic infection in immunocompromised patients. Virus–host recombinant variants (VHRVs) have been described in such patients. These variants integrate part of human genes into the polyproline-rich region that could introduce new post-translational modifications (PTMs), such as ubiquitination. The aim of this study was to characterize the replication capacity of different VHRVs, namely, RNF19A, ZNF787, KIF1B, EEF1A1, RNA18, RPS17, and RPL6. We used a plasmid encoding the Kernow strain, in which the fragment encoding the S17 insertion was deleted (Kernow p6 delS17) or replaced by fragments encoding the different insertions. The HEV RNA concentrations in the supernatants and the HepG2/C3A cell lysates were determined via RT-qPCR. The capsid protein ORF2 was immunostained. The effect of ribavirin was also assessed. The HEV RNA concentrations in the supernatants and the cell lysates were higher for the variants harboring the RNF19A, ZNF787, KIF1B, RPS17, and EEF1A1 insertions than for the Kernow p6 del S17, while it was not with RNA18 or RPL6 fragments. The number of ORF2 foci was higher for RNF19A, ZNF787, KIF1B, and RPS17 than for Kernow p6 del S17. VHRVs with replicative advantages were less sensitive to the antiviral effect of ribavirin. No difference in PTMs was found between VHRVs with a replicative advantage and those without. In conclusion, our study showed that insertions did not systematically confer a replicative advantage in vitro. Further studies are needed to determine the mechanisms underlying the differences in replicative capacity. IMPORTANCE Hepatitis E virus (HEV) is a major cause of viral hepatitis. HEV can lead to chronic infection in immunocompromised patients. Ribavirin treatment is currently used to treat such chronic infections. Recently, seven virus–host recombinant viruses were characterized in immunocompromised patients. These viruses have incorporated a portion of a human gene fragment into their genome. We studied the consequences of these insertions on the replication capacity. We found that these inserted fragments could enhance virus replication for five of the seven recombinant variants. We also showed that the recombinant variants with replicative advantages were less sensitive to ribavirin in vitro. Finally, we found that the mechanisms leading to such a replicative advantage do not seem to rely on the post-translational modifications introduced by the human gene fragment that could have modified the function of the viral protein. The mechanisms involved in improving the replication of such recombinant viruses remain to be explored. [ABSTRACT FROM AUTHOR]

Background: The risk of hepatocarcinoma in HCV cirrhotic patient responders after treatment with DAAs decrease, but HCC still occurs. A correlation between specific miRNAs and the development of hepatocarcinoma have been highlighted. Aim: To investigate miRNA expression in HCV-infected cirrhotic patients treated with DAAs, regarding whether or not they developed HCC at follow-up. Methods: A total of 73 outpatients with HCV-related cirrhosis treated with DAAs were enrolled, 28 of which had HCC. Samples were collected at the start and at the end of treatment. In the screening phase, 172 miRNAs were analyzed at baseline. Differentially expressed miRNAs were validated in the entire cohort. Results: In the validation phase, at baseline and in patients treated for 12 weeks, miR-28-5p was confirmed to be more highly expressed in the HCC group compared to the non-HCC group. In all of the patients treated for 12 weeks, at end of the treatment we found a significant downregulation in miR-132-3p, miR-133b-3p, miR-221-3p and miR-324-3p. In the HCC group, miR-28-5p was significantly downregulated after DAA therapy as well as in HCC patients treated for 24 weeks. Conclusion: In the HCC group, miR28-5p was differently expressed both at baseline and at the end of therapy with DAAs. This difference in expression should suggest its involvement in HCC development. [ABSTRACT FROM AUTHOR]

Among the common treatments for cancers, chemotherapy is widely used. One of the ways to evaluate the effectiveness of anti-cancer drugs is by checking the expression of tumor markers. Hence, this study aimed to evaluate the anti-cancer effects of the newly synthesized platinum ribavirin (Pt-Rb) compared to ribavirin (Rb) through biomarkers. In this study, cell lines were divided into four groups: groups A and B as healthy negative control group and untreated cancer group respectively. Group C and D were treated with, Rb and Pt-Rb, a novel anti-cancer drug, respectively. After evaluating LC50 for the drugs by MTT test, the expression of telomerase and Bcl-2 (B cell lymphoma-2) genes was evaluated using real-time PCR (RT-qPCR). The results showed a significant decrease in telomerase (0.020 ± 0.007) and Bcl-2(0.120 ± 0.005) gene expression in cancer cells treated with Pt-Rb (group D) compared to telomerase (0.040 ± 0.014) and Bcl-2(0.220 ± 0.014) treated with Rb (group C) and also between group D and telomerase (70.76 ± 0.330) and Bcl-2 (99.52 ± 0.670) in group B. The majority of the groups under investigation showed a significant difference (p < 0.05), suggesting that Pt-Rb had stronger anti-cancer effects than Rb and untreated cancer cells. Additionally, Pt-Rb treatment results demonstrated more increased apoptosis than Rb. Our results demonstrated that Pt-Rb is an effective medication in cancer treatment by lowering anti-apoptotic indicators. Therefore, this chemical has the potential to be an effective anti-cancer therapy, pending further research on animal models and then human volunteers. [ABSTRACT FROM AUTHOR]

The antiviral drug ribavirin is widely used and continuously released into the environment through various pathways, which will cause serious water pollution and virus resistance. However, only few works have examined ribavirin retention and transport groundwater environment. This study investigates the transport behavior of ribavirin in saturated quartz sand and limestone porous media, considering ionic strength (IS), ionic type and humic acid (HA), through column experiments and mathematical modeling. The findings reveal that, ribavirin exhibits strong mobility within saturated quartz sand media is less affected by different hydrochemical factors, posing a high risk of migration. In limestone porous media, the migration of ribavirin decreased. In comparison to Na+, the presence of Ca2+ causes the effluent recovery rate of ribavirin decreases. And as the IS of Ca2+ background solution increases, the effluent recovery rate of ribavirin also decreases. The presence of HA causes more ribavirin to flow out of the column, and its effect becomes more pronounced with increasing concentration. Furthermore, simulated precipitation scenarios, the ribavirin adsorbed on the of media surface is released again and transport with the water flow. These findings enhance our understanding about the environmental fate of ribavirin and facilitating ecological restoration efforts. [ABSTRACT FROM AUTHOR]

Background: Severe fever with thrombocytopenia syndrome (SFTS) is a zoonotic infectious disease caused by the severe fever with thrombocytopenia syndrome virus (SFTSV). Endemic in East Asia, SFTS is characterized by an exceptionally high mortality rate. Presently, there is no established treatment for SFTS, particularly for patients in critical condition. In this study, we collected and analyzed laboratory and clinical data from 92 critically ill patients with SFTS treated at Weihai Municipal Hospital between 2019 and 2022. We hope that our study will provide some hints for the treatment of critically ill patients with SFTS. Methods: A total of 92 critically ill patients with SFTS were included in this study. Of these patients, 45 received treatment with therapeutic plasma exchange (TPE) and ribavirin (referred to as the TPE group), while the remaining patients received only ribavirin (referred to as the non‐TPE group). Clinical and laboratory parameters were analyzed retrospectively. Results: The results showed significant improvements in multiple laboratory parameters following treatment with TPE and ribavirin, including white blood cell and neutrophil count, lactate dehydrogenase, creatine kinase isoenzyme‐MB, prothrombin time, activated partial thromboplastin time, D‐Dimer, serum sodium and copies of virus genomes. The combination of TPE with ribavirin demonstrated a significant reduction in mortality rates, with a mortality rate of 20.0% in the TPE group compared to 40.4% in the non‐TPE group (P = 0.033). Conclusions: Our findings suggest that critically ill patients with SFTS who received TPE and ribavirin experienced improvements in both clinical and laboratory parameters. These results indicate that TPE combined with ribavirin may represent a promising novel therapeutic approach for managing critically ill patients with SFTS. However, comparative studies of large sample size or randomized clinical trials are warranted to confirm the effectiveness of this combination therapy in the treatment of severe SFTS cases. [ABSTRACT FROM AUTHOR]