Search Results (348)

Ebola virus (EBOV) causes severe disease in humans, with mortality as high as 90%. The small-molecule antiviral drug remdesivir (RDV) has demonstrated a survival benefit in EBOV-exposed rhesus macaques. Here, we characterize the efficacy of multiple intravenous RDV dosing regimens on survival of rhesus macaques 42 days after intramuscular EBOV exposure. Thirty rhesus macaques underwent surgical implantation of telemetry devices for the fine-scale monitoring of body temperature and activity, as well as central venous catheters, to enable treatment administration and blood collection. Treatment, consisting of a loading dose of RDV followed by once-daily maintenance doses for 11 days, was initiated 4 days after virus exposure when all animals were exhibiting disease signs consistent with incipient EBOV disease as well as quantifiable levels of EBOV RNA in plasma. In the RDV treatment groups receiving loading/maintenance doses of 5/2.5 mg/kg, 10/5 mg/kg, and 20/10 mg/kg, a total of 6 of 8 (75%), 7 of 8 (87.5%), and 5 of 7 (71.4%) animals survived, respectively. In the vehicle control group, one of seven animals (14.3%) survived. The improved survival rate compared to the control group was statistically significant only for the 10/5 mg/kg RDV treatment group. This treatment regimen also resulted in a significantly lower systemic viral load compared to the vehicle control after a single RDV treatment. All three RDV regimens produced a significantly lower systemic viral load after two treatments. For most animals, RDV treatment, regardless of dose, resulted in the amelioration of many of the clinical–pathological changes associated with EBOV disease in this model. Full article

Coronavirus disease 2019 (COVID-19) still causes death in elderly and immunocompromised individuals, for whom the sustainability of the vaccine response may be limited. Antiviral treatments, such as remdesivir or molnupiravir, have demonstrated limited clinical efficacy. Nirmatrelvir, an acute respiratory syndrome coronavirus 2 (SARS-CoV-2) major protease inhibitor, is clinically effective but has been associated with viral rebound and antiviral resistance. It is thus necessary to study novel and repurposed antivirals for the treatment of COVID-19. We previously demonstrated that daclatasvir (DCV), an inhibitor of the hepatitis C virus (HCV) NS5A protein, impairs SARS-CoV-2 replication by targeting viral RNA polymerase and exonuclease, but the doses of DCV used to inhibit the new coronavirus are greater than the standard human plasma exposure for hepatitis C. Because any potential use of DCV against SARS-CoV-2 would be shorter than that reported here and short-term toxicological studies on DCV show that higher doses are tolerable, we searched for doses of DCV that could protect transgenic mice expressing the human ACE2 receptor (K18-hACE-2) from lethal challenge with SARS-CoV-2. We found that a dose of 60 mg/kg/day provides this protection by reducing virus replication and virus-induced lung insult. This dose is tolerable in different animal models. Taken together, our data provide preclinical evidence that can support phase I clinical trials to confirm the safety, tolerability, and pharmacokinetics of new doses of daclatasvir for a short duration in humans to further advance this compound’s utility against COVID-19. Full article

Favipiravir (FVP) and remdesivir (RDV) have demonstrable antiviral activity against SARS-CoV-2. Here, the efficacy of FVP, RDV, and FVP with RDV (FVP + RDV) in combination was assessed in Syrian golden hamsters challenged with SARS-CoV- 2 (B.1.1.7) following intraperitoneal administration. At day 4 post infection, viral RNA and viral antigen expression were significantly lower in lungs for all three treatment groups compared to the sham treatment. Similarly, viral titres in the lungs were lower in all treatment groups compared to the sham treatment. The FVP + RDV combination was the only treatment group where viral RNA in nasal turbinate and lung, virus titres in lung, and viral antigen expression (lung) were all lower than those for the sham treatment group. Moreover, lower viral titre values were observed in the FVP + RDV group compared to other treatment groups, albeit only significantly lower in comparison to those in the RDV-only-treated group. Further assessment of the potential utility of FVP in combination with RDV may be warranted. Future studies should also consider whether the combination of these two drugs may reduce the speed at which drug resistance mutations are selected. Full article

The pathogen of COVID-19, SARS-CoV-2, has caused a severe global health crisis. So far, while COVID-19 has been suppressed, the continuous evolution of SARS-CoV-2 variants has reduced the effectiveness of vaccines such as mRNA-1273 and drugs such as Remdesivir. To uphold the effectiveness of vaccines and drugs prior to potential coronavirus outbreaks, it is necessary to explore the underlying mechanisms between biomolecules and nanodrugs. The experimental study reported that acrylamide fragments covalently attached to Cys145, the main protease enzyme (Mpro) of SARS-CoV-2, and occupied the substrate binding pocket, thereby disrupting protease dimerization. However, the potential mechanism linking them is unclear. The purpose of this work is to complement and validate experimental results, as well as to facilitate the study of novel antiviral drugs. Based on our experimental studies, we identified two acrylamide fragments and constructed corresponding protein-ligand complex models. Subsequently, we performed molecular dynamics (MD) simulations to unveil the crucial interaction mechanisms between these nanodrugs and SARS-CoV-2 Mpro. This approach allowed the capture of various binding conformations of the fragments on both monomeric and dimeric Mpro, revealing significant conformational dissociation between the catalytic and helix domains, which indicates the presence of allosteric targets. Notably, Compound 5 destabilizes Mpro dimerization and acts as an effective inhibitor by specifically targeting the active site, resulting in enhanced inhibitory effects. Consequently, these fragments can modulate Mpro’s conformational equilibrium among extended monomeric, compact, and dimeric forms, shedding light on the potential of these small molecules as novel inhibitors against coronaviruses. Overall, this research contributes to a broader understanding of drug development and fragment-based approaches in antiviral covalent therapeutics. Full article

Background/Objectives: COVID-19 led to a pandemic that has brought misery to millions of people but more so to those with pre-existing conditions. For this infection, several antiviral drugs were employed, including remdesivir (R) and Paxlovid (nirmatrelvir/ritonavir (NR)). Methods: The current study compared the effectiveness of remdesivir and Paxlovid treatment for COVID-19 patients with comorbid conditions. Data from a cohort of 151 adult patients with COVID-19 who also had associated comorbidities were used in this study. These patients were treated with antivirals according to local guidelines. The subjects included 78 case-patients assigned to group R and 73 to group NR. Results: In group NR, a considerable improvement in oxygen saturation was seen in the first 24 h of treatment (p = 0.010), but the levels were significantly higher from the second day of treatment (p < 0.001) in group R of patients. At the end of the 5 days of treatment, the oxygen saturation improved statistically significantly compared to the admission day, but only in the R group (95.11 ± 1.80; 91.76 ± 1.80; p < 0.001). Conclusions: Both drugs can be considered a breakthrough in the current treatment approach to the COVID-19 disease since they provide readily available options that can alleviate the severity of the disease and, hence, the prognosis of patients. That is why their effectiveness relies on the correct administration time and choosing the patient with suitable characteristics regarding the presence of comorbidities and the likelihood of the critical further development of the process. Full article

Cyclodextrin (CD) derivatives have gained significant attention in biomedical applications due to their remarkable biocompatibility, unique inclusion capabilities, and potential for functionalization. This review focuses on recent advancements in CD-based assemblies, specifically their role in improving drug delivery, emphasizing remdesivir (RMD). The review introduces CD materials and their versatile applications in self-assembly and supramolecular assembly. CD materials offer immense potential for designing drug delivery systems with enhanced activity. Their inherent inclusion capabilities enable the encapsulation of diverse therapeutic agents, including RMD, resulting in improved solubility, stability, and bioavailability. The recent advances in CD-based assemblies, focusing on their integration with RMD have been concentrated here. Various strategies for constructing these assemblies are discussed, including physical encapsulation, covalent conjugation, and surface functionalization techniques. Furthermore, exploring future directions in these fields has also been provided. Ongoing research efforts are directed toward developing novel CD derivatives with enhanced properties, such as increased encapsulation efficiency and improved release kinetics. Moreover, the integration of CD-based assemblies with advanced technologies such as nanomedicine and gene therapy holds tremendous promise for personalized medicine and precision therapeutics Full article

Herein, the pharmacokinetic profiles, binding interactions, and molecular properties of fluoroquinolone derivatives as prospective antiviral drugs are examined using a combination of docking, ADME, and DFT simulations. The effectiveness of the ligands is compared with the clinically tested and FDA-authorized medicine remdesivir. The findings demonstrated encouraging binding energies, indicating possible inhibitory effectiveness against SARS-CoV-2 M^pro. The fluoroquinolone derivatives also exhibit promising ADME characteristics, although compounds 5, 6, 9, 12–20 possess poor values, suggesting that oral administration may be possible. The potential of the selected compounds as SARS-CoV-2 M^pro inhibitors is thoroughly understood because of the integrated analysis of DFT, with compound 11 demonstrating the highest energy gap of 0.2604 eV of, docking with viral targets with docking scores of −7.9 to −5.9 kcal/mol, with compound 18 demonstrating the highest docking score, which is at the 13th position in energy difference in the DFT data. Their favorable electrical properties, robust binding interactions with viral targets, and attractive pharmacokinetic profiles boost their potential as prospective study subjects. These substances have the potential to be transformed into cutting-edge antiviral therapies that specifically target SARS-CoV-2 M^pro and related coronaviruses. Full article

Higher red blood cell distribution width (RDW) levels have gained attention in the prognostication of many chronic metabolic and malignant diseases, as well as coronavirus disease 2019 (COVID-19). We aimed to evaluate whether accounting for RDW might contribute to risk stratification when added to commonly used risk scoring systems in adult COVID-19 patients. We retrospectively analyzed a cohort of 3212 non-critical COVID-19 patients hospitalized in a tertiary-level institution from March 2020 to June 2021. Admission RDW values were considered normal if they were ≤14.5% in males or ≤16.1% in females. The Modified Early Warning Score (MEWS), International Severe Acute Respiratory and Emerging Infections Consortium Coronavirus Clinical Characterisation Consortium score (ISARIC 4C), and Veterans Health Administration COVID-19 (VACO) index were evaluated as prognostic scores. RDW exceeded the upper limit in 628 (19.6%) of the patients. When RDW was accounted for, risks of the predicted outcomes were considerably different within the same MEWS, 4C score, and VACO index levels. The same patterns applied equally to patients who started, and those who did not start, remdesivir before deterioration. RDW may be a useful tool for stratifying risk when considered on top of commonly used prognostic scores in non-critical COVID-19 patients. Full article

Background: The COVID-19 pandemic poses severe risks for immunocompromised patients, especially those with neutropenia due to chemotherapy. This study evaluates the safety and effectiveness of remdesivir use in COVID-19 patients with neutropenia. Methods: This retrospective study used the Chang Gung Research Database (CGRD) and extracted data from 98,763 patients with COVID-19 diagnosed between April 2021 and September 2022. The patients were divided into groups based on their remdesivir use and the presence of neutropenia. The adverse effects of remdesivir and their outcomes were analyzed after propensity score matching. Results: We compared common adverse effects of remdesivir in neutropenic patients before and after a 5-day regimen. A slight decrease in heart rate was observed but lacked clinical significance. There were no significant differences observed in hemoglobin, liver function tests, and blood glucose levels. After propensity score matching of COVID-19 patients with neutropenia according to gender, age, dexamethasone use, oxygen use, MASCC score, and WHO ordinal scale, no significant differences were found in length of stay, intubation rate, or ICU admission rate between the matched patients. Conclusions: Our study found remdesivir to be safe for COVID-19 patients with neutropenia, with no common adverse reactions observed. However, its effectiveness for these patients remains uncertain. Full article

Background: The extent of the SARS-CoV-2 short-term evolution under Remdesivir (RDV) exposure and whether it varies across different upper respiratory compartments are not fully understood. Methods: Patients hospitalized for COVID-19, with or without RDV therapy, were enrolled and completed up to three visits, in which they provided specimens from four respiratory compartments. Near full-length genome SARS-CoV-2 sequences were obtained from viral RNA, standard lineage and variant assignments were performed, and viral mutations in the RNA-dependent RNA polymerase (RdRp) region—the RDV target gene—were detected and compared between participants with and without RDV, across the four compartments, within participants across visits, and versus a larger sequence dataset. The statistical analysis used a generalized linear mixed-effects model. Results: A total of 139 sequences were obtained from 37 out of the 44 (84%) enrolled participants. The genotyping success varied across respiratory compartments, which ranged from 42% with oropharyngeal specimens to 67% with nasopharyngeal specimens and showed improvement with higher viral loads. No RdRp mutations known to be associated with RDV resistance were identified, and for 34 detected mutations at 32 amino acid positions that are not known as RDV-associated, there was no evidence of any associations with the RDV exposure, respiratory compartment, or time. At least 1 of these 34 mutations were detected in all participants, and some differed from the larger sequence dataset. Conclusions: This study highlighted the SARS-CoV-2 short-term genomic stability within hosts and across upper respiratory compartments, which suggests a lack of evolution of RDV resistance over time. This contributes to our understanding of SARS-CoV-2 genomic dynamics. Full article

Objective: This study aimed to assess changes in the morphology of the retina and cornea in patients treated and hospitalized during the acute active phase of SARS-CoV-2 infection. Methods: A total of 24 patients with symptomatic early COVID-19 disease and 38 healthy participants from a control group were enrolled in our study. Among them, 20 received oxygen therapy at flow rates ranging from 1–10 L, while four received high-flow intranasal oxygen therapy (HFNOT). Some patients were treated with other types of therapy, such as Remdesivir, COVID-19 convalescent plasma therapy, or Tocilizumab. In the study, we focused on the analysis of optical coherence tomography (OCT) images of the cornea and retina including corneal thickness, central retinal thickness, retinal nerve fiber layer (RNFL), and optic disc parameters. The measurements were acquired using Spectral-domain OCT REVO FC 130. Results: The analysis did not show significant changes between the examined ophthalmological parameters before and after therapy. Furthermore, there were no detected significant differences between the tested parameters of the retina and cornea in COVID-19-positive patients compared to the control group. Conclusions: No ophthalmological manifestations of COVID-19 disease were observed during the study. Taking into account the results of other publications, the lack of an unambiguous position on this topic requires further research. Full article

Human coronaviruses are a continuous threat to the human population and have limited antiviral treatments, and the recent COVID-19 pandemic sparked interest in finding new antiviral strategies, such as natural products, to combat emerging coronaviruses. Rapid efforts in the scientific community to identify effective antiviral agents for coronaviruses remain a focus to minimize mortalities and global setbacks. In this study, an essential oil derived from Myrtus communis L. (MEO) is effective against HCoV-229E and HCoV-OC43 virus infections in comparison to two FDA-approved drugs, Remdesivir and Nirmatrelvir. Gas-chromatography and mass spectrometry were used to identify the chemical composition of MEO. Slight antioxidant activity was observed in MEO, indicating a role in oxidative stress. A dose–response curve measuring the EC₅₀ indicates a high potency against HCoV-229E and HCoV-OC43 virus infections on Huh7.5 cells with low cytotoxicity using a PrestoBlue cell viability assay. Our findings demonstrate that MEO exhibits potent antiviral activity against HCoV-229E and HCoV-OC43 on Huh7.5 cells within a low-cytotoxicity range, but not on SARS-CoV-2. Artificial bacterial chromosome plasmids that expressed SARS-CoV-2 used for replicon—to determine viral replication and viral assembly/egress on HEK293T/17 cells—and virus-like particles on Huh7.5-AT cells—to determine viral entry and assembly/egress—showed no antiviral activity with MEO in comparison to Remdesivir. This study reveals the potential effectiveness of MEO as an alternative natural remedy to treat human coronaviruses and a potential antiviral agent for future coronavirus infections. Full article

The spread of COVID-19 has significantly increased research on antiviral drugs and measures such as case isolation and contact tracing. This study compared the effects of lopinavir/ritonavir and remdesivir on COVID-19 patients with a control group receiving no antiviral drugs. Patients confirmed to have a SARS-CoV-2 infection via real-time RT-PCR were divided into three groups: lopinavir/ritonavir, remdesivir, and control. We assessed the efficacy of these drugs in reducing viral load and viral shedding duration using real-time RT-PCR and Vero E6 cell cultures. Lopinavir/ritonavir led to no detectable infectious SARS-CoV-2, with a median viral clearance time of one day, whereas one remdesivir-treated case remained culture-positive until day 12. Lopinavir/ritonavir significantly reduced viral load compared to remdesivir and control groups (p = 0.0117 and p = 0.0478). No infectious virus was detected in the lopinavir/ritonavir group, and the non-infectious SARS-CoV-2 proportion remained constant at 90%, higher than in the remdesivir and control groups (p = 0.0097). There was a significant difference in culture positivity among the groups (p = 0.0234), particularly between the lopinavir/ritonavir and remdesivir groups (p = 0.0267). These findings suggest that lopinavir/ritonavir reduces viral load and shortens the viral shedding duration compared to remdesivir, despite not being an effective treatment option. Full article

Hyperinflammatory Coronavirus disease 2019 (COVID-19) and rapidly-progressive interstitial lung diseases (RP-ILD) secondary to inflammatory myopathies (IIM) present important similarities. These data support the use of anti-rheumatic drugs for the treatment of COVID-19. The aim of this study was to compare the efficacy of combining baricitinib and pulse steroids with the Standard of Care (SoC) for the treatment of critically ill COVID-19 patients. We retrospectively enrolled consecutive patients admitted to the Intensive Care Unit (ICU) with COVID-19-pneumonia. Patients treated with SoC (dexamethasone plus remdesivir) were compared to patients treated with baricitinib plus 6-methylprednisolone pulses (Rheuma-group). We enrolled 246 patients: 104/246 in the SoC and 142/246 in the Rheuma-group. All patients presented laboratory findings suggestive of hyperinflammatory response. Sixty-four patients (26.1%) died during ICU hospitalization. The mortality rate in the Rheuma-group was significantly lower than in the SoC-group (15.5 vs. 40.4%, p < 0.001). Compared to the SoC-group, patients in the Rheuma-group presented significantly lower inflammatory biomarker levels after one week of treatment. Higher ferritin levels after one week of treatment were strongly associated with mortality (p < 0.001). In this large real-life COVID-19 cohort, baricitinib and pulse steroids led to a significant reduction in mortality, paralleled by a prompt reduction in inflammatory biomarkers. Our experience supports the similarities between hyperinflammatory COVID-19 and the IIM-associated RP-ILD. Full article

The aim of this study was to investigate the effects of administrating Remdesivir at the acute COVID-19 phase on developing post-COVID symptoms in previously hospitalized COVID-19 survivors by controlling factors such as age, sex, body mass index, and vaccination status. A case-control study was performed. Hospitalized COVID-19 survivors who had received intravenous Remdesivir during the acute phase (n = 216) were matched by age, sex, body mass index, and vaccination status with survivors who did not receive antiviral treatment (n = 216). Participants were asked to self-report the presence of any post-COVID symptom (defined as a symptom that started no later than three months after infection) and whether the symptom persisted at the time of study (mean: 18.4, SD: 0.8 months). Anxiety levels (HADS-A), depressive symptoms (HADS-D), sleep quality (PSQI), and severity/disability (FIC) were also compared. The multivariate analysis revealed that administration of Remdesivir at the acute COVID-19 phase was a protective factor for long-term COVID development (OR0.401, 95%CI 0.256–0.628) and specifically for the following post-COVID symptoms: fatigue (OR0.399, 95%CI 0.270–0.590), pain (OR0.368, 95% CI 0.248–0.548), dyspnea at rest (OR0.580, 95%CI 0.361–0.933), concentration loss (OR0.368, 95%CI 0.151–0.901), memory loss (OR0.399, 95%CI 0.270–0.590), hair loss (OR0.103, 95%CI 0.052–0.207), and skin rashes (OR0.037, 95%CI 0.005–0.278). This study supports the potential protective role of intravenous administration of Remdesivir during the COVID-19 acute phase for long-lasting post-COVID symptoms in previously hospitalized COVID-19 survivors. Full article