Overview of Antiviral Drug Therapy for COVID-19: Where Do We Stand?

Potent Cross-neutralizing Antibodies Reveal Vulnerabilities of Henipavirus Fusion Glycoprotein

Hendra and Nipah viruses (HNVs), zoonotic paramyxoviruses with >50% case fatality rates, cause fatal encephalitis and respiratory disease, yet lack approved therapies. Here, nine rhesus-derived monoclonal antibodies (mAbs) targeting the fusion glycoprotein (F) prefusion conformation are developed. Four mAbs exhibit first-rate cross-neutralization against HNVs, with two showing synergistic potency when combined with attachment glycoprotein (G)-specific mAbs. Single-dose administration of mAbs confers robust protection against lethal Nipah virus challenge in hamsters. Structural insights reveal that 8 of the 9 potent mAbs adopt a human IGHV4-59-like framework with protruding CDRH3 loops, forming pushpin-shaped paratopes that stabilize the prefusion F-trimer by occupying vulnerable interprotomer cavities. Systematic mutational profiling identifies 14 prefusion-locking residues within the F ectodomain, classified as i) structural linchpins governing fusogenicity or ii) immunodominant hotspots targeted by cross-neutralizing mAbs. This work delivers promising therapeutic candidates against HNVs and provides blueprints for the rational design of antibodies and vaccines targeting viral fusion machinery.

SARS-CoV-2 papain-like protease inhibits ISGylation of the viral nucleocapsid protein to evade host anti-viral immunity

A severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes mild-to-severe respiratory symptoms, including acute respiratory distress. Despite remarkable efforts to investigate the virological and pathological impacts of SARS-CoV-2, many of the characteristics of SARS-CoV-2 infection still remain unknown. The interferon-inducible ubiquitin-like protein ISG15 is covalently conjugated to several viral proteins to suppress their functions. It was reported that SARS-CoV-2 utilizes its papain-like protease (PLpro) to impede ISG15 conjugation, ISGylation. However, the role of ISGylation in SARS-CoV-2 infection remains unclear. We aimed to elucidate the role of ISGylation in SARS-CoV-2 replication. We observed that the SARS-CoV-2 nucleocapsid protein is a target protein for the HERC5 E3 ligase-mediated ISGylation in cultured cells. Site-directed mutagenesis reveals that the residue K374 within the C-terminal spacer B-N3 (SB/N3) domain is required for nucleocapsid-ISGylation, alongside conserved lysine residue in MERS-CoV (K372) and SARS-CoV (K375). We also observed that the nucleocapsid-ISGylation results in the disruption of nucleocapsid oligomerization, thereby inhibiting viral replication. Knockdown of ISG15 mRNA enhanced SARS-CoV-2 replication in the SARS-CoV-2 reporter replicon cells, while exogenous expression of ISGylation components partially hampered SARS-CoV-2 replication. Taken together, these results suggest that SARS-CoV-2 PLpro inhibits ISGylation of the nucleocapsid protein to promote viral replication by evading ISGylation-mediated disruption of the nucleocapsid oligomerization.IMPORTANCEISG15 is an interferon-inducible ubiquitin-like protein that is covalently conjugated to the viral protein via specific Lys residues and suppresses viral functions and viral propagation in many viruses. However, the role of ISGylation in SARS-CoV-2 infection remains largely unclear. Here, we demonstrated that the SARS-CoV-2 nucleocapsid protein is a target protein for the HERC5 E3 ligase-mediated ISGylation. We also found that the residue K374 within the C-terminal spacer B-N3 (SB/N3) domain is required for nucleocapsid-ISGylation. We obtained evidence suggesting that nucleocapsid-ISGylation results in the disruption of nucleocapsid-oligomerization, thereby suppressing SARS-CoV-2 replication. We discovered that SARS-CoV-2 papain-like protease inhibits ISG15 conjugation of nucleocapsid protein via its de-conjugating enzyme activity. The present study may contribute to gaining new insight into the roles of ISGylation-mediated anti-viral function in SARS-CoV-2 infection and may lead to the development of more potent and selective inhibitors targeted to SARS-CoV-2 nucleocapsid protein.

Nanostructured lipid carriers loaded with essential oils: a strategy against SARS-CoV-2

This work aimed to investigate the effectiveness of Lippia sidoides and Syzygium aromaticum essential oils (EOs) encapsulated in nanostructured lipid carriers (NLCs) as SARS-CoV-2 inhibitors through virucidal activity assessment. We developed anionic and cationic NLCs loaded with the EOs and assessed their physicochemical properties and SARS-CoV-2 virucidal activity, focusing on the effects of EO type and the NLCs composition. The NLCs exhibited particle sizes of 141.30 to 160.53 nm for anionic and 109.30 to 138.60 nm for cationic types, with PDIs between 0.16 and 0.25. High zeta potentials (>29.0 in modulus) indicated stable formulations. The NLCs effectively encapsulated the EOs, achieving encapsulation efficiencies between 84.6 to 100% w/w of marker compound. The EOs-loaded NLCs reduced the SARS-CoV-2 virion count, exceeding 2 logs over the control. NLCs loaded with Lippia sidoides and Syzygium aromaticum EOs represent an innovative strategy for combating SARS-CoV-2.

Navigating the waves in Colombia: a cohort study of inpatient care during four COVID-19 waves

INTRODUCTION

Understanding the intricate dynamics between different waves of the COVID-19 pandemic and the corresponding variations in clinical outcomes is essential for informed public health decision-making. Comprehensive insights into these fluctuations can guide resource allocation, healthcare policies, and the development of effective interventions. This study aimed to compare the characteristics and clinical outcomes of COVID-19 at peak transmission points by including all patients attended during the first four pandemic waves in a referral center in Colombia.

MATERIAL AND METHODS

In a prospective observational study of 2733 patients, clinical and demographic data were extracted from the Fundacion Valle de Lili's COVID-19 Registry, focusing on ICU admission, Invasive Mechanical Ventilation (IMV), length of hospital stay, and mortality.

RESULTS

Our analysis unveiled substantial shifts in patient care patterns. Notably, the proportion of patients receiving glucocorticoid therapy and experiencing secondary infections exhibited a pronounced decrease across waves (p < 0.001). Remarkably, there was a significant reduction in ICU admissions (62.83% vs. 51.23% vs. 58.23% vs. 46.70 %, p < 0.001), Invasive Mechanical Ventilation (IMV) usage (39.25% vs. 32.22% vs. 31.22% vs. 21.55 %, p < 0.001), and Length of Hospital Stay (LOS) (9 vs. 8 vs. 8 vs. 8 days, p < 0.001) over the successive waves. Surprisingly, hospital mortality remained stable at approximately 18‒20 % (p > 0.05). Notably, vaccination coverage with one or more doses surged from 0 % during the initial waves to 66.71 % in the fourth wave.

CONCLUSIONS

Our findings emphasize the critical importance of adapting healthcare strategies to the evolving dynamics of the pandemic. The reduction in ICU admissions, IMV utilization, and LOS, coupled with the rise in vaccination rates, underscores the adaptability of healthcare systems. Hospital mortality's persistence may warrant further exploration of treatment strategies. These insights can inform public health responses, helping policymakers allocate resources effectively and tailor interventions to specific phases of the pandemic.

A Narrative Overview of Coronavirus Infection: Clinical Signs and Symptoms, Viral Entry and Replication, Treatment Modalities, and Management

The global pandemic known as coronavirus disease (COVID-19) is causing morbidity and mortality on a daily basis. The severe acute respiratory syndrome coronavirus-2 (SARS-CoV- -2) virus has been around since December 2019 and has infected a high number of patients due to its idiopathic pathophysiology and rapid transmission. COVID-19 is now deemed a newly identified "syndrome" condition since it causes a variety of unpleasant symptoms and systemic side effects following the pandemic. Simultaneously, it always becomes potentially hazardous when new variants develop during evolution. Its random viral etiology prevents accurate and suitable therapy. Despite the fact that multiple preclinical and research studies have been conducted to combat this lethal virus, and various therapeutic targets have been identified, the precise course of therapy remains uncertain. However, just a few drugs have shown efficacy in treating this viral infection in its early stages. Currently, several medicines and vaccinations have been licensed following clinical trial research, and many countries are competing to find the most potent and effective immunizations against this highly transmissible illness. For this narrative review, we used PubMed, Google Scholar, and Scopus to obtain epidemiological data, pre-clinical and clinical trial outcomes, and recent therapeutic alternatives for treating COVID-19 viral infection. In this study, we discussed the disease's origin, etiology, transmission, current advances in clinical diagnostic technologies, different new therapeutic targets, pathophysiology, and future therapy options for this devastating virus. Finally, this review delves further into the hype surrounding the SARS-CoV-2 illness, as well as present and potential COVID-19 therapies.

Vaccination for seasonal flu, pneumococcal infection, and SARS-CoV-2 in patients with solid tumors: recommendations of the Associazione Italiana di Oncologia Medica (AIOM)

Patients with cancer have a well-known and higher risk of vaccine-preventable diseases (VPDs). VPDs may cause severe complications in this setting due to the immune system impairment, malnutrition and oncological treatments. Despite this evidence, vaccination rates are inadequate. The Italian Association of Medical Oncology (AIOM) has been involved in vaccination awareness since 2014. Based on a careful review of the available data about the immunogenicity, effectiveness and safety of flu, pneumococcal and anti-SARS-CoV-2 vaccines, we report the recommendations of the Associazione Italiana di Oncologia Medica about these vaccinations in adult patients with solid tumors. AIOM recommends comprehensive education on the issue of VPDs. We believe that a multidisciplinary care model may improve the vaccination coverage in immunocompromised patients. Continued surveillance, implementation of preventive practices and future well-designed immunological prospective studies are essential for a better management of our patients with cancer.

A Clinical Update on SARS-CoV-2: Pathology and Development of Potential Inhibitors

SARS-CoV-2 (severe acute respiratory syndrome) is highly infectious and causes severe acute respiratory distress syndrome (SARD), immune suppression, and multi-organ failure. For SARS-CoV-2, only supportive treatment options are available, such as oxygen supportive therapy, ventilator support, antibiotics for secondary infections, mineral and fluid treatment, and a significant subset of repurposed effective drugs. Viral targeted inhibitors are the most suitable molecules, such as ACE2 (angiotensin-converting enzyme-2) and RBD (receptor-binding domain) protein-based inhibitors, inhibitors of host proteases, inhibitors of viral proteases 3CLpro (3C-like proteinase) and PLpro (papain-like protease), inhibitors of replicative enzymes, inhibitors of viral attachment of SARS-CoV-2 to the ACE2 receptor and TMPRSS2 (transmembrane serine proteinase 2), inhibitors of HR1 (Heptad Repeat 1)-HR2 (Heptad Repeat 2) interaction at the S2 protein of the coronavirus, etc. Targeting the cathepsin L proteinase, peptide analogues, monoclonal antibodies, and protein chimaeras as RBD inhibitors interferes with the spike protein's ability to fuse to the membrane. Targeting the cathepsin L proteinase, peptide analogues, monoclonal antibodies, and protein chimaeras as RBD inhibitors interferes with the spike protein's ability to fuse to the membrane. Even with the tremendous progress made, creating effective drugs remains difficult. To develop COVID-19 treatment alternatives, clinical studies are examining a variety of therapy categories, including antibodies, antivirals, cell-based therapy, repurposed diagnostic medicines, and more. In this article, we discuss recent clinical updates on SARS-CoV-2 infection, clinical characteristics, diagnosis, immunopathology, the new emergence of variant, SARS-CoV-2, various approaches to drug development and treatment options. The development of therapies has been complicated by the global occurrence of many SARS-CoV-2 mutations. Discussion of this manuscript will provide new insight into drug pathophysiology and drug development.