A Review of the Preclinical and Clinical Efficacy of Remdesivir, Hydroxychloroquine, and Lopinavir-Ritonavir Treatments against COVID-19

In December of 2019, an outbreak of a novel coronavirus flared in Wuhan, the capital city of the Hubei Province, China. The pathogen has been identified as a novel enveloped RNA beta-coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The virus SARS-CoV-2 is associated with a disease characterized by severe atypical pneumonia known as coronavirus 2019 (COVID-19). Typical symptoms of this disease include cough, fever, malaise, shortness of breath, gastrointestinal symptoms, anosmia, and, in severe cases, pneumonia.1 The high-risk group of COVID-19 patients includes people over the age of 60 years as well as people with existing cardiovascular disease and/or diabetes mellitus. Epidemiological investigations have suggested that the outbreak was associated with a live animal market in Wuhan. Within the first few months of the outbreak, cases were growing exponentially all over the world. The unabated spread of this deadly and highly infectious virus is a health emergency for all nations in the world and has led to the World Health Organization (WHO) declaring a pandemic on March 11, 2020. In this report, we consolidate and review the available clinically and preclinically relevant results emanating from in vitro animal models and clinical studies of drugs approved for emergency use as a treatment for COVID-19, including remdesivir, hydroxychloroquine, and lopinavir-ritonavir combinations. These compounds have been frequently touted as top candidates to treat COVID-19, but recent clinical reports suggest mixed outcomes on their efficacies within the current clinical protocol frameworks

Bisindolylmaleimide IX: a Novel Anti-SARS-CoV2 Agent Targeting Viral Main Protease 3CLpro Demonstrated by Virtual Screening Pipeline and In-Vitro Validation Assays

SARS-CoV-2, the virus that causes COVID-19 consists of several enzymes with essential functions within its proteome. Here, we focused on repurposing approved and investigational drugs/compounds. We targeted seven proteins with enzymatic activities known to be essential at different stages of the viral cycle including PLpro, 3CLpro, RdRP, Helicase, ExoN, NendoU, and 2′-O-MT. For virtual screening, energy minimization of a crystal structure of the modeled protein was carried out using the Protein Preparation Wizard (Schrodinger LLC 2020-1). Following active site selection based on data mining and COACH predictions, we performed a high-throughput virtual screen of drugs and investigational molecules (n = 5903). The screening was performed against viral targets using three sequential docking modes (i.e., HTVS, SP, and XP). Virtual screening identified ∼290 potential inhibitors based on the criteria of energy, docking parameters, ligand, and binding site strain and score. Drugs specific to each target protein were further analyzed for binding free energy perturbation by molecular mechanics (prime MM-GBSA) and pruning the hits to the top 32 candidates. The top lead from each target pool was further subjected to molecular dynamics simulation using the Desmond module. The resulting top eight hits were tested for their SARS-CoV-2 anti-viral activity in-vitro. Among these, a known inhibitor of protein kinase C isoforms, Bisindolylmaleimide IX (BIM IX), was found to be a potent inhibitor of SARS-CoV-2. Further, target validation through enzymatic assays confirmed 3CLpro to be the target. This is the first study that has showcased BIM IX as a COVID-19 inhibitor thereby validating our pipeline

Mycobacterium abscessus Glycopeptidolipid Prevents Respiratory Epithelial TLR2 Signaling as Measured by HβD2 Gene Expression and IL-8 Release

Mycobacterium abscessus has emerged as an important cause of lung infection, particularly in patients with bronchiectasis. Innate immune responses must be highly effective at preventing infection with M. abscessus because it is a ubiquitous environmental saprophyte and normal hosts are not commonly infected. M. abscessus exists as either a glycopeptidolipid (GPL) expressing variant (smooth phenotype) in which GPL masks underlying bioactive cell wall lipids, or as a variant lacking GPL which is immunostimulatory and invasive in macrophage infection models. Respiratory epithelium has been increasingly recognized as playing an important role in the innate immune response to pulmonary pathogens. Respiratory epithelial cells express toll-like receptors (TLRs) which mediate the innate immune response to pulmonary pathogens. Both interleukin-8 (IL-8) and human β-defensin 2 (HβD2) are expressed by respiratory epithelial cells in response to toll-like receptor 2 (TLR2) receptor stimulation. In this study, we demonstrate that respiratory epithelial cells respond to M. abscessus variants lacking GPL with expression of IL-8 and HβD2. Furthermore, we demonstrate that this interaction is mediated through TLR2. Conversely, M. abscessus expressing GPL does not stimulate expression of IL-8 or HβD2 by respiratory epithelial cells which is consistent with “masking” of underlying bioactive cell wall lipids by GPL. Because GPL-expressing smooth variants are the predominant phenotype existing in the environment, this provides an explanation whereby initial M. abscessus colonization of abnormal lung airways escapes detection by the innate immune system

Polymorphism of (Z)-3-Bromopropenoic acid: a high and low Z' pair

Two polymorphic forms of (Z)-3-Bromopropenoic acid are reported. Form I (monoclinic, P21/c) with Z' = 1 is obtained from a range of solvents while Form II (monoclinic, P21/n) with Z' = 4 can be prepared only from either benzene or toluene. Both forms are isolated at room temperature. The molecules in both polymorphs interact with one another through similar dominant hydrogen bonding motifs; however, the packing arrangement differs in the prevalence of weaker hydrogen bonds in the metastable Form II. Analysis of this high and low Z′ polymorphic pair using differential scanning calorimetry, grinding and slurry experiments, coupled with lattice energy calculations suggests that the low Z′ form I is the most stable under ambient conditions. 2D fingerprint plots derived from Hirshfeld surfaces highlight the more extensive hydrogen bonding in Form II while Form I is more densely packed. This polymorphic pair mat be a candidate for the role of solution pre-aggregation in the formation of high Z′ forms

Propulsion System for BWB Configurations in the Agile project

The focus of the present paper is the preliminary design of the propulsion and on-board systems and their integration for a Blended Wing Body (BWB) aircraft. The propulsion and on-board systems could deeply affect the aircraft performance and their weights. The aim is to consider all the main peculiarity of the BWB configuration affecting these systems. The innovative collaborative MDO process developed within the EU funded H2020 AGILE project is employed. Two configurations of BWB with different type of propulsion systems but with the same Top Level Aircraft Requirements (TLARs) are analyzed. The former has a conventional podded engine configuration while the latter is characterized by Distributed Propulsion System (DPS) and Boundary Layer Ingestion (BLI) system. Preliminary analyses about these two configurations are presented, showing the impacts of these alternative configurations on propulsion (fuel consumption, performance) and on-board systems (masses, power off-takes)

Comparative Study of Advanced Turboprop Aircraft with Wing and Rear Mounted Propulsion System in the Agile EU project

The present paper describes the comparison of two variantof the sameregionalturboprop aircraftusing the AGILE’s collaborative MDO process. The two turboprop aircraftareboth characterized by the same Top Level Aircraft Requirements,but with a different engine positions.The requirements are provided by the industrial partner (Leonardo –Aircraft Division) leading to twoaircraft configurationswith wing and rear mounted propulsion system.A complete aircraft preliminary design is carried out to understand the effect of engine position considering all the main design disciplines. 13 engine design cases related to differentflight conditions and engine ratings are considered to select engine cycle and size. Baseline engine size isdefined by high shaft power requirements at max continuous conditionsand by power and thrustrequirementat other design cases. Improvement of cruise installed SFC of baseline engine by 6-7% is shownto reach given preliminary requirement on cruise SFC level.The results ofthe twoaircraft are obtained and compared, showingthatthe rear mounted engine configuration can reach higher cruise speeds, despiteslight incrementsof on-board systems weight and required mission fuel

Polymorphism and Phase Transformation Behavior of Solid Forms of 4-Amino-3,5-dinitrobenzamide

We report the preparation, analysis, and phase transformation behavior of polymorphs and the hydrate of 4-amino-3,5-dinitrobenzamide. The compound crystallizes in four different polymorphic forms, Form I (monoclinic, P2(1)/n), Form II (orthorhombic, Pbca), Form III (monoclinic, P2(1)/c), and Form IV (monoclinic, P2(1)/c). Interestingly, a hydrate (triclinic, P (1) over bar) of the compound is also discovered during the systematic identification of the polymorphs. Analysis of the polymorphs has been investigated using hot stage microscopy, differential scanning calorimetry, in situ variable-temperature powder X-ray diffraction, and single-crystal X-ray diffraction. On heating, all of the solid forms convert into Form I irreversibly, and on further heating, melting is observed. In situ single-crystal X-ray diffraction studies revealed that Form II transforms to Form I above 175 degrees C via single-crystal-to-single-crystal transformation. The hydrate, on heating, undergoes a double phase transition, first to Form III upon losing water in a single-crystal-to-single-crystal fashion and then to a more stable polymorph Form I on further heating. Thermal analysis leads to the conclusion that Form II appears to be the most stable phase at ambient conditions, whereas Form I is more stable at higher temperature