The efficacy of Zafirlukast as a SARS-CoV-2 helicase inhibitor in adult patients with moderate COVID-19 Pneumonia (pilot randomized clinical trial).

OBJECTIVE: To assess the efficacy of Zafirlukast as a SARS-CoV-2 Helicase Inhibitor in adult patients with moderate COVID-19 symptoms (hospitalized patients with COVID-19 pneumonia who were not admitted to an intensive care unit). METHODS: We conducted a randomized, double blind, placebo-controlled, pilot trial with adult patients with moderate COVID-19 pneumonia. The sample was randomized to Zafirlukast 10 mg BD for 10 days plus standard care vs placebo plus standard care. The primary outcome was the complete resolution of all symptoms. The secondary outcomes were the duration of oxygen therapy, and length of hospital stay (LOS). RESULTS: In total, 40 patients were randomized (20 to Zafirlukast and 20 to the control). The time to the resolution of clinical symptoms in both groups was not significantly different. Regarding the fever, 0.3 days [95 % CI, - 1.19, 0.69], p = 0.76, for shortness of breath, the difference was 0.4 days [95 % CI, - 2.67, 3.46], p = 0.68, for cough the difference was 0.2 days [95 % CI, - 1.45, 1.95], p = 0.98, for sputum the difference was 0.5 days [95 % CI, - 0.75, 1.85], p = 0.09, for vomiting the difference was 0.1 days [95 % CI, - 0.50, 0.30], p = 0.93, for fatigue the difference was 0.3 days [95 % CI, - 4.32, 3.62], p = 0.64. The LOS per day for the two groups was not significantly different, 1.1 days [95 % CI,- 2.03, 4.28], p = 0.94, nor was the duration of oxygen therapy per days, 1.3 days [95 % CI, - 1.79, 4.49], p = 0.49. Regarding the 7 category ordinary scale, there was no significant difference between the two groups at day 7 (p-value = 0.62), day 14 (p-value = 0.60) and day 28 (p-value = 0.48). CONCLUSION: Among adult patients hospitalized with COVID-19 pneumonia, the treatment with Zafirlukast, compared to placebo, did not significantly improve symptoms resolution.

Discovery of Zafirlukast as a novel SARS-CoV-2 helicase inhibitor using in silico modelling and a FRET-based assay.

The coronavirus helicase is an essential enzyme required for viral replication/transcription pathways. Structural studies revealed a sulphate moiety that interacts with key residues within the nucleotide-binding site of the helicase. Compounds with a sulphoxide or a sulphone moiety could interfere with these interactions and consequently inhibit the enzyme. The molecular operating environment (MOE) was used to dock 189 sulphoxide and sulphone-containing FDA-approved compounds to the nucleotide-binding site. Zafirlukast, a leukotriene receptor antagonist used to treat chronic asthma, achieved the lowest docking score at -8.75 kcals/mol. The inhibitory effect of the compounds on the SARS-CoV-2 helicase dsDNA unwinding activity was tested by a FRET-based assay. Zafirlukast was the only compound to inhibit the enzyme (IC50 = 16.3 µM). The treatment of Vero E6 cells with 25 µM zafirlukast prior to SARS-CoV-2 infection decreased the cytopathic effects of SARS-CoV-2 significantly. These results suggest that zafirlukast alleviates SARS-CoV-2 pathogenicity by inhibiting the viral helicase and impairing the viral replication/transcription pathway. Zafirlukast could be clinically developed as a new antiviral treatment for SARS-CoV-2 and other coronavirus diseases. This discovery is based on molecular modelling, in vitro inhibition of the SARS-CoV helicase activity and cell-based SARS-CoV-2 viral replication.

Using in silico modelling and FRET-based assays in the discovery of novel FDA-approved drugs as inhibitors of MERS-CoV helicase.

A Förster resonance energy transfer (FRET)-based assay was used to screen the FDA-approved compound library against the MERS-CoV helicase, an essential enzyme for virus replication within the host cell. Five compounds inhibited the helicase activity with submicromolar potencies (IC50, 0.73-1.65 µM) and ten compounds inhibited the enzyme with micromolar potencies (IC50, 19.6-502 µM). The molecular operating environment (MOE) was used to dock the identified inhibitors on the MERS-CoV helicase nucleotide binding. Strong inhibitors docked well in the nucleotide-binding site and established interactions with some of the essential residues. There was a reasonable correlation between the observed IC50 values and the MOE docking scores of the strong inhibitors (r 2 = 0.74), indicating the ability of the in silico docking model to predict the binding of strong inhibitors. In silico docking could be a useful complementary tool used with the FRET-based assay to predict new MERS-CoV helicase inhibitors. The identified inhibitors could potentially be used in the clinical development of new antiviral treatment for MERS-CoV and other coronavirus related diseases, including coronavirus disease 2019 (COVID-19).

Acute metabolic responses of postpartal dairy cows to subcutaneous glucagon injections, oral glycerol, or both.

This study examined the effects of multiple subcutaneous glucagon injections with or without co-administration of oral glycerol on energy status-related blood metabolites and hormones of Holstein dairy cows in the first 2 wk postpartum. Twenty multiparous cows were fed a dry cow ration supplemented with 6 kg of cracked corn during the dry period to increase the likelihood of developing postpartal fatty liver syndrome. Cows with a body condition score of >or=3.5 points (1- to 5-point scale) were assigned randomly to 1 of 4 treatment groups: saline, glucagon, glycerol, or glucagon plus glycerol. Following treatment, serial blood samples were collected over an 8-h period to determine the effects of glucagon and glycerol on blood metabolites and hormones. Treatment effects were determined by comparing the concentrations of metabolites and hormones during the first 4-h period and the entire 8-h period after treatment administration (time 0) with the concentration of the same compounds at time 0 on d 1, 7, and 13 postpartum. Administration of glucagon alone increased concentrations of plasma glucagon and insulin on d 1, 7, and 13 and increased plasma glucose and decreased plasma nonesterified fatty acids (NEFA) on d 7 and 13 postpartum relative to the saline group. Administration of glycerol alone increased plasma glucose on d 7 and plasma triacylglycerols on d 1 postpartum. Glycerol administration also decreased plasma glucagon and NEFA on d 1, 7, and 13 and plasma beta-hydroxybutyrate (BHBA) on d 1 postpartum relative to the saline group. Administration of glucagon plus glycerol increased and sustained concentrations of plasma glucagon, glucose, and insulin on d 1, 7, and 13 and decreased plasma NEFA on d 1, 7, and 13 and BHBA on d 1 and 7. Early postpartal treatment of dairy cows with glucagon plus glycerol increased plasma glucose and insulin, decreased plasma NEFA and BHBA, and increased secretion of liver NEFA as plasma triacylglycerols. This suggests that glucagon and glycerol, when co-administered, act to decrease the likelihood of metabolism-related syndrome development in dairy cows.

Hepatitis C virus infection in hemodialysis patients in jordan.

To evaluate the prevalence of hepatitis C virus infection in our hemodialysis population, we carried out a survey of 273 adult hemodialysis patients in three hemodialysis units in Jordan using a second generation rapid enzyme immunoassay. Sixty seven patients were seropositive with a prevalence of 24.5%. All patients were transfusion dependent except two. More than 85% of the patients have been on hemodialysis for more than two years. Co-infection with hepatitis B virus was observed in six patients. Abnormal liver functions were seen in five patients, but liver biopsies were not done. The prevalence of hepatitis C antibody in healthy blood donors in Jordan is 1.7%. We conclude that HCV infection prevalence in hemodialysis patients in Jordan is 24.5%, a percentage similar to what has been reported around the world and in the neighboring countries.