scholarly journals Nanoviricides platform technology based NV-CoV-2 polymer increases the half-life of Remdesivir in vivo

2021 ◽  
Author(s):  
Ashok Chakraborty ◽  
Anil Diwan ◽  
Vinod Arora ◽  
Yogesh Thakur ◽  
Vijetha Chiniga ◽  
...  

So far, there are seven coronaviruses identified that infect humans and only 4 of them belong to the beta family of coronavirus (HCoV-HKU1, SARS-CoV-2, MERS-CoV and SARS-CoV). SARS family are known to cause severe respiratory disease in humans. In fact, SARS-CoV-2 infection caused a pandemic COVID-19 disease with high morbidity and mortality. Remdesivir (RDV) is the only antiviral drug so far approved for COVID-19 therapy by the FDA. However, the efficacy of RDV in vivo is limited due to its low stability in presence of plasma. This is the report of analysis of the non-clinical pharmacology study of NV-CoV-2 (Polymer) and NV-CoV-2-R (Polymer encapsulated Remdesivir) in both infected and uninfected rats with SARS-CoV-2. Detection and quantification of NV-CoV-2-R in plasma samples was done by MS-HPLC chromatography analyses of precipitated plasma samples from rat subjects. (i) NV-CoV-2-R show RDV peak in MS-HPLC chromatography, whereas only NV-CoV-2 does not show any RDV-Peak, as expected. (ii) NV-CoV-2 polymer encapsulation protects RDV in vivo from plasma-mediated catabolism. (iii) Body weight measurements of the normal (uninfected) rats after administration of the test materials (NV-CoV-2, and NV-CoV-2-R) show no toxic effects on them. Our platform technology based NV-387-encapsulated-RDV (NV-CoV-2-R) drug has a dual effect on coronaviruses. First, NV-CoV-2 itself as an antiviral regimen. Secondly, RDV is protected from plasma-mediated degradation in transit, rendering altogether the safest and an efficient regimen against COVID-19.

2021 ◽  
Author(s):  
Ashok Chakraborty ◽  
Anil Diwan ◽  
Vijetha Chiniga ◽  
Vinod Arora ◽  
Preetam Holkar ◽  
...  

Remdesivir (RDV) is the only antiviral drug so far approved for COVID-19 therapy by the FDA. However its efficacy is limited in vivo due to its low stability in presence of plasma. This paper compared the stability of RDV encapsulated with our platform technology based polymer NV-387 (NV-CoV-2), in presence of plasma in vitro and in vivo . Furthermore, a non-clinical pharmacology studies of NV-CoV-2 (Polymer) and NV-CoV-2-R (Polymer encapsulated Remdesivir ) in both NL-63 infected and uninfected rats were done. In an in vitro cell culture model experiment, antiviral activity of NV-CoV-2 and NV-CoV-2-R are also compared with RDV.


1996 ◽  
Vol 76 (04) ◽  
pp. 549-555 ◽  
Author(s):  
Walter A Wuillemin ◽  
C Erik Hack ◽  
Wim K Bleeker ◽  
Bart J Biemond ◽  
Marcel Levi ◽  
...  

SummaryC1-inhibitor (C1Inh), antithrombin III (ATIII), α1-antitrypsin (a1AT), and α2-antiplasmin (a2AP) are known inhibitors of factor XIa (FXIa). However, their precise contribution to FXIa inactivation in vivo is not known. We investigated FXIa inactivation in chimpanzees and assessed the contribution of these inhibitors to FXIa inactivation in patients with presumed FXI activation.Chimpanzees were infused with FXIa and the various FXIa-FXIa inhibitor complexes formed were measured. Most of FXIa was complexed to C1Inh (68%), followed by a2AP (13%), a1AT (10%), and ATIII (9%). Analysis of the plasma elimination kinetics revealed a half-life time of clearance (t1/2) for the FXIa-FXIa inhibitor complexes of 95 to 104 min, except for FXIa-a1AT, which had a t1/2 of 349 min. Due to this long t1/2, FXIa-a1AT complexes were predicted to show the highest levels in plasma samples from patients with activation of FXI. This was indeed shown in patients with disseminated intravascular coagulation, recent myocardial infarction or unstable angina pectoris. We conclude from this study that in vivo C1Inh is the predominant inhibitor of FXIa, but that FXIa-a1 AT complexes due to their relatively long t1/2 may be the best parameter to assess FXI activation in clinical samples.


1995 ◽  
Vol 74 (02) ◽  
pp. 673-679 ◽  
Author(s):  
C E Dempfle ◽  
S A Pfitzner ◽  
M Dollman ◽  
K Huck ◽  
G Stehle ◽  
...  

SummaryVarious assays have been developed for quantitation of soluble fibrin or fibrin monomer in clinical plasma samples, since this parameter directly reflects in vivo thrombin action on fibrinogen. Using plasma samples from healthy blood donors, patients with cerebral ischemic insult, patients with septicemia, and patients with venous thrombosis, we compared two immunologic tests using monoclonal antibodies against fibrin-specific neo-epitopes, and two functional tests based on the cofactor activity of soluble fibrin complexes in tPA-induced plasminogen activation. Test A (Enzymun®-Test FM) showed the best discriminating power among normal range and pathological samples. Test B (Fibrinostika® soluble fibrin) clearly separated normal range from pathological samples, but failed to discriminate among samples from patients with low grade coagulation activation in septicemia, and massive activation in venous thrombosis. Functional test C (Fibrin monomer test Behring) displayed good discriminating power between normal and pathological range samples, and correlated with test A (r = 0.61), whereas assay D (Coa-Set® Fibrin monomer) showed little discriminating power at values below 10 μg/ml and little correlation with other assays. Standardization of assays will require further characterization of analytes detected.


2019 ◽  
Vol 25 (36) ◽  
pp. 3872-3880 ◽  
Author(s):  
Marcel M. Bergmann ◽  
Jean-Christoph Caubet

Severe cutaneous adverse reactions (SCAR) are life-threatening conditions including acute generalized exanthematous pustulosis (AGEP), Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN) and drug reaction with eosinophilia and systemic symptoms (DRESS). Diagnosis of causative underlying drug hypersensitivity (DH) is mandatory due to the high morbidity and mortality upon re-exposure with the incriminated drug. If an underlying DH is suspected, in vivo test, including patch tests (PTs), delayed-reading intradermal tests (IDTs) and in vitro tests can be performed in selected patients for which the suspected culprit drug is mandatory, or in order to find a safe alternative treatment. Positivity of in vivo and in vitro tests in SCAR to drug varies depending on the type of reaction and the incriminated drugs. Due to the severe nature of these reactions, drug provocation test (DPT) is highly contraindicated in patients who experienced SCAR. Thus, sensitivity is based on positive test results in patients with a suggestive clinical history. Patch tests still remain the first-line diagnostic tests in the majority of patients with SCAR, followed, in case of negative results, by delayed-reading IDTs, with the exception of patients with bullous diseases where IDTs are still contra-indicated. In vitro tests have shown promising results in the diagnosis of SCAR to drug. Positivity is particularly high when the lymphocyte transformation test (LTT) is combined with cytokines and cytotoxic markers measurement (cyto-LTT), but this still has to be confirmed with larger studies. Due to the rarity of SCAR, large multi-center collaborative studies are needed to better study the sensitivity and specificity of in vivo and in vitro tests.


2020 ◽  
Vol 16 ◽  
Author(s):  
Xi He ◽  
Wenjun Hu ◽  
Fanhua Meng ◽  
Xingzhou Li

Background: The broad-spectrum antiparasitic drug nitazoxanide (N) has been repositioned as a broad-spectrum antiviral drug. Nitazoxanide’s in vivo antiviral activities are mainly attributed to its metabolitetizoxanide, the deacetylation product of nitazoxanide. In reference to the pharmacokinetic profile of nitazoxanide, we proposed the hypotheses that the low plasma concentrations and the low system exposure of tizoxanide after dosing with nitazoxanide result from significant first pass effects in the liver. It was thought that this may be due to the unstable acyloxy bond of nitazoxanide. Objective: Tizoxanide prodrugs, with the more stable formamyl substituent attached to the hydroxyl group rather than the acetyl group of nitazoxanide, were designed with the thought that they might be more stable in plasma. It was anticipated that these prodrugs might be less affected by the first pass effect, which would improve plasma concentrations and system exposure of tizoxanide. Method: These O-carbamoyl tizoxanide prodrugs were synthesized and evaluated in a mouse model for pharmacokinetic (PK) properties and in an in vitro model for plasma stabilities. Results: The results indicated that the plasma concentration and the systemic exposure of tizoxanide (T) after oral administration of O-carbamoyl tizoxanide prodrugs were much greater than that produced by equimolar dosage of nitazoxanide. It was also found that the plasma concentration and the systemic exposure of tizoxanide glucuronide (TG) were much lower than that produced by nitazoxanide. Conclusion: Further analysis showed that the suitable plasma stability of O-carbamoyl tizoxanide prodrugs is the key factor in maximizing the plasma concentration and the systemic exposure of the active ingredient tizoxanide.


2019 ◽  
Vol 15 (7) ◽  
pp. 776-784
Author(s):  
Xiaonian Han ◽  
Jing Wang ◽  
Jing Huang ◽  
Lirong Peng

Background: As first-line treatments for diabetes, sitagliptin and metformin have been widely prescribed as a combination to enhance the therapeutic effect. Objective: To establish a methodology to simultaneously monitor the two drugs in vivo by a reversedphase Liquid Chromatography-Tandem Mass Spectrometric (LC-MS/MS) method. Methods: The two drugs were extracted from 50 μl human plasma by ion-pair solid phase extraction. The separation of the plasma samples was implemented on an Agilent Zorbax SB-CN column (150×4.6 mm, 5.0 µm). The mobile phase was the mixture (80:20, v/v) of methanol and 5.0 mM ammonium formate in water (pH 4.5). An ion trap spectrometer equipped with an electrospray ionization source was utilized to detect the elution in positive mode. Quantification of the analytes was achieved by Multiple Reaction Monitoring (MRM) using the transitions of m/z 408.3→235.1 for sitagliptin and m/z 130.1→ 60.2 for metformin. Results: Sitagliptin and metformin demonstrated good linearity among the range of 1.00-1000 ng/mL and 5.00-4000 ng/mL. The intra-day and inter-day investigations displayed precisions of ≤ 3.6% and an accuracy range of -7.5% to 6.0% for the two drugs. The mean recovery of the two drugs was 96.0% and 98.5%. Under mandatory storage conditions, both the drugs gave an acceptable stability. The throughput of the assay was found to be more than 100 plasma samples per day ascribed to the run time of 3.0 min for each sample. Conclusion: The developed method was successfully applied to a pharmacokinetic study for a fixeddose tablet formulation containing 50 mg sitagliptin and 500 mg metformin in 12 healthy volunteers.


Author(s):  
B Lefrère ◽  
D Wohrer ◽  
C Godefroy ◽  
M Soichot ◽  
A Mihoubi ◽  
...  

Abstract We report the case of an 11-month-old male infant with a complex congenital heart disease who was admitted in the intensive care unit following cardiorespiratory arrest at home. Toxicological urine screening reported an ethanol concentration of 0.65 g/L using an enzymatic assay, without suspicion of alcohol intake; a significant amount of ethanol concentration was found in two plasma samples using the same enzymatic assay. Plasma and urine ethanol concentrations were below the limit of quantification (LOQ) when tested using a gas chromatography method. Urine ethanol level was also below the LOQ when tested by enzymatic assay after an initial urine ultrafiltration. These results confirmed our suspicion of matrix interference due to elevated lactate and lactate dehydrogenase levels interfering in the enzymatic assay. This analytical interference, well-known in postmortem samples, extensively studied in vitro, has been rarely reported in vivo, especially in children. To the best of our knowledge, this case is only the sixth one reported in an infant’s plasma and the first initially discovered from urine. Indeed, as for ethanol, this last matrix has not been studied in the context of this artifact that may induce false-positive ethanol results while seeking a diagnosis in life-threatening or fatal situations that are potentially subject to forensic scrutiny. In parallel to a synthetic literature review, we propose a simple, informative decision tree, in order to help health professionals suspecting a false-positive result when performing an ethanol assay.


Author(s):  
He Zhu ◽  
Hongwei Zhang ◽  
Youliang Pei ◽  
Zhibin Liao ◽  
Furong Liu ◽  
...  

Abstract Background Hepatocellular carcinoma (HCC) is a common type of malignant human cancer with high morbidity and poor prognosis, causing numerous deaths per year worldwide. Growing evidence has been demonstrated that long non-coding RNAs (lncRNAs) are closely associated with hepatocarcinogenesis and metastasis. However, the roles, functions, and working mechanisms of most lncRNAs in HCC remain poorly defined. Methods Real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression level of CCDC183-AS1 in HCC tissues and cell lines. Cell proliferation, migration and invasion ability were evaluated by CCK-8 and transwell assay, respectively. Animal experiments were used to explore the role of CCDC183-AS1 and miR-589-5p in vivo. Bioinformatic analysis, dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were performed to confirm the regulatory relationship between CCDC183-AS1, miR-589-5p and SKP1. Results Significantly upregulated expression of CCDC183-AS1 was observed in both HCC tissues and cell lines. HCC patients with higher expression of CCDC183-AS1 had a poorer overall survival rate. Functionally, overexpression of CCDC183-AS1 markedly promoted HCC cell proliferation, migration and invasion in vitro and tumor growth and metastasis in vivo, whereas the downregulation of CCDC183-AS1 exerted opposite effects. MiR-589-5p inhibitor counteracted the proliferation, migration and invasion inhibitory effects induced by CCDC183-AS1 silencing. Mechanistically, CCDC183-AS1 acted as a ceRNA through sponging miR-589-5p to offset its inhibitory effect on the target gene SKP1, then promoted the tumorigenesis of HCC. Conclusions CCDC183-AS1 functions as an oncogene to promote HCC progression through the CCDC183-AS1/miR-589-5p/SKP1 axis. Our study provided a novel potential therapeutic target for HCC patients.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jiantao Wang ◽  
Jinbiao Che

Abstract Background Hepatocellular carcinoma (HCC) is the leading cause of tumor-related death worldwide due to high morbidity and mortality, yet lacking effective biomarkers and therapies. Circular RNAs (circRNAs) are a group of non-coding RNAs that regulate gene expression through interacting with miRNAs, implicating in the tumorigenesis and progression. A novel circRNA, circTP63, was reported to be an oncogene in HCC. However, its role in HCC remains unclear. Methods qRT-PCR was used to assess the mRNA levels of CircTP63 in 90 pairs of tumor and adjacent normal tissues from HCC patients, one human normal hepatic epithelial cell line and HCC cell lines. CCK-8, colony formation, transwell, and flow cytometry assays were performed to detect the cellular function of circTP63/miR-155-5p/ZBTB18 in HCC cells. HCC xenograft mice models were established to assess the in vivo effect of circTP63. Bioinformatic analysis, RNA pull-down and luciferase assays were used to determine the interaction among circTP63/miR-155-5p/ZBTB18. Results circTP63 was significantly upregulated in HCC tissues and cell lines. High circTP63 expression is closely associated with the tumor stages, lymph node metastasis, and poor prognosis of HCC patients. Functionally, knockdown of circTP63 inhibited cell proliferation, migration, invasion, and promoted cell apoptosis of HCC. Meanwhile, overexpression of circTP63 enhanced HCC progression. Mechanically, circTP63 was a sponge of miR-155-5p to facilitate the ZBTB18 expression, and the ZBTB18 expression in HCC tissues was negatively associated with the survival rate of HCC patients. Furthermore, rescued assays revealed that the reduced tumor-promoting effect on HCC cells induced by knockdown of circTP63 can be reversed by miR-155-5p inhibitor or ZBTB18 overexpression. Conclusion Our data highlight a critical circTP63-miR-155-5p-ZBTB18 regulatory network involved in the HCC progression, gaining mechanistic insights into the function of circRNAs in HCC progression, and providing effective biomarkers and therapeutic targets for HCC treatment.


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