Sofosbuvir Research Articles

Efficacy of 8-week daclatasvir-sofosbuvir regimen in chronic hepatitis C: a systematic review and meta-analysis

BackgroundThe high rates of the sustained virologic response 12 weeks after treatment (SVR12) in real world settings provoked the adoption of shortened courses of the costly direct-acting antivirals (DAAs) regimens. This study provides, to our knowledge, the first systematic review and meta-analysis for the efficacy of the shortened 8-week course of sofosbuvir (SOF) plus daclatasvir (DCV), the most accessible DAAs in the low-middle income countries (LMICs).MethodsWe performed a proportion meta-analysis to determine a reliable rate of SVR12 by pooling all studies that evaluated the results of the 8-week regimen of DCV + SOF. In addition, we applied sensitivity analyses using two imputation paradigms: a conservative approach, and a pragmatic approach to avoid overestimating the efficacy of the 8-week regimen in studies that followed a response-guided treatment (RGT) approach.ResultsSix studies with a total of 159 patients were included. The pooled SVR12 rate ranged from 91 to 97% in the included scenarios. The pragmatic scenario showed that the pooled SVR12 was 97% (95% confidence interval (CI) 91%; 100%) with lower variability as assessed by the prediction interval. The conservative approach revealed an SVR12 of 93% (95% CI 84%; 95%).ConclusionThe 8-week course of 60 mg DCV with SOF provided a comparable SVR12 to the standard 12-week regimen in treatment-naïve, non-HIV co-infected patients with a minimum estimated efficacy of 90%.

Rapid and sensitive colorimetric assay based on aggregation of gold nanoparticles coupled with fuzzy inference system for the trace determination of sofosbuvir and ledipasvir as anti-hepatitis F in binary mixture

A facile, rapid, low-cost, and sensitive gold nanoparticle (AuNP)-based colorimetric method was introduced to analyze sofosbuvir (SOF) and ledipasvir (LED) simultaneously in laboratory binary mixtures and pharmaceutical formulation samples using fuzzy inference system (FIS). The synthesized AuNPs before and after adding the drug were characterized using Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and dynamic light scattering (DLS). After adding the drug to AuNPs solution, the color change from wine red (520 nm) to grey (660 nm) occurred due to the aggregation of AuNPs and the surface plasmon resonance (SPR) in the visible region. A linear calibration curve was in the range from 10 to 100 and 20–100 mg/L with a limit of detection and limit of quantification of 9.57, 29.07 μg/L and 8.58, 26.15 μg/L for SOF and LED, respectively. FIS along with principal component analysis (PCA) was used for the simultaneous determination of SOF and LED. The mean recovery values were found to be 101.07 % and 99.58 %, and the root mean square error (RMSE) was 1.1455 and 1.2138 for SOF and LED, respectively. The results obtained from the analysis of real sample by FIS-PCA and HPLC were compared via an ANOVA test and no significant difference was observed. The results indicated that the developed optical method has high precision, accuracy, and sensitivity for the analysis of pharmaceutical components in binary mixtures, which can be faster and less expensive than chromatography methods.

Safety and efficacy of sofosbuvir/ledipasvir combination in treatment of chronic hepatitis C infection in adolescents aged 12–17 years old

BackgroundChronic hepatitis C virus (CHC) infection represents a crucial health problem, especially among children and adolescents. The ledipasvir (LDV)/sofosbuvir (SOF) regimen has been approved to treat adolescents (aged 12 to 17 years old) infected with hepatitis C virus (HCV) genotypes 1, 4, 5, and 6 and then extended to include children above or equal to 3 years old. The current study aims to evaluate the safety and efficacy of SOF/LDV combination in treating CHC-infected 12- to 17-year-old adolescents.Patients and methodsThis retrospective cohort study was performed on 147 Egyptian adolescents with CHC. The patients were treated with SOF 400 mg/LDV 90 mg combination once daily for 12 weeks. Possible side effects and laboratory data including HCV ribonucleic acid polymerase chain reaction (RNA PCR), complete blood count (CBC), and liver tests were recorded at baseline and week 12 after the end of treatment (EOT).ResultsSustained virological response 12 weeks (SVR12) after end of treatment (EOT) was observed in 146 out of 147 patients (99.3%). The treatment regimen was efficiently tolerated with no reported cases of discontinuation caused by intolerability. Moreover, the side effects were minimal; 71.4% of the patients did not report any side effects related to the treatment. However, the rest mentioned fatigue, headache, or both of them. Fatigue was the main side effect reported in 16.3% of the patients. Furthermore, ALT and AST levels were normalized after treatment. FIB-4 and APRI scores were statistically significantly decreased 2 years post-SVR, in comparison to their levels before treatment, from 0.34 and 0.36 to 0.25 and 0.17, respectively.ConclusionThe LDV/SOF regimen is one of the safe regimens used to treat adolescent patients with CHC infection.

Generic sofosbuvir and daclatasvir for treatment of hepatitis C virus infection in patients with sickle cell disease

Background and purpose of the studySickle cell disease (SCD) patients are at a high risk of chronic liver disease (CLD) due to chronic viral hepatitis infection such as hepatitis C virus (HCV) infection, iron overload, and sickle cell hepatopathy. Nowadays, several oral direct-acting antiviral drugs (DAAs) have been developed and approved by the FDA for hepatitis C treatment. However, the safety and efficacy of DAAs in SCD patients remain insufficiently explored.Purpose of the studyTo evaluate the efficacy and safety of administration of generic sofosbuvir (SOF) and daclatasvir (DCV) for 12 weeks in SCD patients infected with HCV.MethodsA retrospective study included 38 SCD patients infected with HCV treated with generic SOF (400 mg) and DCV (60 mg) for 12 weeks without ribavirin. The effectiveness of the HCV treatment was assessed by the sustained virologic response (SVR) at 24 weeks after the end of the treatment (SVR24).ResultsThe SVR24 rate was 100% (38/38).There were insignificant alterations in hemoglobin and total bilirubin levels during HCV treatment or at end of treatment (EOT). The number of anemic patients who needed blood transfusion two weeks before HCV treatment, at week 4 of treatment, and at EOT was 11 (28.9%), 3 (8%), and 1 (3%) respectively. Moreover, the reductions in serum transaminase levels from baseline were statistically significant compared to the EOT.ConclusionGeneric SOF and DCV regimens appear to be safe and effective in the treatment of chronic HCV in patients with SCD.

Effect of carvedilol on pharmacokinetics of sofosbuvir and its metabolite GS-331007: role of P-glycoprotein.

Sofosbuvir (SOF) is a P-glycoprotein (P-gp) substrate, and carvedilol (CAR) is an inhibitor of P-gp, suggesting that it may affect the oral pharmacokinetics and safety of SOF. The current study investigated the pharmacokinetic interaction of CAR with SOF and its metabolite, GS-331007, and the possible consequent toxicities in rats. To assess the pharmacokinetics of SOF and GS-331007, rats were divided into three groups; all received a single oral dose of SOF preceded with saline (SAL), verapamil (VER) as a standard P-gp inhibitor, or CAR, respectively. The serosal, plasma, and hepatic tissue contents of SOF and GS-331007 were assessed using LC-MS/MS. Renal and hepatic toxicities were assessed using biochemical and histopathological tests. Serosal and plasma concentrations of SOF and GS-331007 were increased in the presence of CAR, suggesting a significant inhibitory effect of CAR on intestinal P-gp. Simultaneously, the pharmacokinetic profile of SOF showed a significant increase in the Cmax, AUC(0-t), AUC (0-∞), t1/2, and a reduction in its apparent oral clearance. While the pharmacokinetic profile of GS-331007 was not significantly affected. However, this notable elevation in drug oral bioavailability was corroborated by a significant alteration in renal functions. Hence, further clinical investigations are recommended to ensure the safety and dosing of CAR/SOF combination.

Meta-Analysis of the Effectiveness of Sofosbuvir-Based Regimens in Treating Hepatitis C Genotype 3

Hepatitis C virus (HCV) is an RNA virus with seven primary genotypes. It is highly prevalent in Pakistan, especially genotype 3. HCV infection can progress to a chronic state with further complications. Direct-acting antiviral agents (DAAV) were introduced in 2014 as a treatment option, some of which include Sofosbuvir (SOF), Daclatasvir (DCV), Velpatasvir (VEL) and Ribavirin (RV). This meta-analysis was performed to outline the treatment response and efficacy of DAAV in HCV infected patients. We systematically searched PubMed, Web of Science, MEDLINE, and Google Scholar for studies from January 2019 to December 2023. The studies selected met the criteria of patients having chronic HCV infection (genotype 3) and either compensated cirrhosis or decompensated chronic liver disease. Treatment regimens with DAAV specifically were included. The primary outcomes [sustained viral response (SVR), rapid virological response (RVR), end-of-treatment response (ETR)] were highlighted to assess treatment response. The studies proved that the use of direct-acting antiviral agents in different combinations was very effective against HCV infection with minimal side-effects.

Prognosis Following Sustained Virologic Response in Korean Chronic Hepatitis C Patients Treated with Sofosbuvir-Based Treatment: Data from a Multicenter Prospective Observational Study up to 7 Years.

Background and Objectives: Chronic hepatitis C (CHC) can be cured with direct-acting antiviral (DAA) therapy. In Korea, sofosbuvir (SOF) and ledipasvir (LDV)/SOF were launched in 2016. Patients who achieve a sustained virologic response (SVR) following DAA treatment are predicted to have a favorable prognosis. Nevertheless, little is known regarding the prognosis of Korean CHC patients who receive SOF-based treatment and achieve SVR. Therefore, the purpose of this study was to look into the long-term outcomes for these patients. Materials and Methods: This was a prospective, multicenter observational study. CHC patients were enrolled who, following SOF or LDV/SOF treatment, had achieved SVR. The last day for follow-up was December 2023. The primary endpoint was HCC occurrence, which was checked at least once per year. Results: A total of 516 patients were included in this analysis, with a median follow-up duration of 39.0 months. Among them, 231 were male patients (44.8%), with a median age of 62.0 years. Genotypes were 1 (90, 17.4%), 2 (423, 82.0%), and 3 (3, 0.6%). The combination of SOF plus ribavirin was the most common treatment (394, 76.4%). In total, 160 patients were cirrhotic (31.0%), and the mean Child-Pugh score was 5.1. Within a maximum of 7 years, 21 patients (4.1%) developed HCC. Patients with HCC were older (69 vs. 61 years, p = 0.013) and had a higher cirrhosis incidence (81.0 vs. 28.9%, p < 0.001), higher AFP (6.0 vs. 3.3, p = 0.003) and higher APRI (0.8 vs. 0.5, p = 0.005). Age over 65 (p = 0.016) and cirrhosis (p = 0.005) were found to be significant risk factors for HCC by Cox regression analysis. Conclusions: Patients who achieved SVR with SOF-based treatment had a relatively favorable prognosis. However, the risk of HCC was not eliminated, especially in older and cirrhotic patients. Therefore, routine follow-up, surveillance, and early treatment are required.

Development and validation of colorimetric-assisted chemometrics methods based on the localized gold nanoparticles surface plasmon resonance for fast simultaneous estimation of anti-hepatitis C virus drugs in their combined dosage form: A comparative study with HPLC method

The present work describes a developed analytical method based on a colorimetric assay using gold nanoparticles (AuNPs) along with chemometric techniques for the simultaneous estimation of sofosbuvir (SOF) and ledipasvir (LED) in their synthetic mixtures and tablet dosage form. The applied chemometric approaches were continuous wavelet transform (CWT) and least squares support vector machine (LS-SVM). Characterization of AuNPs and AuNPs in combination with the drug was performed by UV–vis spectrophotometer, transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier transform infrared (FTIR) spectroscopy. In the CWT method, the zero amplitudes were determined at 427 nm with Daubechies wavelet family for SOF (zero crossing point of LED) and 440 nm with Symlet wavelet family for LED (zero crossing point of SOF) over the concentration range of 7.5–90.0 μg/L and 40.0–100.0 μg/L with coefficients of determination (R2) of 0.9974 and 0.9907 for SOF and LED, respectively. The limit of detection (LOD) and limit of quantification (LOQ) of this method were found to be 7.92, 9.96 μg/L and 12.02, 30.2 μg/L for SOF and LED, respectively. In the LS-SVM model, the mean percentage recovery of SOF and LED in synthetic mixtures was 98.29 % and 99.25 % with root mean square error of 2.392 and 1.034, which were obtained by the optimization of regularization parameter (γ) and width of the function (σ) based on the cross-validation method. The proposed methods were also applied for the determination concentration of SOF and LED in the combined dosage form, recoveries were higher than 95 %, and relative standard deviation (RSD) values were lower than 0.4 %. The achieved results were statistically compared with those obtained from the high-performance liquid chromatography (HPLC) technique for the concurrent estimation of components through one-way analysis of variance (ANOVA), and no significant difference was found between the suggested approaches and the reference one. According to these results, simplicity, high speed, lack of time-consuming process, and cost savings are considerable benefits of colorimetry along with chemometrics methods compared to other ways.

Analytical Profile of Antiviral Drugs-Remdesivir, Simeprevir, and Sofosbuvir: A Review

Remdesivir (RDV) is an antiviral drug and a phosphonamidite prodrug designed to have activity against a broad spectrum of viruses, act as a nucleoside analogue, and inhibit the RNA-dependent RNA polymerase [RDRP] of coronaviruses, including SARS-CoV-2, whereas Simeprevir (SMV) and Sofosbuvir (SFS) are direct-acting antiviral drugs approved for the treatment of chronic Hepatitis C virus (HCV) infection. Reports show that the structure and replication mechanism of HCV and SARS-COV-2 are comparable. Hepatitis C virus protease inhibitors include Simeprevir. Because it is an NS3/4A protease inhibitor, it inhibits protein synthesis, which stops viruses from maturing. A nucleotide analogue inhibitor called sofosbuvir selectively blocks the RNA-dependent RNA polymerase of HCV NS5B (non-structural protein 5B). This review article gathers and discusses the range of analytical techniques—UV, HPLC, and hyphenated procedures like LC-MS—that are available in the literature for the determination of RDV, SMV, and SFS. This review article can be effectively explored to conduct future analytical investigation for the estimation of the selected drugs in pharmaceutical and biological samples.

Novel Strategy for Screening Target Proteins by the Common Drugs─Sofosbuvir-Specific Profiling of HCV Patient Serum.

It is the scientific basis of precision medicine to study all of the targets of drugs based on the interaction between drugs and proteins. It is worth paying attention to unknown proteins that interact with drugs to find new targets for the design of new drugs. Herein, we developed a protein profiling strategy based on drug-protein interactions and drug-modified magnetic nanoparticles and took hepatitis C virus (HCV) and its corresponding drug sofosbuvir (SOF) as an example. A SOF-modified magnetic separation medium (Fe3O4@POSS@SOF) was prepared, and a gradient elution strategy was employed and optimized to profile specific proteins interacted with SOF. A series of proteomic analyses were performed to profile proteins based on SOF-protein interactions (SPIs) in the serum of HCV patients to evaluate the specificity of the profiling strategy. As a result, five proteins were profiled with strong SPIs and exhibited high relevance with liver tissue, which were potentially new drug targets. Among them, HSP60 was used to confirm the highly specific interactions between the SOF and its binding proteins by Western blotting analysis. Besides, 124 and 29 differential proteins were profiled by SOF material from three HCV patient serum and pooled 20 HCV patient serum, respectively, by comparing with healthy human serum. In comparison with those profiled by the polyhedral oligomeric silsesquioxane (POSS) material, differential proteins profiled by the SOF material were highly associated with liver diseases through GO analysis and pathway analysis. Furthermore, four common differential proteins profiled by SOF material but not by POSS material were found to be identical and expressed consistently in both pooled serum samples and independent serum samples, which might potentially be biomarkers of HCV infection. Taken together, our study proposes a highly specific protein profiling strategy to display distinctive proteomic profiles, providing a novel idea for drug design and development.

Population pharmacokinetics of ravidasvir in adults with chronic hepatitis C virus infection and impact of antiretroviral treatment.

Ravidasvir (RDV) is a novel NS5A inhibitor that exhibits potent pan-genotypic inhibition of hepatitis C virus (HCV) replication. Sofosbuvir (SOF) plus RDV was demonstrated to be efficacious and safe in adults with active HCV infection, including those living with HIV (LWHIV), in the STORM-C-1 trial. We assessed the population pharmacokinetics (PK) of RDV in a sub-study nested within STORM-C-1 conducted in Thailand and Malaysia. SOF (400 mg) plus RDV (200 mg) was administered orally once daily for 12 weeks to adults with chronic HCV infection, but without cirrhosis and for 24 weeks to those with compensated cirrhosis. Intensive and sparse PK samples were collected at 4, 8, and 12 weeks after treatment initiation. Population PK parameters of RDV and the impact of covariates were evaluated using nonlinear mixed-effects modeling. Five hundred ninety-four participants were included, 235 (40%) had compensated cirrhosis, and 189 (32%) were LWHIV. RDV plasma concentrations were best described by a two-compartment model with first-order elimination. Oral clearance (CL/F) and volume of distribution (Vd/F) parameters were allometrically scaled on fat-free mass. Concomitant antiretroviral treatment (ART) increased RDV CL/F by 30%-60%, with efavirenz-based ART having the largest impact. Females had 16% lower RDV CL/F than males, and higher albumin levels reduced RDV central volume of distribution. While several covariates impact RDV CL/F and Vd/F, the effect on RDV exposures was not clinically relevant based on the efficacy data reported in this diverse Asian adult population. There were no meaningful drug-drug interactions in adults LWHIV on ART.

A Quick and Sensitive LC-MS/MS Method for Simultaneous Quantification of Sofosbuvir Metabolite (GS-331007) in Human Plasma: Application to Hepatitis C Infected Patients with End-Stage Renal Disease.

Sofosbuvir (SOF) is a revolutionary treatment for patients with hepatitis C virus (HCV). However, its efficacy and safety among patients with end-stage renal disease (ESRD) remains controversial. In this study, we examined the levels of SOF metabolite (GS-331007) (SOF-007) in human plasma of patients infected with HCV having ESRD using an optimized liquid chromatography-mass spectrometry (LC-MS) analytical method. In this case-control study, 10 clinically confirmed cases and five controls were enrolled. SOF-007 was extracted from plasma using methanol precipitation. The limit of detection (LOD) for the drug and its metabolite were 0.85 and 2.3, respectively. Such a wide range of quantification in a period of separation time shorter than 3.0 minutes (run time) allowed monitoring of the plasma concentration of analytes up to 4 hours (pre-dialysis and post-dialysis) for 12 weeks in non-cirrhotic patients with HCV infection undergoing dialysis. SOF-007 in the plasma of HCV patients with healthy kidneys showed no cumulative effect. An analysis comparing patients with ESRD and healthy participants showed that their behaviour was similar, followed by dialysis with a relatively small cumulative effect. The plasma concentrations of SOF-007 decreased significantly after the 4-hour period of dialysis compared with the plasma concentrations hemodialysis of pre-dialysis in HCV patients with ESRD.

Quantitative 31P-NMR for Purity Determination of Organophosphorus Compounds (Pharmaceuticals)

Quantitative NMR (qNMR), particularly 1H-qNMR, is useful for determining the absolute purity of organic molecules. However, identifying the target signal(s) for quantification is difficult, because of the overlap and complexity of organic molecules. Therefore, we focused on the 31P nucleus, owing to the simplicity of its signals, and investigated the 31P-qNMR absolute determination method by using organophosphorus drugs, water-soluble cyclophosphamide hydrate (CP), and water-insoluble sofosbuvir (SOF). The optimized and reproducible 31P-qNMR conditions, such as qNMR sample preparation [i.e., selecting suitable deuterated solvents and a reference standard (RS) for 31P-qNMR], hygroscopicity and solution stability of the analyte and RS, and qNMR measurements-such as acquisition time, relaxation delay time, and spectral width-were examined. The CP purities determined using 31P-qNMR agreed well with those for the established 1H-qNMR method in D2O. In contrast, the SOF purity determined using 31P-qNMR was 1.6% higher than that for 1H-qNMR in the protic solvent CD3OD. Therefore, using a protic solvent, such as CD3OD, was not suitable for 31P-qNMR; the deuterium exchange with the RS for 31P-qNMR (i.e., phosphonoacetic acid) resulted in a small integrated intensity. Consequently, the aprotic solvent DMSO-d6 was employed to determine the SOF purity. The data revealed that the SOF purities determined using 31P-qNMR agreed well with the established 1H-qNMR values, indicating that the absolute quantification of SOF using both 31P-qNMR and 1H-qNMR is possible in DMSO-d6. Thus, we established an optimized and reproducible 31P-qNMR method in validation study across multiple laboratories.

Structure-Activity Relationship and Voltage Dependence for the Drug-Drug Interaction between Amiodarone Analogs and MNI-1 at the L-type Cav Channel.

The drug-drug interaction (DDI) between amiodarone (AMIO) and sofosbuvir (SOF), a direct-acting hepatitis-C NS5B nucleotide polymerase inhibitor, has been associated with severe bradyarrhythmia in patients. Recent cryo-EM data has revealed that this DDI occurs at the α-subunit of L-type Cav channels, with AMIO binding at the fenestration site and SOF [or MSD nucleotide inhibitor #1 (MNI-1): analog of SOF] binding at the central cavity of the conductance pathway. In this study, we investigated the DDI between 21 AMIO analogs, including dronedarone (DRON) and MNI-1 (or SOF) in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) and hCav1.2 models. Our findings indicate that among the tested AMIO analogs in hiPSC-CMs at clinically relevant concentrations, only three analogs (AA-9, AA-10, and AA-17) were able to effectively substitute for AMIO in this DDI with 1 µM MNI-1. This highlights the importance of the diethyl amino group of AMIO for interacting with MNI-1. In the hCav1.2 model, desethylamiodarone (AA-12) demonstrated synergy with 90 µM MNI-1, while three other analogs with modifications to the position of the diethyl amino group or removal of iodo groups showed weaker synergy with 90 µM MNI-1. Interestingly, DRON did not exhibit any interaction with 270 µM SOF or 90 µM MNI-1, suggesting that it could safely replace AMIO in patients requiring SOF treatment, other clinically relevant differences considered. Overall, our functional data align with the cryo-EM data, highlighting that this DDI is dependent on the structure of AMIO and cardiomyocyte resting membrane potential. SIGNIFICANCE STATEMENT: Our findings point to specific residues in the AMIO molecule playing a critical role in the DDI between AMIO and MNI-1 (SOF analog), confirming cryo-EM results. Applied at clinically relevant AMIO's concentrations or projected MNI-1's concentrations at the resting potentials mimicking the sinoatrial node, this DDI significantly slowed down or completely inhibited the beating of hiPSC-CMs. Finally, these in vitro results support the safe replacement of AMIO (Cordarone) with DRON (Multaq) for patients requiring SOF treatment, other clinical caveats considered.

Sofosbuvir (+) daclatasvir (+) ribavirin in Egyptian patients with hepatitis C virus: Therapeutic outcomes and the prognostic role of natural killer cells

BackgroundOne of the prominent causes of chronic liver disease worldwide is the hepatitis C virus (HCV). HCV believed that innate immunity contributes to a sustained virological response (SVR) to the treatment of Sofosbuvir (SOF) (+) Daclatasvir (DCV) (+) Ribavirin (RBV). This study aimed to evaluate the impact of SOF (+) DCV (+) RBV therapy and persistent HCV infection on the subset of natural killer cells (NK) in HCV genotype four patients from Egypt. Materials and MethodsOne hundred and ten patients with persistent HCV infections requiring SOF (+) DCV (+) RBV therapy were grouped, and a flow cytometry (FCM) study of the NK cell subset in peripheral blood was performed. The assessment was performed before and after three and/or six months of the cessation of viral suppression therapy when a patient had a long-term viral response (SVR). One hundred and ten volunteers from the National Liver Institute’s (NLI) blood bank were selected as controls. ResultsPatients with chronic HCV infection before therapy had considerably lower CD16+ and CD3− CD56+ cells than controls. Their levels increase during SOF (+) DCV (+) RBV therapy. In patients with SVR during treatment, CD16+ and CD3– CD56+ cells increased significantly compared to those who did not get SVR. Furthermore, CD56+ cells were significantly higher in patients with persistent infection before treatment than controls but diminished with the response to treatment. Conclusion: NK cell activation following SOF (+) DCV (+) RBV therapy and polarization to cytotoxicity occurred early in HCV antiviral therapy and was elevated in the respondents. Our data illustrated that establishing an inhibitory cytotoxic NK profile is related to therapeutic outcomes.

Sofosbuvir Suppresses the Genome Replication of DENV1 in Human Hepatic Huh7 Cells.

Dengue virus (DENV) causes dengue fever and dengue hemorrhagic fever, and DENV infection kills 20,000 people annually worldwide. Therefore, the development of anti-DENV drugs is urgently needed. Sofosbuvir (SOF) is an effective drug for HCV-related diseases, and its triphosphorylated metabolite inhibits viral RNA synthesis by the RNA-dependent RNA polymerase (RdRp) of HCV. (2'R)-2'-Deoxy-2'-fluoro-2'-methyluridine (FMeU) is the dephosphorylated metabolite produced from SOF. The effects of SOF and FMeU on DENV1 replication were analyzed using two DENV1 replicon-based methods that we previously established. First, a replicon-harboring cell assay showed that DENV1 replicon replication in human hepatic Huh7 cells was decreased by SOF but not by FMeU. Second, a transient replicon assay showed that DENV1 replicon replication in Huh7 cells was decreased by SOF; however, in hamster kidney BHK-21 cells, it was not suppressed by SOF. Additionally, the replicon replication in Huh7 and BHK-21 cells was not affected by FMeU. Moreover, we assessed the effects of SOF on infectious DENV1 production. SOF suppressed infectious DENV1 production in Huh7 cells but not in monkey kidney Vero cells. To examine the substrate recognition of the HCV and DENV1 RdRps, the complex conformation of SOF-containing DENV1 RdRp or HCV RdRp was predicted using AlphaFold 2. These results indicate that SOF may be used as a treatment for DENV1 infection.

Diabetic patients with chronic hepatitis C virus response compared to non diabetics when treated with directly acting antiviral therapy

Background and study aimsHepatitis C virus (HCV) impairs glucose homoestasis, thus influences its clinical picture and prognosis.This study aimed at evaluating Diabetes mellitus (DM) on Egyptian patients with chronic hepatitis C (CHC), and its impact on their virologic response when treated with directly acting antiviral (DAA) medications. Patients and methodsAdult patients with CHC were divided into 2 groups; Diabetic patients, and Non diabetic patients serving as control group. All patients were subjected to thorough clinical evaluation, basic biochemical laboratory tests including fasting blood glucose/glycosylated haemoglobin (HbA1C), and virologic assay. They were treated with various combined DAAs, and were monitored during, at and after end of treatment. ResultsDiabetic patients constituted 9.85 % of CHC, and had generally worse laboratory tests (significantly higher transaminases, platelet count, Fib4 and hepatic steatosis) than non diabetic patients, and a less sustained virologic response (SVR) (significantly in Sofosbuvir (SOF) + pegylated interferon (PegIFN) + ribavirin (RBV), SOF + RBV, SOF + daclatasvir (DAC)). Although DM did not play a significant influence on SVR, yet Fib4 and SOF + RBV + PEG-IFN were significant factors affecting SVR among diabetics, while female gender and viraemia were significant factors affecting SVR among non diabetics. Hepatic fibrosis and SOF/RBV significantly influenced SVR in both groups. ConclusionsDiabetic patients with CHC have worse liver biochemical profile, yet DM per se did not influence the virologic response to DAAs, however, some factors played roles in affecting SVR among them.

DEVELOPMENT AND VALIDATION OF A NEW RP-HPLC METHOD FOR SIMULTANEOUS DETERMINATION AND QUANTIFICATION OF SOFOSBUVIR AND DACLATASVIR

Background: Sofosbuvir (SOF) and daclatasvir (DCV) are usually prescribed in combination for the treatment of hepatitis C worldwide. Objectives: In the present study a novel, simple, rapid, and cost-effective reversed-phase high performance liquid chromatography (HPLC) method was developed, optimised, and validated for simultaneous analysis of sofosbuvir and daclatasvir in human plasma as well as in solid dosage forms. Methodology: The chromatographic analyses were carried out using Shimadzu HPLC gradient system (LC20), while the other HPLC system used for the peak purity and repeated validation studies was Agilent 1260 Infinity fitted with diode array detector. The column used was C18 (150 × 4.6 mm; 5 µm), from Agela Technologies. The mobile phase consisted of acetonitrile and 0.02 M potassium Hexafluorophosphate buffer (42:58, v/v) at pH 2.7, pumped at the rate of 1.3 mL min−1. The limit of detection and limit of quantification were determined using dilution method (RSD/m formula). Results: SOF and DCV combination therapy is significant for the treatment of hepatitis C. Development of this RP-HPLC method for the simultaneous determination and quantification of SOF and DCV is a part of an extensive project of novel formulation development (fixed dose combination tablets of SOF and DCV). This method is successfully applied for raw materials as well as in combination tablets. This method may also be applied for the quantification of sofosbuvir and daclatasvir in blood samples of patients taking these two antivirals for hepatitis C treatment. Conclusion: The optimized method was successfully applied for the determination of sofosbuvir and daclatasvir in single run without any interference. Hence, the developed method is quite appropriate for the simultaneous determination of SOF and DCV in solid dosage form as well as in human plasma for clinical research studies.

Identification and characterization of Sofosbuvir-resistant mutations of hepatitis C virus genotype 3a replicon.

Hepatitis C virus (HCV) infection is a major cause of chronic liver disease worldwide. Among its 8 genotypes (GT), GT3 has a relatively lower sustained virological response to highly effective direct-acting antiviral agents (DAA). Sofosbuvir (SOF), an anti-NS5B polymerase inhibitor, is a core component of many anti-HCV DAA cocktail regimens, and its resistant mutations are rare in clinics because these mutations usually severely impair the NS5B polymerase activity, including a mutation S282T in NS5B, the most frequently reported SOF-resistant mutation. In this study, we selected SOF-resistant variants of a previously developed GT3 subgenomic replicon (PR87A7). Two mutations were identified in the viral genome of SOF-resistant PR87A7 variants, Q606R in nontargeted NS3 and S282T in targeted N5SB. We demonstrated that Q606R could rescue the replication defect of S282T in PR87A7, and the resulting double mutant confers the SOF resistance. Finally, we showed that NS3-606R could not compensate for the replication defect of S282T in other GTs. In conclusion, we identified a novel GT3-specific combination of two mutations that confers SOF resistance. Our result calls for attention to potential mutations that may arise in nontargeted viral proteins during the SOF-based DAA treatment of chronic HCV.

Effectiveness of generic sofosbuvir in the treatment of chronic hepatitis C virus infection in Saudi patients.

To assess the effectiveness of generic sofosbuvir (SOF) and branded daclatasvir (DCV) for the treatment of chronic hepatitis C virus (HCV)infected patients. This retrospective study, performed in a single center in Saudi Arabia between August 2017 and July 2022, we enrolled 140 consecutive patients with HCV who received generic SOF and branded DCV. The primary outcome was sustained virologic response at week 12 (SVR12). The majority of the patients were female (62.1%), infected with genotype 4 (57.9%), and treatment-naïve in 120 (85.7%) patients with baseline cirrhosis in 55 (39.3%). The mean patient age was 61±13.6 years. In the intention-to-treat analysis, 131 (93.6%) patients achieved SVR12. Moreover, 85.7%, 100%, 100%, 88.9%, and 96.3% of genotypes 1a, 1b, 2, 3, and 4, respectively, achieved SVR12. In the per-protocol analysis, 131 (96.3%) patients achieved an SVR of 12. Additionally, 92.3%, 100%, 100%, 88.9%, and 98.7% of the patients with genotypes 1a, 1b, 2, 3, and 4, respectively, achieved SVR12. No HCV virologic breakthroughs occurred. In the subgroup analysis, SVR12 rates were comparable regardless of baseline characteristics, such as treatment history, cirrhosis, and hepatocellular carcinoma. Patients achieving SVR12 showed a significant improvement in post-treatment serum liver enzyme and total bilirubin levels. The findings of our study confirm the effectiveness of generic sofosbuvir as a treatment option for HCV infection.