Sofosbuvir Research Articles

Direct-acting antivirals sofosbuvir and daclatasvir attenuate carbon tetrachloride-induced liver fibrosis in mice

Background and aimAdvanced liver fibrosis is a major risk for developing hepatocellular carcinoma (HCC) in chronic hepatitis C virus (HCV) patients. Direct-acting antivirals (DAAs) which are used for treating HCV infection, produce more than 90% cure rate but do not seem to diminish the rate of occurrence or recurrence of HCC. This study aimed to investigate the effect of DAAs sofosbuvir (SOF) and daclatasvir (DAC) on carbon tetrachloride (CCl4)-induced fibrotic changes in mice. MethodsEighty adult male Swiss albino mice were randomly allocated into 8 groups (10 mice/group): normal control group, SOF group (receiving SOF 80 mg/kg body weight (BW), oral gavage, daily), DAC group (receiving DAC 30 mg/kg BW, oral gavage, daily), SOF + DAC group (receiving a combination of both, daily), CCl4 model group (receiving CCl4 2 mL/kg BW, intraperitoneal twice weekly) and three CCl4-intoxicated groups receiving either SOF or DAC or their combination. All CCl4 groups received CCl4 for 12 weeks followed by DAAs for another 12 weeks. ResultsCCl4-induced a significant elevation of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and produced histopathological evidence of fibrosis and liver degeneration along with a significant increase (P ≤ 0.001) of the proliferation markers (proliferating cell nuclear antigen (PCNA) and Ki-67), hepatic stellate cells (HSCs) activation markers (alpha-smooth muscle actin (α-SMA) and glial fibrillary acidic protein (GFAP)), fibrosis marker (matrix metalloproteinase-9 (MMP-9)) and pro-inflammatory cytokine (tumor necrosis factor-alpha (TNF-α)). CCl4-intoxicated mice treated with SOF, DAC, or their combination revealed a significant amelioration (P ≤ 0.001) of CCl4-induced elevation of liver enzymes, fibrotic changes, and liver degeneration along with a significant attenuation (P ≤ 0.001) of CCl4-induced upregulation of all tested markers. The effects of SOF, DAC, and their combination on liver enzymes were comparable while the effect of SOF + DAC combination on mitigating CCl4-induced upregulation of the proliferation and HSCs activation markers was significantly stronger than either SOF or DAC alone. As for MMP-9 and TNF-α, the effects of DAC and SOF + DAC combination were comparable and both were more significant than that of SOF alone. ConclusionsSOF and DAC may possess an antifibrotic effect that is independent of their role as antiviral agents against CCl4-induced liver injury. This might exclude the role of DAAs in early occurrence or accelerated recurrence of HCC through the progression of the HCV patients' pre-existing fibrosis. However, HCC patients treated with DAAs should be closely monitored with continuous HCC surveillance during and post-therapy.

Real-world treatment outcomes of sofosbuvir-based regimens for treatment of chronic hepatitis C with and without human immunodeficiency virus co-infection.

The efficacy of sofosbuvir (SOF)-based regimens in the treatment of chronic hepatitis C (HCV) patients with and without human immunodeficiency virus (HIV) co-infected patients in real-world setting is limited. This was a retrospective cohort study, conducted between 1 January 2017 and 31 December 2021 at Bamrasnaradura Infectious Disease Institute, Thailand. All HCV patients received 12 weeks of SOF-based regimens and had follow-up for at least 12 weeks after therapy discontinuation. The primary outcome was sustained virological response (SVR) at 12 weeks after the end of treatment. Treatment outcomes were compared between HCV patients with and without HIV co-infection. A total of 163 patients were included in the study, 130 (79.8%) were HCV/HIV co-infected, and 33 (20.2%) were HCV mono-infected. Of all, 106 (64%) patients received SOF and ledipasvir. Genotype 1 (GT1) was predominant at 66.4%, followed by GT3 at 22.2%, and GT6 at 11.4%. Overall SVR was 96.9%. SVR in HCV mono-infected was 96.9% and SVR in HIV-HCV co-infected patients was 96.9%. The factor associated with SVR was HCV genotype (P=0.001). Patients with HCV GT6 had lower SVR rates compared with GT1 and GT3 patients (83.3%, 100%, and 97.1% [P=0.000] respectively). There was no association between SVR and other factors such as gender, age, BMI, underlying cirrhosis, baseline HCV viral load, or prior treatment history (all P > 0.05). All patients completed 12-week SOF-based treatment. In real-world setting, HCV treatment with SOF-based regimens between patients with and without HIV co-infection showed high rates of SVR. SOF-based regimens were highly efficacious and tolerated.

Optimization of Fast-dissolving Tablets of Ledipasvirsofosbuvir Inclusion Complexes by Design of Experiments

Abstract: Background: Fast-dissolving tablets (FDTs) were aimed to be developed for the latest approved combination drugs for Hepatitis-C treatment, Ledipasvir (LDV) and sofosbuvir (SBV) which suffered with poor water solubility. Materials and Methods: Cyclodextrin (CD) complexation was done for the drugs to improve their solubility. The optimized CD complexes were taken for developing FDTs to improve dissolution limited bioavailability of these drugs. FDTs were developed by adopting design of experiments approach using Design Expert software. Type of β-CD, type of disintegrant and concentration of disintegrant were taken as the factors. Disintegration time, time for 90% dissolution of LDV and SBV were taken as the responses. The prepared tablets as per the selected experimental design were evaluated for the responses and also other characteristics like tensile strength, packing fraction, wettability. The results were analyzed by ANOVA and numerical optimization was performed with the desirability of minimizing all the responses. Results: All the selected factors were found to influence disintegration and dissolution times significantly. Dimethyl β-CD, croscarmellose sodium at 8% w/w was obtained as the optimized combination of the factors for the FDTs. The FTDs at this optimized combination of the factors were found to have 79.6 sec of DT, 17.72 and 13.68 min. of time for 90% dissolution of LDV and SBV respectively. Conclusion: These results which were significantly much better than those of the marketed tablets indicated that the FTDs were successfully developed using Design of experiments. Keywords: Fast dissolving tablets, Hepatitis-C, Ledipasvir, Sofosbuvir, Optimization.

Electrochemical sensor based on bio-inspired molecularly imprinted polymer for sofosbuvir detection.

The electropolymerized molecularly imprinted polymers (MIP) have enabled the utilization of various functional monomers with superior selective recognition of the target analyte template. Methyldopa is an attractive synthetic dopamine analogue which has phenolic, carboxylic, and aminic functional groups. In this research, methyldopa was exploited to fabricate selective MIPs, for the detection of sofosbuvir (SFB), by a simple electropolymerization step onto a disposable pencil graphite electrode (PGE) substrate. The interaction between methyldopa, as a functional monomer, and a template has been investigated experimentally by UV spectroscopy. A polymethyldopa (PMD) polymer was electrografted onto PGE in the presence of SFB as a template. X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (ESI), and cyclic voltammetry (CV) were used for the characterization of the fabricated sensor. Differential pulse voltammetry (DPV) of a ferrocyanide/ferricyanide redox probe was employed to indirectly detect the SFB binding to the MIP cavities. The sensor shows a reproducible and linear response over a dynamic linear range from 1.0 × 10-11 M to 1.0 × 10-13 M of SFB with a limit of detection of 3.1 × 10-14 M. The sensor showed high selectivity for the target drug over structurally similar and co-administered interfering drugs, and this enabled its application to detect SFB in its pharmaceutical dosage form and in spiked human plasma samples.

Effect of SOF/VEL Antiviral Therapy for HCV Treatment

Liver cirrhosis and hepatocellular carcinoma disease caused by the Hepatitis C virus (HCV) infection. Inside this article, a deterministic model has been formulated and analyzed for the transmission of HCV in the liver cells. We have also considered two types of viral strain (wild and mutant).  We have also projected a mathematical model of the effect of Sofosbuvir  (SOF) together with Velpatasvir (VEL) antiviral therapy in HCV infected patients. Our analytical and numerical findings reveal that the optimal schedule of treatment for the best result should be obtained by choosing the best strategy depending on the circumstances.

Selective profiling of liver-related specific proteins based on sofosbuvir-modified magnetic separation material.

It has great significance in profiling specific proteins throughout for better understanding of complex pathological processes and in-depth pharmacological studies. In this work, an efficient protein profiling strategy was developed based on the specific protein-drug interaction. Sofosbuvir (SOF), as a first-line drug for the treatment of hepatitis C, was modified onto the surface of nanoparticles through stable chemical bonds to fabricate a novel magnetic separation material denoted as Fe3O4@SiO2@PAA@SOF. With sequence coverage as the screening parameter, nine proteins were profiled from fetal bovine serum (FBS) of which eight were liver related. Similarly, the strategy was applied to hepatocellular carcinoma (HCC) patient serum. Eight proteins were profiled and all of them were liver related, demonstrating the superb specificity and selectivity of this strategy for profiling liver-related proteins by virtue of protein-SOF interaction. When serum proteins from HCC patients were compared to those from healthy people, one unique differential protein (D3DQX7) was profiled, which was liver related and was a potential target for ameliorating liver diseases. For further research, this material design concept and protein profiling strategy can be extended to employ other drugs for corresponding studies. Sofosbuvir, as a therapeutic drug for liver diseases, was modified onto the surface of magnetic nanoparticles to fabricate the specific selective separation material (Fe3O4@SiO2@PAA@SOF). Based on protein-SOF interaction, the material was applied to adsorb specific proteins from different serum samples. After MS analysis, specific proteins, most of which were liver related, were successfully profiled from FBS and HCC patient serum, fully demonstrating the superb specificity and selectivity of this protein profiling strategy.

Green RP-HPLC method for simultaneous determination of sofosbuvir, ledipasvir, velpatasvir antivirals and beyond in their bulk material and co-formulated products

In the present era, pharmaceutical industry is floated with the development of novel antiviral medications either in single or co-formulated pills. This growth of antiviral drug market is gaining the interest due to economic and therapeutic policies. Therefore, it is a real demand to validate analytical methods that monitor the entire standards considering their quality, safety and efficacy with maximum accuracy and maximum time and cost efficiency.HPLC offers a quick, automated, and highly accurate method to identify certain chemical components in a sample. Medical, forensic, bioavailability, environmental and manufacturing labs use the technique to quantify and separate the chemicals in a multicomponent sample. Consequently, an HPLC method is developed for quantitative analysis of a mixture containing five anti-viral agents namely, sofosbuvir (SF), ledipasvir (LD), velpatasvir (VL), daclatasvir (DC), and valacyclovir (VC) The method based on partitioning between reversed phase and methanol/water mobile phase with gradient elution at 1 mL/min flow rate and UV detection at 260 and 330 nm wavelengths along linear concentration ranges 5.00–80.00, 2.00–50.00, 5.00–50.00, 2.00–80.00 and 5.00–45.00 µg/ mL for SF, LD, VL, DC and VC, respectively.The greenness profile was assessed using Analytical Eco-scale and GAPI tools and found to be in agreement with the green analytical chemistry principles. The proposed method was validated experimentally and statistically and found to be a viable choice for single and multicomponent analysis in multi-tasks laboratory that consider the environmental impact and quality-cost balance with precision RSD% <2.00 % and accuracy ranging from 99.79 to 100.90 %.

The ameliorating role of sofosbuvir and daclatasvir on thioacetamide-induced kidney injury in adult albino rats.

Thioacetamide (TAA) exposure and hepatitis C virus infection are usually associated with renal dysfunction. Sofosbuvir (SFV) and daclatasvir (DAC) drugs combination has great value in the treatment of hepatitis C. The study aimed to identify the nephrotoxic effects of TAA and to evaluate the ameliorative role of SFV and DAC in this condition. Forty-eight adult male albino rats were divided into eight groups and received saline (control), SFV, DAC, SFV+DAC, TAA, TAA+SFV, TAA+DAC and TAA+SFV+DAC for eight weeks. Kidney and blood samples were retrieved and processed for histological (Hematoxylin and Eosin and Masson's trichrome), immunohistochemical (α-smooth muscle actin), and biochemical analysis (urea, creatinine, total protein, albumin, malondialdehyde, reduced glutathione, superoxide dismutase, and tumor necrosis factor-α). Examination revealed marked destruction of renal tubules on exposure to TAA with either hypertrophy or atrophy of glomeruli, increase in collagen deposition, and wide expression of α-smooth muscle actin. Also, significant disturbance in kidney functions, oxidative stress markers, and tumor necrosis factor-α. Supplementation with either SFV or DAC produced mild improvement in the tissue and laboratory markers. Moreover, the combination of both drugs greatly refined the pathology induced by TAA at the cellular and laboratory levels. However, there are still significant differences when compared to the control. In conclusion, SFV and DAC combination partially but greatly ameliorated the renal damage induced by TAA which might be enhanced with further supplementations to give new hope for those with nephropathy associated with hepatitis.

Real World Efficacy and Safety of Sofosbuvir + Velpatasvir + Voxilaprevir in Romanian Patients with Genotype 1b HCV Infection Non-reponders to DAAs Therapy

The sofosbuvir (SOF) / velpatasvir (VEL) / voxilaprevir (VOX) combination has been evaluated in more than 800 patients enrolled in phase II and phase III studies, where it demonstrated excellent safety and efficacy, achieving overall sustained viral response (SVR) rates of more than 95%. We aimed to assess the efficacy and safety of SOF/VEL/VOX in a real-world study, including patients previously treated for genotype 1b hepatitis C virus (HCV) infection that did not obtain a sustained viral response with previous direct-acting antivirals (DAAs) therapy. In Romania, through a nationwide government-funded program in 2019-2020, 213 patients with chronic hepatitis C non-responders to previous DAAs therapy, received treatment with SOF/VEL/ VOX 400/100/100 mg/day for 12 weeks. We performed a retrospective longitudinal study that included 143 individuals who were treated in Bucharest, Iași, Craiova and Constanța clinics, all with genotype 1b HCV infection. Efficacy was assessed by the percentage of patients achieving SVR 12 weeks post-treatment (SVR12). Serious adverse events (SAE) were registered. Our cohort comprised 53% males with a median age of 60 years (27÷77); 47% were pre-treated with ombitasvir/paritaprevir/ritonavir+dasabuvir ± ribavirin, 40% with ledipasvir/SOF, 13% with elbasvir/ grazoprevir. 42% of patients associated co-morbidities, 45% had compensated liver cirrhosis, 2% had treated hepatocellular carcinoma (HCC) and 1% had hepatitis B virus co-infection. SVR by intention to treat was reported in 139/143 (97.2%) and per protocol in 141/143 (98.6%). No predictive factors for SVR were identified. Rate of liver decompensation in patients with cirrhosis was 6% and was statistically associated in multivariate analysis with Child-Pugh score (p<0.01) and with severe steatosis (p=0.004). Occurrence of new HCC was reported in 3.6% of all patients with cirrhosis and was associated with poor liver function [higher Child-Pugh score (p=0.001) and low albumin levels (p=0.02)]. Serious adverse events related to therapy were reported in 1/143(0.7%). SOF/VEL/VOX was highly efficient in our population of patients with a 97.2% SVR. Liver decompensation occurred in 6% of cirrhotic patients at SVR, related to hepatic dysfunction.

Eco friendly stability indicating HPTLC method for simultaneous determination of sofosbuvir and ledipasvir in pharmaceutical tablets and HPTLC-MS characterization of their degradation products

Recently, the analytical community has shown increasing interest in developing more environment-friendly practices by eliminating or reducing the use of hazardous chemicals and solvents which are extremely dangerous to human health and the environment. Thus in this study, a simple, rapid, inexpensive and eco-friendly HPTLC method with densitometric detection was designed, optimized and validated for the simultaneous quantitation of the antiviral drugs sofosbuvir (SOF) and ledipasvir (LED) in pure powder, synthetic mixtures, combined pharmaceutical formulation and in the presence of their stressed degradation products with high sensitivity and no interference. The separation was carried out on silica gel F254 plates, using green mobile phase ethyl acetate: water: ethanol (94:5:1v/v/v) for development followed by densitometric detection of SOF and LED at 250 and 320 nm, respectively. Both drugs had second order polynomial calibration curves within ranges 100–5000 ng/spot and 100–3000 ng/spot for SOF and LED, respectively, with correlation coefficients >0.9998 and the limits of detection were 30 and 29 ng/spot and the limits of quantification were 90 and 88 ng/spot for SOF and LED, respectively. The method was validated in terms of linearity, accuracy, precision, selectivity, and robustness. The drugs were subjected to acidic and basic hydrolysis, oxidation and photolytic conditions as per ICH guidelines, followed by detection of the degradation products and structure elucidation of their fragments with the aid of the HPTLC-ESI- MS technique. The greenness of the proposed method was assessed using the analytical Eco-Scale as an assessment tool with a 93-point score. So, it is considered excellent green.

Quantitative 31P-NMR for Purity Determination of Sofosbuvir and Method Validation.

Quantitative 1H-NMR (1H-qNMR) is useful for determining the absolute purity of organic molecules; however, it is sometimes difficult to identify the target signal(s) for quantitation because of their overlap and complexity. Therefore, we focused on the 31P nucleus because of the simplicity of its signals and previously reported 31P-qNMR in D2O. Here we report 31P-qNMR of an organophosphorus compound, sofosbuvir (SOF), which is soluble in organic solvents. Phosphonoacetic acid (PAA) and 1,4-bis(trimethylsilyl)benzene-d4 (1,4-BTMSB-d4) were used as reference standards for 31P-qNMR and 1H-qNMR, respectively, in methanol-d4. The purity of SOF determined by 31P-qNMR was 100.63 ± 0.95%, whereas that determined by 1H-qNMR was 99.07 ± 0.50%. The average half bandwidths of the 31P signal of PAA and SOF were 3.38 ± 2.39 and 2.22 ± 0.19 Hz, respectively, suggesting that the T2 relaxation time of the PAA signal was shorter than that of SOF and varied among test laboratories. This difference most likely arose from the instability in the chemical shift due to the deuterium exchange of the acidic protons of PAA, which decreased the integrated intensity of the PAA signal. Next, an aprotic solvent, dimethyl sulfoxide-d6 (DMSO-d6), was used as the dissolving solvent with PAA and sodium 4,4-dimethyl-4-silapentanesulfonate-d6 (DSS-d6) as reference standards for 31P-qNMR and 1H-qNMR, respectively. SOF purities determined by 31P-qNMR and 1H-qNMR were 99.10 ± 0.30 and 99.44 ± 0.29%, respectively. SOF purities determined by 31P-qNMR agreed with the established 1H-qNMR values, suggesting that an aprotic solvent is preferable for 31P-qNMR because it is unnecessary to consider the effect of deuterium exchange.

Clinical and economic value of sofosbuvir-based regimens in the treatment of chronic hepatitis C in Spain.

The treatment of chronic hepatitis C virus (HCV) with direct-acting antivirals has undergone a spectacular revolution and added significant value to healthcare systems and patients. The aim of the study was to evaluate the efficiency and value of Sofosbuvir (SOF)-based regimens for a target population of 85,959 chronic HCV patients treated in Spain during 2015-2019, compared to previous therapeutic strategies (peginterferon/ and ribavirin in double/triple therapy with telaprevir or boceprevir). A previously developed lifetime Markov model was adapted to simulate the disease HCV evolution. In SOF-based regimens, all patients (100%) were treated regardless with sustained virological response (SVR) of 93-98%, obtained from real-world data. In previous therapeutic, only ≥F2 patients were treated according to clinical practice (38%) with an average SVR of 61% taken from published literature. The value was measured as clinical and economic impact in terms of avoided HCV-related mortality and liver complications; total costs and quality-adjusted life years (QALYs) applying an annual 3% discount rate. Compared to previous therapeutic, during lifetime, SOF-based regimens reduced decompensated cirrhosis by 89%, hepatocellular carcinoma by 77% and liver transplant by 84%, decreasing the cost associated to liver complications management in €770 million. SOF-based regimens also decreased liver-related mortality by 82%. Besides, SOF-based regimens gained 310,765/QALYs, saving €274 million (considering drugs, monitoring, and HCV management). For Spain, SOF-based regimens offer value for HCV patients in terms of lowering HCV-related liver disease burden and generating significant cost savings for the health system, contributing to the WHO goal.

Daclatasvir as a hepatitis C infection treatment option: an up-to-date evaluation

ABSTRACT Introduction Globally, it is estimated that 290,000 patients infected with hepatitis C virus (HCV) died from hepatitis C consequences, including cirrhosis and hepatocellular carcinoma in 2019. Although daclatasvir (DCV), combined with sofosbuvir (SOF), is effective in HCV patients, the new pan-genotypic combinations are considered by many as more cost-effective and successful in eradicating HCV infection. Areas covered This review discusses the safety, efficacy, and cost-effectiveness of DCV as an HCV treatment option based on real-world studies and pharmacoeconomic evaluations. Expert opinion Real-life studies suggest that SOF/DCV has acceptable sustained virological response and can be used successfully to manage HCV. Nonetheless, the use of SOF/DCV is limited by the longer treatment duration in genotype (GT)-3 patients and the need for ribavirin (RBV) in treatment-experienced patients which increases the likelihood of adverse effects. DCV is likely to remain as a therapeutic option for the management of GT-1, GT-2, and GT-4 patients in resource limited settings, while GT-3 patients are more likely to benefit from RBV-free direct-acting antiviral combinations such as SOF/velpatasvir for 12 weeks or glecaprevir/pibrentasvir for 8 weeks. The introduction of generics for these new pan-genotypic drugs would likely eliminate the need for SOF/DCV in the near future.

Treatment outcomes and costs of a simplified antiretroviral treatment strategy for hepatitis C among Hepatitis C Virus and Human Immuno deficiency Virus co-infected patients in Ukraine.

To demonstrate the use of a standard dose of ledipasvir (LDV) and sofosbuvir (SOF), with or without ribavirin, to treat hepatitis C and hepatitis C/HIV co-infection in Ukraine. Eligible HCV viraemic adults from two clinics in Kyiv were treated with LDV/SOF with or without weight-based ribavirin for 12 weeks. Clinical assessments were performed at screening and at week 24, and as needed; treatment was dispensed every 4 weeks. The primary outcome was sustained virologic response (SVR) 12 weeks after treatment, with analysis by intention to treat. Cost per patient was estimated in USD (2018) over the 24-week period. Of 868 patients included in the study and initiated on therapy, 482 (55.5%) were co-infected with HIV. The common genotypes were 1 (74.1%) and 3 (22%). Overall, SVR was achieved in 831 of the 868 patients (95.7%). SVR in patients with hepatitis C alone and hepatitis C/HIV co-infection was 98.4% and 93.6%, respectively. Adverse events were infrequent and usually mild. Using generic medication, cost per patient was estimated at US$680. A standard dose of LDV and SOF, with ribavirin as per protocol, resulted in good outcomes for patients with both hepatitis C alone and co-infected with hepatitis C/HIV. Program costs in Ukraine were modest using generic medication.

Selection dynamics of HCV genotype 3 resistance-associated substitutions under direct-acting antiviral therapy pressure.

The chronic hepatitis C (CHC) treatment is currently based on the use of direct-acting antivirals (DAAs), and patients infected with hepatitis C virus genotype 3 (GT3) have emerged as a more difficult-to-cure population. The NS5A inhibitor daclatasvir (DCV) and sofosbuvir (SOF), an NS5B viral polymerase inhibitor, are among the drugs that compose more effective and safer treatment regimens. The virus genetic variability is related to resistance-associated substitutions (RASs) that adversely impact DAAs effectiveness. The aims of this study were to analyze the association of NS5A and NS5B RASs and other clinical factors with DAAs regimens effectiveness in patients with GT3 CHC infection. This was a prospective cohort study performed in a Brazilian university hospital. Individuals older than 18 years with GT3 CHC treated with SOF+DCV ± ribavirin (RBV) or SOF+peginterferon (PEG)+RBV were included. Blood samples were collected at baseline and post-treatment. A total of 121 patients were included. Sustained virological response rates were 87.6% for the SOF+DCV ± RBV group and 80.0% for the SOF+PEG+RBV arm. Cirrhosis, prior treatment with interferon/PEG+RBV, and baseline NS5A RAS were associated with higher risk of treatment failure. The NS5A analysis suggested that A30K, Y93H, and RAS at site 62 were related to failure. Interestingly, a likely compensatory effect was shown between A30K and A62T. Emergence of Y93H was always associated with RAS at position 62. The RASs dynamics comprehension is an important tool to indicate more effective treatment for GT3 patients.

Identification of NS5B resistance against SOFOSBUVIR in hepatitis C virus genotype 3a, naive and treated patients.

Pakistan has the second highest prevalence of HCV with genotype 3a (GT-3a) being the most frequently circulating genotype. Currently, resistance-associated substitutions (RASs) are a major challenge in HCV treatment with direct-acting antivirals (DAAs). Sofosbuvir (SOF) is an FDA-approved NS5B nucleotide inhibitor. The aim of this study was to identify these RASs in the NS5B gene in naive and treated Pakistani HCV 3a isolates against SOF. Blood samples were collected from anti-HCV-positive patients, followed by HCV RNA isolation and real-time PCR quantification. HCV-positive patients were processed for HCV RNA genotyping, patients with genotype 3a were processed for NS5B gene amplification and sequencing. GT-3a was the most prevalent genotype (62.2%). S282T was identified in 2 (8.7%) patients, C316Y/G/R in 3 (13%), V321A and L320P in 1 (4.3%) each in SOF/RBV-resistant patients. Variants of S282 were detected in 3 (13%) of SOF/RBV-treated patients. While INF/RBV-associated mutations were also analysed, D244N, A333R and A334E were identified in 2 (9.5%), 3 (14.2%) and 7 (33.3%) in treatment-naive and 15 (65.2%), 7 (30.4%) and 5 (21.7%) treated patients, respectively. Q309R was observed only in one treatment-experienced patients. Some substitutions were present at higher frequency in both groups like N307G, K304R, A272D and R345H, considered that they do not have any role in sofosbuvir resistance. It was concluded that sofosbuvir RASs are present in Pakistani HCV GT-3a isolates, and they should be monitored carefully, especially in treatment-experienced patients, for further selection of treatment regimens. HCV RASs have been studied very well across the world but there is scarcity of data regarding this topic in Pakistani population, this study provides data regarding the prevalence of these RASs in Pakistani HCV isolates emphasizing the fact that these RASs must be carefully monitored before starting HCV treatment, especially in treatment failure patients.

S3264 A Hepatitis C (HCV) Infection Treatment Dilemma

Introduction: HIV/HCV coinfection increases liver-related morbidity and mortality. This special population should be prioritized for treatment. Currently available direct-acting antivirals (DAAs) are safe and effective, but there are many drug interactions (DIs) to consider. Carbamazepine (CBZ) is contraindicated with all available DAAs. Patients that require treatment for HCV but cannot stop CBZ do not have a clear treatment option. Patients may be transitioned to newer antiepileptics that do not have the same contraindications, but some patients are unwilling or unable to change medications. Case Description/Methods: Patient is a 59-year-old man with well-controlled HIV on HAART, well-controlled trigeminal neuralgia on CBZ, anemia, and non-cirrhotic (FibroScan 12 kPa), treatment naïve, chronic HCV genotype 1a. Due to DIs between DAAs and CBZ, multiple attempts were made to discontinue CBZ but were unsuccessful. Neurosurgery offered surgical gamma knife management, but up to 40% of patients still require CBZ post-procedure. An initial plan for daclatasvir (DAC)-sofosbuvir (SOF)-ribavirin (RBV) was proposed, but DAC is no longer available in the US. Patient was followed conservatively but developed thrombocytopenia and progression of fibrosis (FibroScan 14.7kPa). Given worsening liver condition, shared decision-making was performed, and patient completed 16 weeks of Glecaprevir (GLE)/pibrentasvir (PIB) + SOF 400mg with 4 weeks of ezetimibe 10mg stopping when the viral load was undetectable. Patient was instructed to start the ezetimibe with the GLE/PIB + SOF but was hesitant to take it due to adverse reaction to statins in the past. At 4 weeks of treatment, HCV viral load was still detectable. Patient was re-educated on the purpose of the ezetimibe and reassured it was not a statin. He took it from week 4-8 of treatment. At week 8, HCV viral load was undetectable. Patient achieved SVR 12 and showed improvement of his FibroScan score to 9.6 kPa. Discussion: GLE/PIB is pangenotypic, has a high barrier to resistance, and has been proven safe and effective in combination with SOF + RBV in MAGELLAN 3 for 16 weeks duration. Patient has history of anemia, making RBV undesirable. Ezetimibe blocks the NPC1L receptor which potentially inhibits HCV entry into the hepatocyte. HCV relies on cell-to-cell transmission, so we chose to add ezetimibe 10mg daily until HCV not detected. There is a need for larger studies to determine the applicability of this case study to other patients.

Changes in renal function in patients with chronic hepatitis C treated with sofosbuvir‐velpatasvir

AbstractDirect‐acting antivirals (DAAs) have become an effective first‐line treatment for chronic hepatitis C (CHC), and the fixed‐dose combination of sofosbuvir (SOF) and velpatasvir (VEL) is one of the most important pangenotypic DAA regimen according to present treatment guideline. The association between SOF‐based regimens and renal toxicity remains controversial. A total of 953 patients including 130 with estimated glomerular filtration rate (eGFR) ≤ 60 mL/min/1.73m2 and 823 with eGFR &gt; 60 mL/min/1.73m2 receiving SOF/VEL therapy for 12 weeks were enrolled in this study. The eGFR was assessed at baseline, end of treatment (EOT), and 12 weeks after completion of the therapy (end of follow‐up, EOF). The eGFR in patients with eGFR ≤ 60 mL/min/1.73m2 increased from baseline (47.89 ± 10.25 mL/min/1.73m2) to EOT (51.65 ± 15.92; P &lt; .001) and EOF (51.51 ± 14.46 mL/min/1.73m2; P &lt; .05). The eGFR in patients with eGFR &gt; 60 mL/min/1.73m2 at baseline (91.52 ± 22.06 mL/min/1.73m2) was lower at EOT (90.37 ± 22.3; P &lt; .05), with no difference between EOT and EOF (P = .06). Multivariable analysis showed that a higher serum albumin level was associated with a lower risk of eGFR decrease at EOT, and the patients with baseline eGFR &gt; 60 mL/min/1.73m2 were associated with a higher risk of eGFR decrease at EOF. The rates of sustained virologic response 12 weeks after treatment cessation (SVR12) were 99.2% in per‐protocol analysis, and the most common adverse events were fatigue (4.7%), abdominal discomfort (4.5%), and skin itching (3.7%). In conclusion, renal function improved after the SOF/VEL treatment in patients with CHC and chronic kidney disease. Thus, SOF/VEL was safe, effective, and tolerable in these patients.

Detection of Occult Hepatitis C Virus Infection in Egyptian Patients Who Achieved a Sustained Virologic Response to Direct-Acting Antiviral Agents.

Occult hepatitis C virus (HCV) infection (OCI) is diagnosed based on the detection of HCV-RNA in non-serum reservoirs, such as peripheral blood mononuclear cells (PBMCs) and/or hepatocytes with undetectable HCV-RNA in the serum. The current study was designed to shed more light on the presence of occult HCV in a population of cases who achieved an SVR after receiving treatments for HCV-infection and its significance. This cross-sectional study evaluated 111 chronic HCV patients treated at Theodor Bilharz Research Institute, Egypt and achieved a sustained virological response (SVR) 12 -24 weeks after treatment with Direct acting antiviral drugs (DAAs). The treatment lasted 12 or 24 weeks using generic medications including Sofosbuvir (SOF) 400 mg/day and Daclatasvir (DCV) 60 mg/day ± weight-based Ribavirin (RBV) 600-1000 mg/day. After achieving the SVR 12 -24 weeks, all patients were subjected to clinical examination and full laboratory investigations. All the candidates were assessed for fibrosis pre/post-treatment by transient elastography (Fibroscan©). Eighty-seven patients (78.4%) received dual therapy (SOF/DCV) and 24 patients (21.6%) received triple therapy (SOF/DCV/RBV). One hundred and seven patients received the regimen for 12 weeks (96.4%) and only four patients received the regimen for 24 weeks (3.6%). All patients were examined in terms of HCV RNA in plasma and PBMCs. Nine patients (8.1%) were positive for PBMCs HCV RNA. The presence of Occult HCV infection (OCI) was significantly correlated with age, level of AFP, and the degree of liver stiffness. The OCI was present in 8.1% of the patients who achieved an SVR 12 - 24 weeks. These patients were mostly aged and with elevated AFP and advanced fibrosis. Monitoring and follow-up of those patients may help to assess the outcomes.

Dual versus triple therapy in treatment of hepatitis C virus (HCV)

BackgroundThe goal of HCV treatment is eradication of the virus to prevent complications associated with the disease and decrease all-cause mortality. This work compared sustained viral response (SVR) 12 weeks after end of treatment of chronic HCV patients with different treatment regimens, namely 4 regimens. Two hundred treatment naive chronic HCV patients were selected and divided into 4 equal groups as follows: group A received pegylated interferon (peg IFN) and ribavirin (RBV); group B received peg IFN, RBV, and sofosbuvir (SOF); group C received RBV and SOF; group D received SOF, daclatasvir (DCV), and RBV.ResultsThe sustained viral response after 12 months of treatment is 57.23%, 72.09%, 64.40%, and 96.42% of patients in groups A, B, C, and D, respectively. Hence, group D regimen showed the best results.ConclusionSOF and DCV and RBV have the highest SVR12 and least side effects compared to other treatment regimens. Although group D patients initially had poor pretreatment investigations relative to other groups, they proved to have the highest tolerability to this regimen. Such findings hold promising line of treatment and better prognosis even for chronic HCV patients with poor liver condition.