Validated LC/MS method for simultaneous determination of elbasvir and grazoprevir in human plasma.

A sensitive and accurate LC/MS method for the determination of elbasvir (ELB) and grazoprevir (GZP) in human plasma was established using daclatasvir (DCT) as an internal standard. The analytes were separated on a Waters Spherisorb phenyl column (150mm×4.6mm ID, 5µm particle size) maintained at 40°C±2°C. Gradient elution, at a flow rate of 0.8mLmin-1, was used. The mobile phase consists of 90% of acetonitrile mixed to 10% of a 5mM ammonium formate buffer (+0.1% v/v of trimethylamine, pH was adjusted to 3.2 by formic acid) as phase A and 10% of acetonitrile mixed to 90% of the same buffer as phase B. Liquid-liquid extraction with ethyl acetate solvent was used to recuperate compounds from plasma. The method was validated over a concentration range of 2 and 100ng/mL for GZP and between 1 and 50ng/mL for ELB. The intra- and inter-day precision and accuracy of the quality control samples at low, medium, and high concentration levels exhibited relative standard deviations (RSD)<15%, and the accuracy values ranged from 94.2 to 107.8%. The robustness of the method was established using a two-level full factorial design.

Safety and efficacy of elbasvir/grazoprevir in patients infected with hepatitis C virus genotype 4 in Qassim region of Saudi Arabia.

Objective: Untreated hepatitis C virus (HCV) infection can lead to cirrhosis, hepatocellular cancer, and even death and also increases liver diseases. The elbasvir/grazoprevir (EBR-GZR) treatment regimen when given in HCV genotype (GT) 1 and GT4 infection for 8 or 12 weeks showed a high sustained virolgical response (SVR) rates in different populations. This study was assessed the effectiveness as well as safety of EBR-GZR in 12 week treatment regimen in HCV GT4-infected treatment-naïve Saudi patients. Methods: This study conducted from June 2017 and December 2020 on Saudi HCV patients infected with GT4. Treatment protocol was given for 12 weeks in treatment-naive HCV GT4 infected cirrhotic and non-cirrhotic participants which were later followed for a total of 24 weeks for safety and efficacy of EBR-GZR. Results: We analyzed data of 54 participants with HCV GT 4 infection. Mean age was (53.46 ± 14.94) Treatment regimen was given to 14 cirrhotic (F4) and 40 non-cirrhotic (F0-F3). SVR was seen in 98.1% of participants with tolerable side effects and improved model for end stage liver disease (MELD) scores as fall in percentage seen from 18.5% to 14.8% in participants with MELD > 10. Conclusion: This retrospective study confirms that EBR-GZR for 12 weeks is a safe and effective treatment regimen in HCV GT4 patients in studied Saudi population. Treatment completion was followed by high SVR12 rates with improvement in prognostic markers of liver disease in participants with compensated cirrhosis. In short, the EBR-GZR combination showed efficacy in achieving the SVR12 in Child-Pugh B cirrhotic and non-cirrhotic population with a favorable safety profile.

Elucidating the role of N440K mutation in SARS-CoV-2 spike - ACE-2 binding affinity and COVID-19 severity by virtual screening, molecular docking and dynamics approach.

COVID-19 has become a public health concern around the world. The frequency of N440K variant was higher during the second wave in South India. The mutation was observed in the Receptor Binding Domain region (RBD) of the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) spike (S) protein. The binding affinity of SARS-CoV-2-Angiotensin-Converting Enzyme-2 (ACE-2) plays a major role in the transmission and severity of the disease. To understand the binding affinity of the wild and mutant SARS-CoV-2 S with ACE2, molecular modeling studies were carried out. We discovered that the wild SARS-CoV-2 S RBD-ACE-2 complex has a high binding affinity and stability than that of the mutant. The N440K strain escapes from antibody neutralization, which might increase reinfection and decrease vaccine efficiency. To find a potential inhibitor against mutant N440K SARS-CoV-2, a virtual screening process was carried out and found ZINC169293961, ZINC409421825 and ZINC22060839 as the best binding energy compounds. Communicated by Ramaswamy H. Sarma.

An observational, prospective, multicenter study on the utilization and effectiveness of elbasvir-grazoprevir treatment association for chronic hepatitis C in France (ZEPHYR study).

Background and Aim: The efficacy and safety profiles of elbasvir-grazoprevir (EBR/GZR) has been established in more than 10 clinical trials. However, the characteristics of patients treated in routine clinical practice may differ. The present study was therefore designed to assess the real-life effectiveness of EBR/GZR therapy in the general population and among subgroups with a high hepatitis C virus (HCV) prevalence in France. Methods: The Zephyr study was designed as a French, multicentre, prospective, observational study on EBR/GZR use and effectiveness in current practice in chronic hepatitis C patients. These results are based on data regarding the adult patients who received at least one dose of EBR/GZR between December 2017 and June 2019 in 67 French hospitals and clinics. Results: Overall, 478 patients were included. The Full Analysis Set corresponded to the 467 patients who met all the inclusion criteria and none of the exclusion criteria. Gender was balanced and the mean age was 55.7 ± 13.3 years. The patients were mainly treatment-naive (89.5%) and infected with Genotype 1b (70.4%). Among the 75 patients with HCV Gt1a genotype, 56% had HCV RNA ≥ 800,000 IU/ml. F3-F4 fibrosis stage involved 24.2% of our population. Our subgroups were distributed among 110 migrants (23.6%), 58 (15.3%) using opioid agonist treatment, including people who inject drugs, 30 (6.8%) with chronic kidney disease Stages 3-5, 9 (1.9%) with an inherited blood disorder, and 4 (0.9%) coinfected with HIV. The remaining 269 (58.7%) were included in the general population subgroup. Overall, sustained virologic response 12 weeks after the end of treatment reached 98.0% and remained consistent among genotype, HCV RNA values, fibrosis stage, and the subgroup of interest. The rate of Alcohol Use Disorders Identification Test-Consumption​​​ and Life Habit questionnaire completion was high at each visit, with data suggesting alcohol consumption decrease and an improvement in quality of life. Conclusions: Using real-world evidence data on a French population representative of HCV patients, we confirmed the results obtained during EBR/GZR development program.

High real-world effectiveness of 12-week elbasvir/grazoprevir without resistance testing in the treatment of patients with HCV genotype 1a infection in Norway.

BACKGROUND AND AIMS: The recommended treatment duration of hepatitis C virus (HCV) genotype 1a (GT1a) infection with elbasvir/grazoprevir (EBR/GZR) in the presence of a high baseline viral load and resistance associated substitutions (RAS) is 16 weeks with ribavirin added. The objective of this study was to evaluate the real-world effectiveness of 12 weeks of EBR/GZR without ribavirin and regardless of baseline viral load and RAS testing. METHOD: This retrospective, observational cohort study was performed at five Norwegian hospitals that did not systematically utilize RAS testing. All adult patients with chronic HCV GT1a and compensated liver disease who had received 12 weeks of EBR/GZR without ribavirin and baseline RAS testing, were included. The primary endpoint was sustained virologic response at week 12 (SVR12), or if not available, at week 4 (SVR4). RESULTS: We included 433 patients and attained SVR data on 388. The mean age was 45.7 years (22-73 years). 67.2% were male. HIV co-infection was present in 3.8% (16/424) and cirrhosis in 4% (17/424). The viral load was >800 000 IU/mL in 55.0% (235/427) of patients. Overall SVR was achieved in 97.2% (377/388). SVR was achieved in 98.3% (169/172) of those with viral load ≤800 000 IU/mL and in 96.2% (202/210) of those with viral load >800 000 IU/mL. CONCLUSION: We observed high SVR rates among patients with HCV GT1a infection treated with EBR/GZR for 12 weeks without ribavirin, with no regard to baseline viral load and no RAS testing.

Efficacy and safety of elbasvir/grazoprevir treatment for Chinese patients with hepatitis C virus genotype 1b: a retrospective study.

OBJECTIVES: To determine the efficacy and safety of elbasvir/grazoprevir (EBR/GZR) treatment in Chinese patients with GT1b chronic hepatitis virus C (HCV) infections. METHODS: In this retrospective study, 49 treatment-naive patients with chronic GT1b HCV infection were treated with GZR (100 mg) plus EBR (50 mg) for 12 weeks. The viral response was the primary endpoint and fibrosis stage changes during and after treatment, as well as the incidence of treatment-emergent adverse events (TEAE) were secondary endpoints. RESULTS: After 2-week EBR/GZR treatment, the virologic response rate was 85.1% (80/94) and reached 100% (94/94) after 8 and 12 weeks of therapy. Sustained virologic response (SVR) rates were 100% at the 12, 24 and 48-week follow-ups. Multivariate analysis revealed that the baseline viral load of HCV RNA may affect the rapid 2-week virologic response (OR: 0.36, 95% CI: 0.14-0.92, P=0.034), but did not influence efficacy during further treatment or follow-ups. Fifteen patients with ≥1 TEAE (16.0%) were observed and 7 (7.4%) and 8 (8.5%) patients had mild ALT or AST elevations (1.1-2.5× BL), but no serious drug-related AEs occurred. Liver stiffness measurement (LSM), the AST to platelet ratio index (APRI) and the fibrosis index based on 4 factor (FIB4) scores were consistently reduced, especially in patients with high baseline assessments after 12 weeks' treatment and during follow-ups. CONCLUSIONS: A 12-week EBR/GZR regimen shows high efficacy and safety in Chinese patients with GT1b HCV infections.

Cost-Effectiveness of Elbasvir/Grazoprevir for the Treatment of Chronic Hepatitis C: A Systematic Review.

Objective: This study aims to systematically review recent economic evaluations of elbasvir/grazoprevir (EBR/GZR) for chronic hepatitis C (CHC), to critically appraise the reporting quality and to summarize the results. Methods: A literature search was undertaken using Medline, Embase, the Cochrane Library, EconLit, China National Knowledge Infrastructure, Wanfang Data, and Chongqing VIP to identify original articles containing economic evaluations of EBR/GZR for CHC published between 1 January 2000 and 31 December 2020. The Consolidated Health Economic Evaluation Reporting Standards statement was used to assess the quality of reporting of the articles. Results: Of 93 articles identified, 13 studies fulfilled the inclusion criteria. These studies were conducted in 4 countries, and 8 active interventions were assessed. The target population was patients infected with CHC genotype 1 infection in all studies. Eight out of 13 studies that compared EBR/GZR vs. other direct antiviral agents suggested that EBR/GZR was generally more cost-effective or dominant than daclatasvir/asunaprevir (DCV/ASV), sofosbuvir/velpatasvir (SOF/VEL), ledipasvir/sofosbuvir (LDV/SOF), ombitasvir/paritaprevir/ritonavir + dasabuvir (3D) but not more cost-effective than glecaprevir/pibrentasvir (GLE/PIB). Two studies from China and one study from the USA that compared EBR/GZR vs. pegylated interferon and ribavirin (PegIFN/RBV) consistently indicated that EBR/GZR was generally more cost-effective than PegIFN/RBV. One study from Italy compared EBR/GZR with SOF + PegIFN/RBV and suggested that EBR/GZR had a lower cost and higher effectiveness. One study from France and one study from the USA confirmed that compared with non-therapy for patients with chronic kidney disease, EBR/GZR was cost-effective at commonly accepted current standards. All included studies were of good quality of reporting, with an average score of 21.9 (range 19-23). Conclusion: EBR/GZR for CHC genotype 1 might be cost-effective or dominant compared with PegIFN/RBV and other direct antiviral agents (SOF/VEL, 3D, DCV/ASV, LDF/SOF) or non-therapy. However, under certain assumptions, EBR/GZR was not a cost-effective alternative for CHC patients vs. GLE/PIB.

Transient flare of psoriasis under direct-acting antiviral therapy of chronic hepatitis C: A case report.

Extrahepatic manifestations of chronic hepatitis C virus (HCV) infection frequently involve the skin. Here, we report the case of a woman, who experienced a psoriasis exacerbation on DAA treatment, which lead to psoriasis resolution upon HCV clearance under continued treatment with elbasvir/grazoprevir.

The efficacy of Elbasvir/Grazoprevir fixed-dose combination for 8 weeks in HCV treatment and health-related quality of life (HRQoL) in treatment-naïve, non-cirrhotic, genotype 4-infected patients (ELEGANT-4): A single-center, single-arm, open-label, phase 3 trial.

Background: Cost, adverse events, and long treatment duration can be significant obstacles in treating hepatitis C virus (HCV)-infected individuals. Shortening the treatment regimen can minimize these barriers, thereby enhancing adherence and increasing medication availability to more patients. Methods: This is a single-centre, single-arm, open-label, phase 3 clinical trial on treatment naïve, non-cirrhotic, HCV genotype 4 patients. The study aimed to evaluate an 8-week course of Elbasvir (ELB)/Grazoprevir (GZR) in this population. The primary endpoint was sustained virologic response at 12 weeks after the end of treatment (SVR-12). The secondary endpoints were SVR-4, adverse events, and changes in health- and hepatitis-related quality of life (HRQoL). Results: Of the 30 patients who were enrolled, 29 (97%) achieved SVR-12 and SVR-4 (95% CI: 90-100%). No patients experienced serious or life-threatening adverse events (AEs), but mild/moderate AEs were reported by 16 (53%). The most commonly reported AEs were itching/skin rash (20%), headache (16.7%), abdominal/epigastric pain and decreased appetite (13.3% each), and nausea/vomiting (10%). Marked improvements in HRQoL were reported between the first (baseline) and third (SVR-12) timepoints. HRQoL score improvements involved the physical, mental, and hepatitis-specific indices, and ranged between 6 and 42 points (out of 100, P ≤0.003). Conclusion: The trial provides empirical evidence that HCV genotype 4-infected patients can achieve viral eradication with an 8-week-regimen of ELB/GZR. Further, this course of treatment is associated with a minimal adverse event profile and potentially significant improvements in quality of life. (ClinicalTrials.gov number, NCT03578640).

Targeting allosteric pockets of SARS-CoV-2 main protease Mpro.

Repurposing of antivirals is an attractive therapeutic option for the treatment of COVID-19. Main protease (Mpro), also called 3 C-like protease (3CLpro) is a key protease of SARS-CoV-2 involved in viral replication, and is a promising drug target for antivirals. A major challenge to test the efficacy of antivirals is the conformational plasticity of Mpro and its future mutation prone flexibility. Suitable choice of drugs in catalytic and allosteric pockets appear to be essential for combination therapy. Current study, based on docking and extensive set of MD simulations, finds the combination of Elbasvir, Glecaprevir and Ritonavir to be a viable candidate for further experimental drug testing/pharmacophore design for Mpro.Communicated by Ramaswamy H. Sarma.

Safety and efficacy of grazoprevir/elbasvir in the treatment of acute hepatitis C in hemodialysis patients.

Treatment of hepatitis C virus (HCV) infection with direct-acting antiviral agents (DAAs) in hemodialysis patients requires extensive consideration. At present, studies regarding DAAs for acute HCV infection in such patients are limited. The present study aims to evaluate the efficacy and safety of grazoprevir (GZR) plus elbasvir (EBR) treatment in acute hepatitis C (AHC) patients undergoing hemodialysis. Patients undergoing hemodialysis who had a nosocomial acute HCV infection were enrolled. All patients received GZR 100 mg/EBR 50 mg once daily for 12 weeks and were followed up for 12 weeks. Serum alanine transaminase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), and HCV RNA levels were monitored during treatment and follow-up periods. Sustained virologic response at 12 weeks after treatment cessation and treatment-emergent adverse events (AEs) were assessed. A total of 68 AHC patients were enrolled. All patients were infected with HCV genotype 1b and achieved SVR12. Decreasing ALT, AST, and TBIL were observed over time in the first 4 weeks and became steady thereafter. Forty-eight (70.59%) patients reported at least one AEs. The most common AEs were fatigue, headache, and nausea. Two AHC patients discontinued treatment due to serious but drug-unrelated AEs. In conclusion, GZR/EBR has a high efficacy and safety profile in hemodialysis-dependent patients with genotype 1b AHC.

Cost-Effectiveness of Testing for NS5A Resistance to Optimize Treatment of Elbasvir/Grazoprevir for Chronic Hepatitis C in China.

Objectives: Baseline presence of nonstructural protein 5A (NS5A) resistance-associated variants can attenuate the efficacy of new direct-acting antivirals. A potential method to attain the higher efficacy would be to screen for NS5A polymorphisms prior to the initiation of therapy and to adjust the treatment length based on the test results. However, baseline testing adds additional costs and it is unclear whether this would represent a high value strategy for chronic hepatitis C in China. Methods: A hybrid model compared 1) standard 12-weeks treatment (no testing), 2) shortened 8-weeks treatment (no testing), and 3) baseline testing with 12-/8-weeks treatment for those with/without NS5A polymorphisms from a lifetime Chinese health care payer perspective. All model inputs were retrieved from clinical trials and publically available literature. And sensitivity analyses were also conducted to assess the impact of uncertainty. Results: Baseline testing was associated with overall increase in total health care cost of USD 13.50 and in QALYs of 0.002 compared with standard 12-weeks treatment (no testing), yielded in an ICER of USD 6750/QALY gained. Scenario analyses suggested that shortened 8-weeks treatment (no testing) was found to be lower costs and great QALYs compared with other two strategies when the sustained virologic response (SVR) rate increased to 95%. Sensitivity analyses indicated that the results were robust. Conclusions: Our results suggest prior assessment of NS5A sensitivity followed by optimizing treatment duration was an economic strategy. In addition, shortened 8-weeks treatment (no testing) was shown to be dominant with the SVR rate increased to 95%.

Elbasvir/grazoprevir administered for 12 weeks via percutaneous endoscopic gastrostomy tube achieves sustained virologic response: A case report and a review of the literature.

Enteral tubes are necessary for certain patients; however, medication absorption can be affected by this route of administration potentially resulting in decreased efficacy. All first-line treatments for Hepatitis C Virus (HCV) infection are only available as tablets and may have decreased absorption if administered via an enteral tube. This report describes the first case of a pegylated interferon and ribavirin treatment-experienced patient who successfully achieved HCV cure after 12 weeks of elbasvir/grazoprevir administered via percutaneous gastrostomy tube. We further review the available pharmacokinetic and clinical literature regarding administration via enteral feeding tubes for all first-line direct-acting antivirals (DAAs). The literature suggests that crushed administration can be considered for DAAs in patients with gastric access. However, caution should be exercised in patients with extragastric enteral tubes and in those with altered gastrointestinal tract anatomy.

Impact of recent drug use on the efficacy of elbasvir/grazoprevir for HCV-infected people on opioid agonist therapy.

Elbasvir/grazoprevir (EBR/GZR) use in drug users on opiate agonist therapy (OAT) is supported by the C-EDGE Co-STAR trial. SVR rates in this study were within those found in the rest of patients included by the EBR/GZR development programme. In clinical practice, however, efficacy could theoretically be lower. Thus, we aimed at evaluating the SVR rates of EBR/GZR among people who injected drugs (PWID) with and without OAT in clinical practice. Patients starting EBR/GZR included in the HEPAVIR-DAA (NCT02057003), recruiting HIV/HCV-coinfected patients or the GEHEP-MONO (NCT02333292), including HCV-monoinfected individuals, prospective cohorts were analysed. Overall SVR12 (ITT), discontinuations due to adverse effects and drop-outs were evaluated. The same analysis was carried out for PWID with and without OAT. 336 patients had started EBR/GZR and reached the SVR12 evaluation date. 318 [95%, 95% confidence interval (95% CI): 92%-98%] patients achieved SVR12. SVR12 was 97% (95% CI: 93%-99%, n/N = 141/145) among people who never used injecting drugs, 94% (95% CI: 88%-97%, n/N = 117/125) among PWIDs without OAT and 91% (95% CI: 81%-97%, n/N = 60/66) among PWIDs with OAT (p = 0.134). Five (1.5%) patients showed relapses, and two (0.6%) individuals showed viral breakthrough. The SVR12 rate for recent drug users was 69% (n/N = 18/26) compared with 97% (n/N = 276/284) for individuals without recent drug use (in the prior year) (p < 0.001). Among recent drug users, three (12%) showed relapses, and five (19%) were lost-to-follow-up. The SVR rates achieved with EBR/GZR were high in real-world conditions of use. However, PWID with recent drug use reach suboptimal response rates with EBR/GZR.

Drug repositioning to target NSP15 protein on SARS-CoV-2 as possible COVID-19 treatment.

SARS-CoV and SARS-CoV-2 belong to the subfamily Coronaviridae and infect humans, they are constituted by four structural proteins: Spike glycoprotein (S), membrane (M), envelope (E) and nucleocapsid (N), and nonstructural proteins, such as Nsp15 protein which is exclusively present on nidoviruses and is absent in other RNA viruses, making it an ideal target in the field of drug design. A virtual screening strategy to search for potential drugs was proposed, using molecular docking to explore a library of approved drugs available in the DrugBank database in order to identify possible NSP15 inhibitors to treat Covid19 disease. We found from the docking analysis that the antiviral drugs: Paritaprevir and Elbasvir, currently both approved for hepatitis C treatment which showed some of the lowest free binding energy values were considered as repositioning drugs to combat SARS-CoV-2. Furthermore, molecular dynamics simulations of the Apo and Holo-Nsp15 systems were performed in order to get insights about the stability of these protein-ligand complexes.

Simultaneous spectrophotometric quantitative analysis of elbasvir and grazoprevir using assisted chemometric models.

Artificial neural networks and genetic algorithm artificial neural networks, chemometric assisted spectrophotometric models, were developed for the quantitative analysis of elbasvir and grazoprevir in their newly FDA approved pharmaceutical dosage form. The UV absorption spectra of elbasvir and grazoprevir show severe degree of overlap which caused difficulty for selecting certain spectrophotometric method with advantage of simultaneous quantitative analysis of the cited drugs. After extensive study and many experimental trials, artificial neural networks and genetic algorithm artificial neural networks were the suitable models for the quantitative analysis of studied drugs in their binary mixture. Experimental design and constructing the calibration and validation sets of the binary mixture were achieved to implement the proposed models. The models were optimized with the aid of five-levels, two factors experimental design. The designed models were successfully applied to the quantitative analysis of Zepatier® tablets. The results were statistically compared with another reported HPLC quantitative analytical method with no significant difference by applying Student t-test and variance ratio F-test.

Elbasvir and grazoprevir for the treatment of hepatitis C.

Introduction: Hepatitis C is one of the leading causes of chronic liver disease. The direct-acting-antivirals has revolutionized the chronic hepatitis C treatment. DAAs can achieve a sustained virological response rate >95% in different populations.Area covered: This review summarizes the pharmacokinetics, pharmacodynamics, efficacy, and safety of Elbasvir/Grazoprevir (EBR/GZR).Expert opinion: EBR/GZR is a combination of NS5A and NS3/4A inhibitors. The performance in the EBR/GZR combination's safety and tolerability is appreciated in clinical treatment. EBR/GZR also has a higher barrier to resistance-associated substitutions. Based on clinical trials and real-world experience, elbasvir/grazoprevir is effective in the HCV GT1, 4 infections.

Effectiveness and safety of elbasvir/grazoprevir in Korean patients with hepatitis C virus infection: a nationwide real-world study.

BACKGROUND/AIM: This study aimed to establish the real-world effectiveness and safety of grazoprevir/elbasvir (EBR/GZR) therapy in South Korea. METHODS: A total of 242 patients with chronic hepatitis C virus (HCV) genotype 1 or 4 infection who started EBR/GZR were consecutively enrolled from seven tertiary hospitals. Retrospective analysis of the fractions of patients that achieved sustained virological response (SVR) was performed, and the incidence of adverse events was noted. RESULTS: The mean age of enrolled patients was 59.0 ± 12.6 years and 47.5% were males. Patients with HCV genotype 1b accounted for 93.8% (n = 227), and patients with HCV of unspecified genotype 1 accounted for 5.8% (n = 14). Hypertension was the most common comorbid disease (29.8%) followed by diabetes (22.7%) and chronic kidney disease (CKD, 12.4%). SVR rates of treatment-naïve and treatment-experienced patients were 85.5% (182/213) and 93.1% (27/29), respectively, in the intention-to-treat analyses, whereas in the per-protocol analyses, those were 97.8% (179/183) and 100% (28/28), respectively. Fewer patients with HCV genotype 1 of unspecified subtype achieved SVR (81.8%, n = 11) compared to the patients with SVR infected with genotype 1b (99%, n = 198, p < 0.001). All patients with CKD showed SVR. Itching (12%) and dyspepsia (4.1%) were common adverse events. Of the four patients who discontinued the antiviral therapy, one experienced mild fatigue but neither treatment withdrawal was because of an adverse event. CONCLUSION: EBR/GZR showed high real-world effectiveness and safety in Korean patients with chronic HCV infection regardless of the previous antiviral treatment, liver cirrhosis, or CKD status.

Simultaneous determination of elbasvir and grazoprevir in their pharmaceutical formulation by synchronous fluorescence spectroscopy coupled to dual wavelength method.

In the present study, a sensitive, selective and accurate synchronous fluorescence spectroscopic method was utilized for simultaneous estimation of elbasvir and grazoprevir in their pharmaceutical formulation. The developed method based on measurement of the synchronous fluorescence intensity of the studied drugs at constant wavelength difference (Δλ) = 50 nm. Elbasvir can be determined directly at 312 nm without interference from grazoprevir. Grazoprevir can be determined by application of dual wavelength method by taking the difference in synchronous fluorescence intensity at 390 & 372 nm to remove interference from elbasvir. Calibration graphs were found to be linear over the concentration range of 50-700 ng/mL for elbasvir and 100-900 ng/mL for grazoprevir. The developed method was successfully applied to the quantitative analysis of the two drugs in Zepatier® tablets.

Cost-Utility of All-Oral Direct-Acting Antiviral Regimens for the Treatment of Genotype 1 Chronic Hepatitis C Virus-Infected Patients in Hong Kong.

BACKGROUND: Direct-acting antivirals (DAAs) are entering the hepatitis C virus (HCV) treatment landscape in Hong Kong, prompting the need for cost-effectiveness evaluations of these interventions to enable optimal use of healthcare resources. AIMS: This study aimed to compare the cost-effectiveness of DAAs to standard-of-care pegylated interferon plus ribavirin (RBV) in treatment-naïve patients without significant liver fibrosis and to compare different DAAs in patients who are treatment-experienced and/or have advanced liver disease. METHODS: A Markov model was constructed to evaluate cost-effectiveness over a lifetime time horizon from the payer perspective. The target population was treatment-naïve and treatment-experienced HCV genotype 1 patients, stratified by degree of liver fibrosis. The model consists of 16 health states encompassing METAVIR fibrosis score (F0-F4), treatment success or failure, decompensated cirrhosis, hepatocellular carcinoma, liver transplant, and liver-related death. The proportions of patients achieving sustained virologic response were obtained from clinical trials. Other inputs were obtained from published and local data. The primary outcome was incremental cost-utility ratio for each DAA versus pegylated interferon + ribavirin and among different DAAs. RESULTS: In treatment-naïve F0-2 HCV patients, all DAAs were cost-effective in genotype 1a and daclatasvir + asunaprevir, elbasvir/grazoprevir, ledipasvir/sofosbuvir, and glecaprevir/pibrentasvir were cost-effective compared to pegylated interferon + ribavirin in genotype 1b. In genotypes 1a and 1b, treatment-experienced patients, and F3-4 patients, elbasvir/grazoprevir was the least costly DAA and economically dominant over most other DAAs. CONCLUSIONS: DAAs can be a cost-effective option for the treatment of genotype 1 HCV patients in Hong Kong, and elbasvir/grazoprevir is cost-effective.