A therapeutic dose and its pharmacokinetics of ropeginterferon Alfa-2b for hepatitis C treatment.

AIM: Ropeginterferon alfa-2b is a novel mono-pegylated proline-interferon. Its biweekly dosing schema has demonstrated tolerability and clinical efficacy for treating chronic hepatitis in previous clinical studies. This trial evaluates the pharmacokinetics of 400 µg ropeginterferon alfa-2b in patients with chronic hepatitis C virus (HCV) and provides the data to support the clinical utility of ropeginterferon alfa-2b at 400 µg. METHODS: Seventeen patients with chronic HCV genotype 2 were enrolled to receive a single injection of 400 µg ropeginterferon alfa-2b plus 14-day treatment of ribavirin. Pharmacokinetics, safety, and HCV RNA reduction/clearance were assessed. RESULTS: Tmax was 154.003 h and T1/2 was 114.273 h. The Cmax was 29.823 ng mL-1. AUClast was 9364.292 h∗ng mL-1 and AUCinf was 11084.317 h∗ng mL-1. All adverse events were mild or moderate, and there were no serious adverse events. A 1000-fold reduction in the geometric mean of HCV RNA was observed 14 d after the single injection of ropeginterferon alfa-2b. Two patients achieved clearance of HCV RNA, and the other five patients had HCV RNA levels lower than 200 IU mL-1. CONCLUSION: Ropeginterferon alfa-2b at 400 µg led to PK exposures associated with safety and notable clinical activity in patients with chronic HCV. This study suggests that ropeginterferon alfa-2b at 400 µg is an acceptable dosing regimen for treating chronic HCV and also provides supporting data for the clinical use of ropeginterferon alfa-2b at a higher starting dose for other indications.

Development of a Nanobody-Based Competitive Enzyme-Linked Immunosorbent Assay for Efficiently and Specifically Detecting Antibodies against Genotype 2 Porcine Reproductive and Respiratory Syndrome Viruses.

Porcine reproductive and respiratory syndrome virus (PRRSV) infection causes considerable economic loss to the global pig industry. Efficient detection assay is very important for the prevention of the virus infection. Nanobodies are the advantages of small molecular weight, simple genetic engineering, and low production cost for promising diagnostic application. In this study, to develop a nanobody-based competitive ELISA (cELISA) for specifically detecting antibodies against PRRSV, three nanobodies against PRRSV-N protein were screened by camel immunization, library construction, and phage display. Subsequently, a recombinant HEK293S cell line stably secreting nanobody-horseradish peroxidase (HRP) fusion protein against PRRSV-N protein was successfully constructed using the lentivirus transduction assay. Using the cell lines, the fusion protein was easily produced. Then, a novel cELISA was developed using the nanobody-HRP fusion protein for detecting antibodies against PRRSV in pig sera, exhibiting a cut-off value of 23.19% and good sensitivity, specificity, and reproducibility. Importantly, the cELISA specifically detect anti-genotype 2 PRRSV antibodies. The cELISA showed more sensitive than the commercial IDEXX ELISA kit by detecting the sequential sera from the challenged pigs. The compliance rate of cELISA with the commercial IDEXX ELISA kit was 96.4%. In addition, the commercial IDEXX ELISA kit can be combined with the developed cELISA for the differential detection of antibodies against genotype 1 and 2 PRRSV in pig sera. Collectively, the developed nanobody-based cELISA showed advantages of simple operation and low production cost and can be as an assay for epidemiological investigation of genotype 2 PRRSV infection in pigs and evaluation after vaccination.

Prevalence, characteristics, and distribution of HPV genotypes in women from Zhejiang Province, 2016-2020.

OBJECTIVE: To evaluate and understand the prevalence of HPV genotypes and characteristics of female populations in specific areas and the relationship with cervical lesions, which can effectively guide cervical cancer screening and formulate HPV vaccine prevention strategies. METHODS: A total of 77,443 women who visited gynecological clinics and underwent health examinations in the Second Affiliated Hospital of Zhejiang University School of Medicine during 2016-2020 were enrolled in this survey. Cervical samples were collected for HPV DNA genotyping and cervical cytology testing. Cervical biopsies were performed for patients with visible cervical abnormality or abnormal cytological results. RESULTS: The results showed the 5-year overall positive rate was 22.3%, of which the gynecology clinic group had significantly more positive results compared with the health examination group (P < 0.001). The five most common genotypes in Zhejiang Province were HPV 52, 58, CP8304, 16, and 51 (23.9%, 12.7%, 11.7%, 11.7% and 9.3%). HPV infection was age-specific, with the highest infection rate in the age group ≤ 20 compared to other age groups (P < 0.001). HPV infection was also season-specific, with the highest infection rate in spring or winter. The main HPV infection mode was single infection (P = 0.004), but patients ≤ 20 years old were more likely to develop multiple infections (51.0%). HPV 16, 52 and 58 were the main genotypes that caused cytological abnormalities and HPV16, 18, 56, 58 and 66 were independent risk factors for cervical lesions (OR = 2.352, 1.567, 2.000, 1.694, 1.889; all P < 0.05). Further analysis found HPV 16 and 18 were the main genotypes that cause cervical cancer histological abnormalities and were independent risk factors for cervical cancer (OR = 5.647, P < 0.001; OR = 3.495, P = 0.036). CONCLUSION: This article analyzed the prevalence of distribution characteristics of HPV infection and revealed the corelation between HPV infection and cytological and histological abnormalities. Comprehensive results of this survey will help Zhejiang Province to formulate public health policies and provide evidence for future selection of specific HPV vaccines.

A new Hendra virus genotype found in Australian flying foxes.

BACKGROUND: Hendra virus (HeV) has caused lethal disease outbreaks in humans and horses in Australia. Flying foxes are the wildlife reservoir from which the virus was first isolated in 1996. Following a heat stress mortality event in Australian flying foxes in 2013, a novel HeV variant was discovered. This study describes the subsequent surveillance of Australian flying foxes for this novel virus over a nine year period using qRT-PCR testing of tissues from flying foxes submitted primarily for Australian bat lyssavirus diagnosis. Genome sequencing and characterisation of the novel HeV variant was also undertaken. METHODS: Spleen and kidney samples harvested from flying fox carcasses were initially screened with two real-time qRT-PCR assays specific for the prototype HeV. Two additional qRT-PCR assays were developed specific for the HeV variant first detected in samples from a flying fox in 2013. Next-generation sequencing and virus isolation was attempted from selected samples to further characterise the new virus. RESULTS: Since 2013, 98 flying foxes were tested and 11 were positive for the new HeV variant. No samples were positive for the original HeV. Ten of the positive samples were from grey-headed flying foxes (GHFF, Pteropus poliocephalus), however this species was over-represented in the opportunistic sampling (83% of bats tested were GHFF). The positive GHFF samples were collected from Victoria and South Australia and one positive Little red flying fox (LRFF, Pteropus scapulatus) was collected from Western Australia. Immunohistochemistry confirmed the presence of henipavirus antigen, associated with an inflammatory lesion in cardiac blood vessels of one GHFF. Positive samples were sequenced and the complete genome was obtained from three samples. When compared to published HeV genomes, there was 84% sequence identity at the nucleotide level. Based on phylogenetic analyses, the newly detected HeV belongs to the HeV species but occupies a distinct lineage. We have therefore designated this virus HeV genotype 2 (HeV-g2). Attempts to isolate virus from PCR positive samples have not been successful. CONCLUSIONS: A novel HeV genotype (HeV-g2) has been identified in two flying fox species submitted from three states in Australia, indicating that the level of genetic diversity for HeV is broader than first recognised. Given its high genetic relatedness to HeV, HeV-g2 is a zoonotic pathogen.

Monoclonal antibodies specific for the hemagglutinin-neuraminidase protein define neutralizing epitopes specific for Newcastle disease virus genotype 2.VII from Egypt.

BACKGROUND: Newcastle disease is a devastating disease in poultry caused by virulent Newcastle disease virus (NDV), a paramyxovirus endemic in many regions of the world despite intensive vaccination. Phylogenetic analyses reveal ongoing evolution of the predominant circulating genotype 2.VII, and the relevance of potential antigenic drift is under discussion. To investigate variation within neutralization-sensitive epitopes within the protein responsible for receptor binding, i.e. the Hemagglutinin-Neuraminidase (HN) spike protein, we were interested in establishing genotype-specific monoclonal antibodies (MAbs). METHODS: An HN-enriched fraction of a gradient-purified NDV genotype 2.VII was prepared and successfully employed to induce antibodies in BalbC mice that recognize conformationally intact sites reactive by haemagglutination inhibition (HI). For subsequent screening of mouse hybridoma cultures, an NDV-ELISA was established that utilizes Concanavalin A (ConA-ELISA) coupled glycoproteins proven to present conformation-dependent epitopes. RESULTS: Six out of nine selected MAbs were able to block receptor binding as demonstrated by HI activity. One MAb recognized an epitope only present in the homologue virus, while four other MAbs showed weak reactivity to selected other genotypes. On the other hand, one broadly cross-reacting MAb reacted with all genotypes tested and resembled the reactivity profile of genotype-specific polyclonal antibody preparations that point to minor antigenic differences between tested NDV genotpyes. CONCLUSIONS: These results point to the concurrent presence of variable and conserved epitopes within the HN molecule of NDV. The described protocol should help to generate MAbs against a variety of NDV strains and to enable in depth analysis of the antigenic profiles of different genotypes.

Effectiveness and safety of ledipasvir/sofosbuvir for genotype 2 chronic hepatitis C infection: Real-world experience from Taiwan.

BACKGROUND/PURPOSE: Genotype 2 (GT2) hepatitis C virus infection is the second common genotype in Taiwan. Real-world experience of ledipasvir/sofosbuvir (LDV/SOF) for GT2 infection is limited. The aim of this study is to evaluate the effectiveness and safety of LDV/SOF in patients with GT2 chronic hepatitis C (CHC) infection. METHODS: CHC patients with GT2 infection receiving 12 weeks LDV/SOF from three hospitals were enrolled. HCV RNA was checked at baseline, end-of-treatment and 12 weeks after completing treatment. Demographic data, adverse events, renal function and metabolic profiles were recorded. RESULTS: Among 392 enrolled patients, 33 patients (8.4%) were cirrhotic. Sustained virological response (SVR) rate was 96.7% (379/392) by intention-to-treat analysis and 97.2% (379/390) by per-protocol analysis. The SVR rate was lower in cirrhotic patients than in non-cirrhotic patients (90.6% vs 97.8%, p = 0.053). Two cirrhotic patients who took LDV/SOF plus ribavirin both achieved SVR. Neither drug-related severe adverse events nor discontinuation due to drug-related adverse event were reported. The estimated glomerular filtration rate (eGFR) remained stable in patients with chronic kidney disease 3a/3b. CONCLUSION: Twelve weeks of LDV/SOF treatment provided an excellent and safe regimen for GT2 CHC infection, particularly in non-cirrhotic patients.

Ropeginterferon Alfa-2b administered every two weeks for patients with genotype 2 chronic hepatitis C.

BACKGROUND: Ropeginterferon alfa-2b is a novel mono-pegylated interferon that has only one major form as opposed to the 8 to 14 isomers of other on-market pegylated interferon products, allowing every-two-week injection with high tolerability. It received European Medicines Agency marketing authorization in 2019 and Taiwan Biologics License Applications Approval in 2020 for the treatment of polycythemia vera. This study aimed to evaluate the safety and efficacy of Ropeginterferon alfa-2b plus ribavirin in genotype 2 chronic hepatitis C (CHC) patients. METHODS: Eighty-six treatment naive patients with genotype 2 CHC were randomized to weekly peginterferon alfa-2a (Peg-IFN-α2a) at 180 µg (n = 22), or every-two-week Ropeginterferon alfa-2b at 270 µg (n = 23), 360 µg (n = 21), 450 µg (n = 20), plus daily oral ribavirin 1000 mg (≤75 kg) or 1200 mg (>75 kg). Patients with rapid virologic response received 16-week regimen while those without RVR received 24-week regimen. The primary endpoint was sustained virologic response at 24 weeks post-treatment (SVR24). RESULTS: SVR24 was achieved by 95.5%, 78.3%, 85.7%, and 60% of subjects in Peg-IFN-α2a 180 µg, Ropeginterferon alfa-2b 270 µg, 360 µg, and 450 µg groups, respectively. The safety profile was similar across 4 groups. The incidence rate of adverse event during the treatment period was 0.407, 0.252, 0.395, and 0.347 per patient-week, respectively. CONCLUSION: Ropeginterferon alfa-2b, although at only half the number of injections, is as safe and effective as Peg-IFN-α2a for genotype 2 CHC. A phase 3 study to confirm safety and efficacy of Ropeginterferon alfa-2b in genotype 2 CHC is ongoing.

Cell Culture Studies of the Efficacy and Barrier to Resistance of Sofosbuvir-Velpatasvir and Glecaprevir-Pibrentasvir against Hepatitis C Virus Genotypes 2a, 2b, and 2c.

The introduction of highly efficient therapies with direct-acting antivirals (DAA) for patients with chronic hepatitis C virus (HCV) infection offers exceptional opportunities to globally control this deadly disease. For achieving this ambitious goal, it is essential to prevent antiviral resistance against the most optimal first-line and retreatment DAA choices. We performed independent comparisons of the efficacy and barrier to resistance of pangenotypic DAA regimens for HCV genotype 2 infections, using previously and newly developed efficient cell culture-adapted strains of subtypes 2a, 2b, and 2c. With the applied experimental cell culture conditions, combination treatment with the sofosbuvir-velpatasvir or glecaprevir-pibrentasvir DAA regimen was efficient in eradicating HCV infections; in contrast, single-drug treatments frequently led to viral escape. Sequence analysis of drug targets from recovered viruses revealed known resistance-associated substitutions (RAS) emerging in the NS3 protease or NS5A after treatment failure. These RAS were genetically stable after viral passage, and viruses with these RAS exhibited significant phenotypic resistance. After sofosbuvir treatment failure, only a genotype 2a virus harbored NS5B RAS S282T and thus had decreased susceptibility to nucleotide analogs (nucs). However, in most cases, viral escape from sofosbuvir led to other NS5B substitutions but drug susceptibility was maintained, and in one case, no changes in NS5B were detected. For a genotype 2b virus, after treatment failure with sofosbuvir-velpatasvir, the efficacy of retreatment with glecaprevir-pibrentasvir was maintained due to the high barrier to resistance and low cross-resistance of pibrentasvir. Our findings suggest the slight superiority of glecaprevir-pibrentasvir against genotype 2b in culture, which could have potential therapeutic interest meriting more definitive investigations in the clinic.

A Recombinant Hepatitis C Virus Genotype 1a E1/E2 Envelope Glycoprotein Vaccine Elicits Antibodies That Differentially Neutralize Closely Related 2a Strains through Interactions of the N-Terminal Hypervariable Region 1 of E2 with Scavenger Receptor B1.

The global health burden for hepatitis C virus (HCV) remains high, despite available effective treatments. To eliminate HCV, a prophylactic vaccine is needed. One major challenge in the development of a vaccine is the genetic diversity of the virus, with 7 major genotypes and many subtypes. A global vaccine must be effective against all HCV genotypes. Our previous data showed that the 1a E1/E2 glycoprotein vaccine component elicits broad cross-neutralizing antibodies in humans and animals. However, some variation is seen in the effectiveness of these antibodies to neutralize different HCV genotypes and isolates. Of interest was the differences in neutralizing activity against two closely related isolates of HCV genotype 2a, the J6 and JFH-1 strains. Using site-directed mutagenesis to generate chimeric viruses between the J6 and JFH-1 strains, we found that variant amino acids within the core E2 glycoprotein domain of these two HCV genotype 2a viruses do not influence isolate-specific neutralization. Further analysis revealed that the N-terminal hypervariable region 1 (HVR1) of the E2 protein determines the sensitivity of isolate-specific neutralization, and the HVR1 of the resistant J6 strain binds scavenger receptor class-B type-1 (SR-B1), while the sensitive JFH-1 strain does not. Our data provide new information on mechanisms of isolate-specific neutralization to facilitate the optimization of a much-needed HCV vaccine.IMPORTANCE A vaccine is still urgently needed to overcome the hepatitis C virus (HCV) epidemic. It is estimated that 1.75 million new HCV infections occur each year, many of which will go undiagnosed and untreated. Untreated HCV can lead to continued spread of the disease, progressive liver fibrosis, cirrhosis, and eventually, end-stage liver disease and/or hepatocellular carcinoma (HCC). Previously, our 1a E1/E2 glycoprotein vaccine was shown to elicit broadly cross-neutralizing antibodies; however, there remains variation in the effectiveness of these antibodies against different HCV genotypes. In this study, we investigated determinants of differential neutralization sensitivity between two highly related genotype 2a isolates, J6 and JFH-1. Our data indicate that the HVR1 region determines neutralization sensitivity to vaccine antisera through modulation of sensitivity to antibodies and interactions with SR-B1. Our results provide additional insight into optimizing a broadly neutralizing HCV vaccine.

Sofosbuvir-Daclatasvir is suboptimal in patients with genotype 2 chronic hepatitis C infection: real-life experience from the HEPATHER ANRS CO22 cohort.

Sofosbuvir plus daclatasvir with or without ribavirin has demonstrated a high efficacy and an acceptable safety profile in clinical trials of patients infected with genotype 2 hepatitis Cvirus (HCV); however, there are currently no real-world data available for this regimen. To evaluate the real-life safety and efficacy of sofosbuvir/daclatasvir with or without ribavirin in genotype 2 HCV patients in the French cohort ANRS CO22 HEPATHER(NCT01953458). In this ongoing, national, multicentre, prospective, observational study, we observed patients with HCV genotype 2 infection who initiated treatment with sofosbuvir (400 mg/d) plus daclatasvir with or without ribavirin (1-1.2 g/d). Patients were divided into two treatment groups: sofosbuvir/daclatasvir with or without ribavirin (12 weeks/24 weeks). The primary end point was a sustained virological response at week 12 following the end of therapy. Overall, 88% and 91% of patients achieved a sustained virological response following 12 and 24 weeks of treatment with sofosbuvir/daclatasvir with or without ribavirin, respectively. The most common adverse events were asthenia (29%), headache (15%) and fatigue (20%), and ribavirin addition was associated with a higher rate of adverse events and treatment discontinuation. Sofosbuvir/daclatasvir with or without ribavirin was associated with lower rates of sustained virological response in the real-life setting compared with the clinical setting and demonstrated suboptimal efficacy for the treatment of patients with genotype 2 chronic HCV.

Ledipasvir and sofosbuvir for 12 weeks for hepatitis C virus genotype 2 infection: A propensity score matched analysis.

AIM: Hepatitis C virus genotype 2 is common in East Asia, sub-Saharan Africa, and Latin America. However, many countries in these areas lag behind other areas of the world in government approval for new direct-acting antivirals. The aim of this study was to evaluate the treatment outcome of ledipasvir/sofosbuvir (LDV/SOF) for patients with chronic hepatitis C virus genotype 2 infection. METHODS: This is a two-part multicenter, real-world cohort study. Study 1 consisted of 58 consecutive patients who were treated with LDV/SOF for 12 weeks. Study 2 used propensity score matching for LDV/SOF (n = 58) and glecaprevir/pibrentasvir (n = 207) treatment groups (1:1) with a set of clinically important variables. Sustained viral response 12 weeks after the end of treatment (SVR12) and adverse events were evaluated in both studies. RESULTS: In study 1, the overall SVR12 rates of the intention-to-treat and modified intention-to-treat populations were 94.8% (55/58) and 96.5% (55/57), respectively. High SVR12 rates were observed in almost all subgroups, including older age, compensated cirrhosis, and treatment experience. In study 2, propensity score matching of the entire study population yielded 52 matched pairs with similar baseline characteristics. There were no statistically significant differences between the LDV/SOF (96.1%) and glecaprevir/pibrentasvir (98.0%) groups in the overall SVR12 rates of the modified intention-to-treat populations, and their rates of treatment discontinuation and adverse events were similar. CONCLUSIONS: Treatment with LDV/SOF for hepatitis C virus genotype 2 resulted in a high rate of SVR12 and excellent tolerability. The outcomes of LDV/SOF were very similar to those of glecaprevir/pibrentasvir.

Efficacy and safety of ombitasvir/paritaprevir/ritonavir and ribavirin for chronic hepatitis patients infected with genotype 2a in Japan.

AIM: The aim of this study was to evaluate the efficacy and safety of community-based ombitasvir/paritaprevir/ritonavir plus ribavirin therapy for non-cirrhotic patients with hepatitis C virus (HCV) genotype 2a infection in a real-world setting. METHODS: Patients with HCV genotype 2a infection were enrolled in this study and received the therapy for 16 weeks at 11 specialized centers in Japan between October 2016 and July 2017. Among the 98 patients participating in the study, four patients were excluded because of the presence of cirrhosis and/or genotype 2b infection. The remaining 94 patients were subjected to the analysis. RESULTS: The patients consisted of 38 women and 56 men, with a median age of 63 years. The rate of sustained virologic response (SVR) was 97.9%. The SVR rates were similar between patients with and without ribavirin dose reduction (96.0% vs. 98.6%, respectively). Of the two patients in whom treatment failed, one patient completed the treatment but relapsed at 4 weeks post-treatment, whereas the other did not show virologic response and therefore discontinued treatment at week 9. At baseline, both patients had non-structural protein (NS)5A resistance-associated substitution (RAS) L31M but no NS3 RAS. At the time of relapse, the patient had NS5A RAS F28S. At the premature treatment discontinuation, the non-responder had NS3 RAS D168V and NS5A RAS T24S. Ribavirin-induced anemia was the most frequent adverse event. CONCLUSION: Community-based, 16-week, ombitasvir/paritaprevir/ritonavir plus ribavirin therapy was highly efficacious and safe in non-cirrhotic patients with HCV genotype 2a infection in a real-world setting.

Effects of resistance-associated variants in genotype 2 hepatitis C virus on viral replication and susceptibility to antihepatitis C virus drugs.

AIMS: Development of direct-acting antivirals (DAAs) has made antihepatitis C virus (HCV) treatment highly safe and effective. However, the emergence of resistant-associated variants (RAVs) after failure of DAA therapy affects retreatment outcomes. In particular, genotype 1 HCV with P32 deletion has been reported to be highly resistant to all approved non-structural protein (NS)5A inhibitors. However, analysis of RAVs in genotype 2 HCV has been limited. Accordingly, in this study, we evaluated the roles of genotype 2 HCV variants in antiviral drug efficacy. METHODS: We utilized HCV-2b/2a (JFH-1) chimeric virus (genotype 2a), which replicates more robustly than JFH-1. We constructed various genotype 2a JFH-1-based HCV cell culture systems with NS3 (D168E), NS5A (F28S, F28S/M31I, P32 deletion, and Y93H), and NS5B (S282 T) RAVs and analyzed the replication ability and sensitivity to various anti-HCV reagents. RESULTS: Genotype 2a-based HCV with NS5A-P32 deletion could not replicate even in long-term cultures. Genotype 2a-based HCV with NS5A-F28S/M31I showed significantly higher replication ability than the wild-type strain, and replication could not be suppressed, even with high concentrations of NS5A inhibitors, including pibrentasvir and velpatasvir (<1000-10 000 fold-resistance compared with the wild-type strain). However, genotype 2a-based HCV with NA5A-F28S/M31I was sensitive to HCV protease inhibitor, NS5B inhibitor, interferon-α, and ribavirin. Genotype 2a-based HCV with NS5B-S282 T was resistant to sofosbuvir, but was highly sensitive to ribavirin compared with the control. CONCLUSIONS: When undertaking retreatment for genotype 2a HCV-infected patients who fail to respond to DAAs, the optimized retreatment should be chosen according to the sensitivity of the emerging RAVs to anti-HCV drugs.

Cost-effectiveness of sofosbuvir plus ribavirin therapy for hepatitis C virus genotype 2 infection in South Korea.

BACKGROUND AND AIM: For genotype 2 chronic hepatitis C (CHC), the efficacy and safety of sofosbuvir plus ribavirin therapy (SOF + RBV) was better than pegylated interferon plus ribavirin therapy (PR) at a greater drug cost. This study investigated the cost-effectiveness of SOF + RBV compared with PR for treatment-naïve genotype 2 CHC in South Korea. METHODS: Using a decision analytic Markov model, a cost-effectiveness analysis comparing SOF + RBV with PR or no treatment for treatment-naïve genotype 2 CHC was performed with probabilistic and deterministic sensitivity analyses from the payer's perspective in 2017. Three cohorts of patients aged 40-49, 50-59, and 60-69 years were simulated to progress through the fibrosis stages F0-F4 to end-stage liver disease, hepatocellular carcinoma, or death. Published and calculated data on the clinical efficacy of the regimen, health-related quality of life, costs, and transition probabilities were used. RESULTS: While the incremental cost-effectiveness ratio for PR was dominant over no treatment, the incremental cost-effectiveness ratios for SOF + RBV were $20 058 for the patients in their 40s, $19 662 for those in their 50s, and $22 278 for those in their 60s compared with PR. Probabilistic sensitivity analysis indicated an 89.0% probability for the SOF + RBV to be cost-effective at a willingness to pay of $29 754.4 (per-capita gross domestic product in 2017) for the patients in their 40s and 94.1% and 89.1% for the patients in their 50s and 60s, respectively. CONCLUSIONS: The SOF + RBV is a cost-effective option for genotype 2 treatment-naïve CHC patients, especially for the patients with liver cirrhosis in Korea.

Sofosbuvir-based direct acting antiviral therapies for patients with hepatitis C virus genotype 2 infection.

BACKGROUND AND AIM: Data regarding the comparative effectiveness and safety of sofosbuvir (SOF) in combination with ribavirin (RBV), daclatasvir (DCV), or ledipasvir (LDV) for hepatitis C virus genotype 2 (HCV-2) patients were limited. We aimed to evaluate the performance of these regimens in Taiwan. METHODS: One hundred eighty-seven HCV-2 patients with compensated liver diseases receiving SOF in combination with RBV (n = 82), DCV (n = 66), or LDV (n = 39) for 12 weeks were retrospectively enrolled. The effectiveness was determined by sustained virologic response 12 weeks off therapy (SVR12 ). The patient characteristics potentially related to SVR12 were compared. The safety profiles and laboratory abnormalities were assessed. RESULTS: The SVR12 rates were 93.9% (95% confidence interval [CI]: 86.5-97.4%), 98.5% (95% CI: 91.9-99.7%), and 100% (95% CI: 91.0-100%) in patients receiving SOF combined with RBV, DCV, and LDV, respectively. All patients tolerated treatment well. The stratified SVR12 rates were comparable regardless of baseline characteristics or week 4 viral decline among these regimens. Six (3.2%) patients had serious adverse events which were not related to treatment. The rates of fatigue, pruritus, and anemia tended to be higher in patients receiving RBV (22.0%, 19.5%, and 8.5%) combination than those receiving DCV (10.6%, 6.1%, and 1.5%) or LDV (10.3%, 5.1%, and 0%) combination. CONCLUSIONS: Sofosbuvir in combination with RBV, DCV, or LDV for 12 weeks is effective and well-tolerated for HCV-2 patients. Compared with DCV or LDV combination, the risks of fatigue, pruritus, and anemia are higher in patients receiving RBV combination.

Short communication: Occurrence and persistence of Prototheca zopfii in dairy herds of Korea.

Bovine mastitis caused by Prototheca has been reported globally, and its incidence is increasing in dairy herds. The present study aimed to investigate the occurrence of Prototheca and persistence of Prototheca zopfii strains in Korean dairy herds. A total of 187 (7.5%) P. zopfii strains were isolated from 2,508 quarter milk samples collected from 50 dairy farms throughout Korea from 2015 to 2017. Prototheca zopfii was isolated from one farm among the 50 farms over the 3-yr period. The P. zopfii isolates belonged to genotype 2. Overall, Prototheca-positive quarter milk samples showed high somatic cell counts with an average value of log 6.48 ± 6.54 cells/mL. Prototheca zopfii was found to be persistent in an infected farm over a 2-yr period. To the best of our knowledge, this is the first report on the presence and persistence of protothecal mastitis caused by P. zopfii genotype 2 in a Korean dairy herd. This disease leads to a significant increase in somatic cell counts in milk, which persists for more than 1 yr in the affected cow udder. These results suggest that P. zopfii could pose a serious risk to dairy herds. Thus, strict surveillance for protothecal mastitis is urgently needed and sanitary conditions regarding the environment and milk collection are essential because of the lack of effective treatment options.

Real-world effectiveness and safety of sofosbuvir plus daclatasvir with or without ribavirin for genotype 2 chronic hepatitis C in Taiwan.

BACKGROUND AND PURPOSE: Sofosbuvir (SOF) and daclatasvir (DCV) treatment achieves excellent efficacy and safety in treating chronic hepatitis C (CHC) with various genotypes. Real world experience of SOF/DCV regimen to treat genotype 2 CHC was scanty in Asia. This study aimed to evaluate the effectiveness and safety of SOF/DCV with or without ribavirin to treat genotype 2 CHC patients in real world practice in Taiwan. METHODS: Patients with genotype 2 CHC treated with 12-week of SOF/DCV or SOF/DCV/ribavirin were enrolled prospectively. Effectiveness was evaluated by sustained virological response (SVR) which was defined as undetectable hepatitis C virus (HCV) RNA at post-treatment week 12. Adverse events were recorded for safety analysis. RESULTS: In total of 32 patients were enrolled from October 2016 to June 2017. All were infected with genotype 2 HCV. Sixteen patients (50%) exhibited cirrhosis including 6 patients with decompensation. Regimens of SOF/DCV and SOF/DCV/ribavirin were used to treat 14 and 18 patients, respectively. SVR was achieved in all 31 patients (100%) who completed follow-up. Significantly higher levels of cholesterol (p = 0.013) and higher low density lipoprotein-cholesterol (p = 0.015) were exhibited after successful viral clearance. SOF/DCV/ribavirin regimen resulted in more adverse events, significantly higher bilirubin levels, and decline of hemoglobin during treatment than SOF/DCV regimen. Four patients with chronic kidney disease maintained renal function during treatment. Overall, SOF/DCV or SOF/DCV/ribavirin treatment was well tolerated. CONCLUSION: SOF/DCV with or without ribavirin is highly effective and safe for patients with genotype 2 HCV infection in real-world experience in Taiwan.

[A phase II, single-arm, open-label, multicenter clinical study to evaluate the efficacy and safety of sofosbuvir combined with ribavirin in patients with genotype 2 chronic hepatitis C virus infection].

Objective: To evaluate the efficacy and safety of sofosbuvir (Nanjing Zhengda Tianqing Pharmaceutical Co., Ltd.) combined with ribavirin in patients with genotype 2 chronic hepatitis C virus infection. Methods: Treatment-naïve or treatment experienced genotype 2 chronic hepatitis C patients from sixteen research centers of China were screened. All subjects received once-daily dose of sofosbuvir (400 mg) combined with ribavirin (body weight < 75 kg, 1 000 mg/day, 400 mg in the morning and 600 mg in the evening; body weight > 75 kg, 1 200 mg/d, 600 mg in the morning and 600 mg in the evening) for 12 weeks. Patients were followed-up for a period of 12 weeks after discontinuation of treatment. Continuous variables were expressed as mean ± standard deviation. The proportion of subjects with virologic response at different follow-up time points and 95% confidence intervals were estimated by maximum likelihood ratio and Clopper-Pearson interval. Results: 132 cases with genotype 2 chronic hepatitis C virus infection from sixteen research centers of China were included, 12 cases of whom were associated with cirrhosis, and the remaining 120 cases were not associated with cirrhosis. One hundred and thirty-one cases completed the study, and one patient lost to follow-up at week 4 after the end of treatment. The sustained virological response rate was 96.2% (95% confidence interval: 92.37% - 99.16%) after 12 weeks of drug withdrawal. Virological relapse occurred in four cases. Of the 132 subjects enrolled in the study, 119 (90.2%) reported 617 adverse events during treatment, of which 359 (76.5%) were TEAE related to sofosbuvir and/or ribavirin. There were nine TEAEs of grade 3 and above, and six cases (4.5%) of them had six severe adverse events. Only one serious adverse event was associated with sofosbuvir and ribavirin (unstable angina pectoris). There were no adverse events leading to drug discontinuation or death. Conclusion: Sofosbuvir combined with ribavirin has a high SVR rate in the treatment of genotype 2 chronic hepatitis C virus infection, and most of the adverse events occurred were mild with acceptable safety profile.

Resistance characterization of hepatitis C virus genotype 2 from Japanese patients treated with ombitasvir and paritaprevir/ritonavir.

Treatment of HCV genotype (GT) 2-infected Japanese patients with paritaprevir (NS3/4A inhibitor boosted with ritonavir) and ombitasvir (NS5A inhibitor) without ribavirin for 12 weeks in the phase 2 study M12-536, and with ribavirin for 16 weeks in phase 3 study GIFT II resulted in SVR rates of 72.2% to 91.5%. Overall, 11 out of 125 patients with GT2a and 37 out of 79 patients with GT2b infection experienced virologic failure. The prevalence of baseline polymorphisms in NS3 and NS5A and their the impact on treatment outcome, as well as the development of viral resistance in GT2-infected patients experiencing virologic failure were evaluated by HCV NS3 and NS5A population and clonal sequence analyses. Baseline polymorphisms in NS3 that confer resistance to paritaprevir were rare in both GT2a- and GT2b-infected patients, while baseline polymorphisms in NS5A that confer resistance to ombitasvir were detected in 11.2% and 14.1% of the GT2a- and GT2b-infected patients, respectively. There was no significant impact of baseline polymorphisms on treatment outcome in Japanese patients. The most common treatment-emergent substitutions at the time of virologic failure occurred at amino acid positions 168 in NS3 and 28 in NS5A in both GT2a- and GT2b-infected patients. Although there was a higher rate of virologic failure in patients with GT2b infection, the resistance analyses presented in this report support the conclusion that testing for baseline resistance-associated polymorphisms is not warranted for HCV GT2-infected patients treated with a regimen of ombitasvir/paritaprevir/ritonavir + ribavirin for 16 weeks.

Predictors of treatment efficacy and liver stiffness changes following therapy with Sofosbuvir plus Ribavirin in patients infected with HCV genotype 2.

While the combination therapy of ribavirin (RBV) and sofosbuvir (SOF) is effective in genotype 2 HCV infection, the predictors of treatment efficacy and posttreatment changes in α-fetoprotein (AFP) and liver stiffness (markers of hepatocellular carcinoma), remain unclear. In this study, 302 patients with chronic HCV genotype 2 infection were treated with SOF (400 mg) plus RBV (400-1000 mg; based on body weight) for 12 weeks. We evaluated the efficacy and safety of treatment, as well as measured serum AFP, liver stiffness, and controlled attenuation parameter (CAP, a surrogate marker of steatosis) at baseline and within 48 weeks of treatment completion. The intention-to-treat analysis showed a sustained virological response (SVR) rate of 95.7%. None of the patients discontinued treatment due to side effects. Multivariate analysis identified pretreatment (no treatment with interferon), level of AFP (AFP; <10 µg/L), and RBV/body weight (BW) ratio (≥9.0 mg/kg) as independent predictors of SVR. The SVR rate in patients with two predictors of poor response (AFP ≥10 µg/L and RBV/BW ratio <9.0 mg/kg) was significantly lower than in other patients. In the SVR group, posttreatment AFP level and liver stiffness were significantly lower than at baseline. CAP tended to be higher after treatment than at baseline in all patients. SOF plus RBV combination therapy achieved a high SVR rate and was safe in HCV genotype 2 infected patients. Treatment reduced AFP levels and improved liver stiffness, but increased CAP.