Pharmacokinetics and enhanced PKR response in patients with chronic hepatitis C treated with pegylated interferon alpha-2b and ribavirin

This study investigated the molecular and pharmacokinetic mechanisms of the enhanced antiviral efficacy associated with pegylated interferon (PEG-IFN) alpha-2b and ribavirin. The study involved comparing the expression of serial double-stranded RNA-activated protein kinase (PKR) before and during treatment in 26 PEG-IFN alpha-2b and 26 conventional IFN alpha-2b recipients matched for age, body weight and dose of ribavirin. The pharmacokinetics of PEG-IFN alpha-2b and ribavirin was analysed in 15 of the 26 PEG-IFN recipients. There was a rapid increase in PKR expression in both treatment groups, although expression from day 2 onwards was maintained at a significantly higher level in the PEG-IFN recipients (P < 0.05). C(max) of PEG-IFN occurred 12-48 h after the initial administration, with t(1/2) and C(min) being 49 h and 190 pg/mL, respectively. In contrast to ribavirin, accumulation of PEG-IFN was minimal. There was no association between serum PEG-IFN and ribavirin levels and virological response. Although baseline expression of PKR before treatment was marginally higher in nonresponders (NRs), from day 2 onwards, sequential PKR expression in response to PEG-IFN was higher in sustained viral responders compared with the NRs (P < 0.05). Significant correlations were found between kinetics of PKR expression and viral decline rates in each phase of hepatitis C virus dynamics (first phase, r = 0.67, P = 0.0006; second phase, r = 0.67, P = 0.001). In conclusion, improvement in pharmacokinetics following pegylation led to higher intracellular PKR expression, which was associated with enhanced virological efficacy of PEG-IFN-based combination therapy. The concentrations of both ribavirin and PEG-IFN alpha-2b were not associated with viral response and PKR expression.     

丙型肝炎防治指南(2015年更新版)

为规范丙型肝炎的预防、诊断和抗病毒治疗,中华医学会肝病学分会和感染病学分会根据丙型肝炎病毒(HCV)感染的特点、国内外最新的循证医学证据和药物的可及性,于 2015 年组织国内有关专家修订了《丙型肝炎防治指南》. 完善的病毒学检测是慢性 HCV 感染筛查、监测、诊断和治疗的基础.根据我国社会和经济发展情况,还需要积极发展适宜于资源有限地区HCV RNA 定量和 HCV 基因分型的检测试剂.政府、社会组织、学术团体、制药企业共同努力,以达到新型抗病毒治疗的可及和可负担.     

Low prevalence of hepatitis C virus infection in patients with auto-immune hepatitis type 1

Hepatitis C virus (HCV) antibodies were measured in 28 patients with auto-immune hepatitis type 1 using six different assay kits, three for C100–3 antibody and three for second generation HCV antibody, and two confirmatory tests to determine the prevalence of HCV infection in auto-immune hepatitis. These patients were confirmed to have human leucocyte antigen DR 4 or 2 which is susceptible to auto-immune hepatitis in Japanese. Of the 28 patients, four (14.3%) were positive for HCV antibody in all assays and reacted positively in at least one of the two confirmatory tests, indicating a true positive finding. Eight were positive for HCV antibody only by the Ortho ELISA kit and were negative in both confirmatory tests. The cut-off level for these results was low and became negative soon after the patients received corticosteroid treatment. Thus, these eight patients are presumed to be false-positive reactors. Hepatitis C virus RNA was detected in the serum of two of the four patients with HCV antibody and in none of 24 patients without HCV antibody. No significant difference was observed between the patients with and without HCV antibody in terms of clinical background, liver function tests and auto-antibodies. Our results showed that the prevalence of a past or present HCV infection in patients with auto-immune hepatitis in Japan is low; thus, auto-immune hepatitis is thought to be distinct from hepatitis type C. However, it is also suggested that HCV infection can potentially trigger auto-immune hepatitis.     

Hepatitis C virus infection in the human immunodeficiency virus infected patient

Human immunodeficiency virus(HIV)and hepatitis C virus(HCV)share the same transmission routes;therefore,coinfection is frequent.An estimated 5-10 million individuals alone in the western world are infected with both viruses.The majority of people acquire HCV by injection drug use and,to a lesser extent,through blood transfusion and blood products.Recently,there has been an increase in HCV infections among men who have sex with men.In the context of effective antiretroviral treatment,liver-related deaths are now more common than Acquired Immune Deficiency Syndromerelated deaths among HIV-HCV coinfected individuals.Morbidity and mortality rates from chronic HCV infection will increase because the infection incidence peaked in the mid-1980s and because liver disease progresses slowly and is clinically silent to cirrhosis and end-stage-liver disease over a 15-20 year time period for 15%-20%of chronically infected individuals.HCV treatment has rapidly changed with the development of new direct-acting antiviral agents;therefore,cure rates have greatly improved because the new treatment regimens target different parts of the HCV life cycle.In this review,we focus on the epidemiology,diagnosis and the natural course of HCV as well as current and future strategies for HCV therapy in the context of HIV-HCV coinfection in the western world.     

Significance of Prior Hepatitis B Virus Infection in the Development of Hepatocellular Carcinoma in Patients with Chronic Hepatitis C

To clarify the clinical significance of prior hepatitis B virus (HBV) infection in the development of C-viral hepatocellular carcinoma (HCC), we conducted two studies: (1) Two hundred thirty-four patients with C-viral HCC and 320 patients with C-viral chronic liver disease without HCC admitted to our hospital between 1990 and 1994 were analyzed for the association of hepatitis B core antibody (HBcAb) positivity with HCC by multivariate logistic regression analysis, and this revealed HBcAb positivity as an independent risk factor for development of HCC adjusted for age and sex. (2) Four hundred fifty-nine patients with biopsy-proven hepatitis C virus-related chronic liver disease between 1986 and 1998 were enrolled in the cohort study and followed for the development of HCC. During an average follow-up of 6.6 ± 3.3 years, HCC developed in 63 patients, 37 of 160 patients positive for HBcAb and 26 of 299 patients negative for HBcAb. Multivariate Cox proportional regression analysis showed that the incidence of HCC increased by age, advanced stage of liver fibrosis, mean alanine aminotransferase value of more than 80 IU/liter, and positivity of HBcAb. Sustained virological responders after interferon therapy revealed a reduced risk for HCC development. In conclusion, prior HBV infection was shown to be one of the independent risk factors for development of HCC in C-viral chronic liver disease.     

Hepatitis C virus clearance is prominent in women in an endemic area

BACKGROUND: The clinical and virological backgrounds of cases with previous hepatitis C virus (HCV) infection (positive for HCV antibody (anti-HCV) and HCV-RNA negative) in an HCV endemic area were examined to identify factors related to the clearance of HCV. METHODS: The study population comprised 3117 inhabitants, 1037 male and 2080 female, from an HCV endemic area. Hepatitis C virus antibody was detected by a passive haemagglutination test. The HCV-RNA and the HCV genotype were detected by using the polymerase chain reaction method. The HCV serotype was determined by enzyme immunoassay by using the peptides of the core region. RESULTS: Twenty-two per cent of the inhabitants were positive for anti-HCV, with males and the elderly having a significantly higher antibody titre (P < 0.01) than youths and females. Hepatitis C virus-RNA was detected in 78% of the HCV antibody-positive cases. The rate of HCV-RNA positivity was significantly higher in males than in females (P < 0.01). No relationship was found between HCV-RNA positivity and age. The HCV genotype 1b was the predominant genotype among the HCV-RNA-positive cases. Mixed genotypes (1b + 2a) were observed in 12% of cases, primarily in elderly males and females. In cases with previous HCV infection, serotype 1 was the most common serotype, and there appeared to be no relationship between the distribution of HCV serotypes and age and gender. There was a female predominance with regard to previous HCV infection, but not to being HCV carriers (P < 0.01). CONCLUSIONS: Gender, not HCV genotype, is the primary factor influencing HCV clearance.     

Viral and host factors in the prediction of response to interferon-α therapy in chronic hepatitis C after long-term follow-up

Acute infection with hepatitis C virus (HCV) develops into a chronic hepatitis in about 50–70% of patients. Treatment of these patients with interferon-α (IFN-α) results in a sustained long-term response in only 15–20% but causes numerous unwanted side-effects in a higher percentage of patients. The aim of our study was to define host or viral parameters that would allow identification of responders and non-responders to IFN-α prior to the onset of treatment. We studied a group of 87 patients suffering from chronic hepatitis C who were treated with IFN-α. After long-term follow-up, 18 patients (21%) showed a sustained response to IFN-α therapy (normalization of serum transaminases and loss of viral RNA from serum) for up to 7 years after therapy had ceased. By univariate and multivariate analyses, no host factors were found to be predictive of response to therapy. Neither the degree of inflammation or fibrosis in liver biopsy samples obtained before treatment nor immunogenetic factors (major histocompatibility complex II haplotype and tumour necrosis factor-α promoter polymorphism) were associated with response to therapy. In contrast, viral parameters showed a strong association with response to therapy. HCV genotype 3 was found significantly more frequently in responders (P = 0.034), and mean HCV RNA concentration was lower in responders (3.1 × 10⁴) than in non-responders (2.5 × 10⁵) (P = 0.01). By multivariate analysis, both HCV genotype and HCV RNA concentration were independent predictors of response to therapy. However, exact prediction of response to treatment for an individual patient was not possible on the basis of pretreatment viral RNA concentration or viral genotype. The best association with response to therapy was found to be clearance of HCV RNA from serum 3 months after the start of treatment (32 of 34 partial and sustained responders vs 0 of 53 non-responders; P = 0.001). In conclusion, determination of pretreatment viral factors, but not host factors, was significantly correlated with treatment response but did not give an accurate prediction for patients, whereas clearance of HCV RNA from serum after 3 months of therapy was predictive of response to therapy.     

HBV感染者HCV的重叠感染关系研究

目的 研究HBV感染患者中HCV的重叠感染状况及其相互关系。 方法 采用ELISA法对767例HBV感染患者同步检测HBV和HCV血清标志物,对可疑HCV感染但抗HCV阴性和/或抗-HCV阳性患者血清,采用PCR法检测HCV-RNA。 结果 HCV重叠感染率为4.82％,且在各类乙肝患者中存在非常显著差异(P<0.01);HBV/HCV感染组重症肝炎的发生率显著高于非HCV感染组(P<0.01);HBV/HCV感染组HBsAg阳性率显著低于单纯HBV感染组(P<0.05);HBV/HCV感染组HCV-RNA阳性率显著低于单纯HCV感染组(P<0.05)。 结论 HCV重叠感染与乙肝患者的发病、病情加重及重症肝炎的发生相关;HCV可抑制或中止HBsAg携带状态,但这种作用远不如对病情的加重作用重要;同时HBV对HCV的复制亦存在抑制作用。     

Clinical characteristics and distribution of genotypes of TT virus infection in a hepatitis C virus-hyperendemic township of a hepatitis B virus-endemic country (Taiwan)

BACKGROUND: The prevalence of TT virus (TTV) viremia, without definite clinical significance, has been reported to be higher among chronic hepatitis C patients. The status and clinical characteristics of TT virus (TTV) infection and distribution of TTV genotypes in a hepatitis C virus (HCV) hyperendemic township (Masago community) in a hepatitis B virus (HBV) endemic country (Taiwan) were investigated. METHODS: Sera from 100 Masago residents were tested for alanine aminotransferase (ALT) and markers of HBV, HCV and GB virus C/hepatitis G virus (GBV-C/HGV) and TTV-DNA. Sera of 250 blood donors as a control group were tested for TTV-DNA. Sera of Masago residents and blood donors with positive TTV-DNA were directly sequenced, and phylogenetic analyses were performed subsequently. RESULTS: The prevalences of TTV viremia in different age groups among individuals from Masago were significantly higher than that among blood donors. In regard to the subtypes of TTV, 23, seven, two, eight, one, six and one isolate were related to the genotypes 1a, 1b, 2a, 2b, 3, 4 and 5, respectively, from Masago and 21, 14, one, nine and three isolates were related to the genotypes 1a, 1b, 2a, 2b, and 4, respectively, from donors. No clinical or virological factor was associated with TTV viremia or TTV genotypes. CONCLUSIONS: TT Virus prevalence was higher among HCV hyperendemic township residents than blood donors with similar genotype distributions (genotype 1 was the most prevalent) in Taiwan. Neither TTV viremia nor a particular genotype was associated with HBV, HCV or GBV-C/HGV infection and abnormal ALT levels.     

Pretreatment assessment and predictors of hepatitis C virus treatment in US veterans coinfected with HIV and hepatitis C virus

The US Department of Veterans Affairs (VA) cares for many human immunodeficiency virus/hepatitis C virus (HIV/HCV)-coinfected patients. VA treatment recommendations indicate that all HIV/HCV-coinfected patients undergo evaluation for HCV treatment and list pretreatment assessment tests. We compared clinical practice with these recommendations. We identified 377 HIV/HCV-coinfected veterans who began HCV therapy with pegylated interferon and ribavirin and 4135 HIV/HCV-coinfected veterans who did not but were in VA care at the same facilities during the same period. We compared laboratory and clinical characteristics of the two groups and estimated multivariate logistic regression models of receipt of HCV treatment. Overall, patients had high rates of receipt of tests necessary for HCV pretreatment assessment. Patients starting HCV treatment had higher alanine aminotransferase (ALT), lower creatinine, higher CD4 counts and lower HIV viral loads than patients not starting HCV treatment. In the multivariate model, positive predictors of starting HCV treatment included being non-Hispanic whites, having higher ALTs, lower creatinines, higher HCV viral loads, higher CD4 counts, undetectable HIV viral loads and receiving HIV antiretrovirals. A history of chronic mental illness and a history of hard drug use were negative predictors. Most HIV/HCV-coinfected patients received the necessary HCV pretreatment assessments, although rates of screening for hepatitis A and B immunity can be improved. Having well-controlled HIV disease is by far the most important modifiable factor affecting the receipt of HCV treatment. More research is needed to determine if the observed racial differences in starting HCV treatment reflect biological differences, provider behaviour or patient preference.     

Hepatitis G virus RNA and its relation to hepatitis C infection in adult haemophilic patients

The prevalence of hepatitis C virus (HCV) infection and hepatitis G virus (HGV) RNA were studied in 50 adult haemophilic patients who had received commercial clotting factors prior to 1980. HGV RNA was detectable in 6/50 patients (12%); 49/50 (98%) had antibody to HCV and 40/49 (82%) of these were viraemic with detectable HCV RNA; 5/6 patients with detectable HGV RNA had co-existing HCV infection and viraemia. The HGV PCR products from all six patients were directly sequenced and all were shown to be similar to that of HGV but more diverse from that of GB virus C. One patient who had persistent abnormal liver function tests had detectable HGV RNA but no evidence of hepatitis B or C. The presence of HGV RNA in the absence of hepatitis B and C infection indicates that this virus is capable of independent transmission. Independent response to interferon was demonstrated in one patient with co-infection who lost HGV but not HCV after interferon therapy.     

Prevalence and clinical significance of GB virus type C/hepatitis G virus coinfection in patients with chronic hepatitis C undergoing antiviral therapy

Summary. Coinfection with GBV‐C/HGV in patients with chronic hepatitis C (CHC) may influence clinical course and response rates of antiviral therapy. Aim of the study was to investigate the prevalence of GBV‐C/HGV/HCV coinfection and its influence on outcome of interferon/ribavirin combination therapy. Three hundred and four patients with CHC [m/f = 211/93, age: 42 (18–65)] were investigated. HGV RNA detection was performed by polymerase chain reaction prior to and 6 months after the end of antiviral therapy. HGV/HCV coinfection could be identified in 37/304 (12.2%) patients with intravenous drug abuse as the most common source of infection (N = 21, (56.8%)). The predominant HCV genotype in coinfected individuals was HCV‐3a (HCV‐3a: 51.4%, HCV‐1: 37.8%, HCV‐4: 10.8%). HGV coinfection was more prevalent in patients infected with HCV‐3 compared to HCV‐1 or HCV‐4 [19/45 (42.2%) vs 14/185 (7.6%) vs 4/52 (7.7%), P < 0.01]. Patients with HGV/HCV coinfection were younger [35 (18–56) vs 43 (19–65), years; P < 0.01], and advanced fibrosis (F3‐F4) was less frequent (22.2%vs 42.9%, P < 0.05). A sustained virological response was achieved more frequently in HGV/HCV coinfected patients [26/37 (70.3%)] than in monoinfected patients [120/267 (44.9%), P < 0.01]. HGV RNA was undetectable in 65.7% of the coinfected patients at the end of follow‐up. Intravenous drug abuse seems to be a major risk factor for HGV coinfection in patients with chronic hepatitis C. Coinfection with HGV does not worsen the clinical course of chronic hepatitis C or diminish response of HCV to antiviral therapy. Interferon/ribavirin combination therapy also clears HGV infection in a high proportion of cases.