Polymorphisms of the core, NS3, and NS5A proteins of hepatitis C virus genotype 1b associate with development of hepatocellular carcinoma.

UNLABELLED: Hepatocellular carcinoma (HCC) is one of the common sequelae of hepatitis C virus (HCV) infection. It remains controversial, however, whether HCV itself plays a direct role in the development of HCC. Although HCV core, NS3, and NS5A proteins were reported to display tumorigenic activities in cell culture and experimental animal systems, their clinical impact on HCC development in humans is still unclear. In this study we investigated sequence polymorphisms in the core protein, NS3, and NS5A of HCV genotype 1b (HCV-1b) in 49 patients who later developed HCC during a follow-up of an average of 6.5 years and in 100 patients who did not develop HCC after a 15-year follow-up. Sequence analysis revealed that Gln at position 70 of the core protein (core-Gln(70) ), Tyr at position 1082 plus Gln at 1112 of NS3 (NS3-Tyr(1082) /Gln(1112) ), and six or more mutations in the interferon/ribavirin resistance-determining region of NS5A (NS5A-IRRDR≥6) were significantly associated with development of HCC. Multivariate analysis identified core-Gln(70) , NS3-Tyr(1082) /Gln(1112) , and α-fetoprotein (AFP) levels (>20 ng/L) as independent factors associated with HCC. Kaplan-Meier analysis revealed a higher cumulative incidence of HCC for patients infected with HCV isolates with core-Gln(70) , NS3-Tyr(1082) /Gln(1112) or both than for those with non-(Gln(70) plus NS3-Tyr(1082) /Gln(1112) ). In most cases, neither the residues at position 70 of the core protein nor positions 1082 and 1112 of the NS3 protein changed during the observation period. CONCLUSION: HCV isolates with core-Gln(70) and/or NS3-Tyr(1082) /Gln(1112) are more closely associated with HCC development compared to those with non-(Gln(70) plus NS3-Tyr(1082) /Gln(1112) ).

In vivo interferon system assessed by 2'-5' oligoadenylate synthetase activity in chronic hepatitis C virus patients treated with pegylated interferon and ribavirin.

AIM: 2',5' oligoadenylate synthetase (2-5AS), an enzyme induced by interferon, is an accurate indicator of the antiviral effect of interferon. We measured it during pegylated interferon based therapies in patients with chronic hepatitis C virus (HCV) in order to determine the dynamics of antiviral status in vivo and the relationship between the response to exogenous interferon and the outcome of therapy. METHODS: A total of 160 patients with chronic HCV were treated with pegylated interferon alfa 2a or 2b or non-pegylated interferon, with or without ribavirin. Serum 2-5AS activity was measured by radioimmunoassay assay kits every 2 weeks. RESULTS: In 60 patients treated with pegylated interferon alfa 2a or 2b, 2-5AS levels increased to 7-40 times (average 235 pmol/dL) above the pretreatment levels (30 pmol/dL), which were significantly higher than the levels during non-pegylated interferon therapy. Ribavirin did not enhance 2-5AS levels. 2-5AS levels between sustained virological response (SVR) and non-SVR, including null responders to pegylated interferon plus ribavirin therapy were not significantly different. CONCLUSION: 2-5AS levels were significantly higher in patients treated with pegylated interferon than in those treated with non-pegylated interferon, suggesting that pegylated interferon is more potent at inducing interferon response genes resulting in an improved antiviral effect. Ribavirin did not appear to be related to interferon response gene induction.

Virological response in patients with hepatitis C virus genotype 1b and a high viral load: impact of peginterferon-alpha-2a plus ribavirin dose reductions and host-related factors.

BACKGROUND AND OBJECTIVE: In Japan the prevalence of the hepatitis C virus (HCV) antibody is highest in the elderly population. Therefore, it is important for elderly patients to undergo interferon (IFN) therapy. In patients with HCV genotype 1b and a high viral load, the sustained virological response (SVR) rate is lower in older compared with younger patients receiving combination antiviral therapy. In addition, inadequate adherence to combination therapy is often seen in elderly patients, and is associated with reduced response rates. The aim of this retrospective analysis was to evaluate the effects of host-related factors (i.e. sex, age, baseline HCV RNA level, bodyweight and fibrosis stage) and peginterferon (PEG IFN)-alpha-2a plus ribavirin dose reductions on SVR rates. METHODS: A total of 192 treatment-naive patients with a HCV genotype 1b infection and a high viral load were included in the analysis. Patients had been enrolled into a phase III trial of 48 weeks of treatment with PEG IFN-alpha-2a plus ribavirin or PEG IFN-alpha-2a plus placebo. All patients were evaluated for effect of drug exposure on SVR. In addition, the impact of host-related factors or dose reductions on SVR was assessed. RESULTS: Approximately 30% of patients were considered elderly (> or =60 years of age). The overall SVR rate was significantly higher in patients treated with combination therapy versus monotherapy (59.4% vs 24.0%, p < 0.001). Attainment of an SVR following combination therapy was not influenced by any factor evaluated in the analysis, although elderly males were associated with decreased SVR rates. Younger age (odds ratio [OR] 1.081; 95% CI 1.125, 1.034; p = 0.0009), lower baseline HCV RNA levels (OR 1.003; 95% CI 1.006, 1.001; p = 0.006) and a severe fibrosis stage (F3/4) [OR 6.194; 95% CI 1.037, 37.000; p = 0.0455] significantly increased the likelihood of achieving an SVR with monotherapy. In the combination therapy group, patients maintaining a full dosage schedule of PEG IFN-alpha-2a and ribavirin and those requiring dose reductions of either study drug had similar SVR rates (64.5% vs 61.9%). However, the SVR rate was reduced to 33.3% among patients who discontinued combination therapy. Three out of the 31 patients who received the full dosage schedule were elderly patients. In addition, of the 15 patients who discontinued combination therapy, three were <50 years of age and six were > or =60 years of age. The SVR rate was reduced in patients with cumulative PEG IFN-alpha-2a and ribavirin doses of <60%; the majority of these patients were elderly. CONCLUSION: The attainment of an SVR following PEG IFN-alpha-2a plus ribavirin combination therapy was not influenced by any of the host-related factors evaluated in this analysis, although elderly males were associated with a decreased SVR rate. Younger age, male sex and lower baseline HCV RNA levels significantly increased the likelihood of achieving an SVR with monotherapy. In addition, dose reductions appeared to have a negative impact on SVR in elderly patients. Therefore, it is important to minimize PEG IFN-alpha-2a and ribavirin dose reductions by effectively managing treatment-related adverse events in elderly patients.

Early reduction of infected hepatocytes by activated immunity at the time of interferon withdrawal hepatitis followed by lamivudine administration resulted in higher seroconversion in hepatitis Be antigen-positive patients with chronic hepatitis B.

BACKGROUND: It has been found that the efficacy of lamivudine (LAM) therapy can be improved by preceding administration with a short course of corticosteroid that induces a flare of the disease upon its withdrawal. Because of the side effects of corticosteroid, we tested the effect of a short course of interferon (IFN) as the primer instead of prednisolone, which was followed by LAM when the hepatitis flare occurred. The incidence of LAM resistance mutations and the effect of core promoter and precore mutations on the durability of the responses were also studied. METHODS: Patients treated with interferon (IFN)-LAM therapy (n=73) were compared to those treated with IFN alone (n=117). The IFN-LAM group received IFN-alpha MU/day, t.i.w. for a 3-month period. LAM (10mg/day during 1 year) was started when IFN withdrawal hepatitis occurred during 2-10 months after stopping IFN. The LAM-resistant, core promoter, and precore mutations were examined by sequencing. RESULTS: (1) The IFN-LAM group developed exacerbated hepatitis following IFN withdrawal in 63 patients before starting LAM therapy. The seroconversion (SC) rate was significantly higher in the IFN-LAM group than in the IFN-alone group (61% vs 26%, P=0.0001). (2) The LAM resistance mutation rate was 31% at 1 year after initiating LAM therapy. (3) In a stepwise discriminant-function analysis, decreased level of HBeAg determined at 4 weeks after LAM administration and increased level of HBeAb before the start of LAM administration contributed significantly on seroconversion to anti-HBe (P = 0.0073 and 0.004, respectively). (4) The reappearance rate of HBeAg within 6 months after the therapy (relapse) was 33% in the IFN-LAM group and 10% in the IFN-alone group. The prevalence of core promoter and precore mutations did not change before and after the therapy, nor did these mutations correlate with the relapse after stopping IFN-LAM therapy. CONCLUSIONS: (1) Our findings suggest that early reduction of infected hepatocytes expressed by HBeAg by LAM may contribute to a high SC rate of IFN-LAM therapy. (2) The emergence of LAM-resistant mutations was similar to the previously reported rate, and neither core promoter nor precore mutations correlated with relapse of seroconverters after IFN-LAM withdrawal.

The predictive value of liver fibrosis in determining the effectiveness of interferon and lamivudine therapies for chronic hepatitis B.

BACKGROUND: To determine the best indicator of the effective use of interferon and lamivudine for the treatment of hepatitis B e antigen-positive chronic hepatitis, we retrospectively analyzed histologic and virologic status in 200 patients who were treated with interferon and 45 patients who were treated with lamivudine. METHODS: Histological grading and staging scores were determined by international criteria and the METAVIR scoring system. The YMDD motif associated with lamivudine resistance was analyzed by the sequencing of hepatitis B virus (HBV) DNA. RESULTS: Of 200 interferon-treated patients, 62 (31%) seroconverted to anti-hepatitis B e (anti-HBe). Multivariate analysis showed that the significantly important predictors of response were a higher grading score (P = 0.0056) and lower staging score (P = 0.0010). Twenty (44%) of the 45 lamivudine-treated patients seroconverted to anti-HBe, and multivariate analysis showed that the significantly important predictors of response were a higher alanine aminotransferase (ALT) level (P = 0.0034) and lower hepatitis B e antigen levels ( P = 0.0128). YMDD mutations occurred during therapy in 12 patients (27%). The significantly important predictor of the development of mutation was a higher staging score (P = 0.0226). CONCLUSIONS: Both interferon and lamivudine were effective for patients with high ALT levels, but interferon's efficacy appeared to be limited by the degree of fibrosis. Lamivudine appeared to be effective irrespective of the degree of fibrosis, but YMDD mutations seemed to develop sooner in patients with advanced liver fibrosis.

Peginterferon alpha-2a (40 KD) plus ribavirin for the treatment of chronic hepatitis C in Japanese patients.

BACKGROUND: The efficacy and safety of peginterferon alpha-2a (40 KD) (peg-IFNalpha-2a) plus ribavirin has not been reported for Japanese patients with chronic hepatitis C. The aim of this study was to evaluate this combination in treatment-naïve patients and in non-responders or relapsers to interferon monotherapy. METHODS: Overall, 201 treatment-naïve patients with hepatitis C virus (HCV) genotype-1b were randomly assigned to 180 microg peg-IFNalpha-2a once-weekly plus ribavirin 600-1000 mg/day or peg-IFNalpha-2a plus placebo for 48 weeks. Additionally, peg-IFNalpha-2a plus ribavirin was administered for 48 weeks to 100 non-responders or relapsers (85% genotype-1) to previous interferon monotherapy. RESULTS: A sustained virological response (SVR) was attained among significantly more treatment-naïve patients receiving combination therapy than monotherapy (61% vs 26%, P < 0.001). For patients with high baseline HCV RNA, the SVR rate was 59% with peg-IFNalpha-2a plus ribavirin versus 24% with peg-IFNalpha-2a monotherapy. Among non-responders or relapsers to previous interferon monotherapy, 54% attained an SVR. Adverse events were generally mild, and discontinuations rates due to adverse events or laboratory abnormalities were low. CONCLUSION: In Japanese patients, peg-IFNalpha-2a plus ribavirin provided significant improvement in SVR rates compared with peg-IFNalpha-2a alone in treatment-naïve patients, and was effective as re-treatment for non-responders or relapsers to previous treatment with interferon monotherapy.

Genetic changes in hypervariable region 1 as a possible mechanism for biochemical responders with interferon therapy.

AIM: Approximately 10% of chronic hepatitis C patients who were treated with interferon have a sustained normalization of aminotransferase levels after interferon therapy without HCV RNA clearance. We investigated genetic change in hypervariable region 1 (HVR 1) to see if the mutation in this region is responsible for their sustained biochemical response and relapse thereafter. A total of 250 patients with chronic hepatitis C who were treated with interferon were studied for 8 to 11 years post therapy. Of these, 26 were biochemical responders (BR) whose ALT remained normal without viral clearance for more than 6 months after IFN therapy. HVR 1 was examined by direct sequencing of the PCR products, and found that no significant HVR 1 differences were observed in samples obtained pretreatment, posttreatment or during flares from these patients, suggesting that mutations in this region were not responsible for either the persistence of the HCV RNA or for the ALT relapses thereafter.