Twice-daily administration of interferon-beta for chronic hepatitis C is not superior to a once-daily regimen

Human Ebola virus infection in West Africa: a review of available therapeutic agents that target different steps of the life cycle of Ebola virus

The recent outbreak of the human Zaire ebolavirus (EBOV) epidemic is spiraling out of control in West Africa. Human EBOV hemorrhagic fever has a case fatality rate of up to 90%. The EBOV is classified as a biosafety level 4 pathogen and is considered a category A agent of bioterrorism by Centers for Disease Control and Prevention, with no approved therapies and vaccines available for its treatment apart from supportive care. Although several promising therapeutic agents and vaccines against EBOV are undergoing the Phase I human trial, the current epidemic might be outpacing the speed at which drugs and vaccines can be produced. Like all viruses, the EBOV largely relies on host cell factors and physiological processes for its entry, replication, and egress. We have reviewed currently available therapeutic agents that have been shown to be effective in suppressing the proliferation of the EBOV in cell cultures or animal studies. Most of the therapeutic agents in this review are directed against non-mutable targets of the host, which is independent of viral mutation. These medications are approved by the Food and Drug Administration (FDA) for the treatment of other diseases. They are available and stockpileable for immediate use. They may also have a complementary role to those therapeutic agents under development that are directed against the mutable targets of the EBOV.

Interferon for interferon nonresponding and relapsing patients with chronic hepatitis C

BACKGROUND

The widely-accepted treatment outcome for chronic hepatitis C is the sustained viral response (that is, no measurable viral RNA in blood six months after treatment). However, this surrogate outcome (as well as the previously employed biochemical and histologic ones) has never been validated. This situation exists because there are very few randomized clinical trials that have used clinical events (mortality or manifestations of decompensated cirrhosis) as outcomes, because those clinical events only occur after many years of infection. Patients in whom initial therapy fails to produce sustained viral responses do become potential candidates for retreatment; some of these individuals are not candidates for ribavirin or protease inhibitors and consideration could be given to retreatment with interferon alone.

OBJECTIVES

To assess the benefits and harms of interferon monotherapy retreatment in chronic hepatitis C patients and to validate the currently employed surrogate outcomes in this group of patients.

SEARCH METHODS

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until 16 August 2012.

SELECTION CRITERIA

Randomized trials comparing interferon versus placebo or no treatment in chronic hepatitis C nonresponders and relapsers to previous interferon.

DATA COLLECTION AND ANALYSIS

The primary outcomes were mortality (all-cause and hepatic), quality of life, and adverse events. Secondary outcomes were liver-related morbidity, sustained viral responses, biochemical responses, histologic improvements, and costs. We used both fixed-effect and random-effects model meta-analyses, reporting only the former if no difference existed.

MAIN RESULTS

Seven trials were identified. Two of them were at low risk of bias (the HALT-C and EPIC3 trials) and included 1676 patients. Both of these trials addressed the role of long-term low-dose pegylated interferon therapy in patients with severe fibrosis (demonstrated on liver biopsy) and were designed to assess the clinical outcomes. The remaining five trials included 300 patients and were at high risk of bias. Based on all trials reporting the outcomes, no significant difference was observed in either all-cause mortality (78/843 (9.3%) versus 62/867 (7.2%); risk ratio (RR) 1.30, 95% confidence interval (CI) 0.95 to 1.79; 3 trials) or hepatic mortality (41/532 (7.7%) versus 40/552 (7.2%); RR 1.07, 95% CI 0.70 to 1.63; 2 trials); however, when only the two trials at low risk of bias were combined, all-cause mortality was significantly higher in the recipients of the pegylated interferon (78/828 (9.4%) versus 57/848 (6.7%); RR 1.41, 95% CI 1.02 to 1.96) although trial sequential analysis could not exclude the possibility of random error. There was less variceal bleeding in the recipients of the interferon (4/843 (0.5%) versus 18/867 (2.1%); RR 0.24, 95% CI 0.09 to 0.67; 3 trials), although again trial sequential analysis could not exclude the presence of a type I error and the effect could not be confirmed in a random-effects model meta-analysis. No significant differences were seen with regard to the development of ascites, encephalopathy, hepatocellular carcinoma, or the need for liver transplantation. One trial reported quality of life data; the pain score was significantly worse in the recipients of the pegylated interferon. Adverse effects tended to be more common in the interferon recipients; the ones that were significantly more common included hematologic complications, infections, flu-like symptoms, and rash. The recipients of interferon had significantly more sustained viral responses (20/557 (3.6%) versus 1/579 (0.2%); RR 15.38, 95% CI 2.93 to 80.71; 4 trials) and a type I error was excluded by trial sequential analysis. The METAVIR activity score also improved (36/55 (65%) versus 20/46 (43.5%); RR 1.49, 95% CI 1.02 to 2.18; 2 trials). No significant differences were seen with regard to histologic fibrosis assessments.

AUTHORS' CONCLUSIONS

The clinical data were limited to patients with histologic evidence of severe fibrosis who were retreated with pegylated interferon. In this scenario, retreatment with interferon did not appear to provide significant clinical benefit and, when only the trials at low risk of bias were considered, retreatment for several years may even have increased all-cause mortality. Such treatment also produced adverse events. On the other hand, the treatment did result in improvement in some surrogate outcomes, namely sustained viral responses and histologic evidence of inflammation. Interferon monotherapy retreatment cannot be recommended for these patients. No clinical data are available for patients with less severe fibrosis. The sustained viral response cannot be used as a surrogate marker for hepatitis C treatment in this clinical setting with low sustained viral response rates and needs to be validated in others in which higher sustained viral response rates are reported.

Efficacy of the regimen using twice-daily β-interferon followed by the standard of care for chronic hepatitis C genotype 1b with high viral load

AIM

  In patients with refractory genotype 1b chronic hepatitis C with high viral loads, we retrospectively compared the efficacy of standard of care treatment (SOC: combined PEG-IFN-α-2b/ribavirin for 48 weeks) and a regimen in which 2 weeks of SOC induction was replaced by twice-daily β-interferon alone (IFN-β induction therapy).

METHODS

  Seventeen patients received the IFN-β induction therapy plus SOC (IFN-β induction group) and 13 patients received SOC alone (SOC group).

RESULTS

  In the IFN-β induction group and SOC group, early virological response (EVR) rates were 88.2% and 53.8%, respectively. The end of treatment rates were 100.0% and 92.3%, and sustained virological response (SVR) rates were 70.6% and 53.8%, respectively. By induction with IFN-β, even in refractory cases, the high virus negative conversion rate in the early treatment phase and actions of pegylated IFN-α-2b and ribavirin in the maintenance treatment phase led to an additive effect. In the analysis of contributing factors, only the achievement of EVR was associated with a significant difference in SVR (P = 0.0011). The univariate logistic regression analysis showed that only IFN-β treatment was associated with a significant difference in EVR (P = 0.0492, odds ratio = 6.248, 95% confidence interval = 1.026-40.252), whereas no significant factors were found in the multivariate analysis due to small samples.

CONCLUSION

  IFN-β induction therapy with higher EVR might be beneficial for protease inhibitor-refractory chronic hepatitis C patients.

Recombinant interferon-Beta-1alpha plus ribavirin for the treatment of chronic HCV infection: a prospective, randomized, comparative pilot study

BACKGROUND/AIMS

Interferon beta (IFN-beta) has been shown to have antiviral activity, and thus could be useful in treating viral infections. Therefore, we compared the efficacy and safety of recombinant IFN-beta (IFN-beta-1a) plus oral ribavirin versus interferon alpha (IFN-alpha) plus ribavirin therapy for the treatment of chronic hepatitis C (HCV).

METHODS

Twenty treatment-naïve patients were randomized into two equal-sized treatment groups. Both IFN-beta-1a (44 microg) and IFN-alpha (3 MIU) were given subcutaneously three times a week, while ribavirin was given orally at 1,000-1,200 mg/day. Patients were treated for 24 weeks and followed for an additional 24 weeks.

RESULTS

After 24 weeks of treatment, six (60%) and four patients (40%) in the IFN-beta-1a group and IFN-alpha groups, respectively, achieved viral clearance. The sustained virological response (SVR) at the end of the observation period was similar in both groups (40%). However, the baseline viral load was significantly higher (p=0.034) in the IFN-beta-1a group than in the IFN-alpha group, and there were more HCV genotype 1 patients in the IFN-beta-1a group (eight versus seven). The IFN-beta-1a group was associated with similar adverse events in terms of frequency and severity.

CONCLUSIONS

The SVR rate and safety profile were similar for the combination of IFN-beta-1a and ribavirin and that of IFN-alpha and ribavirin.

Interferon beta 1a versus interferon beta 1a plus ribavirin for the treatment of chronic hepatitis C in Chinese patients: a randomized, placebo-controlled trial

For chronic hepatitis C virus (HCV) infection, the effects of current therapies are limited. To evaluate the efficacy and safety of the interferon beta-1a (IFN beta-1a) versus IFN beta-1a plus ribavirin (RBV) combination on Chinese treatment-naïve patients with chronic hepatitis C, a randomized, placebo-controlled study was performed. A total of 26 naïve patients histologically confirmed to have chronic hepatitis C were double-blindly and randomly assigned to receive either IFN beta-1a 44 microg (12 MIU) (IFN beta-1a group) or placebo (placebo group) three times per week for 12 weeks. At the end of the 12 weeks of treatment, the patients who received IFN beta-1a continued to complete 24 weeks of treatment. Placebo non-responders were crossed over to IFN beta-1a plus RBV (1,000-1,200 mg/day) combination therapy (IFN beta-1a plus RBV group) for 24 weeks after 4 weeks washout. All patients were followed up for 24 weeks after the end of treatment. Sustained virological response (SVR) was defined as the absence of detectable HCV RNA in the serum both at the end of 24 weeks of treatment and at the end of 24 weeks of untreated follow-up. There were no differences in the clinical background between the groups before the initiation of treatment. At the end of the 12 weeks of double-blind therapy, HCV RNA was negative and undetectable in 10/11 patients (90.9%) in the IFN beta-1a group and none in the placebo group. The virological response rate (14/15, 93.3%) of the IFN beta-1a plus RBV group at week 12 after the initiation of therapy was similar to that of the IFN beta-1a group. SVR was observed in 5/11 (45.5%) of the IFN beta-1a group and 11/15 (73.3%) of the IFN beta-1a plus RBV group (P = 0.23). At the end of follow-up, a biochemical response was found in 5/11 patients in the IFN beta-1a group (45.5%) and 8/15 patients in the IFN beta-1a plus RBV group (53.3%, P = 1.00). Multiple logistic regression analysis confirmed that an HCV RNA load lower than 1.0x10(6) copies/ml was independently associated with SVR (OR 11.00; 95% CI 1.81-66.97; P = 0.003). The side effects were mild and similar in the two therapy groups. We conclude that IFN beta-1a alone or in combination with RBV provided considerable benefit in Chinese naïve patients with chronic hepatitis C. Treatments with IFN beta-1a alone or IFN beta-1a plus RBV are safe and well tolerated, and may represent an alternative for chronic hepatitis C patients who are unable to tolerate pegylated interferon alpha.

Potent induction therapy with interferon and ribavirin combination therapy does not achieve a higher sustained virological response rate in chronic hepatitis C with genotype 1b and high hepatitis C virus RNA level

AIMS

To compare twice-daily interferon (IFN)-beta administration and once-daily IFN-alpha-2b administration as induction therapy in ribavirin combination therapy in chronic hepatitis C with a high viral load of genotype-1b hepatitis C virus (HCV).

METHODS

Sixty-one chronic hepatitis patients with a high viral load of genotype-1b HCV were randomly divided into three groups: group A was given IFN-beta 6 MU induction therapy twice daily for 2 weeks; group B was given IFN-alpha-2b 6 MU induction therapy once daily for 2 weeks; and group C was given no induction therapy. All three groups were then given IFN-alpha-2b 6 MU 3 days/week for the rest of the 24-week study period. Ribavirin was given for the entire 24-week study period.

RESULTS

Although the cumulative HCV-RNA negative rates tended to be higher in group A than in group B, the differencewas not significant. The HCV-RNA negative rate at week 2 was significantly higher in groups A and B than in group C (P < 0.05). The sustained virological response (SVR) rate was 16% overall, 21% for groups A and B, and 5% for group C; the SVR rate of groups A plus B tended to be higher than that of group C (P = 0.093).

CONCLUSIONS

There was no difference between the effects of the two induction therapies; potent induction therapy does achieve higher early viral clearance but not a higher SVR rate.

Randomized trial of interferon beta-1a with or without ribavirin in Asian patients with chronic hepatitis C

The standard of care for chronic hepatitis C virus (HCV) infection, pegylated interferon (IFN) alpha plus ribavirin, results in a sustained virologic response (SVR) in approximately 50%-60% of patients. IFN beta is a potential alternative to IFN alpha. The aim of this study was to investigate the efficiency and durability of IFN beta and its combination with ribavirin in the naïve setting of chronic hepatitis C in Asian patients. In the initial randomized, double-blind phase, patients with chronic hepatitis C (n = 257) received 12 weeks of treatment with IFN beta-1a, 44 mug subcutaneously 3 times weekly, or a placebo. In the subsequent open-label phase, placebo nonresponders received 24 weeks of treatment with IFN beta-1a plus ribavirin, whereas patients receiving IFN beta-1a monotherapy received an additional 12 weeks of therapy. The primary outcome variable was SVR, which was defined as negative HCV RNA after weeks 24 and 48. A total of 34 of 128 patients (26.6%) receiving IFN beta-1a achieved an SVR versus 0 of 129 patients (0%) receiving the placebo (P < 0.001). In the IFN beta-1a/ribavirin group, 73 of 127 patients (57.5%) achieved an SVR [P < 0.001 versus IFN beta-1a; the adjusted odds ratio was 4.54 (95% confidence interval: 2.53, 8.13)]. In HCV genotype 1 patients, 37 of 80 patients (46.3%) treated with IFN beta-1a/ribavirin achieved an SVR versus 19 of 85 patients (22.4%) treated with IFN beta-1a (P = 0.001).

CONCLUSION

IFN beta-1a produced a clear antiviral effect in Asian patients with chronic HCV infection. The addition of ribavirin to IFN beta-1a significantly increased the proportion of patients who achieved an SVR versus IFN beta-1a monotherapy.

Is interferon-beta an alternative treatment for chronic hepatitis C

The treatment of chronic hepatitis C (CHC) is still far from optimal, particularly for those subpopulations that do not respond to the standard combination therapy with Interferon-α (IFNα) plus ribavirin. Although in some cases the use of higher doses or longer treatment periods may be effective, these approaches are generally associated with a higher incidence of adverse events, which may either lead to a reduction in patient compliance or require drug withdrawal. IFNβ could represent an interesting alternative for treating CHC patients. Controversial data about IFNβ efficacy in CHC exist, the main reason being that many results stem from pilot studies with small cohorts of patients. However, promising results have been obtained in some subgroups of patients that fail to respond to IFNα. Additionally, the good tolerability of IFNβ represents an important advantage of the drug. The rates of dropouts in controlled clinical trials, as well as the need for dose reductions or treatment discontinuation are very low. It might be worth assessing the value of IFNβ plus ribavirin in randomized studies with a larger cohort of patients, not eligible or not tolerating standard therapy, and for non-responders.

Induction therapy with twice-daily interferon-beta does not improve the therapeutic efficacy of consensus interferon monotherapy for chronic hepatitis C

We examined therapeutic superiority of induction therapy with twice-daily IFN-beta (3X2=6 million units/day) onto 6-months consensus interferon monotherapy for chronic hepatitis C. Patients were randomly assigned to monotherapy without (group I, n=16) and with induction therapy (group II, n=12). The mean age of group II was older than that of group I, and other baseline condition was not statistically significant. Sustained virological response (SVR) rates of group I and II were 81.3% (13/16) and 58.3% (7/12), respectively (p=0.365). SVR rates in patients with genotype 1b were 66.7% (4/6) and 0% (0/2, because of drop-out), and those with high viral load were 70% (7/10) and 75% (6/8) in group I and II, respectively (p=1.000). Drop-out rates during therapy were 6.3% (1/16) and 33.3% (4/12) in group I and II, respectively (p=0.176). Age less than 50 years was the only independent factor that was shown by multivariate logistic model analysis to be associated with a sustained virological response. Although randomization failed to produce and equal age distribution in the two groups in this study, our results suggest that induction therapy with twice-daily IFN-beta has no beneficial effect on the efficacy of monotherapy with consensus interferon, probably because of the higher drop-out rates and incidence of adverse reactions with induction therapy.

Safety of interferon β treatment for chronic HCV hepatitis

Hepatitis C is a major cause of liver-related morbidity and mortality worldwide. In fact, chronic hepatitis C is considered as one of the primary causes of chronic liver disease, cirrhosis and hepatocellular carcinoma, and is the most common reason for liver transplantation. The primary objectives for the treatment of HCV-related chronic hepatitis is to eradicate infection and prevent progression of the disease. The treatment has evolved from the use of α -interferon (IFNα) alone to the combination of IFNα plus ribavirin, with a significant improvement in the overall efficacy, and to the newer PEG-IFNs which have further increased the virological response, used either alone or in combination with ribavirin. Despite these positive results, in terms of efficacy, concerns are related to the safety and adverse events. Many patients must reduce the dose of PEG-IFN or ribavirin, others must stop the treatment and a variable percentage of subjects are not suitable owing to intolerance toward drugs. IFNβ represents a potential therapeutic alternative for the treatment of chronic viral hepatitis and in some countries it plays an important role in therapeutic protocols. Aim of the present paper was to review available data on the safety of IFNβ treatment in HCV-related chronic hepatitis.

The rates of treatment discontinuation and/or dose modification due to the appearance of severe side effects during IFNβ are generally low and in several clinical studies no requirements for treatment discontinuation and/or dose modifications have been reported. The most frequent side effects experienced during IFNβ treatment are flu-like syndromes, fever, fatigue and injection-site reactions. No differences in terms of side-effect frequency and severity between responders and non-responders have been reported. A more recent study, performed to compare IFNβ alone or in combination with ribavirin, confirmed the good safety profile of both treatments. Similar trends of adverse event frequency have been observed in subpopulations such as patients with genotype-1b HCV hepatitis unresponsive to IFNα treatment or with HCV-related cirrhosis and patients with acute viral hepatitis. If further studies will confirm the efficacy of combined IFNβ and ribavirin treatment, this regimen could represent a safe and alternative therapeutic option in selected patients.

Treatment of chronic hepatitis C infection with cryoglobulinemia

Mixed cryoglobulinemia is characterized by a wide spectrum of manifestations that may vary from mild symptoms (such as purpura, arthralgias, and Raynaud phenomenon) to life-threatening conditions (such as acute abdomen, hyperviscosity syndrome, and renal involvement). Hepatitis C virus infection is considered the principal trigger of the disease. Therefore, the treatment not only should be tailored to the prevailing symptom but also take into account the presence of a chronic, often smoldering infection. Symptomatic therapies are to be used in cases of minor clinical manifestations and aggressive modalities in cases of life-threatening conditions. The use of aggressive cytotoxic regimens should actually be stopped and every potentially immunosuppressive drug should be used with caution. Antiviral medications are used with growing frequency. To date, a few small trials with interferon-alpha alone or in combination with ribavirin in mixed cryoglobulinemia have been conducted. This overview deals with the current approach to the management of mixed cryoglobulinemia, focusing in particular on antiviral treatment in hepatitis C virus infection with or without mixed cryoglobulinemia.

Dynamics of hepatitis C virus monitored by real-time quantitative polymerase chain reaction during first 2 weeks of IFN-beta treatment are predictive of long-term therapeutic response

The relation between the change in hepatitis C virus (HCV) RNA levels at the start of interferon-beta (IFN-beta) treatment and the long-term therapeutic response remains poorly defined. In 20 patients with chronic hepatitis C who received IFN-beta (total dose 126-756 MU), the changes in serum HCV RNA during the first 2 weeks of therapy were monitored by real-time quantitative polymerase chain reaction (PCR). The serum HCV RNA level decreased rapidly during the first 24 h of therapy (first phase) and more slowly thereafter (second phase), with a mean exponential decay rate of 1.17 log10/day and 0.37 log10/day, respectively. Three patients had a sustained virologic response, 10 patients had a transient response, and 7 patients had no response. The differences in the rate of first-phase viral decline among the three groups were not significant (p = 0.21), but the differences in the rate of second-phase viral decline were significant (p = 0.0021). The mean decay rate between the end of the first 24 h and day 14 was 0.96 +/- 0.43 log10/day in sustained responders, 0.39 +/- 0.30 log10/day in transient responders, and 0.13 +/- 0.09 log10/day in nonresponders. We conclude that during the first 2 weeks of therapy, changes in serum HCV RNA levels as monitored by real-time quantitative PCR can be used to predict the long-term response to treatment with IFN-beta.