HBV and HCV therapy

Modeling the dynamics of hepatitis B infection, immunity, and drug therapy

Hepatitis B virus infection is the cause of liver diseases such as cirrhosis and liver cancer. Understanding the host-virus mechanisms that mediate virus pathogenesis can help design better preventive measures for disease control. Mathematical models have been used alongside experimental data to provide insight into the role of immune responses during the acute and chronic hepatitis B infections as well as virus dynamics following administration of combined drug therapy. In this paper, we review several modeling studies on virus-host interactions during acute infection, the virus-host characteristics responsible for transition to chronic disease, and the efficacy and optimal control measures of drug therapy. We conclude by presenting our opinion on the future directions of the field.

Understanding the Complex Patterns Observed during Hepatitis B Virus Therapy

Data from human clinical trials have shown that the hepatitis B virus (HBV) follows complex profiles, such as bi-phasic, tri-phasic, stepwise decay and rebound. We utilized a deterministic model of HBV kinetics following antiviral therapy to uncover the mechanistic interactions behind HBV dynamics. Analytical investigation of the model was used to separate the parameter space describing virus decay and rebound. Monte Carlo sampling of the parameter space was used to determine the virological, pharmacological and immunological factors that separate the bi-phasic and tri-phasic virus profiles. We found that the level of liver infection at the start of therapy best separates the decay patterns. Moreover, drug efficacy, ratio between division of uninfected and infected cells, and the strength of cytotoxic immune response are important in assessing the amount of liver damage experienced over time and in quantifying the duration of therapy leading to virus resolution in each of the observed profiles.

Hepatitis B virus therapy: What’s the future holding for us?

Hepatitis B is one of the leading causes of liver cancer worldwide and unfortunately the number of people affected with hepatitis B virus (HBV) infection is still on the rise. Although the HBV has been known to cause fatal illness since decades but the population effected by this lethal virus have still only a few options for its management. The major treatment strategies include interferons and nucleos(t)ide analogues. These agents have so far produced unsatisfactory results in terms of complete virus eradication. Interferons cannot be used for long term therapy because of their potential side effects. Prolong treatment with nucleos(t)ide analogues has also been reported to cause serious side effects besides the increasing resistance by the virus. The need for new innovative solutions for treatment of HBV has been realized by global research institutes and pharmaceutical industry. Present review focuses in detail on the new ideas that are being transformed into therapeutic tools for use as future therapies in HBV infection. Modern drug designing and screening methods have made the drug discovery process shorter and more reliable. HBV therapeutics will take a new turn in coming years owing to these intelligent drug designing and screening methods. Future therapy of HBV is aiming to include the use of vaccines (both prophylactic and therapeutic), immunomodulators such as antibodies, non-nucleoside antivirals such as RNAi and inhibitors of viral life cycle.

Adjuvant interferon therapy after surgical treatment for hepatitis B/C virus-related hepatocellular carcinoma: A meta-analysis

AIM

This meta-analysis aimed to determine whether interferon (IFN) therapy could improve clinical effects of patients with chronic hepatitis B virus (HBV)or hepatitis C virus (HCV) infection-related primary hepatocellular carcinoma (HCC) after surgery.

METHODS

An electronic search from January 1998 to December 2012 was conducted to identify comparative studies evaluating IFN therapy on recurrence and survival after surgical treatment of HCC.

RESULTS

The estimated odds ratios (OR) for the 1-, 2-, 3- and 5-year overall survival rates of HBV-related HCC were 3.37 (95% confidence interval [CI], 1.18-6.27), 2.36 (95% CI, 1.45-3.83), 1.81 (95% CI, 1.21-2.72) and 1.93 (95% CI, 1.35-2.75), respectively; and the OR for the 1-, 2-, 3- and 5-year recurrence rates were 0.63 (95% CI, 0.44-0.91), 0.84 (95% CI, 0.60-1.18), 0.88 (95% CI, 0.63-1.22) and 0.78 (95% CI, 0.56-1.07), respectively. The overall survival rates of HCV-related HCC were significantly higher in IFN groups than in control groups at 1, 2, 3 and 5 years (OR, 2.10; 95% CI, 0.96-4.55; OR, 1.71; 95% CI, 1.01-2.89; OR, 1.76; 95% CI, 1.09-2.83; and OR, 3.03; 95% CI, 1.97-4.65, respectively); and the recurrence rates of IFN groups were lower than control groups at 1, 2, 3 and 5 years (OR, 0.60; 95% CI, 0.38-0.92; OR, 0.57; 95% CI, 0.41-0.81; OR, 0.58; 95% CI, 0.41-0.80; and OR, 0.52; 95% CI, 0.36-0.75, respectively).

CONCLUSION

In conclusion, IFN therapy in this meta-analysis shows a significant clinical effect in postoperative patients of HCC, particularly in HCV-related HCC.