Methods and products related to treatment and prevention of hepatitis C virus infection

Abstract

The invention provides methods for identifying and treating subjects having hepatitis C infections. In some instances, the subjects are those that are non-responsive to non-CpG therapy. Preferably, the subjects are treated with C class CpG immunostimulatory nucleic acids having a semi-soft backbone.

Description

FIELD OF THE INVENTION [0001] The invention provides methods and products for the treatment of subjects chronically infected with hepatitis C virus. BACKGROUND OF THE INVENTION [0002] The hepatitis C virus (HCV) is a positive strand RNA virus of the Flavivirus family that infects hepatocytes of humans and some other primates. First characterized in 1989 (1), HCV has a 9.5 kb genome that encodes for three structural proteins: core and two envelope glycoproteins (E1 and E2), as well as several non-structural (NS) proteins that are involved in the viral replication and interaction with the host cell (2). [0003] HCV is a serious public health concern, causing >90% of parenteral non-A, non-B hepatitis (1). From 0.4 to 1.5% of the world's population is infected (3, 4), including about 300,000 Canadians (Health Canada). Epidemiological statistics are difficult to compile since the vast majority of acute infections are subclinical; however it is estimated that 50-80% of HCV infected indi...

AI Technical Summary

Benefits of technology

"The invention is based on the discovery that CpG immunostimulatory nucleic acids can be used to treat chronic hepatitis C virus (HCV) infections that were previously non-responsive to non-CpG therapies. Combining CpG immunostimulatory nucleic acids with interferon-alpha or other anti-viral agents can lead to a synergistic response, resulting in improved treatment outcomes for chronic HCV infections. The invention provides a method of treating a subject with an HCV infection by administering a CpG immunostimulatory nucleic acid in an amount effective to treat the infection. The CpG immunostimulatory nucleic acid may have a phosphorothioate backbone modification or a semi-soft backbone. The invention also includes a method of administering a combination of a CpG immunostimulatory nucleic acid and interferon-alpha to a subject with an HCV infection. The CpG immunostimulatory nucleic acid may be administered to a subject likely to be non-responsive to a non-CpG therapy. The invention also includes a method of identifying a subject likely to be non-responsive to a non-CpG therapy. The combination of a CpG immunostimulatory nucleic acid and interferon-alpha may be synergistic in treating chronic HCV infections."

Problems solved by technology

Epidemiological statistics are difficult to compile since the vast majority of acute infections are subclinical; however it is estimated that 50-80% of HCV infected individuals fail to clear the virus, and most of these become life-long carriers.

Although more expensive and associated with more side effects, combination therapy consistently yields higher rates of sustained response than monotherapy.

However, results depend strongly on the genotype of virus, with better results being obtained for genotypes 2 and 3 (about 90% with 1 year of treatment with pegylated IFN-α and Ribavirin), but much poorer results (about 40% sustained response) for genotype 1 HCV.

There is currently no vaccine against HCV, or highly effective therapy for chronic infection.

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