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SeqHepB program (Evivar Medical) is a unique viral genomics sequence analysis
program that is linked to a HBV genomic database. It is offered as a web-based deci-
sion support tool to assist physicians to optimize and individualize the treatment
schedule of patients with chronic hepatitis B. The system can be used to identify
HBV mutations present in the patient and to determine resistance levels to the vari-
ous available medications.
A HBV Sequencing test (Abbott Molecular) has received CE Mark for identifying
genomic sequences of HBV to guide or monitor therapy, and predict or discover drug
resistance. It is not intended for screening blood, plasma, or tissue donors for HBV
or as a diagnostic test to confi rm HBV infection. ViroSeq® HBV Assay (Celera) is
in development for detection of resistance to antiviral treatment in hepatitis B.
Personalized Treatment of Hepatitis C
Hepatitis C is the most common blood-borne viral infection in the US and it is one
of the main causes of chronic liver disease. It is estimated that at least 4 million
persons in the US and 170 million persons world-wide are infected with HCV. The
complications of chronic hepatitis C, including cirrhosis and hepatocellular carci-
noma, are expected to increase dramatically world-wide over the next 10–20 years.
Immunomodulatory/anti-viral therapy, employing IFN-α, both alone and in combi-
nation with ribavirin, affords the only effective treatment for hepatitis C. Accurate
early prediction of response to IFN therapy may decrease or eliminate unnecessary
or ineffective treatment, permit greater fl exibility in tailoring therapy on an indi-
vidual basis, and enhance the cost-effectiveness of treatment. Liver biopsy provides
valuable information about the baseline severity and subsequent progression of
hepatitis C. Severe fi brosis or cirrhosis on the pre-treatment liver biopsy is associ-
ated with decreased response rates.
Genotype and Response to Treatment for Hepatitis C
The current standard of care for HCV is PegIFN-α in combination with ribavirin.
The treatment regimen lasts for 6–12 m and can lead to a permanent cure in some
patients, depending upon the genotype of HCV infection and other factors not well
understood. Response rates to currently approved therapies also vary by genotype,
with genotype 2 and 3 patients enjoying a 76 % response rate to the current standard
of care while patients with genotype 1a and 1b have only a 46 % response to the
current standard of care. Unfortunately HCV genotype 1 accounts for 60 % of
global infections and is the dominant strain in the US, Japan and Western Europe.
In a randomized study of patients infected with HCV genotype 1, the rates of sus-
tained virologic response and tolerability did not differ signifi cantly between the 2
available peginterferon-ribavirin regimens or between the 2 doses of PEG-IFN α-2b
(McHutchison et al. 2009 ).
11 Personalized Management of Infectious Diseases