[Mutations within the interferon sensitivity determining region in Korean patients infected with hepatitis C virus genotype 1b].
OBJECTIVE
The treatment response to interferon could differ with mutations in the interferon-sensitivity-determining region (ISDR) in patients infected with hepatitis C virus (HCV) genotype-1b (HCV-Ib). We examined the pattern of ISDR mutations and analyzed whether the number of amino acid substitutions influences the treatment response to peginterferon plus ribavirin in chronic hepatitis or cirrhotic patients infected with HCV-Ib.


METHODS
The study population comprised 52 patients who visited Seoul Asan Medical Center and Seoul National University Bundang Hospital from January 2006 to December 2008 and who received peginterferon alpha-2a (n=37) or -2b (n=15) plus ribavirin, and whose serum was stored. We analyzed the early virologic response, end-of-treatment response, and sustained virologic response (SVR), and examined the ISDR using direct sequencing.


RESULTS
The proportions of patients with ISDR mutation types of wild (0 mutations), intermediate (1-3 mutations), and mutant (> or =4 mutations) were 50.0%, 42.3%, and 7.7%, respectively, and the corresponding SVR rates were 63%, 50%, and 67% (p>0.05). The SVR rates were 59.4% and 50.0% in patients with <2 and > or =2 mutations, respectively (p>0.05). On univariate analysis, age was the only predictive factor for SVR (p=0.016). The pretreatment HCV RNA titer tended to be lower in those with SVR, but without statistical significance (p=0.069).


CONCLUSIONS
The frequency of ISDR mutations was low in our cohort of Korean patients infected with HCV-Ib. Therefore, ISDR mutations might not contribute to the response to treatment with peginterferon plus ribavirin.
Jin
Young-Joo
YJ
Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Park
Yoon Kyung
YK
Yun
Gui Jun
GJ
Lee
Han Chu
HC
Jeong
Sook-Hyang
SH
Kim
Gang Mo
GM
Lim
Young-Suk
YS
Chung
Young-Hwa
YH
Lee
Yung Sang
YS
Suh
Dong Jin
DJ
D000328:Adult; D000368:Aged; D000595:Amino Acid Sequence; D000998:Antiviral Agents / Q000627:therapeutic use*; D024882:Drug Resistance, Viral / Q000235:genetics; D004359:Drug Therapy, Combination; D005260:Female; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics*; D019698:Hepatitis C, Chronic / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D000077190:Interferon alpha-2; D016898:Interferon-alpha / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009154:Mutation; D011092:Polyethylene Glycols / Q000627:therapeutic use*; D011994:Recombinant Proteins; D056910:Republic of Korea; D012254:Ribavirin / Q000627:therapeutic use
D000998:Antiviral Agents; D000077190:Interferon alpha-2; D016898:Interferon-alpha; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; D012254:Ribavirin; C417083:peginterferon alfa-2b; C100416:peginterferon alfa-2a