Successful direct-acting antiviral treatment of three patients with genotype 2/1 recombinant hepatitis C virus

  • Masako Okada
  • Hoang Hai
  • Akihiro Tamori
  • Sawako Uchida-Kobayashi
  • Masaru Enomoto
  • Hiromitsu Kumada
  • Norifumi Kawada
Case Report


There have been a few reports on the treatment of patients infected with recombinant hepatitis C virus (HCV) genotype 2/1 strains with direct-acting antivirals (DAAs). We experienced three patients, with genotype 2/1 recombinant HCV, treated with DAAs successfully. The first, a 39-year-old man, was infected with recombinant HCV genotype 2a/1b, a rare variant. The sequence of the relapsed virus showed chimeric HCV 2a/1b with the recombinant breakpoint found at nucleotide +49 from the start of the NS3 region. Sofosbuvir plus ribavirin, a regimen recommended for HCV genotype 2, did not lead to a sustained viral response (SVR). Retreatment with grazoprevir plus elbasvir resulted in an SVR. The second case, a 70-year-old woman, was infected with recombinant HCV genotype 2b/1b. DAA therapy with sofosbuvir plus ledipasvir resulted in an SVR. The third case, a 48-year-old woman, was also infected with recombinant HCV genotype 2b/1b. DAA therapy with daclatasvir plus asunaprevir resulted in an SVR. The baseline sequences of the viruses from both the second and third cases showed chimeric HCV 2b/1b with the recombinant breakpoint found at nucleotide +10 from the NS3 start. We report three cases with 2/1 chimeras and discuss the prevalence and response to therapy.


Chimeric HCV Direct-acting antivirals HCV genotype 2/1 



This research was supported in part by an Osaka City University Strategic Research Grant in 2017 for basic research (A.T.).

Compliance with ethical standards

Conflict of interest

Dr. H Kumada has received lecture fees from AbbVie Inc., Bristol-Myers Squibb, Gilead Sciences, and MSD K.K. Dr. N Kawada has received lecture fees from Gilead Sciences, and MSD K.K. Dr. A Tamori has received a lecture fee from Gilead Sciences. Other authors declare that they have no conflict of interest.

Human/animal rights

All procedures followed have been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments.

Informed consent

Informed consent was obtained from all patients for being included in the study.


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Copyright information

© Japanese Society of Gastroenterology 2018

Authors and Affiliations

  1. 1.Department of HepatologyOsaka City University Graduate School of MedicineOsakaJapan
  2. 2.Department of HepatologyToranomon HospitalTokyoJapan

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