To determine the clinical characteristics of hepatitis B virus (HBV) reactivation in patients undergoing
interferon-free antihepatitis C virus (HCV)
therapy, we examined HBV
DNA in 25 HBV co-infected patients and 765 patients with resolved HBV
infection during and
after treatment with direct-acting
antiviral agents (DAAs). Among those with HCV genotype 1,
asunaprevir plus
daclatasvir was administered to 160 patients,
sofosbuvir (SOF) plus
ledipasvir to 438 patients and
paritaprevir plus
ombitasvir and
ritonavir to 25 patients. In total, 167 patients with genotype 2 were treated with SOF plus
ribavirin. Three patients with an HBV
DNA level ≥2000 IU/mL were treated with
entecavir before anti-HCV
therapy, without reactivation of HBV. In 3 of 22 (12%) HBV
surface antigen (
HBsAg)-positive patients with an HBV
DNA level <2000 IU/mL, the viral load increased during treatment. However,
hepatitis flare did not occur in these patients. There was no significant difference in clinical history between patients with and without HBV reactivation. Among 765 patients with resolved HBV
infection, HBV reactivation occurred in 1 (0.1%) patient after initial resolution, whose HBV
DNA level spontaneously decreased after DAA
therapy. We compared anti-HBs titres at baseline with those at post-DAA
therapy in 123 patients without
HBsAg. There was no significant difference in anti-HBs levels between the two points (P = .79). In conclusion, HBV reactivation was rare in
HBsAg-negative patients treated with DAA
therapy. Additionally,
hepatitis did not occur in HBV-reactivated patients with a baseline HBV
DNA level <2000 IU/mL before DAA
therapy.