Hepatitis B virus quasispecies evolution after liver transplantation in patients under long‐term lamivudine prophylaxis with or without hepatitis B immune globulin

Aims To investigate an optimal long-term prophylactic strategy for prevention of hepatitis B virus (HBV) recurrence after liver transplantation, we conducted a randomized study of 29 transplant recipients receiving a short course of hepatitis B immune globulin (HBIg) + lamivudine (LAM), followed by randomization to long-term prophylaxis with LAM with or without HBIg. Methods The efficacy and safety, and impact on survival and HBV recurrence of these 2 prophylactic regimens were compared over a mean period of 10 years. In patients with viral recurrence, the HBV quasispecies in the surface/polymerase region were studied by ultra-deep pyrosequencing (UDPS). Results The 10-year survival rate was 76% and was not affected by the type of prophylaxis. Four patients had hepatitis B surface antigen (HBsAg) recurrence within the first 48 months after orthotopic liver transplantation (OLT). HBsAg-positive and -negative patients showed similar mean survival times, with no differences between the 2 regimens. Low HBV DNA levels were transiently detected in 32% of HBsAg-negative patients. UDPS showed major changes after OLT in the HBV quasispecies of patients with viral recurrence, which may be explained by a “bottleneck” effect of OLT together with prophylactic therapy. Conclusion Long-term survival after OLT in end-stage chronic hepatitis B patients was good with both prophylactic strategies. However, low, transient HBV DNA levels were detected even in the absence of HBsAg, showing the importance of continuing HBV prophylaxis.