Finite nucleos(t)ide analog therapy in HBeAg-negative chronic hepatitis B: an emerging paradigm shift.

Potent nucleos(t)ide analogs (NUC), such as entecavir and tenofovir disoproxil fumarate, are able to suppress HBV DNA to undetectable level. These agents have no direct action on cccDNA, which is a very stable template for HBV production, hence long-term or even life-long NUC therapy is required in HBeAg-negative patients to maintain HBV suppression and to achieve the ultimate goal of HBsAg loss. However, there are concerns of indefinite or life-long NUC therapy, including drug resistance, financial burden, adherence and willingness for indefinite long-term NUC therapy. Patients lost to follow-up and hence, not monitored may risk severe relapse that may deteriorate to hepatic decompensation or even hepatic failure. This Review integrated the cumulated evidence and assessed the strategy of finite NUC therapy in HBeAg-negative patients which was first tried in early 2000s. Earlier Asian findings that 2-year NUC therapy is feasible and safe have founded APASL stopping rule for patients on NUC therapy over 2-3 years since 2008. Subsequent studies have supported the strategy of finite NUC therapy, which has finally been accepted as an option by American and European liver associations since 2016. More recent studies have further shown greatly increased HBsAg loss rate (up to 5-year 39%) after stopping NUC therapy. The cumulated evidence has shown that the paradigm shift from indefinite long-term therapy to finite NUC therapy in HBeAg-negative patients is emerging. More studies are needed to fine-tuning the strategy including research for the optimal duration of consolidation therapy, timing to stop and to start re-treatment.