HBeAg-negative chronic hepatitis B: why do I treat my patients with pegylated interferon-alfa?

HBeAg-negative chronic hepatitis B (CHB) is the most frequent and aggressive type of CHB. The current therapeutic options for CHB include pegylated-interferon-alfa (PEG-IFNα) and nucleos(t)ide analogues (NAs). NAs are well-tolerated and safe agents that effectively inhibit viral replication, but they should be given as long-term, probably lifelong therapy, in particular in HBeAg-negative CHB. Thus, the finite, usually 48-week, duration is the main advantage of PEG-IFNα, providing sustained virological responses (SVR) off-therapy in approximately one-fourth of patients with HBeAg-negative CHB and often leading to HBsAg loss. However, the limited efficacy is the main factor restricting the use of PEG-IFNα in CHB and therefore identifying the predictors of response is of great clinical importance. No reliable baseline predictors of response to PEG-IFNα have been identified to date, but certain studies have identified satisfactory predictors of post-PEG-IFNα response using on-treatment serological markers, mostly HBsAg levels. In particular, in HBeAg-negative CHB patients mostly with genotype D a lack of decline in HBsAg levels and a lack of decrease in HBV DNA levels ≥2 log10 copies/ml at week-12 has a nearly 100% negative predictive value for SVR off-treatment and is now recommended as a stopping rule for early discontinuation of ineffective PEG-IFNα. Prolonging PEG-IFNα therapy to 96 weeks seems to provide higher SVR rates but the application and efficacy of this approach requires further study. The combination of PEG-IFNα with NAs, mostly lamivudine, has not resulted in any therapeutic benefit so far, but newer combined approaches with PEG-IFNα and NA(s) are currently under study.