"Current clinical practice guidelines regard HBsAg seroclearance as the state of “functional cure”.2Previous studies showed that the predicted median time to HBsAg loss to be 36-52.2 years.4,7,8In HBV genotype D patients, a greater decline in HBsAg was observed in patients treated with more potent nucleos(t)ide analogue, such as entecavir or tenofovir, compared to telbivudine, with an estimated time to HBsAg loss of 17 years.3Although genotyping of the patients was not done, as genotype C predominates in 99% of HBV infected patients in Korea,10 the slower decline of quantitative HBsAg in our study may be representative of the decline in genotype C patients (74.1 and 73.5 years in HBeAg positive and negative patients, respectively).In this study, the difference in the quantitative HBsAg kinetics between HBeAg-positive and HBeAg-negative patients was not significant (p=0.48). On the contrary, a previous study reported a difference in the HBsAg kinetic patterns between HBeAg-positive and –negative patients.7The contradicting results of the kinetics based on the HBeAg-positivity warrants further studies. "