Objective To evaluate the efficacy and drug resistance profiles of nucleosides (NA) retreatment in NA experienced chronic hepatitis B (CHB) patients. Methods Totally 104 NA experienced CHB subjects were enrolled in this study.All these subjects had received at least 3 months NA monotherapy and stopped the treatment,and then received NA retreatment for at least one year.The subjects were divided into three groups according to the following criteria:reached the therapy endpoint of China guideline when they stopped NA-naive treatment (group A,n =39); did not reach the therapy endpoint when they stopped NA-naive treatment but hepatitis B virus (HBV) DNA＜1.0× 103 copy/mL (group B,n=33); and with HBV DNA＞1.0× 103 copy/mL (group C,n=32).The efficacy and drug resistance profiles of retreatment were compared among three groups. The effects of baseline alanine aminotransferase (ALT) levels,HBV DNA levels and HBeAg titers on the retreatment efficacies were analyzed. The mutations of HBV P gene were detected by nested polymerase chain reaction (PCR) and direct sequencing.The data were analyzd by Wilcoxon test and x2 test.Results The time to ALT normalization in patients with baseline ALT＜ 1.3 × upper limit normal (ULN) was shorter than that in patients with ALT≥1.3×ULN (2 months vs 4 months; Z=2.281,P=0.023).The time to virological response in patients with baseline HBV DNA＜5 lg copy/mL was shorter than that in patients with HBV DNA≥5 lg copy/mL (1 month vs 2 months; Z=2.054,P =0.040). The time to virological response and ALT normalization in baseline HBeAg negative were both shorter than those in patients with baseline HBeAg positive patents ( 1 month vs 3 months and 2 months vs 4.5 months,respectively; Z=2.580 and 2.304,respectively; both P＜0.05). The subjects in group A achieved virological response and HBeAg seroconversion after retreatment earlier compared to previous NA-naive therapy ([1.61 ± 1.76] months vs [3.48±4.066]months and [3.38 ± 3.34] months vs [9.92-11.22] months,respectively; Z=-2.854 and-1.094,respectively; both P＜0.05).The cumulative HBeAg seroconversion rate in group A was higher compared to those in group B and group C (80.0％ vs 36.8％ and 37.5％,respectively; x2 =4.368 and 5.100,respectively; both P＜0.05).Thirteen patients developed clinical resistance and four of them developed genotypic resistance proved by PCR direct sequencing.Among the patients retreated with the same regimen as previous in the C group,the cumulative resistance rate was highest compared to group A and B (44％ vs 9％ and 0,respectively; x2 =5.019 and 6.588,respectively;both P＜0.05).No resistance was detected in the 14 patients retreated with combined NA treatment without cross resistance.Conclusions For NA experienced CHB patients who fulfill the indication of antiviral therapy,the retreatment should be started as earlier as possible. Retreatment with NA combination without cross resistance can prevent (reduce) the risk of developing drug resistance.

Objective To explore the influence factors on hepatitis B virus (HBV) relapse after nucleos(t)ide analogues (NA) withdrawal in the chronic hepatitis B (CHB) patients who met NA cessation criteria. Methods Eighty-one consecutive CHB patients were treated with NA, 38 with lamivudine (LAM), 25 with adefovir dipivoxil (ADV), 12 with entecavir (ETV), 6 with LAM +ADV. Among recruited patients, 40 were hepatitis B virus e antigen (HBeAg) positive, 41 were HBeAg negative, 67 of them were initial treatment, 14 were retreatment due to resistance to NA at baseline. The treatment was discontinued after meeting China therapeutic end-point criteria. HBV DNA, HBV serological markers, alanine aminotransferase (ALT) were measured respectively at baseline, every month before virological response, every 3 months after virological response, every month within first 6 months and every 2 months over 6 months after drugs withdrawal. Twelve probable influence factors on relapse which were sex, age, HBV family history, baseline HBV DNA,baseline HBeAg status, baseline ALT, virological response time, total duration of treatment, duration of additional treatment, the level of hepatitis B virus surface antigen (HBsAg) at cessation therapy,initial treatment or retreatment, drug category were analyzed with univariate, multivariate Cox regression modle and stratified analysis. The cumulative relapse was calculated by the Kaplan-Meier method. Results A total of 36 patients (44. 4%) relapsed within 1 year. Initial treatment or retreatment, HBV family history, virological response time, the level of HBsAg at cessation therapy were independent risk factors. The relapse rate of retreatment was higher than that of initial treatment (78.6% vs 37. 3% , χ2 = 7. 983, P = 0. 005) , those of patients with HBV family history higher than without family history (64. 5% vs 15.0%, χ2 =12. 096,P = 0.002), those of patients obtained virological response within 3 months lower than after 3 months(34. 0% vs 64. 3% , χ2 =6. 823,P=0. 009) , those of patients with HBsAg≤150 μg/L at cessation therapy lower than >150 μg/L(27. 6% vs 53. 8%, χ2=5. 199,P=0. 023). Conclusions Retreatment, HBV family history, later virological response and higher HBsAg level at cessation therapy are risk factors of relapse after NA withdrawal. Such patients should be treated with prolonged duration after meeting end-point criteria to strengthen the efficacy.