Long-term prognosis by lamivudine monotherapy for severe acute exacerbation in chronic hepatitis B infection: emergence of YMDD motif mutant and risk of breakthrough hepatitis -- an open-cohort study

Chronic Hepatitis B with Spontaneous Severe Acute Exacerbation

Chronic hepatitis B virus (HBV) infection is a major global health problem with an estimated 400 million HBV carriers worldwide. In the natural history of chronic hepatitis B (CHB), spontaneous acute exacerbation (AE) is not uncommon, with a cumulative incidence of 10%–30% every year. While exacerbations can be mild, some patients may develop hepatic decompensation and even die. The underlying pathogenesis is possibly related to the activation of cytotoxic T lymphocyte-mediated immune response against HBV. An upsurge of serum HBV DNA usually precedes the rise of alanine aminotransferase (ALT) and bilirubin. Whether antiviral treatment can benefit CHB with severe AE remains controversial, but early nucleos(t)ide analogues treatment seemed to be associated with an improved outcome. There has been no randomized study that compared the effects of different nucleos(t)ide analogues (NA) in the setting of CHB with severe AE. However, potent NAs with good resistance profiles are recommended. In this review, we summarized current knowledge regarding the natural history, pathogenetic mechanisms, and therapeutic options of CHB with severe AE.

Treatment of pegylated interferon-α2a in chronic hepatitis B patients demonstrating a spontaneous decline in HBV DNA after acute exacerbation

BACKGROUND

Acute exacerbation (AE) in chronic hepatitis B (CHB) is usually followed by a spontaneous decline in HBV DNA levels. The subsequent treatment is controversial. In this study, we evaluated the efficacy and safety of pegylated interferon-α2a (PEG-IFN-α2a) for such CHB patients.

METHODS

A total of 74 hepatitis B e antigen (HBeAg)-positive patients with a spontaneous HBV DNA decline (by >2 log10 IU•ml(-1), compared with baseline levels before antiviral treatment) after AE (alanine aminotransferase [ALT]: 10-30-fold the upper limit of normal [ULN], total bilirubin [TBIL]: 2-20 mg•dl(-1), prothrombin time activity >60%) were included. In total, 22 patients (group A) received PEG-IFN-α2a treatment (180 µg•kg(-1)•week(-1), when ALT was <10 ULN and TBIL<2 mg•dl(-1)) for 48 weeks, with 48 weeks of treatment-free follow-up. Twenty-one patients (group B) selected continual entecavir therapy. Thirty-one patients (group C, control group) received routine liver-protective drugs.

RESULTS

At week 96, virological response rates were 90.5%, 100% and 48%, and ALT normalization rates were 81%, 95% and 40% for groups A, B and C, respectively. HBeAg seroconversion rates were 71.4%, 45% and 32% in groups A, B and C, respectively. A high hepatitis B surface antigen (HBsAg) loss rate was observed in PEG-IFN-α2a-treated patients, while no entecavir-treated patients achieved HBsAg loss. Group A patients suffered from typical PEG-IFN therapy-related adverse events. No severe adverse event was observed in any groups.

CONCLUSIONS

PEG-IFN-α2a is effective and safe for treating CHB patients demonstrating a spontaneous decline in HBV DNA after AE, and yields an increased likelihood of HBsAg loss.

Clearance of hepatitis B surface antigen during long-term nucleot(s)ide analog treatment in chronic hepatitis B: results from a nine-year longitudinal study

BACKGROUND

Clearance of hepatitis B surface antigen (HBsAg) is considered the ultimate goal in chronic hepatitis B treatment. One treatment option is long-term nucleot(s)ide analog (NA) therapy. We followed a group of long-term NA therapy patients to evaluate the efficacy of this treatment in promoting clearance and longitudinal declines of HBsAg.

METHOD

The study included 791 NA therapy patients who received lamivudine as their first drug. At the baseline, 442 patients were hepatitis B e antigen (HBeAg)+ and 349 were HBeAg-. All analyses were performed after separating the HBeAg+ and HBeAg- cohorts. Cox proportional hazards models were used to determine which factors were associated with HBsAg clearance.

RESULTS

HBsAg clearance was observed in 18 (4.1 %) of the HBeAg+ patients and 20 (5.7 %) of the HBeAg- patients at baseline, giving seroclearance rates of 6.4 and 6.9 %, respectively, over the nine-year study period. HBsAg clearance was influenced by several independent factors that varied according to HBeAg cohort. For HBeAg+ patients, these included previous interferon therapy, infection with hepatitis B virus (HBV) genotype A, a ≥0.5 log IU/mL decline in HBsAg level within six months, and clearance of HBeAg at six months. For HBeAg- patients, these included infection with HBV genotype A, decline in HBsAg at six months, and a baseline HBsAg level of <730 IU/mL.

CONCLUSION

This study suggests that both direct antiviral potential and host immune response are needed to achieve HBsAg clearance by NA therapy. Viral genotype strongly influenced HBsAg clearance during NA therapy.

The efficacy and safety of Nucleos(t)ide analogues in patients with spontaneous acute exacerbation of chronic hepatitis B: a systematic review and meta-analysis

BACKGROUND

Spontaneous acute exacerbation (AE) of chronic hepatitis B (CHB) is often detrimental but sometimes leads to sustained immune control and disease remission. The efficacy and safety of nucleos(t)ide analogues (NAs) in patients with spontaneous AE of CHB remains unclear.

METHODS

We performed a systematic review and meta-analysis of NAs in patients with spontaneous AE of CHB. We calculated pooled effects of NAs in these patients of each study and conducted quantitative meta-analysis, displaying results using Forest plots.

RESULTS

15 studies were included and substantial heterogeneity was noted in the inclusion/exclusion criteria and controls. Pooled data showed no benefit of lamivudine (LAM) vs. untreated controls for transplant-free survival in patients with spontaneous AE of CHB (OR = 0.98 (95% CI, 0.50-1.92; P = 0.956)), hepatic decompensation (OR = 0.94 (95% CI, 0.47-1.88; P = 0.862)) and liver failure owing to AE (OR = 2.30 (95% CI, 0.35-15.37; P = 0.387)) at 3 months. Entecavir achieved even higher short-term mortality than LAM. NAs led to rates of ALT normalization, undetectable HBV DNA, HBeAg loss, HBeAg seroconversion and drug resistance at 1 year in 88%, 61%, 46%, 35% and 5%. Pooled data also showed benefit favoring LAM vs. untreated controls for ALT normalization (OR = 1.98 (95% CI, 1.03-3.80; P = 0.039)) and undetectable HBV DNA (OR = 38.50 (95% CI, 7.68-192.99; P<0.001)) at 3 months. All NAs were relatively safe and well tolerated.

CONCLUSION

NAs had no obvious impact on short-term survival in patients with AE of CHB, despite of possible better antiviral responses. We suggest additional studies to evaluate the efficacy of other NAs and early introduction of immunosuppressant in combination with NAs. We highlight developing prognostic models to identify predictors of mortality and disease progression for AE of CHB.

Predictors for early HBeAg loss during lamivudine therapy in HBeAg-positive chronic hepatitis B patients with acute exacerbation

PURPOSE

To examine the rate of early HBeAg loss and predictors of HBeAg loss in HBeAg-positive chronic hepatitis B (CHB) patients with acute exacerbation (AE) treated with lamivudine.

METHODS

A total of 146 patients diagnosed with CHB and AEs were included in this retrospective study. Patients were divided into two groups: decompensated and compensated.

RESULTS

The mean treatment duration for the decompensated and compensated groups was 18.1 and 19.9 months, respectively. Decompensated patients were significantly older and had a higher prevalence of cirrhosis and genotype B infection than compensated patients. Compared to compensated patients, decompensated patients achieved a higher rate of HBeAg loss (25.8 vs. 14.3%; P = 0.0805) at 3 months of therapy, a higher rate of serum HBV DNA negativity (53.2 vs. 29.8%; P = 0.0042), and a lower rate of rtM204V/I mutation (3.2 vs. 16.7%; P = 0.0139) after 12 months of lamivudine therapy. The rates of HBeAg loss after 6 and 12 months of lamivudine therapy were similar between the two groups. Logistic regression analysis revealed that female gender and baseline ALT level ≥1,000 IU/L, but not decompensations, were significant predictors of HBeAg loss at 3 months; however, only female gender was a significant predictor of HBeAg loss after 6 and 12 months of lamivudine therapy. The early HBeAg losers showed a significantly higher sustained remission rate off lamivudine therapy.

CONCLUSIONS

Female gender and baseline serum ALT level ≥1,000 IU/L were independent predictors of early HBeAg loss during lamivudine therapy in HBeAg-positive CHB patients with AE.

ELECTRONIC SUPPLEMENTARY MATERIAL

The online version of this article (doi:10.1007/s12072-010-9227-x) contains supplementary material, which is available to authorized users.

Quantification of lamivudine-resistant hepatitis B virus mutants by type-specific TaqMan minor groove binder probe assay in patients with chronic hepatitis B

BACKGROUND

Lamivudine (LAM)-resistant hepatitis B virus (HBV) with mutations in the polymerase region frequently appears after long-term use of LAM. Several methods allowing detection of mutant strains (YIDD, YVDD) have been reported, but they have no quantitative characteristics. In this study, we explored a unique approach for quantification of each mutant strain.

METHODS

A method for detection and quantification of wild and mutant strains was developed using realtime polymerase chain reaction and type-specific minor groove binder (MGB) probes, and tested in patients with chronic hepatitis B before and after additive treatment with adefovir dipivoxil (ADV).

RESULTS

A good correlation was confirmed in HBV DNA quantity obtained between the YMDD-specific MBG probe assay and Amplicor HBV Monitor assay results (P < 0.001), linear between 3 and 9 log copies/mL serum. Of 109 samples from patients with chronic hepatitis B tested by both these assays and conventional direct sequencing, 90 (88.2%) showed identical results. The assays successfully detected and quantified a single type of mutant in three of four patients with additive ADV treatment, and also two coexisting mutant types (YIDD and YVDD) in the remaining patient.

CONCLUSIONS

Our specific and sensitive method for detection and quantification of HBV DNA with the wild-type YMDD motif and its two mutant forms (YIDD and YVDD) appears to be clinically useful, especially in patients with multiple mutant HBV infections.

Prolonged persistence of lamivudine-resistant mutant and emergence of new lamivudine-resistant mutants two years after lamivudine withdrawal in HBsAg-positive chronic hepatitis patient: a case report

Lamivudine can select resistant hepatitis B virus (HBV) tyrosine-methionine-aspartate-aspartate aminoacid motif (YMDD) mutants, which usually disappear in few months after lamivudine withdrawal. We report an unusual case of a male adult patient who showed a prolonged persistence of the M204I mutation up to 24 months after lamivudine withdrawal followed by the emergence of new distinct YMDD mutants (namely M204V, V207L). Only 42 months after lamivudine withdrawal wild-type YMDD motif became dominant over the YMDD mutants. To our knowledge, a so prolonged persistence of a YMDD mutant and also the emergence of new YMDD mutants many months after drug withdrawal are unusual.

Characteristics of lamivudine-resistant hepatitis B virus (HBV) strains with and without breakthrough hepatitis in patients with chronic hepatitis B evaluated by serial HBV full-genome sequences

Lamivudine therapy often causes breakthrough of hepatitis B virus (HBV) DNA and breakthrough hepatitis. The aim of this study was to determine the viral factors that relate to HBV-DNA breakthrough with and without breakthrough hepatitis. Among 82 patients with chronic hepatitis B (CHB) who received lamivudine at a dose of 100 mg daily for more than 24 months, 23 patients had HBV-DNA breakthrough induced by a lamivudine-resistant mutant. Of these 23 patients, 16 had breakthrough hepatitis and 7 had only HBV-DNA breakthrough. Serial HBV-DNA full-genome sequences during therapy were examined in 10 (7 had breakthrough hepatitis and 3 did not) of these 23 patients by direct sequencing. Mutations in the S region were examined by cloning in representative patients. There were no significant differences in the baseline clinical backgrounds and virus marker between patients with and without breakthrough hepatitis. The HBV amino acid substitutions at breakthrough hepatitis were identical to those at HBV-DNA breakthrough. Cloning analysis revealed that monoclonal mutational strain appeared at breakthrough and no such mutations existed at baseline. Regarding HBV amino acid substitutions in the polymerase region, S region, X region, and precore-core region with breakthrough compared to baseline, there was no significant differences of the numbers of amino acid substitution between breakthrough hepatitis and non-breakthrough hepatitis. There were no common amino acid changes in patients with breakthrough hepatitis. Although monoclonal lamivudine-resistant strain emerged at HBV-DNA breakthrough in patients with CHB, there were no common amino acid changes, suggesting viral factor may have insignificant role in breakthrough hepatitis.

Interferon and lamivudine monotherapy on chronic hepatitis B in Japan

AIM

We show data of interferon (IFN) and lamivudine monotherapy on chronic hepatitis B in Japan.

METHODS

Data collected from sixty-six chronic hepatitis B (CHB) Japanese patients who were treated with IFN for 6 months were analyzed. The efficacy of long-term IFN therapy in 52 patients with e-antigen positive CHB, and data from 290 chronically HBV-infected patients who were treated with lamivudine for more than 3 years, were analyzed.

RESULTS

Six-month IFN therapy: among 45 patients with HBeAg at commencement of IFN therapy, nine (20%) were responders. Young patients especially those with high serum alanine aminotransferase (ALT) levels were much more likely to respond to IFN therapy. Twelve-month IFN therapy: theresponse rate was 31% among 52 patients with HBeAg. Long-term lamivudine therapy: YMDD motif mutation was detected in 167 of 290 patients (58%) during lamivudine treatment. Breakthrough hepatitis from lamivudine resistant virus was detected in 93 of 290 patients (32%). Finally, 813 patients were treated by lamivudine between September 1995 and February 2006. Fifteen patients lost HBsAg during and after lamivudine therapy.

CONCLUSION

Long-term interferon therapy has a better response than short-term interferon therapy. Some patients lost HBsAg during and after lamivudine therapy.

Changes in viral loads of lamivudine-resistant mutants during entecavir therapy

AIM

Entecavir therapy is effective against lamivudine-resistant virus in patients with hepatitis B virus infection. We investigated viral load changes of YMDD mutant virus (rtM204I [YIDD sequence], rtM204V [YVDD]) in serial serum samples during entecavir treatment for lamivudine-resistant virus and determined changes in viral precore and core promoter mutants.

METHODS

Nineteen patients were treated in randomized, double-blind phase II clinical trials of entecavir at 0.5 or 1.0 mg for breakthrough hepatitis due to lamivudine-resistant virus. Viral changes in YMDD mutants (rtM204I, rtM204V), amino acid changes in the polymerase reverse transcriptase region and precore/core promoter mutations at 52 weeks were determined in 18 patients.

RESULTS

Changes in viral loads of rtM204I and rtM204V were similar. No differences in load changes were seen betweenthe 0.5 and 1.0 mg groups. However, load changes for rtM204I alone were greater than those for the rtM204I + rtM204V mixed-type (P = 0.042, at both 40 and 52 weeks). Load changes in rtM204I and rtM204V with G1896A tended to be greater than those without. Moreover, G1896A was replaced by wild-type virus in two patients at 52 weeks.

CONCLUSION

RtM204I only or the existence of precore mutation was more sensitive to entecavir therapy against lamivudine-resistant virus.

Efficacy of lamivudine therapy in elderly patients with chronic hepatitis B infection

BACKGROUND

The aim of this study was to evaluate the efficacy of lamivudine therapy in elderly patients with chronic HBV infection.

METHODS

Patients aged >or=60 years (n = 40) received lamivudine monotherapy between February 1995 and September 2005 at Toranomon Hospital. We compared the efficacy of lamivudine therapy in these patients and in 639 patients aged <60 years, including 80 patients aged <60 years matched for sex, hepatitis B e antigen (HBeAg) status, and hepatitis B virus (HBV) DNA level.

RESULTS

The rates of normalization of alanine aminotransferase (ALT) level in 40 patients aged >or=60 years and 639 patients aged <60 years were 85% versus 76%, and 86% versus 73% at 1 and 3 years, respectively. The respective rates of loss of HBV-DNA were 74% versus 74%, and 76% versus 68% at 1 and 3 years. The respective cumulative emergence rates of the YMDD mutant were 16% and 17% at 1 year, and 46% and 49% at 3 years. In 80 patients <60 years old matched for sex, HBeAg status, and HBV-DNA level, the rates of normalization of the ALT level and loss of HBV-DNA were similar to those in the 639 patients aged <60 years. The emergence rate of YMDD mutants in patients aged >or=60 years were similar to those in matched patients aged <60 years. Multivariate analyses identified low serum bilirubin (<1 mg/dl) as an independent factor associated with the emergence of the YMDD motif mutation in patients aged >or=60 years.

CONCLUSIONS

Our results suggest that treatment with lamivudine is both well tolerated and efficacious in elderly patients with chronic HBV infection.

A novel accurate ACRS-PCR method with a digestion internal control for identification of wild type and YMDD mutants of hepatitis B virus strains

As a consequence of the point mutation in the YMDD motif of the hepatitis B virus (HBV) polymerase gene, lamivudine-resistant mutants have been reported in chronic hepatitis B patients who underwent lamivudine therapy. The objective of the study was to develop a novel accurate artificially created restriction site (ACRS) method with a digestion internal control for identification of YMDD, YIDD and YVDD HBV strains. Three conserved, specific and diagnostic primers introducing NdeI, SspI and AleI cleavage sites were designed in order to identify YMDD, YIDD and YVDD strains, respectively; while, their reverse primers also modified with the above recognition sites in order to enzyme correctness monitoring and false outcome avoiding. Thirty-two chronic hepatitis B patients who had taken lamivudine for 1-3 years and checked by the Inno-LiPA HBV DR kit, were evaluated by the ACRS method and then compared to sequencing data. The results of the ACRS method revealed the YMDD mutant strain in 20 patients, YMDD plus YIDD pattern in 1 patient, YMDD plus YVDD in 4 patients, the YIDD in 4 patients and mixed infection with each three strains in 1 patient. The sequencing and Inno-LiPA results were in agreement with the ACRS results. The novel ACRS method is a reliable, rapid and a cost-effective technique for determination of HBV strains with the wild type and YMDD mutant patterns.

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Long-Term Lamivudine Treatment is Associated with a Good Maintained Response in Severe Acute Exacerbation of Chronic Hbeag-Negative Hepatitis B

Hepatitis B e antigen (HBeAg)-negative chronic hepatitis B is difficult to treat and there is little long-term data for lamivudine treatment of severe acute exacerbation. We report a prospective, consecutive cohort of severe acute exacerbation of HBeAg-negative chronic hepatitis B patients treated by lamivudine between 1999 and 2004. All patients had respectively increased alanine aminotransferase and serum bilirubin to at least 10 and 2 times the upper limit of laboratory normal. Thirty-two patients were treated with lamivudine for 130 ±58 (range 48–217) weeks. Five patients had evidence of virological breakthrough (HBV DNA >10,000 copies/ml) during lamivudine treatment. The cumulative probability of maintained response without any virological breakthrough was 94% (95% confidence interval [CI], 86–100%) at year 1, 94% (95% CI, 82–100%) at year 2 and 71% (95% CI, 41–100%) at year 3. At the last follow-up visit, 31 (97%) lamivudine patients had HBV DNA <10,000 copies/ml. The prevalence of lamivudine resistance mutation was 1 in 32 patients (3%; 95% CI, 0–9%) at year 1, 1 in 17 patients (6%; 95% CI, 0–17%) at year 2, 1 in 9 patients (11%, 95% CI, 0–32%) at year 3 and 1 in 4 patients (25%; 95% CI, 0–67%) at year 4 of lamivudine treatment. In conclusion, extended lamivudine treatment is associated with a high maintained virological response and a low rate of drug resistance in severe acute exacerbation of HBeAg-negative chronic hepatitis B.

Long-term results of lamivudine monotherapy in Korean patients with HBeAg-positive chronic hepatitis B: response and relapse rates, and factors related to durability of HBeAg seroconversion

OBJECTIVE

The aim of this study was to evaluate retrospectively the long-term effects of lamivudine in 461 Korean patients with chronic hepatitis B who were treated for more than 12 months.

METHODS

The annual rates of virological response and breakthrough were examined and the predictive factors for post-treatment relapse in 114 patients who achieved hepatitis B e antigen (HBeAg) loss or seroconversion after lamivudine therapy were also analyzed.

RESULTS

During follow-up, the rates of HBeAg seroconversion after 1, 2, 3, 4 and 5 years of treatment were 22.9, 33.2, 47.6, 54.2 and 58.8%, respectively, while those for virological breakthrough at 1, 2, 3 and 4 years were 8.2, 41.7, 55.7 and 64.8%, respectively. Ninety-five patients (20.6%) had HBeAg seroconversion and 19 (4.1%) showed HBeAg loss alone with disappearance of hepatitis B virus DNA in serum. Seroconversion was higher with prolonged treatment in patients who had elevated serum alanine aminotransferase. The cumulative relapse rates in the seroconversion group were 52.0 and 55.7% 1 and 2 years after treatment, respectively. Age and the duration of additional treatment were significant predictive factors for post-treatment relapse. Patients aged </=40 who had additional treatment for >12 months after seroconversion had the lowest relapse rate (p < 0.001).

CONCLUSIONS

These results suggest that additional treatment for over 12 months after HBeAg seroconversion in younger patients may produce a better long-term outcome.

Virological and biochemical relapse after discontinuation of lamivudine monotherapy for chronic hepatitis B in Japan: comparison with breakthrough hepatitis during long-term treatment

OBJECTIVE

Comparison of virological and biochemical relapse in patients with chronic hepatitis B, based on continuation or discontinuation of lamivudine monotherapy.

METHODS

In Japanese genotype C-dominant hepatitis B patients, 25 patients who stopped treatment at normal levels of alanine transferase (ALT) were retrospectively compared with 75 patients who continued treatment. Both groups were matched for age, sex, and observation period after start of treatment. We investigated the relapse rates, and evaluated predictive factors for relapse and efficacy of retreatment of the discontinuous group.

RESULTS

Virological and biochemical relapse occurred significantly earlier in the discontinuous than continuous group, and the peak levels and ratios of peak to pretreatment levels of serum bilirubin and ALT after relapse were not significantly different between the two groups. Multivariate analysis identified three independent factors at discontinuation of treatment associated with early biochemical relapse: HBeAg positivity, presence of liver cirrhosis, detection of basic core promoter mutant. Normalization of ALT levels with retreatment occurred in 62.5% of patients, but 2 HBeAg-positive patients retreated after the emergence of YMDD motif mutant developed severe relapse with hyperbilirubinemia.

CONCLUSION

Our results in Japanese patients with genotype C-dominant hepatitis B suggest that discontinuation of lamivudine monotherapy, and retreatment after the emergence of YMDD mutant should be given attention.

Favorable efficacy of long-term lamivudine therapy in patients with chronic hepatitis B: An 8-year follow-up study

The long-term efficacy of lamivudine therapy in patients with hepatitis B virus (HBV) infection is still not clear. In this study, 20 non-cirrhotic Japanese patients infected with HBV received lamivudine therapy for more than 1 year and were followed for a median period of 8.5 years (range, 6.7-8.7 years). The rates of HBe antigen (HbeAg) negative, HBV-DNA undetectable, and alanine aminotransferase (ALT) normal level at the start of lamivudine were 55%, 25%, and 20% and 85%, 80%, and were 80%, respectively, at the last visit, including patients who received additional treatment. The values at the last visit tended to and were significantly higher than those at the start. The values improved at the last visit regardless of the emergence of YMDD motif mutant and continuation of lamivudine. YMDD mutant and biochemical relapse with mutant virus (breakthrough hepatitis) appeared in 65% and 45% during follow-up, respectively, but severe breakthrough hepatitis occurred in only 5%. Furthermore, 80% of patients who received additional treatment for breakthrough hepatitis, regardless of continuation of lamivudine, were ALT normal level at the last visit, in contrast to 25% untreated. HBsAg clearance occurred in two patients of the discontinuous lamivudine group with non-vertical transmission, who were relatively young. One was infected with HBV genotype C with breakthrough hepatitis and the other had no YMDD mutant and was infected with genotype D, a rare type in Japan. None developed cirrhosis or hepatocellular carcinoma (HCC) during follow-up. Our results suggest that long-term lamivudine therapy improves long-term prognosis, especially when additional treatment for breakthrough hepatitis is used.

Virological and biochemical relapse according to YMDD motif mutant type during long-term lamivudine monotherapy

Whether the type of lamivudine-resistant virus in hepatitis B virus (HBV) influences the clinical outcome, it is not completely understood. We evaluated the serial changes in YMDD motif mutant in 60 Japanese genotype C-HBV patients who received long-term lamivudine monotherapy. YIDD or YVDD alone tended to stop shifting to the mixed type (YVDD and YIDD) within 12 months after the detection of mutant virus. Hence, the characteristics, virological relapse (DNA breakthrough) and biochemical relapse (breakthrough hepatitis) of 49 patients, who could be classified into three types (continuous YVDD, continuous YIDD, and the mixed type), were investigated. YVDD and YIDD type tended to have the opposite background with regard to age, histology, and viral load. The mixed and YIDD types tended to have similar backgrounds, except for viral load. In the mixed type, both the HBeAg-positive rate and viral load as risk factors for emergence of the mutant tended to be high. Mutant virus, DNA breakthrough and breakthrough hepatitis emerged significantly earlier in the mixed type than the two other types. The incidence of severe breakthrough hepatitis accompanied by icteric flare-up tended to be higher in the mixed type than the other types. Our results suggest that the YMDD motif mutant type might emerge from different backgrounds and modulate the virological and biochemical relapse after the emergence. Large-scale studies of each mutant type should be conducted in the future to confirm these findings.