Lamivudine Therapy Research Articles

Infectious Diseases Risk While on Chronic, High-Dose Corticosteroids

Infectious Diseases Risk While on Chronic, High-Dose Corticosteroids

Detection of Hepatitis B Virus M204I Mutation by Quantum Dot-Labeled DNA Probe.

Quantum dots (QDs) are semiconductor nanoparticles with a diameter of less than 10 nm, which have been widely used as fluorescent probes in biochemical analysis and vivo imaging because of their excellent optical properties. Sensitive and convenient detection of hepatitis B virus (HBV) gene mutations is important in clinical diagnosis. Therefore, we developed a sensitive, low-cost and convenient QDs-mediated fluorescent method for the detection of HBV gene mutations in real serum samples from chronic hepatitis B (CHB) patients who had received lamivudine or telbivudine antiviral therapy. We also evaluated the efficiency of this method for the detection of drug-resistant mutations compared with direct sequencing. In CHB, HBV DNA from the serum samples of patients with poor response or virological breakthrough can be hybridized to probes containing the M204I mutation to visualize fluorescence under fluorescence microscopy, where fluorescence intensity is related to the virus load, in our method. At present, the limits of the method used to detect HBV genetic variations by fluorescence quantum dots is 103 IU/mL. These results show that QDs can be used as fluorescent probes to detect viral HBV DNA polymerase gene variation, and is a simple readout system without complex and expensive instruments, which provides an attractive platform for the detection of HBV M204I mutation.

The nucleotide changes within HBV core promoter/precore during the first 12 weeks of nucleos(t)ide treatment might be associated with a better virological response

ObjectivesWe aimed to study the dynamic changes of hepatitis B virus (HBV) core promoter/precore (CP/preC) sequences during antiviral treatment and their associations with virological responses. Materials and methodsThe baseline and 12-week CP/preC sequences (nts 1655–2014) were obtained from 52 chronic hepatitis B patients with positive hepatitis B e antigen (HBeAg), who received a 104-week lamivudine and adefovir dipivoxil combination therapy. The mutations within the CP/preC were analyzed against genotype specific reference sequences. The nucleotide change rates in individuals during therapy were analyzed in a pairwise comparison manner. ResultsThere was no significant difference of the mutation rate at each nucleotide site between baseline and week 12 of treatment (P>0.05). The mutation rates of A1762T/G1764A and G1896A were found to decrease from 46.2% (24/52) at baseline to 36.5% (19/52) at week 12 (P=0.426) and from 28.8% (15/52) to 21.2% (11/52) (P=0.497), respectively. The nucleotide change rates varied from 0.0% - 7.8% in individuals [0.0% in Group 1 (N=26); 0.3% - 7.8% in Group 2 (N=26)] during the first 12-week treatment. HBV DNA levels in Group 2 were significantly lower than those in Group 1 throughout therapy (P<0.01) (e.g., 1.5±1.3log10 IU/ml vs. 2.6±1.0log10 IU/ml at week 104, P=0.001). At week 104 the rates of HBV DNA undetectable and HBeAg loss in Group 2 were significantly higher than those in Group 1 (P<0.05). Along with the increased nucleotide change rates, the rate of HBV DNA undetectable at week 104 tended to increase (odds ratio=0.323, 95% confidence interval=0.138–0.758, P<0.001). ConclusionOur findings suggested that the nucleotide changes within HBV CP/preC region during the first 12-week treatment might be associated with a better virological response.

Unusual case of lamivudine-associated skin rashes in an HIV/AIDS patient: a case presentation

In patients with human immunodeficiency virus (HIV) infection, lamivudine is used as a first-line drug for antiretroviral therapy. Lamivudine is relatively nontoxic in nature, and it can also be used during pregnancy. Herein, we describe a 43-year-old, HIV-positive female hospitalized with maculopapular, pruritic rash that appeared first on the extremities and gradually spread with systemic symptoms such as fever and myalgia after lamivudine therapy.

Lamivudine therapy during the second vs the third trimester for preventing transmission of chronic hepatitis B.

There are little data on the timing of initiating lamivudine therapy for preventing transmission of hepatitis B in highly viremic mothers. Between May 2008 and January 2015, we retrospectively enrolled mothers with HBV DNA >6log10 copies/mL who received lamivudine during pregnancy, and we compared them to untreated mothers. The primary measurement was the vertical transmission rate. The secondary outcomes were the mothers' and infants' safety. Among 249 consecutive mothers enrolled, 66 and 94 received lamivudine during the second and third trimesters, respectively, and 89 were untreated. At delivery, maternal mean HBV DNA levels were significantly lower in mothers who received lamivudine (4.45log10; vs 7.16log10 copies/mL; P<.001). Lamivudine treatment was well tolerated. However, early treatment during the second trimester did not significantly increase the percentage of mothers achieving HBV DNA levels of <6log10 copies/mL compared to those treated during the third trimester (98.5% vs 94.7%; P=.40). At the age of 28weeks, the vertical transmission rates were significantly lower in the lamivudine-treated mothers vs in the untreated mothers (0% [0/160] vs 5.62% [5/89]; P<.001), but the rates were similar when comparing the two subgroups treated with lamivudine (0% [0/66] vs 0% [0/94], P>.05). The birth defect rates and mothers' and infants' adverse events were similar among the groups. Lamivudine treatment initiated in the second or third trimester for mothers with HBV DNA levels below 9log10 copies/mL was equally safe and effective in preventing vertical transmission. Thus, lamivudine should be deferred until the third trimester to minimize foetal exposure and drug resistance.

Efficacy of long-term tenofovir-based rescue therapy in patients with chronic hepatitis B refractory to nucleoside/nucleotide analogs.

Few studies have investigated the efficacy of long-term tenofovir disoproxil fumarate (TDF)-based rescue therapy in patients with chronic hepatitis B refractory to nucleoside/nucleotide analogs. We retrospectively analyzed 40 Japanese patients with chronic hepatitis B refractory to nucleoside/nucleotide analogs who received TDF-based rescue therapy [TDF monotherapy, TDF plus lamivudine (LAM) combination therapy, or TDF plus entecavir (ETV) combination therapy] followed up for a median of 45 months (range 14-99months). Viral response, changes in hepatitis B surface antigen levels from the baseline, and viral breakthrough during therapy were analyzed. The proportion of patients with undetectable serum hepatitis B virus (HBV) DNA levels (less than 2.1 log copies per milliliter) (viral response) during TDF-based rescue therapy was 68, 78, 85, 88, 83, 81, 88, and 100% at 0.5, 1, 1.5, 2, 2.5, 3, 3.5, and 4years respectively. There were no differences in the viral response rate between the TDF plus LAM group and the TDF plus ETV group. The mean reduction from the baseline in hepatitis B surface antigen levels in patients with LAM-resistant HBV was greater than the reductions in patients with adefovir dipivoxil (ADV)-resistant or ETV-resistant HBV at 2 and 3years (P=0.024, and P=0.025 respectively). However, two patients with ADV- or ETV-resistant HBV at the baseline developed viral breakthrough during TDF-based rescue therapy. Long-term therapy with a TDF-based rescue regimen demonstrated high viral suppression in patients in whom LAM plus ADV combination therapy, ETV plus ADV combination therapy, or ETV monotherapy had failed. However, patients with ADV- or ETV-resistant HBV at the baseline may develop viral breakthrough and resistance, and careful follow-up is advised.

Monitoring of genotypic resistance profile in chronic hepatitis B patients receiving nucleos(t)ide analogues in Huzhou, China.

Antiviral drug-resistance patterns of hepatitis B virus (HBV) mutants are complex and currently partly understood. The aim of this study was to monitor the genotypic resistance profile in patients with chronic hepatitis B (CHB) receiving nucleos(t)ide analogues (NAs) in Huzhou, eastern China. Serum samples of 139 CHB patients undergoing NA treatment were obtained from Huzhou Central Hospital. The full-length HBV reverse transcriptase regions were amplified and sequenced. The NA resistance mutation positions, including rtL80, rtI169, rtV173, rtL180, rtA181, rtT184, rtA194, rtS202, rtM204, rtI233, rtN236, and rtM250 were analyzed. Genotypic resistance mutations were detected in 41.72% (58/139) of patients with CHB. Drug resistance mutations were detected at positions rt80, rt173, rt180, rt181, rt194, rt202, rt204, rt236, and rt250, but were not observed at positions rt169, rt184, and rt233. The prevalence of mutations at rtM204 was 54.44% in 90 patients who were treated with lamivudine (LAM) or telbivudine (LDT). RtN236 mutations were detected in 7.14% (2/28) of the patients receiving adefovir (ADV) therapy. Additionally, rtA181 mutations were observed in 4 patients with LAM, ADV, and LDT-based therapy, but not in those patients treated with entecavir (ETV). Among patients who harbored rtM204 combination mutations, rtM204I and rtM204V were significantly associated with rtL80I/V and rtL180M, respectively. The mutation patterns of NA-resistant HBV are complicated in CHB patients in the current clinical setting. Thus, it is necessary to persistently monitor the resistance mutations of HBV for optimizing antiviral therapy strategy and for preventing an outbreak of clinical resistance.

Prevalence and risk factors for viral blipping in chronic hepatitis B patients treated with nucleos (t) ide analogues.

The clinical relevance of viral blipping during nucleos (t) ide analogue (NA) treatment is unclear in chronic hepatitis B (CHB). We investigated the prevalence, risk factors and clinical outcomes for those with viral blipping during NA treatment. A retrospective cohort study investigated consecutively treated CHB patients from May 2008 to February 2015 on the NAs such as entecavir (ETV), tenofovir (TDF) and lamivudine (LAM). Included patients were previously treatment naive. Viral blipping was defined as serum HBV DNA >20IU/mL on one occasion, and not >200IU/mL, with subsequent measurement returning to undetectable levels, that is <20IU/mL. A total of 242 treatment-compliant CHB patients were included with 44 (18.2%) experiencing viral blipping. In multivariable Cox regression, Asian race (HR=7.40, 95% CI 1.01-54.29, P<.049), LAM therapy (vs ETV/TDF, HR=2.53, 95% CI 1.29-4.95, P<.007), higher creatinine (per SD, HR=1.47, 95% CI 1.21-1.79, P<.001), HBeAg positivity (HR=2.68, 95% CI 1.39-5.03, P<.003) and longer time to achieve undetectable HBV DNA (per month, HR=1.05, 95% CI 1.02-1.08, P=.001) were associated with an increased risk of viral blipping. Viral blipping did not show any significant association with viral breakthrough, HBsAg loss, ALT flares or disease progression. Viral blipping is a frequent event during NA therapy; however, it did not lead to any clinically significant outcomes. Thus, it may not require more frequent blood work and patient visits in clinical practice.

Durability of the virological response after lamivudine discontinuation in lamivudine-resistant patients with a complete virological response after lamivudine and adefovir combination therapy.

We investigated the durability of virological response after lamivudine (LAM) discontinuation in LAM-resistant chronic hepatitis B (CHB) patients with complete virological response after LAM-adefovir (ADV) combination therapy. We enrolled 58 patients switched to ADV monotherapy with undetectable viral loads (<12 IU/ml) and normal alanine aminotransferase levels after ADV add-on combination treatment for at least 6 months in LAM-resistant CHB patients. Virologic relapse was defined as HBV DNA detection at more than 20 IU/ml by quantitative polymerase chain reaction determined on two consecutive measurements. During median 40.9 months of follow-up (range 11.5-79.0 months), seven (12.1%) patients experienced virological relapse. The cumulative rate of virological relapse at 3 and 5 years was 5.5% and 22.4%, respectively. Two patients had elevated alanine aminotransferase during virological relapse. These seven patients with virological relapse had undetectable HBV DNA after switching to tenofovir therapy. In our study, switching to ADV monotherapy resulted in sustained HBV DNA suppression in 87.9% of the patients during median 40.9 months follow-up. This adapting step-down strategy, switching from combination therapy to monotherapy in virologically suppressed CHB patients with stable liver disease, may reduce the cost burden and the risk of potentially harmful effects of combination therapy. J. Med. Virol. 89:85-90, 2017. © 2016 Wiley Periodicals, Inc.

Long‐term lamivudine therapy in chronic hepatitis B

One to 5years of therapy of chronic hepatitis B with oral nucleoside analogues result in significant clinical improvements, but effects of more prolonged therapy are not well defined. To describe outcomes of chronic hepatitis B with long-term lamivudine therapy. Forty-two patients with chronic hepatitis B treated with lamivudine were followed for 3.2-19.5 (median=16.1)years. Therapy was switched to other agents (n=16) if patients developed lamivudine resistance and relapse of disease. Among 22 HBeAg-positive patients, 17 (77%) became HBeAg negative, of whom 5 (23%) subsequently cleared HBsAg. Among 20 HBeAg-negative patients, 10 (50%) cleared HBsAg. The time to HBsAg clearance ranged from 0.9 to 16.8 (median=9.3) years. Lamivudine resistance arose in 24 patients (57%) of whom 6 (25%) lost HBsAg. HBsAg clearance was not always accompanied by seroconversion; anti-HBs appearing concurrently in only five patients (33%). Nevertheless, HBsAg loss allowed for stopping therapy in all patients, none re-developing HBsAg or suffering relapse; all having normal alanine aminotransferase levels and no (n=13) or unquantifiable HBV DNA levels (n=2) when last seen. In contrast, seven of 27 patients (26%) who remained HBsAg-positive died of liver disease or liver cancer or underwent liver transplantation, all of whom had cirrhosis. Long-term viral suppression with nucleoside analogues leads to HBsAg loss in a substantial proportion of patients, particularly if HBeAg-negative. Serious outcomes during the first 10-20years of treatment occur largely among patients with pre-existing cirrhosis who do not clear HBsAg with therapy.

Association between clinical features and YMDD mutations in patients with chronic hepatitis B following lamivudine therapy.

The aim of the present study was to investigate the correlation between feature and genotype with regard to the tyrosine-methionine-aspartate-aspartate (YMDD) mutation in chronic hepatitis B patients after lamivudine (LAM) therapy. A total of 30 patients with chronic hepatitis B were recruited, who underwent one year of LAM therapy. The patients' alanine aminotransferase (ALT) level and hepatitis B envelope antigen (HBeAg) seroconversion were evaluated, hepatitis B virus (HBV) DNA was genotyped using a new genotyping method and YMDD mutations were analyzed prior to treatment and at 6 and 12 months after LAM treatment. Furthermore, the secondary protein structure of the HBV DNA polymerase gene (P gene) was analyzed. Following treatment, the results suggested that LAM therapy improved ALT normalization. There was no correlation between clinical effects and ALT level before treatment. After 12 months treatment, the rate of HBeAg loss increased and the rate of HBeAg seroconversion decreased linearly with the rise of baseline ALT level. While ALT normalization and HBeAg seroconversion were highest in patients with HBV genotype B, HBeAg loss and HBVDNA loss were highest in those with genotype C. The effect was predominant in genotype D. No YMDD mutations were identified prior to 6 months of LAM therapy. The rate of YMDD mutations after 12 months LAM therapy was 12.12%. Two patients with rtM204V + rtL180M belonged to genotype C and another patient with rtL180M alone belonged to genotype D. The turn of secondary protein structure of P gene changed to β sheet when a rtM204V mutation occurred, and no change of secondary protein structure was associated with the rtL180M mutation. Thus, the present results indicate that one year of LAM therapy is able to improve ALT normalization. Long-term LAM therapy may induce YMDD mutation and drug resistance.

Dynamic Characteristics of Serum Hepatitis B Surface Antigen in Chinese Chronic Hepatitis B Patients Receiving 7 Years of Entecavir Therapy.

Background:The ultimate goal of hepatitis B treatment is hepatitis B surface antigen (HBsAg) seroclearance. Several factors have been suggested to be associated with the rate of HBsAg reduction in antiviral-naive or lamivudine therapy cohorts. However, there are few studies evaluating the factors during long-term entecavir (ETV) therapy. In the present study, we aimed to evaluate the factors to predict the outcome of ETV therapy for 7 years.Methods:A total of 47 chronic hepatitis B (CHB) patients treated with ETV monotherapy were included in this study. Liver biochemistry, hepatitis B virus (HBV) serological markers, serum HBV DNA, and HBsAg titers were tested at baseline, 3 months, 6 months, and yearly from 1 to 7. The associations between factors and HBsAg reduction were assessed using multivariate tests with repeated measure analysis of variance.Results:At baseline, serum HBsAg levels showed a positive correlation with baseline HBV DNA levels (r = 0.625, P < 0.001). The mean HBsAg titers after ETV treatment were significantly lower than the baseline titers (P ranges from 0.025 to 0.000,000,6). The HBsAg reduction rate during the 1st year was greater compared to after 1 year of treatment (P < 0.05). Multivariate test showed that hepatitis B e antigen (HBeAg) seroclearance and/or HBsAg reduction ≥0.5 log10 IU/ml at 6 months had a high negative predictive value (96.77%) for HBsAg seroclearance (P = 0.002, P = 0.012, respectively).Conclusions:The HBsAg reduction rate during the 1st year was greater than that after 1 year of treatment. Further, HBeAg status and HBsAg levels at month 6 are the optimal factors for the early prediction of HBsAg seroclearance after long-term ETV therapy in CHB patients.

Long-term efficacy of Peg-Interferon/Ribavirin with and without Lamivudine therapy for HBeAg-positive hepatitis B and C dual infection.

The optimal therapeutic strategy for hepatitis B virus (HBV) e antigen (HBeAg)-seropositive and hepatitis C virus (HCV) dually infected patients remains unknown. We aimed to elucidate the effectiveness of peginterferon (Peg-IFN)/ribavirin (RBV) with and without lamivudine (LAM) combination therapy in the clinical settings. Nine patients seropositive for HBV surface antigen, HBeAg, antibodies to HCV and HCV RNA for >6 months were treated with Peg-IFN/RBV with (n = 5) and without (n = 4) a 12-month LAM add-on therapy at treatment week 12. The treatment duration of Peg-IFN/RBV was 24 weeks (HCV genotype 1 [HCV-1] with rapid virological response [RVR] or HCV-2) or 48 weeks (HCV-1 without RVR). Primary endpoints included HBeAg loss and HCV-sustained virological response (SVR). All of the nine patients had undetectable HCV RNA at treatment weeks 4 and 12 and end-of-Peg-IFN/RBV therapy. However, SVR was achieved in 100% of patients treated with triple therapy, compared with only 50% in those with Peg-IFN/RBV therapy (P = 0.167). The 3-year durability of HCV SVR was 100%. HBeAg loss and HBV DNA <2000 IU/mL at 6 months post-LAM treatment were found in 100% and 40% of patients treated with triple therapy, compared with none of the four patients with Peg-IFN/RBV therapy achieved any HBV responses. Of the five patients with triple therapy, four had persistent HBeAg loss during 3-year follow-up period; one developed HBeAg seroreversion 15 months after treatment. For HBeAg-positive HBV/HCV dually infected patients, Peg-IFN/RBV was effective for HCV eradication. Add-on LAM might promote HBeAg loss in the clinical setting.

Evaluation of pharmacokinetics underlies the collaborated usage of lamivudine and oxymatrine in beagle dogs

Combinational therapy of lamivudine and oxymatrine has been employed in the battle against hepatitis B virus in clinical setting. However, the pharmacokinetic behavior of the drug or active metabolism in intravenous/oral co-administration regime is poorly investigated. Herein, we evaluated the pharmacokinetic characteristic through a tailor-designed 3 way crossover-Latin square experiment in adult male beagle dogs. Six dogs were randomly treated by intravenous administration of lamivudine (2.5 mg/kg), oxymatrine (15 mg/kg) and combinational dosage, named as intravenous regime. Meanwhile the other six dogs were orally administrated with lamivudine (2.5 mg/kg), oxymatrine (15 mg/kg) and combinational dosage, named as oral regime. The pharmacokinetic feature in simultaneous oral treatment appeared to have no significant difference when compared with individual administration, even including matrine, the active metabolite of oxymatrine. In intravenous regime, the main pharmacokinetic parameters of simultaneous administration were nearly consistent with intravenous regime remedy. The collaborated application of lamivudine and oxymatrine contributed to non-distinctive pharmacokinetic fluctuations of beagle dogs in intravenous/oral regime, compared with individual employment, which established a vital base for the clinical co-administration against hepatitis B. Furthermore, the present study demonstrated that the determination of pharmacokinetics between combinational and individual therapy might assist in the development of drug compatibility in clinical therapy.

Sequential Treatment with Lamivudine and Peg-interferon Therapy in Patients with E-positive Chronic Hepatitis B and High Viral Load

Sequential Treatment with Lamivudine and Peg-interferon Therapy in Patients with E-positive Chronic Hepatitis B and High Viral Load

Predictors of hepatitis B e antigen-negative hepatitis in chronic hepatitis B virus-infected patients from childhood to adulthood.

Hepatitis B e antigen (HBeAg)-negative hepatitis is a clinical indicator of poor outcome for chronic hepatitis B viral (HBV) infection. This long-term prospective cohort study aimed to elucidate the predictors of developing HBeAg-negative hepatitis in chronic HBV-infected subjects followed from childhood to adulthood. We followed 434 HBeAg-positive chronic HBV-infected patients from a median age of 7.22 years (interquartile range 4.31-10.21 years). Spontaneous HBeAg seroconversion occurred in 359 subjects at a median age of 13.93 years (interquartile range 8.76-20.59 years), and 75 subjects developed HBeAg seroconversion after antiviral therapy. These patients were followed for a median of 14.40 years (interquartile range 6.14-22.02 years) after HBeAg seroconversion. Clinical data were analyzed to delineate the predictors of developing HBeAg-negative hepatitis. The HBV basal core promoter and precore/core gene sequences were also evaluated in subjects with and without HBeAg-negative hepatitis. The overall annual incidence of HBeAg-negative hepatitis was 0.37% (95% confidence internal 0.35-0.39) in spontaneous HBeAg seroconverters. The overall annual incidence of HBeAg-negative hepatitis increased to 2.64% in lamivudine-treated subjects but did not increase in those treated with interferon-alpha (0.58%). Male gender (hazard ratio = 3.15), HBV genotype C (hazard ratio = 4.40), HBeAg seroconversion after 18 years of age (hazard ratio = 2.46), and lamivudine therapy prior to HBeAg seroconversion (hazard ratio = 1.42) were predictors of HBeAg-negative hepatitis in HBeAg seroconverters (P < 0.05). HBeAg-negative hepatitis subjects carried more A1762T/G1764A, C2063A, and A2131C HBV gene mutations than those without HBeAg-negative hepatitis. HBeAg seroconversion during childhood predicts a lower risk of HBeAg-negative hepatitis in later life. Interferon-alpha therapy may be an effective antiviral therapy beneficial in chronic HBV-infected children with severe inflammation that facilitates HBeAg seroconversion in earlier life.

Lamivudine Therapy Exacerbates Bilirubinemia in Patients Underlying Severely Advanced Hepatitis

Lamivudine belongs to the set of antiviral agents effective against hepatitis B virus infection. Given case reports on liver injuries after certain antiviral agent treatments, this study examined the effects of lamivudine on alanine aminotransferase (ALT) and total bilirubin (TB) using a medical system database. A total of 1,321 patients taking lamivudine alone or with others were evaluated using laboratory hits in an electronic medical system at Seoul National University Hospital from 2005 through 2011. The patients were grouped according to prior ALT results: G#1, ALT lt; 40 IU/L; G#2, 40 IU/L ≤ ALT lt; 120 IU/L; G#3, 120 IU/L ≤ ALT lt; 240 IU/L; and G#4, ALT ≥ 240 IU/L. In G#1 and G#2 patients, lamivudine or adefovir treatment decreased ALT and TB compared to prior values. In G#3 and G#4 patients with three times the upper limit of normal (ULN) ≤ ALT lt; 15 times the ULN, both ALT and TB were decreased after treatment with lamivudine alone, or adefovir following lamivudine therapy, indicating that lamivudine therapy ameliorated liver functions. However, in G#4 patients who experienced severely advanced hepatitis (ALT ≥ 15 times the ULN, or ≥ 600 IU/L), lamivudine augmented TBmax (6.3 → 13.3 mg/dL) despite a slight improvement in ALT (839 → 783 IU/L), indicative of exacerbation of bilirubinemia. Patients who used adefovir after lamivudine also showed a high incidence of hyperbilirubinemia when they experienced severely advanced hepatitis. Treatment with adefovir alone did not show the effect. In conclusion, lamivudine may increase the risk of hyperbilirubinemia in patients with severely advanced hepatitis, implying that caution should be exercised when using lamivudine therapy in certain patient populations.

The clinical implication of single nucleotide polymorphisms in deoxycytidine kinase in chronic hepatitis B patients treated with lamivudine.

Deoxycytidine kinase (dCK) is a critical enzyme involved in intracellular phosphorylation of lamivudine (LAM) to its active triphosphates. We conducted this study to determine dCK polymorphisms in Koreans and to evaluate whether the discovered single nucleotide polymorphisms (SNPs) were associated with treatment outcomes in chronic hepatitis B (CHB) patients treated with LAM. The full-length dCK gene was sequenced from 24 healthy volunteers and 24 patients with CHB. One hundred twenty-seven patients with CHB who were followed-up for at least 24 months after LAM treatment were enrolled. Virological response as determined by undetectable HBV DNA was defined as a good drug response. Primary non-response at 6 months and virological breakthrough within 12 months were defined as a poor drug response. Six novel dCK SNPs were found (-2052C/A, IVS3 - 46G/del, IVS4 + 40G/T, IVS5 + 39T/C, IVS5 - 72A/T, and 966-975T10/T11). In particular, two promoter SNPs, namely -360C/G and -201C/T, were in full linkage disequilibrium. These two SNPs had a higher allele frequency than previously reported in Caucasian, Japanese, and Chinese (26% vs. 2%, 13.1%, and 15.6%, respectively). There was no significant difference between treatment response groups in terms of the distributions of SNP genotypes or allele frequencies. However, there was significant difference in the allele frequency of -360G/-201T between HBeAg seroclearance group and HBeAg non-seroclearance group (P = 0.045). In conclusion, six novel dCK SNPs were discovered. Two promoter SNPs, namely -360C/G and -201C/T, were more frequent in Koreans than other populations. In particular, HBeAg-positive patients with the -360G/-201T haplotype may help HBeAg seroclearance in response to LAM therapy.

Evaluation of hepatitis B virus transmission and antiviral therapy among hepatitis B surface antigen-positive pregnant women.

The aim of the present study was to assess the potential risk of hepatitis B virus (HBV) vertical transmission among Turkish parturient women and to evaluate the efficacy and safety of antiviral agents. Data were collected retrospectively from 114 HBV-infected pregnant women and their infants in eight health institutions in Turkey. The baseline characteristics of the women were: mean age, 28.3 ± 5.2 years; alanine aminotransferase, 57.4 ± 139.0 U/L; aspartate aminotransferase, 56.6 ± 150.0 U/L; and HBV DNA, 8.3 × 10(7) ± 2.6 × 10(8) copies/mL. Family history of HBV infection was detected in 53.5% (n = 61). In total, 60 (52.6%) pregnant women received tenofovir (60.0%), lamivudine (33.3%) or telbivudine (6.7%) therapy at the median gestational age of 22.2 ± 8.5 (1-36) weeks. All infants were vaccinated and hepatitis B immune globulin was administered, with 81 of them (71.1%) available for follow-up. After completion of HBV vaccination course, 71 (87.7%) infants had protective anti-HBs levels, three (3.7%) were hepatitis B surface antigen-positive, and seven (8.6%) were hepatitis B surface antigen-negative with nonprotective anti-HBs levels. Five of the infants had low gestational birthweight but no other birth defects were observed. According to our results, viral load may not be the only effecting factor for transmission of HBV to children of infected mothers. Pregnant women with high viral load should be followed-up closely during pregnancy. They should begin to take tenofovir or telbivudine, which are category B drugs for pregnancy, at the beginning of the third trimester at the latest. We need new treatment strategies; and close follow-up of mothers and children is another important issue.

Lamivudine Resistance and Precore Variants in Iranian Patients With Chronic Hepatitis B: Correlation With Virological and Clinical Features.

Background:Long-term lamivudine therapy, despite its initial effectiveness against hepatitis B virus (HBV), is associated with the emergence of drug resistance mutations in polymerase protein.Objectives:The aim of the present study was to determine the prevalence of precore and lamivudine drug resistance mutations in lamivudine treated patients with chronic B hepatitis.Patients and Methods:Sequential sera were obtained from 88 chronic HBV carriers who received lamivudine for more than 24 months. Polymerase and precore regions were directly sequenced for these groups: I (before treatment), II, and III (12 and 24 months after treatment, respectively).Results:All patients (100%) were contained genotype D, subtype ayw2. One (1.1%), 12 (13.6%), and 22 (25%) members of groups I, II, and III had the replacement of either isoleucine or valine instead of methionine in tyrosine-methionine-aspartate-aspartate (YMDD) motif, respectively. The frequency of mutations from 0 time point to 12 and 24 months showed that there was an increasing trend between sequential samples (P < 0.001). In group I, 31 (35.2%); II, 36 (41.0%) and III, 41 (46.6%) members had the precore stop codon mutations. The frequency of mutations from 0 time point to 12 and 24 months showed that there was an ascending trend between sequential samples. Indeed, frequency of precore stop codon was significantly increased with the passage of time (P < 0.001).Conclusions:Presence of drug resistance mutations among the patients was significant. Precore mutations were common amongst Iranian HBV chronic carriers under lamivudine therapy and these mutations were accompanied by clinical relapse.