BACKGROUNDTenofovir disoproxil (TDF) is a promising salvage therapy for patients with chronic hepatitis B (CHB) who failed regimens of other nucleoside analogues (NAs). In this study, we aimed to investigate the clinical efficacy and safety of TDF monotherapy in Chinese CHB patients with genotypic resistance.

METHODSA total of 33 CHB patients who had failed treatment with other NAs and had genotypic resistance were switched to TDF monotherapy for 48 weeks. Patients' demographic data (age, sex, history of hepatitis B virus [HBV] therapy), laboratory testing results (hepatitis B e antigen [HBeAg] status, HBV DNA levels, alanine aminotransferase [ALT] levels, serum creatinine, urinary protein, genotypic assay), clinical symptoms, and liver color ultrasound examinations were collected for evaluation at day 0 (baseline) and the 12th, 24th, 36th, and 48th weeks after initiating treatment. Statistical analyses were carried out using rank sum test or rank correlation.

RESULTSWith regard to efficacy, the study found that all patients who switched to TDF monotherapy had undetectable HBV DNA levels after 48 weeks. In addition, patients with lower baseline HBV DNA levels realized earlier virological undetectability (rs = 0.39, P = 0.030). ALT levels were normal in 30 of 33 patients (91%). HBeAg negative conversion occurred in 7 of 25 patients (28%), among whom HBeAg seroconversion (12%) and HBeAg seroclearance (16%) occurred. The time of complete virological response was significantly affected by the number of resistance loci (rs = 0.36, P = 0.040). Concerning safety, the study found that no adverse events were observed during the 48 weeks.

CONCLUSIONTDF monotherapy is an effective and safe salvage treatment for CHB patients who are resistant to other NAs.

Adult ; Anti-HIV Agents ; adverse effects ; therapeutic use ; DNA, Viral ; genetics ; Drug Resistance, Viral ; Female ; Genotype ; Hepatitis B virus ; drug effects ; pathogenicity ; Hepatitis B, Chronic ; drug therapy ; Humans ; Male ; Middle Aged ; Prospective Studies ; Tenofovir ; adverse effects ; therapeutic use

BACKGROUND/AIMS: To analyze the effects of preexisting lamivudine (LAM) resistance and applying antiviral treatment (adefovir [ADV] add-on LAM combination treatment) on long-term treatment outcomes, and comparing the clinical outcomes of antiviral-naïve chronic hepatitis B patients receiving entecavir (ETV) monotherapy. METHODS: This study enrolled 73 antiviral-naïve patients who received 0.5-mg ETV as an initial therapy and 54 patients who received ADV add-on LAM combination treatment as a rescue therapy from July 2006 to July 2010. RESULTS: During 24-month treatments, the decreases in serum log10HBV-DNA values (copies/mL) were significantly greater in the antiviral-naïve patients treated with ETV than the patients receiving ADV add-on LAM combination treatment. The biochemical response rates for alanine aminotransferase normalization at 6 months (ETV) and 12 months (ADV add-on LAM) were 90.4% (66/73) and 77.8% (42/54), respectively (P=0.048). A Kaplan-Meier analysis indicated that the rates of serologic response, viral breakthrough, and emergence of genotypic resistance did not differ significantly between the two patient groups. There were also no significant intergroup differences in the rates of disease progression (PD) and new development of hepatocellular carcinoma (HCC). CONCLUSION: The long-term clinical outcomes of antiviral-naïve patients treated with ETV and LAM-resistant patients receiving ADV add-on LAM combination treatment were comparable in terms of the emergence of HCC and disease progression.
Adenine/*analogs & derivatives/pharmacology/therapeutic use ; Adult ; Alanine Transaminase/blood ; Antibodies, Viral/blood ; Antiviral Agents/*therapeutic use ; DNA, Viral/blood ; Disease Progression ; Drug Resistance, Viral/drug effects ; Drug Therapy, Combination ; Female ; Follow-Up Studies ; Genotype ; Guanine/analogs & derivatives/pharmacology/therapeutic use ; Hepatitis B e Antigens/blood ; Hepatitis B virus/drug effects/genetics/isolation & purification ; Hepatitis B, Chronic/*drug therapy ; Humans ; Lamivudine/pharmacology/therapeutic use ; Male ; Middle Aged ; Organophosphonates/pharmacology/*therapeutic use ; Treatment Outcome

BACKGROUND/AIMS: Tenofovir disoproxil fumarate (TDF) exhibits similar antiviral efficacy against treatment-naïve and lamivudine (LAM)-resistant chronic hepatitis B (CHB). However, there are few clinical reports on the antiviral effects of TDF-LAM combination therapy compared to TDF monotherapy in patients with LAM-resistant CHB. METHODS: We investigated the antiviral efficacy of TDF monotherapy vs. TDF-LAM combination therapy in 103 patients with LAM-resistant CHB. RESULTS: The study subjects were treated with TDF alone (n=40) or TDF-LAM combination therapy (n=63) for ≥6 months. The patients had previously been treated with TDF-based rescue therapy for a median of 30.0 months (range, 8-36 months). A virologic response (VR) was achieved in 99 patients (96.1%): 95.0% (38/40) of patients in the TDF monotherapy group and 96.8% (61/63) of patients in the TDF-LAM combination therapy group. The VR rates were not significantly different between the TDF monotherapy and TDF-LAM combination therapy groups (88.9 vs. 87.3% at month 12, and 94.4 vs. 93.7% at month 24, log-rank p=0.652). Univariate and multivariate analyses revealed that none of the pretreatment factors were significantly associated with VR. CONCLUSIONS: TDF monotherapy was as effective as TDF-LAM combination therapy for maintaining viral suppression in the vast majority of patients with LAM-resistant CHB, which suggests that TDF add-on therapy with LAM is unnecessary.
Adult ; Aged ; Aged, 80 and over ; Antiviral Agents/pharmacology/*therapeutic use ; DNA, Viral/blood ; Drug Administration Schedule ; Drug Resistance, Viral/drug effects ; Drug Therapy, Combination ; Female ; Hepatitis B virus/genetics ; Hepatitis B, Chronic/*drug therapy ; Humans ; Kidney Function Tests ; Lamivudine/*therapeutic use ; Liver Function Tests ; Male ; Middle Aged ; Polymerase Chain Reaction ; Tenofovir/*therapeutic use ; Treatment Outcome

OBJECTIVETo investigate distinctive features in drug-resistant mutations (DRMs) and interpretations for reverse transcriptase inhibitors (RTIs) between proviral DNA and paired viral RNA in HIV-1-infected patients.

METHODSForty-three HIV-1-infected individuals receiving first-line antiretroviral therapy were recruited to participate in a multicenter AIDS Cohort Study in Anhui and Henan Provinces in China in 2004. Drug resistance genotyping was performed by bulk sequencing and deep sequencing on the plasma and whole blood of 77 samples, respectively. Drug-resistance interpretation was compared between viral RNA and paired proviral DNA.

RESULTSCompared with bulk sequencing, deep sequencing could detect more DRMs and samples with DRMs in both viral RNA and proviral DNA. The mutations M184I and M230I were more prevalent in proviral DNA than in viral RNA (Fisher's exact test, P<0.05). Considering 'majority resistant variants', 15 samples (19.48%) showed differences in drug resistance interpretation between viral RNA and proviral DNA, and 5 of these samples with different DRMs between proviral DNA and paired viral RNA showed a higher level of drug resistance to the first-line drugs. Considering 'minority resistant variants', 22 samples (28.57%) were associated with a higher level of drug resistance to the tested RTIs for proviral DNA when compared with paired viral RNA.

CONCLUSIONCompared with viral RNA, the distinctive information of DRMs and drug resistance interpretations for proviral DNA could be obtained by deep sequencing, which could provide more detailed and precise information for drug resistance monitoring and the rational design of optimal antiretroviral therapy regimens.

Adult ; Antiviral Agents ; pharmacology ; China ; DNA, Viral ; genetics ; metabolism ; Drug Resistance, Viral ; genetics ; Female ; HIV Infections ; drug therapy ; HIV-1 ; drug effects ; genetics ; metabolism ; High-Throughput Nucleotide Sequencing ; Humans ; Male ; Middle Aged ; Mutation ; Proviruses ; genetics ; metabolism ; RNA, Viral ; genetics ; metabolism ; RNA-Directed DNA Polymerase

A549 Cells ; Animals ; Drug Evaluation, Preclinical ; Drug Resistance, Viral ; drug effects ; Humans ; Influenza A virus ; metabolism ; Mice, Inbred BALB C ; Orthomyxoviridae Infections ; drug therapy ; metabolism ; Sesterterpenes ; chemistry ; pharmacology

Animals ; Dogs ; Drug Resistance, Viral ; drug effects ; Female ; Humans ; Influenza A Virus, H7N9 Subtype ; Madin Darby Canine Kidney Cells ; Male ; Orthomyxoviridae Infections ; drug therapy ; Ribavirin ; pharmacology

BACKGROUND/AIMS: To investigate the association between the baseline profiles and dynamics of hepatitis B virus (HBV) DNA polymerase gene mutations and the long-term virological response of lamivudine (LAM)-adefovir (ADV) combination therapy in patients with LAM-resistant chronic hepatitis B. METHODS: Seventy-five patients who received LAM-ADV combination therapy for more than 12 months were analyzed. Restriction fragment mass polymorphism assays were used to detect and monitor the dynamics of LAM- and ADV-resistant mutations. RESULTS: The median duration of LAM-ADV combination therapy was 26 months (range, 12 to 58 months). The baseline mutation profiles, rtM204I (p=0.992), rtM204I/V (p=0.177), and rtL180M (p=0.051), were not correlated with the cumulative virological response, and the baseline HBV DNA level (p=0.032) was the only independent predictive factor for cumulative virological response. Tests for LAM- and ADV-resistant mutations were performed in 12 suboptimal responders in weeks 48 and 96. The population of rtM204 mutants persisted or increased in 8 of 12 patients, and rtA181T mutants newly emerged as a minor population in four patients until 96 weeks. Nevertheless, the viral loads progressively decreased during rescue therapy, and these dynamics did not correlate with virological response. CONCLUSIONS: The baseline profile and dynamics of LAM-resistant mutations during LAM-ADV combination therapy are not associated with a virological response.
Adenine/administration & dosage/*analogs & derivatives/therapeutic use ; Adult ; Aged ; Aged, 80 and over ; Antiviral Agents/administration & dosage/*therapeutic use ; DNA-Directed DNA Polymerase/genetics ; Drug Resistance, Viral/genetics ; Drug Therapy, Combination ; Female ; Hepatitis B virus/*genetics ; Hepatitis B, Chronic/*drug therapy/virology ; Humans ; Lamivudine/administration & dosage/*therapeutic use ; Male ; Middle Aged ; Organophosphonates/administration & dosage/*therapeutic use ; Treatment Outcome ; Viral Load/drug effects ; Young Adult

BACKGROUND/AIMS: The efficacy of tenofovir disoproxil fumarate (TDF) for the treatment of chronic hepatitis B (CHB) patients following prior treatment failure with multiple nucleos(t)ide analogues (NAs) is not well defined, especially in Asian populations. In this study we investigated the efficacy and safety of TDF rescue therapy in CHB patients after multiple NA treatment failure. METHODS: The study retrospectively analyzed 52 CHB patients who experienced failure with two or more NAs and who were switched to regimens containing TDF. The efficacy and safety assessments included hepatitis B virus (HBV) DNA undetectability, hepatitis B envelop antigen (HBeAg) seroclearance, alanine transaminase (ALT) normalization and changes in serum creatinine and phosphorus levels. RESULTS: The mean HBV DNA level at baseline was 5.4 +/- 1.76 log10 IU/mL. At a median duration of 34.5 months of TDF treatment, the cumulative probabilities of achieving complete virological response (CVR) were 25.0%, 51.8%, 74.2%, and 96.7% at 6, 12, 24, and 48 months, respectively. HBeAg seroclearance occurred in seven of 48 patients (14.6%). ALT levels were normalized in 27 of 31 patients (87.1%) with elevated ALT at baseline. Lower levels of HBV DNA at baseline were significantly associated with increased CVR rates (p < 0.001). However, CVR rates did not differ between TDF monotherapy or combination therapy with other NAs, and were not affected by mutations associated with resistance to NAs. No significant adverse events were observed. CONCLUSIONS: TDF is an efficient and safe rescue therapy for CHB patients after treatment failure with multiple NAs.
Adenine/adverse effects/*analogs & derivatives/therapeutic use ; Adult ; Aged ; Alanine Transaminase/blood ; Antiviral Agents/adverse effects/*therapeutic use ; Biological Markers/blood ; Creatinine/blood ; DNA, Viral/blood ; Drug Resistance, Viral/genetics ; Drug Substitution ; Female ; Genotype ; Hepatitis B e Antigens/blood ; Hepatitis B virus/*drug effects/genetics/immunology/pathogenicity ; Hepatitis B, Chronic/blood/diagnosis/*drug therapy ; Humans ; Kaplan-Meier Estimate ; Male ; Middle Aged ; Mutation ; Phosphorous Acids/adverse effects/*therapeutic use ; Phosphorus/blood ; Retrospective Studies ; Time Factors ; Treatment Failure ; Viral Load ; Young Adult

OBJECTIVETo determine the prevalence of mutations in the non-structural protein 5B (NS5B) of the hepatitis C virus (HCV),which are associated with natural resistance to non-nucleoside and nucleoside polymerase inhibitors (PIs),in treatment-naive hepatitis C patients in south China.

METHODSA nested PCR protocol that amplified three different regions of NS5B was used to detect the naturally occurring drag-resistant substitutions.Direct PCR sequencing was performed to analyze the sequences.

RESULTSNS5B mutations known to confer resistance to nucleoside PIs,such as A15G,S96T and S282T,were mainly detected in HCV genotype 6a (20/88,22.73%).Of the NS5B mutations known to confer resistance to non-nucleoside PIs,C316N and S365A were detected in HCV genotype lb (60/60,100% and 2/60,3.33%, respectively) and I482L and V499A were mainly detected in HCV genotype 2a (9/9,100% and 4/4,100%, respectively) and HCV genotype 6a (9/9,100% and 4/4,100%, respectively).Other NS5B mutations found in the study population included A1 5S,S365F,S365P,S368A and S368L;although none of these has been previously shown to confer resistance to PIs.

CONCLUSIONNaturally occurring dominant PI resistance mutations in NS5B exist in treatment-na(i)ve hepatitis C patients in south China and may be related to the virus genotype.

Antiviral Agents ; pharmacology ; China ; Drug Resistance, Viral ; Genotype ; Hepacivirus ; drug effects ; genetics ; Hepatitis C ; drug therapy ; virology ; Humans ; Mutation ; Viral Nonstructural Proteins ; genetics

BACKGROUNDIt has been reported that several baseline polymorphisms of direct-acting antivirals (DAAs) agents resistance-associated variants (RAVs) would affect the treatment outcomes of patients chronically infected with hepatitis C virus (CHC). The aim of this study is to investigate the prevalence of DAAs RAVs in treatment-naÏve GT1b CHC patients.

METHODSDirect sequencing and ultra-deep sequencing of the HCV NS3, NS5A, and NS5B gene were performed in baseline serum samples of treatment-naÏve patients infected with genotype 1b hepatitis C virus (HCVs).

RESULTSOne hundred and sixty CHC patients were studied. Complete sequence information was obtained for 145 patients (NS3), 148 patients (NS5A), and 137 patients (NS5B). Treatment-failure associated variants of DAAs were detected: 56.6% (82/145) of the patients presented S122G for simeprevir (NS3 protease inhibitor); 10.1% (14/148) of the patients presented Y93H for daclatasvir and ledipasvir (NS5A protein inhibitors); 94.2% (129/137) of the patients presented C316N for sofosbuvir (NS5B polymerase inhibitor). Nearly, all of the DAAs RAVs detected by ultra-deep sequencing could be detected by direct sequencing.

CONCLUSIONSThe majority of genotype 1b CHC patients in China present a virus population carrying HCV DAAs RAVs. Pretreatment sequencing of HCV genome might need to be performed when patients infected with GT1b HCV receiving DAAs-containing regimens in China. Population sequencing would be quite quantified for the work.

Adult ; Aged ; Antiviral Agents ; therapeutic use ; Benzimidazoles ; therapeutic use ; China ; Drug Resistance, Viral ; genetics ; Female ; Fluorenes ; therapeutic use ; Genotype ; Hepacivirus ; drug effects ; pathogenicity ; Hepatitis C ; drug therapy ; High-Throughput Nucleotide Sequencing ; Humans ; Imidazoles ; therapeutic use ; Male ; Middle Aged ; Polymorphism, Genetic ; genetics ; Simeprevir ; therapeutic use