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| adefovir |
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| CHEBI:2469 |
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| A member of the class of phosphonic acids that is methylphosphonic acid in which one of the methyl hydrogens has been replaced by a 2-(6-amino-9H-purin-9-yl)ethoxy group. An inhibitor of HIV-1 reverse transcriptase, the bis(t-butoxycarbonyloxymethyl) ester (dipivoxil ester) prodrug is used to treat chronic hepatitis B viral infection. |
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This entity has been manually annotated by the ChEBI Team.
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CHEBI:40188
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| ChemicalBook:CB2698137, eMolecules:901335, ZINC000021297308 |
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more structures >>
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| Adefovir is a prescription medicine used to treat (chronic) infections with hepatitis B virus. A prodrug form of adefovir was previously called bis-POM PMEA, with trade names Preveon and Hepsera. It is an orally administered nucleotide analog reverse-transcriptase inhibitor (ntRTI). It can be formulated as the pivoxil prodrug adefovir dipivoxil. |
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Read full article at Wikipedia
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InChI=1S/C8H12N5O4P/c9- 7-6-8(11-3-10-7)13(4-12-6)1-2-17-5-18(14,15)16/h3-4H,1-2,5H2,(H2,9,10,11)(H2,14,15,16) |
| SUPKOOSCJHTBAH-UHFFFAOYSA-N |
| N1(C2=C(C(N)=NC=N2)N=C1)CCOCP(O)(=O)O |
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HIV-1 reverse transcriptase inhibitor
An entity which inhibits the activity of HIV-1 reverse transcriptase.
drug metabolite
antiviral drug
A substance used in the prophylaxis or therapy of virus diseases.
nephrotoxic agent
A role played by any chemical compound (natural or synthetic) exhibiting itself through the ability to induce damage to the kidneys.
DNA synthesis inhibitor
Any substance that inhibits the synthesis of DNA.
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antiviral drug
A substance used in the prophylaxis or therapy of virus diseases.
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View more via ChEBI Ontology
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{[2-(6-amino-9H-purin-9-yl)ethoxy]methyl}phosphonic acid
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9-(2-(Phosphonomethoxy)ethyl)adenine
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ChemIDplus
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9-(2-Phosphonylmethoxyethyl)adenine
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KEGG COMPOUND
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9-(2-Phosphonylmethoxyethyl)adenine
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ChemIDplus
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Adefovir
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KEGG COMPOUND
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DRG-0156
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ChemIDplus
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GS 0393
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ChemIDplus
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GS 393
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ChemIDplus
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GS-0393
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ChemIDplus
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HSDB 8079
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ChemIDplus
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N-(2-Phosphonylmethoxyethyl)adenine
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ChemIDplus
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PMEA
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KEGG COMPOUND
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5HG
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PDBeChem
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Adefovir
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Wikipedia
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C11277
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KEGG COMPOUND
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D02768
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KEGG DRUG
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DB00718
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DrugBank
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| View more database links |
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106941-25-7
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CAS Registry Number
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KEGG COMPOUND
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106941-25-7
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CAS Registry Number
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ChemIDplus
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3561094
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Reaxys Registry Number
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Reaxys
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Lee SH, Cheon GJ, Kim HS, Kim SG, Kim YS, Jeong SW, Jang JY, Kim BS, Jun BG, Don Kim Y, Jun DW, Sohn JH, Kim TY, Lee BS (2018)
Tenofovir disoproxil fumarate monotherapy is superior to entecavir-adefovir combination therapy in patients with suboptimal response to lamivudine-adefovir therapy for nucleoside-resistant HBV: a 96-week prospective multicentre trial.
Antiviral therapy 23, 219-227 [PubMed:28436380]
[show Abstract]
BackgroundA complete virological response is closely related to the long-term outcome of patients with chronic hepatitis B and prevention of emerging HBV mutations. We aimed to evaluate the efficacy of tenofovir disoproxil fumarate (TDF) monotherapy compared to entecavir-adefovir dipivoxil (ETV-ADV) combination therapy in patients with suboptimal responses to long-term lamivudine-adefovir dipivoxil (LAM-ADV) therapy for nucleoside analogue-resistant chronic hepatitis B.MethodsPatients (n=60) were randomized to TDF monotherapy or ETV-ADV combination therapy for 96 weeks. All patients had the rt204I/V mutation and serum HBV DNA was measured (>60 IU/ml) during LAM-ADV therapy. The primary end point was a complete virological response (HBV DNA <20 IU/ml) at week 96.ResultsThe median duration of prior LAM-ADV rescue therapy was 43 (7-108) months. A complete virological response was achieved in 86.6% and 53.3% of patients in the TDF and ETV-ADV groups, respectively, at week 96 (P=0.005). Reduction in serum HBV DNA was significantly greater in the TDF group than in ETV-ADV group (-3.2 ±1.2 versus -2.6 ±1.2; P=0.01). Hepatitis B e antigen loss (22.2% versus 16.6%; P=0.731) and biochemical responses (76.7% versus 73.3%; P=0.766) were not different between the TDF and ETV-ADV groups. No newly emerged mutations were detected. Both therapies demonstrated favourable safety profiles.ConclusionsTDF therapy achieved a better complete virological response than ETV-ADV therapy in chronic hepatitis B patients with suboptimal response to long-term LAM-ADV rescue therapy. (KCT0000627). | Vincenti D, Piselli P, Solmone M, D'Offizi G, Capobianchi MR, Menzo S (2017)
Evolutionary trends of resistance mutational patterns of HBV reverse transcriptase over years (2002-2012) of different treatment regimens: The legacy of lamivudine/adefovir combination treatment.
Antiviral research 143, 62-68 [PubMed:28322924]
[show Abstract]
Antiviral therapy has revolutionized treatment of chronic HBV infections. First generation compounds, lamivudine and adefovir, displayed a high rate of treatment failures, and have been replaced by more potent compounds with high genetic barrier to resistance. However, the evolution of the virus towards resistance due the use of first generation compounds may still provide useful information for a better management of current antivirals. A single center sequence database including 705 HBV reverse transcriptase sequences from patients failing antiviral treatments (2002-2012) has been statistically analyzed to highlight viral evolution in relationship to the use of antiviral compounds and to their associations/sequencing in those years. The influence of viral genotypes and polymorphisms on resistance-related mutational patterns was also investigated. This study documents how, after the first years of antiviral therapy, the use of adefovir as an add-on strategy allowed a consistent reduction treatment failures. It also documents the effects of the initial misuse of entecavir in lamivudine experienced patients. In the latest years, the correct use of entecavir and the introduction of tenofovir allowed further curbing of resistance-related treatment failures, which virtually disappeared. Furthermore, the study allows a better understanding of how viral genotype (A vs D) conditions specific mutational pathways to resistance against lamivudine and entecavir, and demonstrates that the use of adefovir in lamivudine experienced patients is associated to peculiar mutational patterns, in particular A181V + F/Y221L. Despite some concern may arise for patients previously treated with lamivudine/adefovir, in sequence or combination, where the virus may have developed a lower genetic barrier against resistance to tenofovir, the outlook of antiviral treatment of HBV infection should be quite optimistic. | Yamamoto T, Maruyama Y, Ohashi N, Yasuda H, Shinozaki M (2017)
Hypophosphatemia predicts a failure to recover from adefovir-related renal injury after dose reduction in lamivudine-resistant hepatitis B patients.
Hepatology research : the official journal of the Japan Society of Hepatology 47, 1272-1281 [PubMed:28079295]
[show Abstract]
AimIn chronic hepatitis B patients receiving 10 mg adefovir, dose reduction is recommended when renal injury appears. However, recovery is not always achieved and markers that recommend switching to another antiviral agent are unknown. We investigated adefovir-related renal injury, recovery after dose reduction, and their predictors.MethodsThe renal injury in 77 chronic hepatitis B patients receiving 10 mg adefovir and recovery after dose reduction to alternate day administration in those with adefovir-related renal injury were assessed. The predictors for >20% estimated glomerular filtration rate (eGFR) decline following treatment with 10 mg adefovir and for >20% eGFR recovery after dose reduction were investigated.ResultsThe adefovir dose was reduced in 26 patients (34%) at 59 ± 30 (mean ± standard deviation) months of 10 mg adefovir treatment because of decreases in eGFR (cumulative incidence 27%), serum phosphorus (9%), and uric acid (16%) levels, and increases in alkaline phosphatase (20%), bone type alkaline phosphatase (18%), urinary α1-microglobulin (18%), and urinary N-acetyl-β-D-glucosaminidase (18%) levels. The only significant predictor for >20% eGFR decline was age ≥50 years at the start of 10 mg adefovir treatment. The cumulative eGFR recovery rate was 42% at 42 ± 27 months after dose reduction, and ≥2.5 mg/dL serum phosphorus level at dose reduction was the only significant predictor for >20% eGFR recovery after dose reduction.ConclusionPatients aged ≥50 years are predisposed to adefovir-related renal injury and switching to another antiviral agent rather than adefovir dose reduction is recommended when hypophosphatemia is observed. | Lin Y, Pan F, Wang Y, Chen Z, Lin C, Yao L, Zhang X, Zhou R, Pan C (2017)
Adefovir dipivoxil-induced Fanconi syndrome and its predictive factors: A study of 28 cases.
Oncology letters 13, 307-314 [PubMed:28123560]
[show Abstract]
The aim of the present study was to identify monitoring and prevention measures as well as predictive factors for early detection of renal toxicity associated with long-term administration of adefovir dipivoxil in order to avoid progression to Fanconi syndrome. Clinical data of 28 patients with Fanconi syndrome caused by long-term administration of adefovir dipivoxil for the treatment of chronic hepatitis B virus (HBV) infection were collected pre-and post-administration for analysis. Patients presented with fatigue, progressive systemic pain in multiple bones and joints, as well as difficulty in walking and pathological fractures in a number of severe cases. Laboratory examinations revealed hypophosphatemia, elevated serum cystatin C (Cys-C), elevated serum creatinine (SCr), reduced glomerular filtration rate (GFR), positive urinary protein, erythrocytes and glucose, as well as osteoporosis. In consequence, adefovir dipivoxil administration was stopped, and patients received concentrated divitamins, sodium phosphate syrup and calcitriol. Symptoms and abnormalities in laboratory examinations were significantly improved in all patients after 2-6 months. Therefore, serum phosphate, SCr, routine urine parameters, Cys-C and GFR should be monitored regularly in chronic HBV patients treated with adefovir dipivoxil. The following factors were identified as predictive of kidney damage and Fanconi syndrome: Age ≥40 years, living in rural areas, previous renal toxicity, estimated GFR (eGFR) <90 ml/min/1.73 m2, hypertension, diabetes, cirrhosis and duration of adefovir dipivoxil treatment exceeding 24 months. The present results indicate that timely termination of adefovir dipivoxil treatment and replacement with other antiviral agents is critical once renal impairment appears, and that it is necessary to change to other antiviral agents and prolong the interval of administration according to the eGFR level. | Zhao X, Sun K, Lan Z, Song W, Cheng L, Chi W, Chen J, Huo Y, Xu L, Liu X, Deng H, Siegenthaler JA, Chen L (2017)
Tenofovir and adefovir down-regulate mitochondrial chaperone TRAP1 and succinate dehydrogenase subunit B to metabolically reprogram glucose metabolism and induce nephrotoxicity.
Scientific reports 7, 46344 [PubMed:28397817]
[show Abstract]
Despite the therapeutic success of tenofovir (TFV) for treatment of HIV-1 infection, numerous cases of nephrotoxicity have been reported. Mitochondrial toxicity has been purported as the major target of TFV-associated renal tubulopathy but the underlying molecular mechanism remains unclear. In this report, we use metabolomics and proteomics with HK-2 cells and animal models to dissect the molecular pathways underlying nephropathy caused by TFV and its more toxic analog, adefovir (ADV). Proteomic analysis shows that mitochondrial chaperone TRAP1 and mtDNA replicating protein SSBP1 were significantly down-regulated in TFV and ADV treated HK-2 cells compared with controls. Transmission electron microscopy (TEM) revealed that TFV and ADV-treated HK-2 cells had accumulated glycogen, a phenotype that was also observed in mice treated with TFV and ADV. Analysis of the proteins in TCA cycle showed succinate dehydrogenase subunit B (SDHB) was nearly depleted in glucose oxidative phosphorylation pathway however certain enzymes in the glycolysis and glycogen synthesis pathway had elevated expression in TFV and ADV-treated HK-2 cells. These results suggest that TFV and ADV may cause mitochondrial dysfunction in renal tubular cells and reprogramming of glucose metabolism. The resulting glycogen accumulation may partially contribute to TFV and ADV induced renal dysfunction. | Yang S, Xing H, Wang Q, Wang X, Liu S, Cheng J (2016)
De novo entecavir+adefovir dipivoxil+lamivudine triple-resistance mutations resulting from sequential therapy with adefovir dipivoxil, and lamivudine.
Annals of clinical microbiology and antimicrobials 15, 24 [PubMed:27079793]
[show Abstract]
BackgroundEntecavir-resistance mutations are commonly induced by entecavir treatment in chronic hepatitis B patients. However, entecavir+adefovir dipivoxil+lamivudine triple-resistance mutations induced by sequential or combination treatment with lamivudine and adefovir dipivoxil have never been reported.ResultsWe retrospectively reviewed 1200 patients who had been tested for anti-HBV drug resistance at Beijing Ditan Hospital of Capital Medical University, and five patients showing multidrug resistance to lamivudine and adefovir dipivoxil were enrolled. Stored serum samples were used for genetic analysis, which yielded a total of 135 clones. Entecavir+adefovir dipivoxil+lamivudine triple-resistance mutations were identified in 60 % (3/5) entecavir-naïve patients who received sequential therapy with adefovir dipivoxil and lamivudine. Specifically, we found one rtM204I+rtL180 M+rtM250 V+rtA181 V clone among 23 clones from patient 1 (4.35 %), one rtM204 V+vrtL180 M +rtM250 V+rtA181 V clone among 24 clones from patient 2 (4.17 %), and 2 clones harboring rtM204 V+rtL180 M+rtM250 V+rtA181 V and rtM204 V+rtL180 M+rtI169 V+rtA181 V among 20 clones from patient 3 (10.0 %). The other 2 patients showed multidrug resistance after lamivudine/telbivudine and adefovir dipivoxil combination therapy, but no entecavir-resistance mutations were found in these two patients.ConclusionDe novo entecavir+adefovir dipivoxil+lamivudine triple-resistance mutations can be induced by sequential therapy with adefovir dipivoxil and lamivudine in patients who never take entecavir. These results provide important information for sequential therapy with adefovir dipivoxil and lamivudine and the use of entecavir as a rescue therapy for these patients with multidrug resistance. | Laho T, Clarke JD, Dzierlenga AL, Li H, Klein DM, Goedken M, Micuda S, Cherrington NJ (2016)
Effect of nonalcoholic steatohepatitis on renal filtration and secretion of adefovir.
Biochemical pharmacology 115, 144-151 [PubMed:27381944]
[show Abstract]
Background and aimsAdefovir, an acyclic nucleotide reverse transcriptase inhibitor used to treat hepatitis B viral infection, is primarily eliminated renally through cooperation of glomerular filtration with active tubular transport. Nonalcoholic steatohepatitis is a variable in drug disposition, yet the impact on renal transport processes has yet to be fully understood. The goal of this study was to determine the effect of nonalcoholic steatohepatitis on the pharmacokinetics of adefovir in rats given a control or methionine and choline deficient diet to induce nonalcoholic steatohepatitis.MethodsAnimals received a bolus dose of 7mg/kg (35μCi/kg) [(3)H] adefovir with consequent measurement of plasma and urine concentrations. Inulin clearance was used to determine glomerular filtration rate.ResultsMethionine and choline deficient diet-induced nonalcoholic steatohepatitis prolonged the elimination half-life of adefovir. This observation occurred in conjunction with reduced distribution volume and hepatic levels of adefovir. Notably, despite these changes, renal clearance and overall clearance were not changed, despite markedly reduced glomerular filtration rate in nonalcoholic steatohepatitis. Alteration of glomerular filtration rate was fully compensated for by a significant increase in tubular secretion of adefovir. Analysis of renal transporters confirmed transcriptional up-regulation of Mrp4, the major transporter for adefovir tubular secretion.ConclusionsThis study demonstrates changes to glomerular filtration and tubular secretion that alter pharmacokinetics of adefovir in nonalcoholic steatohepatitis. Nonalcoholic steatohepatitis-induced changes in renal drug elimination processes could have major implications in variable drug response and the potential for toxicity. | Wei Z, He JW, Fu WZ, Zhang ZL (2016)
Osteomalacia induced by long-term low-dose adefovir dipivoxil: Clinical characteristics and genetic predictors.
Bone 93, 97-103 [PubMed:27664568]
[show Abstract]
ContextAdefovir dipivoxil (ADV) was an important cause of adult-onset hypophosphatemic osteomalacia. However, its clinical characteristics and mechanisms have not been well defined.ObjectiveThe objective of the study was to summarize the clinical characteristics of ADV-induced osteomalacia and to explore the association between ADV-associated tubulopathy and polymorphisms in genes encoding drug transporters.Design, setting, patients, and main outcome measureSeventy-six affected patients were clinically studied. The SLC22A6 and ABCC2 genes were screened and compared with healthy people from the HapMap.ResultsHypophosphatemia, high serum alkaline phosphatase (ALP) levels, hypouricemia, nondiabetic glycosuria, proteinuria, metabolic acidosis and high bone turnover markers were the main metabolic characteristics. Fractures and pseudofractures occurred in 39 patients. Stopping ADV administration, supplementing calcitriol and calcium was effective during the follow-up period. Single SNP analysis revealed a higher percentage of the G/A genotype at c.2934 in exon 22 of the ABCC2 gene (rs3740070) in patients than in healthy people (12% [7 of 58 patients] vs. 0% [0 of 45 patients]; P=0.017), while there was no subject with homozygosity for the A allele at c.2934.ConclusionsADV can be nephrotoxic at a conventional dosage. The G/A genotype at c.2934 of the ABCC2 gene may be a predictor of patients at greater risk for developing ADV-associated tubulopathy. Larger case-control studies are needed to further verify this finding. | Kim HJ, Park SK, Yang HJ, Jung YS, Park JH, Park DI, Cho YK, Sohn CI, Jeon WK, Kim BI, Choi KY (2016)
Comparison of the clinical outcomes between antiviral-naïve patients treated with entecavir and lamivudine-resistant patients receiving adefovir add-on lamivudine combination treatment.
Clinical and molecular hepatology 22, 350-358 [PubMed:27729626]
[show Abstract]
Background/aimsTo 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.MethodsThis 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.ResultsDuring 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).ConclusionThe 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. | Lee HW, Park JY, Kim BK, Kim MY, Lee JI, Kim YS, Yoon KT, Han KH, Ahn SH (2016)
Efficacy of switching from adefovir to tenofovir in chronic hepatitis B patients who exhibit suboptimal responses to adefovir-based combination rescue therapy due to resistance to nucleoside analogues (SATIS study).
Clinical and molecular hepatology 22, 443-449 [PubMed:27880997]
[show Abstract]
Background/aimsIt remains to be determined whether switching from adefovir (ADV) to tenofovir (TDF) provides better virological outcomes in patients exhibiting suboptimal responses to ADV plus nucleoside analogue (ADV+NA) therapy for NA-resistant chronic hepatitis B (CHB).MethodsIn this prospective trial, patients who showed partial responses (defined as serum hepatitis B virus [HBV] DNA >60 IU/mL) to ADV+NA therapy for NA resistance were randomly allocated to receive TDF plus NA (TDF+NA group, n=16) or to continue their current therapy (ADV+NA group, n=16). The primary end point was the proportion of patients with complete virological response (CVR, defined as serum HBV DNA <60 IU/mL) at 48 weeks.ResultsThe median age was 52 years (16 men), and 28 were positive for hepatitis B e antigen (HBeAg). The baseline characteristics did not differ significantly between the two groups. The proportion with CVR was significantly higher in the TDF+NA group than in the ADV+NA group at 24 weeks (81.3% vs. 25.0%, P=0.001) and 48 weeks (87.5% vs. 37.5%, P=0.002). Furthermore, a decrease in the serum HBV DNA level of >2log10 IU/mL was more likely in the TDF+NA group at both 24 and 48 weeks (68.8% vs. 56.3%, P=0.014 vs. 81.3% vs. 56.3%, P=0.001, respectively). During the follow-up, the rate of HBeAg seroconversion was higher in the TDF+NA group than the ADV+NA group (12.5% vs. 6.25%, P=0.640), as was that for the hepatitis B surface antigen (6.25% vs. 0%, P=0.080). No serious adverse events due to antiviral agents occurred.ConclusionIn patients exhibiting suboptimal responses to ADV+NA therapy for NA-resistant CHB, switching from ADV to TDF might provide better virological outcomes. | Song BC (2016)
Switch to tenofovir-based therapy or to continue adefovir-based therapy in CHB patients with suboptimal response to adefovir-based combination?
Clinical and molecular hepatology 22, 439-442 [PubMed:28081595] | Tian L, Fu Q, Huang F (2016)
Effect of adefovir dipivoxil on T cell immune function in the treatment of chronic hepatitis B and hepatocirrhosis.
Experimental and therapeutic medicine 12, 2511-2514 [PubMed:27698751]
[show Abstract]
The aim of the present study was to investigate the T cell immune function in chronic hepatitis B hepatocirrhosis patients at the compensated and decompensated stage following treatment with adefovir dipivoxil. A total of 104 patients diagnosed with hepatitis B hepatocirrhosis during the period from October 2013 to October 2014 were enrolled in the study. Among the cases, there were 56 cases at compensated stage, and another 48 at decompensated stage. Adefovir dipivoxil was administered for antiviral therapy (10 mg/time, 1 time/day, for a total of 24 weeks), and we compared the virus disappearance rate, liver function improvement and T cell immune function between the two groups before and after treatment. The difference between the virus disappearance rate in the two groups was not statistically significant (P>0.05). The decreased level of ALT decrease in the compensated group was significantly higher than that in the decompensated group, while the increased level of albumin in the compensated group was significantly higher as well. The differences showed statistical significance (P<0.05). After treatment, the level of CD4+ and CD4+/CD8+ ratio were higher than before treatment, while the level of CD8+ was lower after treatment than before treatment in the two groups. The differences all showed statistical significance (P<0.05). The CD4+CXCR5+ T follicular helper (TFH) cell level in the two groups was higher after treatment, as was interleukin-2 and interferon-γ. The differences all showed statistical significance (P<0.05). As for comparison between groups, the difference had no statistical significance (P>0.05). Adefovir dipivoxil treatment can improve T cell immune function at the compensated and decompensated stages in chronic hepatitis B hepatocirrhosis patients. This may be associated with virus disappearance and liver function improvement. | Hiramatsu R, Ubara Y, Sawa N, Hasegawa E, Kawada M, Imafuku A, Sumida K, Hoshino J, Takaichi K (2016)
Bone Histology of Two Cases with Osteomalacia Related to Low-dose Adefovir.
Internal medicine (Tokyo, Japan) 55, 3013-3019 [PubMed:27746441]
[show Abstract]
We performed a bone histomorphometric analysis in two patients demonstrating Fanconi syndrome with hypophosphatemia, adefovir-related bone disease and chronic hepatitis B infection. Both patients had osteomalacia, but showed two different histological patterns. The osteoid volume of the patient without risedronate increased with [(osteoid volume/ bone volume)×100=18.6%]. However, the osteoid volume of the patient receiving risedronate without vitamin D analogue showed a greater increase of 53.8%. In both patients bone pain and hypophosphatemia subsided soon after the discontinuation of adefovir and the administration of phosphate derivative. These findings show that bisphosphonate may worsen this disease when this drug is administered without a vitamin D analogue. | Ruggiero G, Marrone A, Rainone I, Boemio A, Adinolfi LE, Pasquale G, Rinaldi L, Guerrera B, Andreana L, Zampino R, Thecla Study Group (2016)
Tenofovir disoproxil fumarate monotherapy maintains HBV suppression achieved by a "de novo" combination of lamivudine-adefovir: a pilot study.
Le infezioni in medicina 24, 278-286 [PubMed:28011962]
[show Abstract]
Chronic hepatitis B (CHB) treatment aims at long-term suppression of HBV replication and improvement in clinical outcomes. We describe the data of a pilot, non-profit study in which patients with CHB were treated with de novo combination lamivudine-adefovir (LAM-ADV) for at least four years with a view to HBV suppression and resistance prevention, and shifted to tenofovir (TDF) when new antiviral agents were available. Fifty-one HBeAg negative patients were enrolled. Histology was available for 39 patients and data of liver stiffness (LS) for 24 patients at baseline. Serum quantification of HBsAg and HBVDNA was obtained regularly during the follow-up. In 10 and 7 patients, a paired histology and LS were available at the end of LAM-ADV treatment, respectively. The de novo LAM-ADV combination was able to obtain HBVDNA suppression and ALT normalization in one year in most of the patients and in the second year in the remaining. Histology improved in patients with paired biopsy, but tissue HBsAg was present in all but one patient after 48 months of therapy. TDF maintained biochemical and virological response throughout the follow-up. Renal impairment during LAM-ADV therapy improved on shifting to TDF; only in 4 cases was a second shift to entecavir needed. TDF was safe and effective in maintaining HBV DNA suppression achieved by a long-term course of LAM-ADV de novo combination for the treatment of HBeAg-negative CHB. | Li Z, Shen C, Wang Y, Wang W, Zhao Q, Liu Z, Wang Y, Zhao C (2016)
Circulating kidney injury molecule-1 is a novel diagnostic biomarker for renal dysfunction during long-term adefovir therapy in chronic hepatitis B.
Medicine 95, e5264 [PubMed:27858892]
[show Abstract]
The aim of this study was to evaluate serum kidney injury molecule-1 (KIM-1) as a new diagnostic marker of renal dysfunction in chronic hepatitis B (CHB) patients receiving long-term adefovir dipivoxil (ADV) treatment.We retrospectively enrolled 85 patients treated with ADV and 85 patients treated with entecavir (ETV) monotherapy, for at least 6 months. The 2 groups were matched for baseline age (± 5 years), sex, and estimated glomerular filtration rate (eGFR). Serum creatinine, cystatin C, and KIM-1 concentrations were measured, and eGFR was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine-cystatin C equation, at baseline and last follow-up.eGFR decreased by 10-20% from baseline in 11/85 (14.1%) patients, 20-30% in 5/85 (5.9%), and ≥ 30% in 2/85 (2.4%) patients treated with ADV. Serum KIM-1 was more significantly increased after ADV treatment 86.53 (10.20-355.40) pg/mL than ETV treatment 61.54 (10.53-200.56) pg/mL (P < 0.01). Furthermore, serum KIM-1 was positively correlated with serum cystatin C (r = 0.47; P < 0.001) and negatively correlated with eGFR (r = -0.46; P < 0.001). The area under the receiver operating characteristic curve (AUC-ROC) of serum KIM-1 for identifying renal dysfunction in all enrolled patients was 0.94 (95% confidence interval [95% CI], 0.87 to 1.02; P < 0.001), while the AUC-ROC of serum creatinine was only 0.82 (95% CI, 0.60 to 1.03; P < 0.01).Serum KIM-1 is a promising new diagnostic biomarker of renal dysfunction during long-term ADV therapy for CHB patients. | Luo Q, Deng Y, Cheng F, Kang J, Zhong S, Zhang D, Zeng W (2016)
Relationship between nephrotoxicity and long-term adefovir dipivoxil therapy for chronic hepatitis B: A meta-analysis.
Medicine 95, e5578 [PubMed:27977591]
[show Abstract]
BackgroundTo assess the relationship between adefovir dipivoxil and renal function after anti-hepatitis B virus therapy and elucidate the risk factors involved.MethodsBased on the requirements of the Cochrane systematic review methodology, 21 observational articles on adefovir dipivoxil-associated renal dysfunction were obtained by searching various databases, between January 1, 1995 and July 1, 2016. The Newcastle Ottawa Scale was used to evaluate risk bias. Parameters for 4276 chronic hepatitis B patients were analyzed by Review Manager and R software, and glomerular filtration rate, creatinine clearance, and serum creatinine values were extracted to evaluate renal function.ResultsRenal dysfunction was more likely to occur in patients receiving the adefovir dipivoxil therapy (odds ratio [OR] 1.98, 95% confidence interval [CI] 1.40-2.80) than the none-adefovir dipivoxil group. Subgroup analysis showed that renal function predictive value is higher for glomerular filtration rate (OR 2.42, 95% CI 1.34-3.14), compared with serum creatinine levels (OR 1.51, 95% CI 0.75-3.04). The rate of adefovir dipivoxil-associated renal dysfunction was 12% (95% CI 0.08-0.16). Older patients and patients with renal insufficiency, hypertension, and diabetes mellitus were more prone to developing adefovir dipivoxil-associated renal dysfunction; however, integrated raw data were insufficient for further detailed analysis.ConclusionLong-term adefovir dipivoxil therapy is connected to renal dysfunction in chronic hepatitis B, necessitating the monitoring of kidney function. | Pereira-Gómez M, Bou JV, Andreu I, Sanjuán R (2016)
Lamivudine/Adefovir Treatment Increases the Rate of Spontaneous Mutation of Hepatitis B Virus in Patients.
PloS one 11, e0163363 [PubMed:27649318]
[show Abstract]
The high levels of genetic diversity shown by hepatitis B virus (HBV) are commonly attributed to the low fidelity of its polymerase. However, the rate of spontaneous mutation of human HBV in vivo is currently unknown. Here, based on the evolutionary principle that the population frequency of lethal mutations equals the rate at which they are produced, we have estimated the mutation rate of HBV in vivo by scoring premature stop codons in 621 publicly available, full-length, molecular clone sequences derived from patients. This yielded an estimate of 8.7 × 10-5 spontaneous mutations per nucleotide per cell infection in untreated patients, which should be taken as an upper limit estimate because PCR errors and/or lack of effective lethality may inflate observed mutation frequencies. We found that, in patients undergoing lamivudine/adefovir treatment, the HBV mutation rate was elevated by more than sixfold, revealing a mutagenic effect of this treatment. Genome-wide analysis of single-nucleotide polymorphisms indicated that lamivudine/adefovir treatment increases the fraction of A/T-to-G/C base substitutions, consistent with recent work showing similar effects of lamivudine in cellular DNA. Based on these data, the rate at which HBV produces new genetic variants in treated patients is similar to or even higher than in RNA viruses. | Lin MT, Yen YH, Tsai MC, Tseng PL, Chang KC, Wu CK, Hu TH (2016)
Comparison of the Efficacies and Safety of Combined Therapy between Telbivudine Plus Adefovir and Lamivudine Plus Adefovir in Patients with Hepatitis B Virus Infection in Real-World Practice.
PloS one 11, e0165416 [PubMed:27806120]
[show Abstract]
Background and aimChronic hepatitis B infection remains a significant health issue worldwide. This study evaluated the efficacy and safety of combined therapy using lamivudine plus adefovir (LAM+ADV) versus telbivudine plus adefovir (LdT+ADV) and the corresponding renal function change and safety.MethodsThis study enrolled a total of 171 patients (110 patients received LAM+ADV and 60 patients received LdT+ADV). We analyzed the changes in renal function using the estimated glomerular filtration rate (eGFR). The DNA undetectable rate, hepatitis B e antigen (HBeAg) seroconversion rate, and alanine aminotransferase (ALT) normalization rate were analyzed. We checked the serum uric acid, phosphate and creatine kinase, and lactic acid levels to analyze safety. We observed these patients for 48 to 240 weeks and checked their serum profile every 6 months.ResultsThere was no statistically significant difference between the two groups in anti-hepatitis B virus (HBV) efficacy in terms of DNA undetectable rate, ALT normalization rate, and HBeAg seroconversion rate. Both the LAM+ADV and LdT+ADV groups had stable or improved renal function. However, a higher eGFR was found in the LdT+ADV group with continuous serum fluctuation during 3 years of combined therapy as well as a higher serum creatine kinase level.ConclusionsLong-term LdT+ADV combined therapy and LAM+ADV combined therapy were both associated with stable or improved renal function. The clinical efficacy was similar between the two groups, but the LdT group had a higher serum creatine kinase level. We need to monitor the data regularly in clinical practice. | Liao S, Fan SY, Liu Q, Li CK, Chen J, Li JL, Zhang ZW, Zhang ZQ, Zhong BH, Xie JW (2014)
In vitro evaluation of 9-(2-phosphonylmethoxyethyl)adenine ester analogues, a series of anti-HBV structures with improved plasma stability and liver release.
Archives of pharmacal research 37, 1416-1425 [PubMed:24338503]
[show Abstract]
Chronic hepatitis B virus (HBV) infection may lead to liver cirrhosis and hepatocellular carcinoma, but few drugs are available for its treatment. Acyclic nucleoside phosphonates (ANPs) have remarkable antivirus activities but are not easily absorbed from the gastrointestinal tract and accumulate in the kidneys, resulting in nephrotoxicity. Therefore, there is a need to find effective liver site-specific prodrugs. The dipivaloyloxymethyl ester of 9-(2-phosphonylmethoxyethyl)adenine (PMEA)-adefovir dipivoxil (ADV)-is a first-line therapy drug for chronic hepatitis B with a low therapeutic index because of renal toxicity and low hepatic uptake. In this study, a series of PMEA derivatives were synthesized to enhance plasma stability and liver release. The metabolic stability of ADV (Chemical I) and its two analogues (Chemicals II and III) was evaluated in rat plasma and liver homogenate in vitro. An ion-pair reverse-phase HPLC-UV method and a hybrid ion trap and high-resolution time-of-flight mass spectrometry (LC-IT-TOF-MS) were used to evaluate the degradation rate of the analogues and to identify their intermediate metabolites, respectively. Chemicals I and II were hydrolyzed by cleavage of the C-O bond to give monoesters. Sufficient enzymatic activation in the liver homogenate through a relatively simple metabolic pathway, in addition to a favorable stability profile in rat plasma, made Chemical II an optimal candidate. Next, six analogues based on the structure of Chemical II were synthesized and evaluated in plasma and liver homogenate. Compared to Chemical II, these compounds generated less active PMEA levels in rat liver homogenate. Therefore, chemical modification of Chemical II may lead to new promising PMEA derivatives with enhanced plasma stability and liver activation. | Gómez-Coca RB, Blindauer CA, Sigel A, Operschall BP, Holý A, Sigel H (2012)
Extent of intramolecular π-stacks in aqueous solution in mixed-ligand copper(II) complexes formed by heteroaromatic amines and several 2-aminopurine derivatives of the antivirally active nucleotide analog 9-[2-(phosphonomethoxy)ethyl]adenine (PMEA).
Chemistry & biodiversity 9, 2008-2034 [PubMed:22976988]
[show Abstract]
The acidity constants of twofold protonated, antivirally active, acyclic nucleoside phosphonates (ANPs), H(2)(PE)(±), where PE(2-)=9-[2-(phosphonomethoxy)ethyl]adenine (PMEA(2-)), 2-amino-9-[2-(phosphonomethoxy)ethyl]purine (PME2AP(2-)), 2,6-diamino-9-[2-(phosphonomethoxy)ethyl]purine (PMEDAP(2-)), or 2-amino-6-(dimethylamino)-9-[2-(phosphonomethoxy)ethyl]purine (PME(2A6DMAP)(2-)), as well as the stability constants of the corresponding ternary Cu(Arm)(H;PE)(+) and Cu(Arm)(PE) complexes, where Arm=2,2'-bipyridine (bpy) or 1,10-phenanthroline (phen), are compared. The constants for the systems containing PE(2-)=PMEDAP(2-) and PME(2A6DMAP)(2-) have been determined now by potentiometric pH titrations in aqueous solution at I=0.1M (NaNO(3)) and 25°; the corresponding results for the other ANPs were taken from our earlier work. The basicity of the terminal phosphonate group is very similar for all the ANP(2-) species, whereas the addition of a second amino substituent at the pyrimidine ring of the purine moiety significantly increases the basicity of the N(1) site. Detailed stability-constant comparisons reveal that, in the monoprotonated ternary Cu(Arm)(H;PE)(+) complexes, the proton is at the phosphonate group, that the ether O-atom of the -CH(2)-O-CH(2)-P(O)(2)(-)(OH) residue participates, next to the P(O)(2)(-)(OH) group, to some extent in Cu(Arm)(2+) coordination, and that π-π stacking between the aromatic rings of Cu(Arm)(2+) and the purine moiety is rather important, especially for the H·PMEDAP(-) and H·PME(2A6DMAP)(-) ligands. There are indications that ternary Cu(Arm)(2+)-bridged stacks as well as unbridged (binary) stacks are formed. The ternary Cu(Arm)(PE) complexes are considerably more stable than the corresponding Cu(Arm)(R-PO(3)) species, where R-PO(3)(2-) represents a phosph(on)ate ligand with a group R that is unable to participate in any kind of intramolecular interaction within the complexes. The observed stability enhancements are mainly attributed to intramolecular-stack formation in the Cu(Arm)(PE) complexes and also, to a smaller extent, to the formation of five-membered chelates involving the ether O-atom present in the -CH(2)-O-CH(2)-PO(3)(2-) residue of the PE(2-) species. The quantitative analysis of the intramolecular equilibria involving three structurally different Cu(Arm)(PE) isomers shows that, e.g., ca. 1.5% of the Cu(phen)(PMEDAP) system exist with Cu(phen)(2+) solely coordinated to the phosphonate group, 4.5% as a five-membered chelate involving the ether O-atom of the -CH(2)-O-CH(2)-PO(3)(2-) residue, and 94% with an intramolecular π-π stack between the purine moiety of PMEDAP(2-) and the aromatic rings of phen. Comparison of the various formation degrees of the species formed reveals that, in the Cu(phen)(PE) complexes, intramolecular-stack formation is more pronounced than in the Cu(bpy)(PE) species. Within a given Cu(Arm)(2+) series the stacking intensity increases in the order PME2AP(2-) | Herreros de Tejada Echanojáuregui A, Moreno Planas JM, Rubio González E, Portero Azorin F, López Monclús J, Revilla Negro J, Lucena de la Poza JL, Sánchez Turrión V, Barrios Peinado C, Cuervas-Mons Martínez V (2005)
Adefovir dipivoxil therapy in liver transplant recipients with lamivudine-resistant hepatitis B virus.
Transplantation proceedings 37, 1507-1508 [PubMed:15866657]
[show Abstract]
Hepatitis B virus (HBV) infection is the leading cause of cirrhosis worldwide. One effective strategy to prevent recurrence or transmission of HBV infection after liver transplantation exists is prescription of Lamivudine, although it is associated with high resistance rates. Adefovir dipivoxil (AD) is a nucleotide analogue of adenosine that has achieved significant results in virologic, biochemical, and clinical parameters in lamivudine-resistant HBV-infected patients. Between 1990 and 2003 7 adult recipients of orthotopic liver transplants who experienced lamivudine-resistant HBV infection (pretransplantation or posttransplantation) were enrolled in a prospective study to administer AD for 48 weeks. At baseline they showed serum HBV DNA between 2.2 x 10(6) and 1.1 x 10(8) copies/mL. After 48 weeks of AD treatment, the median time-weighted average change in serum HBV DNA (log 10 copies/mL) was -3.19 (SD, 1.65). In 3 patients with HBV, DNA was undetectable (<400 copies/mL) at the end of the follow-up. HBe antigen seroconversion was observed in 1 patient. No significant adverse effects were recorded, except for renal functional impairment in 1 patient who had previous renal insufficiency. In our study, adefovir was an effective drug to suppression HBV replication in liver transplant recipients with lamivudine-resistant HBV. Excluding renal function abnormalities, tolerance of the drug was excellent. None of the patients developed resistance to adefovir. Therapy with AD in liver transplant recipients is effective and safe, although renal function should be monitored closely. | Shen Y, Zhukovskaya NL, Zimmer MI, Soelaiman S, Bergson P, Wang CR, Gibbs CS, Tang WJ (2004)
Selective inhibition of anthrax edema factor by adefovir, a drug for chronic hepatitis B virus infection.
Proceedings of the National Academy of Sciences of the United States of America 101, 3242-3247 [PubMed:14978283]
[show Abstract]
Edema factor (EF), a key virulence factor in anthrax pathogenesis, has calmodulin (CaM)-activated adenylyl cyclase activity. We have found that adefovir dipivoxil, a drug approved to treat chronic infection of hepatitis B virus, effectively inhibits EF-induced cAMP accumulation and changes in cytokine production in mouse primary macrophages. Adefovir diphosphate (PMEApp), the active cellular metabolite of adefovir dipivoxil, inhibits the adenylyl cyclase activity of EF in vitro with high affinity (K(i) = 27 nM). A crystal structure of EF-CaM-PMEApp reveals that the catalytic site of EF forms better van der Waals contacts and more hydrogen bonds with PMEApp than with its endogenous substrate, ATP, providing an explanation for the approximately 10,000-fold higher affinity EF-CaM has for PMEApp versus ATP. Adefovir dipivoxil is a clinically approved drug that can block the action of an anthrax toxin. It can be used to address the role of EF in anthrax pathogenesis. | Köck J, Baumert TF, Delaney WE, Blum HE, von Weizsäcker F (2003)
Inhibitory effect of adefovir and lamivudine on the initiation of hepatitis B virus infection in primary tupaia hepatocytes.
Hepatology (Baltimore, Md.) 38, 1410-1418 [PubMed:14647052]
[show Abstract]
Adefovir dipivoxil and lamivudine are two safe and efficacious drugs licensed for the treatment of chronic hepatitis B virus (HBV) infection. Both drugs inhibit the viral polymerase, resulting in a profound suppression of virus production. Blocking the viral polymerase may also affect the initiation of HBV infection, because HBV virions harbor a partially double-stranded genome and productive infection requires completion of viral plus-strand DNA synthesis with subsequent formation of covalently closed circular DNA (cccDNA). To address this issue, we used primary hepatocytes from the tree shrew Tupaia belangeri that were recently shown to be susceptible to HBV infection. Treatment of cells with either drug partially inhibited initial HBV cccDNA formation. Adefovir was more effective than lamivudine, resulting in a 3-fold reduction of RNA synthesis and viral surface antigen production. However, prevention of initial cccDNA formation was incomplete even after combined treatment, whereas de novo synthesis of viral replicative intermediates was completely suppressed. A possible explanation for this observation is the genomic plus-strand gap of less than 200 bases in some virions, limiting the window for antiviral action. In conclusion, nucleos(t)ide analogues can target initial plus-strand DNA repair and reduce but not completely block HBV infection. | Delmas J, Schorr O, Jamard C, Gibbs C, Trépo C, Hantz O, Zoulim F (2002)
Inhibitory effect of adefovir on viral DNA synthesis and covalently closed circular DNA formation in duck hepatitis B virus-infected hepatocytes in vivo and in vitro.
Antimicrobial agents and chemotherapy 46, 425-433 [PubMed:11796353]
[show Abstract]
The elimination of viral covalently closed circular DNA (CCC DNA) from the nucleus of infected hepatocytes is an obstacle to achieving sustained viral clearance during antiviral therapy of chronic hepatitis B virus (HBV) infection. The aim of our study was to determine whether treatment with adefovir, a new acyclic nucleoside phosphonate, the prodrug of which, adefovir dipivoxil, is in clinical evaluation, is able to suppress viral CCC DNA both in vitro and in vivo using the duck HBV (DHBV) model. First, the effect of adefovir on viral CCC DNA synthesis was examined with primary cultures of DHBV-infected fetal hepatocytes. Adefovir was administered for six consecutive days starting one day before or four days after DHBV inoculation. Dose-dependent inhibition of both virion release in culture supernatants and synthesis of intracellular viral DNA was observed. Although CCC DNA amplification was inhibited by adefovir, CCC DNA was not eliminated by antiviral treatment and the de novo formation of CCC DNA was not prevented by pretreatment of the cells. Next, preventive treatment of experimentally infected ducklings with lamivudine or adefovir revealed that both efficiently suppressed viremia and intrahepatic DNA. However, persistence of viral DNA even when detectable only by PCR was associated with a recurrence of viral replication following drug withdrawal. Taken together, our results demonstrate that adefovir is a potent inhibitor of DHBV replication that inhibits CCC DNA amplification but does not effectively prevent the formation of CCC DNA from incoming viral genomes. | Sparidans RW, Veldkamp A, Hoetelmans RM, Beijnen JH (1999)
Improved and simplified liquid chromatographic assay for adefovir, a novel antiviral drug, in human plasma using derivatization with chloroacetaldehyde.
Journal of chromatography. B, Biomedical sciences and applications 736, 115-121 [PubMed:10676990]
[show Abstract]
A rapid and simplified chromatographic assay is reported for the quantification of adefovir (PMEA) utilizing derivatization with chloroacetaldehyde. Adefovir is isolated from plasma using protein precipitation with trichloroacetic acid; next, the fluorescent 1,N6-etheno derivative is directly formed at 98 degrees C in the buffered extract with chloroacetaldehyde. This derivative is analyzed using isocratic ion-pair liquid chromatography and fluorescence detection at 254 nm for excitation and 425 nm for emission. In the evaluated concentration range (10-1000 ng/ml) precisions < or = 5% and accuracies between 95 and 117% were found, using a 0.2-ml volume of plasma. The lower limit of quantification is 10 ng/ml with a intra-assay precision of 16%. The currently reported bioanalytical method is 20-25-fold more sensitive than previously published assays. |
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