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Al-Wahaibi LH, Öztürk N, Hassan HM, Sert Y, El-Emam AA, Al-Tamimi AMS, Gökce H. Experimental (FT-IR, Laser-Raman and NMR) and theoretical comparative study on 2-benzylsulfanyl-4-pentyl-6-(phenylsulfanyl)pyrimidine-5-carbonitrile, a potential bioactive agent. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2018. [DOI: 10.1142/s0219633618500359] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In this paper, the experimental and theoretical vibrational frequencies of a potential bioactive pyrimidine derivative molecule named 2-benzylsulfanyl-4-pentyl-6-(phenylsulfanyl)pyrimidine-5-carbonitrile has been investigated. The experimental FT-IR and Laser-Raman spectra of the studied molecule are in the region (4000–400[Formula: see text]cm[Formula: see text] and (4000–100[Formula: see text]cm[Formula: see text], respectively, in gas phase. The vibrational modes and optimized ideal structure parameters(bond lengths, bond angles and selected dihedral angles) were calculated by using DFT/B3LYP, DFT/BHandHLYP and DFT/PBE1PBE methods with 6-311[Formula: see text]G(d,p) basis set. The theoretical mode assignments have been obtained by using potential energy distribution (PED) with the VEDA4 software program. Additionally, infrared and Raman intensities, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) energies and their clouds, and other related molecular properties were calculated and evaluated. The proton (1H) and carbon-13 ([Formula: see text]C) nuclear magnetic resonance (NMR) chemical shifts have been investigated for the title molecule, both experimentally (in DMSO-d[Formula: see text] and theoretically (in vacuum and DMSO). The thermodynamic properties of the tile compound have been investigated using the mentioned theoretical computational methods. The results revealed that there isgood agreement between experimental and theoretical results and these results have supported the related literature.
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Affiliation(s)
- Lamya H. Al-Wahaibi
- Department of Chemistry, College of Sciences, Princess Nourah Bint Abdulrahman University, Riyadh 11671, Saudi Arabia
| | - Nuri Öztürk
- Dereli Vocational School, Giresun University, 28950 Giresun, Turkey
| | - Hanan M. Hassan
- Department of Pharmacology and Biochemistry, College of Pharmacy, Delta University for Science and Technology, Mansoura, Egypt
| | - Yusuf Sert
- Sorgun Vocational School, Bozok University, 66100 Yozgat, Turkey
| | - Ali A. El-Emam
- Department of Medicinal Chemistry, Faculty of Pharmacy, University of Mansoura, Mansoura 35516, Egypt
| | - Abdul-Malek S. Al-Tamimi
- Department of Pharmaceutical Chemistry, College of Pharmacy, Sattam bin Abdulaziz University, Alkharj 11942, Saudi Arabia
| | - Halil Gökce
- Vocational School of Health Services, Giresun University, 28200 Giresun, Turkey
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Rodríguez M, Pascasio JM, Fraga E, Fuentes J, Prieto M, Sánchez-Antolín G, Calleja JL, Molina E, García-Buey ML, Blanco MÁ, Salmerón J, Bonet ML, Pons JA, González JM, Casado MÁ, Jorquera F. Tenofovir vs lamivudine plus adefovir in chronic hepatitis B: TENOSIMP-B study. World J Gastroenterol 2017; 23:7459-7469. [PMID: 29151700 PMCID: PMC5685852 DOI: 10.3748/wjg.v23.i41.7459] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Revised: 05/22/2017] [Accepted: 06/19/2017] [Indexed: 02/06/2023] Open
Abstract
AIM To demonstrate the non-inferiority (15% non-inferiority limit) of monotherapy with tenofovir disoproxil fumarate (TDF) vs the combination of lamivudine (LAM) plus adefovir dipivoxil (ADV) in the maintenance of virologic response in patients with chronic hepatitis B (CHB) and prior failure with LAM.
METHODS This study was a Phase IV prospective, randomized, open, controlled study with 2 parallel groups (TDF and LAM+ADV) of adult patients with hepatitis B e antigen (HBeAg)-negative CHB, prior failure with LAM, on treatment with LAM+ADV for at least 6 mo, without prior resistance to ADV and with an undetectable viral load at the start of the study, in 14 Spanish hospitals. The follow-up time for each patient was 48 wk after randomization, with quarterly visits in which the viral load, biochemical and serological parameters, adverse effects, adherence to treatment and consumption of hospital resources were analysed.
RESULTS Forty-six patients were evaluated [median age: 55.4 years (30.2-75.2); 84.8% male], including 22 patients with TDF and 24 with LAM+ADV. During study development, hepatitis B virus DNA (HBV-DNA) remained undetectable, all patients remained HBeAg negative, and hepatitis B surface antigen (HBsAg) positive. Alanine aminotransferase (ALT) values at the end of the study were similar in the 2 groups (25.1 ± 7.65, TDF vs 24.22 ± 8.38, LAM+ADV, P = 0.646). No significant changes were observed in creatinine or serum phosphorus values in either group. No significant differences between the 2 groups were noted in the identification of adverse effects (AEs) (53.8%, TDF vs 37.5%, LAM+ADV, P = 0.170), and none of the AEs which occurred were serious. Treatment adherence was 95.5% and 83.3% in the TDF and the LAM+ADV groups, respectively (P = 0.488). The costs associated with hospital resource consumption were significantly lower with the TDF treatment than the LAM+ADV treatment (€4943 ± 1059 vs €5811 ± 1538, respectively, P < 0.001).
CONCLUSION TDF monotherapy proved to be safe and not inferior to the LAM+ADV combination therapy in maintaining virologic response in patients with CHB and previous LAM failure. In addition, the use of TDF generated a significant savings in hospital costs.
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Affiliation(s)
- Manuel Rodríguez
- Division of Gastroenterology and Hepatology. Hospital Universitario Central de Asturias, Oviedo 33011, Spain
| | - Juan Manuel Pascasio
- Unit for the Clinical Management of Digestive Diseases, IBIS, Hospital Universitario Virgen del Rocío, Sevilla 41013, Spain and CIBERehd
| | - Enrique Fraga
- Liver Transplantation and Hepatology Unit, Gastroenterology Service, Hospital Universitario Reina Sofía, Córdoba 14004, Spain
| | - Javier Fuentes
- Digestive Medicine Service, Hospital Universitario Miguel Servet, Zaragoza 50009, Spain
| | - Martín Prieto
- Hepatology Unit, Digestive Medicine Service, Hospital Universitari i Politècnic La Fe, Valencia 46026, Spain and CIBERehd
| | | | - José Luis Calleja
- Liver Unit, Hospital Universitario Puerta de Hierro de Majadahonda, Universidad Autónoma de Madrid, Madrid 28049, Spain
| | - Esther Molina
- Digestive Medicine Service, Hospital Clínico de Santiago de Compostela, La Coruña 15706, Spain
| | | | - María Ángeles Blanco
- Digestive Medicine Service, Hospital General Universitario Gregorio Marañón, Madrid 28007, España
| | - Javier Salmerón
- Digestive Medicine Unit, Complejo Hospitalario de Granada, Granada 18014, Spain
| | - María Lucía Bonet
- Digestive Medicine Service, Hospital Universitario Son Espases, Palma de Mallorca 07120, Spain
| | - José Antonio Pons
- Hepatology Unit, IMIB Hospital Universitario Virgen de la Arrixaca, Murcia 30120, Spain
| | - José Manuel González
- Digestive Medicine Service, Hospital Clínico Universitario de Valladolid, Valladolid 47003, Spain
| | | | - Francisco Jorquera
- Division of Gastroenterology and Hepatology, Complejo Asistencial Universitario de León, León 24001, Spain CIBERehd and IBIOMED León
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Yamada N, Sugiyama R, Nitta S, Murayama A, Kobayashi M, Okuse C, Suzuki M, Yasuda K, Yotsuyanagi H, Moriya K, Koike K, Wakita T, Kato T. Resistance mutations of hepatitis B virus in entecavir-refractory patients. Hepatol Commun 2017; 1:110-121. [PMID: 29404449 PMCID: PMC5721430 DOI: 10.1002/hep4.1022] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 12/28/2016] [Accepted: 02/08/2017] [Indexed: 12/17/2022] Open
Abstract
The emergence of resistance mutations in the reverse transcriptase gene of hepatitis B virus (HBV) is associated with treatment failure. Entecavir (ETV) is one of the most potent anti‐HBV reagents; it has a very low resistance rate and is used as the first‐line treatment for chronic hepatitis B. In this study, we isolated HBVs in 4 ETV‐refractory patients (2 with viral breakthrough, 1 with partial virological response, and 1 with flare‐up) and assessed ETV resistance using replication‐competent 1.38‐fold HBV genome‐length molecular clones. The full genome sequences of infected HBVs in ETV‐refractory patients were determined. The HBV molecular clones were generated with the patient‐derived sequences. After transfection of these molecular clones into HepG2 cells, viral replications and ETV susceptibilities were evaluated by measuring the amount of intracellular core‐particle‐associated HBV DNA using Southern blotting and real‐time polymerase chain reaction. Among these cases, ETV‐resistant variants were detected in 2 patients with viral breakthrough and responsible amino acid mutations in reverse transcriptase were successfully identified in these variants. No ETV‐resistant mutation was detected in the other cases. The identified ETV‐resistant mutations did not confer resistance to tenofovir disoproxil fumarate. Conclusion: The HBV replication model with patient‐derived sequences is useful for assessing replication efficiency, susceptibility to anti‐HBV reagents, and responsible resistance mutations and can aid in choosing the appropriate treatment strategy for treatment‐failure cases of chronic hepatitis B. (Hepatology Communications 2017;1:110‐121)
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Affiliation(s)
- Norie Yamada
- Department of Virology II National Institute of Infectious Diseases Tokyo Japan.,Department of Internal Medicine Center for Liver Diseases, Seizankai Kiyokawa Hospital Tokyo Japan
| | - Ryuichi Sugiyama
- Department of Virology II National Institute of Infectious Diseases Tokyo Japan
| | - Sayuri Nitta
- Department of Virology II National Institute of Infectious Diseases Tokyo Japan.,Department of Gastroenterology and Hepatology Tokyo Medical and Dental University Tokyo Japan
| | - Asako Murayama
- Department of Virology II National Institute of Infectious Diseases Tokyo Japan
| | - Minoru Kobayashi
- Department of Internal Medicine Center for Liver Diseases, Seizankai Kiyokawa Hospital Tokyo Japan
| | - Chiaki Okuse
- Department of Internal Medicine Division of Gastroenterology and Hepatology, St. Marianna University School of Medicine Kanagawa Japan
| | - Michihiro Suzuki
- Department of Internal Medicine Division of Gastroenterology and Hepatology, St. Marianna University School of Medicine Kanagawa Japan
| | - Kiyomi Yasuda
- Department of Internal Medicine Center for Liver Diseases, Seizankai Kiyokawa Hospital Tokyo Japan
| | - Hiroshi Yotsuyanagi
- Division of Infectious Diseases Advanced Clinical Research Center, Institute of Medical Science
| | - Kyoji Moriya
- Department of Infection Control and Prevention Graduate School of Medicine
| | - Kazuhiko Koike
- Department of Gastroenterology Graduate School of Medicine, The University of Tokyo Tokyo Japan
| | - Takaji Wakita
- Department of Virology II National Institute of Infectious Diseases Tokyo Japan
| | - Takanobu Kato
- Department of Virology II National Institute of Infectious Diseases Tokyo Japan
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Spectroscopic and electronic structure calculation of a potential chemotherapeutic agent 5-propyl-6-(p-tolylsulfanyl)pyrimidine-2,4(1H,3H)-dione using first principles. J Mol Struct 2015. [DOI: 10.1016/j.molstruc.2015.07.042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Baran B, Soyer OM, Ormeci AC, Gokturk S, Evirgen S, Akyuz F, Karaca C, Demir K, Besisik F, Onel D, Gulluoglu M, Badur S, Kaymakoglu S. Tenofovir disoproxil fumarate has a substantial efficacy against multidrug-resistant strains of hepatitis B virus. Liver Int 2015; 35:2265-74. [PMID: 25800974 DOI: 10.1111/liv.12831] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 03/16/2015] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS To evaluate the efficacy of tenofovir in chronic hepatitis B (CHB) patients with adefovir resistance (ADF-R) and suboptimal response to adefovir (ADF-S). METHODS Nucleos(t)ide analogue (NA)-naïve patients and patients with previous adefovir failure receiving tenofovir therapy for at least 6 months were included in the study. Biochemical and virological tests were obtained at baseline and 3-month intervals in the first year and every 6 months thereafter. The primary outcome measure was complete virological response (CVR) (HBVDNA < 20 IU/ml). CVR rates were calculated by Kaplan-Meier analysis, and a multivariate Cox proportional hazard model was generated to find out factors independently associated with CVR. RESULTS A total of 165 patients (118 men, mean age 42 ± 12, 64 HBeAg(+) ) were included in the study. There were 105 patients in NA-naïve, 32 patients in ADF-S and 28 patients in ADF-R groups. All patients in the ADF-R group had multidrug resistance patterns. Mean duration of tenofovir treatment was 29 ± 14 months. CVR rates in NA-naïve, ADF-S and ADF-R groups were 65% vs. 75% vs. 58% at 12th month, 77% vs. 87% vs. 79% at 24th month and 83% vs. 94% vs. 79% at 36th month respectively. According to multivariate Cox regression model, HBeAg positivity (HR = 0.56, 95%CI 0.36-0.86, P = 0.008), high baseline HBVDNA level (HR = 0.64, 95%CI 0.55-0.74, P < 0.001) and ADF-R (HR = 0.47, 95%CI 0.28-0.81, P = 0.006) were independent predictors for CVR. Seven patients encountered mild renal dysfunction and were managed by dose adjustments. CONCLUSION CVR rates during the follow-up show that tenofovir has a decreased, yet still potent in vivo efficacy against multidrug-resistant strains of HBV.
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Affiliation(s)
- Bulent Baran
- Department of Gastroenterology, Koç University Hospital, Zeytinburnu, Istanbul, Turkey
| | - Ozlem Mutluay Soyer
- Department of Gastroenterohepatology, Istanbul Faculty of Medicine, Istanbul University, Capa, Istanbul, Turkey
| | - Asli Cifcibasi Ormeci
- Department of Gastroenterohepatology, Istanbul Faculty of Medicine, Istanbul University, Capa, Istanbul, Turkey
| | - Suut Gokturk
- Department of Gastroenterohepatology, Istanbul Faculty of Medicine, Istanbul University, Capa, Istanbul, Turkey
| | - Sami Evirgen
- Department of Gastroenterohepatology, Istanbul Faculty of Medicine, Istanbul University, Capa, Istanbul, Turkey
| | - Filiz Akyuz
- Department of Gastroenterohepatology, Istanbul Faculty of Medicine, Istanbul University, Capa, Istanbul, Turkey
| | - Cetin Karaca
- Department of Gastroenterohepatology, Istanbul Faculty of Medicine, Istanbul University, Capa, Istanbul, Turkey
| | - Kadir Demir
- Department of Gastroenterohepatology, Istanbul Faculty of Medicine, Istanbul University, Capa, Istanbul, Turkey
| | - Fatih Besisik
- Department of Gastroenterohepatology, Istanbul Faculty of Medicine, Istanbul University, Capa, Istanbul, Turkey
| | - Derya Onel
- Department of Microbiology, Istanbul Faculty of Medicine, Istanbul University, Capa, Istanbul, Turkey
| | - Mine Gulluoglu
- Department of Pathology, Istanbul Faculty of Medicine, Istanbul University, Capa, Istanbul, Turkey
| | - Selim Badur
- Department of Microbiology, Istanbul Faculty of Medicine, Istanbul University, Capa, Istanbul, Turkey
| | - Sabahattin Kaymakoglu
- Department of Gastroenterohepatology, Istanbul Faculty of Medicine, Istanbul University, Capa, Istanbul, Turkey
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Hayashi S, Murakami S, Omagari K, Matsui T, Iio E, Isogawa M, Watanabe T, Karino Y, Tanaka Y. Characterization of novel entecavir resistance mutations. J Hepatol 2015; 63:546-53. [PMID: 25817219 DOI: 10.1016/j.jhep.2015.03.020] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 03/11/2015] [Accepted: 03/13/2015] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Entecavir (ETV) is approved for the treatment of chronic hepatitis B virus (HBV) infections, but the virus can acquire resistance to the drug. This requires lamivudine resistance mutations (LAMr) and at least one additional mutation. Here, we characterized two novel mutations, rtI163V and rtA186T, associated with viral breakthrough (VBT) in an ETV-refractory patient. METHODS HBV from an ETV-refractory patient was sequenced, and newly identified mutations were inserted into a replication-competent clone by mutagenesis. Clones were analyzed for replication efficacy and susceptibility to ETV in vitro. Chimeric mice with human hepatocytes were inoculated with the patient's serum at VBT, and monitored for viral mutation pattern using a next-generation sequencing approach. RESULTS RtI163V and rtA186T mutations were detected together with LAMr (rtL180M and rtM204V) at VBT. RtA186T plus LAMr reduced susceptibility to ETV more than 111.1-fold compared with the wild-type clone, while rtI163V plus LAMr resulted in a 20.4-fold reduction. RtA186T significantly reduced viral replication efficacy, while the rtI163V mutation rescued it. Interestingly, the viral mutation pattern in the chimeric mice indicated dominant (or selective) proliferation of a clone containing rtI163V and rtA186T mutations plus LAMr under ETV treatment. Three-dimensional docking simulation indicated that rtA186T reduced the binding affinity of the HBV polymerase to ETV. CONCLUSIONS VBT in this ETV-refractory patient is attributable to the novel ETV resistance mutations rtI163V and rtA186T. RtA186T was apparently responsible for ETV resistance but the selection of a clone with the double mutation plus LAMr suggests that rtI163V is required to sustain viral fitness.
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Affiliation(s)
- Sanae Hayashi
- Department of Virology & Liver Unit, Nagoya City University Graduate School of Medical Science, Nagoya, Japan
| | - Shuko Murakami
- Department of Virology & Liver Unit, Nagoya City University Graduate School of Medical Science, Nagoya, Japan
| | - Katsumi Omagari
- Department of Virology & Liver Unit, Nagoya City University Graduate School of Medical Science, Nagoya, Japan
| | - Takeshi Matsui
- Department of Virology & Liver Unit, Nagoya City University Graduate School of Medical Science, Nagoya, Japan; Center for Gastroenterology, Teine Keijinkai Hospital, Sapporo, Japan
| | - Etsuko Iio
- Department of Virology & Liver Unit, Nagoya City University Graduate School of Medical Science, Nagoya, Japan
| | - Masanori Isogawa
- Department of Virology & Liver Unit, Nagoya City University Graduate School of Medical Science, Nagoya, Japan
| | - Tsunamasa Watanabe
- Department of Virology & Liver Unit, Nagoya City University Graduate School of Medical Science, Nagoya, Japan
| | - Yoshiyasu Karino
- Department of Gastroenterology, Sapporo Kosei General Hospital, Hokkaido, Japan
| | - Yasuhito Tanaka
- Department of Virology & Liver Unit, Nagoya City University Graduate School of Medical Science, Nagoya, Japan.
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Wang J, Liu J, Qi C, Yan T, Cao F, Jin L, He Y, Yang Y, Zhang S, Chen T, Zhao Y. Efficacy of tenofovir disoproxil fumarate to prevent vertical transmission in mothers with lamivudine-resistant HBV. Antivir Ther 2015. [PMID: 26215771 DOI: 10.3851/imp2981] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND In China, women with chronic HBV infection and who are of childbearing age receive lamivudine at an early age. Thus, viral resistance becomes a challenge for intervention to prevent mother-to-infant transmission. We prospectively assessed the efficacy of tenofovir in pregnant women with lamivudine-resistant HBV. METHODS Chronic HBV-infected mothers resistant to lamivudine were enrolled. Tenofovir was administrated at gestation weeks 24 or 28. Virological and biochemical parameters were assessed. All infants received combined immunoprophylaxis and were followed for 1 year. RESULTS Of the 48 mothers enrolled, 21 started tenofovir therapy at gestation week 24 and 27 started at week 28. Tenofovir resulted in an HBV DNA decline of 5.23 ± 1.68 log10 IU/ml at delivery. The group starting therapy at week 24 exhibited a more rapid viral inhibition (P<0.001) and more significant HBV DNA load decline (5.89 ± 1.66 versus 4.72 ± 1.55; P=0.019) than the group starting at week 28. At delivery, all mothers had a viral titre <10(6) IU/ml, 76.2% from the week 24 starting group displayed virus <10(4) IU/ml, and 52.4% showed undetectable virus at delivery, much higher than the week 28 starting group (29.6%), although there was no statistically significant difference in viral levels at delivery between the two groups. Congenital abnormalities and neonatal growth were comparable to the normal population. No case of perinatal transmission was diagnosed. CONCLUSIONS This investigation clarifies the efficacy of tenofovir for reducing vertical transmission of HBV in mothers with lamivudine-resistant HBV and demonstrates that tenofovir is well-tolerated in the second and third trimesters.
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Affiliation(s)
- Jing Wang
- Department of Infectious Disease, the First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, China
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Vibrational spectroscopic and molecular docking study of 2-Benzylsulfanyl-4-[(4-methylphenyl)-sulfanyl]-6-pentylpyrimidine-5-carbonitrile, a potential chemotherapeutic agent. SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 137:569-80. [PMID: 25240829 DOI: 10.1016/j.saa.2014.08.112] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 08/06/2014] [Accepted: 08/24/2014] [Indexed: 11/24/2022]
Abstract
FT-IR and FT-Raman spectra of 2-Benzylsulfanyl-4-[(4-methylphenyl)-sulfanyl]-6-pentylpyrimidine-5-carbonitrile were recorded and analyzed. The structure of the molecule has been optimized and the structural characteristics have been determined by density functional theory. The geometrical parameters (DFT) are in agreement with the XRD results. HOMO and LUMO and other chemical properties are reported. Nonlinear optical properties are reported. A detailed molecular picture of the title compound and its interactions were obtained from NBO analysis. The negative (red and yellow) regions of the MEP are related to electrophilic reactivity and the positive (blue) regions to nucleophilic reactivity, as shown in the MEP plot and the title compound has several possible sites, CN, N atom of pyrimidine ring and sulfur atoms for electrophilic attack. From the molecular docking studies it is clear that the title compound binds at the catalytic site of the substrate by weak non-covalent interactions most prominent of which are H-bonding, π-π, alkyl-π, and amide-π interactions.
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Hou JL, Gao ZL, Xie Q, Zhang JM, Sheng JF, Cheng J, Chen CW, Mao Q, Zhao W, Ren H, Tan DM, Niu JQ, Chen SJ, Pan C, Tang H, Wang H, Mao YM, Jia JD, Ning Q, Xu M, Wu SM, Li J, Zhang XX, Ji Y, Dong J, Li J. Tenofovir disoproxil fumarate vs adefovir dipivoxil in Chinese patients with chronic hepatitis B after 48 weeks: a randomized controlled trial. J Viral Hepat 2015; 22:85-93. [PMID: 25243325 DOI: 10.1111/jvh.12313] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Tenofovir disoproxil fumarate (TDF) has demonstrated long-term efficacy and a high barrier to resistance in multiple chronic hepatitis B (CHB) populations outside of China. This study aimed to evaluate the efficacy and safety of TDF compared with adefovir dipivoxil (ADV) in Chinese patients with CHB during 48 weeks of treatment (ClinicalTrial.gov number, NCT01300234). A Phase 3, multicentred, randomized, double-blind, controlled trial compared the efficacy and safety of TDF with ADV in Chinese patients with CHB. The primary endpoint was the proportion of patients with HBV DNA <400 copies/mL in each treatment group at Week 48, using an unpooled Z-test for superiority. Secondary endpoints included viral suppression, serologic response, histological improvement, normalization of alanine aminotransferase (ALT) levels and the emergence of resistance mutations. A total of 509 patients, 202 hepatitis B e antigen (HBeAg)-positive and 307 HBeAg-negative, with HBV DNA ≥10(5) copies/mL received either TDF 300 mg od or ADV 10 mg od. At Week 48, TDF demonstrated superior viral suppression compared with ADV in both HBeAg-positive (76.7% vs 18.2%, P < 0.0001) and HBeAg-negative (96.8% vs 71.2%, P < 0.0001) patients. The majority of patients in both treatment arms achieved ALT normalization (>85%). No resistance to TDF was observed. The frequency of adverse events was comparable between treatment arms (TDF 3.9% vs ADV 4.8%). In this double-blind, randomized, clinical trial, TDF demonstrated superiority over ADV with respect to viral suppression in Chinese patients with CHB at 48 weeks of treatment and without the development of resistance.
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Affiliation(s)
- J L Hou
- Department of Infectious Diseases and Hepatology Unit, Nanfang Hospital, Guangzhou, China
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10
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Zhou YJ, Lv J, Yu K, Ma JP, Guo DS. Supramolecular structures in three thiouracil derivatives: 5,6-trimethylene-2-sulfanylidene-1,2-dihydropyrimidin-4(3H)-one, 2-(4-fluorobenzylsulfanyl)-5,6-trimethylenepyrimidin-4(3H)-one and methyl 2-{[2-(4-fluorobenzylsulfanyl)-5,6-trimethylenepyrimidin-4-yl]oxy}acetate. ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY 2014; 70:416-20. [PMID: 24705060 DOI: 10.1107/s2053229614006111] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 03/19/2014] [Indexed: 11/10/2022]
Abstract
The molecules of the title compounds, C7H8N2OS, (1), C14H13FN2OS, (2), and C17H17FN2O3S, (3), crystallize in the space groups C2/m, C2/c and Ia, respectively. Compounds (1) and (2), an S-alkylated derivative of (1), consist of only one symmetry-independent molecule, while (3), an O-alkylated derivative of (2), contains two independent molecules in the asymmetric unit. The molecules of (1) sit on crystallographic mirror planes. In the supramolecular structure of (1), a combination of N-H···O and N-H···S hydrogen bonds creates a molecular strap with C(6) and R2(2)(8) motifs, which is further stabilized by an S···S contact. In the packing of (2), a one-dimensional molecular column is made up of two kinds of dimers. One dimer, with an R2(2)(18) motif, is formed by a pair of C-H···O soft hydrogen bonds and the other, with an R2(2)(8) motif, is produced via a pair of N-H···O hard hydrogen bonds. In the packing of (3), molecules A and B form two different types of one-dimensional chain by intermolecular C-H···N hydrogen bonds, and by C···N and O···S contacts, respectively. Two such kinds of chain are connected alternately via interchain C-H···O hydrogen bonds, giving a two-dimensional sheet. Finally, a three-dimensional supramolecular structure is formed through weak intersheet C-H···F hydrogen bonds. The study of the molecular and supramolecular structures of thiouracil derivatives is significant in the development of lipoprotein-associated phospholipase A2 inhibitors.
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Affiliation(s)
- Yu-Jun Zhou
- Department of Chemistry, Shandong Normal University, Jinan 250014, People's Republic of China
| | - Jing Lv
- Department of Chemistry, Shandong Normal University, Jinan 250014, People's Republic of China
| | - Kai Yu
- Department of Chemistry, Shandong Normal University, Jinan 250014, People's Republic of China
| | - Jian-Ping Ma
- Department of Chemistry, Shandong Normal University, Jinan 250014, People's Republic of China
| | - Dian-Shun Guo
- Department of Chemistry, Shandong Normal University, Jinan 250014, People's Republic of China
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Si Ahmed SN, Zoulim F. Pathobiology of HBV mutants and clinical impact for treatment monitoring. Expert Rev Anti Infect Ther 2014; 7:309-20. [DOI: 10.1586/eri.09.10] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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12
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Hu CY, Liu YM, Liu Y, Chen Q, Wang W, Wu K, Dong J, Li J, Jia JY, Lu C, Sun SX, Yu C, Li X. Pharmacokinetics and Tolerability of Tenofovir Disoproxil Fumarate 300 mg Once Daily: An Open-Label, Single- and Multiple-Dose Study in Healthy Chinese Subjects. Clin Ther 2013; 35:1884-9. [DOI: 10.1016/j.clinthera.2013.09.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 09/09/2013] [Accepted: 09/24/2013] [Indexed: 11/27/2022]
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Efficacy of tenofovir in patients with Lamivudine failure is not different from that in nucleoside/nucleotide analogue-naive patients with chronic hepatitis B. Antimicrob Agents Chemother 2013; 57:1790-6. [PMID: 23380725 DOI: 10.1128/aac.02600-12] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
We evaluated the efficacy of tenofovir disoproxil fumarate (TDF) in patients with lamivudine failure (LAM-F) in comparison with that in nucleoside/nucleotide analogue (NA)-naïve patients with chronic hepatitis B (CHB). The criteria for inclusion were being NA naïve or having previous LAM-F and receiving TDF therapy for at least 6 months. Biochemical and virological tests were performed at the baseline, at 3-month intervals in the first year, and every 6 months thereafter. The primary outcome measure for efficacy was a complete virological response (CVR), defined as an HBV DNA level of <20 IU/ml. CVR rates were calculated by Kaplan-Meier analysis, and a multivariate Cox proportional-hazard model was generated in order to find predictive factors independently associated with the time to a CVR. We included 197 patients in the study (136 males; mean age, 43 ± 12 years; 105 patients were NA naïve). Sixty-five patients had hepatitis B e antigen (HBeAg)-positive CHB. The median duration of TDF treatment was 29 (range, 6 to 52) months. Seventy-one patients (77%) in the LAM-F group were treated with TDF add-on therapy. The CVR rates of the NA-naïve and LAM-F groups were comparable in HBeAg-negative (94% versus 96% at month 36, P = 0.10) and HBeAg-positive patients (67% versus 83% at month 36, P = 0.48). According to the multivariate Cox regression model, only HBeAg positivity (hazard ratio [HR], 0.39; 95% confidence interval [CI], 0.26 to 0.59; P < 0.001) and a high baseline HBV DNA level (HR, 0.44; 95% CI, 0.29 to 0.67; P < 0.001) had a significant influence on the time to a CVR. The similar cumulative CVR rates during the follow-up show that TDF has comparable efficacy in lamivudine-experienced and NA-naïve patients, and the presence of resistance mutations did not alter the response rates.
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El-Emam AA, Al-Deeb OA, El-Brollosy NR, Ng SW, Tiekink ERT. 2-[(4-Chloro-benz-yl)sulfanyl]-4-(2-methyl-prop-yl)-6-[3-(trifluoro-meth-yl)anilino]-pyrimidine-5-carbonitrile. Acta Crystallogr Sect E Struct Rep Online 2012; 68:o2059-60. [PMID: 22807881 PMCID: PMC3393324 DOI: 10.1107/s1600536812025895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Accepted: 06/07/2012] [Indexed: 11/26/2022]
Abstract
Three independent mol-ecules comprise the asymmetric unit of the title compound, C(23)H(20)ClF(3)N(4)S. The conformations of the mol-ecules are similar with the chloro-benzene and CF(3)-benzene rings almost perpendicular to, and almost co-planar with, the pyrimidinyl ring [range of dihedral angles = 80.36 (13)-88.07 (14) and 11.89 (14)-23.30 (14)°, respectively]; the benzene rings are roughly orthogonal to each other [64.81 (16)-72.16 (15)°]. In the crystal, two of the independent mol-ecules associate via weak N-H⋯N(cyano) hydrogen bonds and 12-membered {⋯HNC(3)N}(2) synthons; the third independent mol-ecule self-associates similarly but about a centre of inversion. The sample studied was found to be a non-merohedral twin and the minor twin component refined to 47.16 (7)%.
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El-Emam AA, Al-Deeb OA, Al-Turkistani AA, Ng SW, Tiekink ERT. 2-[(4-Chloro-benz-yl)sulfan-yl]-4-(2-methyl-prop-yl)-6-(phenyl-sulfan-yl)pyrimidine-5-carbonitrile. Acta Crystallogr Sect E Struct Rep Online 2012; 68:o2055-6. [PMID: 22807879 PMCID: PMC3393322 DOI: 10.1107/s1600536812025810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Accepted: 06/06/2012] [Indexed: 11/06/2023]
Abstract
In the title compound, C(22)H(20)ClN(3)S(2), the S-bound benzene rings are inclined [dihedral angles = 78.13 (10) and 36.70 (9)°] with respect to the pyrimidine ring. The methyl-propyl group occupies a position normal to the pyrimidine ring [N-C-C-C torsion angle = 92.3 (2)°]. In the crystal, supra-molecular layers are formed in the bc plane, being consolidated by C-H⋯π and π-π inter-actions, the latter between the pyrimidine and S-bound benzene rings [inter-centroid distance = 3.7683 (12) Å].
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16
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Al-Deeb OA, El-Emam AA, Al-Turkistani AA, Ng SW, Tiekink ERT. 6-(2-Methyl-prop-yl)-4-oxo-2-sulfanyl-idene-1,2,3,4-tetra-hydro-pyrimidine-5-carbonitrile. Acta Crystallogr Sect E Struct Rep Online 2012; 68:o676-7. [PMID: 22412573 PMCID: PMC3295462 DOI: 10.1107/s1600536812005119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2012] [Accepted: 02/06/2012] [Indexed: 11/11/2022]
Abstract
The title thio-uracil derivative, C(9)H(11)N(3)OS, exists in the thione form. The six atoms comprising the ring are almost coplanar [r.m.s. deviation = 0.015 Å] and the 2-methyl-propyl group lies approximately perpendicular to this plane [the N-C-C-C torsion angle is 72.88 (14)°]. Linear supra-molecular chains along [001] sustained by N-H⋯O and N-H⋯S hydrogen bonding feature in the crystal packing.
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Affiliation(s)
- Omar A. Al-Deeb
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Ali A. El-Emam
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | | | - Seik Weng Ng
- Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
- Chemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203 Jeddah, Saudi Arabia
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Zhou YB, Wang YF, Zhang Y, Zheng LY, Yang XA, Wang N, Jiang JH, Ma F, Yin DT, Sun CY, Wang QD. In vitro activity of cepharanthine hydrochloride against clinical wild-type and lamivudine-resistant hepatitis B virus isolates. Eur J Pharmacol 2012; 683:10-5. [PMID: 22387093 PMCID: PMC7094493 DOI: 10.1016/j.ejphar.2012.02.030] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2011] [Revised: 12/26/2011] [Accepted: 02/14/2012] [Indexed: 12/22/2022]
Abstract
Hepatitis B virus (HBV) infection causes major public health problems worldwide. The clinical limitation of current antiviral drugs for HBV, such as lamivudine, is the emergence of drug-resistant viral strains during prolonged antiviral therapy. Cepharanthine hydrochloride (CH), a natural alkaloid-derived compound, has been reported to possess potent activity against various viruses. The present study was performed to evaluate the in vitro activity of CH against clinical wild-type and lamivudine-resistant HBV isolates in transiently transfected cells. HBV DNA was extracted from serum samples collected both before lamivudine therapy and at the time of viral breakthrough and was amplified by polymerase chain reaction (PCR). The amplicons were cloned into a novel expression vector, pHY106, which can initiate the intracellular HBV replication cycle after cell transfection. Following transfection of the cloned amplicon into HepG2 cells, a drug susceptibility assay was performed. The level of viral antigen, HBeAg, was determined by enzyme-linked immunosorbent assay (ELISA). Quantitative real-time PCR (Q-PCR) was used for determining the amount of intracellular HBV DNA. Heat stress cognate 70 (Hsc70), a host protein required for HBV replication, was also analyzed by reverse transcription PCR (RT-PCR) to explore the possible antiviral mechanism of CH. The results showed that CH inhibited replication and HBeAg production by either wild-type or lamivudine-resistant HBV clinical isolates in a dose-dependent manner. The Hsc70 mRNA was also downregulated significantly. In conclusion, CH is active against both wild-type and lamivudine-resistant HBV clinical isolates, and its activity may be associated with its inhibition of host Hsc70.
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Affiliation(s)
- Yu-Bing Zhou
- Henan Key Laboratory for Pharmacology of Liver Diseases, Academy of Medical and Pharmaceutical Sciences, Zhengzhou University, 40 Daxue Road, Zhengzhou 450052, China
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Zhou Y, Zhang Y, Yang X, Zhao J, Zheng L, Sun C, Jiang J, Yang Q, Wang Q, Chang J. Novel nucleoside analogue FNC is effective against both wild-type and lamivudine-resistant hepatitis B virus clinical isolates. Antivir Ther 2012; 17:1593-9. [DOI: 10.3851/imp2292] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/14/2012] [Indexed: 10/28/2022]
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19
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Liu Y, Wang C, Zhong Y, Li X, Dai J, Ren X, Xu Z, Li L, Yao Z, Ji D, Wang L, Zhang L, Wong VW‐S, Zoulim F, Xu D. Genotypic resistance profile of hepatitis B virus (HBV) in a large cohort of nucleos(t)ide analogue-experienced Chinese patients with chronic HBV infection. J Viral Hepat 2011; 18:e29-39. [PMID: 21392168 PMCID: PMC7167191 DOI: 10.1111/j.1365-2893.2010.01360.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The study investigated the hepatitis B virus (HBV) genotypic resistance profile in 1803 nucleos(t)ide analogue (NA)-experienced Chinese patients with chronic HBV infection. Serum HBV DNA was extracted, and the reverse transcriptase region was analysed by a high-sensitive direct PCR sequencing and verified by clonal sequencing if necessary. Drug-resistant mutations were detected in 560 of the 1803 patients, including 214 of 490 patients who received lamivudine (LAM), 35 of 428 patients who received adefovir (ADV), five of 18 patients who received telbivudine and 306 of 794 patients who received various sequential/combined NA therapies. ADV-resistant mutations were detected in 36 of 381 patients who received LAM and then switched-to ADV in contrast to one of 82 patients who received ADV add-on LAM. Entecavir (ETV)-resistant mutations were detected not only in LAM- and ETV-treated patients but also in LAM-treated ETV-naïve patients. Double mutations rtM204I and rtL180M were detected more frequently in genotype C than in genotype B virus, and patients infected with this mutant had higher alanine transaminase levels than those infected with mutant containing the rtM204I substitution alone. Multidrug-resistant HBV strains were identified in eight patients, including two novel strains with mutational patterns rtL180M + A181V + S202G + M204V + N236T and rtL180M + S202G + M204V + N236T. The results provide new information on HBV genotypic resistance profiles in a large cohort of Chinese patients with chronic HBV infection and may have important clinical implication for HBV drug resistance management in China.
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Affiliation(s)
- Y. Liu
- Viral Hepatitis Research Laboratory, Institute of Infectious Diseases, Beijing 302 Hospital, Beijing, China
| | - C. Wang
- Viral Hepatitis Research Laboratory, Institute of Infectious Diseases, Beijing 302 Hospital, Beijing, China
| | - Y. Zhong
- Viral Hepatitis Research Laboratory, Institute of Infectious Diseases, Beijing 302 Hospital, Beijing, China
| | - X. Li
- Viral Hepatitis Research Laboratory, Institute of Infectious Diseases, Beijing 302 Hospital, Beijing, China
| | - J. Dai
- Viral Hepatitis Research Laboratory, Institute of Infectious Diseases, Beijing 302 Hospital, Beijing, China
| | - X. Ren
- Viral Hepatitis Research Laboratory, Institute of Infectious Diseases, Beijing 302 Hospital, Beijing, China
| | - Z. Xu
- Viral Hepatitis Research Laboratory, Institute of Infectious Diseases, Beijing 302 Hospital, Beijing, China
| | - L. Li
- Viral Hepatitis Research Laboratory, Institute of Infectious Diseases, Beijing 302 Hospital, Beijing, China
| | - Z. Yao
- Viral Hepatitis Research Laboratory, Institute of Infectious Diseases, Beijing 302 Hospital, Beijing, China
| | - D. Ji
- Viral Hepatitis Research Laboratory, Institute of Infectious Diseases, Beijing 302 Hospital, Beijing, China
| | - L. Wang
- Viral Hepatitis Research Laboratory, Institute of Infectious Diseases, Beijing 302 Hospital, Beijing, China
| | - L. Zhang
- Viral Hepatitis Research Laboratory, Institute of Infectious Diseases, Beijing 302 Hospital, Beijing, China
| | - V. W. ‐S. Wong
- Department of Medicine and Therapeutics and Institute of Digestive Disease, The Chinese University of Hong Kong, Hong Kong, China
| | - F. Zoulim
- INSERM, U871, Lyon, France,Université Lyon 1, IFR62 Lyon‐Est, Lyon, France,Hospices Civils de Lyon, Hôtel Dieu, Department of Hepatology and Gastroenterology, Lyon, France
| | - D. Xu
- Viral Hepatitis Research Laboratory, Institute of Infectious Diseases, Beijing 302 Hospital, Beijing, China
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20
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Grimm D, Thimme R, Blum HE. HBV life cycle and novel drug targets. Hepatol Int 2011; 5:644-53. [PMID: 21484123 DOI: 10.1007/s12072-011-9261-3] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Accepted: 02/04/2011] [Indexed: 12/19/2022]
Abstract
With up to 400 million affected people worldwide, chronic hepatitis B virus (HBV) infection is still a major health care problem. During the last decade, several novel therapeutic approaches have been developed and evaluated. In most regions of the world, interferon-α, and nucleos(t)ide analogues (NUCs) are currently approved. Despite major improvements, none of the existing therapies is optimal since viral clearance is rarely achieved. Recently, a better understanding of the HBV life cycle and the development of novel model systems of HBV infection have led to the development of novel antiviral strategies and drug targets. This review will focus on current and potential future drug targets in the HBV life cycle and strategies to modulate the virus-host interaction.
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Affiliation(s)
- Daniel Grimm
- Department of Medicine II, University of Freiburg, Freiburg, Germany
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21
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Snow-Lampart A, Chappell B, Curtis M, Zhu Y, Myrick F, Schawalder J, Kitrinos K, Svarovskaia ES, Miller MD, Sorbel J, Heathcote J, Marcellin P, Borroto-Esoda K. No resistance to tenofovir disoproxil fumarate detected after up to 144 weeks of therapy in patients monoinfected with chronic hepatitis B virus. Hepatology 2011; 53:763-73. [PMID: 21374657 DOI: 10.1002/hep.24078] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Accepted: 11/08/2010] [Indexed: 12/14/2022]
Abstract
UNLABELLED Tenofovir disoproxil fumarate (TDF) is a nucleotide analogue with potent activity against human immunodeficiency virus type 1 and hepatitis B virus (HBV). To date, no reports of HBV clinical resistance to TDF have been confirmed. In two phase 3 studies (GS-US-174-0102 and GS-US-174-0103), 375 hepatitis B e antigen-negative (HBeAg(-) ) patients and 266 HBeAg(+) patients with chronic hepatitis B (some nucleoside-naive and some lamivudine-experienced) were randomized 2:1 to receive TDF (n = 426) or adefovir dipivoxil (ADV; n = 215) for 48 weeks. After week 48, eligible patients received open-label TDF with no interruption. The studies are being continued through week 384/year 8; week 144 data are presented here. Per protocol, viremic patients (HBV DNA level ≥ 400 copies/mL or 69 IU/mL) had the option of adding emtricitabine (FTC) at or after week 72. Resistance analyses of HBV polymerase/reverse transcriptase (pol/RT) were based on population dideoxy sequencing. Phenotypic analyses were conducted in HepG2 cells with recombinant HBV derived from patient serum. Most patients maintained TDF monotherapy treatment across both studies (607/641, 95%). A resistance analysis of HBV pol/RT was performed at the baseline for all patients, for viremic patients at week 144 or at the last time when they were on TDF monotherapy (34 on TDF and 19 on ADV-TDF), and for patients who remained viremic after the addition of FTC (7/20 on TDF and 5/14 on ADV-TDF). No patient developed amino acid substitutions associated with resistance to TDF. Virological breakthrough on TDF monotherapy was infrequent over 144 weeks (13/426, 3%) and was attributed to documented nonadherence in most cases (11/13, 85%). Persistent viremia (≥400 copies/mL) through week 144 was rare (5/641, 0.8%) and was not associated with virological resistance to TDF by population or clonal analyses. CONCLUSION No nucleoside-naive or nucleoside-experienced patient developed HBV pol/RT mutations associated with TDF resistance after up to 144 weeks of exposure to TDF monotherapy.
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Reijnders JGP, Deterding K, Petersen J, Zoulim F, Santantonio T, Buti M, van Bömmel F, Hansen BE, Wedemeyer H, Janssen HLA. Antiviral effect of entecavir in chronic hepatitis B: influence of prior exposure to nucleos(t)ide analogues. J Hepatol 2010; 52:493-500. [PMID: 20185191 DOI: 10.1016/j.jhep.2010.01.012] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Revised: 08/31/2009] [Accepted: 10/05/2009] [Indexed: 12/24/2022]
Abstract
BACKGROUND & AIMS Entecavir is a potent inhibitor of viral replication in nucleos(t)ide analogue (NA)-naïve chronic hepatitis B patients, but data on the efficacy in NA-experienced subjects are limited. METHODS In a multi-center cohort study we investigated 161 chronic hepatitis B patients (34% NA-experienced) treated with entecavir monotherapy. RESULTS During a median follow-up of 11 (3-23)months, 82 (79%) of 104 NA-naïve patients achieved virologic response (VR), defined as HBV DNA <80IU/ml, and none of the patients (0%) developed genotypic entecavir-resistance. VR was demonstrated in 31 (54%) of 57 NA-experienced patients during a median follow-up of 12 (3-31)months. Patients with lamivudine-resistant mutations at the start of entecavir monotherapy had a reduced probability of achieving VR compared to lamivudine-naïve patients (HR 0.14; 95% CI 0.04-0.58; p=0.007). Antiviral efficacy was not decreased by prior treatment with lamivudine when lamivudine-resistance had never developed (HR 0.81; 95% CI 0.43-1.52; p=0.52). Prior adefovir therapy without development of adefovir-resistance (HR 0.84; 95% CI 0.43-1.64; p=0.61) and presence of adefovir-resistance (HR 0.86; 95% CI 0.27-2.71; p=0.80) did not influence antiviral response to entecavir. Switching to a tenofovir-containing treatment regimen resulted in viral load decline in patients with entecavir-resistance associated mutations. CONCLUSIONS Entecavir proved to be efficacious in NA-naïve patients. The antiviral efficacy of entecavir was not influenced by prior treatment with adefovir or presence of adefovir-resistance. Entecavir should not be used in patients with previous lamivudine-resistance, yet it may still be an option in lamivudine-experienced patients in case lamivudine-resistance never developed.
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Affiliation(s)
- Jurriën G P Reijnders
- Department of Gastroenterology and Hepatology, Erasmus MC, University Medical Center Rotterdam, Gravendijkwal 230, Room Ha 204, Rotterdam, The Netherlands
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Walsh AW, Langley DR, Colonno RJ, Tenney DJ. Mechanistic characterization and molecular modeling of hepatitis B virus polymerase resistance to entecavir. PLoS One 2010; 5:e9195. [PMID: 20169198 PMCID: PMC2820545 DOI: 10.1371/journal.pone.0009195] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2009] [Accepted: 01/06/2010] [Indexed: 01/25/2023] Open
Abstract
Background Entecavir (ETV) is a deoxyguanosine analog competitive inhibitor of hepatitis B virus (HBV) polymerase that exhibits delayed chain termination of HBV DNA. A high barrier to entecavir-resistance (ETVr) is observed clinically, likely due to its potency and a requirement for multiple resistance changes to overcome suppression. Changes in the HBV polymerase reverse-transcriptase (RT) domain involve lamivudine-resistance (LVDr) substitutions in the conserved YMDD motif (M204V/I ± L180M), plus an additional ETV-specific change at residues T184, S202 or M250. These substitutions surround the putative dNTP binding site or primer grip regions of the HBV RT. Methods/Principal Findings To determine the mechanistic basis for ETVr, wildtype, lamivudine-resistant (M204V, L180M) and ETVr HBVs were studied using in vitro RT enzyme and cell culture assays, as well as molecular modeling. Resistance substitutions significantly reduced ETV incorporation and chain termination in HBV DNA and increased the ETV-TP inhibition constant (Ki) for HBV RT. Resistant HBVs exhibited impaired replication in culture and reduced enzyme activity (kcat) in vitro. Molecular modeling of the HBV RT suggested that ETVr residue T184 was adjacent to and stabilized S202 within the LVDr YMDD loop. ETVr arose through steric changes at T184 or S202 or by disruption of hydrogen-bonding between the two, both of which repositioned the loop and reduced the ETV-triphosphate (ETV-TP) binding pocket. In contrast to T184 and S202 changes, ETVr at primer grip residue M250 was observed during RNA-directed DNA synthesis only. Experimentally, M250 changes also impacted the dNTP-binding site. Modeling suggested a novel mechanism for M250 resistance, whereby repositioning of the primer-template component of the dNTP-binding site shifted the ETV-TP binding pocket. No structural data are available to confirm the HBV RT modeling, however, results were consistent with phenotypic analysis of comprehensive substitutions of each ETVr position. Conclusions Altogether, ETVr occurred through exclusion of ETV-TP from the dNTP-binding site, through different, novel mechanisms that involved lamivudine-resistance, ETV-specific substitutions, and the primer-template.
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Affiliation(s)
- Ann W. Walsh
- Research and Development, Bristol-Myers Squibb Inc., Wallingford, Connecticut, United States of America
| | - David R. Langley
- Research and Development, Bristol-Myers Squibb Inc., Wallingford, Connecticut, United States of America
- * E-mail: (DRL); (DJT)
| | - Richard J. Colonno
- Research and Development, Bristol-Myers Squibb Inc., Wallingford, Connecticut, United States of America
| | - Daniel J. Tenney
- Research and Development, Bristol-Myers Squibb Inc., Wallingford, Connecticut, United States of America
- * E-mail: (DRL); (DJT)
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Stein LL, Loomba R. Drug targets in hepatitis B virus infection. Infect Disord Drug Targets 2009; 9:105-16. [PMID: 19275699 DOI: 10.2174/187152609787847677] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Hepatitis B virus infection (HBV) is a significant global health problem. Despite the success of universal hepatitis B vaccination in many countries, more than 350 million individuals worldwide are chronically infected and 15- 40% of those will develop cirrhosis and/or hepatocellular carcinoma if left untreated. Available therapies for chronic hepatitis B (CHB) infection are effective at decreasing viremia and improving measured clinical outcomes, however, no single therapy is optimal. As such, alternative drug therapies and the investigation of their role in the management of CHB are warranted. Significant improvements in the understanding of the HBV life cycle, viral genomics, and virus-host interactions continue to lead to the development of novel viral targets and immune modulators. Currently, two major classes of agents are utilized in CHB: the interferons and the nucleos(t)ide analogues. Each agent has individual advantages and drawbacks. The development of specific antiviral therapy has led to the emergence of HBV drug-resistant strains that has limited the long-term therapeutic potential of available agents. This necessitates the development of new agents that target both wild-type and drug-resistant strains. Further understanding of the basic mechanisms and clinical nuances of drug therapy is warranted. As most novel therapies are in the earliest stages of clinical development and testing, in the near future, treatment will continue to be long-term and likely involve the use of combination therapies to prevent viral resistance. In this review, we will highlight the HBV life cycle and genome, focusing in on current and potential novel antiviral drug targets as well as the benefits and clinical challenges with these therapies.
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Affiliation(s)
- Lance L Stein
- Division of Gastroenterology, Department of Medicine, University of California - San Diego, CA, USA
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25
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Zhu Y, Curtis M, Qi X, Miller MD, Borroto-Esoda K. Anti-hepatitis B virus activity in vitro of combinations of tenofovir with nucleoside/nucleotide analogues. Antivir Chem Chemother 2009; 19:165-76. [PMID: 19374144 DOI: 10.1177/095632020901900404] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Long-term management of some chronic hepatitis B patients might require combination therapy using drugs with distinct resistance profiles to sustain viral suppression and to reduce the resistance-associated failure. Tenofovir disoproxil fumarate (TDF), approved for hepatitis B virus (HBV) and HIV-1 treatment, is active against wildtype HBV and HBV containing YMDD mutations, which confer resistance to emtricitabine (FTC), lamivudine (3TC) and telbivudine (LdT) and contribute to entecavir (ETV) resistance. We therefore evaluated the in vitro anti-HBV activity of tenofovir (TFV), the active parent drug of TDF, combined with FTC, 3TC, ETV, LdT and adefovir (AFV). METHODS The anti-HBV activities of the compounds were tested using the AD38 cell line that expresses wild-type HBV from a tetracycline-controllable promoter. Intracellular HBV DNA levels were quantified using real-time PCR assay and cytotoxicities were assessed with XTT assays. The antiviral data of the drug combinations were evaluated using MacSynergy analyses on the basis of the Bliss independence model as well as isobologram analyses on the basis of the Loewe additivity theory. RESULTS All drug combinations tested, FTC+TFV, 3TC+TFV, ETV+TFV, LdT+TFV and AFV+TFV, showed additive antiviral interactions as analysed by MacSynergy. Isobologram analyses revealed that these combination pairs were additive, with the exception of FTC+TFV, which demonstrated slight synergistic activity. No cytotoxic or antagonistic effects were observed with any of the combinations tested. CONCLUSIONS The combination of TFV with FTC, 3TC, ETV, LdT or AFV had additive to slightly synergistic anti-HBV effects in vitro. These results support the use of TDF as a component in combination regimens with currently available anti-HBV nucleoside analogues.
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Affiliation(s)
- Yuao Zhu
- Gilead Sciences, Inc, Durham, NC, USA.
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Tenney DJ, Rose RE, Baldick CJ, Pokornowski KA, Eggers BJ, Fang J, Wichroski MJ, Xu D, Yang J, Wilber RB, Colonno RJ. Long-term monitoring shows hepatitis B virus resistance to entecavir in nucleoside-naïve patients is rare through 5 years of therapy. Hepatology 2009; 49:1503-14. [PMID: 19280622 DOI: 10.1002/hep.22841] [Citation(s) in RCA: 653] [Impact Index Per Article: 43.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
UNLABELLED Patients with chronic hepatitis B virus (HBV) infection who develop antiviral resistance lose benefits of therapy and may be predisposed to further resistance. Entecavir (ETV) resistance (ETVr) results from HBV reverse transcriptase substitutions at positions T184, S202, or M250, which emerge in the presence of lamivudine (LVD) resistance substitutions M204I/V +/- L180M. Here, we summarize results from comprehensive resistance monitoring of patients with HBV who were continuously treated with ETV for up to 5 years. Monitoring included genotypic analysis of isolates from all patients at baseline and when HBV DNA was detectable by polymerase chain reaction (> or = 300 copies/mL) from Years 1 through 5. In addition, genotyping was performed on isolates from patients experiencing virologic breakthrough (> or = 1 log(10) rise in HBV DNA). In vitro phenotypic ETV susceptibility was determined for virologic breakthrough isolates, and for HBV containing novel substitutions emerging during treatment. The results over 5 years of therapy showed that in nucleoside-naïve patients, the cumulative probability of genotypic ETVr and genotypic ETVr associated with virologic breakthrough was 1.2% and 0.8%, respectively. In contrast, a reduced barrier to resistance was observed in LVD-refractory patients, as the LVD resistance substitutions, a partial requirement for ETVr, preexist, resulting in a 5-year cumulative probability of genotypic ETVr and genotypic ETVr associated with breakthrough of 51% and 43%, respectively. Importantly, only four patients who achieved < 300 copies/mL HBV DNA subsequently developed ETVr. CONCLUSION Long-term monitoring showed low rates of resistance in nucleoside-naïve patients during 5 years of ETV therapy, corresponding with potent viral suppression and a high genetic barrier to resistance. These findings support ETV as a primary therapy that enables prolonged treatment with potent viral suppression and minimal resistance.
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Affiliation(s)
- Daniel J Tenney
- Bristol-Myers Squibb Company Research and Development, Wallingford, CT 06492, USA.
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Reijnders JGP, LA Janssen H. New approaches in the management of chronic hepatitis B: role of tenofovir. Infect Drug Resist 2009; 2:13-26. [PMID: 21694884 PMCID: PMC3108728 DOI: 10.2147/idr.s3918] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
In the field of HIV management, tenofovir disoproxil fumarate (TDF) plays a pivotal role and has been demonstrated to be a safe and well-tolerated antiviral agent. Recent data showed the efficacy of TDF in the treatment of chronically hepatitis B virus (HBV)-infected patients. TDF was superior to adefovir dipivoxil (ADV) in both nucleos(t)ide-naïve HBeAg-positive and HBeAg-negative HBV patients, and appeared to be one of the most potent antiviral agents so far. In addition, several reports showed that TDF was also effective in the nucleos(t)ide-experienced population, although conflicting results have been presented concerning patients with genotypic resistance to ADV. TDF seems to have a good resistance profile as well. The rtA194T mutation in association with lamivudine resistance may confer resistance to TDF, although both in vivo and in vitro studies regarding this mutation demonstrate conflicting results. As treatment with TDF may be associated with nephrotoxicity, all TDF-treated patients should be monitored for renal function at baseline and periodically thereafter. While the relative roles of interferon vs nucleos(t)ide analogues (NA) as initial anti-HBV therapy remains unclear, TDF will probably become one of the key factors in HBV management both as first-choice NA for nucleos(t)ide-naïve patients and as rescue therapy for nucleos(t)ide-experienced patients.
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Affiliation(s)
- Jurriën GP Reijnders
- Department of Gastroenterology and Hepatology, Erasmus University Medical Center Rotterdam, The Netherlands
| | - Harry LA Janssen
- Department of Gastroenterology and Hepatology, Erasmus University Medical Center Rotterdam, The Netherlands
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Amini-Bavil-Olyaee S, Herbers U, Sheldon J, Luedde T, Trautwein C, Tacke F. The rtA194T polymerase mutation impacts viral replication and susceptibility to tenofovir in hepatitis B e antigen-positive and hepatitis B e antigen-negative hepatitis B virus strains. Hepatology 2009; 49:1158-65. [PMID: 19263474 DOI: 10.1002/hep.22790] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
UNLABELLED Tenofovir is a new effective treatment option for patients with chronic hepatitis B, but could be potentially hampered by mutations in the hepatitis B virus (HBV) polymerase conferring drug resistance. Drug resistance may occur preferentially if long-term administration is required, for example, in patients with hepatitis B e antigen (HBeAg)-negative HBV infection bearing precore (PC) and basal core promoter (BCP) mutations. The rtA194T polymerase mutation has been found in HBV/HIV coinfected patients during tenofovir treatment and may be associated with tenofovir resistance. We generated replication-competent HBV constructs harboring rtA194T alone or in addition to lamivudine (LAM) resistance (rt180M + rtM204V), PC mutations, and BCP mutations and assessed their replicative capacity after transient transfection in human hepatoma cells. The rtA194T polymerase mutation alone or in conjunction with LAM resistance reduced the replication efficiency as compared with wild-type (WT) HBV. In contrast, combination of rtA194T (+/- LAM resistance) with HBeAg-negative PC or BCP mutants increased the replication capacity of the drug-resistant polymerase mutants, thereby restoring the viral replication to similar levels as WT clones. Clones harboring rtA194T showed partial resistance to tenofovir in vitro and also to LAM but remained susceptible to telbivudine and entecavir. CONCLUSION The rtA194T polymerase mutation is associated with partial tenofovir drug resistance and negatively impacts replication competence of HBV constructs. Viral replication, however, can be restored to WT levels, if these polymerase mutations occur together with precore or basic core promoter substitutions as found in HBeAg-negative hepatitis B. Patients with HBeAg-negative chronic HBV infection may therefore be at particular risk when developing drug resistance to tenofovir. Telbivudine or entecavir should be considered as effective alternative treatment options for these patients.
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Marcellin P, Heathcote EJ, Buti M, Gane E, de Man RA, Krastev Z, Germanidis G, Lee SS, Flisiak R, Kaita K, Manns M, Kotzev I, Tchernev K, Buggisch P, Weilert F, Kurdas OO, Shiffman ML, Trinh H, Washington MK, Sorbel J, Anderson J, Snow-Lampart A, Mondou E, Quinn J, Rousseau F. Tenofovir disoproxil fumarate versus adefovir dipivoxil for chronic hepatitis B. N Engl J Med 2008; 359:2442-55. [PMID: 19052126 DOI: 10.1056/nejmoa0802878] [Citation(s) in RCA: 859] [Impact Index Per Article: 53.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Tenofovir disoproxil fumarate (DF) is a nucleotide analogue and a potent inhibitor of human immunodeficiency virus type 1 reverse transcriptase and hepatitis B virus (HBV) polymerase. METHODS In two double-blind, phase 3 studies, we randomly assigned patients with hepatitis B e antigen (HBeAg)-negative or HBeAg-positive chronic HBV infection to receive tenofovir DF or adefovir dipivoxil (ratio, 2:1) once daily for 48 weeks. The primary efficacy end point was a plasma HBV DNA level of less than 400 copies per milliliter (69 IU per milliliter) and histologic improvement (i.e., a reduction in the Knodell necroinflammation score of 2 or more points without worsening fibrosis) at week 48. Secondary end points included viral suppression (i.e., an HBV DNA level of <400 copies per milliliter), histologic improvement, serologic response, normalization of alanine aminotransferase levels, and development of resistance mutations. RESULTS At week 48, in both studies, a significantly higher proportion of patients receiving tenofovir DF than of those receiving adefovir dipivoxil had reached the primary end point (P<0.001). Viral suppression occurred in more HBeAg-negative patients receiving tenofovir DF than patients receiving adefovir dipivoxil (93% vs. 63%, P<0.001) and in more HBeAg-positive patients receiving tenofovir DF than patients receiving adefovir dipivoxil (76% vs. 13%, P<0.001). Significantly more HBeAg-positive patients treated with tenofovir DF than those treated with adefovir dipivoxil had normalized alanine aminotransferase levels (68% vs. 54%, P=0.03) and loss of hepatitis B surface antigen (3% vs. 0%, P=0.02). At week 48, amino acid substitutions within HBV DNA polymerase associated with phenotypic resistance to tenofovir DF or other drugs to treat HBV infection had not developed in any of the patients. Tenofovir DF produced a similar HBV DNA response in patients who had previously received lamivudine and in those who had not. The safety profile was similar for the two treatments in both studies. CONCLUSIONS Among patients with chronic HBV infection, tenofovir DF at a daily dose of 300 mg had superior antiviral efficacy with a similar safety profile as compared with adefovir dipivoxil at a daily dose of 10 mg through week 48. (ClinicalTrials.gov numbers, NCT00116805 and NCT00117676.)
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Affiliation(s)
- Patrick Marcellin
- Hôpital Beaujon, Assistance Publique Hôpitaux de Paris, University of Paris 7 and INSERM Unité 773, Centre de Recherches Claude Bernard sur les Hepatites Virales, Clichy, France
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Abstract
The HBV genome variability is responsible for the complexitiy of the viral quasi-species and its evolution during the course of the infection. During antiviral therapy, the persistence of infected cells is another important determinant involved in the selection of drug resistant strains. The development of nucleoside analogs with complementary resistance profiles has provided the rationale for add-on strategies in case of virologic breakthrough. The current trend is to add antivirals earlier, before the rebound of viral load, especially in case of partial virologic response. Clinical trials are required to determine if a de novo combination of nucleoside analogs provides an added benefit compared to an early add-on strategy. However, de novo combination is recommended in patients whose liver functions cannot tolerate treatment failure, and in patients with a high risk of developing viral resistance because of a complex viral quasi-species prior to therapy.
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Abstract
This article summarizes the current state of antiviral therapy of hepatitis B with special attention given to areas that remain controversial or poorly defined. Strict adherence to liver association practice guidelines may result in missed opportunities to treat patients with significant underlying liver disease. In particular, recommended ALT thresholds may not appropriately reflect disease activity or degree of fibrosis. There is growing evidence that an alternative treatment paradigm for preventing late-stage disease complications may be indicated in highly viremic patients with early life exposure to hepatitis B. Pegylated interferon therapy is often a better choice for young to middle-aged patients with genotype A and B because of the higher rate of HBeAg seroconversion and a greater chance for HBsAg seroconversion in both HBeAg-positive and -negative patients as compared to nucleoside analogs. Nucleoside analog monotherapy is the current standard of care for many patients. However, long-term monotherapy results in resistance to a variable degree and sequential monotherapy may result in multi-drug resistant virus. Which patients would specifically benefit from early combination therapy also remains poorly defined. The rapidity and robustness of the suppression of HBV DNA while on a nucleoside analog should be monitored relatively early during treatment because it affects treatment outcome and the rate of resistance. While great progress has been made in treating hepatitis B, many important issues require further study.
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Fournier C, Zoulim F. Antiviral therapy of chronic hepatitis B: prevention of drug resistance. Clin Liver Dis 2007; 11:869-92, ix. [PMID: 17981233 DOI: 10.1016/j.cld.2007.08.013] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The emergence of viral resistance during treatment is becoming an important clinical issue for hepatitis B virus (HBV) antiviral therapy. Considerable progress has been achieved in the efficacy of treatment, with the development of new drugs that allow a sustained suppression of HBV replication, or at least maintain the viral load below a clinically relevant threshold. Although most drugs currently registered for the treatment of chronic hepatitis B are effective in suppressing viral load, long-term therapy is required to avoid viral reactivation and progression of liver disease. Because of the variability of the HBV genome, such long-term treatments are associated with the emergence of resistant viral strains, which may compromise the initial clinical benefit of the treatment.
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Affiliation(s)
- Claire Fournier
- Hospices Civils de Lyon, Hôtel Dieu, Service d'hépato-gastroentérologie, 69002 Lyon, France
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