Selim Gurel
Uludağ University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Selim Gurel.
Gastroenterology | 2011
E. Jenny Heathcote; Patrick Marcellin; Maria Buti; Edward Gane; Robert A. de Man; Zahary Krastev; George Germanidis; Samuel S. Lee; Robert Flisiak; Kelly Kaita; Michael P. Manns; Iskren Kotzev; Konstantin Tchernev; Peter Buggisch; Frank Weilert; Oya Ovunc Kurdas; Mitchell L. Shiffman; Huy N. Trinh; Selim Gurel; Andrea Snow–Lampart; Katyna Borroto–Esoda; Elsa Mondou; Jane Anderson; Jeff Sorbel; Franck Rousseau
BACKGROUND & AIMS Tenofovir disoproxil fumarate (TDF), a nucleotide analogue and potent inhibitor of hepatitis B virus (HBV) polymerase, showed superior efficacy to adefovir dipivoxil in treatment of chronic hepatitis B through 48 weeks. We evaluated long-term efficacy and safety of TDF monotherapy in patients with chronic hepatitis B who were positive or negative for hepatitis B e antigen (HBeAg(+) or HBeAg(-)). METHODS After 48 weeks of double-blind comparison of TDF to adefovir dipivoxil, patients who underwent liver biopsy were eligible to continue the study on open-label TDF for 7 additional years; data presented were collected up to 3 years (week 144) from 85% of participants. Primary efficacy end points at week 144 included levels of HBV DNA and alanine aminotransferase, development of resistance mutations, and presence of HBeAg or hepatitis B surface antigen (HBsAg). RESULTS At week 144, 87% of HBeAg(-) and 72% of HBeAg(+) patients treated with TDF had levels of HBV DNA <400 copies/mL. Among patients who had previously received adefovir dipivoxil and then received TDF, 88% of the HBeAg(-) and 71% of the HBeAg(+) patients had levels of HBV DNA <400 copies/mL; overall, 81% and 74%, respectively, maintained normalized levels of alanine aminotransferase and 34% had lost HBeAg. Amino acid substitutions in HBV DNA polymerase that are associated with resistance to tenofovir were not detected in any patient. Cumulatively, 8% of HBeAg(+) patients lost HBsAg. TDF maintained a favorable safety profile for up to 3 years. CONCLUSIONS TDF was safe and effective in the long-term management of HBeAg(+) and HBeAg(-) patients with chronic hepatitis B.
Gastroenterology | 2009
Patrick Marcellin; George K. K. Lau; Patrizia Farci; Cihan Yurdaydin; Teerha Piratvisuth; Rui Jin; Selim Gurel; Zhi-Meng Lu; Jian Wu; Matei Popescu; Stephanos J. Hadziyannis
BACKGROUND & AIMS Patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B treated with peginterferon alpha-2a with or without lamivudine achieve significantly higher 6-month posttreatment rates of response compared with those treated with lamivudine alone. The durability of <or=3-year posttreatment response was investigated in this study. METHODS Patients received peginterferon alpha-2a only (180 microg once weekly; n = 177), in combination with lamivudine (100 mg daily; n = 179) or lamivudine alone (n = 181) for 48 weeks. A total of 315 patients (116, 114, and 85, respectively) participated in this posttreatment observational study. RESULTS Three years after treatment, the percentage of patients with normal alanine aminotransferase (ATL) was higher for patients treated with peginterferon alpha-2a (31%) than with lamivudine (18%; P = 0.032). Similarly, 28% of patients treated with peginterferon had hepatitis B virus (HBV) DNA levels <or= 10,000 copies/mL versus 15% of patients treated with lamivudine (P = .039). Peginterferon alpha-2a treatment and high baseline ALT level were independent baseline predictors of long-term virologic response (P = .040 and P = .01, respectively). Of the patients who had been treated with a peginterferon alpha-2a-containing regimen, 8.7% cleared hepatitis B surface antigen (HBsAg; 44% of those with undetectable HBV at 3-year posttreatment follow-up) compared with none treated with lamivudine alone. CONCLUSIONS Biochemical and virologic responses were sustained for <or=3 years in approximately 25% of patients given a 48-week course of peginterferon alpha-2a, with or without lamivudine. The increased rate of HBsAg clearance in patients with HBeAg-negative chronic hepatitis B supports the use of peginterferon alpha-2a as a first-line treatment.
Gut | 2007
Patrick Marcellin; Gk Lau; Stephanos J. Hadziyannis; Rui Jin; Teerha Piratvisuth; Georgios Germanidis; Cihan Yurdaydin; M. Diago; Selim Gurel; My Lai; Maurizia Rossana Brunetto; Patrizia Farci; Matei Popescu; Philip McCloud
Objective: In a trial of patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B, 24 week post-treatment biochemical and virological response rates with peginterferon α-2a with or without lamivudine were significantly higher than with lamivudine alone. The effect of pre-treatment factors on post-treatment responses was investigated. Methods: Multivariate analyses were performed using available data from 518 patients treated with peginterferon α-2a with or without lamivudine, or with lamivudine alone. A post-treatment response was defined as alanine aminotransferase (ALT) normalisation and hepatitis B virus (HBV) DNA level of <20 000 copies/ml. Results: In logistic regression analyses across all treatment arms, peginterferon α-2a (with or without lamivudine) therapy, younger age, female gender, high baseline ALT, low baseline HBV DNA and HBV genotype were identified as significant predictors of combined response at 24 weeks post-treatment. In the peginterferon α-2a and lamivudine monotherapy arms, patients with genotypes B or C had a higher chance of response than genotype D infected patients (p<0.001), the latter responding better to the combination than to peginterferon α-2a monotherapy (p = 0.015). At 1 year post-treatment, response rates by intention-to-treat analysis were 19.2% for the peginterferon α-2a, 19.0% for the combination, and 10.0% for the lamivudine groups, with genotypes B or C associated with a sustained combined response to peginterferon α-2a with or without lamivudine therapy. Conclusions: Baseline ALT and HBV DNA levels, patient age, gender, and infecting HBV genotype significantly influenced combined response at 24 weeks post-treatment, in patients treated with peginterferon α-2a and/or lamivudine. At 1 year post-treatment HBV genotype was significantly predictive of efficacy for patients treated with peginterferon α-2a with or without lamivudine.
The New England Journal of Medicine | 2011
Heiner Wedemeyer; Cihan Yurdaydin; George N. Dalekos; A. Erhardt; Yilmaz Cakaloglu; Halil Degertekin; Selim Gurel; Stefan Zeuzem; Kalliopi Zachou; Hakan Bozkaya; Armin Koch; Thomas Bock; Hans Peter Dienes; Michael P. Manns
BACKGROUND Chronic infection with hepatitis B virus and hepatitis delta virus (HDV) results in the most severe form of viral hepatitis. There is no currently approved treatment. We investigated the safety and efficacy of 48 weeks of treatment with peginterferon alfa-2a plus adefovir dipivoxil, peginterferon alfa-2a alone, and adefovir dipivoxil alone. METHODS We conducted a randomized trial in which 31 patients with HDV infection received treatment with 180 μg of peginterferon alfa-2a weekly plus 10 mg of adefovir daily, 29 received 180 μg of peginterferon alfa-2a weekly plus placebo, and 30 received 10 mg of adefovir alone weekly for 48 weeks. Follow-up was conducted for an additional 24 weeks. Efficacy end points included clearance of HDV RNA, normalization of alanine aminotransferase levels, and a decline in levels of hepatitis B surface antigen (HBsAg). RESULTS The primary end point--normalization of alanine aminotransferase levels and clearance of HDV RNA at week 48--was achieved in two patients in the group receiving peginterferon alfa-2a plus adefovir and two patients in the group receiving peginterferon alfa-2a plus placebo but in none of the patients in the group receiving adefovir alone. At week 48, the test for HDV RNA was negative in 23% of patients in the first group, 24% of patients in the second, and none of those in the third (P = 0.006 for the comparison of the first and third groups; P = 0.004 for the comparison of the second and third). The efficacy of peginterferon alfa-2a was sustained for 24 weeks after treatment, with 28% of the patients receiving peginterferon alfa-2a plus adefovir or peginterferon alfa-2a alone having negative results on HDV-RNA tests; none of the patients receiving adefovir alone had negative results. A decline in HBsAg levels of more than 1 log(10) IU per milliliter from baseline to week 48 was observed in 10 patients in the first group, 2 in the second, and none in the third (P<0.001 for the comparison of the first and third groups and P = 0.01 for the comparison of the first and second). CONCLUSIONS Treatment with peginterferon alfa-2a for 48 weeks, with or without adefovir, resulted in sustained HDV RNA clearance in about one quarter of patients with HDV infection. (Current Controlled Trials number, ISRCTN83587695.).
Canadian Journal of Gastroenterology & Hepatology | 2003
Murat Kiyici; Macit Gülten; Selim Gurel; Selim Giray Nak; Enver Dolar; Gursel Savci; Saduman Balaban Adim; Omer Yerci; Faruk Memik
BACKGROUND/AIMS Nonalcoholic steatohepatitis (NASH) is a serious disorder with the potential to gradually progress to cirrhosis. It is generally associated with obesity, diabetes and hyperlipidemia. Currently, there is no established therapy for NASH. The aim of the present study was to evaluate the effectiveness of atorvastatin and ursodeoxycholic acid (UDCA) in the treatment of NASH. METHODS This prospective study included 44 adult patients (24 men, 20 women) with a mean age of 48.90+/-7.69 years and mean body mass index (BMI) of 29.40+/-3.82. Ten patients had a history of diabetes. Serological markers for viral hepatitis were negative in all patients and there was no history of alcohol or drug abuse. Patients who had autoimmune hepatitis were excluded from the study. Liver biopsy was performed before therapy to confirm the diagnosis. Among NASH patients, 17 normolipidemic cases received UDCA 13 to 15 mg/kg/day (group 1), while hyperlipidemic cases (n=27) received atorvastatin 10 mg/day (group 2) for six months. The BMI, serum lipids, liver function tests and liver density, assessed by computerized tomography, were evaluated before and after the treatment period. The BMI, serum aminotransferase levels, histological parameters (steatosis, inflammation, fibrosis scores) and liver densities were not statistically different between the groups at the beginning of therapy. RESULTS The BMI, serum glucose, and triglyceride levels did not change in either group after the treatment period. In group 1, serum alanine aminotransferase (ALT) and gamma-glutamyl-transferase (GGT) levels reduced significantly, and in group 2, serum cholesterol, aspartate aminotransferase, ALT, alkaline phosphatase and GGT levels reduced significantly. Liver densities increased only in group 2, probably as a result of diminishing fat content of liver. The normalization of transaminases was also more prevalent in group 2. Liver steatosis was closely correlated with liver density, but inflammation and fibrosis were not. CONCLUSIONS The use of atorvastatin in NASH patients with hyperlipidemia was found to be both effective and safe. The benefit of statin and UDCA therapy in normolipidemic patients with NASH requires confirmation with further placebo-controlled trials.
Gastroenterology | 2014
S. Fung; Peter Kwan; Milotka Fabri; Andrzej Horban; Mijomir Pelemis; Hie-Won Hann; Selim Gurel; Florin A. Caruntu; John F. Flaherty; Benedetta Massetto; Phillip Dinh; Amoreena Corsa; G. Mani Subramanian; John G. McHutchison; Petr Husa; Edward Gane
BACKGROUND & AIMS Tenofovir disoproxil fumarate (TDF) is active against lamivudine-resistant hepatitis B virus (HBV) infection, but data to support its clinical efficacy in this setting are limited. METHODS In a prospective, double-blind, 96-week trial, patients were randomly assigned (1:1) to groups given TDF (300 mg, n = 141) or a combination of emtricitabine (FTC, 200 mg; n = 139) and TDF (300 mg, FTC/TDF). Patients were hepatitis B e antigen (HBeAg)-positive or HBeAg-negative, with levels of HBV DNA ≥3 log10 IU/mL and lamivudine resistance mutations (HBV polymerase or reverse transcriptase amino acid substitutions rtM204I/V ± rtL180M by INNO-LiPA Multi-DR v3; Innogenetics, Inc, Alpharetta, GA). The primary end point was proportion with HBV DNA <69 IU/mL (Roche COBAS Taqman assay; Roche Molecular Systems, Inc, Pleasanton, CA). RESULTS Patient groups were well matched for demographic and disease characteristics, including region (60% from Europe), HBV genotype (45% genotype D), HBeAg status (47% HBeAg-positive), and duration of lamivudine treatment (mean, 3.8 years). At week 96 of treatment, 89.4% of patients in the TDF group and 86.3% in the FTC/TDF group had levels of HBV DNA <69 IU/mL (P = .43). HBeAg loss and seroconversion did not differ between groups; only 1 patient (0.7%) in the FTC/TDF group lost hepatitis B surface antigen. Treatment was well tolerated; confirmed renal events (creatinine increase of ≥0.5 mg/dL [>44 umol/L], creatinine clearance <50 mL/min, or level of PO4 <2 mg/dL [<0.65 mmol/L]) were generally mild and infrequent (<1%). Small reductions (<2%) in mean bone mineral density of hip and spine were detected by dual-energy x-ray absorptiometry in both groups. No TDF resistance developed through 96 weeks of treatment. CONCLUSIONS TDF alone is safe and effective for treatment of patients with lamivudine-resistant, chronic HBV infection. Clinical Trials.gov No, NCT00737568.
Hepatology | 2014
B. Heidrich; Cihan Yurdaydin; Gökhan Kabaçam; Boris A. Ratsch; Kalliopi Zachou; B. Bremer; George N. Dalekos; A. Erhardt; Fehmi Tabak; Kendal Yalçin; Selim Gurel; Stefan Zeuzem; Markus Cornberg; C.-Thomas Bock; Michael P. Manns; Heiner Wedemeyer
Interferon alpha is the only treatment option for hepatitis delta virus (HDV). Trials investigating the efficacy of pegylated interferon alpha (PEG‐IFNa) showed HDV RNA negativity rates of 25‐30% 24 weeks after therapy. However, the clinical and virological long‐term outcome of HDV‐infected patients treated with PEG‐IFNa is unknown. We performed a retrospective‐prospective follow‐up of 77 patients treated for 48 weeks with either PEG‐alfa‐2a and adefovir (ADV) or either drug alone in the Hep‐Net‐International‐Delta‐Hepatitis‐Intervention‐Study 1 (HIDIT‐1) trial. Long‐term follow‐up data were available for 58 out of 77 patients (75%) with a median time of follow‐up of 4.5 (0.5‐5.5) years and a median 3 visits per patient. Patients treated with ADV alone received retreatment with PEG‐IFNa (48% versus 19%; P = 0.02) more often. Hepatitis B virus surface antigen (HBsAg) became negative in six PEG‐IFNa‐treated patients until the end of long‐term follow‐up (10%). Sixteen patients tested HDV RNA‐negative 6 months after PEG‐IFNa treatment who were entered in the long‐term follow‐up study. Out of these, nine individuals tested HDV RNA‐positive at least once during further long‐term follow‐up, with seven patients being HDV RNA‐positive at the most recent visit. Clinical endpoints (liver‐related death, liver transplantation, hepatic decompensation, hepatocellular carcinoma) were observed in three PEG‐IFNa‐treated (8%) and three ADV‐treated (14%) patients during posttreatment long‐term follow‐up with an overall annual event rate of 2.5% (4.9% in cirrhosis). Sequencing confirmed the reappearance of pretreatment virus strains in all cases. Conclusion: Late HDV RNA relapses may occur after PEG‐IFNa therapy of hepatitis delta and thus the term sustained virological response should be avoided in HDV infection. The annual posttreatment rate of clinical events in hepatitis delta patients eligible for PEG‐IFNa therapy is about 2.5% and 4.9% in patients with cirrhosis. (Hepatology 2014;60:87‐97)
Journal of Hepatology | 2002
Cihan Yurdaydin; Hakan Bozkaya; Selim Gurel; Hans L. Tillmann; N. Aslan; A. Okcu-Heper; Esra Erden; Kendal Yalçin; Nevzat Iliman; Ozden Uzunalimoglu; Michael P. Manns; A. Mithat Bozdayi
BACKGROUND/AIMS Interferon is the only established therapy for chronic delta hepatitis and alternative treatment options are an urgent need. Since successful treatment of a case of post-transplant delta hepatitis with the nucleoside analogue famciclovir had been reported, a pilot study was undertaken to evaluate the use of famciclovir in the treatment of chronic delta hepatitis. METHODS A total of 15 adult patients, 13 men, two women, ages 20-52 years, with chronic delta hepatitis were treated with famciclovir, 500 mg, three times a day for 6 months and were then followed-up for 6 months posttreatment. All patients had compensated chronic liver disease, elevated liver enzymes and were hepatitis delta virus (HDV) RNA positive by polymerase chain reaction at baseline. Patients were monitored and tested for HBsAg, hepatitis B virus (HBV) DNA and HDV RNA levels. Liver biopsies were obtained before starting famciclovir and within 1 month of completion of treatment. RESULTS HBV DNA levels decreased in nine of the 15 patients and levels rose again after treatment (P<0.05). Famciclovir had no effect on alanine aminotransferase (ALT) and HBsAg levels or on serum HDV RNA and overall, there was no improvement in liver histology. CONCLUSIONS Treatment of chronic delta hepatitis with famciclovir has no effect on disease activity and HDV RNA levels.
Liver International | 2010
Kalliopi Zachou; Cihan Yurdaydin; Uta Drebber; George N. Dalekos; A. Erhardt; Yilmaz Cakaloglu; Halil Degertekin; Selim Gurel; Stefan Zeuzem; Hakan Bozkaya; Verena Schlaphoff; Hans Peter Dienes; Thomas Bock; Michael P. Manns; Heiner Wedemeyer
Background: Hepatitis delta virus (HDV) causes severe liver disease.
Journal of Hepatology | 1998
Sabahattin Kaymakoglu; Yilmaz Cakaloglu; Kadir Demir; Salih Turkoglu; Selim Badur; Selim Gurel; Fatih Besisik; Ugur Cevikbas; Atilla Ökten
BACKGROUND/AIMS It has been reported that severe cryptogenic chronic hepatitis may be a subgroup of autoimmune hepatitis. The aims of this study were to investigate the clinical features, liver function tests, human leukocyte antigens and response to immunosuppressive therapy in severe cryptogenic chronic hepatitis, and to compare the findings in such patients with those in patients with autoimmune hepatitis. METHODS History of alcohol and hepatotoxic drug intake, markers of metabolic liver disease, autoantibodies (antinuclear antibody, smooth muscle antibody, antibody to liver/kidney microsome type 1), and viral markers (HBsAg, HBV DNA, anti-HCV, HCV RNA) were negative in all severe cryptogenic chronic hepatitis patients (histological activity index > 9 and alanine aminotransferase level > 2 x normal). Fifteen cryptogenic patients (13 women; mean age, 33 +/- 16 years) and seven autoimmune patients (seven women; mean age, 28 +/- 3.9 years; five type 1; two type 2a) received prednisolone and azathioprine for at least 2 years. RESULTS Cryptogenic chronic hepatitis patients were similar to patients with autoimmune hepatitis with respect to age, sex, clinical presentation, liver function tests and Knodell scores at admission. HLA phenotype frequencies were comparable between cryptogenic and autoimmune groups: BW6 (77% vs. 100%), DR4 (62% vs. 57%), and HLA B8 (15% vs. 43%). The rates of complete and partial remissions achieved during therapy were 87% vs. 57% and 13% vs. 29%, respectively (p > 0.05). CONCLUSIONS The clinical, biochemical and HLA phenotypic features, and the responsiveness to immunosuppressive therapy in severe cryptogenic chronic hepatitis support the idea that it may be an autoimmune liver disease similar to autoimmune hepatitis.