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Featured researches published by Tsugiko Oze.


Journal of Viral Hepatitis | 2009

Ribavirin dose reduction raises relapse rate dose-dependently in genotype 1 patients with hepatitis C responding to pegylated interferon alpha-2b plus ribavirin

Naoki Hiramatsu; Tsugiko Oze; Takayuki Yakushijin; Yuko Inoue; Takumi Igura; Kiyoshi Mochizuki; Kazuho Imanaka; Akira Kaneko; Masahide Oshita; Hideki Hagiwara; Eiji Mita; Toshihiko Nagase; Toshifumi Ito; Yoshiaki Inui; Taizo Hijioka; Kazuhiro Katayama; Shinji Tamura; Harumasa Yoshihara; Yasuharu Imai; Motohiko Kato; Yuichi Yoshida; Tomohide Tatsumi; Kazuyoshi Ohkawa; Shinichi Kiso; Tatsuya Kanto; Akinori Kasahara; Tetsuo Takehara; Norio Hayashi

Summary.  The impact of ribavirin exposure on virologic relapse remains controversial in combination therapy with pegylated interferon (Peg‐IFN) and ribavirin for patients with chronic hepatitis C (CH‐C) genotype 1. The present study was conducted to investigate this. Nine hundred and eighty‐four patients with CH‐C genotype 1 were enrolled. The drug exposure of each medication was calculated by averaging the dose actually taken. For the 472 patients who were HCV RNA negative at week 24 and week 48, multivariate logistic regression analysis showed that the degree of fibrosis (P = 0.002), the timing of HCV RNA negativiation (P < 0.001) and the mean doses of ribavirin (P < 0.001) were significantly associated with relapse, but those of Peg‐IFN were not. Stepwise reduction of the ribavirin dose was associated with a stepwise increase in relapse rate from 11% to 60%. For patients with complete early virologic response (c‐EVR) defined as HCV RNA negativity at week 12, only 4% relapse was found in patients given ≥12 mg/kg/day of ribavirin and ribavirin exposure affected the relapse even after treatment week 12, while Peg‐IFN could be reduced to 0.6 μg/kg/week after week 12 without the increase of relapse rate. Ribavirin showed dose‐dependent correlation with the relapse. Maintaining as high a ribavirin dose as possible (≥12 mg/kg/day) during the full treatment period can lead to suppression of the relapse in HCV genotype 1 patients responding to Peg‐IFN alpha‐2b plus ribavirin, especially in c‐EVR patients.


Clinical Gastroenterology and Hepatology | 2014

Post-treatment Levels of α-Fetoprotein Predict Incidence of Hepatocellular Carcinoma After Interferon Therapy

Tsugiko Oze; Naoki Hiramatsu; Takayuki Yakushijin; Masanori Miyazaki; Akira Yamada; Masahide Oshita; Hideki Hagiwara; Eiji Mita; Toshifumi Ito; Hiroyuki Fukui; Yoshiaki Inui; Taizo Hijioka; Masami Inada; Kazuhiro Katayama; Shinji Tamura; Harumasa Yoshihara; Atsuo Inoue; Yasuharu Imai; Eijiro Hayashi; Michio Kato; Takuya Miyagi; Yuichi Yoshida; Tomohide Tatsumi; Akinori Kasahara; Toshimitsu Hamasaki; Norio Hayashi; Tetsuo Takehara

BACKGROUND & AIMS In patients with chronic hepatitis C virus (HCV) infection, lack of sustained virologic response (SVR) 24 weeks after the end of interferon therapy is a significant risk factor for hepatocellular carcinoma (HCC). Although many pretreatment factors are known to affect HCC incidence, less is known about post-treatment factors-many change during the course of interferon therapy. METHODS We performed a prospective study, collecting data from 2659 patients with chronic hepatitis C without a history of HCC who had been treated with pegylated interferon (Peg-IFN) plus ribavirin from 2002 through 2008 at hospitals in Japan. Biopsy specimens were collected before treatment; all patients received Peg-IFN plus ribavirin for 48 to 72 weeks (HCV genotype 1) or 24 weeks (HCV genotype 2). Hematologic, biochemical, and virologic data were collected every 4 weeks during treatment and every 6 months after treatment. HCC was diagnosed based on angiography, computed tomography, and/or magnetic resonance imaging findings. RESULTS HCC developed in 104 patients during a mean observation period of 40 months. Older age, male sex, lower platelet counts and higher levels of α-fetoprotein at baseline, and lack of an SVR were significant risk factors for HCC. The cumulative incidence of HCC was significantly lower in patients without SVRs who relapsed than those with no response to treatment. Levels of α-fetoprotein 24 weeks after the end of treatment (AFP24) were significantly lower than levels of α-fetoprotein at baseline in patients with SVRs and those who relapsed, but not in nonresponders. Post-treatment risk factors for HCC among patients with SVRs included higher AFP24 level and older age; among those without SVRs, risk factors included higher AFP24 level, integrated level of alanine aminotransferase, older age, and male sex. AFP24 (≥10 ng/mL, 10-5 ng/mL, and then <5 ng/mL) was a better predictor of HCC incidence than pretreatment level of AFP among patients with and without SVRs. CONCLUSIONS In patients with chronic HCV infection, levels of α-fetoprotein decrease during interferon therapy. High post-treatment levels of α-fetoprotein predict HCC, regardless of whether patients achieve an SVR. University Hospital Medical Information Network Clinical Trials Registry: C000000196, C000000197.


Journal of Hepatology | 2011

Indications and limitations for aged patients with chronic hepatitis C in pegylated interferon alfa-2b plus ribavirin combination therapy

Tsugiko Oze; Naoki Hiramatsu; Takayuki Yakushijin; Kiyoshi Mochizuki; Masahide Oshita; Hideki Hagiwara; Eiji Mita; Toshifumi Ito; Hiroyuki Fukui; Yoshiaki Inui; Taizo Hijioka; Masami Inada; Kazuhiro Kaytayama; Shinji Tamura; Harumasa Yoshihara; Atsuo Inoue; Yasuharu Imai; Michio Kato; Takuya Miyagi; Yuichi Yoshida; Tomohide Tatsumi; Shinichi Kiso; Tatsuya Kanto; Akinori Kasahara; Tetsuo Takehara; Norio Hayashi

BACKGROUND & AIMS This study investigated the efficacy and adverse effects of pegylated interferon (Peg-IFN) plus ribavirin therapy in aged patients with chronic hepatitis C (CH-C). METHODS A total of 1040 naïve patients with CH-C (genotype 1, n=759; genotype 2, n=281), of whom 240 (23%) over 65 years old (y.o.), were treated with Peg-IFN alfa-2b plus ribavirin and assessed after being classified into five categories, according to age. RESULTS The discontinuance rate was higher for patients over 70 y.o. (36%), the most common reason being anemia. In the presence of genotype 1, the SVR rate was similar (42-46%) among patients under 65 y.o. and declined (26-29%) among patients over 65 y.o. For patients over 65 y.o., being male (Odds ratio, OR, 3.5, p=0.035) and EVR (OR, 83.3, p<0.001) were significant factors for SVR, in multivariate analysis. The Peg-IFN dose was related to EVR, and when EVR was attained, 76-86% of patients over 65 y.o. achieved SVR. SVR was not achieved (0/35, 0/38, respectively) if a 1-log decrease and a 2-log decrease were not attained at week 4 and week 8, respectively. In the presence of genotype 2, the SVR rate was similar (70-71%) among patients under 70 y.o. and declined among patients over 70 y.o. (43%). CONCLUSIONS Aged patients up to 65 y.o. with genotype 1 and 70 y.o. with genotype 2 can be candidates for Peg-IFN plus ribavirin therapy. The response-guided therapy can be applied for aged patients with genotype 1.


Hepatology Research | 2009

Effect of interferon α-2b plus ribavirin therapy on incidence of hepatocellular carcinoma in patients with chronic hepatitis.

Mika Kurokawa; Naoki Hiramatsu; Tsugiko Oze; Kiyoshi Mochizuki; Takayuki Yakushijin; Nao Kurashige; Yuko Inoue; Takumi Igura; Kazuho Imanaka; Akira Yamada; Masahide Oshita; Hideki Hagiwara; Eiji Mita; Toshifumi Ito; Yoshiaki Inui; Taizo Hijioka; Harumasa Yoshihara; Atsuo Inoue; Yasuharu Imai; Michio Kato; Shinichi Kiso; Tatsuya Kanto; Tetsuo Takehara; Akinori Kasahara; Norio Hayashi

Aim:  The objective of this study was to elucidate the long‐term effects of interferon (IFN)α‐2b plus ribavirin combination therapy and to clarify whether this therapy can reduce the incidence of hepatocellular carcinoma (HCC) in patients with chronic hepatitis C.


Journal of Viral Hepatitis | 2010

Factors affecting efficacy in patients with genotype 2 chronic hepatitis C treated by pegylated interferon alpha-2b and ribavirin: reducing drug doses has no impact on rapid and sustained virological responses.

Yuko Inoue; Naoki Hiramatsu; Tsugiko Oze; Takayuki Yakushijin; Kiyoshi Mochizuki; Hideki Hagiwara; Masahide Oshita; Eiji Mita; Hiroyuki Fukui; Masami Inada; Shinji Tamura; Harumasa Yoshihara; Eijirou Hayashi; Atsuo Inoue; Yasuharu Imai; Motohiko Kato; Takuya Miyagi; A. Hohsui; Hisashi Ishida; Shinichi Kiso; Tatsuya Kanto; Akinori Kasahara; Tetsuo Takehara; Norio Hayashi

Summary.  Reducing the dose of drug affects treatment efficacy in pegylated interferon (Peg‐IFN) and ribavirin combination therapy for patients with hepatitis C virus (HCV) genotype 1. The aim of this study was to investigate the impact of drug exposure, as well as the baseline factors and the virological response on the treatment efficacy for genotype 2 patients. Two‐hundred and fifty patients with genotype 2 HCV who were to undergo combination therapy for 24 weeks were included in the study, and 213 completed the treatment. Significantly more patients who achieved a rapid virological response (RVR), defined as HCV RNA negativity at week 4, achieved a sustained virological response (SVR) (92%, 122/133) compared with patients who failed to achieve RVR (48%, 38/80) (P < 0.0001). Multivariate logistic‐regression analysis showed that only platelet counts [odds ratio (OR), 1.68; confidence interval (CI), 1.002–1.139] and RVR (OR, 11.251; CI, 5.184–24.419) were independently associated with SVR, with no correlation being found for the mean dose of Peg‐IFN and ribavirin for RVR and SVR. Furthermore, in the stratification analysis of the timing of viral clearance, neither mean dose of Peg‐IFN (P = 0.795) nor ribavirin (P = 0.649) affected SVR in each group. Among the patients with RVR, the lowest dose group of Peg‐IFN (0.77 ± 0.10 μg/kg/week) and ribavirin (6.9 ± 0.90 mg/kg/day) showed 100% and 94% of SVR. Hence, RVR served as an important treatment predictor, and drug exposure had no impact on both SVR and RVR in combination therapy for genotype 2 patients.


Journal of Viral Hepatitis | 2009

Pegylated interferon alpha-2b (Peg-IFN α-2b) affects early virologic response dose-dependently in patients with chronic hepatitis C genotype 1 during treatment with Peg-IFN α-2b plus ribavirin.

Tsugiko Oze; Naoki Hiramatsu; Takayuki Yakushijin; Mika Kurokawa; Takumi Igura; Kiyoshi Mochizuki; Kazuho Imanaka; A. Yamada; Masahide Oshita; Hideki Hagiwara; Eiji Mita; Toshifumi Ito; Yoshiaki Inui; Taizo Hijioka; Shinji Tamura; Harumasa Yoshihara; Eijirou Hayashi; Atsuo Inoue; Yasuharu Imai; Motohiko Kato; Yuichi Yoshida; Tomohide Tatsumi; Kazuyoshi Ohkawa; Shinichi Kiso; Tatsuya Kanto; Akinori Kasahara; Tetsuo Takehara; Norio Hayashi

Summary.  Chronic hepatitis C (CH‐C) genotype 1 patients who achieved early virologic response have a high probability of sustained virologic response (SVR) following pegylated interferon (Peg‐IFN) plus ribavirin therapy. This study was conducted to evaluate how reducing drug doses affects complete early virologic response (c‐EVR) defined as hepatitis C virus (HCV) RNA negativity at week 12. Nine hundred eighty‐four patients with CH‐C genotype 1 were enrolled. Drug doses were evaluated independently on a body weight base from doses actually taken. From multivariate analysis, the mean dose of Peg‐IFN α‐2b during the first 12 weeks was the independent factor for c‐EVR (P = 0.02), not ribavirin. The c‐EVR rate was 55% in patients receiving ≥1.2 μg/kg/week of Peg‐IFN, and declined to 38% at 0.9–1.2 μg/kg/week, and 22% in patients given <0.9 μg/kg/week (P < 0.0001). Even with stratified analysis according to ribavirin dose, the dose‐dependent effect of Peg‐IFN on c‐EVR was observed, and similar c‐EVR rates were obtained if the dose categories of Peg‐IFN were the same. Furthermore, the mean dose of Peg‐IFN during the first 12 weeks affected HCV RNA negativity at week 24 (P < 0.0001) and SVR (P < 0.0001) in a dose‐dependent manner. Our results suggest that Peg‐IFN was dose‐dependently correlated with c‐EVR, independently of ribavirin dose. Thus, maintaining the Peg‐IFN dose as high as possible during the first 12 weeks can yield HCV RNA negativity and higher c‐EVR rates, leading to better SVR rates in patients with CH‐C genotype 1.


Journal of Gastroenterology | 2013

Association of enhanced activity of indoleamine 2,3-dioxygenase in dendritic cells with the induction of regulatory T cells in chronic hepatitis C infection

Koyo Higashitani; Tatsuya Kanto; Shoko Kuroda; Sachiyo Yoshio; Tokuhiro Matsubara; Naruyasu Kakita; Tsugiko Oze; Masanori Miyazaki; Mitsuru Sakakibara; Naoki Hiramatsu; Eiji Mita; Yasuharu Imai; Akinori Kasahara; Alato Okuno; Osamu Takikawa; Norio Hayashi; Tetsuo Takehara

BackgroundAltered functions of dendritic cells (DCs) and/or increases of regulatory T cells (Tregs) are involved in the pathogenesis of chronic hepatitis C virus (HCV) infection. A tryptophan-catabolizing enzyme, indoleamine 2,3-dioxygenase (IDO), is reported to be an inducer of immune tolerance. Our aim was to clarify whether or not IDO is activated in chronic hepatitis C patients and its role in immune responses.MethodsThis study enrolled 176 patients with chronic HCV infection and 37 healthy volunteers. Serum kynurenine concentration was evaluated by high-performance liquid chromatography, and its correlation with clinical parameters was examined. Monocyte-derived DCs were prepared from the subjects and subsequently stimulated with a combination of lipopolysaccharide and interferon-gamma to induce functional IDO (defined as IDO-DCs). The phenotypes, kynurenine or cytokine production, and T-cell responses with IDO-DCs were compared between the patients and healthy volunteers.ResultsThe serum kynurenine level in the patients was significantly higher than that in the healthy volunteers, and the level of serum kynurenine was positively correlated with the histological activity or fibrosis score. IDO activity in IDO-DCs from the patients was significantly higher than that in IDO-DCs from the volunteers. Furthermore, IDO-DCs from the patients induced more Tregs in vitro compared with those from the volunteers, and the frequency of induced Tregs by IDO-DCs was decreased with an IDO-specific inhibitor.ConclusionsSystemic IDO activity is enhanced in chronic hepatitis C patients in correlation with the degree of liver inflammation and fibrosis. In response to inflammatory stimuli, DCs from the patients tend to induce Tregs, with some of this action being dependent on IDO.


Hepatology Research | 2015

Suppression of hepatocellular carcinoma development in hepatitis C patients given interferon‐based antiviral therapy

Naoki Hiramatsu; Tsugiko Oze; Tetsuo Takehara

The advance of antiviral treatment for chronic hepatitis C has brought a high sustained virological response (SVR) rate. In this review article, the suppressive effect of interferon (IFN)‐based therapy on the development of hepatocellular carcinoma (HCC), risk factors for developing HCC and the characteristics of HCC development after SVR among chronic hepatitis C patients given IFN‐based therapy were studied. The HCC incidence has been revealed to decrease with IFN‐based antiviral therapy, especially in SVR, and the risk factors for developing HCC were older age, advanced liver fibrosis and male sex. α‐Fetoprotein levels at 24 weeks after the end of IFN‐based treatment was associated strongly with HCC incidence irrespective of virological response. In patients with SVR, other risk factors were glucose metabolism disorders, lipid metabolism disorders and alcohol intake. Extra attention to the possibility of HCC incidence should be required for these SVR patients. Antiviral therapy with a combination of HCV‐specific direct‐acting antivirals (DAA) is expected to be utilized in the future. However, it is not known whether DAA‐based treatment can suppress HCC to the level of IFN‐based treatment. Further research is required to clarify this.


Journal of Gastroenterology | 2006

Early decline of hemoglobin correlates with progression of ribavirin-induced hemolytic anemia during interferon plus ribavirin combination therapy in patients with chronic hepatitis C

Tsugiko Oze; Naoki Hiramatsu; Nao Kurashige; Natsuko Tsuda; Takayuki Yakushijin; Tatsuya Kanto; Tetsuo Takehara; Akinori Kasahara; Michio Kato; Harumasa Yoshihara; Kazuhiro Katayama; Shinji Kubota; Taizo Hijioka; Kazunobu Ishibashi; Masahide Oshita; Hideki Hagiwara; Yoshimichi Haruna; Eiji Mita; Shinji Tamura; Norio Hayashi

BackgroundThe aim of this study was to examine the factors correlated with the progression of ribavirin-induced hemolytic anemia in patients with chronic hepatitis C treated by interferon and ribavirin combination therapy.MethodsThis study was conducted on 505 patients by the Osaka Liver Disease Study Group. A decline of hemoglobin (Hb) concentration by 2 g/dl at the end of 2 weeks from the start of the treatment (“2 by 2” standard) was adopted as a predictive factor for progression to severe anemia. The ribavirin apparent clearance (CL/F) was also examined.ResultsOf 482 patients whose Hb value was more than 12 g/dl before the treatment, 68 patients (14%) had to discontinue ribavirin owing to severe anemia. Patients in the “2 by 2”-positive group (Hb decline over 2 g/dl) and the group with lower CL/F were significantly more likely to discontinue ribavirin owing to severe anemia. Discontinuation was more common among patients aged 60 years or older than for those under 60 years old (21% vs. 9%, P < 0.001). Among patients aged 60 years or older, only the “2 by 2” standard was significantly associated with the discontinuance of ribavirin owing to severe anemia in a multivariate analysis (odds ratio, 4.18; P < 0.001).ConclusionsThe “2 by 2” standard of Hb decline can be used to identify patients likely to develop severe anemia. The early reduction of ribavirin can help prevent progression to severe anemia, thus allowing ribavirin therapy to be completed even in older patients.


Hepatology Research | 2008

Early decline of hemoglobin can predict progression of hemolytic anemia during pegylated interferon and ribavirin combination therapy in patients with chronic hepatitis C

Naoki Hiramatsu; Nao Kurashige; Tsugiko Oze; Tetsuo Takehara; Shinji Tamura; Akinori Kasahara; Masahide Oshita; Kazuhiro Katayama; Harumasa Yoshihara; Yasuharu Imai; Michio Kato; Sumio Kawata; Hirohito Tsubouchi; Takeshi Okanoue; Shinichi Kakumu; Norio Hayashi

Aim:  Ribavirin, used to treat chronic hepatitis C, can induce hemolytic anemia, forcing the discontinuance of treatment. To establish a predictive measure to help circumvent this, we evaluated the relationship of hemoglobin (Hb) decline with the discontinuance of treatment during the progression of ribavirin‐induced anemia.

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