Antiviral Therapy 2015; 20: (doi: /IMP2805)

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1 Antiviral Therapy 2015; 20: (doi: /IMP2805) Original article Non-invasive fibrosis assessment predicts sustained virological response to telaprevir with pegylated interferon and ribavirin for chronic hepatitis C Eiichi Ogawa 1 *, Norihiro Furusyo 1, Motohiro Shimizu 1, Takeshi Ihara 1, Takeo Hayashi 1, Yuji Harada 1, Kazuhiro Toyoda 1, Masayuki Murata 1, Jun Hayashi 2 1 Department of General Internal Medicine, Kyushu University Hospital, Fukuoka, Japan 2 Kyushu General Internal Medicine Center, Haradoi Hospital, Fukuoka, Japan *Corresponding author eogawa@gim.med.kyushu-u.ac.jp Background: Liver fibrosis remains one of the most important predictors of sustained virological response (SVR) in this era of direct-acting antiviral treatment of chronic hepatitis C. We compare non-invasive fibrosis assessment with liver biopsy (METAVIR) in terms of their ability to predict SVR by telaprevir (TVR)-based triple therapy. Methods: This prospective study consisted of 108 patients with chronic HCV genotype 1 infection who received TVR in combination with pegylated interferon (PEG-IFN)-a2b and ribavirin (RBV). Non-invasive fibrosis data included transient elastography (FibroScan), FIB-4 index and aspartate aminotransferase to platelet ratio index (APRI). Results: SVR was achieved by 84.3% of the patients by intention-to-treat analysis. In contrast to the high SVR rates for treatment-naive patients (87.1%, 27 of 31) and patients who previously relapsed (97.9%, 46 of 47), the SVR rate of prior partial/null responders was significantly lower (60.0%, 18 of 30). The impact of fibrosis on SVR was greater for prior partial/null responders, and fibrosis data, including both METAVIR score and non-invasive fibrosis assessments, were useful for predicting SVR. The METAVIR score (area under the receiver operating characteristic curve [AUROC] 0.91, cutoff F2), FibroScan values (AUROC 0.99, cutoff 10.0 kpa), FIB-4 index (AUROC 0.91, cutoff 3.5) and APRI (AUROC 0.91, cutoff 0.80) were shown to have equal, excellent predictive power. Conclusions: An alternative to METAVIR score by liver biopsy, non-invasive fibrosis assessments are useful options for predicting SVR by prior partial or null responders in TVR-based triple therapy. Introduction Chronic HCV infection is a major cause of liver cirrhosis and hepatocellular carcinoma, affecting about 150 million people worldwide [1]. Eradication of HCV infection by antiviral treatment, as indicated by sustained virological response (SVR), has contributed to a reduction of the number of patients who develop hepatocellular carcinoma and hepatic decompensation and to prolonged survival [2 4]. Since the approval of directacting antivirals (DAAs) in 2011, the administration of two first-generation non-structural (NS) 3/4A protease inhibitors, telaprevir (TVR) and boceprevir, has resulted in significantly improved SVR rates for patients infected with HCV genotype 1 [5 8]. Many background factors associated with SVR to pegylated interferon-a (PEG-IFN-a) and ribavirin (RBV) do not appear to be significant predictors of response to TVR-based triple therapy based on the drastic improvement of treatment outcome. Nevertheless, the stage of fibrosis continues to be one of the most useful pretreatment predictors of success [6 9]. Pretreatment predictors of response are useful in selecting the most appropriate treatment, reducing the cost of therapy while optimizing treatment outcome. Japanese HCV patients, most of whom are elderly and have advanced fibrosis [10], need evaluation of the stage of fibrosis so that the treatment strategy can be individually tailored. In recent years, several routine laboratory tests such as aspartate aminotransferase (AST) to platelet ratio index (APRI) [11], FIB-4 index [12], and devices such as transient elastography (FibroScan) [13 15] have been developed and validated for the non-invasive assessment of advanced fibrosis or cirrhosis and serve as alternatives to liver biopsy. However, these 2015 International Medical Press (print) (online) 185

2 E Ogawa et al. non-invasive assessments have not been evaluated as predictors of antiviral treatment outcome. The aim of this study is to further compare the non-invasive assessment of fibrosis with METAVIR score by liver biopsy on their ability to assess predictors of the success of TVR-based triple therapy. Methods Patients This prospective study consisted of 108 Japanese patients with chronic HCV infection aged 20 years or older who received TVR in combination with PEG- IFN-a2b and RBV. All initiated treatment between December 2011 and December 2012 and it was completed by the end of June This study included both treatment-naive (n=31, 28.7%) and -experienced patients (n=77, 71.3%). Of the 77 patients previously treated with PEG-IFN-a and RBV, 47 (43.5%) had a relapse, 16 (14.8%) had partial response and 14 (13.0%) had null response. Exclusion criteria were: positivity for antibody to HIV or positivity for hepatitis B surface antigen; clinical or biochemical evidence of hepatic decompensation (Child Pugh B or C, ascites, bleeding varices or encephalopathy); other causes of liver disease (haemochromatosis, autoimmune hepatitis or primary biliary cirrhosis); excessive active alcohol consumption (a daily intake of more than 40g of ethanol), drug abuse or severe mental disorder; the presence of active cancer at entry; or treatment with antiviral or immunosuppressive agents prior to enrolment. The study was conducted in accordance with the ethical principles of the Declaration of Helsinki and was approved by the Ethics Committee of each participating hospital. Informed consent was obtained from all patients before enrolment. The study was registered on the University Hospital Medical Information Network (ID ). Clinical and laboratory assessment Clinical parameters were measured by standard laboratory techniques at a commercial laboratory (SRL Laboratory, Tokyo, Japan). Body mass index was calculated as weight in kilograms/height in square meters. The estimated glomerular filtration rate was calculated based on the Modification of Diet in Renal Disease formula. Human genomic DNA was extracted from peripheral blood. Genotyping of the interleukin-28b (IL28B; rs ) gene [16] was performed using the ABI TaqMan allelic discrimination kit (7500 Real Time PCR System; Applied Biosystems, Carlsbad, CA, USA). Liver biopsy was done by experienced hepatologists with a 16G disposable needle (Bard Monopty ; C.R.Bard, Covington, GA, USA) under ultrasound guidance. The minimum length of the liver sample was 15 mm and at least 10 complete portal tracts were necessary for inclusion. For each specimen, the stage of fibrosis was established according to the METAVIR score [17]. Non-invasive fibrosis assessment Transient elastography was performed at entry using FibroScan (Echosens, Paris, France) within two weeks of liver biopsy following the previously reported methods [14,15,18]. The FibroScan values are shown as kilopascal (kpa). All examinations were performed by accomplished operators each of whom had experienced over 200 examinations. Only liver stiffness measurements obtained with at least six successful acquisitions and a success rate of at least 60% were considered reliable. The validity of FibroScan values depends on an IQR of all successful measurements of less than 30% of median values [19]. The serum fibrosis markers used for assessment in this study were the APRI [11] and FIB-4 index [12]. APRI was calculated as AST (/upper limit of normal [U/L]) 100/platelet count ( 10 9 /l). The FIB-4 index was calculated from the published formula: [age (years) AST (U/L)] / [platelet count ( 10 9 /l) {alanine aminotransferase (U/L)} 1/2 ]. Antiviral treatment All patients received a combination treatment of TVR (Telavic; Mitsubishi Tanabe Pharma, Osaka, Japan), PEG-IFN-a2b (PEG-Intron; MSD, Tokyo, Japan) and RBV (Rebetol; MSD) for 12 weeks, followed by an additional 12 weeks of PEG-IFN-a2b and RBV alone. TVR 750 mg was administrated three times a day at an 8-h interval, after each meal. If the patient was female, aged over 65 or weighed less than 50 kg, the TVR dose of 1,500 mg/day (750 mg twice a day at a 12-h interval after each meal) could be initiated. PEG- IFN-a2b was injected subcutaneously once weekly at a dose of 1.5 mg/kg. RBV was given orally at a daily dose of 600 1,000 mg based on body weight. If marked anorexia, an elevation of serum creatinine, or severe anaemia developed, the TVR dose could be reduced from 2,250 to 1,500 mg/day, as previously reported [20]. For patients with grade 1 (localized to one or several sites) or 2 (diffuse skin eruption involving up to 50% of the body surface) dermatological disorders, medical management was performed at the discretion of the physicians at each hospital. If a progressive grade 3 dermatological disorder developed (involving more than 50% of the body surface or rash with the appearance of substantial systemic signs or symptoms), TVR was discontinued, but the patients International Medical Press

3 Non-invasive fibrosis assessment in TVR-based triple therapy continued to receive PEG-IFN-a2b and RBV. All treatment was discontinued if HCV RNA was more than 1,000 IU/ml at week 12 or later in case of viral breakthrough (defined as an increase of more than 1 log 10 IU/ml compared with the lowest recorded on-treatment value or a confirmed more than HCV RNA 100 IU/ml if previously below the level of quantification). HCV RNA level and HCV genotype Clinical follow-up of HCV viraemia was done by real-time reverse transcriptase PCR assay (COBAS TaqMan HCV assay; Roche Diagnostics, Tokyo, Japan) with a lower limit of quantitation of 15 IU/ml and an outer limit of quantitation of IU/ml (1.2 to 7.8 log IU/ml referred to log 10 IU/ml) [21]. The HCV RNA level was measured at baseline, at 4-week intervals during treatment, at early discontinuation and at follow-up visits after the end of treatment. HCV genotype determination was by sequence determination in the 5 -non-structual region of the HCV genome followed by phylogenetic analysis [22]. Previous virological response to PEG-IFN-a and RBV treatment was categorized as follows: prior relapse, undetectable HCV RNA at the end of treatment but detectable HCV RNA within 24 weeks after the end of treatment and the re-appearance of HCV RNA at any time during treatment after virological response (breakthrough); prior partial response, a more than 2 log 10 IU/ml decrease in the HCV RNA level from baseline at week 12 but detectable HCV RNA at weeks 12 and 24; prior null response, a decrease in the HCV RNA level of less than 2 log 10 IU/ml at week 12. The primary measure of efficacy was the rate of SVR, defined as undetectable HCV RNA at week 24 after the end of treatment. Statistical analyses Statistical analyses were conducted using SPSS Statistics 22.0 (IBM SPSS Inc., Chicago, IL, USA). Baseline continuous data are expressed as median (first-third quartiles) and categorical variables are reported as frequencies and percentages. Univariate analyses were done using the c 2, Fisher s Exact, or Mann Whitney U test as appropriate. The results are expressed as odds ratios (OR) and their 95% CIs. Receiver operating characteristic (ROC) curve analysis was done to evaluate the relationship between the fibrosis values and SVR. The cutoff values were calculated from the ROC curve to maximize the total sensitivity and specificity and we showed the values of the area under the ROC curve (AUROC). We compared the AUROCs pairwise among all ROC curves using the method described by Delong et al. [23]. A P-value less than 0.05 was regarded as statistically significant in all analyses. Results Patient characteristics The baseline characteristics of the patients are shown in Table 1. Of the 108 patients enrolled, 105 (97.2%) were infected with HCV genotype 1b and the others (only 3) were genotype 1a. The median age was 63 and 48.1% of the patients were men. Almost all (95.4%) received liver biopsy within the two weeks before the initiation of triple therapy, five did not due to being under anticoagulation therapy or as they had prolonged bleeding time: 32.0% had advanced fibrosis Table 1. Patient baseline characteristics Baseline characteristics Values Patients, n 108 Age, years 63 (52 68) Male 52 (48.1) Body mass index, kg/m ( ) Serum albumin, g/l 41 (38 43) Total bilirubin, mmol/l 15 (12 21) Aspartate aminotransferase, U/l 45 (31 78) Alanine aminotransferase, U/l 48 (28 79) g-glutamyl transpeptidase, U/l 39 (25 76) Estimated glomerular filtration rate, 81 (70 94) ml/min/1.73 m 2 a-fetoprotein, ng/ml 4.8 ( ) White blood cell count, 10 9 /l 5.1 ( ) Haemoglobin, g/l 138 ( ) Platelet count, 10 9 /l 159 ( ) HCV genotype 1a 3 (2.8) 1b 105 (97.2) HCV RNA level, log 10 IU/ml 6.5 ( ) Fibrosis stage (METAVIR score) F (59.2) F2 9 (8.7) F3 13 (12.6) F4 20 (19.4) Not determined, n 5 FibroScan, kpa 8.6 ( ) FIB-4 index 2.6 ( ) APRI 0.7 ( ) IL28B SNPs (rs ) TT 63 (58.3) TG 43 (39.8) GG 2 (1.9) Treatment-naive 31 (28.7) Treatment-experienced a Prior relapse 47 (43.5) Prior partial response 16 (14.8) Prior null response 14 (13.0) Data are expressed as n (%) or median (first third quartiles) unless otherwise indicated. a Treatment-experienced patients had received pegylated interferon-a and ribavirin dual therapy. APRI, aspartate aminotransferase to platelet ratio index; IL28B, interleukin 28B; SNP, single nucleotide polymorphism. Antiviral Therapy

4 E Ogawa et al. (F3 4). The data of FibroScan, FIB-4 index, APRI and IL28B single nucleoside polymorphism (SNP; rs ) were available for all studied patients. Correlation between fibrosis stage determined by liver biopsy (METAVIR score) and the non-invasive assessment tools The METAVIR score was significantly correlated with each non-invasive assessment tool (Additional file 1). Of them, the FibroScan value had the highest coefficient correlation value (r=0.642; P<0.0001), followed by FIB-4 index (r=0.475; P<0.0001) and APRI (r=0.474; P<0.0001). Treatment efficacy SVR was achieved by 84.3% (91 of 108) of the patients by intention-to-treat analysis. For treatment-naive patients, the SVR rate was 87.1% (27 of 31). The SVR rates of patients with prior relapse and prior partial response were 97.9% (46 of 47) and 81.3% (13 of 16), respectively. The SVR rate of patients with prior null response was notably low (35.7%, 5 of 14). Univariate analysis of the predictors of SVR is shown in Table 2. In univariate analysis of treatment-experienced patients, higher serum albumin (P=0.0031), lower AST (P=0.0335), lower a-fetoprotein (P=0.0012), higher white blood cell count (P=0.0415), higher platelet count (P=0.0077), no or mild fibrosis (P=0.0002), IL28B TT genotype (P=0.0002) and prior relapse (P<0.0001) were associated with SVR. Impact of fibrosis on the prediction of SVR from TVRbased triple therapy First, the patients were divided into treatment-naive, prior relapse, prior partial response and prior null response groups. The impact of fibrosis on SVR was greater for patients with prior partial/null response (F0 2: 88.2% [15/17], F3 4: 9.1% [1/11]), while for patients with prior relapse the stage of fibrosis had no impact on SVR (F0 2: 100% [28/28], F3 4: 94.4% [17/18]; Figure 1). Second, these groups were divided by IL28B TT and TG/GG genotype (Table 3). The impact of fibrosis on SVR was greater for patients with the IL28B TG/GG genotype (F0 2: 85.7% [24/28], F3 4: 37.5% [6/16]), while for the IL28B TT genotype the stage of fibrosis had no impact on SVR (F0 2: 97.6% [41/42], F3 4: 88.2% [15/17]). Of particular note is that none of the prior partial/null response patients with IL28B TG/GG genotype and advanced fibrosis (0/9) achieved SVR, in total contrast to the high SVR rate for prior partial/null response with IL28B TG/GG genotype and no or mild fibrosis (83.3% [10/12]). Assessment of the prediction of SVR in terms of fibrosis assessment by liver biopsy and non-invasive methods Table 4 shows the ROC curve analyses that were performed to determine the optimal threshold values of fibrosis assessment for predicting SVR, including those who had prior partial/null response. In ROC analysis of prior partial/null response, the AUROC was 0.91 and the cutoff METAVIR score was F2 (sensitivity 87.5%, specificity 91.7%, positive predictive value 93.3%, Table 2. Univariate analysis of predictors of SVR by telaprevir-based triple therapy Treatment-naive (n=31) Treatment-experienced (n=77) Parameters Odds ratio 95% CI P-value Odds ratio 95% CI P-value Age, year , , Sex, male , , Body mass index, kg/m , , Serum albumin, g/l , , Total bilirubin, mmol/l , , Aspartate aminotransferase, U/l , , Alanine aminotransferase, U/l , , g-glutamyl transpeptidase, U/l , , egfr, ml/min/1.73 m , , a-fetoprotein, ng/ml , , White blood cell count, 10 9 /l , , Haemoglobin, g/l , , Platelet count, 10 9 /l , , HCV RNA, log 10 IU/ml , , Fibrosis, F0 2 versus F , , IL28B (rs ), TT versus TG/GG , , Prior treatment response, relapse , < versus partial/null SVR, sustained virological response; egfr, estimated glomerular filtration rate; IL28B, interleukin 28B International Medical Press

5 Non-invasive fibrosis assessment in TVR-based triple therapy Figure 1. Impact of fibrosis on the prediction of SVR from telaprevir-based triple therapy F0 2 F P<0.05 P< SVR rate, % Treatment-naive Relapse Partial Null 0 SVR, sustained virological response. n Table 3. The rate of sustained virological response to telaprevir-based triple therapy classified by fibrosis stage (METAVIR) and IL28B genotype (rs ) F0 2 F3 4 TT TG/GG TT TG/GG Treatment-naive 18/19 4/6 2/3 1/1 (94.7) (75.0) (66.7) (100) Treatment-experienced Prior relapse 18/18 10/10 12/12 5/6 (100) (100) (100) (83.3) Prior partial response 4/4 6/7 1/1 0/2 (100) (85.7) (100) (0) Prior null response 1/1 4/5 0/1 0/7 (100) (80.0) (0) (0) Data are n/total n (%). IL28B, interleukin 28B. negative predictive value 84.6%). Among the noninvasive fibrosis assessment techniques, the AUROC for FibroScan value was higher than those for FIB-4 index and APRI. The AUROC for FibroScan was 0.99 and the cutoff value was 10.0 kpa (sensitivity 94.4%, specificity 100%, positive predictive value 100%, negative predictive value 92.3%). Comparing the performance of the four tests for the prediction of SVR, all values were shown to have equal, excellent diagnostic power, moreover, there was no statistically significant difference among these four AUROCs. Treatment failure The main reasons for not achieving SVR were viral breakthrough during treatment (2.8%, 3 of 108) and viral relapse after the end of treatment (13.0%, 14 of 108). Viral breakthrough occurred after week 12, therefore, none of the patients met the stop criteria. Of the three patients with viral breakthrough, two had advanced fibrosis (F3 4) and the IL28B TG genotype. Correlation between treatment adherence and SVR The treatment adherence analysis included 98 patients (90.7%) after the exclusion of 10 who discontinued treatment. The SVR rate of the patients who completed treatment was 87.8% (86 of 98). No significant Antiviral Therapy

6 E Ogawa et al. Table 4. Optimal cutoff values for the prediction of sustained virological response to telaprevir-based triple therapy in patients with prior partial/null response Fibrosis (METAVIR) FibroScan FIB-4 index APRI Cutoff value F kpa AUROC (95% CI) 0.91 (0.79, 1.00) 0.99 (0.98, 1.00) 0.91 (0.81, 1.00) 0.91 (0.79, 1.00) P-value < < < < Sensitivity, % Specificity, % Positive predictive value, % Negative predictive value, % Positive likelihood ratio 10.5 Infinity Negative likelihood ratio APRI, aspartate aminotransferase to platelet count ratio index; AUROC, area under the receiver operating characteristic curve. differences were found in the mean weight-adjusted PEG-IFN-a2b, RBV and TVR dosages of the SVR and non-svr groups. Prediction of adverse effects using fibrosis assessment Haematological and dermatological disorders were the major adverse effects to TVR-based triple therapy. A total of 47 (43.5%), 16 (14.8%) and 7 (6.5%) patients experienced severe anaemia (haemoglobin <85 g/l), neutropenia (< /l) and thrombocytopenia ( /l), respectively. Using the cutoff values noted in Table 4, the FIB-4 index was statistically useful for predicting the development of all haematological disorders (Additional file 2). Dermatological disorders of grade 2 or 3 were not related to the fibrosis status. Ten patients (9.3%) had serum albumin <35 g/l and platelet count < /l at baseline. Of them, six (60.0%) achieved SVR and none had bacterial infection, however, three (30.0%) discontinued treatment due to an adverse effect; severe fatigue, psychiatric disorder and the onset of B-cell lymphoma, respectively. Discussion The options for therapy for chronic HCV infection are changing rapidly with the introduction of DAAs. This study showed the association between SVR by TVRbased triple therapy and non-invasive fibrosis assessment, including transient elastography (FibroScan), APRI and FIB-4 index. We noted that the fibrosis stage was strongly related to the treatment outcome of patients with unfavourable conditions in terms of prior treatment outcome and IL28B genotype (rs ). As a result of the evaluation of fibrosis using the fibrosis stage by liver biopsy and non-invasive assessments, both indicated the ability to predict SVR quite effectively, showing that noninvasive assessment would be a useful alternative to the invasive and more dangerous liver biopsy. Factors associated with the likelihood of SVR to TVR-based triple therapy by both treatment-naive and -experienced patients have been assessed in clinical trials and in the clinical practice setting. Representative baseline preferable factors are no or mild fibrosis, HCV genotype 1b, IL28B favourable allele, non-black race and prior relapse to PEG-IFN-a and RBV [6 9,24]. Almost all Japanese chronic hepatitis C patients are infected with HCV genotype 1b, therefore, the essential elements of successful TVR-based triple therapy are only three: liver fibrosis stage, IL28B SNPs and prior response to PEG-IFN-a and RBV. As a matter of course, rapid virological response (undetectable HCV RNA at week 4) [6 9] and pharmacokinetic factors [25] influence SVR; moreover, it is important to take into account the treatment factors that influence the outcome, such as treatment adherence and duration. In this study, however, no significant differences were found in the mean weight-adjusted PEG-IFN-a2b, RBV or TVR dosages between SVR and non-svr groups of patients who completed treatment. From the standpoint of viral relapse, treatment adherence had little effect on the treatment outcome. In our study, almost all (over 90%) patients who had prior relapse or the IL28B TT genotype achieved SVR, irrespective of fibrosis stage. Similarly, 87.1% of treatment-naive patients achieved SVR, but the fibrosis status of most was no or mild fibrosis because the patients with advanced fibrosis had been recommended and were treated with antiviral treatment in the early stage. The important finding of this study is the low expectation of SVR for patients with advanced fibrosis and prior partial or null response: this tendency was previously shown in some clinical trials that involved Caucasian individuals [5]. We can see from the above that it is important to make efficient use of fibrosis assessment in the prediction of the treatment outcome of these difficult-to-treat patients. Liver biopsy is no longer required to assess the severity of hepatic damage caused by HCV. Non-invasive tools, including serum fibrosis markers and transient elastography, now allow rapid and accurate assessment International Medical Press

7 Non-invasive fibrosis assessment in TVR-based triple therapy of the extent of liver fibrosis [11 15]. In contrast to liver biopsies, these procedures can be repeated periodically, moreover, the APRI and FIB-4 indexes are easily accessible and the calculations are relatively simple. Using these non-invasive assessment tools, we showed the validity of predicting SVR in comparison with liver biopsy. As stated above, due to the high SVR rates in the treatment-naive and prior relapse groups, there was no additional benefit from knowledge of the fibrosis stage. On the other hand, high fibrosis stage estimated by transient elastography, FIB-4 index and APRI, as well as by liver biopsy, was strongly associated with a poor SVR rate in prior partial or null responders. Furthermore, we determined by ROC analysis the optimal cutoff values for each modality for the assessment of fibrosis that best predict SVR. Considering the results of high AUROC scores and positive/negative predictive values in all modalities, fibrosis assessment would seem to be a reasonable component in the process of selecting which prior partial or null responders can receive TVR-based triple therapy. Reports on patients with advanced fibrosis treated with the second-wave NS3/4A protease inhibitors in combination with PEG-IFN-a and RBV, with mild adverse effects in clinical trials, are still scarce. Among them, the SVR rate of F0 2 patients treated with simeprevir tended to be higher than that of F3 4 patients with prior partial (76 79% versus 15 82%) or null response (53 66% versus 22 46%) [26,27]. Therefore, in addition to prior treatment response, the non-invasive assessment of fibrosis will be a valuable option for optimizing therapy. However, IFN-free DAA regimens with or without RBV will become available for clinical use in the future and may be sufficient to achieve a virological cure, except for a tiny minority of difficultto-treat patients. It should be noted that our studied patients were mostly infected with HCV genotype 1b, rarely 1a (only three, 2.8%), and that this distribution of HCV subtypes is ordinary in Japan. Another limitation of this study was the fixed treatment duration of 24 weeks, irrespective of viral kinetics and fibrosis stage. In fact, the relapse rate of cirrhotic patients (27.8%, 5/18) was higher than that of non-cirrhotic patients (8.8%, 7/80) in this study, although cirrhotic patients often have other unfavourable conditions (for example, IL28B TG/ GG genotype or prior partial/null response). Moreover, TVR dose reduction is not recommended in most countries, but we previously showed that the TVR dosage had little effect on the treatment outcome of patients with advanced fibrosis [28]. Further examination will be required to clarify the usefulness of non-invasive fibrosis assessment in predicting SVR. In conclusion, TVR in combination with PEG-IFNa2b and RBV was quite effective for patients with prior relapse to dual therapy or IL28B TT genotype (rs ). For prior partial or null responders, the fibrosis stage was significantly associated with SVR. An alternative to METAVIR score by liver biopsy, non-invasive fibrosis assessment is a useful option for predicting SVR in this age of diversified treatment for chronic hepatitis C. Acknowledgements We are grateful to Mosaburo Kainuma, Kyoko Okada, Haru Mukae, Hiroaki Ikezaki, Satoshi Hiramine, Fujiko Mitsumoto, Koji Takayama, Norihito Sato, Sakiko Hayasaki, Kazuya Ura, Yoshifumi Kato and Masaru Sakiyama from the Department of General Internal Medicine, Kyushu University Hospital, Fukuoka, Japan for their assistance with this study. We are grateful to Yoshitaka Etoh for his excellent lab work on IL28B SNPs. Disclosure statement The authors declare no competing interests. This research received no specific funding. Additional files Additional file 1: A figure of the correlation between METAVIR score and non-invasive assessment tools is available from documents/3207_ogawa_add_file1.pdf Additional file 2: A table of the adverse effects of telaprevir-based triple therapy is available from Ogawa_Add_File2.pdf References 1. World Health Organization. WHO fact sheet 164 hepatitis C. (Accessed 14 May 2014.) Available from mediacentre/factsheets/fs164/en/ 2. Morgan TR, Ghany MG, Kim HY, et al. Outcome of sustained virological responders with histologically advanced chronic hepatitis C. Hepatology 2010; 52: van der Meer AJ, Veldt BJ, Feld JJ, et al. Association between sustained virological response and all-cause mortality among patients with chronic hepatitis C and advanced hepatic fibrosis. JAMA 2012; 308: Ogawa E, Furusyo N, Kajiwara E, et al. 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