Antiviral Therapy 2011; 16: (doi: /IMP1866)

Transcription

1 Antiviral Therapy 11; 1:915 9 (doi: 1.351/IMP1) Original article Hepatitis B surface antigen () and serum interferon-inducible protein-1 levels as predictive markers for loss during treatment with nucleoside/nucleotide analogues Jerzy Jaroszewicz 1,, Huy Ho 1, Antoaneta Markova 1, Katja Deterding 1, Karsten Wursthorn 1, Sandra Schulz 1, Claus-Thomas Bock 3, Hans L Tillmann 1,, Michael P Manns 1, Heiner Wedemeyer 1, Markus Cornberg 1 * 1 Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany Department of Infectious Diseases and Hepatology, Medical University of Bialystok, Bialystok, Poland 3 Department of Infectious Diseases, Robert Koch Institute, Berlin, Germany Duke Clinical Research Institute, GI/Hepatology Research Program, Division of Gastroenterology, Durham, NC, USA *Corresponding author Cornberg.Markus@mh-hannover.de These authors made an equal contribution to this work Background: Hepatitis B surface antigen () loss is the ultimate goal of antiviral therapy and its prediction may be important for treatment individualization. Quantitative (q) has been shown to predict response to interferon-α, but few studies have analysed q during treatment with nucleoside/nucleotide analogues (NAs). Serum interferon-inducible protein-1 (IP-1) has been associated with treatment response in hepatitis C, but data in chronic hepatitis B are lacking. Here, we aimed to investigate potential factors predictive for loss. Methods: was quantified at multiple time points in 1 patients with chronic HBV infection; 95 received NA treatment for 17 months. At an early time point (first months of therapy) and late time point after virological response (VR; HBV DNA<1 IU/ ml), we distinguished three patterns of : strong (>.5 log 1 ), moderate (1% to.5 log 1 ) and no (<1%). In addition to conventional biochemical and virological parameters, we analysed serum IP-1 levels in 55 patients. Results: Early and late kinetics did not correlate. Overall, % of patients with a strong years after VR cleared. Importantly, no patient without a late >.5 log 1 cleared. By contrast, early after months of NA therapy was not associated with loss. Baseline serum IP-1 levels were associated with late but not early kinetics and were highest in patients with loss. Conclusions: Monitoring q after successful HBV DNA suppression might be useful to identify patients who clear, implicating finite NA treatment. The role of IP-1 as predictive marker for loss should be further evaluated. Introduction Chronic HBV infection affects >35 million people worldwide. The sequels of HBV infection are cirrhosis and hepatocellular carcinoma [1,]. Effective suppression of HBV DNA with nucleoside/nucleotide analogues (NAs) has shown to delay disease progression in patients with chronic hepatitis B and reduce the development of hepatocellular carcinoma [3,]. However, treatment duration with NA is not finite and stopping rules are not clearly defined. Even after hepatitis B e antibody (anti-hbe) seroconversion, discontinuation of anti-hbv therapy is often associated with rebound of HBV and recurrence of active hepatitis [5]. Thus, hepatitis B surface antibody seroconversion is the ultimate goal of treatment [1,]. However, loss is a rare event even after long-term NA treatment [7,]. The kinetics of HBV DNA suppression do not predict hepatitis B surface antigen () [9]. Thus, no reliable marker is yet available in order to predict if patients need life-long therapy or may be treated only for a limited time with NAs. Recently, the introduction of standardized assays allowed reliable quantification of [1]. Several 11 International Medical Press (print) -5 (online) 915

2 J Jaroszewicz et al. Table 1. Baseline characteristics of NA-treated patients and comparison between patients with loss versus persistence during long-term suppression of HBV DNA Characteristic All patients (n=95) loss (n=) persistence (n=9) P-value a Median age, years (range) ( ) 5 ( 57) 5 ( 5). Male/female gender, n 7/1 5/1 9/.7 Median HBV DNA, log 1 (1 9% CI) 5.7 (3.53.) 7.5 (.95.9) 5.7 (3.53.).1 Median, log 1 (1 9% CI) 3.7 (.5.79).5 (3.77.1) 3.73 (.5.7).3 HBeAg-positive, n (%) 31 (33) (33) 9 (33).9 Genotype.51 A, n (%) (1) (33) 1 () D, n (%) 7 (9) 3 (5) (9) Other, n (%) 13 (1) () 13 (15) Not available, n (%) 15 (1) 1 (17) 1 (1) Median ALT, (1 9% CI) (33 9) 1 (95 7) 7 (33 9). Median AST, (1 9% CI) (3 3) 15 ( 3) 59 (3 31). Median GGT, (1 9% CI) 9 (17 179) 11 ( ) 9 (17 17).11 Median bilirubin, µmol/l (1 9% CI) 13 ( 3) 1. (1 95) 13.5 ( 31).7 Median platelet count, 1 3 /l (1 9% CI) 15 ( 9) 17 (3 1) 15 ( 7). Median INR (1 9% CI) 1.1 (.9 1.) 1.17 (1..3) 1.1 (1. 1.3).3 a P-value comparing patients with hepatitis B surface antigen () loss and persistence by Mann Whitney U test. ALT, alanine aminotransferase; AST, aspartate aminotransferase; GGT, γ-glutamyltransferase; HBeAg, hepatitis B e antigen; INR, International Normalized Ratio; NA, nucleoside/nucleotide analogue. studies have shown that levels vary during the natural course of HBV infection [11 1]. level below a certain cutoff may potentially differentiate between low replicative carriers and hepatitis B e antigen (HBeAg)-negative patients with active disease [11,15]. Moreover, quantification might be a valuable tool in predicting response to the interferon (IFN)-a treatment in both HBeAg-positive and HBeAg-negative hepatitis [1 19]. So far, only few studies analysed -levels during NA therapy [9, 3]. Most studies focused on early kinetics during the first 3 years of therapy. However, we will demonstrate here that kinetics might differ early during treatment when HBV DNA is still positive as compared to later patterns when suppression of HBV DNA has been achieved. Therefore, this study aimed to analyse early ( months after therapy start) as well as late of levels during therapy with various NAs after virological suppression (VR), defined as HBV DNA<1. An important objective was to assess potential factors predictive for loss, which could be applicable in anti-hbv therapy optimization. To further elucidate potential mechanism in, we analysed serum IFN-inducible protein-1 (IP-1) in 55 patients treated with NAs in our study cohort in addition to conventional biochemical and virological parameters. Serum IP-1 has been associated with response to pegylated IFN-α and ribavirin treatment in patients with chronic hepatitis C [,5]. Two studies have documented that IP-1 (IFN-γ-inducible protein of 1 kd) is a response gene induced in livers of HBV transgenic mice and chimpanzees during acute HBV infection [,7]. Methods Patients and study design Two cohorts were recruited in a single university hospital between 199. Cohort 1 comprised 95 patients receiving therapy with NAs who achieved HBV DNA suppression <1 (that is, virological response [VR]) during the follow-up period without occurrence of virological breakthrough. Follow-up period ranged from 17 months (Table 1). Anti-HBV treatment regimens included lamivudine (3TC, n=9), entecavir (ETV, n=), adefovir (ADV, n=1), 3TC plus ADV (n=19), tenofovir (TDF) (n=9) and other treatments (telbivudine and famciclovir, n=). Serum -levels were quantified and analysed at baseline, months after start of the therapy, at the first time point of VR and on a yearly basis thereafter. was analysed between baseline and months (early, n=95) and during years after reaching VR (late, n=). A representative example is shown in Figure 1A. A second cohort consisted of 31 patients (15 male, aged 1 years) not undergoing anti-hbv therapy, mainly due to low HBV DNA and/or no evidence for hepatitis. This group was followed-up for 3 months. was quantified at least once a year. None of the individuals included in the study had hepatitis delta virus, HCV or HIV coinfection International Medical Press

3 and IP-1 during NA therapy Figure 1. during treatment with NAs A, log 1 1 Early Late HBV DNA B, log 1 1 Early Late BL TM VR 1 year years C 1 3 years Early Late BL TM VR 1 year years 3 years, log 1 Potent NA Less potent NA BL TM VR 1 year years 3 years (A) Hepatitis B surface antigen () during nucleoside/nucleotide analogue (NA) treatment was analysed between baseline (BL) and treatment month (TM; early ) and during the first years after achieving virological response (VR; late ). The graph depicts an individual case during adefovir therapy. (B) Median in patients during NA therapy over the period of 3 years after reaching VR (.1 log 1 ). (C) Median during treatment with potent NAs (tenofovir and entecavir; n=33) versus less potent NA (lamivudine and adefovir; n=). Serum quantification Serum -levels were quantified using the Abbott ARCHITECT assay (dynamic range of.5 5 IU/ ml; Abbott Diagnostics, Abbott Park, IL, USA). Samples were diluted 1:1 in horse serum and, if >5 IU/ ml, samples were retested at a dilution of 1:5 and 1:1. Samples with levels <.5 have been retested without prior dilution [1]. The inter- and intra-assay variability is approximately 1% (range.7.%), according to the manufacturer datasheet. HBV DNA measurement and HBV genotyping HBV DNA was quantified with COBAS AmpliPrep/ COBAS TaqMan (Roche Diagnostics, Mannheim, Germany) with a lower limit of detection of 1 IU/ ml. Some samples were measured with Diagen Hybrid Capture II (Diagen, Hilden, Germany) with a lower limit of detection of.5 pg/ml (until 3). Samples with <.5 pg/ml have been retested with the COBAS system. We defined HBV DNA values <1 as VR. HBV genotyping was performed as previously described in detail [11]. Measurement of serum interferon-inducible protein-1 Serum concentrations of IP-1 (also known as chemokine [C-X-C motif] ligand 1), were assessed in patients using the Cytometric Bead Array assay (BD Biosciences, Heidelberg, Germany) according to the manufacturer s protocol. Serum samples from 55 patients were analysed at baseline and at the time point of VR. In addition, Antiviral Therapy

4 J Jaroszewicz et al. Table. Clinical and epidemiological description of individual cases with loss during nucleotide/nucleoside therapy Patient number Variable Age, years Gender M M F M M M Time between HBV diagnosis and therapy start, years HBeAg status Negative Positive Positive Negative Negative Negative HBV genotype D D D A A ND Baseline HBV DNA, log Baseline, log Baseline ALT, Anti-HBV therapy 3TC 3TC+ADV 3TC+ADV 3TC 3TC ETV -Month after baseline, log Month after VR, log NA Baseline IP-1, pg/ml Peak IP-1, pg/ml Time to loss, months Anti-HBs seroconversion No Yes Yes No Yes Yes ADV, adefovir; ALT, alanine aminotransferase; anti-hbs, hepatitis B surface antibody; ETV, entecavir; F, female; HBeAg, hepatitis B e antigen;, hepatitis B surface antigen; IP-1, interferon-inducible protein-1; M, male; NA, not available; ND, not done; VR, virological response; 3TC, lamivudine. we measured IP-1 longitudinally in all patients with loss (up to eight time points). Sample acquisition was performed by use of BD FACS Canto II (BD Biosciences) and analysed with FCAP Array (SoftFlow, St. Louis Park, MN, USA). This retrospective study was conducted in accordance with the guidelines of the Declaration of Helsinki, the principles of Good Clinical Practice and according to standards of the local ethics committee. The immunological substudy was part of a protocol that was approved by the local ethics committee. Statistical analyses Serum and HBV DNA levels were logarithmically transformed. Data are presented as medians (1 9% CIs), unless indicated. Non-parametric (distributionfree) tests were applied. Mann Whitney U and Kruskall Wallis ANOVA tests were used for univariate and multivariate comparisons of independent continuous variables, Friedman ANOVA was used for multivariate comparisons of dependent variables, and Fisher s exact test for discrete variables comparison. Statistical analyses were performed by use of Statistica 9. (StatSoft, Tulsa, OK, USA). Receiver operating characteristic curves and area under the curve for the prediction of loss by as well serum IP-1 levels were calculated and plotted with GraphPad Prism 5. (GraphPad Software, Inc., La Jolla, CA, USA). Results We studied the long-term kinetics in 95 subjects undergoing successful therapy with various NAs (Table 1). The median was.1 log 1 from baseline to 3 years after patients achieved VR (Figure 1B). Characteristics of patients with loss Overall, (.3%) patients lost after median duration of months (range 17 17) of continuous NA treatment. Patients who experienced treatmentinduced loss had higher baseline alanine aminotransferase (ALT; 1 versus 7, P=.; Table 1) and levels (.5 versus 3.73 log 1 IU/ ml, P=.3) than individuals with persistence (Table 1). Age and gender, as well as HBV genotype and HBeAg status were comparable. The detailed, individual characteristics of the patients with loss are provided in Table. The effect of viral factors and treatment regimen on In this study, treatment-induced HBeAg loss occurred in 1 of 31 (3.7%) HBeAg-positive patients. Overall, levels in patients who lost HBeAg d significantly during the follow-up period of 3 years after VR by contrast with patients without HBeAg loss (median 1. log 1 versus. log 1 ; Friedmann ANOVA P<.5 versus P=.3). In 5/1 patients, we detected levels >1, 1 months after anti-hbe seroconversion. Patients who were HBeAgnegative at baseline showed a median of.71 log 1 during this follow-up period. Analysing q in patients infected with HBV genotype A versus D, there tended to be a faster during the first months of therapy in HBV genotype A patients (.31 log 1 versus.1 log 1 ), but International Medical Press

5 and IP-1 during NA therapy this was not statically significant (P=.33). Patients with HBV genotype A had higher baseline levels consistent with previous data []. Overall, we did not observe a difference of between HBV genotypes during a follow-up of years after VR (HBV genotype A.73 versus HBV genotype D.3 log 1 ; P=.3). kinetics did not differ significantly between different NA regimens. The low number of patients in some of the treatment regimen did not allow for an adequate comparison of all regimens. Analysing potent antiviral NAs (ETV and TDF, n=33) versus less potent NAs (3TC and ADV, n=), we observed no significant different during the follow-up of 3 years after VR (Figure 1C). Early and late during therapy Early was analysed during the first months of NA therapy (Figure A C). Patients were divided into three groups: >.5 log 1 (group I), 1%.5 log 1 (group II) and <1% after months (group III; Figure and Table ). The non- category of <1% resulted from the data on variability of the assay. The.5 log 1 cutoff was chosen because it was associated with response to IFN therapy [17]. Three of six patients who lost showed an early (group I). However, patients in groups II and III also acheived loss, indicating failure to achieve >.5 log 1 after months does not impede later clearance (P=.3; Figure ). Next, we analysed the level of during years after VR (continuous suppression of HBV DNA<1 ) during NA therapy (Figure D F). The rationale for this approach was to evaluate dynamics without the potential interference from varying levels of HBV DNA. A total of patients were eligible for this analysis. Patients were divided into three groups based on the level of in this -year period: >.5 log 1 IU/ ml (group A), 1%.5 log 1 (group B) and <1% (group C; Figure D F and Table ). Overall, % of patients in group A cleared, whereas no patient in groups B and C developed loss (Figure ). Early and late patterns were not significantly associated (P=.39). Serum IP-1 concentrations Serum IP-1 was analysed in patients with >.5 log 1 after HBV DNA had dropped to <1 (group A) and compared to those with <.5 log 1 (groups B and C). In a cross-sectional analysis, we observed significant higher serum IP-1 levels in group A compared to group B or C patients at baseline and at the time point of VR. Interestingly, IP-1 levels were not statistically different at any time point between patients with or without early >.5 log 1 (Figure 3A). We further analysed serum IP-1 levels longitudinally in all six patients with loss. Serum IP-1 levels showed fluctuations with a peak before or at the same time started to. Some patients had not achieved their peak IP-1 levels at baseline (Table ). Median peak of IP-1 in patients with loss was 59.1 pg/ml. Analysing negative and positive predictive values for different baseline IP-1 levels, we identified a cutoff of 35 pg/ml. Figure 3B depicts the mean in patients with higher or lower baseline IP-1 levels than 35 pg/ ml (mean late 1.1 versus.1, respectively; P=.1). in the natural course of chronic HBV infection kinetics during antiviral therapy was compared with the natural dynamics in 31 patients not receiving anti-hbv therapy. Therapy was not introduced mainly due to low replication of HBV (75%) and/or no evidence for hepatitis (1%). The other patients had treatment indication, but were not treated during the observation period. Patients were followed for 3 months. The patients had baseline levels (median.1 log 1, 1 9% CI.3.1) and HBeAg distribution (3% HBeAg-positive) comparable with the NA-treated cohort (P=.7 and P=.1, respectively). dynamics were categorized according to the same criteria as for patients on therapy (groups N1, N and N3). During years of follow-up, (19%) achieved >.5 log 1 of (N1), 17 (55%) had 1%.5 log 1 (N), whereas (%) patients showed <1% change from baseline (N3). Interestingly, the distribution of groups N1 N3 was similar to groups I III and A C during NA therapy. Moreover, the ratio of patients within the same category was also similar during further follow-up (after 3 months), with % in N1, % in N and 7% in N3. One patient, a 55-year-old HBeAg-negative male, developed loss during the natural course of HBV infection. Discussion loss is the ultimate goal of anti-hbv treatment [1,,]. NAs are highly effective in suppression of HBV DNA, but loss occurs only in a minority of patients during long-term therapy [7,,9]. may in the long-term [1], but it remains unclear how long patients need to be successfully treated until loss is achieved and which factors are associated with loss. Antiviral Therapy

6 J Jaroszewicz et al. Figure. Individual kinetics during NA treatment A 1 Group I B 1 Group II, log 1, log 1 BL TM VR Y Y Y BL TM VR Y Y Y C D 1 Group A 1 Group III, log 1, log 1 BL TM VR Y Y Y BL TM VR Y Y Y E 1 Group B F 1 Group C, log 1, log 1 BL TM VR Y Y Y BL TM VR Y Y Y (A C) Patients with (A) >.5 log 1 (B) 1%.5 log 1 and (C) <1% hepatitis B surface antigen () after months. Group I: 5% of patients, % hepatitis B e antigen [HBeAg]-positive and median 1. log 1. Group II: % of patients, 9% HBeAg-positive and median.1 log 1. Group III: 31% of patients, 31% HBeAg-positive, median -.1 log 1. (D F) Patients with (D) >.5 log 1, (E) 1%.5 log 1 and (F) <1% decease years (Y) after virological response (VR; late ). Group A: 19% of patients, 5% HBeAg-positive and median. log 1. Group B: 53% of patients, 3% HBeAg-positive and median.1 log 1. Group C: % of patients, 37% HBeAg-positive and median -.5 log 1. BL, baseline; TM, treatment month International Medical Press

7 and IP-1 during NA therapy Figure 3. Association of serum interferon-inducible protein-1 levels and A Baseline P=.5 IP-1, pg/ml, 1, 1,. P= IP-1, pg/ml 9.5, 1, 1, 15. A B and C n=11 n= I II and III n=15 n= Virological response IP-1, pg/ml, 1, 1, 1. P= IP-1, pg/ml, 1, 1, 1.1 P= A B and C n=11 n= I II and III n=15 n= B 5, log 1 3 n=3 n=1 >35 pg/ml <35 pg/ml 1 BL TM VR 1 Year Years (A) Concentration of serum interferon-inducible protein-1 (IP-1) at baseline (BL) and at the time point of virological response (VR) in patients with late >.5 log 1 IU/ ml hepatitis B surface antigen () (group A) versus.5 log 1 (groups B and C); and in patients with early >.5 log 1 (group I) versus.5 log 1 (groups II and III). Median values of IP-1 are shown. (B) Mean (±sem) in patients with >35 pg/ml versus <35 pg/ml (n=3) serum IP-1 at BL. TM, treatment month. Antiviral Therapy 1. 91

8 J Jaroszewicz et al. Thus, we aimed to identify predictive factors for loss during and before NA therapy; in particular, we investigated the role of quantitative kinetics in 95 patients who were treated with different NAs over a period of 17 months. We here show that early of months after the start of NA therapy does not correlate with late and later loss; late during years after VR was associated with loss; and patients with stronger late during NA therapy had significant higher serum IP-1 concentrations. The frequency of loss in this real-world setting with different NA regimens of.3% within a median time of months is well in line with data on loss during NA therapy in pivotal trials [7,,9]. Patients with loss had higher ALT levels prior to treatment (Table 1) suggesting ongoing enhanced immune responses that eventually control HBV. This is supported by our data on serum IP-1 levels, which were significantly higher in patients with >.5 log 1 after VR (Figure 3). IP-1 has been shown to correlate with a more active disease in HBV infection [3] and with hepatic inflammation in patients with chronic hepatitis C []. However, high IP-1 levels were predictive for non-response to antiviral therapy in patients with chronic HCV infection [,5]. This may be explained by a maximally activated endogenous IFN system, reflected by high expression of IFN-stimulated genes, which is not able to clear HCV but may the response to treatment with exogenous IFN-α [31]. It has been demonstrated in a chimeric mouse system that HBV impairs the response to IFN-α via inhibition of STAT-1 in human hepatocytes. The same study also documented slightly increased IFN-stimulated gene expression in HBV-infected livers [3]. The higher IP-1 level in our study may reflect an activated IFN system. However, in patients with chronic hepatitis B, an activated IFN system may be beneficial if the patient is in an earlier phase of HBV infection and/or viraemia is suppressed long-term with direct antiviral agents. Surprisingly, levels and HBV DNA levels were not lower, but were higher in patients with subsequent loss, although high antigenic load is associated with dysfunction of various immune cells [33 35]. Higher pretreatment levels were also associated with loss in recent Phase III trials with telbivudine and TDF [9,3]. Other groups, in addition to ours, recently showed that is correlated with the phase of HBV infection [11 1] and higher levels may therefore reflect an earlier more active stage of HBV infection as supported by ALT and IP-1 levels. Previous studies investigated mainly pretreatment factors in order to predict loss during NA therapy [1], focused on special patient populations such as transplant patients [] or included a small number of patients []. The role of dynamics has not been considered in detail thus far. We initially anticipated differences in early dynamics during therapy with NA versus late kinetics when patients achieved VR. The predictive value of in these different phases of NA therapy for subsequent loss was unknown. By contrast to IFN-based treatment [1 19], early during the first months of NA therapy was neither associated with later loss nor with delayed after HBV DNA suppression. This data further emphasizes the different mode of action between IFN and NA. Some patients with early during NA therapy might have simply changed the phase of HBV infection (that is, transition from immune clearance phase to HBeAgnegative hepatitis), which is associated with q [11 13]. We might detect an already ongoing natural in some NA-treated patients, as one patient with loss already had a 1 log 1 before the start of lamivudine therapy (5.3 log 1 1 months before baseline;.3 log 1 at baseline; JJ et al., data not shown). Thus, early kinetics alone may not reliably predict later loss. Nevertheless, a recent analysis of kinetics during treatment of HBeAg-positive patients with telbivudine suggested that strong of >1 log 1 within the first months of therapy was predictive of later loss [9], but pretreatment levels have not been studied. Moreover, telbivudine might have some immunmodulatory effects [3]. Only one patient received telbivudine treatment in our study. Because early during NA treatment was not associated with loss, we wondered if later after HBV DNA suppression (VR) might correlate with subsequent loss. Indeed, % of patients with >.5 log 1 reduction of years after VR achieved loss, whereas no patient with <.5 log 1 cleared (negative predictive value 1%). Late was not associated with the applied treatment regimen (potent versus less potent NA) further supporting our data that the initial HBV DNA suppression has a limited effect on the overall. Based on these data, we suggest that successful HBV DNA suppression may yet be the first important prerequisite for loss, as kinetics after HBV DNA suppression was predictive. However, immune modulation as suggested by our data on ALT and IP-1 may play a key role for and later loss. When HBV DNA is significantly suppressed, some patients may reconstitute the immune response leading to subsequent. Some investigators have shown immune reconstitution during NA therapy [9,37]. However, this might only be transient and T-cell exhaustion is generally difficult to overcome if HBV is established for a long time 9 11 International Medical Press

9 and IP-1 during NA therapy [3]. Thus, NA-induced loss remains infrequent. Serum IP-1 may help to identify those patients. Interestingly, the proportion of patients with strong years after achieving HBV DNA suppression during NA therapy was also not very different in the cohort of our patients during the natural course of HBV infection, again emphasizing the limited effect of NA treatment on. Still, those 19% with >.5 log 1 years after HBV DNA suppression may be candidates for a finite NA therapy. It may even be possible to terminate NA therapy before loss when a certain cutoff is reached. Studies are needed to define a cutoff for a sustained immune control. Based on previous data during the natural course, immune control may be indicated by low levels (<1, ) [15]. It will be valuable if other markers could predict loss or sustained immune control. We suggest that serum IP-1 may be a diagnostic tool that can help to discriminate patients with response to NA therapy and further improve the positive predictive value for q (baseline IP-1>35 pg/ml plus >.5 log 1 after VR; positive predictive value 57% for loss). In conclusion, during NA treatment is generally weak and during the first months of NA therapy was not predictive for loss, which is in contrast to IFN-based therapies. Patients who received no treatment demonstrated comparable kinetics during the natural course of HBV infection. These data suggest that NA therapy may have only a limited effect on suppression per se, explaining that remains a rare event during NA therapy. Thus, most patients treated with NA will require life-long therapy. Nevertheless, about 1/5 of NA-treated patients achieve significant years after HBV DNA suppression, which is associated with loss. Monitoring q, particularly after HBV DNA is suppressed, could identify patients who might be candidates for a finite treatment. Our data on IP-1 also suggest that significant and later loss may be limited to patients with stronger immune responses. Further studies should investigate the role of IP-1 as predictive marker for loss in patients with chronic hepatitis B. Acknowledgements We thank Regina Raupach and Birgit Bremer for technical assistance. Disclosure statement JJ received lecture fees from Roche. KD received lectural fees and/or travel support from Gilead and BMS. KW received lectural fees and/or travel support from Gilead, Novartis and BMS. C-TB received grants and/or lecture fees from Gilead and BMS. HLT received consult/lecture fees from Novartis and Roche. HLT s spouse is an Abbott Laboratories employee, who also holds stock in Abbott. MPM received grants, lecture fees and/or consult fees from GSK, Gilead, Novartis, BMS, Roche and Abbott. HW received grants, lecture fees and/or consult fees from Gilead, Novartis, BMS, Roche and Abbott. MC received lecture fees and/or consult fees from Gilead, Novartis, Roche and BMS. All other authors declare no competing interests. References 1. EASL Clinical Practice Guidelines. Management of chronic hepatitis B. J Hepatol 9; 5:7.. Ganem D, Prince AM. Hepatitis B virus infection natural history and clinical consequences. N Engl J Med ; 35: Liaw YF, Sung JJ, Chow WC, et al. Lamivudine for patients with chronic hepatitis B and advanced liver disease. N Engl J Med ; 351: Papatheodoridis GV, Lampertico P, Manolakopoulos S, Lok A. Incidence of hepatocellular carcinoma in chronic hepatitis B patients receiving nucleos(t)ide therapy: a systematic review. J Hepatol 1; 53: Reijnders JG, Perquin MJ, Zhang N, Hansen BE, Janssen HL. Nucleos(t)ide analogues only induce temporary hepatitis B e antigen seroconversion in most patients with chronic hepatitis B. Gastroenterology 1; 139: Cornberg M, Protzer U, Dollinger MM, et al. Prophylaxis, diagnosis and therapy of hepatitis B virus (HBV) infection: the German guidelines for the management of HBV infection. Z Gastroenterol 7; 5: Gish RG, Chang TT, Lai CL, et al. Loss of antigen during treatment with entecavir or lamivudine in nucleoside-naive HBeAg-positive patients with chronic hepatitis B. J Viral Hepat 1; 17:1.. Marcellin P, Chang TT, Lim SG, et al. Long-term efficacy and safety of adefovir dipivoxil for the treatment of hepatitis B e antigen-positive chronic hepatitis B. Hepatology ; : Wursthorn K, Jung M, Riva A, et al. Kinetics of hepatitis B surface antigen decline during 3 years of telbivudine treatment in hepatitis B e antigen-positive patients. Hepatology 1; 5: Wursthorn K, Jaroszewicz J, Zacher BJ, et al. Correlation between the Elecsys II assay and the Architect assay for the quantification of hepatitis B surface antigen () in the serum. J Clin Virol 11; 5: Jaroszewicz J, Calle Serrano B, Wursthorn K, et al. Hepatitis B surface antigen () levels in the natural history of hepatitis B virus (HBV)-infection: a European perspective. J Hepatol 1; 5: Nguyen T, Thompson AJ, Bowden S, et al. Hepatitis B surface antigen levels during the natural history of chronic hepatitis B: a perspective on Asia. J Hepatol 1; 5: Chan HL, Wong VW, Wong GL, Tse CH, Chan HY, Sung JJ. A longitudinal study on the natural history of serum hepatitis B surface antigen changes in chronic hepatitis B. Hepatology 1; 5: Thompson AJ, Nguyen T, Iser D, et al. Serum hepatitis B surface antigen and hepatitis B e antigen titers: disease phase influences correlation with viral load and intrahepatic hepatitis B virus markers. Hepatology 1; 51: Brunetto MR, Oliveri F, Colombatto P, et al. Hepatitis B surface antigen serum levels help to distinguish active from inactive hepatitis B virus genotype D carriers. Gastroenterology 1; 139:3 9. Antiviral Therapy 1. 93

10 J Jaroszewicz et al. 1. Brunetto MR, Moriconi F, Bonino F, et al. Hepatitis B virus surface antigen levels: a guide to sustained response to peginterferon alfa-a in HBeAg-negative chronic hepatitis B. Hepatology 9; 9: Moucari R, Mackiewicz V, Lada O, et al. Early serum drop: a strong predictor of sustained virological response to pegylated interferon alfa-a in HBeAg-negative patients. Hepatology 9; 9: Sonneveld MJ, Rijckborst V, Boucher CA, Hansen BE, Janssen HL. Prediction of sustained response to peginterferon alfa-b for hepatitis B e antigen-positive chronic hepatitis B using on-treatment hepatitis B surface antigen decline. Hepatology 1; 5: Rijckborst V, Hansen BE, Cakaloglu Y, et al. Early on-treatment prediction of response to peginterferon alfa-a for HBeAg-negative chronic hepatitis B using and HBV DNA levels. Hepatology 1; 5:5 1.. Wiegand J, Wedemeyer H, Finger A, et al. A decline in hepatitis B virus surface antigen () predicts clearance, but does not correlate with quantitative HBeAg or HBV DNA levels. Antivir Ther ; 13: Borgniet O, Parvaz P, Bouix C, et al. Clearance of serum and anti-hbs seroconversion following antiviral therapy for chronic hepatitis B. J Med Virol 9; 1: Manesis EK, Hadziyannis ES, Angelopoulou OP, Hadziyannis SJ. Prediction of treatment-related loss in HBeAg-negative chronic hepatitis B: a clue from serum levels. Antivir Ther 7; 1: Heathcote EJ, Marcellin P, Buti M, et al. Three-year efficacy and safety of tenofovir disoproxil fumarate treatment for chronic hepatitis B. Gastroenterology 11; 1: Reiberger T, Aberle JH, Kundi M, et al. IP-1 correlates with hepatitis C viral load, hepatic inflammation and fibrosis and predicts hepatitis C virus relapse or nonresponse in HIV HCV coinfection. Antivir Ther ; 13: Darling JM, Aerssens J, Fanning G, et al. Quantitation of pretreatment serum interferon-gamma-inducible protein-1 improves the predictive value of an ILB gene polymorphism for hepatitis C treatment response. Hepatology 11; 53:1.. Kakimi K, Lane TE, Wieland S, et al. Blocking chemokine responsive to gamma-/interferon (IFN)-gamma inducible protein and monokine induced by IFN-gamma activity in vivo reduces the pathogenetic but not the antiviral potential of hepatitis B virus-specific cytotoxic T lymphocytes. J Exp Med 1; 19: Accepted 1 May 11; published online July Wieland S, Thimme R, Purcell RH, Chisari FV. Genomic analysis of the host response to hepatitis B virus infection. Proc Natl Acad Sci U S A ; 11:9 7.. Cornberg M, Jaroszewicz J, Manns MP, Wedemeyer H. Treatment of chronic hepatitis B. Minerva Gastroenterol Dietol 1; 5: Chang TT, Lai CL, Kew Yoon S, et al. Entecavir treatment for up to 5 years in patients with hepatitis B e antigenpositive chronic hepatitis B. Hepatology 1; 51: Deng G, Zhou G, Zhang R, et al. Regulatory polymorphisms in the promoter of CXCL1 gene and disease progression in male hepatitis B virus carriers. Gastroenterology ; 13: Sarasin-Filipowicz M, Oakeley EJ, Duong FH, et al. Interferon signaling and treatment outcome in chronic hepatitis C. Proc Natl Acad Sci U S A ; 15: Lütgehetmann M, Bornscheuer T, Volz T, et al. Hepatitis B virus limits response of human hepatocytes to interferon-alpha in chimeric mice. Gastroenterology 11; 1: Mueller SN, Ahmed R. High antigen levels are the cause of T cell exhaustion during chronic viral infection. Proc Natl Acad Sci U S A 9; 1:3. 3. Op den Brouw ML, Binda RS, van Roosmalen MH, et al. Hepatitis B virus surface antigen impairs myeloid dendritic cell function: a possible immune escape mechanism of hepatitis B virus. Immunology 9; 1: Reignat S, Webster GJ, Brown D, et al. Escaping high viral load exhaustion: CD cells with altered tetramer binding in chronic hepatitis B virus infection. J Exp Med ; 195: Wu ZG, Yan WM, Guo W, et al. Telbivudine preserves T-helper 1 cytokine production and downregulates programmed death ligand 1 in a mouse model of viral hepatitis. J Viral Hepat 1; 17 Suppl 1: Boni C, Bertoletti A, Penna A, et al. Lamivudine treatment can restore T cell responsiveness in chronic hepatitis B. J Clin Invest 199; 1: Boni C, Penna A, Bertoletti A, et al. Transient restoration of anti-viral T cell responses induced by lamivudine therapy in chronic hepatitis B. J Hepatol 3; 39: International Medical Press