A. Markova

Eligibility and Safety of Triple Therapy for Hepatitis C: Lessons Learned from the First Experience in a Real World Setting

Background HCV protease inhibitors (PIs) boceprevir and telaprevir in combination with PEG-Interferon alfa and Ribavirin (P/R) is the new standard of care in the treatment of chronic HCV genotype 1 (GT1) infection. However, not every HCV GT1 infected patient is eligible for P/R/PI therapy. Furthermore phase III studies did not necessarily reflect real world as patients with advanced liver disease or comorbidities were underrepresented. The aim of our study was to analyze the eligibility and safety of P/R/PI treatment in a real world setting of a tertiary referral center. Methods All consecutive HCV GT1 infected patients who were referred to our hepatitis treatment unit between June and November 2011 were included. Patients were evaluated for P/R/PI according to their individual risk/benefit ratio based on 4 factors: Treatment-associated safety concerns, chance for SVR, treatment urgency and nonmedical patient related reasons. On treatment data were analyzed until week 12. Results 208 patients were included (F3/F4 64%, mean platelet count 169/nl, 40% treatment-naïve). Treatment was not initiated in 103 patients most frequently due to safety concerns. 19 patients were treated in phase II/III trials or by local centers and a triple therapy concept was initiated at our unit in 86 patients. Hospitalization was required in 16 patients; one patient died due to a gastrointestinal infection possibly related to treatment. A platelet count of <110/nl was associated with hospitalization as well as treatment failure. Overall, 128 patients were either not eligible for therapy or experienced a treatment failure at week 12. Conclusions P/R/PI therapies are complex, time-consuming and sometimes dangerous in a real world setting, especially in patients with advanced liver disease. A careful patient selection plays a crucial role to improve safety of PI based therapies. A significant number of patients are not eligible for P/R/PI, emphasizing the need for alternative therapeutic options.

Hepatitis E virus (HEV)‐specific T‐cell responses are associated with control of HEV infection

Hepatitis E virus (HEV) infection is usually self‐limited but may lead to acute hepatitis and rarely to fulminant hepatic failure. Persistent HEV infections have recently been described in organ transplant recipients receiving immunosuppressive medications, suggesting that HEV is controlled by adaptive immune responses. However, only few studies have investigated HEV‐specific T‐cell responses and immune correlates for the failure to clear HEV infection have not been established so far. We investigated T‐cell responses against HEV in 38 subjects including anti‐HEV‐positive (exposed, n = 9) and anti‐HEV‐negative (n = 10) healthy controls, 12 anti‐HEV‐positive but HEV RNA‐negative organ transplant recipients, and seven transplant recipients with chronic hepatitis E. Proliferation as well as cytokine production of CD4+ and CD8+ T cells was studied after stimulation with overlapping peptides spanning all proteins encoded by HEV‐open reading frame (ORF)2 and HEV‐ORF3. We show that (1) strong and multispecific HEV‐specific T‐cell responses are present in exposed healthy controls, and to a lesser extent also in recovered patients after transplantation; (2) that these responses are absent in patients with chronic hepatitis E but become detectable after viral clearance; and (3) that HEV‐specific T‐cell responses can be restored in vitro by blocking the PD‐1 or CTLA‐4 pathways. However, a combination of PD‐1 and CTLA‐4 blockade had no synergistic effects. We conclude that chronic hepatitis E is associated with impaired HEV‐specific T‐cell responses and suggest that enhancing adaptive cellular immunity against HEV might prevent persistent HEV infections. (HEPATOLOGY 2012)

Hepatitis B surface antigen (HBsAg) decrease and serum interferon-inducible protein-10 levels as predictive markers for HBsAg loss during treatment with nucleoside/nucleotide analogues.

BACKGROUND Hepatitis B surface antigen (HBsAg) loss is the ultimate goal of antiviral therapy and its prediction may be important for treatment individualization. Quantitative HBsAg (qHBsAg) has been shown to predict response to interferon-α, but few studies have analysed qHBsAg during treatment with nucleoside/nucleotide analogues (NAs). Serum interferon-inducible protein-10 (IP-10) 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 HBsAg loss. METHODS HBsAg was quantified at multiple time points in 126 patients with chronic HBV infection; 95 received NA treatment for 6-107 months. At an early time point (first 6 months of therapy) and late time point after virological response (VR; HBV DNA<100 IU/ml), we distinguished three patterns of HBsAg decrease: strong decrease (>0.5 log(10)), moderate decrease (10% to 0.5 log(10)) and no decrease (<10%). In addition to conventional biochemical and virological parameters, we analysed serum IP-10 levels in 55 patients. RESULTS Early and late HBsAg kinetics did not correlate. Overall, 42% of patients with a strong HBsAg decrease 2 years after VR cleared HBsAg. Importantly, no patient without a late HBsAg decrease >0.5 log(10) cleared HBsAg. By contrast, early HBsAg decrease after 6 months of NA therapy was not associated with HBsAg loss. Baseline serum IP-10 levels were associated with late but not early HBsAg kinetics and were highest in patients with HBsAg loss. CONCLUSIONS Monitoring qHBsAg after successful HBV DNA suppression might be useful to identify patients who clear HBsAg, implicating finite NA treatment. The role of IP-10 as predictive marker for HBsAg loss should be further evaluated.

Compromised Function of Natural Killer Cells in Acute and Chronic Viral Hepatitis

BACKGROUND  Natural killer (NK) cells are an integral part of the innate immune system. They have been suggested to play an important role in both defense against viral hepatitis and the pathogenesis of other liver diseases. METHODS  NK cells from 134 individuals including patients with acute hepatitis B and C as well as chronic hepatitis B, C, and delta (D) patients were studied. RESULTS  Infection with viral hepatitis was associated with increased frequencies of NK cells in the peripheral blood; that NK cells showed a less activated phenotype and were compromised in cytolotytic function and cytokine production in all viral hepatitis infections: Hepatitis virus infections did not alter NK cell differentiation, and the activity and severity of liver disease were reflected by alterations of NK cell surface receptors as demonstrated by principal component analysis. CONCLUSION  NK cell phenotypic and functional alterations can equally be observed in HBV, HCV, and HDV infections. Instead, patterns of NK cell alterations differ in acute and chronic infections. Thus, our data suggest a common mechanism in the alteration of NK cell phenotype and function with unique variations that depend on disease activity rather than virus-specific factors.

Phase III results of Boceprevir in treatment naïve patients with chronic hepatitis C genotype 1.

Chronic hepatitis C virus infection affects approximately 2% of the world population and can result in cirrhosis and hepatocellular carcinoma. Until 2011, the standard of care (SOC) has been therapy with pegylated interferon alfa and ribavirin (PEG‐IFN/RBV). Sustained virologic response rates (SVR) after SOC in patients infected with genotype 1 have been 40–50%. The development of new direct antiviral agents (DAA) is vital. The first drugs that specifically target the HCV protease have been approved in 2011. This review summarizes the results of SPRINT‐2, a phase III double blind, placebo controlled study in which the efficacy and safety of Boceprevir, a new HCV protease inhibitor, was compared to SOC.

Limited effectiveness and safety profile of protease inhibitor-based triple therapy against chronic hepatitis C in a real-world cohort with a high proportion of advanced liver disease

Background/objective Triple therapy with pegylated-interferon-&agr;, ribavirin, and a protease inhibitor (PI), boceprevir or telaprevir, is the standard of care for the treatment of chronic hepatitis C genotype 1 in several countries. Pivotal studies showed reasonable results for safety and efficacy. However, it remains uncertain to what extent this can be transferred to the real world. Here, we aimed to analyze the effectiveness and safety of pegylated-interferon-&agr;/ribavirin/PI triple therapy in a real-world cohort of a tertiary referral center. Patients and methods Between June 2011 and November 2011, a total of 208 consecutive patients with chronic hepatitis C genotype 1 were evaluated for the initiation of a triple-therapy regimen and included in this study. Eighty-six patients (86% F3/F4) started a triple-therapy regimen and were followed until 12 weeks after the end of treatment. Results Overall, 36 out of the 86 treated patients (42%) achieved a sustained virological response. However, only 17% of the initially screened 208 patients were cured with triple therapy at our center. A high rate of serious adverse events (28%) was documented during treatment. The risk/benefit ratio was poor for patients with signs of advanced liver cirrhosis (n=33, 38%), indicated by increased bilirubin, low albumin, and/or low platelet count at baseline. Conclusion The effectiveness and safety of PI-based triple therapy can be limited in real-world cohorts including large numbers of patients with advanced liver disease. Future therapies can only overcome these limitations if interferon-free regimens are established.

The clinical significance of drug-drug interactions in the era of direct-acting anti-viral agents against chronic hepatitis C.

Drug–drug interactions (DDIs) in the treatment of chronic hepatitis C infection became a potential challenge with the introduction of direct‐acting anti‐virals (DAAs). Both currently approved DAAs, the protease inhibitors (PIs) telaprevir (TVR) and boceprevir (BOC), are substrates and inhibitors of P‐glycoprotein and the cytochrome P450 3A4, which are regularly involved in DDIs.

PEG-IFN Alpha but Not Ribavirin Alters NK Cell Phenotype and Function in Patients with Chronic Hepatitis C

Background Ribavirin (RBV) remains part of several interferon-free treatment strategies even though its mechanisms of action are still not fully understood. One hypothesis is that RBV increases responsiveness to type I interferons. Pegylated Interferon alpha (PEG-IFNa) has recently been shown to alter natural killer (NK) cell function possibly contributing to control of hepatitis C virus (HCV) infection. However, the effects of ribavirin alone or in combination with IFNa on NK cells are unknown. Methods Extensive ex vivo phenotyping and functional analysis of NK cells from hepatitis C patients was performed during antiviral therapy. Patients were treated for 6 weeks with RBV monotherapy (n = 11), placebo (n = 13) or PEG-IFNa-2a alone (n = 6) followed by PEG-IFNa/RBV combination therapy. The effects of RBV and PEG-IFNa-2a on NK cells were also studied in vitro after co-culture with K562 or Huh7.5 cells. Results Ribavirin monotherapy had no obvious effects on NK cell phenotype or function, neither ex vivo in patients nor in vitro. In contrast, PEG-IFNa-2a therapy was associated with an increase of CD56bright cells and distinct changes in expression profiles leading to an activated NK cell phenotype, increased functionality and decline of terminally differentiated NK cells. Ribavirin combination therapy reduced some of the IFN effects. An activated NK cell phenotype during therapy was inversely correlated with HCV viral load. Conclusions PEG-IFNa activates NK cells possibly contributing to virological responses independently of RBV. The role of NK cells during future IFN-free combination therapies including RBV remains to be determined.

Altered effector functions of NK cells in chronic hepatitis C are associated with IFNL3 polymorphism

Interferon α‐mediated effector functions of NK cells may contribute to the control of HCV replication and the pathogenesis of liver disease. The single‐nucleotide polymorphism rs12979860 near IFNL3 (previously known as IL28B) is important in response to IFN‐α treatment and in spontaneous resolution of acute hepatitis C. The role of the IFNL3 polymorphism in NK cell function is unclear. Thus, we investigated the role of IFNL3 polymorphism in type I IFN‐dependent regulation of NK cell functions in patients with cHC and healthy control subjects. We demonstrated a marked polarization of NK cells toward cytotoxicity in response to IFN‐α stimulation in patients with hepatitis C. That TRAIL up‐regulation was present, particularly in patients with the IFNL3‐TT allele, was supported by a shift in the pSTAT‐1:pSTAT‐4 ratios toward pSTAT‐1. In patients bearing the IFNL3‐TT allele, NK cell effector function correlated with liver disease activity. In contrast, higher cytokine production of NK cells was observed in healthy individuals with the IFNL3‐CC genotype, which may support spontaneous HCV clearance in acute infection. Overall, these findings show that the role of NK cells may differ in chronic infection vs. early antiviral defense and that the IFNL3 genotype differentially influences NK cell function.

Interruption of nucleos(t)ide analogue therapy in HBeAg negative chronic hepatitis B – A new concept to achieve HBsAg decline?

Background: Effective suppression of HBV DNA with nucleoside or nucleotide analogues (NA) has shown to delay disease progression in patients with chronic hepatitis B. However, HBsAg loss during NA treatment is a rare event. Thus, treatment duration with NA is not finite and stopping rules before HBsAg loss are not clearly defined, especially in HBeAg negative patients. Methods: We prospectively stopped NA treatment in patients with HBeAg negative chronic hepatitis B. Inclusion criteria were ongoing antiviral treatment with NA and suppressed HBV DNA 2000 IU/ml. Quantitative HBsAg levels one year before and after treatment cessation were compared to assess differences in HBsAg levels. Results: Data are available for 13 patients with one year follow-up. Virological relapse after treatment cessation was detected in 4 patients (31%) at week 4, in 7 patients (54%) at week 8 and in 1 patient at week 24. No virological relapse occurred in 1 patient. Two patients developed an ALT flare > 5 ULN. No patient experienced signs of liver failure or significant increase of bilirubin. In 11/12 patients with virological relapse treatment was re-initiated with either entecavir or tenofovir and HBV-DNA was successfully suppressed at week 48 follow-up. HBsAg levels showed no significant decline in the year before cessation of NA treatment (1206 ± 1123 IU/ml vs 1232 ± 999 IU/ml, p = 0.86). However, treatment cessation resulted in a significant decline in mean HBsAg levels from baseline to 48 week follow-up (1232 ± 999 IU/ml vs 760 ± 709 IU/ml, p = 0.0012). Interestingly, both patients with ALT flares > 5 ULN showed a decline of HBsAg levels > 2 log from baseline to week 48 follow-up. Conclusion: Treatment cessation in HBeAg negative chronic hepatitis B is safe but leads to virological relapse in > 90% of patients until week 24. However, treatment cessation led to a significant decline in HBsAg levels with the strongest decline observed in patients with ALT flare > 5 ULN. Thus interrupting NA treatment and inducing ALT flares should be further investigated as an option to facilitate HBsAg loss. Corresponding author: Honer zu Siederdissen, Christoph E-Mail:HoenerzuSiederdissen.Christoph@mh-hannover.de