PHOENIX: A randomized controlled trial of peginterferon alfa-2a plus ribavirin as a prophylactic treatment after liver transplantation for hepatitis C virus

Treatment of chronic hepatitis C virus infection after liver transplantation

Chronic hepatitis C virus infection is a leading cause of end stage liver disease and one of the leading indications for liver transplantation. Furthermore, hepatitis C virus recurrence is universal post-transplant leading to decreased graft and patient survival. Recurrent disease related to hepatitis C virus can lead to between 20 and 30% of patients developing recurrent cirrhosis within 5 years. Treatment options with antiviral therapy are limited and are associated with a significant side-effect profile, suboptimal tolerability and inferior response rates. Attention has therefore turned to strategies that can reduce hepatitis C virus recurrence rates post-transplant. Approximately only 30% of patients will achieve a sustained virologic response with current therapy with pegylated interferon and ribavirin. Successful hepatitis C virus eradication is the only factor associated with improved graft and patient survival post liver transplantation. Here we provide an overview of antiviral treatment in patients in the transplant arena and the potential opportunities and challenges with the introduction of new directly acting antivirals in G1 patients.

Management of recurrent hepatitis C in orthotopic liver transplant recipients

End-stage liver disease and hepatocellular carcinoma from chronic hepatitis C are the most common indications for orthotopic liver transplantation and the incidence of both are projected to increase over the next decade. Recurrent hepatitis C virus infection of the allograft is associated with an accelerated progression to cirrhosis, graft loss, and death. This article presents an overview of the natural history of hepatitis C virus recurrence in liver transplant recipients and guidance on optimal management strategies.

Human monoclonal antibody MBL-HCV1 delays HCV viral rebound following liver transplantation: a randomized controlled study

Rapid allograft infection complicates liver transplantation (LT) in patients with hepatitis C virus (HCV). Pegylated interferon-α and ribavirin therapy after LT has significant toxicity and limited efficacy. The effect of a human monoclonal antibody targeting the HCV E2 glycoprotein (MBL-HCV1) on viral clearance was examined in a randomized, double-blind, placebo-controlled pilot study in patients infected with HCV genotype 1a undergoing LT. Subjects received 11 infusions of 50 mg/kg MBL-HCV1 (n=6) or placebo (n=5) intravenously with three infusions on day of transplant, a single infusion on days 1 through 7 and one infusion on day 14 after LT. MBL-HCV1 was well-tolerated and reduced viral load for a period ranging from 7 to 28 days. Median change in viral load (log10 IU/mL) from baseline was significantly greater (p=0.02) for the antibody-treated group (range -3.07 to -3.34) compared to placebo group (range -0.331 to -1.01) on days 3 through 6 posttransplant. MBL-HCV1 treatment significantly delayed median time to viral rebound compared to placebo treatment (18.7 days vs. 2.4 days, p<0.001). As with other HCV monotherapies, antibody-treated subjects had resistance-associated variants at the time of viral rebound. A combination study of MBL-HCV1 with a direct-acting antiviral is underway.

Review article: the treatment of genotype 1 chronic hepatitis C virus infection in liver transplant candidates and recipients

BACKGROUND

Recently, the therapeutic landscape with regard to anti-HCV therapy has changed dramatically. The new directly acting anti-virals (DAAs) have demonstrated improved sustained virological response (SVR) compared with pegylated-interferon and ribavirin.

AIM

To examine and present the latest data with regard to anti-viral therapy in genotype 1 HCV-positive transplant candidates and recipients.

METHODS

An electronic search using Medline was performed. Search terms included 'HCV, DAA and protease inhibitor' in combination with 'treatment pre-transplantation' and 'treatment post-transplantation'.

RESULTS

Patients with advanced fibrosis and cirrhosis have inferior SVR rates compared with patients with minimal fibrosis. A low accelerating dose regimen (LADR) of pegylated interferon and ribavirin (PR) appears to be a safe therapeutic option. Side effects also appear to be more pronounced in patients with advanced disease. Data from the large registration studies with triple therapy (boceprevir or telaprevir plus PR) demonstrated improved SVR rates even in patients with advanced disease, although virological relapse rates were highest amongst these patients. In transplant recipients, initial data are being reported on the use of triple therapy, and although no SVR data are available, promising results are accruing. The drug-drug interactions appear to be manageable. Side effects in particular anaemia appear to be markedly increased in the posttransplant setting.

CONCLUSIONS

The use of the new DAAs in patients with advanced fibrosis/cirrhosis pretransplant and posttransplant appears possible, with manageable side effects and drug-drug interactions, and improved early virological response rates. We recommend that these patients are managed in centres with the appropriate expertise.

Cost-effectiveness analysis of antiviral treatment in liver transplant recipients with HCV infection

Within 5-10 years, 20-40% of hepatitis C virus (HCV)-infected liver transplant recipients can be expected to develop cirrhosis. Here, cost-effectiveness of antiviral therapy was assessed. A Markov model was developed to simulate disease progression and calculate outcome and costs of treatment. In the baseline analysis, Peg-IFN/RBV treatment prevented organ loss/death, gained quality-adjusted life-years (QALYs) and undercut the limit of cost-effectiveness of €50 000/QALY with an incremental cost-effectiveness ratio of approximately €40 400/QALY and €21 000/QALY for HCV genotype 1 and 2/3 patients, respectively. Furthermore, sensitivity analysis testing modified model parameters according to extreme data described in the literature confirmed cost-effectiveness for a lower or higher rate of fibrosis progression, increased non-HCV-related mortality, lower limits of utilities, a time horizon of 30 years, and additional costs in the year of death. On the other hand, cost-effectiveness was lost for patients with genotype 1 in case of doubled antiviral or life-time costs or an increased discount rate of 7%. New treatment strategies for HCV genotype 1 infected patients remained on the same level cost-effective, if additional costs did not exceed €10 774 per 10% sustained virologic response gain. We conclude that Peg-IFN/RBV treatment is cost-effective post transplant. This may support treatment decision in individual cases.

Safety and anti-HCV effect of prolonged intravenous silibinin in HCV genotype 1 subjects in the immediate liver transplant period

BACKGROUND & AIMS

Reinfection of the graft is the rule in patients with HCV cirrhosis undergoing liver transplantation, and HCV-RNA reaches pre-transplantation levels within the first month. Short-term intravenous silibinin monotherapy is safe and shows a potent in vivo anti-HCV effect. We aimed at evaluating the safety and antiviral effect of prolonged intravenous silibinin, started immediately before liver transplantation.

METHODS

Single centre, prospective, pilot study, to assess the safety and effect on HCV-RNA kinetics during at least 21 days of intravenous silibinin monotherapy (20 mg/kg/day) in 9 consecutive HCV genotype 1 subjects, in comparison to a control, non-treated group of 7 consecutive prior transplanted subjects under the same immunosuppressive regimen (basiliximab, steroids, delayed tacrolimus, micophenolate).

RESULTS

Intravenous silibinin led to significant, maintained and progressive HCV-RNA decreases (mean HCV-RNA drop at week 3, -4.1 ± 1.3 log(10)IU/ml), and lack of viral breakthrough during administration. Four patients (44%) reached negative HCV-RNA, maintained during silibinin treatment, vs. none in the control group, but HCV-RNA relapsed in all of them after a median of 21 days (16-28), following silibinin withdrawal. Partial responders to silibinin showed marked decreases in HCV-RNA when compared to controls, but lower than complete responders. There were no clinical adverse effects, and silibinin led to asymptomatic transient hyperbilirubinemia (week 2, 4.2 ± 2.2 vs. 2.5 ± 3.6 mg/dl; p=0.02).

CONCLUSIONS

Prolonged intravenous silibinin monotherapy was safe in the immediate liver transplantation period, leading to a potent and time dependent antiviral effect and lack of HCV-RNA breakthrough during administration. However, HCV-RNA rebounded after withdrawal, and silibinin monotherapy did not avoid reinfection of the graft.

Current management and perspectives for HCV recurrence after liver transplantation

Hepatitis C virus (HCV) infection is one of the leading causes of end-stage liver disease and the main indication for liver transplantation (LT) in most countries. All patients who undergo LT with detectable serum HCV RNA experience graft reinfection. Between 20 and 30% of patients develop cirrhosis within 5 years post-LT. The outcome of transplant patients with cirrhosis on the graft is severe, with a rate of decompensation at 1 year of around 40%. To date, retransplantation is the only option for patients who develop decompensation. Until 2011, standard antiviral therapy, using pegylated interferon (PEG-IFN) and ribavirin (RBV), was the only effective therapy. Obtaining a sustained virological response (SVR) in the setting of LT greatly improves overall and graft survival, but this only concerns 30% of transplanted patients. Direct-acting antivirals (DAA) such as protease inhibitors, polymerase or other non-structural proteins inhibitors represent a new era in HCV-associated liver disease. Although their use in the field of liver transplantation seems to be essential, there are some limitations due to safety and tolerance. One limitation is the potential interaction with calcineurin inhibitors. We describe the preliminary results of triple therapy with boceprevir or telaprevir in terms of efficacy and safety in liver transplant recipients.

Living-donor liver transplantation and hepatitis C

Hepatitis-C-virus- (HCV-) related end-stage cirrhosis is the primary indication for liver transplantation in many countries. Unfortunately, however, HCV is not eliminated by transplantation and graft reinfection is universal, resulting in fibrosis, cirrhosis, and finally graft decompression. In areas with low deceased-donor organ availability like Japan, living-donor liver transplantation (LDLT) is similarly indicated for HCV cirrhosis as deceased-donor liver transplantation (DDLT) in Western countries and accepted as an established treatment for HCV-cirrhosis, and the results are equivalent to those of DDLT. To prevent graft failure due to recurrent hepatitis C, antiviral treatment with pegylated-interferon and ribavirin is currently considered the most promising regimen with a sustained viral response rate of around 30% to 35%, although the survival benefit of this regimen remains to be investigated. In contrast to DDLT, many Japanese LDLT centers have reported modified treatment regimens as best efforts to secure first graft, such as aggressive preemptive antiviral treatment, escalation of dosages, and elongation of treatment duration.

Recurrence of hepatitis C after liver transplantation

Recurrence of hepatitis C virus (HCV) infection following liver transplantation is a major source of morbidity and mortality. The natural history of hepatitis C in the transplant setting is shortened. Overall, one third of HCV-infected recipients have developed allograft cirrhosis due to HCV recurrence by the 5^th-7^th year post-transplantation. The most significant variables which determine disease progression are the use of organs from old donors, the use of an inadequate immunosuppression (too low, inducing treatment rejection episodes, too potent or too rapidly changing), and the presence of comorbid conditions that also impact the quality of the graft (biliary complications, metabolic syndrome). The only factor consistently shown to modify the natural history of recurrent disease is antiviral therapy. A sustained viral response, achieved by one third of those treated with dual therapy, is associated with improved histology, reduced liver-related complications and increased survival. Variables associated with enhanced viral response with dual therapy include an adequate genetic background (IL28B C/C of both donor and recipient), good treatment adherence (full doses of ribavirin, treatment duration), lack of graft cirrhosis at baseline, and viral genotype non-1. Data with triple therapy are encouraging. Response rates of about 60% at end-of-therapy have been described. Drug-drug interactions with calcineurin inhibitors are present but easily manageable with strict trough levels monitoring. Side effects are frequent and severe, particularly anemia, infections and acute renal insufficiency. In the future new oral antivirals will likely prevent viral reinfection. In this review, we will cover the most significant but also controversial aspects regarding recurrent HCV infection, including the natural history, retransplantation, antiviral therapy, and outcome in HIV-HCV patients.

Hepatitis B and C in liver transplantation: new strategies to combat the enemies

Hepatitis B immune globulin-free therapeutic regimens with a nucleos(t)ide analogue (NUC) or NUC combinations after liver transplantation (LT) are currently being investigated for their efficacy and safety as HBV re-infection prophylaxis in clinical studies. Recurrence rates differ among these studies as most of them are limited by a non-randomised study design, small sample size, lack of long-term data and varying time intervals for the switch from combined to purely virostatic prophylaxis. Post-transplant pre-emptive antiviral therapy with pegylated IFN and ribavirin is associated with low sustained virological response rates and was found to have no advantage over treatment of manifest HCV re-infection. Safety and efficacy of triple antiviral therapy including boceprevir or telaprevir in patients with manifest HCV re-infection are currently under investigation in clinical trials. Relevant drug interactions have been shown to occur during calcineurin inhibitor (CNI) and concomitant triple antiviral therapy, which vary with type of CNI and choice of HCV protease inhibitor. Newer direct-acting antivirals with lower or minimal toxicity, when used in combination with immunosuppressives, are worthy of further study in LT patients. This review focuses on hot topics in the management of hepatitis B and C patients before and after LT and offers a critical summarised selection of the corresponding relevant studies published in the current literature or presented at recent liver congresses.

Telaprevir/boceprevir era: From bench to bed and back

Hepatitis C virus (HCV) infects approximately 200 million people worldwide. Interferon-based therapies have dominated over the past two decades. However, the overall response rates remain suboptimal. Thanks to the tremendous effort from both academia and industry, two serine protease inhibitors telaprevir and boceprevir for treating chronic hepatitis C have finally reached the clinic. Although these compounds are only approved for combination use with interferon and ribavirin in genotype 1 HCV infected chronic patients, the management of HCV patients however is now evolving incredibly. Here, we overviewed a series of landmark studies, regarding the clinical development of telaprevir and boceprevir. We discussed the mechanism-of-action of telaprevir/boceprevir and their potential application in HCV-positive liver transplantation patients. We further emphasized some emerging concerns with perspective of further development in this field.

Concentration-guided ribavirin dosing with darbepoetin support and peg-IFN alfa-2a for treatment of hepatitis C recurrence after liver transplantation

Relapse of hepatitis C virus infection after liver transplantation is universal. Standard-of-care (SOC) treatment for relapse offers less satisfactory treatment response than in nontransplanted patients. Tolerance for treatment is suboptimal and withdrawals owing to adverse events induced by treatment frequent. To improve tolerance for SOC, and ribavirin (RBV) in particular, concentration-guided RBV dosing calculated by a formula taking renal function and weight into consideration was utilized. A serum RBV concentration of 10 μm was set as the goal. All patients were given maintenance darbepoetin therapy from 2 weeks prior to initiation of treatment. In total, 21 patients with a mean age of 52 (range 25-64) years were included. The mean RBV concentration at week 4 was 10.2 and 7.36 μm in genotype 1/4 and non-1/4 patients, respectively, and 11.7 and 9.42 at week 12. The mean haemoglobin drop was 25 g/L vs 21 g/L in the genotype 1/4 and non-1/4 group, respectively, a nonsignificant difference. With this treatment approach, 80-90% of patients could be kept adherent to treatment. Sustained viral response was achieved 8/16 (50%) with low-grade fibrosis (fibrosis stage ≤ 2) vs in none of five patients with advanced fibrosis (Fibrosis stage 3 and 4), P < 0.05. We conclude that a treatment algorithm utilizing concentration-guided RBV dosing during darbepoetin maintenance therapy substantially improves tolerance and allows high adherence to a SOC treatment schedule, and that therapy needs to be initiated before advanced fibrosis is developed.

Human monoclonal antibody HCV1 effectively prevents and treats HCV infection in chimpanzees

Hepatitis C virus (HCV) infection is a leading cause of liver transplantation and there is an urgent need to develop therapies to reduce rates of HCV infection of transplanted livers. Approved therapeutics for HCV are poorly tolerated and are of limited efficacy in this patient population. Human monoclonal antibody HCV1 recognizes a highly-conserved linear epitope of the HCV E2 envelope glycoprotein (amino acids 412–423) and neutralizes a broad range of HCV genotypes. In a chimpanzee model, a single dose of 250 mg/kg HCV1 delivered 30 minutes prior to infusion with genotype 1a H77 HCV provided complete protection from HCV infection, whereas a dose of 50 mg/kg HCV1 did not protect. In addition, an acutely-infected chimpanzee given 250 mg/kg HCV1 42 days following exposure to virus had a rapid reduction in viral load to below the limit of detection before rebounding 14 days later. The emergent virus displayed an E2 mutation (N415K/D) conferring resistance to HCV1 neutralization. Finally, three chronically HCV-infected chimpanzees were treated with a single dose of 40 mg/kg HCV1 and viral load was reduced to below the limit of detection for 21 days in one chimpanzee with rebounding virus displaying a resistance mutation (N417S). The other two chimpanzees had 0.5–1.0 log₁₀ reductions in viral load without evidence of viral resistance to HCV1. In vitro testing using HCV pseudovirus (HCVpp) demonstrated that the sera from the poorly-responding chimpanzees inhibited the ability of HCV1 to neutralize HCVpp. Measurement of antibody responses in the chronically-infected chimpanzees implicated endogenous antibody to E2 and interference with HCV1 neutralization although other factors may also be responsible. These data suggest that human monoclonal antibody HCV1 may be an effective therapeutic for the prevention of graft infection in HCV-infected patients undergoing liver transplantation.

The majority of individuals infected with hepatitis C virus (HCV) become chronically infected and many go on to develop liver failure requiring liver transplantation. Unfortunately, the transplanted liver becomes infected with HCV in nearly 100% of transplant patients. Current treatments for HCV are poorly tolerated after liver transplantation and graft health is compromised by infection. We have developed a monoclonal antibody called HCV1 that blocks HCV from infecting liver cells in culture. Using chimpanzees as a model for HCV infection, we demonstrate that HCV1 has the ability to prevent HCV infection. We also show that HCV1 can treat chimpanzees chronically infected with HCV and reduce plasma viral load to below the level of detection for a period of 7 to 21 days. The virus that reemerges in the treated chimpanzees was resistant to HCV1 neutralization demonstrating target engagement. Given the ability of HCV1 to protect chimpanzees from HCV infection, we speculate that HCV1 may be beneficial in HCV- infected patients undergoing liver transplant.

Liver transplantation in the setting of chronic HCV

Recurrent HCV disease is the most common cause of graft loss and patient mortality in HCV-infected liver transplant (LT) recipients. Risk factors for more severe recurrence that are potentially modifiable are older donor age, prolonged cold ischaemia time, prior treated acute rejection, CMV hepatitis, IL28B donor genotype, and post-LT insulin resistance. The most effective means of preventing HCV recurrence is eradicating HCV prior to LT. Select wait-list candidates with compensated or mildly decompensated disease can be considered for antiviral treatment with peginterferon, ribavirin (and protease inhibitor if genotype 1). For the majority of LT patients, HCV treatment must be delayed until post-transplant. Treatment is generally undertaken if histologic severity reaches grade 3 or 4 necroinflammation or stage ≥2 fibrosis, or if cholestatic hepatitis. Achievement of sustained viral response (SVR) post-LT is associated with stabilization of fibrosis and improved graft survival. SVR is attained in ~30% of patients treated with peginterferon and ribavirin. Poor tolerability of therapy is a limitation. Combination therapy with telaprevir or boceprevir added to peginterferon and ribavirin is anticipated to increase efficacy but with higher rates of adverse effects and challenges in managing drug-drug interactions between the protease inhibitors and calcineurin inhibitors/sirolimus.

Antiviral therapy and fibrosis progression in patients with mild-moderate hepatitis C recurrence after liver transplantation. A randomized controlled study

BACKGROUNDS/AIMS

We evaluated the effect of antiviral therapy on fibrosis progression in patients with histological features of mild/moderate HCV disease recurrence defined by a Grading score≥4 and Staging score up to 3 (Ishak) at 1 year after liver transplantation.

METHODS

Seventy-three consecutive patients with mild/moderate recurrence were randomized either to no treatment or to receive Pegilated-Interferon-alfa-2b and ribavirin for 52 weeks. Liver biopsies obtained at baseline (1 year after transplantation) and 2 years afterwards were evaluated for assessment of disease progression, defined as worsening of at least 2 staging points or progression to stage 4 or higher.

RESULTS

As for these two major histological end points there were no statistically significant differences between the 2 groups (36.1% vs. 50%, p=0.34 and 36.1% vs. 38.9%, p=1). Fifteen treated patients (41%) achieved a sustained virological response which was associated with a reduced risk of fibrosis worsening for both endpoints when compared to viremic patients (p=0.04).

CONCLUSIONS

Although antiviral-therapy was beneficial in preventing fibrosis progression in patients achieving a sustained virological response, the majority of the overall population of our patients with mild-moderate disease recurrence could not benefit from antiviral therapy either because they either could not be treated or did not respond to treatment (EudraCT number: 2005-005760).

Update in liver transplantation

PURPOSE OF REVIEW

Successful transplant outcomes require optimal patient selection and timing. This review will update clinicians with current status and challenges in liver transplantation. Currently, the major limitation facing liver transplant centers is the shortage of organs. The limited availability of organs has led to long waiting periods for liver transplantation and consequently many patients become seriously ill or die while on the waiting list.

RECENT FINDINGS

This has major implications in the selection of patients, as well as the timing of transplant, for optimal use of these scarce organs. Indications and contraindications have changed slightly over the years and will be reviewed in this article.

SUMMARY

Timing for transplantation has changed more dramatically in the recent years because major changes to organ allocation systems have been undertaken to provide clinicians with a better way to prioritize patients for liver transplant.

Hepatitis C virus treatment pre- and post-liver transplantation

Liver disease caused by the hepatitis C virus is the main indication for liver transplantation in Western countries. However, HCV re-infection post-transplantation is constant and recent data confirm that it significantly impairs patient and graft survival. Chronic HCV infection develops in 75-90% of patients, and 5-30% ultimately progress to cirrhosis within 5 years. Because of the impact of HCV recurrence on graft and patient survival, several treatment strategies have been evaluated. Antiviral therapy could be administered before transplantation to suppress viral replication and reduce the risk of recurrence. However, this approach is applicable in around 50% of patients and tolerance is poor, particularly in patients with decompensated cirrhosis. Pre-emptive therapy in the early post-transplant period is limited by the high rate of side effects. Frequently, antiviral therapy is initiated when HCV recurs to obtain viral eradication and/or reduce disease progression. Treatment of established graft lesions with Pegylated Interferon (PEG-IFN) and Ribavirin (RBV) combination therapy results in a sustained virological response (SVR) in around 30% of patients. The new classes of potent and direct antiviral agents (DAA) will certainly improve the results of pre- and post-transplant antiviral therapy. However, at the present time, no data are available on the use of these drugs in patients with decompensated cirrhosis or post-transplant hepatitis.

A human monoclonal antibody targeting scavenger receptor class B type I precludes hepatitis C virus infection and viral spread in vitro and in vivo

Endstage liver disease caused by chronic hepatitis C virus (HCV) infection is the leading indication for liver transplantation in the Western world. However, immediate reinfection of the grafted donor liver by circulating virus is inevitable and liver disease progresses much faster than the original disease. Standard antiviral therapy is not well tolerated and usually ineffective in liver transplant patients, whereas anti-HCV immunotherapy is hampered by the extreme genetic diversity of the virus and its ability to spread by way of cell-cell contacts. We generated a human monoclonal antibody against scavenger receptor class B type I (SR-BI), monoclonal antibody (mAb)16-71, which can efficiently prevent infection of Huh-7.5 hepatoma cells and primary hepatocytes by cell-culture-derived HCV (HCVcc). Using an Huh7.5 coculture system we demonstrated that mAb16-71 interferes with direct cell-to-cell transmission of HCV. Finally we evaluated the in vivo efficacy of mAb16-71 in "human liver urokinase-type plasminogen activator, severe combined immune deficiency (uPA-SCID) mice" (chimeric mice). A 2-week anti-SR-BI therapy that was initiated 1 day before viral inoculation completely protected all chimeric mice from infection with serum-derived HCV of different genotypes. Moreover, a 9-day postexposure therapy that was initiated 3 days after viral inoculation (when viremia was already observed in the animals) suppressed the rapid viral spread observed in untreated control animals. After cessation of anti-SR-BI-specific antibody therapy, a rise of the viral load was observed.

CONCLUSION

Using in vitro cell culture and human liver-chimeric mouse models, we show that a human mAb targeting the HCV coreceptor SR-BI completely prevents infection and intrahepatic spread of multiple HCV genotypes. This strategy may be an efficacious way to prevent infection of allografts following liver transplantation in chronic HCV patients, and may even hold promise for the prevention of virus rebound during or following antiviral therapy.

Future treatment of patients with HCV cirrhosis

Of all hepatitis C virus (HCV) patients, those with cirrhosis are most in need of treatment because of increased morbidity and mortality. Treatment with pegylated-interferon (PEG-IFN) and ribavirin (RBV) (PR) has definitely shown the benefits of successful treatment by improving fibrosis, causing the regression of cirrhosis and reducing and preventing cirrhosis-related complications. However, the sustained virological response (SVR) is lower in patients with cirrhosis. First generation protease inhibitors (boceprevir and telaprevir) in combination with PR are a major advancement in the treatment of both naïve and treatment-experienced genotype 1 patients. In naïve patients, the SVR rate with the triple regimen with boceprevir was increased by 14% in patients with severe fibrosis or cirrhosis compared with PR. This benefit was lower than that observed in patients with mild or moderate fibrosis (30%). The SVR rate of the triple regimen with telaprevir was increased by 10-30% compared with PR in patients with severe fibrosis or cirrhosis compared with nearly 30% in patients with mild or moderate fibrosis. In treatment-experienced patients, previous relapsers have the highest increase in SVR with the triple regimen compared with PR, whatever the status of fibrosis. Previous partial or non-responder patients with cirrhosis had lower SVR rates than those without cirrhosis. However, the benefits of telaprevir and boceprevir vs PR was maintained. Previous non-responder patients with cirrhosis benefited the least from treatment. The relapse rate was always higher and side effects were more frequent in patients with cirrhosis compared with those without. First generation protease inhibitors plus PR appear to be a new step forward in the management of HCV genotype 1 patients with cirrhosis.

Liver transplantation and hepatitis C

Hepatitis-C-virus- (HCV-) related end-stage cirrhosis is the primary indication for liver transplantation in many countries. Unfortunately, however, HCV is not eliminated by transplantation and graft reinfection is universal, resulting in fibrosis, cirrhosis, and finally graft decompensation. The use of poor quality organs, particularly from older donors, has a highly negative impact on the severity of recurrence and patient/graft survival. Although immunosuppressive regimens have a considerable impact on the outcome, the optimal regimen after liver transplantation for HCV-infected patients remains unclear. Disease progression monitoring with protocol biopsy and new noninvasive methods is essential for predicting patient/graft outcome and starting antiviral treatment with the appropriate timing. Antiviral treatment with pegylated interferon and ribavirin is currently considered the most promising regimen with a sustained viral response rate of around 30% to 35%, although the survival benefit of this regimen remains to be investigated. Living-donor liver transplantation is now widely accepted as an established treatment for HCV cirrhosis and the results are equivalent to those of deceased donor liver transplantation.

Antiviral treatment for HCV recurrence after liver transplantation: when, how much and for how long?

Chronic HCV infection is one of the leading causes of end-stage liver disease and hepatocellular carcinoma worldwide, and it constitutes one of the principal indications for liver transplant. However, recurrent HCV infection after liver transplant is nearly universal, and leads to decreased patient and graft survival in the long-term. Strategies to approach this problem that is commonly encountered in clinical practice include treating patients in order to obtain viral clearance before the transplant, pre-emptive treatment, which refers to therapy initiation before there is histological evidence of disease, and treatment for established recurrence. Therapy at these diverse time points poses varied challenges regarding the feasibility of the treatment, possibility of treatment completion, risk of adverse effects and different response rates. Furthermore, advances are being made in identifying prognostic markers of viral response, which could aid in decreasing the disease burden.

Griffithsin has antiviral activity against hepatitis C virus

Hepatitis C virus (HCV)-infected patients undergoing liver transplantation universally experience rapid reinfection of their new liver graft. Current treatment protocols do not prevent graft reinfection and, in addition, an accelerated disease progression is observed. In the present study, we have evaluated a novel strategy to prevent HCV infection using a lectin, griffithsin (GRFT) that specifically binds N-linked high-mannose oligosaccharides that are present on the viral envelope. The antiviral effect of GRFT was evaluated in vitro using the HCV pseudoparticle (HCVpp) and HCV cell culture (HCVcc) systems. We show here that preincubation of HCVpp and HCVcc with GRFT prevents infection of Huh-7 hepatoma cells. Furthermore, GRFT interferes with direct cell-to-cell transmission of HCV. GRFT acts at an early phase of the viral life cycle by interfering in a genotype-independent fashion with the interaction between the viral envelope proteins and the viral receptor CD81. The capacity of GRFT to prevent infection in vivo was evaluated using uPA(+/+)-SCID mice (uPA stands for urokinase-type plasminogen activator) that harbor human primary hepatocytes in their liver (chimeric mice). In this proof-of-concept trial, we demonstrated that GRFT can mitigate HCV infection of chimeric mice. Treated animals that did become infected demonstrated a considerable delay in the kinetics of the viral infection. Our data demonstrate that GRFT can prevent HCV infection in vitro and mitigate HCV infection in vivo. GRFT treatment of chronically infected HCV patients undergoing liver transplantation may be a suitable strategy to prevent infection of the liver allograft.