Efficacy and tolerance of interferon-alpha(2b) in the treatment of chronic hepatitis C virus infection in haemodialysis patients. Pre- and post-renal transplantation assessment

Interventions for dialysis patients with hepatitis C virus (HCV) infection

BACKGROUND

Hepatitis C virus (HCV) infection is common in chronic kidney disease (CKD) patients on dialysis, causes chronic liver disease, may increase the risk of death, and impacts kidney transplant outcomes. Direct-acting antivirals have replaced interferons because of better efficacy and tolerability. This is an update of a review first published in 2015.

OBJECTIVES

We aimed to look at the benefits and harms of interventions for HCV in CKD patients on dialysis: death, disease relapse, treatment response/discontinuation, time to recovery, quality of life (QoL), cost-effectiveness, and adverse events. We aimed to study comparisons of available interventions, compared with placebo, control, with each other and with newer treatments.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant's Specialised Register to 23 February 2023 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE and EMBASE, handsearching conference proceedings, and searching the International Clinical Trials Register Portal (ICTRP) and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs), quasi-RCTs, first period of randomised cross-over studies on interventions for HCV in CKD on dialysis were considered.

DATA COLLECTION AND ANALYSIS

Summary estimates of effect were obtained using a random-effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI). Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

Three studies were included in this update, therefore 13 studies (997 randomised participants) met our inclusion criteria. Overall, the risk of bias was judged low in seven studies, unclear in four, low to unclear in one, and high in one study. Interventions included standard interferon, pegylated (PEG) interferon, standard or PEG interferon plus ribavirin; direct-acting antivirals, and direct-acting antivirals plus PEG interferon plus ribavirin. Compared to placebo or control, standard interferon may make little or no difference to death (5 studies, 134 participants: RR 0.89, 95% CI 0.06 to 13.23) or relapse (low certainty evidence), probably improves end-of-treatment response (ETR) (5 studies, 132 participants: RR 8.62, 95% CI 3.03 to 24.55; I² = 0%) (moderate certainty evidence), and probably makes little or no difference to sustained virological response (SVR) (4 studies, 98 participants: RR 3.25, 95% CI 0.81 to 13.07; I² = 53%), treatment discontinuation (4 studies, 116 participants: RR 4.59, 95% CI 0.49 to 42.69; I² = 63%), and adverse events (5 studies, 143 participants: RR 3.56, 95% CI 0.98 to 13.01; I² = 25%) (moderate certainty evidence). In low certainty evidence, PEG interferon (1 study, 50 participants) may improve ETR (RR 1.53, 95% CI 1.09 to 2.15) but may make little or no difference to death (RR 0.33, 95% CI 0.01 to 7.81), SVR (RR 2.40, 95% CI 0.99 to 5.81), treatment discontinuation (RR 0.11, 95% CI 0.01 to 1.96), adverse events (RR 0.11, 95% CI 0.01 to 1.96) and relapses (21/38 relapsed) (RR 0.72, 95% CI 0.41 to 1.25) compared to standard interferon. In moderate certainty evidence, high-dose PEG interferon (alpha-2a and alpha-2b) may make little or no difference to death (2 studies, 97 participants: RR 4.30, 95% CI 0.76 to 24.33; I² = 0%), ETR (RR 1.42, 95% CI 0.51 to 3.90; I² = 20%), SVR (RR 1.19, 95% CI 0.68 to 2.07; I² = 0%), treatment discontinuation (RR 1.20, 95% CI 0.63 to 2.28; I² = 0%) or adverse events (RR 1.05, 95% CI 0.61 to 1.83; I² = 27%) compared to low-dose PEG interferon. High-dose PEG interferon may make little or no difference to relapses (1 study, 43 participants: RR 1.11, 95% CI 0.45 to 2.77; low certainty evidence). There were no significant subgroup differences. Standard interferon plus ribavirin may lead to higher treatment discontinuation (1 study, 52 participants: RR 2.97, 95% CI 1.19 to 7.36; low certainty evidence) compared to standard interferon alone.  In low certainty evidence, PEG interferon plus ribavirin (1 study, 377 participants) may improve SVR (RR 1.80, 95% CI 1.46 to 2.21), reduce relapses (RR 0.33, 95% CI 0.23 to 0.48), slightly increase the number with adverse events (RR 1.10, 95% CI 1.01 to 1.19), and may make little or no difference to ETR (RR 1.01, 95% CI 0.94 to 1.09) compared to PEG interferon alone. The evidence is very uncertain about the effect of PEG interferon plus ribavirin on treatment discontinuation (RR 1.71, 95% CI 0.69 to 4.24) compared to PEG interferon alone. One study reported grazoprevir plus elbasvir improved ETR (173 participants: RR 174.99, 95% CI 11.03 to 2775.78; low certainty evidence) compared to placebo. It is uncertain whether telaprevir plus ribavirin (high versus low initial dose) plus PEG interferon for 24 versus 48 weeks (1 study, 35 participants) improves ETR (RR 1.02, 95% CI 0.67 to 1.56) or SVR (RR 1.02, 95% CI 0.67 to 1.56) because the certainty of the evidence is very low.  Data on QoL, cost-effectiveness, cardiovascular outcomes and peritoneal dialysis were not available.

AUTHORS' CONCLUSIONS

In dialysis patients with HCV infection grazoprevir plus elbasvir probably improves ETR. There is no difference in ETR or SVR for combinations of telaprevir, ribavirin and PEG interferon given for different durations and doses. Though no longer in use, PEG interferon was more effective than standard interferon for ETR but not SVR. Increasing doses of PEG interferon did not improve responses. The addition of ribavirin to PEG interferon may result in fewer relapses, higher SVR, and higher numbers with adverse events.

The Management of Viral Hepatitis in CKD Patients: An Unresolved Problem

Chronic kidney disease (CKD) patients in dialysis (HD) show peculiar, atypical features of clinical presentation and diseases (cardiovascular, metabolic, hematologic). This is also true for viral hepatitis infections, for which CKD patients represent an important risk group. In the past, hepatitis B virus (HBV) was the major cause of viral hepatitis in end-stage renal disease (ESRD). However, the introduction of a rigorous infection-control strategy, routine screening of patients and staff for hepatitis B serologic markers, vaccination of susceptible patients and staff, use of separate rooms and dedicated machines for HD of HbsAg-positive patients have all led to a decline in the spread of HBV infection in dialysis. Despite the prevalence of the antibody-hepatitis C virus (HCV), there has been a marked decrease in HD patients; after the introduction of routine screening for HCV and the use of erythropoietin, its occurrence ranges from 5% to 25% in the United States, with a prevalence of 6.8% in Europe. In CKD and in HD patients, the presence of HBV and HCV is an independent and significant risk factor for death and this risk may be at least partially attributed to chronic liver disease with its attendant complications. Liver disease can progress with modest hepatic inflammation and prominent fibrosis; the natural history of viral hepatitis in these patients is dependent on the immune dysfunction typical of kidney disease. Despite recent advances in antiviral therapy, there are still many uncertainties in regards to the efficacy and long-term outcomes of treatment with antiviral agents.

Spectrum of hepatitis B and renal involvement

Renal involvement in hepatitis B occurs in various spectrums and its knowledge is important for clinicians in management of patients. The renal diseases most commonly associated with hepatitis B virus (HBV) infection include membranous nephropathy, membranoproliferative glomerulonephritis and Polyarteritis nodosa. The widespread use of hepatitis B vaccination has decreased the incidence of HBV-related renal diseases. The incidence of HBV infection in dialysis patients has significantly decreased over the past few decades because of screening of blood products for hepatitis B surface antigen (HBsAg) and hepatitis B core antibody, implementation of infection control measures and hepatitis B vaccination. The definition of acute kidney injury has been recently modified in cirrhotic population, helping in prognosis and prediction of mortality. The most common etiologies of acute kidney injury in this cirrhotic population, which account for 80% to 90% of all cases, include volume depletion, acute tubular necrosis and hepatorenal syndrome. Treatment with oral nucleoside/tide analogues (NA) brought a new paradigm in the management of HBsAg positive glomerulonephritis, kidney transplant recipients and dialysis patients, resulting in effective viral suppression, reduced hepatic complications and improved patient survival, without compromising renal allograft outcome. NAs are cleared by the kidneys and therefore their dosage has to be adjusted in all patients with impaired renal function. This article reviews the recent knowledge of the pathogenesis and treatment of HBV-related glomerulonephritis and discusses the management of hepatitis B in patients on dialysis, kidney transplant recipients and cirrhotics, which is continuously evolving.

When and how can nephrologists treat hepatitis C virus infection in dialysis patients?

Hepatitis C virus (HCV) infection, a major cause of end-stage liver disease, is a common comorbidity in patients on dialysis and causes increased morbidity and mortality. Historically HCV has been extremely difficult to cure with interferon and ribavirin-based therapies, which are also associated with significant side effects, and few dialysis patients ever received HCV treatment. However, in the last 4 years, interferon-free direct-acting antiviral therapies have been approved, and several combinations have been studied in dialysis patients. A recently approved, pan-genotypic, direct-acting antiviral regimen, glecaprevir and pibrentasvir, may simplify prescribing. The simplicity of these new therapies, with few side effects, makes it possible for nephrologists to treat HCV infection in their patients on dialysis. We review the workflow and motivation behind nephrology-led management of HCV infection. We highlight the importance of identifying which patients need referral to a hepatologist or HCV specialist prior to treatment and which can be managed by their nephrologist. Nephrologist involvement would lead to improved access to treatment and ensure that appropriate patients are referred for HCV treatment. In this paper, we review the background of HCV infection, its effect on dialysis patients, and impact on kidney transplantation. In addition, we outline the therapy options for each genotype of HCV, and we discuss the benefits and barriers to nephrology-led HCV treatment.

Interventions for dialysis patients with hepatitis C virus (HCV) infection

BACKGROUND

Hepatitis C virus (HCV) infection is common in chronic kidney disease (CKD) patients on dialysis, causes chronic liver disease, increases mortality and impacts kidney transplant outcomes. Sustained response to the preferred treatment with standard or pegylated (PEG) interferon is seen in 39% with side effects necessitating treatment discontinuation in 20%. We collated evidence for treatment response and harms of interventions for HCV infection in dialysis.

OBJECTIVES

We aimed to look at the benefits and harms of various interventions for HCV infection in CKD patients on HD or peritoneal dialysis, specifically on mortality, disease relapse, response to treatment, treatment discontinuation, time to recovery, quality of life, cost effectiveness,adverse effects, and other outcomes. We aimed to study comparisons of available interventions with a placebo or control group, combinations of interventions with placebo or control group, interventions with each other singly and in combination, available standard interventions with newer treatment modalities.

SEARCH METHODS

We searched Cochrane Kidney and Transplant's Specialised Register to 24 March 2015 through contact with the Trials' Search Co-ordinator. We also checked references of reviews, studies and contacted study authors to identify additional studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs), quasi-RCTs, first period of randomised cross-over studies on interventions for HCV in CKD on dialysis were considered.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by the Cochrane Collaboration and also collected adverse effects data listed in included RCTs.

MAIN RESULTS

Ten RCTs (361 participants) met our inclusion criteria. Five RCTs (152 participants, 134 analysed) with low to moderate quality of evidence compared standard recombinant interferon with placebo or control. There was no significant difference for mortality (5 studies (134 participants): RR 0.89, 95% CI 0.06 to 13.23), relapses (1 study (36 participants): RR 0.72, 95% CI 0.28 to 1.88), sustained virological response (4 studies (98 participants): RR 3.25, 95% CI 0.81 to 13.07), treatment discontinuation (4 studies (116 participants): RR 4.59, 95% CI 0.49 to 42.69) and number with adverse events (5 studies (143 participants): RR 3.56, 95% CI 0.98 to 13.01). End of treatment response was significantly more for standard interferon (5 studies (132 participants): RR 8.62, 95% CI 3.03 to 24.55). There was overall low to unclear risk of bias and no significant heterogeneity.One RCT (50 participants) with moderate quality of evidence compared PEG interferon and standard interferon. There was no significant difference in mortality (RR 0.33, 95% CI 0.01 to 7.81), relapses (RR 0.72, 95% CI 0.41 to 1.25), sustained virological response (RR 2.40, 95% CI 0.99 to 5.81), treatment discontinuation (RR 0.11, 95% CI 0.01 to 1.96) and number with major adverse events (RR 0.11, 95% CI 0.01 to 1.96). End of treatment response was significantly more for PEG interferon (RR 1.53, 95% CI 1.09 to 2.15). There was overall low risk of bias.Two RCTs (97 participants) with moderate quality of evidence compared two doses of two different preparations of PEG interferon. Subgroup analysis comparing high and low doses of PEG interferon alpha-2a (135 µg/week versus 90 µg/week) and PEG interferon alpha-2b (1 µg/kg versus 0.5 µg/kg body weight/week) found no significant difference in mortality (2 studies (97 participants): RR 4.30, 95% CI 0.76 to 24.33), relapses (1 study (81 participants): RR 1.11, 95% CI 0.45 to 2.77), end of treatment response (2 studies (97 participants): RR 1.42, 95% CI 0.51 to 3.90), sustained virological response (2 studies (97 participants): RR 1.19, 95% CI 0.68 to 2.07), treatment discontinuation (2 studies (97 participants): RR 1.20, 95% CI 0.63 to 2.28), patients with adverse events (2 studies (97 participants): RR 1.05, 95% CI 0.61 to 1.83) or serious adverse events (2 studies (97 participants): RR 1.24, 95% CI 0.72 to 2.14). Both had overall low risk of bias and no significant subgroup differences.Two RCTs (62 participants) with moderate quality of evidence compared standard or PEG interferon alone or in combination with ribavirin. The only reported outcome in both was treatment discontinuation which was significantly more with ribavirin in the one study (RR 0.34, 95% CI 0.14 to 0.84) and pooled 7/10 in the second.No RCTs had data on time to recovery, cost-effectiveness, quality of life, and other outcomes and in peritoneal dialysis.

AUTHORS' CONCLUSIONS

Our review demonstrated that in CKD patients on haemodialysis with HCV infection treatment with standard interferon brings about an end of treatment but not a sustained virological response and is relatively well tolerated. PEG interferon is more effective than standard interferon for end of treatment response but not for sustained response; both were equally tolerated. Increasing doses of PEG interferon did not improve responses but high and low doses are equally tolerated. Addition of ribavirin results in more treatment discontinuation.

Hepatitis C virus infection and dialysis: 2012 update

Hepatitis C virus infection is still common among dialysis patients, but the natural history of HCV in this group is not completely understood. Recent evidence has been accumulated showing that anti-HCV positive serologic status is significantly associated with lower survival in dialysis population; an increased risk of liver and cardiovascular disease-related mortality compared with anti-HCV negative subjects has been found. According to a novel meta-analysis (fourteen studies including 145,608 unique patients), the adjusted RR for liver disease-related death and cardiovascular mortality was 3.82 (95% CI, 1.92; 7.61) and 1.26 (95% CI, 1.10; 1.45), respectively. It has been suggested that the decision to treat HCV in patients with chronic kidney disease be based on the potential benefits and risks of therapy, including life expectancy, candidacy for kidney transplant, and co-morbidities. According to recent guidelines, the antiviral treatment of choice in HCV-infected patients on dialysis is mono-therapy but fresh data suggest the use of modern antiviral approaches (i.e., pegylated interferon plus ribavirin). The summary estimate for sustained viral response and drop-out rate was 56% (95% CI, 28-84) and 25% (95% CI, 10-40) in a pooled analysis including 151 dialysis patients on combination antiviral therapy (conventional or pegylated interferon plus ribavirin).

KASL Clinical Practice Guidelines: Management of chronic hepatitis B

The guideline on the management of chronic hepatitis B (CHB) was first developed in 2004 and revised in 2007 by the Korean Association for the Study of the Liver (KASL). Since then there have been many developments, including the introduction of new antiviral agents and the publications of many novel research results from both Korea and other countries. In particular, a large amount of knowledge on antiviral resistance--which is a serious issue in Korea--has accumulated, which has led to new strategies being suggested. This prompted the new guideline discussed herein to be developed based on recent evidence and expert opinion.

TARGET POPULATION

The main targets of this guideline comprise patients who are newly diagnosed with CHB and those who are followed or treated for known CHB. This guideline is also intended to provide guidance for the management of patients under the following special circumstances: malignancy, transplantation, dialysis, coinfection with other viruses, pregnancy, and children.

Treatment of hepatitis C virus infection in patients on maintenance hemodialysis: a single United Arab Emirates center experience

BACKGROUND

Hepatitis C is prevalent among hemodialysis patients. In patients with normal kidney function, treatment with pegylated interferon and ribavirin can lead to eradication of HCV (hepatitis C virus). But the treatment is more problematic in patients with impaired kidney function, in part due to the altered pharmacokinetics of these medications. Despite recent guidelines, the optimal strategy in this group of patients is not well defined.

METHOD

In a retrospective study, we reviewed all patients with chronic hepatitis C on hemodialysis treated at Sheikh Khalifa Medical City, in the United Arab Emirates between 2003 and 2009. The aim of our study was to determine the rate of sustained viral response (SVR) and to establish the safety and rate of dropouts in the different treatment regimens used (patients treated with peginterferon only and patients treated with peginterferon and low dose ribavirin).

RESULTS

22 patients were treated during this period. 5 patients received monotherapy with a reduced dose of peginterferon alfa 2b s.c. once weekly while 17 patients were treated with a combination of reduced dose of peginterferon alfa 2a or 2b s.c. once weekly and a low dose ribavirin (200mg/day). A SVR was achieved in 73% (16/22 patients) of the total patient population and in 76% (13/17 patients) in the sub-group of patients treated with a combination therapy. The tolerability was high. No patients had to discontinue their treatment. The use of ESA (erythropoietin stimulating agents) and G-CSF was common in the combination therapy (94% and 53% respectively).

CONCLUSION

In our study of patients on hemodialysis with chronic hepatitis C, the use of peginterferon or a combination of peginterferon with a low daily dose of ribavirin achieved a high rate of SVR and the rate of dropout was low after pursuing an aggressive management of side effects.

Long-term viral negativity after interferon for chronic hepatitis C virus infection in hemodialysis

BACKGROUND AND OBJECTIVES

Interferon (IFN) and pegylated-IFN treatment of hepatitis C virus (HCV) infection in hemodialysis patients result in sustained virological response (SVR) rates of 45% and 37%, respectively. Although most nonhemodialysis patients who achieve SVR remain persistently viral negative, the durability of SVR in hemodialysis patients is unknown. We analyzed the rate of long-term virological negativity in hemodialysis patients who achieved SVR after IFN or pegylated-IFN through analysis of patient-level data.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

After performing a systematic literature review for IFN-based treatment of hemodialysis patients with chronic HCV infection, we extracted patient-level data on patients who achieved SVR. We performed life table analysis to estimate long-term virological negativity rates after SVR in patients who continued on hemodialysis or subsequently underwent kidney transplantation.

RESULTS

Long-term HCV RNA outcomes following SVR were available for 121 hemodialysis patients (20 studies) and 45 patients who subsequently underwent transplantation (11 studies). The probability of remaining HCV RNA negative was 86% (95% confidence interval, 77% to 96%) for patients followed on hemodialysis 48 months after SVR and 95% (95% confidence interval, 89% to 100%) for kidney recipients followed 48 months after transplant.

CONCLUSIONS

Viral negativity from IFN-based HCV treatment in hemodialysis patient appears durable during extended follow-up, including after kidney transplantation. The certainty of the viral negativity estimate is limited by the small number with follow-up beyond 48 months or longer. Transplantation does not confer an increased risk of relapse. Future research should investigate whether IFN-based treatment improves clinical outcomes for hemodialysis patients.

Treatment of hepatitis C virus infection in patients with end-stage renal disease

Hepatitis C virus (HCV) infection is a major health problem in patients with end-stage renal disease (ESRD). The incidence of acute HCV infection during maintenance dialysis is much higher than that in the general population because of the risk of nosocomial transmission. Following acute HCV infection, most patients develop chronic HCV infection, and a significant proportion develop chronic hepatitis, cirrhosis, and even hepatocellular carcinoma. Overall, chronic hepatitis C patients on hemodialysis bear an increased risk of liver-related morbidity and mortality, either during dialysis or after renal transplantation. Interferon (IFN) therapy is modestly effective for the treatment of HCV infection in ESRD patients. Conventional or pegylated IFN monotherapy has been used to treat acute hepatitis C in ESRD patients with excellent safety and efficacy. Regarding chronic hepatitis C, approximately one-third of patients can achieve a sustained virological response (SVR) after conventional or pegylated IFN monotherapy. The combination of low-dose ribavirin and conventional or pegylated IFN has further improved the SVR rate in treatment-naïve or retreated ESRD patients in clinical trials. Similar to the treatment of patients with normal renal function, baseline and on-treatment HCV virokinetics are useful to guide optimized therapy in ESRD patients. Of particular note, IFN-based therapy is not recommended at the post-renal transplantation stage because of the low SVR rate and risk of acute graft rejection. In conclusion, ESRD patients with HCV infection should be encouraged to receive antiviral therapy, and those who achieve an SVR usually have long-term, durable, virological, biochemical, and histological responses.

Chronic viral hepatitis in kidney transplantation

Chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infection in potential kidney transplant candidates-once considered absolute contraindications to kidney transplantation-no longer creates overt barriers to transplantation. Advances in the medical management of HBV and HCV infection have created opportunities for a substantial number of patients to be effectively treated with antiviral therapy before transplantation. For HBV infection, a number of new drugs enable clearance of the virus with minimal adverse effects and drug resistance. Pretransplantation antiviral therapy is advisable for patients with HCV infection, but adverse effects are common and viral eradication remains challenging. Regardless of viral clearance, pretransplant patients without bridging fibrosis (as confirmed by liver biopsy) or clinical stigmata of cirrhosis should be considered for kidney transplantation as survival is superior when compared to treatment with dialysis, and progression of liver disease is unlikely. For patients with advanced liver disease, simultaneous liver-kidney transplantation is an important consideration. These treatment advances further increase the burden of organ donor shortage; however, organs from deceased donors with chronic HBV or HCV infection could be efficiently allocated to certain individuals with a viral infection of the same type to increase the pool of available transplant organs.

Hepatitis C and kidney disease

Multiple extrahepatic manifestations have been associated with chronic hepatitis C, the most important among them being cryoglobulinemia, glomerulonephritis, porphyria cutanea tarda, lichen planus, seronegative arthritis, and lymphoproliferative disorders as in the sudies of Bonkovsky and Mehta (2001) and El-Serag et al. (2002). We will discuss in this paper chronic hepatitis C- related kidney disease and course and management of patients with chronic hepatitis C in special circumstances like hemodialysis and kidney transplantation.

Hepatic disorders in chronic kidney disease

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infection are the most common and serious causes of liver damage in patients with chronic kidney disease (CKD). The natural histories of HBV and HCV infections in patients with CKD are not fully understood; however, recent evidence has emphasized the adverse effect of HBV and/or HCV infection on survival in this population. Chronic liver disease is the fourth most important cause of death after renal transplantation. The negative effect of HCV infection on survival among renal transplant recipients has been linked to liver dysfunction and extrahepatic complications, such as chronic glomerulonephritis, post-transplantation diabetes mellitus, chronic allograft nephropathy, and sepsis. The transmission of HCV by solid organ transplantation has been unequivocally demonstrated. Renal transplant recipients who receive kidneys from HCV-positive donors are at increased risk of death. Although several studies have shown that in patients with HCV infection and chronic renal failure renal transplantation is associated with better survival than is dialysis, recent clinical guidelines recommend that kidneys from HCV-infected donors should not be used in HCV-seropositive recipients without detectable HCV viremia. Monotherapy with conventional interferon has been suggested to be a useful treatment for hepatitis C infection in patients on dialysis. Although no evidence suggests that patients with CKD are more prone to suffer from hepatic toxic effects than individuals with normal kidney function, patients with CKD usually receive multiple medications; and drug interactions may, therefore, have a role in the pathogenesis of drug-induced liver disease in this population.

Interferon for hepatitis C virus in hemodialysis--an individual patient meta-analysis of factors associated with sustained virological response

BACKGROUND AND OBJECTIVES

Hepatitis C virus (HCV) infection is prevalent in hemodialysis patients and causes excess mortality. Interferon (IFN) treatment of chronic HCV infection in hemodialysis patients results in high sustained virological response (SVR) rates 6 mo after treatment. The authors aimed to identify factors associated with SVR in hemodialysis patients through analysis of individual patient data obtained from systematic review of published literature.

DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS

Medline was searched from 1966 through February 2009, and prospective studies describing IFN treatment of hemodialysis patients with chronic HCV infection with published individual patient data were included. To identify factors associated with SVR, logistic regression was applied with adjustment for study.

RESULTS

Twenty studies of IFN treatment provided data on 428 patients. Overall SVR was 45% and in univariate analyses was higher with: 1) three million units or higher three times weekly of IFN; 2) treatment for at least 6 mo; 3) treatment completion; 4) lower baseline HCV RNA; 5) female gender; and 6) early virological negativity. Although limited by missing data, these relationships persisted in multivariate regression.

CONCLUSIONS

SVR is more likely with larger IFN dose, longer treatment duration, treatment completion, female gender, lower HCV RNA and early virological negativity. For appropriate treatment candidates, regimens should consist of three million units of IFN three times weekly for at least 6 mo, with patients encouraged to complete the full course.

A Six‐Year Follow‐Up After Interferon‐Alpha Monotherapy for Chronic Hepatitis C Infection in Hemodialysis Patients

Interferon-alpha (IFN) has been accepted as an effective treatment for chronic hepatitis C virus (HCV) infection in hemodialysis (HD) patients. We prospectively assess the long-term clinical, biochemical, and virological effects of interferon in the treatment of HD patients with chronic HCV infection. This study was performed in 20 HCV-RNA-positive HD patients with evidence of chronic hepatitis on liver biopsy. The patients received IFN administered after HD sessions in doses ranging from 3 to 6 million units for 6 to 12 months. The patients were followed up for a period of 6 years with determinations of serial alanine aminotransferase (ALT) levels and serum HCV-RNA. At the time of the final follow-up, the patients had no cirrhosis or hepatocellular carcinoma. Among the nonresponder group, only 1 patient died due to sudden cardiac death. Sustained normal serum ALT levels occurred in 9 (45%) of the patients. Nine patients had variable ALT levels, and 2 patients had persistently elevated ALT levels. Eight (40%) patients were continuously HCV-RNA negative, whereas 12 patients (60%) had variable HCV-RNA results at the end of the 6-year follow-up. These findings show that the long-term clinical, biochemical, and virological response to interferon monotherapy is good in HD patients with HCV infection.

Hepatitis C and renal transplantation: a review on historical aspects and current issues

Chronic liver disease has a significant impact on the survival of renal transplant recipients with an incidence rate of 4-38%. Approximately, 8-28% of renal transplant recipients die due to chronic liver disease. Hepatitis C seems to be the leading cause of chronic liver disease in kidney recipients. Hepatitis C virus (HCV) infection has a wide range of prevalence (2.6-66%) among renal transplant recipients living in different countries with great genotype diversity in different parts of the world. Nowadays, antiviral drugs are used for the management of hepatitis C. Because of graft-threatening effects of some antiviral drugs used in HCV-infected renal transplant recipients, we specifically focused on HCV treatment after renal transplantation. Treatment of post-renal transplantation chronic liver disease with INF and ribavirin remains controversial. Anecdotal reports on post-renal transplantation hepatitis C demonstrate encouraging findings. This review summarises the most current information on diagnosis, treatment, prognosis, complications as well as the new aspects of treatment in HCV-infected renal transplant recipients. HCV belongs to the family of Flaviviridae, genus Hepacivirus.

KDOQI US commentary on the KDIGO clinical practice guideline for the prevention, diagnosis, evaluation, and treatment of hepatitis C in CKD

KDIGO (Kidney Disease: Improving Global Outcomes) is an international initiative with a key mission of developing clinical practice guidelines in the area of chronic kidney disease (CKD). KDIGO recently published evidence-based clinical practice guidelines for the prevention, diagnosis, evaluation, and treatment of hepatitis C virus infection in individuals with CKD. The process of adaptation of international guidelines is an important task that, although guided by general principles, needs to be individualized for each region and country. Therefore, the National Kidney Foundation-Kidney Disease Outcomes Quality Initiative (KDOQI) convened a multidisciplinary group to comment on the application and implementation of the KDIGO guidelines for patients with CKD in the United States. This commentary summarizes the process undertaken by this group in considering the guidelines in the context of health care delivery in the United States. Guideline statements are presented, followed by a succinct discussion and annotation of the rationale for the statements. Research recommendations that are of particular interest to the United States are then summarized to highlight future areas of inquiry that would enable updating of the guidelines.

Hepatitis C virus and kidney disease

Hepatitis C virus (HCV) infection remains frequent in patients on renal replacement therapy and has an adverse impact on survival in infected patients on chronic hemodialysis as well as renal transplant (RT) recipients. Nosocomial spread of HCV within dialysis units continues to occur. HCV is also implicated in the pathogenesis of renal dysfunction often mediated by cryoglobulins leading to chronic kidney disease as well as impairing renal allograft function. The role of antiviral therapy for hepatitis C in patients with renal failure remains unclear. Monotherapy with conventional interferon (IFN) for chronic hepatitis C is probably more effective in dialysis than in non-uraemic patients but tolerance is lower. Limited data only are available about monotherapy with pegylated interferon and combination therapy (pegylated IFN plus ribavirin) for chronic HCV in the dialysis population. Clinical experience with antiviral therapy for acute HCV in dialysis population is encouraging. Interferon remains contraindicated post-RT because of concerns about precipitating graft dysfunction. Sustained viral responses obtained by antiviral therapy in renal transplant candidates are durable after renal transplantation and may reduce HCV-related complications after RT (post-transplant diabetes mellitus, HCV-related glomerulonephritis, and chronic allograft nephropathy).

HCV in patients with end-stage renal disease

Chronic hepatitis C virus (HCV) infection remains an important cause of liver disease in patients with end-stage renal disease (ESRD) and conversely, renal failure has a significant impact on morbidity and mortality throughout the natural history of chronic HCV and its treatment. With improved awareness within dialysis units of the potential for spread and the institution of preventative measures, the prevalence of HCV infection in the hemodialysis-dependent population has continued to decline since 1995. Use of HCV (+) donor kidneys is associated with an increase in the prevalence of liver disease, but when compared with continued hemodialysis, transplantation using these kidneys is associated with improved survival. Overall, survival in patients with chronic HCV infection appears to be better after renal transplantation when compared with maintenance hemodialysis, and transplant should be considered for these patients. Data support the use of interferon and the improved efficacy of pegylated interferon formulations for treatment of chronic HCV infection in ESRD patients, although tolerability continues to be troublesome. The newest and most promising data regarding the treatment of HCV in ESRD involve the combination of reduced dose ribavirin with interferon or pegylated interferon suggesting similar enhancements in sustained virologic response (SVR) as seen in non-ESRD patients, but caution is advised, as all studies to date used ribavirin plasma concentration monitoring in patient with ESRD. Finally, with regard to postrenal transplant treatment of HCV infection, there is no evidence to support treatment with interferon-based therapy and pretransplant treatment remains the best option whenever possible.

Antiviral therapy of hepatitis C in chronic kidney diseases: meta-analysis of controlled clinical trials

Hepatitis C virus (HCV) infection remains frequent in patients with chronic kidney disease and the detrimental role of HCV on survival is well-established in this population. Several authors have reported on efficacy and safety of antiviral therapy for hepatitis C in this polulation but there is no clear consensus on management. To evaluate efficacy and safety of antiviral therapy for hepatitis C in patients with chronic kidney disease, we performed a systematic review of the published medical literature and completed a meta-analysis of controlled clinical trials. The primary outcome was sustained virological response (as a measure of efficacy); the secondary outcome was drop-out rate (as a measure of tolerability). We used the random effects model of Der Simonian and Laird, with heterogeneity and sensitivity analyses. We identified 13 studies including 539 unique patients; 10 (76.9%) concerned patients on maintenance dialysis. Only prospective, controlled clinical trials were included. Pooling of study results showed a significant increase of viral response in study (patients treated with antiviral therapy) than control patients (patients who did not receive therapy), the pooled odds ratio (OR) of failure to obtain a sustained viral response was 0.081 [95% confidence intervals (CI), 0.029-0.230], P = 0.0001. The pooled OR of drop-out rate was significantly increased in study vs control patients, OR = 0.389 (95% CI, 0.155-0.957), P = 0.04. The studies were heterogeneous with regard to viral response and drop-out rate. In the subset of clinical trials (n = 6) involving only dialysis patients receiving interferon (IFN) monotherapy for chronic HCV, there was a significant difference in the risk of failure to obtain a sustained viral response (study vs control patients), OR = 0.054 (95% CI, 0.019; 0.150), P = 0.0001 (random-effects model). No significant (NS) heterogeneity was found (Q = 14.604, P = 1.0). No difference in the drop-out rate between study and control patients was shown, OR = 0.920 (95% CI, 0.367; 2.311), NS. This result being homogeneous (Q = 3.639, P = 0.388). Our meta-analysis showed that the viral response was greater in patients with chronic kidney disease who received antiviral therapy than controls. No difference in the drop-out rate between study and control patients occurred in the subgroup of dialysis patients on IFN monotherapy. These results support IFN-based therapy for hepatitis C in patients on maintenance dialysis.

Hepatitis C virus infection in haemodialysis and kidney transplant patients

Chronic infection with hepatitis C virus (HCV) is an important global health problem. The prevalence of HCV is significantly higher in haemodialysis and kidney transplant patients, as compared to the general population. In spite of the relatively milder liver disease activity reported in HCV-infected haemodialysis patients, HCV infection adversely affects survival. Likewise, HCV has a detrimental effect on both patient and graft survival after kidney transplantation. However, patient survival is significantly better with kidney transplantation compared to remaining on dialysis; therefore, HCV infection alone should not be a contraindication to transplantation. Combination antiviral therapy with pegylated interferon-alpha and low-dose ribavirin is currently evolving in haemodialysis patients. Interferon-alpha (standard/pegylated) is relatively contraindicated after kidney transplantation because of an increased risk of allograft rejection. Therefore, antiviral treatment of transplant candidates while on dialysis remains the best option and may avoid the risk of HCV-associated liver and renal disease after transplantation. Large multi-centre clinical trials are required in HCV-infected haemodialysis and kidney transplant patients in order to define optimal therapeutic strategies before and after transplantation.

[Chronic viral hepatitis and kidney failure]

Chronic viral hepatitis remains a major problem among patients with chronic renal failure. Hepatitis B and C viruses are frequent among dialysis patients and after renal transplantation and may significantly diminish the survival of both the patient and the graft. Hepatitis B and C viral infection in these patients is often characterized by normal transaminase levels despite viremia and progressive liver lesions. Liver biopsy remains essential for assessing the extent of liver disease. Cirrhosis is a contraindication to transplantation of only a kidney, because of elevated morbidity and mortality. A combined as liver-kidney transplantation may be considered. The best treatment of hepatitis infections is preventive: vaccination against the hepatitis B virus and attentive hygiene, especially to prevent nosocomial transmission. Among patients not awaiting transplant, antiviral treatment should be reserved for patients with active or even fibrotic liver disease. For hemodialysis patients awaiting kidney transplant: Alpha interferon is ineffective and poorly tolerated by dialysis patients. Lamivudine is effective and well tolerated, but its long-term efficacy and its optimal effective dose in dialysis patients remain unknown.

Interferon treatment in hemodialysis patients with chronic hepatitis C virus infection: a systematic review of the literature and meta-analysis of treatment efficacy and harms

BACKGROUND

Hepatitis C virus (HCV) infection is prevalent in patients undergoing hemodialysis and is associated with greater mortality. We determined the efficacy and harms of interferon (IFN) and pegylated IFN (PEG-IFN) treatment of hemodialysis patients with chronic HCV infection and identified factors associated with these outcomes.

STUDY DESIGN

Meta-analysis and meta-regression of randomized controlled trials, uncontrolled trials, and prospective observational studies.

SETTING & POPULATION

Hemodialysis patients with chronic HCV infection.

SELECTION CRITERIA FOR STUDIES

MEDLINE indexed studies since 1966, sample size greater than 10.

INTERVENTION

IFN-based treatment, including PEG-IFN with and without ribavirin.

OUTCOMES

Sustained virological response (SVR) 6 months after treatment, rate of treatment discontinuation caused by adverse events, and factors associated with these outcomes.

RESULTS

20 studies of 459 IFN-treated patients, 3 studies of 38 PEG-IFN-treated patients, and 2 studies of 49 PEG-IFN and ribavirin-treated patients met inclusion criteria. The overall SVR rate was 41% (95% confidence interval [CI], 33 to 49) for IFN and 37% (95% CI, 9 to 77) for PEG-IFN. Treatment discontinuation rates were 26% (95% CI, 20 to 34) for IFN and 28% (95% CI, 12 to 53) for PEG-IFN. SVR was higher with 3 million units (MU) or higher of IFN 3 times weekly, with lower mean HCV RNA, and with lower rates of cirrhosis, HCV genotype 1 or elevated transaminase, but these findings were not statistically significant. Treatment discontinuation rates were greater in studies using larger doses.

LIMITATIONS

Publication bias, few randomized controlled trials, and limitations in generalizability to all hemodialysis patients.

CONCLUSION

IFN treatment of hemodialysis patients results in an SVR rate of 41%. Higher dose, lower mean HCV RNA level, and lower rates of cirrhosis, transaminase level increase, and HCV genotype 1 may be associated with greater SVR rates, but additional studies using individual patient data are needed.

Interferon monotherapy of chronic hepatitis C in dialysis patients: meta-analysis of clinical trials

The efficacy of monotherapy with interferon (IFN) (conventional or pegylated IFN) in dialysis patients with chronic hepatitis C remains unclear, although a number of clinical trials have been published addressing this issue. The aim of the study was to evaluate the efficacy and safety of monotherapy by conventional or pegylated IFN in dialysis patients with chronic hepatitis C by performing a systematic review of the literature with a meta-analysis of clinical trials. The primary outcome was sustained virological response (SVR; as a measure of efficacy), and the secondary outcome was drop-out rate (as a measure of tolerability). We used the random-effects model of Der Simonian and Laird, with heterogeneity and sensitivity analyses. We identified 28 clinical trials (645 unique patients), of which six (21.4%) had a controlled design. In the group of trials based on conventional IFN, the summary estimate for SVR and drop-out rate was 39% [95% confidence interval (CI) 32-46] and 19% (95% CI 13-26) respectively. The summary estimate for SVR rate in patients with the hepatitis C virus genotype 1 was 33% (95% CI 19-47). In the subset of trials using pegylated IFN, the summary estimate for SVR and drop-out rate was 31% (95% CI 7-55) and 27% (95% CI 1-52) respectively. The most frequent side-effects requiring interruption of treatment were flu-like symptoms, and gastrointestinal and haematological changes. A relationship between age and drop-out rate was found, even if no statistical significance was reached (P = 0.064). The studies were heterogeneous with regard to SVR and drop-out rate. No publication bias was observed. One-third of dialysis patients with chronic hepatitis C were successfully treated with conventional or pegylated IFN monotherapy. Preliminary evidence does not support additional benefit due to monotherapy with pegylated IFN on the viral response in the chronic kidney disease (CKD) population. Tolerance to IFN monotherapy was unsatisfactory, particularly to pegylated IFN. The optimal antiviral treatment of chronic hepatitis C in dialysis populations is currently under active investigation.

Treatment of HCV in patients with renal failure

There continues to be a high prevalence of hepatitis C virus infection in patients with chronic kidney disease (CKD) on maintenance hemodialysis, despite screening of blood products and precautions to prevent the transmission of viral hepatitis within dialysis units. In addition, an increased rate of mortality from liver disease has been observed in infected patients on long-term dialysis, despite the frequent absence of biochemical dysfunction. Hepatitis C-infected renal transplant recipients have diminished patient and graft survivals compared to uninfected controls. Treatment with interferon in renal transplant candidates has resulted in sustained viral responses that have been long lasting even after subsequent renal transplant. A major concern limiting the use of interferon following renal transplant is graft dysfunction due to rejection. Ribavirin's induction of hemolytic anemia is the major reason why it is avoided in patients with CKD. Cautious use of reduced-dose ribavirin in small studies has been promising in these patients with close monitoring of hematocrit and additional measures to enhance compensatory erythropoiesis.

Treatment of hepatitis C virus infection (HCV) after renal transplantation: implications for HCV-positive dialysis patients awaiting a kidney transplant

Patient survival is significantly lower in hepatitis C virus (HCV)-positive compared to HCV-negative dialysis patients. After renal transplantation, immunosuppressive therapy can result in an increased burden of HCV viremia. Both patient and graft survivals are lower in HCV-positive compared to matched HCV-negative renal-transplant patients. Therefore, it is important to treat HCV infection. At present, after renal transplantation, there is no current safe and efficient therapy. Alpha-interferon (alpha-IFN) does not give a sustained virological response, and is associated with a high rate of renal failure. Ribavirin and amantadine monotherapies are associated with a significant improvement in liver enzymes, but have no impact upon HCV viremia. Ribavirin, however, may be indicated in cases of HCV-related glomerulopathy because it can significantly decrease proteinuria. The combined use of alpha-IFN and ribavirin should only be given to those patients who have developed posttransplant fibrosing cholestatic hepatitis. Therefore, HCV infection needs to be treated pretransplant. In dialysis patients, the only recommended therapy, as yet, is alpha-IFN monotherapy. Pegylated alpha-IFN is under evaluation and ribavirin is contraindicated because it results in severe hemolytic anemia. Twelve months of alpha-IFN therapy results in sustained virological clearance in approximately 40% of patients, regardless of their genotype. HCV RNA, after three months of alpha-IFN therapy, is a predictive factor for a long-term sustained response. Finally, when HCV-positive dialysis patients with a sustained virological response undergo successful renal transplantation, very few suffer a virological relapse, thus emphasizing that these patients were cured.

Hepatitis C in transplant recipients of solid organs, other than liver

Hepatitis C virus (HCV) infection is prevalent in candidates for, and recipients of, solid organ transplants. HCV infection can lead to diminished patient and allograft survival in the long-term in recipients of kidney transplants. Outcomes in recipients of other solid organ transplants (lung, heart, small bowel, pancreas, pancreas-kidney) are not well established. Large, well-designed, prospective studies are needed to answer these questions. Interferon therapy for HCV before transplantation can lead to improved outcomes. Therefore, transplant candidates should be considered for and offered interferon therapy before embarking on organ transplantation. Posttransplant interferon therapy can be complicated by acute allograft rejection and is not recommended, except with advanced liver disease.

Acute renal allograft rejection following pegylated IFN-alpha treatment for chronic HCV in a repeat allograft recipient on hemodialysis: a case report

Interferon alpha (IFN-alpha) can be effective therapy for patients with chronic kidney disease who have chronic hepatitis C (HCV). However, acute allograft rejection has been reported in association with IFN-alpha following kidney transplantation, and therefore IFN therapy is recommended prior to, rather than after, kidney transplantation whenever feasible. The special case of repeat allograft recipients who contract HCV after the first transplantation presents special difficulties. This report features the case of a repeat allograft recipient who presented with neutropenic fevers after 5 months of pegylated IFN-alpha therapy, initiated 6 months following the functional loss of his third graft and the reinitiation of hemodialysis (HD). Physical exam, radiographic and laboratory findings led to allograft nephrectomy. The pathologic findings supported a diagnosis of acute-on-chronic rejection. This represents a rare case of IFN-alpha induced rejection following allograft failure and return to HD in a repeat allograft recipient. It also calls attention to the need for a high index of suspicion for the development of allograft rejection, which may require allograft nephrectomy even after allograft 'failure'.

Efficacy and tolerance of interferon-alpha in the treatment of chronic hepatitis C in end-stage renal disease patients on hemodialysis

BACKGROUND

Patients with end-stage renal disease (ESRD) show a high prevalence of hepatitis C, with a negative impact on the survival on hemodialysis and after renal transplantation. We evaluated the efficacy and tolerance of interferon-alpha (IFN-alpha) in HCV-infected ESRD patients on dialysis.

METHODS

Forty-six HCV-RNA-positive ESRD patients were studied. IFN-alpha regimen consisted of 3 million units three times a week for 12 months, and the patients were followed up for 6 months. End-of-treatment, and sustained biochemical and virological responses were evaluated and tolerance was assessed monthly.

RESULTS

A sustained virological response (SVR) was observed in 10/46 patients (22%) and in 10/29 who completed the treatment (34%). Alanine aminotransferase was elevated in 63% of the patients at the beginning of the study and returned to normal levels within the first month in all patients with SVR. Treatment was discontinued because of side effects in 11/46 patients (24%) and six patients (13%) were lost to follow-up.

CONCLUSIONS

IFN-alpha monotherapy for hepatitis C in dialysis patients shows a high frequency of adverse effects. However, the SVR is high (34%) in patients who complete treatment, emphasizing the importance of careful selection and close follow-up in order to minimize and control possible side effects.

Chronic viral hepatitis in hemodialysis patients

Ever since the first outbreaks of hepatitis in hemodialysis units in the late 1960s, a number of hepatotropic viruses transmitted by blood and other body fluids have been identified. This review summarizes the current state of knowledge regarding these blood-borne agents from an epidemiologic and preventive perspective. Data source and study selection were obtained from research and review articles related to the epidemiology of viral hepatitis in hemodialysis and indexed on Medline and Embase from 1965 to 2004. Hepatitis B virus (HBV) was the first significant hepatotropic virus to be identified in hemodialysis centers. HBV infection has been effectively controlled by active vaccination, screening of blood donors, the use of erythropoietin, and segregation of HBV carriers. To date, HBV remains an important cause of morbidity in endemic areas. Hepatitis delta virus is a defective virus that can only infect HBV-positive individuals. Hepatitis C virus is the most significant cause of non-A, non-B hepatitis and is mainly transmitted by blood transfusion. The introduction in 1990 of routine screening of blood donors for HCV contributed significantly to the control of HCV transmission. An effective HCV vaccine remains an unsolved challenge, however. Pegylation of interferon-alpha has made it possible to treat HCV-positive dialysis patients. Unexplained sporadic outbreaks of hepatitis by the mid-1990s prompted the discovery of hepatitis G virus and hepatitis GB virus C in 1995 and the TT virus in 1997. Although epidemiologic analyses revealed high prevalence rates of both viruses in the hemodialysis population, their exact role in liver disease has yet to be determined. The vigilant observation of guidelines on universal precaution and regular virologic testing are the cornerstones of the effective control of chronic hepatitis in the setting of hemodialysis.

Hepatitis B virus infection in dialysis patients

Hepatitis B virus (HBV) infection remains a major issue among dialysis patients. It is associated with a high risk of hepatic complication. The liver disease runs a unique clinical course in dialysis patients, as it can progress with modest hepatic inflammation and prominent fibrosis. The conventional cut-off level of serum alanine aminotransferase (ALT) for commencing antiviral therapy may prove too high and inappropriate for dialysis patients, and liver biopsy appears to be the only definitive means to establish the activity of liver disease in dialysis patients. Liver biopsy should be considered in patients with a serum ALT level that is persistently greater than 30 IU/L, or 0.75-fold the upper limit of the normal level, and/or other clinical and laboratory findings that suggest active liver disease. For antiviral treatment, preliminary reports have shown that lamivudine is effective and well tolerated in dialysis patients. However, the long-term efficacy of lamivudine and its optimal effective dose in dialysis patients remain unknown. The prevention of nosocomial transmission among dialysis patients is also important. Universal precaution measures should be strictly observed and the segregation of hepatitis B surface antigen-positive hemodialysis patients should be considered. For HBV non-immune patients, the importance of HBV vaccination should not be overemphasized. Until a new generation of highly immunogenic vaccines that are proven to be safe and effective in patients with end-stage renal disease becomes available, early vaccination before the development of end-stage renal failure remains the best way to secure immunological protection against HBV infection in dialysis patients.