Direct-Acting Antivirals in Kidney Transplant Patients: Successful Hepatitis C Treatment and Short-Term Reduction in Urinary Protein/Creatinine Ratios

UAB-UCSD O'Brien Center for Acute Kidney Injury Research

Acute kidney injury (AKI) remains a significant clinical problem through its diverse etiologies, the challenges of robust measurements of injury and recovery, and its progression to chronic kidney disease (CKD). Bridging the gap in our knowledge of this disorder requires bringing together not only the technical resources for research but also the investigators currently endeavoring to expand our knowledge and those who might bring novel ideas and expertise to this important challenge. The University of Alabama at Birmingham-University of California-San Diego O'Brien Center for Acute Kidney Injury Research brings together technical expertise and programmatic and educational efforts to advance our knowledge in these diverse issues and the required infrastructure to develop areas of novel exploration. Since its inception in 2008, this O'Brien Center has grown its impact by providing state-of-the-art resources in clinical and preclinical modeling of AKI, a bioanalytical core that facilitates measurement of critical biomarkers, including serum creatinine via LC-MS/MS among others, and a biostatistical resource that assists from design to analysis. Through these core resources and with additional educational efforts, our center has grown its investigator base to include >200 members from 51 institutions. Importantly, this center has translated its pilot and catalyst funding program with a $37 return per dollar invested. Over 500 publications have resulted from the support provided with a relative citation ratio of 2.18 ± 0.12 (iCite). Through its efforts, this disease-centric O'Brien Center is providing the infrastructure and focus to help the development of the next generation of researchers in the basic and clinical science of AKI. This center creates the promise of the application at the bedside of the advances in AKI made by current and future investigators.

Tomoelastography for Longitudinal Monitoring of Viscoelasticity Changes in the Liver and in Renal Allografts after Direct-Acting Antiviral Treatment in 15 Kidney Transplant Recipients with Chronic HCV Infection

Besides the liver, hepatitis C virus (HCV) infection also affects kidney allografts. The aim of this study was to longitudinally evaluate viscoelasticity changes in the liver and in kidney allografts in kidney transplant recipients (KTRs) with HCV infection after treatment with direct-acting antiviral agents (DAAs). Fifteen KTRs with HCV infection were treated with DAAs (daclatasvir and sofosbuvir) for 3 months and monitored at baseline, end of treatment (EOT), and 3 (FU1) and 12 (FU2) months after EOT. Shear-wave speed (SWS) and loss angle of the complex shear modulus (φ), reflecting stiffness and fluidity, respectively, were reconstructed from multifrequency magnetic resonance elastography data with tomoelastography post-processing. After virus elimination by DAAs, hepatic stiffness and fluidity decreased, while kidney allograft stiffness and fluidity increased compared with baseline (hepatic stiffness change at FU1: -0.14 m/s, p < 0.01, and at FU2: -0.11 m/s, p < 0.05; fluidity at FU1: -0.05 rad, p = 0.04 and unchanged at FU2: p = 0.20; kidney allograft stiffness change at FU1: +0.27 m/s, p = 0.01, and at FU2: +0.30 m/s, p < 0.01; fluidity at FU1 and FU2: +0.06 rad, p = 0.02). These results suggest the restoration of mechanically sensitive structures and functions in both organs. Tomoelastography can be used to monitor the therapeutic results of HCV treatment non-invasively on the basis of hepatic and renal viscoelastic parameters.

Direct Acting Antivirals in Hepatitis C-Infected Kidney Transplant Recipients: Associations with Long-term Graft Failure and Patient Mortality

Background

Direct-acting antiviral (DAA) therapy among hepatitis C virus (HCV)-infected kidney transplant recipients is associated with short-term improvement in protein/creatinine (P/C) ratios, but how HCV cure affects long-term graft outcomes remains unknown.

Methods

This is a retrospective follow-up study of 59 HCV-infected patients who underwent kidney transplant at the University of Alabama at Birmingham between 2007-2015 who were followed until the end of 2017. We examined the association of DAA-induced HCV cure with graft failure or death by survival analyses (Kaplan-Meier, Cox regression).

Results

Mean age was 55 years, 73% were African American, and 68% were male. Median baseline creatinine was 1.4 mg/dL, P/C ratio was 0.5, and estimated glomerular filtration rate (eGFR) was 59 mL/min. Of those who received DAA, 24 (83%) achieved cure. The remaining 5 DAA patients (17%) did not have documented evidence of sustained virologic response (SVR). Overall, 19 (32%) patients experienced graft failure or death; with lower incidence in treated patients than untreated (4 vs 15 events; 2.6 vs 10.3 per 100 person-years [cHR 0.19, 95% CI: 0.06-0.66]). When adjusted for age, sex, race, and proteinuria, the association remained strong and invariant across time-varying (aHR 0.30, 95% CI: 0.08-1.10), time-averaged (aHR 0.28, 95% CI: 0.07-1.07), and time-varying-cumulative (aHR 0.32, 95% CI: 0.08-1.21) proteinuria metrics.

Conclusions

DAAs therapy was associated with improved graft survival and reduced mortality. While not statistically significant, the association was strong, and these single-center findings warrant larger studies to demonstrate the benefits of HCV treatment in this population.

Direct acting antiviral HCV treatment does not influence renal function

HCV infection is associated with chronic kidney disease due to several mechanisms. Patients treated with interferon-based regimens demonstrate improved renal function and reduced incidence of chronic kidney disease. There is scarce evidence on the effect of direct acting antiviral regimens (DAAs) on renal function.We evaluated serial measures of renal function in a cohort of HCV-infected participants following completion of DAA-based treatment regimens.Measures of glomerular filtration rate (GFR) were estimated by the CKD-EPI equation. Data was recorded at end of treatment, and at 6-12 months, 12-24 months, and greater than 24 months following treatment completion. Group-based trajectory modeling was used to determine distinct GFR trajectories. Predictors of group membership were determined by multinomial regression analysis.Six trajectories were identified. One trajectory comprising 27% of the cohort demonstrated declining renal function and the others demonstrated no change in renal function over time. Baseline GFR did not predict SVR. Diabetes was associated with lower post-treatment GFR but patients with diabetes did not demonstrate a decrease in GFR over the period of evaluation. Cirrhosis and SVR were not significant predictors of GFR or GFR trajectory.There is no clinically relevant change in renal function among the majority of HCV-infected patients following completion of DAA-based treatments. Renal function does not influence the efficacy of DAA-based regimens. No consistent effect of DAA treatment and/or SVR on renal function was observed over a 2-year period following treatment completion.

Long-term follow-up of HCV infected kidney transplant recipients receiving direct-acting antiviral agents: a single-center experience in China

Background

Long-term outcome of DAAs therapy in kidney transplant recipients was unknown. Thus, we aimed to evaluate it in a Chinese cohort of HCV-infected kidney transplant recipients.

Methods

Single-center and retrospective study of HCV-infected kidney transplant recipients initiating an DAAs regimen between January 2015 and December 2017 was conducted. Totally 26 KTX recipients were divided into three groups, including KTX-HD Group, DAA-KTX Group and KTX-DAA Group. On-treatment response was defined as target not detected within 12 weeks. SVR 48, 96 were defined as HCV-RNA negativity 48, 96 weeks after treatment cessation, respectively.

Results

HCV genotype was predominantly 1b (80.8%), followed by 2a. All (100%) patients achieved on-treatment response. Time to first TnD was 1.9 ± 0.6 weeks, with no significant difference among the three groups. All patients achieved SVR, with an SVR rate of 100.0% (26/26) among the patients who were followed up over 48 weeks after treatment cessation, and the same SVR rate (24/24) among the patients who were followed up over 96 weeks. Trough levels of Tac remained stable under DAAs therapy, without any dose adjustment. Two patients with abnormal GFR before treatment experienced serum creatinine elevation. Other adverse events included nausea, diarrhea, acid regurgitation, bilirubin elevation and edema of lower limbs. All patients recovered after treatment cessation without reductions in dose, or withdrawal of DAAs or immunosuppressive agents.

Conclusions

HCV genotype 1b and 2a are the only genotypes and 1b is predominant in our center. Antiviral treatment with DAAs in HCV-infected kidney transplant recipients is persistently effective and well tolerated during long-term follow-up. A regular monitoring of renal function in patients who receive DAAs regimens with preexisting impaired renal function is strongly recommended. Furthermore, the trough CNIs levels were recommended to be frequently monitored.

Hepatitis C virus infection in kidney transplantation-changing paradigms with novel agents

Hepatitis C virus (HCV) is a common cause of increased morbidity and mortality in kidney transplant patients. It is associated with posttransplant glomerulonephritis, chronic allograft nephropathy, and New Onset Diabetes after Transplant (NODAT). In the past, HCV was difficult to treat due to the presence of interferon alpha-based therapies that were difficult to tolerate and were associated with adverse side-effects, such as the risk of rejection. With the advent of oral directly acting antiviral therapies, the landscape for HCV and transplantation has changed. These agents are highly effective and well tolerated with minimal side-effects. Sustained viral response rates in excess of 90% are achieved with most current treatment regimens active against all HCV genotypes. These new agents may show an improvement in graft and patient survival while essentially eliminating the risk of acute rejection from the use of prior interferon-based HCV therapies. These agents may also result in an improvement in organ allocation for HCV donor/HCV recipient transplantation. This review is meant to discuss the epidemiology of HCV, the new oral direct-acting antiviral agents (DAAs) and future opportunities for research in the field of HCV related transplantation.

Renal safety after one year of sofosbuvir-based therapy for chronic hepatitis C: A Brazilian "real-life" study

WHAT IS KNOWN AND OBJECTIVE

Sofosbuvir(SOF)-based regimens have been administrated with excellent efficacy in chronic hepatitis C. Few uncontrolled ("real-life") studies consider the assessment of renal function when evaluating their post-treatment outcomes. This study aims to evaluate renal biomarkers in a "real-life" experience with chronic hepatitis C patients treated with SOF therapy in a long-term follow-up.

METHODS

Serum and urinary biomarkers were analysed before, at the end of therapy (EoT), after 12 weeks (sustained virological response-SVR) and one year (1y) post-treatment. Patients were categorized according to baseline glomerular filtration rate (GFR-cut-off 45 mL/min/1.73 m² ).

RESULTS

Ninety-four patients with a mean age of 59.9 ± 8.5 years were included; 98.9% of patients reached SVR. Significant improvement in renal biomarkers was observed in patients with GFR ≥45 mL/min/1.73 m² , as indicated by a progressive increase in mean GFR values until 1y. No evidence of tubular dysfunction was identified. Patients with baseline GFR <45 mL/min/1.73 m² did not experience alterations in renal biomarkers; however, a mean change of +10.7 in GFR values was observed. We noticed significant upper stage transition in the CKD classification, and 58.7% of patients achieved G1 stage at 1y (P < .0001).

WHAT IS NEW AND CONCLUSION

In a "real-life experience" of a Brazilian centre, SOF therapy appears to guarantee renal safety for patients with chronic hepatitis C followed until one year after treatment.

Hepatitis C Virus Treatment in Patients With Chronic Kidney Disease and in Kidney Transplant Recipients

An important interplay exists between hepatitis C virus (HCV) infection and chronic kidney disease (CKD). HCV infection is associated with an increased risk of morbidity and mortality in patients coinfected with CKD, and patients with CKD have an increased risk of HCV infection. Direct-acting antiviral (DAA) agents have changed the landscape of treatment with excellent sustained virologic response rates and fewer side effects than previously seen. An increasing number of studies demonstrate that DAA agents are efficacious and safe both in patients on dialysis and in patients who have undergone kidney transplantation. This article reviews the current literature on approved DAA agents for the treatment of HCV infection in patients on dialysis and in kidney transplant recipients.