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

Evaluation of Long-Term Outcomes of Direct Acting Antiviral Agents in Chronic Kidney Disease Subjects: A Single Center Cohort Study

BACKGROUND

The chronic kidney disease (CKD) population, including kidney transplant recipients (KTRs) and subjects on renal replacement therapy, is particularly vulnerable to unfavorable outcomes from chronic hepatitis C (CHC). Currently, there are oral direct-acting antiviral agents (DAAs) available to eradicate the virus with favorable short-term outcomes; however, their long-term effects are lacking. The aim of the study is to assess the long-term efficacy and safety of DAA therapy in the CKD population.

METHODS

An observational, cohort single-center study was performed. Fifty-nine CHC subjects with CKD, treated with DAAs between 2016 and 2018, were enrolled in the study. Safety and efficacy profiles were assessed, including sustained virologic response (SVR), occult hepatitis C infection (OCI) incidence, and liver fibrosis.

RESULTS

SVR was achieved in 96% of cases (n = 57). OCI was diagnosed only in one subject following SVR. Significant liver stiffness regression was observed 4 years after SVR compared to baseline values (Mdn = 6.1 kPa, IQR = 3.75 kPa; 4.9 kPa, IQR = 2.9 kPa), p < 0.001. The most common adverse events were anemia, weakness, and urinary tract infection.

CONCLUSION

DAAs provide a safe and effective cure for CHC in both CKD patients and KTRs with a favorable safety profile in the long-term follow-up.

The Use of Biomarkers in Pharmacovigilance: A Systematic Review of the Literature

Background

The use of biomarkers varies from disease etiognosis and diagnosis to signal detection, risk prediction, and management. Biomarker use has expanded in recent years, however, there are limited reviews on the use of biomarkers in pharmacovigilance and specifically in the monitoring and management of adverse drug reactions (ADRs).

Objective

The objective of this manuscript is to identify the multiple uses of biomarkers in pharmacovigilance irrespective of the therapeutic area.

Design

This is a systematic review of the literature.

Data Sources and Methods

Embase and MEDLINE database searches were conducted for literature published between 2010-March 19, 2021. Scientific articles that described the potential use of biomarkers in pharmacovigilance in sufficient detail were reviewed. Papers that did not fulfill the United States Food and Drug Administration (US FDA) definition of a biomarker were excluded, which is based on the International Conference on Harmonisation (ICH)-E16 guidance.

Results

Twenty-seven articles were identified for evaluation. Most articles involved predictive biomarkers (41%), followed by safety biomarkers (38%), pharmacodynamic/response biomarkers (14%), and diagnostic biomarkers (7%). Some articles described biomarkers that applied to multiple categories.

Conclusion

Various categories of biomarkers including safety, predictive, pharmacodynamic/response, and diagnostic biomarkers are being investigated for potential use in pharmacovigilance. The most frequent potential uses of biomarkers in pharmacovigilance in the literature were the prediction of the severity of an ADR, mortality, response, safety, and toxicity. The safety biomarkers identified were used to evaluate patient safety during dose escalation, identify patients who may benefit from further biomarker testing during treatment, and monitor ADRs.

Estimating the causal effect of treatment with direct-acting antivirals on kidney function among individuals with hepatitis C virus infection

Background

Direct-acting antivirals (DAA) are highly effective at treating Hepatitis C virus (HCV) infection, with a cure rate >95%. However, the effect of DAAs on kidney function remains debated.

Methods

We analyzed electronic health record data for DAA-naive patients with chronic HCV infection engaged in HCV care at Boston Medical Center between 2014 and 2018. We compared the following hypothetical interventions using causal inference methods: 1) initiation of DAA and 2) no DAA initiation. For patients with normal kidney function at baseline (eGFR>90 ml/min/1.73m²), we estimated and compared the risk for reaching Stage 3 chronic kidney disease (CKD) (eGFR≤60 ml/min/1.73m²) under each intervention. For patients with baseline CKD Stages 2–4 (15<eGFR≤90 ml/min/1.73m²), we estimated and compared the mean change in eGFR at 2 years after baseline under each intervention. We used the parametric g-formula to adjust our estimates for baseline and time-varying confounders.

Results

First, among 1390 patients with normal kidney function at baseline the estimated 2-year risk difference (95% CI) of reaching Stage 3 CKD for DAA initiation versus no DAA was -1% (-3, 2). Second, among 733 patients with CKD Stage 2–4 at baseline the estimated 2-year mean difference in change in eGFR for DAA initiation versus no DAA therapy was -3 ml/min/1.73m² (-8, 2).

Conclusions

We found no effect of DAA initiation on kidney function, independent of baseline renal status. This suggests that DAAs may not be nephrotoxic; furthermore, in the short-term, HCV clearance may not improve CKD.

Liver fibrosis improvement in chronic hepatitis C after direct acting-antivirals is accompanied by reduced profibrogenic biomarkers-a role for MMP-9/TIMP-1

BACKGROUND AND AIMS

Disturbances in matrix metalloproteinases (MMPs) and corresponding tissue inhibitors (TIMPs) contribute to hepatitis C virus (HCV)-induced fibrosis. This study aimed to determine MMP-9/TIMP-1 levels in addition to MMP-2 and -9 activities; correlating with the improvement of liver fibrosis in patients under direct-acting antiviral (DAA) therapy.

METHODS

Clinical and laboratory follow-up were performed before treatment and after 12 weeks post-treatment, referred as sustained viral response (SVR). We evaluated liver function including non-invasive fibrosis measurements; MMP activity by zymography; and MMP-9/TIMP-1 complex, inflammatory and pro-fibrogenic mediators by immunoenzymatic assays.

RESULTS

Cohort included 33 patients (59.5 ± 9.3 years, 60.6% females) whose reached SVR and 11 control-paired subjects (42.5 ± 15 years, 54.5% females). Before treatment, HCV patients presented higher MMP-9/TIMP-1 levels (P < 0.05) when compared to controls, and the highest values were observed in patients with fibrosis (P < 0.05). In addition, MMP-9/TIMP-1 levels were significantly reduced after DAA therapy (P < 0.0001) and were associated with profibrogenic biomarkers. No differences were observed for MMP-2 and -9 activities; however, these biomarkers were significantly associated with inflammatory mediators.

CONCLUSION

Our data suggest that MMP-9/TIMP-1 complex can be a promising biomarker of active fibrogenesis, being able to identify the interruption of fibrosis progression after HCV eradication.

HEPATITIS C TREATMENT OF RENAL TRANSPLANT AND CHRONIC KIDNEY DISEASE PATIENTS: EFFICACY AND SAFETY OF DIRECT-ACTING ANTIVIRAL REGIMENS CONTAINING SOFOSBUVIR

BACKGROUND

Direct-acting antivirals have revolutionized hepatitis C treatment, also for patients with chronic kidney disease (CKD), but some controversy exists regarding the use of sofosbuvir (SOF) in patients with glomerular filtration rate (GFR) <30 mL/min.

OBJECTIVE

To evaluate the efficacy and safety of these regimens for hepatitis C treatment of patients with CKD and after renal transplantation, as well as the impact of SOF on renal function in non-dialysis patients.

METHODS

All patients with hepatitis C and CKD or renal transplant treated with direct-acting antivirals at a referral center in Brazil between January 2016 and August 2017 were included. Efficacy was evaluated based on viral load (HCV RNA) and a sustained virological response (SVR) consisting of undetectable RNA 12 and/or 24 weeks after the end of treatment (SVR12 and SVR24) was defined as cure. Safety was determined by adverse events and ribavirin, when combined, was administered in escalating doses to all patients with GFR <60 mL/min. The impact of SOF on renal function was determined by the measurement of baseline creatinine during and after the end of treatment and its increase was evaluated using the Acute Kidney Injury Network (AKIN) classification.

RESULTS

A total of 241 patients (52.7% females) with a mean age of 60.72±10.47 years were included. The combination of SOF+daclatasvir was the predominant regimen in 75.6% of cases and anemia was present in 28% of patients who used ribavirin (P=0.04). The SVR12 and SVR24 rates were 99.3% and 97.1%, respectively. The treatment was well tolerated and there were no major clinically relevant adverse events, with the most prevalent being asthenia (57.7%), itching (41.1%), headache (40.7%), and irritability (40.2%). Among conservatively treated and renal transplant patients, oscillations of creatinine levels (AKIN I) were observed in 12.5% of cases during treatment and persisted in only 8.5% after the end of treatment. Of these, 2.0% had an initial GFR <30 mL/min and this percentage decreased to 1.1% after SOF use. Only 0.5% and 1.6% of the patients progressed to AKIN II and AKIN III elevation, respectively.

CONCLUSION

The direct-acting antivirals were safe and efficacious in CKD patients treated with SOF-containing regimens, with the observation of high SVR rates, good tolerability and few severe adverse events. The combination with ribavirin increased the risk of anemia and the administration of escalating doses seems to be useful in patients with GFR <60 mL/min. In patients with GFR <30 mL/min, SOF had no significant renal impact, with serum creatinine returning to levels close to baseline after treatment.

Direct-acting antiviral therapy slows kidney function decline in patients with Hepatitis C virus infection and chronic kidney disease

Hepatitis C virus (HCV) infection is common and can accelerate chronic kidney disease (CKD) progression. Direct-acting antiviral (DAA) therapies against hepatitis C have consistently shown rates of sustained viral remission. However, the effect on kidney function is unknown. In a retrospective observational cohort study of HCV-infected patients receiving DAA therapies from 2013 to 2017, the slopes of estimated glomerular filtration rate (eGFR) decline were compared in the three years before DAA therapy to the slope after therapy. Pre- and post-treatment albuminuria values were also compared. In all, 1,178 patients were included; mean age of 56, 64% male, 71% white, 21% were diabetic, and 42% with cirrhosis. In patients with eGFR less than 60ml/min per 1.73m2, the annual decline in eGFR in the three years prior to treatment was -5.98 ml/min per year (95% confidence interval -7.30 to -4.67) and improved to -1.32 ml/min per year (95% confidence interval -4.50 to 1.88) after DAA therapy. In patients with eGFR greater than 60ml/min per 1.73m2 the annual decline in eGFR in the three years prior to treatment was -1.43 ml/min per year (95% confidence interval -1.78 to -1.08) and after DAA therapy was -2.32 ml/min per year (95% confidence interval -3.36 to -1.03). Albuminuria improved significantly in patients without diabetes, but not in those with diabetes. Predictors of eGFR improvement included having CKD at baseline and being non-diabetic. Events of acute kidney injury were rare, occurring in 29 patients, and unrelated to antiviral therapy in 76% of cases. Thus, DAA therapy for HCVs infection may slow CKD progression.

Treating hepatitis C virus in dialysis patients: How, when, and why?

The identification of hepatitis C virus (HCV) occurred in 1989, and soon thereafter, it was recognized that there was a higher prevalence of anti-HCV seropositivity in patients with end-stage renal disease (ESRD) when compared to the general population. Multiple extrahepatic manifestations have been associated with HCV infection in patients with ESRD; these include an increased prevalence and risk of cardiovascular complications, insulin resistance, diabetes mellitus, and lymphoproliferative disorders. Infection with HCV has also been associated with an increased relative risk of mortality in the ESRD patient when contrasted to those patients without infection. The availability of second-generation direct-acting antiviral agents has revolutionized the treatment of HCV in both the general population as well as those patients with advanced chronic kidney disease and receiving dialysis. These new treatment protocols are very well tolerated with limited side effects and manageable drug-drug interactions while achieving remarkable sustained viral response rates. It is important that nephrologists become familiar with the differing strategies available for HCV-infected ESRD patients so that the appropriate decision of when and who to treat can be made for each patient.