Effects of Entecavir and Tenofovir on Renal Function in Patients with Hepatitis B Virus-Related Compensated and Decompensated Cirrhosis

Evaluation of Pharmacokinetics of a BCS Class III Drug with Two Different Study Designs: Tenofovir Alafenamide Monofumarate Film-coated Tablet

Tenofovir alafenamide (TAF) is a BCS Class III compound and an oral pro-drug of Tenofovir (TFV) with limited oral bioavailability. The bioavailability of the oral intake increases with food as a result of the low stability of the active substance in the stomach. The reference drug is "Vemlidy® 25 mg Film Tablet", which contains 25 mg of TAF in "hemifumarate" form, is under patent protection until 15.08.2032 by Gilead, and so the "monofumarate" form was used in the present study. At first, a pilot study was conducted involving 12 subjects under fed conditions. The results of the pilot study revealed the test and reference products were not bioequivalent, as a result of insufficient statistical power and high inter-subject variability. Secondly, a physiologically based pharmacokinetic (PBPK) simulation was performed based on the pilot study results and literature data. Finally, the power of the design was increased and the pivotal study design was optimized into a four-period, full-replicated, cross-over study with 34 subjects under fed conditions and it was concluded that the test and reference products were bioequivalent. In conclusion, the present study proved the importance of a correct study design with higher statistical power for a BCS Class III compound with high variability, to present the pharmacokinetics.

Renal dysfunction during treatment of chronic hepatitis B with tenofovir disoproxyl fumarate and associated risk factors

OBJECTIVES

To analyze the evolution of glomerular filtration rate (GFR) and the presence of renal tubular dysfunction during the treatment of chronic hepatitis B virus (HBV) infection with tenofovir disoproxil fumarate (TDF) and to determine the risk factors involved.

METHODS

Retrospective cohort observational study of adults with chronic hepatitis B. Exclusion: hepatitis C virus-HBV coinfection, diabetes, baseline GFR less than 60 ml/min. Measurements of serum and urinary creatinine and phosphate; urinary albumin, retinol-binding protein (RBP) and neutrophil gelatinase-associated lipocalin (NGAL) were performed. Univariate and multivariate analyses tracked factors associated with worsening GFR.

RESULTS

A total of 120 individuals were included: 35% NAÏVE (G1); 49.2% HBV using TDF (G2); 15.8% HBV-HIV using TDF (G3); 63.3% men; 60.8% white; 30% hypertensive. Average age was 50.5 years (SD ± 12.9 years). Reactive HBeAg predominated in G3 ( P  < 0.001) and cirrhosis in G2 ( P  < 0.036). NGAL was elevated in 5.3% of cases (G1 = 3.2%; G2 = 8.7%; G3 = 0%; P  = 0.582), RBP in 6.7% (G1, G3 = 0%; G2 = 13.6%; P  = 0.012), urinary phosphate/creatinine ratio in 16.2% (G1 = 15.2%; G2 = 14.5%; G3 = 23.5%; P  = 0.842) and urinary albumin/creatinine ratio in 12.9% (G1 = 12.2%; G2 = 10.7%; G3 = 21.1%; P  = 0.494). Worsening of renal function occurred in 22.5% of the population (G1 = 11.9%; G2 = 28.8%; G3 = 26.3%; P  = 0.122), independently associated only with systemic arterial hypertension [adjusted odds ratio (AOR) = 4.14; P  = 0.008], but not to TDF (AOR = 2.66; P  = 0.110) or male sex (AOR = 2.39; P  = 0.135). However, the concomitance of these variables generated a high estimated risk for this outcome (51%).

CONCLUSIONS

Renal tubular dysfunction was uncommon according to NGAL, RBP or urinary phosphate/creatinine ratio. TDF was not an independent factor for worsening renal function, significantly associated only with systemic arterial hypertension. However, in hypertensive men, the use of TDF should be monitored.

Letter: Impact of antiviral treatment on renal function in patients with chronic hepatitis B

This article is linked to Hong et al papers. To view these articles, visit https://doi.org/10.1111/apt.17819 and https://doi.org/10.1111/apt.17937

Effect of pegylated interferon-α2b add-on therapy on renal function in chronic hepatitis B patients: A real-world experience

Background and aim

Controversy remains as to pegylated interferon-α (PEG-IFNα) antiviral therapy to renal function in chronic hepatitis B (CHB) patients. The aim of this study was to evaluate the influence of PEG-IFNα2b (Y shape, 40 kD) add-on treatment for renal function in CHB patients who received entecavir therapy.

Methods

This was a retrospective observational study to investigate factors related to renal function in 114 CHB patients who received PEG-IFNα2b add-on therapy to entecavir for 48 weeks. Changes of blood urea nitrogen (BUN), serum creatinine (sCr), and estimated glomerular filtration rate (eGFR), which was calculated with both Chronic Kidney Disease Epidemiology Collaboration and Modification of Diet in Renal Disease (MDRD) formulas, were analyzed by one-way analysis of variance. A linear mixed effects model for repeated measures was used to assess the correlation between baseline information and eGFR changes at 24 and 48 weeks of therapy. The model considered the baseline age, gender, body weight, viral load, hepatitis B surface antigen, BUN, sCr, and treatment strategy as fixed effects and incorporated random effects for individual subjects.

Results

BUN and sCr was decreased, while eGFR was increased at 12 weeks of therapy. Only eGFR maintained at 24 and 48 weeks of therapy. Patients with female gender, age ≥ 40 years, and baseline HBsAg level &lt; 250 IU/mL showed significant improvement of renal function with PEG-IFNα2b add-on therapy. The linear mixed effects model revealed that female gender, baseline sCr, and PEG-IFNα2b add-on were significant positive predictors for eGFR elevation at 24 and 48 weeks of therapy.

Conclusion

In real-world experience, PEG-IFNα2b add-on therapy might be associated with increased eGFR in CHB patients.

Comparison of renal safety and bone mineral density of tenofovir and entecavir in patients with chronic hepatitis B: A Systematic Review and Meta-analysis

OBJECTIVE

Tenofovir disoproxil fumarate (TDF) and entecavir (ETV) are recommended as first-line treatments for chronic hepatitis B (CHB). However, the safety of these two drugs remains controversial. This study aims to evaluate and compare renal function and bone mineral density in CHB patients who took TDF or ETV.

METHODS

The electronic databases of the Cochrane Library, PubMed, and Embase were searched. The key words were: "CHB," "tenofovir," and "entecavir". Heterogeneity and subgroups were analyzed.

RESULTS

16 studies met the inclusion criteria. There was no significant difference in serum creatinine levels between the TDF and the ETV group. There was a significant standardized mean difference in serum estimated glomerular filtration rate (eGFR) between months (12 months: SMD [95%CI] = -0.07 [-0.12, -0.01]; 18-24 months: SMD [95%CI]=-0.11[-0.17],-0.05]), but no significant difference emerged in the long-term drug use for over 24 months. There was no significant difference in the incidence of osteopenia/osteoporosis (I²=41%, RR [95%CI]=1.29[0.93,1.77], p=0.13>0.05).

CONCLUSIONS

Compared with the ETV group, a greater reduction in eGFR and serum phosphorus levels was observed in the TDF group. There was no significant difference in the incidence of osteopenia/osteoporosis between the two groups.

Long-term renal safety between patients with chronic hepatitis B receiving tenofovir vs. entecavir therapy: A multicenter study

Renal safety is a critical issue in chronic hepatitis B (CHB) patients receiving long-term entecavir (ETV) or tenofovir disofuroxil fumarate (TDF) therapy. We investigated their effects on estimated glomerular filtration rate (eGFR). Treatment-naive CHB patients receiving ETV or TDF for ≥1 year were recruited. The eGFR was assessed using the Chronic Kidney Disease Epidemiology Collaboration equation. We calculated average annual percent change (AAPC) in eGFR using Joinpoint regression. At the beginning of the observation, the ETV group had more unfavorable conditions than the TDF group: lower eGFR and higher FIB-4 and APRI than the TDF group (all p < .001). After 6 years of antiviral therapy, the mean eGFR in the ETV group (n = 1793) was maintained (96.0 at first year to 95.6 ml/min/1.73 m² at sixth year; AAPC -0.09%; p = .322), whereas that in the TDF group (n = 1240) significantly decreased annually (101.9 at first year to 96.9 ml/min/1.73 m² at sixth year; AAPC -0.88%; p < .001). Notably, in the TDF group, even patients without diabetes (AAPC -0.80%; p = 0.001) or hypertension (AAPC -0.87%; p = .001) experienced significant decrease in eGFR. Expectably, accompanying diabetes (AAPC -1.59%; p = .011) or hypertension (AAPC -1.00%; p = .002) tended to accelerate eGFR decrease. TDF treatment (odds ratio 1.66, p < .001), along with eGFR<60 ml/min/1.73 m² , serum albumin<3.5 mg/dl, and hypertension, were independently associated with ongoing renal dysfunction, defined as a negative slope of the mean eGFR change. In conclusion, compared with ETV, long-term TDF treatment induced slow, but progressive renal dysfunction. Although the annual eGFR change by TDF was small, careful monitoring is necessary, especially in patients requiring life-long therapy.

Tenofovir does not induce renal dysfunction compared to entecavir in post-liver-transplant hepatitis B virus patients

Purpose

Tenofovir disoproxil fumarate is accepted as an effective and tolerable drug for treatment of HBV, similar to entecavir. However, there are some concerns about the nephrotoxicity of tenofovir. The aim of this study is to compare the renal-function change of liver recipients who received tenofovir or entecavir for HBV.

Methods

Among 468 patients with HBV who underwent liver transplantation at Samsung Medical Center between January 2008 and December 2015, the patients treated with tenofovir (n = 39) or entecavir (n = 429) were reviewed retrospectively. Baseline characteristics and renal-function change after 1 month, 1 year, and 2 years were compared. Propensity-score matching was performed for 37 patients using tenofovir and 132 patients using entecavir. We also analyzed risk factors of renal dysfunction.

Results

Age, preoperative creatinine, estimated glomerular filtration rate (e-GFR), and hepatic encephalopathy score showed statistical difference between the tenofovir and entecavir groups. The proportion of patients with ‘decreased renal function (e-GFR < 60 mL/min/1.73 m²)’ was higher in the tenofovir group than in the entecavir group (33.3% vs. 12.4% at postoperative one year, P < 0.005). After propensity-score matching, there was no statistical difference in preoperative characteristics. Postoperative 1-, 2-, and 3-year e-GFR and creatinine showed no statistical difference in either group. On multivariate analysis, only preoperative high e-GFR showed a protective effect on renal-function change (odds ratio, 0.97; P < 0.001), and there was no aggravating factor.

Conclusion

Tenofovir disoproxil fumarate does not induce renal dysfunction in liver-transplanted patients with HBV more than does entecavir.

Association between serum Cystatin C and renal injury in patients with chronic hepatitis B

To explore the association between serum cystatin C (Cys-C) and renal damage in patients with chronic hepatitis B.We retrospectively analyzed the clinical data of 425 patients with chronic hepatitis B virus (HBV) infection. Liver stiffness measured by FibroScan was used to diagnosis liver fibrosis. Cys-C levels were detected via latex-enhanced immunoturbidimetric assay.A total of 425 patients were enrolled. Among them, 217 were patients with CHB with an eGFR > 90 mL/min/1.73 m and 208 with an eGFR ≤90 mL/min/1.73 m. Cys-C levels significantly differed in patients with eGFR > 90 mL/min/1.73 m compared with patients with eGFR ≤90 mL/min/1.73 m (0.81 ± 0.05 vs 1.05 ± 0.06 mg/L, P < .001). Moreover, the Cys-C levels were 0.82 ± 0.04 mg/L in patients without liver fibrosis, 0.98 ± 0.05 mg/L in patients with mild liver fibrosis, 1.05 ± 0.08 mg/L in patients with advanced liver fibrosis, and 1.12 ± 0.07 mg/L in patients with liver cirrhosis (P < .001). Multivariate analyses were conducted to explore the independent factors associated with a decreased eGFR. Multivariate analysis suggested that T2DM (P = .032), liver fibrosis (P = .013), and Cys-C level (P = .035) were the independent factors associated with the decreased eGFR in patients with CHB. While age (P = .020) and Cys-C level (P = .001) were the independent factors associated with the decreased eGFR in patients with CHB-related fibrosis.The fibrosis group had significantly higher Cys-C levels than those without fibrosis. Routine monitoring of Cys-C levels is of positive significance in preventing the development of renal impairment of CHB patients.

An observational study on long-term renal outcome in patients with chronic hepatitis B treated with tenofovir disoproxil fumarate

In patients with chronic hepatitis B (CHB), long-term effects of tenofovir disoproxil fumarate (TDF) on renal function have been controversial. This study aimed to analyse the real-world long-term effects of TDF on renal function in Korean patients with CHB. We analysed a cohort of 640 treatment-naïve patients with CHB who were treated with TDF between May 2012 and December 2015 at Severance Hospital, Seoul, Republic of Korea. The mean age was 48.3 years old, and 59.5% were male. The proportions of hypertension and diabetes mellitus (DM) were 11.6% and 14.2%, respectively, and that of liver cirrhosis was 20.8%. During the 5-year follow-up, using a linear mixed model, serum creatinine increased from 0.77 ± 0.01 mg/dL to 0.85 ± 0.02 mg/dL (P < .001), and eGFR decreased from 102.6 ± 0.6 mL/min/1.73 m² to 93.4 ± 1.4 mL/min/1.73 m² (P < .001). In subgroup analysis, eGFR was statistically more decreased in patients with age > 60 than ≦60 years old (P = .027), and in patients with diuretic use than without diuretic use (P = .008). In multivariate analysis, the independent risk factors for eGFR decrease > 20% were baseline eGFR < 60mL/min/1.73 m² (P = .034) and the use of diuretics (P < .001). CHB patients on TDF experienced greater reduction in renal function with age > 60 and with diuretic use compared to those without these characteristics. Baseline eGFR < 60 mL/min/1.73 m² and use of diuretics were independent risk factors of eGFR decline of more than 20% on TDF therapy.

Optimal management of chronic hepatitis B patients receiving nucleos(t)ide analogues

Management of chronic hepatitis B (CHB) is still considered a challenge in clinical practice. Patients must be carefully evaluated before starting therapy. This includes virology and laboratory assessments, an estimation of fibrosis by invasive and/or noninvasive methods, and an estimation of the risk of hepatocellular carcinoma (HCC). Nucleos(t)ide analogues (NAs) with a high barrier to resistance (tenofovir disoproxil fumarate [TDF], entecavir [ETV] and tenofovir alafenamide [TAF]) are the most frequently used treatments because of their good long-term efficacy and tolerability. None of these options has been shown to be more effective than the other, but certain factors should be considered when selecting the best therapy for specific populations. Most patients achieve a virological and biochemical response to these agents, with a low rate of emerging resistance during long-term treatment. However, the rate of hepatitis B surface antigen (HBsAg) loss is low and in most cases NAs therapy is lifelong. Safety concerns for long-term NA use have become a priority in the management of CHB, in particular, the risk of impaired kidney function and bone marrow density loss described with TDF regimens. The risk of HCC is not completely eliminated by NAs. Thus, patients at higher risk should be identified and provided with appropriate surveillance.

Risk factors associated with hypophosphatemia in chronic Hepatitis B patients treated with tenofovir disoproxil fumarate

Tenofovir disoproxil fumarate (TDF) is thought to cause varying degrees of hypophosphatemia in patients with chronic hepatitis B (CHB). Therefore, we investigated factors that cause hypophosphatemia in patients treated with TDF and methods to increase serum phosphorus concentrations in clinical practice.We completed a retrospective review of patients with CHB treated with TDF initially at Kosin University Gospel Hospital, Busan, Korea from January 2012 to January 2017. Subclinical hypophosphatemia and hypophosphatemia were defined as serum phosphorus below 3.0 mg/dL and 2.5 mg/dL, respectively.We screened 206 patients with CHB treated with TDF, among which 135 were excluded for the following reasons: baseline malignancy (59), limited data (50), co-administered other antivirals (14), hypophosphatemia at baseline (7), and other reasons (5). The final study population comprised 71 patients. Subclinical hypophosphatemia developed in 43 (60.5%) patients. Hypophosphatemia occurred in 18 patients (25.3%). Liver cirrhosis was the most significant predictor of hypophosphatemia (P = .038, OR = 3.440, CI = 1.082-10.937) Patients diagnosed with subclinical hypophosphatemia were encouraged to increase their intake of nuts and dairy products (25 patients) or reduce their alcohol intake (2), dose reduction of TDF (4) or placed under observation (4). Among patients with subclinical hypophosphatemia, serum phosphorus concentrations were elevated (>3.0 mg/dL) in 23 of 36 patients (63.8%). Increased nut and dairy intake increased phosphorus concentrations to more than 3.0 mg/dl in 16 of 25 patients (64.0%).Entecavir or tenofovir alafenamide fumarate (TAF) should be considered rather than TDF in patients with liver cirrhosis because of the risk of hypophosphatemia. Instead of stopping TDF treatment, encouraging increased intake of phosphorus-rich foods could increase serum phosphorus concentrations in clinical practice.

Efficacy and Safety of Besifovir Dipivoxil Maleate Compared With Tenofovir Disoproxil Fumarate in Treatment of Chronic Hepatitis B Virus Infection

BACKGROUND & AIMS

Besifovir dipivoxil maleate (BSV) has activity against hepatitis B virus (HBV). We performed a phase 3 study to compare the antiviral efficacy and safety of BSV vs tenofovir disoproxil fumarate (TDF) in patients with chronic HBV infection in Korea.

METHODS

We conducted a double-blind, non-inferiority trial of 197 patients with chronic HBV infection at 22 sites in South Korea, from November 2013 through February 2016. Patients were randomly assigned to groups given BSV (150 mg, n = 99) or TDF (300 mg, n = 98) for 48 weeks. We evaluated virologic responses to therapy (HBV DNA <69 IU/mL or 400 copies/ml), bone mineral density (BMD), and renal outcomes for safety analysis. The main efficacy endpoint was the proportion of patients with a virologic response at week 48. After 48 weeks, TDF was switched to BSV (150 mg) for an additional 48 weeks.

RESULTS

After 48 weeks of treatment, 80.9% of patients given BSV and 84.9% of patients given TDF met the efficacy endpoint, indicating the non-inferiority of BSV to TDF. At week 96, 87.2% of patients in the BSV-BSV and 85.7% of patients in the TDF-BSV had a virologic response. At week 48, changes in hip and spine BMD differed significantly between the BSV and TDF groups, whereas the estimated glomerular filtration rate in the TDF group was significantly lower than that in the BSV group. However, at 96 weeks, there were no significant differences in BMD and estimated glomerular filtration rate between the BSV-BSV and TDF-BSV groups.

CONCLUSIONS

BSV has antiviral efficacy comparable to that of TDF after 48 weeks of treatment, with durable effects for 96 weeks. BSV has a better safety profile than TDF, in terms of bone and renal outcomes. ClinicalTrials.gov no: NCT01937806.

Comparison of renal safety of tenofovir and entecavir in patients with chronic hepatitis B: Systematic review with meta-analysis

BACKGROUND

Recently, the American Association for the Study of Liver Disease suggested no preference between tenofovir (TDF) and entecavir (ETV) regarding potential long-term risks of renal complications. Over the years, renal safety has become a critical concern in nucleos(t)ide analog-treated patients due to the long-term use of these drugs. However, existing studies do not show significant differences in renal dysfunction between these two drugs. Further, there is a paucity of studies comparing the long-term renal effects of TDF and ETV.

AIM

To investigate the effects of TDF and ETV on renal function, we performed systematic review and meta-analysis.

METHODS

Two investigators independently searched the Cochrane Library, MEDLINE, and Embase databases for randomized controlled trials and nonrandomized studies (NRSs) using the keywords “CHB”, “Tenofovir”, and “Entecavir”, and additional references were obtained from the bibliographies of relevant articles published through December 2017. The quality of each study was assessed using the Newcastle-Ottawa scale and the Grading of Recommendations Assessment, Development and Evaluation criteria. The primary outcome was the change in serum creatinine level in the TDF and ETV groups at baseline, 6 mo, 12 mo and 24 mo.

RESULTS

Nine NRSs comprising 2263 participants met the inclusion criteria. Changes in creatinine levels were higher in the TDF group than in the ETV group at 6 mo [mean difference (MD) = 0.03 mg/dL; 95%CI: 0.02-0.04; I² = 0%], 12 mo (MD = 0.05 mg/dL; 95%CI: 0.02-0.08; I² = 78%), and 24 mo (MD = 0.07 mg/dL; 95%CI: 0.01-0.13; I² = 93%). The change in estimated glomerular filtration rate (eGFR) was significantly higher in the TDF group than in the ETV group at 6 mo [standardized mean difference (SMD), -0.22; 95%Cl: -0.36--0.08; I² = 0%], 12 mo (SMD = -0.24; 95%Cl: -0.43--0.05; I² = 50%), and 24 mo (-0.35; 95%Cl: -0.61- -0.09; I² = 67%).

CONCLUSION

TDF statistically significantly increased serum creatinine levels and decreased the eGFR in 6-24 mo compared to ETV, with moderate to low quality of evidence. However, the differences are negligible.

Efficacy of long-term treatment with tenofovir in Chinese nucleos(t)ide-naïve chronic hepatitis B patients regardless of baseline viral load

The aim of the present study was to analyze the efficacy and safety of tenofovir (TDF) treatment for up to 5 years in nucleos(t)ide-naïve chronic hepatitis B (CHB) patients, particularly those with a high viral load, a in real-life scenario. A total of 144 nucleos(t)ide-naïve CHB patients who received TDF monotherapy for at least 3 months were retrospectively analyzed. The primary endpoint measure was the achievement of virological response (VR; undetectable serum HBV DNA, <100 IU/ml). The secondary endpoints were alanine aminotransferase (ALT) normalization (ALT < upper limit of normal), hepatitis B e antigen (HBeAg) seroconversion and safety. The median follow-up period was 120 weeks (range, 12-264 weeks). In total, 144, 130, 114, 78, 67, 40 and 13 patients were followed up for at least 12, 24, 48, 96, 144, 192 and 240 weeks, respectively. An incremental trend was observed in the rate of VR: 73.1, 91.3, 98.1, 100, 100 and 100% of the patients exhibited VR at 24, 48, 96, 144, 192 and 240 weeks, respectively. Furthermore, 29 patients with hepatitis B virus (HBV) DNA ≥8 log₁₀ IU/ml at baseline achieved VR during the follow-up period. The proportions of patients achieving normal ALT levels were 72.1, 78.6, 91.2, 95, 96 and 100%, at 24, 48, 96, 144, 192 and 240 weeks, respectively. The rate of HBeAg loss reached 35.6% at week 240. Among the 130 patients, HBV DNA was detectable [partial VR (PVR)] in 35 patients at 24 weeks of follow-up, and 30 of those 35 patients (85.7%) required >24 weeks of further TDF therapy to achieve VR. No serious adverse events were reported. In conclusion, long-term TDF treatment of nucleos(t)ide-naïve chronic hepatitis B patients, regardless of high viral load at baseline, was effective and safe in a real-life scenario. Adjustment of TDF monotherapy may be unnecessary in nucleos(t)ide-naïve patients with PVR at 24 weeks.

Changes in Renal Function in Patients With Chronic HBV Infection Treated With Tenofovir Disoproxil Fumarate vs Entecavir

BACKGROUND & AIMS

It is unclear whether drugs used to treat chronic hepatitis B virus (HBV) infection cause significant renal impairment. We compare adjusted mean estimated glomerular filtration rates (eGFR; mL/min/1.73 m²) of patients with chronic HBV infection treated with tenofovir disoproxil fumarate (TDF) vs patients treated with entecavir.

METHODS

We performed a retrospective study of patients with chronic HBV infections treated with TDF (n = 239) or entecavir (n = 171), from 2000 through 2016, followed for a mean time of 43-46 months. Levels of serum creatinine were measured ≥12 months while patients received treatment. Patients did not have prior exposure to adefovir or HCV, HDV, or HIV co-infection. We performed propensity score matching (PSM) for age, sex, presence of hypertension, diabetes mellitus, baseline eGFR, cirrhosis, and follow-up duration. We performed multivariate generalized linear modeling, adjusting for cirrhosis, diabetes, and hypertension, to estimate adjusted mean eGFR for matched and unmatched cohorts. Cox regression was used to identify predictors of renal impairment.

RESULTS

eGFRs were ≥60, after PSM, in 116 patients given entecavir and in 116 patients given TDF; eGFRs were <60 in 32 patients given entecavir and 26 patients given TDF. Multivariate generalized linear modeling of the unmatched overall and <60 eGFR cohorts revealed significantly lower adjusted mean eGFRs in patients given TDF (all P < .001). However, in the eGFR ≥60 PSM cohort, the adjusted mean eGFR was similar between patients receiving either treatment. In Cox regression analysis, TDF was not associated with mild or moderate renal impairment compared with entecavir.

CONCLUSION

In a retrospective study of patients with chronic HBV infections treated with TDF vs entecavir, we found that TDF was not associated with higher risk of worsening renal function during short- or intermediate-term follow-up periods, among patients without significant renal impairment. Additional studies, with longer follow-up periods, are needed because treatment for chronic HBV infection is generally long term or life-long. For patients with baseline renal impairment, significant renal decline was among patients given TDF compared to patients given entecavir.

Hepatitis B and renal function: A matched study comparing non-hepatitis B, untreated, treated and cirrhotic hepatitis patients

BACKGROUND & AIM

Renal impairment is associated with chronic hepatitis B (CHB). To overcome prior study design differences, we used propensity score matching to balance the non-CHB and CHB cohorts and generalized linear modelling (GLM, models using probit and logit linking functions for complex models) to evaluate the effect of CHB, treatment and cirrhosis on renal function.

METHODS

A retrospective cohort (1996-2017) from one U.S. university medical centre. Included patients had ≥12 months of serial creatinine laboratories and a baseline estimated glomerular filtration rate (eGFR, by the Modification of Diet in Renal Disease Study equation) ≥60 mL/min/1.73 m² . Propensity score matching was performed using age, sex, ethnicity, diabetes, hypertension and baseline eGFR. GLM was performed to generate adjusted mean eGFR over time.

RESULTS

Adjusted mean eGFR was significantly higher for non-CHB vs. untreated CHB patients (eGFR 87.4 vs. 85.6, P= 0.004, n = 580, median follow-up = 82 months). A significant difference in adjusted mean eGFR between untreated vs. entecavir (ETV)-treated CHB patients (eGFR 85.1 vs. 83.5, P= 0.02, n = 340, median follow-up = 70 months) was found among non-cirrhotic CHB. Among treated CHB, there was no difference in adjusted mean eGFR between non-cirrhotic vs. cirrhotic patients (eGFR 77.0 vs. 76.5; P= 0.66, n = 112, median follow-up = 58 months).

CONCLUSION

After PSM and GLM, the significant predictors for worsening renal function were age, hypertension and diabetes mellitus but not CHB, ETV or cirrhosis. However, given small sample size, data regarding the use of ETV in patients with cirrhosis should be interpreted with caution and requires additional investigation.

Tenofovir alafenamide as compared to tenofovir disoproxil fumarate in the management of chronic hepatitis B with recent trends in patient demographics

Tenofovir alafenamide (TAF) has recently been approved for chronic hepatitis B (CHB). It is more stable than tenofovir disoproxil fumarate (TDF) in the plasma and can provide similar efficacy with lower circulating concentration in patients with hepatitis B virus (HBV) infection. Areas covered: This synopsis will review the current anti-HBV standard practice and the changing epidemiology of CHB, specifically the controversies surrounding the renal and bone safety associated with TDF use in the context of an aging CHB population. We will review data from phase 3 registration trials, which demonstrated TAF was not inferior to TDF in antiviral efficacy for both HBeAg-positive and HBeAg-negative patients, while associated with less reduction in the estimated glomerular filtration rate and bone mineral density. Expert commentary: Current data supports the use of TAF as one of the first-line antiviral agents for general CHB patients without hepatic decompensation. However, more real-world data with long-term observation are needed to better define the role of TAF among other oral regimens. Additional studies are also needed to evaluate the efficacy and safety of TAF in special populations such as those with impaired hepatic function, existing impaired renal and/or bone function, and in pregnant women.