Entecavir (ETV), tenofovir disoproxil fumarate (TDF), and tenofovir alafenamide(TAF) are first-line nucleos(t)ide analogs (NUCs) with chronic hepatitis B (CHB). This study aimed to assess the renal safety profile in NUC-experienced CHB patients who received ETV, TDF or TAF therapy.

This retrospective observational cohort study investigated factors related to renal function in 154 patients with NUC-experienced CHB who received ETV, TDF, and TAF therapy for 48 weeks. Changes in UREA, uric acid (UA), creatinine (Cr), and estimated glomerular filtration rate (eGFR) were analyzed using a one-way analysis of variance. A linear mixed-effects model for repeated measures was used to evaluate the correlation between baseline information and eGFR changes 48 weeks following treatment initiation. The model considered sex, baseline age, viral load, aminotransferases, renal function, and treatment group as fixed effects, and incorporated random effects for individual subjects.

There were no significant differences in UA or Cr levels during therapy over time. The eGFR level was elevated in ETV-treated patients (117.5 ± 16.65 mL/min/1.7m2 vs 109.8 ± 15.69 mL/min/1.7m2, P=0.027), whereas it did not change significantly in TDF- (123.6 ± 28.54 mL/min/1.7m2 vs 115.5 ± 20.44 mL/min/1.7m2, P=0.070) and TAF-treated (121.6 ± 23.44 mL/min/1.7m2 vs 113.4 ± 16.90 mL/min/1.7m2, P=0.053) patients. Younger patients (<30 years) and those with higher HBV DNA (> 7 log10IU/mL) and lower alanine aminotransferase levels (<5 × upper limit of normal) showed a significant improvement in eGFR elevation during NUCs therapy. The linear mixed-effects model showed that the baseline HBV DNA level was an important positive predictor of eGFR elevation at 48 weeks following treatment initiation (estimate was 1.437 and 2.449, P<0.001).

In real-life experience, ETV, TDF, and TAF therapy may not be associated with eGFR changes in NUC-experienced CHB patients without baseline renal impairment.

This study assessed the long-term efficacy and safety of tenofovir alafenamide (TAF) in real-world settings.

Patients who were candidates for TAF treatment and were followed up at 12-week intervals over 192 weeks were enrolled in this study.

One hundred and forty-four patients (50 treatment-naive and 94 treatment-experienced) were included in this study. The cumulative incidence rates of cirrhosis and hepatocellular carcinoma at 192 weeks were 3.9% and 0.7%, respectively. In treatment- naive patients, the rates of a virological response, HBeAg conversion, and HBsAg loss at 192 weeks were 100%, 33.3%, and 2%, respectively. The treatment-naive patients exhibited higher baseline HBsAg levels than the treatment-experienced patients (4.31 log10IU/mL vs. 3.97 log10IU/mL). A significant decrease in the HBsAg levels from the baseline was observed at 144 and 192 weeks in the treatment-naive patients (p=0.01). The baseline body mass index (BMI) <25 kg/m2 (p=0.02) and HBsAg <3.3 log10IU/mL (p=0.04) were identified as predictive factors for a decrease in HBsAg ≥0.5 log10IU/mL at 48 weeks. The eGFR levels were consistently lower in the treatment-experienced patients throughout the study. Although the treatment-naive patients showed no abnormal increases in urinary URBP, the treatment-experienced patients showed elevated urinary β2MG and NAG levels at the baseline, which decreased over the treatment course. The total cholesterol, triglyceride, and low-density lipoprotein levels were similar in both groups.

Prolonging the TAF treatment duration enhances the virological response rate. The decline in HBsAg levels was more significant in the treatment-naive patients than in the treatment-experienced patients. The baseline BMI <25 kg/m2 and HBsAg <3.3 log10IU/mL were predictive factors for a significant decline in HBsAg at 48 weeks. TAF has high renal safety and no significant impact on lipid levels.

Phase 3 studies in patients with chronic hepatitis B have shown tenofovir alafenamide to have non-inferior efficacy to tenofovir disoproxil fumarate, with improved renal and bone safety. We conducted this study to evaluate the safety and efficacy of switching to tenofovir alafenamide in participants with chronic hepatitis B and renal or hepatic impairment.

This open-label, multicentre, phase 2 study was done in eight countries or territories at 30 sites. We recruited adults (≥18 years) with chronic hepatitis B who were virally suppressed on nucleoside or nucleotide analogues and had renal impairment (part A: moderate or severe in cohort 1 [estimated glomerular filtration rate by the Cockcroft-Gault formula (eGFRCG) 15-59 mL/min] or end-stage renal disease [eGFRCG <15 mL/min] on haemodialysis in cohort 2) or hepatic impairment including decompensation (part B: Child-Turcotte-Pugh score 7-12). Participants switched to 25 mg of tenofovir alafenamide given orally once daily for 96 weeks. The primary endpoint was the proportion of participants with viral suppression (HBV DNA <20 IU/mL) at week 24 by missing-equals-failure analysis. Efficacy (full analysis set) and safety (safety analysis set) analyses included all enrolled participants who received at least one dose of the study drug. Week 96 safety was assessed, including renal and bone parameters. This trial is registered at ClinicalTrials.gov, NCT03180619, and is completed.

124 participants (93 in part A [78 in cohort 1 and 15 in cohort 2] and 31 in part B) were enrolled between Aug 11, 2017, and Oct 17, 2018, and included in the full and safety analysis sets. 106 (85%) participants completed the study. There were 69 (74%) men and 24 (26%) women in part A and 21 (68%) men and ten (32%) women in part B. At week 24, 91 (97·8%, 95% CI 92·4 to 99·7) of 93 individuals in part A (76 [97·4%, 91·0 to 99·7] of 78 in cohort 1 and 15 [100·0%, 78·2 to 100·0] of 15 in cohort 2) and 31 (100·0%, 88·8 to 100·0) in part B had HBV DNA of less than 20 IU/mL. By week 96, the most common adverse event was upper respiratory tract infection, which occurred in 14 (15%) participants in part A and in six (19%) participants in part B. Serious adverse events occurred in 20 (22%) part A participants and in ten (32%) part B participants; none were related to treatment. No treatment-related deaths occurred. At week 96, median change in estimated glomerular filtration rate (Cockcroft-Gault method) was 1·0 mL/min (IQR -2·8 to 4·5) in cohort 1 and -2·4 mL/min (-11·4 to 10·7) in part B. Mean changes in spine and hip bone mineral density were 1·02% (SD 4·44) and 0·20% (3·25) in part A and -0·25% (3·91) and 0·28% (3·25) in part B.

Tenofovir alafenamide might offer continued antiviral efficacy and a favourable safety profile for patients with renal or hepatic impairment and chronic hepatitis B switching from tenofovir disoproxil fumarate or other antivirals.

Gilead Sciences.

Tenofovir alafenamide (TAF), a prodrug of tenofovir, delivers high levels of active drug to hepatocytes and is given in a lower dose than tenofovir disoproxil fumarate (TDF). TAF reduces viral replication in patients with chronic hepatitis B (CHB) similar to TDF and has shown a lower risk of the renal and bone toxicities associated with TDF use. This post-marketing surveillance study examined the safety and effectiveness of TAF in treatment-naïve and -experienced CHB patients who received TAF for 144 weeks at real-world clinical sites in Japan. Safety assessments included the incidence of adverse drug reactions (ADRs), renal and bone events, and changes in selected laboratory parameters. Effectiveness was based on the proportion of patients with HBV DNA levels below the lower limit of quantitation or <29 IU/mL. This analysis included 580 patients; 18.4% of whom were treatment-naïve. The cumulative incidence of ADRs was 0.21 per 100 person-months, and the incidence of serious ADRs was 0.01 (95% CI, 0.00-0.04) per 100 person-months. There were no ADRs of declines in estimated glomerular filtration rates, renal failure or proximal tubulopathy. The most common ADR was hypophosphataemia in seven (1.2%) patients. Two (0.4%) patients each had decreased blood phosphorus, bone mineral density decreased, dizziness and alopecia. Overall, the proportion of virologically suppressed patients increased from 68.8% at baseline to 97.5% at Week 144. These results confirm the real-world safety and effectiveness of TAF in Japanese patients with CHB and are consistent with the findings of other evaluations of the safety and efficacy of TAF in CHB.

Tenofovir (TDF) and entecavir (ETV) are first-line treatments for patients with chronic hepatitis B virus (HBV) infection. However, the effect of TDF versus ETV on the prognosis of HBV-related hepatocellular carcinoma (HCC) has not been fully clarified yet.

PubMed, Embase and Web of science were searched up to March, 2021. Meta-analyses were performed for overall survival (OS), disease-free survival (DFS) and recurrence-free survival (RFS) to assess the effect of TDF versus ETV on the prognosis of HBV-related HCC.

A total of 10 studies comprising 4706 Asian patients were included. The pooled results revealed that TDF was associated with better OS (adjusted HR=0.50, 95% CI: 0.40-0.62; I²=36.0%, p=0.167) and better RFS/DFS (adjusted HR=0.70, 95% CI: 0.55-0.89, I²=71.9%, p=0.002) than ETV in treatment of HBV-related HCC. Subgroup analysis revealed that OS benefit from TDF was generally consistent, except for patients who underwent non-surgical treatment for HCC. Subgroup analysis also indicated that TDF reduces the risk of late recurrence (HR=0.41, 95% CI: 0.18-0.0.93; I²=63.0%, p=0.067) rather than early recurrence (HR=0.99, 95% CI: 0.64-1.52; I²=61.3%, p=0.076).

Compared with ETV, TDF has the advantage of improving OS and reducing late recurrence of patients with HBV-related HCC patients who underwent resection.

Background and aims: Adherence to guidelines is associated with improved long-term outcomes in patients with chronic hepatitis B (CHB). We aimed to study the degree of adherence and determinants of non-adherence to management guidelines in a low endemic country. Methods: We reviewed the medical records of all CHB patients who visited our outpatient clinic in 2020. Adherence to guidelines was assessed based on predefined criteria based on the EASL guidance, and included the initiation of antiviral therapy when indicated, the optimal choice of antiviral therapy based on comorbidities, an assessment of HAV/HCV/HDV/HIV serostatus, renal function monitoring and enrolment in a HCC surveillance program if indicated. The adherence rates were compared across types of outpatient clinic (dedicated viral hepatitis clinic versus general hepatology clinic). Results: We enrolled 482 patients. Among the 276 patients with an indication for antiviral therapy, 268 (97.1%) received treatment. Among the patients with renal and/or bone disease, 26/29 (89.7%) received the optimal choice of antiviral agent. The assessment of HAV/HCV/HDV/HIV serostatus was performed in 86.1/91.7/94.4/78.4%. Among the 91 patients treated with tenofovir disoproxil, 57 (62.6%) underwent monitoring of renal function. Of the 241 patients with an indication for HCC surveillance, 212 (88.3%) were enrolled in a surveillance program. Clinics dedicated to viral hepatitis had superior adherence rates compared to general hepatology clinics (complete adherence rates 63.6% versus 37.2%, p < 0.001). Conclusions: Follow-up at a dedicated viral hepatitis clinic was associated with superior adherence to management guidelines.

Tenofovir alafenamide (TAF) is a novel prodrug of tenofovir for the treatment of chronic hepatitis B (CHB) infection. We aimed to evaluate the impact of switching to TAF on alanine aminotransferase (ALT) normalization and renal safety. We also described the indications of switching to TAF. Consecutive adult CHB patients switched from tenofovir disoproxil fumarate (TDF) dominant therapy to TAF for more than 12 months were identified retrospectively. A subgroup of patients newly switched to TAF was prospectively invited to perform transient elastography examination and dual-energy X-ray absorptiometry. The time of switching to TAF was defined as baseline. Among 393 patients in the retrospective cohort, the median ALT at month 12 was significantly lower (21.0 [16.0-29.9] U/L vs. 25.0 [19.0-34.0] U/L; p < 0.001) and ALT normalization rate was higher (89.9% vs. 83.7%; p = 0.037) than those at baseline. Estimated glomerular filtration rate decreased from 12 months before baseline and then increased from baseline to month 12 significantly (69.7 ± 22.0 ml/min/1.73 m2 vs. 68.5 ± 21.5 ml/min/1.73 m2 vs. 69.2 ± 21.5 ml/min/1.73 m2 , p = 0.002 (-12 m vs. baseline), p = 0.004 (baseline vs. 12 m)). In the prospective cohort, 103 patients switched to TAF because of age > 60 years (63.1%), bone diseases (54.4%), and renal alteration (42.7%). TAF is associated with ALT improvement and better renal safety than TDF dominant therapy in CHB patients. Most CHB patients switched to TAF because of advanced age, followed by bone disease and renal alteration.

Tenofovir disoproxil fumarate (TDF) and entecavir (ETV) have been recommended after liver transplantation to prevent recurrence of hepatitis B virus infection. Despite its proven efficacy, the renal safety of TDF has not been established in liver transplant recipients. We aimed to compare the effects of TDF and ETV on renal function in liver transplant recipients and to evaluate risk factors for renal dysfunction after liver transplantation.

This is a retrospective, observational multicenter study of data from the Korean Organ Transplantation Registry. We included adults who underwent liver transplantation for hepatitis B virus-related complications from April 2014 to December 2017 and received TDF or ETV post-transplantation. Renal dysfunction was defined as an estimated glomerular filtration rate decline by at least 20% from baseline (1 month post-transplantation). Median duration of follow-up was 29 months (interquartile range 19-42).

A total of 804 liver transplant patients were included. The cumulative probability of renal dysfunction was significantly higher in the TDF group than in the ETV group. Multivariable analysis confirmed that TDF was independently associated with an increased risk of renal dysfunction (hazard ratio = 1.47, 95% confidence interval 1.12-1.92; p = 0.005). Independent risk factors for renal dysfunction included older age, worse baseline renal function, and low body mass index. Overall survival rate was significantly lower in patients with renal dysfunction than in those without.

In this nationwide study, the use of TDF was associated with an increased risk of renal dysfunction, when compared with ETV.

Of the antiviral agents currently available to patients with chronic hepatitis B (CHB), entecavir (ETV) and tenofovir disoproxil fumarate (TDF) are 2 of 3 first-line agents.1-3 Given the well-known renal and bone toxicity associated with TDF,4 major international hepatitis B virus treatment guidelines recommend ETV over TDF in patients with predisposing factors to kidney function decline.1-3 However, as evidenced by recent studies, nephrotoxicity of antiviral agents is still an issue under debate.5-7 Therefore, we investigated the differences in the risk of kidney function decline in patients with treatment-naive CHB who were treated with ETV or TDF.

Nucleoside analogues are the drugs most commonly used in the treatment of chronic hepatitis B. They act by inhibiting viral replication and have minimal impact on HBsAg loss. Nucleoside analogues are indicated in patients with chronic hepatitis, cirrhosis, decompensated cirrhosis, hepatocellular carcinoma, and in those with extrahepatic manifestations. Real-world experience has been ongoing for more than 10 years, and the efficacy and safety results obtained are similar to those reported in clinical trials. Prolonged use is needed to maintain suppression of viral replication, prevent the development of liver cirrhosis and decompensated cirrhosis, and to decrease the risk of hepatocellular carcinoma.