Switching from entecavir to tenofovir alafenamide versus maintaining entecavir for chronic hepatitis B

Dynamic evaluation of liver fibrosis to assess hepatocellular carcinoma risk in patients with chronic hepatitis B receiving nucleoside analogs treatment

Despite good hepatitis B virus (HBV) inhibition by nucleoside analogs (NAs), cases of hepatocellular carcinoma (HCC) still occur. This study proposed a non-invasive predictive model to assess HCC risk in patients with chronic hepatitis B (CHB) receiving NAs treatment. Data were obtained from a hospital-based retrospective cohort registered on the Platform of Medical Data Science Academy of Chongqing Medical University, from 2013 to 2019. A total of 501 patients under NAs treatment had their FIB-4 index updated semiannually by recalculation based on laboratory values. Patients were divided into three groups based on FIB-4 index values: < 1.45, 1.45-3.25, and ≥ 3.25. Subsequently, HCC incidence was reassessed every six months using Kaplan-Meier curves based on the updated FIB-4 index. The median follow-up time of CHB patients after receiving NAs treatment was 2.5 years. HCC incidences with FIB-4 index < 1.45, 1.45-3.25, and ≥ 3.25 were 1.18%, 1.32%, and 9.09%, respectively. Dynamic assessment showed that the percentage of patients with FIB-4 index < 1.45 significantly increased semiannually (P < 0.001), and of patients with FIB-4 index ≥ 3.25 significantly decreased (P < 0.001). HCC incidence was the highest among patients with FIB-4 index ≥ 3.25. The FIB-4 index effectively predicted HCC incidence, and its dynamic assessment could be used for regular surveillance to implement early intervention and reduce HCC risk.

Effects of entecavir and tenofovir alafenamide fumarate treatment on renal function in Japanese elderly patients with chronic hepatitis B

AIM

Entecavir (ETV) and tenofovir alafenamide fumarate (TAF) are considered safe nucleoside/nucleotide analogs (NA) for the kidney. This study aimed to investigate the long-term effects of ETV or TAF on renal function in elderly patients with chronic hepatitis B (CHB) in Japan.

METHODS

The study included 246 CHB patients treated with ETV (184 patients) or TAF (62 patients) for at least 2 years. These patients were divided into two groups: those <65 years of age (130 patients) and those ≥65 years of age (116 patients). The effects of the NAs on renal functions were examined by comparing the estimated glomerular filtration rates (eGFR) from baseline to 2 years between the two groups.

RESULTS

The change in eGFR from baseline to 1 or 2 years after treatment was significantly decreased in both groups. However, the amount of change at 1 and 2 years was significantly greater in the group aged ≥65 years than in the group aged <65 years. The amount of change in eGFR from baseline to 1 and 2 years after treatment was significantly greater in the group aged ≥65 years than in the group aged <65 years, regardless of the type of NA, the prior treatment history, cirrhosis/chronic hepatitis, hypertension, dyslipidemia, and diabetes. Additionally, logistic regression analysis showed that age ≥65 years was independently associated with a decreased eGFR after 2 years of NA treatment.

CONCLUSIONS

Long-term administration of NA to CHB patients over 65 years of age should be carefully monitored for renal impairment.

Increased spine bone density in patients with chronic hepatitis B switched to tenofovir alafenamide: A prospective, multinational study

BACKGROUND

Data on patients switched to tenofovir alafenamide (TAF) from nucleos(t)ide analogues (NUCs) other than tenofovir disoproxil fumarate are limited.

AIMS

To assess the treatment and renal/bone safety outcomes following the switch to TAF.

METHODS

We prospectively enrolled adult patients with chronic hepatitis B (CHB) who switched from any NUC to TAF at 14 centres in Japan, Korea, Taiwan and the U.S. Study outcomes were viral suppression (VR; HBV DNA < 20 IU/mL), biochemical response (BR; alanine aminotransferase normalisation), and changes in estimated glomerular filtration rate (eGFR) and T-scores (L-spine) by bone absorptiometry by 24 months after switch to TAF.

RESULTS

We enrolled 270 eligible patients. Mean age was 58.1; 58.2% were male; 12.2% had cirrhosis and 73.3% previously received entecavir monotherapy. VR rate increased significantly from 95.2% to 98.8% by 24 months after the switch to TAF (p = 0.014). Between the switch and 24 months later, the mean spine T-score improved significantly from -1.43 ± 1.36 to -1.17 ± 1.38 (p < 0.0001), while there was no significant change in mean eGFR (88.4 ± 16.9-89.5 ± 16.3 mL/min/1.73 m2 , p = 0.13). On multivariable analysis adjusted for age, sex, baseline spine T-score and prior TDF or adefovir dipivoxil use, male sex was significantly associated with lower risk of worsening spine T-score (odds ratio: 0.29, p = 0.020), while age was significantly associated with a higher risk of worsening chronic kidney disease stage (OR: 1.07, p = 0.019).

CONCLUSIONS

At 24 months after the switch to TAF, VR rates and spine bone density improved significantly while renal function remained stable.

Switching from entecavir to tenofovir alafenamide for maintaining complete virological response in chronic hepatitis B

Background and Aim

Hepatocellular carcinoma development can be decreased by achieving and maintaining complete virological response (CVR) in chronic hepatitis B. However, it is unclear whether switching from entecavir (ETV) to tenofovir alafenamide (TAF) could achieve and maintain CVR in patients with low-level viremia (LLV; HBV DNA ≤ 3.3 log IU/mL) or occasional detectable HBV DNA during ETV treatment. Therefore, we aimed to examine whether the switching from ETV to TAF is effective in achieving CVR in patients with LLV or occasional detectable HBV DNA.

Methods

This study comprised 45 patients who switched from ETV to TAF. All patients received ETV and TAF for >2 years, and the HBV DNA levels were measured every 3 months. Maintaining undetectable HBV DNA during 2-year period is defined as CVR. The primary endpoint is the CVR rate during ETV and TAF treatment.

Results

The CVR rate for each of the 2 years of ETV and TAF therapy was 33.3% (15/45) and 68.9% (31/45, P < 0.01), respectively, and the CVR rate increased by switching from ETV to TAF. In patients with occasional detectable HBV DNA during ETV treatment (22 patients), 15 achieved CVR and 7 maintained occasional detectable HBV DNA. In patients with LLV during ETV treatment (eight patients), three achieved CVR and five had occasional detectable HBV DNA.

Conclusion

Switching from ETV to TAF increases the CVR rate in patients with LLV or occasional detectable HBV DNA and could be an alternative treatment option.

Alanine aminotransferase levels as therapeutic targets after nucleotide/nucleoside analog therapy in patient with chronic hepatitis B

AIM

Alanine aminotransferase (ALT) is a criterion for the introduction of nucleotide/nucleoside analog (NA), and ALT levels are decreased by NA treatment. However, the association between post-treatment ALT levels and hepatocellular carcinoma (HCC) risk remains unclear. To fill this gap, we aimed to establish a target value of ALT level during NA treatment.

METHODS

In total, 413 patients with chronic hepatitis B who received entecavir, tenofovir alafenamide, or tenofovir disoproxil fumarate were enrolled. The subsequent development of HCC was examined and a target value of ALT level during NA treatment as a risk marker for HCC was evaluated.

RESULTS

The median follow-up duration was 5.1 years, during which time 27 patients (8.6%) developed HCC. ALT level at the start of treatment was not associated with HCC development (p = 0.08). When stratified by ALT at 1 year after NA initiation, the cumulative 3- and 5-year rates of HCC for patients with ALT ≥21 IU/L were 11.5% and 18.1%, and those with ALT <21 IU/L was 2.3% and 6.5%, respectively. Patients with ALT <21 IU/L had a significantly lower risk of HCC development compared with patients with ALT ≥21 IU/L (p = 0.002). In multivariable analysis adjusting age, sex, and platelet counts, ALT ≥21 IU/L was an independent risk factor of HCC development with hazard ratio of 4.5 (95% confidence interval: 1.01-20.4).

CONCLUSIONS

ALT <21 IU/L at 1 year after NA initiation has a lower risk of HCC and could be used as a target value for NA treatment.

Switching to tenofovir alafenamide versus continued therapy in chronic hepatitis B patients who were treated with entecavir: A prospective, multicenter, randomized controlled study

BACKGROUNDS

Entecavir (ETV) and tenofovir alafenamide fumarate (TAF) have been used widely to treat patients with chronic hepatitis B virus (HBV) infection, but it is still unclear how best to use these drugs. Although some studies compared the efficacies of treatment switch from ETV to TAF, there has been no randomized study.

METHODS

We performed a prospective multicenter randomized controlled study in which subjects were enrolled from April 2018 to June 2019 and observed for 2 years until March 2021 to clarify the efficacy and safety of switching from ETV to TAF.

RESULTS

Thirty-three patients were enrolled and randomized into 2 groups, and a total of 30 patients were evaluated; a TAF-switching group (n = 16) and an ETV-continuing group (n = 14). The mean age of the 30 patients was 61 years old and 18 patients (60%) were male. The serum HBV DNA in all patients were below detection limit. The mean change in hepatitis B surface antigen (HBsAg) levels after 2 years was not significantly different between the TAF and ETV groups (-0.08 vs -0.20 log IU/mL, P = .07). Comparing the group with a HBsAg decline (≤ -0.1 log IU/mL) and a group without a HBsAg decline in an overall analysis, the prior ETV duration was significantly shorter in the HBsAg-declined group (49 vs 92 months, P = .03). Although the eGFR levels tended to decrease in the TAF group compared to ETV (-6.15 vs -2.26 mL/min/1.73 m2, P = .09), no significant differences were observed in patients with baseline eGFR < 60 (-2.49 vs 0.40 mL/min/1.73 m2, P = .25).

CONCLUSION

The efficacy and safety were comparable in the TAF-switching group and the ETV-continuing group. Because the present study was conducted in limited patients, a larger study will be required.

Review article: switching patients with chronic hepatitis B to tenofovir alafenamide-a review of current data

BACKGROUND

The nucleos(t)ide analogues (NAs) entecavir (ETV), tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide (TAF) are preferred treatment options for patients with chronic hepatitis B infection (CHB). However, resistance to ETV has been reported, especially with prior exposure to other NAs, and long-term TDF treatment has been associated with decline in renal function and loss of bone mineral density in some patients. Consequently, TAF may be preferable to ETV, TDF or other NAs in specific circumstances such as in patients with risk of bone or renal complications, elderly patients or those with previous NA experience.

AIM

To provide a summary of the available efficacy and safety data following switch to TAF from other NAs in patients with CHB in clinical studies and real-world settings.

METHODS

Literature searches were performed on PubMed and abstracts from three major international liver congresses between 2019 and 2021. Studies that included efficacy and/or safety data for patients with CHB switching from any NA to TAF were selected.

RESULTS

Thirty-six papers and abstracts were included in this narrative review. Switching from TDF to TAF maintained or improved virological and biochemical responses with improved bone and renal safety. Switching from ETV or other NAs to TAF maintained or improved virological and biochemical responses and varying results for bone and renal safety.

CONCLUSIONS

Switching to TAF appears to maintain or improve virological, biochemical and bone- and renal-related safety outcomes. These data support the concept of switching to TAF in some patients with CHB based on their individual circumstances.

Superiority of tenofovir alafenamide fumarate over entecavir for serum HBsAg level reduction in patients with chronic HBV infection: A 144-week outcome study after switching of the nucleos(t)ide analog

Background

To evaluate the long-term efficacy of switching of the nucleos(t)ide analog used for treatment from entecavir (ETV) to tenofovir alafenamide fumarate (TAF) in patients with chronic HBV infection.

Methods

A total of 103 patients with serum HBsAg levels of ≥100 IU/mL who had received ETV were enrolled. The nucleos(t)ide analog used for the treatment was switched from ETV to TAF, and the changes in serum HBsAg levels during the 144-week period before and after the drug switching were compared in 74 patients who had received ETV at least for 192 weeks.

Results

Significant decreases of serum HBsAg levels were observed during both the ETV and the TAF administration period, although the degree of reduction was greater during the latter period than during the former period (P<0.001). Significant decreases of serum HBsAg levels were seen in both patients with genotype B HBV infection and genotype C HBV infection, irrespective of the serum HBsAg and HBcrAg levels at the time of the drug switching.

Conclusion

Switching of the nucleos(t)ide analog used for treatment from ETV to TAF merits consideration in patients with chronic HBV infection, since the extent of reduction of the serum HBsAg level was greater during the TAF treatment period than during the ETV treatment period.

Comparison of Tenofovir Alafenamide and Entecavir Therapy in Patients with Chronic Hepatitis B Initially Treated with Tenofovir Disoproxil: A Retrospective Observational Survey

Background: In chronic hepatitis B patients with or exposed to the risk of osteoporosis or renal dysfunction, switching from tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide fumarate (TAF) or entecavir (ETV) may be the right choice. Objectives: This study aimed to present real-life data in terms of the efficacy and safety of a TAF/ETV treatment change while receiving TDF. Methods: This retrospective study was conducted on 344 adult patients from 10 centers. The data of patients who had changed to ETV (n = 107) and TAF (n = 237) while receiving TDF were analyzed. The data collected at 0 and 6 months of treatment were analyzed. The virological response was assessed based on undetected hepatitis B virus (HBV) DNA. Serum alanine aminotransferase (ALT) values were used to evaluate the biochemical response. For renal function, serum creatinine and phosphorus, as well as estimated glomerular filtration rate (eGFR), were recorded. Moreover, lumbar spine and hip T-scores along with the serum lipid profile were evaluated. Results: The mean age of patients was 41.14 ± 13.46 years, and 224 (65.1%) of the participants were male. The treatment arms were not significantly different in terms of demographic characteristics, comorbid diseases, infection duration, family history of HBV infection, blood platelet count, serum biomarkers, such as ALT, phosphorus, creatinine, total bilirubin, albumin, lipid profile, and HBV DNA levels at the beginning. No statistically significant difference was found between the proportion of undetectable HBV DNA of the two treatment groups after 6 months (P = 0.221). The ALT normalization in the ETV and TAF groups at the sixth month compared to the baseline levels was not significantly different (P = 0.853, P = 0.330, respectively). There was no statistically significant difference between the two treatment arms regarding changes in eGFR, creatinine, phosphorus, hip, and spine T-scores from baseline to 6 months (P = 0.296, P = 0.78, P = 0.141, P = 0.832, P = 0.947, respectively). In those who switched to TAF or ETV, low-density lipoproteins cholesterol were observed to be significantly higher after 6 months compared to baseline values (P = 0.002, P = 0.049, respectively). The TC increased significantly in the TAF group (P = 0.035). Conclusions: Our study showed that switching to ETV and TAF sustained the viral suppression and biochemical response achieved by TDF therapy. The treatment switch to TAF of ETV can control renal dysfunction and reduce bone mineral density caused by TDF.

Change in tartrate-resistant acid phosphatase isoform 5b levels, a marker of bone metabolism, in patients with chronic hepatitis B treated with tenofovir alafenamide

Hepatitis B virus (HBV) infection is associated with the risk of osteoporosis and bone mineral density (BMD) loss. Tenofovir alafenamide (TAF) is associated with a slightly lower degree of BMD loss compared with tenofovir disoproxil, without loss of the excellent anti-HBV effects. The aim of the present study was to verify the effect of bone metabolism in patients with HBV treated with TAF. A total of 87 patients were treated with TAF. Of these, 32 patients were treatment naïve, and 55 patients were treated with entecavir (ETV) for at least 1 year, after which ETV was switched to TAF. At the start of TAF and after 1 year, BMD in the lumbar and neck of the femur, tartrate-resistant acid phosphatase isoform 5b (TRACP-5b) levels as a marker of bone metabolism and serum inorganic phosphorus (P) were compared to estimate bone metabolism. Serum creatinine (Cr), cystatin C, urine protein and β2 microglobulin levels were evaluated to estimate kidney function. Treatment with TAF for 1 year decreased TRACP-5b levels, particularly in patients with bone disease, except for a minimal significant change (MSC; decrease of 12.4%) in TRACP-5b levels. The change in rate of TRACP-5b levels were positively associated with changes in P, Cr-estimated glomerular filtration rate and TRACP-5b levels at the start of TAF. Logistic regression analysis showed that increased BMD in the lumbar region contributed to the switch from ETV to TAF. TAF induced a decrease in TRACP-5b levels in patients with HBV. Bone disease was a contributing factor for MSC. Since TRACP-5b can be used as a marker of bone metabolism and fractures, TAF may exhibit potential in preventing fractures in patients with HBV.

Body weight changes in treated hepatitis B patients switching to tenofovir alafenamide☆

BACKGROUND/PURPOSE

Switching to a tenofovir alafenamide (TAF)-containing regimen has been reported to be associated with body weight gain in human immunodeficiency virus-infected subjects. We aimed to investigate the body weight change and virological, hepatic, and renal outcomes of TAF switching among chronic hepatitis B (CHB) patients.

METHODS

This retrospective study included 121 CHB patients who were switched to TAF after >12 months of treatment with another nucleot(s)ide analog (NUC). All patients were monitored for 12 months.

RESULTS

The cohort was mostly Asian (96.7%) with a mean age of 55 years, 72% male, 14% cirrhosis, 21% HBeAg positive, and 75% with prior use of tenofovir disoproxil fumarate. At 12 months after TAF switching, their body weight significantly increased from 66.4 ± 11.8 to 67.8 ± 12.3 kg (p < 0.001), and 21.1% of the subjects had a ≥5% weight gain. Patients without diabetes or hypertension were more likely to have a body weight gain. Meanwhile, the complete viral suppression rate increased significantly from 89.3% to 96.2% (p = 0.016). The rate of alanine aminotransferase normalization also increased significantly from 71.1% to 87.6% (p < 0.001) by local criteria and from 58.7% to 70.2% (p = 0.029) by AASLD criteria. The mean eGFR (mL/min/1.73 m²) did not change (88.2 ± 18.8 vs. 87.2 ± 17.5, p = 0.28). However, for the subgroup with GFR <90 at TAF switching, there was a significant improvement in eGFR (72.9 ± 12.0 vs. 75.7 ± 14.2, p = 0.027).

CONCLUSION

In real-world NUC-experienced CHB patients, unexpected body weight gain was observed after TAF switching. The mechanism needs to be investigated in the future.

Comparison of efficacy and safety of entecavir and switching from entecavir to tenofovir alafenamide fumarate in chronic hepatitis B: Long-term effects from a prospective study

AIM

Both entecavir (ETV) and tenofovir alafenamide fumarate (TAF) are widely used to treat chronic hepatitis B (CHB) in Japan. However, it remains unclear whether the efficacy of TAF in decreasing the hepatitis B surface antigen (HBsAg) level, and its safety, are superior to those of ETV. This study aimed to report the long-term effects and safety of 96-week ETV and TAF treatment in patients with CHB.

METHODS

A prospective comparative observational study was undertaken on the following two groups: patients with CHB who received continuous ETV (n = 32) and patients with CHB who were switched from ETV to TAF upon request (n = 48). The HBsAg, urinary β2-microglobulin (β2MG)/creatinine (Cr), urinary N-acetyl-β-D-glucosaminidase (NAG)/Cr, and serum alanine aminotransferase (ALT) levels, estimated glomerular filtration rate (eGFR), and bone mineral density (lumbar spine and femur) at 96 weeks were compared.

RESULTS

The two groups did not significantly differ with respect to mean age, male / female patient ratio, or rate of hepatitis B e antigen-positive status. The mean changes in serum HBsAg level and eGFR at 96 weeks were not significantly different between the two groups. The β2MG/Cr and NAG/Cr levels at 96 weeks were similar between the two groups. Additionally, the bone mineral density of the lumbar spine and femur as well as the serum ALT did not significantly differ.

CONCLUSIONS

When compared with patients who received continuous ETV, those who were introduced to TAF after ETV showed similar effects in terms of the decrease in HBsAg level and safety.

Switching from entecavir to tenofovir alafenamide for chronic hepatitis B patients with low-level viraemia

BACKGROUND AND AIMS

About 20% of patients receiving nucleos(t)ide analogues treatment experienced low-level viraemia (LLV), which is associated with progression of liver fibrosis and high risk of hepatocellular carcinoma. We aimed to evaluate the effectiveness and safety of switching from entecavir (ETV) to tenofovir alafenamide fumarate (TAF) in ETV-treated patients with LLV.

METHODS

In this prospective study, ETV-treated patients with LLV, presented to our hospital from December 2018 to October 2019, were enrolled. Switching to TAF or continuing ETV was given. The primary effectiveness endpoint was complete virological response (CVR) at 24 weeks, and the safety endpoint was the first occurrence of any clinical adverse event during the treatment.

RESULTS

Totally, 211 patients were recruited and propensity score matching (PSM) generated 75 patients in either TAF or ETV group. After PSM, baseline characteristics were balanced in two groups. After 24-week treatment, the CVR and ALT normalization in TAF group were 62.7% and 47.6%, which were higher than 9.3% and 10.5% in ETV group (OR 16.4, 95% CI 6.6-40.0, P < .001) respectively. Subgroup analysis showed that switching to TAF achieved favours CVR regardless of the status of sex, age, CHB family history, HBV DNA, HBeAg and cirrhosis, whereas alcohol consumption and diabetes mellitus might compromise the CVR of switching to TAF. Both therapies were well tolerated and had satisfying renal safety.

CONCLUSIONS

For ETV-treated patients with LLV, switching to TAF is safe enough and superior compared with continuing ETV monotherapy regarding both virological and biochemical benefits.

Outcomes of Sequential Therapy With Tenofovir Alafenamide After Long-term Entecavir

INTRODUCTION

Entecavir (ETV) and tenofovir alafenamide (TAF) are both first-line hepatitis B virus (HBV) therapies, but ETV-to-TAF switch outcome data are limited. We aimed to assess outcomes up to 96 weeks after ETV-to-TAF switch.

METHODS

ETV-treated (≥12 months) chronic hepatitis B patients switched to TAF in routine practice at 15 centers (United States, Korea, Japan, and Taiwan) were included. Primary outcome was complete viral suppression (CVS) rate (HBV DNA <20 IU/mL).

RESULTS

We analyzed 425 eligible patients (mean age 60.7 ± 13.2 years, 60% men, 90.8% Asian, 20.7% with diabetes, 27% with hypertension, 14.8% with cirrhosis, 8.3% with hepatocellular carcinoma, and mean ETV duration before switch 6.16 ± 3.17 years). The mean baseline estimated glomerular filtration rate (eGFR) was 89 ± 19 (chronic kidney disease [CKD] stages: 55.6% stage 1, 35.7% stage 2, and 8.8% stages 3-5). CVS rate increased from 91.90% at switch (from 90.46% 24 weeks before switch) to 95.57% and 97.21% at 48 and 96 weeks after (P = 0.03 and 0.02, respectively). Over the 96 weeks after switch, mean HBV DNA (P < 0.001) but not alanine aminotransferase or CKD stage decreased. Between switch and 96-week follow-up, 11% (26/235) of CKD stage 1 patients migrated to stage 2 and 8% (12/151) of stage 2 patients to stages 3-5, whereas 18% (27/151) from stage 2 to 1, and 19% (7/37) from stages 3-5 to 2. On multivariable generalized estimated equation analysis adjusted for age, sex, hypertension, diabetes, and cirrhosis, baseline eGFR, age (P < 0.001), and CKD stages 2 and 3-5 (vs 1) (both P < 0.001) were associated with lower follow-up eGFR.

DISCUSSION

After an average of 6 years on ETV, CVS increased from 91.9% at TAF switch to 97.2% at 96 weeks later.

Dynamic evaluation of hepatocellular carcinoma prediction models in patients with chronic hepatitis B receiving nucleotide/nucleoside analogue treatment

Carcinogenesis risk scores for chronic hepatitis B have been proposed, but it remains unclear whether these scores during nucleoside/nucleotide analogue (NA) therapy are useful for risk assessment. In this study, we examined changes of these scores and the predictability during NA treatment. 432 patients with no history of hepatocellular carcinoma (HCC) treated with NA were enrolled. PAGE-B, modified PAGE-B (mPAGE-B), and REACH-B scores were calculated at NA administration, 1 and 2 years after administration. The median follow-up duration was 5.1 years, during which 37 patients (8.6%) developed HCC. Cumulative incidence HCC development in patients with high risk of PAGE at NA administration, and 1 and 2 years after NA administration was significantly higher than those with intermediate and low-risk groups (p < .05 for all time points), whereas HCC incidence in patients with high risk of mPAGE-B and REACH-B at 2 years after NA administration were equivalent to those with intermediate and low-risk groups (p = .2 for mPAGE-B, and p = .1 for REACH-B). The area under the receiver operating characteristic (AUROC) for HCC development of PAGE-B at NA administration, and 1 and 2 years after administration were 0.773, 0.803 and 0.737, respectively. The AUROCs of PAGE-B at each point were continuously higher than those of REACH-B (0.646, 0.725, and 0.653, respectively) and mPAGE-B (0.754, 0.734, and 0.678, respectively).PAGE-B score has a high diagnostic accuracy for HCC development at any time point during NA treatment, indicating its potential use as a real-time monitor of HCC development.

Tenofovir Alafenamide Rescues Renal Tubules in Patients with Chronic Hepatitis B

Nucles(t)ide analogs (NAs) are effective for chronic hepatitis B (CHB). NAs suppress hepatic decompensation and hepatocarcinogenesis, leading to a dramatic improvement of the natural course of patients with CHB. However, renal dysfunction is becoming an important issue for the management of CHB. Renal dysfunction develops in patients with the long-term treatment of NAs including adefovir dipivoxil and tenofovir disoproxil fumarate. Recently, several studies have reported that the newly approved tenofovir alafenamide (TAF) has a safe profile for the kidney due to greater plasma stability. In this mini-review, we discuss the effectiveness of switching to TAF for NAs-related renal tubular dysfunction in patients with CHB.

Comparison of the impact of tenofovir alafenamide and entecavir on declines of hepatitis B surface antigen levels

OBJECTIVE

Tenofovir alafenamide is a new prodrug of tenofovir that allows for the treatment of patients with hepatitis B virus (HBV) at a lower dose than with tenofovir disoproxil fumarate, due to the more efficient delivery of tenofovir to hepatocytes. In this study, we compared entecavir and tenofovir alafenamide in terms of their ability to reduce hepatitis B surface antigen (HBsAg) in the same group of patients with HBV infection.

METHODS

During March and June 2018, 129 patients who received entecavir were switched to tenofovir alafenamide. Every 3- 6 months for 1 year before and after switching to tenofovir alafenamide, all patients underwent measurements of HBsAg, hepatitis core-related antigen (HBcrAg), calcium (Ca), inorganic phosphorus, and estimated glomerular filtration rate (eGFR).

RESULTS

The percent decline rate during the entecavir and tenofovir alafenamide phases at 6 months were 2.38% (-3.57 to 0.00) and -3.57% (-7.14 to 0.00), respectively, and those at 12 months were 3.03% (-6.57 to 0.00) and -5.56% (-7.41 to -2.50), respectively. HBsAg levels were reduced significantly more during the tenofovir alafenamide phase than during the entecavir phase (P < 0.0001). There were no significant differences in the percent declines of HBcrAg, Ca, inorganic phosphorus, or eGFR during the entecavir and tenofovir alafenamide phases after 1 year.

CONCLUSION

tenofovir alafenamide significantly decreased HBsAg levels compared to entecavir.

Sequential therapy from entecavir to tenofovir alafenamide versus continuous entecavir monotherapy for patients with chronic hepatitis B

Background and Aim

Although tenofovir alafenamide (TAF), as well as entecavir (ETV), is widely used as first‐line treatment for patients with chronic hepatitis B, there are only a few studies comparing sequential therapy from ETV to TAF and continuous ETV monotherapy in patients with maintained virologic response to ETV.

Methods

In a retrospective multicenter study, we investigated the efficacy and safety of sequential therapy from ETV to TAF (ETV‐TAF group) and compared them with continuous ETV monotherapy (ETV group), using propensity score matching, in chronic hepatitis B patients.

Results

From 442 patients, we analyzed 142 patients from each group comprising 71 patients matched for several data, including age, HBV genotype, hepatitis B envelope antigen, cirrhosis, alanine aminotransferase, platelet count, prior ETV monotherapy period, and hepatitis B surface antigen (HBsAg) change during prior ETV monotherapy. In the ETV‐TAF group, HBsAg levels significantly decreased from baseline to 48 weeks after switching to TAF (−0.02 log IU/mL, P = 0.038). HBcrAg levels also significantly decreased after switching to TAF (−0.1 log IU/mL, P = 0.004). However, there were no significant differences in the reduction of HBsAg and HBcrAg levels between the ETV‐TAF and ETV groups. There was no significant difference in the change of estimated glomerular filtration rate levels from baseline to 48 weeks between the two groups.

Conclusions

The present study indicated that the efficacy, especially of the HBsAg‐reducing action, and safety of sequential therapy from ETV to TAF were similar to those of continuous ETV monotherapy among chronic hepatitis B patients with maintained virologic response to ETV.

Switching to tenofovir disoproxil fumarate in entecavir-treated chronic hepatitis B patients: A pilot randomized controlled study

Although hepatitis B surface antigen (HBsAg) removal is considered the goal of chronic hepatitis B treatment, it can rarely be achieved with nucleos(t)ide analogues (NAs). It has been reported that tenofovir disoproxil fumarate (TDF) is superior in reducing HBsAg compared with entecavir (ETV) in treatment-naïve patients; however, the effect of TDF in patients who have received NAs is still unclear. The aim of the present study was to evaluate the efficacy of switching from ETV to TDF in patients who were already receiving ETV. A pilot randomized controlled study for 2 years in patients who had been treated with ETV for >1 year and did not exhibit drug resistance was performed (Clinical trial registration: UMIN000021948, UMIN-CTR, May 1, 2016). A total of 20 patients were enrolled and 19 patients were randomized into 2 groups, a TDF-switching group (n=12) or an ETV-continuing group (n=7). The mean change in HBsAg levels after 2 years was greater in the TDF group compared with the ETV group, but the difference was not significant (-0.25 vs. -0.06 log IU/ml). In the TDF group, hepatitis B e antigen (HBeAg)-positive patients at baseline showed significantly greater changes in HBsAg (-0.63 vs. -0.03 log IU/ml; P=0.030). In contrast, no difference between HBeAg-positive and HBeAg-negative patients was observed in the ETV group. No significant differences of estimated glomerular filtration rate and inorganic phosphorus changes were observed among the TDF and ETV groups. In conclusion, a significant HBsAg decrease was not achieved after switching from ETV to TDF in the overall analysis, but HBeAg-positive patients showed a larger HBsAg decrease after switching treatment.

Short-term efficacy after switching from adefovir dipivoxil and tenofovir disoproxil fumarate therapy to tenofovir alaferamide for chronic hepatitis B

The aim of the present study was to evaluate the effects of switching to tenofovir alafenamide (TAF) in patients who had received a nucleos(t)ide analog (NA) for the treatment of chronic hepatitis B (CHB). The data from 33 Japanese patients with CHB who received TAF therapy after using NA [adefovir dipivoxil (ADV) and/or tenofovir disoproxil fumarate (TDF)] were retrospectively analyzed. Specifically, the biochemical and virological markers from the start of the TAF treatment to 6 months later were assessed. Comparative evaluation was performed by dividing patients into two groups: Long-term (n=19) and short-term administration groups (n=14), with a cutoff administration duration of 10 years. In all 33 patients, the levels of serum hepatitis B surface antigen (HBsAg; 1,126±1,724 to 1,001±1,591 IU/ml; P<0.0001), serum alkaline phosphatase (ALP) (320±126 to 283±124 U/l; P=0.028), serum bone specific alkaline phosphatase (19.7±9.0 to 17.7±8.0 µg/l; P=0.0006) and urine β2-microglobulin-creatinine ratio (U-BMG/Cr; 5,224±17,471 to 3,547±14,652 µg/g·Cre; P=0.002) significantly decreased from baseline after 6 months. Serum HBsAg, serum ALP and U-BMG/Cr showed a significant reduction in both groups. In conclusion, switching from ADV or TDF to TAF resulted in a decrease in serum HBsAg and improvement in serum ALP and U-BMG/Cr after 6 months of treatment in patients regardless of history of treatment with NA.

Clinical Characteristics of Hepatitis B Virus Patients After Switching to Tenofovir Alafenamide Fumarate: A Retrospective Observational Study

Background

Hepatitis B Virus (HBV) continues to be a significant global health problem despite vaccination programs and effective antiviral drugs.

Aim

Assess tenofovir alafenamide fumarate (TAF) as a new treatment modality in light of the clinical characteristics of HBV patients.

Settings and design

A real-world observational study

Methods and material

We collected data of 71 HBV patients and recorded the hepatitis B virus deoxyribonucleic acid (HBV-DNA) plasma levels and biochemistry test results for the alanine aminotransferase (ALT), aspartate aminotransferase (AST), and serum creatinine levels at three time points, including baseline, time of switching to TAF, and six months after switching.

Results

From the time of switching to TAF till six months later, HBV-DNA plasma levels significantly decreased from 838.61 IU/mL to 16.7 IU/mL (p-value of <0.05). ALT and AST levels dropped from 29.05 U/L to 27 U/L and from 21.34 U/L to 20.7 U/L (p-values 0.328 and 0.410, respectively). Although TAF did not show a statistically significant reduction in the serum levels of AST, ALT, and creatinine, it showed a detectable maintenance level.

Conclusions

In the evaluated cohort, all clinical characteristics of HBV were maintained six months after switching patients to TAF.

Tenofovir alafenamide after switching from entecavir or nucleos(t)ide combination therapy for patients with chronic hepatitis B

BACKGROUND AND AIMS

Tenofovir alafenamide (TAF) has been newly approved for the treatment of chronic hepatitis B (CHB). We aimed to assess the effectiveness and renal safety of switching from entecavir (ETV) or nucleos(t)ide analogue (NA) combination therapy to TAF.

METHODS

This multicentre, retrospective, cohort study included 313 consecutive CHB patients who switched to TAF monotherapy after treatment with ETV or a nucleos(t)ide analogue (NA) combination for over 2 years. Virological/laboratory responses were evaluated for 48 weeks after switchover. Chronic kidney disease (CKD) was defined as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m² . Differences in longitudinal parameters were compared by the generalized estimating equation method.

RESULTS

In the prior ETV group (n = 191), the HBV DNA suppression rate at week 48 was significantly increased, from 75.9% to 96.9% (P < .001). Additionally, mean changes in the HBsAg level at week 48 in HBsAg ≥ 3.0 logIU/mL and < 3.0 logIU/mL groups were -0.09 and -0.13 logIU/mL respectively. In the prior NA combination group (n = 122), the mean changes in HBsAg level at week 48 in the HBsAg ≥ 3.0 logIU/mL and <3.0 logIU/mL groups were -0.08 and -0.11 logIU/mL respectively. For patients with CKD, the eGFR at week 48 was significantly improved compared to those with non-CKD (adjusted slope coefficient difference: 2.75 mL/min/1.73 m² /48 weeks; P = .001).

CONCLUSIONS

Switching from ETV or an NA combination to TAF was effective for HBV suppression and continued HBsAg reduction. Moreover, the renal glomerular function of patients in the prior NA combination group with CKD was significantly improved compared to those with non-CKD.

LAY SUMMARY

Nucleos(t)ide analogues, such as entecavir, tenofovir disoproxil fumarate and tenofovir alafenamide, inhibit hepatitis B virus (HBV) replication and are recommended as first-line oral agents for chronic HBV infection. We evaluated the virological/biochemical effects and renal safety when patients are switched from entecavir or nucleoside-nucleotide analogue combination therapy to tenofovir alafenamide. Our findings suggest that switching to tenofovir alafenamide was effective for HBV suppression and the improvement in renal function for patients with chronic kidney disease.

Comparison of medication adherence and satisfaction between entecavir and tenofovir alafenamide therapy in chronic hepatitis B

Adherence to nucleotide/nucleoside analog therapy is important in improving prognosis in chronic hepatitis B. We aimed to compare medical adherence and satisfaction with entecavir (ETV) and tenofovir alafenamide (TAF) and to assess the effect of switching from ETV to TAF. Patients taking ETV (n = 114) and TAF (n = 35), and who switched from ETV to TAF (n = 15) were included. Medication adherence and satisfaction were assessed using a questionnaire. There was no significant difference in adherence between the ETV and TAF groups, but the medication satisfaction rates (0-10, prefer-dislike) were 1.72 ± 2.2 and 0.69 ± 1.5, respectively (P = .01; significantly higher in the TAF group). In patients who switched from ETV to TAF, medication adherence significantly improved (P = .04) as follows: never forgetting, from 40% to 87%; forgetting once every 2 to 3 months, from 33% to 7%; forgetting once every 2 months, from 20% to 7%, and forgetting once every 4 weeks, from 7% to 0%. Similarly, the medication satisfaction rate significantly improved from 4.53 ± 3.2 to 1.27 ± 2.4 after switching (P = .008). In conclusion, switching from ETV to TAF can be a useful approach to improve medication adherence and satisfaction.

An expert review on the use of tenofovir alafenamide for the treatment of chronic hepatitis B virus infection in Asia

Asia has intermediate-to-high prevalence and high morbidity of hepatitis B virus (HBV) infection. The use of guideline-recommended nucleos(t)ide analogs with high barrier to resistance, such as entecavir (ETV), tenofovir disoproxil fumarate (TDF), and tenofovir alafenamide (TAF), is one of the key interventions for curbing HBV infection and associated morbidity in Asia. However, there are some challenges to the use of ETV and TDF; while ETV is associated with high resistance in lamivudine (LAM)-exposed (especially LAM-refractory) patients; bone and renal safety issues are a major concern with TDF. Hence, a panel of twenty-eight expert hepatologists from Asia convened, reviewed the literature, and developed the current expert opinion-based review article for the use of TAF in the resource-constrained settings in Asia. This article provides a comprehensive review of two large, phase 3, double-blind, randomized controlled trials of TAF versus TDF in HBeAg-negative (study 0108) and HBeAg-positive (study 0110) chronic HBV patients (> 70% Asians). These studies revealed as follows: (1) non-inferiority for the proportion of patients who had HBV DNA < 29 IU/mL; (2) significantly high rate of normalization of alanine aminotransferase levels; (3) no incidence of resistance; and (4) significantly better bone and renal safety, with TAF vs. TDF up to 144 weeks. Considering the benefits of TAF, the expert panel proposed recommendations for optimizing the use of TAF in Asia, along with guidance on specific patient groups at risk of renal or bone disease suitable for TAF therapy. The guidance provided in this article may help clinicians optimize the use of TAF in Asia.

Significance of switching of the nucleos(t)ide analog used to treat Japanese patients with chronic hepatitis B virus infection from entecavir to tenofovir alafenamide fumarate

The significance of switching of the nucleos(t)ide analog used to treat patients with hepatitis B virus (HBV) from entecavir (ETV) to tenofovir alafenamide fumarate (TAF) is uncertain. The subjects of this study were 159 patients with HBV who received treatment with ETV followed by TAF. Among these patients, serial changes in the HBV marker levels were monitored in 92 patients in whom the serum HBsAg levels were ≥100 IU/mL during the 48-week period immediately before and after the switching. A questionnaire survey for medication compliance was performed in 127 patients. The serum HBsAg levels (log IU/mL) decreased by 0.041 during the ETV treatment period and by 0.068 during the TAF administration period. The degree of reduction was higher during the TAF administration period than during the ETV administration period in patients without cirrhosis (P = .030), patients with genotype B HBV (P = .014), and patients with undetectable serum HBcrAg (P = .038). Multivariate analysis revealed the HBV genotype (B vs C; odds ratio, 3.400; P = .025) and serum aspartate aminotransferase level (every 1+; 1.111; P = .015) at the time of switching as factors influencing the treatment efficacy. Thirty-six patients (28%) responded that the number of days that they forgot to take the drug decreased after the drug switching, and 77 patients (61%) reported feeling satisfied with the drug switching. Switching of the nucleos(t)ide analog used from ETV to TAF may be useful in the treatment of patients with HBV infection, as it is associated with both a decrease in the serum HBsAg level and improvement of the medication compliance.

Hepatitis B surface antigen reduction as a result of switching from long-term entecavir administration to tenofovir

Background and Aim

Loss of hepatitis B surface antigen (HBsAg) is an important goal in the treatment of chronic hepatitis B. We investigated whether switching from long‐term entecavir (ETV) administration to tenofovir (TFV) (tenofovir alafenamide [TAF] or tenofovir disoproxil fumarate [TDF]) could contribute to the reduction of HBsAg levels.

Methods

The degree of HBsAg reduction by 48 weeks in 30 patients following switching from ETV to TFV was compared with results from 147 patients who continued ETV as a control.

Results

TFV group switched to TFV after mean 6.79 years of ETV administration. HBV‐DNA levels remained below 1.0 log IU/mL in all cases in both groups during 48 weeks. Median HBsAg reduction at 48 weeks was 0.075 (−0.05 to 0.38) log/IU/mL in the TFV switch group, and 0.070 (−0.28 to 0.50) in the ETV continuation group, which was not statistically significant (p = 0.5). In a subgroup of hepatitis B e antigen negative patients whose HBsAg had not been reduced (HBsAg reduction ≤0 log IU/mL) in the 48 weeks prior to entry into the study, HBsAg reduction was significantly higher in the TFV switch group than in the ETV continuation group (0.15 [0.07–0.135] in TFV, 0.09 [−0.14 to 0.25] log IU/mL in ETV, p = 0.04).

Conclusion

Although HBsAg reduction is equivalent with ETV continuation and switching to TFV in all patients at 48 weeks, switching from ETV to TFV could provide an alternative therapeutic strategy toward HBsAg elimination in a specific subpopulation of patients.