Adverse events of nucleos(t)ide analogues for chronic hepatitis B: a systematic review

Association of nucleos(t)ide analogue therapy with Parkinson disease in chronic hepatitis B patients

Prolonged therapy using nucleos(t)ide analogs (NUC) is inevitable in patients with chronic hepatitis B (CHB) infection, but its long-term impact on Parkinson's disease (PD) risk remains unclear. This study evaluated the association between NUC therapy and PD incidence in a nationwide CHB cohort. The study population comprised the National Health Insurance Service claims database from January 1, 2013, to December 31, 2013, only included treatment naïve CHB patients and those without previously diagnosed with PD. Participants were followed until PD diagnosis or study completion. The primary outcome was PD incidence, comparing patients who initiated NUC therapy at cohort entry with those who did not. Over the 7.9-year study period, the incidence rate of PD in NUC-treated patients was 1.48 per 1000 persons, compared to 1.95 per 1000 persons in the untreated group. In an adjusted competing risk model, the 3-year follow-up showed a statistically significant reduction in risk (hazard ratio [HR]: 0.61; 95% confidence interval [CI] 0.39-0.97). In the propensity score-matched cohort of 18,365 pairs, the cumulative incidence during 2-4 years of follow-up was significantly lower in the NUC-treated group compared to the untreated group. However, no statistically significant difference in cumulative PD incidence was observed between the groups at the early or late stages of the follow-up period. NUC therapy initially reduced PD incidence, but this protective effect diminished over time, indicating a time-varying effect. Regular PD screening may be needed for long-term NUC users.

Impact of nucleos(t)ide analogue therapy on the incidence of Alzheimer's disease in patients with chronic hepatitis B virus infection

BACKGROUND

Long-term therapy with nucleos(t)ide analogs (NUCs) is inevitable for chronic hepatitis B (CHB) patients. However, how NUC therapy on the developing Alzheimer's disease (AD) in these patients remains controversial.

METHODS

This retrospective cohort study used the Korean National Health Insurance Service claims database from January 1, 2013, to December 31, 2013, treatment naïve CHB patients and those without previously diagnosed with AD. Participants were followed from the index date until either the diagnosis of AD or the study's conclusion on December 31, 2021. The primary outcome was the incidence of AD, compared between the group with initiated NUC therapy (n = 18,365) at cohort entry and the group without NUC therapy (n = 212,820).

RESULTS

During the study, 416 patients were diagnosed with AD. After propensity-score matching (18,365 pairs), the 5- to 7-year follow-up showed a significantly lower hazard ratio (HR) in the NUC-treated group compared to the untreated group (HR 0.31-0.40), with HRs remaining constant over time. Subgroup analysis showed more pronounced benefits of NUC therapy in patients under 65 years (HRs: 0.22 vs. 1.23; P < 0.05) and those without dyslipidemia (HRs: 0.14 vs. 1.09; P < 0.05). Protective effects were also observed across subgroups with hypertension, chronic kidney disease, heart disease, and a history of brain trauma, consistent with AD risk factor trends.

CONCLUSIONS

Our study analyses suggest that NUC therapy appears to have a protective effect against the development of AD in patients with CHB.

Higher Relapse Rate in HBeAg-Negative Patients After Cessation of Tenofovir Alafenamide Compared With Entecavir or Tenofovir Disoproxil Fumarate

INTRODUCTION

There is limited information comparing the off-therapy relapse rates of patients discontinued tenofovir alafenamide (TAF) to those stopping entecavir or tenofovir disoproxil fumarate (TDF).

METHODS

A total of 805 hepatitis B e antigen-negative patients without cirrhosis receiving entecavir (n = 406), TDF (n = 260), or TAF (n = 139) were enrolled. Propensity score matching method was applied to eliminate the significant differences in clinical characteristics.

RESULTS

The cumulative incidences of virological relapse, clinical relapse, and retreatment at 96 weeks were higher in the off-TAF group (89.6%, 70.3%, and 59.2%, respectively) than that in the off-entecavir group (65.9%, 42.8%, and 28.8%, respectively) or the off-TDF group (73.7%, 49.8%, and 35.7%, respectively). The median time to clinical relapse was much earlier for off-TAF patients than for off-entecavir or off-TDF (median 14, 57, and 26 weeks, respectively), and these findings persisted even after propensity score matching. Multivariate analysis indicated that TAF therapy was an independent risk factor of virological relapse, clinical relapse, and retreatment when compared with entecavir or TDF. Hepatitis B surface antigen levels at end of treatment were predictive of virological, but not clinical, relapse in the off-TAF group, although this group had a lower rate of severe hepatitis on clinical relapse than the off-TDF group. Finally, there was no significant difference in the hepatic decompensation rate among the entecavir, TDF, and TAF groups.

DISCUSSION

There is an earlier and higher hepatitis B virus relapse rate in patients who discontinue TAF therapy than in comparable patients discontinuing entecavir or TDF therapy. Close monitoring is necessary after TAF withdrawal, particularly in the first 3 months.

Simplified Chronic Hepatitis B Antiviral Initiation Criteria in Thailand: An Economic Evaluation

OBJECTIVES

Criteria for antiviral treatment initiation in Thailand were complex and difficult to implement. This study determined the cost-effectiveness of 2 simplified antiviral treatment initiation criteria among patients with chronic hepatitis B in Thailand.

METHODS

A hybrid model of the decision tree and Markov model was developed. Two simplified antiviral treatment initiation criteria were the expanded criteria, treating patients with hepatitis B surface antigen positive and viral load (hepatitis B virus deoxyribonucleic acid) >2000 IU/mL or cirrhosis by tenofovir alafenamide (TAF), and the test-and-treat criteria, treating patients with hepatitis B surface antigen positive and viral load >10 IU/mL or cirrhosis by TAF. PubMed was searched from its inception to July 2023 to identify input parameters. Best supportive care was chosen for patients who were ineligible for TAF. Incremental cost-effectiveness ratio per quality-adjusted life-year (QALY) was calculated.

RESULTS

The expanded criteria and the test-and-treat could reduce the occurrence of patients progressing to hepatocellular carcinoma. In particular, both criteria could reduce 4846 new cases of hepatocellular carcinoma per 100 000 patients. The incremental cost-effectiveness ratios for the expanded criteria and the test-and-treat criteria were 24 838 Thai baht (THB)/QALY and 163 060 THB/QALY, respectively.

CONCLUSIONS

At the current willingness to pay of 160 000 THB/QALY, the expanded criteria were cost-effective, but the test-and-treat criteria were not cost-effective to be the simplified antiviral treatment initiation criteria for patients with chronic hepatitis B in Thailand.

Effect of nucleos(t)ide analogue discontinuation on the prognosis of HBeAg-negative hepatitis B virus-related hepatocellular carcinoma after hepatectomy: A propensity score matching analysis

BACKGROUND

Although nucleos(t)ide analogues (NAs) are thought to reduce the risk of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC), the effect of NA discontinuation on the prognosis of HBV-related HCC after hepatectomy is rarely reported. We aimed to investigate the potential for hepatitis B virus e antigen (HBeAg)-negative HBV-related HCC patients to discontinue NAs based on preoperative hepatitis B virus surface antigen (HBsAg) status.

METHODS

This historical cohort study involved 1232 NA-treated HBeAg-negative patients who underwent curative hepatectomy for HBV-related HCC from 2014 to 2019. The recurrence-free survival (RFS) and overall survival (OS) of patients discontinuing NAs before surgery were compared with those continuing NAs. Propensity score matching (PSM) was used to balance baseline characteristics.

RESULTS

Of all enrolled patients, 839 (68.1%) patients continued NAs, and 393 (31.9%) patients discontinued NAs. Continuation of NAs was identified as an independent risk factor for RFS (HR 2.047, 95% CI 1.348-3.109, p < 0.001 before PSM and HR 2.756, 95% CI 1.537-4.942, p < 0.001 after PSM) in HBsAg-negative patients. Similarly, subgroup survival analyses showed that NA discontinuation was associated with better RFS (p = 0.029 before PSM and p < 0.001 after PSM) and comparable OS (p = 0.935 before PSM and p = 0.115 after PSM) than NA continuation in HBsAg-negative patients. The interaction between HBsAg status and continuation or discontinuation of NAs was significant (p for interaction <0.001).

CONCLUSIONS

These findings demonstrate the potential for HBeAg-negative HBV-related HCC patients who have achieved HBsAg seroclearance to discontinue NAs under strict monitoring.

Rapid Initiation of Antiretroviral Therapy With Coformulated Bictegravir, Emtricitabine, and Tenofovir Alafenamide Versus Efavirenz, Lamivudine, and Tenofovir Disoproxil Fumarate in HIV-Positive Men Who Have Sex With Men in China: Week 48 Results of the Multicenter, Randomized Clinical Trial

BACKGROUND

Most international treatment guidelines recommend rapid initiation of antiretroviral therapy (ART) for people newly diagnosed with human immunodeficiency virus (HIV)-1 infection, but experiences with rapid ART initiation remain limited in China. We aimed to evaluate the efficacy and safety of efavirenz (400 mg) plus lamivudine and tenofovir disoproxil fumarate (EFV + 3TC + TDF) versus coformulated bictegravir, emtricitabine, and tenofovir alafenamide (BIC/FTC/TAF) in rapid ART initiation among men who have sex with men (MSM) who have been diagnosed with HIV.

METHODS

This multicenter, open-label, randomized clinical trial enrolled MSM aged ≥18 years to start ART within 14 days of confirmed HIV diagnosis. The participants were randomly assigned in a 1:1 ratio to receive EFV (400 mg) + 3TC + TDF or BIC/FTC/TAF. The primary end point was viral suppression (<50 copies/mL) at 48 weeks per US Food and Drug Administration Snapshot analysis.

RESULTS

Between March 2021 and July 2022, 300 participants were enrolled; 154 were assigned to receive EFV + 3TC + TDF (EFV group) and 146 BIC/FTC/TAF (BIC group). At week 48, 118 (79.2%) and 140 (95.9%) participants in the EFV and BIC group, respectively, were retained in care with viral suppression, and 24 (16.1%) and 1 (0.7%) participant in the EFV and BIC group (P < .001), respectively, discontinued treatment because of adverse effects, death, or lost to follow-up. The median increase of CD4 count was 181 and 223 cells/μL (P = .020), respectively, for the EFV and BIC group, at week 48. The overall incidence of adverse effects was significantly higher for the EFV group (65.8% vs 37.7%, P < .001).

CONCLUSIONS

BIC/FTC/TAF was more efficacious and safer than EFV (400 mg) + 3TC + TDF for rapid ART initiation among HIV-positive MSM in China.

Short-Term Efficacy of Tenofovir Alafenamide in Acute-On-Chronic Liver Failure: A Single Center Experience

Background

Patients with acute-on-chronic liver failure (ACLF) who take entecavir (ETV) and tenofovir disoproxil fumarate (TDF) experience a reduction in hepatic events and mortality. The effectiveness of tenofovir alafenamide (TAF) was not well investigated. This study was aim to compare the antiviral efficacy and mortality between TAF and ETV in patients with ACLF caused by the hepatitis B virus (HBV).

Methods

One hundred and six patients with HBV-ACLF who received TAF (25 mg/day) and ETV (0.5 mg/day) for 12 weeks were analyzed. The primary endpoints were overall mortality and liver transplantation (LT) at week 12. Biochemical responses, virologic responses, mortality, drug safety, and side effects were evaluated.

Results

At 4 and 12 weeks of TAF treatment, patients showed significantly higher HBV-DNA reduction (P < .001), higher HBV-DNA undetectability rates (P < .001), and lower HBV DNA levels (P < .001) in serum. Lower Child-Turcotte-Pugh (CTP) scores (P = .003) were observed at 4 weeks in the TAF group, although the CTP scores showed no difference between TAF group and ETV group at 12 weeks (P = 1.143). Lower alanine aminotransferase (ALT) levels of patients in the TAF group at week 4 and 12 were observed (P = .023 and P < .0001, separately). The mortality of TAF group was lower after 4 weeks of treatment (P = .038); however, the 2 groups had similar mortality rates at week 8 and 12. Among the causes of death in HBV-ACLF patients, we found the same incidence of liver-related problems in both groups (P > .05).

Conclusions

This study showed that ACLF patients with chronic HBV infection treated with TAF had a rapid decline in HBV DNA, a higher rate of ALT reduction and improved CTP scores compared to the ETV group, thereby improving patient survival.

Patient Preferences and Their Influence on Chronic Hepatitis B-A Review

Chronic hepatitis B (CHB) is a common chronic viral infectious disease that requires long-term treatment to control the condition and prevent complications. To standardize treatment regimens for CHB, professional associations have established relevant guidelines, but they have often overlooked patient preferences. Historically, in the treatment process, medical decisions were predominantly made by physicians or health care administrators, with limited patient involvement, leading to the neglect of patient preferences. Patient attitudes, expectations, and needs are all influenced by their preferences, and patient preferences have a direct impact on treatment adherence. Understanding and respecting patient preferences are crucial to ensuring treatment effectiveness. This article will explore patient preferences in the treatment of CHB and elucidate the influence of patient preferences on treatment adherence, aiming to provide insights for the development of a more personalized and effective health care process.

HBV reactivation in patients with rheumatoid arthritis treated with anti-interleukin-6: a systematic review and meta-analysis

OBJECTIVE

The objective of this study was to assess the possibility of HBV reactivation (HBVr) in patients with RA under anti-IL-6 treatment.

METHODS

Using PubMed, Scopus and EMBASE, we performed a systematic literature search for articles related to HBVr in RA patients under anti-IL-6 treatment. The search was performed with no date limits and was last updated 28 January 2023. The results from all the databases were combined and duplicates were excluded, as were non-English articles, case reports, position articles, comments, and paediatric studies.

RESULTS

Our initial search led to 427 articles; 28 were duplicates, 46 non-English, 169 reviews, 31 books/letters, 25 case reports, and 88 irrelevant to the meta-analysis aim; 21 were excluded due to inadequate information, leaving 19 articles, with a sum of 372 RA patients with chronic HBV (CHB) or resolved HBV infection, for further analysis. The overall risk for HBVr in RA patients with CHB was 6.7%, increasing to 37% when only RA patients with CHB and no antiviral prophylaxis were included. On the contrary, HBVr was close to 0% in RA patients with resolved HBV infection, irrespective of antiviral prophylaxis. All RA patients experiencing HBVr in these studies were successfully managed with antiviral treatment and/or drug withdrawal.

CONCLUSION

Overall, anti-IL-6 treatment comes with a significant risk of HBVr in RA patients with CHB; risk is diminished when antiviral prophylaxis is used. In contrast, in RA patients with resolved HBV infection, the risk of HBVr seems to be extremely low. Large, well-designed studies (either controlled trials or multicentre/international observational studies) are warranted to further validate these results.

Development of Therapy Based on the Exploration of Biological Events Underlying the Pathogenetic Mechanisms of Chronic Hepatitis B Infection

According to the World Health Organization (WHO), an estimated 296 million people are chronically infected with hepatitis B virus (HBV). Approximately 15-25% of these people develop complications such as advanced chronic liver diseases (ACLDs). Mortality due to HBV-related complications accounted for an estimated 882,000 deaths in 2019. Potent preventive vaccines have already restricted new HBV infections, and several drugs are available to treat chronic HBV infections. However, the positive impacts of these drugs have been recorded in only a few patients with chronic HBV infection. These drugs do not show long-term efficacy and cannot halt the progression to complications. Thus, more effective and evidence-based therapeutic strategies need to be urgently developed for patients with chronic HBV infection. CHB is a pathological entity induced by HBV that progresses due to impaired host immunity. This indicates the inherent limitations of antiviral-drug-based monotherapy for treating patients with chronic HBV infection. Additionally, commercially available antiviral drugs are not available to patients in developing and resource-constrained countries, posing a challenge to achieving the following WHO goal: "Elimination of Hepatitis by 2030". As such, this review aimed to provide insights regarding evidence-based and effective management strategies for chronic HBV infection.

Global importance of new treatment strategies to efforts to control hepatitis B virus

INTRODUCTION

Hepatitis B Virus (HBV) infection can progress to chronic HBV (CHB) disease, thereby increasing the risk of severe forms of liver disease (i.e. liver cirrhosis and hepatocellular carcinoma) and resulting in a high global burden of morbidity, mortality, and health-care utilization.

AREAS COVERED

We discuss how future therapeutic strategies and treatment guidelines may address the large unmet medical needs among patients with CHB.

EXPERT OPINION

Complexity and a lack of consensus in current CHB treatment guidelines may limit their effective implementation. To minimize poor outcomes in patients not currently receiving treatment (including immune-tolerant and inactive carriers), a simplified harmonized treatment approach is needed across guidelines. Current treatment recommendations focus on nucleot(s)ide analogs (NAs) and pegylated interferon (Peg-IFN), both of which have limitations. NAs provide clinical benefits, but treatment is prolonged and has little impact on functional cure rates. Peg-IFN offers the potential for functional cure but has notable safety and tolerability issues. A shift toward finite treatments with acceptable safety and tolerability profiles is needed.

CONCLUSION

The key to achieving World Health Organization targets for the global eradication of HBV involves enhanced diagnosis with new treatments and/or combinations of existing treatments alongside globally aligned and simplified treatment guidelines for untreated/inadequately treated populations.

Risk prediction algorithms in guiding antiviral therapy initiation among patients with chronic hepatitis B in Thailand: an economic evaluation and budget impact analysis

OBJECTIVE

Several risk prediction algorithms have been developed to guide antiviral therapy initiation among patients with chronic hepatitis B (CHB). This study assessed the cost-effectiveness and budget impact of three risk prediction algorithms among patients with CHB in Thailand.

METHODS

A decision tree with a Markov model was constructed. Three risk prediction algorithms were compared with current practices including HePAA, TREAT-B and REACH-B. PubMed was searched from its inception to December 2022 to identify inputs. Tenofovir alafenamide and best supportive care were selected for antiviral-eligible patients, and incremental cost-effectiveness ratios per quality-adjusted life year (QALY) were calculated.

RESULTS

Our base case analysis showed that HePAA and REACH-B could provide better QALY (0.098 for HePAA and 0.921 for REACH-B) with decreased total healthcare costs (-10909 THB for HePAA and -8,637 THB for REACH-B). TREAT-B provided worse QALY (-0.144) with increased total healthcare costs (10,435 THB). The budget impacts for HePAA and REACH-B were 387 million THB and 3,653 million THB, respectively.

CONCLUSION

HePAA and REACH-B algorithms are cost-effective in guiding antiviral therapy initiation. REACH-B is the most cost-effective option, but has a high budget impact. Policymakers should consider both cost-effectiveness and budget impact findings when deciding which algorithm should be implemented.

The Efficacy of Antiviral Treatment for Chronic Hepatitis B Patients with Normal ALT Levels: A Systematic Review and Meta-analysis

Context: When nucleos(t)ide analogues (NAs) were applied clinically to manage chronic hepatitis B virus infection, the prognosis of chronic hepatitis B (CHB) patients greatly improved. However, certain CHB patients with normal alanine aminotransferase (ALT) levels were not used to be considered as the population with the need for antiviral treatment. Objectives: This systematic review and meta-analysis collected and analyzed data from clinical trials to assess and compare the efficacy of antiviral treatment among patients with elevated and normal ALT levels. Methods: A systematic search was performed to gather studies published from 1990.01 to 2022.08 in PubMed and Web of Science databases. The quality of the literature was assessed, and 16 studies were included for further analysis. Basic information on included studies and study populations was collected. A meta-analysis was carried out to evaluate three major outcomes of viral response, hepatitis B envelope antigen (HBeAg) loss, and HBeAg seroconversion after NAs treatment based on data extracted from these studies. Odds ratios (ORs) with 95% confidence intervals (CIs) for all outcomes were calculated using fixed-effects models. Results: In the 16 relevant studies, 5,345 patients met the inclusion criteria, including 3,687 patients receiving NAs treatment. All patients were grouped into one with elevated ALT and another with normal ALT based on whether their pretreatment ALT levels > 1*upper limit of normal (ULN). For patients receiving lamivudine, the viral response showed no significant difference between the groups with elevated and normal ALT levels (pooled log OR: 0.51 [-0.23 - 1.26], P = 0.79); the pooled log OR for HBeAg loss was 1.19 (0.63 - 1.76, P = 0.03) and pooled log OR for HBeAg seroconversion was 2.19 (0.91 - 3.47, P = 0.40). For patients receiving first-line therapy with tenofovir disoproxil fumarate (TDF) and entecavir (ETV), the viral response showed no significant difference between the two groups: Pooled log OR (0.38 [-0.22 - 0.97], P = 0.10). The pooled log OR for HBeAg loss and HBeAg seroconversion was (-0.07 [-0.81 - 0.67], P = 0.68) and (0.40 [-0.84 - 1.63], P = 0.88), respectively. Conclusions: The efficacies of first-line therapy with TDF and ETV treatments were similar in groups with elevated and normal ALT levels for the outcomes of viral response and HBeAg loss. These findings may support further treatment of CHB patients with normal ALT levels.

Development of Therapeutic Vaccine for Chronic Hepatitis B: Concept, Cellular and Molecular Events, Design, Limitation, and Future Projection

Four decades have passed since the first usage of the therapeutic vaccine in patients with chronic hepatitis B (CHB). However, there is no approved regimen of vaccine therapy for the treatment of CHB. This is mainly attributable to faulty conception, an improper understanding of the cellular and molecular mechanisms of CHB, and the impaired design of vaccine therapy for CHB. With the advent of new techniques and a better understanding of cellular and molecular mechanisms underlying the genesis of CHB, the limitations and failures of previous regimens of therapeutic vaccines have been primarily understood. Additionally, the importance of immune therapy for treating millions of CHB patients and achieving the target of "Elimination of Hepatitis by 2030" has been focused on in the international arena. This has been amplified by the apparent limitation of commercially available antiviral drugs that are infinite in duration, endowed with safety concerns, and unable to cure liver damage due to their minimal immune modulation capacities. The proposed review article comprehensively discusses each of these points and proposes evidence-based approaches for viable types of vaccine therapy for the treatment of CHB.

Economic Evaluation of Oral Nucleos(t)ide Analogues for Patients with Chronic Hepatitis B in Thailand

BACKGROUND

Nucleos(t)ide analogues (NAs) are the main drug category used in the treatment of chronic hepatitis B (CHB). There is a need to update the economic evaluation of CHB treatment.

OBJECTIVE

This study aimed to determine the cost effectiveness of NAs for CHB in Thailand.

METHOD

We used a lifetime Markov model undertaken from a societal perspective. Tenofovir disoproxil fumarate (TDF), tenofovir alafenamide fumarate (TAF), entecavir (ETV) with TDF or TAF as rescue medications, and lamivudine (LAM) with TDF or TAF rescue medications were compared with best supportive care (BSC). We performed a network meta-analysis to estimate the treatment effects of each NA on hepatitis B surface antigen (HBsAg) loss in an Asian population and performed an additional literature review to identify inputs. We calculated incremental cost-effectiveness ratios (ICERs) per quality-adjusted life-years (QALYs) and performed sensitivity analyses.

RESULTS

Compared with BSC, all NAs could improve patients' QALYs, with results ranging from 4.04 to 4.25 QALYs gained. TAF, TDF, LAM/TAF, and LAM/TDF yielded lower total lifetime costs than BSC, ranging from - $US1387 to - 814, whereas ETV/TAF and ETV/TDF yielded higher total lifetime costs than BSC, ranging from $US4965 to 4971. The ICER was $US1230/QALY for ETV/TDF and $US1228/QALY for ETV/TAF. Full incremental analysis showed that the ICER for LAM/TAF was $US1720/QALY compared with TAF.

CONCLUSION

At current prices, TAF, TDF, LAM/TAF, and LAM/TDF are dominant options, and ETV/TAF or ETV/TDF are cost-effective options. LAM/TAF is the most cost-effective option, followed by TAF.

Innovative Therapies Targeting the Virus and the Host for Treating Chronic Hepatitis B Virus Infection: From Bench to Bedside

Chronic hepatitis B (CHB) is a highly complicated pathological process in which the disease is initiated by the hepatitis B virus (HBV); however, host immune responses are primarily responsible for variable extents of liver damage. If the patients with CHB remain untreated, many CHB patients will eventually develop complications like cirrhosis of the liver (LC) and hepatocellular carcinoma (HCC). In 2019, an estimated 882,000 patients died due to HBV-related complications worldwide. Accordingly, several drugs with antiviral properties have been used to treat CHB patients during the last four decades. However, the treatment outcome is not satisfactory because viral suppression is not usually related to the containment of progressive liver damage. Although proper reconstruction of host immunity is essential in CHB patients, as of today, there is no acceptable immune therapeutic protocol for them. These realities have exposed new, novel, and innovative therapeutic regimens for the management of CHB patients. This review will update the scope and limitation of the different innovative antiviral and immune therapeutic approaches for restoring effective host immunity and containing the virus in CHB patients to block progression to LC and HCC.

Immune therapies against chronic hepatitis B

Patients with chronic hepatitis B (CHB) represent a living and permanent reservoir of hepatitis B virus (HBV). Millions of these CHB patients will eventually develop complications such as liver cirrhosis, hepatic failure, and hepatocellular carcinoma if they are not treated properly. Accordingly, several antiviral drugs have been developed for the treatment of CHB, but these drugs can neither eradicate all forms of HBV nor contain the progression of complications in most patients with CHB. Thus, the development of new and novel therapeutics for CHB remains a pressing need. The molecular and cellular mechanisms underlying the pathogenesis of CHB indicate that immune dysregulations may be responsible for HBV persistence and progressive liver damage in CHB. This provided the scientific and ethical basis for the immune therapy of CHB patients. Around 30 years have passed since the initiation of immune therapies for CHB in the early 1990s, and hundreds of clinical trials have been accomplished to substantiate this immune treatment. Despite these approaches, an acceptable regimen of immune therapy is yet to be realized. However, most immune therapeutic agents are safe for human usage, and many of these protocols have inspired considerable optimism. In this review, the pros and cons of different immune therapies, observed in patients with CHB during the last 30 years, will be discussed to derive insights into the development of an evidence-based, effective, and patient-friendly regimen of immune therapy for the treatment of CHB.

Tenofovir-induced renal and bone toxicity: report of two cases and literature review

Tenofovir Disoproxil Fumarate (TDF) is one of the drugs in the initial first-line antiretroviral regimen for the treatment of hepatitis B and HIV infections. Despite its effectiveness and few adverse effects, it is related to renal and bone toxicity. We described two cases of HIV-positive middle-aged women who had been using TDF for two and four years (cases 1 and 2, respectively) and were admitted to the emergency room. Case 1 presented with metabolic ileum and diffuse bone pain while case 2 presented with bilateral coxo-femoral pain after a fall from standing height. Both cases had similar laboratory tests: hyperchloremic metabolic acidosis, hypophosphatemia, hypokalemia, hypouricemia and elevated plasma creatinine. In urinary exams, there was evidence of renal loss of electrolytes, justifying the serum alterations, in addition to glucosuria and proteinuria. The bone pain investigation identified bone fractures and reduced bone mineral density, together with increased levels of parathyroid hormone, alkaline phosphatase and vitamin D deficiency. These two cases illustrate the spectrum of adverse renal and bone effects associated with TDF use. TDF was discontinued and treatment was focused on correcting the electrolyte disturbances and acidosis, in addition to controlling the bone disease through vitamin D and calcium supplementation. The renal changes found in both cases characterized the Fanconi’s syndrome, and occurred due to TDF toxicity to proximal tubule cells mitochondria. Bone toxicity occurred due to direct interference of TDF in bone homeostasis, in addition to vitamin D deficiency and phosphaturia resulting from tubulopathy. During the follow-up, both cases evolved with chronic kidney disease and in one of them, the Fanconi’s syndrome did not revert. We emphasize the need to monitor markers of bone metabolism and glomerular and tubular functions in patients using TDF.

Phosphonates and Phosphonate Prodrugs in Medicinal Chemistry: Past Successes and Future Prospects

Compounds with a phosphonate group, i.e., -P(O)(OH)₂ group attached directly to the molecule via a P-C bond serve as suitable non-hydrolyzable phosphate mimics in various biomedical applications. In principle, they often inhibit enzymes utilizing various phosphates as substrates. In this review we focus mainly on biologically active phosphonates that originated from our institute (Institute of Organic Chemistry and Biochemistry in Prague); i.e., acyclic nucleoside phosphonates (ANPs, e.g., adefovir, tenofovir, and cidofovir) and derivatives of non-nucleoside phosphonates such as 2-(phosphonomethyl) pentanedioic acid (2-PMPA). Principal strategies of their syntheses and modifications to prodrugs is reported. Besides clinically used ANP antivirals, a special attention is paid to new biologically active molecules with respect to emerging infections and arising resistance of many pathogens against standard treatments. These new structures include 2,4-diamino-6-[2-(phosphonomethoxy)ethoxy]pyrimidines or so-called "open-ring" derivatives, acyclic nucleoside phosphonates with 5-azacytosine as a base moiety, side-chain fluorinated ANPs, aza/deazapurine ANPs. When transformed into an appropriate prodrug by derivatizing their charged functionalities, all these compounds show promising potential to become drug candidates for the treatment of viral infections. ANP prodrugs with suitable pharmacokinetics include amino acid phosphoramidates, pivaloyloxymethyl (POM) and isopropoxycarbonyloxymethyl (POC) esters, alkyl and alkoxyalkyl esters, salicylic esters, (methyl-2-oxo-1,3-dioxol-4-yl) methyl (ODOL) esters and peptidomimetic prodrugs. We also focus on the story of cytostatics related to 9-[2-(phosphonomethoxy)ethyl]guanine and its prodrugs which eventually led to development of the veterinary drug rabacfosadine. Various new ANP structures are also currently investigated as antiparasitics, especially antimalarial agents e.g., guanine and hypoxanthine derivatives with 2-(phosphonoethoxy)ethyl moiety, their thia-analogues and N-branched derivatives. In addition to ANPs and their analogs, we also describe prodrugs of 2-(phosphonomethyl)pentanedioic acid (2-PMPA), a potent inhibitor of the enzyme glutamate carboxypeptidase II (GCPII), also known as prostate-specific membrane antigen (PSMA). Glutamate carboxypeptidase II inhibitors, including 2-PMPA have been found efficacious in various preclinical models of neurological disorders which are caused by glutamatergic excitotoxicity. Unfortunately its highly polar character and hence low bioavailability severely limits its potential for clinical use. To overcome this problem, various prodrug strategies have been used to mask carboxylates and/or phosphonate functionalities with pivaloyloxymethyl, POC, ODOL and alkyl esters. Chemistry and biological characterization led to identification of prodrugs with 44-80 fold greater oral bioavailability (tetra-ODOL-2-PMPA).

Challenges in the discontinuation of chronic hepatitis B antiviral agents

Long-term antiviral treatment of chronic hepatitis B patients has been proven to be beneficial in reducing liver-related complications. However, lengthy periods of daily administration of medication have some inevitable drawbacks, including decreased medication adherence, increased cost of treatment, and possible long-term side effects. Currently, discontinuation of antiviral agent has become the strategy of interest to many hepatologists, as it might alleviate the aforementioned drawbacks and increase the probability of achieving functional cure. This review focuses on the current evidence of the outcomes following stopping antiviral treatment and the factors associated with subsequent hepatitis B virus relapse, hepatitis B surface antigen clearance, and unmet needs.

Review of Current and Potential Treatments for Chronic Hepatitis B Virus Infection

Chronic hepatitis B virus (HBV) infection remains a major global health burden. Millions of people are at risk for complications of chronic HBV infection, despite the widespread availability of an effective prophylactic vaccine. The current available treatments for HBV infection-interferon and nucleos(t)ide analogues-are effective at suppressing viral replication and decreasing the risk of cirrhosis. However, these treatments have a number of limitations, creating the need for alternative therapeutic agents. Recent advances in drug therapy have heralded a new horizon of novel therapeutic approaches for chronic HBV infection, with several promising antiviral and immunomodulatory agents currently in preclinical or clinical testing. This article reviews the current landscape of HBV treatments and highlights the most recent therapeutic strategies designed to directly target HBV or to improve immune response during chronic infection.

Effect of comprehensive nursing on the pain, anxiety and malnutrition of hepatitis B patients

OBJECTIVE

To explore the effect of comprehensive nursing on pain, anxiety and malnutrition of hepatitis B patients.

METHODS

Totally 100 cases of hepatitis B patients received treatment in our hospital from July 2017 to July 2018 were divided into a study group (64 cases) and a control group (36 cases) for comprehensive nursing and routine nursing. The liver function, nutritional indexes, cognition of relevant nursing knowledge, VAS score, HAMD and HAMA scores, QOL score, total effective rate and incidence of adverse reactions were detected.

RESULTS

Compared with the control group, the study group had lower liver function indexes and higher nutrition indexes, suggesting that the liver function of patients in the study group recovered better. Besides, the VAS score of the study group was lower, suggesting better pain relief in the study group. Moreover, the study group had higher scores of related nursing knowledge and lower scores of HAMD and HAMA, indicating that the nursing method in the study group was more effective in reducing depression and anxiety. Higher QOL score, higher total effective rate and lower incidence of adverse reactions of the study group revealed that the nursing mode adopted in this group was better for the recovery of patients.

CONCLUSION

Comprehensive nursing can effectively alleviate the pain of hepatitis B patients, relieve their anxiety and other negative emotions, and improve their malnutrition.

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.

Drug Discovery of Nucleos(t)ide Antiviral Agents: Dedicated to Prof. Dr. Erik De Clercq on Occasion of His 80th Birthday

Nucleoside and nucleotide analogues are essential antivirals in the treatment of infectious diseases such as human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), herpes simplex virus (HSV), varicella-zoster virus (VZV), and human cytomegalovirus (HCMV). To celebrate the 80th birthday of Prof. Dr. Erik De Clercq on 28 March 2021, this review provides an overview of his contributions to eight approved nucleos(t)ide drugs: (i) three adenosine nucleotide analogues, namely tenofovir disoproxil fumarate (Viread^®) and tenofovir alafenamide (Vemlidy^®) against HIV and HBV infections and adefovir dipivoxil (Hepsera^®) against HBV infections; (ii) two thymidine nucleoside analogues, namely brivudine (Zostex^®) against HSV-1 and VZV infections and stavudine (Zerit^®) against HIV infections; (iii) two guanosine analogues, namely valacyclovir (Valtrex^®, Zelitrex^®) against HSV and VZV and rabacfosadine (Tanovea^®-CA1) for the treatment of lymphoma in dogs; and (iv) one cytidine nucleotide analogue, namely cidofovir (Vistide^®) for the treatment of HCMV retinitis in AIDS patients. Although adefovir dipivoxil, stavudine, and cidofovir are virtually discontinued for clinical use, tenofovir disoproxil fumarate and tenofovir alafenamide remain the most important antivirals against HIV and HBV infections worldwide. Overall, the broad-spectrum antiviral potential of nucleos(t)ide analogues supports their development to treat or prevent current and emerging infectious diseases worldwide.

Moving Fast Toward Hepatitis B Virus Elimination

Currently, there are two safe and effective therapeutic strategies for chronic hepatitis B treatment, namely, nucleoside analogs and interferon alpha (pegylated or non-pegylated). These treatments can control viral replication and improve survival; however, they do not eliminate the virus and therefore require long-term continued therapy. In addition, there are significant concerns about virus rebound on discontinuation of therapy and the development of fibrosis and hepatocellular carcinoma despite therapy. Therefore, the search for new, more effective, and safer antiviral agents that can cure hepatitis B virus (HBV) continues. Anti-HBV drug discovery and development is fundamentally impacted by our current understanding of HBV replication, disease physiopathology, and persistence of HBV covalently closed circular DNA (cccDNA). Several HBV replication targets are the basis for novel anti-HBV drug development strategies. Many of them are already in clinical trial phase 1 or 2, while others with promising results are still in preclinical stages. As research intensifies, potential HBV curative therapies and modalities in the pipeline are now on the horizon.

Secondary prevention for hepatocellular carcinoma in patients with chronic hepatitis B: are all the nucleos(t)ide analogues the same?

Reducing the incidence of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB) is the key ultimate goal set in essentially all treatment guidelines. There has been solid evidence supporting the relationship between serum hepatitis B virus (HBV) DNA level and risk of HCC. Antiviral treatment with oral nucleos(t)ide analogues (NAs) leads to sustained viral suppression and hence is often adopted as the secondary prevention for HCC in CHB patients. The first-generation NA, lamivudine, reduced the risk of HCC at 3 years compared to placebo; yet, its high emergence of antiviral resistance has made it no longer recommended in the international guidelines. Recent heated debate is about the two current first-line NAs-entecavir and tenofovir disoproxil fumarate (TDF)-Are they just as good to reduce HCC risk in CHB patients? A handful of cohort studies show two different kinds of observations-TDF is better than entecavir in lowering HCC risk, or these two NAs have led to similarly low risk of HCC. Tenofovir alafenamide (TAF), a modified version of TDF higher rate of ALT normalization, would be another potent nucleotide analogue is the treatment of choice for secondary prevention for HCC.

HBV replication inhibitors

Chronic Hepatitis B Virus infections afflict >250 million people and kill nearly 1 million annually. Current non-curative therapies are dominated by nucleos(t)ide analogs (NAs) that profoundly but incompletely suppress DNA synthesis by the viral reverse transcriptase. Residual HBV replication during NA therapy contributes to maintenance of the critical nuclear reservoir of the HBV genome, the covalently-closed circular DNA, and to ongoing infection of naive cells. Identification of next-generation NAs with improved efficacy and safety profiles, often through novel prodrug approaches, is the primary thrust of ongoing efforts to improve HBV replication inhibitors. Inhibitors of the HBV ribonuclease H, the other viral enzymatic activity essential for viral genomic replication, are in preclinical development. The complexity of HBV's reverse transcription pathway offers many other potential targets. HBV's protein-priming of reverse transcription has been briefly explored as a potential target, as have the host chaperones necessary for function of the HBV reverse transcriptase. Improved inhibitors of HBV reverse transcription would reduce HBV's replication-dependent persistence mechanisms and are therefore expected to become a backbone of future curative combination anti-HBV therapies.