Extrahepatic carcinogenicity of oral nucleos(t)ide analogues in chronic hepatitis B carriers: A 35,000-Korean outcome study.

Evidence on the carcinogenicity of oral nucleos(t)ide analogues (NAs) is inconclusive and lacks data on the effects by chemical structure of the NAs in patients with chronic hepatitis B (CHB). We aimed to provide definitive results on this issue using a large set of CHB patients and data on all major NA drugs. The study population consisted of 10,331 patients with CHB receiving primary NA treatment for more than 6 months, and 24,836 untreated controls followed for at least as long as the treated patients. Using the inverse-probability-of-treatment-weighted (IPTW) method, the cumulative incidence of extrahepatic cancers was compared in the treated and untreated patients and across the cyclopentane, L-nucleoside and acyclic phosphonate categories of NAs. Analyses of individual cancers as sub-endpoints were also performed. The cumulative incidence of overall extrahepatic malignancies did not differ between the two groups in the IPTW cohort (hazard ratio [HR] 1.002; 95% confidence interval [CI] [0.859-1.169]). Similar statistical trends were observed in analyses across the three NA chemical subsets and controls. Per-cancer analyses indicated that NA treatment was significantly associated with increased risks of colorectal/anal cancers (HRs [95% CI], 1.538 [1.175-2.013]) and lymphoma (1.784 [1.196-2.662]). Conversely, breast cancer (HRs [95% CI], 0.669 [0.462-0.967]) and prostate cancer (0.521 [0.329-0.825]) were less prevalent in the NA-treated group. In conclusion, prolonged NA treatment presents carcinogenic risks for colorectal/anal and lymphoid tissues in CHB patients, although it does not affect most extrahepatic organs. The protective effect of NAs on breast and prostate cancers should be confirmed.

Ongoing viral replication and production of infectious virus in patients with chronic hepatitis B virus suppressed below the limit of quantitation on long-term nucleos(t)ide therapy.

Nucleos(t)ide analogs are standard-of-care for the treatment of chronic hepatitis B and can effectively reduce hepatitis B virus (HBV) replication but rarely leads to cure. Nucleos(t)ide analogs do not directly eliminate the viral episome, therefore treatment cessation typically leads to rapid viral rebound. While treatment is effective, HBV DNA is still detectable (although not quantifiable) in the periphery of the majority of nucleos(t)ide analog treated HBV patients, even after prolonged treatment. Addressing whether the detectable HBV DNA represents infectious virus is a key unknown and has important implications for the development of a curative treatment for HBV. The minimum HBV genome equivalents required to establish infection in human liver chimeric mice was determined by titration of HBV patient sera and the infectivity in chimeric mice of serum from patients (n = 7) suppressed to the limit of detection on nucleos(t)ide analog therapy was evaluated. A minimum of 5 HBV genome equivalents were required to establish infection in the chimeric mice, confirming this model has sufficient sensitivity to determine whether serum from virally suppressed patients contains infectious virus. Strikingly, serum from 75% (n = 3 out of 4) of nucleos(t)ide-treated HBV patients with DNA that was detectable, but below the lower limit of quantitation, also established infection in the chimeric mice. These results demonstrate that infectious virus is still present in some HBV patients on suppressive nucleos(t)ide therapy. This residual virus may support viral persistence via continuous infection and explain the ongoing risk for HBV-related complications despite long-term suppression on therapy. Thus, additional treatment intensification may facilitate HBV cure.

Herpes Zoster Following a Nucleoside-Modified Messenger RNA COVID-19 Vaccine.

Herpes zoster (HZ) was suspected as a predictive cutaneous manifestation of COVID-19, with a debated prognostic significance. We report a series of 5 cases of HZ occurring after vaccination with a nucleoside-modified messenger RNA (mRNA) COVID-19 vaccine (Comirnaty, Pfizer-BioNTech). These new cases do not prove causality between COVID-19 vaccination and HZ. The pathophysiologic mechanism remains elusive, but local vaccine-induced immunomodulation may be involved. The occurrence of HZ does not justify avoiding the second injection of vaccine due to the benefit of vaccination.

Human genetic risk of treatment with antiviral nucleoside analog drugs that induce lethal mutagenesis: The special case of molnupiravir.

This review considers antiviral nucleoside analog drugs, including ribavirin, favipiravir, and molnupiravir, which induce genome error catastrophe in SARS-CoV or SARS-CoV-2 via lethal mutagenesis as a mode of action. In vitro data indicate that molnupiravir may be 100 times more potent as an antiviral agent than ribavirin or favipiravir. Molnupiravir has recently demonstrated efficacy in a phase 3 clinical trial. Because of its anticipated global use, its relative potency, and the reported in vitro "host" cell mutagenicity of its active principle, ß-d-N4-hydroxycytidine, we have reviewed the development of molnupiravir and its genotoxicity safety evaluation, as well as the genotoxicity profiles of three congeners, that is, ribavirin, favipiravir, and 5-(2-chloroethyl)-2'-deoxyuridine. We consider the potential genetic risks of molnupiravir on the basis of all available information and focus on the need for additional human genotoxicity data and follow-up in patients treated with molnupiravir and similar drugs. Such human data are especially relevant for antiviral NAs that have the potential of permanently modifying the genomes of treated patients and/or causing human teratogenicity or embryotoxicity. We conclude that the results of preclinical genotoxicity studies and phase 1 human clinical safety, tolerability, and pharmacokinetics are critical components of drug safety assessments and sentinels of unanticipated adverse health effects. We provide our rationale for performing more thorough genotoxicity testing prior to and within phase 1 clinical trials, including human PIG-A and error corrected next generation sequencing (duplex sequencing) studies in DNA and mitochondrial DNA of patients treated with antiviral NAs that induce genome error catastrophe via lethal mutagenesis.

Insufficient immunity led to virologic breakthrough in NAs-treated chronic hepatitis B patients switching to Peg-IFN-ɑ.

BACKGROUND: Virologic breakthrough (VBT) may occur in chronic hepatitis B (CHB) patients after switching from nucleos(t)ide analogues (NAs) to pegylated interferon alpha (Peg-IFN-ɑ). This study aimed to characterize the clinical and immunological features of VBT. METHODS: In NAs-treated patients switching to Peg-IFN-ɑ, innate and adaptive immune cell proportions were examined in peripheral blood and liver biopsy specimens. In vitro effect of IFN-ɑ on the expressions of toll-like receptors 2 (TLR2) and programmed cell death ligand 1 (PDL1) on monocytes, programmed cell death 1 (PD1) on CD8+T cells was examined. Peripheral blood mononuclear cells (PBMCs) were treated with TLR2 agonist and/or PDL1 blockade to evaluate their effect on HBV replication. RESULTS: 33 of 166 patients switching to Peg-IFN-ɑ experienced VBT after NA cessation, with majority being hepatitis B e antigen (HBeAg) positive or having higher hepatitis B core-related antigen (HBcrAg) levels. Patients with VBT exhibited lower proportions of TLR2+monocyte and increased PD1+HBV-specific CD8+T cell during the early phase of Peg-IFN-ɑ therapy after NA cessation in peripheral blood, as well as fewer TLR2+CD68+macrophages but more PDL1+CD68+macrophages and PD1+CD8+T cells in liver tissues. Simultaneous use of TLR2 agonist and PDL1 blockage ex vivo suppressed HBV replication by promoting cytokines production and CD8+T cells cytotoxicity. Upon in vitro IFN-ɑ stimulation, PDL1+monocytes and PD1+CD8+T cells were upregulated, whereas TLR2+monocytes were not increased in PBMC isolated from HBeAg-positive patients, or those with high HBcrAg titers. CONCLUSIONS: In NAs-treated patients, lower TLR2+monocyte and increased PD1+HBV-specific CD8+T cell proportions potentially contribute to VBT after switching to Peg-IFN-ɑ therapy. This insufficient immunity may be associated with the HBeAg status and HBcrAg levels.

Severe Acute Exacerbation After Cessation of Nucleos(t)ide Analog for Chronic Hepatitis B: A Real-World Study of Routine Practice.

There is an ongoing debate as to whether patients with chronic hepatitis B (CHB) may discontinue nucleos(t)ide analogue (NA) therapy before seroclearance of hepatitis B surface antigen (HBsAg).1 Whereas treatment discontinuation may facilitate HBsAg seroclearance and avoid indefinite drug exposure,2 reactivation of viral replication almost always follows treatment cessation and frequently leads to clinical flares.3 In patients who encounter withdrawal flares, severe acute exacerbation (SAE) could occur with fatal consequences.4 Quantitative knowledge about the risk of SAE is imperative to inform the debate and also the practice.

Inappropriate cessation of nucleos(t)ide analog associated with reduced liver transplant-free survival in patients with HBV-related acute on chronic liver failure.

The inappropriate cessation of nucleos(t)ide analog (NA) therapy may lead to acute exacerbations of chronic hepatitis B virus (HBV) infection, acute-on-chronic liver failure (ACLF), and even death. This study aims to elucidate the association between inappropriate NA cessation and prognosis in patients with HBV-ACLF. A total of 901 patients with ACLF were enrolled and stratified into inappropriate NA cessation and non-NA cessation group. Clinical characteristics and prognosis between the two groups were compared. The association between inappropriate NA cessation and the prognosis of patients with HBV-ACLF was evaluated using Cox proportional hazard models after propensity score matching (PSM). NA cessation was identified in 132 patients (NA cessation group), while 769 patients were triggered by other factors (non-NA cessation group). The 28- and 90-day liver transplant-free survival rates were higher in patients with non-NA cessation than in those with NAs cessation (78.3 % vs. 62.1 %, P < 0.001; 62.8 % vs. 44.7 %, P < 0.001). The need for liver transplantation was significantly higher in the NA cessation group compared with the non-NAs cessation group (21.2 % vs. 7.0 %, P < 0.001). The Kaplan-Meier curve showed that inappropriate NA therapy discontinuation had reduced 28- and 90-day live transplant-free survival compared with other precipitating events prior to PSM (all P < 0.001). After matching, the 28- and 90-day transplantation-free survival was also significantly lower in the NA cessation group vs. the non-NA cessation group (P = 0.012 and P = 0.022). In conclusion, the inappropriate cessation of NA therapy is associated with reduced liver transplant-free survival in patients with HBV-related ACLF.

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

Nucleos(t)ide analogues (NAs) are the main drug category used in chronic hepatitis B (CHB) treatment. Despite the fact that NAs have a favourable safety profile, undesired adverse events (AEs) may occur during the treatment of CHB. Given the eminent number of patients currently receiving NAs, even a small risk of any of these toxicities can represent a major medical issue. The main objective of this review was to analyse information available on AEs associated with the use of NAs in published studies. We choose the following MesH terms for this systematic review: chronic hepatitis B, side effects and treatment. All articles published from 1 January 1990 up to 19 February 2018 in MEDLINE of PubMed, EMBASE, the Cochrane Library and LILACS databases were searched. A total of 120 articles were selected for analysis, comprising 6419 patients treated with lamivudine (LAM), 5947 with entecavir (ETV), 3566 with tenofovir disoproxil fumarate (TDF), 3096 with telbivudine (LdT), 1178 with adefovir dipivoxil (ADV) and 876 with tenofovir alafenamide (TAF). The most common AEs in all NAs assessed were abdominal pain/discomfort, nasopharyngitis/upper respiratory tract infections, fatigue, and headache. TAF displays the highest density of AEs per patient treated among NAs (1.14 AE/treated patient). In conclusion, treatment of CHB with NAs is safe, with a low incidence of AEs. Despite the general understanding TAF being safer than TDF, the number of patients treated with TAF still is too small in comparison to other NAs to consolidate an accurate safety profile. PROSPERO Registration No. CRD42018086471.

Hepatitis B-related glomerulonephritis and optimization of treatment.

Introduction: Multiple studies have revealed a strong relationship between the development of nephropathy and hepatitis B virus (HBV) infection. The underlying pathogenesis of hepatitis B-related glomerulonephritis (HBV-GN) involves immune complexes, which can be isolated from kidney tissues. Clearance of HBV antigenemia improves renal impairment and proteinuria in HBV-GN patients.Areas covered: In this review, we present our current understanding of the epidemiology, pathogenesis, pathology, diagnosis, and treatment of HBV-GN. We discuss the advantages and disadvantages of oral nucleoside/nucleotide analogs (NAs), and the main pharmaceutical treatment for hepatis B.Expert opinion: Currently, antiviral agents are the main HBV-GN therapeutic agents. Although no randomized controlled clinical trials have compared the efficacy of interferon (IFN) and NA, we suggest IFN treatment for pediatric patients (IFN-α in patients ≥1 year; pegIFN-α in patients ≥3 years) considering treatment duration and absence of resistance. Novel NAs have brought about promising treatment options involving high efficacy viral suppression and low resistance rates. NAs with a high barrier to resistance (e.g. entecavir) are recommended as first-line therapy of HBV-GN. Immunosuppression monotherapy, such as corticosteroids, is of little benefit and potentially harmful to HBV-GN patients due to the possibility of viral reactivation.

A case of entecavir-induced Fanconi syndrome.

Acquired Fanconi syndrome has been associated with the long-term ingestion of several nucleoside analogs used to treat chronic hepatitis B virus infection. However, the nucleoside analog entecavir has not been found to cause nephrotoxicity. We report a case of entecavir-induced Fanconi syndrome. Our patient was a 73-year-old man admitted to our hospital because of renal dysfunction. He also presented with hyperaminoaciduria, renal diabetes, phosphaturia, hypophosphatemia, hypokalemia, hypouricemia, and hyperchloremic metabolic acidosis, supporting a diagnosis of Fanconi syndrome. In this case, the cause of Fanconi syndrome was most likely entecavir, which had been administered as needed depending on his renal function for 5 years. After drug discontinuation and replacement with tenofovir alafenamide fumarate therapy once a week, the patient's kidney function recovered and electrolyte anomalies partially improved. We highlight the fact that entecavir may induce severe renal dysfunction, which can cause the development of Fanconi syndrome; therefore, close monitoring of proximal tubular function is recommended during entecavir therapy.

Efficacy and safety of the nucleoside analog GS-441524 for treatment of cats with naturally occurring feline infectious peritonitis.

OBJECTIVES: The aim of this study was to determine the safety and efficacy of the nucleoside analog GS-441524 for cats suffering from various forms of naturally acquired feline infectious peritonitis (FIP). METHODS: Cats ranged from 3.4-73 months of age (mean 13.6 months); 26 had effusive or dry-to-effusive FIP and five had non-effusive disease. Cats with severe neurological and ocular FIP were not recruited. The group was started on GS-441524 at a dosage of 2.0 mg/kg SC q24h for at least 12 weeks and increased when indicated to 4.0 mg/kg SC q24h. RESULTS: Four of the 31 cats that presented with severe disease died or were euthanized within 2-5 days and a fifth cat after 26 days. The 26 remaining cats completed the planned 12 weeks or more of treatment. Eighteen of these 26 cats remain healthy at the time of publication (OnlineFirst, February 2019) after one round of treatment, while eight others suffered disease relapses within 3-84 days. Six of the relapses were non-neurological and two neurological. Three of the eight relapsing cats were treated again at the same dosage, while five cats had the dosage increased from 2.0 to 4.0 mg/kg q24h. The five cats treated a second time at the higher dosage, including one with neurological disease, responded well and also remain healthy at the time of publication. However, one of the three cats re-treated at the original lower dosage relapsed with neurological disease and was euthanized, while the two remaining cats responded favorably but relapsed a second time. These two cats were successfully treated a third time at the higher dosage, producing 25 long-time survivors. One of the 25 successfully treated cats was subsequently euthanized due to presumably unrelated heart disease, while 24 remain healthy. CONCLUSIONS AND RELEVANCE: GS-441524 was shown to be a safe and effective treatment for FIP. The optimum dosage was found to be 4.0 mg/kg SC q24h for at least 12 weeks.

CMCdG, a Novel Nucleoside Analog with Favorable Safety Features, Exerts Potent Activity against Wild-Type and Entecavir-Resistant Hepatitis B Virus.

We designed, synthesized, and characterized a novel nucleoside analog, (1S,3S,5S)-3-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-5-hydroxy-1-(hydroxymethyl)-2-methylene-cyclopentanecarbonitrile, or 4'-cyano-methylenecarbocyclic-2'-deoxyguanosine (CMCdG), and evaluated its anti-hepatitis B virus (anti-HBV) activity, safety, and related features. CMCdG's in vitro activity was determined using quantitative PCR and Southern blotting assays, and its cytotoxicity was determined with a 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay, while its in vivo activity and safety were determined in human liver-chimeric mice infected with wild-type HBV genotype Ce (HBVWTCe) and an entecavir (ETV)-resistant HBV variant containing the amino acid substitutions L180M, S202G, and M204V (HBVETV-RL180M/S202G/M204V). CMCdG potently inhibited HBV production in HepG2.2.15 cells (50% inhibitory concentration [IC50], ∼30 nM) and HBVWTCe plasmid-transfected Huh7 cells (IC50, 206 nM) and efficiently suppressed ETV-resistant HBVETV-RL180M/S202G/M204V (IC50, 2,657 nM), while it showed no or little cytotoxicity (50% cytotoxic concentration, >500 µM in most hepatocytic cells examined). Two-week peroral administration of CMCdG (1 mg/kg of body weight/day once a day [q.d.]) to HBVWTCe-infected human liver-chimeric mice reduced the level of viremia by ∼2 logs. CMCdG also reduced the level of HBVETV-RL180M/S202G/M204V viremia by ∼1 log in HBVETV-RL180M/S202G/M204V-infected human liver-chimeric mice, while ETV (1 mg/kg/day q.d.) completely failed to reduce the viremia. None of the CMCdG-treated mice had significant drug-related changes in body weights or serum human albumin levels. Structural analyses using homology modeling, semiempirical quantum methods, and molecular dynamics revealed that although ETV triphosphate (TP) forms good van der Waals contacts with L180 and M204 of HBVWTCe reverse transcriptase (RT), its contacts with the M180 substitution are totally lost in the HBVETV-RL180M/S202G/M204V RT complex. However, CMCdG-TP retains good contacts with both the HBVWTCe RT and HBVETV-RL180M/S202G/M204V RT complexes. The present data warrant further studies toward the development of CMCdG as a potential therapeutic for patients infected with drug-resistant HBV and shed light on the further development of more potent and safer anti-HBV agents.

High percentage atypical hepatocellular carcinoma in chronic hepatitis B patients treated with nucleos(t)ide analogs.

Nucleos(t)ide analogs are used for preventing liver cirrhosis in chronic hepatitis B patients, but the risk factors of hepatocellular carcinoma (HCC) in these patients remain unclear. We designed this retrospective cohort study, the aim is to determine the risk factors for HCC development and its image presentation under nucleos(t)ide analogs treatment.In this study, patients were treated with lamivudine (LAM), entecavir 0.5 mg (ETV), or telbivudine (LdT), and followed-up for at least 2 years to detect HCC and its presentation. Assessment of the risk factors for HCC included age, sex, HBeAg, viral load, liver cirrhosis, current and previous medications, and liver function tests.Totally, 396 patients were recruited, and 18 patients developed HCC. The mean time from the treatment to HCC development was 28.5 ±â€Š16.7 months. The clinical characteristics in HCC and no-HCC groups showed significant differences among age (52.8 ±â€Š6.1 vs 47.1 ±â€Š12.6 years, P <.01), baseline alanine transaminase (ALT) levels (161.4 ±â€Š177.3 vs 361.7 ±â€Š496.3, P <.01), and baseline liver cirrhosis (72.2% vs 29.9%, P <.01). In patients aged ≥45 years, the hazard ratio of HCC was 10.2 and liver cirrhosis was 4.1. Majority of HCCs developed in the right liver (14/18), were single numbered (13/18), had tumor size about 1.9 ±â€Š0.7 cm, were classified as T1 (14/18, TNM staging), and the atypical image occupied 88% of the HCC cases.The patients aged ≧45 years on long-term nucleos(t)ide analog therapy, and with baseline liver cirrhosis were at a high risk of HCC. Regular alpha-fetoprotein (AFP) assessment and image study of these patients are the gold standards for early HCC detection in patients with high percentage atypical HCC appearances.

[Mechanism relevant to hepatocellular carcinoma occurrence after negative conversion of viral DNA in treatment of chronic hepatitis B patients with nucleos(t)ide drugs].

Hepatocellular carcinoma (HCC) is a common malignant tumor in China, and most of the patients have a background of chronic HBV infection. Nucleos(t)ide drugs (NAs) are currently recommended by major guidelines as a first-line treatments for chronic hepatitis B. However, it is still clinically possible to observe that some patients who have acquired virological response (HBV DNA below the lower detection limit) after NAS treatment progress to HCC, and its mechanism of development is still unclear. In this review, the mechanism relevant to HCC progression in treatment of chronic hepatitis B patients with NAs is analyzed mainly from the aspects of gene integration and persistent inflammatory injury.

Hepatitis B surface antigen loss after discontinuing nucleos(t)ide analogue for treatment of chronic hepatitis B patients is persistent in White patients.

OBJECTIVE: The objective of this study was to determine the long-term clinical outcome and persistence of hepatitis B surface antigen (HBsAg) loss after discontinuation of treatment. BACKGROUND: The prognosis of patients with chronic hepatitis B (CHB) treated with nucleos(t)ide analogues (NAs) who discontinue treatment after loss of HBsAg remains largely unknown, particularly in White patients. PATIENTS AND METHODS: We analysed a cohort of patients with CHB who discontinued NA treatment after loss of HBsAg. A total of 69 patients with hepatitis-B-e antigen-positive or hepatitis-B-e antigen-negative CHB with undetectable HBsAg during NA treatment were included after discontinuation of treatment, and followed up for a median period of 37.8 months (interquartile range: 23.8-54.6 months). RESULTS: At the end of follow-up, none of the patients showed spontaneous reappearance of HBsAg and only one patient had detectable hepatitis B virus DNA (22 IU/ml). Another patient negative for HBsAg and anti-HBs developed hepatitis B virus reactivation without elevated transaminases after treatment with corticosteroids and vincristine for dendritic cell neoplasm, 38 months after withdrawal of the antiviral treatment. Regarding clinical outcome, a patient with cirrhosis developed hepatocellular carcinoma, 6.6 years after discontinuing treatment. None of the patients had hepatic decompensation or underwent liver transplantation. CONCLUSION: HBsAg clearance after discontinuing NAs in patients with CHB is persistent and associated with good prognosis. The risk for developing hepatocellular carcinoma persists among patients with cirrhosis.

A Dynamic Model for Predicting Outcome in Patients with HBV Related Acute-On-Chronic Liver Failure.

INTRODUCTION AND AIM: Accurately predicting the prognosis of individual patient is crucial in the management of ACLF. We aimed to establish a specific prognostic model for HBV-related ACLF patients treated with nucleoside analog (NA). MATERIAL AND METHODS: We prospectively collected 205 ACLF cases diagnosed according to the APASL criteria. A dynamic prognostic model based on APASL criteria was established and validated. To demonstrate that the model is also applicable to those within EASL criteria, we divided the patients into two groups: met APASL criteria only (group A, n = 123); met both APASL and EASL criteria (group B, n = 82). Its prognostic accuracy was also compared with chronic liver failure-sequential organ failure assessment (CLIF-SOFA) score in group B. RESULTS: The model is: R = 0.94 x Bilirubin + 0.53 x evolution of Bilirubin - 0.45 x PT-A - 0.22 x evolution in PT-A -0.1 x PLT + 10 x anti-HBe. The area under receiver operating characteristic curve (AUC) of the model for predicting 90-day mortality was 0.86, which was significantly higher than that of model for end stage liver disease(MELD), MELD-Na, CLIF-SOFA, ΔMELD (7d) and ΔMELD-Na (7d), ΔCLIF- SOFA(7d) (all p < 0.01). The AUC of our model in the validation group was 0.79 which was superior to MELD (0.45) CLIF-SOFA (0.53) score in group B patients (p < 0.01). CONCLUSION: In conclusion, the model was superior to the conventional methods in predicting the outcomes of patients with HBV related ACLF treated with NA. It is the first description of a novel prognostic model using consecutive data in patients with HBV-induced acute-on-chronic liver failure (ACLF) treated by nucleoside analogs.

[Chronic hepatitis B and D (delta) : Current and future treatments]. / Chronische Hepatitis B und D (delta) : Gegenwärtige und zukünftige Therapien.

BACKGROUND: Worldwide, hepatitis B virus (HBV) infection is among the 30 leading causes of death, despite effective vaccination and therapeutic options. Chronic hepatitis delta (coinfection with hepatitis D virus) leads to a rapid disease progression. AIMS: Based on current international guidelines and studies, an overview about present and future therapeutic options for chronic hepatitis B and delta is provided. RESULTS: Therapy with nucleoside or nucleotide analogues leads to nearly complete HBV DNA suppression, which is associated with regression of liver fibrosis and a lower risk for the development of hepatocellular carcinoma. Therapy of chronic hepatitis delta with pegylated interferon alfa achieves only low response rates with high risk for virological relapse. Various therapeutic approaches are currently being investigated in preclinical and clinical studies and have led to a significant reduction of hepatitis B surface antigen (HBsAg) and HDV RNA. CONCLUSION: Current therapies of chronic HBV infection can effectively reduce subsequent complications. New therapeutic approaches promise functional cure (HBsAg loss) of HBV infection and effective treatment options for patients with chronic hepatitis delta.