Biosynthesis of phosphonic and phosphinic acid natural products.

Natural products containing carbon-phosphorus bonds (phosphonic and phosphinic acids) have found widespread use in medicine and agriculture. Recent years have seen a renewed interest in the biochemistry and biology of these compounds with the cloning of the biosynthetic gene clusters for several family members. This review discusses the commonalities and differences in the molecular logic that lie behind the biosynthesis of these compounds. The current knowledge regarding the metabolic pathways and enzymes involved in the production of a number of natural products, including the approved antibiotic fosfomycin, the widely used herbicide phosphinothricin (PT), and the clinical candidate for treatment of malaria FR-900098, is presented. Many of the enzymes involved in the biosynthesis of these compounds catalyze chemically and biologically unprecedented transformations, and a wealth of new biochemistry has been revealed through their study. These investigations have also suggested new strategies for natural product discovery.

Global HIV Incidence Analysis and Implications for Affordability Using Long-Acting Cabotegravir Versus Continuous and Event-Driven Oral Preexposure Prophylaxis.

BACKGROUND: The HIV Prevention Trials Network (HPTN) 083/084 trials showed up to 88% increased efficacy of long-acting cabotegravir (CAB-LA) versus continuous oral tenofovir disoproxil fumarate/emtricitabine (TDF/FTC). However, CAB-LA's high price limits the number of people who can be treated within fixed prevention budgets. Global human immunodeficiency virus (HIV) prevention budgets are highly limited, with TDF/FTC widely available as a low-cost generic. In randomized clinical trials, event-driven TDF/FTC has shown similar preventive efficacy to continuous TDF/FTC. METHODS: A systematic review of global HIV incidence studies was conducted. Weighted incidence was calculated in each at-risk population. HIV infection rates were evaluated for 5 prevention strategies, with additional HIV testing, education, and service access costs assumed for each ($18 per person per year). Assumed efficacies were 90% (continuous CAB-LA), 60% (continuous TDF/FTC), and 60% (event-driven TDF/FTC). Using weighted incidence and an assumed 100 000 target population, annual HIV infection rates by population were calculated for each prevention strategy. RESULTS: Ninety-eight studies in 5 230 189 individuals were included. Incidence per 100 person-years ranged from 0.03 (blood donors) to 3.82 (people who inject drugs). Using the number needed to treat to benefit for each strategy, a mean incidence of 2.6 per 100 person-years in at-risk populations, and a 100 000 target population, current-price continuous CAB-LA cost $949 487 per HIV infection successfully prevented, followed by target-price CAB-LA ($11 453), continuous TDF/FTC ($4231), and event-driven TDF/FTC ($1923). CONCLUSIONS: High prices of CAB-LA limit numbers treatable within fixed budgets. Low-cost event-driven TDF/FTC consistently prevents the most HIV infections within fixed budgets.

NPP-669, a prodrug of cidofovir, is highly efficacious against human adenovirus infection in the permissive Syrian hamster model.

Human adenoviruses can cause serious, disseminated infections in immunocompromised patients. For pediatric allogeneic stem cell transplant patients, the case fatality rate can reach 80%. Still, there is no available antiviral drug that is specifically approved by the Food and Drug Administration for the treatment of adenovirus infections. To fill this pressing medical need, we have developed NPP-669, a prodrug of cidofovir with broad activity against double-stranded DNA viruses, including adenoviruses. Here, we report on the in vivo anti-adenoviral efficacy of NPP-669. Using the immunosuppressed Syrian hamster as the model, we show that NPP-669 is highly efficacious when dosed orally at 1 mg/kg and 3 mg/kg. In a delayed administration experiment, NPP-669 was more effective than brincidofovir, a similar compound that reached Phase III clinical trials. Furthermore, parenteral administration of NPP-669 increased its efficacy approximately 10-fold compared to oral dosing without apparent toxicity, suggesting that this route may be preferable in a hospital setting. Based on these findings, we believe that NPP-669 is a promising new compound that needs to be further investigated.

Cidofovir for Viral Infections in Immunocompromised Children: Guidance on Dosing, Safety, Efficacy, and a Review of the Literature.

OBJECTIVE: To describe the use of cidofovir (CDV) for viral infections in immunocompromised children (IC) and provide guidance on dosing and supportive care. DATA SOURCES: A PubMed search was conducted for literature published between 1997 and January 2022 using the following terms: cidofovir, plus children or pediatrics. STUDY SELECTION AND DATA EXTRACTION: Limits were set to include human subjects less than 24 years of age receiving intravenous (IV) or intrabladder CDV for treatment of infections due to adenovirus, polyomavirus-BK (BKV), herpesviruses, or cytomegalovirus. DATA SYNTHESIS: Data were heterogeneous, with largely uncontrolled studies. Conventional dosing (CDV 5 mg/kg/dose weekly) was commonly used in 60% (31/52) of studies and modified dosing (CDV 1 mg/kg/dose 3 times/week) was used in 17% (9/52) of studies, despite being off-label. Nephrotoxicity reported across studies totaled 16% (65/403 patients), which was higher for conventional dosing 29 of 196 patients (15%) than modified dosing 1 of 27 patients (4%). Saline hyperhydration and concomitant probenecid remain the cornerstones of supportive care, while some regimens omitting probenecid are emerging to target BKV. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: To our knowledge, this is the first comprehensive review of CDV use (indications, dosing, supportive care, response, and nephrotoxicity) in pediatric IC. CONCLUSIONS: Effective utilization of CDV in IC remains challenging. Further prospective studies are needed to determine the optimal CDV dosing; however, less aggressive dosing regimens such as modified thrice weekly dosing or low dosing once weekly omitting probenecid to enhance urinary penetration may be reasonable alternatives to conventional dosing in some IC.

Treatment and Vaccination for Smallpox and Monkeypox.

The smallpox infection with the variola virus was one of the most fatal disorders until a global eradication was initiated in the twentieth century. The last cases were reported in Somalia 1977 and as a laboratory infection in the UK 1978; in 1980, the World Health Organization (WHO) declared smallpox for extinct. The smallpox virus with its very high transmissibility and mortality is still a major biothreat, because the vaccination against smallpox was stopped globally in the 1980s. For this reason, new antivirals (cidofovir, brincidofovir, and tecovirimat) and new vaccines (ACAM2000, LC16m8 and Modified Vaccine Ankara MVA) were developed. For passive immunization, vaccinia immune globulin intravenous (VIGIV) is available. Due to the relationships between orthopox viruses such as vaccinia, variola, mpox (monkeypox), cowpox, and horsepox, the vaccines (LC16m8 and MVA) and antivirals (brincidofovir and tecovirimat) could also be used in the mpox outbreak with positive preliminary data. As mutations can result in drug resistance against cidofovir or tecovirimat, there is need for further research. Further antivirals (NIOCH-14 and ST-357) and vaccines (VACΔ6 and TNX-801) are being developed in Russia and the USA. In conclusion, further research for treatment and prevention of orthopox infections is needed and is already in progress. After a brief introduction, this chapter presents the smallpox and mpox disease and thereafter full overviews on antiviral treatment and vaccination including the passive immunization with vaccinia immunoglobulins.

Assessment of immunomodulation and regulation of cell cycle in epithelium and stroma after Cidofovir injection in patients with recurrent respiratory papillomatosis-Pilot study.

Recurrent respiratory papillomatosis is strictly connected with human papillomavirus (HPV) infection of the epithelium of the upper respiratory tract. The main treatment of lesions located in the larynx or lower pharynx includes microsurgical excision by using a CO2 laser. To decrease the amount of surgical procedures gain in importance combined therapy with antiviral agents. The aim of this study was to investigate the effect of the intralesional application of Cidofovir on the tissue of laryngeal papillomas. We have shown that simultaneous microsurgery with adjuvant therapy of Cidofovir reduces chronic inflammation (by measuring the expression of CD4 and CD8 in tissue samples), cell proliferation, and regulates the cell cycle of HPV-infected cells by reducing the expression of p53 and p63 proteins. In addition, this strategy reduces the multiple surgical procedures and regrowth of the pathology.

Resistant herpes simplex virus infections - who, when, and what's new?

PURPOSE OF REVIEW: This review summarizes the literature on acyclovir resistant herpes infections and the most recent data pertinent to diagnosis and treatment in the immunocompromised patient population. RECENT FINDINGS: Although fairly rare, acyclovir resistant herpes infections can be challenging to diagnose. Clinicians should be aware of this entity when facing refractory herpes infections. With updated diagnostics, the diagnosis is usually made through viral culture and sequencing. Therapeutic choices depend on the extent of disease. Topical therapy may be appropriate for mucocutaneous disease. Intravenous antiviral therapies such as foscarnet and cidofovir may be necessary for disseminated, ophthalmologic, central nervous system, or visceral disease. Experimental therapies such as pritelivir are in clinical trials. SUMMARY: Immunosuppressed patients are at risk for developing acyclovir-resistant herpes, which can be challenging to diagnose and treat, although emerging therapeutic options look promising.

Besifovir therapy improves hepatic histology and reduces covalently closed circular DNA in chronic hepatitis B patients.

BACKGROUND AND AIM: Besifovir dipivoxil maleate (BSV) was reported to have comparable antiviral efficacy and superior renal and bone safety to tenofovir disoproxil fumarate (TDF) in chronic hepatitis B (CHB) patients. The present study aims to evaluate changes of liver histology and intrahepatic covalently closed circular DNA (cccDNA) levels by BSV treatment in comparison with TDF therapy. METHODS: This is a subset study of the phase 3 trial comparing BSV with TDF. Among them, only CHB patients willing to participate in a histologic evaluation study were enrolled. Liver histologic examination and intrahepatic cccDNA quantification were performed. RESULTS: A total of 46 CHB patients received liver biopsies (BSV, n = 29; TDF, n = 17). After 48 weeks of treatment, virological response rate was comparable between the groups (P = 0.707). Follow-up liver biopsies showed that necroinflammation was significantly improved in the both groups. However, the histological response rate defined as the proportion of subjects whose modified histologic activity index score decreased by ≥ 2 without deterioration in fibrosis was higher in the BSV group than in the TDF group (77.8% vs 36.4%, P = 0.048). The proportion of subjects with Ishak fibrosis score 3 or more decreased from 77.7% to 55.5% in the BSV and that decreased from 72.7% to 45.4% in the TDF group. The intrahepatic cccDNA significantly decreased from baseline after 48 weeks of BSV or TDF treatment (P < 0.001) without intergroup differences (P = 0.349). CONCLUSIONS: The BSV therapy improves hepatic histology and decreases intrahepatic cccDNA in CHB patients.

The potency of selatogrel, a reversible antagonist of the P2Y12 receptor, is affected by calcium concentration.

Here, we report the in vitro characterization of the P2Y12 receptor antagonist selatogrel (ACT-246475). Binding studies with radiolabeled selatogrel demonstrated that selatogrel is a competitive antagonist of ADP binding to the P2Y12 receptor with a fast onset of action. Consequently, selatogrel was confirmed to be a potent inhibitor of P2Y12-mediated intra-platelet signaling and ADP-induced platelet activation. Characterization of selatogrel in platelet-rich plasma in vitro demonstrated that the mode of anti-coagulation affected the anti-platelet potency. Specifically, in platelet-rich plasma containing physiological calcium concentration (anticoagulated with a direct thrombin inhibitor), selatogrel achieved half-maximal inhibition of ADP-induced platelet aggregation at a 3-fold lower concentration than in conditions with low calcium concentration (anticoagulated with citrate). Furthermore, calcium-dependent reduction in selatogrel potency was observed in whole blood platelet aggregation using the VerifyNow™ system with a 3.7-fold potency loss in low calcium conditions. A comparable potency loss was also observed with the reversible P2Y12 receptor antagonists ticagrelor, cangrelor and elinogrel. Furthermore, receptor-binding experiments using radiolabeled selatogrel confirmed a 3-fold lowering of selatogrel binding affinity to the P2Y12 receptor in low calcium conditions. In conclusion, our data suggest that in low calcium conditions (i.e., citrate-anticoagulated blood), there is a risk of underestimating the potency of reversible P2Y12 receptor antagonists. To avoid overdosing, and a potential increase in bleeding risk, we propose that the ex vivo evaluation of reversible P2Y12 receptor antagonists should be performed with platelet assay systems containing physiological calcium concentration.

Investigation of the Anticancer Effect of α-Aminophosphonates and Arylidine Derivatives of 3-Acetyl-1-aminoquinolin-2(1H)-one on the DMBA Model of Breast Cancer in Albino Rats with In Silico Prediction of Their Thymidylate Synthase Inhibitory Effect.

Breast cancer is a major cause of death in women worldwide. In this study, 60 female rats were classified into 6 groups; negative control, α-aminophosphonates, arylidine derivatives of 3-acetyl-1-aminoquinolin-2(1H)-one, DMBA, DMBA & α-aminophosphonates, and DMBA & arylidine derivatives of 3-acetyl-1-aminoquinolin-2(1H)-one. New α-aminophosphonates and arylidine derivatives of 3-acetyl-1-aminoquinolin-2(1H)-one were synthesized and elucidated by different spectroscopic and elemental analysis. Histopathological examination showed marked proliferation of cancer cells in the DMBA group. Treatment with α-aminophosphonates mainly decreased tumor mass. Bcl2 expression increased in DMBA-administered rats and then declined in the treated groups, mostly with α-aminophosphonates. The level of CA15-3 markedly declined in DMBA groups treated with α-aminophosphonates and arylidine derivatives of 3-acetyl-1-aminoquinolin-2(1H)-one. Gene expression of GST-P, PCNA, PDK, and PIK3CA decreased in the DMBA group treated with α-aminophosphonates and arylidine derivatives of 3-acetyl-1-aminoquinolin-2(1H)-one, whereas PIK3R1 and BAX increased in the DMBA group treated with α-aminophosphonates and arylidine derivatives of 3-acetyl-1-aminoquinolin-2(1H)-one. The molecular docking postulated that the investigated compounds can inhibt the Thymidylate synthase TM due to high hydrophobicity charachter.

Modified Taohong Siwu decoction improves cardiac function after myocardial ischaemia and reperfusion in rats by promoting endogenous stem cell mobilization and regulating metabolites.

CONTEXT: Taohong Siwu decoction (THSWD) has been shown to promote heart repair in myocardial infarction. OBJECTIVE: To determine the effects of modified THSWD (THSWD plus four ingredients) on myocardial ischaemia and reperfusion (I/R) injury. MATERIALS AND METHODS: Sixty Sprague-Dawley rats were randomly divided into the I/R group and three different modified THSWD dose groups (gavage administration, 1.215, 2.43, and 4.86 g, respectively). 2,3,5-Triphenyltetrazolium chloride and Evans blue staining were used to detect the infarct area at 24 h after treatment. The serum biochemical indexes and cell apoptosis were examined to determine myocardial injury. The number of endogenous stem cells, expression of stromal dell derived factor-1 (SDF-1) and stem cell factor (SCF), and cardiac function were measured at 4 weeks. The serum was collected for metabolomic analysis. RESULTS: The high-dose modified THSWD group presented a reduced infarction area (decreased by 21.3%), decreased levels of lactate dehydrogenase and creatinine kinase, attenuated cell apoptosis, and enhanced superoxide dismutase activity in early stage I/R compared with other groups. The serum SCF and SDF-1 levels were higher in the high-dose group than in the I/R group. At 4 weeks, the infarct size and collagen content were the lowest, and the ejection fraction and fractional shortening values were the highest in the high-dose group. Moreover, high-dose modified THSWD affected the metabolism of phosphonate and phosphonate, taurine, and hypotaurine. CONCLUSIONS: Endogenous stem cell mobilization and metabolic regulation were related to the cardioprotection of modified THSWD. We provided a new strategy and direction for the treatment of cardiovascular diseases with traditional Chinese medicine.

Immunomodulatory Mechanism of Acyclic Nucleoside Phosphates in Treatment of Hepatitis B Virus Infection.

BACKGROUND AND AIMS: Current treatment with nucleos(t)ide analogs (NUCs) safely controls the replication of hepatitis B virus (HBV) and improves prognosis in patients with HBV. However, the inability to completely clear HBV is problematic, and novel therapies are desired. It has been believed that all NUCs have similar functions to inhibit HBV reverse transcriptase. However, our recent findings that only acyclic nucleoside phosphonates (ANPs; adefovir dipivoxil and tenofovir disoproxil fumarate) had an additional effect of inducing interferon (IFN)-λ3 in the gastrointestinal tract suggests that ANPs are not only distinct from nucleoside analogs (lamivudine and entecavir) in their structures but also in their functions. Because enteric lipopolysaccharide (LPS) can cross the intestine and affect peripheral blood mononuclear cells (PBMCs), we hypothesized that orally administered ANPs could have further additional effects to modulate LPS-mediated cytokine profile in PBMCs. APPROACH AND RESULTS: This study showed that pretreatment of PBMCs, from either healthy volunteers or patients with HBV, with ANPs inhibited LPS-mediated interleukin (IL)-10 production, which reciprocally induced IL-12p70 and tumor necrosis factor-α production in a dose-dependent manner. Furthermore, the combination of IFN-α and ANPs synergistically enhanced LPS-mediated IL-12p70 production in PBMCs. Mechanistic analyses revealed that cellular metabolites of ANPs directly bound the Akt protein, inhibiting its translocation to the plasma membrane, thereby impairing Akt phosphorylation. Therefore, pretreatment of PBMCs with ANPs impairs LPS-mediated IL-10 production. CONCLUSIONS: Among NUCs, only ANPs have an additional pharmacological effect modulating LPS-mediated cytokine production, which is expected to produce favorable immune responses toward HBV elimination. This additional immunomodulation by ANPs in PBMCs, as well as IFN-λ3 induction in the gastrointestinal tract, provides insights into HBV treatment.

Besifovir Dipivoxil Maleate 144-Week Treatment of Chronic Hepatitis B: An Open-Label Extensional Study of a Phase 3 Trial.

INTRODUCTION: Chronic hepatitis B (CHB) remains a major worldwide public health concern. Besifovir dipivoxil maleate (BSV) is a new promising treatment for CHB. However, long-term efficacy and safety have not yet been evaluated. Therefore, the goal of the study is to determine the antiviral efficacy and safety of BSV treatment over a 144-week duration (BSV-BSV) in comparison with those of a sequential treatment with tenofovir disoproxil fumarate (TDF) followed by a 96-week duration BSV administration (TDF-BSV). METHODS: After 48 weeks of a double-blind comparison between BSV and TDF treatments, patients continued the open-label BSV study. We evaluated antiviral efficacy and drug safety up to 144 weeks for BSV-BSV and TDF-BSV groups. The primary endpoint was a virological response (hepatitis B virus DNA < 69 IU/mL). RESULTS: Among the 197 patients enrolled, 170 and 158 patients entered the second-year and third-year open-label phase extensional study, respectively, whereas 153 patients completed the 144-week follow-up. The virological response rate over the 144-week period was 87.7% and 92.1% in BSV-BSV and TDF-BSV groups, respectively (P = 0.36). The rates of ALT normalization and HBeAg seroconversion were similar between the groups. No drug-resistant mutations to BSV were noted. Bone mineral density and renal function were well preserved in the BSV-BSV group and were significantly improved after switching therapy in TDF-BSV patients. DISCUSSION: This extensional study of a phase 3 trial (NCT01937806) suggests that BSV treatment is efficacious and safe for long-term use in treatment-naïve and TDF-experienced patients with CHB.

An antiviral drug-resistant mutant of hepatitis B virus with high replication capacity in association with a large in-frame deletion in the preS1 region of viral surface gene.

We amplified a full-length hepatitis B virus (HBV) genome from the serum of a chronic hepatitis B patient who experienced virological breakthrough with high HBV DNA titer following adefovir (ADV) therapy. The PCR product was cloned and sequencing of the six clones revealed an isolate of C2 subgenotype. Mutation(s) in the polymerase gene responsible for ADV resistance included rtA181T (all clones) and rtN236T (four clones). The rtA181T mutation caused the W172* nonsense mutation in the overlapping S gene. In addition, all the clones harbored another nonsense mutation in the S gene (C69*) and a 207nt in-frame deletion in the preS1 region. These clones were converted to a 1.1mer construct for transient transfection of Huh7 cells. All the clones were deficient in hepatitis B surface antigen production. Three clones had similar levels of DNA replication. Comparison with a wild-type clone of the same genotype revealed a higher intracellular level of replicative DNA for clone c4, which was reduced by putting back the deleted 207nt, but not by co-transfection with an expression construct for the three surface proteins to rescue virion production. The HBcAg expression of the c4 and c4+207nt clones was mainly in the nucleus. Co-transfection with the L/M/S proteins expression construct did not alter the distribution of core. Clone c4 showed a significantly decreased susceptibility to ADV, a mild reduction in susceptibility to lamivudine and tenofovir, but remained sensitive to entecavir. In conclusion, this is an unusual ADV-resistant HBV isolate harboring two nonsense mutations in the S gene and a large in-frame deletion in the preS1 region, but still retains a high replication phenotype, which can provide a platform for recombinant vector construction.

Brincidofovir for the treatment of human adenovirus infection in pediatric solid organ transplant recipients: A case series.

HAdV viremia can cause significant morbidity among pediatric recipients of SOT with variability in incidence and severity of disease based on the type of allograft. Currently, there are no US FDA-approved treatments for HAdV infections, and historically, the mainstay of treatment has been decreasing immunosuppression, with antiviral therapies reserved for those with severe disease. We describe the treatment of four pediatric SOT recipients (two kidney, one combined kidney-liver, and one liver) presenting with HAdV disease at our institution using brincidofovir. Our case series highlights the variability in presentation and the potential for severe disease in pediatric SOT recipients as we review disease presentation, disease course, complications, and treatment with brincidofovir.

48 weeks outcome after cessation of nucleos(t)ide analogue therapy in chronic hepatitis B patients.

INTRODUCTION AND OBJECTIVE: The aim of the present study was to investigate the significance of serum HBsAg levels in treatment cessation of nucleoside analogues (NAs) in patients with chronic hepatitis B (CHB) infection. METHODS: In 158 CHB patients with long-term NAs treatment, 74 patients were in HBeAg negative and had a HBsAg level <1500IU/mL, 36 of whom were informed and consented to cease NAs. HBsAg, HBV DNA and liver function were examined in the 1st, 3rd, 6th, 9th and 12th month after treatment cessation. RESULTS: The sustained response rate was 88.89% (32/36) within one year after NAs cessation. Sub-group analysis was based on HBsAg levels of patients with NAs cessation, there was no relapse case in 11 patients whose HBsAg <50IU/mL, and the negative predictive value (NPV) was 100%. Seroconversion of HBsAg occurred in 3 patients. 2 patients from 21 cases whose HBsAg was between 50IU/mL and 1000IU/mL relapsed. 2 of 4 patients whose in HBsAg >1000IU/mL relapsed. HBsAg of patients with a sustained response decreased slowly. In contrast, HBsAg levels increased gradually in relapsed patients, and the increase of HBsAg was precedent to relapses of HBV DNA and ALT. Multivariate analysis suggested that only HBsAg level showed a close correlation with HBV DNA relapses. ROC curve analysis suggested that the increase of HBsAg level in the 3rd and 6th month after NAs cessation had a great predictive value for relapses. CONCLUSION: Monitoring of base line HBsAg level can predict outcomes of NAs cessation in HBeAg-negative chronic hepatitis B. HBsAg <50IU/mL has higher predictive values of better sustained responses in HBeAg-negative CHB patients.

Influence of Besifovir Dipivoxil Maleate Combined with L-Carnitine on Hepatic Steatosis in Patients with Chronic Hepatitis B.

BACKGROUND: Besifovir dipivoxil maleate (BSV) with L-carnitine is the first-line antiviral agent for chronic hepatitis B (CHB) infection. We investigated whether BSV combined with L-carnitine improves hepatic steatosis (HS). METHODS: Treatment-naïve patients with CHB who were initiated on antiviral therapy (AVT) were enrolled. The magnitude of HS was assessed using hepatic steatosis index (HSI), and HS improvement was defined as a ≥ 10% reduction in the HSI score from the baseline. RESULTS: The mean age of the study patients was 56 years with a male predominance (n = 178, 64.7%). The mean body mass index (BMI), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and platelet count were 23.5 kg/m², 49.6 IU/L, 49.0 IU/L, and 191.3 × 109/L, respectively. The mean HSI and fibrosis (FIB)-4 index were 32.6 and 0.5, respectively. After 6 months of AVT, platelet count (mean, 191.3→167.0 × 109/L), fasting glucose (mean, 113.1→105.9 mg/dL), AST (mean, 49.6→28.0 IU/L), ALT (mean, 49.0→33.9 IU/L), and total cholesterol (mean, 170.0→162.1 mg/dL) levels significantly decreased (all P < 0.05). In the BSV group, AST (mean, 95.2→30.2 IU/L) and ALT (mean, 81.1→31.1 IU/L) levels significantly reduced (all P < 0.05), whereas HSI and FIB-4 index were maintained (all P > 0.05). In the univariate analysis, age, BMI, diabetes, cirrhosis, fasting glucose level, and ALT were significantly associated with HS improvement (all P < 0.05). CONCLUSION: BSV with L-carnitine did not show any improvement of HS in patients with CHB. Further prospective randomized controlled studies are needed to validate the potential beneficial effects of BSV with L-carnitine in CHB infection.

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

BACKGROUND & AIMS: Besifovir dipivoxil maleate (BSV) has activity against hepatitis B virus (HBV). We performed a phase 3 study to compare the antiviral efficacy and safety of BSV vs tenofovir disoproxil fumarate (TDF) in patients with chronic HBV infection in Korea. METHODS: We conducted a double-blind, non-inferiority trial of 197 patients with chronic HBV infection at 22 sites in South Korea, from November 2013 through February 2016. Patients were randomly assigned to groups given BSV (150 mg, n = 99) or TDF (300 mg, n = 98) for 48 weeks. We evaluated virologic responses to therapy (HBV DNA <69 IU/mL or 400 copies/ml), bone mineral density (BMD), and renal outcomes for safety analysis. The main efficacy endpoint was the proportion of patients with a virologic response at week 48. After 48 weeks, TDF was switched to BSV (150 mg) for an additional 48 weeks. RESULTS: After 48 weeks of treatment, 80.9% of patients given BSV and 84.9% of patients given TDF met the efficacy endpoint, indicating the non-inferiority of BSV to TDF. At week 96, 87.2% of patients in the BSV-BSV and 85.7% of patients in the TDF-BSV had a virologic response. At week 48, changes in hip and spine BMD differed significantly between the BSV and TDF groups, whereas the estimated glomerular filtration rate in the TDF group was significantly lower than that in the BSV group. However, at 96 weeks, there were no significant differences in BMD and estimated glomerular filtration rate between the BSV-BSV and TDF-BSV groups. CONCLUSIONS: BSV has antiviral efficacy comparable to that of TDF after 48 weeks of treatment, with durable effects for 96 weeks. BSV has a better safety profile than TDF, in terms of bone and renal outcomes. ClinicalTrials.gov no: NCT01937806.

Serum hepatitis B virus RNA levels as a predictor of HBeAg seroconversion during treatment with peginterferon alfa-2a.

BACKGROUND: Hepatitis B e antigen (HBeAg) seroconversion represents an endpoint of treatment of chronic hepatitis B virus (HBV) infections. METHODS: We have studied whether levels of serum hepatitis B virus ribonucleic acid (HBV RNA) during pegylated interferon alfa-2a treatment might be helpful for predicting HBeAg seroconversion. 61 HBeAg-positive chronic hepatitis B (CHB) patients treated with pegylated interferon alfa-2a alone or in combination with adefovir (10 mg/day) for 48 weeks were included in this retrospective analysis. Response was defined as HBeAg seroconversion at 24 weeks posttreatment. Receiver operating characteristic analyses were used to identify baseline and on-treatment HBV RNA levels associated with response. RESULTS: Twenty-two of 61 (36.1%) patients achieved a response. Baseline HBV RNA levels were lower in responders than in nonresponders (4.55 ± 1.19 and 5.90 ± 1.13 copies/mL, respectively, P = 0.001). Baseline HBV RNA cut off level (200,000 copies/mL) provided a positive predictive value (PPV) of 56.0% and a negative predictive value (NPV) of 77.8%. HBV RNA level (3000 copies/mL) at week 12 provide a PPV of 75.0% and a NPV of 82.8%. Moreover, HBeAg seroconversion rates at 24 weeks posttreatment were significantly higher in patients with HBV RNA ≤ 200,000 copies/mL at baseline and HBV RNA ≤ 3000 copies/mL at week 12 (92.9%) versus others (12.5%) (All P < 0.05). CONCLUSIONS: In Conclusions, serum HBV RNA levels may serve as a novel tool for prediction of HBeAg seroconversion during therapy with pegylated interferon alfa-2a in HBeAg-positive CHB patients.

Predicting HBsAg clearance in genotype A chronic hepatitis B using HBsAg epitope profiling: A biomarker for functional cure.

BACKGROUND AND AIM: Functional cure is the major goal of chronic hepatitis B (CHB) therapy though few biomarkers predict this outcome. HBsAg epitope occupancy can be influenced by therapeutic and immune pressure. The aim of this study was to map the HBsAg epitope profiles during long-term nucleos(t)ide analogue therapy in patients with genotype A CHB, in the context of HBsAg loss (SL)/seroconversion. METHODS: We evaluated 25 genotype A CHB patients in the GS-US-174-0103 trial of HBeAg-positive CHB patients treated with tenofovir or adefovir for 4 years, 14 who achieved SL whilst 11 had no change. We epitope mapped the major domains of HBsAg to identify those patients with HBsAg clearance profile (CP) (loss of binding at both loops 1 and 2 epitopes of the 'a' determinant) vs non-clearance profile (no change in epitope recognition, or loss of epitope binding at one loop only), correlating this to on-treatment HBsAg responses. Complexed anti-HBs was also measured. RESULTS: Analysis of the HBsAg epitope profiles of the 25 patients at baseline identified no predictive correlation with SL. In contrast, analysis at week 48 and end of study (week 192) or prior to SL identified significant predictive associations between development of HBsAg CPs and outcome of functional cure. The detection of a CP also correlated with the development of an alanine aminotransferase flare and detection of anti-HBs complexed with HBsAg. CONCLUSION: The detection of HBsAg CPs by epitope mapping represents a novel viral biomarker, reflecting an emerging anti-HBs selection pressure prior to functional cure.