Bulevirtide Combined with Pegylated Interferon for Chronic Hepatitis D.

BACKGROUND: In a phase 3 trial, bulevirtide monotherapy led to a virologic response in patients with chronic hepatitis D. Pegylated interferon (peginterferon) alfa-2a is recommended by guidelines as an off-label treatment for this disease. The role of combination therapy with bulevirtide and peginterferon alfa-2a, particularly with regard to finite treatment, is unclear. METHODS: In this phase 2b, open-label trial, we randomly assigned patients to receive peginterferon alfa-2a alone (180 µg per week) for 48 weeks; bulevirtide at a daily dose of 2 mg or 10 mg plus peginterferon alfa-2a (180 µg per week) for 48 weeks, followed by the same daily dose of bulevirtide for 48 weeks; or bulevirtide at a daily dose of 10 mg alone for 96 weeks. All the patients were followed for 48 weeks after the end of treatment. The primary end point was an undetectable level of hepatitis D virus (HDV) RNA at 24 weeks after the end of treatment. The primary comparison was between the 10-mg bulevirtide plus peginterferon alfa-2a group and the 10-mg bulevirtide monotherapy group. RESULTS: A total of 24 patients received peginterferon alfa-2a alone, 50 received 2 mg and 50 received 10 mg of bulevirtide plus peginterferon alfa-2a, and 50 received 10 mg of bulevirtide monotherapy. At 24 weeks after the end of treatment, HDV RNA was undetectable in 17% of the patients in the peginterferon alfa-2a group, in 32% of those in the 2-mg bulevirtide plus peginterferon alfa-2a group, in 46% of those in the 10-mg bulevirtide plus peginterferon alfa-2a group, and in 12% of those in the 10-mg bulevirtide group. For the primary comparison, the between-group difference was 34 percentage points (95% confidence interval, 15 to 50; P<0.001). At 48 weeks after the end of treatment, HDV RNA was undetectable in 25% of the patients in the peginterferon alfa-2a group, in 26% of those in the 2-mg bulevirtide plus peginterferon alfa-2a group, in 46% of those in the 10-mg bulevirtide plus peginterferon alfa-2a group, and in 12% of those in the 10-mg bulevirtide group. The most frequent adverse events were leukopenia, neutropenia, and thrombocytopenia. The majority of adverse events were of grade 1 or 2 in severity. CONCLUSIONS: The combination of 10-mg bulevirtide plus peginterferon alfa-2a was superior to bulevirtide monotherapy with regard to an undetectable HDV RNA level at 24 weeks after the end of treatment. (Funded by Gilead Sciences; MYR 204 ClinicalTrials.gov number, NCT03852433.).

A Phase 3, Randomized Trial of Bulevirtide in Chronic Hepatitis D.

BACKGROUND: Coinfection with hepatitis D virus (HDV) accelerates the progression of liver disease associated with chronic hepatitis B. Bulevirtide inhibits the entry of HDV into hepatocytes. METHODS: In this ongoing phase 3 trial, patients with chronic hepatitis D, with or without compensated cirrhosis, were randomly assigned, in a 1:1:1 ratio, to receive bulevirtide subcutaneously at 2 mg per day (2-mg group) or 10 mg per day (10-mg group) for 144 weeks or to receive no treatment for 48 weeks followed by bulevirtide subcutaneously at 10 mg per day for 96 weeks (control group). Patients will complete 96 weeks of additional follow-up after the end of treatment. The primary end point was a combined response at week 48 of an undetectable HDV RNA level, or a level that decreased by at least 2 log10 IU per milliliter from baseline, and normalization of the alanine aminotransferase (ALT) level. The key secondary end point was an undetectable HDV RNA level at week 48, in a comparison between the 2-mg group and the 10-mg group. RESULTS: A total of 49 patients were assigned to the 2-mg group, 50 to the 10-mg group, and 51 to the control group. A primary end-point response occurred in 45% of patients in the 2-mg group, 48% in the 10-mg group, and 2% in the control group (P<0.001 for the comparison of each dose group with the control group). The HDV RNA level at week 48 was undetectable in 12% of patients in the 2-mg group and in 20% in the 10-mg group (P = 0.41). The ALT level normalized in 12% of patients in the control group, 51% in the 2-mg group (difference from control, 39 percentage points [95% confidence interval {CI}, 20 to 56]), and 56% in the 10-mg group (difference from control, 44 percentage points [95% CI, 26 to 60]). Loss of hepatitis B virus surface antigen (HBsAg) or an HBsAg level that decreased by at least 1 log10 IU per milliliter did not occur in the bulevirtide groups by week 48. Headache, pruritus, fatigue, eosinophilia, injection-site reactions, upper abdominal pain, arthralgia, and asthenia were more common in the 2-mg and 10-mg groups combined than in the control group. No treatment-related serious adverse events occurred. Dose-dependent increases in bile acid levels were noted in the 2-mg and 10-mg groups. CONCLUSIONS: After 48 weeks of bulevirtide treatment, HDV RNA and ALT levels were reduced in patients with chronic hepatitis D. (Funded by Gilead Sciences; MYR 301 ClinicalTrials.gov number, NCT03852719.).

The menace of severe adverse events and deaths associated with viral gene therapy and its potential solution.

Over the past decade, in vivo gene replacement therapy has significantly advanced, resulting in market approval of numerous therapeutics predominantly relying on adeno-associated viral vectors (AAV). While viral vectors have undeniably addressed several critical healthcare challenges, their clinical application has unveiled a range of limitations and safety concerns. This review highlights the emerging challenges in the field of gene therapy. At first, we discuss both the role of biological barriers in viral gene therapy with a focus on AAVs, and review current landscape of in vivo human gene therapy. We delineate advantages and disadvantages of AAVs as gene delivery vehicles, mostly from the safety perspective (hepatotoxicity, cardiotoxicity, neurotoxicity, inflammatory responses etc.), and outline the mechanisms of adverse events in response to AAV. Contribution of every aspect of AAV vectors (genomic structure, capsid proteins) and host responses to injected AAV is considered and substantiated by basic, translational and clinical studies. The updated evaluation of recent AAV clinical trials and current medical experience clearly shows the risks of AAVs that sometimes overshadow the hopes for curing a hereditary disease. At last, a set of established and new molecular and nanotechnology tools and approaches are provided as potential solutions for mitigating or eliminating side effects. The increasing number of severe adverse reactions and, sadly deaths, demands decisive actions to resolve the issue of immune responses and extremely high doses of viral vectors used for gene therapy. In response to these challenges, various strategies are under development, including approaches aimed at augmenting characteristics of viral vectors and others focused on creating secure and efficacious non-viral vectors. This comprehensive review offers an overarching perspective on the present state of gene therapy utilizing both viral and non-viral vectors.

Patient-reported outcomes in chronic hepatitis delta: An exploratory analysis of the Phase III MYR301 trial of bulevirtide.

BACKGROUND & AIMS: Once-daily treatment of chronic hepatitis delta (CHD) with bulevirtide is well tolerated and associated with significant reductions in HDV RNA in the blood and in biochemical liver disease activity. This study explored the effects of 48-week bulevirtide treatment on health-related quality of life (HRQoL) in patients with CHD. METHODS: In an open-label, randomised, Phase 3 trial, 150 patients with CHD and compensated liver disease were stratified by liver cirrhosis status and randomised 1:1:1 to no treatment (control), bulevirtide 2 mg/day, or bulevirtide 10 mg/day for 48 weeks. HRQoL was evaluated by the following patient-reported outcome (PRO) instruments at baseline, 24 weeks, and 48 weeks: EQ-5D-3L, Hepatitis Quality of Life Questionnaire (HQLQ), and Fatigue Severity Scale (FSS). RESULTS: Patient characteristics and HRQoL scores were balanced at baseline between the treatment (2 mg, n = 49; 10 mg, n = 50) and control (n = 51) groups. Patients receiving 2-mg bulevirtide reported significant improvements compared with controls on the HQLQ domains of role physical, hepatitis-specific limitations, and hepatitis-specific health distress. Numerically higher scores for general health, hepatitis-specific limitations, and hepatitis-specific health distress domains were reported by patients with cirrhosis who received bulevirtide vs control. FSS scores remained stable across treatment groups throughout. At week 48, patients in the 2-mg group showed greater mean improvement from baseline in health status compared with controls on the EQ-5D-3L visual analogue scale. CONCLUSION: PROs indicate that 48-week treatment with bulevirtide monotherapy may improve aspects of HRQoL in patients with CHD. IMPACT AND IMPLICATIONS: Bulevirtide 2 mg is the only approved treatment for patients with chronic hepatitis delta (CHD) in the EU. Patients with CHD have worse quality of life scores than those with chronic hepatitis B. Bulevirtide treatment for 48 weeks reduced HDV RNA and alanine aminotransferase levels and was well tolerated among patients with CHD. For the first time, this study shows that patients who received bulevirtide therapy for 48 weeks reported improvements in physical and hepatitis-related quality of life domains compared to those who did not receive therapy (control group). CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier, NCT03852719.

Bulevirtide monotherapy in patients with chronic HDV: Efficacy and safety results through week 96 from a phase III randomized trial.

BACKGROUND & AIMS: Bulevirtide (BLV), a first-in-class entry inhibitor, is approved in Europe for the treatment of chronic hepatitis delta (CHD). BLV monotherapy was superior to delayed treatment at week (W) 48, the primary efficacy endpoint, in the MYR301 study (NCT03852719). Here, we assessed if continued BLV therapy until W96 would improve virologic and biochemical response rates, particularly among patients who did not achieve virologic response at W24. METHODS: In this ongoing, open-label, randomized phase III study, patients with CHD (N = 150) were randomized (1:1:1) to treatment with BLV 2 mg/day (n = 49) or 10 mg/day (n = 50), each for 144 weeks, or to delayed treatment for 48 weeks followed by BLV 10 mg/day for 96 weeks (n = 51). Combined response was defined as undetectable hepatitis delta virus (HDV) RNA or a decrease in HDV RNA by ≥2 log10 IU/ml from baseline and alanine aminotransferase (ALT) normalization. Other endpoints included virologic response, ALT normalization, and change in HDV RNA. RESULTS: Of 150 patients, 143 (95%) completed 96 weeks of the study. Efficacy responses were maintained and/or improved between W48 and W96, with similar combined, virologic, and biochemical response rates between BLV 2 and 10 mg. Of the patients with a suboptimal early virologic response at W24, 43% of non-responders and 82% of partial responders achieved virologic response at W96. Biochemical improvement often occurred independently of virologic response. Adverse events were mostly mild, with no serious adverse events related to BLV. CONCLUSIONS: Virologic and biochemical responses were maintained and/or increased with longer term BLV therapy, including in those with suboptimal early virologic response. BLV monotherapy for CHD was safe and well tolerated through W96. IMPACT AND IMPLICATIONS: In July 2023, bulevirtide was fully approved for the treatment of chronic hepatitis delta (CHD) in Europe based on clinical study results from up to 48 weeks of treatment. Understanding the efficacy and safety of bulevirtide over the longer term is important for healthcare providers. In this analysis, we demonstrate that bulevirtide monotherapy for 96 weeks in patients with CHD was associated with continued improvements in combined, virologic, and biochemical responses as well as liver stiffness from week 48 at both the 2 mg and 10 mg doses. Patients with suboptimal virologic responses to bulevirtide at week 24 also benefited from continued therapy, with the majority achieving virologic response or biochemical improvement by week 96. GOV IDENTIFIER: NCT03852719.

Saponin is Essential for the Isolation of Proteins and RNA from Biological Nanoparticles.

Extracellular vesicles (EVs), biomimetics, and other biological nanoparticles (BNs) produced from human cells are gaining increasing attention in the fields of molecular diagnostics and nanomedicine for the delivery of therapeutic cargo. In particular, BNs are considered prospective delivery vehicles for different biologics, including protein and RNA therapeutics. Moreover, EVs are widely used in molecular diagnostics for early detection of disease-associated proteins and RNA. Technical approaches for measuring biologics mostly originated from the field of EVs and were later adopted for other BNs, such as extracellular vesicle-mimetic nanovesicles, membrane nanoparticles (nanoghosts), and hybrid nanoparticles, with minimal modifications. Here, we demonstrate that BNs are highly resistant to protocols that severely underestimate the protein and RNA content of BNs, and provide the relevance of these data both for general BNs characterization and practical applications of CRISPR/Cas-based therapies. We demonstrate that the addition of saponin leads to an ∼2- to 7-fold enhancement in protein isolation and an ∼2- to 242-fold improvement in RNA recovery rates and detection efficiency. Differences in the proteolipid contents of BNs, measured by Raman and surface-enhanced Raman spectroscopy, correlate with their susceptibility to saponin treatment for cargo extraction. Finally, we develop a unified protocol using saponin to efficiently isolate proteins and RNA from the BNs. These data demonstrate that previously utilized protocols underestimate BN cargo contents and offer gold standard protocols that can be broadly adopted into the field of nanobiologics, molecular diagnostics, and analytical chemistry.

Basic Guide for Approaching Drug Delivery with Extracellular Vesicles.

Extracellular vesicles (EVs) are natural carriers of biomolecules that play a crucial role in cell-to-cell communication and tissue homeostasis under normal and pathological conditions, including inflammatory diseases and cancer. Since the discovery of the pro-regenerative and immune-modulating properties of EVs, EV-based therapeutics have entered clinical trials for conditions such as myocardial infarction and autoimmune diseases, among others. Due to their unique advantages-such as superior bioavailability, substantial packaging capacity, and the ability to traverse biological barriers-EVs are regarded as a promising platform for targeted drug delivery. However, achieving a sufficient accumulation of therapeutic agents at the target site necessitates a larger quantity of EVs per dose compared to using EVs as standalone drugs. This challenge can be addressed by administering larger doses of EVs, increasing the drug dosage per administration, or enhancing the selective accumulation of EVs at target cells. In this review, we will discuss methods to improve the isolation and purification of EVs, approaches to enhance cargo packaging-including proteins, RNAs, and small-molecule drugs-and technologies for displaying targeting ligands on the surface of EVs to facilitate improved targeting. Ultimately, this guide can be applied to the development of novel classes of EV-based therapeutics and to overcoming existing technological challenges.

Biomimetic approaches for targeting tumor-promoting inflammation.

With the ultimate goal of increasing tumor accumulation of therapeutics, various nanocarriers have been designed to overcome biological barriers encountered at each stage, from drug administration to the cancerous lesion. Stabilizing circulation and functionalization of the targeting surface impart high tumor accumulation properties to nanocarriers. However, various cells can recognize and infiltrate the tumor microenvironment more efficiently than synthetic carriers via overexpression of adhesive ligands, particularly in inflamed stroma of tumors. Thus, a new field of nanomedicine, called biomimicry, has evolved to generate nanoparticles with the same biological characteristics as cells that naturally infiltrate tumors. Revolutionary synthetic processes have been developed to transfer the cell membrane of leukocytes and mesenchymal cells to synthetic carriers. In addition, cells can generate their own "nanocarriers," known as exosomes, to transport molecular messages to distant sites, while biomimicry of viral and bacterial agents allows high targeting efficiency towards inflammatory immune cells. Alterations in the protein expression in cancer cells caused by inflammation can also be exploited for drug delivery. Finally, new developments in biomimetic drug delivery focus on turning the infiltrating cells into microcarriers that can actively perfuse the tumor and eventually release their therapeutic payload. In this review, we summarize recent developments in biomimetic drug delivery with a particular focus on targeting the tumor inflammatory microenvironment.

CRISPR-Cas systems for diagnosing infectious diseases.

Infectious diseases are a global health problem affecting billions of people. Developing rapid and sensitive diagnostic tools is key for successful patient management and curbing disease spread. Currently available diagnostics are very specific and sensitive but time-consuming and require expensive laboratory settings and well-trained personnel; thus, they are not available in resource-limited areas, for the purposes of large-scale screenings and in case of outbreaks and epidemics. Developing new, rapid, and affordable point-of-care diagnostic assays is urgently needed. This review focuses on CRISPR-based technologies and their perspectives to become platforms for point-of-care nucleic acid detection methods and as deployable diagnostic platforms that could help to identify and curb outbreaks and emerging epidemics. We describe the mechanisms and function of different classes and types of CRISPR-Cas systems, including pros and cons for developing molecular diagnostic tests and applications of each type to detect a wide range of infectious agents. Many Cas proteins (Cas3, Cas9, Cas12, Cas13, Cas14 etc.) have been leveraged to create highly accurate and sensitive diagnostic tools combined with technologies of signal amplification and fluorescent, potentiometric, colorimetric, lateral flow assay detection and other. In particular, the most advanced platforms -- SHERLOCK/v2, DETECTR, CARMEN or CRISPR-Chip -- enable detection of attomolar amounts of pathogenic nucleic acids with specificity comparable to that of PCR but with minimal technical settings. Further developing CRISPR-based diagnostic tools promises to dramatically transform molecular diagnostics, making them easily affordable and accessible virtually anywhere in the world. The burden of socially significant diseases, frequent outbreaks, recent epidemics (MERS, SARS and the ongoing COVID-19) and outbreaks of zoonotic viruses (African Swine Fever Virus etc.) urgently need the developing and distribution of express-diagnostic tools. Recently devised CRISPR-technologies represent the unprecedented opportunity to reshape epidemiological surveillance and molecular diagnostics.

Nanomedicine for increasing the oral bioavailability of cancer treatments.

Oral administration is an appealing route of delivering cancer treatments. However, the gastrointestinal tract is characterized by specific and efficient physical, chemical, and biological barriers that decrease the bioavailability of medications, including chemotherapeutics. In recent decades, the fields of material science and nanomedicine have generated several delivery platforms with high potential for overcoming multiple barriers associated to oral administration. This review describes the properties of several nanodelivery systems that improve the bioavailability of orally administered therapeutics, highlighting their advantages and disadvantages in generating successful anticancer oral nanomedicines.

Glecaprevir/pibrentasvir for 8 weeks in treatment-naïve patients with chronic HCV genotypes 1-6 and compensated cirrhosis: The EXPEDITION-8 trial.

BACKGROUND & AIMS: Eight-week glecaprevir/pibrentasvir leads to high rates of sustained virological response at post-treatment week 12 (SVR12) across HCV genotypes (GT) 1-6 in treatment-naïve patients without cirrhosis. We evaluated glecaprevir/pibrentasvir once daily for 8 weeks in treatment-naïve patients with compensated cirrhosis. METHODS: EXPEDITION-8 was a single-arm, multicenter, phase IIIb trial. The primary and key secondary efficacy analyses were to compare the lower bound of the 95% CI of the SVR12 rate in i) patients with GT1,2,4-6 in the per protocol (PP) population, ii) patients with GT1,2,4-6 in the intention-to-treat (ITT) population, iii) patients with GT1-6 in the PP population, and iv) patients with GT1-6 in the ITT population, to pre-defined efficacy thresholds based on historical SVR12 rates for 12 weeks of glecaprevir/pibrentasvir in the same populations. Safety was also assessed. RESULTS: A total of 343 patients were enrolled. Most patients were male (63%), white (83%), and had GT1 (67%). The SVR12 rate in patients with GT1-6 was 99.7% (n/N = 334/335; 95%CI 98.3-99.9) in the PP population and 97.7% (n/N = 335/343; 95% CI 96.1-99.3) in the ITT population. All primary and key secondary efficacy analyses were achieved. One patient (GT3a) experienced relapse (0.3%) at post-treatment week 4. Common adverse events (≥5%) were fatigue (9%), pruritus (8%), headache (8%), and nausea (6%). Serious adverse events (none related) occurred in 2% of patients. No adverse event led to study drug discontinuation. Clinically significant laboratory abnormalities were infrequent. CONCLUSIONS: Eight-week glecaprevir/pibrentasvir was well tolerated and led to a similarly high SVR12 rate as the 12-week regimen in treatment-naïve patients with chronic HCV GT1-6 infection and compensated cirrhosis. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03089944. LAY SUMMARY: This study was the first to evaluate an 8-week direct-acting antiviral (DAA) regimen active against all major types of hepatitis C virus (HCV) in untreated patients with compensated cirrhosis. High virological cure rates were achieved with glecaprevir/pibrentasvir across HCV genotypes 1-6, and these high cure rates did not depend on any patient or viral characteristics present before treatment. This may simplify care and allow non-specialist healthcare professionals to treat these patients, contributing to global efforts to eliminate HCV.

Orthologous CRISPR/Cas9 systems for specific and efficient degradation of covalently closed circular DNA of hepatitis B virus.

Covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV) is the major cause of viral persistence and chronic hepatitis B. CRISPR/Cas9 nucleases can specifically target HBV cccDNA for decay, but off-target effects of nucleases in the human genome limit their clinical utility. CRISPR/Cas9 systems from four different species were co-expressed in cell lines with guide RNAs targeting conserved regions of the HBV genome. CRISPR/Cas9 systems from Streptococcus pyogenes (Sp) and Streptococcus thermophilus (St) targeting conserved regions of the HBV genome blocked HBV replication and, most importantly, resulted in degradation of over 90% of HBV cccDNA by 6 days post-transfection. Degradation of HBV cccDNA was impaired by inhibition of non-homologous end-joining pathway and resulted in an erroneous repair of HBV cccDNA. HBV cccDNA methylation also affected antiviral activity of CRISPR/Cas9. Single-nucleotide HBV genetic variants did not impact anti-HBV activity of St CRISPR/Cas9, suggesting its utility in targeting many HBV variants. However, two or more mismatches impaired or blocked CRISPR/Cas9 activity, indicating that host DNA will not likely be targeted. Deep sequencing revealed that Sp CRISPR/Cas9 induced off-target mutagenesis, whereas St CRISPR/Cas9 had no effect on the host genome. St CRISPR/Cas9 system represents the safest system with high anti-HBV activity.

Gene Editing by Extracellular Vesicles.

CRISPR/Cas technologies have advanced dramatically in recent years. Many different systems with new properties have been characterized and a plethora of hybrid CRISPR/Cas systems able to modify the epigenome, regulate transcription, and correct mutations in DNA and RNA have been devised. However, practical application of CRISPR/Cas systems is severely limited by the lack of effective delivery tools. In this review, recent advances in developing vehicles for the delivery of CRISPR/Cas in the form of ribonucleoprotein complexes are outlined. Most importantly, we emphasize the use of extracellular vesicles (EVs) for CRISPR/Cas delivery and describe their unique properties: biocompatibility, safety, capacity for rational design, and ability to cross biological barriers. Available molecular tools that enable loading of desired protein and/or RNA cargo into the vesicles in a controllable manner and shape the surface of EVs for targeted delivery into specific tissues (e.g., using targeting ligands, peptides, or nanobodies) are discussed. Opportunities for both endogenous (intracellular production of CRISPR/Cas) and exogenous (post-production) loading of EVs are presented.

Clearing of Foreign Episomal DNA from Human Cells by CRISPRa-Mediated Activation of Cytidine Deaminases.

Restriction of foreign DNA is a fundamental defense mechanism required for maintaining genomic stability and proper function of mammalian cells. APOBEC cytidine deaminases are crucial effector molecules involved in clearing pathogenic DNA of viruses and other microorganisms and improperly localized self-DNA (DNA leakages). Mastering the expression of APOBEC provides the crucial means both for developing novel therapeutic approaches for combating infectious and non-infectious diseases and for numerous research purposes. In this study, we report successful application of a CRISPRa approach to effectively and specifically overexpress APOBEC3A and APOBEC3B deaminases and describe their effects on episomal and integrated foreign DNA. This method increased target gene transcription by >6-50-fold in HEK293T cells. Furthermore, CRISPRa-mediated activation of APOBEC3A/APOBEC3B suppressed episomal but not integrated foreign DNA. Episomal GC-rich DNA was rapidly destabilized and destroyed by CRISPRa-induced APOBEC3A/APOBEC3B, while the remaining DNA templates harbored frequent deaminated nucleotides. To conclude, the CRISPRa approach could be readily utilized for manipulating innate immunity and investigating the effects of the key effector molecules on foreign nucleic acids.

Dead Cas Systems: Types, Principles, and Applications.

The gene editing tool CRISPR-Cas has become the foundation for developing numerous molecular systems used in research and, increasingly, in medical practice. In particular, Cas proteins devoid of nucleolytic activity (dead Cas proteins; dCas) can be used to deliver functional cargo to programmed sites in the genome. In this review, we describe current CRISPR systems used for developing different dCas-based molecular approaches and summarize their most significant applications. We conclude with comments on the state-of-art in the CRISPR field and future directions.

Summary of available surveillance data on hepatitis C virus infection from eight Arctic countries, 2012 to 2014.

We summarised available hepatitis C virus (HCV) surveillance data for 2012-14 from Arctic/sub-Arctic countries/regions. We sent a HCV data collection template by email to public health authorities in all jurisdictions. Population statistics obtained from census sources for each country were used to estimate rates of reported acute and chronic/undifferentiated HCV cases. Seven countries with Arctic regions (Canada, Denmark, Finland, Greenland, Norway, Sweden and the United States, represented by the state of Alaska), including three Canadian territories and one province, as well as 11 Russian subnational Arctic regions, completed the data collection template. Data on acute HCV infection during 2014 was available from three Arctic countries and all Russian Arctic regions (rate range 0/100,000 population in Greenland, as well as Nenets and Chukotka Automous Okrugs (Russian subnational Arctic regions) to 3.7/100,000 in the Russian Republic of Komi). The rate of people with chronic/undifferentiated HCV infection in 2014 ranged from 0/100,000 in Greenland to 171.2/100,000 in Alaska. In most countries/regions, the majority of HCV-infected people were male and aged 19-64 years. Differences in surveillance methods preclude direct comparisons of HCV surveillance data between Arctic countries/regions. Our data can inform future efforts to develop standardised approaches to HCV surveillance in the Arctic countries/regions by identifying similarities/differences between the surveillance data collected.

ABT-450/r-ombitasvir and dasabuvir with or without ribavirin for HCV.

BACKGROUND: The interferon-free regimen of ABT-450 with ritonavir (ABT-450/r), ombitasvir, and dasabuvir with or without ribavirin has shown efficacy in inducing a sustained virologic response in a phase 2 study involving patients with hepatitis C virus (HCV) genotype 1 infection. We conducted two phase 3 trials to examine the efficacy and safety of this regimen in previously untreated patients with HCV genotype 1 infection and no cirrhosis. METHODS: We randomly assigned 419 patients with HCV genotype 1b infection (PEARL-III study) and 305 patients with genotype 1a infection (PEARL-IV study) to 12 weeks of ABT-450/r-ombitasvir (at a once-daily dose of 150 mg of ABT-450, 100 mg of ritonavir, and 25 mg of ombitasvir), dasabuvir (250 mg twice daily), and ribavirin administered according to body weight or to matching placebo for ribavirin. The primary efficacy end point was a sustained virologic response (an HCV RNA level of <25 IU per milliliter) 12 weeks after the end of treatment. RESULTS: The study regimen resulted in high rates of sustained virologic response among patients with HCV genotype 1b infection (99.5% with ribavirin and 99.0% without ribavirin) and among those with genotype 1a infection (97.0% and 90.2%, respectively). Of patients with genotype 1b infection, 1 had virologic failure, and 2 did not have data available at post-treatment week 12. Among patients with genotype 1a infection, the rate of virologic failure was higher in the ribavirin-free group than in the ribavirin group (7.8% vs. 2.0%). In both studies, decreases in the hemoglobin level were significantly more common in patients receiving ribavirin. Two patients (0.3%) discontinued the study drugs owing to adverse events. The most common adverse events were fatigue, headache, and nausea. CONCLUSIONS: Twelve weeks of treatment with ABT-450/r-ombitasvir and dasabuvir without ribavirin was associated with high rates of sustained virologic response among previously untreated patients with HCV genotype 1 infection. Rates of virologic failure were higher without ribavirin than with ribavirin among patients with genotype 1a infection but not among those with genotype 1b infection. (Funded by AbbVie; PEARL-III and PEARL-IV ClinicalTrials.gov numbers, NCT01767116 and NCT01833533.).

Biomimetic Nanoparticles for Basic Drug Delivery.

Biomimetic nanoparticles (BMNPs) are innovative nanovehicles that replicate the properties of naturally occurring extracellular vesicles, facilitating highly efficient drug delivery across biological barriers to target organs and tissues while ensuring maximal biocompatibility and minimal-to-no toxicity. BMNPs can be utilized for the delivery of therapeutic payloads and for imparting novel properties to other nanotechnologies based on organic and inorganic materials. The application of specifically modified biological membranes for coating organic and inorganic nanoparticles has the potential to enhance their therapeutic efficacy and biocompatibility, presenting a promising pathway for the advancement of drug delivery technologies. This manuscript is grounded in the fundamentals of biomimetic technologies, offering a comprehensive overview and analytical perspective on the preparation and functionalization of BMNPs, which include cell membrane-coated nanoparticles (CMCNPs), artificial cell-derived vesicles (ACDVs), and fully synthetic vesicles (fSVs). This review examines both "top-down" and "bottom-up" approaches for nanoparticle preparation, with a particular focus on techniques such as cell membrane coating, cargo loading, and microfluidic fabrication. Additionally, it addresses the technological challenges and potential solutions associated with the large-scale production and clinical application of BMNPs and related technologies.

m6A Methylation in Regulation of Antiviral Innate Immunity.

The epitranscriptomic modification m6A is a prevalent RNA modification that plays a crucial role in the regulation of various aspects of RNA metabolism. It has been found to be involved in a wide range of physiological processes and disease states. Of particular interest is the role of m6A machinery and modifications in viral infections, serving as an evolutionary marker for distinguishing between self and non-self entities. In this review article, we present a comprehensive overview of the epitranscriptomic modification m6A and its implications for the interplay between viruses and their host, focusing on immune responses and viral replication. We outline future research directions that highlight the role of m6A in viral nucleic acid recognition, initiation of antiviral immune responses, and modulation of antiviral signaling pathways. Additionally, we discuss the potential of m6A as a prognostic biomarker and a target for therapeutic interventions in viral infections.

Swelling, Rupture and Endosomal Escape of Biological Nanoparticles Per Se and Those Fused with Liposomes in Acidic Environment.

Biological nanoparticles (NPs), such as extracellular vesicles (EVs), exosome-mimetic nanovesicles (EMNVs) and nanoghosts (NGs), are perspective non-viral delivery vehicles for all types of therapeutic cargo. Biological NPs are renowned for their exceptional biocompatibility and safety, alongside their ease of functionalization, but a significant challenge arises when attempting to load therapeutic payloads, such as nucleic acids (NAs). One effective strategy involves fusing biological NPs with liposomes loaded with NAs, resulting in hybrid carriers that offer the benefits of both biological NPs and the capacity for high cargo loads. Despite their unique parameters, one of the major issues of virtually any nanoformulation is the ability to escape degradation in the compartment of endosomes and lysosomes which determines the overall efficiency of nanotherapeutics. In this study, we fabricated all major types of biological and hybrid NPs and studied their response to the acidic environment observed in the endolysosomal compartment. In this study, we show that EMNVs display increased protonation and swelling relative to EVs and NGs in an acidic environment. Furthermore, the hybrid NPs exhibit an even greater response compared to EMNVs. Short-term incubation of EMNVs in acidic pH corresponding to late endosomes and lysosomes again induces protonation and swelling, whereas hybrid NPs are ruptured, resulting in the decline in their quantities. Our findings demonstrate that in an acidic environment, there is enhanced rupture and release of vesicular cargo observed in hybrid EMNVs that are fused with liposomes compared to EMNVs alone. This was confirmed through PAGE electrophoresis analysis of mCherry protein loaded into nanoparticles. In vitro analysis of NPs colocalization with lysosomes in HepG2 cells demonstrated that EMNVs mostly avoid the endolysosomal compartment, whereas hybrid NPs escape it over time. To conclude, (1) hybrid biological NPs fused with liposomes appear more efficient in the endolysosomal escape via the mechanism of proton sponge-associated scavenging of protons by NPs, influx of counterions and water, and rupture of endo/lysosomes, but (2) EMNVs are much more efficient than hybrid NPs in actually avoiding the endolysosomal compartment in human cells. These results reveal biochemical differences across four major types of biological and hybrid NPs and indicate that EMNVs are more efficient in escaping or avoiding the endolysosomal compartment.