Search Results (545)

The global elimination of hepatitis C virus (HCV) has been prioritized by the World Health Organization (WHO) as a key public health target, with a deadline set for 2030. This initiative aims to significantly reduce both new infection rates and HCV-associated mortality. A major breakthrough in achieving this goal has been the development of direct-acting antiviral agents (DAAs), which offer cure rates exceeding 95%, along with excellent safety and tolerability. Nevertheless, transmission via parenteral routes continues to be the dominant pathway, particularly among high-risk groups, such as individuals who inject drugs, incarcerated populations, those exposed to unsafe medical practices, and healthcare professionals. Identifying, monitoring, and delivering tailored interventions to these groups is crucial to interrupt ongoing transmission and to reduce the burden of chronic liver disease. On a global scale, several nations have demonstrated measurable progress toward HCV elimination, with some nearing the targets set by WHO. These achievements have largely resulted from context-adapted policies that enhanced diagnostic and therapeutic access while emphasizing outreach to vulnerable communities. This review synthesizes current advancements in HCV prevention and control and proposes strategic frameworks to expedite global elimination efforts. Full article

Since the onset of the COVID-19 pandemic, remarkable progress has been made in the development of antiviral therapies for SARS-CoV-2. Several direct-acting antivirals, such as remdesivir, molnupiravir, and nirmatrelvir/ritonavir, offer clinical benefits. These agents have significantly contributed to reducing the viral loads and duration of the illness, as well as the disease’s severity and mortality. However, despite these advances, important limitations remain. The continued emergence of resistant SARS-CoV-2 variants highlights the urgent need for adaptable and durable therapeutic strategies. Therefore, this review aims to provide an updated overview of the main antiviral strategies that are used and the discovery of new drugs against SARS-CoV-2, as well as the therapeutic limitations that have shaped clinical management in recent years. The major challenges include resistance associated with viral mutations, limited treatment windows, and unequal access to treatment. Moreover, there is an ongoing need to identify novel compounds with broad-spectrum activity, improved pharmacokinetics, and suitable safety profiles. Combination treatment regimens represent a promising strategy to increase the efficacy of treating COVID-19 while minimizing the potential for resistance. Ideally, these interventions should be safe, affordable, and easy to administer, which would ensure broad global access and equitable treatment and enable control of COVID-19 cases and preparedness for future threats. Full article

Feline infectious peritonitis (FIP) is a severe viral disease with a very high fatality rate. GS-441524 is an adenosine analogue that acts as an antiviral and has shown promise in FIP treatment. However, its commercialization in some regions is not yet authorized. To evaluate the efficacy of GS-441524 based on the published literature, a systematic review was conducted. This systematic review was conducted using PubMed, ScienceDirect, and Google Scholar for studies published from 2018 onwards. Following PRISMA guidelines, 11 studies (totaling 650 FIP cases treated with GS-441524 alone or in combination) were included. Therapeutic efficacy was assessed by FIP form, clinical signs, and dosage. The overall treatment success rate was 84.6%. This rate was higher when GS-441524 was combined with other antivirals and lower in cases of wet FIP or those with neurological complications. Combination therapy with other antivirals may improve outcomes in complicated FIP cases, although further studies are needed. The GS-441524 dosages associated with the best outcomes were 5–10 mg/kg once daily (or equivalent subcutaneous dose), adjusted for FIP type, severity, and presence of neurological/ocular signs. Higher dosages can be used for severe cases or to prevent relapse, but splitting into twice-daily dosing may be necessary to avoid absorption issues. In summary, this synthesis indicates that GS-441524 is a highly promising treatment for FIP, with a high success rate among treated cases. Nevertheless, randomized controlled trials are needed to establish evidence-based therapeutic protocols tailored to different FIP presentations. Full article

Hepatitis C virus (HCV) infection is a major public health concern, with more than 58 million people chronically infected worldwide. The management of HCV, once the domain of specialists only, has been revolutionized by the advent of direct-acting antiviral therapies. To reduce the burden of HCV in the United States (US), emphasis is now being placed on the involvement of primary care physicians in the management of HCV patients. Inclusion of more primary care providers in the HCV diagnosis and treatment initiatives can assist in achieving the goal of HCV elimination, especially in the medically underserved areas. To actively engage in the management of HCV, primary care providers must understand its epidemiology, risk factors, natural history, current treatment regimen, and potential complications. This manuscript reviews these key areas, along with presenting the cost-effectiveness of treatment and evidence-based guidelines for follow-up care in adults with chronic HCV infection who have undergone HCV treatment. Equipped with this foundational knowledge about HCV management, primary care physicians can play a vital role in eliminating HCV. Full article

Background: The advent of direct-acting antivirals (DAAs) has marked a significant milestone in the therapeutic landscape of hepatitis C, greatly improving treatment efficacy. A therapeutic regimen encompassing sofosbuvir (SOF), velpatasvir (VEL), and voxilaprevir (VOX) has demonstrated strong efficacy across all genotypes of the hepatitis C virus (HCV) and has recently been incorporated into the Korean healthcare system. This study aimed to evaluate the real-world efficacy and safety of these antivirals in the South Korean population. Methods: This prospective, multicenter, observational study enrolled patients with chronic HCV treated with SOF/VEL-based regimens at six hospitals between November 2022 and January 2024. DAA-naïve patients received SOF/VEL ± ribavirin for 12 weeks. Patients who had failed prior DAA therapy received SOF/VEL/VOX for 12 weeks. The primary endpoint was a sustained virological response at 12 weeks post-treatment (SVR12). Results: Among 101 patients treated with SOF/VEL, the mean age was 64.71 years, and 40.9% were male. Genotypes 1b and 2 were identified in 40.6% and 59.4% of patients, respectively. Two patients had a history of interferon-based treatment. The mean baseline HCV RNA level was 3,088,097 IU/mL. Cirrhosis was observed in 26.7% of patients (21.8% compensated; 5.0% decompensated). Of the 101 patients, 12 were lost to follow-up. Among the 89 patients who completed follow-up, SVR12 was achieved in 100.0% (89/89), including 5 patients with decompensated cirrhosis. In the SOF/VEL/VOX group, 17 patients were treated. The mean age was 61.84 years, 29.4% were male, and four had compensated cirrhosis. One patient was lost to follow-up. SVR12 was achieved in 100.0% (16/16) of the patients who completed follow-up. No serious adverse events (≥grade 3) were reported in either group during the DAA treatment period. Conclusions: In this first prospective real-world study in South Korea, SOF/VEL-based regimens demonstrated excellent efficacy and safety, achieving 100% SVR12 in the per-protocol population, including patients with cirrhosis and prior treatment failure. Full article

Background: Remdesivir (RDV) is a broad-spectrum antiviral prodrug, which is rapidly metabolized in vivo within cells to the pharmacologically active triphosphate metabolite, GS-443902. On the other hand, the dephosphorylated metabolite GS-441524 is the main form detected in plasma. RDV acts against RNA viruses, and it was the first antiviral drug to receive EMA and FDA approval for treating COVID-19. Nevertheless, its intracellular pharmacokinetics in real life are poorly explored, particularly due to technical challenges. Methods: The aim of this study was to validate an HPLC-MS/MS method for the direct quantification of GS-443902 in peripheral blood mononuclear cells (PBMCs) with a chromatographic separation of 15 min. Results: The method was validated following EMA and FDA guidelines in terms of sensitivity, specificity, accuracy, precision, matrix effect, recovery, carryover, and stability, and then applied to PBMC isolates from a small cohort of patients with severe COVID-19 who received RDV. Conclusions: This work represents the first method for the direct quantification of GS-443902 in PBMCs, with possible future application to intracellular pharmacokinetic studies in different scenarios, such as new oral prodrugs or drug–drug interaction studies. Full article

Background. To meet the WHO’s viral hepatitis elimination goal by 2030, the Minister of Health (Italy) introduced free HCV screening among people born between 1969 and 1989 and those at greater risk (people in the care of the addiction services and detained). Aims. To estimate the following: (i) the prevalence of HCV in hospitalized patients born before 1969 not included in the free HCV screening, (ii) the prevalence of transaminase values outside the range, and (iii) the HBV prevalence in a subgroup of patients. Methods. Anti-HCV antibodies and transaminase values were prospectively evaluated in patients born before 1969 and admitted to the Santa Maria alle Scotte Hospital in Siena. The first screening (October 2021–July 2022) was conducted in the Internal Medicine Division (cohort 0), and the second one (May 2024–October 2024) in Internal Medicine, Gastroenterology, and Geriatric Units (cohorts 1–3), including clinical features and HBV markers in a subgroup of patients. Results. Overall, 774 subjects underwent HCV screening. In the first screening period, 1.4% (8/567) of patients were anti-HCV+, of whom 0.7% were HCV RNA+ (4/567). In the second, 3.9% of patients (8/207) were anti-HCV+ and 0.9% were viremic (2/207). Overall, HCV prevalence was 0.8%. Of 96 patients in the gastroenterology cohort, 8 patients were at risk for occult HBV infection (8.3%). Conclusions. Our study demonstrates a chronic HCV infection prevalence of 0.8% in hospitalised patients born before 1969 and a prevalence of 8.3% of people at risk for occult HBV infection in a subgroup of patients residing in South-Eastern Tuscany, confirming that an opportunistic screening can identify the unrecognized people affected by viral hepatitis. Full article

In HCV-coinfected people with HIV (PWH), there are still conflicting data regarding the long-term metabolic impact of HCV eradication. The aim of the study is to investigate long-term changes in controlled attenuation parameter (CAP) and metabolic profile after sustained virological response (SVR) post-direct acting antivirals (DAAs) in PWH. This is a retrospective observational study including individuals with HIV/HCV coinfection, followed as outpatients at San Raffaele Hospital, who achieved SVR post-DAAs. Individuals were assessed for metabolic parameters before and after the start of DAAs. Univariate and multivariate mixed linear models were calculated to estimate crude mean changes in CAP, metabolic parameters, and weight; slopes were reported with the corresponding 95% confidence intervals (95% CI). Overall, during a median follow-up of 4.02 years (interquartile range, IQR 3.04–4.80), the mean percent increase in CAP was 2.86/year (p < 0. 0001), and the mean decrease in stiffness was –4.28 (p = 0.003). Additionally, total cholesterol (p < 0.0001), high-density lipoprotein (HDL) cholesterol (p = 0.001), triglycerides (p < 0.0001), glucose (p < 0.0001), and Body Mass Index (BMI) (p < 0.0001) increased over time. A long-term follow-up in PWH with SVR post-DAAs showed an overall significant increase in CAP and worsening of the metabolic profile, suggesting a higher risk of developing liver steatosis and metabolic alterations over time. Full article

Background: Hepatitis C virus (HCV) remains a significant public health concern in Thailand, with genotype-specific, drug-dependent variations influencing treatment response and disease progression. Despite the availability of pan-genotypic direct-acting antivirals (DAAs), genotype surveillance remains essential for optimizing national elimination strategies. This study thus aims to characterize the molecular distribution of HCV genotypes in northern Thailand. Methods: We conducted a retrospective molecular epidemiological study on 1737 HCV-infected patients who attended the Clinical Microbiology Service Unit (CMSU) Laboratory, Faculty of Associated Medical Sciences, Chiang Mai University between April 2016 and June 2024. HCV genotyping was performed using Sanger sequencing and reverse hybridization line probe assay (LiPA). Results: Genotype 3 was the most prevalent (36.6%), followed by genotype 1 (35.8%) and genotype 6 (27.2%). Subtype 3a (27.2%) predominated, along with 1a (22.1%), 1b (12.6%), and genotype 6 subtypes including 6c to 6l (13.5%) and 6n (6.6%). Males had a higher prevalence of genotype 1, while genotype 3 was more common among females. Temporal analysis revealed a relative increase in genotype 6 prevalence since 2021. Genotype 6 also exhibited significantly higher median viral loads compared to genotypes 1 and 3 (p < 0.0001). Conclusions: This study provides updated evidence on the shifting distribution of HCV genotypes in northern Thailand, particularly the increasing prevalence of genotype 6. These findings underscore the importance of continued molecular surveillance to guide genotype-specific treatment strategies and support Thailand’s 2030 HCV elimination goals. Full article

Backgrounds: Direct-acting antiviral (DAA) therapy, which achieves a high sustained virological response (SVR) rate, has been established as a standard treatment for patients with hepatitis C virus (HCV) infection. However, the risk factors for postoperative recurrence in patients with HCV-related hepatocellular carcinoma (HCC) detected after the achievement of an SVR by DAAs are unknown. Methods: The clinical records of 95 patients with initial HCV-related HCC detected after DAA-SVR achievement, who underwent liver resection between September 2014 and December 2020, were retrospectively reviewed. Patients with major vascular invasion and/or SVR achievement induced by interferon-based therapy were excluded. In this study, the patients were divided into two groups according to their alcohol intake status: without alcohol abuse (<80 g of ethanol each day for at least 5 years, n = 85) and with (continuous) alcohol abuse (n = 10). The risk factors for recurrence after liver resection were investigated, with special reference to the alcohol intake status. Results: The 3- and 5-year disease-free survival (DFS) rates after liver resection were 68.7% and 55.3%, respectively. Univariate and multivariate analyses identified alcohol abuse [hazard ratio (HR) 3.36, p = 0.004] and tumor size (HR 2.53, p = 0.010) as independent risk factors for postoperative recurrence. The 3- and 5-year postoperative DFS rates were 72.2% and 61.5% for patients without alcohol abuse and 40.0% and 13.3% for those with alcohol abuse (p = 0.001). Conclusions: Continuous alcohol abuse is a risk factor for recurrence after surgery of HCC detected after the achievement of DAA-SVR. Full article

Despite the use of direct-acting antiviral medications to treat hepatitis C virus (HCV), over a million people are newly infected each year, highlighting the need for a prophylactic vaccine. Due to the remarkable genetic diversity of HCV and its many immune evasion mechanisms, an effective vaccine will need to elicit broadly neutralizing antibodies (bNAb). In addition to providing evidence that a prophylactic HCV vaccine is feasible, this review provides an overview of known HCV bNAb targets, common antibody sequence features associated with broad neutralization, and mechanisms of immune escape. Ongoing knowledge gaps in the field and promising future directions are also discussed. Full article

Background/Objectives: Direct-acting antiviral (DAA) therapy has been highly successful in treating chronic hepatitis C (CHC). The nationwide Treatment as Prevention of Hepatitis C (TraP HepC) initiative that was launched in Iceland in 2016 utilized liver stiffness measurements (LSM) to assess liver fibrosis at baseline and follow-up. We aimed to determine changes in liver stiffness among patients following treatment with DAAs and evaluate risk factors associated with hepatic fibrosis. Methods: Eligible CHC patients with liver stiffness of >9.5 kilopascals (kPa) before DAA treatment were invited for a follow-up visit in 2024. Risk factors for cirrhosis were registered, LSM performed, and liver enzymes, blood lipids, and glucose levels measured. Changes in liver stiffness were compared to baseline measurements, and correlations with risk factors were analyzed. Results: A total of 96 patients had LSMs > 9.5 kPa at treatment initiation. During the follow-up period, 61 were eligible for participation, 38 consented, and 34 (35%) died. The total follow-up was 258.3 person-years. The median follow-up period between measurements was 7.1 years. The median liver stiffness decreased from 17.2 kPa to 7.3 kPa (p < 0.01), and 80% of those with cirrhosis (>12.5 kPa) regressed to non-cirrhotic values. High BMI and daily alcohol consumption were significantly associated with increased liver stiffness in 8% of patients. Conclusions: In this single-arm, pre-post pilot study, liver stiffness regressed significantly in 92% of patients who were cured of CHC. Patients with other persistent risk factors following cure, such as obesity and alcohol abuse, were the only patients who had increased liver stiffness at the end of follow-up. Full article

Hepatitis C virus (HCV) remains a global health challenge, contributing to chronic liver disease and hepatocellular carcinoma. In Thailand, HCV prevalence has declined from ~2% in the 1990s due to universal blood screening, harm reduction, and expanded treatment. This narrative review draws on diverse sources—including PubMed and Scopus databases, international and national health websites, government reports, and local communications—to compile epidemiological data, genotype distribution, and elimination strategies, with a focus on Phetchabun province, Thailand, as a model for achieving the World Health Organization’s (WHO) hepatitis C elimination targets. National surveys in 2004, 2014, and 2024 show a prevalence drop from 2.15% to 0.56%. However, HCV persists among high-risk groups, including people who inject drugs, people living with HIV, patients undergoing maintenance hemodialysis, and prisoners. Thailand’s National Health Security Office has expanded treatment access, including universal screening for those born before 1992. The Phetchabun Model, launched in 2017, employs a decentralized test-to-treat strategy. By April 2024, 88.64% (288,203/324,916) of the target population was screened, and 4.88% were anti-HCV positive. Among those tested, 72.61% were HCV-RNA positive, and 88.17% received direct-acting antivirals (i.e., SOF/VEL), achieving >96% sustained virological response. The Phetchabun Model demonstrates a scalable approach for HCV elimination. Addressing testing costs, improving access, and integrating microelimination strategies into national policy are essential to achieving the WHO’s 2030 goals. Full article

Respiratory viruses can cause life-threatening conditions such as sepsis and acute respiratory distress syndrome. However, vaccines and effective antivirals are available for only a limited number of infections. The majority of approved antivirals are direct-acting agents, which target viral proteins essential for infection. Unfortunately, mutations have already emerged that confer resistance to these antivirals. In addition, there is an urgent need for broad-spectrum antivirals to address the unpredictable emergence of new viruses with pandemic potential. One promising strategy involves modulating the innate immune response and cellular signaling. Imiquimod, a Toll-like receptor 7 (TLR7) agonist, has shown efficacy in murine models of influenza and respiratory syncytial virus (RSV). Additionally, it demonstrates antiviral activity against herpes simplex virus type 1 (HSV-1) and RSV independent of the TLR7/nuclear factor kappa B (NF-κB) pathway, with protein kinase A (PKA) as a crucial downstream effector. In this study, we demonstrate that imiquimod exhibits concentration-dependent antiviral activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and canine coronavirus (CCoV) in epithelial cells, underscoring its broad-spectrum action against coronaviruses. Moreover, its anti-coronavirus effect appears to be independent of the TLR/NF-κB and PKA/exchange protein directly activated by cyclic adenosine monophosphate (EPAC) pathways and may instead be linked to the activation of the mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway. The ability of imiquimod to inhibit coronavirus replication via the MEK/ERK pathway, coupled with its immunomodulatory properties, highlights its potential as a broad-spectrum antiviral. Full article

The replication machinery of SARS-CoV-2 is a primary target for therapeutic intervention, and has led to significant progress in antiviral medication discovery. This review consolidates contemporary molecular insights into viral replication and rigorously assesses treatment methods at different phases of viruses’ clinical development. Direct-acting antivirals, such as nucleoside analogs (e.g., remdesivir, molnupiravir) and protease inhibitors (e.g., nirmatrelvir), have shown clinical effectiveness in diminishing morbidity and hospitalization rates. Simultaneously, host-targeted medicines like baricitinib, camostat, and brequinar leverage critical host–virus interactions, providing additional pathways to reduce viral replication while possibly minimizing the development of resistance. Notwithstanding these advancements, constraints in distribution methods, antiviral longevity, and the risk of mutational evasion demand novel strategies. Promising investigational approaches encompass CRISPR-mediated RNA degradation systems, inhalable siRNA-nanoparticle conjugates, and molecular glue degraders that target host and viral proteins. Furthermore, next-generation treatments aimed at underutilized enzyme domains (e.g., NiRAN, ExoN) and host chaperone systems (e.g., TRiC complex) signify a transformative approach in antiviral targeting. The integration of high-throughput phenotypic screening, AI-driven medication repurposing, and systems virology is transforming the antiviral discovery field. An ongoing interdisciplinary endeavor is necessary to convert these findings into versatile, resistance-resistant antiviral strategies that are applicable beyond the present pandemic and in future coronavirus epidemics. Full article