Hepatitis C virus genotypes and viral concentrations in participants of a general population survey in the United States

Therapeutic approaches for chronic hepatitis C: a concise review

Hepatitis C virus (HCV) infection is a significant global health concern, prompting the need for effective treatment strategies. This in-depth review critically assesses the landscape of HCV treatment, drawing parallels between traditional interferon/ribavirin therapy historically pivotal in HCV management and herbal approaches rooted in traditional and complementary medicine. Advancements in therapeutic development and enhanced clinical outcomes axis on a comprehensive understanding of the diverse HCV genome, its natural variations, pathogenesis, and the impact of dietary, social, environmental, and economic factors. A thorough analysis was conducted through reputable sources such as Science Direct, PubMed, Scopus, Web of Science, books, and dissertations. This review primarily focuses on the intricate nature of HCV genomes and explores the potential of botanical drugs in both preventing and treating HCV infections.

Current standard values of health utility scores for evaluating cost-effectiveness in liver disease: A meta-analysis

BACKGROUND

Health utility assessments have been developed for various conditions, including chronic liver disease. Health utility scores are required for socio-economic evaluations, which can aid the distribution of national budgets. However, the standard health utility assessment scores for specific health conditions are largely unknown.

AIM

To summarize the health utility scores, including the EuroQOL 5-dimensions 5-levels (EQ-5D-5L), EuroQol-visual analogue scale, short from-36 (SF-36), RAND-36, and Health Utilities Index (HUI)-Mark2/Mark3 scores, for the normal population and chronic liver disease patients.

METHODS

A systematic literature search of PubMed and MEDLINE, including the Cochrane Library, was performed. Meta-analysis was performed using the RevMan software. Multiple means and standard deviations were combined using the StatsToDo online web program.

RESULTS

The EQ-5D-5L and SF-36 can be used for health utility evaluations during antiviral therapy for hepatitis C. HUI-Mark2/Mark3 indicated that the health utility scores of hepatitis B patients are roughly 30% better than those of hepatitis C patients.

CONCLUSION

The EQ-5D-5L is the most popular questionnaire for health utility assessments. Health assessments that allow free registration would be useful for evaluating health utility in patients with liver disease.

Utilization of HCV Viremic Kidneys with Genotyping/Subtyping-Free Sofosbuvir/Velpatasvir Treatment Strategy: Experience from China

Background. Owing to the advent of pangenotypic direct-acting antiviral agents (DAAs) for hepatitis C virus (HCV) treatment, utilization of HCV-infected deceased donor kidneys with simplified genotyping/subtyping-free sofosbuvir/velpatasvir (SOF/VEL) treatment strategy is now becoming a promising strategy for expanding the organ donor pool. Methods. This retrospective, comparative, single-center study included HCV viremic donor kidneys that were transplanted to 9 HCV-positive (HCV Ab-positive) recipients (D+/R+ group) and 14 HCV-negative recipients (D+/R- group) from May 2018 to January 2021. Both groups received prophylaxis with SOF/VEL treatment within 1-week posttransplant devoid of HCV genotyping/subtyping. The primary outcomes were sustained virologic response 12 weeks after completion of therapy (SVR12) and graft survival at 1-year posttransplant. Results. Baseline characteristics were similar between the HCV D+/R- and D+/R+ groups. The mean age of all recipients was $39.09\pm 9.65$ (SD) years, and 73.9% were male. A total of 92.9% (13 out of 14) recipients had pretreatment HCV viremia in the D+/R- group. The pretreatment HCV viral load in the D+/R+ group (5.98, log 10 IU/mL; IQR, 5.28-6.53) was significantly higher than that in the D+/R- group (3.61, log 10 IU/mL; IQR, 2.57-4.57). After SOF/VEL treatment, SVR12 was achieved in all recipients, with a 100% 1-year patient and graft survival rates. The D+/R+ group had a higher incidence of abnormal liver function (44.4% vs. 7.1%). No significant difference was observed between the two groups in terms of DGF, acute rejection, ALT, serum creatinine, and eGFR within 1-year posttransplant. No severe adverse events associated with either HCV viremia or SOF/VEL were observed. Conclusions. Using a simplified genotyping/subtyping-free SOF/VEL treatment strategy, kidneys from hepatitis C viremic donors for both infected and uninfected recipients presented with safe, excellent, and comparable 1-year outcomes, which can safely expand the donor pool. HCV-positive donor kidneys should be utilized regularly, regardless of the recipient’s HCV status.

Mathematical modeling of plus-strand RNA virus replication to identify broad-spectrum antiviral treatment strategies

Plus-strand RNA viruses are the largest group of viruses. Many are human pathogens that inflict a socio-economic burden. Interestingly, plus-strand RNA viruses share remarkable similarities in their replication. A hallmark of plus-strand RNA viruses is the remodeling of intracellular membranes to establish replication organelles (so-called "replication factories"), which provide a protected environment for the replicase complex, consisting of the viral genome and proteins necessary for viral RNA synthesis. In the current study, we investigate pan-viral similarities and virus-specific differences in the life cycle of this highly relevant group of viruses. We first measured the kinetics of viral RNA, viral protein, and infectious virus particle production of hepatitis C virus (HCV), dengue virus (DENV), and coxsackievirus B3 (CVB3) in the immuno-compromised Huh7 cell line and thus without perturbations by an intrinsic immune response. Based on these measurements, we developed a detailed mathematical model of the replication of HCV, DENV, and CVB3 and show that only small virus-specific changes in the model were necessary to describe the in vitro dynamics of the different viruses. Our model correctly predicted virus-specific mechanisms such as host cell translation shut off and different kinetics of replication organelles. Further, our model suggests that the ability to suppress or shut down host cell mRNA translation may be a key factor for in vitro replication efficiency which may determine acute self-limited or chronic infection. We further analyzed potential broad-spectrum antiviral treatment options in silico and found that targeting viral RNA translation, especially polyprotein cleavage, and viral RNA synthesis may be the most promising drug targets for all plus-strand RNA viruses. Moreover, we found that targeting only the formation of replicase complexes did not stop the viral replication in vitro early in infection, while inhibiting intracellular trafficking processes may even lead to amplified viral growth.

Author summary

Plus-strand RNA viruses comprise a large group of related and medically relevant viruses. The current global pandemic of COVID-19 caused by the SARS-coronavirus-2 as well as the constant spread of diseases such as dengue and chikungunya fever show the necessity of a comprehensive and precise analysis of plus-strand RNA virus infections. Plus-strand RNA viruses share similarities in their life cycle. To understand their within-host replication strategies, we developed a mathematical model that studies pan-viral similarities and virus-specific differences of three plus-strand RNA viruses, namely hepatitis C, dengue, and coxsackievirus. By fitting our model to in vitro data, we found that only small virus-specific variations in the model were required to describe the dynamics of all three viruses. Furthermore, our model predicted that ribosomes involved in viral RNA translation seem to be a key player in plus-strand RNA replication efficiency, which may determine acute or chronic infection outcome. Furthermore, our in-silico drug treatment analysis suggests that targeting viral proteases involved in polyprotein cleavage, in combination with viral RNA replication, may represent promising drug targets with broad-spectrum antiviral activity.

Genotype Distribution and Demographic Characteristics of Hepatitis C Virus NAT Yield Cases among US Blood Donors

BACKGROUND

HCV infection rates among U.S. blood donors have been well characterized; however, few studies evaluate HCV genotypes among blood donors. Monitoring trends in disease and demographic patterns contribute to understanding the safety of the blood supply. Here we examined the demographic characteristics and the distribution of HCV genotypes/subgenotypes for nearly a 16-year period among blood donors confirmed positive for HCV RNA but antibody negative (defined as NAT yield).

METHODS

A retrospective assessment of demographic characteristics and testing data was used to determine temporal trends and geographical distribution of HCV genotypes/subgenotypes among American Red Cross blood donors confirmed positive as HCV-NAT yield.

RESULTS

From 2003-2018, 343 donors (0.38 per 100,000 donations; 95% CI, 0.35-0.43) confirmed positive as HCV-NAT-yield cases. Temporal analysis revealed a significant increase in HCV-NAT-yield cases of 54.1% between 2009-2014 (p=0.014), followed by a significant decline of 31.4% between 2015-2018 (p=0.002). Significantly more HCV-NAT-yield cases were detected among first-time donors, non-Hispanic Whites, donors aged 20-29 years, equally likely to be males as females, with the highest frequency in the South (0.52/100,000 donations). Subgenotype 1a (49.6%) was most frequent, followed by 3a (18.7%), 2b (12.5%), 1b (8.5%) and 2a (1.7%).

CONCLUSION

Voluntary non-remunerated blood donors are at low risk for HCV infection. Since 2015, the frequency of HCV-NAT-yield cases decreased despite an increase of acute HCV infection in the general population. HCV subgenotypes 1a and 3a continue to remain predominant among U.S. blood donors with recent HCV infection.

Hepatitis C Virus Exposure and Infection in the Perinatal Period

BACKGROUND

Hepatitis C virus infection is a leading cause of blood-borne hepatitis disease worldwide. Hepatitis C is a silent liver disease that, without treatment, leads to late-onset complications, including chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma, in 10-40% of patients.

OBJECTIVE

This study aimed to review the epidemiology, clinical features, diagnosis, treatment, and prevention of hepatitis C among perinatally exposed children.

METHODS

Public databases, including MEDLINE and PubMed, and websites from the Centers for Disease Control and Prevention, the Food and Drug Administration, the World Health Organization, and the National Institutes of Health were searched for relevant articles published between 2006 and 2021.

RESULTS

The prevalence of hepatitis C has increased among women of childbearing age in the United States and is associated with risk factors, such as intravenous drug use, health inequities, and low socioeconomic background. Infants born to hepatitis C virus-infected mothers have a 6% risk of vertical transmission, and among those infected, 75% will develop chronic hepatitis C and late complications. However, hepatitis C-exposed infants are frequently lost to follow-up, and those infected have delayed diagnosis and treatment and are at high risk for late-onset complications. Direct- acting antivirals and the establishment of effective treatment guidelines cure hepatitis C virus infections.

CONCLUSION

Hepatitis C predominantly affects underserved communities. Early screening of mothers and infants is critical for the diagnosis, treatment, and prevention of chronic infections and lateonset complications. New policies are needed to address hepatitis C health care inequities affecting mothers and infants in the United States.

Distribution of hepatitis C virus genotypes in Punjab region, Pakistan, based on a study of 4177 specimens

Hepatitis C virus (HCV) is a heterogenetic infectious agent that affects a huge proportion of population around the globe. Diverse distribution of multiple subtypes of HCV makes it mandatory and remarkably imperative to understand the genotypic distribution in target population. It could serve as an indictive guideline for the improvement of diagnostic methodologies, and development of effective therapies against this viral infection, in order to improve the infected patients' quality of life. This study included HCV infected patients presented to the diagnostic facility of the Centre for Applied Molecular Biology, University of Punjab, Lahore, between 2016 and 2019. During the 4 years of study, samples were collected from 4177 subjects. Our data revealed no significant differences regarding the prevalence of various genotypes between genders in the adult population. Genotyping was carried out by following the Ohno protocol. The obtained results shown that genotype 3a is the most frequent genotype and accounts for 66.29% of cases. Among other genotypes, 1a is 2.11%, 1b is 0.07%, 3b is 1.89%, 5a is 0.02%, while genome of 28.23% patients was untypable; 1.22% of the samples were non-detectable as viremic. An important concern is that this untypable genome in HCV infected patients may indicate possible mutation of HCV.

Convex hulls in hamming space enable efficient search for similarity and clustering of genomic sequences

Background

In molecular epidemiology, comparison of intra-host viral variants among infected persons is frequently used for tracing transmissions in human population and detecting viral infection outbreaks. Application of Ultra-Deep Sequencing (UDS) immensely increases the sensitivity of transmission detection but brings considerable computational challenges when comparing all pairs of sequences. We developed a new population comparison method based on convex hulls in hamming space. We applied this method to a large set of UDS samples obtained from unrelated cases infected with hepatitis C virus (HCV) and compared its performance with three previously published methods.

Results

The convex hull in hamming space is a data structure that provides information on: (1) average hamming distance within the set, (2) average hamming distance between two sets; (3) closeness centrality of each sequence; and (4) lower and upper bound of all the pairwise distances among the members of two sets. This filtering strategy rapidly and correctly removes 96.2% of all pairwise HCV sample comparisons, outperforming all previous methods. The convex hull distance (CHD) algorithm showed variable performance depending on sequence heterogeneity of the studied populations in real and simulated datasets, suggesting the possibility of using clustering methods to improve the performance. To address this issue, we developed a new clustering algorithm, k-hulls, that reduces heterogeneity of the convex hull. This efficient algorithm is an extension of the k-means algorithm and can be used with any type of categorical data. It is 6.8-times more accurate than k-mode, a previously developed clustering algorithm for categorical data.

Conclusions

CHD is a fast and efficient filtering strategy for massively reducing the computational burden of pairwise comparison among large samples of sequences, and thus, aiding the calculation of transmission links among infected individuals using threshold-based methods. In addition, the convex hull efficiently obtains important summary metrics for intra-host viral populations.

Cost-effectiveness of Universal and Targeted Hepatitis C Virus Screening in the United States

Importance

Between 2 and 3.5 million people live with chronic hepatitis C virus (HCV) infection in the US, most of whom (approximately 75%) are not aware of their disease. Despite the availability of effective HCV treatment in the early stages of infection, HCV will result in thousands of deaths in the next decade in the US.

Objective

To investigate the cost-effectiveness of universal screening for all US adults aged 18 years or older for HCV in the US and of targeted screening of people who inject drugs.

Design, Setting, and Participants

This simulated economic evaluation used cohort analyses in a Markov model to perform a 10 000-participant Monte Carlo microsimulation trail to evaluate the cost-effectiveness of HCV screening programs, and compared screening programs targeting people who inject drugs with universal screening of US adults age 18 years or older. Data were analyzed in December 2019.

Exposures

Cost per quality-adjusted life-year (QALY).

Main Outcomes and Measures

Cost per QALY gained.

Results

In a 10 000 Monte Carlo microsimulation trail that compared a baseline of individuals aged 40 years (men and women) and people who inject drugs in the US, screening and treatment for HCV were estimated to increase total costs by $10 457 per person and increase QALYs by 0.23 (approximately 3 months), providing an incremental cost-effectiveness ratio of $45 465 per QALY. Also, universal screening and treatment for HCV are estimated to increase total costs by $2845 per person and increase QALYs by 0.01, providing an incremental cost-effectiveness ratio of $291 277 per QALY.

Conclusions and Relevance

The findings of this study suggest that HCV screening for people who inject drugs may be a cost-effective intervention to combat HCV infection in the US, which could potentially decrease the risk of untreated HCV infection and liver-related mortality.

Highlights for Dental Care as a Hepatitis C Risk Factor: A Review of Literature

Hepatitis C (HCV) is a viral infection that affects an estimated 71 million people worldwide, with over 1 million new infections yearly. While medical treatments exist, HCV continues to be a significant public health concern. Primary prevention and transmission risk factor identification remain key in helping decrease disease prevalence. While intravenous drug use, healthcare exposure (i.e. blood transfusions and surgical care), and body modification (i.e. tattooing and piercings) are well accepted risk factors for HCV transmission, others remain controversial. Because dental practice is often associated with procedures and bleeding, the possibility of HCV transmission seemed reasonable to investigate. Here, we review the evidence for dental care as a potential risk factor for HCV transmission. We identified a total of 1,180 manuscripts related to HCV and dental care, of which 26 manuscripts were included in the study after exclusionary criteria were applied. As per our review of the available literature, in the developing world, the improper use of sterile technique and lack of provider education likely increases the risk of HCV transmission during dental care. In developed nations, on the other hand, general dental care does not appear to be a significant risk factor for HCV transmission in non-intravenous drug user patients; although, the improper use and reuse of anesthetics during procedures poses a rare potential risk for viral transmission.

Management of Hepatitis C Infection in children in the era of Direct-acting Antiviral Agents

Chronic hepatitis C certainly is a global health burden in children as well as in adults. Spontaneous viral clearance can occur in early childhood but is uncommon thereafter. Although the majority of cases are asymptomatic during childhood and young adulthood, without an effective treatment, children who acquire HCV via vertical transmission can develop chronic liver disease and other complications including end-stage liver disease and hepatocellular carcinoma in adulthood. Efforts from worldwide health organizations, the pharmaceutical industry, and clinical and research institutions have resulted in very effective interferon-free therapy with direct-acting antiviral agents (DAAs) for HCV-infected children. In this manuscript, we will briefly review the epidemiology of HCV in children, historic treatment, current published data on DAAs in children and conclude with suggestions for management of the child with HCV in the era of DAAs.

Interferon at the cellular, individual, and population level in hepatitis C virus infection: Its role in the interferon-free treatment era

The advent of powerful direct-acting antiviral agents (DAAs) has revolutionized the treatment of hepatitis C. DAAs cure nearly all patients with short duration, oral treatments. Significant efforts are now underway to optimize DAA-based treatments. We discuss the potential role of interferon in this optimization. Clinical studies present compelling evidence that DAAs perform better in treatment-naive individuals than in individuals who previously failed treatment with interferon, a surprising correlation because interferon and DAAs are thought to act independently. Recent mathematical models explore a mechanistic hypothesis underlying this correlation. The hypothesis invokes the action of interferon at the cellular, individual, and population levels. Strong interferon responses prevent the productive infection of cells, reduce viral replication, and impede the development of resistance to DAAs in infected individuals and improve cure rates elicited by DAAs in treated populations. The models develop descriptions of these processes, integrate them into a comprehensive framework, and capture clinical data quantitatively, providing a successful test of the hypothesis. Individuals with strong endogenous interferon responses thus present a promising subpopulation for reducing DAA treatment durations. This review discusses the conceptual advances made by the models, highlights the new insights they unravel, and examines their applicability to optimize DAA-based treatments.

Mutational pathway maps and founder effects define the within-host spectrum of hepatitis C virus mutants resistant to drugs

Knowledge of the within-host frequencies of resistance-associated amino acid variants (RAVs) is important to the identification of optimal drug combinations for the treatment of hepatitis C virus (HCV) infection. Multiple RAVs may exist in infected individuals, often below detection limits, at any resistance locus, defining the diversity of accessible resistance pathways. We developed a multiscale mathematical model to estimate the pre-treatment frequencies of the entire spectrum of mutants at chosen loci. Using a codon-level description of amino acids, we performed stochastic simulations of intracellular dynamics with every possible nucleotide variant as the infecting strain and estimated the relative infectivity of each variant and the resulting distribution of variants produced. We employed these quantities in a deterministic multi-strain model of extracellular dynamics and estimated mutant frequencies. Our predictions captured database frequencies of the RAV R155K, resistant to NS3/4A protease inhibitors, presenting a successful test of our formalism. We found that mutational pathway maps, interconnecting all viable mutants, and strong founder effects determined the mutant spectrum. The spectra were vastly different for HCV genotypes 1a and 1b, underlying their differential responses to drugs. Using a fitness landscape determined recently, we estimated that 13 amino acid variants, encoded by 44 codons, exist at the residue 93 of the NS5A protein, illustrating the massive diversity of accessible resistance pathways at specific loci. Accounting for this diversity, which our model enables, would help optimize drug combinations. Our model may be applied to describe the within-host evolution of other flaviviruses and inform vaccine design strategies.

Impact of Preexisting Hepatitis C Virus Genotype 6 NS3, NS5A, and NS5B Polymorphisms on the In Vitro Potency of Direct-Acting Antiviral Agents

HCV genotype 6 (GT-6) is found predominantly in East and Southeast Asia. Clinical studies have focused on patients infected with hepatitis C virus (HCV) GT-6a, where high sustained virologic response (SVR) rates to direct-acting antivirals (DAAs) have been achieved. However, GT-6 is highly diverse, with 29 reported subtypes. We explored the diversity of GT-6 polymorphisms at residues associated with DAA resistance, their impact on DAA in vitro potency when evaluated in a GT-6a consensus replicon, and their association with specific GT-6 subtypes. GT-6 sequences from 25 patient-derived samples and 105 sequences from the U.S. HCV database were compared, and substitutions at resistance-associated residue positions were phenotyped against different DAAs. Preexisting resistance-associated substitutions (RASs) to NS3 protease (A156V and D168E) and NS5B nucleotide (L159F and S282C) inhibitors were rare (<4%). Preexisting RASs to NS5A inhibitors were common, especially at L28 (A/F/G/M/T/V) and R30 (E/N/S). In vitro susceptibilities of NS5A-L28A and -L28T were dramatically reduced against all tested NS5A drugs (90% effective concentration [EC₉₀] range, 119 to 2,032 nM) compared with susceptibilities against a GT-6a consensus replicon (EC₉₀ range, 0.1 to 19 nM). These L28 RASs preexisted in combination with R30S (EC₉₀ [L28A-R30S] of ≥720 nM or EC₉₀ [L28T-R30S] of ≥128 nM against tested DAAs) or as L28T-L31I (EC₉₀ [tested DAAs] of >5,000 nM) and were detected in evaluated GT-6b and -6f sequences. NS5A-L28A-R30A, observed in GT-6r, did not replicate. In conclusion, HCV GT-6b, GT-6f, and GT-6r sequences harbored highly resistant RASs to all evaluated NS5A drugs. Therefore, monitoring SVR in patients infected with these GT-6 subtypes treated with NS5A drug-containing regimens is suggested to confirm any association between noted NS5A polymorphisms and treatment failure.

Race, Age, and Geography Impact Hepatitis C Genotype Distribution in the United States

GOALS

To determine the impact of geography and patient characteristics on hepatitis C virus (HCV) genotype and subtype distribution in a large sample of patients under routine clinical care BACKGROUND:: HCV genotype impacts disease course and response to treatment. Although several studies have reported genotype distribution within specific US populations, there are no comprehensive descriptions in large, geographically diverse cohorts.

STUDY

Using data from the Chronic Hepatitis Cohort Study, we present the distribution of HCV genotypes (GT) and subtypes (ST) among a racially diverse cohort of over 8000 HCV-infected patients from four large US health systems.

RESULTS

Genotype distribution varied significantly by geographic and demographic factors. In age-adjusted analyses, African American patients had significantly higher prevalence of GT1 (85%) than other racial categories, largely driven by a markedly higher proportion of GT1 subtype b (∼34%) than in Asian/other (24%) and white (21%) patients. GT3 represented an increasing proportion of infections as birth decade progressed, from 4% in patients born before 1946 to 18% of those born after 1976. Within the cohort of "living/uncured" patients, highly elevated alanine aminotransferase (>2 times the upper limit of normal) was significantly more common in GT3 patients, whereas Fibrosis-4 Index scores indicative of cirrhosis were most common in the combined group of GT4&6 patients.

CONCLUSION

Distribution of HCV genotypes and subtypes in the United States is more variable than suggested by previous national-level estimates and single-center studies. "Real-world" prevalence data may improve targeting of prevention, screening, and treatment efforts for hepatitis C.

Future Considerations for the Evaluation of Hepatitis C Virus Treatments in Pan-Genotypic Therapy for Noncirrhotic Treatment-Naive Patients

Given the recent approval of the first pan-genotypic chronic hepatitis C virus (HCV) therapy, managed care, health systems, and clinicians will need to evaluate current practices related to essential laboratory assessments used to select therapy. Historically, clinicians and payers required a battery of tests to determine HCV genotype, viral load, degree of fibrosis, and organ function. In light of current and forthcoming approvals of pan-genotypic therapy, clinicians and payers can expect a more competitive marketplace and a downward curve in the price of therapy. Ultimately, this development will lead to the cost of screenings and assessments having an increased role in selecting an optimal HCV therapy.

DISCLOSURES

No outside funding supported this study. The authors have nothing to disclose. All authors contributed to study concept and design. Calabrese took the lead in data collection, along with Shaya. Data interpretation was performed by Calabrese and Hynicka, along with Rodriguez de Bittner and Shaya. The manuscript was written and revised by Calabrese and Hynicka, along with Rodriguez de Bittner and Shaya.

Modelling how responsiveness to interferon improves interferon-free treatment of hepatitis C virus infection

Direct-acting antiviral agents (DAAs) for hepatitis C treatment tend to fare better in individuals who are also likely to respond well to interferon-alpha (IFN), a surprising correlation given that DAAs target specific viral proteins whereas IFN triggers a generic antiviral immune response. Here, we posit a causal relationship between IFN-responsiveness and DAA treatment outcome. IFN-responsiveness restricts viral replication, which would prevent the growth of viral variants resistant to DAAs and improve treatment outcome. To test this hypothesis, we developed a multiscale mathematical model integrating IFN-responsiveness at the cellular level, viral kinetics and evolution leading to drug resistance at the individual level, and treatment outcome at the population level. Model predictions quantitatively captured data from over 50 clinical trials demonstrating poorer response to DAAs in previous non-responders to IFN than treatment-naïve individuals, presenting strong evidence supporting the hypothesis. Model predictions additionally described several unexplained clinical observations, viz., the percentages of infected individuals who 1) spontaneously clear HCV, 2) get chronically infected but respond to IFN-based therapy, and 3) fail IFN-based therapy but respond to DAA-based therapy, resulting in a comprehensive understanding of HCV infection and treatment. An implication of the causal relationship is that failure of DAA-based treatments may be averted by adding IFN, a strategy of potential use in settings with limited access to DAAs. A second, wider implication is that individuals with greater IFN-responsiveness would require shorter DAA-based treatment durations, presenting a basis and a promising population for response-guided therapy.

The American Society of Transplantation Consensus Conference on the Use of Hepatitis C Viremic Donors in Solid Organ Transplantation

The availability of direct-acting antiviral agents for the treatment of hepatitis C virus (HCV) infection has resulted in a profound shift in the approach to the management of this infection. These changes have affected the practice of solid organ transplantation by altering the framework by which patients with end-stage organ disease are managed and receive organ transplants. The high level of safety and efficacy of these medications in patients with chronic HCV infection provides the opportunity to explore their use in the setting of transplanting organs from HCV-viremic patients into non-HCV-viremic recipients. Because these organs are frequently discarded and typically come from younger donors, this approach has the potential to save lives on the solid organ transplant waitlist. Therefore, an urgent need exists for prospective research protocols that study the risk versus benefit of using organs for hepatitis C-infected donors. In response to this rapidly changing practice and the need for scientific study and consensus, the American Society of Transplantation convened a meeting of experts to review current data and develop the framework for the study of using HCV viremic organs in solid organ transplantation.

Hepatitis B and C

Chronic viral hepatitis is a global health threat and financial burden. Hepatitis B and C viruses (HBV and HCV) are the most common causes of chronic viral hepatitis in the United States. Most cases are asymptomatic before adulthood. Research has resulted in effective therapy for HCV and the promise of effective therapies for HBV. For HCV, therapy is pegylated interferon and ribavirin. Clinical trials with effective direct-acting antiviral agents are underway in pediatrics. For HBV, approved agents are alpha-interferon, lamivudine, adefovir, tenofovir, and entecavir. However, treatment seldom results in functional cure and more effective therapies are urgently needed.

Efficient detection of viral transmissions with Next-Generation Sequencing data

BACKGROUND

Hepatitis C is a major public health problem in the United States and worldwide. Outbreaks of hepatitis C virus (HCV) infections associated with unsafe injection practices, drug diversion, and other exposures to blood are difficult to detect and investigate. Molecular analysis has been frequently used in the study of HCV outbreaks and transmission chains; helping identify a cluster of sequences as linked by transmission if their genetic distances are below a previously defined threshold. However, HCV exists as a population of numerous variants in each infected individual and it has been observed that minority variants in the source are often the ones responsible for transmission, a situation that precludes the use of a single sequence per individual because many such transmissions would be missed. The use of Next-Generation Sequencing immensely increases the sensitivity of transmission detection but brings a considerable computational challenge because all sequences need to be compared among all pairs of samples.

METHODS

We developed a three-step strategy that filters pairs of samples according to different criteria: (i) a k-mer bloom filter, (ii) a Levenhstein filter and (iii) a filter of identical sequences. We applied these three filters on a set of samples that cover the spectrum of genetic relationships among HCV cases, from being part of the same transmission cluster, to belonging to different subtypes.

RESULTS

Our three-step filtering strategy rapidly removes 85.1% of all the pairwise sample comparisons and 91.0% of all pairwise sequence comparisons, accurately establishing which pairs of HCV samples are below the relatedness threshold.

CONCLUSIONS

We present a fast and efficient three-step filtering strategy that removes most sequence comparisons and accurately establishes transmission links of any threshold-based method. This highly efficient workflow will allow a faster response and molecular detection capacity, improving the rate of detection of viral transmissions with molecular data.

The value of cure associated with treating treatment-naïve chronic hepatitis C genotype 1: Are the new all-oral regimens good value to society?

BACKGROUND & AIMS

All-oral regimens are associated with high cure rates in hepatitis C virus-genotype 1 (HCV-GT1) patients. Our aim was to assess the value of cure to the society for treating HCV infection.

METHODS

Markov model for HCV-GT1 projected long-term health outcomes, life years, and quality-adjusted life years (QALYs) gained. The model compared second-generation triple (sofosbuvir+pegylated interferon+ribavirin [PR] and simeprevir+PR) and all-oral (ledipasvir/sofosbuvir and ombitasvir+paritaprevir/ritonavir+dasabuvir±ribavirin) therapies with no treatment. Sustained virological response rates were based on Phase III RCTs. We assumed that 80% and 95% of HCV-GT1 patients were eligible for second-generation triple and all-oral regimens. Transition probabilities, utility and mortality were based on literature review. The value of cure was calculated by the difference in the savings from the economic gains associated with additional QALYs.

RESULTS

Model estimated 1.52 million treatment-naïve HCV-GT1 patients in the US. Treating all eligible HCV-GT1 patients with second-generation triple and all-oral therapies resulted in 3.2 million and 4.8 million additional QALYs gained compared to no treatment respectively. Using $50,000 as value of QALY, these regimens lead to savings of $185 billion and $299 billion; costs of these regimens were $109 billion and $128 billion. The value of cure with second-generation triple and all-oral regimens was $55 billion and $111 billion, when we conservatively assumed only drug costs. Cost savings were greater for HCV-GT1 patient cured with cirrhosis compared to patients without cirrhosis.

CONCLUSIONS

The recent evolution of regimens for HCV GT1 has increased efficacy and value of cure.

Access to New Medications for Hepatitis C for Medicaid Members: A Retrospective Cohort Study

BACKGROUND

Sofosbuvir (SOF)- or simeprevir (SIM)-containing regimens are highly effective for treating chronic hepatitis C virus (HCV) infection. These regimens, however, are expensive. Most payers have implemented prior authorization (PA) requirements to ensure that patients who can benefit most have priority for these medications. While many Medicaid programs limit access to those with advanced disease or to members who do not have active substance use disorder (SUD), the Massachusetts Medicaid (MassHealth) Primary Care Clinician (PCC) plan does not limit access based on disease severity or presence of SUD. Evaluating PA requests for SOF and/or SIM among MassHealth members will offer a useful example of early uptake among Medicaid members and will identify patient groups who might face barriers to treatment at the provider or patient level.

OBJECTIVES

To (a) evaluate the percentage of MassHealth PCC members with HCV who had a PA request, along with the percentage of requests approved, and (b) identify characteristics associated with PA requests for SOF or SIM among Massachusetts Medicaid (MassHealth) members with HCV.

METHODS

This retrospective cohort study used enrollment, medical claims, and PA request data from MassHealth PCC members from December 6, 2012, to July 31, 2014. The sample included members with 1 or more claims with an ICD-9-CM code for HCV during this time who were continuously enrolled from December 6, 2013, to July 31, 2014. Enrollment and medical claims data for the cohort with HCV were linked to a database containing information collected from PA requests. The overall percentage of members with HCV and a PA request for SOF and/or SIM between December 6, 2013, and July 31, 2014, and the percentage of requests approved were calculated. Chi-square statistics were used to compare demographic and clinical characteristics among members with HCV who did and did not have a request. Logistic regression was used to estimate the strength of associations between patient characteristics and a PA treatment request, adjusting for clinical and demographic variables.

RESULTS

Of 6,849 members identified with HCV, 346 (5.1%) had a PA request for SOF and/or SIM submitted to MassHealth. Compared with members with HCV who did not have a PA request for SOF or SIM, those with a PA request for these new treatments were more likely to be male (P = 0.01), older (P < 0.001), white race (P = 0.04), have standard MassHealth insurance (P = 0.01), and less likely to be homeless (P < 0.001). Members with a PA request were also more likely to have been treated for HCV in the past year and have advanced disease (hepatic decompensation, cirrhosis, or liver transplant) but less likely to have SUD (P < 0.001 for each). Ninety percent of requests for SOF or SIM were approved; few demographic or clinical characteristics were associated with approval. In adjusted analyses, predictors of PA request were aged 50-64 years (odds ratio (OR) = 2.0, 95% CI = 1.1-3.7 vs. aged < 30 years); hepatic decompensation (OR = 1.6, 95% CI = 1.2-2.3); cirrhosis (OR = 3.0, 95% CI = 2.2-4.1); liver transplant (OR = 3.0, 95% CI = 1.4-6.5); substance use (OR = 0.6, 95% CI = 0.5-0.8); recent HCV treatment (OR = 1.6, 95% CI = 1.0-2.6); comorbidity (OR = 0.95, 95% CI = 0.91-0.98) for 1-unit increase in Diagnostic Cost Group score; and care at a hospital outpatient department (OR = 2.0, 95% CI = 1.2-3.2 vs. group practice).

CONCLUSIONS

Antiviral treatment with SOF and/or SIM was requested for a relatively small proportion of MassHealth members with HCV, with nearly all approved. Prescriber prioritization or patient barriers to care, rather than the PA process, determined access to treatment in this Medicaid population. Support may be needed to ensure patients with SUD benefit from advances in HCV treatment.

DISCLOSURES

No outside funding supported this research. Internal funding was provided by the Commonwealth of Massachusetts. Lavitas has received compensation from University of Tennessee Advanced Studies in Medicine for development of CPE activity. Graham has consulted for the National Viral Hepatitis Roundtable and the Department of Health and Human Services, has received payment from Medscape for CME development, and is employed by Trek Therapeutics. Jeffrey has received payment for guest lectures at Boston University and Harvard University. Study concept and design were primarily contributed by Clark and Clements, along with Graham, Lenz, and Jeffrey. Kunte collected the data, which were interpreted by Graham, Lenz, and Jeffrey, with assistance from Lavitas, Clark, and Clements. The manuscript was written primarily by Clements, along with O'Connell and assisted by Graham, and revised by all the authors.

Development and validation of a real-time, reverse transcription PCR assay for rapid and low-cost genotyping of hepatitis C virus genotypes 1a, 1b, 2, and 3a

Hepatitis C virus (HCV) infection affects millions of people and leads to liver fibrosis, cirrhosis, and hepatocellular carcinoma. Treatment regimen selection requires HCV genotype (Gt) and Gt 1 subtype determination. Use of a laboratory developed, reverse transcription (RT)-PCR assay was explored as a low-cost, high-throughput screening approach for the major HCV genotypes and subtypes in North America. A commercial line probe assay (LiPA) was used for comparison. Sequencing and/or an alternative PCR assay were used for discordant analyses. Testing of 155 clinical samples revealed that a paired, duplex real-time RT-PCR assay that targets Gts 1a and 3a in one reaction and Gts 1b and 2 in another had 95% overall sensitivity and individual Gt sensitivity and specificity of 98-100% and 85-98%, respectively. The RT-PCR assay detected mixed HCV Gts in clinical and spiked samples and no false-positive reactions occurred with rare Gts 3b, 4, 5, or 6. Implementation of the RT-PCR assay, with some reflex LiPA testing, would cost only a small portion of the cost of using LiPA alone, and can also save 1.5h of hands-on time. The use of a laboratory developed RT-PCR assay for HCV genotyping has the potential to reduce cost and labour burdens in high-volume testing settings.

The cost-effectiveness of testing for NS5a resistance-associated polymorphisms at baseline in genotype 1a-infected (treatment-naïve and treatment-experienced) subjects treated with all-oral elbasvir/grazoprevir regimens in the United States

BACKGROUND

The presence of baseline NS5A resistance-associated variants (RAVs) impacted treatment response in HCV genotype 1a (GT1a)-infected patients treated with elbasvir/grazoprevir (EBR/GZR) for 12 weeks, but not patients treated with EBR/GZR and ribavirin (RBV) for 16 weeks.

AIMS

To assess the cost-effectiveness of baseline testing for NS5A RAVs in EBR/GZR-treated patients compared without testing, and with current treatments for GT1a patients.

METHODS

We simulated the course of treatment with EBR/GZR, ledipasvir/sofosbuvir (LDV/SOF) and ombitasvir/paritaprevir/ritonavir+dasabuvir (3D) with or without RBV and natural history of disease of GT1a patients. Treatment-related data from clinical trials were used in a state-transition model of the natural history of chronic HCV GT1a infection and liver disease to project lifetime costs (US$2015) and quality-adjusted life years (QALY). Other clinical and economic inputs were estimated from published sources. We conducted base case and sensitivity analyses.

RESULTS

RAVs testing-guided treatment with EBR/GZR resulted in more QALYs than EBR/GZR without testing, 3D+RBV, or LDV/SOF8. This strategy was cost-saving relative to 3D+RBV or LDV/SOF8 and was cost-effective compared with EBR/GZR without testing. LDV/SOF12 was not cost-effective compared with the EBR/GZR RAVs testing-based strategy. Treatment with EBR/GZR guided by RAVs testing is the most effective regimen among treatment-experienced patients without cirrhosis and cirrhotic patients. In sensitivity analysis, RAVs testing was cost-effective in 48-55% and 63-85% among noncirrhotic and cirrhotic patients respectively.

CONCLUSIONS

RAVs testing before treatment with EBR/GZR is likely to be a cost-effective alternative to the use of EBR/GZR without testing, LDV/SOF, or 3D among GT1a treatment-naïve or treatment-experienced patients.

Hepatitis C virus genotype 4: Genotype 1's little brother

Treatment for hepatitis C virus genotype 4 infection has undergone a major advance over the past 5 years with the emergence of direct-acting antiviral agents. Previously, genotype 4 treatment had been limited to the combination of pegylated interferon and ribavirin, with low rates of sustained virological response. The combinations of new direct-acting agents have resulted in a radical improvement in hepatitis C therapy. Much of the currently available efficacy and safety information in the treatment of genotype 4 has been extrapolated through the results of genotype 1. In this report, we review the efficacy and safety data obtained in recent studies focusing on genotype 4 patients, including special populations, such as those with decompensated cirrhosis.

Molecular Testing in Emerging Infectious Diseases

It was widely believed in the late 1960s that infectious diseases had been conquered by vaccines and antibiotics and humans were no longer under threat by microbial pathogens. Yet, since that time more than 60 pathogens have been discovered that can cause serious emerging infectious diseases. Molecular methods have played critical roles in the discovery, monitoring, and clinical diagnostics of emerging pathogens. In this chapter, we present well-recognized emerging pathogens. We provide examples of the utility of molecular assays in research and clinical care of emerging infectious diseases. We also discuss some theoretical and practical limitations of molecular tests and the future prospects of expanding molecular diagnostics for emerging pathogens based on new advances of knowledge and technologies.

2015 Philip S. Portoghese Medicinal Chemistry Lectureship. Curing Hepatitis C Virus Infection with Direct-Acting Antiviral Agents: The Arc of a Medicinal Chemistry Triumph

The development of direct-acting antiviral agents that can cure a chronic hepatitis C virus (HCV) infection after 8-12 weeks of daily, well-tolerated therapy has revolutionized the treatment of this insidious disease. In this article, three of Bristol-Myers Squibb's HCV programs are summarized, each of which produced a clinical candidate: the NS3 protease inhibitor asunaprevir (64), marketed as Sunvepra, the NS5A replication complex inhibitor daclatasvir (117), marketed as Daklinza, and the allosteric NS5B polymerase inhibitor beclabuvir (142), which is in late stage clinical studies. A clinical study with 64 and 117 established for the first time that a chronic HCV infection could be cured by treatment with direct-acting antiviral agents alone in the absence of interferon. The development of small molecule HCV therapeutics, designed by medicinal chemists, has been hailed as "the arc of a medical triumph" but may equally well be described as "the arc of a medicinal chemistry triumph".

Hepatitis C Virus Genotype and Subtype Distribution in Patient Specimens Tested at the University of Texas Medical Branch, Galveston, Between January 2011 and November 2014

Hepatitis C virus (HCV) genotype/subtype data are routinely generated in clinical laboratories to guide treatment. Genotype data can also inform genotype distribution and molecular epidemiology of HCV infections in patient populations and geographical regions that clinics/laboratories serve. The aim of this study was to determine the distribution of HCV genotypes/subtypes and their association with demographic characteristics among the patients that were routinely tested in the Molecular Diagnostics Laboratory at The University of Texas Medical Branch (UTMB) at Galveston. Among the 6573 patients tested between January 2011 and November 2014, the most frequent HCV genotype/subtype was 1a (65.3%), followed by 3a (11.5%), 1b (10.4%), and 2b (8.8%). Combined, genotype 4 and genotype 6 were found in less than 1% of this cohort. Approximately 1.3% of the patients presented multiple genotypes/subtypes. Factors independently associated with genotypes and subtypes were race/ethnicity, sex, and patient age.

Genome-wide analysis for identification of adaptive diversification between hepatitis C virus subtypes 1a and 1b

Hepatitis C virus (HCV) is a major cause of liver disease and has been estimated to infect approximately 2%-3% of the world's population. HCV genotype 1 is the subject of intense research and clinical investigations because of its worldwide prevalence and poor access to treatment for patients in developing countries and marginalized populations. The predominant subtypes 1a and 1b of HCV genotype 1 present considerable differences in epidemiological features. However, the genetic signature underlying such phenotypic functional divergence is still an open question. Here, we performed a genome-wide evolutionary study on HCV subtypes 1a and 1b. The results show that adaptive selection has driven the diversification between these subtypes. Furthermore, the major adaptive divergence-related changes have occurred on proteins E1, NS4B, NS5A, and NS5B. Structurally, a number of adaptively selected sites cluster in functional regions potentially relevant to (i) membrane attachment and (ii) the interactions with viral and host cell factors and the genome template. These results might provide helpful hints about the molecular determinants of epidemiological divergence between HCV 1a and 1b.

Lower response to simeprevir and sofosbuvir in HCV genotype 1 in routine practice compared with clinical trials

BACKGROUND

High sustained virological response at 12 weeks after end of treatment (SVR12) with 12 weeks of simeprevir and sofosbuvir±ribavirin (SMV+SOF±RBV) has been demonstrated in hepatitis C virus genotype 1 (HCV-1) but is based on limited data. Therefore, we performed a meta-analysis of available data evaluating the effectiveness of SMV+SOF±RBV in HCV-1.

METHODS

We performed a comprehensive literature search in June 2015 to identify randomised controlled trials (RCTs) and observational studies of HCV-1 patients treated with 12 weeks of SMV+SOF±RBV. Original studies with SVR12 data in ≥5 HCV-1 patients were included. We excluded studies on liver transplant recipients and/or patients co-infected with HIV or hepatitis B/D. We estimated pooled effect sizes using a random-effects model and evaluated heterogeneity with Cochrane Q-test, p≤0.10 and I(2) statistic ≥50%.

RESULTS

Pooled SVR12 was 85.6% (CI 81.3% to 89.0%) in 1389 HCV-1 patients from 15 studies. On subgroup analysis, SVR12 was 83.9% (CI 79.4% to 87.5%) in observational studies, which was lower than 93.5% (CI 85.7% to 97.2%) in RCTs. A trend showed SVR12 was higher in mild fibrosis, 93.0% (CI 86.2% to 96.6%) compared with advanced fibrosis, 81.5% (CI 75.7% to 86.1%), OR 2.22 (CI 0.79 to 6.25, p=0.131). There was no significant difference in SVR12 rates between HCV-1a, 89.9% (CI 81.9% to 94.6%) and HCV-1b, 89.0% (CI 78.9% to 94.6%) with OR 1.35 (CI 0.75 to 2.42, p=0.322). The most common pooled side effects were: headache 15.2% (n=55/361), fatigue 12.1% (n=78/646), nausea 9.5% (n=50/527) and rash 9.3% (n=68/728).

CONCLUSIONS

SMV+SOF±RBV is an effective regimen in HCV-1 patients. The SVR12 rate in observational studies was lower than that in RCTs, which may reflect the more diverse patient population in real-world settings.

Analysis of HCV-6 isolates among Asian-born immigrants in North America reveals their high genetic diversity and a new subtype

We characterized full-length genomes for 15 HCV-6 isolates, all from Asian immigrants living in North America. Among these isolates, nine were novel variants showing >15% nucleotide differences from their nearest relatives, representing lineages distinct from known subtypes. The other six were classified into subtypes 6c, 6h, 6q, 6r, and 6s. The partial sequences were also determined for five additional HCV-6 isolates, three from the US and two from Canada. The latter two were assigned to new subtype 6xf as they were found to classify with two other isolates for which we recently reported their full-length genomes. We further analyzed partial Core-E1 sequences of 100 HCV-6 isolates sampled in North America, seven from the US and 93 from Canada and all from Asian immigrants except for four from Caucasians. These 100 isolates belonged to 20 assigned subtypes and 16 unclassified lineages showing great genetic diversity and enhanced significance to public health.

The Impact of Enhanced Screening and Treatment on Hepatitis C in the United States

BACKGROUND

The effectiveness of interferon-free direct-acting antivirals (DAA) in treating chronic hepatitis C virus (HCV) is limited by low screening and treatment rates, particularly among people who inject drugs (PWIDs).

METHODS

To evaluate the levels of screening and treatment with interferon-free DAAs that are required to control HCV incidence and HCV-associated morbidity and mortality, we developed a transmission model, stratified by age and by injection drug use, and calibrated it to epidemiological data in the United States from 1992 to 2014. We quantified the impact of administration of DAAs at current and at enhanced screening and treatment rates, focusing on outcomes of HCV incidence, prevalence, compensated and decompensated cirrhosis, hepatocellular carcinoma, liver transplants, and mortality from 2015 to 2040.

RESULTS

Increasing annual treatment of patients 4-fold-from the approximately 100 000 treated historically to 400 000-is predicted to prevent 526 084 (95% confidence interval, 466 615-593 347) cases of cirrhosis and 256 315 (201 589-316 114) HCV-associated deaths. By simultaneously increasing treatment capacity and increasing the number of HCV infections diagnosed, total HCV prevalence could fall to as low as 305 599 (222 955-422 110) infections by 2040. Complete elimination of HCV transmission in the United States through treatment with DAAs would require nearly universal screening of PWIDs, with an annual treatment rate of at least 30%.

CONCLUSIONS

Interferon-free DAAs are projected to achieve marked reductions in HCV-associated morbidity and mortality. Aggressive expansion in HCV screening and treatment, particularly among PWIDs, would be required to eliminate HCV in the United States.

Empirical fitness models for hepatitis C virus immunogen design

Hepatitis C virus (HCV) afflicts 170 million people worldwide, 2%-3% of the global population, and kills 350 000 each year. Prophylactic vaccination offers the most realistic and cost effective hope of controlling this epidemic in the developing world where expensive drug therapies are not available. Despite 20 years of research, the high mutability of the virus and lack of knowledge of what constitutes effective immune responses have impeded development of an effective vaccine. Coupling data mining of sequence databases with spin glass models from statistical physics, we have developed a computational approach to translate clinical sequence databases into empirical fitness landscapes quantifying the replicative capacity of the virus as a function of its amino acid sequence. These landscapes explicitly connect viral genotype to phenotypic fitness, and reveal vulnerable immunological targets within the viral proteome that can be exploited to rationally design vaccine immunogens. We have recovered the empirical fitness landscape for the HCV RNA-dependent RNA polymerase (protein NS5B) responsible for viral genome replication, and validated the predictions of our model by demonstrating excellent accord with experimental measurements and clinical observations. We have used our landscapes to perform exhaustive in silico screening of 16.8 million T-cell immunogen candidates to identify 86 optimal formulations. By reducing the search space of immunogen candidates by over five orders of magnitude, our approach can offer valuable savings in time, expense, and labor for experimental vaccine development and accelerate the search for a HCV vaccine.

ABBREVIATIONS

HCV-hepatitis C virus, HLA-human leukocyte antigen, CTL-cytotoxic T lymphocyte, NS5B-nonstructural protein 5B, MSA-multiple sequence alignment, PEG-IFN-pegylated interferon.

Cost-effectiveness of strategies for testing current hepatitis C virus infection

Six strategies for identifying hepatitis C virus (HCV) viremia, involving testing for HCV antibody (HCVAb) followed by a nucleic acid test (NAT) for HCV RNA when the antibody test is positive, are compared. Decision analysis was used to determine mean relative cost per person tested and outcomes of HCV viremia detection. Parameters included proportions of test population with HCVAb and viremia plus specificity, sensitivity, and cost of individual tests. For testing a population with an HCVAb seroprevalence of 3.25%, all strategies when adopting quantitative NAT vary little in cost (range, $29.50-$30.70) and are highly viremia specific (≥0.9997). Four of the strategies using venipuncture blood for HCVAb testing (whether laboratory conducted or employing a rapid, point-of-care assay) and for NAT (whether done by reflex or using separately drawn blood) achieve the highest viremia sensitivities (range, 0.9950-0.9954). Point-of-care HCVAb testing in fingerstick blood followed by NAT in venipuncture blood yields relatively lower viremia sensitivity (0.9301). The strategy that requires returning for NAT is even less viremia sensitive (<0.9000) because of follow-up loss. Strategies adopting qualitative rather than quantitative NAT are slightly cheaper (range, $28.90-$29.99), similarly viremia specific (≥0.9997), but less viremia sensitive (≤0.9456). Viremia sensitivity and specificity remain the same regardless of the proportion of HCVAb-seropositive persons in the cohort being tested.

CONCLUSIONS

Strategies involving HCVAb testing in venipuncture blood, whether laboratory conducted or using a point-of-care assay, when followed by quantitative NAT done reflexively or in separately drawn blood, are comparably economical and suitably viremia sensitive. Less cost-effective is point-of-care HCVAb testing in fingerstick blood followed by NAT in venipuncture blood. Least cost-effective is the strategy requiring the tested person to return for NAT.

Reuse of insulin pens among multiple patients at 2 Veterans Affairs medical centers

OBJECTIVE

To determine whether reuse of insulin pens among multiple patients resulted in transmission of bloodborne pathogens (BBP).

DESIGN

Retrospective cohort study.

SETTING

Two Veterans Affairs medical centers.

PATIENTS

Veterans who received insulin via insulin pens from 2010 to 2013. METHODS Patients were identified through electronic health records, notified of possible exposure, and serotested for human immunodeficiency virus, hepatitis C virus (HCV), and hepatitis B virus. Newly discovered case patients were assessed in relation to potential proximate patients to determine viral strain relatedness by HCV envelope (env) gene sequencing.

RESULTS

Of 1,791 hospitalized veterans who received insulin via insulin pen, 1,155 were tested for at least 1 viral infection after exposure. Of these, 67 patients were newly diagnosed with 1 or more viral BBPs. For human immunodeficiency virus and hepatitis B virus no additional strain testing of case or proximate patients was possible; 8 HCV cases and 45 proximates (40 unique patients; 5 patients were positive for 2 genotypes) were identified as needing strain testing. Only 3 cases and their 19 proximates had samples available for further testing. None of the 26 remaining proximate patients had blood available for further testing. Median genetic distance between the HCV env sequences of those available for additional testing ranged from 14% to 24%, indicating nonrelatedness.

CONCLUSIONS

Our investigation revealed that exposure to insulin pen reuse did not result in HCV transmission among patients who had viral genetic analysis performed. Analysis for any additional potential transmission of blood-borne pathogens was limited by the available samples.

The cost-effectiveness, health benefits, and financial costs of new antiviral treatments for hepatitis C virus

BACKGROUND

New hepatitis C virus (HCV) treatments deliver higher cure rates with fewer contraindications, increasing demand for treatment and healthcare costs. The cost-effectiveness of new treatments is unknown.

METHODS

We conducted a microsimulation of guideline testing followed by alternative treatment regimens for HCV among the US population aged 20 and older to estimate cases identified, treated, sustained viral response, deaths, medical costs, quality-adjusted life-years (QALYs), and the incremental cost-effectiveness ratio (ICER) of different treatment options expressed as discounted lifetime costs and benefits from the healthcare perspective.

RESULTS

Compared to treatment with pegylated interferon and ribavirin (PR), and a protease inhibitor for HCV genotype (G) 1 and PR alone for G2/3, treatment with PR and Sofosbuvir (PRS) for G1/4 and treatment with Sofosbuvir and ribavirin (SR) for G2/3 increased QALYs by 555 226, reduced deaths by 80 682, and increased costs by $26.2 billion at an ICER of $47 304 per QALY gained. As compared to PRS/SR, treating with an all oral regimen of Sofosbuvir and Simeprevir (SS) for G1/4 and SR for G2/3, increased QALYs by 1 110 451 and reduced deaths by an additional 164 540 at an incremental cost of $80.1 billion and an ICER of $72 169. In sensitivity analysis, where treatment with SS effectiveness was set to the list price of Viekira Pak and then Harvoni, treatment cost $24 921 and $25 405 per QALY gained as compared to PRS/SR.

CONCLUSIONS

New treatments are cost-effectiveness per person treated, but pent-up demand for treatment may create challenges for financing.

Cutaneous Adverse Events in Chronic Hepatitis C Patients Treated With New Direct-Acting Antivirals

Background:

Direct-acting antivirals (DAAs) are known to present with additional dermatological events over pegylated-interferon/ribavirin (Peg-IFN/RBV).

Objective:

A systematic review and meta-analysis was conducted to assess the incidence/risk of cutaneous adverse events (AEs) for simeprevir, sofosbuvir, ABT450/r-ombitasvir, dasabuvir, ledipasvir, daclatasvir, and asunaprevir.

Methods:

The databases searched included PubMed, Clinicaltrials.gov, and Clinicaloptions.com. Data on telaprevir and boceprevir were obtained from a previous study.

Results:

The incidences of cutaneous AEs were 34.3% (95% CI 18.4%-54.8%) for the old DAAs + Peg-IFN/RBV, 22.0% (95% CI 17.9%-26.8%) for the new DAAs + Peg-IFN/RBV, 9.8% (95% CI 8.6%-11.2%) for the DAAs + RBV, and 3.8% (95% CI 2.4%-6.1%) for DAAs only. Simeprevir + Peg-IFN/RBV was associated with an increased relative risk over Peg-IFN/RBV; RR = 1.319 (95% CI 1.026-1.697).

Conclusion:

Dermatological events are still an important issue for many of the new DAAs. Appropriate monitoring, management, and patient education are needed to minimize AEs and achieve HCV cure.

The combination of simeprevir and sofosbuvir is more effective than that of peginterferon, ribavirin, and sofosbuvir for patients with hepatitis C-related Child's class A cirrhosis

BACKGROUND & AIMS

The efficacy and safety of interferon-free regimens for the treatment of chronic hepatitis C virus (HCV) infections require further evaluation and comparison with those of interferon-containing regimens. We compared a regimen of peginterferon, ribavirin, and sofosbuvir with a regimen of simeprevir and sofosbuvir in patients with HCV infection and unfavorable treatment features.

METHODS

We performed a prospective open-label study of 82 patients with chronic HCV genotype 1a infection and Child's grade A cirrhosis enrolled from 2 clinics at a single center in Atlanta, Georgia, from December 2013 through January 2014. Fifty patients (61%) had not responded to treatment with peginterferon and ribavirin (null responders), and 32 (39%) were therapy naive; 39 (48%) were African American. Subjects were assigned randomly to groups given simeprevir (150 mg/day) and sofosbuvir (400 mg/day) (n = 58 in the final analysis) or peginterferon alfa 2b (1.5 mcg/kg/wk), ribavirin (1000-1200 mg/day), and sofosbuvir (400 mg/day) (n = 24 in the final analysis). Both regimens were given for 12 weeks. The primary trial end point was the proportion of patients with undetectable HCV-RNA levels 12 weeks after therapy completion (SVR12).

RESULTS

A significantly greater percentage of patients (93%) given simeprevir and sofosbuvir achieved an SVR12 than those given the interferon-containing regimen (75%) (P = .02). Patients given the interferon-containing regimen had a significantly higher rate of virologic relapse than patients given simeprevir and sofosbuvir (P = .009), as well as worse self-reported outcomes and more side effects. Quality-of-life scores were higher in patients with SVR12 than those without, regardless of treatment regimen.

CONCLUSIONS

In a prospective study of patients with chronic HCV genotype 1a infection and cirrhosis (48% African American and 61% prior null responders), a 12-week regimen of simeprevir and sofosbuvir produced a significantly higher rate of SVR12 and was better tolerated, with a lower viral relapse rate, than a 12-week regimen of peginterferon, ribavirin, and sofosbuvir. Clinicaltrials.gov no: NCT021683615.

6-(Azaindol-2-yl)pyridine-3-sulfonamides as potent and selective inhibitors targeting hepatitis C virus NS4B

A structure-activity relationship investigation of various 6-(azaindol-2-yl)pyridine-3-sulfonamides using the HCV replicon cell culture assay led to the identification of a potent series of 7-azaindoles that target the hepatitis C virus NS4B. Compound 2ac, identified via further optimization of the series, has excellent potency against the HCV 1b replicon with an EC50 of 2nM and a selectivity index of >5000 with respect to cellular GAPDH RNA. Compound 2ac also has excellent oral plasma exposure levels in rats, dogs and monkeys and has a favorable liver to plasma distribution profile in rats.

Results from a Large-Scale Epidemiologic Look-Back Investigation of Improperly Reprocessed Endoscopy Equipment

Objective.

To determine whether improper high-level disinfection practices during endoscopy procedures resulted in bloodborne viral infection transmission.

Design.

Retrospective cohort study.

Setting.

Four Veterans Affairs medical centers (VAMCs).

Patients.

Veterans who underwent colonoscopy and laryngoscopy (ear, nose, and throat [ENT]) procedures from 2003 to 2009.

Methods.

Patients were identified through electronic health record searches and serotested for human immunodeficiency virus (HIV), hepatitis C virus (HCV), and hepatitis B virus (HBV). Newly discovered case patients were linked to a potential source with known identical infection, whose procedure occurred no more than 1 day prior to the case patient's procedure. Viral genetic testing was performed for case/proximate pairs to determine relatedness.

Results.

Of 10,737 veterans who underwent endoscopy at 4 VAMCs, 9,879 patients agreed to viral testing. Of these, 90 patients were newly diagnosed with 1 or more viral bloodborne pathogens (BBPs). There were no case/proximate pairings found for patients with either HIV or HBV; 24 HCV case/proximate pairings were found, of which 7 case patients and 8 proximate patients had sufficient viral load for further genetic testing. Only 2 of these cases, both of whom underwent laryngoscopy, and their 4 proximates agreed to further testing. None of the 4 remaining proximate patients who underwent colonoscopy agreed to further testing. Mean genetic distance between the 2 case patients and 4 proximate patients ranged from 13.5% to 19.1%.

Conclusions.

Our investigation revealed that exposure to improperly reprocessed ENT endoscopes did not result in viral transmission in those patients who had viral genetic analysis performed. Any potential transmission of BBPs from colonoscopy remains unknown.

Results from a Large-Scale Epidemiologic Look-Back Investigation of Improperly Reprocessed Endoscopy Equipment

Objective.

To determine whether improper high-level disinfection practices during endoscopy procedures resulted in bloodborne viral infection transmission.

Design.

Retrospective cohort study.

Setting.

Four Veterans Affairs medical centers (VAMCs).

Patients.

Veterans who underwent colonoscopy and laryngoscopy (ear, nose, and throat [ENT]) procedures from 2003 to 2009.

Methods.

Patients were identified through electronic health record searches and serotested for human immunodeficiency virus (HIV), hepatitis C virus (HCV), and hepatitis B virus (HBV). Newly discovered case patients were linked to a potential source with known identical infection, whose procedure occurred no more than 1 day prior to the case patient's procedure. Viral genetic testing was performed for case/proximate pairs to determine relatedness.

Results.

Of 10,737 veterans who underwent endoscopy at 4 VAMCs, 9,879 patients agreed to viral testing. Of these, 90 patients were newly diagnosed with 1 or more viral bloodborne pathogens (BBPs). There were no case/proximate pairings found for patients with either HIV or HBV; 24 HCV case/proximate pairings were found, of which 7 case patients and 8 proximate patients had sufficient viral load for further genetic testing. Only 2 of these cases, both of whom underwent laryngoscopy, and their 4 proximates agreed to further testing. None of the 4 remaining proximate patients who underwent colonoscopy agreed to further testing. Mean genetic distance between the 2 case patients and 4 proximate patients ranged from 13.5% to 19.1%.

Conclusions.

Our investigation revealed that exposure to improperly reprocessed ENT endoscopes did not result in viral transmission in those patients who had viral genetic analysis performed. Any potential transmission of BBPs from colonoscopy remains unknown.

Provision of clinical pharmacist services for individuals with chronic hepatitis C viral infection: Joint Opinion of the GI/Liver/Nutrition and Infectious Diseases Practice and Research Networks of the American College of Clinical Pharmacy

The objective of this opinion paper was to identify and describe potential clinical pharmacists' services for the prevention and management of patients infected with the hepatitis C virus (HCV). The goals of this paper are to guide the establishment and development of pharmacy services for patients infected with HCV and to highlight HCV research and educational opportunities. Recommendations were based on the following: a review of published data on clinical pharmacist involvement in the treatment and management of HCV-infected patients; a consensus of clinical pharmacists who provide direct patient care to HCV-infected patients and practice in different pharmacy models, including community-based and academic settings; and a review of published guidelines and literature focusing on the treatment and management of HCV infections. The recommendations provided in this opinion paper define the areas of clinical pharmacist involvement and clinical pharmacy practice in the treatment and management of patients with HCV. Clinical pharmacists can promote preventive measures and education about reducing HCV transmission, improve medication adherence, assist in monitoring clinical and adverse effects, recommend treatment strategies to minimize adverse effects and drug interactions, and facilitate medication acquisition and logistics that positively improve patient outcomes and reduce the health care system costs.

The genetic diversity and evolutionary history of hepatitis C virus in Vietnam

Vietnam has a unique history in association with foreign countries, which may have resulted in multiple introductions of the alien HCV strains to mix with those indigenous ones. In this study, we characterized the HCV sequences in Core-E1 and NS5B regions from 236 Vietnamese individuals. We identified multiple HCV lineages; 6a, 6 e, 6h, 6k, 6l, 6 o, 6p, and two novel variants may represent the indigenous strains; 1a was probably introduced from the US; 1b and 2a possibly originated in East Asia; while 2i, 2j, and 2m were likely brought by French explorers. We inferred the evolutionary history for four major subtypes: 1a, 1b, 6a, and 6 e. The obtained Bayesian Skyline Plots (BSPs) consistently showed the rapid HCV population growth from 1955 to 1963 until 1984 or after, corresponding to the era of the Vietnam War. We also estimated HCV growth rates and reconstructed phylogeographic trees for comparing subtypes 1a, 1b, and HCV-2.

Recent population expansions of hepatitis B virus in the United States

The recent epidemic history of hepatitis B virus (HBV) infections in the United States is complex, as indicated by current disparity in HBV genotype distribution between acute and chronic hepatitis B cases and the rapid decline in hepatitis B incidence since the 1990s. We report temporal changes in the genetic composition of the HBV population using whole-genome sequences (n = 179) from acute hepatitis B cases (n = 1,206) identified through the Sentinel County Surveillance for Acute Hepatitis (1998 to 2006). HBV belonged mainly to subtypes A2 (75%) and D3 (18%), with times of their most recent common ancestors being 1979 and 1987, respectively. A2 underwent rapid population expansions in ca. 1995 and ca. 2002, coinciding with transient rises in acute hepatitis B notification rates among adults; D3 underwent expansion in ca. 1998. A2 strains from cases identified after 2002, compared to those before 2002, tended to cluster phylogenetically, indicating selective expansion of specific strains, and were significantly reduced in genetic diversity (P = 0.001) and frequency of drug resistance mutations (P = 0.001). The expansion of genetically close HBV A2 strains was associated with risk of infection among male homosexuals (P = 0.03). Incident HBV strains circulating in the United States were recent in origin and restricted in genetic diversity. Disparate transmission dynamics among phylogenetic lineages affected the genetic composition of HBV populations and their capacity to maintain drug resistance mutations. The tendency of selectively expanding HBV strains to be transmitted among male homosexuals highlights the need to improve hepatitis B vaccination coverage among at-risk adults.

IMPORTANCE

Hepatitis B virus (HBV) remains an important cause of acute and chronic liver disease globally and in the United States. Genetic analysis of HBV whole genomes from cases of acute hepatitis B identified from 1998 to 2006 in the United States showed dominance of genotype A2 (75%), followed by D3 (18%). Strains of both subtypes were recent in origin and underwent rapid population expansions from 1995 to 2000, indicating increase in transmission rate for certain HBV strains during a period of decline in the reported incidence of acute hepatitis B in the United States. HBV A2 strains from a particular cluster that experienced the most recent population expansion were more commonly detected among men who have sex with men. Vaccination needs to be stepped up to protect persons who remain at risk of HBV infection.