Personalized cost-effectiveness of boceprevir-based triple therapy for untreated patients with genotype 1 chronic hepatitis C

System dynamics simulation for evaluating implementation strategies of genomic sequencing: tutorial and conceptual model

INTRODUCTION

Precision Medicine (PM), especially in oncology, involve diagnostic and complex treatment pathways that are based on genomic features. To conduct evaluation and decision analysis for PM, advanced modeling techniques are needed due to its complexity. Although System Dynamics (SD) has strong modeling power, it has not been widely used in PM and individualized treatment.

AREAS COVERED

We explained SD tools using examples in cancer context and the rationale behind using SD for genomic testing and personalized oncology. We compared SD with other Dynamic Simulation Modelling (DSM) methods and listed SD's advantages. We developed a conceptual model using Causal Loop Diagram (CLD) for strategic decision-making in Whole Genome Sequencing (WGS) implementation.

EXPERT OPINION

The paper demonstrates that SD is well-suited for health policy evaluation challenges and has useful tools for modeling precision oncology and genomic testing. SD's system-oriented modeling captures dynamic and complex interactions within systems using feedback loops. SD models are simple to implement, utilize less data and computational resources, and conduct both exploratory and explanatory analyses over time. If the targeted system has complex interactions and many components, deals with lack of data, and requires interpretability and clinicians' input, SD offers attractive advantages for modeling and evaluating scenarios.

Predicting Treatment Failure for Initiators of Hepatitis C Virus Treatment in the era of Direct-Acting Antiviral Therapy

Introduction: Hepatitis C virus (HCV), the leading cause of advanced liver disease, has enormous economic burden. Identification of patients at risk of treatment failure could lead to interventions that improve cure rates.

Objectives: Our goal was to develop and evaluate a prediction model for HCV treatment failure.

Methods: We analyzed HCV patients initiating direct-acting antiviral therapy at four United States institutions. Treatment failure was determined by lack of sustained virologic response (SVR) 12 weeks after treatment completion. From 20 patient-level variables collected before treatment initiation, we identified a subset associated with treatment failure in bivariate analyses. In a derivation set, separate predictive models were developed from 100 bootstrap samples using logistic regression. From the 100 models, variables were ranked by frequency of selection as predictors to create four final candidate models, using cutoffs of ≥80%, ≥50%, ≥40%, and all variables. In a validation set, predictive performance was compared across models using area under the receiver operating characteristic curve.

Results: In 1,253 HCV patients, overall SVR rate was 86.1% (95% CI = 84.1%, 88.0%). The AUCs of the four final candidate models were: ≥80% = 0.576; ≥50% = 0.605; ≥40% = 0.684; all = 0.681. The best performing model (≥40%) had significantly better predictive ability than the ≥50% (p = 0.03) and ≥80% models (p = 0.02). Strongest predictors of treatment failure were older age, history of hepatocellular carcinoma, and private (vs. government) insurance.

Conclusion: This study highlighted baseline factors associated with HCV treatment failure. Treatment failure prediction may facilitate development of data-driven clinical tools to identify patients who would benefit from interventions to improve SVR rates.

Cost-effectiveness of second-generation direct-acting antiviral agents in chronic HCV infection: a systematic literature review

BACKGROUND

Our objectives were to review the economic modelling methods and cost-effectiveness of second-generation direct-acting antiviral agents for the treatment of chronic HCV infection.

METHODS

A systematic literature search was performed in February 2017 using Scopus and OVID to review relevant publications between 2011 to present. Two independent reviewers screened potential papers.

RESULTS

The database search resulted in a total of 1,536 articles; after deduplication, title/abstract and full text screening, 67 studies were included for qualitative analysis. The vast majority of studies were conducted in high-income countries (n=59) and used Markov-based modelling techniques (n=60). Most of the analyses utilized long-term time horizons; 58 studies calculated lifetime costs and outcomes. The examined treatments were heterogenic among the studies; seven analyses did not directly evaluate treatments (just with screening or genotype testing). The examined treatments (n=60) were either dominant (23%), or cost-effective at base case (57%) or in given subgroups (18%). Only one (2%) study reported that the assessed treatment was not cost-effective with the given setting and price.

CONCLUSIONS

Despite their high initial therapeutic costs, second-generation direct-acting antiviral agents were found to be cost-effective to treat chronic HCV infection. Studies were predominantly conducted in higher income countries, although we have limited information on cost-effectiveness in low- and middle-income countries, where assessment of cost-effectiveness is even more essential due to more limited health-care resources and potentially higher public health burden due to unsafe medical interventions.

Cost-effectiveness of diagnostic and therapeutic interventions for chronic hepatitis C: a systematic review of model-based analyses

BACKGROUND

Decisions about which subgroup of chronic hepatitis C (CHC) patients should be treated with direct acting anti-viral agents (DAAs) have economic importance due to high drug prices. Treat-all DAA strategies for CHC have gained acceptance despite high drug acquisition costs. However, there are also costs associated with the surveillance of CHC to determine a subgroup of patients with significant impairment. The aim of this systematic review was to describe the modelling methods used and summarise results in cost-effectiveness analyses (CEAs) of both CHC treatment with DAAs and surveillance of liver disease.

METHODS

Electronic databases including Embase and Medline were searched from inception to May 2015. Eligible studies included models predicting costs and/or outcomes for interventions, surveillance, or management of people with CHC. Narrative and quantitative synthesis were conducted. Quality appraisal was conducted using validated checklists. The review was conducted following principles published by NHS Centre for Research and Dissemination.

RESULTS

Forty-one CEAs met the eligibility criteria for the review; 37 evaluated an intervention and four evaluated surveillance strategies for targeting DAA treatment to those likely to gain most benefit. Included studies were of variable quality mostly due to reporting omissions. Of the 37 CEAs, eight models that enabled comparative analysis were fully appraised and synthesized. These models provided non-unique cost-effectiveness estimates in a specific DAA comparison in a specific population defined in terms of genotype, prior treatment status, and presence or absence of cirrhosis. Marked heterogeneity in cost-effectiveness estimates was observed despite this stratification. Approximately half of the estimates suggested that DAAs were cost-effective considering a threshold of US$30,000 and 73% with threshold of US$50,000. Two models evaluating surveillance strategies suggested that treating all CHC patients regardless of the staging of liver disease could be cost-effective.

CONCLUSIONS

CEAs of CHC treatments need to better account for variability in their estimates. This analysis suggested that there are still circumstances where DAAs are not cost-effective. Surveillance in place of a treat-all strategy may still need to be considered as an option for deploying DAAs, particularly where acquisition cost is at the limit of affordability for a given health system.

Hepatitis C Treatment Regimens Are Cost-Effective: But Compared With What?

BACKGROUND

Numerous economic models have been published evaluating treatment of chronic hepatitis C virus (HCV) infection, but none provide a comprehensive comparison among new antiviral agents.

OBJECTIVE

Evaluate the cost-effectiveness of all recommended therapies for treatment of genotypes 1 and 4 chronic HCV.

METHODS

Using data from clinical trials, observational analyses, and drug pricing databases, Markov decision models were developed for HCV genotypes 1 and 4 to compare all recommended drugs from the perspective of the third-party payer over a 5-, 10-, and 50-year time horizon. A probabilistic sensitivity analysis (PSA) was conducted by assigning distributions for clinical cure, age entering the model, costs for each health state, and quality-adjusted life years (QALYs) for each health state in a Monte Carlo simulation of 10 000 repetitions of the model.

RESULTS

In the lifetime model for genotype 1, effects ranged from 18.08 to 18.40 QALYs and total costs ranged from $88 107 to $184 636. The lifetime model of genotype 4 treatments had a range of effects from 18.23 to 18.43 QALYs and total costs ranging from $87 063 to $127 637. Grazoprevir/elbasvir was the optimal strategy followed by velpatasvir/sofosbuvir as the second-best strategy in most simulations for both genotypes 1 and 4, with drug costs and efficacy of grazoprevir/elbasvir as the primary model drivers.

CONCLUSIONS

Grazoprevir/elbasvir was cost-effective compared with all strategies for genotypes 1 and 4. Effects for all strategies were similar with cost of drug in the initial year driving the results.

Effectiveness of triple therapy with direct-acting antivirals for hepatitis C genotype 1 infection: application of propensity score matching in a national HCV treatment registry

Background

Observational studies are used to measure the effectiveness of an intervention in non-experimental, real world scenarios at the population level and are recognised as an important component of the evidence pyramid. Such data can be accrued through prospective cohort studies and a patient registry is a proven method for this type of study. The national hepatitis C (HCV) registry was established in Ireland in 2012 with the aim of monitoring the clinical and economic outcomes from new, high cost regimens for the treatment of HCV infection. A sustained virological response (SVR) 24 weeks following completion of therapy with interferon-containing regimens is considered a cure. Non-randomisation in these studies can result in confounding or selection bias. Propensity score (PS) matching is one of a number of statistical tools that can be used to mitigate the effects of confounding in observational studies.

Methods

We analysed the data of 309 patients who underwent triple therapy treatment with telaprevir (TPV) in combination with pegylated-interferon and ribavirin (PR) or boceprevir (BOC)/PR between June 2012 and December 2014. The decision to initiate treatment and the selection of the treatment regimen was at the discretion of the physician. To adjust for confounding, three approaches to propensity score matching were assessed Adjusted sustained-virological response rates (SVR), odds ratios, p-values and 95% confidence intervals were calculated from the three PS matched dataset.

Results

Prior to matching, the unadjusted sustained virological response rates 24 weeks after treatment complete (SVR24) were 74% (n = 158/215) and 61% (n = 57/94) for telaprevir/PR and boceprevir/PR, respectively. After matching, adjusted SVR24 rates were between 73–74% and 60–61% for telaprevir/PR and boceprevir/PR, respectively.

Conclusion

Efficacy rates were comparable with those reported in pivotal clinical trials and real world studies. After adjusting for confounding, we conclude that there was no difference in treatment effect after PS matching. The small sample size limits the conclusions that can be made about the effect of PS matching. Propensity score adjustment remains a tool that can be applied to future analysis, however, we suggest, where possible, using a larger sample size in order to reduce the uncertainty around the outcomes.

Electronic supplementary material

The online version of this article (doi:10.1186/s12913-017-2188-1) contains supplementary material, which is available to authorized users.

Optimizing choice of oral interferon-free treatment for genotype 1 hepatitis C virus using testing for NS5A resistance: a cost-utility analysis from the perspective of the Italian National Health Service

BACKGROUND

Patients with genotype-1 hepatitis C virus infection who have failed to respond to standard therapy or who relapse following treatment may be considered for an interferon-free regimen incorporating a nonstructural protein 5A (NS5A) inhibitor. Sustained virologic response (SVR) with these regimens is typically >90%, but this is reduced in patients with NS5A resistance. European Association for Study of the Liver guidelines recommend simeprevir + sofosbuvir ± ribavirin (SMV+SOF±R) for re-treating patients failing an NS5A inhibitor-containing regimen. An alternative strategy would be to test for NS5A resistance prior to treatment, with therapy optimized based on the results. This study investigates the cost-effectiveness of this strategy.

MATERIALS AND METHODS

A Markov model was used to estimate disease progression for treatment-experienced genotype 1 patients with severe fibrosis or compensated cirrhosis. Targeted treatment with either SMV+SOF±R or sofosbuvir + ledipasvir ± ribavirin (SOF+LDV±R) based on pretreatment NS5A resistance testing was compared to routine SOF+LDV±R without testing. Treatment duration was 12 or 24 weeks for patients with severe fibrosis or compensated cirrhosis (Metavir F3/F4). SVR data for the treatment options were based on the results of published clinical trials. The analysis was carried out from the perspective of the Italian National Health Service.

RESULTS

Optimized treatment using NS5A resistance testing yielded 0.163 additional QALYs and increased costs of €2,789 per patient versus no testing. The incremental cost-effectiveness ratio (ICER) was €17,078/QALY. Sensitivity analysis identified the SVR attributable to each of the treatment regimens as the most sensitive determinant of ICER (range: €10,055/QALY-€43,501/QALY across plausible range). Probabilistic sensitivity analysis demonstrated that, at a willingness-to-pay threshold of €30,000/QALY, the probability that NS5A-directed treatment will be cost-effective is 81.4%.

CONCLUSION

Optimizing therapy with either SMV+SOF±R or SOF+LDV±R based on pretreatment NS5A resistance testing was cost-effective from the perspective of the Italian National Health Service, in treatment-experienced patients with severe fibrosis or compensated cirrhosis.

Assessing the Effect of Potential Reductions in Non-Hepatic Mortality on the Estimated Cost-Effectiveness of Hepatitis C Treatment in Early Stages of Liver Disease

BACKGROUND

Most cost-effectiveness analyses of hepatitis C (HCV) therapy focus on the benefits of reducing liver-related morbidity and mortality.

OBJECTIVES

Our objective was to assess how cost-effectiveness estimates of HCV therapy can vary depending on assumptions regarding the potential impact of HCV therapy on non-hepatic mortality.

METHODS

We adapted a state-transition model to include potential effects of HCV therapy on non-hepatic mortality. We assumed successful treatment could reduce non-hepatic mortality by as little as 0 % to as much as 100 %. Incremental cost-effectiveness ratios were computed comparing immediate treatment versus delayed treatment and comparing immediate treatment versus non-treatment.

RESULTS

Comparing immediate treatment versus delayed treatment, when we included a 44 % reduction in non-hepatic mortality following successful HCV treatment, the incremental cost per quality-adjusted life year (QALY) gained by HCV treatment fell by 76 % (from US$314,100 to US$76,900) for patients with no fibrosis and by 43 % (from US$62,500 to US$35,800) for patients with moderate fibrosis. Comparing immediate treatment versus non-treatment, assuming a 44 % reduction in non-hepatic mortality following successful HCV treatment, the incremental cost per QALY gained by HCV treatment fell by 64 % (from US$186,700 to US$67,300) for patients with no fibrosis and by 27 % (from US$35,000 to US$25,500) for patients with moderate fibrosis.

CONCLUSION

Including reductions in non-hepatic mortality from HCV treatment can have substantial effects on the estimated cost-effectiveness of treatment.

A systematic review and checklist presenting the main challenges for health economic modeling in personalized medicine: towards implementing patient-level models

INTRODUCTION

The ongoing development of genomic medicine and the use of molecular and imaging markers in personalized medicine (PM) has arguably challenged the field of health economic modeling (HEM). This study aims to provide detailed insights into the current status of HEM in PM, in order to identify if and how modeling methods are used to address the challenges described in literature. Areas covered: A review was performed on studies that simulate health economic outcomes for personalized clinical pathways. Decision tree modeling and Markov modeling were the most observed methods. Not all identified challenges were frequently found, challenges regarding companion diagnostics, diagnostic performance, and evidence gaps were most often found. However, the extent to which challenges were addressed varied considerably between studies. Expert commentary: Challenges for HEM in PM are not yet routinely addressed which may indicate that either (1) their impact is less severe than expected, (2) they are hard to address and therefore not managed appropriately, or (3) HEM in PM is still in an early stage. As evidence on the impact of these challenges is still lacking, we believe that more concrete examples are needed to illustrate the identified challenges and to demonstrate methods to handle them.

Value of Treating All Stages of Chronic Hepatitis C: A Comprehensive Review of Clinical and Economic Evidence

INTRODUCTION

The goal of chronic hepatitis C (CHC) treatment is to achieve a sustained virologic response (SVR). The new generation of direct-acting antivirals (DAAs) offers 90-100% SVR rates. However, access to these treatments is generally limited to patients with advanced liver disease. The aim of this review is to provide an overview of the clinical and economic benefits of achieving SVR and to better understand the full value of CHC treatment in all stages of liver disease.

METHODS

A comprehensive literature review was performed using the PubMed, Embase, and Cochrane library databases to identify articles examining the clinical, economic, and quality of life benefits associated with SVR. Articles were limited to those published in English language from January 2006 through January 2016. Inclusion criteria were (1) patients with CHC, (2) retrospective and prospective studies, (3) reporting of mortality, liver morbidity, extrahepatic manifestations (EHMs), and economic outcomes and, (4) availability of an abstract or full-text publication.

RESULTS

Overall this review identified 354 studies involving more than 500,000 CHC patients worldwide. Evidence from 38 studies (n = 73,861) shows a significant mortality benefit of achieving SVR in patients with all stages of fibrosis. Long-term studies with follow-up of 5-12 years suggest that, particularly among non-cirrhotic patients, there is a significant decrease in mortality in SVR versus non-SVR groups. Ninety-nine studies conducted in 235,891 CHC patients in all stages of fibrosis show that SVR reduces liver-related mortality, incidence of hepatocellular carcinoma (HCC), and decompensation. A total of 233 studies show that chronic HCV infection is associated with several serious EHMs, some of which can have high mortality. Evidence from four modeling studies shows that delaying treatment to CHC patient populations could significantly increase mortality, morbidity, and medical costs.

CONCLUSIONS

There is a robust body of evidence demonstrating diverse sources of value from achieving SVR in all stages of liver disease. While access to treatment is generally limited to late-stage patients, less restrictive treatment strategies that target HCV eradication have the potential to abate the burdens of mortality, liver morbidity and extrahepatic manifestations, and the associated healthcare costs.

Systematic Review of Modelling Approaches for the Cost Effectiveness of Hepatitis C Treatment with Direct-Acting Antivirals

BACKGROUND

New direct-acting antivirals (DAAs) are highly effective for hepatitis C virus (HCV) treatment. However, their prices have been widely debated. Decision-analytic models can project the long-term value of HCV treatment. Therefore, understanding of the methods used in these models and how they could influence results is important.

OBJECTIVE

Our objective was to describe and systematically review the methodological approaches in published cost-effectiveness models of chronic HCV treatment with DAAs.

DATA SOURCES

We searched several electronic databases, including Medline, Embase and EconLit, from 2011 to 2015.

STUDY ELIGIBILITY

Study selection was performed by two reviewers independently. We included any cost-effectiveness analysis comparing DAAs with the old standard of care for HCV treatment. We excluded non-English-language studies and studies not reporting quality-adjusted life-years.

STUDY APPRAISAL AND SYNTHESIS METHOD

One reviewer collected data and assessed the quality of reporting, using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement. Another reviewer crosschecked the abstracted information. The development methods of the included studies were synthetized on the basis of good modelling practice recommendations.

RESULTS

Review of 304 citations revealed 36 cost-effectiveness analyses. The reporting quality scores of most articles were rated as acceptable, between 67 and 100 %. The majority of the studies were conducted in Europe (50 %), followed by the USA (44 %). Fifty-six percent of the 36 studies evaluated the cost effectiveness of HCV treatment in both treatment-naive and treatment-experienced patients, 97 % included genotype 1 patients and 53 % evaluated the cost effectiveness of second-generation or oral DAAs in comparison with the previous standard of care or other DAAs. Twenty-one models defined health states in terms of METAVIR fibrosis scores. Only one study used a discrete-event simulation approach, and the remainder used state-transition models. The time horizons varied; however, 89 % of studies used a lifetime horizon. One study was conducted from a societal perspective. Thirty-three percent of studies did not conduct any model validation. We also noted that none of the studies modelled HCV treatment as a prevention strategy, 86 % of models did not consider the possibility of re-infection with HCV after successful treatment, 97 % of studies did not consider indirect economic benefits resulting from HCV treatment and none of the studies evaluating oral DAAs used real-world data.

LIMITATIONS

The search was limited by date (from 1 January 2011 to 8 September 2015) and was also limited to English-language and published reports.

CONCLUSIONS

Most modelling studies used a similar modelling structure and could have underestimated the value of HCV treatment. Future modelling efforts should consider the benefits of HCV treatment in preventing transmission, extra-hepatic and indirect economic benefits of HCV treatment, real-world cost-effectiveness analysis and cost effectiveness of HCV treatment in low- and middle-income countries.

Duplex High-Resolution Melting Assay for the Simultaneous Genotyping of IL28B rs12979860 and PNPLA3 rs738409 Polymorphisms in Chronic Hepatitis C Patients

Chronic hepatitis C (CHC) is a major burden for public health worldwide. Although newer direct-acting antivirals show good efficacy, their cost precludes their wide adoption in resource-limited regions. Thus, strategies are being developed to help identify patients with high susceptibility to response to classic PEG-interferon + ribavirin therapy. IL28B polymorphism rs12979860 C/T is an important predictor for an efficient response to interferon-based therapy. A genetic variant in adiponutrin (PNPLA3) gene, rs738409 C/G, is associated with steatosis, severity, and progression of liver fibrosis in CHC patients, and predicts treatment outcome in difficult-to-cure HCV-infected patients with advanced fibrosis. We developed a rapid and inexpensive assay based on duplex high-resolution melting (HRM) for the simultaneous genotyping of these two polymorphisms. The assay validation was performed on synthetic DNA templates and 132 clinical samples from CHC patients. When compared with allele-specific PCR and sequencing, our assay showed 100% (95% CI: 0.9724-1) accuracy, with 100% sensitivity and specificity. Our assay was robust against concentration and quality of DNA samples, melting curve normalization intervals, HRM analysis algorithm, and sequence variations near the targeted SNPs (single nucleotide polymorphism). This duplex assay should provide useful information for patient-oriented management and clinical decision-making in CHC.

HCV: the best cure possible or the best possible cure?

Progress in medicine goes along with an exponential growth of the cost of drugs and devices. While any person has the right to obtain the best possible benefit from medical care, a state needs to strike a balance between granting the optimal personal benefit to each individual and the needs of the society as a whole. Health systems in all countries therefore are facing a huge problem of distributive justice, as while they should guarantee individual rights, among which the right to health in its broader sense, including physical, psychological and social well-being (therefore not limited to healing, but extending to compliance and quality of life), they must also grant equal access to the healthcare resources and keep the distribution system sustainable.

Outcomes, costs and cost-effectiveness of treating hepatitis C with direct acting antivirals

Hepatitis C is a global public health burden. Long-term consequences are the development of liver cirrhosis and hepatocellular carcinoma. Introduction of different direct acting antivirals targeting the hepatitis C proteins has considerably increased rates of sustained viral response. First active substances introduced in 2011 were NS3/4A protease inhibitors telaprevir and boceprevir. In 2013/2014 the second generation of direct acting antivirals sofosbuvir, simeprevir, daclatasvir, ledipasvir and 3D therapy containing ombitasvir/paritaprevir/ritonavir and dasabuvir followed. This review focuses on treatment outcomes and costs of introduced direct acting antivirals. We provide an overview on SVR-rates in clinical trials and clinical practice, treatment costs in different countries as well as results of cost-effectiveness analyses for different treatment strategies.

Ethical assessment of hepatitis C virus treatment: The lesson from first generation protease inhibitors

Since chronic hepatitis C has mostly become curable, issues concerning choice and allocation of treatment are of major concern. We assessed the foremost ethical issues in hepatitis C virus therapy with 1st generation protease inhibitors using the personalist ethical framework within the health technology assessment methodology. Our aim was to identify values at stake/in conflict and to support both the physicians' choices in hepatitis C therapy and social (macro-) allocation decision-making. The ethical assessment indicates that: (1) safety/effectiveness profile of treatment is guaranteed if its use is restricted to the patients subgroups who may benefit from it; (2) patients should be carefully informed, particularly on treatment deferral, and widespread information on these therapies should be implemented; (3) since treatment was proven to be cost-effective, its use is acceptable respecting resource macro-allocation. Concerning individual (micro-) location criteria: (a) criteria for eligibility to treatment should be clearly identified and updated periodically; (b) information on criteria for eligibility/deferral to treatment for specific patients' subgroups should be made widely known. Interferon-based regimens will disappear from use within the next year, with the introduction of highly effective/tolerable combination regimens of direct-acting antivirals, thus profoundly changing social choices. Nonetheless, our model could support future ethical assessment since the evaluation pertaining ethical domains remains generally applicable.

Novel α-2-macroglobulin cleaved fragments as biomarkers of early liver fibrosis in patients with chronic hepatitis C

ABSTRACT 

Aim: Liver biopsy is considered the gold standard for the diagnosis and staging of hepatic fibrosis in patients with chronic hepatitis C and is now progressively replaced by noninvasive procedures. We aimed at improving α-2-macroglobulin diagnostic value for liver fibrosis by identifying new isoforms that may be specifically related to early stages of the pathology. Materials & methods: α-2-Macroglobulin isoforms were characterized in serum samples from patients with chronic hepatitis C and mild (F1) to moderate (F2) fibrosis by proteomic methods. Results: New biological 40 kDa C-terminal α-2-macroglobulin fragments were identified as potential biomarkers of early fibrosis (fold change = 1.55; p < 0.01). Conclusion: The serum concentration of α-2-macroglobulin fragments allows a better differentiation of F1 and F2 fibrosis stages than total α-2-macroglobulin isoforms.