Directly observed pegylated interferon plus self-administered ribavirin for the treatment of hepatitis C virus infection in people actively using drugs: a randomized controlled trial

Hepatitis C Knowledge and Self-Reported Testing Behavior in the General Population in China: Online Cross-Sectional Survey

BACKGROUND

The World Health Organization has proposed a worldwide target of eliminating hepatitis C virus (HCV) by 2030. A better understanding of HCV, testing behaviors, and associated factors in the general population is essential.

OBJECTIVE

This study aimed to assess HCV knowledge, self-reported HCV testing behavior, and willingness to undergo HCV screening in the general Chinese population.

METHODS

A cross-sectional online survey of the general Chinese population aged ≥15 years was conducted from November 2021 to May 2023. Participant characteristics were assessed based on their knowledge level and uptake of HCV testing. Participants ever having heard of HCV were recognized as being aware of HCV and asked additional HCV knowledge questions using a brief, validated 9-item scale. Participants with 0-3 points and who were unaware of HCV were categorized as having poor knowledge, and those with 4-6 points and 7 points were categorized as having fair and good knowledge, respectively. Participant uptake of HCV testing, testing results, reasons for undergoing or not undergoing HCV testing, and willingness to undergo HCV screening were collected through self-reports. Ordinal and binary logistic regression analyses were used to assess factors associated with the HCV knowledge level and the uptake of HCV testing, respectively.

RESULTS

A total of 1491 valid participants' questionnaires were included. Of these, 714 (47.6%) participants were aware of HCV. The proportion of participants with poor, fair, and good HCV knowledge was 63.4% (945/1491), 9.3% (139/1491), and 27.3% (407/1491), respectively. A total of 465 (31.2%) participants reported ever undergoing HCV testing, and 4 (0.9%) were anti-HCV antibody positive. Most participants were tested for HCV following blood donation (353/465, 75.9%). The most common reasons for not undergoing HCV screening were a lack of HCV awareness (665/1026, 64.8%), followed by a low self-perceived risk of infection (176/1026, 17.2%). Of 1026 participants who had never undergone HCV testing, 937 (91.3%) were willing to undergo HCV screening if universal screening was provided at no cost. The HCV knowledge level was positively associated with the HCV testing rate. Participants who were less educated, lived in rural areas, resided in West China, and were currently alcohol drinkers had lower HCV knowledge and reduced odds of having undergone HCV testing. In contrast, participants with a blood donation history and a family history of hepatitis B virus or HCV infection had higher HCV knowledge and increased odds of prior testing. Participants aged ≥60 years had lower knowledge, and women had reduced odds of having undergone previous HCV testing.

CONCLUSIONS

The general population of China has low HCV knowledge and testing rate. There is an urgent need for enhanced HCV awareness and scaled-up HCV screening and treatment. Individuals who are less well educated, reside in less-developed areas, currently drink alcohol, and are female should be prioritized for health education and interventions.

Characterizing risk behaviour and reinfection rates for successful programs to engage core transmitters in HCV elimination (C-RESPECT)

BACKGROUND

Development of robust treatment programs among core transmitters (CT) of hepatitis C virus (HCV) are needed, including strategies to address reinfection risk. The aim of this study was to describe the effectiveness of direct-acting antiviral (DAA) treatment in CT versus non-CT populations and assess reinfection rates after successful treatment.

METHODS

Characterizing Risk Behaviour and Reinfection Rates for Successful Programs to Engage Core Transmitters in HCV Elimination (C-RESPECT) was a prospective, observational study of HCV-infected Canadian adult patients (genotypes 1, 3, and 4) treated with DAAs between 2017 and 2020.

RESULTS

The full analysis set included 429 participants (259 CT, 170 non-CT). Key differences were observed in baseline profiles: CT participants were younger (mean 42.3 [SD 11.2] y versus 55.0 [SD 11.1] y, respectively) and reported higher rates of social assistance (35.7% versus 14.8%), smoking (83.7% versus 52.4%), low socioeconomic status (yearly income <$15,000: 69.6% versus 43.9%), illicit drug use (83.7% versus 34.3%), and previous incarcerations (62.7% versus 36.9%). DAA treatment adherence was similar; 93 .5% versus 98.3% of CT versus non-CT participants completed the assigned treatment duration. Cure rates (sustained virologic response) were comparable, ranging from 94.9% to 98.1%. All reinfections were among CT participants, with a rate of 13.8/100 person-years (95% CI 9.2-20.8) with mean time to reinfection of 24.6 (SD 0.6) months.

CONCLUSIONS

CT and non-CT participants respond equally well to DAA treatment; however, with some reinfections among CT participants. Innovative multidisciplinary programs must be developed to mitigate this risk in this key population.

Hepatitis C reinfection after successful antiviral treatment among people who inject drugs: A meta-analysis

BACKGROUND & AIMS

HCV reinfection following successful treatment can compromise treatment outcomes. This systematic review assessed the rate of HCV reinfection following treatment among people with recent drug use and those receiving opioid agonist therapy (OAT).

METHODS

We searched bibliographic databases and conference abstracts for studies assessing post-treatment HCV reinfection rates among people with recent drug use (injecting or non-injecting) or those receiving OAT. Meta-analysis was used to cumulate reinfection rates and meta-regression was used to explore heterogeneity across studies.

RESULTS

Thirty-six studies were included (6,311 person-years of follow-up). The overall rate of HCV reinfection was 5.9/100 person-years (95% CI 4.1-8.5) among people with recent drug use (injecting or non-injecting), 6.2/100 person-years (95% CI 4.3-9.0) among people recently injecting drugs, and 3.8/100 person-years (95% CI 2.5-5.8) among those receiving OAT. Reinfection rates were comparable following interferon-based (5.4/100 person-years; 95% CI 3.1-9.5) and direct-acting antiviral (3.9/100 person-years; 95% CI 2.5-5.9) therapy. In stratified analysis, reinfection rates were 1.4/100 person-years (95% CI 0.8-2.6) among people receiving OAT with no recent drug use, 5.9/100 person-years (95% CI 4.0-8.6) among people receiving OAT with recent drug use, and 6.6/100 person-years (95% CI 3.4-12.7) among people with recent drug use not receiving OAT. In meta-regression analysis, longer follow-up was associated with lower reinfection rate (adjusted rate ratio [aRR] per year increase in mean/median follow-up 0.77; 95% CI 0.69-0.86). Compared with people receiving OAT with no recent drug use, those with recent drug use receiving OAT (aRR 3.50; 95% CI 1.62-7.53), and those with recent drug use not receiving OAT (aRR 3.96; 95% CI 1.82-8.59) had higher reinfection rates.

CONCLUSION

HCV reinfection risk following treatment was higher among people with recent drug use and lower among those receiving OAT. The lower rates of reinfection observed in studies with longer follow-up suggested higher reinfection risk early post-treatment.

LAY SUMMARY

Our findings demonstrate that although reinfection by hepatitis C virus occurs following successful treatment in people with recent drug use, the rate of hepatitis C reinfection is lower than the rates of primary infection reported in the literature for this population - reinfection should not be used as a reason to withhold therapy from people with ongoing injecting drug use. The rate of hepatitis C reinfection was lowest among people receiving opioid agonist therapy with no recent drug use. These data illustrate that harm reduction services are required to reduce the reinfection risk, while regular post-treatment hepatitis C assessment is required for early detection and retreatment.

Critical View on the Usage of Ribavirin in Already Existing Psychostimulant-Use Disorder

Substance-use disorder represents a frequently hidden non-communicable chronic disease. Patients with intravenous drug addiction are at high risk of direct exposure to a variety of viral infections and are considered to be the largest subpopulation infected with the hepatitis C virus. Ribavirin is a synthetic nucleoside analog that has been used as an integral component of hepatitis C therapy. However, ribavirin medication is quite often associated with pronounced psychiatric adverse effects. It is not well understood to what extent ribavirin per se contributes to changes in drug-related neurobehavioral disturbances, especially in the case of psychostimulant drugs, such as amphetamine. It is now well-known that repeated amphetamine usage produces psychosis in humans and behavioral sensitization in animals. On the other hand, ribavirin has an affinity for adenosine A1 receptors that antagonistically modulate the activity of dopamine D1 receptors, which play a critical role in the development of behavioral sensitization. This review will focus on the current knowledge of neurochemical/ neurobiological changes that exist in the psychostimulant drug-addicted brain itself and the antipsychotic-like efficiency of adenosine agonists. Particular attention will be paid to the potential side effects of ribavirin therapy, and the opportunities and challenges related to its application in already existing psychostimulant-use disorder.

Reinfection in a large cohort of prison inmates with sustained virological response after treatment of chronic hepatitis C in Catalonia (Spain), 2002-2016

BACKGROUND

Prisoners and other high-risk patients who show a sustained virological response (SVR) after treatment for hepatitis C virus (HCV) can become reinfected. We aimed to calculate the rate of HCV reinfection in a large cohort of inmates with SVR and to determine factors that predict reinfection.

METHODS

We included all inmates treated for hepatitis C in Catalonia (Spain) from January 2002 to December 2016 who achieved SVR and in whom viral load was subsequently determined. The incidence rate was calculated per 100 person-years (100 py) of follow up. Risk factors associated with reinfection were evaluated by bivariate log-rank test and multivariate Cox regression. Hazard ratio (HR) and their 95% confidence intervals (CI) were calculated.

RESULTS

602 patients were included, with a mean age of 37.9 years: 95% were men, 74.1% had a history of intravenous drug use (IDU) and 28.7% were HIV-infected. Patients were followed for a total of 2154.9 years (average 3.58 ± 3.1 years). 63 (10.5%) had HCV reinfection. 41 (65.1%) presented different genotype/subgenotype, 8 the initial genotype/subgenotype, and in 14 (22.2%) the genotype could not be determined. Of the 21 reinfected patients who were interviewed, 20 (95.2%) reported IDU after antiviral treatment, and 7 (33.3%) during treatment. The overall incidence of reinfection was 2.9 cases per 100 py. All reinfections occurred in patients with IDU history. At multivariate level, HIV infection was associated with reinfection (HR = 3.03; CI:1.82-5.04).

CONCLUSION

In HIV-infected inmates with IDU history, the rate of reinfection of HCV post-SVR is very high. Prisons play a key role in the detection and treatment of infection and reinfection by HCV and in the post-treatment monitoring in these patients, which should be combined with counseling and the optimization of the harm reduction programs. Effective control of these vulnerable groups favours the elimination of the HCV infection.

High response and re-infection rates among people who inject drugs treated for hepatitis C in a community needle and syringe programme

To achieve WHO hepatitis C virus (HCV) elimination targets by 2030, mathematical models suggest there needs to be significant scale-up of treatment among people who inject drugs (PWID). We tested whether people who actively inject drugs can be recruited and treated successfully through a community needle and syringe programme (NSP), and assessed rates of re-infection. 105 HCV RNA positive participants were enrolled prospectively. Participants were recruited from the largest NSP in Dundee over 42 months. 94/105 individuals commenced treatment. Genotype 1 (G1) individuals (n = 37) were treated with peg-interferon+ribavirin+Simepravir/Telaprevir. Genotype 2/3 (G2/3) (n = 57) received peg-interferon+ribavirin. Weekly study visits took place within the NSP. Mean age of participants was 34.0 years (SD 6.9), 71.3% (61/94) were male. One in five (20/94) participants were homeless. 68.1% (64/94) were on OST (opiate substitution therapy) at enrolment; participants injected median 6.5 times/wk. In terms of clinical outcomes, >80% treatment adherence was 71.3% (67/94). There was no difference in SVR-12 rates by genotype: 81.0% (30/37) for G1 and 82.5% (47/55) for G2/3. At 18 months post-treatment, 15/77 participants were reinfected, followed up over 69.8 person-years, yielding a re-infection rate of 21.5/100 person-years (95% CI 13.00-35.65). This trial demonstrates that HCV treatment can be delivered successfully to the target population of treatment as prevention strategies. We report higher rates of re-infection than existing estimates among PWID. Scale-up of HCV treatment should be pursued alongside a comprehensive programme of harm reduction interventions to help minimize re-infection and reduce HCV transmission.

Strategies to Reduce Hepatitis C Virus Reinfection in People Who Inject Drugs

Reinfection after direct-acting antiviral therapy may pose a challenge to hepatitis C virus elimination efforts. Reinfection risk is cited as a reason for not offering treatment to people who inject drugs. As treatment scale-up expands among populations with risks for reacquisition, acknowledgment that reinfection can and will occur is essential. Efforts to prevent and manage reinfection should be incorporated into individual- and population-level strategies. The risk of reinfection after successful treatment emphasises the need for education, harm reduction, and posttreatment surveillance. Reinfection must not be considered an impediment to treatment, if hepatitis C virus elimination is to be achieved.

Treatment of Chronic Hepatitis C in Patients Receiving Opioid Agonist Therapy: A Review of Best Practice

Injection drug use is the most common transmission route for hepatitis C. High rates of infection are observed among individuals on opioid agonist therapy. Although people who inject drugs carry the highest burden, few have initiated treatment. We present a comprehensive review of the evidence on the efficacy of HCV medications, drug-drug interactions, and barriers to and models of care. Studies have demonstrated comparable efficacy for individuals who are on opioid agonist therapy compared with those who are not. We propose that a strategy of treatment and cure-as-prevention is imperative in this population to curb the hepatitis C epidemic.

Clinical Characteristics and Treatment Efficasy of Chronic HCV Infection Among Intravenous Drug Users in Tuzla Canton

Introduction:

Chronic HCV infection is chronic inflamatory liver disease caused by hepatitis C virus. Anti HCV prevalence among intravenous drug users (IVDU) is very high and it accounts 40% -90% (60%-90%) with the risk of 80% of developing the chronic infection.

Aim:

The aims of this study were: a) to compare clinical characteristics of chronic HCV infection among IVDU and non-users population and to detect their impact to treatment outcome; b) to investigate the treatment efficacy comparing sustained viral response (SVR) in these two populations in Tuzla Canton.

Patients and methods:

The study was retrospective-prospective and included 45 IVDU of both sexes from Tuzla Canton which were treated from chronic HCV infection with Pegilated interferon 2a/2b + ribavirin in the Clinic for Infectious Diseases and Clinic for Internal Disease of University Clinical Centre in Tuzla. The control group were presented by non-users who completed therapy in both Clinics. For statistical analyses it was used statistical package SPSS 20,0 (SPSS Inc, Chicago, IL, USA) with tests of descriptive statistics with measures of central tendency and dispersion. Quantitative variables were tested by t-test or by Mann-Whitney test. Qualitative variables were tested by hi-square test or by Fisher’s test. The standard analyse of level’s risk was used too. The analyse of predictive value of EVR for achieving the ETR and SVR was done by cross-tabulation. The impact of known factors for achieving the SVR was evaluated by logistic regression analyses. All tests were done with statistical level of significance of 95% (p=0,05).

Results:

Men were more dominant in the test group (93,3% / 61,7%), also younger age (p<0,001) and lower BMI (p=0,019). The test group had significant higher basal values of Le, Hb, Plt and ALT and tendency to lower stages of fibrosis (p=0,08). The difference in genotype frequencies was statistically significant (p=0,001) with clearly dominance of G3 and G4 among IVDU. Treatment was not complited by two patients in both groups (4,4% /3,3%). EVR was significantly higher in test group (p=0,001) so did the ETR (p=0,002) and SVR (p<0,001). Predictive factors for SVR were: age (negative predictive factor), male sex, absence of reduction of pegilated interferon and ribavirin, Metavir stage of fibrosis and presence of EVR.

Conclusion:

Population of IVDU were adherent to treatment protocol and with excellent treatment response they justified the hope of health care workers for success treatment of this population.

HCV Cure and Reinfection Among People With HIV/HCV Coinfection and People Who Inject Drugs

PURPOSE OF REVIEW

Highly effective, well-tolerated interferon-free direct-acting antivirals (DAA) have revolutionised hepatitis C virus (HCV) therapeutics, with the opportunity for broad treatment scale-up among marginalised or "high-risk" populations, including people who inject drugs (PWID) and people with HIV/HCV coinfection.

RECENT FINDINGS

Concern that HCV reinfection may compromise HCV treatment outcomes is sometimes cited as a reason for not offering treatment to current and former PWID. However, the incidence of reinfection following interferon-based treatment for chronic HCV is low among PWID. Reinfection rates in HIV-positive men-who-have-sex-with-men (MSM) are varied, with high incidence reported in some cohorts. Mathematical modelling suggests that substantial reductions in HCV incidence and prevalence could be achieved with targeted DAA therapy among those at the highest risk of ongoing transmission. This review will summarise the recent literature on DAA efficacy in PWID and people with HIV/HCV coinfection, discuss the individual- and population-level impact of DAA treatment scale-up and reinfection, and highlight ongoing and future research questions in expanding HCV care and treatment to those populations at high risk of ongoing HCV transmission.

Initiating HCV treatment with direct acting agents in opioid agonist treatment: When to start for people co-infected with HIV?

BACKGROUND

Direct acting antivirals (DAA) raise the possibility of eliminating Hepatitis C virus (HCV) among people who inject drugs (PWID). However, concerns regarding treatment retention and reinfection challenge implementation efforts. Opioid agonist treatment (OAT) provides an opportunity to engage HCV-positive PWID into DAA-based treatment. Our objective was to identify when OAT adherence sufficiently improved to inform DAA initiation in OAT settings, assuming continuous OAT retention for at least twelve weeks is necessary to complete the DAA treatment course.

METHODS

This was a retrospective cohort study of HCV/HIV co-infected PWID from a population-level linked administrative database of people diagnosed and living with HIV in British Columbia, Canada between 01/1996 and 12/2013. We used monthly follow-up data after initial OAT entry and considered the effects of demographics, disease severity, and HIV and OAT treatment characteristics over time on the probability of subsequent OAT retention of ≥12 weeks, and ≥8 weeks for sensitivity analysis. We fit a generalized linear mixed model to the overall study population, and on stratified samples of those continuously engaged on combination antiretroviral therapy (≥95% ART adherence). A set of monthly indicator variables (months 1, …, 7, >7) were included to fulfil the study objective.

RESULTS

Our study included 1427 HCV/HIV co-infected PWID (39.0% female, 68.8% OAT-naïve). The odds of subsequent twelve-week retention in OAT were statistically significantly greater in month 3 versus month 1 (adjusted odds ratio: 1.18; 95% confidence interval: 1.02, 1.37); and the odds of subsequent 8-week retention in OAT were statistically significantly greater in month 2 versus month 1 (1.15, 95% CI: 1.02, 1.31). Among continuously ART-adherent individuals, the odds of subsequent twelve-week retention were not statistically significantly greater than in month 1 (month 2: 1.12 (0.82, 1.51); month 3: 1.08 (0.79, 1.47); month 4: 1.24 (0.91, 1.71)).

CONCLUSION

We provide evidence that among HCV/HIV co-infected PWID, those retained in OAT for three or more months had higher odds of completing an additional twelve weeks of OAT, compared to no difference in those already receiving ART. These data may have implications for adherence to DAA therapy and further studies are needed to understand the optimal timing of DAA therapy in PWID receiving and not receiving OAT.

HCV epidemiology in high-risk groups and the risk of reinfection

Injecting risk behaviours among people who inject drugs (PWID) and high-risk sexual practices among men who have sex with men (MSM) are important routes of hepatitis C virus (HCV) transmission. Current direct-acting antiviral treatment offers unique opportunities for reductions in HCV-related liver disease burden and epidemic control in high-risk groups, but these prospects could be counteracted by HCV reinfection due to on-going risk behaviours after successful treatment. Based on existing data from small and heterogeneous studies of interferon-based treatment, the incidence of reinfection after sustained virological response range from 2-6/100 person years among PWID to 10-15/100 person years among human immunodeficiency virus-infected MSM. These differences mainly reflect heterogeneity in study populations with regards to risk behaviours, but also reflect variations in study designs and applied virological methods. Increasing levels of reinfection are to be expected as we enter the interferon-free treatment era. Individual- and population-level efforts to address and prevent reinfection should therefore be undertaken when providing HCV care for people with on-going risk behaviour. Constructive strategies include acknowledgement, education and counselling, harm reduction optimization, scaled-up treatment including treatment of injecting networks, post-treatment screening, and rapid retreatment of reinfections.

CIHR Canadian HIV Trials Network Coinfection and Concurrent Diseases Core Research Group: 2016 Updated Canadian HIV/Hepatitis C Adult Guidelines for Management and Treatment

Background. Hepatitis C virus (HCV) coinfection occurs in 20-30% of Canadians living with HIV and is responsible for a heavy burden of morbidity and mortality. Purpose. To update national standards for management of HCV-HIV coinfected adults in the Canadian context with evolving evidence for and accessibility of effective and tolerable DAA therapies. The document addresses patient workup and treatment preparation, antiviral recommendations overall and in specific populations, and drug-drug interactions. Methods. A standing working group with HIV-HCV expertise was convened by The Canadian Institute of Health Research HIV Trials Network to review recently published HCV antiviral data and update Canadian HIV-HCV Coinfection Guidelines. Results. The gap in sustained virologic response between HCV monoinfection and HIV-HCV coinfection has been eliminated with newer HCV antiviral regimens. All coinfected individuals should be assessed for interferon-free, Direct Acting Antiviral HCV therapy. Regimens vary in content, duration, and success based largely on genotype. Reimbursement restrictions forcing the use of pegylated interferon is not acceptable if optimal patient care is to be provided. Discussion. Recommendations may not supersede individual clinical judgement. Treatment advances published since December 2015 are not considered in this document.

Novel interventions to prevent HIV and HCV among persons who inject drugs

Persons who inject drugs (PWID) are at high risk for infection with and poor outcomes from HIV and hepatitis C virus (HCV). Well-established interventions for HIV/HCV prevention among PWID include syringe access, opioid agonist maintenance treatment, and supervised injection facilities, yet these interventions remain unavailable or inadequately resourced in much of the world. We review recent literature on biomedical and behavioral interventions to reduce the burden of HIV/HCV among PWID, with an emphasis on randomized controlled trials and quasi-experimental studies. Since 2013, there have been significant advancements in utilizing antiviral therapy and behavioral interventions for prevention among PWID, including approaches that address the unique needs of couples and sex workers. In addition, there have been significant developments in pharmacotherapies for substance use and the implementation of naloxone for opioid overdose prevention. Notwithstanding multiple ongoing structural challenges in delivering HIV/HCV prevention interventions to PWID, these emerging and rigorously evaluated interventions expand possibilities for prevention among PWID.

Supervised conventional interferon α2a in combination with ribavirin therapy is the preferred alternative for treatment of chronic hepatitis C

Objective:

To document the significant sustained virological response with supervised conventional interferon α and ribavirin therapy in hepatitis C virus (HCV)-infected patients, this study was planned.

Materials and Methods:

Sixty chronic hepatitis C naive patients were included in this study. Complete blood counts, prothrombin time, ALT, AST, and qualitative HCV RNA were done. Conventional interferon (INF) α2a, 3MIU, S.C and ribavirin 1000 mg PO was given as supervised therapy for 24 weeks in genotype 3 and 48 weeks in genotype 1 and 4 HCV patients. Qualitative HCV RNA was repeated at 12 weeks, 24 weeks for HCV infections with genotype 1, 2, 3 and 4, at 48 weeks for genotype 1 and 4, and thereafter 6 months after completion of treatment. End virological and sustained virological responses were observed.

Results:

Out of 60 patients, 55 completed the study. Five patients were lost to follow-up. Overall SVR was seen in 47 patients (85.4%) and 4 patients had relapses.

Conclusion:

Significant sustained virological response rates were seen in patients with supervised conventional INF α2a and ribavirin therapy.

Mixed HCV infection and reinfection in people who inject drugs--impact on therapy

The majority of new and existing cases of HCV infection in high-income countries occur among people who inject drugs (PWID). Ongoing high-risk behaviours can lead to HCV re-exposure, resulting in mixed HCV infection and reinfection. Assays used to screen for mixed infection vary widely in sensitivity, particularly with respect to their capacity for detecting minor variants (<20% of the viral population). The prevalence of mixed infection among PWID ranges from 14% to 39% when sensitive assays are used. Mixed infection compromises HCV treatment outcomes with interferon-based regimens. HCV reinfection can also occur after successful interferon-based treatment among PWID, but the rate of reinfection is low (0-5 cases per 100 person-years). A revolution in HCV therapeutic development has occurred in the past few years, with the advent of interferon-free, but still genotype-specific regiments based on direct acting antiviral agents. However, little is known about whether mixed infection and reinfection has an effect on HCV treatment outcomes in the setting of new direct-acting antiviral agents. This Review characterizes the epidemiology and natural history of mixed infection and reinfection among PWID, methodologies for detection, the potential implications for HCV treatment and considerations for the design of future studies.

Portraying persons who inject drugs recently infected with hepatitis C accessing antiviral treatment: a cluster analysis

Objectives. To empirically determine a categorization of people who inject drug (PWIDs) recently infected with hepatitis C virus (HCV), in order to identify profiles most likely associated with early HCV treatment uptake. Methods. The study population was composed of HIV-negative PWIDs with a documented recent HCV infection. Eligibility criteria included being 18 years old or over, and having injected drugs in the previous 6 months preceding the estimated date of HCV exposure. Participant classification was carried out using a TwoStep cluster analysis. Results. From September 2007 to December 2011, 76 participants were included in the study. 60 participants were eligible for HCV treatment. Twenty-one participants initiated HCV treatment. The cluster analysis yielded 4 classes: class 1: Lukewarm health seekers dismissing HCV treatment offer; class 2: multisubstance users willing to shake off the hell; class 3: PWIDs unlinked to health service use; class 4: health seeker PWIDs willing to reverse the fate. Conclusion. Profiles generated by our analysis suggest that prior health care utilization, a key element for treatment uptake, differs between older and younger PWIDs. Such profiles could inform the development of targeted strategies to improve health outcomes and reduce HCV infection among PWIDs.

Eligibility of persons who inject drugs for treatment of hepatitis C virus infection

In this decade, an increase is expected in end-stage liver disease and hepatocellular carcinoma, most commonly caused by hepatitis C virus (HCV) infection. Although people who inject drugs (PWID) are the major source for HCV infection, they were excluded from antiviral treatments until recently. Nowadays there is incontrovertible evidence in favor of treating these patients, and substitution therapy and active substance use are no longer contraindications for antiviral treatment. The viral clearance in PWID after HCV antiviral treatment with interferon or pegylated interferon combined with ribavirin is comparable to the viral clearance in non-substance users. Furthermore, multidisciplinary approaches to delivering treatment to PWID are advised, and their treatment should be considered on an individualized basis. To prevent the spread of HCV in the PWID community, recent active PWID are eligible for treatment in combination with needle exchange programs and substitution therapy. As the rate of HCV reinfection is low after HCV antiviral treatment, there is no need to withhold HCV treatment due to concerns about reinfection alone. Despite the advances in treatment efficacies and data supporting their success, HCV assessment of PWID and initiation of antiviral treatment remains low. However, the proportion of PWID assessed and treated for HCV is increasing, which can be further enhanced by understanding the barriers to and facilitators of HCV care. Removing stigmatization and implementing peer support and group treatment strategies, in conjunction with greater involvement by nurse educators/practitioners, will promote greater treatment seeking and adherence by PWID. Moreover, screening can be facilitated by noninvasive methods for detecting HCV antibodies and assessing liver fibrosis stages. Recently, HCV clearance has become a major endpoint in the war against drugs for the Global Commission on Drug Policy. This review highlights the most recent evidence concerning HCV infection and treatment strategies in PWID.

The hepatitis C cascade of care: identifying priorities to improve clinical outcomes

BACKGROUND

As highly effective hepatitis C virus (HCV) therapies emerge, data are needed to inform the development of interventions to improve HCV treatment rates. We used simulation modeling to estimate the impact of loss to follow-up on HCV treatment outcomes and to identify intervention strategies likely to provide good value for the resources invested in them.

METHODS

We used a Monte Carlo state-transition model to simulate a hypothetical cohort of chronically HCV-infected individuals recently screened positive for serum HCV antibody. We simulated four hypothetical intervention strategies (linkage to care; treatment initiation; integrated case management; peer navigator) to improve HCV treatment rates, varying efficacies and costs, and identified strategies that would most likely result in the best value for the resources required for implementation.

MAIN MEASURES

Sustained virologic responses (SVRs), life expectancy, quality-adjusted life expectancy (QALE), costs from health system and program implementation perspectives, and incremental cost-effectiveness ratios (ICERs).

RESULTS

We estimate that imperfect follow-up reduces the real-world effectiveness of HCV therapies by approximately 75%. In the base case, a modestly effective hypothetical peer navigator program maximized the number of SVRs and QALE, with an ICER compared to the next best intervention of $48,700/quality-adjusted life year. Hypothetical interventions that simultaneously addressed multiple points along the cascade provided better outcomes and more value for money than less costly interventions targeting single steps. The 5-year program cost of the hypothetical peer navigator intervention was $14.5 million per 10,000 newly diagnosed individuals.

CONCLUSIONS

We estimate that imperfect follow-up during the HCV cascade of care greatly reduces the real-world effectiveness of HCV therapy. Our mathematical model shows that modestly effective interventions to improve follow-up would likely be cost-effective. Priority should be given to developing and evaluating interventions addressing multiple points along the cascade rather than options focusing solely on single points.

Can hepatitis C virus infection be eradicated in people who inject drugs?

People who inject drugs (PWID) represent the core of the hepatitis C virus (HCV) epidemic in many countries and HCV-related disease burden continues to rise. There are compelling data demonstrating that with the appropriate programs, treatment for HCV infection among PWID is successful, with responses to therapy similar those observed in large randomized controlled trials in non-PWID. However, assessment and treatment for HCV infection lags far behind the numbers who could benefit from therapy, related to systems-, provider- and patient-related barriers to care. The approaching era of interferon-free directly acting antiviral therapy has the potential to provide one of the great advances in clinical medicine. Simple, tolerable and highly effective therapy will likely address many of these barriers, thereby enhancing the numbers of PWID cured of HCV infection. This commentary will consider why we should strive for the eradication of HCV infection among PWID, whether eradication of HCV infection among PWID is feasible, components that would be needed to achieve eradication of HCV infection in PWID, potential settings and strategies required to establish programs targeted towards eradicating HCV infection among PWID and the feasibility of eradication versus elimination of HCV infection among PWID. This article forms part of a symposium in Antiviral Research on "Hepatitis C: next steps toward global eradication."