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

Needle and syringe sharing among people who have recently injected drugs in Australia: The ETHOS Engage Study

INTRODUCTION

Understanding needle/syringe sharing is crucial for reducing hepatitis C virus (HCV) infection and reinfection. This study aimed to assess the prevalence and factors associated with needle/syringe sharing among people who inject drugs in Australia, including those previously receiving HCV treatment.

METHODS

The ETHOS Engage study was an observational cohort study which collected self-reported survey data on demographic and drug use information from people who inject drugs attending drug treatment clinics and needle and syringe programs over two waves between May 2018 and June 2021. Logistic regression was used to identify factors associated with needle/syringe sharing.

RESULTS

Overall, 1555/2395 people enrolled in ETHOS Engage (65%) injected drugs in the past month. Among these, 432 (28%) reported needle/syringe sharing in the past month and 276 (18%) reported receptive sharing. Factors associated with receptive sharing included younger age (adjusted odds ratio [aOR] 1.72; 95% confidence interval [CI] 1.28-2.30), recent incarceration (aOR 2.04; 95% CI 1.40-2.94), more frequent injecting (≥daily vs. less than weekly; aOR 2.59; 95% CI 1.75-3.84) and unstable housing (aOR 1.78; 95% CI 1.26-2.52). Among 560 participants with prior HCV treatment, 87 (16%) reported receptive sharing with younger age (aOR 2.42; 95% CI 1.45-4.05) and daily or greater injection frequency (aOR 2.51; 95% CI 1.31-4.83) associated with receptive sharing.

DISCUSSION AND CONCLUSIONS

Needle/syringe sharing was common among this population accessing harm reduction services. This study identifies high-risk populations with needle/syringe sharing. Research is needed to optimise HCV treatment to ensure people with ongoing risk behaviours receive adequate harm reduction following treatment to prevent reinfection.

The experiences of people who use injection drugs with accessing hepatitis c testing and diagnosis in western countries: A scoping review

BACKGROUND

The purpose of this scoping review was to summarize the literature that reported on the experiences of people who use injection drugs' access to hepatitis C testing and diagnosis in Western countries.

METHODS

The initial search was conducted in 2020 and an updated review was completed in 2022. Seven electronic databases were searched using a peer-reviewed search strategy and included: full-text, peer-reviewed studies with people who inject(ed) drugs, hepatitis C testing or diagnosis, conducted in Western countries. Excluded were studies published prior to 2014 and intervention studies. Two-step screening was conducted in duplicate. Conventional content analysis was used.

RESULTS

Six studies were found from the search. The studies were published between 2014 and 2021 in Australia, United Kingdom, and United States. A total of 19 participant characteristics were extracted to contextualize their experiences, demonstrating a lack of demographic data. Four themes were found: Awareness and Knowledge, Stigma, Healthcare Service, and Psychological Responses. There were 58 occurrences of client quotes where participants described their experiences, 29 occurrences of quotes describing client-identified barriers, and 14 occurrences of quotes describing client-identified facilitators.

CONCLUSION

A scoping review was conducted to present the experiences, barriers, and facilitators of people who use injection drugs to hepatitis C testing. The lack of demographic data and connection to client quotes further exacerbates the inequities among the population by overlooking their intragroup identities. Understanding their experiences of accessing hepatitis C testing and collecting demographic data will help advance health policies and interventions targeting people who use injection drugs.

The rate of hepatitis C reinfection in Canadians coinfected with HIV and its implications for national elimination

BACKGROUND

The World Health Organisation (WHO) has set targets for the rate of new infections as a way to measure progress towards the elimination of hepatitis C virus (HCV) as a public health threat. As more people are successfully treated for HCV, a higher proportion of new infections will be reinfections. We consider whether the reinfection rate has changed since the interferon era and what we can infer about national elimination efforts from the current reinfection rate.

METHODS

The Canadian Coinfection Cohort is representative of HIV HCV coinfected people in clinical care. We selected cohort participants successfully treated for a primary HCV infection either in the interferon era or in the era of direct acting antivirals (DAAs). Selected participants were followed from 12 weeks after completing a successful treatment until the end of 2019 or until their last measured HCV RNA. We estimated the reinfection rate in each treatment era, overall and in participant subgroups, using proportional hazard models appropriate for interval censored data.

RESULTS

Among 814 successfully treated participants with additional HCV RNA measurements, there were 62 reinfections. The overall reinfection rate was 2.6 (95% confidence interval, CI, 1.2-4.1) /100 person years (PY) in the interferon era and 3.4 (95% CI 2.5-4.4) /100 PY in the DAA era. The rate in those reporting injection drug use (IDU) was much higher: 4.7 (95% CI 1.4-7.9) /100 PY and 7.6 (95% CI 5.3-10) /100 PY in the interferon and DAA eras respectively.

CONCLUSION

The overall reinfection rate in our cohort is now above the WHO target set for new infections in people who inject drugs. The reinfection rate in those reporting IDU has increased since the interferon era. This suggests Canada is not on track to achieve HCV elimination by 2030.

National trends in retreatment of HCV due to reinfection or treatment failure in Australia

BACKGROUND & AIMS

Population-level uptake of direct-acting antiviral (DAA) treatment for hepatitis C virus (HCV) infection, including retreatment, can be estimated through administrative pharmaceutical dispensation data. However, the reasons for retreatment are not captured in these data. We developed a machine learning model to classify retreatments as reinfection or treatment failure at a national level.

METHODS

Retreatment data from the REACH-C cohort (n = 10,843 treated with DAAs; n = 320 retreatments with known reason), were used to train a random forest model. Nested cross validation was undertaken to assess model performance and to optimise hyperparameters. The model was applied to data on DAA retreatment dispensed during 2016-2021 in Australia, to identify the reason for retreatment (treatment failure or reinfection).

RESULTS

Average predictive accuracy, precision, sensitivity, specificity and F₁-score for the model were 96.3%, 96.5%, 96.3%, 96.3% and 96.3%, respectively. Nationally, 95,272 individuals initiated DAAs, with treatment uptake declining from 32,454 in 2016 to 6,566 in 2021. Of those treated, 6,980 (7%) were retreated. Our model classified 51.8% (95% CI 46.7-53.6%; n = 3,614) of cases as reinfection and 48.2% (95% CI 46.4-53.3%; n = 3,366) as treatment failure. Retreatment for reinfection increased steadily over the study period from 14 in 2016 to 1,092 in 2020, stabilising in 2021. Retreatment for treatment failure increased from 73 in 2016 to 1,077 in 2019, then declined to 515 in 2021. Among individuals retreated for treatment failure, 50% had discontinued initial treatment.

CONCLUSIONS

We used a novel methodology with high classification accuracy to evaluate DAA retreatment patterns at a national level. Increases in retreatment uptake for treatment failure corresponded to the availability of pangenotypic and salvage regimens. Increasing retreatment uptake for reinfection likely reflects increasing reinfection incidence.

IMPACT AND IMPLICATIONS

This study used machine learning methodologies to analyse national administrative data and characterise trends in HCV retreatment due to reinfection and treatment failure. Retreatment for reinfection increased over time, reflecting increasing numbers of people at risk for reinfection following HCV cure. Increased retreatment for treatment failure corresponded to the availability of pangenotypic and salvage DAA regimens. The findings of this study can be used by public health agencies and policy makers to guide and assess HCV elimination strategies, while the novel methodology for monitoring trends in HCV retreatment has the potential to be used in other settings, and health conditions.

Improving hepatitis C screening and access to treatment

ABSTRACT

The rising prevalence of opioid use disorder and injection drug use has resulted in an increasing incidence of chronic hepatitis C virus (HCV) infection. Although older adults historically have represented the bulk of HCV infections in the United States, demographics have shifted and most new infections are presenting in younger patients. As a result, screening guidelines for HCV have evolved, moving toward a near-universal screening paradigm. Rates of screening and linkage to care remain low, attributed to the fact that underserved populations are disproportionately affected and often have limited access to specialty care. Collaborative models to treat HCV using primary care providers have been proposed to facilitate linkage to care and reduce transmission.

Reinfection and Risk Behaviors After Treatment of Hepatitis C Virus Infection in Persons Receiving Opioid Agonist Therapy : A Cohort Study

BACKGROUND

Hepatitis C virus (HCV) reinfection after successful treatment may reduce the benefits of cure among people who inject drugs.

OBJECTIVE

To evaluate the rate of HCV reinfection for 3 years after successful treatment among people receiving opioid agonist therapy (OAT).

DESIGN

A 3-year, long-term, extension study of persons enrolled in the CO-STAR (Hepatitis C Patients on Opioid Substitution Therapy Antiviral Response) study (ClinicalTrials.gov: NCT02105688).

SETTING

55 clinical trial sites in 13 countries.

PATIENTS

Aged 18 years and older with chronic HCV infection with genotypes 1, 4, or 6 receiving stable OAT.

INTERVENTION

No treatments were administered.

MEASUREMENTS

Serum samples were assessed for HCV reinfection. Urine drug screening was performed.

RESULTS

Among 296 participants who received treatment, 286 were evaluable for reinfection and 199 were enrolled in the long-term extension study. The rate of HCV reinfection was 1.7 [95% CI, 0.8 to 3.0] per 100 person-years; 604 person-years of follow-up). A higher rate of reinfection was seen among people with recent injecting drug use (1.9 [95% CI, 0.5 to 4.8] per 100 person-years; 212 person-years). Ongoing drug use and injecting drug use were reported by 59% and 21% of participants, respectively, at the 6-month follow-up visit and remained stable during 3 years of follow-up.

LIMITATIONS

Participants were required to be 80% adherent to OAT at baseline and may represent a population with higher stability and lower risk for HCV reinfection. Rate of reinfection may be underestimated because all participants did not continue in the long-term extension study; whether participants who discontinued were at higher risk for reinfection is unknown.

CONCLUSION

Reinfection with HCV was low but was highest in the first 24 weeks after treatment completion and among people with ongoing injecting drug use and needle-syringe sharing.

PRIMARY FUNDING SOURCE

Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc.

Reinfection rate of hepatitis C in HIV-1 positive men who have sex with men: A systematic review and meta-analysis

Purpose

A reduction of 80% in new Hepatitis C virus (HCV) infection is expected by 2030. However, high HCV reinfection rates have been reported among the high-risk population. This meta-analysis aimed to assess the HCV reinfection rate after successful treatment of HIV-1 coinfected MSM populations.

Methods

Bibliographic databases were searched and a random-effect model was utilized to calculate the pooled HCV reinfection rate. Sub-group and meta-regression were used to explore heterogeneity among selected studies. A funnel plot and Egger's regression test were performed to estimate the publication bias.

Results

Sixteen studies with 9,017.2 person-years (PY) follow-up were included. The overall HCV reinfection rate following successful treatment among HIV-1-infected MSM was 5.27/100 PY (95% CI, 3.98, 6.96). Lower reinfection rates were observed in developed parts of Europe (5.28/100 PY; 95% CI, 3.73, 6.84) and North America (3.92/100 PY; 95% CI, 1.67, 6.17). Reinfection rates among people with HCV test intervals of fewer than 6 months (7.59/100 PY; 95% CI: 5.15, 10.03) were significantly higher than those with more than 6 months test interval (2.88/100 PY; 95% CI: 2.26, 3.50), with an adjusted RR of 1.86 (95% CI, 1.06, 3.13). The adjusted study factors explained 91.03% the of studies' heterogeneity.

Conclusion

HCV reinfection rate was high in successfully treated MSM who were coinfected with HIV-1. A shorter HCV test interval may help to explore more HCV reinfections. HCV reinfection rate studies from HIV-1 coinfected MSM in underdeveloped countries are urgently needed.

Meta registration

PROSPERO: CRD42021285206, URL: https://www.crd.york.ac.uk/prospero/.

Development and pilot-testing of a hepatitis C reinfection prevention intervention for patients in treatment for hepatitis C infection

•We developed a two-session behavioral intervention to prevent HCV reinfection.•The intervention was piloted at an OTP and integrated into HCV treatment.•Baseline data showed limited knowledge & application of safer injection practices.•Implementation barriers included logistics and the lack of financial incentive.•Adaptations addressed barriers, yielding a more feasible and acceptable intervention.

A Global Systematic Review of Hepatitis C Elimination Efforts through Micro-Elimination

Microelimination targets specific subpopulations and/or geographic settings for hepatitis C virus (HCV) elimination. This review reports on global HCV microelimination literature published from 2013 to 2020. Data were extracted from publications to report a score based on the four key components defining microelimination. Sustained virologic response (SVR) and treatment initiation proportions were calculated for each manuscript and grouped means of these estimates were compared depending on microelimination score and care setting. A total of 83% of the studies were from high-income settings and mainly included people who use drugs or those incarcerated. Among manuscripts, 18 had "low" microelimination scores, 11 had "high" scores, and the differences in mean proportion who initiated treatment and achieved SVR between low and high score groups were statistically significant. Microelimination can be a useful complementary strategy for driving engagement in HCV treatment and cure. Our analysis suggests that adhering to more of the core microelimination components can improve outcomes. This study is registered with Prospero, registration identification: CRD42020175211.

Primary Care Associated With Follow Up Viral Load Testing in Patients Cured of Hepatitis C Infection With Direct Acting Antivirals at a Multidisciplinary Addiction Treatment Program: Insights From a Real-World Setting

OBJECTIVES

Treatment of hepatitis C virus infection (HCV) with direct acting antiviral therapy is encouraged regardless of substance use status. Patients with substance use disorder are at risk of HCV reinfection after cure. Follow up viral load testing (FUVL) with HCV RNA is recommended. We investigated factors associated with adoption of FUVL in real-world clinical settings.

METHODS

Medical records of all patients with SUD who achieved HCV cure with direct acting antivirals at a multidisciplinary addiction treatment program between 2014 and 2019 were reviewed as part of a quality improvement initiative. Demographic and clinical characteristics including SUD treatment, urine toxicology results, and medical service use were collected. Factors associated with FUVL were analyzed and the rate of HCV reinfection was determined.

RESULTS

Among 149 patients, 58.4% received FUVL. Receipt of FUVL was associated with engagement in ongoing primary medical care after cure (AOR 4.39, 95% CI [1.67, 11.49]). The HCV reinfection rate among those who received FUVL was 1.95 per 100 person-years of follow up (95% CI [0.64, 5.98]). There was no significant difference in the percentage of negative urine toxicology results before and after cure.

CONCLUSIONS

Over half of a cohort of patients with substance use disorder cured of HCV received FUVL. The relationship between FUVL and engagement in primary medical and substance use treatment highlights the importance of integrated systems in providing longitudinal care for patients cured of HCV. Standardized interventions that facilitate FUVL testing and management of infectious complications of SUD in addiction treatment settings are needed.

Reinfection With the Hepatitis C Virus in Men Who Have Sex With Men After Successful Treatment With Direct-acting Antivirals in Germany: Current Incidence Rates, Compared With Rates During the Interferon Era

BACKGROUND

Micro-elimination of the hepatitis C virus (HCV) includes treatment in populations at risk of ongoing HCV transmission, such as men who have sex with men (MSM) or people who inject drugs (PWID). We analyzed the HCV reinfection incidence rates of participants in the German hepatitis C cohort (GECCO) and compared our data to previous findings from the interferon era.

METHODS

Patients with HCV reinfections in the multi-centric GECCO cohort were compared to patients in whom no reinfection occurred. The HCV reinfection incidence rate in MSM was also compared to the incidence rate in the interferon era (using data from the European Acquired Immunodeficiency Syndrome Treatment Network [NEAT]).

RESULTS

Between January 2014 and April 2018, 48 HCV reinfections occurred in 2298 individuals (2%), with 2346 cured HCV episodes. The median time to reinfection was 500 days (range 16-1160) and the overall HCV reinfection incidence rate was 1.89 per 100 person-years (py; 95% confidence interval [CI], 1.41-2.48). In a multivariate analysis, the transmission risk in MSM was the only independent risk factor of HCV reinfection (odds ratio, 39.3; 95% CI, 4.57-334.40; P = .001). The incidence rate in MSM was 9.02 (95% CI, 6.48-12.26) per 100 py, compared to 1.14 per 100 py in PWID (95% CI, .56-2.09). The incidence rate for a first HCV reinfection in MSM was similar in the direct-acting antiviral era, compared to the interferon era, with a hazard ratio of 1.05 (95% CI, .64-1.74; P = .831).

CONCLUSIONS

HCV reinfection remains a frequent finding among MSM in Germany. In addition to behavioral interventions, early HCV treatment and retreatment should be implemented for this subgroup to prevent HCV transmission.

Adherence to Direct-Acting Antiviral Therapy in People Actively Using Drugs and Alcohol: The INCLUD Study

BACKGROUND

Hepatitis C virus treatment in persons who use drugs (PWUD) is often withheld due to adherence and reinfection concerns. In this study, we report treatment outcomes, technology-based adherence data, and adherence predictors in PWUD and/or alcohol.

METHODS

INCLUD was a prospective, open-label study of ledipasvir/sofosbuvir for 12 weeks in PWUD aged 18-70 years. Participants were randomized to wireless (wirelessly observed therapy) or video-based directly observed therapy (vDOT). Drug use was assessed every 2 weeks. Sustained virologic response (SVR) was examined by intention-to-treat and as-treated. Factors associated with missing ≥1 dose(s) between visits were examined using generalized linear models.

RESULTS

Sixty participants received ≥1 ledipasvir/sofosbuvir dose (47 human immunodeficiency virus [HIV]/hepatitis C virus [HCV], 13 HCV only; 78% male; 22% black; 25% cirrhotic). Substance use occurred at 94% of person-visits: 60% marijuana, 56% alcohol, 37% methamphetamine, 22% opioids, 17% cocaine, and 20% injection drug use. The SVR by intention-to-treat was 86.7% (52 of 60) and as-treated was 94.5% (52 of 55). Confirmed failures included 1 relapse, 1 reinfection, and 1 unknown (suspected reinfection). Median total adherence was 96% (interquartile range [IQR], 85%-100%; range, 30%-101%), and between-visit adherence was 100% (IQR, 86%-100%; range, 0%-107%). The odds of missing ≥1 dose between visits increased with HIV coinfection (2.94; 95% confidence interval [CI], 1.37-6.32; P = .006), black race (4.09; 95% CI, 1.42-11.74; P = .009), methamphetamine use (2.51; 95% CI, 1.44-4.37; P = .0.001), and cocaine use (2.12; 95% CI, 1.08-4.18; P = .03) and decreased with marijuana use (0.34; 95% CI, 0.17-0.70; P = .003) and vDOT (0.43; 95% CI, 0.21-0.87; P = .02).

CONCLUSIONS

Persons who use drugs achieved high SVR rates with high, but variable, ledipasvir/sofosbuvir adherence using technology-based methods. These findings support efforts to expand HCV treatment in PWUD.

Toward microelimination of hepatitis C and HIV coinfection in NHS Tayside, Scotland: Real-world outcomes

BACKGROUND AND AIMS

NHS Tayside is a health board in Scotland which serves around 400 000 residents. Approximately, 2761 are estimated to be persons who inject drugs (PWID), and therefore at risk of infections such as hepatitis C (HCV) and HIV. There are few studies exploring mechanisms and success of eliminating HCV in HIV co-infected PWID using real-world data. This study aims to empirically assess HCV treatment outcomes in people living with HIV (PLHIV) to evaluate progress toward microelimination of HCV in the HIV-positive population in Tayside.

METHODS

HCV testing and treatment details for PLHIV stored on clinical databases dating from 2001 were extracted and anonymized. HCV treatment uptake among co-infected patients eligible for HCV treatment was calculated. Reinfection incidence was calculated in person years. Confidence intervals were calculated assuming Poisson distribution. Caldicott Guardian approval was obtained to access patient data (ref: IGTCAL 5677).

RESULTS

Ninety-six percent of PLHIV were tested for HCV across nine services and aware of their HCV status. From 2001 to 2019, 58 PLHIV were HCV co-infected. Four left the area and five died prior to HCV treatment. Forty-nine were eligible for HCV treatment. Thirty were treated with PEGylated interferon (Peg-IFN); 18 with direct acting antivirals (DAA). One is yet to be treated. Twelve treated with Peg-IFN did not achieve sustained viral response (SVR12); 10 were retreated, two died prior to re-treatment. Injecting drug use was the mode of HCV transmission for 39 of 49 patients. Proportion who achieved SVR12 is 75%; 92% if treated with DAAs. Annual proportions of PLHIV treated for HCV increased from 3.57% in the Peg-IFN era to 66.67% in the DAA era. Reinfection incidence is 0.2 per 100 person years (CI -0.3 to 0.7).

CONCLUSIONS

NHS Tayside has made progress toward microelimination of HCV among PLHIV. The most common mode of HCV transmission in PLHIV in NHS Tayside is injecting drug use. DAAs increased the proportion of co-infected PLHIV treated for HCV and produced superior SVR12 results compared to Peg-IFN.

Hepatitis C Reinfection in People Who Inject Drugs in Resource-Limited Countries: A Systematic Review and Analysis

Hepatitis C (HCV) is a global pandemic. The World Health Organization has developed a strategic plan for HCV elimination that focuses on low- and middle-income countries (LMICs) and high-risk populations, including people who inject drugs (PWID). While direct-acting antiviral (DAA) therapies are highly effective at eliminating HCV infections and have few side effects, medical professionals and policymakers remain concerned about the risk of reinfection among PWID. This study is a systematic review of research measuring the rate of HCV reinfection among PWID in LMICs and identifies additional areas for further research. A systematic search strategy was used to identify studies documenting HCV reinfection after sustained virologic response in PWID in LMICs. We refined results to include studies where at least 50% of participants had DAA treatment for primary HCV infection. Pooled reinfection rate was calculated across all studies. Seven studies met eligibility criteria. Most studies were conducted in six upper middle-income countries (Mexico, Romania, Russia, Taiwan, Georgi, and Brazil) and one lower middle-income country (Bangladesh) with a total of 7665 participants. No study included information from PWID in low-income countries. Sample sizes ranged from 200 to 3004 individuals, with demographic data missing for most participants. Four studies used deep gene sequencing, and reflex genotyping procedures to differentiate reinfection (infection by a different HCV genotype/subtype) from virologic relapse (infection by the same strain). The follow-up time of people cured from primary chronic HCV infection ranged from 12 weeks to 6.6 years. The pooled reinfection rate of all seven studies was 2.8 (range: 0.02 to 10.5) cases per 100 person-years (PY). In the five studies that differentiated relapse from reinfection, the incidence of reinfection was 1.0 per 100 PY. To date, research on reinfection rates among PWID in LMICs remains limited. Research focused on PWID in low-income countries is particularly needed to inform clinical decision making and evidence-based programs. While rates of reinfection among PWID who complete DAA treatment in upper and lower middle-income countries were similar or lower than rates observed in PWID in high-income countries, the rates were highly variable and factors may influence the accuracy of these measurements. This systematic review identifies several areas for continued research. Policies concerning access to HCV testing and treatment should be comprehensive and not place restrictions on PWID in these settings.

Impact of comprehensive care on health care use among a cohort of marginalized people living with hepatitis C in Toronto

Background: The majority of new hepatitis C (HCV) cases occur among people who inject drugs. In recent years, multidisciplinary models of HCV treatment have emerged that demonstrate successful treatment outcomes for this population, as well as broad positive individual- and system-level impacts. Our objective was to evaluate changes in health care use among a cohort of people living with HCV before and after engagement with one such program. Methods: Program data were uniquely linked to provincial health administrative databases. Rates of emergency department (ED) visits and hospital admissions of clients from 2011 through 2015 ( N = 103) were evaluated using linkages with administrative data for the 2 years before and after program initiation. Data were evaluated using negative binomial regression models with a covariance structure to account for within-individual correlations. Results: Of participants, 72.8% were men (mean age 47 years), and 38% experienced high rates of physical and mental health comorbidity (Aggregated Diagnosis Group score ≥10). Female clients had significantly fewer ED visits 2 years after program initiation (5.04 versus 3.12; risk ratio [RR] 0.61 [95% CI 0.44% to 0.86%]). ED visits for infectious diseases and soft tissue injury were significantly lower for the cohort overall (RRs 0.58 0.51 [95% CIs 0.35% to 0.95% and 0.29% to 0.90%], respectively). Conclusion: Co-locating HCV treatment within comprehensive primary care and harm reduction services appears to have benefits beyond HCV, including a reduction in ED visits among women and a decrease in ED visits for soft tissue infections for all participants.

Impact of comprehensive care on health care use among a cohort of marginalized people living with hepatitis C in Toronto

Background: The majority of new hepatitis C (HCV) cases occur among people who inject drugs. In recent years, multidisciplinary models of HCV treatment have emerged that demonstrate successful treatment outcomes for this population, as well as broad positive individual- and system-level impacts. Our objective was to evaluate changes in health care use among a cohort of people living with HCV before and after engagement with one such program. Methods: Program data were uniquely linked to provincial health administrative databases. Rates of emergency department (ED) visits and hospital admissions of clients from 2011 through 2015 ( N = 103) were evaluated using linkages with administrative data for the 2 years before and after program initiation. Data were evaluated using negative binomial regression models with a covariance structure to account for within-individual correlations. Results: Of participants, 72.8% were men (mean age 47 years), and 38% experienced high rates of physical and mental health comorbidity (Aggregated Diagnosis Group score ≥10). Female clients had significantly fewer ED visits 2 years after program initiation (5.04 versus 3.12; risk ratio [RR] 0.61 [95% CI 0.44% to 0.86%]). ED visits for infectious diseases and soft tissue injury were significantly lower for the cohort overall (RRs 0.58 0.51 [95% CIs 0.35% to 0.95% and 0.29% to 0.90%], respectively). Conclusion: Co-locating HCV treatment within comprehensive primary care and harm reduction services appears to have benefits beyond HCV, including a reduction in ED visits among women and a decrease in ED visits for soft tissue infections for all participants.

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.

Economic Evaluation of Hepatitis C Treatment Extension to Acute Infection and Early-Stage Fibrosis Among Patients Who Inject Drugs in Developing Countries: A Case of China

We aimed to assess the cost-effectiveness of (1) treating acute hepatitis C virus (HCV) vs. deferring treatment until the chronic phase and (2) treating all chronic patients vs. only those with advanced fibrosis; among Chinese genotype 1b treatment-naïve patients who injected drugs (PWID), using a combination Daclatasvir (DCV) plus Asunaprevir (ASV) regimen and a Peg-interferon (PegIFN)-based regimen, respectively. A decision-analytical model including the risk of HCV reinfection simulated lifetime costs and quality-adjusted life-years (QALYs) of three treatment timings, under the DCV+ASV and PegIFN regimen, respectively: Treating acute infection (“Treat at acute”), treating chronic patients of all fibrosis stages (“Treat at F0 (no fibrosis)”), treating only advanced-stage fibrosis patients (“Treat at F3 (numerous septa without cirrhosis)”). Incremental cost-effectiveness ratios (ICERs) were used to compare scenarios. “Treat at acute” compared with “Treat at F0” was cost-saving (cost: DCV+ASV regimen—US$14,486.975 vs. US$16,224.250; PegIFN-based regimen—US$19,734.794 vs. US$22,101.584) and more effective (QALY: DCV+ASV regimen—14.573 vs. 14.566; PegIFN-based regimen—14.148 vs. 14.116). Compared with “Treat at F3”; “Treat at F0” exhibited an ICER of US$3780.20/QALY and US$15,145.98/QALY under the DCV+ASV regimen and PegIFN-based regimen; respectively. Treatment of acute HCV infection was highly cost-effective and cost-saving compared with deferring treatment to the chronic stage; for both DCV+ASV and PegIFN-based regimens. Early treatment for chronic patients with DCV+ASV regimen was highly cost-effective.

Hepatitis C Virus Treatment Status and Barriers among Patients in Methadone Maintenance Treatment Clinics in Guangdong Province, China: A Cross-Sectional, Observational Study

We aimed to evaluate the status and barriers related to hepatitis C virus (HCV) treatment among Chinese methadone maintenance treatment (MMT) clients, and the willingness and barriers of patients to accept directly observed treatment (DOT) service and oral direct-acting antivirals (DAAs). We conducted a cross-sectional survey from July to October 2017 in Guangdong Province, China, involving 678 HCV antibody-positive MMT patients. If they reported being infected with HCV, then their HCV treatment experience, willingness to use DOT and DAAs, along with any barriers, were collected. Logistic regression analysis was used to identify the correlates of initiating HCV treatment. Among those reporting HCV infection (54%, 366/678), 39% (144/366) initiated treatment; however, 38% (55/144) interrupted and 55% (79/135) delayed treatment for 15 months. Seventy-five percent (273/366) and 53% (195/366) were willing to use DOT and DAAs, respectively. Unaffordable medical costs and insignificant symptoms were the major barriers to HCV treatment and accepting DOT or DAAs. The lack of a stable residence, being a woman, and having ever injected drugs were all associated with a low probability of initiating treatment (p < 0.05). This study highlights a limited uptake of HCV treatment among MMT patients, and a need to strengthen the popularity of DOT and DAAs and integrate them into Chinese MMT clinics.

HCV reinfections after viral clearance among HIV-positive patients with recent HCV infection in Taiwan

BACKGROUND

Higher rates of hepatitis C virus (HCV) reinfection after viral clearance have been well described among HIV-positive men who have sex with men (MSM) in Europe. The epidemiology of HCV reinfection, however, has rarely been investigated among HIV-positive patients in Asia-Pacific region.

METHODS

We retrospectively identified HIV-positive patients with recent HCV infection who had cleared their primary infection, either spontaneously or via treatment, between January 2011 and May 2018. All included patients were observed until 31 March 2019. HCV reinfection was defined as recurrent HCV viraemia after achieving viral clearance with anti-HCV treatment or after spontaneous clearance.

RESULTS

During the study period, 219 HIV-positive patients (90.4% MSM) were diagnosed with recent HCV infection. Viral clearance with successful treatment was achieved in 108 patients (49.3%) and spontaneous clearance occurred in 20 (9.1%); of them, 18 (14.1%) acquired HCV reinfections, resulting in an incidence rate of 8.2 per 100 person-years of follow-up (95% CI 5.2-13.1). With the adjusted Cox proportional hazards model, we found a higher reinfection risk in patients with syphilis (adjusted hazard ratio 10.3, 95% CI 1.4-77.8, P = .023) compared to those without syphilis. HCV RNA testing, if performed only following syphilis and elevated aminotransferases, might miss 44.4% and 33.3% of HCV reinfections, respectively.

CONCLUSIONS

Similar to the findings in Europe, we observed a high incidence of HCV reinfection among HIV-positive Taiwanese with recent HCV infection, which was significantly associated with syphilis. To identify HCV reinfections, annual HCV RNA testing should be instituted instead of testing driven by symptoms, syphilis or elevated aminotransferases.

Direct-acting antiviral treatment for hepatitis C, reinfection and mortality among people attending an inner-city community health centre in Victoria, Canada

BACKGROUND

Direct-acting antiviral (DAA) treatment for hepatitis C virus (HCV) has been shown to be effective among PWID, but more real-world data on treatment outcomes is needed. The aim of this analysis was to assess the efficacy of DAA therapy, and the rate of reinfection and mortality among people attending an inner-city community health centre in Victoria, Canada.

METHODS

In this retrospective study, patients treated with DAA therapy between November 2014 and Dec 31, 2017 were included. Retrospective chart review was performed to assess recent injecting drug use (IDU, previous six months) or receipt of opioid agonist treatment (OAT). The primary endpoint was Sustained Virologic Response (SVR12). Secondary endpoints included HCV reinfection and mortality.

RESULTS

Of 270 patients who initiated DAA treatment (31% female), 20% (n=54) had HIV/HCV coinfection, 32% (n=84) had cirrhosis, 67% (n=181) had genotype 1, 6% (n=15) had genotype 2, 26% (n=69) had genotype 3. 46% (n=125) of patients were receiving OAT and 49% (n=132) reported recent IDU. 98% (n=265) completed treatment; two people stopped due to mental health, two people died, and one was non-adherent. 92% (249 of 270) achieved SVR12. 16 patients with End of Treatment (EOT) response did not have a SVR12; 7 were lost to follow-up; 2 people refused bloodwork; 2 people died; 1 had reinfection; and 4 had viral relapse. There was no difference in SVR12 by OAT (OAT, 93% vs. no OAT, 91%, P=0.435), recent injecting drug use (yes, 92% vs. no, 92%, P=0.904), or HIV status (HIV, 92% vs. no HIV, 94%, P=0.498). Eight cases of HCV reinfection were observed over 253 person-years of follow up (3.2 cases per 100 person-years; 95% CI 1.6-6.3). Twenty people died (6.3 per 100 person-years; 95% CI 3.9-10.3), including two during therapy (drug overdose, n=2) and 18 following therapy completion (drug overdose, n=7).

CONCLUSION

This study demonstrates that DAA treatment is effective among a marginalized population receiving care in an inner-city community health centre. The high mortality in this study highlights the importance of integrating HCV care within a framework addressing drug-related harms, preventing overdose mortality, addressing social inequalities, and improving the health of PWID.

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.

Reinfection by hepatitis C virus following effective all-oral direct-acting antiviral drug therapy in HIV/hepatitis C virus coinfected individuals

OBJECTIVES

We analysed hepatitis C virus (HCV) reinfection among participants in a prospective registry of HIV/HCV-coinfected patients treated with all-oral direct-acting antiretroviral (DAA)-based therapy in the region of Madrid.

DESIGN

An observational cohort study.

METHODS

The study period started on the date sustained viral response (SVR) was confirmed. The censoring date was 31 December 2017. SVR was defined as negative HCV-RNA 12 weeks after completion of treatment. Reinfection was defined as a positive HCV-RNA test result after achievement of SVR.

RESULTS

Reinfections were detected in 17 of 2359 HIV/HCV-coinfected patients (0.72%) overall, in 12 out of 177 (6.78%) MSM and in five out of 1459 (0.34%) people who inject drugs (PWID). The incidence of reinfection [95% confidence interval (95% CI)] per 100 person-years was 0.48 (0.30-0.77) overall, 5.93 (3.37-10.44) for MSM and 0.21 (0.09-0.52) for PWID. Reinfections were detected a median of 15 weeks (interquartile range 13-26) after SVR. In 10 (58.82%) patients, the reinfection was caused by a different HCV genotype. All 12 MSM with reinfection acknowledged unprotected anal intercourse with several partners, seven used chemsex, six reported fisting and four practiced slamming. A concomitant STI was detected in five patients. Four IDU with reinfection reported injecting drugs following SVR.

CONCLUSION

HCV reinfection is a matter of concern in HIV-positive MSM treated with all-oral DAA therapy in the region of Madrid. Our data suggest that prevention strategies and frequent testing with HCV-RNA should be applied following SVR in MSM who engage in high-risk practices.