Opioid substitution therapy protects against hepatitis C virus acquisition in people who inject drugs: the HITS-c study

Scale-up of Direct-Acting Antiviral Treatment in Prisons Is Both Cost-effective and Key to Hepatitis C Virus Elimination

Background

The Surveillance and Treatment of Prisoners With Hepatitis C (SToP-C) study demonstrated that scaling up of direct-acting antiviral (DAA) treatment reduced hepatitis C virus (HCV) transmission. We evaluated the cost-effectiveness of scaling up HCV treatment in statewide prison services incorporating long-term outcomes across custodial and community settings.

Methods

A dynamic model of incarceration and HCV transmission among people who inject drugs (PWID) in New South Wales, Australia, was extended to include former PWID and those with long-term HCV progression. Using Australian costing data, we estimated the cost-effectiveness of scaling up HCV treatment in prisons by 44% (as achieved by the SToP-C study) for 10 years (2021-2030) before reducing to baseline levels, compared to a status quo scenario. The mean incremental cost-effectiveness ratio (ICER) was estimated by comparing the differences in costs and quality-adjusted life-years (QALYs) between the scale-up and status quo scenarios over 40 years (2021-2060) discounted at 5% per annum. Univariate and probabilistic sensitivity analyses were performed.

Results

Scaling up HCV treatment in the statewide prison service is projected to be cost-effective with a mean ICER of A$12 968/QALY gained. The base-case scenario gains 275 QALYs over 40 years at a net incremental cost of A$3.6 million. Excluding DAA pharmaceutical costs, the mean ICER is reduced to A$6 054/QALY. At the willingness-to-pay threshold of A$50 000/QALY, 100% of simulations are cost-effective at various discount rates, time horizons, and changes of treatment levels in prison and community.

Conclusions

Scaling up HCV testing and treatment in prisons is highly cost-effective and should be considered a priority in the national elimination strategy.

Clinical Trials Registration

NCT02064049.

A Harm Reduction Framework for Integrated Treatment of Co-Occurring Opioid Use Disorder and Trauma-Related Disorders

The opioid epidemic has exposed a gulf in mental health research, treatment, and policy: Most patients with comorbid trauma-related disorder (TRD) and opioid use disorder (OUD) (TRD + OUD) remain undiagnosed or unsuccessfully treated for the combination of TRD symptoms and opioid use. TRD treatments tend to be psychotherapies that are not accessible or practical for many individuals with TRD + OUD, due to TRD treatment models not systematically incorporating principles of harm reduction (HR). HR practices prioritize flexibility and unequivocally improve outcomes and save lives in the treatment of OUD. Considering the urgent need to improve TRD + OUD treatment and outcomes, we propose that the OUD and TRD fields can be meaningfully reconciled by integrating HR principles with classic phasic treatment for TRD. Adding a "prestabilization" phase of treatment for TRD - largely analogous to the precontemplation Stage of Change - creates opportunities to advance research, clinical practice, and policies and potentially improve patient outcomes.

Comprehensive needle and syringe program and opioid agonist therapy reduce HIV and hepatitis c virus acquisition among people who inject drugs in different settings: A pooled analysis of emulated trials

BACKGROUND AND AIMS

Although the Netherlands, Canada and Australia were early adopters of harm reduction for people who inject drugs (PWID), their respective HIV and hepatitis C (HCV) epidemics differ. We measured the pooled effect of needle and syringe program (NSP) and opioid agonist therapy (OAT) participation on HIV and HCV incidence in these settings.

DESIGN

For each cohort, we emulated the design and statistical analysis of a target trial using observational data.

SETTING AND PARTICIPANTS

We included PWID at risk of HIV or HCV infection from the Amsterdam Cohort Studies (1985-2013), Vancouver Injection Drug Users Study (1997-2009) and Melbourne Injecting Drug User Cohort Study (SuperMIX) (2010-2021).

MEASUREMENTS

Separately for each infection and cohort (only HCV in SuperMIX), marginal structural models were used to compare the effect of comprehensive (on OAT and 100% NSP coverage or on OAT only if no recent injection drug use) versus no/partial NSP/OAT (no OAT and/or <100% NSP coverage) participation. Pooled hazard ratios (HR) and 95% CI were calculated using random-effects meta-analysis.

FINDINGS

We observed 94 HIV seroconversions and 81 HCV seroconversions among 2023 and 430 participants, respectively. Comprehensive NSP/OAT led to a 41% lower risk of HIV acquisition (pooled HR = 0.59, 95% CI = 0.36-0.96) and a 76% lower risk of HCV acquisition (pooled HR = 0.24, 95% CI = 0.11-0.51), compared with no/partial NSP/OAT, with little heterogeneity between studies for both infections (I2  = 0%).

CONCLUSIONS

In the Netherlands, Canada and Australia, comprehensive needle and syringe program and opioid agonist therapy participation appears to substantially reduce HIV and hepatitis C acquisition compared with no or partial needle and syringe program/opioid agonist therapy participation. These findings from an emulated trial design reinforce the critical role of comprehensive access to harm reduction in optimizing infection prevention for people who inject drugs.

Incidence of HIV and hepatitis C virus among people who inject drugs, and associations with age and sex or gender: a global systematic review and meta-analysis

BACKGROUND

Measuring the incidence of HIV and hepatitis C virus (HCV) infection among people who inject drugs (PWID) is key to track progress towards elimination. We aimed to summarise global data on HIV and primary HCV incidence among PWID and associations with age and sex or gender.

METHODS

In this systematic review and meta-analysis, we updated an existing database of HIV and HCV incidence studies among PWID by searching MEDLINE, Embase, and PsycINFO, capturing studies published between Jan 1, 2000, and Dec 12, 2022, with no language or study design restrictions. We contacted authors of identified studies for unpublished or updated data. We included studies that estimated incidence by longitudinally re-testing people at risk of infection or by using assays for recent infection. We pooled incidence and relative risk (RR; young [generally defined as ≤25 years] vs older PWID; women vs men) estimates using random-effects meta-analysis and assessed risk of bias with a modified Newcastle-Ottawa scale. This study is registered with PROSPERO, CRD42020220884.

FINDINGS

Our updated search identified 9493 publications, of which 211 were eligible for full-text review. An additional 377 full-text records from our existing database and five records identified through cross-referencing were assessed. Including 28 unpublished records, 125 records met the inclusion criteria. We identified 64 estimates of HIV incidence (30 from high-income countries [HICs] and 34 from low-income or middle-income countries [LMICs]) and 66 estimates of HCV incidence (52 from HICs and 14 from LMICs). 41 (64%) of 64 HIV and 42 (64%) of 66 HCV estimates were from single cities rather than being multi-city or nationwide. Estimates were measured over 1987-2021 for HIV and 1992-2021 for HCV. Pooled HIV incidence was 1·7 per 100 person-years (95% CI 1·3-2·3; I2=98·4%) and pooled HCV incidence was 12·1 per 100 person-years (10·0-14·6; I2=97·2%). Young PWID had a greater risk of HIV (RR 1·5, 95% CI 1·2-1·8; I2=66·9%) and HCV (1·5, 1·3-1·8; I2=70·6%) acquisition than older PWID. Women had a greater risk of HIV (RR 1·4, 95% CI 1·1-1·6; I2=55·3%) and HCV (1·2, 1·1-1·3; I2=43·3%) acquisition than men. For both HIV and HCV, the median risk-of-bias score was 6 (IQR 6-7), indicating moderate risk.

INTERPRETATION

Although sparse, available HIV and HCV incidence estimates offer insights into global levels of HIV and HCV transmission among PWID. Intensified efforts are needed to keep track of the HIV and HCV epidemics among PWID and to expand access to age-appropriate and gender-appropriate prevention services that serve young PWID and women who inject drugs.

FUNDING

Canadian Institutes of Health Research, Fonds de recherche du Québec-Santé, Canadian Network on Hepatitis C, UK National Institute for Health and Care Research, and WHO.

Stimulant use among patients in opioid treatment settings: Provider perspectives

INTRODUCTION

Methadone maintenance therapy (MMT) has been a pillar of opioid addiction treatment. Opioid treatment programs (OTPs) have been faced with an escalating threat of stimulant use and related overdose deaths among patients. We know little about how providers currently address stimulant use while maintaining treatment for opioid use disorder.

METHODS

We conducted 5 focus groups with 36 providers (n = 11 prescribers; 25 behavioral health staff), and collected an additional 46 surveys (n = 7 prescribers; 12 administrators; 27 behavioral health staff). Questions focused on perceptions of patient stimulant use and interventions. We applied inductive analysis to identify themes relevant to identification of stimulant use, use trends, intervention approaches, and perceived needs to improve care.

RESULTS

Providers indicated a trend of rising stimulant use among patients, especially those experiencing homelessness or comorbid health conditions. They reported a range of approaches to patient screening and intervention, including medication and harm reduction, improving treatment engagement, increasing level of care, and providing incentives. Providers expressed less agreement as to which of these interventions were effective, and though providers saw stimulant use as a common and severe problem, they reported little problem recognition and interest in treatment from their patients. A particular concern of providers was the prevalence and danger of synthetic opioids, such as fentanyl. They sought more research and resources to identify effective interventions and medications to address these issues. Also notable was an interest in contingency management (CM) and use of reinforcements/rewards to encourage stimulant use reduction.

CONCLUSION

Providers face challenges in treating patients who use both opioids and stimulants. Although methadone is available to treat opioid use, no such "silver bullet" exists for stimulant use disorder. The rise in stimulant and synthetic opioid (e.g., fentanyl) combination products is presenting an extraordinary challenge for providers whose patients are at unprecedented risk for overdose. Providing OTPs with more resources to address polysubstance use is critical. Existing research indicates strong support for CM in OTPs, but providers reported regulatory and financial barriers to implementation. Further research should develop effective interventions that are accessible to providers in OTPs.

Prison-based interventions are key to achieving HCV elimination among people who inject drugs in New South Wales, Australia: A modelling study

BACKGROUND & AIMS

People who inject drugs (PWID) experience high incarceration rates which are associated with increased hepatitis C virus (HCV) transmission risk. We assess the importance of prison-based interventions for achieving HCV elimination among PWID in New South Wales (NSW), Australia.

METHODS

A model of incarceration and HCV transmission among PWID was calibrated in a Bayesian framework to epidemiological and incarceration data from NSW, incorporating elevated HCV acquisition risk among recently released PWID. We projected the contribution of differences in transmission risk during/following incarceration to HCV transmission over 2020-2029. We estimated the past and potential future impact of prison-based opioid agonist therapy (OAT; ~33% coverage) and HCV treatment (1500 treatments in 2019 with 32.9%-83.3% among PWID) on HCV transmission. We estimated the time until HCV incidence reduces by 80% (WHO elimination target) compared to 2016 levels with or without prison-based interventions.

RESULTS

Over 2020-2029, incarceration will contribute 23.0% (17.9-30.5) of new HCV infections. If prison-based interventions had not been implemented since 2010, HCV incidence in 2020 would have been 29.7% (95% credibility interval: 22.4-36.1) higher. If current prison and community HCV treatment rates continue, there is an 98.8% probability that elimination targets will be achieved by 2030, with this decreasing to 10.1% without current prison-based interventions.

CONCLUSIONS

Existing prison-based interventions in NSW are critical components of strategies to reduce HCV incidence among PWID. Prison-based interventions are likely to be pivotal for achieving HCV elimination targets among PWID by 2030.

Incidence of primary hepatitis C virus infection among people who inject drugs in Australia pre- and post-unrestricted availability of direct acting antiviral therapies

AIMS

The 2016 Global Health Sector Strategy (GHSS) on viral hepatitis aims to reduce new hepatitis C virus (HCV) infections by 80% by 2030, including a 30% reduction by 2020. This study aimed to estimate primary HCV incident infection among a national sample of people who inject drugs (PWID) before and after the introduction of unrestricted access to HCV direct-acting antiviral (DAA) therapy via Australia's Pharmaceutical Benefits Scheme in 2016.

DESIGN

A simple deterministic linkage method identified repeat respondents in serial cross-sectional surveys conducted among PWID. Two separate retrospective cohorts of HCV antibody-negative respondents were created, corresponding to the pre- (2010-15) and post- (2016-21) DAA time-periods.

SETTING AND PARTICIPANTS

This study took place in Australia. Among 757 PWID retained (376 pre-DAA, 381 post-DAA), more than half were male (60%), the majority were heterosexual (80%), the median age was 40 years (interquartile range = 33-46 years) and the predominant drugs last injected were heroin (24%), pharmaceutical opioids (27%) and methamphetamine (41%).

MEASUREMENTS

The primary outcome was HCV seroconversion, defined as a negative HCV antibody test result followed by a positive HCV antibody result. Time to primary incident HCV infection was estimated using the person-years (PY) method.

FINDINGS

A total 97 of 376 (2010-15) and 41 of 381 (2016-21) HCV seroconversions were identified. Primary HCV incidence more than halved, from 13.6 per 100 PY [95% confidence intervals (CI) = 11.2, 16.6] in 2010-15 to 5.4 per 100 PY (95% CI = 3.9, 7.3) in 2016-21. The decline was independent of observed differences in demographic and drug use characteristics over the two time-periods (adjusted hazard ratio = 0.47, 95% CI = 0.31-0.69, P < 0.001).

CONCLUSIONS

Australia has had a 53% reduction in primary hepatitis C virus (HCV) incidence among people who inject drugs following unrestricted availability of HCV direct acting antiviral therapy in March 2016. Given that PWID are the predominant population at risk of HCV infection in Australia, findings add to the evidence that Australia has probably met its 2020 Global Health Sector Strategy subtarget of a 30% decline in new infections.

Identification of human progenitors of exhausted CD8+ T cells associated with elevated IFN-γ response in early phase of viral infection

T cell exhaustion is a hallmark of hepatitis C virus (HCV) infection and limits protective immunity in chronic viral infections and cancer. Limited knowledge exists of the initial viral and immune dynamics that characterise exhaustion in humans. We studied longitudinal blood samples from a unique cohort of individuals with primary infection using single-cell multi-omics to identify the functions and phenotypes of HCV-specific CD8⁺ T cells. Early elevated IFN-γ response against the transmitted virus is associated with the rate of immune escape, larger clonal expansion, and early onset of exhaustion. Irrespective of disease outcome, we find heterogeneous subsets of progenitors of exhaustion, based on the level of PD-1 expression and loss of AP-1 transcription factors. Intra-clonal analysis shows distinct trajectories with multiple fates and evolutionary plasticity of precursor cells. These findings challenge the current paradigm on the contribution of CD8⁺ T cells to HCV disease outcome and provide data for future studies on T cell differentiation in human infections.

Health service utilisation and access for people who inject drugs during COVID-19

INTRODUCTION

The wide-spread implementation of interventions to limit transmission and public health consequences of COVID-19 in the Australian state of Victoria had flow-on consequences for people who use and inject drugs. Consequences included the interruption of illicit drug supply and drug procurement, and the disruption to the delivery of health services. To inform strategies that can minimise the adverse outcomes of similar future disruptive events, this study explored how COVID-19 restrictions impacted access to harm reduction and drug treatment services for people who inject drugs in Melbourne, Victoria.

METHODS

Qualitative semi-structured interviews were conducted via an online calling app, with 11 participants of a broader cohort study (the SuperMIX study) in April 2020. Interviews were focused on participants experiences of accessing and using harm reduction and drug treatment services. Data were thematically analysed using a process of blended coding.

RESULTS

Findings revealed how disruptions in the delivery of harm reduction and drug treatment services-in response to COVID-19 restrictions-created barriers accessing sterile injecting equipment, increased risk of arrest by police and exacerbated social isolation. Participants reported difficulties adapting to changes in services access, with some increases in injecting risk behaviours. However, improvements in opioid agonist therapy prescriptions were noted as a beneficial outcome.

DISCUSSION

By examining the impacts of COVID-19 and the resultant restrictions on people who inject drugs' access to health services in Melbourne, Victoria, findings provide guidance for future responses to the unanticipated large-scale effects of the COVID-19 pandemic, and similar disruptive events.

Addressing injecting related risks among people who inject both opioids and stimulants: Findings from an Australian survey of people who inject drugs

Background

Opioids and stimulants are the most commonly injected illicit drugs worldwide and in Australia. While some people who inject drugs (PWID) prefer either opioids or stimulants, others regularly use both opioids and stimulants. Limited available research indicates that those who use opioids and stimulants together, either in combination or alternating between the two, may engage in injection-related practices which potentially place them at greater health risk and could lead to poorer health outcomes.

Methods

Participants were recruited nationally through member organizations of the Australian Injecting and Illicit Drug Users League (AIVL); these organizations represent PWID in each Australian state and territory. This study compared a sample of PWID (N = 535) who reported past-month injection of opioids only (N = 173), stimulants only (N = 208), or both (N = 154) on a range of health and wellbeing outcomes. PWID completed a survey assessing drugs injected, frequency of injecting, receptive equipment sharing, psychological distress, self-reported hepatitis C (HCV) status, experienced and internalized stigma, drug use salience, and community attachment.

Results

People who injected both opioids and stimulants reported more frequent injecting, more experiences of stigma, and greater reported HCV diagnosis than people who injected stimulants or opioids alone. They also showed greater attachment to a community of PWID and greater salience of drug use to their identity.

Conclusions

The findings of increased injecting and broader harms associated with injecting both stimulants and opioids are important for tailoring harm reduction and intervention designs for people who use both opioid and stimulant drugs, including prioritizing peer-based approaches.

Availability of opioid agonist treatment and critical incidents in Forensic Clinics for Dependency Diseases in Germany

BACKGROUND

Prevalence of substance use disorders, especially opioid use disorders, is high in patients admitted into forensic psychiatric settings. Opioid agonist treatment is a safe, well-established, and effective treatment option for patients that suffer from opioid dependence. Surprisingly, data on the availability and practice of opioid agonist treatment (OAT) options in German Forensic Clinics for Dependency Diseases is rare. Furthermore, essential data on the prevalence of critical incidents such as violent behavior, relapse, or escape from the clinic are missing for this particular treatment setting.

MATERIALS AND METHODS

We conducted an observational study on all forensic addiction treatment units in Germany (Sect. 64 of the German Criminal Code). A questionnaire on the availability and practice of OAT was sent to all Forensic Clinics for Dependency Diseases in Germany. Following items were assessed: availability and the total number of patients that received an OAT in 2018, available medication options, specific reasons for start and end of OAT, number of treatments terminated without success, number of successful treatments, and critical incidents such as violent behavior, relapse, escape and reoffending. We compared the forensic clinics that offered OAT with those that did not offer this treatment option. The data were analyzed descriptively. Mean and standard deviation was calculated for metric scaled variables. For categorical variables, absolute and relative frequencies were calculated. The two groups (OAT vs. Non-OAT institutions) were compared concerning the given variables by either using Fishers exact test (categorical variables), t-test (normally distributed metric variables), or Wilcoxon-test (metric variables not normally distributed).

RESULTS

In total, 15 of 46 Forensic Clinics for Dependency Diseases participated in the study (33%). In total, 2,483 patients were treated in the participating clinics, 18% were relocated into prison due to treatment termination, and 15% were discharged successfully in 2018. 275 critical incidents were reported: violence against a patient (4%), violence against staff (1.6%), escape (4.7%) and reoffending in (0.5%). In seven clinics treating 1,153 patients, an OAT was available. OAT options in forensic clinics were buprenorphine/naloxone, buprenorphine, methadone, and levomethadone. Regarding critical incidents and successful discharge, no differences were detected in the clinics with or without an OAT. In the clinics that offered an OAT, we found a significantly higher rate of treatment termination without success (p < 0.007) in comparison to clinics without an OAT program. Ninety-nine patients received an OAT, and this treatment was ended due to illegal drug abuse (57%), refusal to give a urine drug sample (71%), and cases where the OAT was given away to other patients (85%).

CONCLUSION

In Forensic Clinics for Dependency Diseases in Germany, OAT is not available in every institution, and thus, access is limited. Critical incidents such as violent behavior against staff or patients and escape are not uncommon in these forensic treatment settings. Further studies are needed to enhance the understanding of OAT practice and the risks for patients and staff.

Hepatitis C virus cascade of care among people who inject drugs in Australia: Factors associated with testing and treatment in a universal healthcare system

BACKGROUND

Understanding factors associated with engagement across the hepatitis C virus (HCV) cascade of care (CoC) among people who inject drugs (PWID) is critical for developing targeted interventions to enhance engagement and further HCV elimination efforts. We describe the CoC among Australian PWID, and identify factors associated with engagement at each stage.

METHODS

As part of the 2018 and 2019 Illicit Drug Reporting System, Australians who regularly inject drugs reported lifetime HCV antibody and RNA testing, treatment uptake and completion. Multivariable logistic regression identified characteristics associated with outcomes.

RESULTS

Of 1499 participants, 87% reported antibody testing. Of those, 70% reported RNA testing, of whom 60% reported being RNA positive. Among those, 76% reported initiating treatment, 78% of whom completed. Incarceration history (adjusted odds ratio 1.90; 95% confidence interval 1.28-2.82), current opioid agonist treatment (OAT) (1.99; 1.14-3.47), and recent alcohol and other drug (AOD) counselling (2.22; 1.27-3.88) were associated with antibody testing. Incarceration history (1.42; 1.07-1.87), and current OAT (2.07; 1.51-2.86) were associated with RNA testing. Current OAT (1.92; 1.22-3.03) and recent AOD counselling (1.91; 1.16-3.13) were associated with treatment uptake. Methamphetamine as drug injected most often in the last month was associated with reduced odds of antibody (0.41; 0.25-0.66) and RNA testing (0.54; 0.40-0.74), compared to heroin.

CONCLUSION

CoC engagement amongst Australian PWID is encouraging, with AOD service engagement associated with testing and treatment. Further efforts to reach those not service engaged, particularly those not receiving OAT or who predominantly inject methamphetamine, are needed to achieve HCV elimination targets.

Video directly observed therapy for patients receiving office-based buprenorphine - A pilot randomized controlled trial

BACKGROUND

We conducted a pilot study to assess feasibility of using video directly-observed therapy (DOT) for patients initiating buprenorphine to evaluate whether it is associated with better opioid use disorder (OUD) outcomes when compared to treatment-as-usual (TAU).

METHODS

Pilot randomized controlled trial of adult patients with OUD initiating buprenorphine treatment (n = 78) at two sites (Seattle, WA and Boston, MA) from January 2019 to May 2020. Intervention was video DOT using a HIPAA-compliant smartphone application to record taking daily buprenorphine. Study smartphones, text reminders to upload a video, and calendar summaries of video DOT adherence were provided. Main outcomes were 1) percentage of 12 weekly urine drug tests (UDT) negative for illicit opioids and 2) engagement in treatment at week 12 (i.e., having an active prescription for buprenorphine within the last 7 days).

RESULTS

Of 78 enrolled, 20 (26 %) were female; 29 (37 %) non-white; and 31 (40 %) homeless. The mean (standard deviation) percentage of doses confirmed by video was 31 % (34 %). In intention-to-treat analysis, the average percentage of weekly opioid negative UDT was 50 % (95 % CI: 40-63 %) in the intervention arm versus 64 % (95 % CI: 55-74 %) among controls; RR = 0.78 (95 % CI: 0.60-1.02, p = 0.07). Engagement at week 12 was 69 % (95 % CI: 56-86 %) v. 82 % (95 % CI: 71-95 %) in the intervention vs. TAU arms, respectively; RR = 0.84 (95 % CI: 0.65-1.10, p = 0.20).

CONCLUSIONS

The video DOT intervention did not result in improvements in illicit opioid use and treatment engagement compared to TAU. The study was limited by low rates of intervention use.

TRIAL REGISTRATION

ClinicalTrails.gov, NCT03779997, Registered on December 19, 2018.

Injecting frequency trajectories and hepatitis C virus acquisition: Findings from a cohort of people who inject drugs in Montréal, Canada

BACKGROUND

Frequent injecting increases hepatitis C (HCV) acquisition risk among people who inject drugs (PWID). However, few studies have examined how temporal fluctuations in injecting frequency may effect HCV infection risk. Thus, this study examined HCV incidence according to injecting frequency trajectories followed by PWID over one year in Montréal, Canada.

METHODS

At three-month intervals from March 2011 to June 2016, HCV-uninfected PWID (never infected or cleared infection) enrolled in the Hepatitis Cohort (HEPCO) completed interviewer-administered questionnaires and HCV testing. At each visit, participants reported the number of injecting days (0-30 days) for each of the past three months. In previous work, using group-based trajectory modeling, we identified five injecting frequency trajectories followed by participants over one year (months 1-12 of follow-up), including sporadic, infrequent, increasing, decreasing, and frequent injecting. In this study, we estimated group-specific HCV incidence (months 1-63 of follow-up) using posterior probabilities to assign participants to their most likely trajectory group.

RESULTS

Of 386 participants (mean age=40, 82% male, 48% never HCV-infected), 72 acquired HCV during 893 person-years of follow-up. HCV incidence for the whole study sample was 8.1 per 100 person-years (95%CI=6.4-10.1). Trajectory group-specific HCV incidences were highest for those injecting drugs with decreasing (23.9, 14.4-37.5) or increasing frequency (16.0, 10.1-24.3), intermediate for those injecting at consistently high frequency (10.2, 5.4-17.8), and lowest for those injecting infrequently (3.9, 2.2-6.5) or sporadically (4.3, 2.2-7.6).

CONCLUSION

Results suggest that PWID at highest HCV risk are those injecting at high frequency, either transitorily (increasing, decreasing injecting) or consistently (frequent injecting). This study highlights changes in injecting frequency as a potentially important dimension to consider among the factors leading to HCV acquisition. Clinical and public health interventions tailored to PWID with different injecting frequency profiles may contribute to HCV prevention.

Estimating the number of new hepatitis C infections in Australia in 2015, prior to the scale-up of direct-acting antiviral treatment

BACKGROUND AND AIM

The recent downward revision of the estimated number of people living with chronic hepatitis C in Australia means that the annual number of new hepatitis C infections should also be revised. We aimed to estimate the annual number of new hepatitis C infections among people who inject drugs (PWID) in Australia in 2015, prior to the introduction of direct-acting antiviral (DAA) treatment for hepatitis C, as an updated baseline measure for assessing the impact of DAAs on hepatitis C incidence over the next 10 years.

METHODS

A systematic review identified articles estimating hepatitis C incidence rates among PWID between 2002 and 2015. Reported incidence rates were adjusted to account for unrepresentative needle and syringe program (NSP) coverage among study participants compared with PWID overall. The total number of PWID in Australia and the hepatitis C RNA prevalence among PWID were taken from published estimates. The annual number of new infections was estimated by multiplying the pooled NSP coverage-adjusted incidence rate by the number of susceptible PWID in 2015.

RESULTS

Five studies were included, with unadjusted incidence rates ranging from 7.6 to 12.8 per 100 person-years. The overall pooled incidence rate (after adjusting for NSP coverage) was 9.9 per 100 person-years (95% confidence interval: 8.3-11.8). This led to an estimate of 4126 (range 2499-6405) new hepatitis C infections in 2015.

CONCLUSIONS

Our updated estimate provides an important baseline for evaluating the impact of hepatitis C elimination efforts and can be used to validate outcomes of future modeling studies.

The impact of current opioid agonist therapy on hepatitis C virus treatment initiation among people who use drugs from in the DAA era: A population-based study

BACKGROUND

Evidence that opioid agonist therapy (OAT) is associated with increased odds of hepatitis C virus (HCV) treatment initiation among people who use drugs (PWUD) is emerging. The objective of this study was to determine the association between current OAT and HCV treatment initiation among PWUD in a population-level linked administrative dataset.

METHODS

The British Columbia (BC) Hepatitis Testers Cohort was used for this study, which includes all people tested for or diagnosed with HCV in BC, linked to medical visits, hospitalizations, laboratory, prescription drug, and mortality data from 1992 until 2019. PWUD with injecting drug use or opioid use disorder and chronic HCV infection were identified for inclusion in this study. HCV treatment initiation was the main outcome, and subdistribution proportional hazards modeling was used to assess the relationship with current OAT.

RESULTS

13,803 PWUD with chronic HCV were included in this study. Among those currently on OAT at the end of the study period, 47% (2,704/5,770) had started HCV treatment, whereas 22% (1778/8033) of those not currently on OAT has started HCV treatment .. Among PWUD with chronic HCV infection, current OAT was associated with higher likelihood of HCV treatment initiation in time to event analysis (adjusted hazard ratio 1.84 [95%CI, 1.50, 2.26]).

CONCLUSIONS

Current OAT was associated with a higher likelihood of HCV treatment initiation. However, many PWUD with HCV currently receiving OAT have yet to receive HCV treatment. Enhanced integration between substance use care and HCV treatment is needed to improve the overall health of PWUD.

Buprenorphine utilization among all Washington State residents' based upon prescription monitoring program data - Characteristics associated with two measures of retention and patterns of care over time

BACKGROUND

Opioid use disorder is a serious health condition for which buprenorphine is proven effective, yet providers substantially underutilize buprenorphine. We present two approaches to measuring treatment duration, factors associated with retention, and patterns of care.

METHODS

The study determined incident buprenorphine prescribing for all Washingtonians utilizing prescription monitoring program data from 2012 to 2019. The study calculated episode of care and cumulative time in care. Generalized linear models estimated associations among the length of the first episode of care and cumulative time in care with sex, age, and rurality. Cox proportional hazards models estimated the time to discontinuing buprenorphine for the first four episodes of care and time to discontinuing the last episode of care.

RESULTS

Mean and median duration of the first episode were 320 and 84 days, respectively, and for cumulative time in care 308 and 195 days. A minority of peoples' first episodes exceeded 180 days (37%). Being female and older were significantly associated with longer first episodes and cumulative time in care. Survival analyses indicated that the proportion of those still in care at 6, 12, and 24 months into their first episode of care declined for those with more than one episode of care; conversely the study found much smaller differences in retention for the last episode of care, indicating that many people were eventually able to be retained in care for longer periods of time.

CONCLUSION

Episodes of care and cumulative time on buprenorphine were both short compared to minimum quality recommendations of 180 days. Median cumulative time in care was double that of the first episode, highlighting that many people engage in subsequent episodes of substantial length. Episode of care and cumulative care analyses should inform states, payers, health care systems and providers in measuring and setting treatment duration goals.

Prevalence and Medication Treatment of Opioid Use Disorder Among Primary Care Patients with Hepatitis C and HIV

BACKGROUND

Hepatitis C and HIV are associated with opioid use disorders (OUD) and injection drug use. Medications for OUD can prevent the spread of HCV and HIV.

OBJECTIVE

To describe the prevalence of documented OUD, as well as receipt of office-based medication treatment, among primary care patients with HCV or HIV.

DESIGN

Retrospective observational cohort study using electronic health record and insurance data.

PARTICIPANTS

Adults ≥ 18 years with ≥ 2 visits to primary care during the study (2014-2016) at 6 healthcare systems across five states (CO, CA, OR, WA, and MN).

MAIN MEASURES

The primary outcome was the diagnosis of OUD; the secondary outcome was OUD treatment with buprenorphine or oral/injectable naltrexone. Prevalence of OUD and OUD treatment was calculated across four groups: HCV only; HIV only; HCV and HIV; and neither HCV nor HIV. In addition, adjusted odds ratios (AOR) of OUD treatment associated with HCV and HIV (separately) were estimated, adjusting for age, gender, race/ethnicity, and site.

KEY RESULTS

The sample included 1,368,604 persons, of whom 10,042 had HCV, 5821 HIV, and 422 both. The prevalence of diagnosed OUD varied across groups: 11.9% (95% CI: 11.3%, 12.5%) for those with HCV; 1.6% (1.3%, 2.0%) for those with HIV; 8.8% (6.2%, 11.9%) for those with both; and 0.92% (0.91%, 0.94%) among those with neither. Among those with diagnosed OUD, the prevalence of OUD medication treatment was 20.9%, 16.0%, 10.8%, and 22.3%, for those with HCV, HIV, both, and neither, respectively. HCV was not associated with OUD treatment (AOR = 1.03; 0.88, 1.21), whereas patients with HIV had a lower probability of OUD treatment (AOR = 0.43; 0.26, 0.72).

CONCLUSIONS

Among patients receiving primary care, those diagnosed with HCV and HIV were more likely to have documented OUD than those without. Patients with HIV were less likely to have documented medication treatment for OUD.

Treatment trajectories and barriers in opioid agonist therapy for people who inject drugs in rural Puerto Rico

BACKGROUND

Research has shown medication for opioid use disorder (MOUD) to have positive effects, including reducing HIV and HCV transmission, but important barriers to access remain among people who inject drugs (PWID). Barriers include lack of social and familial support, bureaucracy, distance to treatment, poverty, and homelessness. However, we know little about how these barriers interact with each other to shape PWID's drug treatment access and retention.

METHODS

We used qualitative methods with a dataset from a study conducted during 2019 with 31 active PWID residing in rural Puerto Rico. The study gathered ethnographic data and narratives about treatment trajectories to document the lived experiences of PWID as they moved in and out of treatment.

RESULTS

Participants were at least 18 years old; 87.7% were male, the mean age was 44.1 years, and the mean age at first injection was 22 years. Participants identified homelessness, lack of proper ID or other identifying documents, and previous negative experiences with MOUD as the main barriers to treatment entry and retention. In addition, PWID's belief that MOUD simply substitutes an illegal drug for a legal one, while furthering drug dependence by chronically subjecting patients to treatment, constitutes an additional barrier to entry. Findings from this study demonstrate that MOUD barriers to access and retention compound and are severely affected by poverty and other forms of vulnerability among PWID in rural Puerto Rico.

CONCLUSION

Policies to increase access and retention should consider barriers not in isolation but as an assemblage of many factors.

Adaptation of Oxford Nanopore technology for hepatitis C whole genome sequencing and identification of within-host viral variants

Background

Hepatitis C (HCV) and many other RNA viruses exist as rapidly mutating quasi-species populations in a single infected host. High throughput characterization of full genome, within-host variants is still not possible despite advances in next generation sequencing. This limitation constrains viral genomic studies that depend on accurate identification of hemi-genome or whole genome, within-host variants, especially those occurring at low frequencies. With the advent of third generation long read sequencing technologies, including Oxford Nanopore Technology (ONT) and PacBio platforms, this problem is potentially surmountable. ONT is particularly attractive in this regard due to the portable nature of the MinION sequencer, which makes real-time sequencing in remote and resource-limited locations possible. However, this technology (termed here ‘nanopore sequencing’) has a comparatively high technical error rate. The present study aimed to assess the utility, accuracy and cost-effectiveness of nanopore sequencing for HCV genomes. We also introduce a new bioinformatics tool (Nano-Q) to differentiate within-host variants from nanopore sequencing.

Results

The Nanopore platform, when the coverage exceeded 300 reads, generated comparable consensus sequences to Illumina sequencing. Using HCV Envelope plasmids (~ 1800 nt) mixed in known proportions, the capacity of nanopore sequencing to reliably identify variants with an abundance as low as 0.1% was demonstrated, provided the autologous reference sequence was available to identify the matching reads. Successful pooling and nanopore sequencing of 52 samples from patients with HCV infection demonstrated its cost effectiveness (AUD$ 43 per sample with nanopore sequencing versus $100 with paired-end short read technology). The Nano-Q tool successfully separated between-host sequences, including those from the same subtype, by bulk sorting and phylogenetic clustering without an autologous reference sequence (using only a subtype-specific generic reference). The pipeline also identified within-host viral variants and their abundance when the parameters were appropriately adjusted.

Conclusion

Cost effective HCV whole genome sequencing and within-host variant identification without haplotype reconstruction are potential advantages of nanopore sequencing.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-07460-1.

Incidence and factors associated with discontinuation of opioid agonist therapy among people who inject drugs in Australia

AIMS

To estimate incidence and predictors of opioid agonist therapy (OAT) discontinuation in a national cohort of people who inject drugs (PWID).

DESIGN AND SETTING

Annually repeated cross-sectional serosurveillance among PWID attending ~50 needle-syringe programmes across Australia.

PARTICIPANTS

Between 1995 and 2018, 2651 PWID who reported current OAT and had subsequent survey participation completed 6739 surveys. Respondents were followed over 11 984 person-years of observation (PYO). Respondents were predominantly male (60%), and the median age was 34 years. Heroin was the most commonly reported drug last injected (46%), and methadone was the most commonly prescribed OAT (77%).

MEASUREMENTS

The primary outcome was discontinuation of OAT (methadone, buprenorphine or buprenorphine-naloxone). Among respondents who reported current OAT, those who did not report current OAT in all subsequent records were defined as discontinued, and those with current OAT at all subsequent records were defined as retained. Predictors of discontinuation included self-reported demographic (sex, location, Indigenous status) and drug use characteristics (drug last injected, frequency of injection).

FINDINGS

Just fewer than one-third of respondents (29%) reported an OAT discontinuation event. The crude discontinuation rate was 6.3 [95% confidence intervals (CI) = 5.9-6.8] per 100 PYO. Discontinuation was significantly higher among respondents who reported last injecting pharmaceutical opioids [adjusted hazard ratio (aHR) = 1.75, 95% CI = 1.41-2.17, P < 0.001], being prescribed buprenorphine (aHR = 1.44, 95% CI = 1.18-1.76, P = 0.001) or buprenorphine-naloxone (aHR = 1.68, 95% CI = 1.20-2.34, P = 0.002), daily or more frequent injection (aHR = 1.51, 95% CI = 1.23-1.85, P < 0.001), recent public injecting (aHR = 1.37, 95% CI = 1.17-1.60, P < 0.001), incarceration in the previous 12 months (aHR = 1.31, 95% CI = 1.05-1.64, P = 0.017), recent receptive syringe or injection equipment sharing (aHR = 1.28, 95% CI = 1.10-1.48, P = 0.001) and male sex (aHR = 1.27, 95% CI = 1.09-1.47, P = 0.002).

CONCLUSION

People who inject drugs attending needle-syringe programmes in Australia appear to be significantly more likely to discontinue opioid agonist treatment if they were prescribed buprenorphine or buprenorphine-naloxone compared with methadone, are male or report injection risk behaviours and recent incarceration.

Sex Discrepancies in the Protective Effect of Opioid Agonist Therapy on Incident Hepatitis C Infection

BACKGROUND

While opioid agonist therapy (OAT) reduces the risk of hepatitis C virus (HCV) acquisition among people who inject drugs (PWID), protective effects may be attenuated in females. We used pooled data from an international collaboration of prospective cohorts to assess sex disparities in HCV incidence among PWID exposed to OAT.

METHODS

Independent predictors of HCV infection were identified using Cox regression models with random effects after accounting for the clustering effect of study sites. Unadjusted and adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) are presented in sex-specific analyses.

RESULTS

Among 701 participants exposed to OAT, HCV incidence was 16.5/100 person-years of observation (PYO) (95% CI, 13.1-20.7) in females and 7.6/100 PYO (95% CI, 6.0-9.5) in males (female:male adjusted HR [aHR], 1.80 [95% CI, 1.37-2.22]; P < .001). Factors associated with HCV acquisition among females exposed to OAT included nonwhite race (aHR, 1.79 [95% CI, 1.25-2.56]; P = .001), unstable housing (aHR, 4.00 [95% CI, 3.62-4.41]; P < .001), daily or more frequent injection (aHR, 1.45 [95% CI, 1.01-2.08]; P = .042), and receptive syringe sharing (aHR, 1.43 [95% CI, 1.33-1.53]; P < .001).

CONCLUSIONS

Female PWID exposed to OAT are twice as likely as their male counterparts to acquire HCV. While there is a need for better understanding of sex differences in immune function and opioid pharmacokinetic and pharmacodynamic parameters, structural and behavioral interventions that target women are required to bolster the efficacy of OAT in preventing HCV transmission.

Hepatitis C Virus Prevalence and Incidence in a Large Nationwide Sample of Patients in Opioid Substitution Treatment in Germany: A Prospective Cohort Study

BACKGROUND

Hepatitis C virus (HCV) infection is highly prevalent among people who inject drugs (PWID). Accurate data on HCV prevalence and incidence rates among patients receiving opioid substitution treatment (OST) are needed to estimate the current and future burden of HCV infections in this high-risk population.

METHODS

Baseline data from routine care were collected between October 2014 and June 2016 from randomly selected OST facilities in Germany. The primary outcome measure was the HCV status (antibody and RNA prevalence). Patients who were HCV antibody-negative at baseline were followed up after 12 months to calculate the HCV incidence rate.

RESULTS

Sixty-three facilities from 14 German Federal States provided clinical data for a total of 2466 OST patients. HCV antibody and HCV RNA prevalence were 58.8% (95% confidence interval [CI], 56.8%-60.8%) and 27.3% (95% CI, 25.5%-29.2%), respectively. At baseline, a total of 528 patients (21.4%) had previously undergone antiviral treatment. Moreover, lower HCV RNA prevalence was associated with female gender, employment, younger age, and shorter duration of OST and opioid dependence. The HCV incidence rate was 2.5 cases per 100 person-years.

CONCLUSIONS

The low HCV RNA prevalence and HCV incidence rates confirm that OST in Germany is an effective setting both for treating chronic HCV infections and for preventing new infections among PWID. Scaling up the provision of OST, HCV testing, and HCV treatment among OST patients are important public health strategies for reducing HCV infections in this high-risk population.

Understanding concurrent stimulant use among people on methadone: A qualitative study

INTRODUCTION AND AIMS

Opioid-related overdoses are an epidemic in North America, prompting a greater use of medications for opioid use disorder, such as methadone. Although many people work toward overall drug abstinence while on methadone, a sub-population of people with and without histories of polysubstance use engage in stimulant use while on methadone treatment. This study explores motivations for concurrent stimulant and methadone use in a street-involved drug-using population.

DESIGN AND METHODS

Semi-structured qualitative interviews were conducted with 39 people on methadone in Vancouver, Canada. Participants were recruited from among the participants in two community-based prospective cohort studies consisting of HIV-positive and HIV-negative people who use drugs. Interview transcripts were analysed using an inductive and iterative approach.

RESULTS

Our analysis identified three primary themes. First, participants articulated how stimulants were used to counter the sedating effects of methadone and enable them to engage in daily and survival activities (e.g. income generation). Second, participants described increased stimulant use to compensate for reduced stimulant intoxication while taking methadone. Finally, participants described the desire to achieve intoxication on stimulants once stable on methadone, as their substance use treatment goals did not involve drug abstinence.

DISCUSSION AND CONCLUSION

Among a street-involved drug-using population in which people do not have abstinence-based treatment goals, there are several functional reasons to use stimulants concurrently while on methadone. A deeper and more nuanced understanding of substance use motivators may contribute to further research and inform policy and guideline changes that support low threshold and harm reduction-focused methadone treatment programs and other interventions to reduce drug-related harms.

Video directly observed therapy intervention using a mobile health application among opioid use disorder patients receiving office-based buprenorphine treatment: protocol for a pilot randomized controlled trial

BACKGROUND

Office-based buprenorphine treatment of opioid use disorder (OUD) does not typically include in-person directly observed therapy (DOT), potentially leading to non-adherence. Video DOT technologies may safeguard against this issue and thus enhance likelihood of treatment success. We describe the rationale and protocol for the Trial of Adherence Application for Buprenorphine treatment (TAAB) study, a pilot randomized controlled trial (RCT) to evaluate the effects of video DOT delivered via a smartphone app on office-based buprenorphine treatment outcomes, namely illicit opioid use and retention.

METHODS

Participants will be recruited from office-based opioid addiction treatment programs in outpatient clinics at two urban medical centers and randomized to either video DOT (intervention) delivered via a HIPAA-compliant, asynchronous, mobile health (mHealth) technology platform, or treatment-as-usual (control). Eligibility criteria are: 18 years or older, prescribed sublingual buprenorphine for a cumulative total of 28 days or less from the office-based opioid treatment program, and able to read and understand English. Patients will be considered ineligible if they are unable or unwilling to use the intervention, provide consent, or complete weekly study visits. All participants will complete 13 in-person weekly visits and be followed via electronic health record data capture at 12- and 24-weeks post-randomization. Data gathered include the following: demographics; current and previous treatment for OUD; self-reported diversion of prescribed buprenorphine; status of their mental and physical health; and self-reported lifetime and past 30-day illicit substance use. Participants provide urine samples at each weekly visit to test for illicit drugs and buprenorphine. The primary outcome is percentage of weekly urines that are negative for opioids over the 12-weeks. The secondary outcome is engagement in treatment at week 12.

DISCUSSION

Video DOT delivered through mHealth technology platform offers possibility of improving patients' buprenorphine adherence by providing additional structure and accountability. The TAAB study will provide important preliminary estimates of the impact of this mHealth technology for patients initiating buprenorphine, as well as the feasibility of study procedures, thus paving the way for further research to assess feasibility and generate preliminary data for design of a future Phase III trial. Trial Registration ClinicalTrails.gov, NCT03779997, Registered on December 19, 2018.

Estimating the Consensus hepatitis C Cascade of Care among people who inject drugs in Australia: Pre and post availability of direct acting antiviral therapy

Background Monitoring the hepatitis C virus (HCV) cascade of care (CoC) among people who inject drugs (PWID) is an essential component of the response to World Health Organisation's (WHO) hepatitis elimination goals. This study aimed to estimate the Consensus hepatitis C CoC among PWID using data collected in Australia prior to and after the introduction of unrestricted direct-acting antiviral (DAA) therapy in March 2016. Methods The Australian Needle Syringe Program Survey is a cross-sectional bio-behavioural surveillance system that recruits >2000 PWID annually. Using data from 2015 and 2019, HCV antibody and ribonucleic acid (RNA) test results from dried blood spots were combined with self-reported data on HCV diagnostic testing and treatment to project HCV Consensus CoC indicators at a population-level among Australian PWID. Results Among an estimated 75,000 people who inject drugs on a regular basis in Australia, the number with active HCV infection declined from 32,619 (44%) in October 2015 to 12,679 (17%) in October 2019. The majority (78% in 2015 and 2019) of PWID reported HCV diagnosis, while the proportion of those diagnosed who were treated increased from 3% in 2015 to 47% in 2019. Among those treated, the proportion who were HCV RNA negative and assumed to have been successfully treated (cured), increased from 27% in 2015 to 88% in 2019. Conclusion This study demonstrates remarkable HCV CoC progress among PWID in Australia following availability of DAA therapy. There was a substantial increase in the proportion of HCV diagnosed PWID who initiated treatment and were cured, while the number of PWID with active HCV infection more than halved over a 3.5 year period. Estimates of the Consensus hepatitis C CoC among PWID is required to monitor progress toward WHO HCV elimination goals.

Identification and Management of Opioid Use Disorder in Primary Care: an Update

PURPOSE OF REVIEW

The rising prevalence of opioid use disorder (OUD) and related complications in North America coupled with limited numbers of specialists in addiction medicine has led to large gaps in treatment. Primary care providers (PCPs) are ideally suited to diagnose and care for people with OUD and are increasingly being called upon to improve access to care. This review will highlight the recent literature pertaining to the care of patients with OUD by PCPs.

RECENT FINDINGS

The prevalence of patients with OUD in primary care practice is increasing, and models of office-based opioid treatment (OBOT) are evolving to meet local needs of both ambulatory practices and patients. OBOT has been shown to increase access to care and demonstrates comparable outcomes when compared to more specialty-driven care. OBOT is an effective means of increasing access to care for patients with OUD. The ideal structure of OBOT depends on local factors. Future research must explore ways to increase the identification and diagnosis of patients with OUD, improve treatment retention rates, reduce stigma, and promote interdisciplinary approaches to care.

B cell immunodominance in primary hepatitis C virus infection

BACKGROUND & AIMS

Neutralising antibodies (NAbs) play a key role in clearance of HCV. NAbs have been isolated and mapped to several domains on the HCV envelope proteins. However, the immunodominance of these epitopes in HCV infection remains unknown, hindering efforts to elicit optimal epitope-specific responses. Furthermore, it remains unclear which epitope-specific responses are associated with broad NAb (bNAb) activity in primary HCV infection. The aim of this study was to define B cell immunodominance in primary HCV, and its implications on neutralisation breadth and clearance.

METHODS

Using samples from 168 patients with primary HCV infection, the antibody responses targeted 2 immunodominant domains, termed domains B and C. Genotype 1 and 3 infections were associated with responses targeted towards different bNAb domains.

RESULTS

No epitopes were uniquely targeted by clearers compared to those who developed chronic infection. Samples with bNAb activity were enriched for multi-specific responses directed towards the epitopes antigenic region 3, antigenic region 4, and domain D, and did not target non-neutralising domains.

CONCLUSIONS

This study outlines for the first time a clear NAb immunodominance profile in primary HCV infection, and indicates that it is influenced by the infecting virus. It also highlights the need for a vaccination strategy to induce multi-specific responses that do not target non-neutralising domains.

LAY SUMMARY

Neutralising antibodies will likely form a key component of a protective hepatitis C virus vaccine. In this work we characterise the predominant neutralising and non-neutralising antibody (epitope) targets in acute hepatitis C virus infection. We have defined the natural hierarchy of epitope immunodominance, and demonstrated that viral genotype can impact on this hierarchy. Our findings highlight key epitopes that are associated with broadly neutralising antibodies, and the deleterious impact of mounting a response towards some of these domains on neutralising breadth. These findings should guide future efforts to design immunogens aimed at generating neutralising antibodies with a vaccine candidate.

Prevalence of Opioid Dependence and Opioid Agonist Treatment in the Berlin Custodial Setting: A Cross-Sectional Study

BACKGROUND

Among people living in detention, substance use is highly prevalent, including opioid dependence. Opioid agonist treatment (OAT) has been established as an evidence-based, first-line treatment for opioid dependence. Despite high prevalence of opioid dependence, conclusive data regarding its prevalence and the OAT practice in German prisons is scarce; rather, the existing data widely diverges concerning the rates of people in detention receiving OAT.

MATERIALS AND METHODS

We conducted a cross-sectional survey of all detention facilities in Berlin. On the date of data collection, a full census of the routine records was completed based on the medical documentation system. For each opioid dependent individual, we extracted sociodemographic data (i.e., age, sex, and non-/German nationality, whether people experienced language-related communication barriers), information about OAT, comorbidities (HIV, hepatitis C, schizophrenia), and the detention center, as well as the anticipated imprisonment duration and sentence type. The data was first analyzed descriptively and secondly in an evaluative-analytical manner by analyzing factors that influence the access to OAT of people living in detention.

RESULTS

Among the 4,038 people in detention in the Berlin custodial setting under investigation, we identified a 16% prevalence of opioid dependence. Of the opioid-dependent individuals, 42% received OAT; 31% were treated with methadone, 55% were treated with levomethadone, and 14% were treated with buprenorphine. Access to OAT seemed mainly dependent upon initial receipt of OAT at the time of imprisonment, detention duration, the prisons in which individuals were detained, German nationality, and sex. The overall prevalence of HIV was 4-8%, hepatitis C was 31-42%, and schizophrenia was 5%.

CONCLUSIONS

The prevalence of opioid dependence and access to OAT remains a major health issue in the custodial setting. OAT implementation must be especially intensified among male, non-German, opioid-dependent individuals with a short detention period. Treatment itself must be diversified regarding the substances used for OAT, and institutional treatment differences suggest the need for a consistent treatment approach and the standardized implementation of treatment guidelines within local prison's standard operating procedures. Testing for infectious diseases should be intensified among opioid-dependent people living in detention to address scarcely known infection statuses and high infection rates.

Association between methamphetamine use and retention among patients with opioid use disorders treated with buprenorphine

BACKGROUND

Methamphetamine use is increasing in parts of the U.S., yet its impact on treatment for opioid use disorder is relatively unknown.

METHODS

The study utilized data on adult patients receiving buprenorphine from Washington State Medication Assisted Treatment-Prescription Drug and Opioid Addiction program clinics between November 1, 2015 and April 31, 2018. Past 30-day substance use data were collected at baseline and 6-months, as well as date of program discharge. Cox proportional hazards regression was used to estimate the relative hazards for treatment discharge comparing methamphetamine users at baseline with non-users, adjusting for site, time period, age, gender, race, ethnicity, and education. For a subset of patients with data, we describe the proportion of individuals reporting methamphetamine use at baseline versus 6-months.

RESULTS

The sample included 799 patients, of which 237 (30%) reported using methamphetamine in the past 30 days; of those, 156 (66%) reported 1-10 days of use, 46 (19%) reported 11-20 days of use, and 35 (15%) reported 21-30 days of use. Baseline methamphetamine use was associated with more than twice the relative hazards for discharge in adjusted models (aHR = 2.39; 95% CI: 1.94-2.93). In the sub-sample with data (n = 516), there was an absolute reduction of 15% in methamphetamine use: 135 (26%) reported use at baseline versus 57 (11%) at follow-up.

CONCLUSIONS

In summary, this study found that patients who concurrently used methamphetamine were less likely to be retained in buprenorphine treatment compared to non-users. For persons who were retained, however, methamphetamine use decreased over time.

Opioid Use Disorder Treatment Decision Making And Care Navigation Upon Release From Prison: A Feasibility Study

PURPOSE

Opioid use disorder (OUD) is a medical condition that is effectively treated with medications. A major challenge in breaking the cycle of OUD and related illegal activity is seamlessly introducing medications for opioid use disorder (MOUD) as individuals leave jail or prison. We examined the feasibility of a pilot intervention to link participants to ongoing MOUD and psychosocial supports following release from custody.

METHODS

The study enrolled adults with a history of OUD released from Washington State prisons to Department of Corrections (DOC) community supervision. Participants were randomized to the study intervention or comparison group. The intervention consisted of education on OUD and available treatments, support with individualized treatment decision making, and continued care navigation for 6 months to facilitate linkage to chosen treatments. Participants randomized to the control condition received referral to services in the community from their community corrections officers. A care navigation activity log documented intervention participants' intervention engagement, service utilization, and needs. Follow-up interviews were conducted at 1 and 6 months to assess satisfaction with the intervention.

RESULTS

Fifteen participants were enrolled. All were male, most were white (86.6%) and the average age was 36.9 years. The majority (14 of 15 participants) were near-daily heroin users with severe OUD prior to incarceration. Of the seven intervention participants, two wished to start medications immediately. Three participants reported starting buprenorphine or methadone in the subsequent follow-up period, with or without social support and/or outpatient counseling, and three reported enrolling in social support and/or outpatient counseling without medications. Participants who received the intervention reported high satisfaction. We discuss barriers and facilitators to study implementation.

CONCLUSION

An intervention to link participants to ongoing MOUD and psychosocial supports following release from prison had broad acceptability among participants and was feasible to implement among those recruited; however, enrollment was much lower than anticipated and the study intervention did not demonstrate the intended effect to facilitate use of MOUD immediately post-release in this small sample of participants. Given recent research showing benefits of pre-release medication initiation, the potential added benefits of this two-part intervention should be studied in systems that initiate MOUD prior to release.

Prevalence, estimated incidence, risk behaviours, and genotypic distribution of hepatitis C virus among people who inject drugs accessing harm-reduction services in Kenya: a retrospective cohort study

BACKGROUND

Sub-Saharan Africa has a large population of people with hepatitis C virus (HCV) infection, yet little is known about HCV among people who inject drugs this region. We assessed the prevalence of HCV mono-infection and HIV-HCV co-infection, and the estimated incidence, genotypes, and risk behaviours associated with HCV among people who inject drugs in Kenya.

METHODS

People aged 18 years or older who were living in Nairobi, coastal Kenya, or western Kenya, had a history of injection drug use, and had used any illicit drugs in the past 12 months were recruited at needle and syringe programme sites using respondent-driven sampling. Participants were screened for the presence of an anti-HCV antibody. Those who were anti-HCV positive underwent confirmatory HCV RNA testing, and those with detectable HCV RNA were genotyped. Participants were interviewed regarding parenteral risk behaviours and exposure to services received at the needle and syringe programme sites. We examined correlates of HCV infection and HIV-HCV co-infection using bivariate and multivariate regression, and estimated HCV incidence.

FINDINGS

Of 2188 enrolled participants, 291 (13%) were anti-HCV positive: 183 (22%) of 842 participants in coastal Kenya, 105 (13%) of 817 in Nairobi, and three (1%) of 529 in western Kenya. 284 anti-HCV-positive participants underwent successful HCV RNA testing, of whom 230 (81%) were viraemic. Estimated incidence rates of anti-HCV positivity per 100 person-years were 6·31 in coastal Kenya, 3·19 in Nairobi, and 0·22 in western Kenya. HCV incidence rate was greater in coastal Kenya compared with Nairobi (incidence rate ratio 1·97 [95% CI 1·35-2·93], p=0·0001) and the western region (28·17 [7·55-236·58], p<0·0001). In the coastal region, history of incarceration, more years injecting, more injections in the past month, and receptive cooker sharing were associated with increased risk of HCV, while female sex, more years injecting, more injections in the past month, and regular use of a syringe with a detachable needle were associated with HCV risk in Nairobi. HCV prevalence among HIV-positive participants was 50% (66 of 131 participants) in coastal Kenya, 35% (42 of 121) in Nairobi, and 4% (one of 23) in western Kenya. Risk factors for HIV-HCV co-infection were similar to those observed for HCV mono-infection. The prevailing genotypes were 1a (51%), 4a (47%), and mixed (2%; three 1a/4a and one 1a/2b).

INTERPRETATION

HCV prevalence, estimated incidence, and risk behaviours among people who inject drugs in Kenya vary with region, with the highest estimated incidence observed in coastal Kenya. These findings should be used to inform focused strategies to reduce HCV transmission, such as expansion of needle and syringe programmes, upscaling of opioid agonist therapy, and treatment as prevention in regions affected by injection drug use and HCV.

FUNDING

National Institute on Drug Abuse.

Clearance of hepatitis C virus is associated with early and potent but narrowly-directed, Envelope-specific antibodies

Hepatitis C virus (HCV) is one of very few viruses that are either naturally cleared, or alternatively persist to cause chronic disease. Viral diversity and escape, as well as host adaptive immune factors, are believed to control the outcome. To date, there is limited understanding of the critical, early host-pathogen interactions. The asymptomatic nature of early HCV infection generally prevents identification of the transmitted/founder (T/F) virus, and thus the study of host responses directed against the autologous T/F strain. In this study, 14 rare subjects identified from very early in infection (4–45 days) with varied disease outcomes (n = 7 clearers) were examined in regard to the timing, breadth, and magnitude of the neutralizing antibody (nAb) response, as well as evolution of the T/F strain. Clearance was associated with earlier onset and more potent nAb responses appearing at a mean of 71 days post-infection (DPI), but these responses were narrowly directed against the autologous T/F virus or closely related variants. In contrast, a delayed onset of nAbs (mean 425 DPI) was observed in chronic progressors that appear to have targeted longitudinal variants rather than the T/F strain. The nAb responses in the chronic progressors mapped to known CD81 binding epitopes, and were associated with rapid emergence of new viral variants with reduced CD81 binding. We propose that the prolonged period of viremia in the absence of nAbs in these subjects was associated with an increase in viral diversity, affording the virus greater options to escape nAb pressure once it emerged. These findings indicate that timing of the nAb response is essential for clearance. Further investigation of the specificities of the early nAbs and the factors regulating early induction of protective nAbs is needed.

Prevalence of and risk factors for hepatitis C virus antibody among people who inject drugs in Cambodia: a national biological and behavioral survey

BACKGROUND

Hepatitis C virus (HCV) is a significant global health concern. Despite evidence of the relationship between injecting drug use and HCV, studies on HCV among people who inject drugs in developing countries remain scarce. To address this need, we conducted this study to explore the prevalence of and factors associated with HCV antibody positivity among people who inject drugs in Cambodia.

METHODS

Data used for this study were collected as part of the National Integrated Biological and Behavioral Survey among people who use and inject drugs conducted in 2017. We used the respondent-driven sampling method to recruit participants in 12 provinces for face-to-face interviews and HIV and HCV antibody testing. Weighted multivariable logistic regression analysis was conducted to identify risk factors associated with HCV antibody positivity.

RESULTS

This study included 286 people who inject drugs with a mean age of 31.6 (SD = 7.5) years. The prevalence of HCV antibody among participants in this study was 30.4%, of whom 31.0% were co-infected with HIV. After adjustment for other covariates, the odds of HCV antibody positivity was significantly higher among participants who were in the older age group of 25 to 34 (AOR = 1.85, 95% CI = 1.06-7.92) and ≥ 35 (AOR = 2.67, 95% CI = 1.24-5.71), were in Vietnamese ethnic group (AOR = 5.44, 95% CI = 2.25-13.14), were living on the streets (AOR = 3.01, 95% CI = 1.29-704), had been sent to a drug rehabilitation center in the past 12 months (AOR = 2.67, 95% CI = 1.21-5.90), had received methadone maintenance therapy in the past 12 months (AOR = 3.02, 95% CI = 1.32-6.92), and were tested positive for HIV (AOR = 3.80, 95% CI = 1.58-9.12) compared to their respective reference group.

CONCLUSION

The prevalence of HCV antibody among people who inject drugs in Cambodia is high, particularly in older and more vulnerable subgroups. Tailor-made interventions are required to increase access to culturally sensitive harm reduction interventions to prevent primary HCV infection and reinfection. In addition, there is an opportunity to expand screening, diagnosis, and treatment with new directly acting antiviral agents.

Provider and patient perspectives on barriers to buprenorphine adherence and the acceptability of video directly observed therapy to enhance adherence

Background

Buprenorphine effectively reduces opioid craving and illicit opioid use. However, some patients may not take their medication as prescribed and thus experience suboptimal outcomes. The study aim was to qualitatively explore buprenorphine adherence and the acceptability of utilizing video directly observed therapy (VDOT) among patients and their providers in an office-based program.

Methods

Clinical providers (physicians and staff; n = 9) as well as patients (n = 11) were recruited from an office-based opioid treatment program at an urban academic medical center in the northwestern United States. Using a semi-structured guide, interviewers conducted individual interviews and focus group discussions. Interviews were digitally recorded and transcribed verbatim. Transcripts were independently coded to identify key themes related to non-adherence and then jointly reviewed in an iterative fashion to develop a set of content codes.

Results

Among providers and patients, perceived reasons for buprenorphine non-adherence generally fell into several thematic categories: social and structural factors that prevented patients from consistently accessing medications or taking them reliably (e.g., homelessness, transportation difficulties, chaotic lifestyles, and mental illness); refraining from taking medication in order to use illicit drugs or divert; and forgetting to take medication, especially in the setting of taking split-doses. Some participants perceived non-adherence to be less of a problem for buprenorphine than for other medications. VDOT was viewed as potentially enhancing patient accountability, leading to more trust from providers who are concerned about diversion. On the other hand, some participants expressed concern that VDOT would place undue burden on patients, which could have the opposite effect of eroding patient-provider trust. Others questioned the clinical indication.

Conclusions

Findings suggest potential arenas for enhancing buprenorphine adherence, although structural barriers will likely be most challenging to ameliorate. Providers as well as patients indicated mixed attitudes toward VDOT, suggesting it would need to be thoughtfully implemented.

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.

Understanding the Determinants of BnAb Induction in Acute HCV Infection

Despite recent advances in curative therapy, hepatitis C virus (HCV) still remains a global threat. In order to achieve global elimination, a prophylactic vaccine should be considered high priority. Previous immunogens used to induce broad neutralising antibodies (BnAbs) have been met with limited success. To improve immunogen design, factors associated with the early development of BnAbs in natural infection must first be understood. In this study, 43 subjects identified with acute HCV were analysed longitudinally using a panel of heterogeneous HCV pseudoparticles (HCVpp), to understand the emergence of BnAbs. Compared to those infected with a single genotype, early BnAb development was associated with subjects co-infected with at least 2 HCV subtypes during acute infection. In those that were mono-infected, BnAbs were seen to emerge with increasing viral persistence. If subjects acquired a secondary infection, nAb breadth was seen to boost upon viral re-exposure. Importantly, this data highlights the potential for multivalent and prime-boost vaccine strategies to induce BnAbs against HCV in humans. However, the data also indicate that the infecting genotype may influence the development of BnAbs. Therefore, the choice of antigen will need to be carefully considered in future vaccine trials.

6th Canadian Symposium on Hepatitis C Virus: Delivering a cure for hepatitis C infection—What are the remaining gaps?

Estimates are that more than 250,000 people in Canada are chronically infected with hepatitis C virus (HCV), and many more are unaware of their infection status. If untreated, chronic HCV infection can lead to cirrhosis and subsequent complications such as hepatocellular carcinoma. The Canadian Network on Hepatitis C, supported by the Public Health Agency of Canada and the Canadian Institutes of Health Research, has been committed to the scientific study of chronic hepatitis C and to supporting the advocacy work to improve diagnosis and access to HCV care in Canada. Although the treatment of HCV infection has been greatly advanced with direct-acting antivirals, with cure rates as high as 95%, many challenges remain in the implementation of HCV care. These issues include the lack of an effective vaccine, infection screening, treatment failure or resistance, post-cure health issues, limitations of treatment access despite increased provincial subsidization, complex needs of at-risk populations (ie, injection drug users, societal obstacles). At the 6th Canadian Symposium on HCV in March 2017, the theme “Delivering a Cure for Hepatitis C Infection: What Are the Remaining Gaps?” provided a framework in which basic scientists, clinicians, epidemiologists, social scientists, and community members interested in HCV research in Canada could showcase how they are working to address these ongoing challenges.

Management of acute HCV infection in the era of direct-acting antiviral therapy

The management of acute HCV infection has not been standardized following the availability of direct-acting antiviral agents (DAAs) for chronic HCV infection, and substantial uncertainty exists regarding the optimal treatment regimen and duration. Despite the lack of direct evidence, the 2016 American Association for the Study of Liver Diseases (AASLD)-Infectious Diseases Society of America (IDSA) guidelines supported "the same regimens for acute HCV as recommended for chronic HCV infection … owing to high efficacy and safety", whereas the 2016 European Association for the Study of the Liver (EASL) guidelines recommended sofosbuvir-ledipasvir, sofosbuvir-velpatasvir or sofosbuvir plus daclatasvir for 8 weeks in acute HCV infection, with a longer duration of 12 weeks recommended for those infected with HIV and/or baseline HCV RNA levels >1,000,000 IU/ml. This Review outlines the epidemiology, natural history and diagnosis of acute HCV infection and provides contemporary information on DAAs for acute and recent HCV infection. The Review also discusses the 2016 AASLD-IDSA and EASL recommendations for acute HCV infection management in light of available evidence and highlights key differences in study populations and design that influence interpretation. We focus on populations at high risk of HCV transmission and acquisition, including people who inject drugs and HIV-positive men who have sex with men, and highlight the potential effects of diagnosis and treatment of acute HCV infection in contributing to HCV elimination.

Impact of current and scaled-up levels of hepatitis C prevention and treatment interventions for people who inject drugs in three UK settings-what is required to achieve the WHO's HCV elimination targets?

AIMS

To estimate the impact of existing high-coverage needle and syringe provision (HCNSP, defined as obtaining more than one sterile needle and syringe per injection reported) and opioid substitution therapy (OST) on hepatitis C virus (HCV) transmission among people who inject drugs (PWID) in three UK settings and to determine required scale-up of interventions, including HCV treatment, needed to reach the World Health Organization (WHO) target of reducing HCV incidence by 90% by 2030.

DESIGN

HCV transmission modelling using UK empirical estimates for effect of OST and/or HCNSP on individual risk of HCV acquisition.

SETTING AND PARTICIPANTS

Three UK cities with varying chronic HCV prevalence (Bristol 45%, Dundee 26%, Walsall 19%), OST (72-81%) and HCNSP coverage (28-56%).

MEASUREMENTS

Relative change in new HCV infections throughout 2016-30 if current interventions were stopped. Scale-up of HCNSP, OST and HCV treatment required to achieve the WHO elimination target.

FINDINGS

Removing HCNSP or OST would increase the number of new HCV infections throughout 2016 to 2030 by 23-64 and 92-483%, respectively. Conversely, scaling-up these interventions to 80% coverage could achieve a 29 or 49% reduction in Bristol and Walsall, respectively, whereas Dundee may achieve a 90% decrease in incidence with current levels of intervention because of existing high levels of HCV treatment (47-58 treatments per 1000 PWID). If OST and HCNSP are scaled-up, Walsall and Bristol can achieve the same impact by treating 14 or 40 per 1000 PWID annually, respectively (currently two and nine treatments per 1000 PWID), while 18 and 43 treatments per 1000 PWID would be required if OST and HCNSP are not scaled-up.

CONCLUSIONS

Current opioid substitution therapy and high-coverage needle and syringe provision coverage is averting substantial hepatitis C transmission in the United Kingdom. Maintaining this coverage while getting current drug injectors onto treatment can reduce incidence by 90% by 2030.

Needle and syringe programmes and opioid substitution therapy for preventing HCV transmission among people who inject drugs: findings from a Cochrane Review and meta-analysis

AIMS

To estimate the effects of needle and syringe programmes (NSP) and opioid substitution therapy (OST), alone or in combination, for preventing acquisition of hepatitis C virus (HCV) in people who inject drugs (PWID).

METHODS

Systematic review and meta-analysis. Bibliographic databases were searched for studies measuring concurrent exposure to current OST (within the last 6 months) and/or NSP and HCV incidence among PWID. High NSP coverage was defined as regular NSP attendance or ≥ 100% coverage (receiving sufficient or greater number of needles and syringes per reported injecting frequency). Studies were assessed using the Cochrane risk of bias in non-randomized studies tool. Random-effects models were used in meta-analysis.

RESULTS

We identified 28 studies (n = 6279) in North America (13), United Kingdom (five), Europe (four), Australia (five) and China (one). Studies were at moderate (two), serious (17) critical (seven) and non-assessable risk of bias (two). Current OST is associated with 50% [risk ratio (RR) =0.50, 95% confidence interval (CI) = 0.40-0.63] reduction in HCV acquisition risk, consistent across region and with low heterogeneity (I2  = 0, P = 0.889). Weaker evidence was found for high NSP coverage (RR = 0.79, 95% CI = 0.39-1.61) with high heterogeneity (I2  = 77%, P = 0.002). After stratifying by region, high NSP coverage in Europe was associated with a 56% reduction in HCV acquisition risk (RR = 0.44, 95% CI = 0.24-0.80) with low heterogeneity (I2  = 12.3%, P = 0.337), but not in North America (RR = 1.58, I2  = 89.5%, P = < 0.001). Combined OST/NSP is associated with a 74% reduction in HCV acquisition risk (RR = 0.26, 95% CI = 0.07-0.89, I2  = 80% P = 0.007). According to Grades of Recommendation Assessment, Development and Evaluation (GRADE) criteria, the evidence on OST and combined OST/NSP is low quality, while NSP is very low.

CONCLUSIONS

Opioid substitution therapy reduces risk of hepatitis C acquisition and is strengthened in combination with needle and syringe programmes (NSP). There is weaker evidence for the impact of needle syringe programmes alone, although stronger evidence that high coverage is associated with reduced risk in Europe.

Longitudinal injecting risk behaviours among people with a history of injecting drug use in an Australian prison setting: The HITS-p study

BACKGROUND

HCV transmission remains high in prisons globally. Understanding injecting risk behaviours in prisons is crucial to effectively develop and implement HCV prevention programs in this setting including treatment as prevention.

METHODS

HITS-p is a cohort study which enrolled people with a history of injecting drug use in prisons in NSW, Australia from 2005 to 2013. Participants completed an interview at enrolment and follow-up visits to determine injecting behaviours. Generalized estimating equation (GEE) and logistic regression methods were used to assess injecting risk behaviours prior to and following prison entry and to investigate injecting risk behaviours in prison.

RESULTS

Overall, 499 participants with a history of injecting drug use were included (median age, 26 years; 65% male). Participants were significantly less likely to inject drugs following incarceration. Among injectors, participants were less likely to inject ≥weekly but more likely to share a needle/syringe. At enrolment, the proportion reporting any injecting, ≥weekly injecting, and needle/syringe sharing in prison was highest among younger individuals. Younger age was associated with both re-initiation and continuation of injecting drug use following prison entry. Among those continuously imprisoned, younger age was associated with increased odds of any injecting, ≥weekly injecting, and sharing a needle/syringe.

CONCLUSIONS

Upon entry to prison, injecting drug use decreased but syringe sharing increased among injectors. Younger individuals are most likely to exhibit high-risk injecting behaviours in prison. These data highlight the need for improved HCV prevention strategies (including improved needle/syringe access and scale up of HCV therapy) for those at increased risk of HCV transmission in prison, including younger individuals.

Drug use and phylogenetic clustering of hepatitis C virus infection among people who use drugs in Vancouver, Canada: A latent class analysis approach

This study estimated latent classes (ie, unobserved subgroups in a population) of people who use drugs in Vancouver, Canada, and examined how these classes relate to phylogenetic clustering of hepatitis C virus (HCV) infection. HCV antibody-positive people who use drugs from two cohorts in Vancouver, Canada (1996-2012), with a Core-E2 sequence were included. Time-stamped phylogenetic trees were inferred, and phylogenetic clustering was determined by time to most common recent ancestor. Latent classes were estimated, and the association with the phylogenetic clustering outcome was assessed using an inclusive classify/analyse approach. Among 699 HCV RNA-positive participants (26% female, 24% HIV+), recent drug use included injecting cocaine (80%), injecting heroin (70%), injecting cocaine/heroin (ie, speedball, 38%) and crack cocaine smoking (28%). Latent class analysis identified four distinct subgroups of drug use typologies: (i) cocaine injecting, (ii) opioid and cocaine injecting, (iii) crack cocaine smoking and (iv) heroin injecting and currently receiving opioid substitution therapy. After adjusting for age and HIV infection, compared to the group defined by heroin injecting and currently receiving opioid substitution therapy, the odds of phylogenetic cluster membership was greater in the cocaine injecting group (adjusted OR [aOR]: 3.06; 95% CI: 1.73, 5.42) and lower in the crack cocaine smoking group (aOR: 0.06; 95% CI: 0.01, 0.48). Combining latent class and phylogenetic clustering analyses provides novel insights into the complex dynamics of HCV transmission. Incorporating differing risk profiles associated with drug use may provide opportunities to further optimize and target HCV treatment and prevention strategies.

Scaling-up HCV prevention and treatment interventions in rural United States-model projections for tackling an increasing epidemic

BACKGROUND AND AIMS

Effective strategies are needed to address dramatic increases in hepatitis C virus (HCV) infection among people who inject drugs (PWID) in rural settings of the United States. We determined the required scale-up of HCV treatment with or without scale-up of HCV prevention interventions to achieve a 90% reduction in HCV chronic prevalence or incidence by 2025 and 2030 in a rural US setting.

DESIGN

An ordinary differential equation model of HCV transmission calibrated to HCV epidemiological data obtained primarily from an HIV outbreak investigation in Indiana.

SETTING

Scott County, Indiana (population 24 181), USA, a rural setting with negligible baseline interventions, increasing HCV epidemic since 2010, and 55.3% chronic HCV prevalence among PWID in 2015.

PARTICIPANTS

PWID.

MEASUREMENTS

Required annual HCV treatments per 1000 PWID (and initial annual percentage of infections treated) to achieve a 90% reduction in HCV chronic prevalence or incidence by 2025/30, either with or without scaling-up syringe service programmes (SSPs) and medication-assisted treatment (MAT) to 50% coverage. Sensitivity analyses considered whether this impact could be achieved without re-treatment of re-infections, and whether greater intervention scale-up was required due to the increasing epidemic in this setting.

FINDINGS

To achieve a 90% reduction in incidence and prevalence by 2030, without MAT and SSP scale-up, 159 per 1000 PWID (initially 24.9% of infected PWID) need to be HCV-treated annually. However, with MAT and SSP scaled-up, treatment rates are halved (89 per 1000 annually or 14.5%). To reach the same target by 2025 with MAT and SSP scaled-up, 121 per 1000 PWID (19.9%) need treatment annually. These treatment requirements are threefold higher than if the epidemic was stable, and the impact targets are unattainable without retreatment.

CONCLUSIONS

Combined scale-up of hepatitis C virus treatment and prevention interventions is needed to decrease the increasing burden of hepatitis C virus incidence and prevalence in rural Indiana, USA, by 90% by 2025/30.

'Sussing that doctor out.' Experiences and perspectives of people affected by hepatitis C regarding engagement with private general practitioners in South Australia: a qualitative study

BACKGROUND

Australians with chronic hepatitis C (HCV) can access affordable Direct Acting Antiviral (DAA) treatments with high cure rates (>90%), via General Practitioners (GPs). Benefits from this treatment will be maximised if people with HCV readily disclose and engage with private GPs regarding HCV-related issues. Investigating the perceptions and experiences of people affected by HCV with GPs can allow for this pathway to care for HCV to be improved.

METHODS

In 2013-2014, 22 purposively sampled participants from South Australia (SA) were interviewed. They a) had contracted or were at risk of hepatitis C (n = 10), b) were key workers who had clients affected by HCV (n = 6), and c) met both a) and b) criteria (n = 6). The semi-structured interviews were recorded, transcribed and thematically analysed.

RESULTS

People affected by HCV viewed GPs as a source of general healthcare but, due to negative experiences and perceptions, many developed a strategy of "sussing" out doctors before engaging with and disclosing to a GP regarding HCV-related issues. Participants were doubtful about the benefits of engagement and disclosure, and did not assume that they would be provided best-practice care in a non-discriminatory, non-judgemental way. They perceived risks to confidentiality and risks of changes to the care they received from GPs upon disclosure.

CONCLUSION

GPs may need to act in ways that counteract the perceived risks and persuade people affected by HCV of the benefits of seeking HCV-related care.

Direct-acting antiviral agents for HCV infection affecting people who inject drugs

Globally, 12 million people are estimated to have injected drugs in the past year, 50% of whom have chronic HCV infection, with people who have previously injected drugs presenting an additional large reservoir of infection. The availability of simple and tolerable interferon-free direct-acting antiviral agents (DAAs) for HCV infection, which have a cure rate of >95% represents one of the most exciting advances in clinical medicine in the past few decades. Adherence and response to DAA therapy among people who inject drugs (PWID) receiving opioid substitution therapy (OST) in clinical trials are comparable to populations without a history of injecting drugs. Further data are required among current PWID not receiving OST. Given the potential prevention benefits of treatment, DAAs have enhanced cost-effectiveness among PWID. As HCV therapy is expanded to populations of PWID with high-risk behaviours for re-exposure, acknowledgement that HCV reinfection will occur is crucial, and appropriate strategies must be in place to maximize prevention of reinfection and offer retreatment for reinfection. This Review will also discuss essential components for broadening access to HCV care for PWID as we strive for the global elimination of HCV infection.

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.