Evaluating the population impact of hepatitis C direct acting antiviral treatment as prevention for people who inject drugs (EPIToPe) - a natural experiment (protocol)

Evaluating the effect of direct-acting antiviral agent treatment scale-up on Hepatitis C virus prevalence among people who inject drugs in UK

BACKGROUND

There is limited empirical work assessing the effectiveness of treatment as prevention (TasP) in reducing HCV prevalence among people who inject drugs (PWID). Here, we used survey data from the UK during 2010-2020, to evaluate the impact of direct-acting antiviral agent (DAA) treatment scale-up, which started in 2015, on HCV prevalence among PWID.

METHODS

We fitted a logistic regression to time/location specific data on prevalence from the Needle Exchange Surveillance Initiative in Scotland and Unlinked Anonymous Monitoring programme in England. For each post-intervention year and location, we quantified the effect of TasP as the difference between estimated prevalence and its counterfactual (prevalence in the absence of scale-up). Progress to elimination was assessed by comparing most recent prevalence against one in 2015.

RESULTS

In 2015, prevalence ranged from 0.44 to 0.71 across the 23 locations (3 Scottish, 20 English). Compared to counterfactuals, there was an absolute reduction of 46% (95% credible interval [32%,59%]) in Tayside in 2020, 35% ([24%,44%]) in Glasgow in 2019, and 25% ([10%,39%]) in the Rest of Scotland in 2020. The English sites with highest estimated absolute reductions in 2021 were South Yorkshire (45%, [29%,58%]), Thames Valley (49%, [34%,59%]) and West London (41%, [14%,59%]). Compared to 2015, there was 80% probability that prevalence had fallen by 65% in Tayside, 53% in Glasgow and 36% in the Rest of Scotland. The English sites with highest % prevalence decrease compared to 2015, achieved with probability 80%, were Chesire & Merseyside (70%), South Yorkshire (65%) and Thames Valley (71%). Higher treatment intensity was associated with higher reductions in prevalence.

CONCLUSION

Conclusion. Real-world evidence showing substantial reductions in chronic HCV associated with increase of HCV treatment scale-up in the community thus supporting the effectiveness of HCV treatmen as prevention in people who inject drugs.

In search of a 'good number': knowledge controversy and population estimates in the endgame of hepatitis C elimination

We explore the contentious life of a metric used to assess a country's progress in relation to global disease elimination targets. Our topic is hepatitis C elimination, and our context is Australia. A fundamental metric in the calculation of progress toward hepatitis C elimination targets, as set by the WHO, is the population prevalence of people living with hepatitis C. In Australia, this modelled estimate has generated some controversy, largely through its repeated downsizing as an effect of calculus. The 2015 baseline population estimate in Australia, from which measures of current elimination progress are assessed, has reduced, over time, by around 30%. Informed by a social study of science approach, we used qualitative interviews with 32 experts to explore the knowledge controversy. The controversy is narrated through the core concerns of 'scale' and 'care', with narratives aligning differently to imaginaries of 'science' and 'community'. We trace how constitutions of 'estimate' and 'number' circulate in relation to 'population' and 'people', and as affective values. We show how enactments of estimates and numbers materialise hepatitis elimination in different ways, with policy implications. The event of the knowledge controversy opens up the social and political life of enumerations-for science and community-inviting deliberation on how to make 'good numbers' in the race to eliminate hepatitis C.

A multicomponent holistic care pathway for people who use drugs in Tayside, Scotland

BACKGROUND

People Who Use Drugs (PWUD) are at high risk of non-fatal overdose and other drug-related harms. The United Kingdom drugs policy landscape makes it challenging to support those at risk. Tayside, in East Scotland, has a sizeable population at risk of drug-related harms. In 2021, the National Health Service implemented a care pathway for PWUD to provide multidimensional healthcare interventions. We aimed to quantify drug-related harms; assess wider health and well-being; and understand substance use trends and behaviours, among those engaged in the pathway.

METHODS

Existing community-embedded blood-borne virus pathways were adapted to provide multiple healthcare assessments over three visits. We undertook an observational cohort study to analyse uptake and outcomes for the initial cohort of PWUD engaged at appointment one.

RESULTS

From August 2021-September 2022, 150 PWUD engaged with the pathway. Median age was 39 (34-42) years, 108 (72%) were male, and 124 (83%) lived in deprived areas. Seventy (47%) had been disengaged from healthcare for over a year. Polysubstance use was reported by 124 (83%), 42 (28%) disclosed injecting daily, and 54 (36%) shared equipment. Fifty-four (36%) experienced recent non-fatal overdose, and there were six overdose fatalities (4.1 [1.5-9.0] per 100PY). The offer of take-home naloxone was accepted by 108 (72%). Fourteen (9%) were diagnosed with Hepatitis C and two (1%) with HIV. Renal, hepatological, and endocrine impairment were observed among 30 (20%), 23 (15%), and 11 (7%), people respectively. Ninety-six (65%) had high risk of clinical depression. Forty-eight (32%) declined Covid-19 vaccination.

CONCLUSION

The pathway engaged PWUD with high exposure to recent non-fatal overdose and other drug-related harms, alongside co-morbid health issues. Our results suggest multi-dimensional health assessments coupled with harm reduction in community settings, with appropriate linkage to care, are warranted for PWUD. Service commissioners should seek to integrate these assessments where possible.

Nationwide Hepatitis C Serosurvey and Progress Towards Hepatitis C Virus Elimination in the Country of Georgia, 2021

BACKGROUND

The country of Georgia initiated its hepatitis C virus (HCV) elimination program in 2015, at which point a serosurvey showed the adult prevalence of HCV antibody (anti-HCV) and HCV RNA to be 7.7% and 5.4%, respectively. This analysis reports hepatitis C results of a follow-up serosurvey conducted in 2021, and progress towards elimination.

METHODS

The serosurvey used a stratified, multistage cluster design with systematic sampling to include adults and children (aged 5-17 years) providing consent (or assent with parental consent). Blood samples were tested for anti-HCV and if positive, HCV RNA. Weighted proportions and 95% confidence intervals (CI) were compared with 2015 age-adjusted estimates.

RESULTS

Overall, 7237 adults and 1473 children were surveyed. Among adults, the prevalence of anti-HCV was 6.8% (95% CI, 5.9-7.7). The HCV RNA prevalence was 1.8% (95% CI, 1.3-2.4), representing a 67% reduction since 2015. HCV RNA prevalence decreased among those reporting risk factors of ever injecting drugs (51.1% to 17.8%), and ever receiving a blood transfusion (13.1% to 3.8%; both P < .001). No children tested positive for anti-HCV or HCV RNA.

CONCLUSIONS

These results demonstrate substantial progress made in Georgia since 2015. These findings can inform strategies to meet HCV elimination targets.

The Role of Nonprofit and Nongovernmental Organizations and People With Viral Hepatitis on the Path Toward Hepatitis C Virus Elimination

Nonprofit and nongovernmental organizations have driven and continue to drive hepatitis C elimination by putting people with viral hepatitis and their affected communities at the center of hepatitis elimination efforts. They have been key in driving the decentralization of services and community-based delivery in the hepatitis care pathway to improve the health and well-being of the populations most affected by hepatitis C. This article explores how the formation of the World Hepatitis Alliance (WHA), an international network of community organizations in >100 countries, led to powerful advocacy from community leaders and people with hepatitis, resulting in the establishment of World Hepatitis Day. Since then, the World Health Organization (WHO) has recognized the importance of viral hepatitis by setting the 2030 global elimination targets. WHA and WHO have collaborated on 3 World Hepatitis Summits, which have built momentum across many sectors to help elevate hepatitis through the global health agenda. The article discusses their paradigm-shifting campaigns and also presents civil society organizations' hepatitis elimination efforts in Egypt, Mongolia, Bangladesh, and the United Kingdom and their significant impact through local resource mobilization and engagement of national governments.

Improved health-related quality of life after hepatitis C viraemic clearance among people who inject drugs may not be durable

BACKGROUND AND AIMS

Chronic infection with the hepatitis C virus (HCV) has a detrimental impact on health-related quality of life (QoL). Scale-up of HCV direct-acting antiviral (DAA) therapy among people who inject drugs (PWID) is underway in several countries since the introduction of interferon-free regimens. This study aimed to assess the impact of DAA treatment success on QoL for PWID.

DESIGN

Cross-sectional study using two rounds of the Needle Exchange Surveillance Initiative, a national anonymous bio-behavioural survey and a longitudinal study involving PWID who underwent DAA therapy.

SETTING

The setting for the cross-sectional study was Scotland (2017-2018, 2019-2020). The setting for the longitudinal study was the Tayside region of Scotland (2019-2021).

PARTICIPANTS

In the cross-sectional study PWID were recruited from services providing injecting equipment (n = 4009). In the longitudinal study, participants were PWID on DAA therapy (n = 83).

MEASUREMENTS

In the cross-sectional study, the association between QoL (measured using the EQ-5D-5L quality of life instrument) and HCV diagnosis and treatment was assessed using multilevel linear regression. In the longitudinal study, QoL was compared at four timepoints using multilevel regression, from treatment commencement until 12 months following commencement.

FINDINGS

In the cross-sectional study, 41% (n = 1618) were ever chronically HCV infected, of whom 78% (n = 1262) were aware of their status and of whom 64% (n = 704) had undergone DAA therapy. There was no evidence for a marked QoL improvement associated with viral clearance among those treated for HCV (B = 0.03; 95% CI, -0.03 to 0.09). In the longitudinal study, improved QoL was observed at the sustained virologic response test timepoint (B = 0.18; 95% CI, 0.10-0.27), but this was not maintained at 12 months following start of treatment (B = 0.02; 95% CI, -0.05 to 0.10).

CONCLUSIONS

Successful direct-acting antiviral therapy for hepatitis C infection may not lead to a durable improvement in quality of life among people who inject drugs, although there may be a transient improvement around the time of sustained virologic response. Economic models of the impact of scaling-up treatment may need to include more conservative quality of life benefits over and above reductions in mortality, disease progression and transmission of infection.

Securing wider EU commitment to the elimination of hepatitis C virus

In 2016, the Hepatitis B and C Public Policy Association (HepBCPPA), gathered all the main stakeholders in the field of hepatitis C virus (HCV) to launch the now landmark HCV Elimination Manifesto, calling for the elimination of HCV in the EU by 2030. Since then, many European countries have made progress towards HCV elimination. Multiple programmes-from the municipality level to the EU level-were launched, resulting in an overall decrease in viremic HCV infections and liver-related mortality. However, as of 2021, most countries are not on track to reach the 2030 HCV elimination targets set by the WHO. Moreover, the COVID-19 pandemic has resulted in a decrease in HCV diagnoses and fewer direct-acting antiviral treatment initiations in 2020. Diagnostic and therapeutic tools to easily diagnose and treat chronic HCV infection are now well established. Treating all patients with chronic HCV infection is more cost-saving than treating and caring for patients with liver-related complications, decompensated cirrhosis or hepatocellular carcinoma. It is more important than ever to reinforce and scale-up action towards HCV elimination. Yet, efforts urgently need the dedicated commitment of policymakers at all governmental and policy levels. Therefore, the third EU Policy Summit, held in March 2021, featured EU parliamentarians and other key decision makers to promote dialogue and take strides towards securing wider EU commitment to advance and achieve HCV elimination by 2030. We have summarized the key action points and reported the 'Call-to-Action' statement supported by all the major relevant European associations in the field.

Laying the foundations for hepatitis C elimination: evaluating the development and contribution of community care pathways to diagnostic efforts

BACKGROUND

Hepatitis C Virus (HCV) is a public health threat which contributes substantially to the global burden of liver disease. There is much debate about effective approaches to scaling up diagnosis of HCV among risk groups. Tayside, a region in the East of Scotland, developed low-threshold community pathways for HCV to lay the foundations of an elimination strategy. In this retrospective study, we sought to: quantify the contribution of community pathways to increasing HCV diagnosis; understand if shifting diagnosis to community settings led to a higher proportion of individuals tested for HCV being actively infected; and describe functional characteristics of the care pathways.

METHODS

Descriptive statistics were used to for analysis of routinely-collected HCV testing data from 1999 to 2017, and a review of the development of the care pathways was undertaken. Community-based testing was offered through general practices (GP); nurse outreach clinics; prisons; drug treatment services; needle and syringe provision (NSP) sites; community pharmacies; and mosques.

RESULTS

Anti-HCV screening was undertaken on 109,430 samples, of which 5176 (4.7%) were reactive. Of all samples, 77,885 (71.2%) were taken in secondary care; 25,044 (22.9%) in GPs; 2970 (2.7%) in prisons; 2415 (2.2%) in drug services; 753 (0.7%) in NSPs; 193 (0.2%) pharmacies; and 170 (0.1%) in mosques. The highest prevalence of HCV infection among those tested was in NSP sites (26%), prisons (14%), and drug treatment centres (12%).

CONCLUSIONS

Decentralised care pathways, particularly in harm reduction and other drug service settings, were key to increasing diagnosis of HCV in the region, but primary and secondary care remain central to elimination efforts.

Falling treatment uptake in the hepatitis C care cascade is a growing threat to achieving elimination

Most high-income countries are not on track to achieve the World Health Organization hepatitis C elimination targets. As elimination programmes assess growing proportions of patients in community-based pathways, rates of treatment uptake may fall. We aimed to identify factors associated with DAA treatment uptake and measure changes in their prevalence over time. We performed a time-to-treatment analysis on 2728 patients approved for hepatitis C Direct-Acting Antiviral treatment in the North Central London region between January 2016 and October 2019. We investigated the association between treatment uptake and factors including assessment/treatment setting (hospital, drug service or prison), patient age, gender, injection drug use, harmful alcohol use, cirrhosis status and previous treatment. The likelihood of treatment uptake was reduced by three independent risk factors. These included assessment setting: prison-based or drug-service pathways (aHR 0.29 or 0.81 vs. hospital outpatient pathway, 95% CI 0.21-0.40 and 0.70-0.94 respectively, p < .001); being UK-born (aHR 0.89 vs. non-UK born, 0.82-0.98, p = .01); and history of harmful alcohol use (aHR 0.84 vs. no history, 0.72-0.99, p = .04). The average number of these risk factors for not starting treatment per patient increased over time (R2  = 0.66 p < .001). Independent of these, there was an additional 5% reduction in rate of treatment initiation in each successive year of the programme (aHR 0.95, 0.91-0.99, p = .02). In conclusion, disengagement from care before treatment uptake was found to be a growing threat to elimination. Despite provision of community-based test-to-cure pathways, there are persistent barriers to treatment uptake and these are increasing over time.

Randomized clinical trial: Direct-acting antivirals as treatment for hepatitis C in people who inject drugs: Delivered in needle and syringe programs via directly observed therapy versus fortnightly collection

Hepatitis C virus (HCV) treatment in people who inject drugs (PWID) is delivered within settings frequented by PWID, such as needle and syringe programs (NSP). The optimal direct-acting antiviral (DAA) dispensing regimen among NSP clients is unknown. This study compared cures (Sustained virologic response 12 weeks post-treatment, [SVR₁₂ ]) across three dispensing schedules to establish non-inferiority of fortnightly dispensing versus directly observed therapy. The ADVANCE HCV study was a randomized, unblinded trial, recruiting PWID attending NSP in Tayside, Scotland, between January 2018 and November 2019. HCV-positive participants were randomized to receive DAAs via directly observed therapy, fortnightly provision or fortnightly provision with psychological intervention. A modified intention to treat analysis was used to identify differences in cures between the three treatment regimes. The study was registered with clinicaltrials.gov; NCT03236506. A total of 110 participants completed the study. 33 participants received directly observed therapy, with 90.91% SVR₁₂ ; 37 received fortnightly provision, with 86.49% SVR₁₂ and 40 received fortnightly provision and psychological intervention at treatment initiation, with 92.50% SVR₁₂ . Analysis showed no significant difference in SVR₁₂ (p = 0.67). This study did not demonstrate a statistically significant difference in cure rate between groups. This provides evidence of the non-inferiority of fortnightly dispensing of direct-acting antivirals (DAAs) compared to directly observed therapy among PWID. It suggests that tight control of adherence through directly observed therapy dispensing of DAAs among this population offers no therapeutic advantage. Therefore, less restrictive dispensing patterns can be used, tailored to patient convenience.

Reaching people receiving opioid agonist therapy at community pharmacies with hepatitis C virus: an international randomised controlled trial

BACKGROUND

Conventional healthcare models struggle to engage those at risk of hepatitis C virus (HCV) infection. This international study evaluated point-of-care (PoC) HCV RNA diagnostic outreach and direct-acting antiviral (DAA) treatment for individuals receiving opioid agonist therapy (OAT) in community pharmacies.

AIMS

We assessed the effectiveness of a roving nurse-led pathway offering PoC HCV RNA testing to OAT clients in community pharmacies relative to conventional care.

METHODS

Pharmacies in Scotland, Wales, and Australia were randomised to provide PoC HCV RNA testing or conventional referral. Pharmacists directed OAT clients to on-site nurses (intervention) or local clinics (control). Infected participants were treated with DAAs, alongside OAT. Primary outcome was the number of participants with sustained virologic response at 12 weeks (SVR) and analysed using mixed effects logistic regression in the intention-to-treat (ITT) population.

RESULTS

Forty pharmacies were randomised. The ITT population contained 1410 OAT clients. In the conventional arm (n = 648), 62 (10%) agreed to testing, 17 (27%) were tested, 6 (35%) were positive and 5 (83%) initiated treatment. In the intervention arm (n = 762), 148 (19%) agreed to testing, 144 (97%) were tested, 23 (16%) were positive and 22 (96%) initiated treatment. SVR was obtained by 2 (40%; conventional) and 18 (82%; intervention). Intervention arm participants had higher odds of testing, OR 16.95 (7.07-40.64, p < 0.001); treatment, OR 4.29 (1.43-12.92, p = 0.010); and SVR, OR 8.64 (1.82-40.91, p = 0.007).

CONCLUSIONS

Nurse-led PoC diagnosis in pharmacies made HCV care more accessible for OAT clients relative to conventional care. However, strategies to improve testing uptake are required.

TRIAL REGISTRATION

NCT03935906.

Methods and indicators to validate country reductions in incidence of hepatitis C virus infection to elimination levels set by WHO

One of the main goals of the 2016 Global Health Sector Strategy on viral hepatitis is the elimination of hepatitis C virus (HCV) as a public health problem by 2030, defined as an 80% reduction in incidence and 65% reduction in mortality relative to 2015. Although monitoring HCV incidence is key to validating HCV elimination, use of the gold-standard method, which involves prospective HCV retesting of people at risk, can be prohibitively resource-intensive. Additionally, few countries collected quality data in 2015 to enable an 80% decrease by 2030 to be calculated. Here, we first review different methods of monitoring HCV incidence and discuss their resource implications and applicability to various populations. Second, using mathematical models developed for various global settings, we assess whether trends in HCV chronic prevalence or HCV antibody prevalence or scale-up levels for HCV testing, treatment, and preventative interventions can be used as reliable alternative indicators to validate the HCV incidence target. Third, we discuss the advantages and disadvantages of an absolute HCV incidence target and suggest a suitable threshold. Finally, we propose three options that countries can use to validate the HCV incidence target, depending on the available surveillance infrastructure.

Developing a primary care-initiated hepatitis C treatment pathway in Scotland: a qualitative study

BACKGROUND

The ease of contemporary hepatitis C virus (HCV) therapy has prompted a global drive towards simplified and decentralised treatment pathways. In some countries, primary care has become an integral component of community-based HCV treatment provision. In the UK, however, the role of primary care providers remains largely focused on testing and diagnosis alone.

AIM

To develop a primary care-initiated HCV treatment pathway for people who use drugs, and recommend theory-informed interventions to help embed that pathway into practice.

DESIGN AND SETTING

A qualitative study informed by behaviour change theory. Semi-structured interviews were undertaken with key stakeholders (n = 38) primarily from two large conurbations in Scotland.

METHOD

Analysis was three-stage. First, a broad pathway structure was outlined and then sequential pathway steps were specified; second, thematic data were aligned to pathway steps, and significant barriers and enablers were identified; and, third, the Theoretical Domains Framework and Behaviour Change Wheel were employed to systematically develop ideas to enhance pathway implementation, which stakeholders then appraised.

RESULTS

The proposed pathway structure spans broad, overarching challenges to primary care-initiated HCV treatment. The theory-informed recommendations align with influences on different behaviours at key pathway steps, and focus on relationship building, routinisation, education, combating stigmas, publicising the pathway, and treatment protocol development.

CONCLUSION

This study provides the first practicable pathway for primary care-initiated HCV treatment in Scotland, and provides recommendations for wider implementation in the UK. It positions primary care providers as an integral part of community-based HCV treatment, providing workable solutions to ingrained barriers to care.

Population-level estimates of hepatitis C reinfection post scale-up of direct-acting antivirals among people who inject drugs

BACKGROUND & AIMS

Scale-up of highly effective direct-acting antivirals (DAAs) for HCV among people who inject drugs (PWID) in Scotland has led to a reduction in the prevalence of viraemia in this population. However, the extent of reinfection among those treated with DAAs remains uncertain. We estimated HCV reinfection rates among PWID in Scotland by treatment setting, pre- and post-introduction of DAAs, and the potential number of undiagnosed reinfections resulting from incomplete follow-up testing.

METHODS

Through linkage of national clinical and laboratory HCV data, a retrospective cohort of PWID who commenced treatment between 2000-2018 and achieved a sustained virological response (SVR) were followed up for reinfection to December 2019. Reinfection was defined as a positive HCV antigen or RNA test.

RESULTS

Of 5,686 SVRs among 5,592 PWID, 4,126 (73%) had an HCV RNA or antigen test post-SVR. Of those retested, we identified 361 reinfections (3.9/100 person-years [PY]). The reinfection rate increased from 1.5/100 PY among PWID treated in 2000-2009 to 8.8/100 PY in 2017-2018. The highest reinfection rates were observed among those treated in prison (14.3/100 PY) and community settings (9.5/100 PY). Among those treated in the DAA era (2015-2018), 68% were tested within the first year post-SVR but only 30% in the second year; while 169 reinfections were diagnosed in follow-up, an estimated 200 reinfections (54% of the estimated total) had gone undetected.

CONCLUSIONS

HCV reinfection rates among PWID in Scotland have risen alongside the scale-up of DAAs and broadened access to treatment for those at highest risk, through delivery in community drug services. Promotion of HCV testing post-SVR among PWID is essential to ensure those reinfected are identified and retreated promptly.

LAY SUMMARY

Increased rates of hepatitis C reinfection in Scotland were observed following the rapid scale-up of highly effective direct-acting antiviral (DAA) treatments among people who inject drugs. This demonstrates that community-based treatment pathways are reaching high-risk groups, regarded vital in efforts to eliminate the virus. However, we estimate that less than half of reinfections have been detected in the DAA era because of inadequate levels of retesting beyond the first year following successful treatment. Sustained efforts that involve high coverage of harm reduction measures and high uptake of annual testing are required to ensure prompt diagnosis and treatment of those reinfected if the goals of elimination are to be met.

Real-world outcomes of rapid regional hepatitis C virus treatment scale-up among people who inject drugs in Tayside, Scotland

BACKGROUND

In 2017, Tayside, a region in the East of Scotland, rapidly scaled-up Hepatitis C Virus (HCV) outreach and treatment among People Who Inject Drugs (PWID) using novel community care pathways.

AIMS

We aimed to determine treatment outcomes for PWID during the scale-up against pre-determined targets; and assess re-infection, mortality, and post-treatment follow up.

METHODS

HCV treatment was delivered in community pharmacies, drug treatment centres, nurse-led outreach clinics, prisons, and needle exchanges, alongside conventional hospital care. We retrospectively analysed clinical outcomes and compared pathways using logistic regression models.

RESULTS

Of 800 estimated HCV-infected PWID, 718 (90%) were diagnosed. 713 treatments commenced among 662 (92%) PWID, delivering 577 (81%) Sustained Virologic Responses (SVR). SVR was 91% among those who attended for testing. Forty-six individuals were treated more than once. Needle exchanges and community pharmacies initiated 49% of all treatments. Regression analyses implied pharmacies had superior follow-up, but there was no difference in likelihood of achieving SVR in community pathways relative to hospital care. Re-infection occurred 39 times over 256.57 person years (PY), yielding a rate of 15.20 per 100 PY (95% CI 10.81-20.78). 54 deaths occurred (29 drug related) over 1,553.04 PY, yielding a mortality rate of 3.48 per 100 PY (95% CI 2.61-4.54). Drug-related mortality was 1.87 per 100 PY (95% CI 1.25-2.68).

CONCLUSIONS

Rapid HCV treatment scale-up to PWID in community settings, whilst maintaining high SVR, is achievable. However, other interventions are required to minimise re-infection; reduce drug-related deaths; and improve post-SVR follow-up testing regionally.

Hepatitis C reinfection by treatment pathway among people who inject drugs in Tayside, Scotland

The efficacy of direct-acting antivirals (DAA) provides an excellent opportunity to scale up HCV diagnosis and treatment, achieving the WHO target of HCV elimination by 2030. However, HCV reinfection among people who inject drugs (PWID) remains a concern and may impede elimination efforts. We assessed reinfection rates among PWID across six specialized treatment pathways, following DAA-based and interferon-based therapies in Tayside, Scotland. Data were collected retrospectively for every treatment episode that resulted in a sustained viral response (SVR) after undergoing treatment. Reinfection rates were calculated for each treatment pathway: hospital outpatient clinic; community pharmacy; drug treatment outreach; prison clinic; nurse-led outreach clinic; and injection equipment provision site. Reinfection is defined as a positive RNA test result after SVR. Incidences of reinfection are expressed in 100 person-years (PYs). In total, 916 treatment episodes met selection criteria. Of these, 100 reinfections were identified, generating an overall reinfection rate of 5.27 per 100 PYs (95%CI: 4.36-6.38). The hospital outpatient clinic had the lowest reinfection incidence (1.81 per 100 PYs, 95%CI: 1.11-2.93), with the injection equipment provision site treatment pathway having the highest reinfection incidence (19.89 per 100 PYs, 95%CI: 14.91-26.54). The incidence of reinfection among those treated with interferon-based therapies and those treated with DAA-based therapies was 4.93 per 100 PYs (95%CI: 3.97-6.11) and 7.17 per 100 PYs (95%CI: 4.75-10.82), respectively. Specialized treatment pathways in Tayside yield varying reinfection incidence rates, with different subpopulations of patients at varying risk of reinfection post-SVR. Results suggest that resources should be targeted at the injection equipment provision site pathway in order to reduce the incidence of reinfection and achieve elimination targets. The study found comparable rates of reinfection following interferon-based and DAA-based therapies, providing support for widening access to treatment services.

The impact of direct-acting antivirals on hepatitis C viraemia among people who inject drugs in England; real-world data 2011-2018

Direct-acting antiviral (DAA) therapy for anybody with viraemic HCV infection has been scaled-up in England since 2017. To assess early impacts, we investigated trends in, and factors associated with, HCV viraemia among people who inject drugs (PWID). We also examined trends in self-reported treatment access. Bio-behavioural data from an annual, national surveillance survey of PWID (2011-2018) estimated trends in viraemic prevalence among HCV antibody-positive PWID. Multivariable logistic regression identified characteristics independently associated with viraemia. Trends in treatment access were examined for PWID with known infection. Between 2011 and 2016, viraemic prevalence among antibody-positive PWID remained stable (2011, 57.7%; 2016, 55.8%) but decreased in 2017 (49.4%) and 2018 (50.4%) (both p < 0.001). After adjustment for demographic and behavioural characteristics, there remained significant reduction in viraemia in 2017 (adjusted odds ratio [aOR] 0.79, 95% CI 0.65-0.94) and 2018 (aOR 0.79, 95% CI 0.66-0.93) compared to 2016. Other factors associated with viraemia were male gender (aOR 1.68, 95% CI 1.53-1.86), geographical region, injecting in past year (aOR 1.26, 95% CI 1.13-1.41), imprisonment (aOR 1.14, 95% CI 1.04-1.31) and homelessness (aOR 1.17, 95% CI 1.04-1.31). Among non-viraemic PWID with known infection, the proportion reporting ever receiving treatment increased in 2017 (28.7%, p < 0.001) and 2018 (38.9%, p < 0.001) compared to 2016 (14.5%). In conclusion, there has been a small reduction in HCV viraemia among antibody-positive PWID in England since 2016, alongside DAA scale-up, and some indication that treatment access has improved in the same period. Population-level monitoring and focus on harm reduction is critical for achieving and evaluating elimination.

Reduction in the population prevalence of hepatitis C virus viraemia among people who inject drugs associated with scale-up of direct-acting anti-viral therapy in community drug services: real-world data

BACKGROUND AND AIMS

There has been little empirical evidence to show the 'real-world' impact of scaling-up direct-acting anti-viral (DAA) treatment among people who inject drugs (PWID) on hepatitis C virus (HCV) viraemia at a population level. We aimed to assess the population impact of rapid DAA scale-up to PWID delivered through community services-including drug treatment, pharmacies, needle exchanges and prisons-in the Tayside region of Scotland, compared with Greater Glasgow and Clyde (GGC) and the Rest of Scotland (RoS).

DESIGN, SETTING AND PARTICIPANTS

Natural experiment, evaluated using data from national biennial surveys of PWID and national clinical data. Services providing injecting equipment (2010-18) and HCV treatment clinics (2017-18) across Scotland. A total of 12 492 PWID who completed a questionnaire and provided a blood spot (tested for HCV-antibodies and RNA); 4105 individuals who initiated HCV treatment.

INTERVENTION AND COMPARATOR, MEASUREMENTS

The intervention was rapid DAA scale-up among PWID, which occurred in Tayside. The comparator was GGC/RoS. Trends in HCV viraemia and uptake of HCV therapy over time; sustained viral response (SVR) rates to therapy by region and treatment setting.

FINDINGS

Uptake of HCV therapy (last year) among PWID between 2013-14 and 2017-18 increased from 15 to 43% in Tayside, 6 to 16% in GGC and 11 to 23% in RoS. Between 2010 and 2017-18, the prevalence of HCV viraemia (among antibody-positives) declined from 73 to 44% in Tayside, 67 to 58% in GGC and 64 to 55% in RoS. The decline in viraemia was greater in Tayside [2017-18 adjusted odds ratio (aOR) = 0.47, 95% confidence interval (CI) = 0.30-0.75, P = 0.001] than elsewhere in Scotland (2017-18 aOR = 0.89, 95% CI = 0.74-1.07, P = 0.220) relative to the baseline of 2013-14 in RoS (including GGC). Per-protocol SVR rates among PWID treated in community sites did not differ from those treated in hospital sites in Tayside (97.4 versus 100.0%, P = 0.099).

CONCLUSIONS

Scale-up of direct-acting anti-viral treatment among people who inject drugs can be achieved through hepatitis C virus (HCV) testing and treatment in community drug services while maintaining high sustained viral response rates and, in the Tayside region of Scotland, has led to a substantial reduction in chronic HCV in the population.

Futures-oriented drugs policy research: Events, trends, and speculating on what might become

One concern in the field of drugs policy is how to make research more futures-oriented. Tracing trends and events with the potential to alter drug futures are seen as ways of becoming more prepared. This challenge is made complex in fast evolving drug markets which entangle with shifting social and material relations at global scale. In this analysis, we argue that drugs policy research orientates to detection and discovery based on the recent past. This narrows future-oriented analyses to the predictable and probable, imagined as extensions of the immediate and local present. We call for a more speculative approach; one which extends beyond the proximal, and one which orientates to possibilities rather than probabilities. Drawing on ideas on speculation from science and technology and futures studies, we argue that speculative research holds potential for more radical alterations in drugs policy. We encourage research approaches which not only valorise knowing in relation to what might happen but which conduct experiments on what could be. Accordingly, we trace how speculative research makes a difference by altering the present through making deliberative interventions on alternative policy options, including policy scenarios which make a radical break with the present. We look specifically at the 'Big Event' and 'Mega Trend' as devices of speculative intervention in futures-oriented drugs policy research. We illustrate how the device of Mega Trend helps to trace as well as to speculate on some of the entangling elements affecting drug futures, including in relation to climate, environment, development, population, drug production, digitalisation, biotechnology, policy and discourse.

Excitable models: Projections, targets, and the making of futures without disease

In efforts to control disease, mathematical models and numerical targets play a key role. We take the elimination of a viral infection as a case for exploring mathematical models as 'evidence-making interventions'. Using interviews with mathematical modellers and implementation scientists, and focusing on the emergence of models of 'treatment-as-prevention' in hepatitis C control, we trace how projections detach from their calculative origins as social and policy practices. Drawing on the work of Michel Callon and others, we show that modelled projections of viral elimination circulate as 'qualculations', taking flight via their affects, including as anticipation. Modelled numerical targets do not need 'actual numbers' or precise measurements to perform their authority as evidence of viral elimination or as situated matters-of-concern. Modellers grapple with the ways that their models transform in policy and social practices, apparently beyond reasonable calculus. We highlight how practices of 'holding-on' to projections in relation to imaginaries of 'evidence-based' science entangle with the 'letting-go' of models beyond calculus. We conclude that the 'virtual precision' of models affords them fluid evidence-making potential. We imagine a different mode of modelling science in health, one more attuned to treating projections as qualculative, affective and relational, as excitable matter.

Rapid point-of-care (POC) testing for Hepatitis C antibodies in a very high prevalence setting: persons injecting drugs in Tallinn, Estonia

BACKGROUND

Between December 2018 and January of 2019, we evaluated the accuracy of the point-of-care Hepatitis C (HCV) antibody test (POC; OraQuick HCV) used at a community-based needle and syringe exchange program serving persons who inject drugs in Tallinn, Estonia.

METHODS

We compared the results of screening for HCV antibodies by OraQuick (oral swab) and enzyme immunoassay (EIA; blood draw) and assessed test results implications in a high prevalence setting. Findings Of the 100 participants, 88 (88%) had reactive POC test results, and 93 were HCV antibody positive on EIA testing. Sensitivity, specificity and negative predictive value (NPV) for the POC assay with EIA as the relevant reference test were as follows: 94.6% (95% CI 90.0-99.2%), 100% and 58.3% (95% CI 30.4-86.2%). Of the 12 testing, HCV-negative with the POC only 7 (58.3%) were true negatives.

CONCLUSIONS

Oral swab rapid testing HCV screening in this nonclinical setting was sensitive and specific but had unacceptably low NPV. In high prevalence settings, POC tests with high sensitivity and that directly measure HCV RNA may be warranted.

Provider-related barriers and enablers to the provision of hepatitis C treatment by general practitioners in Scotland: A behaviour change analysis

The ease of direct-acting antiviral (DAA) medications for hepatitis C virus (HCV) has provided an opportunity to decentralize HCV treatment into community settings. However, the role of non-specialist clinicians in community-based pathways has received scant attention to date. This study examined barriers and enablers to expanding the role of general practitioners (GPs) in HCV treatment provision, using simple behaviour change theory as a conceptual framework. A maximum variation sample of 22 HCV treatment providers, GPs and HCV support workers participated in semi-structured interviews. Data were inductively coded, and the resulting codes deductively mapped into three principal components of behaviour change: capability, opportunity and motivation (COM-B). By this process, a number of provider- and systemic-level barriers and enablers were identified. Key barriers included the pre-treatment assessment of liver fibrosis, GP capacity and the 'speciality' of HCV care. Enablers included the simplicity of the drugs, existing GP/patient relationships and the provision of holistic care. In addition to these specific factors, the data also exposed an overarching provider understanding of 'HCV treatment' as triumvirate in nature, incorporating the assessment of liver fibrosis, the provision of holistic support and the treatment of disease. This understanding imposes a further fundamental barrier to GP-led treatment as each of these three components needs to be individually addressed. To enable sustainable models of HCV treatment provision by GPs, a pragmatic re-examination of the 'HCV treatment triumvirate' is required, and a paradigm shift from the 'refer and treat' status quo.

High hepatitis C treatment uptake among people with recent drug dependence in New South Wales, Australia

BACKGROUND & AIMS

High HCV treatment uptake among people at most risk of transmission is essential to achieve elimination. We aimed to characterise subpopulations of people with HCV based on drug dependence, to estimate direct-acting antiviral (DAA) uptake in an unrestricted treatment era, and to evaluate factors associated with treatment uptake among people with recent drug dependence.

METHODS

HCV notifications in New South Wales, Australia (1995-2017) were linked to opioid agonist therapy (OAT), hospitalisations, incarcerations, HIV notifications, deaths, and prescription databases. Drug dependence was defined as hospitalisation due to injectable drugs or receipt of OAT, with indicators in 2016-2018 considered recent. Records were weighted to account for spontaneous clearance. Logistic regression was used to analyse factors associated with treatment uptake among those with recent drug dependence.

RESULTS

57,467 people were estimated to have chronic HCV throughout the DAA era. Treatment uptake was highest among those with recent (47%), compared to those with distant (38%), and no (33%) drug dependence. Among those with recent drug dependence, treatment was more likely among those with HIV (adjusted odds ratio [aOR] 1.71; 95% CI 1.24-2.36), recent incarceration (aOR 1.10; 95% CI 1.01-1.19), and history of alcohol use disorder (aOR 1.22; 95% CI 1.13-1.31). Treatment was less likely among women (aOR 0.78; 95% CI 0.72-0.84), patients of Indigenous ethnicity (aOR 0.75; 95% CI 0.69-0.81), foreign-born individuals (aOR 0.86; 95% CI 0.78-0.96), those with outer-metropolitan notifications (aOR 0.90; 95% CI 0.82-0.98), HBV coinfection (aOR 0.69; 95% CI 0.59-0.80), and >1 recent hospitalisation (aOR: 0.91; 95% CI 0.84-0.98).

CONCLUSIONS

These data provide evidence of high DAA uptake among people with recent drug dependence, including those who are incarcerated. Enhancing this encouraging initial uptake among high-risk populations will be essential to achieve HCV elimination.

LAY SUMMARY

To facilitate HCV elimination, those at highest risk of infection and transmission are a treatment priority. This study shows the successes of Australia's universal provision of DAA therapy in reducing the barriers to treatment which have historically persisted among people who inject drugs. Despite higher DAA therapy uptake among those with recent drug dependence, gaps remain. Strategies which aim to reduce marginalisation and increase treatment uptake to ensure equitable HCV elimination must be advanced.

Identifying the Hidden Population: Former Intravenous Drug Users Who Are No Longer in Contact with Services. "Ask a Friend"

People who, after a period of drug use, have changed their lifestyle and left substance use behind them are a hidden population within our communities. Lack of contact with drug services may mean that they are not tested for hepatitis C (HCV) infection through service-led initiatives and, therefore, may be exposed to the chronic morbidity and risk of death inherent with a legacy of HCV infection. This study utilized respondent-driven sampling (RDS) in a novel fashion to find those at historical risk of HCV. The social networks of people with a history of drug use were mapped, and individuals not currently in contact with services were invited to come forward for testing by members of their social network. The study used a reference group to inform study methodology and communication methods to reach out to this hidden population. One hundred and nine individuals received dry blood spot tests for HCV, 17.4% were antibody positive. Fifty one individuals met the inclusion criteria for this study. One hundred and twenty three invite-to-test coupons were issued; however, only one wave of recruitment consisting of one participant resulted from this method. Using RDS in historical social networks was not effective in this study and did not reach this hidden population and increase testing for HCV. This study is registered with clinicaltrials.gov (Ref NCT03697135).

Evaluating the power of the causal impact method in observational studies of HCV treatment as prevention

OBJECTIVES

The causal impact method (CIM) was recently introduced for evaluation of binary interventions using observational time-series data. The CIM is appealing for practical use as it can adjust for temporal trends and account for the potential of unobserved confounding. However, the method was initially developed for applications involving large datasets and hence its potential in small epidemiological studies is still unclear. Further, the effects that measurement error can have on the performance of the CIM have not been studied yet. The objective of this work is to investigate both of these open problems.

METHODS

Motivated by an existing dataset of HCV surveillance in the UK, we perform simulation experiments to investigate the effect of several characteristics of the data on the performance of the CIM. Further, we quantify the effects of measurement error on the performance of the CIM and extend the method to deal with this problem.

RESULTS

We identify multiple characteristics of the data that affect the ability of the CIM to detect an intervention effect including the length of time-series, the variability of the outcome and the degree of correlation between the outcome of the treated unit and the outcomes of controls. We show that measurement error can introduce biases in the estimated intervention effects and heavily reduce the power of the CIM. Using an extended CIM, some of these adverse effects can be mitigated.

CONCLUSIONS

The CIM can provide satisfactory power in public health interventions. The method may provide misleading results in the presence of measurement error.

Population impact of direct-acting antiviral treatment on new presentations of hepatitis C-related decompensated cirrhosis: a national record-linkage study

OBJECTIVE

Population-based studies demonstrating the clinical impact of interferon-free direct-acting antiviral (DAA) therapies are lacking. We examined the impact of the introduction of DAAs on HCV-related decompensated cirrhosis (DC) through analysis of population-based data from Scotland.

DESIGN

Through analysis of national surveillance data (involving linkage of HCV diagnosis and clinical databases to hospital and deaths registers), we determined i) the scale-up in the number of patients treated and achieving a sustained viral response (SVR), and ii) the change in the trend of new presentations with HCV-related DC, with the introduction of DAAs.

RESULTS

Approximately 11 000 patients had been treated in Scotland over the 8-year period 2010/11 to 2017/18. The scale-up in the number of patients achieving SVR between the pre-DAA and DAA eras was 2.3-fold overall and 5.9-fold among those with compensated cirrhosis (the group at immediate risk of developing DC). In the pre-DAA era, the annual number of HCV-related DC presentations increased 4.6-fold between 2000 (30) and 2014 (142). In the DAA era, presentations decreased by 51% to 69 in 2018 (and by 67% among those with chronic infection at presentation), representing a significant change in trend (rate ratio 0.88, 95% CI 0.85 to 0.90). With the introduction of DAAs, an estimated 330 DC cases had been averted during 2015-18.

CONCLUSIONS

National scale-up in interferon-free DAA treatment is associated with the rapid downturn in presentations of HCV-related DC at the population-level. Major progress in averting HCV-related DC in the short-term is feasible, and thus other countries should strive to achieve the same.

HepCare Ireland-a service innovation project

Hepatitis C virus (HCV) remains a major cause of morbidity and death worldwide, with prevalence highest among people who inject drugs (PWID), homeless populations and prisoners. The World Health Organization has published targets to be achieved by 2030 as part of its global health sector strategy to eliminate viral hepatitis. Recent innovations in testing and treatment of HCV mean such goals are achievable with effective infrastructure, political will and funding. 'HepCare Europe' was a 3-year, EU-funded project involving four member states. It sought to develop, implement and evaluate interventions to improve HCV outcomes through multiple-level interventions, running between 2016 and 2019. This paper aims to summarize the methods and present the aggregate cascade of care figures for the Irish components of HepCare. 'HepCare Ireland' contained five integrated work packages: HepCheck, HepLink, HepFriend, HepEd and HepCost. Interventions included intensified screening, community-based assessment, linkage to specialist care, peer training and support, multidisciplinary educational resources and cost-effectiveness analysis. A total of 812 participants were recruited across the three clinical work packages in Ireland. Two hundred and fifty-seven (31.7%) of the tested participants had an HCV antibody-positive result, with 162 (63.0%) testing positive for HCV RNA. At the time of writing (6th of November 2019), 57 (54.8%) of participants put on treatment had achieved SVR12, with 44 (42.3%) still undergoing treatment. In HepCheck, HepLink. HepEd and HepFriend, we demonstrate a series of interventions to improve Irish HCV outcomes. Our findings highlight the benefits of multilevel interventions in HCV care.

Clinical effectiveness of pharmacist-led versus conventionally delivered antiviral treatment for hepatitis C virus in patients receiving opioid substitution therapy: a pragmatic, cluster-randomised trial

BACKGROUND

Highly effective direct-acting antiviral drugs provide the opportunity to eliminate hepatitis C virus (HCV) infection, but established pathways can be ineffective. We aimed to examine whether a community pharmacy care pathway increased treatment uptake, treatment completion, and cure rates for people receiving opioid substitution therapy, compared with conventional care.

METHODS

This cluster-randomised trial was done in Scottish community pharmacies. Before participants were recruited, pharmacies were randomly assigned (1:1) to refer patients with evidence of HCV antibodies to conventional care or offered them care in the pharmacy (pharmacist-led care). Pharmacies were stratified by location. All pharmacies were trained to offer dried blood spot testing. All eligible participants had received opioid substitution therapy for approximately 3 months, and those eligible to receive treatment in the pharmacist-led care pathway were HCV PCR positive, were infected with HCV genotype 1 or 3, and were willing to have a pharmacist supervise their antiviral drug administration. Neither pharmacists nor patients were masked to treatment allocation. In both groups, assessment blood samples were taken, infection with HCV was confirmed, and daily oral ledipasvir-sofosbuvir (90 mg ledipasivir plus 400 mg sofosbuvir) for 8 weeks for genotype 1 or daily oral sofosbuvir (400 mg) plus oral daclatasvir (60 mg) for 12 weeks for genotype 3 was prescribed by a nurse (conventional care group) or pharmacist (pharmacist-led care group). In the conventional care group, the patient received care at a treatment centre. Once prescribed, medication in both groups was delivered as daily modified directly observed therapy alongside opioid substitution therapy in the participants' pharmacy where treatment was observed on 6 days per week. The primary outcome was the number of patients with sustained virological response 12 weeks after completion of treatment (SVR12) as a proportion of the number of people receiving opioid substitution therapy at participating pharmacies. Participants were monitored at each visit for nausea and fatigue; other adverse events were recorded as free text. Secondary outcomes compared key points on treatment pathway between the two groups. These key points were the proportion of patients having dry blood spot testing, the proportion of patients initiating HCV treatment, the proportion of patients completing the 8 or 12 week HCV course of treatment, and the proportion of patients with sustained virological response at 12 months. This study is registered with ClinicalTrials.gov, NCT02706223.

FINDINGS

56 pharmacies were randomly assigned (28 to each group; one pharmacy withdrew from the conventional care group). The 55 participating pharmacies included 2718 patients receiving opioid substitution therapy (1365 in the pharmacist-led care group and 1353 in the conventional care group). More patients met the primary endpoint of SVR12 in the pharmacist-led care group (98 [7%] of 1365) than in the conventional care group (43 [3%] of 1353; odds ratio 2·375, 95% CI 1·555-3·628, p<0·0001). More users of opioid substitution therapy in the pharmacist-led care group versus the conventional care group agreed to dry blood spot testing (245 [18%] of 1365 vs 145 [11%] of 1353, 2·292, 0·968-5·427, p=0·059); initiated treatment (112 [8%] of 1365 vs 61 [4%] of 1353, 1·889, 1·276-2·789, p=0·0015) and completed treatment (108 [8%] of 1365 vs 58 [4%] of 1353, 1·928, 1·321-2·813, p=0·0007). The data for sustained virological response at 12 months are not reported in this study: patients remain in follow-up for this outcome. No serious adverse events were recorded.

INTERPRETATION

Using pharmacists to deliver an HCV care pathway made testing and treatment more accessible for patients, improved engagement, and maintained high treatment success rates. The use of this pathway could be a key part of an integrated and effective approach to HCV elimination at a community level.

FUNDING

Partnership between the Scottish Government, Gilead Sciences, and Bristol-Myers Squib.