Effectiveness of treatment for hepatitis C virus reinfection following direct acting antiviral therapy in the REACH-C cohort

Hepatitis C (HCV) Reinfection and Risk Factors among Clients of a Low-Threshold Primary Healthcare Service for People Who Inject Drugs in Sydney, Australia

Hepatitis C (HCV) reinfection studies have not focused on primary healthcare services in Australia, where priority populations including people who inject drugs (PWID) typically engage in healthcare. We aimed to describe the incidence of HCV reinfection and associated risk factors in a cohort of people most at risk of reinfection in a real-world community setting. We conducted a secondary analysis of routinely collected HCV testing and treatment data from treatment episodes initiated with direct-acting antiviral (DAA) therapy between October 2015 and June 2021. The overall proportion of clients (N = 413) reinfected was 9% (N = 37), and the overall incidence rate of HCV reinfection was 9.5/100PY (95% CI: 6.3-14.3). Reinfection incidence rates varied by sub-group and were highest for Aboriginal and/or Torres Strait Islander people (20.4/100PY; 95% CI: 12.1-34.4). Among PWID (N= 321), only Aboriginality was significantly associated with reinfection (AOR: 2.73, 95% CI: 1.33-5.60, p = 0.006). High rates of HCV reinfection in populations with multiple vulnerabilities and continued drug use, especially among Aboriginal and Torres Strait Islander people, highlight the need for ongoing regular HCV testing and retreatment in order to achieve HCV elimination. A priority is resourcing testing and treatment for Aboriginal and/or Torres Strait Islander people. Our findings support the need for novel and holistic healthcare strategies for PWID and the upscaling of Indigenous cultural approaches and interventions.

Direct-acting antiviral therapies for hepatitis C infection: global registration, reimbursement, and restrictions

Direct-acting antivirals (DAAs) for hepatitis C virus (HCV) infection have delivered high response rates (>95%) and simplified the management of HCV treatment, permitting non-specialists to manage patients without advanced liver disease. We collected and reviewed global data on the registration and reimbursement (government subsidised) of HCV therapies, including restrictions on reimbursement. Primary data collection occurred between Nov 15, 2021, and July 24, 2023, through the assistance of a global network of 166 HCV experts. We retrieved data for 160 (77%) of 209 countries and juristrictions. By mid-2023, 145 (91%) countries had registered at least one of the following DAA therapies: sofosbuvir-velpatasvir, sofosbuvir-velpatasvir-voxilaprevir, glecaprevir-pibrentasvir, sofosbuvir-daclatasvir, or sofosbuvir. 109 (68%) countries reimbursed at least one DAA therapy. Among 102 low-income and middle-income countries (LMICs), 89 (87%) had registered at least one HCV DAA therapy and 53 (52%) reimbursed at least one DAA therapy. Among all countries with DAA therapy reimbursement (n=109), 66 (61%) required specialist prescribing, eight (7%) had retreatment restrictions, seven (6%) had an illicit drug use restriction, five (5%) had an alcohol use restriction, and three (3%) had liver disease restrictions. Global access to DAA reimbursement remains uneven, with LMICs having comparatively low reimbursement compared with high-income countries. To meet WHO goals for HCV elimination, efforts should be made to assist countries, particularly LMICs, to increase access to DAA reimbursement and remove reimbursement restrictions-especially prescriber-type restrictions-to ensure universal access.

Direct-Acting Antivirals Remain Cost-Effective Treatments for Chronic Hepatitis C in Australia Despite Changes to the Treated Population and the Availability of Retreatment: The Glecaprevir/Pibrentasvir (Maviret®) Example

INTRODUCTION

The first direct-acting antiviral (DAA) therapies for chronic hepatitis C virus (HCV) infection were reimbursed via Australia's Pharmaceutical Benefits Scheme (PBS) in March 2016. This was based on the recommendation from the Pharmaceutical Benefits Advisory Committee (PBAC) that the regimens would be acceptably cost-effective at an incremental cost-effectiveness ratio (ICER) no greater than $15,000/quality-adjusted life-year (QALY). Since the initial PBS listings for DAA therapies and subsequent listings of newer DAA treatments such as glecaprevir/pibrentasvir (Maviret®), the demographics and some of the disease characteristics of currently treated patients have markedly changed. This analysis aims to reassess the cost-effectiveness of glecaprevir/pibrentasvir, accounting for the changes to the HCV population currently seeking treatment and incorporating retreatment in first-line failures and the treatment of new infections in previously treated individuals.

METHODS

To assess the cost-effectiveness 7 years after initial listing of DAAs, an update was made to the Markov model used to achieve PBS reimbursement for Viekira-Pak® in May 2016. Amendments to the Viekira-Pak® model include: changes to baseline age and fibrosis distribution of treated patients, and inclusion of retreatment of first-line failures [those not achieving a sustained virologic response (SVR12)] and reinfected individuals. Treatment-related inputs including SVR12 response rates, adverse events, treatment-related disutility, and discontinuations were sourced from pivotal glecaprevir/pibrentasvir clinical trials.

RESULTS

Using the published price of glecaprevir/pibrentasvir, the ICER is below $15,000/QALY.

CONCLUSIONS

Despite changes in demographics and disease characteristics of treated patients, and changes to the model structure to reflect retreatment in clinical practice in Australia, DAAs remain cost-effective in 2023.

Public reimbursement policies in Canada for direct-acting antiviral treatment of hepatitis C virus infection: A descriptive study

Background

Direct-acting antiviral (DAA) therapies have simplified HCV treatment, and publicly funded Canadian drug plans have eliminated disease-stage restrictions for reimbursement of DAA therapies. However other policies which complicate, delay, or prevent treatment initiation still persist. We aim to describe these plans' existing reimbursement criteria and appraise whether they hinder treatment access.

Methods

We reviewed DAA reimbursement policies of 16 publicly funded drug plans published online and provided by contacts with in-depth knowledge of prescribing criteria. Data were collected from May to July 2022. Primary outcomes were: (1) if plans have arranged to accept point-of-care HCV RNA testing for diagnosis; testing requirements for (2) HCV genotype, (3) fibrosis stage, and (4) chronic infection; (5) time taken and method used to approve reimbursement requests; (6) providers eligible to prescribe DAAs; and (7) restrictions on re-treatment.

Results

Fifteen (94%) plans have at least one policy in place which limits simplified HCV treatment. Many plans continue to require results of genotype or fibrosis staging, limit eligible prescribers, and take longer than 1 day to approve coverage requests. One plan discourages treatment for re-infection.

Conclusion

Reimbursement criteria set by publicly funded Canadian drug plans continue to limit timely, equitable access to HCV treatment. Eliminating clinically irrelevant pre-authorization testing, expanding eligible prescribers, expediting claims processing, and broadening coverage of treatment for reinfection will improve access to DAAs. The federal government could further enhance efforts by introducing a federal HCV elimination strategy or federal high-cost drug PharmaCare program.

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

BACKGROUND & AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

IMPACT AND IMPLICATIONS

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

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.

HCV elimination in a Swiss opioid agonist therapy programme - a cohort study

BACKGROUND

In opioid agonist therapy (OAT) programmes, chronic hepatitis C is highly prevalent and directly observed therapy guarantees optimal adherence. Since 2017, all patients with chronic hepatitis C in Switzerland can be treated with pangenotypic direct-acting antivirals irrespective of liver fibrosis stage. Until the end of 2021, however, prescription was restricted to infectious disease specialists, gastroenterologists and certain addiction specialists. Difficult venous access after long-term intravenous drug use and, in the case of referral to a specialist, difficulties keeping appointments are barriers to HCV diagnosis and treatment.

AIMS

To assess whether minimally invasive point-of-care tests and a "test-and-treat / vaccinate on-site" approach can improve human immunodeficiency virus (HIV) / hepatitis C virus (HCV) screening, HCV treatment uptake and immunity against hepatitis A/B.

METHODS

Since September 2018, an infectious disease specialist and a study nurse performed 4-weekly visits in the OAT programme "HAG" (heroin dispensation of the canton Aargau), offering HIV/HCV antibody rapid testing (20 min) and HCV RNA quantification (GeneXpert®, 60 min) from capillary blood, noninvasive liver fibrosis assessment (Fibroscan®, 5-10 min) and HCV treatment prescription on-site. Recommended venous blood draws for HAV/HBV serology and HAV/HBV vaccinations were performed by the staff of the "HAG". Project performance was assessed by annual cross-sectional chart review.

RESULTS

Of the 128 patients registered in April 2018, 79 (62%) were still present in May 2021. With 72 newly registered, a total of 200 patients could be assessed, of whom 129 (65%) were still present in May 2021. Between April 2018 and May 2021, the proportion ever tested for HIV antibodies increased from 79% (101/128) to 91% (117/129), the proportion ever tested for HCV antibodies from 83% (106/128) to 93% (120/129) and the proportion of those HCV antibody positive ever tested for HCV RNA tested from 89% (47/53) to 98% (56/57). The proportion with adequate HCV management (last HCV antibody test ≤1 year ago, if HCV antibody negative or last HCV RNA test ≤1 year ago, if HCV antibody-positive and RNA-negative) improved from 23% ([15 + 15]/128) to 80% ([55 + 48]/129). Overall, HCV treatment uptake increased from 60% (21/35) to 92% (55/60) and HCV RNA prevalence among the HCV antibody positives decreased from 38% (18/47) to 7% (6/84). Between 2018 and 2021, 19 non-cirrhotic chronic hepatitis C patients were successfully treated on-site (18 sustained virological responses [SVR] 12, 1 SVR4), with excellent adherence (≥93%) and, so far, no reinfection. The proportion with known HAV/HBV serostatus increased from 38%/51% to 64%/76%. Immunity against HAV/HBV improved from 19%/23% to 50%/57%.

CONCLUSION

Capillary blood point-of-care tests and a "test-and-treat / vaccinate on-site" approach remove crucial barriers to diagnosis and treatment, making hepatitis elimination in OAT programmes achievable. A high fluctuation rate requires HIV/HCV/HAV/HBV testing at admission, but also allows more patients to be screened.

Awareness of HCV Status and Preferences for Testing and Treatment among People with Recent Injecting Drug Use at a Peer-Led Needle and Syringe Program: The TEMPO Pilot Study

BACKGROUND

New technologies and therapies allow the possibility of a single-visit test and treat model for hepatitis C virus (HCV), addressing some of the barriers to care faced by people who inject drugs.

METHODS

The TEMPO Pilot Study was an interventional cohort study evaluating a single-visit test and treat intervention among people with recent injecting drug use at a one peer-led needle and syringe program (NSP) in Sydney, Australia between September 2019 and February 2021. This analysis evaluated awareness of HCV status and agreement of self-report with HCV RNA test results. The analysis also assessed acceptability of: modality of result delivery, modality of blood sampling, site of treatment, and duration of treatment.

RESULTS

Among 101 participants (median age 43; 31% female), 100 had a valid HCV RNA test result and 27% (27/100) were HCV RNA detectable. Overall, 65% (65/100) were aware of their status. Among people with a positive HCV RNA result, 48% (13/27) were aware of their status. People preferred same-day HCV test results (95%, 96/101), and preferred to receive results in person (69%, 70/101). Receiving treatment at an NSP was acceptable (100%, 101/101) and 78% (79/101) were willing to discuss their health with a peer NSP worker.

CONCLUSION

Half of people with current HCV infection were aware of their status. The high acceptability of simplified testing and treatment pathways delivered at NSPs indicates that this is an appropriate strategy to improve HCV awareness and treatment uptake in this population.

Chronic Viral Hepatitis in Elite Athletes: Approaches to Risk Assessment, Prevention and Management

Elite athletes who participate in contact sports are at risk of bleeding injuries, leading to transmission of blood-borne viruses including hepatitis type B, C and D (HBV, HCV and HDV) capable of causing chronic liver disease, liver failure and liver cancer. In view of the significant advances in the viral hepatitis field over the past decade, more structured approaches should be in place to screen for and manage viral hepatitis in elite athletes. HBV status should be assessed in all elite athletes, and those infected should receive nucleos(t)ide analogues for viral suppression, while uninfected individuals should receive HBV vaccination. The all-oral direct acting antivirals for HCV are highly effective and safe, thus the remaining challenge with hepatitis C is case identification and linkage to care. HDV is only found in HBV-infected individuals, which is characterized by rapid disease progression and higher rates of cirrhosis and liver cancer in infected subjects. Pegylated interferon was the mainstay of treatment for HDV infection until bulevirtide, a viral entry inhibitor, was recently approved by the European Union (EMA) and FDA in America, while multiple novel therapies are already in clinical trials as part of the HBV cure program. Overall, awareness of chronic viral hepatitis in athletes should be improved. Prevention remains the cornerstone of the management of viral hepatitis in sport coupled with rigorous disease assessment in infected individuals, and antiviral therapy where indicated.

Perceptions of hepatitis C treatment and reinfection risk among HIV-positive men who have sex with men and engage in high risk behaviours for hepatitis C transmission: The CEASE qualitative study

BACKGROUND

Globally, treatment uptake for hepatitis C virus (HCV) infection among HIV-HCV coinfected men who have sex with men (MSM) has substantially increased since the advent of interferon-free direct-acting antivirals (DAA). However, HIV-positive MSM who engage in high risk behaviours are at an increased risk of HCV reinfection post-treatment. The aim of this study was to investigate perceptions of HCV diagnosis, treatment and reinfection risk among HCV-HIV coinfected MSM who engage in drug use and/or high risk sexual behavior in Sydney, Australia.

METHODS

Participants were recruited from the Control and Elimination within AuStralia of HEpatitis C from people living with HIV (CEASE) cohort (n=402) who reported engaging in drug use and/or high risk sexual behavior for transmission of HCV infection. Participants were interviewed about their perceptions of HCV diagnosis, treatment, and reinfection risk. Interview data were transcribed, coded, and analyzed thematically.

RESULTS

Of 33 participants interviewed (mean age 49 years), many participants were 'shocked' by their HCV diagnosis. Participants who believed they acquired HCV infection through sexual exposure felt it was important that their healthcare practitioner agreed with their perspective to mitigate stigmatizing experiences. Overall, participants expressed high satisfaction with their treatment experience due to long-standing therapeutic relationships with their HIV physician. Many participants expressed knowledge of how to prevent HCV reinfection from injection drug use, yet other than condom usage, most were unsure how to reduce high risk sexual activity with such discussions occurring less frequently with healthcare practitioners.

CONCLUSION

Findings indicate that MSM who engage in drug use and high risk sexual activity would benefit from additional education on reducing reinfection risk through sexual activity and services to reduce substance use, if requested.

Hepatitis C virus reinfection in people living with human immunodeficiency virus in Taiwan after achieving sustained virologic response with antiviral treatment: the RECUR study

Background

Data on hepatitis C virus (HCV) reinfection in East Asian people living with human immunodeficiency virus (HIV) after treatment-induced sustained virologic response (SVR) are limited.

Methods

HIV/HCV-coinfected patients in Taiwan who achieved SVR12 with interferon (IFN) or direct-acting antivirals (DAAs) between 2005 and 2021 underwent HCV RNA measurements at SVR24 and then biannually. HCV reinfection was defined as the detection of different HCV strains beyond SVR12. HIV-negative, low-risk individuals with SVR12 served as reference patients. Crude reinfection rates and secular trends were assessed. Multivariate Cox regression analysis was performed to identify baseline factors associated with HCV reinfection.

Results

A total of 216 HIV-positive and 1589 reference patients were recruited with median follow-up durations of 3.0 and 6.0 years. During a total of 772 person-years of follow-up (PYFU), the HCV reinfection rate in HIV-positive patients was 4.02 per 100 PYFU (95% confidence interval [CI]: 2.85-5.65), while the HCV reinfection rate in reference patients was 0.14 per 100 PYFU (95% CI: 0.09-0.23) during 10862 PYFU. HIV-positive patients had a higher risk of HCV reinfection than reference patients (hazard ratio [HR]: 17.63; 95% CI: 7.10-43.80, p &lt; 0.001). No baseline factors were predictive of HCV reinfection in HIV-positive patients. The incidence of HCV reinfection in HIV-positive patients increased after 2015 when DAAs were available in Taiwan.

Conclusions

The risk of HCV reinfection remains high in HIV/HCV-coinfected patients with treatment-induced SVR12. In addition to mass screening and treatment scale-up, strategies to reduce reinfection are needed for HCV microelimination in HIV-positive patients in Taiwan.

Hepatitis C virus reinfection following direct acting antiviral treatment in the prison setting: the SToP-C study

BACKGROUND

Injection drug use (IDU) following treatment for hepatitis C virus (HCV) may lead to reinfection, particularly if access to harm reduction services is suboptimal. This study assessed HCV reinfection risk following direct-acting antiviral therapy within Australian prisons that had opioid agonist therapy (OAT) programs but did not have needle and syringe programs (NSP).

METHODS

The Surveillance and Treatment of Prisoners with hepatitis C (SToP-C) study enrolled people incarcerated in four prisons between 2014-2019. Participants treated for HCV were followed every 3-6 months to identify reinfection (confirmed by sequencing). Reinfection incidence and associated factors were evaluated.

FINDINGS

Among 388 participants receiving treatment, 161 had available post-treatment follow-up and were included in analysis (92% male; median age 33 years; 67% IDU in prison; median follow-up 9 months). Among those with recent (in the past month) IDU (n=71), 90% had receptive needle/syringe sharing. During 145 person-years (PY) of follow-up, 18 cases of reinfection were identified. Reinfection incidence was 12.5/100 PY (95%CI: 7.9-19.8) overall, increasing to 28.7/100 PY; (95%CI 16.3-50.6) among those with recent IDU and needle/syringe sharing. In adjusted analysis, recent IDU with needle/syringe sharing was associated with increased reinfection risk (adjusted hazard ratio [AHR] 14.62; 95%CI 1.84-116.28; p=0.011) and longer HCV testing interval with decreased risk (i.e., chance of detection; AHR 0.41 per each month increase; 95%CI 0.26-0.64; p<0.001).

CONCLUSION

A high rate of HCV reinfection was observed within prison. Post-treatment surveillance and retreatment are essential to limit the impact of reinfection. High-coverage OAT and NSP should be considered within prisons.