Diagnostic accuracy of assays using point-of-care testing or dried blood spot samples for the determination of HCV RNA: a systematic review

Challenges and Opportunities for Treating Hepatitis C Amongst People Who Use Drugs: Experience of an Integrated Mobile Clinic in Baltimore City

Progress in treating chronic hepatitis C virus (HCV) infection has been slow amongst people who use drugs (PWUD). This study describes the HCV treatment cascade amongst people accessing a mobile clinic offering integrated low-threshold buprenorphine and infectious disease services in Baltimore City. From May 1, 2021, to December 31, 2022, 560 people had a rapid HCV antibody test, of whom 201 (36%) had a positive result and amongst those, 117 (58%) had an HCV RNA test performed, 81 (40%) had a documented positive RNA, 45 (22%) were prescribed medication, 42 (21%) started medication, 32 (16%) completed medication, 22 (11%) had blood work to assess for sustained virologic response and 20 (10%) had a documented cure. Challenges including housing instability, insurance barriers and lack of venous access limit progress in this cascade. Providing integrated care models to meet the needs of PWUD in the community is necessary but not sufficient to make progress in improving HCV treatment. Removal of insurance restrictions, availability of point-of-care HCV RNA testing, development of rapid HCV treatment guidelines and development of long-acting injectable HCV treatment are needed to move towards a same-day, one-time test and treat model of care.

Virological markers for clinical trials in chronic viral hepatitis

Chronic hepatitis virus infections remain a major public health problem, despite significant therapeutic advances over the past two decades. Considerable progress has been made in the treatment of chronic viral hepatitis, but continued efforts are needed to develop and bring to market new drugs to fill the gaps in the current therapeutic armamentarium. Thus, clinical trials to assess the safety and efficacy of these new therapeutic approaches, including the selection of reliable and objective treatment endpoints, are still needed. Virological biomarkers play an important role in the diagnosis, monitoring, and evaluation of antiviral treatment efficacy. They are often used as primary or secondary endpoints in the evaluation of new treatments for chronic viral hepatitis. However, these markers are not all equally informative. The aim of this review article is to provide a comprehensive overview of the available virological tests for chronic viral hepatitis due to hepatitis B, D, C and E viruses, the information they provide and lack, the specific challenges associated with each, and their use in clinical trials of new treatments.

Point-of-Care Testing for Hepatitis C in the Priority Settings of Mental Health, Prisons, and Drug and Alcohol Facilities-the PROMPt Study

BACKGROUND

A barrier to hepatitis C virus (HCV) cure is conventional testing. The aim of this study was to evaluate the effect of HCV antibody and RNA point-of-care testing (POCT) on testing rates, linkage to care, treatment, and acceptability of testing in 3 priority settings in Australia.

METHODS

Participants were enrolled in an interventional cohort study at a reception prison, inpatient mental health service, and inpatient alcohol and other drug unit, between October 2020 and December 2021. HCV POCT was performed using SD Bioline HCV antibody fingerstick test and a reflexive Xpert HCV Viral Load Fingerstick test using capillary blood samples. A retrospective audit of HCV testing and treatment data was performed at each site for the preceding 12-month period to generate a historical control.

RESULTS

A total of 1549 participants received a HCV antibody test with 17% (264 of 1549) receiving a positive result, of whom 21% (55 of 264) tested HCV RNA positive. Across all settings the rate of testing per year significantly increased between the historical controls and the study intervention period by 2.57 fold (rate ratio, 2.57 [95% confidence interval, 2.32-2.85]) for HCV antibody testing and 1.62 (rate ratio, 1.62 [95% confidence interval, 1.31-2.01]) for RNA testing. Treatment uptake was higher during the POCT intervention (86% [47 of 55]; P = .01) compared to the historical controls (61% [27 of 44]).

CONCLUSIONS

This study demonstrated across 3 settings that the use of HCV antibody and RNA POCT increased testing rates, treatment uptake, and linkage to care. The testing model was highly acceptable for most participants.

CLINICAL TRIALS REGISTRATION

ACTRN-12621001578897.

Diagnostic performance of dried blood spot hepatitis C virus core antigen testing for hepatitis C screening: A systematic review and meta-analysis

Dried blood spot (DBS) sampling is increasingly used for hepatitis C virus (HCV) screening. HCVcAg testing offers a faster and more streamlined approach to diagnosing HCV infection. We conducted a systematic review and meta-analysis to assess the diagnostic performance of the Abbott ARCHITECT HCV Ag assay for screening active HCV infection using DBS samples. Eight studies (n = 1229) were selected among all published studies available up to October 4, 2024, in different databases with a search strategy registered (PROSPERO: CRD42022363975). The gold standard method was the HCV PCR test. Data were analyzed using the MIDAS module in STATA with a random effects model. Combined diagnostic accuracy measures were as follows: sensitivity 85%, specificity 100%, positive likelihood ratio (PLR) 233.1, negative likelihood ratio (NLR) 0.15, and summary receiver operating characteristic (SROC) 0.99. Likelihood ratios and Fagan's nomogram suggested that the HCVcAg assay with DBS samples can confirm or rule out active HCV infection with over 92% accuracy in high-prevalence settings (≥5%). However, in low-prevalence settings (≤1%), a confirmatory test must be required for positive results. The ability of the test to identify people without HCV infection was high regardless of HCV prevalence, with an error rate of less than 3%. This meta-analysis is subject to limitations, particularly due to the number of included studies and significant heterogeneity among them. HCV screening using the Abbott ARCHITECT HCV Ag assay with DBS samples showed excellent diagnostic performance, but its external validity may be limited when HCV prevalence is low (≤1%).

The Urgent Need to Implement Point-of-Care RNA Testing for Hepatitis C Virus to Support Elimination

Hepatitis C virus (HCV) elimination is an important global public health goal. However, the United States is not on track to meet the World Health Organization's 2030 targets for HCV elimination. Recently, the White House proposed an HCV elimination plan that includes point-of-care (POC) HCV RNA testing, which is currently in use in many countries but is not approved in the United States. POC HCV RNA testing is crucial for implementing community-based testing and for enabling test-and-treat programs, assessing cure, and monitoring for reinfection. Here, we review the status of POC HCV RNA testing in the United States, discuss factors that are needed for successful implementation, and issue specific public health and policy recommendations that would allow for the use of POC HCV RNA testing to support HCV elimination.

What Is Needed to Move Toward Single-Step Diagnosis of Current HCV Infection?

Despite remarkable therapeutic advances, hepatitis C virus (HCV) infection continues to be a major global problem. While the development of highly effective direct-acting antivirals has ensured that almost all those who are treated achieve viral cure, progress toward HCV elimination globally has stalled due to challenges upstream of treatment in the cascade of care, namely diagnosis and linkage to care. The major challenge continues to be the relative complexity of HCV diagnosis with the current requirement for a confirmatory HCV RNA test after an initial antibody-positive result. In this review, challenges with the current paradigm are highlighted with a focus on new technologies, as well as simple strategies using existing tools, which may simplify diagnosis and improve linkage to care and treatment. To achieve HCV elimination, improvements in the HCV diagnostics field to allow for a simple single-step diagnosis are required.

Challenges and facilitators in repeated bio-behavioural surveys for blood-borne virus infections in Australian prisons

BACKGROUND

Prison-based blood-borne virus (BBV) surveillance is essential for evaluation of prevention and treatment programs for high-risk populations, such as people who inject drugs who are over-represented amongst those incarcerated. Regular triennial surveillance has been in place in Australian prisons for almost two decades, but has been focused to date only on new prison entrants. Recently, the Australian Hepatitis and risk survey in prisons (AusHep study) was established to provide improved surveillance via an expanded bio-behavioural survey representative of all people in prison, including those sentenced and those on remand. This paper aims to identify the challenges and facilitators in conducting bio-behavioural surveys for BBV infections in prison settings.

METHODS

Randomly selected individuals in 23 prisons, representative of prisons and people in prison (male/female, security classification, rural location, Aboriginal or Torres Strait Islander), were offered point-of-care testing for HIV and hepatitis C (HCV) antibodies, hepatitis B virus surface (HBs) antigen, and HCV RNA (if HCV antibody positive). Data regarding risk behaviours, harm reduction measures, and prior BBV testing and treatment were collected by interview. Data was also collected on the challenges and facilitators encountered during planning and implementation at each participating prison.

RESULTS

In the first round, AusHep recruited 1599 participants (98 % participation, 89 % male, median age 35 years, 49 % ever injected drugs). Major implementation challenges included: slow and complex ethics and governance requirements in each jurisdiction, and challenging logistical arrangements and participant access constraints in the prisons. Major facilitators included use of point-of-care testing allowing immediate feedback of results, strong support from jurisdictional stakeholders in correction and public health sectors, flexibility in the timing and detailed planning for each site, and computer tablet-based data collection.

CONCLUSION

The high participation and informative findings indicated clear feasibility of this improved surveillance system. Strong stakeholder engagement and flexibility in logistics facilitated successful implementation of multi-jurisdictional prison-based surveillance.

We have reached single-visit testing, diagnosis, and treatment for hepatitis C infection, now what?

INTRODUCTION

Progress toward hepatitis C virus (HCV) elimination is impeded by low testing and treatment due to the current diagnostic pathway requiring multiple visits leading to loss to follow-up. Point-of-care testing technologies capable of detecting current HCV infection in one hour are a 'game-changer.' These tests enable diagnosis and treatment in a single visit, overcoming the barrier of multiple visits that frequently leads to loss to follow-up. Combining point-of-care HCV antibody and RNA tests should improve cost-effectiveness, patient/provider acceptability, and testing efficiency. However, implementing HCV point-of-care testing programs at scale requires multiple considerations.

AREAS COVERED

This commentary explores the need for point-of-care HCV tests, diagnostic strategies to improve HCV testing, key considerations for implementing point-of-care HCV testing programs, and remaining challenges for point-of-care testing (including operator training, quality management, connectivity and reporting systems, regulatory approval processes, and the need for more efficient tests).

EXPERT OPINION

It is exciting that single-visit testing, diagnosis, and treatment for HCV infection have been achieved. Innovations afforded through COVID-19 should facilitate the accelerated development of low-cost, rapid, and accurate tests to improve HCV testing. The next challenge will be to address barriers and facilitators for implementing point-of-care testing to deliver them at scale.

Point-of-care HCV RNA testing improves hepatitis C testing rates and allows rapid treatment initiation among people who inject drugs attending a medically supervised injecting facility

BACKGROUND

To achieve hepatitis C virus (HCV) elimination targets, simplified care engaging people who inject drugs is required. We evaluated whether fingerstick HCV RNA point-of-care testing (PoCT) increased the proportion of clients attending a supervised injecting facility who were tested for hepatitis C.

METHODS

Prospective single-arm study with recruitment between 9 November 2020 and 28 January 2021 and follow-up to 31 July 2021. Clients attending the supervised injecting facility were offered HCV RNA testing using the Xpert® HCV Viral Load Fingerstick (Cepheid, Sunnyvale, CA) PoCT. Participants with a positive HCV RNA test were prescribed direct acting antiviral (DAA) therapy. The primary endpoint was the proportion of clients who engaged in HCV RNA PoCT, compared to a historical comparator group when venepuncture-based hepatitis C testing was standard of care.

RESULTS

Among 1618 clients who attended the supervised injecting facility during the study period, 228 (14%) engaged in PoCT. This was significantly higher than that observed in the historical comparator group (61/1,775, 3%; p < 0.001). Sixty-five (28%) participants were HCV RNA positive, with 40/65 (62%) receiving their result on the same day as testing. Sixty-one (94%) HCV RNA positive participants were commenced on DAA therapy; 14/61 (23%) started treatment on the same day as diagnosis. There was no difference in the proportion of HCV RNA positive participants commenced on treatment with DAA therapy when compared to the historical comparator group (61/65, 94% vs 22/26, 85%; p = 0.153). However, the median time to treatment initiation was significantly shorter in the PoCT cohort (2 days (IQR 1-20) vs 41 days (IQR 22-76), p < 0.001). Among participants who commenced treatment and had complete follow-up data available, 27/36 (75%) achieved hepatitis C cure.

CONCLUSIONS

HCV RNA PoCT led to a significantly higher proportion of clients attending a supervised injecting facility engaging in hepatitis C testing, whilst also reducing the time to treatment initiation.

Testing, diagnosis, and treatment following the implementation of a program to provide dried blood spot testing for HIV and hepatitis C infections: the NSW DBS Pilot

BACKGROUND

Dried blood spot (DBS) testing provides an alternative to phlebotomy and addresses barriers to accessing healthcare experienced by some key populations. Large-scale evaluations of DBS testing programs are needed to understand their feasibility. This study evaluated the implementation of a state-wide DBS HIV and hepatitis C virus (HCV) testing pilot.

METHODS

The New South Wales (NSW) DBS Pilot is an interventional cohort study of people testing for HIV antibody and/or HCV RNA from DBS samples in NSW, Australia. Participants at risk of HIV/HCV participated in testing via: 1) self-registration online with a DBS collection kit delivered and returned by conventional postal service; or 2) assisted DBS sample collection at 36 community health sites (including drug treatment and harm-minimisation services) and prisons. Participants received results by text (HIV antibody/ HCV RNA not detected) or a healthcare provider (HIV antibody/ HCV RNA detected). The RE-AIM framework was used to evaluate reach, effectiveness, adoption, and implementation.

RESULTS

Reach: Between November 2016 and December 2020, 7,392 individuals were tested for HIV and/or HCV (21% self-registration, 34% assisted in community, and 45% assisted in prison).

EFFECTIVENESS

Of 6,922 people tested for HIV (19% men who have sex with men, 13% living outside major cities, 21% born outside Australia), 51% (3,521/6,922) had no HIV test in the past two years, 0.1% (10/6,922) were newly diagnosed with HIV, and 80% (8/10) initiated HIV treatment within six months. Of 5,960 people tested for HCV (24% women, 35% Aboriginal and/or Torres Strait Islander, 55% recently injected drugs), 15% had detectable HCV RNA (878/5,960), and 45% (393/878) initiated treatment within six months. Adoption: By the end of 2020, DBS via assisted registration was available at 36 community sites and 21 prisons.

IMPLEMENTATION

90% of DBS cards arriving at the laboratory had the three full spots required for testing; the proportion was higher in assisted (94%) compared to online (76%) registration.

CONCLUSIONS

This study demonstrated the feasibility of DBS testing for HIV and HCV in key populations including Aboriginal and Torres Strait Islander peoples, men who have sex with men, people who inject drugs, and demonstrated the utility of DBS in the prison setting.

Point-of-Care Testing for Hepatitis Viruses: A Growing Need

Viral hepatitis, caused by hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV), or hepatitis E virus (HEV), is a major global public health problem. These viruses cause millions of infections each year, and chronic infections with HBV, HCV, or HDV can lead to severe liver complications; however, they are underdiagnosed. Achieving the World Health Organization's viral hepatitis elimination goals by 2030 will require access to simpler, faster, and less expensive diagnostics. The development and implementation of point-of-care (POC) testing methods that can be performed outside of a laboratory for the diagnosis of viral hepatitis infections is a promising approach to facilitate and expedite WHO's elimination targets. While a few markers of viral hepatitis are already available in POC formats, tests for additional markers or using novel technologies need to be developed and validated for clinical use. Potential methods and uses for the POC testing of antibodies, antigens, and nucleic acids that relate to the diagnosis, monitoring, or surveillance of viral hepatitis infections are discussed here. Unmet needs and areas where additional research is needed are also described.

Development of simple, rapid, and sensitive methods for detection of hepatitis C virus RNA from whole blood using reverse transcription loop-mediated isothermal amplification

Hepatitis C virus (HCV) infection is an underdiagnosed global health problem. Diagnosis of current HCV infections typically requires testing for HCV RNA using high-complexity laboratory tests. Methods for the detection of HCV RNA that are simple, inexpensive, rapid, and compatible with use outside of a laboratory setting are very important in order to improve access to hepatitis C diagnostic testing and facilitate accelerated linkage to care. We developed and evaluated three simple workflows for extracting HCV RNA from small volumes of whole blood for use in a sensitive, pan-genotypic RT-LAMP assay. The water workflow uses osmotic stress to release HCV RNA and has a limit of detection of 4.3 log10(IU/mL) (95% CI 4.0-4.9). The heat workflow uses a heating step to release HCV RNA and has a limit of detection of 4.2 log10(IU/mL) (95% CI 3.8-5.1). The bead workflow, which uses chemical lysis of the sample and a streamlined paramagnetic solid phase reversible immobilization bead procedure for nucleic acid purification, has a limit of detection of 2.8 log10(IU/mL) (95% CI 2.5-3.4). When used to test whole blood spiked with HCV RNA-positive plasma samples in which most HCV levels were below 5.0 log10(IU/mL), the water, heat, and bead workflows detected HCV RNA in 69%, 75%, and 94% of samples, respectively. These workflows are compatible with visual lateral flow dipsticks, and each takes less than 60 min from sample to result. Each workflow can be performed with minimal and inexpensive equipment. With further procedural simplifications, these workflows may form the basis of assays for the point-of-care diagnosis of HCV infections.

Hepatitis C Treatment Uptake Following Dried Blood Spot Testing for Hepatitis C RNA in New South Wales, Australia: The NSW DBS Pilot Study

Background

Dried blood spot (DBS) testing for hepatitis C virus (HCV) RNA provides a sampling option that avoids venepuncture and can be carried out in a nonclinical setting. Large-scale evaluations are needed to understand how DBS testing can reduce HCV burden. This study estimated prevalence of, and factors associated with, HCV RNA and treatment initiation among people enrolled in a state-wide pilot of people testing in the NSW DBS Pilot in New South Wales, Australia.

Methods

People at risk of HIV/HCV could participate via (1) self-registration online with a DBS collection kit delivered and returned by conventional postal service; or (2) assisted DBS sample collection at a community site or prison. Logistic regression was used to identify factors associated with detectable HCV RNA and treatment initiation within 6 months of testing.

Results

Between September 2017 and December 2020, 5960 people were tested for HCV (76% men, 35% Aboriginal and/or Torres Strait Islander, 55% recently injected drugs): 21% online self-registration, 34% assisted registration in the community, 45% assisted registration in prison. Fifteen percent had detectable HCV RNA (878/5960). Overall, 44% (n = 386/878) of people with current HCV initiated treatment within 6 months (13% online self-registration, 27% assisted registration in the community, 61% assisted registration in prison). Testing in prison compared with the community (adjusted odds ratio [aOR], 4.28; 95% CI, 3.04-6.03) was associated with increased odds of treatment initiation. Being a woman compared with a man (aOR, 0.68; 95% CI, 0.47-0.97) was associated with reduced treatment initiation.

Conclusions

The NSW DBS Pilot demonstrates the feasibility of using DBS to promote HCV testing and treatment in community and prison settings.

Dried Blood Spots-A Platform for Therapeutic Drug Monitoring (TDM) and Drug/Disease Response Monitoring (DRM)

This review provides an overview on the current applications of dried blood spots (DBS) as matrices for therapeutic drug (TDM) and drug or disease response monitoring (DRM). Compared with conventional methods using plasma/serum, DBS offers several advantages, including minimally invasiveness, a small blood volume requirement, reduced biohazardous risk, and improved sample stability. Numerous assays utilising DBS for TDM have been reported in the literature over the past decade, covering a wide range of therapeutic drugs. Several factors can affect the accuracy and reliability of the DBS sampling method, including haematocrit (HCT), blood volume, sampling paper and chromatographic effects. It is crucial to evaluate the correlation between DBS concentrations and conventional plasma/serum concentrations, as the latter has traditionally been used for clinical decision. The feasibility of using DBS sampling method as an option for home-based TDM is also discussed. Furthermore, DBS has also been used as a matrix for monitoring the drug or disease responses (DRM) through various approaches such as genotyping, viral load measurement, assessment of inflammatory factors, and more recently, metabolic profiling. Although this research is still in the development stage, advancements in technology are expected to lead to the identification of surrogate biomarkers for drug treatment in DBS and a better understanding of the correlation between DBS drug levels and drug responses. This will make DBS a valuable matrix for TDM and DRM, facilitating the achievement of pharmacokinetic and pharmacodynamic correlations and enabling personalised therapy.

Impact of storage time in dried blood samples (DBS) and dried plasma samples (DPS) for point-of-care hepatitis C virus (HCV) RNA quantification and HCV core antigen detection

The scale-up of hepatitis C virus (HCV) diagnosis and treatment requires affordable and simple tools to improve access to care, especially in low- and middle-income settings with limited infrastructure or high-risk populations. Dried blood and plasma samples (DBS and DPS) are useful alternative for hepatitis C detection in settings lacking adequate infrastructure. We evaluated the performance of DBS and DPS vs plasma in a point-of-care HCV RNA quantitative assay (Xpert HCV Viral Load-Cepheid), and compared HCV core antigen (HCVcAg) detection by the Architect HCV core antigen assay (Abbott) in DBS vs serum. The dried samples were stored at room temperature for different storage times to reproduce the time from sampling to testing in settings with centralized diagnosis or when testing mobile populations. HCV RNA quantification in DBS and DPS presented 100% sensitivity and specificity and a high correlation for up to 3 months of storage. HCV viremia showed a mean decrease of 0.5 log10 IU/mL (DBS) and 0.3 log10 IU/mL (DPS) for storage times up to 1 month. Architect HCVcAg detection presented high sensitivity/specificity (96%/100%) in DBS tested immediately after sampling, decreasing to 86% sensitivity after 7 days of storage. However, sensitivity increased when an optimized cut-off was applied for each storage time. We conclude that DBS and DPS are suitable samples for HCV RNA detection and quantification, being DPS more reliable for shorter storage times. DBS can be also used for HCVcAg qualitative detection and the sensitivity can be increased when adjusting the cut-off values. IMPORTANCE Hepatitis C infection remains a global burden despite the effectiveness of antivirals. In the WHO roadmap to accomplish HCV elimination by 2030, HCV diagnosis is one of the main targets. However, identifying patients in resource-limited settings and high-risk populations with limited access to healthcare remains a challenge and requires innovative approaches that allow decentralized testing. The significance of our research is in verifying the good performance of dried samples for HCV diagnosis using two different diagnostics assays and considering the effect of room temperature storage in this sample format. We confirmed dried samples are an interesting alternative for HCV screening and reflex testing in resource-limited settings or high-risk populations.

A 'one-stop-shop' point-of-care hepatitis C RNA testing intervention to enhance treatment uptake in a reception prison: The PIVOT study

BACKGROUND & AIMS

Prisons are key venues for scaling-up hepatitis C virus (HCV) testing and treatment. Complex clinical pathways and frequent movements of people in prison remain barriers to HCV care. This study evaluated the impact of a 'one-stop-shop' point-of-care HCV RNA testing intervention on treatment uptake compared with standard of care among people recently incarcerated in Australia.

METHODS

PIVOT was a prospective, non-concurrent, controlled study comparing HCV treatment uptake during 'standard of care' (n = 239; November 2019-May 2020) and a 'one-stop-shop' intervention (n = 301; June 2020-April 2021) in one reception prison in Australia. The primary endpoint was uptake of direct-acting antiviral treatment at 12 weeks from enrolment. Secondary outcomes included the time taken from enrolment to each stage in the care cascade.

RESULTS

A total of 540 male participants were enrolled. Median age (29 vs. 28 years) and history of injecting drug use (48% vs. 42%) were similar between standard of care and intervention phases. Among people diagnosed with current HCV infection (n = 18/63 in the standard of care phase vs. n = 30/298 in the intervention phase), the proportion initiating direct-acting antiviral treatment within 12 weeks from enrolment in the intervention phase was higher (93% [95% CI 0.78-0.99] vs. 22% [95% CI 0.64-0.48]; p <0.001), and the median time to treatment initiation was shorter (6 days [IQR 5-7] vs. 99 days [IQR 57-127]; p <0.001) compared to standard of care.

CONCLUSIONS

The 'one-stop-shop' intervention enhanced treatment uptake and reduced time to treatment initiation among people recently incarcerated in Australia, thereby overcoming key barriers to treatment scale-up in the prison sector.

IMPACT AND IMPLICATIONS

This study provides important insights for policymakers regarding optimal HCV testing and treatment pathways for people newly incarcerated in prisons. The findings will improve health outcomes in people in prison with chronic HCV infection by increasing testing and treatment, thereby reducing infections, liver-related morbidity/mortality, and comorbidities. The findings will change clinical practice, clinical guidelines, and international guidance, and will inform future research and national and regional strategies, in particular regarding point-of-care testing, which is being rapidly scaled-up in various settings globally. The economic impact will likely include health budget savings resulting from reduced negative health outcomes relating to HCV, and health system efficiencies resulting from the introduction of simplified models of care.

CLINICAL TRIALS REGISTRATION

This study is registered at Clinicaltrials.gov (NCT04809246).

Optimizing point-of-care testing strategies for diagnosis and treatment of hepatitis C virus infection in Australia: a model-based cost-effectiveness analysis

Background

Timely diagnosis and treatment of hepatitis C virus (HCV) is critical to achieve elimination goals. This study evaluated the cost-effectiveness of point-of-care testing strategies for HCV compared to laboratory-based testing in standard-of-care.

Methods

Cost-effectiveness analyses were undertaken from the perspective of Australian Governments as funders by modelling point-of-care testing strategies compared to standard-of-care in needle and syringe programs, drug treatment clinics, and prisons. Point-of-care testing strategies included immediate point-of-care HCV RNA testing and combined point-of-care HCV antibody and reflex RNA testing for HCV antibody positive people (with and without consideration of previous treatment). Sensitivity analyses were performed to investigate the cost per treatment initiation with different testing strategies at different HCV antibody prevalence levels.

Findings

The average costs per HCV treatment initiation by point-of-care testing, from A$890 to A$1406, were up to 35% lower compared to standard-of-care ranging from A$1248 to A$1632 depending on settings. The average costs per treatment initiation by point-of-care testing for three settings ranged from A$1080 to A$1406 for RNA, A$960-A$1310 for combined antibody/RNA without treatment history consideration, and A$890-A$1189 for combined antibody/RNA with treatment history consideration. When HCV antibody prevalence was <74%, combined point-of-care HCV antibody and point-of-care RNA testing were the most cost-effective strategies. Modest increases in treatment uptake by 8%-31% were required for immediate point-of-care HCV RNA testing to achieve equivalent cost per treatment initiation compared to standard-of-care.

Interpretation

Point-of-care testing is more cost-effective than standard of care for populations at risk of HCV. Testing strategies combining point-of-care HCV antibody and RNA testing are likely to be cost-effective in most settings.

Funding

National Health and Medical Research Council.

Barriers and enablers to testing for hepatitis C virus infection in people who inject drugs - a scoping review of the qualitative evidence

BACKGROUND

Injection drug use is the primary mode of transmission of hepatitis C virus (HCV) infection in the developed world and guidelines recommend screening individuals with current or history of injection drug use for HCV; however, the majority of those living with HCV in Canada are not aware of their positive status. This low level of HCV status awareness suggests that screening is not effective with current testing strategies. The aim of this review is to determine what barriers and enablers people who inject drugs (PWID) experience surrounding testing for HCV to help inform the development of an engaging testing strategy.

METHODS

Comprehensive literature searches were conducted using Medline, Embase and CINAHL in February 2021. Included studies investigated the barriers and enablers to testing for HCV in PWID and the experiences of PWID in testing for HCV. Studies were included if they were qualitative or mixed-methods design, involved people with current injection drug use or those with a history of injecting drugs, and were written in the English language. Studies were compared and common themes were coded and analyzed.

RESULTS

The literature search resulted in 1554 citations and ultimately nine studies were included. Common barriers included self-perception of low risk for HCV, fear of diagnosis, stigma associated with IV drug use and HCV, antipathy in relation to mainstream health care services, limited knowledge about HCV, lack of rapport with provider, lack of motivation or competing priority of drug use, and limited awareness of new treatment options. Common enablers to testing included increasing awareness of HCV testing and treatment and providing positive narratives around HCV care, positive rapport with provider, accessible testing options and individualized care.

CONCLUSION

While there has been some qualitative research on barriers and enablers to testing for HCV in PWID more research is needed to focus on this research question as a primary objective in order to provide more understanding from the participant's perspective.

Emerging Microfluidic Devices for Sample Preparation of Undiluted Whole Blood to Enable the Detection of Biomarkers

Blood testing allows for diagnosis and monitoring of numerous conditions and illnesses; it forms an essential pillar of the health industry that continues to grow in market value. Due to the complex physical and biological nature of blood, samples must be carefully collected and prepared to obtain accurate and reliable analysis results with minimal background signal. Examples of common sample preparation steps include dilutions, plasma separation, cell lysis, and nucleic acid extraction and isolation, which are time-consuming and can introduce risks of sample cross-contamination or pathogen exposure to laboratory staff. Moreover, the reagents and equipment needed can be costly and difficult to obtain in point-of-care or resource-limited settings. Microfluidic devices can perform sample preparation steps in a simpler, faster, and more affordable manner. Devices can be carried to areas that are difficult to access or that do not have the resources necessary. Although many microfluidic devices have been developed in the last 5 years, few were designed for the use of undiluted whole blood as a starting point, which eliminates the need for blood dilution and minimizes blood sample preparation. This review will first provide a short summary on blood properties and blood samples typically used for analysis, before delving into innovative advances in microfluidic devices over the last 5 years that address the hurdles of blood sample preparation. The devices will be categorized by application and the type of blood sample used. The final section focuses on devices for the detection of intracellular nucleic acids, because these require more extensive sample preparation steps, and the challenges involved in adapting this technology and potential improvements are discussed.

Evaluation of Simplified HCV Diagnostics in HIV/HCV Co-Infected Patients in Myanmar

To evaluate a decentralised testing model and simplified treatment protocol of hepatitis C virus (HCV) infection to facilitate treatment scale-up in Myanmar, this prospective, observational study recruited HIV-HCV co-infected outpatients receiving sofosbuvir/daclatasvir in Yangon, Myanmar. The study examined the outcomes and factors associated with a sustained virological response (SVR). A decentralised "hub-and-spoke" testing model was evaluated where fingerstick capillary specimens were transported by taxi and processed centrally. The performance of the Xpert HCV VL Fingerstick Assay in detecting HCV RNA was compared to the local standard of care ( plasma HCV RNA collected by venepuncture). Between January 2019 and February 2020, 162 HCV RNA-positive individuals were identified; 154/162 (95%) initiated treatment, and 128/154 (84%) returned for their SVR12 visit. A SVR was achieved in 119/154 (77%) participants in the intent-to-treat population and 119/128 (93%) participants in the modified-intent-to-treat population. Individuals receiving an antiretroviral therapy were more likely to achieve a SVR (with an odds ratio (OR) of 7.16, 95% CI 1.03-49.50), while those with cirrhosis were less likely (OR: 0.26, 95% CI 0.07-0.88). The sensitivity of the Xpert HCV VL Fingerstick Assay was 99.4% (95% CI 96.7-100.0), and the specificity was 99.2% (95% CI 95.9-99.9). A simplified treatment protocol using a hub-and-spoke testing model of fingerstick capillary specimens can achieve an SVR rate in LMIC comparable to well-resourced high-income settings.

Recommendations for the integral diagnosis of chronic viral hepatitis in a single analytical extraction

The Spanish Society of Digestive Pathology (SEPD), the Spanish Association for the Study of the Liver (AEEH), the Spanish Society of Infections and Clinical Microbiology (SEIMC) and its Viral Hepatitis Study Group (GEHEP), and with the endorsement of the Alliance for the Elimination of Viral Hepatitis in Spain (AEHVE), have agreed on a document to carry out a comprehensive diagnosis of viral hepatitis (B, C and D), from a single blood sample; that is, a comprehensive diagnosis, in the hospital and/or at the point of care of the patient. We propose an algorithm, so that the positive result in a viral hepatitis serology (B, C and D), as well as human immunodeficiency virus (HIV), would trigger the analysis of the rest of the virus, including the viral load when necessary, in the same blood draw. In addition, we make two additional recommendations. First, the need to rule out a previous hepatitis A virus (VHA) infection, to proceed with its vaccination in cases where IgG-type studies against this virus are negative and the vaccine is indicated. Second, the determination of the HIV serology. Finally, in case of a positive result for any of the viruses analyzed, there must be an automated alerts and initiate epidemiological monitoring.

Usefulness of dried blood spot samples for monitoring hepatitis C treatment outcome and reinfection among people who inject drugs in a test-and-treat program

Dried blood spots (DBS) are a reliable tool to diagnose viremic hepatitis C virus (HCV) infection. We evaluated the clinical performance of a DBS-based molecular assay for the assessment of cure and reinfection after on-site treatment at a harm reduction center (HRC). Genotyping from DBS samples was also assessed to discriminate reinfection from treatment failure. People who inject drugs (PWID) from an ongoing test-and-treat pilot at the largest HRC in Barcelona were included in the study. HCV-RNA detection from DBS collected after treatment (with follow-up at 12, 36, and 60 weeks) was compared with a molecular point-of-care test using finger-stick blood (GeneXpert). Baseline and follow-up DBS samples were genotyped by NS5B sequencing or commercial real-time PCR. Among treated patients, 193 follow-up DBS samples were tested. The DBS-based assay showed 100% specificity (129/129), and sensitivity ranged from 84.4% to 96.1% according to different viral load cut-offs (from detectable to 3000 IU/mL). Sensitivity as test of cure (follow-up 12) ranged from 85.1% to 97.4%. Among the 64 patients with recurrent viremia, 10.9% had low viral loads (≤1000 IU/mL); HCV genotyping allowed us to classify 73.5% of viremic cases either as reinfection or as treatment failure. DBS samples are useful to assess cure and differentiate reinfection from relapse after HCV antiviral treatment in the real world, facilitating decentralization of treatment and posttreatment follow-up in PWID. However, a fraction of patients presented with low viral loads, limiting viremia detection and genotyping in DBS and, therefore, repeat testing is recommended.

Effect of the Hematocrit and Storage Temperature of Dried Blood Samples in the Serological Study of Mumps, Measles and Rubella

Dried blood spots (DBSs) are an economical and convenient alternative to serum/plasma, which allow for the serological and molecular study of different pathogens. Sixty-four blood samples were collected by venipuncture and spotted onto Whatman™ 903 cards to evaluate the utility of DBSs and the effect of the storage temperature for 120 days after sample collection to carry out serological diagnosis. Mumps, measles and rubella IgG were investigated from DBSs and plasma using an automated chemiluminescent immunoassay. Using a calculated optimal cut-off value, the serological evaluation of mumps, measles and rubella using DBSs achieved high sensitivity (100%, 100% and 82.5%, respectively) and specificity (100%, 87.5% and 100%, respectively). The correlation observed between the plasma and the DBSs processed after sample collection was high (0.914-0.953) for all antibodies studied, both considering hematocrit before sample elution or not. For the different storage conditions, the correlation with plasma was high at 4 °C (0.889-0.925) and at -20 °C (0.878-0.951) but lower at room temperature (0.762-0.872). Measles IgG results were more affected than other markers when DBSs were stored at any temperature for 120 days. To summarize, hematocrit does not affect the processing of DBSs in the study of serological markers of mumps, measles and rubella. DBS stability for serological diagnosis of mumps and rubella is adequate when samples are stored at -20 °C or 4 °C, but not at room temperature, for a period of 4 months.

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.

RT-LAMP-Based Molecular Diagnostic Set-Up for Rapid Hepatitis C Virus Testing

Hepatitis C virus (HCV) infections occur in approximately 3% of the world population. The development of an enhanced and extensive-scale screening is required to accomplish the World Health Organization's (WHO) goal of eliminating HCV as a public health problem by 2030. However, standard testing methods are time-consuming, expensive, and challenging to deploy in remote and underdeveloped areas. Therefore, a cost-effective, rapid, and accurate point-of-care (POC) diagnostic test is needed to properly manage the disease and reduce the economic burden caused by high case numbers. Herein, we present a fully automated reverse-transcription loop-mediated isothermal amplification (RT-LAMP)-based molecular diagnostic set-up for rapid HCV detection. The set-up consists of an automated disposable microfluidic chip, a small surface heater, and a reusable magnetic actuation platform. The microfluidic chip contains multiple chambers in which the plasma sample is processed. The system utilizes SYBR green dye to detect the amplification product with the naked eye. The efficiency of the microfluidic chip was tested with human plasma samples spiked with HCV virions, and the limit of detection observed was 500 virions/mL within 45 min. The entire virus detection process was executed inside a uniquely designed, inexpensive, disposable, and self-driven microfluidic chip with high sensitivity and specificity.