All you can use to diagnose HCV 4 th Annual Preceptorship EMERGING CHALLENGES IN THE MANAGEMENT OF CHRONIC LIVER DISEASE Berne 18 th May 2017

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1 All you can use to diagnose HCV 4 th Annual Preceptorship EMERGING CHALLENGES IN THE MANAGEMENT OF CHRONIC LIVER DISEASE Berne 18 th May 2017 Francesco Negro University Hospital of Geneva, Switzerland

2 OR, HOW TO DIAGNOSE HCV BEFORE HCV

3

4 me The Far Side by Gary Larson

5 "Steatosis is frequent in post-transfusion hepatitis"

6 Science 1989;244:359-62

7 The Hepatitis C Virus Major cause of parenterally-transmitted NANB hepatitis Member of the Hepacivirus genus, Flaviviridae family (e.g. yellow fever virus, Dengue, West Nile encephalitis...) Enveloped virion Single-stranded, (+) polarity RNA genome, ~9,600 nt RNA polymerase lacks proof-reading activity: Elevated, three-tiered heterogeneity (7 genotypes, 67 subtypes, quasispecies at the individual level) Selection of drug resistant variants Hurdle to vaccine development

8 HCV RNA genome and polyprotein TROELS et al, Nat Med 2013;19:837-49

9 Diagnosis of viral infections Detection of specific pathological features Direct detection of the virus: Genome Structural components In vitro or in vivo infectivity assays Detection of specific immune response(s)

10 ALT The diagnosis of HCV infection requires two markers Self-limited acute hepatitis C Acute hepatitis C progressing to chronicity Symptoms ± HCV RNA Anti-HCV Months after exposure Months // Years

11 Anti-HCV Indicates exposure to HCV Present throughout acute, resolved and chronic infection Laboratory assays: EIAs, CIA (chemiluminescence-based), MEIA (microparticles) Serum, plasma, dried blood spot Confirmatory Immunoblot assays Serum, plasma Point of care (POC) assays / Rapid diagnostic tests (RDTs) Whole blood, serum, plasma, oral fluid (immunochromatographic)

12 First generation anti-hcv test (EIA-1) C E1 E2 p7 NS2 NS3 NS4A NS4B NS5A NS5B c100-3 Sensitivity in high-prevalence setting: ~70-80% Specificity in low-prevalence blood donor setting: ~30-50% Window period to seroconversion: ~150 days

13 Second generation anti-hcv test (EIA-2) C E1 E2 p7 NS2 NS3 NS4A NS4B NS5A NS5B c22 33c c100-3 Sensitivity in high-prevalence setting: ~92-95% Specificity in low-prevalence blood donor setting: ~50-60% Window period to seroconversion: ~80 days

14 Third generation anti-hcv test (EIA-3) C E1 E2 p7 NS2 NS3 NS4A NS4B NS5A NS5B c22(p) c200 NS5 Sensitivity in high-prevalence setting: ~99.9% Specificity in low-prevalence blood donor setting: ~75% Window period to seroconversion: ~70 days

15 Anti-HCV seroreversion is rare, but possible Study Setting Incidence (%) Mean FU (y) KONDILI et al, 2002 Central Italy, general population 7/36 (19.4) 7 LEFRERE et al, 2004 Paris area, untreated HIV- polytransfused 1/16 (6) 13.8 TASI et al, 2011 Taiwan, general population 17/386 (4.4) 7 KEE et al, 2012 Taiwan, SVR 2/166 (1.6) 4.7 Mostly occurring after spontaneous or therapy-induced viral clearance Rarely seen despite persistent HCV replication (HIV+) Implications: blood transfusion setting, seroprevalence studies

16 Markers of active HCV infection HCV RNA, detectable in serum/plasma ~1 week after exposure RT-PCR; bdna; TMA Real-time PCRs Broad dynamic range; LOD 15 IU/mL of HCV RNA WHO International HCV RNA standard - IU High specificities of up to 99% across all genotypes HCV genotyping Direct sequencing Restriction length polymorphism analysis Reverse hybridization Next-generation sequencing RAS detection and characterization HCV Core Antigen, detectable ~1-2 weeks after exposure

17 Nucleic Acid Technologies: the Challenges Requires expert technical staff Expensive equipment and reagents Dedicated procedure areas Requires pristine serum/plasma samples Not routinely performed in many clinical laboratories

18 HCV Core Antigen Detectable within 1-2 weeks after exposure to HCV Broad linear range of detection by serologic assays Test samples Serum, plasma, dried blood spots Lower sample volume than NAT No pristine sample needed Undetectable when HCV RNA <2000 IU/ml Requires Abbott ARCHITECT platform

19 Relationship Between HCV Core Ag and HCV RNA Levels Analytical sensitivity corresponding to ~ IU/mL of HCV RNA Rare false-negatives (core Ag-negative, HCV RNA-positive) CHEVALIEZ et al, J Clin Virol 2014;61:145-8 Preseroconversion panel: 100% sensitivity Post-seroconversion sesitivity 94.3% MIXSON-HAYDEN et al, J Clin Virol 2015;66:15-8 Recommended by EASL!

20 The anti-hcv-negative window phase (i.e. preceding seroconversion) HCV RNA Anti-HCV HCV core Ag Days after exposure To be considered in high-risk settings (IVDU, HIV+ MSM), immunocompromised individuals, hemodialysis

21 CDC s Updated HCV Testing Guidelines - + Recently exposed Immunocompromised Other special medical circumstances Not detected - HCV RNA Current Past/Resolved False-positive + Detected Never infected Susceptible Past/Resolved infection False positive anti-hcv Current HCV infection Exposure within prior 6 months Additional follow-up needed Testing for HCV infection: An update of guidance for clinicians and laboratorians. MMWR 2013;62(18)

22 The 7 HCV Genotypes Direct sequencing Restriction length polymorphism analysis Reverse hybridization Next-generation sequencing Tier Nucleotide identity Genotypes 66-69% 7 Subtypes 77-89% 67 Quasispecies 91-99% N BUKH J. J Hepatol 2016;65(suppl ):S2-S21

23 HCV gene sequencing as a tool for precise genotyping in the era of DAA CECCHERINI-SILBERSTEIN et al, Hepatology 2016;63:1058-9

24 HCV outbreak (n=6) in patients receiving propofol from the same anesthesiologist using a single-patient-use vial of propofol for multiple patients GUTELIUS et al, Gastroenterology 2012;139:163-70

25 Phylogenetic consensus tree of HCV E1-HVR1 sequences identified from selected NHANES-III participants and outbreak patients GUTELIUS et al, Gastroenterology 2012;139:163-70

26 YERLY et al, J Infect Dis 2001;184:369-72

27 HCV Resistance Associated Substitutions (RAS) Testing Prior to First-line Therapy Systematic testing for HCV resistance prior to treatment is NOT recommended. Indeed, this obligation would seriously limit access to care. Treatment can be optimized without this information Physicians who have easy access to a reliable test assessing HCV resistance to NS5A inhibitors (spanning amino acids 24 to 93) can use these results to guide their decisions The test should be based on population sequencing (reporting RAS as present or absent ) or deep sequencing with a cutoff of 15% (only RAS that are present in more than 15% of the sequences generated must be considered) EASL Recommendations on Treatment of Hepatitis C J Hepatol 2017;66:153-94

28 HCV Resistance Testing Prior to First-Line DAA Therapy Not available Available, reliable, interpretable, understandable* *recommended for GZR/EBR for US patients with GT1a Optimize therapy to avoid treatment failure Presence of NS5As RASs conferring highlevel resistance (pop seq or >15%) SOF/LDV, SOF/DCV, SOF/SIM: add RBV in G1a TE SOF/VEL: add RBV in G3 TE patients and cirrhotics Add ribavirin and/or increase treatment duration in patients with NS5A RAS GZR/EBR: use 16 weeks with RBV in GT1a EASL Recommendations on Treatment of Hepatitis C J Hepatol 2017;66:153-94

29 Global prevalence of viremic HCV (reported and extrapolated) Of the 80 million persons with chronic HCV infection, 70% live in low- and middle-income countries (LMIC) GOWER et al, J Hepatol 2014;61(suppl 1):S45-S57

30 Inadequate testing is a major barrier to adequate management In LMIC, <5% patients are estimated to be aware of their HCV infection: Lack of provider and patient awareness Poor accessibility of testing sites Inadequate resources for HCV testing services and commodities Concerns about stigma and discrimination Diagnosis of HCV is a two-step procedure (antibody screening, followed by confirmation of active infection by HCV RNA testing), affecting retention in care

31 The ideal, simplified management Should not require hospital facilities and/or trained personnel Should not require refrigeration of samples and/or reagents Should not require electricity Should be one-step to ensure retention in care Should not miss subgroups with clinically significant complications (cirrhosis, HCC, extrahepatic manifestations)

32 First WHO prequalified RDT for anti-hcv SD BIOLINE HCV TM, POC test by Standard Diagnostics, Inc. (South Korea) Available also for HIV-1 and -2, syphilis, Dengue fever, malaria. Performed by health workers with limited training

33 Rapid Diagnostic Test: the OraQuick TM Simple, non-instrumented, rapid (20 min), point-of-care test developed by OraSure Technologies Inc. (Bethlehem, PA, USA) Can be used on serum, whole venous blood, fingerstick blood or crevicular fluid Sensitivity is % (saliva), 100% (serum), specificity is 100% LEE et al, J Virol Methods. 2011;172:27 31; CHA et al, Ann Lab Med 2013;33:184-9 Licensed by FDA for use on whole blood (2010) or fingerstick blood (2011) WHO prequalified + -

34 Performance of HCV RDTs Result Orasure Hexagon CTK Cypress Abon True pos False pos True neg False neg Specificity 100% 98% 94% 93% 88% Sensitivity 100% 99% 100% 97% 100% N = 270 Kamili S, personal communication

35 Seronegative (n=170), cleared (n=26), and HCV RNA+ (n=315) Whole blood spotted on a filter paper Dried and stored at -80 C or at room temperature for 19 ± 1 months A 6-mm disk was punched and processed for anti-hcv, HCV Core Ag, HCV RNA and HCV genotyping What about Dried Blood Tests? To increase specificity, anti-hcv threshold should be modified HCV RNA levels are still underestimated HCV RNA is stable for more than 1 year at RM HCV Core Ag determination cannot replace viremia SOULIER et al, J Infect Dis 2016;213:

36 Where are we going?

37 JUPITER AND BEYOND

38 The «democratization» of medicine

39 Healthcare provider-assisted diagnosis Self-Diagnosis???

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43 Computers are getting faster. Also, computers are getting faster faster that is, the rate at which they're getting faster is increasing (Feb. 10, 2011)

44 credit: nbcnews.com

45 Percent of adults who report owning a smartphone 1 In Q4 2016, there were 7.5 billion smartphone subscriptions 2 1 Spring 2015 Global attitudes Survey. Q71 & Q72. Pew Research Center 2 Cerwall, P. & Report, E. M. Ericssons mobility report

46 Antibody assay: HIV, syphilis 2 ml of blood by fingerprick Sensitivity 92% Specificity % 15 minutes 1.6 mw per test Audio jack powered 1.4 USD per triplex

47 Loop-mediated isothermal amplification for HIV RNA NO thermal cycling 95% sensitivity if HIV RNA >1000 copies/ml 100% specificity 12 samples per chip 30 min reaction Powered by USB port Scientific Reports 2016;6:36000

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50 Diagnosis in the future: Deep convolutional neural networks Outfitted with deep neural networks, mobile devices can potentially extend the reach of dermatologists outside of the clinic. [...] Smartphones may provide low-cost universal access to vital diagnostic care ESTEVA et al, Nature 2017 (in press)

51 Diagnosis of HCV in the future Ideally, one-step, at point-of-care/home Technological advances will change dramatically the way we deliver care (and teach medicine) Patients will generate and own many of their personal health data (sensors, home diagnostic tools...) Interaction with care providers may evolve towards virtual visits Diagnoses will rely upon AI

52 Are you afraid of technology?

53 «Like tears in rain»