HCV Diagnostics Technology Landscape
AIDS 2014, 10th International AIDS Conference21 July 2014
Maurine M. MurtaghUNITAID Consultant
Current HCV Testing Continuum
ILLUSTRATIVE
With available HCV treatment, the testing cascade for HCV is complex and expensive, which means that it is very challenging for resource-limited settings.
With the potential availability of DAAs, a simplified HCV testing algorithm should be possible, which will help make HCV diagnosis and monitoring attainable in resource-limited settings.
SerodiagnosisRDT
HCV RNA or Ag
Line Probe
RT PCR
BiopsyBio-Marker
HCV RNA
Need f
or
Serv
ice
Screening
ConfirmatoryTest
Treatment Monitoring
Genotyping FibrosisStaging
PrognosticMarkers
IL-28B
Potential HCV Testing Continuum - DAAs
ILLUSTRATIVE
Screening and confirmatory testing will still be needed, although these might be combined into a single qualitative assay to detect the presence of HCV RNA or Ag.
Fibrosis staging may be needed, although perhaps not for HIV co-infected patients, and testing HCV clearance/cure at the end of treatment and post-treatment, will also be required. But, qualitative HCV RNA or Ag technologies used for confirmation/diagnosis of HCV could also be used for clearance/cure testing.
SerodiagnosisRDT
HCV RNA or Ag
Need f
or
Serv
ice
Screening
ConfirmatoryTest
Test of Cure
FibrosisStaging
Bio-markerTE
HCV RNA or Ag
Pipeline Technologies – Confirmation/Cure
With all-oral HCV regimens expected in ~2016, it is anticipated that baseline quantification of HCV may not be necessary. It is also anticipated that with shorter and more effective regimens, quantitative HCV RNA testing for treatment monitoring can be eliminated.
It would then be possible to use a highly sensitive qualitative HCV RNA assay or HCV Ag assay to confirm the presence of the virus (for diagnosis) and to use the same assay again at the end of treatment and at a defined point post-treatment to confirm cure.
Existing Technologies – Confirmation/Efficacy/Cure
Assays include those from Roche (COBAS®), Abbott (m2000), Siemens (VERSANT®), and others.These pose access challenges similar to those for HIV viral load testing. Solutions include the use of DBS for HCV viral load testing as well as the introduction of platforms that can be used nearer to the point of patient care.
Currently, both qualitative HCV testing for confirmation of HCV diagnosis and quantitative HCV viral load testing for monitoring treatment efficacy and clearance and is done on sophisticated platforms requiring highly trained personnel in central laboratory settings.
Some Potential HCV RNA and HCV Ag Products
Low-Resourced Lab (minimal to no sample prep) Point-of-Care
Wave 80 EOSCAPE™
IQuumLiat™
Analyzer
Cepheid GeneXpert® Quantitative
MolbioTruenat
HCT
Alere q Daktari HCV Quantitative
Viral LoadAssay Type PCR NAT bDNA-
based NATPortable,
~8lbs
PCR NAT RT PCR PCR NATPortable,
<11lbs
HCV Core Antigen,
Portable, 5.5lbs
Pan-genotypic
Yes Unknown Yes Yes Unknown Unknown
Time to Result
70 min 30-35 min ~95 min ~60 30-60 min 30 min
Battery Life 8 hours Unknown AC Power 8 hours 8 hours Up to 3 days
Device Cost <$10,000 ~$25,000 $17,000 $8,000 TBD $5,000
Cost/ Test <$20 TBD $10 - $17 $15 TBD $8
Market Launch for HCV
Not known Not known Ex-US launch early 2015
Not known Not known Late 2015
(Medium) (Low)
COMPLEXITY
Conclusions/Questions
More and better RDTs for screening HCV are needed, including RDTs that can reliably detect HCV in HIV co-infected patients.
More studies are needed to demonstrate that HCV Ag assays that detect HCV core antigen are sufficiently sensitive for use in diagnosis and testing for HCV clearance/cure.
While there is a reasonable pipeline of HCV viral load assays for use on platforms at the point of care in resource-limited settings, most developers are aiming for fully-quantitative assays. Is this what is really required in light of the advent of all-oral HCV treatment regimens?
Conclusions/Questions
In general, developers need guidance from stakeholders with respect to the key market requirements for HCV screening/diagnosis as well as monitoring, if any, and/or clearance/cure testing for HCV. Stakeholder-vetted TPPs could be helpful in this respect.
If the cost of DAAs can be brought down to levels where all-oral treatments for HCV are obtainable in resource-limited settings, the required diagnostic technologies need to be ready and appropriate for implementation.
Like HIV, this testing landscape is likely to include both lab-based platforms and diagnostics for use at or near the point of patient care.