Update on the Replacement of the HCV RNA International Standard

1
Update on the Replacement of the HCV RNA
International Standard

• Sally Baylis Alan Heath, NIBSC
• SoGAT XX, Warsaw 12-13 June 2007

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Replacement of the 2nd International Standard for
HCV RNA (96/798)

• Proposal made at SoGAT 2005 to replace the HCV
  RNA International Standard as requested by WHO
• Agreement that HCV 1a genotype would be sourced
  would be anti-HCV negative and diluted in plasma
  rather than cryosupernatant

3
Candidate Standards for Evaluation

• 3 anti-HCV negative window period genotype 1a
  donations have been obtained
• The genotype of each has been confirmed by LiPA
  DNA sequencing
• Absence of other viral markers confirmed in these
  stocks
• Material has been freeze-dried in two batches
• Batch 1 (NIBSC Code 06/100), 2085 vials, fill CV
  0.62
• Batch 2 (NIBSC code 06/102), 2100 vials, fill CV
  1.82

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Panel for Collaborative study

• Sample 1 2nd International Standard for HCV RNA
  (96/798)
• Sample 2 - new freeze-dried preparation 06/100
• Sample 3 - new freeze-dried preparation 06/102
• Sample 4 liquid/frozen bulk material (NIBSC
  code 06/118) that was used to prepare Samples 2
  3

5
Collaborative Study

• Collaborative study commenced in November 2006
• Participants requested to test samples in four
  independent assays
• 33 laboratories from 14 countries participated in
  the study
• 40 data sets received 25 from quantitative
  assays 15 from qualitative assays
• NIBSC collated analysed data

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Types of Quantitative Assays Used by Participants
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Types of Qualitative Assays Used by Participants
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Estimated IU/ml (log10) from Quantitative Assays
N - Number of laboratory estimates SD -
Standard Deviation of log10 estimates across
laboratories
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Estimated PCR Detectable Units/ml (log10) from
Qualitative Assays
N - Number of laboratory estimates SD -
Standard Deviation of log10 estimates across
laboratories
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Overall Mean Potencies (log10 IU/ml) Relative to
Sample 1
N - Number of laboratory estimates SD -
Standard Deviation of log10 estimates across
laboratories
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Accelerated Degradation Studies Sample 2

• Relative potencies of accelerated degradation
  samples with respect to Sample 2 stored at -20ºC
  (log10 drop), qPCR analysis
• Stability appears similar to 96/790 and 96/798
  studies on-going
• 96/798 from this study has not lost potency after
  gt10 years storage at -20 ºC

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Proposal for 3rd International Standard for HCV
RNA

• Real-time accelerated degradation data indicate
  that Sample 2 (06/100) is stable suitable for
  long term use
• Propose that 06/100 be established as the 3rd
  International Standard for HCV RNA with a unitage
  of 5.19 log10 IU/ml (4.89 log10 IU/vial)
• Report will be submitted to ECBS by July

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Acknowledgements

• Nita Shah David Padley NIBSC
• Professor Ewa Brojer, Institute of Hematology
  Blood
• Transfusion, Warsaw
• Dr Richard Smith, National Genetics Institute,
• Los Angeles
• Dr Vivienne James, HPA, Colindale
• Dr Michael Chudy, WHO, Geneva
• Collaborative study participants

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HCV RNA Collaborative Study Participants

• S Baylis, N Shah South Mimms, UK
• T Cuypers M Koppelman Amsterdam, The Netherlands
• C Defer Lille, France
• L Fanning Cork, Eire
• G Gesu Milan, Italy
• A Goglio Bergamo, Italy
• P Grant London, UK
• P Iudicone Rome, Italy
• L Jarvis, A Cleland Edinburgh, UK
• C Jork Springe, Germany
• S Kerby Bethesda, USA
• A Klotz, M Gessner Vienna, Austria
• R Madej Pleasanton, USA
• B Miller Karlsruhe, Germany
• S Mizusawa Tokyo, Japan
• C Negru Timisoara , Romania
• M Nübling Langen, Germany

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HCV RNA Collaborative Study Participants

• JM Pawlotsky Créteil, France
• M Pecorari Modena, Italy
• G Pisani Rome, Italy
• A Portela Moreira Madrid, Spain
• S Sauleda Barcelona, Spain
• H Schindl Vienna, Austria
• G Schneider Des Plaines, USA
• A da Silva Lisbon, Portugal
• R Smith Los Angeles, USA
• S Tassen Brentwood, UK
• P Taylor London, UK
• A van der Zanden Apeldoorn, The Netherlands
• YC Yang Taipei, Taiwan
• S Yerly Geneva, Switzerland
• M Zaccanelli Treviglio, Italy

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Update on the Stability of the HAV RNA
International Standard
Sally Baylis, Nita Shah Alan Heath, NIBSC SoGAT
XX, Warsaw 12-13 June 2007
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Background Hepatitis A Virus RNA IS

• The 1st International Standard for HAV RNA
  (00/560) and a second batch (00/562) were
  prepared in Q1, 2001
• 00/560 was evaluated in an international
  collaborative study, with data returned from 16
  laboratories
• The mean log10 equivalents/ml were 5.29 (00/560)
  and 5.07 (00/562)
• 1st International Standard (00/560) was
  established in 2003 with 50,000 IU/vial
• ECBS noted that 00/562 may be a replacement for
  00/560

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Stability Data 00/560 00/562

• Accelerated thermal degradation samples for
  00/560 and 00/562, stored at 4ºC for 6 years
  were tested in parallel with samples of 00/560
  stored at -20 ºC
• 00/560 a drop on 0.1 log10
• 00/562 a drop on 1.0 log10
• Conclude that 00/560 is highly stable

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Proposal to Replace the Parvovirus B19 DNA
International Standard
Sally Baylis, NIBSC SoGAT XX, Warsaw 12-13 June
2007
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Replacement of the Parvovirus B19 DNA IS 99/800

• The 1st International Standard for B19V DNA was
  established by the WHO ECBS in October 2000
• Estimated date of exhaustion of the IS will be
  2008/9 at current rate of usage
• Materials coded AA (99/800) BB (99/802) showed
  no significant difference in potency in the
  collaborative study
• ECBS noted that BB (made from the same stock as
  AA) could be reserved for potential future use as
  a replacement standard

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Candidate 2nd International Standard

• Materials coded AA (99/800) BB (99/802) showed
  no significant difference in potency in the
  original collaborative study
• ECBS noted that BB (prepared from the same stock
  as AA) could be reserved for potential future use
  as a replacement standard
• Current study designed to demonstrate the
  equivalence of the candidate replacement (BB) to
  AA
• Real-time data on samples AA BB
• Accelerated degradation data for samples AA BB