Update on the development of clinical diagnostic run controls at NIBSC. Neil Almond Division of Virology

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1 Update on the development of clinical diagnostic run controls at NIBSC Neil Almond Division of Virology

2 BACKGROUND Molecular techniques are increasingly being used for microbiological diagnoses Assays being used comprise a mixture of inhouse developed assays and commercial kits How can we be sure that all assays are of appropriate and similar Accuracy Sensitivity

3 Reference Materials improved the Quality of NAT for Blood Viruses In 1990 s NIBSC worked with NBS s to develop in-run controls for blood-borne Viruses Working reagents underpinned by International Standards for NAT HCV, HIV-1, HIV-2 The availability of IS and Working Reagents improved the quality and accuracy for quantification of NAT assays 1 st Int l Standard for HIV-1 RNA 3 rd Int l Standard for HIV-1 RNA

4 Programme for Clinical Virology Joint activity of UK CVN /NIBSC /HPA started 2008 Prepare and supply materials to improve quality and comparability of NAT based diagnostic assays Whole organisms to be used as extraction reference control Supplied in buffer (10mM Tris/HCl; 2% FCS; ph7.4) Low organism copy number (PCR Ct 30; 10 3 fold above LOD) 22 monoplex working reagents available Ready for single use application CE marked (ISO accredited) Compliant with In Vitro Diagnostic Directive Opportunity to return data on-line through a Results Reporting System (RRS)

5 NIBSC CVN Group monoplexes available Influenza A H1N1 07/296 Influenza A H3N2 07/298 Influenza B 07/300 Norovirus G I 08/318 Norovirus G II - 07/294 HSV type I 08/224 HSV type II 08/226 Hu CMV 08/314 EBV 08/316 Coxsackievirus B 08/174 Adenovirus 08/114 Parainfluenza type 1-08/176 Parainfluenza type 2-08/178 Parainfluenza type 3-08/118 Parainfluenza type 4-08/180 RSV 08/120 Hu Rhinovirus 08/324 Hu Metapneumovirus 08/320 Parechovirus 08/322 VZV 08/310 Rotavirus 09/106 Coronavirus 229E 09/132

6 What have these monoplexes told us - Norovirus GII

7 What have these monoplexes told us - Norovirus GII Some assays don t detect this sample

8 What have these monoplexes told us - Norovirus GII Intra laboratory reproducibility varies between labs

9 What have these monoplexes told us - Norovirus GII Labs with excellent reproducibility give different answers are either correct?

10 Feedback from CVN Customers Request for Multiplex reagents cost and convenience Syndromic? respiratory e.g. flu (A H1, A H3 & B), metapneumo, RSV, rhino, paraflu (1-4), corona gastric e.g. noro (GI & GII), adeno 41, astro, rota, sapo Target? DNA RNA e.g. Cox B4, parecho, boca All-in-one? Produced 11/ Candidate All in one solution Contains 25 components in usual buffer Each component designed to provide signal at 30 Ct Shipped to 29 labs in CVN for evaluation Jan 13

11 Composition of 11/ Flu A H1N1 Flu A H3N2 Parainfluenza 1,2,3,4 RSV A Hu Metapneumovirus Rhinovirus Coronavirus229E Parechovirus Enterovirus Norovirus Type I Norovirus Type II Sapovirus Rotavirus Astrovirus Adenovirus 2 Adenovirus 41 Herpes Simplex 1 Herpes Simplex 2 Varicella Zoster Epstein Barr Cytomegalovirus Supplied as frozen (-70C) in 1ml aliquots

12 Results from Multiplex so far Issues identified using monoplexes still present. Some labs fail to detect specific pathogens Ad41 (40%); Hu Meta (80%); Sapo (83%) High range in apparent sensitivity of some assays Noro GII: results Ct(5000 fold range?) Variable results in viral load where it determines treatment CMV results Ct (100 fold range?) Data from participants will contribute to CE marking dossier.

13 Conclusions Reference materials improve the quality of molecular diagnostic assays every assay needs controls External in run controls along with a Results Reporting System are supporting UK CVN to share and compare data and good practice without being prescriptive Establish suitability of assays and modifications Assess Intra-lab reproducibility Determine Inter-lab variability Provide framework for unified system of quantification CVN/NIBSC are working to provide the tools to ensure excellence in Clinical Microbiology

14 Future Activities Seek ISO13485 accreditation for multiplex diagnostic reference materials Investigate ways of improving Stability of multiplex reference Shipping of multiplex reference Establish more robust methods of quantification Link to IS where available Encourage application of relative potency

15 Acknowledgement CVN Mark Zuckerman Bill Carmen Maggie Hopper All participants in evaluation and questionnaire NIBSC Phil Minor Rob Anderson Sophie Collot-Teixeira Heather Carre Anna Gottlieb Jacqueline Fryer Kathryn Doris