Life. Made better. West Nile Virus: How to address the „virus d‘jour“ Thomas R.Kreil,Ph.D. Global Pathogen Safety, Director Æ on behalf ofthe PPTA „Viral Safety W orking Group“ West Nile Virus,W N V • History (1) – 1937:Isolated from the blood of afebrilewoman, West Nile district of Uganda – 1957:Recognized as the cause of severe meningoencephalitis in elderly patients during an outbreak in Israel – 1996:First outbreak in Europe, approx. 450 casesin Romenia – 1999:First detection inthe United States of America, approx. 60 cases on the East Coast – 2002:Epidemic of unprecedented size in the US West Nile Virus,W N V • History (2): 2002 US epidemic – 3873 human cases reported to CDC / Arbonet,including 246 human fatalities (CDC, Dec. 31, 2002) – Virus transmission through • Solid organ transplantation • Blood transfusion (M M W R [2002] 51(39): 879) • { Breast milk, possible (MMWR [2002] 51(39): 877-878) } – Laboratory acquired (2 cases: M M W R [2002] 51 (50):1133) West Nile Virus,W N V: transmission through solid organ transplants • CDC investigation West Nile Virus infection in organ donor and transplant recipients (MM W R [2002] 51: 790) – Four organ recipients from a single donor all developed clinical WNV infection – Donor`s pre-donation blood contained WN V West Nile Virus,W N V: transmission through blood products • Safety ofthe blood supply ? – (Labile) blood products for transfusion • Erythrocytes (red blood cells) • Thrombocytes • Fresh-frozen plasma (FFP) – (Stable) blood products (= plasma derivatives) West Nile Virus,W N V: transmission through labile blood products •„Estimated risk of WNV transimission through blood transfusion during an epidemicin Queens, New York City“ BJ Biggerstaff & LR Petersen, Transfusion [2002] 42: 1019 – <2.7 /10.000 risk oftransmission from a single unit (worst-case: generated during a recognized epidemic, assuming 100% transmission from viremic donor) – „...lack of data about blood transfusion-related flavivirus transmission ...“ Æ published before it ever happened !! West Nile Virus,W N V: transmission through labile blood products •„Investigations of WestNile Virus Infections in Recipientsof Blood Transfusions“ M M W R [2002] 51:973 – 6 out of 33 cases: evidence for transmission available, others still underinvestigation – Components identified: FFP, red blood cells West Nile Virus,W N V: the FDAs response • October 3,2002 Information about West Nile Virus and Blood Safety • October 25,2002: Guidance for Industry „Recom mendations for the Assessment of Donor Suitability and Blood and Blood Product Safety in Cases of Known or Suspected West Nile Virus Infection“ – Donor deferral – Retrieval, and quarantine West Nile Virus,W N V: the FDAs response • October 25,2002: Guidance for Industry Recommendations forthe Assessment ofDonor Suitability and Blood and Blood Product Safety in Cases of Known or Suspected West Nile Virus Infection „FDA has reviewed the viralreduction processes in place for all plasma derivatives. The methods in place have been validated to inactivate flaviviruses related to WN V.“ West Nile Virus,W N V: the FDAs response • FDA W orkshop on Development of Donor Screening Assays forWest Nile Virus, November 4 & 5, 2002 Goals and objectives 1) WNV pathogenicity and epidemiology in the U.S. 2) Methodologies suitable for screening of WN V in donors 3) Transmission to recipients ofblood, or human cells,tissues, and cellular ortissue based products (HCT/Ps) 4) WNV screening assays for future large-scale implementation 5) Issues relevanttothe implementation of WNV tests 6) FDA’s expectations for licensure ofW N V test 7) Strategies forinactivation of WNV West Nile Virus,W N V: FDA workshop, November 2002 • 3) Transmission to recipients of blood, or human cells, tissues, and cellular ortissue based products (HCT/Ps) – Solid organ transplantation – Blood transfusion Æ Donor deferral criteria (FD A guidance) West Nile Virus,W N V: FDA workshop, November 2002 • 7) Strategies forinactivation of WN V – (Labile) blood components fortransfusion – (Stable) plasma-derivatives West Nile Virus,W N V: FDA workshop, November 2002 • 7) Strategies forinactivation of WN V: (Labile) blood components for transfusion – Cerus: Psoralenes – Vitex: Inactines – Gambro: Riboflavine + light West Nile Virus,W N V: FDA workshop, November 2002 •Inactivation of WN V in (labile) blood components Preliminary Results Volume treated Initial Post treatment WNV Titer - Log - Comments Reduction WNV Titer Platelets Platelets RBC RBC (mL) (pfu/mL) 300 5.4 x 10 300 Platelets: RBC: 9.1 x 10 (pfu/mL) 5 5 <1 <1 (N=2) > 5.7 > 5.7 > 6.0 > 6.0 150 µM amotosalen and 3 J/cm2 UVA 200 µM S-303 No recoverable virus in 1 mL in 2 of 2 experiments No recoverable virus in 1 mL in 2 of 2 experiments West Nile Virus,W N V: FDA workshop, November 2002 • 7) Strategies forinactivation of WN V: (Stable) blood products,i.e.plasma-derivatives – Experience of the plasma proteins industry, based on the „model virus concept“ • CPMP guidance: CP M P/B WP/268/95 „...any virus used in a validation study is actually a model virus.“ – Verification (N OT: validation)studies West Nile Virus,and relatives –Flaviviridae,Flavivirus – West Nile Virus (W N V) » US 2002: 3873 clinical cases, 246 fatalities (CDC, Dec. 31, 2002) – St. Louis encephalitis virus (SLEV) » US 1975: 1800 clinical cases, 130 fatalities – Tick-borne encephalitis virus (TBEV) » Austria (8 mio.):up to 600 cases per year, 2% lethality – Flaviviridae,Pestivirus – Bovine viral diarrhea virus (BVDV) – Flaviviridae,Hepacivirus – Hepatitis C virus – Togaviridae,Alphavirus – Sindbisvirus (SIN V) West Nile Virus,and relatives: modelviruses Family [-viridae] Genus [-virus] HSA (3.5% - 25%) pasteurization HSA (5% - 25%) pasteurization F VIII solvent-detergent ivIg solvent-detergent FEIBA vapor heating HCV FlaviHepaci(>5.0 *) (>5.0 *) - BVDV FlaviPesti>6.2 / >6.1 >6.8 / >4.9 >5.2 >4.9 >5.1 * B Horowitz & E Ben-Hur, Ann. Med. (2000) vol 32, p 475 SINV TogaAlpha- / >5.5 TBEV FlaviFlavi >7.0 / >7.6 >5.2 >7.0 West Nile Virus,and relatives: model viruses, and WN V for „verification“ Family [-viridae] Genus [-virus] HSA (3.5% - 25%) pasteurization HSA (5% - 25%) pasteurization F VIII solvent-detergent ivIg solvent-detergent FEIBA vapor heating HCV FlaviHepaci(>5.0 *) (>5.0 *) - BVDV FlaviPesti>6.2 / >6.1 >6.8 / >4.9 >5.2 >4.9 >5.1 SINV TogaAlpha- / >5.5 >5.2 * B Horowitz & E Ben-Hur, Ann. Med. (2000) vol. 32, p. 475 TBEV WNV FlaviFlaviFlavi Flavi >7.0 / >7.6 >7.1 / >8.3 >8.3 / >8.0 >5.9 >6.0 >7.0 >8.1 West Nile Virus,and relatives /„model viruses“ P a s te u riz a tio n o f Hu m a n Alb u m in 8 log10 [TC ID50/ml] BV D V 3.5% 7 BV D V 25% 6 TB EV 3.5% TB EV 25% 5 SINV 25% W NV 3.5% 4 W NV 25% 3 2 limit o f d e te ctio n 1 0 0 100 200 300 400 incubation at 60°C [min] 500 600 West Nile Virus,and relatives /„model viruses“ Vapor Heating of FEIBA 8 60min 80 7 70min temperature profile 510min 60 TBEV (m2;99) 5 TBEV (92) 60min 4 BVDV (m2;01) BVDV (m2;99) 40 SINV (m3;88) 3 WNV (7%,02) WNV (8%,02) 2 1 20 limit of detection 0 0 lyo 0 200 400 time of heating [min] 600 Temperature [°C] log10 [TCID50/ml] 6 West Nile Virus,and relatives /„model viruses“ Solvent Detergent treatment of ivIg (only 5% !) 8 WNV run 1 WNV run 2 BVDV run 1 BVDV run 2 log10 [TCID50/ml] 6 4 2 0 B 0 10 limit of detection B B 20 30 BB 40 duration of SD treatment [min] 50 60 West Nile Virus „verification“ study • Asahi 15 N nanofiltration of α1-Proteinase Inhibitor Assay:N GI, SuperQuant™ RT PCR Assay forW N V spiked alpha-1-PI filtered alpha-1-PI reduction factor WNV (log10 genome copies/mL) >9.0 < 0.0 > 9.0 WNV Inactivation during HPPS Pasteurization 8.0 7.0 Log10 PFU WN 6.0 5.0 ≥ 7.3 log10 reduction 4.0 n=3 3.0 2.0 1.0 0.0 0 Limit of detection 5 Hours 10 WNV Inactivation during IGIV-S/D TNBP/Cholate Treatment 8 Log10 PFU WNV 7 6 > 5.9 log10 reduction (setpoint) > 6.2 log10 reduction (half conc.) 5 n=3 0.3% TNBP/0.2% Cholate 0.15% TNBP/0.1% Cholate 4 3 All values were at the limit of detection 2 1 0 0 2 4 Hours 6 Pasteurisation Inactivates Viruses (heat treatment in stabilised aqueous solution at 60°C) Beriglobin P (IMIG) 10 ] 7 6 Virus titre [log 5 BVDV WNV YFV SFV 4 3 2 Detection Limit WNV 1 Detection limit 0 0 2 4 6 Pasteurisation time [h] 8 10 Pasteurisation Inactivates Viruses (heat treatment in stabilised aqueous solution at 60°C) Gammar P (IVIG) 10 ] 7 6 Virus titre [log 5 BVDV WNV YFV SFV 4 3 2 Detection Limit WNV 1 Detection limit 0 0 2 4 6 Pasteurisation time [h] 8 10 West Nile Virus,W N V • FDA workshop: November 4 & 5, 2002 FDA /Final Guidance for Industry (October 2002): Recommendations forthe Assessment ofDonor Suitability and Blood and Blood Product Safety in Cases of Known or Suspected West Nile Virus Infection: „FDA has reviewed the viralreduction processesin place for all plasma derivatives. The methods in place have been validated to inactivate flaviviruses related to W N V.“ West Nile Virus,W N V • FDA workshop :November 4 & 5, 2002 – „The W N V data presented supportthe FD A‘s conclusion,in thatit „verifies“ that WNV does not behave differently than other flaviviruses.“ – „The conceptof using a range of physicochemically diverse model viruses forthe validation ofvirus reduction steps has also been verified,inthatthe behaviour of a virus ofinterest,i.e. W N V, has been adequately predicted !“ West Nile Virus,W N V • A successful precedentforthe collaboration of – Regulators – Academia – Patient organizations – Industry Result: efficient use of ressources, no unnecessary constraints; Æ to the ultimate benefit of concerned patients !! Thank you ! This paper was produced for a meeting organized by Health & Consumer Protection DG and represents the views of its author on the subject. These views have not been adopted or in any way approved by the Commission and should not be relied upon as a statement of the Commission's or Health & Consumer Protection DG's views. The European Commission does not guarantee the accuracy of the data included in this paper, nor does it accept responsibility for any use made thereof.