Plasma-Derived Products Pathogen Safety Of EVITHROM™ Thrombin, Topical (Human)

1. Plasma-Derived ProductsPathogen Safety Of EVITHROM™ Thrombin, Topical (Human) Bernard Horowitz, Ph.D. Horowitz Consultants, LLC

2. EVITHROM™ Thrombin, Topical (Human) Pathogen Safety -- Disclaimer Co-inventor of Solvent / Detergent (SD) Technology Board Member of Omrix

3. The majority of the data contained in this presentation is supported by the manuscript entitled, Estimating the Pathogen Safety of Manufactured Human Plasma Products: Application to Fibrin Sealants and to Thrombin by Bernard Horowitz and Michael Busch and submitted to and accepted by the journal, Transfusion. Reference

4. Indication: EVITHROM™ is indicated as an aid to hemostasis whenever oozing blood and minor bleeding from capillaries and small venules is accessible and control of bleeding by standard surgical techniques is ineffective or impractical. EVITHROM™ may be used in conjunction with an Absorbable Gelatin Sponge, USP. Important Safety Information: Do not inject EVITHROM™ directly into the circulatory system. Do not use for the treatment of severe or brisk arterial bleeding. Do not use in individuals known to have anaphylactic or severe systemic reaction to human blood products. EVITHROM™ is prepared from human plasma. Because this product is made from human plasma, it may carry a risk of transmitting infectious agents, such as viruses, and theoretically, the Creutzfeldt-Jakob disease (CJD) agent. There is a potential risk of thrombosis if absorbed systemically. Anaphylactic reactions may occur. Adverse events were reported in the clinical trial with similar frequency in the two study groups (EVITHROM™ or bovine thrombin group). The most common adverse event reported was procedural complications and pruritus. None of the adverse events reported was considered causally related to EVITHROM™ administration. Immunogenicity was evaluated by testing for the development of antibodies to highly purified antigens: human thrombin, human Factor V/Va, bovine thrombin and bovine Factor V/Va. None of the patients treated with EVITHROM™ developed antibodies to human thrombin or to human Factor V/Va. Direct comparison of incidence of antibody development following administration of EVITHROM™ with incidence of antibody development following administration of other products may be misleading and the clinical significance of these findings is unknown. EVITHROM™ Thrombin, Topical (Human) Please see representative for Full Prescribing Information

5. EVITHROM™ Thrombin, Topical (Human) Indication • Indicated as an aid to hemostasis whenever oozing blood and minor bleeding from capillaries and small venules is accessible and control of bleeding by standard surgical techniques is ineffective or impractical • May be used in conjunction with an Absorbable Gelatin Sponge, USP

6. Phase 3 Clinical Trial vs. Bovine Thrombin in Pts. Undergoing Surgery (n=305) • Primary outcome was hemostasis at 10 minutes post application; secondary outcomes included hemostasis at 3 and 6 minutes, blood loss, transfusions, time in specialty care units, procedure duration and LOS • Equivalence shown at all time points Cataldo Doria, Craig P. Fischer, Christopher G. Wood, P. Mark Li, Steven Marra, James Hart. Plasma-derived Human Thrombin Versus Bovine Thrombin in Achieving Hemostasis in Patients Undergoing Cardiovascular, Neurologic, and General Surgery 2007

7. EVITHROM™ Thrombin, Topical (Human) • Sizes: 2 mL, 5 mL, 20 mL • 800-1200 IU/ml of human thrombin • Removable flip-off caps • Shipped frozen • Thawing conditions • 24 hrs in refrigerator (2-8C) • 1 hr at room temp (20-25C) • 10 min at 37C for 2 mL & 5 mL vials only (temp cannot exceed 37C, time cannot exceed 10 min) • Cannot refreeze or re-refrigerate • Shelf life • 2 years in freezer (-18C) • 30 days in refrigerator (2-8C) • 24 hours at room temp (20-25C)

8. Healthy Donor Safety Plasma Screening Viral Inactivation High Purity (Removal) Pathogen Safety Paradigm

9. Ancient History – 1980s • Early / mid-1980s, frequent transmission of HIV and HCV to recipients of single donor blood products • >90% of hemophilia patients were infected with HIV, HCV, and / or HBV • HIV screening implemented in 1985; HCV screening in 1988-1989

10. Ancient History – 1980s • Viral inactivation introduced mid-1980s • Heat or SD (nano-filtration came later) • Advanced purification techniques (e.g., affinity chromatography) applied to coagulation factor concentrates • Numerous viral inactivation / removal studies published; marker viruses used • Numerous clinical studies assessing viral safety published

11. Blood Protein Derivative Viral Safety: Observations and AnalysisYale J Biol Med 63. 361-9, 1990 • Viral clearance compared to viral loads, estimating safety margins and virus risk / vial • Paper’s Conclusion:“Based on viral load analysis, modern coagulation factor concentrates are predicted to have the same probability of freedom from HIV, HBV and HCV transmission as that exhibited by albumin”

12. Comparison of Viral Safety of AHF with HBV Safety of Albumin

13. Clinical Safety Outcome • There has not been a documented transmission of HIV, HBV, or HCV (or any other enveloped virus) by a virally inactivated plasma derivative in the USA since 1987 • European experience similar since early 1990s Burnouf, T. Modern plasma fractionation. Transfusion Medicine Reviews, 2007; 21(2):101-117

14. SD-Treated Product Usage1985-1997(updated from Horowitz et al, Dev Biol Standards, 1993)

15. Safety MarginImprovements Implemented in Past Decade • Viral loads were reduced • Plasma collection standards have become more stringent • Serologic screening tests have become more sensitive • NAT deployed • Reduces the number of infectious units entering the pool AND the titer of those units • Viral elimination was increased • Manufacturing processes have become more robust • Double VI • Higher purity • Facilities have been upgraded • Oversight is enhanced • QA and regulatory oversight have increased • Surveillance has improved

16. Evolution of Transfusion Risks Near “Eradication” of Major Viruses 1:100 Modified from Busch et al. JAMA 2003; 289: 959-62. 1:1000 HCV Risk per unit 1:10 000 HBV 1:100 000 HIV 1:1 000 000 2000 2002 1998 1984 1986 1988 1990 1992 1994 1996 JA-Jan03

17. “Estimating the Pathogen Safety of Manufactured Human Plasma Products: Application to Fibrin Sealants and to Thrombin” • Update of 1990 paper comparing viral loads to clearance capacity • More known about viral loads • Includes non-enveloped viruses and vCJD • Improvements in blood screening • Improvements in manufacture • Co-authored by Michael Busch, MD, Ph.D Transfusion, 2008, In Press

18. Pathogens Bacteria and Parasites Viruses Prions • Removed by terminal sterile filtration • Enveloped • HIV, HBV, HVC • Non-enveloped • HAV, Parvovirus • Classic CJD • vCJD

19. Estimating the Safety Margin • Safety Margin = Clearance factor (CF) / viral load (VL) • Examples: • If clearance is 1000 infectious units (IU) and load is 100 IU, then Safety Margin = 10-fold • If CF is 10 logs and load is 6 logs, Safety Margin = 4 logs (i.e., 10,000-fold)

20. Viral Load • VL = Number of contaminated units that enter the plasma pool x Quantity of virus contained in those units • Window units • Are of greatest concern because they usually contain the most virus – 105 to 107 GE / unit • Infectivity may be 100-fold lower NAT eliminates these units

21. HCV Markers During Early InfectionAdvantages of NAT(From Michael Busch) Anti-HCV EIAs 1st gen 150 d2nd gen 80 d 3rd gen 70 d Plateau Phase Viremia: 105-108 gEq/mL HCV RNA Ramp-up Phase DT = 17 .7 hrs Viral Set-point: 102-107 gEq/mL - HCV Ag EIA - HCV MP-NAT Pre-ramp-up Blip Viremia ALT - HCV ID-NAT 0 10 20 30 40 50 60 70 80 90 100

22. Parvovirus B19 DNA in Manufacturing Pools(From Thomas Kreil, Baxter) Prior to B19 in-process NAT After B19 in-process NAT Implementation Viral Loads Significantly Reduced Via NAT

23. Viral Load

24. Thrombin Viral Clearance Factors

25. Estimating Clearance Factors • Measured clearance • GLP studies under validated conditions • Complementary (orthagonal) elimination procedures • Reserve capacity • Undocumented clearance factors • Reference to calculations: Horowitz and Busch, Transfusion, 2008, in press

26. Viral Load

27. Thrombin Viral Clearance Factors

28. Additional Virus Clearance FactorsSD Reserve Capacity – VSV Kill

29. Defining Reserve CapacityAn Approximation

30. Additional Viral Clearance Factors

31. Safety Margin Summary

32. Safety Margin Summary

33. Safety Margin Summary

34. Clinical Safety OutcomeHIV, HBV, HCV • There has not been a documented transmission of HIV, HBV, or HCV (or any other enveloped virus) by a virally inactivated plasma derivative in the USA since 1987 • European experience similar since early 1990s Burnouf, T. Modern plasma fractionation. Transfusion Medicine Reviews, 2007; 21(2):101-117

35. Clinical Safety OutcomeHAV • Not transmitted by products utilizing dedicated viral inactivation / removal step shown to eliminate as little as 3-4 logs HAV • Not transmitted by heat-treated products • Not transmitted by nano-filtered products

36. Clinical Safety OutcomeParvovirus • Titers can reach >1010 GE/mL; Ab is protective • Transmitted by AHF concentrates despite heat-treatment or immunopurification • Transmitted by SD-Plasma to susceptible individuals if titer in plasma exceeded 106 GE/mL; not transmitted if titer ≤104 GE/mL • NAT implemented for both SD-plasma and purified products • No documented transmissions by a heat-treated or nano-filtered plasma derivative since NAT was introduced

37. Prion Risk – Preclinical Studies • Very low levels (~20 ID/mL) of infectivity found in animal plasma • Removal • PrP concentrates in virtually all precipitates • PrP removed during filtration with filter aids • 3.9 log removal demonstrated by the anion exchange chromatography step used in the manufacture of pdAHF

38. Prion Safety *Based on data published by PR Foster

39. Prion Clinical Safety Outcome • No transmission of CJD to individuals with hemophilia • No transmission of vCJD to individuals with hemophilia • No transmission of either CJD or vCJD with any purified plasma derivative • Conclusion: Risk associated with purified plasma products remains theoretical

40. Clinical Safety OutcomeSummary • Plasma-derived products have an outstanding pathogen safety record • Enveloped viruses dealt with successfully for over 2 decades • Non-enveloped viruses req’d further advances implemented in last decade • Omrix’s thrombin has been used clinically for almost a decade as a component of fibrin sealant • Annually, the industry processes 20-25 million liters of plasma / year and produces over 60 million vials of product valued at over $5 billion

41. FDA Approved Labeling • EVITHROMTM Package Insert • “The risk of transmitting an infectious agent has been reduced by screening plasma donors…by testing…and by inactivating and removing certain viruses; despite these measures, such products can still potentially transmit disease”

42. FDA Approved Labeling • Gamunex Package Insert • “Because this product is made from human blood, it may carry a risk of transmitting infectious agents, e.g., viruses that can cause disease” • “The risk…has been reduced by screening, by…testing, and by…inactivating and / or removing” • “Despite these measures, such products can still potentially transmit disease”

43. Healthy Donor Safety Plasma Screening Viral Inactivation High Purity (Removal) Pathogen Safety Paradigm

44. Recombinant ProductsFDA Points to Consider -- 1985 • “Although rDNA products may be demonstrated to be 99% pure, the purification process should be designed to specifically eliminate • Detectable viruses, • Microbial and nucleic acid contamination, • Undesirable antigenic materials”

45. RECOTHROMTM • Manufacture • Made in Chinese hamster ovary (CHO) cells • Uses animal thrombin activator • Viral inactivation (SD + nano-filtration) • Immunogenicity RECOTHROMTM Full Prescribing Information 2008

46. RECOTHROMTM Immunogenicity* • 3/198 patients developed specific antibodies to rThrombin • 1/198 patients developed anti-CHO cell protein antibodies • “Limited data (n = 6) are available on repeat exposure to RECOTHROMTM” • Post-marketing study of immunogenicity and safety of re-exposure demanded by FDA *The detection of antibody formation is highly dependent upon the sensitivity and specificity of the assay. The absolute immunogenicity rates reported here are difficult to compare with results from studies of other products due to differences in assay methodology, patient populations, and other underlying factors. RECOTHROMTM Full Prescribing Information 2008

47. Immunogenicity* *The detection of antibody formation is highly dependent upon the sensitivity and specificity of the assay. The observed incidence of a positive signal in an assay may be influenced by several factors including the timing of the sampling, sample handling, concomitant medications, or underlying disease. Therefore, direct comparison of incidence of antibody development to human or bovine thrombin or Factor V/Va following administration of EVITHROM™ with incidence of antibody development following administration of other products may be misleading and the clinical significance of these findings is unknown. EVITHROM™ Full Prescribing Information 2007

48. Schering Submission to FDANov. 23, 2004 Schering submission to FDA, Nov. 23, 2004

49. Antibodies to Interferon-Alpha2A Schering submission to FDA, Nov. 23, 2004

50. Violative AdvertisingUnsubstantiated Safety Claims by Manufacturers of Recombinant Products • FDA letters to Bayer and Wyeth (2004) • “The cited material is false or misleading because it contains a safety and superiority claim that, to our knowledge, has not been demonstrated by substantial evidence or substantial clinical experience” • “FDA is unaware of any data supporting the claim that your product has better viral safety than any other antihemophilic factor”