BLOOD COMPONENTS AND BLOOD DERIVATIVES Marisa B. Marques, MD Transfusion Services Medical Director University of Alabama at Birmingham (UAB)

Nothing to disclose

Learning Objectives After participating in this activity, the learner will be able to: (1) Recall when to order modified blood components such as packed red blood cells (PRBCs) and platelets (2) Understand the rationale why plasma is no longer indicated for emergent warfarin reversal (3) Describe why activated coagulation factor concentrates are necessary to reverse the new oral anticoagulants in the absence of a specific antidote

Blood components Cellular: Packed red blood cells (PRBCS) Platelets, random (from whole blood) Platelets, apheresis Possible modifications (specifications): CMV-negative Leukoreduced Irradiated Washed (only PRBCs) Non-cellular: Plasma (FFP, FP24, thawed plasma, etc) Cryoprecipitate Above specifications do not apply

CMV negative PRBCs or platelets From donors who are negative for IgG anti-CMV When should we give it? Neonates/Intrauterine Transfusions CMV-Negative Pregnant Women Bone Marrow Transplant Patients In some states, blood centers do not test donors for anti-CMV IgG in donors – leukoreduced units are considered “CMV- safe”

Leukoreduction (LR) Filtration with specialized filters that bind 99.9% of WBC from donor unit LR essentially eliminates risk of: Febrile non-hemolytic transfusion reaction CMV, HLTV I-II Herpesviruses, EBV Trypanosoma cruzi Decreases risk of TRALI Universal LR is common practice

Irradiation Purpose To prevent lymphocyte proliferation in recipient and transfusion-associated graft-versus-host disease (TA-GVHD) Indications Stem cell transplant patients Must give at least 30 days before, and indefinitely after Recipients of blood products from 1st degree relatives Intrauterine transfusions & babies up to 4 months Congenital Immunodeficiency Syndromes Recipients of Fludarabine/Nelarabine/Clofarabine Some hospitals irradiate for all cancer patients – not an absolute indication

Washed PRBCs Purpose To remove supernatant (plasma proteins, K, additive solution, etc) Indications Severe IgA deficiency to prevent anaphylaxis Significant hyperkalemia Ongoing hemolysis from anti-A or anti-B History of repetitive allergic reactions Risk Contamination in the process of opening bag and adding saline multiple times - 24 hours of shelf-life

Special precaution re: ABO and Rh Storage and shelf-life Composition Blood comp. Special precaution re: ABO and Rh Storage and shelf-life Composition Usual dose PRBCs Must be ABO-compatible; Rh negative to Rh negative patients to prevent anti-D formation or when anti-D detected in antibody screen 1-6 C for 42 d in additive solution (AS-1, AS-3, AS-5); 1-6 C for 35 d in CPDA-1; if washed, expires in 24 h; irradiated, expires in 28 d Red blood cells with hematocrit ~55% (in AS) or ~80% in CPDA-1 One unit at a time unless ongoing bleeding to increase hemoglobin by 1 g/dL

Special precaution re: ABO and Rh Storage and shelf-life Composition Blood comp. Special precaution re: ABO and Rh Storage and shelf-life Composition Usual dose Plasma, thawed (from FFP or PF24) Must be ABO-compatible; Rh not important 2-6 C for 5 d (frozen, kept at -18 C for 12 months) All coagulation factors at 1 unit/mL; mostly water 10-15 mL/Kg of body weight to increase factor levels by 10-15%

Special precaution re: ABO and Rh Storage and shelf-life Composition Blood comp. Special precaution re: ABO and Rh Storage and shelf-life Composition Usual dose CRYO May not have to be ABO-compatible; Rh not important Room temperature for 4-6 h (frozen, kept at -18 C for 12 months) Fibrinogen (150-250 mg/single unit), Factor XIII, von Willebrand factor, Factor VIII, fibronectin 10 single units or 2 pooled units for adult with hypofibrinogenemia; may repeat if needed

Special precaution re: ABO and Rh Storage and shelf-life Composition Blood comp. Special precaution re: ABO and Rh Storage and shelf-life Composition Usual dose Platelets May be ABO-incompatible (preferably, low titer anti-A or anti-B); Rh identical to prevent anti-D; if anti-D detected in antibody screen, safe to give Rh positive unit 20-14 C with continuous gentle agitation for 5 d; same for irradiated units 5.5 x 1010 platelets per random unit (from whole blood); 3.0 x 1011 platelets per apheresis unit 4-6 random units or 1 apheresis unit to increase platelet count by 30,000-50,000/microliter

Anticoagulation Reversal (2) Understand the rationale why plasma is no longer indicated for emergent warfarin reversal (3) Describe why activated coagulation factor concentrates are necessary to reverse the new oral anticoagulants in the absence of a specific antidote

Warfarin Antagonizes Vitamin K II VII IX, X Protein C Protein S Warfarin antagonizes Vitamin K Warfarin acts as an anticoagulant by blocking the ability of Vitamin K to carboxylate the Vitamin K dependent clotting factors, thereby reducing their coagulant activity. Synthesis of non-functional coagulation factors = Deficiencies of all Vitamin-K dependent factors (procoagulants and anticoagulants)

Prothrombin Time to monitor warfarin (TF-VIIa) Prothrombin activation Thrombin Factor X activation Fibrin clot (time in s) Va Factors XII, PK/HMWK XI, VIII, IX PT starts here!

INR allows PT comparison between labs PT ratio corresponding to WHO International Reference Preparation thromboplastin Created solely to test patients on stable doses of warfarin Most patients target: INR 2-3 (few exceptions) NOT for pre-op evaluation, early oral anticoagulation, acquired vitamin K deficiency or hereditary factor deficiencies ( ) Patient’s PT in Seconds Mean Normal PT in Seconds INR = ISI

ACCP 2012 Chest Guidelines

ACCP 2012 Chest Guidelines

Four-factor PCC = Kcentra® Factors II, VII, IX, X, PC, and PS Labeled with number of factor IX units 520 (20 mL) or 1050 units (40 mL) Dose depends on INR and body weight: INR 2-4 – 25 units/Kg INR 4-6 – 35 units/Kg INR > 6 – 50 units/Kg Example: 80 Kg x 50 = 4,000 units of Kcentra® in 160 mL by slow IV push Maximum weight for calculation: 100Kg Inside the box:

Why not use plasma Contains all vitamin K-dependent factors, but highly diluted 4,000 units KCentra® = 14 -16 units of plasma (4L)!!! NO LONGER INDICATED FOR ANY TYPE OF ANTICOAGULANT-INDUCED BLEEDING Indications for plasma Massive transfusion DIC with bleeding Liver failure with bleeding

IV Vitamin K with Kcentra ensures hepatic production of factors within hours Low doses (1-2 mg) IV reduce INR value at 24 h Higher doses such as 5 -10 mg IV (for bleeding) reduce INR faster INR reduction begins in 2 h and correction to normal range in 24 h if normal hepatic function Endogenous production will keep INR low when effect of Kcentra wears off several hours later At 24 h, 5 mg of oral and 1 mg IV vitamin K produce similar effects on the INR as 5 -10 mg IV

IV Vitamin K risks Anaphylactoid reactions may occur with large IV doses given rapidly True frequency ≈ 3 per 10,000 doses More likely with formulations containing polyethoxylated castor oil (to maintain vitamin K in solution) To minimize risk of anaphylactoid reactions Mix vitamin K in a minimum of 50 mL of IV fluid and use an infusion pump to give over 20 minutes or more

Newer Oral Anticoagulants (since 2010) Direct thrombin Inhibitor Dabigatran Direct Xa inhibitors Apixaban Edoxaban Rivaroxaban All block coagulation activation instead of causing factor deficiencies Reason why replacing factors not indicated Reversal requires restoration of ability to form clot in presence of drug

Dabigatran (Pradaxa®) Elimination half-life: 12-17 hours; significantly longer in patients with decreased renal function – 80% excreted by kidneys Thrombin Time very sensitive (prolonged) when dabigatran in circulation (not quantitative); PT and PTT not useful If ingested in last 1-2 hours, consider activated charcoal; for emergent reversal, order the monoclonal antibody idarucizumab (Praxbind®) specific for dabigatran, 5 g IV once (2 x 2.5 g vials); for refractory bleeding, consider hemodialysis or a second dose of idarucizumab

Rivaroxaban (Xarelto®) Elimination half-life: Healthy: 5-9 hours Elderly: 11-13 hours Longer in patients with decreased renal function - 67% renal elimination Anti-Xa test useful to confirm drug in plasma (not quantitative) PT and PTT not useful because drug effect is quite variable on the different assays used in hospital laboratories Same patient’s blood sample may yield a normal and an abnormal result if tested in 2 laboratories using different methodologies and reagents

Apixaban (Eliquis®) Elimination half-life: 12 hours, range from 7 to 15 Longer in patients with decreased renal function - 33% renal elimination Anti-Xa test useful to confirm drug in plasma (not quantitative) PT and PTT not useful because drug effect is quite variable on the different assays used in hospital laboratories Same patient’s blood sample may yield a normal and an abnormal result if tested in 2 laboratories using different methodologies and reagents

Edoxaban (Savaysa®) Elimination half-life: 10-14 hours Longer in patients with decreased renal function - 50% renal elimination Anti-Xa test useful to confirm drug in plasma (not quantitative) PT and PTT not useful because drug effect is quite variable on the different assays used in hospital laboratories Same patient’s blood sample may yield a normal and an abnormal result if tested in 2 laboratories using different methodologies and reagents

Strategy to reverse direct Xa-inhibitors’ effect No specific inhibitor such as that available for dabigatran (see above) Reversal peptide being evaluated by FDA but not yet approved (Andexanet alfa: FXa Inhibitor Antidote) No evidence-based guidelines for reversal in emergencies; consider activated prothrombin complex concentrate (aPCC or FEIBA®) at 50 units/Kg (used in author’s institution) Others use PCC (Kcentra®) at 50 units/Kg Activated charcoal may be useful to inactivate apixaban if ingested in last 2-6 hours

Andexanet alfa: FXa Inhibitor Antidote A recombinant protein specifically designed to reverse the anticoagulant activity of both direct and indirect Factor Xa inhibitors Being developed as a universal reversal agent for patients anticoagulated with an oral or injectable Factor Xa inhibitor who experience a serious uncontrolled bleeding event or who require urgent or emergent surgery Designated a Breakthrough Therapy by the U.S. Food and Drug Administration Portola has commercial rights to andexanet alfa outside of Japan Clinical Development - Phase 3b/4 Currently being studied in ANNEXA-4, a Phase 3b/4 single-arm, open-label confirmatory study in patients receiving apixaban, rivaroxaban, edoxaban or enoxaparin (a low molecular weight heparin and indirect Factor Xa inhibitor) who present with an acute major bleed. On August 17, 2016, we received a Complete Response Letter, or CRL, regarding our BLA for andexanet alfa from the FDA, which raised questions regarding manufacturing and clinical data. We continue to have discussions with the FDA and plan to submit the BLA after we have addressed the deficiencies identified in the CRL. https://www.portola.com/clinical-development/andexanet-alfa-fxa-inhibitor-antidote/

Activated Prothrombin Complex Concentrate (aPCC) FEIBA® – Factor Eight Inhibitor Bypass Activity Approved for treatment of bleeding due to hemophilia A with inhibitor Combination of activated and inactive factors II, VII, IX, and X Risk of thrombosis No test to monitor FEIBA; patient’s clinical response only guide Maximum infusion/injection rate must not exceed 2 units/kg of body weight/minute For a 75-kg patient, approximately 2.5 -7.5 ml/minute, depending on the number of units/vial (see package insert)

Overanticoagulation with oral agents Drug PT PTT Anti-Xa Thrombin Time Warfarin Prolonged <0.1 units/ml Normal ApiXaban (Eliquis) NA > 1.8 units/ml EdoXaban (Savaysa) RivaroXaban (Xarelto) Dabigatran (Pradaxa) >60 s

Hemostatic options from the Blood Bank Plasma When you need all factors AND volume (massive bleeding) Cryoprecipitate For low fibrinogen Prothrombin Complex Concentrate (PCC) – Kcentra All vit K-dependent factors for prolonged PT (PTT) due to warfarin Activated Prothrombin Complex Concentrate (aPCC) - FEIBA Off-label use for anticoagulation reversal from direct Xa inhibitors Activated factor VII – NovoSeven Off-label use for massive bleeding