3.2.3. Apixaban

Apixaban (Eliquis®) directly and reversibly inhibits factor Xa. Maximal blood concentration of the drug is achieved 3–4 h after ingestion. As much as 87% of the drug is bound to blood protein. Twenty-seven percent of the drug is excreted through kidneys and the remainder through the liver. The drug half-life is 12 h [31]. Patients with atrial fibrillation are treated with 5 or 2.5 mg twice daily [32]. Patients with VTE are treated with 10 mg twice daily for the first 7 days followed by 5 mg daily [33]. The prophylactic dose for patients with total hip or knee replacement is 2.5 mg twice daily [34].

[4] Kitchen S, Jennings I, Woods TAL, Preston FE. Wide variability in the sensitivity of APTT reagents for monitoring of heparin dosage. Journal of Clinical Pathology. 1996;49(1):10-14

An Overview of the Anticoagulant Drugs Used in Routine Clinical Practice

http://dx.doi.org/10.5772/intechopen.76206

7

[5] Manzato F, Mengoni A, Grilenzoni A, Lippi G. Evaluation of the activated partial thromboplastin time (APTT) sensitivity to heparin using five commercial reagents: Implications for therapeutic monitoring. Clinical Chemistry and Laboratory Medicine. 1998;36(12):

[6] Toulon P, Boutiere B, Horellou M-H, Trzeciak MC. Monitoring heparin therapy using activated partial thromboplastin time—Results of a multicenter trial establishing the therapeutic range for SILIMAT, a reagent with high sensitivity to heparin. Thrombosis and

[7] Hirsh J, Warkentin TE, Shaughnessy SG, Anand SS, Halperin JL, Raschke R, Granger C, Ohman EM, Dalen JE. Heparin and low-molecular-weight heparin mechanisms of action, pharmacokinetics, dosing, monitoring, efficacy, and safety. Chest. 2001;119(1):64S-94S [8] Heit JA. Low-molecular-weight heparin: Biochemistry, pharmacology, and concurrent drug precautions. Regional Anesthesia and Pain Medicine. 1998;23(6 Suppl 2):135-139 [9] Collignon F, Frydman A, Caplain H, Ozoux ML, Le Roux Y, Bouthier J, Thébault JJ. Comparison of the pharmacokinetic profiles of three low molecular mass heparins dalteparin, enoxaparin and nadroparin—administered subcutaneously in healthy volunteers (doses for prevention of thromboembolism). Thrombosis and Haemostasis. 1995;

[10] Young E, Wells P, Holloway S, Weitz J, Hirsh J. Ex-vivo and in-vitro evidence that low molecular weight heparins exhibit less binding to plasma proteins than unfractionated

[11] Boneu B. Low molecular weight heparin therapy: Is monitoring needed? Thrombosis and

[12] Douxfils J, Tamigniau A, Chatelain B, Goffinet C, Dogne JM, Mullier F. Measurement of non-VKA oral anticoagulants versus classic ones: The appropriate use of hemostasis

[14] Peternel P, Terbižan M, Tratar G, Božič M, Horvat D, Salobir B, Stegnar M. Markers of hemostatic system activation during treatment of deep vein thrombosis with subcutaneous unfractionated or low-molecular weight heparin. Thrombosis Research. 2002;105:241-245

[15] Bauer KA, Hawkins DW, Peters PC, Petitou M, Herbert JM, van Boeckel CAA, Meuleman DG. Fondaparinux, a synthetic pentasaccharide: The first in a new class of antithrombotic agents—the selective factor Xa inhibitors. Cardiovascular Drug Reviews. 2002;20(1):37-52

[16] Hirsh J, Bauer KA, Donati MB, Gould M, Samama MM, Weitz JI. Parenteral anticoagulants: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

heparin. Thrombosis and Haemostasis. 1994;71(3):300-304

[13] Bates SM, Weitz JI. Coagulation assays. Circulation. 2005;112(4):e53-e60

975-980

73(4):630-640

Haemostasis. 1998;80:104-108

Haemostasis. 1994;72(3):330-334

assays. Thrombosis Journal. 2014;12:24

(8th edition). Chest. 2008;133(6 Suppl):141S-159S

No laboratory monitoring of therapy is needed due to the predictive effect of the drug. Apixaban unreliably prolongs APTT and PT. When an assessment of the drug blood level is needed, an anti-Xa test calibrated to apixaban should be used [35].
