Apixaban

Indications

Apixaban is used for: Indicated to reduce risk of stroke and systemic embolism associated with nonvalvular atrial fibrillation, Postoperative Prophylaxis of DVT/PE following hip or knee replacement surgery, Deep venous thrombosis (DVT), Pulmonary embolism (PE),

Adult Dose

Oral Adult Prevention of VTE: Elective hip or knee replacement surgery Tablet 2.5 mg twice daily. Initial dose should be taken 12-24 hr post-op. Recommended duration of treatment: Patient undergoing hip replacement surgery 32-38 days. Patient undergoing knee replacement surgery 10-14 days. Prevention of stroke and systemic embolism in non-valvular atrial fibrillation Adult: 5 mg bid. Decrease dose to 2.5 mg PO BID in patients with any 2 of the following characteristics: Age ?80 years Weight ?60 kg Serum creatinine ?1.5 mg/dL Oral Deep vein thrombosis, Pulmonary embolism Adult: 10 mg bid for 7 days, followed by 5 mg bid. Prevention of recurrence: 2.5 mg bid after at least 6 mth of treatment. Hepatic impairment Mild: No dosage adjustment required Moderate: Patients may have intrinsic coagulation abnormalities; data are limited and no recommendations are available Severe: Not recommended

Child Dose

Renal Dose

Renal impairment, including with ESRD on dialysis Deep Vein Thrombosis: No dose adjustment recommended; clinical efficacy and safety studies did not enroll patients with ESRD on dialysis or patients with a CrCl <15 mL/min; dosing recommendations are based on pharmacokinetic and pharmacodynamic (anti-FXa activity) data in study subjects with ESRD maintained on dialysis Renal impairment (nonvalvular atrial fibrillation) Mild-to-moderate: No dosage adjustment required Serum creatinine ?1.5 mg/dL: Decrease dose to 2.5 mg BID if patient has 1 additional characteristic of age ?80 years or weight ?60 kg ESRD maintained on hemodialysis: 5 mg BID; decrease dose to 2.5 mg BID if 1 additional characteristic of age ?80 years or weight ?60 kg is present

Administration

May be taken with or without food.

Contra Indications

Hypersensitivity. Clinically significant active bleeding. Hepatic disease associated w/ coagulopathy & clinically relevant bleeding risk. Lesion or condition at significant risk of major bleeding. Concomitant treatment w/ other anticoagulant agent.

Precautions

Increased risk of hemorrhage eg, congenital or acquired bleeding disorders; active ulcerative GI disease; bacterial endocarditis; thrombocytopenia; platelet disorders; history of haemorrhagic stroke; severe uncontrolled HTN; recent brain, spinal or ophthalmological surgery. Discontinue use if severe haemorrhage occurs. Renal impairment (CrCl <15 mL/min). Contraindicated in patients w/ hepatic disease associated w/ coagulopathy & clinically relevant bleeding risk. Not recommended in patients w/ severe hepatic impairment. Patients w/ mild or moderate hepatic impairment (Child Pugh A or B). Low body wt (<60 kg). Patients receiving concomitant systemic treatment w/ strong inhibitors of both CYP3A4 & P-gp eg, azole antimycotics (eg, ketoconazole, itraconazole, voriconazole & posaconazole) & HIV-PIs (eg, ritonavir); strong CYP3A4 & P-gp inducers (eg, rifampin, phenytoin, carbamazepine, phenobarb or St. John's wort). Patients receiving concomitant systemic treatment w/ strong inducers of both CYP3A4 & P-gp for the prevention of VTE in elective hip or knee replacement surgery, stroke in patients w/ NVAF. Patients treated concomitantly w/ medicinal products affecting haemostasis eg, NSAIDs, acetylsalicylic acid, platelet aggregation inhibitors or other antithrombotic agents. Spinal/epidural anaesth or puncture. Hip fracture surgery. Patients w/ prosthetic heart valves w/ or w/o atrial fibrillation. Patients w/ rare hereditary problems of galactose intolerance, the Lapp-lactase deficiency or glucose-galactose malabsorption. Pregnancy & lactation. Childn <18 yr. Elderly. Lactation: Unknown whether distributed in human breast milk; rats excreted apixaban in milk (12% of the maternal dose) Women should be instructed either to discontinue breastfeeding or to discontinue apixaban therapy, taking into account the importance of the drug to the mother

Pregnancy-Lactation

Pregnancy There are no adequate and well-controlled studies in pregnant women Treatment is likely to increase the risk of hemorrhage during pregnancy and delivery Use of anticoagulants, during pregnancy, may increase risk of bleeding in fetus and neonate Pregnancy confers an increased risk of thromboembolism that is higher for women with underlying thromboembolic disease and certain high-risk pregnancy conditions Published data describe that women with a previous history of venous thrombosis are at high risk for recurrence during pregnancy Therapy should be administered during pregnancy only if the potential benefit outweighs the potential risk to the mother and fetus Animal studies Treatment of pregnant rats, rabbits, and mice after implantation until the end of gestation resulted in fetal exposure to apixaban, but was not associated with increased risk for fetal malformations or toxicity Labor and delivery All patients receiving anticoagulants, including pregnant women, are at risk for bleeding; use during labor or delivery in women who are receiving neuraxial anesthesia may result in epidural or spinal hematomas; consider use of a shorter acting anticoagulant as delivery approaches Consider the risks of bleeding and of stroke in this setting Lactation There are no data on presence of drug metabolites in human milk, effects on breastfed child, or the effects on milk production; the drug and/or its metabolites were present in milk of rats Rats excrete apixaban in milk (12% of the maternal dose) Because human exposure through milk is unknown, instruct women to either discontinue breastfeeding or to discontinue apixaban therapy, taking into account the importance of the drug to the mother

Interactions

Increased exposure w/ strong dual CYP3A4 and P-glycoprotein (P-gp) inhibitors (e.g. clarithromycin, itraconazole, ketoconazole, ritonavir). Increased risk of bleeding w/ drugs affecting haemostasis (e.g. aspirin, heparin, fibrinolytics, SSRIs, NSAIDs, serotonin norepinephrine reuptake inhibitors). Increased risk of stroke w/ strong dual CYP3A4 and P-gp inducers (e.g. rifampicin, phenytoin, carbamazepine).

Adverse Effects

Side effects of Apixaban : Epistaxis, haematoma, anaemia, haematuria, contusion, nausea; GI, rectal or gingival haemorrhage. Potentially Fatal: Epidural or spinal haematoma, fatal bleeding.

Mechanism of Action

Apixaban is an anticoagulant that inhibits platelet activation and fibrin clot formation via direct, selective and reversible inhibition of free and clot-bound factor Xa in both intrinsic and extrinsic coagulation pathways. Inhibition of coagulation factor Xa prevents conversion of thrombin and subsequent thrombus formation.