Trial of Andexanet in Patients Receiving an Oral FXa Inhibitor Who Require Urgent Surgery (Annexa-S)
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Prospective, open-label clinical trial to evaluate the efficacy and safety of andexanet alfa patients who require urgent surgery that have been anticoagulated with the FXa (activated factor X) inhibitors.
Condition or disease
Drug: andexanet alfa
This is a multicenter, prospective, open-label study to determine the efficacy and safety of andexanet in patients who require urgent surgery who have received 1 of the following FXa inhibitors: apixaban, rivaroxaban, edoxaban, or enoxaparin. The start of surgery must be within 15 hours following the last dose of FXa inhibitor. The primary efficacy outcome will be adjudicated by an independent Endpoint Adjudication Committee.
Proportion of patients with good or excellent intraoperative hemostatic efficacy as determined by the surgeon's assessment and confirmed by an independent adjudication committee [ Time Frame: At the end of surgery, not to exceed a total of 6.5 hours of andexanet dosing ]
Secondary Outcome Measures :
Percent change from baseline in anti-fXa activity [ Time Frame: At the end of surgery, not to exceed a total of 6.5 hours of andexanet dosing ]
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Layout table for eligibility information
Ages Eligible for Study:
18 Years to 84 Years (Adult, Older Adult)
Sexes Eligible for Study:
Accepts Healthy Volunteers:
Male or female patients aged 18 to 85 years.
Requires urgent surgery within 12 hours of consent, for which reversal of anti-fXa activity is necessary.
Received 1 of the following FXa inhibitors apixaban, rivaroxaban, edoxaban, or enoxaparin (dose of enoxaparin ≥ 1 mg/kg/d) within 15 hours prior to start of surgery.
Have a negative pregnancy test documented prior to enrollment (for women of childbearing potential).
If a patient meets any of the following criteria, he or she is not eligible to participate:
Surgery for which the risk of clinically meaningful uncontrolled or unmanageable bleeding is low.
Acute life-threatening bleeding (ISTH criteria) at the time of Screening.
Non-surgical interventional procedure or any surgical procedure requiring cardiopulmonary bypass, an intra-aortic catheter, or the intraoperative use of systemic, intravascular, unfractionated heparin.
Recent history (within 30 days prior to Screening) of venous thromboembolism (VTE), myocardial infarction (MI), disseminated intravascular coagulation (DIC); acute traumatic coagulopathy; cerebrovascular accident; transient ischemic attack; unstable angina pectoris hospitalization; or severe peripheral vascular disease.
Acute decompensated heart failure, cardiogenic shock, severe sepsis, septic shock, or hemorrhagic shock at the time of Screening.
Platelet count < 80,000/uL at the time of Screening.
Inherited coagulopathy (e.g., anti-phospholipid antibody syndrome, protein C/S deficiency, Factor V Leiden).
Last dose of apixaban < 2.5 mg, rivaroxaban < 10 mg, edoxaban < 30 mg, enoxaparin < 40 mg.
Pregnancy or breast-feeding.
Received drugs or blood products within 7 days of enrollment: Vitamin K antagonists, Dabigatran, Prothrombin complex concentrate products, recombinant factor VIIa (rfVIIa), Whole blood, plasma fractions. (Note: Administration of tranexamic acid (TXA), platelets, or packed red blood cells (PRBCs) is not an exclusion criterion).
Treatment with an investigational drug < 30 days prior to Screening or any prior treatment with andexanet.