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Trial of Andexanet in Patients Receiving an Oral FXa Inhibitor Who Require Urgent Surgery (Annexa-S)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT04233073
Recruitment Status : Recruiting
First Posted : January 18, 2020
Last Update Posted : March 25, 2020
Information provided by (Responsible Party):
Portola Pharmaceuticals

Brief Summary:
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 Intervention/treatment Phase
Surgery Drug: andexanet alfa Phase 3

Detailed Description:
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.

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 200 participants
Allocation: N/A
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Prospective, Open-Label Study of Andexanet Alfa in Patients Receiving a Factor Xa Inhibitor Who Require Urgent Surgery
Actual Study Start Date : December 13, 2019
Estimated Primary Completion Date : March 30, 2022
Estimated Study Completion Date : July 31, 2022

Intervention Details:
  • Drug: andexanet alfa
    Andexanet is a recombinant version of human FXa
    Other Name: Andexxa®

Primary Outcome Measures :
  1. 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 :
  1. 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 ]

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   18 Years to 84 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • 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).

Exclusion Criteria:

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.
  • Heparin-induced thrombocytopenia.
  • 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.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT04233073

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Contact: Study Trial Contact (650) 246-7000

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United States, Michigan
Research Site MI Recruiting
Royal Oak, Michigan, United States, 48073
United States, New York
Research Site NY Recruiting
Staten Island, New York, United States, 10305
Sponsors and Collaborators
Portola Pharmaceuticals
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Responsible Party: Portola Pharmaceuticals Identifier: NCT04233073    
Other Study ID Numbers: 19-515
First Posted: January 18, 2020    Key Record Dates
Last Update Posted: March 25, 2020
Last Verified: March 2020
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Undecided

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Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Portola Pharmaceuticals:
Urgent Surgery