Scientific Poster Session III - Encore

Encore Presentations
  Monday, November 13, 2023
  01:00 PM–02:30 PM

Abstract

Background/Aims: FXa inhibitor-related ICH have high rates of hematoma expansion leading to increased risk of death/disability. Andexanet alfa is a modified recombinant FXa decoy that rapidly reverses the anticoagulant effect of FXa inhibitors. ANNEXa-I is an international, prospective, randomized, open-label, blinded end-point trial that is evaluating whether andexanet alfa is superior to usual medical care for achieving hemostasis in acute FXa inhibitor-related ICH.

Methods: Participants aged =18 years with acute ICH within 6 hours from symptom onset, hematoma volume of =0.5 to =60 mL, and treatment with an oral FXa inhibitor within 15 hours prior to randomization (or documented anti-FXa activity >100 ng/mL) are eligible. Excluded are patients with NIHSS>35, GCS<7, planned hematoma evacuation surgery, or recent history of thromboembolism. Consenting participants are randomized (1:1) to usual medical therapy or one of two dosing regimens of andexanet determined according to the strength and timing of their last FXa inhibitor dose.

Results: The primary outcome is hemostatic efficacy. With a target of 900 patients and an expected hemostatic efficacy rate of 70% in the usual care arm, the study will have 90% power to detect a 10% absolute difference in the rate of hemostatic efficacy with andexanet vs. usual medical therapy. Recruitment has commenced and will continue at a 216 sites in 24 countries.

Conclusion: ANNEXa-I will provide important answers to unresolved questions surrounding the optimal management of acute FXa inhibitor-related ICH.

Presenting Author

Ashkan Shoamanesh MD
McMaster University/Population Health Research Institute

Authors

Pierre Amarenco MD
Bichat Claude-Bernard Hospital

Daniel Bereczki MD, PhD, DSc, FRCP Edin, FESO
Semmelweis University

Jan Beyer-Westendorf MD, PhD
University Hospital Dresden

Mikael Knutsson PhD
AstraZeneca

Wilfried Lang MD
Hospital of St. John of God

Andrew Law MBBS
Alexion Pharmaceuticals UK Ltd

Robin Lemmens MD, PhD
University Hospitals Leuven

Arne G. Lindgren MD, PhD
Lund University, Skane University Hospital

Anders Himmelmann MD, PhD
AstraZeneca

Saskia Middledorp MD
Radboud University Medical Center

Robert Mikulik PhD
St. Anne’s University Hospital/Masaryk University

Truman John Milling Jr. MD, FACEP
Dell Medical School, University of Texas

Carlos A. Molina MD, PhD
Vall d’Hebron University Hospital

Hanne Christensen MD, PhD, DMSci, FESO
Copenhagen University Hospital, Bispebjerg Hospital

Alexander T. Cohen MBBS, MSc, MD, FRACP, FESC, FRCP
Guy's and St Thomas' NHS Foundation Trust

ANNEXa-I Steering Committee -
McMaster University/Population Health Research Institute

Stuart J. Connolly MD, FRCPC
McMaster University

Jonathan M. Coutinho MD, PhD
Amsterdam University Medical Centers

Mark Crowther MD, MSc, FRCPC, FRSC
McMaster University

Anna Czlonkowska MD, PhD
Institute of Psychiatry and Neurology

Andrew M. Demchuk MD
Cumming School of Medicine, University of Calgary

Ella Ekholm MD, PhD
AstraZeneca

David Tanne MD
Rambam Health Care Campus

Vitor Tedim-Cruz MD, PhD
University of Porto

Danilo Toni MD, PhD
Sapienza University of Rome

Georgios Tsivgoulis MD, PhD
National and Kapodistrian University of Athens, “Attikon” University Hospital

Roland Veltkamp MD
Imperial College

Peter Verhamme MD, PhD
University of Leuven

Thompson Robinson MD, FRCP, FESO
Leicester University

Risto O. Roine MD, PhD
Turku University Hospital

Else Charlotte Sandset MD, PhD
Oslo University Hospital

David Seiffge MD
Inselspital

Mukul A. Sharma MD
McMaster University/Population Health Research Institute