PB0436 - Long-term use of fondaparinux in patients with thrombotic antiphospholipid syndrome – A retrospective audit of clinical outcomes

Sunday, June 25, 2023

18:30 – 19:30 ET

Room: Exhibition

Co-Author(s)

BB

Buse Bor, Medical Student

Medical student
Faculty of Medicine, Aarhus University
Aarhus, Midtjylland, Denmark

Co-Author(s)

AD

Andrew J. Doyle

Consultant Haematologist
Centre for Haemostasis & Thrombosis, Guy’s & St Thomas’ NHS Foundation Trust, London, UK
London, England, United Kingdom
JB

John K. Bartoli- Abdou, n/a

Principal Pharmacist - Haemostasis & Thrombosis
Guy's & St Thomas' NHS Foundation Trust
London, England, United Kingdom
AH

Anthony Hackett

Senior Anticoagulation Pharmacist
Guy's & St Thomas' NHS Foundation Trust
London, England, United Kingdom
VC

Victoria Collings

Consultant Pharmacist - Haemostasis & Thrombosis
Centre for Haemostasis & Thrombosis, Guy’s & St Thomas’ NHS Foundation Trust, London, UK
London, England, United Kingdom
FO

Fatima Omrani

Specialist Pharmacist
Guy's & St Thomas' NHS Foundation Trust
London, England, United Kingdom
CF

Carl Foskett

Thrombosis Clinical Nurse Specialist
Guy's & St Thomas' NHS Foundation Trust
London, England, United Kingdom
AW

Anne Wareing

Thrombosis Clinical Nurse Specialist
Guy's & St Thomas' NHS Foundation Trust
London, England, United Kingdom
Karen A. Breen, MD

Consultant Haematologist
Guy's & St Thomas' NHS Foundation Trust
London, England, United Kingdom

Presenting Author(s)

Beverley J. Hunt, MD, FRCP, FRCPath

Professor of Thrombosis & Haemostasis, Consultant Haematologist
Guy's & St Thomas' NHS Foundation Trust
London, England, United Kingdom

Background: Vitamin K antagonists are the preferred anticoagulants for treating thrombotic antiphospholipid syndrome (TAPS), particularly with triple positivity or arterial events. However, thrombotic recurrence remains high despite anticoagulation, therefore alternative parenteral agents with predictable pharmacokinetics can be considered. Fondaparinux is not associated with heparin-associated thrombocytopenia and thrombosis seen with heparins. There is limited data on long-term fondaparinux use in TAPS.

Aims: To describe the efficacy and safety of long-term treatment with fondaparinux for TAPS.

Methods: A retrospective audit of electronic dispensary records selected those receiving long-term treatment with fondaparinux (>6 months) at a single centre. Clinical notes were reviewed for diagnosis, disease characteristics including thrombosis recurrence and bleeding.

Results: 46 patients were identified, 41 (89.1%) were female. The mean (SD) duration was 3.7 years with a total of 170 patient years (Table 1). In preceding thrombotic history: 22 had venous thromboembolism alone, 14 had arterial disease alone, 9 had both arterial and venous disease and 1 had thrombotic microangiopathy. In addition, 5 (12%) women had obstetric complications. Nine patients (19.6%) received concurrent antiplatelets (6 aspirin:2 clopidogrel:1 prasugrel) with 6 (13.0%) patients having arterial disease and 3 (6.5%) having recurrent thrombosis on anticoagulation. Fifteen patients (32.6%) used hydroxychloroquine.

One patient (1,2%) had recurrent thrombosis using fondaparinux (0.6/100 patient years) – this was cerebral ischemia showing on MRI scan. Twenty patients (43.5%) had bleeding complications: 13 mild (65%), 7 clinically relevant non-major bleeding (CRNMB) (35%), 3 major bleeding (15% - 1.8/100 patient years). One major bleed was following surgery, one following trauma and one spontaneous intracranial haemorrhage.

Conclusion(s): Our large case series of long-term fondaparinux use for TAPS showed thrombotic recurrences were infrequent and were cerebral events. Mild bleeding was common but spontaneous major bleeding was rare.