PB0411 - Hydroxychloroquine as an adjunct treatment for patients with triple positive thrombotic antiphospholipid syndrome- a single centre experience

Sunday, July 10, 2022

6:30 PM – 7:30 PM

Location: Exhibition

Presentation Format: In-Person

Presenting Author(s)

Christina Crossette-Thambiah, MBBS, BSc, MRCP

Haematology Specialist Registrar and Clinical Research Fellow
Imperial College London
London, England, United Kingdom

Co-Author(s)

Michael A. Laffan, MD

Professor
Centre for Haematology, Imperial College London, London, UK
London, England, United Kingdom
DA

Deepa J. Arachchillage, MD

consultant haematologist
Imperial College London
London, England, United Kingdom

Background: Hydroxychloroquine (HCQ) is an antimalarial drug that has been used for many years for the treatment of inflammatory rheumatic diseases, especially systemic lupus erythematous (SLE). Evidence suggests that HCQ has anticoagulant and antiplatelet effects in addition to anti-inflammatory effects. Therefore, it would be an attractive option for patients with antiphospholipid syndrome (APS) especially those with triple positive APS carrying the highest risk of recurrence despite adequate anticoagulation. However, use of HCQ is the not the standard treatment for patients with APS.

Aims: To determine the benefit of HCQ in patients with triple positive APS as adjunct treatment with warfarin.

Methods: We performed a 3-year follow-up 23 triple positive thrombotic APS treated with HCQ 200mg once or twice daily in combination with warfarin in a single UK centre.

Results: Median age was 47 (range 22-74) years and 67% were female. Baseline characteristics of are summarised in Table 1. Prior to commencing HCQ 23 patients, 43.5% (10/23) had had ischaemic stroke, one catastrophic APS and the remainder venous thromboembolism (VTE). Of the 10 patients with stroke, 80% (8/10) were treated with warfarin to target INR of 2.5 (2.0-3.0) and two (20%) to INR of 3.5 (3.0-4.0) due to recurrent thrombosis. All stroke patients had an annual MRI brain to detect new white matter lesions or evidence of new infarction or silent bleeding events. All demonstrated only the expected interval maturation with no progression of lesions or bleeding. None of the 23 patients developed recurrent thrombosis or bleeding over 3-year follow-up. All patients had ophthalmology review but none developed retinal toxicity or other side effects.

Conclusion(s): These data support the use of HCQ in patients with triple positive APS on standard intensity anticoagulation with warfarin to prevent thrombosis recurrence without significant increase in bleeding or other complications.