Increased risk of thrombosis in antiphospholipid syndrome patients treated with direct oral anticoagulants. Results from an international patient-level data meta-analysis

Rivaroxaban Versus Vitamin K Antagonist in Antiphospholipid Syndrome: A Randomized Noninferiority Trial

BACKGROUND

The potential role of new oral anticoagulants in antiphospholipid antibody syndrome (APS) remains uncertain.

OBJECTIVE

To determine whether rivaroxaban is noninferior to dose-adjusted vitamin K antagonists (VKAs) for thrombotic APS.

DESIGN

3-year, open-label, randomized noninferiority trial. (EU Clinical Trials Register: EUDRA [European Union Drug Regulatory Authorities] code 2010-019764-36).

SETTING

6 university hospitals in Spain.

PARTICIPANTS

190 adults (aged 18 to 75 years) with thrombotic APS.

INTERVENTION

Rivaroxaban (20 mg/d or 15 mg/d, according to renal function) versus dose-adjusted VKAs (target international normalized ratio, 2.0 to 3.0, or 3.1 to 4.0 in patients with a history of recurrent thrombosis).

MEASUREMENTS

The primary efficacy outcome was the proportion of patients with new thrombotic events; the primary safety outcome was major bleeding. The prespecified noninferiority margin for risk ratio (RR) was 1.40. Secondary outcomes included time to thrombosis, type of thrombosis, changes in biomarker levels, cardiovascular death, and nonmajor bleeding.

RESULTS

After 3 years of follow-up, recurrent thrombosis occurred in 11 patients (11.6%) in the rivaroxaban group and 6 (6.3%) in the VKA group (RR in the rivaroxaban group, 1.83 [95% CI, 0.71 to 4.76]). Stroke occurred more commonly in patients receiving rivaroxaban (9 events) than in those receiving VKAs (0 events) (corrected RR, 19.00 [CI, 1.12 to 321.9]). Major bleeding occurred in 6 patients (6.3%) in the rivaroxaban group and 7 (7.4%) in the VKA group (RR, 0.86 [CI, 0.30 to 2.46]). Post hoc analysis suggested an increased risk for recurrent thrombosis in rivaroxaban-treated patients with previous arterial thrombosis, livedo racemosa, or APS-related cardiac valvular disease.

LIMITATION

Anticoagulation intensity was not measured in the rivaroxaban group.

CONCLUSION

Rivaroxaban did not show noninferiority to dose-adjusted VKAs for thrombotic APS and, in fact, showed a non-statistically significant near doubling of the risk for recurrent thrombosis.

PRIMARY FUNDING SOURCE

Bayer Hispania.

EULAR recommendations for the management of antiphospholipid syndrome in adults

The objective was to develop evidence-based recommendations for the management of antiphospholipid syndrome (APS) in adults. Based on evidence from a systematic literature review and expert opinion, overarching principles and recommendations were formulated and voted. High-risk antiphospholipid antibody (aPL) profile is associated with greater risk for thrombotic and obstetric APS. Risk modification includes screening for and management of cardiovascular and venous thrombosis risk factors, patient education about treatment adherence, and lifestyle counselling. Low-dose aspirin (LDA) is recommended for asymptomatic aPL carriers, patients with systemic lupus erythematosus without prior thrombotic or obstetric APS, and non-pregnant women with a history of obstetric APS only, all with high-risk aPL profiles. Patients with APS and first unprovoked venous thrombosis should receive long-term treatment with vitamin K antagonists (VKA) with a target international normalised ratio (INR) of 2-3. In patients with APS with first arterial thrombosis, treatment with VKA with INR 2-3 or INR 3-4 is recommended, considering the individual's bleeding/thrombosis risk. Rivaroxaban should not be used in patients with APS with triple aPL positivity. For patients with recurrent arterial or venous thrombosis despite adequate treatment, addition of LDA, increase of INR target to 3-4 or switch to low molecular weight heparin may be considered. In women with prior obstetric APS, combination treatment with LDA and prophylactic dosage heparin during pregnancy is recommended. In patients with recurrent pregnancy complications, increase of heparin to therapeutic dose, addition of hydroxychloroquine or addition of low-dose prednisolone in the first trimester may be considered. These recommendations aim to guide treatment in adults with APS. High-quality evidence is limited, indicating a need for more research.

IgG Anti-high-Density Lipoproteins Antibodies Discriminate Between Arterial and Venous Events in Thrombotic Antiphospholipid Syndrome Patients

Introduction: Recurrent thrombotic events are a hallmark of Antiphospholipid Syndrome (APS). However, biomarkers to identify if a patient with antiphospholipid antibodies (aPL) is at higher risk to develop an arterial or a venous event are lacking. Recently, the pathogenic role of anti-high-density lipoproteins antibodies (anti-HDL) in the occurrence of cardiovascular disease (CVD) in autoimmunity has emerged. The aim of the present study was to evaluate the presence of IgG anti-HDL antibodies in a cohort of thrombotic APS patients and to investigate their association with clinical outcomes. Methods: Serum levels of IgG anti-HDL antibodies, total IgG, and complete aPL profile were assessed in 60 APS patients and 80 healthy donors (HDs) by immunoassays. Results: Higher levels of IgG anti-HDL were found in APS patients compared to HDs (p < 0.001), even after correcting for total IgG levels (p < 0.001). No associations with treatments or traditional cardiovascular risk factors, except for smoking habit (p < 0.0001), were found. Patients who experienced at least one arterial event (n = 30) had significantly higher levels of anti-HDL antibodies when compared to patients with venous thrombosis (n = 30, p = 0.046), this difference being stronger when adjusting for total IgG (p = 0.007). Additionally, patients tested positive for antiphosphatidylserine/prothrombin (IgG/IgM) antibodies had significantly higher levels of anti-HDL antibodies (p = 0.045). Conclusions: Increased levels of IgG anti-HDL antibodies can be found in APS, mainly in patients with arterial thrombosis, independently of aPL antibodies and traditional risk factors. These findings point to a role of anti-HDL antibodies in APS and support their use as a potential biomarker for arterial thrombotic events.

Treatment of the antiphospholipid syndrome with direct oral anticoagulantsPosition statement of German societies

The antiphospholipid-syndrome (APS) is one of the most severe forms of thrombophilia, which may not only lead to recurrent venous but also to arterial thromboembolic events (TE), and to severe pregnancy complications, respectively. APS is defined by clinical symptoms and specific laboratory findings: 1. Lupus anticoagulant (LA), 2. anticardiolipin-antibodies (ACA), and 3. β2-Glycoprotein I-antibodies (β2GPI-Ab). All test results have to be confirmed after at least 12 weeks. The thrombotic risk is highest, if all 3 test groups are positive. It must be pointed out that the presence of UFH, VKA or DOACs may lead to false positive LA-test results; the addition of a specific absorber after blood sampling may provide reliable results in the presence of DOACs. A prospective randomized controlled trial comparing warfarin and rivaroxaban (TRAPS-trial) including only high-risk patients with triple positive APS was terminated early because of an increased rate of TE in patients treated with rivaroxaban [19 %, mostly arterial, compared to 3 % with warfarin (HR 7.4;1.7-32.9)]. Subsequently, a warning letter was issued by the pharmaceutical manufacturers of DOACs, including a warning of DOAC use in APS-patients, particularly in triple-positive high-risk patients. Conclusions: 1. Clinical suspicion of APS requires careful diagnostic testing. Because of inadequate diagnostic workup, many patients may not even have an APS, and these patients could be adequately treated with a DOAC. 2. Patients with single or double positive antiphospholipid antibodies but without positive LA may have a comparably low thrombotic risk and may also be treated with a DOAC in venous TE - sufficient evidence for that conclusion is not yet available but is suggested by the results of meta-analyses. 3. Triple positive patients or those with APS who suffered from arterial thromboembolism have a very high recurrence risk of thrombosis; the TRAPS-Study shows that these patients should be treated with VKA instead of a DOAC.

Antiphospholipid syndrome: a clinical review

Antiphospholipid syndrome is characterised by recurrent thrombosis (arterial, venous, microvascular) and/or pregnancy complications in the presence of persistent antiphospholipid antibodies (lupus anticoagulant, anti-β2-glycoprotein 1 and anticardiolipin). It can be a primary disease or associated with another autoimmune disease (especially systemic lupus erythematosis). Testing for antiphospholipid antibodies should be considered in patients < 50 years of age with unprovoked venous or arterial thromboembolism, thrombosis at unusual sites or pregnancy complications. The mainstay of treatment is antithrombotic therapy and recommendations vary based on arterial, venous or pregnancy complications. If associated with systemic lupus erythematosis, hydroxychloroquine is recommended both as primary and secondary prophylaxis. Antithrombotic treatment is gold standard and effective.

Management of thrombotic and obstetric antiphospholipid syndrome: a systematic literature review informing the EULAR recommendations for the management of antiphospholipid syndrome in adults

Objective

To perform a systematic literature review (SLR) informing the European Lmmendations for the management of antiphospholipid syndrome (APS) in adults.

Methods

A SLR through January 2018 was performed. Research questions were constructed using the Patient, Intervention, Comparator, Outcome (PICO) format. We included data from articles that reported on each relevant intervention. Summary effect estimates were calculated for direct comparison studies that matched the PICO question exactly, and for studies with the relevant intervention and comparator. When meta-analyses were available, we used these estimates.

Results

From 7534 retrieved articles (+15 from hand searches), 188 articles were included in the review. In individuals with high-risk antiphospholipid antibody (aPL) profile without prior thrombotic or obstetric APS, two meta-analyses showed a protective effect of low-dose aspirin (LDA) against thrombosis. Two randomised controlled trials (RCTs) and three cohort studies showed no additional benefit of treatment with vitamin K antagonists at target international normalised ratio (INR) 3–4 versus INR 2–3 in patients with venous thrombosis. In patients with arterial thrombosis, two RCTs and two cohort studies showed no difference in risk of recurrent thrombosis between the two target INR groups. One open-label trial showed higher rates of thrombosis recurrences in triple aPL-positive patients treated with rivaroxaban than those treated with warfarin. RCTs and cohort studies showed that combination treatment with LDA and heparin was more effective than LDA alone in several types of obstetric APS. SLR results were limited by the indirect evidence and the heterogeneity of patient groups for some treatments, and only a few high-quality RCTs.

Conclusion

Well-designed studies of homogeneous APS patient populations are needed.

Comparing APLS and oranges: caution with the use of direct-acting oral anticoagulants (DOACs) instead of warfarin in the treatment of antiphospholipid syndrome (APLS)

A 63-year-old woman with known antiphospholipid syndrome (APLS) presented with catastrophic APLS and multiorgan dysfunction after a change in her anticoagulation from warfarin to rivaroxaban. Evidence suggests direct-acting oral anticoagulants (DOACs) like rivaroxaban may be less effective than warfarin in secondary prevention of thrombotic events in high-risk APLS patients.

Recurrent venous thromboembolism after discontinuation of rivaroxaban therapy in a patient with antiphospholipid syndrome

Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterised by thromboembolic events including venous thromboembolism (VTE) in association with the presence of antiphospholipid antibodies. The standard treatment of VTE historically consists of anticoagulation therapy with warfarin, a vitamin K antagonist. Recently, direct oral anticoagulants, including rivaroxaban have become available for the treatment of VTE. However, the choice of anticoagulant, and the duration of anticoagulation in patients with APS has not been determined yet due to lack of evidence. Here, we report a case of recurrent venous thrombosis after discontinuation of rivaroxaban therapy and avoiding sedentary lifestyle in a patient with APS. We suggest that indefinite anticoagulation therapy might be needed even in low-risk APS cases.