Can we use NOACS in APS?

Effect of direct oral anticoagulants in cirrhosis: an in vitro study

BACKGROUND

Cirrhosis is associated with a procoagulant state that may worsen disease evolution. Anticoagulation could be of particular interest in these patients. However, evidence on the use of direct oral anticoagulants (DOAC) in patients with cirrhosis is limited.

OBJECTIVES

Our aim was to explore the in vitro effect of DOAC on thrombin generation (TG) in plasma from patients with cirrhosis compared to plasma from healthy controls.

METHODS

Platelet-poor-plasma was obtained from patients with cirrhosis (n = 87; Child-Turcotte-Pugh class: A, n = 68; B, n = 14; C, n = 5) and controls (n = 17). TG was assessed with ST-Genesia analyzer. Plasma from patients with cirrhosis and thrombomodulin-mediated inhibition of endogenous thrombin potential <20% (ThromboScreen) were defined as "highly procoagulant" (n = 36), ≥20% to 50% as "procoagulant" (n = 31), and >50% as "nonprocoagulant" (n = 20). Plasma samples were spiked with apixaban, edoxaban, rivaroxaban, or dabigatran at final concentrations of 50 and 150 ng/mL. TG was measured (DrugScreen) in plasma samples without and with DOAC.

RESULTS

Apixaban, edoxaban, and rivaroxaban demonstrated significantly reduced inhibition of in vitro TG parameters in highly procoagulant plasma from patients with cirrhosis compared to plasma from controls, whereas possibly artifactual results were observed with dabigatran.

CONCLUSION

The anticoagulant potency of DOAC differs according to the individual procoagulant potential. Highly procoagulant plasma from patients with cirrhosis is less sensitive to the anticoagulant action of apixaban, edoxaban, and rivaroxaban than control plasma. These results, if confirmed in vivo, would support the concept of personalizing anticoagulant treatment in patients with a highly procoagulant state.

Trial of Rivaroxaban in AntiPhospholipid Syndrome (TRAPS): Two-year outcomes after the study closure

BACKGROUND

Trial of Rivaroxaban in AntiPhospholipid Syndrome was a prospective randomized, open-label, noninferiority study conducted in 14 centers in Italy. Rivaroxaban was compared with warfarin for the prevention of thromboembolic events, major bleeding, and vascular death in high-risk, triple-positive patients with antiphospholipid syndrome.

OBJECTIVE

The aim of this paper is to report the events during the 2-year follow-up after the study closure.

METHODS

On January 28, 2018, the trial was prematurely stopped by adjudication and safety committee for an excess of events in the rivaroxaban group. Randomized patients were advised on trial results and those randomized to rivaroxaban were solicited to switch to warfarin. All 14 participating centers were asked and accepted to follow their patients for clinical events. This report describes the rate of events that occurred between January 28, 2018, and January 28, 2020.

RESULTS

Of 120 randomized patients, 115 were available for follow-up. Outcome events were two in six (33.3%) patients who remained on direct oral anticoagulants (DOACs) and six in 109 (5.7%) patients on warfarin (hazard ratio [HR] 6.9; 95% confidence interval [CI] 1.4-34.5, P = .018). The two patients on DOACs (one taking dabigatran and one taking rivaroxaban) suffered from thromboembolic events, whereas of the six patients with composite outcomes on warfarin, three had thromboembolic events (HR for thrombosis 13.3; 95% CI 2.2-79.9, P = .005).

CONCLUSION

These data further support the use of warfarin in high-risk patients with antiphospholipid syndrome.

Arterial thrombosis in antiphospholipid syndrome (APS): Clinical approach and treatment. A systematic review

Thrombotic Antiphospholipid Syndrome (APS) is a condition affecting young individuals in whom a thromboembolic event occurs in the presence of circulating antiphospholipid antibodies (aPL). An extensive body of literature has covered the most common clinical presentation of the syndrome, venous thromboembolism. Arterial thrombosis in APS, a lesser clinical expression, is less studied. This review will concentrate on the body of literature concerning pathogenesis, clinical presentation and management of arterial thrombosis in APS.

"Non-criteria" antiphospholipid syndrome: A nomenclature proposal

The classification criteria for antiphospholipid syndrome (APS) generate discussion, with a growing impression that certain patients not fulfilling these criteria might be inadequately excluded from the classification. Nonetheless, these "non-criteria" patients are heterogeneously defined across different publications. We reviewed the "non-criteria" APS subgroups depicted in the literature and attempted to organize these subsets in a nomenclature proposal that could be used for research purposes. We established four potential patient profiles, grouped under the broad term "non-criteria APS": (A) "Seronegative APS": patients fulfilling clinical criteria, plus "non-criteria" manifestations, with persistently negative antiphospholipid antibodies (aPL); (B) "Clinical non-criteria APS": patients with "non-criteria" manifestations, plus aPL positivity fulfilling the classification criteria; (C) "Incomplete laboratory APS": patients fulfilling clinical criteria, plus positive aPL, but not fulfilling the classification criteria (low titer aPL); and (D) "Laboratory non-criteria APS": patients fulfilling clinical criteria, with negative or low titer criteria aPL, plus positive "non-criteria" aPL. This categorization could allow for a more homogeneous research approach to APS, enabling more sustained and universal conclusions.