An Open-Label, Single-Arm, Pilot Intervention Study to Assess the Efficacy and Safety of Apixaban in Heparin-Induced Thrombocytopenia.

Heparin-induced thrombocytopenia (HIT) is a serious adverse drug reaction due to its related risk of life- and limb-threatening thrombosis. Apixaban is a direct factor Xa inhibitor that may be intended as an ideal alternative for the management of HIT. In this open-label, single-arm, pilot intervention study, the efficacy and safety of apixaban were evaluated in 30 patients aged >18 years with clinically suspected HIT (4Ts score ≥4 points). Patients with mechanical heart valves, chronic kidney disease, hepatic impairment, and active bleeding were excluded. In all patients with inclusion criteria, heparin or enoxaparin was discontinued and apixaban was started. The dose of apixaban for HIT suspected patients was defined on the basis of the reason for anticoagulant therapy. End points included confirmed thrombosis, mortality, and adverse treatment-related events. After apixaban therapy, platelet counts normalized in all patients; none of the 30 subjects developed new, progressive, or recurrent thrombosis; and only 1 of 30 patients developed a hemorrhagic event. Five patients (16.7%) died, but the reason for death was not linked to thrombosis, hemorrhage, or adverse effects of apixaban. Along with the available emerging data, our results propose that apixaban could be a safe and effective drug for the management of suspected HIT in clinically stable patients.