Prior to initiation of the ARG-911 and ARG-915 clinical trials, there was no optimal replacement for
heparin anticoagulation in patients with
heparin-induced
thrombocytopenia (HIT) type II. These prospective, historical controlled studies were designed to determine the usefulness of
argatroban, a
direct thrombin inhibitor (DTI) that is not immunogenic and does not interact with
heparin antibody, in answering this clinical need. Clinical outcomes (37-day period) for 568
argatroban-treated and 193 control patients demonstrated significantly reduced risks of the primary efficacy composite endpoint (all-cause death, all-cause
amputation, new
thrombosis) and the secondary endpoints (death due to
thrombosis, new
thrombosis) with
argatroban.
Argatroban patients also experienced a more rapid recovery of platelet count.
Bleeding events were similar among both groups. It was concluded that
argatroban anticoagulation, compared with historical controls, improves clinical outcomes without increasing
bleeding risk in patients having HIT with or without
thrombosis.
Argatroban has since been approved in the US for both prophylaxis and treatment of
thrombosis in patients with HIT.
Argatroban has been used in
percutaneous coronary interventions in patients with and without HIT, for peripheral vascular procedures in both large and small vessels in HIT patients, and as an adjunct to
thrombolytic therapy for the treatment of AMI. Treatment success rates and the same or less
bleeding was demonstrated with
argatroban compared to
heparin controls. These pilot studies suggest that
argatroban will provide reliable anticoagulation during interventional procedures. A consistent safety profile of
argatroban has been demonstrated in all studies to date. The main attributes of
argatroban are its rapid onset of action, fast reversibility of its
anticoagulant effect, inhibition of clot-bound
thrombin, easily monitored by the aPTT and ACT and no dosage adjustment in renal-impaired individuals. These properties make
argatroban a predictable and useful
anticoagulant for HIT and non-HIT patients.