Because of an extreme risk for thromboemboli, patients with suspected
heparin-induced
thrombocytopenia (HIT) require immediate initiation of an alternative
anticoagulant. The only
therapies approved by the Food and Drug Administration require
intravenous infusion of expensive
direct thrombin inhibitors. This prospective, randomized, open-label, exploratory study compared the clinical and economic utility of subcutaneous
desirudin vs
argatroban, the most frequently used agent for suspected or immunologically confirmed HIT, with or without
thrombosis. Sixteen patients were randomized to treatment with fixed-dose
desirudin (15 or 30 mg) every 12 hours or activated partial thromboplastin time-adjusted
argatroban by
intravenous infusion. Arm A included 8 patients naive to
direct thrombin inhibitor therapy, whereas Arm B included 8 patients on
argatroban for at least 24 hours before randomization. The primary efficacy measure was the composite of new or worsening
thrombosis (objectively documented),
amputation, or death. Other end points included major and minor
bleeding while on
drug therapy, time to platelet count recovery, and pharmacoeconomics. No
amputations or deaths occurred. One patient randomized to
argatroban had worsening of an existing
thrombosis. Major
bleeding occurred in 2 patients on
argatroban and in none during
desirudin treatment. There was 1 minor bleed in each treatment group. The average medication cost per course of treatment was $1688 for
desirudin and $8250 for
argatroban.
Desirudin warrants further study as a potentially cost-effective alternative to
argatroban in patients with suspected HIT.