Efficacy and Safety Study of Argatroban to Treat Heparin-Induced Thrombocytopenia

Inclusion criteria

• Males of non-pregnant females >=20 and <=80 years of age
• Those with the diagnosis of HIT or HITTS made by the following diagnostic criteria, or those who have positive results of HIT antibody

• diagnostic criteria of HIT
• a fall in platelet count to less than 100,000/μL or a 50% decrease in platelets after the initiation of heparin therapy with no apparent explanation other than HIT
• diagnostic criteria of HITTS

• those who met the diagnosis criteria of HIT
• presence of an arterial or venous thrombosis documented by appropriate imaging technique (ultrasound, angiography etc.) or supported by clinical evidence such as a myocardial infarction, stroke, pulmonary embolism, or other clinical indications of vascular occlusion(absence of pulse, cold, cyanotic extremities, etc.)
• patients with history of HIT/HITTS with positive test results (HIT antibody or platelet function test) could be enrolled without present thrombocytopenia
• patients willing and able to give informed consent

Exclusion criteria

• any condition which in the investigator's opinion, contraindicated the use of argatroban or endangered the patient if he or she participated in this trial
• clinically significant or uncontrolled endocrine, renal, pulmonary, gastrointestinal, or psychiatric disorder of sufficient severity that the investigator deemed antithrombotic therapy with argatroban to be contraindicated
• unexplained aPTT>200% of control at baseline
• documented coagulation disorder or unexplained bleeding diathesis unrelated to HIT
• lumbar puncture within the past 7 days
• known clinical site of bleeding. Patients with a known site of clinical bleeding could be enrolled if the investigator deemed the risk of continued thrombosis outweighed the potential bleeding risk
• serious liver disfunction
• females of known or suspected pregnancy
• breast feeding females
• participation in other clinical drug trials within the past 30 days
• history of hypersensitivity to argatroban
• concomitant use of cimetidine
• previous participation in this trial