Safety, Pharmacokinetics and Efficacy of an ATIII Concentrate

To assess the safety, pharmacokinetics and efficacy of a plasma-derived AT-III concentrate in the treatment of subjects with congenital AT-III deficiency.

Inclusion Criteria: * Congenital ATIII deficiency documented by determination of plasma levels of ATIII off all therapies. Specifically, the baseline levels of ATIII activity should have been equal to or less than 60%. * Age \>12 years with a body weight of no less than 30 kg. * Subject must not have participated in another investigational study for at least 30 days. * For Segment II, enrollment required a pregnancy/delivery or a surgical procedure (it should have been a major surgery although data from a minor surgery would also have been collected). * For Segment II only, documented personal history of major thromboembolic or thrombotic event. * HIV, HBV, HCV, HAV and PARVO B19 status known prior to entry. * The subject must have been willing to comply with all aspects of the protocol, including blood sampling, for the duration of the study. * The subject signed an informed consent form (if at least 18 years old), or the subject's parent or legal guardian signed the informed consent form. Subjects below the age of 18 years were asked to sign an assent form. All consent and assent forms must have been approved in advance by the Institutional Review Board of the investigator's institution. * Patients with heparin-associated thrombocytopenia who required anticoagulation with non-heparin containing drugs were eligible if they could be safely transitioned during the washout period for the Segment I PK study. * If pregnant, a woman must have been Parvo B19 IgG antibody positive. Exclusion Criteria: * Acquired deficiency of ATIII. * Subject who received concomitant treatment for thrombophilic disorders other than ATIII deficiency. * History of anaphylactic reaction(s) to blood or blood components. * Allergies to excipients. * Liver function tests \>/= 2.5 X ULN * Serum creatinine \>1.2 X ULN. * Urine \>/= 2+ protein with urine dipstick test. * The subject was known to have abused alcohol or illicit drugs within the past 12 months. * The subject was unlikely to adhere to the protocol requirements of the study or was likely to be uncooperative or unable to provide a storage serum sample at the screening visit. * Patients on heparin-treatment who, for clinical reasons, could not safely be discontinued from heparin therapy during the PK segment.