Skip to content

Recombinant Human Antithrombin (rhAT) in Patients With Hereditary Antithrombin Deficiency Undergoing Surgery or Delivery

A Multicenter, Multinational Study to Assess the Safety and Efficacy of Antithrombin Alfa in Hereditary Antithrombin (AT) Deficient Patients in High-Risk Situations for Thrombosis

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00110513
Enrollment
18
Registered
2005-05-11
Start date
2005-04-30
Completion date
2008-07-31
Last updated
2012-08-17

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Antithrombin III Deficiency

Keywords

Antithrombin Deficiency, Congenital or Hereditary, Antithrombin III Deficiency, ATIII, Hereditary Antithrombin Deficiency (HD)

Brief summary

Patients with hereditary antithrombin deficiency are at increased risk of venous thrombosis and pulmonary embolism, particularly during certain high risk procedures. The trial focused on patients with confirmed hereditary antithrombin deficiency who were undergoing a surgical procedure or induced/spontaneous labor and delivery, and/or caesarean section. The study assessed the incidence of thromboembolic events following prophylactic intravenous administration of recombinant human antithrombin (rhAT) to patients with hereditary antithrombin (AT) deficiency in situations usually associated with a high risk for thromboembolic events.

Detailed description

GTC Biotherapeutics established clinical trial sites in Europe, Canada, Australia, Austria and Canada. GTC Biotherapeutics provided an international clinical team to support site registration requirements once a patient was identified for treatment. GTC Biotherapeutics also provided consultation to help evaluate patient eligibility. In September 2006, GTC Biotherapeutics modified exclusion criteria 1 (below) to allow for the participation of previously excluded patients with the hereditary thrombophilic disorders Factor V Leiden and prothrombin gene mutation (G20210A).

Interventions

Up to 24 hours prior to the scheduled elective surgical procedure, caesarean section, or delivery induction, each patient will receive an initial intravenous loading dose followed by a continuous intravenous infusion of recombinant human antithrombin (rhAT) that will target and maintain an AT activity that is \> 80% and \< 120% of normal. The dosing objective for all study patients is maintenance of the AT activity at \> 80% and \< 120% of normal during the high-risk period for thromboembolic events. Dosing and dose adjustments will be based on the results of AT activity determinations performed prior to and during treatment.

Sponsors

rEVO Biologics
Lead SponsorINDUSTRY

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
No

Inclusion criteria

1. Have hereditary antithrombin deficiency (HD) with a personal history of venous thromboembolic events. 2. Have a history of HD that includes 2 or more plasma AT activity values ≤ 60%. 3. Be scheduled to have an elective procedure(s) known to be associated with a high risk for occurrence for DVT. This will include non-pregnant surgical patients or pregnant patients scheduled for caesarean section or delivery induction. 4. Be at least 18 years of age, not exceeding 80 years of age. 5. Have signed an informed consent form. 6. Have a negative serum pregnancy test at screening and a negative urine pregnancy test at baseline. This applies only to female non-pregnant surgical patients of childbearing potential. 7. Are able to comply with the requirements of the study protocol. In addition, hospitalized pregnant HD patients in active labor and eligible HD patients previously treated with rhAT were allowed entry into the study.

Exclusion criteria

1. Patients who have a diagnosis of another hereditary thrombophilic disorder (e.g. activated protein C(APC) resistance/Factor V Leiden, Protein S or C deficiency, prothrombin gene mutation (G20210A), or acquired (lupus anticoagulant) thrombophilic disorder). 2. Patients who have a baseline bilateral ultrasound positive for acute DVT or baseline diagnostic testing (if required) that is positive for a thromboembolic event other than acute DVT. 3. Patients who have a known allergy to goats or goat products. 4. Patients who have participated in a study employing a different investigational drug within 30 days of the start of their participation in the current trial. 5. Patients using fondaparinux sodium or the oral thrombin inhibitor, ximelagatran, or are expected to be treated with fondaparinux sodium or ximelagatran during the study period (up to 7 days after stop of treatment).

Design outcomes

Primary

MeasureTime frameDescription
Incidence of Thromboembolic Events Acute Deep Venous Thrombosis (DVT) and/or Thromboembolic Events Other Than Acute Deep Venous Thrombosis (DVT)During treatment and follow up period of 7 daysTo assess the incidence of thromboembolic events acute deep venous thrombosis (DVT) and/or thromboembolic events other than acute deep venous thrombosis (DVT) by clinical signs and symptoms of venous thromboembolism (VTE), confirmed by diagnostic assessments.

Countries

Australia, Austria, Canada, France, Germany, Italy, United Kingdom, United States

Participant flow

Recruitment details

The study population included non pregnant patients who were scheduled for surgery and pregnant patients who were scheduled for caesarean section or delivery induction or were hospitalized in active labor.

Pre-assignment details

Eighteen patients were treated with recombinant human antithrombin (rhAT) and analyzed for safety.

Participants by arm

ArmCount
Recombinant Human Antithrombin (rhAT) Infusion
Up to 24 hours prior to the scheduled elective surgical procedure, caesarean section, or delivery induction, each patient received an initial intravenous loading dose of recombinant human antithrombin (rhAT)followed by a continuous intravenous infusion dose of recombinant human antithrombin (rhAT) to maintain an antithrombin (AT) activity level of \>80% and \<120% of normal.
18
Total18

Baseline characteristics

CharacteristicRecombinant Human Antithrombin (rhAT) Infusion
Age, Categorical
<=18 years
0 Participants
Age, Categorical
>=65 years
0 Participants
Age, Categorical
Between 18 and 65 years
18 Participants
Age Continuous37.2 years
STANDARD_DEVIATION 12.2
Antithrombin (AT) activity level <60%18 Participants
Prior history of thromboembolism18 Participants
Region of Enrollment
Australia
1 participants
Region of Enrollment
Canada
2 participants
Region of Enrollment
France
3 participants
Region of Enrollment
Germany
1 participants
Region of Enrollment
Italy
1 participants
Region of Enrollment
United Kingdom
8 participants
Region of Enrollment
United States
2 participants
Sex: Female, Male
Female
14 Participants
Sex: Female, Male
Male
4 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
— / —
other
Total, other adverse events
16 / 18
serious
Total, serious adverse events
5 / 18

Outcome results

Primary

Incidence of Thromboembolic Events Acute Deep Venous Thrombosis (DVT) and/or Thromboembolic Events Other Than Acute Deep Venous Thrombosis (DVT)

To assess the incidence of thromboembolic events acute deep venous thrombosis (DVT) and/or thromboembolic events other than acute deep venous thrombosis (DVT) by clinical signs and symptoms of venous thromboembolism (VTE), confirmed by diagnostic assessments.

Time frame: During treatment and follow up period of 7 days

Population: Intent to treat population

ArmMeasureValue (NUMBER)
Recombinant Human Antithrombin (rhAT) InfusionIncidence of Thromboembolic Events Acute Deep Venous Thrombosis (DVT) and/or Thromboembolic Events Other Than Acute Deep Venous Thrombosis (DVT)0 Participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026