ClinicalTrials.gg
RecruitingNCT04918173Updated Sep 28, 2026

Efficacy of Atenativ in Patients With Congenital Antithrombin Deficiency Undergoing Surgery or Delivery

A Phase 3 interventional study of Atenativ in Congenital Antithrombin Deficiency, sponsored by Octapharma. Recruiting at 30 sites in 14 countries. Open to participants aged 12 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-09-28.

Sponsored by Octapharma · Phase 3, Interventional, and Prevention

From the registry’s dates

  • Started Jul 2022; still recruiting 4 years 4 months later.
Updated Sep 28, 20268 sites added8 sites removedGo to Updates ↓
Phase
Phase 3
Study type
Interventional
Enrollment
38
Allocation
Not applicable
Ages
12 Years to 80 Years
Sex
All
01

Study summary

The goal of this study is to assess the incidence of the composite of thrombotic events (TEs) and thromboembolic events (TEEs) in patients with congenital antithrombin deficiency under when they receive Atenativ for surgical procedures or parturition.

02

Conditions studied

  • Congenital Antithrombin Deficiency
03

In context

Lead sponsor

Octapharma is the lead sponsor of 71 studies on the registry; 8 are open to participants now.

Of its 17 completed or terminated interventional studies of FDA-regulated products, 16 (94%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
12 Years to 80 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  1. Adult male or female patients ≥18 and ≤80 years of age. Solely in the US, 4 male or female patients between ≥12 and \<17 years of age will be enrolled into the PK phase, and subsequently in the treatment phase, if applicable
  2. Documented congenital antithrombin deficiency, defined by plasma activity level of antithrombin ≤60% from medical history
  3. Personal or family history of TEs or TEEs (except for PK patients)
  4. For the Treatment Phase: either a) non-pregnant surgical patients scheduled for elective surgical procedure(s) known to be associated with a high risk for occurrence of TEs or TEEs, or b) pregnant patients of at least 27 weeks gestational age who are scheduled for caesarean section or delivery
  5. For female patients of entering the PK Phase who are not known to be pregnant, and for female surgical patients of childbearing potential entering the Treatment Phase for any procedure other than caesarean section or delivery, a negative urine pregnancy test at screening and at baseline
  6. Patient has provided

Exclusion criteria

Exclusion Criteria:

  1. Requires emergency surgery or emergency caesarean section
  2. Has undergone surgery within the last 6 weeks
  3. History or suspicion of another hereditary thrombophilic disorder other than antithrombin deficiency (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)
  4. , renal failure (patients on renal replacement therapy), or severe liver disease ( [ASAT] >5 times the )
  5. >40 kg/m2 (for non-pregnant patients, only)
  6. Known or allergic reaction to antithrombin or any of the in Atenativ
  7. History of anaphylactic reaction(s) to blood or blood components
  8. Refusal to receive transfusion of blood-derived products
  9. Administration of any antithrombin concentrate or antithrombin-containing blood product within 14 days of either of the two phases of the study
  10. Prior diagnosis of heparin-induced thrombocytopenia
  11. TE or TEE within the last 6 months
  12. Female patients who are nursing at the time of screening*
  13. Have participated in another study within the last 30 days
  14. Persons dependent on the sponsor, the investigator or the centre of investigation
  15. Persons placed in an institution by administrative or judicial order

    • criterion does not include female patients who plan to breastfeed after giving birth
Terms in these criteria, in plain language(9)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Childbearing potential

Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).

Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Cancer (malignancy)

Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.

Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.

ALT and AST (liver enzymes)

Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.

Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.

ULN (upper limit of normal)

The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.

“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.

BMI (body mass index)

Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.

What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.

Hypersensitivity

An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.

Excipients

The other ingredients in a medicine besides the active drug, such as fillers, colours or preservatives.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

05

Study design

Phase
Phase 3
Primary purpose
Prevention
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrollment
38 participants (estimated)

Study arms

  • Experimental
    Atenativ treatment

    During the PK phase, patients will receive a 60 IU/kg Atenativ as a single intravenous infusion for PK analysis. During the treatment phase, patients will receive a single intravenous loading dose followed by maintenance doses administered every 24 hours for approximately 2-7 days for surgical patients and approximately 5 days for parturients

    Drug: Atenativ

Interventions

06

What researchers measure

Primary outcomes

  1. Thrombotic event incidence

    The primary objective of this study is to assess the incidence of the composite of TEs and TEEs in patients with congenital antithrombin deficiency under cover of Atenativ for surgical procedures or parturition

    Time frame: Up to day 30 post treatment initiation

Secondary outcomes

  1. Single dose Pharmacokinetics of Atenativ: Area under the curve (AUCnorm(0-∞))

    Assess the area under the curve (AUCnorm(0-∞)) of Atenativ in patients with congenital antithrombin deficiency

    Time frame: Up to day 14 post PK infusion

  2. Single dose Pharmacokinetics of Atenativ: Maximum plasma concentration (Cmax)

    Assess the maximum plasma concentration (Cmax) after a single dose of Atenativ in patients with congenital antithrombin deficiency

    Time frame: Before first infusion, 20 minutes, 1 hour, 3 hours, 8 hrs, 1 day, 2 days, 3, days, 4 days, 5 days, 6 days, 7 days, 8 days, 10 days, 12 days and 14 days post-infusion

  3. Single dose Pharmacokinetics of Atenativ: Half-life (t1/2)

    Assess the half-life (t1/2) after a single dose of Atenativ in patients with congenital antithrombin deficiency

    Time frame: Before first infusion, 20 minutes, 1 hour, 3 hours, 8 hrs, 1 day, 2 days, 3, days, 4 days, 5 days, 6 days, 7 days, 8 days, 10 days, 12 days and 14 days post-infusion

  4. Single dose Pharmacokinetics of Atenativ: Mean residence time (MRT)

    Assess the mean residence time (MRT) after a single dose of Atenativ in patients with congenital antithrombin deficiency

    Time frame: Before first infusion, 20 minutes, 1 hour, 3 hours, 8 hrs, 1 day, 2 days, 3, days, 4 days, 5 days, 6 days, 7 days, 8 days, 10 days, 12 days and 14 days post-infusion

  5. Single dose Pharmacokinetics of Atenativ: Clearance (CL)

    Assess the clearance (CL) after a single dose of Atenativ in patients with congenital antithrombin deficiency

    Time frame: Before first infusion, 20 minutes, 1 hour, 3 hours, 8 hrs, 1 day, 2 days, 3, days, 4 days, 5 days, 6 days, 7 days, 8 days, 10 days, 12 days and 14 days post-infusion

  6. Single dose Pharmacokinetics of Atenativ: Incremental in vivo recovery (IVR)

    Assess the Incremental in vivo recovery after a single dose of Atenativ in patients with congenital antithrombin deficiency

    Time frame: Before first infusion, 20 minutes, 1 hour, 3 hours, 8 hrs, 1 day, 2 days, 3, days, 4 days, 5 days, 6 days, 7 days, 8 days, 10 days, 12 days and 14 days post-infusion

  7. Single dose Pharmacokinetics of Atenativ: Volume of distribution at steady state (Vss)

    Assess the volume of distribution at steady state (Vss) after a single dose of Atenativ in patients with congenital antithrombin deficiency

    Time frame: Before first infusion, 20 minutes, 1 hour, 3 hours, 8 hrs, 1 day, 2 days, 3, days, 4 days, 5 days, 6 days, 7 days, 8 days, 10 days, 12 days and 14 days post-infusion

  8. Single dose Pharmacokinetics of Atenativ: Maximum Plasma Concentration (Tmax)

    Assess the time to reach Maximum Plasma Concentration (Tmax) after a single dose of Atenativ in patients with congenital antithrombin deficiency

    Time frame: Before first infusion, 20 minutes, 1 hour, 3 hours, 8 hrs, 1 day, 2 days, 3, days, 4 days, 5 days, 6 days, 7 days, 8 days, 10 days, 12 days and 14 days post-infusion

  9. 10. Coagulation parameters: Activated partial thromboplastin time [aPTT]

    Assess activated partial thromboplastin time \[aPTT\] in patients with congenital antithrombin deficiency undergoing surgical procedures or parturition

    Time frame: Up to day 7 post treatment initiation

  10. Coagulation parameters: Prothrombin time [PT]

    Assess prothrombin time \[PT\] in patients with congenital antithrombin deficiency undergoing surgical procedures or parturition

    Time frame: Up to day 7 post treatment initiation

  11. Coagulation parameters: International normalised ratio [INR]

    Assess international normalised ratio \[INR\] in patients with congenital antithrombin deficiency undergoing surgical procedures or parturition

    Time frame: Up to day 7 post treatment initiation

  12. Coagulation parameters: Fibrinogen level

    Assess fibrinogen in patients with congenital antithrombin deficiency undergoing surgical procedures or parturition

    Time frame: Up to day 7 post treatment initiation

  13. Safety and tolerability: Number of adverse events (AEs)

    Number of adverse events (AEs) following treatment with Atenativ in patients with congenital antithrombin deficiency

    Time frame: Up to day 30 post treatment initiation

07

Study locations

30 of 30 sites recruiting
  • Georgetown University Hospital
    Washington D.C., District of Columbia 20057, United States
    Recruiting
  • University of Miami, Miller School of Medicine
    Miami, Florida 33124, United States
    Recruiting
  • Bleeding and Clotting Disorders Institute
    Peoria, Illinois 61615, United States
    Recruiting
  • Weill Cornell Medicine, New York Presbyterian Hospital
    New York, New York 10065, United States
    Recruiting
  • Duke University School of Medicine, Division of Hematology
    Durham, North Carolina 27708, United States
    Recruiting
  • Yeolyan Hematology and Oncology Centre
    Yerevan, Armenia
    Recruiting
  • Medizinische Universität Wien. Universitätsklinik für Innere Medizin Klinische Abteilung für Hämatologie und Hämostaseologie
    Vienna, Austria
    Recruiting
  • Centre for Thrombosis and Haemaostasis Nemocnice
    Nymburk, Czechia
    Recruiting
  • Centre de Référence de l'Hémophilie Unité d'Hémostase Clinique Hôpital Cardiologique Louis Pradel
    Bron, France
    Recruiting
  • University Hospital of Reims
    Reims, France
    Recruiting
  • Centre Hospitalier Universitaire de Rouen (CHU de Rouen) - Centre de Traitement des Maladies Hemorragiques (CRTH) (Centre d'Hemophiles)
    Rouen, France
    Recruiting
  • Aversi Clinic
    Tbilisi, Georgia
    Recruiting
  • Vivantes Klinikum Friedrichshain Klinik für Angiologie Hämostaseologie
    Berlin, Germany
    Recruiting
  • UKB Bonn Institut für Experimentelle Hämatologie und Transfusionsmedizin
    Bonn, Germany
    Recruiting
  • Gerinnungszentrum Rhein-Ruhr
    Duisburg, Germany
    Recruiting
  • University of Debrecen, Medical and Health Science Centre
    Debrecen, Hungary
    Recruiting
  • Rabin Medical Centre, Institute of Haematology
    Petah Tikva, Israel
    Recruiting
  • Sheba Medical Centre
    Ramat Gan, Israel
    Recruiting
  • Unita Strutturale Complessa di Immunoematologia e Medicina Trasfusionale -Dipartimento Interaziendale di Medicina Trasfusionale ed Ematologia - ASST Papa Giovanni XXIII ematologia Piazza OMS, 1
    Bergamo, 24127, Italy
    Recruiting
  • Universita degli Studi di Milano - IRCCS Ospedale Maggiore Policlinico - Centro Emofilia e Trombosi Angelo Bianchi Bonomi
    Milan, Italy
    Recruiting
  • University of Padua Medical School
    Padua, Italy
    Recruiting
  • Fondazione Policlinico Universitario Agostino Gemelli IRCCS
    Roma, Italy
    Recruiting
  • Emergency County Hospital Craiova
    Craiova, Romania
    Recruiting
  • Clinical Center of Serbia
    Belgrade, Serbia
    Recruiting
  • Central University Hospital of Asturias
    Oviedo, Principality of Asturias 33011, Spain
    Recruiting
  • Hospital Universitario La Paz
    Madrid, 28046, Spain
    Recruiting
  • Hospital Universitario Morales Meseguer
    Murcia, Spain
    Recruiting
  • Ourense University Hospital
    Ourense, 32005, Spain
    Recruiting
  • Royal-free Hospital-Katherine Dormandy Haemophilia and Thrombosis Centre
    London, United Kingdom
    Recruiting
  • St. Thomas Hospital, Guy's and St. Thomas' NHS Foundation Trust
    London, United Kingdom
    Recruiting
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Updates

1 registry update since Sep 25, 2026
Sites
8 sites added, 8 sites removed
Show 8 added (4 United States, 1 Austria, 1 Czechia, 1 Germany, 1 United Kingdom)
  • Georgetown University Hospital · Washington D.C., United States
  • University of Miami, Miller School of Medicine · Miami, United States
  • Weill Cornell Medicine, New York Presbyterian Hospital · New York, United States
  • Duke University School of Medicine, Division of Hematology · Durham, United States
  • Medizinische Universität Wien. Universitätsklinik für Innere Medizin Klinische Abteilung für Hämatologie und Hämostaseologie · Vienna, Austria
  • Centre for Thrombosis and Haemaostasis Nemocnice · Nymburk, Czechia
  • Vivantes Klinikum Friedrichshain Klinik für Angiologie Hämostaseologie · Berlin, Germany
  • St. Thomas Hospital, Guy's and St. Thomas' NHS Foundation Trust · London, United Kingdom
Show 8 removed
  • Georgetown University · Washington D.C., United States
  • University of Miami · Miami, United States
  • Weill Cornell Medicine · New York, United States
  • Duke University · Durham, United States
  • Universitätsklinik für Innere Medizin Klinische Abteilung für Hämatologie und Hämostaseologie · Vienna, Austria
  • Centre for Thrombosis and Haemaostasis · Nymburk, Czechia
  • Klinik fur Angiologie Hamostaseologie Haus 12 A Gerinnungssprechstunde · Berlin, Germany
  • St. Thomas Hospital · London, United Kingdom
Sep 28, 2026
Show all 1 update
  1. Sep 28, 2026
    8 sites added, 8 sites removed
    Show 8 added (4 United States, 1 Austria, 1 Czechia, 1 Germany, 1 United Kingdom)
    • Georgetown University Hospital · Washington D.C., United States
    • University of Miami, Miller School of Medicine · Miami, United States
    • Weill Cornell Medicine, New York Presbyterian Hospital · New York, United States
    • Duke University School of Medicine, Division of Hematology · Durham, United States
    • Medizinische Universität Wien. Universitätsklinik für Innere Medizin Klinische Abteilung für Hämatologie und Hämostaseologie · Vienna, Austria
    • Centre for Thrombosis and Haemaostasis Nemocnice · Nymburk, Czechia
    • Vivantes Klinikum Friedrichshain Klinik für Angiologie Hämostaseologie · Berlin, Germany
    • St. Thomas Hospital, Guy's and St. Thomas' NHS Foundation Trust · London, United Kingdom
    Show 8 removed
    • Georgetown University · Washington D.C., United States
    • University of Miami · Miami, United States
    • Weill Cornell Medicine · New York, United States
    • Duke University · Durham, United States
    • Universitätsklinik für Innere Medizin Klinische Abteilung für Hämatologie und Hämostaseologie · Vienna, Austria
    • Centre for Thrombosis and Haemaostasis · Nymburk, Czechia
    • Klinik fur Angiologie Hamostaseologie Haus 12 A Gerinnungssprechstunde · Berlin, Germany
    • St. Thomas Hospital · London, United Kingdom
    + 1 other change: verification date

From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗

10

Registry details

Key details

Study ID
NCT04918173
Lead sponsor
Octapharma
Responsible party
Sponsor
First posted
Jun 8, 2021
Start date
Jul 1, 2022
Primary completion
Dec 1, 2026 (estimated)
Completion
Dec 1, 2026 (estimated)
Last update
Sep 28, 2026

Study contacts

Sigurd Knaub
Contact
Sigurd.Knaub@octapharma.com
+41554512141

Oversight

FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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Studies of the drug tested here: Antithrombin III

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