ClinicalTrials.gg
RecruitingNCT04398628Updated Aug 17, 2026

ATHN Transcends: A Natural History Study of Non-Neoplastic Hematologic Disorders

An observational study in Hematologic Disorder, Bleeding Disorder and Connective Tissue Disorder, sponsored by American Thrombosis and Hemostasis Network. Recruiting at 76 sites in United States. Per ClinicalTrials.gov, last updated 2026-08-17.

Sponsored by American Thrombosis and Hemostasis Network · Observational

From the registry’s dates

  • Started Sep 2020; still recruiting 6 years 1 month later.
Study type
Observational
Model
Cohort
Time perspective
Prospective
Enrollment
3,000
Sex
All
01

Study summary

In parallel with the growth of ATHN's clinical studies, the number of new therapies for all blood disorders is increasing significantly. Some of the recently FDA-approved therapies for congenital and acquired hematologic conditions have not yet demonstrated long-term safety and effectiveness beyond the pivotal trials that led to their approval. In addition, results from well controlled, pivotal studies often cannot be replicated once a therapy has been approved for general use.2,3,4,5

In 2019 alone, the FDA has issued approvals for 24 new therapies for congenital and acquired hematologic conditions.6 In addition, almost 10,000 new studies for hematologic diseases are currently registered on www.clinicaltrials.gov.7

With this increase in potential new therapies possible, it is imperative that clinicians and clinical researchers in the field of non-neoplastic hematology have a uniform, secure, unbiased, and enduring method to collect long-term safety and efficacy data. As emphasized in a recently published review, accurate, uniform and quality national data collection is critical in clinical research, particularly for longitudinal cohort studies covering a lifetime of biologic risk.8

Read the detailed description

This is a longitudinal, natural history observational cohort study being conducted at approximately 150 ATHN-affiliated sites with a target accrual of 3,000 participants. Participants will be followed for a minimum of 15 years on an assigned arm within a cohort; however, arm or module participation may last longer, and participants will continue participation in the arm or module for its duration. Harmonized data elements will be collected at the time of enrollment, semi-annually (every 6 months), annually, ad hoc, and as defined by the terms of individual arms and modules. Data will be collected for participants enrolled in cohort-specific arms and modules.

Each participant will be assigned to a single cohort: Hemophilia, von Willebrand Disease, Congenital Platelet Disorders, Rare Disorders, Bleeding Not Otherwise Specified (NOS), Thrombosis/Thrombophilia, or Non-Neoplastic Hematologic Conditions.

Study arms and study modules are developed to advance the exploration of blood disorders disease specific insights by ATHN and its partners. Arms may branch off into product-specific data collection via Modules to be collected during the study, in conjunction with planned study assessments.

ATHN Transcends

Co- Principal Investigators:

Tammuella Chrisentery-Singleton, MD Ochsner Clinic Foundation American Thrombosis and Hemostasis Network

Michael Recht, MD, PhD, MBA Yale University School of Medicine National Bleeding Disorders Foundation

PUPs Arm

Principal Investigator:

Shannon Carpenter, MD, MS University of Missouri Kansas City School of Medicine Children's Mercy Hospital

ALTUVIIO Module

Principal Investigator:

Shannon Carpenter, MD, MS University of Missouri Kansas City School of Medicine Children's Mercy Hospital

INHIBIT Module

Principal Investigator:

Nicoletta Machin DO, MS Hemophilia Center of Western Pennsylvania University of Pittsburgh Medical Center

Hemophilia Natural History Arm

Principal Investigator:

Fernando Corrales-Medina, MD, FAAP University of Miami-Comprehensive Hemophilia Treatment Center University of Miami-Miller School of Medicine

Rebinyn Module

Co-Principal Investigators:

Lauren Amos, MD University of Missouri Kansas City School of Medicine Children's Mercy Hospital

Guy Young, MD University of Southern California Children's Hospital Los Angeles

Distress Module

Principal Investigator:

Tammuella Chrisentery-Singleton, MD Ochsner Clinic Foundation American Thrombosis and Hemostasis Network

Hemlibra Module

Principal Investigator:

Fernando Corrales-Medina, MD, FAAP University of Miami-Comprehensive Hemophilia Treatment Center University of Miami-Miller School of Medicine

Hemophilia Gene Therapy Outcomes Arm:

Co-Principal Investigators:

Janice M. Staber, MD Iowa Hemophilia and Thrombosis Center University of Iowa Stead Family Children's Hospital

Ulrike M. Reiss, MD Hemophilia Treatment Center St. Jude's Children's Research Hospital

HEMGENIX Module

Co-Principal Investigators:

Janice M. Staber, MD Iowa Hemophilia and Thrombosis Center University of Iowa Stead Family Children's Hospital

Ulrike M. Reiss, MD Hemophilia Treatment Center, St. Jude's Children's Research Hospital

Severe VWD Natural History Arm:

Co-Principal Investigators:

Robert F. Sidonio, Jr., MD, MSc Aflac Cancer and Blood Disorders Center, Hemophilia of Georgia Center for Bleeding and Clotting Disorders

Angela C. Weyand, MD C.S. Mott Children's Hospital, University of Michigan Medical School, Ann Arbor

Congenital Platelet Disorders Natural History Arm:

Principal Investigator Sanjay Ahuja, MD Innovative Hematology, Indiana Hemophilia \& Thrombosis Center

Glanzmann Thrombasthenia Module:

Co-Principal Investigators:

Divya Citla-Sridhar, MD University of Arkansas for Medical Sciences Arkansas Children's Hospital

Meera Chitlur, MD Central Michigan University, Children's Hospital of Michigan

Hemophilia Cohort

This cohort includes three Arms and six Modules:

Previously Untreated Patients (PUPs) Arm This is a pediatric focused Arm of PUPs with hemophilia A or B of any severity.

Efanestoctocog alfa (ALTUVIIIO®) Module The purpose is to investigate the safety, tolerability, and effectiveness of efanesoctocog alfa (ALTUVIIIO®) in PUPs with severe hemophilia A.

INHIBIT Module This is an observational study assessing the rate of inhibitor formation in young children with severe hemophilia A in the current treatment era.

Hemophilia Natural History Arm This Arm is investigating the safety, effectiveness, and practice of treatment for people with hemophilia.

Emicizumab (Hemlibra®) Module All participants treated with Hemlibra® are eligible to participate.

Distress Module Participants with Congenital Hemophilia A or B, 18 years of age or older, will be followed longitudinally for 2 years or from time of enrollment for a total planned study duration of 3 years

Nonacog beta pegol (Rebinyn®) Module The Rebinyn® Module is a prospective study in hemophilia B participants without inhibitors.

Hemophilia Gene Therapy Outcomes Arm This Arm is investigating the safety and effectiveness of gene therapy in people with hemophilia.

Etranacogene dezaparvovec (HEMGENIX®) Module This is an observational study to characterize the effectiveness and safety of HEMGENIX® in participants with hemophilia B.

Congenital Platelet Disorders (CPD) Natural History Arm:

The CPD Arm is investigating the natural history of the safety and efficacy of hemostatic therapies (such as platelet transfusions, desmopressin, antifibrinolytics, recombinant factor VIIa) in the prevention or treatment of bleeding events (on demand, surgery, prophylaxis) in adult and pediatric participants with inherited congenital platelet disorders..

Glanzmann Thrombasthenia (GT) Module:

This Module is a study of bleeding symptoms, treatments, and treatment outcomes in patients with Glanzmann thrombasthenia.

Von Willebrand Disease Cohort No arms or modules open at this time.

Rare Disorders Cohort No arms or modules open at this time.

Bleeding NOS No arms or modules open at this time.

Thrombosis/Thrombophilia No arms or modules open at this time.

Non-Neoplastic Hematologic Conditions No arms or modules open at this time.

02

Conditions studied

  • Hematologic Disorder
  • Bleeding Disorder
  • Connective Tissue Disorder
  • Hemophilia
  • Thrombosis
  • Von Willebrand Diseases
  • Thrombophilia
  • Rare Bleeding Disorder
  • Platelet Disorder
  • Factor IX Deficiency
  • Factor VIII Deficiency
  • Thalassemia
  • Sickle Cell Disease
03

In context

Hematologic Diseases

609 studies on the registry are indexed under Hematologic Diseases; 108 are open to participants now.

This study's planned enrollment of 3,000 is above the median of 250 across 127 observational studies indexed under Hematologic Diseases.

Browse Hematologic Diseases studies →

Lead sponsor

American Thrombosis and Hemostasis Network is the lead sponsor of 8 studies on the registry; 3 are open to participants now.

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

04

Who can participate

Ages eligible
Child (0–17), Adult (18–64), Older adult (65+)
Sexes eligible
All
Accepts healthy volunteers
No
Sampling method
Probability sample

Study population

This is a real-world study in which participants with congenital or acquired blood disorders will be enrolled.

Eligibility criteria

Participants who meet the following inclusion criteria and none of the exclusion criteria are eligible for enrollment in one of the open disease-specific arms.

Inclusion Criteria:

  1. Any age
  2. Having a congenital or acquired blood disorder; or
  3. Having a bleeding phenotype as indicated by an age adjusted abnormal ISTH Bleeding Assessment Tool score with an unknown diagnosis; or
  4. Connective tissue disorder with bleeding tendency as indicated by an age adjusted abnormal ISTH Bleeding Assessment Tool score.
  5. Eligible for a currently active disease-specific arm.
  6. Concurrent enrollment in the ATHNdataset or current ATHNdataset participant.

Exclusion Criteria:

1. Does not qualify for inclusion in a currently activedisease-specific arm; participants may be eligible to enroll as future cohorts and arms are activated; 2. Unable to give or assent 3. Unwilling to perform study procedures

Cohort Participant Selection

Each participant is to be enrolled in the cohort for which they qualify as defined below.

Hemophilia Cohort

Inclusion Criteria:

Participants who meet any of the following inclusion criteria are eligible for enrollment into this cohort:

  1. Factor VIII or factor IX activity \<50%, without another explanation for low clotting factor other than congenital hemophilia or being a known carrier for congenital hemophilia; OR
  2. Carrier for congenital hemophilia with a factor VIII >=50% or factor IX activity >=50% with or without a bleeding phenotype as indicated by an ISTH Bleeding Assessment Tool score of ≥4 for adult males, ≥6 for adult females, or ≥3 for children younger than 18 years OR
  3. Known congenital hemophilia that have a factor level >50% after receiving vector, OR 4. Acquired hemophilia.

Exclusion Criteria:

None

Von Willebrand Disease Cohort

Inclusion Criteria:

Participants who meet the following inclusion criteria are eligible for enrollment into this cohort:

1. Meeting the definition of VWD or low VWF per most recent international guidelines

Exclusion Criteria:

None

Congenital Disorders Cohort

Inclusion Criteria:

Participants who meet the following inclusion criteria are eligible for enrollment into this cohort:

  1. Abnormalities of platelet function a. Glanzmann thrombasthenia (GPIIb or GPIIIa) b. Bernard-Soulier syndrome (GPIbalpha, GPIbbeta, or GPIX)
  2. Abnormalities of platelet granules
  3. Abnormalities of platelet signal transduction
  4. Abnormalities of platelet secretion
  5. Collagen Receptor Defect
  6. ADP Receptor Defect
  7. Thromboxane Receptor Defect
  8. Giant Platelet Disorder
  9. Abnormalities in platelet aggregation testing due to another or unknown cause (not drug related)

Exclusion Criteria:

1. Platelet disorders secondary to medications or other substances

Rare Disorders Cohort

Inclusion Criteria:

Participants who meet the following inclusion criteria are eligible for enrollment into this cohort:

1. Have an established Rare Coagulation Disorder (RCD) diagnosis of one of the following:

  1. PAI-1 deficiency
  2. Factor I, II, V, VII, X, XI, XIII deficiencies
  3. Combined FV and FVIII deficiency
  4. Plasminogen deficiency
  5. Decreased tissue plasminogen activator
  6. Afibrinogenemia/hypofibrinogenemia/dysfibrinogenemia
  7. Thrombotic Thrombocytopenia Purpura or Congenital Hemolytic Uremic Syndrome
  8. Wiskott-Aldrich
  9. Methylenetetrahydrofolate Reductase Deficiency

Exclusion Criteria:

None

Bleeding NOS Cohort

Inclusion Criteria:

Participants who meet the following inclusion criteria are eligible for enrollment into this cohort:

  1. Have a bleeding phenotype as indicated by an ISTH Bleeding Assessment Tool score of ≥4 for adult males, ≥6 for adult females, or ≥3 for children younger than 18 years with an unknown diagnosis, OR
  2. Connective tissue disorder with bleeding tendency as indicated by an ISTH Bleeding Assessment Tool score of ≥4 for adult males, ≥6 for adult females, or ≥3 for children younger than 18 years.

Exclusion Criteria:

None

Thrombosis/Thrombophilia Cohort

Inclusion Criteria

Participants who meet the following inclusion criteria are eligible for enrollment into this cohort:

1. Have a prior history of arterial or venous thrombosis. 2. Participants with a known congenital or acquired thrombophilia with or without thrombosis.

a. Common congenital thrombophilias: i. Protein C deficiency ii. Protein S deficiency iii. Antithrombin deficiency iv. Factor V Leiden v. Prothrombin gene mutation b. Rare genetic factors i. Hyperhomocysteinemia c. Indeterminate genetic factors i. Elevated factor VIII ii. Elevated factor IX iii. Elevated factor XI iv. Elevated lipoprotein (a) d. Acquired thrombophilias i. Lupus anticoagulant ii. Anti-cardiolipin antibodies/Beta2 glycoprotein antibodies iii. Antiphospholipid syndrome

Exclusion Criteria Acquired thrombophilia secondary to medications ( pills or hormone replacement therapy), overweight or obesity, smoking, cancer, pregnancy, surgery, injury, prolonged inactivity/bedrest, heart failure, inflammatory bowel disease, or kidney disease

Non-Neoplastic Hematologic Conditions Cohort

Inclusion Criteria

Participants who meet the following inclusion criteria are eligible for enrollment into this cohort:

1. Having any congenital or acquired non-neoplastic hematologic disorder not included in any other cohort

Exclusion Criteria None

Arm/Module Participant Selection

Previously Untreated Patients Arm

Inclusion Criteria:

  1. Diagnosis of congenital hemophilia A (FVIII \<40%) or hemophilia B (FIX \<40% or below lower limit for age)
  2. Age \<18 years at time of enrollment
  3. Parent or authorized guardian or legally authorized representative (LAR) can provide informed consent
  4. Care established at one of the ATHN Transcends participating HTCs
  5. Clotting Factor Concentrate (CFC) exposure, fresh frozen plasma (FFP), cryoprecipitate, and single donor platelets \<3 exposure days (ED)

Exclusion Criteria

  1. Concomitant diagnosis with another bleeding disorder
  2. History of a confirmed, positive inhibitor

INHIBIT Module

Inclusion Criteria:

1. Diagnosis of severe factor VIII deficiency with baseline factor VIII level \<1% 2. Initiating or plan to initiate prophylaxis with emicizumab or factor replacement 3. Factor concentrate exposure, Fresh Frozen Plasma (FFP), cryoprecipitate, and single donor platelets ≤3 EDs 4. ≤5 years of age

Exclusion Criteria

  1. Concomitant diagnosis with bleeding disorder other than hemophilia A
  2. Immune disorder
  3. Previous history or presence of factor VIII inhibitor. A confirmed, positive inhibitor is defined as two consecutive positive inhibitor titers (≥ 0.6 BU) that result in changes in treatment recommendations.

Efanesoctocog alfa (ALTUVIIIO®) Module

Inclusion criteria:

  1. Ability of the potential participant's legally authorized representative (e.g., their parent or legal guardian) to understand the purpose and risks of the study and provide signed and dated informed consent and authorization to use confidential health information in accordance with national and local participant privacy regulation.
  2. People with severe HA with a baseline FVIII activity of less than 1%. (While inclusion for participation in ATHN Transcends lists \<5% FVIII activity, this proposed module will limit enrollment to people with FVIII activity levels of \<1%.) Other severities may be included per ATHN Transcends PI approval.
  3. \<18 years of age.
  4. No history of a confirmed, positive FVIII inhibitor.
  5. Sex assigned at birth of male, female, or intersex.
  6. Participants should have no more than three (3) exposure days of blood products (fresh frozen plasma, cryoprecipitate, or platelets), no more than three (3) doses of any FVIII concentrate other than efanesoctocog alfa, and up to three (3) doses of efanesoctocog alfa prior to enrollment.
  7. Site PI confirmed all inclusion criteria has been met.

Exclusion criteria:

  1. Not meeting all the inclusion criteria; confirmed by site PI.
  2. Any exposure to blood products or FVIII replacement products except as described in the inclusion criteria.
  3. History of positive inhibitor testing.
  4. History of reactions associated with efanesoctocog alfa administration.
  5. Other coagulation disorder(s) in addition to Hemophilia A.
  6. Any concurrent major disease such as cancer that, in the opinion of the investigator, would make the participant unsuitable for enrollment.
  7. Concurrent systemic treatment with chemotherapy and/or other medications. Use of for the treatment of asthma or management of acute allergic or otherwise life-threatening episodes is allowed except for systemic corticosteroid treatment given to children daily or on an alternate day schedule at > 2 mg/kg/day of prednisone or its equivalent or > 20 mg/day if the duration is longer than 14 days.
  8. Enrollment in a concurrent clinical interventional drug study.
  9. Intake of an Medicinal Product within three (3) months prior to inclusion in this study.
  10. Inability to comply with study requirements.
  11. Other, unspecified reasons that, in the investigator's opinion, make the participant unsuitable for enrollment.

Hemophilia Natural History Arm

Inclusion Criteria

  1. Congenital or acquired hemophilia A or B of any severity with or without inhibitors receiving a current therapy, a non-factor product, or for whom use of a non-factor product is a possibility, OR
  2. Females of any age, with confirmed congenital hemophilia A or B carrier status with genetic mutational analysis and any factor level.

Exclusion Criteria

  1. Presence of any known bleeding disorder other than congenital hemophilia A or B
  2. Presence of concurrent hemophilia and a second hemostatic defect (low von Willebrand Factor (vWF) without vWD diagnosis is not excluded)
  3. Unable or unwilling to comply with the study arm protocol.

Nonacog beta pegol (Rebinyn®) Module

Inclusion Criteria:

  1. Has provided signed written consent for the nonacog beta pegol (Rebinyn®)Module before any study-related activities.
  2. Male participants, at any age with hemophilia B, naïve or minimally exposed (up to 3 EDs) to nonacog beta pegol treatment at time of study enrollment. Additional doses may be allowable per ATHN Transcends PI approval.
  3. Decision to initiate continuous prophylaxis treatment with commercially available nonacog beta pegol has been made by the participant(s)/Legally Authorized Representative(s) (LAR(s)) and the treating physician before and independently from the decision to include the participant in this study.

Exclusion Criteria:

  1. Previous participation in this study. Participation is defined as having given informed consent in this study.
  2. Mental incapacity, unwillingness or language barriers precluding adequate understanding or cooperation, including a diagnosis or suspicion of attention deficit hyperactivity disorder (ADHD) or autism spectrum disorder (ASD) per the discretion of the Principal Investigator.
  3. Known or suspected hypersensitivity to nonacog beta pegol or related products.
  4. Clinical suspicion or presence of FIX inhibitor at time of inclusion.
  5. Inability or unwillingness to undergo neurological assessment/structured developmental history.

Emicizumab (Hemlibra®) Module

Inclusion Criteria:

  1. Participant currently treated with emicizumab (Hemlibra®)
  2. Currently enrolled in the Hemophilia Natural History Arm of ATHN Transcends

Exclusion Criteria:

1. Unable or unwilling to comply with the protocol

Distress Module

Inclusion Criteria:

  1. Congenital hemophilia A or B of any severity with or without inhibitors receiving a current therapy, a non-factor product, or for whom use of a non-factor product is a possibility
  2. Age 18 years of age or older
  3. English speaking

Exclusion Criteria:

  1. Presence of any known bleeding disorder other than congenital hemophilia A or B;
  2. Presence of concurrent hemophilia and a second hemostatic defect (low von Willebrand Factor (vWF) without vWD diagnosis is not excluded); and
  3. Unable or unwilling to comply with the study arm protocol

Hemophilia Gene Therapy Outcomes Arm

Inclusion Criteria

  1. Hemophilia A or B of any severity with or without inhibitors having received or will receive a hemophilia gene transfer product in the next 6 months.
  2. Age 18 years and older.
  3. Able to give informed consent.

Exclusion Criteria None

Etranacogene dezaparvovec (HEMGENIX®) Module

Inclusion Criteria:

Etranacogene dezaparvovec (HEMGENIX®) Cohort

  1. Age 18 years of age or older
  2. Treatment with commercial etranacogene dezaparvovec (HEMGENIX®)
  3. Have provided signed written informed consent within 3 months before or within 6 months after etranacogene dezaparvovec (HEMGENIX®) treatment, or within 6 months of when the study is initiated at the treating site.

FIX Prophylaxis Cohort

  1. Age 18 years of age or older
  2. Treatment with FIX prophylaxis therapy
  3. Has provided signed written consent at any time for ATHN Transcends Study

Exclusion Criteria, both cohorts:

1. Have been treated with etranacogene dezaparvovec in a clinical trial prior to commercial availability. These patients are still eligible for enrollment in the Gene Therapy Outcomes Arm, and their data may be collected for separate analysis.

Congenital Platelet Disorders Arm

Inclusion Criteria

  1. Platelet adhesion defect

    1. Bernard Soulier syndrome (Defective GPIb-IX-V receptor, impaired adhesion to vWF)
    2. Velocardio-facial syndrome/DiGeorge syndrome (Defective GPIb-IX-V receptor)
    3. Platelet type vWD (Defective GPIb-IX-V, gain of function interaction between vWF-GP1bα)
  2. Platelet aggregation defect

    1. Glanzmann thrombasthenia (Defective integrin αIIbβ3 (GPIIb/IIIa)
    2. Platelet aggregation defect, NOS
  3. Agonist receptor defects

    1. Epinephrine
    2. ADP
    3. Collagen
    4. Thromboxane A2
  4. Platelet signaling defects

    1. Cyclooxygenase deficiency (PTGS1 mutation)
    2. Phospholipase A2 deficiency
    3. Thromboxane synthase deficiency (TBXAS1 mutation)
    4. G protein activation defect (GNAS mutation)
    5. Scott syndrome (defect in phosphatidyl serine translocation)
  5. Platelet Granule disorders

    1. Dense granule storage pool disorder

      • Hermansky Pudlak syndrome
      • Chediak Higashi syndrome
      • Griscelli syndrome
    2. Alpha granule storage pool disorder

      • Grey platelet syndrome
      • Arthrogryposis-Renal Dysfunction-Cholestasis (ARC) syndrome
      • Quebec platelet disorder
      • Paris-Trousseau syndrome
    3. Combined alpha delta granule deficiency
  6. Platelet cytoskeletal structure defects

    1. Wiskott Aldrich syndrome
    2. MYH9 associated disorders (myosin heavy chain)

      • May Hegglin syndrome
      • Fechtner syndrome
      • Sebastian syndrome
      • Epstein syndrome
    3. Other mutations

      • FLNA mutations (Filamin)
      • DIAPH1 (Actin and microtubules)
      • ACTN1 (alpha actinin)
      • TPM4 (tropomyosin)
      • TUBB1 (beta tubulin)
  7. Other Congenital thrombocytopenias

    1. Familial platelet disorders and predisposition to AML (RUNX1)
    2. X linked thrombocytopenia with dyserythropoiesis (GATA1)
    3. Congenital amegakaryocytic thrombocytopenia (MPL)

Exclusion Criteria

  1. Diagnosis of von Willebrand Disease (Meeting the definition of vWD or low vWF per most recent international guidelines)
  2. Diagnosis of Hemophilia A or Hemophilia B (Factor VIII or IX ≤ 40%)

Glanzmann Thrombasthenia (GT) Module

Inclusion Criteria

  1. Participant has signed the informed consent/assent form
  2. Participant has flow cytometry or aggregometry or genetics confirmed GT
  3. Participant is willing to perform study procedures, including daily bleed tracking for 3 months and further if requested
  4. Participants are 2 years or older at time of consent

Exclusion Criteria None

Terms in these criteria, in plain language(8)

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.

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.

Platelets

Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

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.

Clinically significant

Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

Immunosuppression

A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.

Read whether the line is about a condition or about medicines, and which medicines and doses it means.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

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

Observational model
Cohort
Time perspective
Prospective
Enrollment
3,000 participants (estimated)
Patient registry
No
Biospecimen retention
Samples with dna

Groups and cohorts

  • Hemophilia

    This cohort includes three Arms and six Modules: Previously Untreated Patients (PUPs) Arm Efanestoctocog alfa (ALTUVIIIO®) Module INHIBIT Module Hemophilia Natural History Arm Emicizumab (Hemlibra®) Module Nonacog beta pegol (Rebinyn®)Module Distress Module Hemophilia Gene Therapy Outcomes Arm Etranacogene dezaparvovec (HEMGENIX®) Module

  • Congenital Platelet Disorders

    This cohort includes one Arm and Module: Congenital Platelet Disorders (CPD) Natural History Arm Glanzmann Thrombasthenia (GT) Module

  • Von Willebrand Disease

    No arms or modules

  • Rare Disorders

    No arms or modules

  • Bleeding NOS

    No arms or modules

  • Thrombosis/Thrombophilia

    No arms or modules

  • Non-Neoplastic Hematologic Conditions

    No arms or modules

06

What researchers measure

Primary outcomes

  1. To determine the safety of therapies used in the treatment of participants with congenital or acquired non-neoplastic, bleeding and clotting disorders and connective tissue disorders with bleeding tendency (blood disorders).

    Safety will be measured by those events in the European Safety Surveillance (EUHASS)1: 1. Allergic or other acute events 2. Treatment-emergent side effects of therapy 3. Transfusion transmitted infections 4. Inhibitor development 5. Thrombosis 6. Cardiovascular events 7. Malignancies 8. Neurological events 9. Death In addition to the modified EUHASS endpoints, the following events will be collected as adverse events of special interest (AESI): 1. The occurrence of thrombotic microangiopathies, injection site reactions and cases of potential drug-induced liver injury 2. The development of anti-drug antibodies, to be measured and confirmed, if feasible 3. Severe, unanticipated bleeding 4. Hospitalizations 5. Glomerulonephritis 6. Any arm or module-specific AESI as stated in their corresponding Safety Assessment section Additional safety events of interest may be collected.

    Time frame: 15 years

Secondary outcomes

  1. To establish a platform to support study arms and modules for participants with blood disorders.

    For each Arm, a brief set of data elements of interests will be developed and reported for study participants.

    Time frame: 15 years

  2. To describe medication dosing regimens in participants with blood disorders.

    This objective will be evaluated by: 1. Determining the number of participants who initiate and/or switch treatment with non-factor products and participants' reasons for initiating and/or switching treatment with non-factor products 2. Determining the number of participants who do not initiate treatment with non-factor products 3. Determining the number of participants who switch between different non-factor products and the participants' reasons for switching non-factor products 4. Determining the number of participants who discontinue treatment with non-factor products and participants' reasons for discontinuing treatment with non-factor products

    Time frame: 15 years

  3. To describe real-world effectiveness of therapies used for participants with blood disorders.

    1. Health care utilization as measured by number and type of visits and hospitalizations per year 2. Patient reported outcomes (PROs) as measured by the Patient Reported Outcomes Measurement Information System (PROMIS®) Profile 29/25/Parent Proxy, Global Adherence Rating (GAR) (ages 7 and older), CATCH, and EQ-5D5L

    Time frame: 15 years

  4. To grow and evolve the ATHN Transcends Biorepository for current and future research through the collection of biospecimens from participants enrolled on this protocol

    All participants have the option to provide consent to have specimens stored in the ATHN Transcends Biorepository. Samples will be collected as needed, including at the Baseline Visit, Annual Visit, and at Study Exit Visit (if not collected at your Annual Visit), as funding allows.

    Time frame: 15 years

  5. To describe bleeding events, changes in overall bleeding, and annualized bleeding rate (ABR) as measured by individual bleeding components.

    This objective will be calculated per ISTH Bleeding Assessment Tool (ISTH BAT), participant completed Treatment and Bleed log, and if applicable, a Pictorial Bleeding Assessment Chart (PBAC), for relevant diagnoses.

    Time frame: 15 years

07

Study locations

74 of 76 sites recruiting
  • Arizona Hemophilia and Thrombosis Treatment Center at Phoenix Children's Hospital
    Phoenix, Arizona 85016, United States
    Recruiting
  • Arkansas Center for Bleeding Disorders
    Little Rock, Arkansas 72202, United States
    Recruiting
  • Orthopaedic Institute for Children HTC
    Los Angeles, California 90007, United States
    Recruiting
  • Childrens Hospital Los Angeles
    Los Angeles, California 90027-6016, United States
    Recruiting
  • UCSF Benioff Children's Hospital Oakland
    Oakland, California 94610, United States
    Recruiting
  • University of California at Davis Hemophilia Treatment Center
    Sacramento, California 95817, United States
    Recruiting
  • Loma Linda Hemoglobinopathy and Inherited Bleeding Disorder Program
    San Bernardino, California 92408, United States
    Recruiting
    • Rosa Rivas · Contact909-651-1910
    • Akshat Jain, MD · Principal investigator
  • Hemophilia & Thrombosis Treatment Center at UC San Diego Health
    San Diego, California 92121, United States
    Recruiting
  • Rady Children's Hospital San Diego
    San Diego, California 92123, United States
    Recruiting
    • Jacqueline Limjoco, RN, BSN · Contactjlimjoco1@rchsd.org
    • Julie Jaffray, MD · Principal investigator
  • University of California, San Francisco Hemophilia & Thrombosis Center
    San Francisco, California 94143, United States
    Recruiting
  • Connecticut Children's Medical Center
    Hartford, Connecticut 06106, United States
    Recruiting
  • Yale Hemophilia Treatment Center
    New Haven, Connecticut 06520, United States
    Recruiting
    • Lia Louizos · ContactE.Louizos@yale.edu
    • Stephanie Prozora, MD · Principal investigator
  • Delaware Hemophilia Treatment Center
    Wilmington, Delaware 19801, United States
    Recruiting
  • Georgetown University
    Washington D.C., District of Columbia 20007, United States
    Recruiting
  • Children's National Hemophilia Center
    Washington D.C., District of Columbia 20010, United States
    Recruiting
  • University of Florida Hemophilia Treatment Center
    Gainesville, Florida 32610, United States
    Recruiting
  • University of Miami Comprehensive Hemophilia Treatment Center
    Miami, Florida 33136, United States
    Recruiting
    • Leandro Pisani · ContactLFP34@miami.edu
    • Fernando Corrales-Medina, MD · Principal investigator
  • University of Miami Hospital and Clinics
    Miami, Florida 33136, United States
    Recruiting
    • Leandro Pisani · Contactlfp34@miami.edu · 305-243-6925
    • Fernando Corrales-Medina, MD · Principal investigator
  • Arnold Palmer Hospital for Children - The Haley Center for Children's Cancer and Blood Disorders
    Orlando, Florida 32806, United States
    Not yet recruiting
  • Johns Hopkins All Children's Hospital
    St. Petersburg, Florida 33701, United States
    Recruiting
    • Dawn Harrison, FNP · Contactdharr172@jhmi.edu
    • Irmel Ayala, MD · Principal investigator
  • St. Joseph's Hospital Center for Bleeding & Clotting Disorders
    Tampa, Florida 33607, United States
    Recruiting
  • University of South Florida - Adult
    Tampa, Florida 33612, United States
    Recruiting
    • Bradley Fletcher, MD · Contactbsfletcher@usf.edu · 813-974-9452
    • Bradley Fletcher, MD · Principal investigator
  • Comprehensive Bleeding Disorders Center at Emory University and Children's Healthcare of Atlanta
    Atlanta, Georgia 30308, United States
    Recruiting
    • Gina Aulisio · Contactgina.aulisio@emory.edu · 404-778-7062
    • Christine Kempton, MD · Principal investigator
  • Emory/Children's Health Care of Atlanta
    Atlanta, Georgia 30322, United States
    Recruiting
    • Simone Henry · Contactshenry@emory.edu
    • Robert Sidonio, Jr, MD · Principal investigator
  • Memorial Health University Medical Center
    Savannah, Georgia 31403, United States
    Recruiting
  • Rush University Medical Center
    Chicago, Illinois 60612, United States
    Recruiting
  • Bleeding and Clotting Disorders Institute
    Peoria, Illinois 61664, United States
    Recruiting
    • Sarah Malik · Contactsarawm@ilbcdi.org
    • Jonathan Roberts, MD · Principal investigator
  • Indiana Hemophilia and Thrombosis Center
    Indianapolis, Indiana 46260, United States
    Recruiting
    • Nancy Hoard · Contactnhoard@ihtc.org
    • Amy Shapiro, MD · Principal investigator
  • Iowa Hemophilia and Thrombosis Center
    Iowa City, Iowa 52242, United States
    Recruiting
  • Louisiana Center for Bleeding and Clotting Disorders, Tulane University
    New Orleans, Louisiana 70112, United States
    Recruiting
    • Melody Benton · Contactmbenton@tulane.edu
    • Maissaa Janbain, MD · Principal investigator
  • Maine Hemophilia and Thrombosis Center
    Scarborough, Maine 04074, United States
    Recruiting
  • Johns Hopkins University Hemophilia Treatment Center
    Baltimore, Maryland 21287, United States
    Recruiting
    • Kimberly Jones · Contactkjones62@jhmi.edu
    • Jennifer Keates-Baleeiro, MD · Principal investigator
  • Massachusetts General Hospital Comprehensive Hemophilia and Thrombosis Treatment Center
    Boston, Massachusetts 02114, United States
    Not yet recruiting
  • Central Michigan Children's Hospital of Michigan
    Detroit, Michigan 48201, United States
    Recruiting
    • Negin Salehi · Contactsaleh1n@cmich.edu · (313) 966-8393
    • Madhvi Rajpurkar, MD · Principal investigator
  • Henry Ford Health System Bleeding and Thrombosis Treatment Center
    Detroit, Michigan 48202, United States
    Recruiting
    • Mary Mueller · Contactlmuelle1@hfhs.org · 313-725-7791
    • Philip Kuriakose, MD · Principal investigator
  • Mayo Comprehensive Hemophilia Center
    Rochester, Minnesota 55905, United States
    Recruiting
  • Children's Mercy Hospital - Kansas City
    Kansas City, Missouri 64108, United States
    Recruiting
    • Anna Wiseman · Contactamwiseman@cmh.edu
    • Shannon Carpenter, MD · Principal investigator
  • The John Bouhasin Center for Children with Bleeding Disorders
    St Louis, Missouri 63104, United States
    Recruiting
  • Cure 4 The Kids Foundation
    Las Vegas, Nevada 89135, United States
    Recruiting
  • Hemostasis and Thrombosis Center of Nevada
    Reno, Nevada 89509, United States
    Recruiting
  • Newark Beth Israel Medical Center - Hemophilia Center
    Newark, New Jersey 07122, United States
    Recruiting
  • University of New Mexico Ted R. Montoya Hemophilia & Thrombosis Program
    Albuquerque, New Mexico 87131, United States
    Recruiting
  • Western New York BloodCare
    Buffalo, New York 14202, United States
    Recruiting
  • Northwell Health Hemostasis and Thrombosis Center at Long Island Jewish and Cohen Children's Medical Center
    Hyde Park, New York 11040, United States
    Recruiting
  • Weill Cornell Medical College - New York Presbyterian Hospital
    New York, New York 10065, United States
    Recruiting
  • American Thrombosis and Hemostasis Network
    Rochester, New York 14626, United States
    Recruiting
  • Montefiore Medical Center
    The Bronx, New York 10461, United States
    Recruiting
  • Comprehensive Hemophilia Treatment Center, University of North Carolina at Chapel Hill
    Chapel Hill, North Carolina 27517, United States
    Recruiting
  • St. Jude Affiliate Clinic at Novant Health Hemby Children's Hospital
    Charlotte, North Carolina 28204, United States
    Recruiting
  • East Carolina University Hemophilia Treatment Center
    Greenville, North Carolina 27834, United States
    Recruiting
  • Wake Forest University Health Sciences
    Winston-Salem, North Carolina 27157, United States
    Recruiting
  • Akron Children's Hospital - Showers Center for Cancer & Blood Disorders
    Akron, Ohio 44308, United States
    Recruiting
  • Cincinnati Children's Hospital Medical Center, Hemophilia & Thrombosis Center
    Cincinnati, Ohio 45229, United States
    Recruiting
  • University of Cincinnati Medical Center Hemophilia Treatment Center
    Cincinnati, Ohio 45267, United States
    Recruiting
  • University Hospitals Health System Cleveland
    Cleveland, Ohio 44106, United States
    Recruiting
  • Ohio State University Medical Center
    Columbus, Ohio 43203, United States
    Recruiting
  • Nationwide Children's Hospital Columbus
    Columbus, Ohio 43205, United States
    Recruiting
  • Dayton Children's Hemostasis and Thrombosis Center
    Dayton, Ohio 45404, United States
    Recruiting
  • Northwest Ohio Hemophilia Treatment Center at the Toledo Hospital
    Toledo, Ohio 43606, United States
    Recruiting
  • Children's Hospital of Philadelphia
    Philadelphia, Pennsylvania 19104, United States
    Recruiting
    • Praharsha Konde · Contactkondep@chop.edu
    • Leslie Raffini, MD · Principal investigator
  • Penn Comprehensive Hemophilia and Thrombophilia Program/Hospital of the University of Pennsylvania
    Philadelphia, Pennsylvania 19104, United States
    Recruiting
  • St. Christopher's Hospital for Children
    Philadelphia, Pennsylvania 19134, United States
    Recruiting
  • Hemophilia Center of Western Pennsylvania
    Pittsburgh, Pennsylvania 15213, United States
    Recruiting
    • Deborah Vehec · Contactdvehec@vitalant.org · 412-209-7564
    • Nicoletta Machin, MD · Principal investigator
  • Rhode Island Hospital Hemostasis and Thrombosis Center
    Providence, Rhode Island 02903, United States
    Recruiting
  • St. Jude Children's Research Hospital
    Memphis, Tennessee 38105, United States
    Recruiting
  • Vanderbilt University Medical Center
    Nashville, Tennessee 37212, United States
    Recruiting
  • Children's Blood and Cancer Center of Central Texas
    Austin, Texas 78723, United States
    Recruiting
  • North Texas Hemophilia and Thrombosis Program - Pediatric Program / Center for Cancer & Blood Disorders
    Dallas, Texas 75235, United States
    Recruiting
  • North Texas Comprehensive Hemophilia Treatment Center
    Dallas, Texas 75390, United States
    Recruiting
  • Gulf States Hemophilia and Thrombophilia Center
    Houston, Texas 77030, United States
    Recruiting
  • Texas Children's Hemophilia & Thrombosis Center/Baylor College of Medicine
    Houston, Texas 77030, United States
    Recruiting
  • South Texas Comprehensive Hemophilia and Thrombophilia Treatment Center
    San Antonio, Texas 78229, United States
    Recruiting
    • Shawn Lade · Contactlade@uthscsa.edu
    • Deanna Maida, MD · Principal investigator
  • Children's Hospital of Kings Daughters
    Norfolk, Virginia 23507, United States
    Recruiting
    • Kevin Todd, MD · Contactkevin.toddjr@chkd.org · 757-668-9578
    • Kevin Todd, MD · Principal investigator
  • Washington Center for Bleeding Disorders
    Seattle, Washington 98101, United States
    Recruiting
  • Hemophilia Outreach Center Green Bay
    Green Bay, Wisconsin 54311, United States
    Recruiting
    • Andrea Miller · ContactAndream@hocgb.org · 920-965-0606
    • Kenneth Friedman, MD · Principal investigator
  • Comprehensive Center for Bleeding Disorders
    Milwaukee, Wisconsin 53226, United States
    Recruiting
08

References and documents

Publications

  • Weijer C, Freedman B, Fuks A, Robbins J, Shapiro S, Skrutkowska M. What difference does it make to be treated in a clinical trial? A pilot study. Clin Invest Med. 1996 Jun;19(3):179-83. PubMed 8724821 ↗
  • Braunholtz DA, Edwards SJ, Lilford RJ. Are randomized clinical trials good for us (in the short term)? Evidence for a "trial effect". J Clin Epidemiol. 2001 Mar;54(3):217-24. doi: 10.1016/s0895-4356(00)00305-x. PubMed 11223318 ↗
  • West J, Wright J, Tuffnell D, Jankowicz D, West R. Do clinical trials improve quality of care? A comparison of clinical processes and outcomes in patients in a clinical trial and similar patients outside a trial where both groups are managed according to a strict protocol. Qual Saf Health Care. 2005 Jun;14(3):175-8. doi: 10.1136/qshc.2004.011478. PubMed 15933313 ↗
  • Unger JM, Barlow WE, Martin DP, Ramsey SD, Leblanc M, Etzioni R, Hershman DL. Comparison of survival outcomes among cancer patients treated in and out of clinical trials. J Natl Cancer Inst. 2014 Mar;106(3):dju002. doi: 10.1093/jnci/dju002. Epub 2014 Mar 13. PubMed 24627276 ↗
  • https://www.fda.gov/drugs/resources-information-approved-drugs/hematologyoncology-cancer-approvals-safety-notifications. Accessed 04 Jul 2019
  • https://www.clinicaltrials.gov/ct2/results?cond=Hematologic+Diseases&term=&cntry=&state=&city=&dist=. Accessed 04 Jul 2019
  • Konkle BA, Recht M; members of Working Group 2, the NHLBI State of the Science Workshop on factor VIII inhibitors: Generating a national blueprint for future research. The national blueprint for 21st century data and specimen collection and observational cohort studies: NHLBI State of the Science Workshop on factor VIII inhibitors. Haemophilia. 2019 Jul;25(4):590-594. doi: 10.1111/hae.13772. PubMed 31329362 ↗
  • Iorio A, Keepanasseril A, Foster G, Navarro-Ruan T, McEneny-King A, Edginton AN, Thabane L; WAPPS-Hemo co-investigator network. Development of a Web-Accessible Population Pharmacokinetic Service-Hemophilia (WAPPS-Hemo): Study Protocol. JMIR Res Protoc. 2016 Dec 15;5(4):e239. doi: 10.2196/resprot.6558. PubMed 27977390 ↗

Individual participant data

Plan to share: No

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Started Sep 2020 (actual). Primary completion is estimated for Jun 2035, 177 months after the start.

Of 47 non-industry observational studies under Hematologic Diseases, half reached primary completion within 45 months of starting (the median), counting those still running; a quarter within 13 and three quarters within 190. This study's planned 177 months is above that.

Counting every sponsor, half of 64 studies reached it within 51 months; a quarter within 16 and three quarters within 78.

How these figures are worked out, and which studies are left out of them.

Registered
May 11, 2020
First posted
May 21, 2020
StartActual
Sep 30, 2020
Primary completionEst.
Jun 2035
CompletionEst.
Dec 2035
Last update
Aug 17, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Aug 17, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT04398628
Lead sponsor
American Thrombosis and Hemostasis Network
Collaborators
Pfizer, Hemophilia of Georgia, Inc., Genentech, Inc., CSL Behring, Sanofi, Novo Nordisk A/S, Hemab ApS
Responsible party
Sponsor
First posted
May 21, 2020
Start date
Sep 30, 2020
Primary completion
Jun 2035 (estimated)
Completion
Dec 2035 (estimated)
Last update
Aug 17, 2026

Study contacts

Carol Fedor, ND, RN, CCRC
Contact
cfedor@athn.org
800-360-2846 ext. 122
Nana Ama Afari-Dwamena, MPH
Contact
nafaridwamena@athn.org
800-360-2846 ext. 118
Michael Recht, MD, PhD, MBA
principal investigator · Yale University School of Medicine & National Bleeding Disorders Foundation
Tammuella Chrisentery-Singleton, MD
principal investigator · ATHN, Ochsner Clinic Foundation

Oversight

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

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