This US study aims to assess hemophilia A patient characteristics and reasons for switching from both patient/caregiver and physician perspectives. For this purpose, this research study will include hemophilia A patients who have switched from an existing therapy to Kovaltry. In doing so, real world evidence will be obtained from both patient and physician perspectives offering key insights for effective therapeutic management of patients with hemophilia A and to more fully understand what drives patient switching from a patient perspective and a physician perspective.



Eligible Ages
Over 2 Years
Eligible Genders
Accepts Healthy Volunteers


Hemophilia A patients who have switched treatment to treatment with KOVALTRY within the
past 50 weeks, who are enrolled the ATHN 2: Factor Switching Study, and who have consented
to participate in the KOVALTRY specific module will be included in this study.

Study Design

Study Type
Observational Model
Time Perspective

Arm Groups

ArmDescriptionAssigned Intervention
Patient/caregiver of Kovaltry (BAY81-8973) Patients who are switching factor replacement products to Kovaltry and patients who have switched factor replacement products to Kovaltry previously
  • Drug: Antihemophilic Factor (Kovaltry, BAY81-8973)
    Kovaltry prescribed by the treating Physician
Physician Group Physicians participating in the study are associated with US hemophilia treatment centers that are affiliated with the ATHN hemophilia treatment center network

Recruiting Locations

Children's National and nearby locations

Children's National Medical Center
Washington, District of Columbia 20010

More Details


Study Contact

Bayer Clinical Trials Contact
(+)1-888-84 22937

Detailed Description

This observational study consists of a patient and a physician survey. This survey will consist of questions developed by Bayer and submitted to the Steering Committee of the existing registry, ATHN-2. Once enrolled to participate in the ATHN-2 registry and provided consent to participate in the Bayer nested study, patients who have switched for another product to Kovaltry within the past 50 weeks or at the time of enrollment will be prompted to answer the additional survey questions.

Conclusion of the ATHN-2 registry is scheduled for 2021. Once data is cleaned and locked by the registry, the data will be delivered to Bayer for conduct of our analyses.


Study information shown on this site is derived from ClinicalTrials.gov (a public registry operated by the National Institutes of Health). The listing of studies provided is not certain to be all studies for which you might be eligible. Furthermore, study eligibility requirements can be difficult to understand and may change over time, so it is wise to speak with your medical care provider and individual research study teams when making decisions related to participation.