A Study of Previously Untreated Patients (PUPs) with Congenital Hemophilia


About this study

The purpose of this study is to determine the percentage of subjects with confirmed inhibitors (per CDC laboratory criteria; >0.5 Nijmegen Bethesda Units for hemophilia A and >0.3 Nijmegen Bethesda Units for hemophilia B within the first 50 Exposure Days (ED).

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. If you need assistance understanding the eligibility criteria, please contact the study team.

Inclusion Criteria:

  • Congenital hemophilia A; FVIII ≤ 5% or congenital hemophilia B; FIX ≤ 5%.
  • Birth date on or after January 1, 2010.
  • Care established at one of the participating HTCs.
  • Co-enrollment in the ATHNdataset.
  • Parent or authorized guardian can provide informed consent.

Exclusion Criteria:

  • Patients who are referred to the HTC with no record of bleed and factor utilization data.

Participating Mayo Clinic locations

Study statuses change often. Please contact us for help.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Rajiv Pruthi, M.B.B.S.

Open for enrollment

Contact information:

Sandra Heisler L.P.N.



More information


Publications are currently not available

Study Results Summary

Not yet available

Supplemental Study Information

Not yet available


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