for males ages 18 years and up (full criteria)
at San Francisco, California and other locations
study started
estimated completion



The aim of this prospective, observational study is to establish a dataset on the frequency of bleeding events, as well as other characteristics of bleeding events and FVIII infusions, in patients with clinically severe hemophilia A receiving prophylactic FVIII replacement therapy as standard of care. The data collected from this study may assist in providing baseline information for comparison to the Spark's investigational hemophilia A gene therapy in future Phase 3 studies.

Official Title

A Multi-Center, Observational Study in Males With Hemophilia A


Blood Coagulation Disorder, Blood Coagulation Disorders, Inherited, Coagulation Protein Disorders, Hemophilia A, Genetic Diseases, Inborn, Genetic Diseases, X-Linked, Hematologic Diseases, Hemorrhagic Disorders, Factor VIII Deficiency, Factor VIII, Factor VIII Protein, Recombinant, Hemostatic Disorders, Blood Coagulation Disorders, Inherited Blood Coagulation Disorders, Inborn Genetic Diseases, X-Linked Genetic Diseases, Disease


You can join if…

Open to males ages 18 years and up

  1. Able and willing to provide written informed consent.
  2. Males ≥18 years of age.
  3. Clinically severe hemophilia A
  4. Previous exposure to FVIII therapy
  5. No prior history of hypersensitivity or anaphylaxis associated with an FVIII or intravenous immunoglobulin administration.
  6. No measurable inhibitor against FVIII
  7. Willing to participate and receive treatment in a future Spark hemophilia A gene therapy study.

You CAN'T join if...

  1. Documented active hepatitis B or C within the past 12 months of Screening
  2. Currently on antiviral therapy to treat hepatitis B or C;
  3. Documented significant liver disease within the past 6 months of Screening
  4. Have serological evidence of HIV-1 or HIV-2
  5. Anti-AAV-Spark 200 neutralizing titers ≥1:1
  6. Previously received SPK-8011;
  7. Previously dosed with any investigational or approved gene therapy product at any time or treated with an investigational drug within the last 12 weeks;
  8. Planned surgical procedure in the next 12 months requiring FVIII prophylactic treatment.
  9. Any history of chronic infection or other chronic disease, concurrent clinically significant major disease (such as liver abnormalities or type I diabetes) including active malignancy, except for non-melanoma skin cancer, any other condition or any other unspecified reasons that, in opinion of the Investigator or Sponsor, makes the participant unsuitable for participation and dosing in a future clinical study for Spark's hemophilia A gene therapy.

    10. Unable or unwilling to comply with the schedule of visits and/or study assessments

    described in the protocol.


  • UCSF
    San Francisco California 94117 United States
  • Bloodworks Northwest
    Seattle Washington 98104 United States


in progress, not accepting new patients
Start Date
Completion Date
Spark Therapeutics
Study Type
Expecting 55 study participants
Last Updated