Activity and Content of Factor VIII (FVIII) in Human Plasma: The Assessment of a Novel Immunoassay

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00839202
Recruitment Status : Completed
First Posted : February 9, 2009
Last Update Posted : February 1, 2017
University of Vermont
Information provided by (Responsible Party):
Edward Gomperts, Children's Hospital Los Angeles

Brief Summary:
A novel immuno-assay is being evaluated for the measurement of Factor VIII. Current procedure measures a rate assay which is subject to much artefact. The hypothesis is that the new assay will give a reading of absolute quantities of FVIII which will provide a more suitable indicator of FVIII content for clotting factor manufacturers, physicians and patients.

Condition or disease Intervention/treatment Phase
Hemophilia A Other: FVIII immuno-assay Not Applicable

Detailed Description:
Remnant samples collected in a clinical laboratory are assayed with the new procedure and compared with the standard functional activated partial thromboplastin time (APTT) assay. A PK study in seven study subjects with hemophilia A is being carried out using five different commercially licensed factor VIII concentrates and the blood samples drawn for the PK analysis are being measured for FVIII with the novel assay and compared with the standard APTT assay. The concentrates used in the PK studies are also being applied to the two assay systems to determine each product's specific activity.

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 7 participants
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: Pharmacokinetic (PK) Analysis of a Novel Immunoassay in Hemophilia A
Study Start Date : September 2006
Actual Primary Completion Date : September 2008
Actual Study Completion Date : February 2009

Arm Intervention/treatment
Experimental: FVIII immuno-assay
The study is not designed as a therapeutic evaluation, but an assessment of clotting factor VIII timed responses after the infusion of specified doses of licensed clotting factor VIII concentrates. The purpose of the study is to measure the levels of infused licensed clotting factor VIII by standard assay techniques and comparing these standard assays with an experimental assay. Measurements of possible co-factors that might impact the results were also carried out.
Other: FVIII immuno-assay
There is no intervention. This is a study of the differences in assays.

Primary Outcome Measures :
  1. The level of Factor VIII in pMols [ Time Frame: 48 hours ]

Secondary Outcome Measures :
  1. The possible role of VWF, factor concentrate type and non-inhibitory antibody presence or absence on the FVIII antigen levels [ Time Frame: 48 hours ]

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • adults with hemophilia A
  • factor VIII less that 2%
  • informed consent signed
  • absence of an inhibitor

Exclusion Criteria:

  • history of a high responding inhibitor anemia

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00839202

United States, Vermont
Department of Biochemistry University of Vermont
Burlington, Vermont, United States, 05446
Sponsors and Collaborators
Children's Hospital Los Angeles
University of Vermont
Principal Investigator: Edward D Gomperts, MD Children's Hospital Los Angeles
Principal Investigator: Kenneth G Mann, PhD University of Vermont

Responsible Party: Edward Gomperts, Attending Hematologist, Children's Hospital Los Angeles Identifier: NCT00839202     History of Changes
Other Study ID Numbers: CCI-06-0069-CR002
First Posted: February 9, 2009    Key Record Dates
Last Update Posted: February 1, 2017
Last Verified: January 2017
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

Keywords provided by Edward Gomperts, Children's Hospital Los Angeles:
factor VIII
hemophilia A

Additional relevant MeSH terms:
Hemophilia A
Blood Coagulation Disorders, Inherited
Blood Coagulation Disorders
Hematologic Diseases
Coagulation Protein Disorders
Hemorrhagic Disorders
Genetic Diseases, Inborn
Factor VIII