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

Not Applicable

Completed

• Conditions: Hemophilia A
• Interventions: Other: FVIII immuno-assay

• Registration Number: NCT00839202
• Lead Sponsor: 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.

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 Timeline

• Study Start: 2006-09
• Primary Completion: 2008-09
• Study Completion: 2009-02
• Study First Submitted: 2009-02-06
• Study First Submitted QC: 2009-02-06
• Study First Posted: 2009-02-09
• Status Verified: 2017-01
• Last Update Submitted: 2017-01-31
• Last Update Posted: 2017-02-01

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 7

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

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
FVIII immuno-assay	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.

Primary Outcome Measures

Name	Time	Method
The level of Factor VIII in pMols	48 hours

Secondary Outcome Measures

Name	Time	Method
The possible role of VWF, factor concentrate type and non-inhibitory antibody presence or absence on the FVIII antigen levels	48 hours

Trial Locations

Locations (1)

Department of Biochemistry University of Vermont; 🇺🇸 Burlington, Vermont, United States