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

Children's Hospital Los Angeles

Status: Completed

Conditions: Hemophilia A

Treatments: Other: FVIII immuno-assay

Study type: Interventional

Funder types: Other

Identifiers

NCT00839202

CCI-06-0069-CR002

Details and patient eligibility

About

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.

Full 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.

Enrollment: 7 patients

Sex: Male

Ages: 18+ years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Basic Science

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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7 participants in 1 patient group

FVIII immuno-assay

Experimental group

Description:

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.

Treatment:

Other: FVIII immuno-assay