VWF platelet study: a pilot study of von Willebrand factor for moderate or severe thrombocytopenia

ISRCTN ISRCTN74679473
DOI https://doi.org/10.1186/ISRCTN74679473
Secondary identifying numbers N/A
Submission date
13/02/2015
Registration date
24/03/2015
Last edited
21/12/2020
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Haematological Disorders
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Record updated in last year

Plain English summary of protocol

Background and study aims
Platelets are blood cells that help the blood clot. They are an important first line of defence against bleeding. Platelet numbers may be low if a person doesn’t make enough platelets or if their platelets are broken down too quickly once they are made. People with low platelet counts are more vulnerable to bleeding. If they undergo surgery or start to bleed, a transfusion of platelets taken from blood donors is often needed to stop the bleeding. Platelet transfusions have a number of disadvantages: supplies are limited, they are expensive, there can be side effects such as bacterial infections and allergic reactions, and some patients do not benefit. Von Willebrand factor (vWF) naturally occurs in the body and causes platelets to stick to sites of injury to stop bleeding. Initial tests have been performed on the blood of volunteers with normal platelet counts. Their blood was treated to lower the platelet count. Adding vWF to the blood samples considerably improved the way their platelets worked. This study aims to investigate in the laboratory if adding vWF to blood from people with low platelet counts could improve the way the platelets work so that platelet transfusions are no longer needed.

Who can participate?
Patients aged 18 or over with low platelet counts (e.g., immune thrombocytopenic purpura or a bone marrow failure syndrome such as myelodysplastic syndrome).

What does the study involve?
Patients with low platelet counts will be asked if they will give extra blood for a laboratory investigation when they next have blood taken. The volume of extra blood is equivalent to three teaspoons and will be rapidly remade by the body. Patients will be asked questions about medications and recent food that they have eaten, as these can cause changes in the test results. The blood samples will be analysed in the laboratory. Firstly the patient’s platelet count will be rechecked. If there are more than 50 billion platelets per litre, it will not be analysed further. If there are less than 50 billion per litre then further tests will be performed to see how well the platelets are working. vWF will then be added to the blood samples and the tests will be repeated.

What are the possible benefits and risks of participating?
There are no direct benefits for patients who agree to take part in the study. We hope that this study will allow us to identify new ways to treat bleeding for patients with low platelet counts in the future. The risk of any complication from extra blood being taken is minimal.

Where is the study run from?
Churchill Hospital (UK).

When is the study starting and how long is it expected to run for?
From April to September 2015.

Who is funding the study?
Investigator initiated and funded (UK).

Who is the main contact?
Dr Michael Desborough

Contact information

Dr Michael Desborough
Public

NHS Blood and Transplant
John Radcliffe Hospital
Oxford
OX3 9DU
United Kingdom

ORCiD logoORCID ID 0000-0002-1951-5616

Study information

Study designObservational single-centre trial
Primary study designObservational
Secondary study design
Study setting(s)Hospital
Study typeOther
Scientific titleVWF platelet study: a pilot observational study of von Willebrand factor for moderate or severe thrombocytopenia
Study acronymvWF Platelet Study
Study objectivesTo determine whether the addition of intermediate purity factor VIII (a source of von Willebrand factor) to the donated blood of thrombocytopenic patients improves their platelet function.
Ethics approval(s)NRES Committee North West - Haydock, 11/02/2015, ref: 15/NW/0138
Health condition(s) or problem(s) studiedImmune thrombocytopenic purpura or thrombocytopenia due to bone marrow failure
InterventionPlatelet function will be tested on blood donated by patients. These tests will be repeated after addition of intermediate purity factor VIII.
Intervention typeOther
Primary outcome measureNormalisation of platelet function, measured with a platelet function analyser 200 adenosine diphosphate/collagen cartridge after addition of intermediate purity factor VIII
Secondary outcome measures1. Normalisation of platelet function, measured with microfluidics using collagen as an agonist under arterial shear force conditions after addition of intermediate purity factor VIII
2. Normalisation of platelet function, measured with a platelet function analyser 200 P2Y2 cartridge after addition of intermediate purity factor VIII
Overall study start date01/04/2015
Completion date31/03/2017

Eligibility

Participant type(s)Patient
Age groupAdult
Lower age limit18 Years
SexBoth
Target number of participants20
Key inclusion criteria1. Age 18 years or over
2. Confirmed diagnosis of immune thrombocytopenic purpura or a bone marrow failure syndrome such as myelodysplastic syndrome
3. Platelet count less than 50x10^9/l
Key exclusion criteria1. Any inherited platelet disorder or von Willebrand disease
2. Use of an antiplatelet agent (e.g. aspirin or clopidogrel) in the 7 days before blood sampling
Date of first enrolment01/04/2015
Date of final enrolment31/03/2017

Locations

Countries of recruitment

  • England
  • United Kingdom

Study participating centre

Churchill Hospital
Old Road
Headington
Oxford
OX3 7LE
United Kingdom

Sponsor information

NHS Blood and Transplant
Hospital/treatment centre

R&D Administration
NHS Blood and Transplant
500 North Bristol Park
Bristol
BS34 7QH
England
United Kingdom

Website http://www.nhsbt.nhs.uk
ROR logo "ROR" https://ror.org/0227qpa16

Funders

Funder type

Other

Investigator initiated and funded (UK)

No information available

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to shareYes
IPD sharing plan summaryAvailable on request
Publication and dissemination planTo be confirmed at a later date
IPD sharing plan

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
HRA research summary 28/06/2023 No No

Editorial Notes

21/12/2020: Internal review.
01/11/2016: Changed recruitment end date from 30/09/2015 to 31/03/2017
28/10/2016: Study end date changed from 01/12/2015 to 31/03/2017