Condition category
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Contact information



Primary contact

Dr Lorna Williamson


Contact details

NHS Blood and Transplant (NHSBT)
Department of Haematology
National Blood Service Centre
Long Road
United Kingdom

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Platelet Responsiveness and Outcome from Platelet Transfusion - does inherent variation in donor platelet function affect the clinical efficacy of apheresis platelets? A randomised double blind single centre trial.



Study hypothesis

The PROMPT study is a randomised double blind controlled trial. We want to determine whether the activity/responsiveness of platelets (as defined by in vitro responsiveness to agonists) given to stable patients with thrombocytopenia (low platelet numbers), affects patients’ platelet counts following transfusion. We are also interested in investigating whether there is any change in the patient’s bleeding in the days after the platelet transfusion has been given. We will do this by randomising patients to receive a single platelet transfusion of either high or low responsiveness and monitoring the outcomes. We will also collect some non-randomised ( but still blinded) data on trial units. In addition we will collect the outcome data from some enrolled patients who are given a non-study transfusion of platelets so that we can compare the results to the study transfusions.

Platelets are vitally important cells for blood clotting and, as with many human characteristics (such as height, weight etc), there is a normal range of their functional activity as demonstrated by their responsiveness to agonists. Agonists are biological molecules which “switch on” platelets. This means that the majority of the population have platelets of medium responsiveness; however there is a small percentage of normal individuals who have very active (high responsiveness) or very inactive (low responsiveness) platelets.

It is not fully understood what effect differences in platelet activity levels would have for a patient when they are given a platelet transfusion. It is possible that following transfusion very active platelets are more rapidly removed from the circulation.

More details can be found at:

Ethics approval

Hertfordshire Research Ethics Committee, 20 July 2011 ref: 11/EE/0227

Study design

Randomised interventional trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


National Cancer Research Network, Blood


Patients will be randomised to a single unit from either a low or high responding donor. The responsiveness of the donor's platelets in vitro to agonists ( molecules which "switch on" platelets) has been previously determined and has been shown to be reproducible. In addition up to 30 patients will also be monitored for a non-trial (control) transfusion to determine usual outcome for this patient group.

Duration of follow-up is 5 days or until the next platelet transfusion (whichever is sooner).

Intervention type



Not Applicable

Drug names

Primary outcome measure

Count increment at 1 hour; measured as difference between pre and 1 hour post transfusion count. Corrected for dose and BSA.

Secondary outcome measures

1. 24 hour count increment measured as difference between pre and 24 hour count
2. Bleeding Score - both patient and clinician assessed
3. Red cell transfusion measured as number of red cell units transfused
4. Time to next platelet transfusion measured as number of days to next transfusion

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Age 16 years or older
2. Stable Haematology/Oncology Patients at Addenbrooke’s Hospital
3. Thrombocytopenia secondary to bone marrow failure, requiring platelet transfusions according to local and British Committee for Standards in Haematology (BCSH) Guidelines
4. Patients who, if peripheral venous access for blood sampling is required, have adequate access and will consent to their blood being taken in this way
5. Patients able to give written informed consent
6. Male or female

Participant type


Age group




Target number of participants

UK Sample Size: 130; Description: 100 Trial units and 30 control units.

Participant exclusion criteria

1. Inherited or acquired clotting disorders
2. Inherited or acquired platelet function disorders
3. Current Acute Promyelocytic Leukaemia
4. Previously documented WHO Grade 4 bleeding (debilitating blood loss)
5. Palpable Splenomegaly
6. Immunological refractoriness to platelet transfusion
7. Require HLA or HPA matched platelets
8. Pregnant or lactating women
9. Other active malignancy in past 5 years

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

NHS Blood and Transplant (NHSBT)
United Kingdom

Sponsor information


NHS Blood and Transplant [NHSBT] (UK)

Sponsor details

Research & Development
National R&D Office
500 North Bristol Park
BS34 7QH
United Kingdom

Sponsor type

Hospital/treatment centre



Funder type

Hospital/treatment centre

Funder name

NHS Blood and Transplant [NHSBT] (UK)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

22/06/2016: No publications found, verifying study status with principal investigator