Low Von Willebrand in Ireland Cohort Study (LOVIC)
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|ClinicalTrials.gov Identifier: NCT03167320|
Recruitment Status : Recruiting
First Posted : May 25, 2017
Last Update Posted : February 15, 2019
|Condition or disease|
|Von Willebrand Factor, Deficiency|
All patients with bleeding disorders in Ireland are registered on a national bleeding disorder database and attend the National Centre for Hereditary Coagulation Disorders in St. James's Hospital, Dublin, Ireland for annual review. At review eligible patients will be invited to participate in the Low Von Willebrand in Ireland Cohort (LOVIC) study.
Following consent, an extensive bleeding assessment tool will be administered by a coagulation haematologist to all participants from which the International Society of Thrombosis and Haemostasis Bleeding Assessment Tool (ISTH BAT) and the Condensed Molecular and Clinical Markers for the Diagnosis and Management of Type 1 Von Willebrands Disease (MCMDM-1 VWD) scores can be derived. In addition, blood will be drawn for von Willebrand factor (VWF) measurements, VWF propeptide, platelet VWF. Citrated plasma and DNA will be stored for each patient. The relationship between laboratory parameters, (including von Willebrand factor, platelet VWF, FVIII and concomitant coagulation disorders) and the clinical phenotype in patients with low VWF will be studied. We will assess the effect of the laboratory parameters on the severity of bleeding tendency. In the future mutation analysis of the VWF gene will be performed in all participants in the LOVIC study.
Historical patient records and laboratory results will be reviewed and DDAVP (1-desamino-8-D-arginine vasopressin) fall off studies documented where available. If no previous DDAVP fall off study has been performed patients will be invited to attend.
|Study Type :||Observational|
|Estimated Enrollment :||400 participants|
|Official Title:||Low Von Willebrand in Ireland Cohort Study|
|Study Start Date :||October 2014|
|Estimated Primary Completion Date :||July 2022|
|Estimated Study Completion Date :||July 2022|
Irish patients with low Von Willebrand levels will be have both venous blood sampling and a bleeding score administered at study entry. A DDAVP (1-desamino-8-D-arginine vasopressin) fall off study was organised for those patients in the cohort with no previous fall offs available and no contraindications to DDAVP.
- Number of Irish patients with Low Von Willebrand Factor with abnormal bleeding scores [ Time Frame: at enrolment ]The ISTH-BAT and Condensed MCMDM-1 VWD score of all participants will be determined at enrollment using a physician directed questionnaire using only symptoms prior to their diagnosis with Low VWF. This will help elucidate the bleeding phenotype, if any, associated with Low VWF.
- The number of patients with Low VWF with abnormal plasma VWF clearance [ Time Frame: 2 years ]For each individual enrolled the Von Willebrand factor propeptide (VWF:pp, U/dL), Von Willebrand factor antigen (VWF:Ag IU/dL) and Factor VIII:C (FVIII:C IU/dL) levels at enrolment will be determined. From this data the plasma VWF clearance will be ascertained using the plasma VWF:pp/VWF:Ag ratio. In addition, the FVIII:C/VWF:Ag ratio will be calculated to determine the contribution of altered VWF synthesis to Low VWF.
- The rate of response to DDAVP in Irish patients with low Von Willebrand factor levels [ Time Frame: 3 years ]For each individual with no contraindication a DDAVP trial will be performed with plasma VWF levels taken pre and at 1 and 4 hours post DDAVP. The rate of plasma VWF level fall off for each trial will be determined and the area under the curve (AUC) calculated. Complete response will be defined as a three fold increase from baseline.
- The number of patients with Low VWF with reduced plasma VWF synthesis [ Time Frame: 3 years ]For each individual enrolled the Von Willebrand factor antigen (VWF:Ag IU/dL) and Factor VIII:C (FVIII:C IU/dL) levels at enrolment will be determined. From this data the plasma FVIII:C/VWF:Ag ratio will be calculated to determine the contribution of altered VWF synthesis to Low VWF.
Biospecimen Retention: Samples With DNA
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 ClinicalTrials.gov identifier (NCT number): NCT03167320
|Contact: Michelle Lavin, FRCPathemail@example.com|
|St. James's Hospital||Recruiting|
|Dublin, Ireland, D8|
|Contact: Michelle Lavin, FRCPath +35314162141 firstname.lastname@example.org|
|Sub-Investigator: Niamh M O'Connell, FRCPath,PhD|
|Principal Investigator:||James S O'Donnell, MD,PhD||St. James's Hospital, Dublin Ireland|