Ignite Creation Date:
2024-05-06 @ 8:28 PM
Last Modification Date:
2024-10-26 @ 3:28 PM
Study NCT ID:
NCT06396403
Status:
RECRUITING
Last Update Posted:
2024-05-02
First Post:
2024-04-24
Brief Title:
The Role of Red Cell Characteristics Angiogenesis Viscosity and Oxygenation in the Pathophysiology of Sickle Cell Related Retinopathy
Sponsor:
Academisch Medisch Centrum - Universiteit van Amsterdam AMC-UvA
Organization:
Academisch Medisch Centrum - Universiteit van Amsterdam AMC-UvA
Study Overview
Official Title:
The Role of Red Cell Characteristics Angiogenesis Viscosity and Oxygenation in the Pathophysiology of Sickle Cell Related Retinopathy
Status:
RECRUITING
Status Verified Date:
2024-05
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
RAVOS
Brief Summary:
Objective
to gain insight in the pathogenesis to identify biomarkers to recognize patients at risk for proliferative SCR and to investigate its associations with clinical and laboratory characteristics
Endpoints
The investigators will determine the difference in the above named parameters between patients with and without PSCR
Study design
This case control study will include adult sickle cell disease patients with the HbSS or HbSC genotype For both genotypes 20 patients without sickle cell retinopathy SCR and 20 patients with PSCR will be included resulting in a total of 80 patients Venous blood samples and retinal imaging scans will be collected for each included patient
to gain insight in the pathogenesis to identify biomarkers to recognize patients at risk for proliferative SCR and to investigate its associations with clinical and laboratory characteristics
Endpoints
The investigators will determine the difference in the above named parameters between patients with and without PSCR
Study design
This case control study will include adult sickle cell disease patients with the HbSS or HbSC genotype For both genotypes 20 patients without sickle cell retinopathy SCR and 20 patients with PSCR will be included resulting in a total of 80 patients Venous blood samples and retinal imaging scans will be collected for each included patient
Detailed Description:
Rationale
Sickle cell disease SCD is characterized by chronic hemolysis and recurrent microvascular occlusion resulting in ischemia and organ damage1 This study focuses on retinal damage sickle cell retinopathy SCR SCR results from ischemic vascular disease and secondary angiogenesis but it is unknown which factors play a significant role in the pathogenesis Studies on this subject are still in an early phase34 Our aim is to gain insight in the pathogenesis to identify biomarkers to recognize patients at risk for proliferative SCR and to investigate its associations with clinical and laboratory characteristics The focus of our study is aimed at evaluation of innovative biomarkers of angiogenesis whole blood viscosity and innovative characterization of red blood cell parameters such as deformability adhesiveness and point of sickling as can be measured ex vivo by the Oxygenscan ie red cell sickling capacity The Oxygenscan is a new method to calculate the deformability of red blood cells as a function of the partial pressure of oxygen These novel parameters will be related to clinical characteristics observed in these patients and specific markers of early retinopathy such as vessel density and macula thinning assessed by OCT angiography
Objective
The objective of this study is to gain insight in the pathogenesis to identify the role of red cell characteristics markers of angiogenesis retinal oxygenation and whole blood viscosity in the development of proliferative SCR and to investigate its associations with clinical and laboratory characteristics
Study design
Case control study
Study population
Adult patients with sickle cell disease SCD with a HbSS or HbSC genotype For both genotypes 20 patients without SCR and 20 patients with proliferative SCR will be included The total amount of included patients will be 80 patients
Intervention
venous blood samples 1 EDTA tube and 1 PECT tubes of 4-5 mL each will be collected from all included patients who will be requested to fast 8 hours before the collection of blood If fasting is not desiredpossible a low-fat breakfast can be consumed
Main study parametersendpoints 1 The difference in red blood cell characteristics point of sickling between patients with and without PSCR 2 The difference in plasma levels of parameters representing the level of systemic angiogenesis activity CD105 VEGF CTGF and angiopoietin-2 between patients with and without PSCR 3 The difference in oxygenation of the retina by assessing the vessel density with angio-OCT and by assessing the oxygen saturation in the retinal arterioles and venules with the Oxymap scan in patients with and without PSCR 4 The difference in whole blood viscosity between patients with and without PSCR
Nature and extent of the burden and risks associated with participation benefit and group relatedness
Data from recent ophthalmologic and hematologic examinations will be collected If no recent ophthalmologic examination is available and no further appointments were made yet the patient will be contacted to visit the outpatient clinic for a new appointment Since the appointments are in accordance with the general screening schedule according to the Dutch Guidelines for Sickle Cell Disease these investigations are no extra burden for the patients Venous blood samples will be obtained by venepuncture preferably during the routine venepuncture for scheduled hematological visits so the only extra burden consists of the extra blood aliquots that have be drawn to answer the research questions Venepuncture is a safe and frequently used procedure in the routine care of patients with sickle cell disease Due to the request to fast before the venepuncture appointments will only be scheduled in the morning in order to reduce the burden on the patient as much as possible
Sickle cell disease SCD is characterized by chronic hemolysis and recurrent microvascular occlusion resulting in ischemia and organ damage1 This study focuses on retinal damage sickle cell retinopathy SCR SCR results from ischemic vascular disease and secondary angiogenesis but it is unknown which factors play a significant role in the pathogenesis Studies on this subject are still in an early phase34 Our aim is to gain insight in the pathogenesis to identify biomarkers to recognize patients at risk for proliferative SCR and to investigate its associations with clinical and laboratory characteristics The focus of our study is aimed at evaluation of innovative biomarkers of angiogenesis whole blood viscosity and innovative characterization of red blood cell parameters such as deformability adhesiveness and point of sickling as can be measured ex vivo by the Oxygenscan ie red cell sickling capacity The Oxygenscan is a new method to calculate the deformability of red blood cells as a function of the partial pressure of oxygen These novel parameters will be related to clinical characteristics observed in these patients and specific markers of early retinopathy such as vessel density and macula thinning assessed by OCT angiography
Objective
The objective of this study is to gain insight in the pathogenesis to identify the role of red cell characteristics markers of angiogenesis retinal oxygenation and whole blood viscosity in the development of proliferative SCR and to investigate its associations with clinical and laboratory characteristics
Study design
Case control study
Study population
Adult patients with sickle cell disease SCD with a HbSS or HbSC genotype For both genotypes 20 patients without SCR and 20 patients with proliferative SCR will be included The total amount of included patients will be 80 patients
Intervention
venous blood samples 1 EDTA tube and 1 PECT tubes of 4-5 mL each will be collected from all included patients who will be requested to fast 8 hours before the collection of blood If fasting is not desiredpossible a low-fat breakfast can be consumed
Main study parametersendpoints 1 The difference in red blood cell characteristics point of sickling between patients with and without PSCR 2 The difference in plasma levels of parameters representing the level of systemic angiogenesis activity CD105 VEGF CTGF and angiopoietin-2 between patients with and without PSCR 3 The difference in oxygenation of the retina by assessing the vessel density with angio-OCT and by assessing the oxygen saturation in the retinal arterioles and venules with the Oxymap scan in patients with and without PSCR 4 The difference in whole blood viscosity between patients with and without PSCR
Nature and extent of the burden and risks associated with participation benefit and group relatedness
Data from recent ophthalmologic and hematologic examinations will be collected If no recent ophthalmologic examination is available and no further appointments were made yet the patient will be contacted to visit the outpatient clinic for a new appointment Since the appointments are in accordance with the general screening schedule according to the Dutch Guidelines for Sickle Cell Disease these investigations are no extra burden for the patients Venous blood samples will be obtained by venepuncture preferably during the routine venepuncture for scheduled hematological visits so the only extra burden consists of the extra blood aliquots that have be drawn to answer the research questions Venepuncture is a safe and frequently used procedure in the routine care of patients with sickle cell disease Due to the request to fast before the venepuncture appointments will only be scheduled in the morning in order to reduce the burden on the patient as much as possible
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
False
Is a FDA Regulated Device?:
False
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None