Study of Methodologies to Measure Blood Flow and Oxygenation in Adults With Sickle Cell Disease

Study Overview
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Brief Summary
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The purpose of the study is to determine whether imaging techniques, such as magnetic resonance imaging (MRI), near infrared spectroscopy (NIRS), laser speckle contrast imaging (LSCI), and optical imaging (OI), can detect differences in blood flow and oxygen levels in different organ systems of participants with sickle cell disease (SCD). Differences in blood flow and oxygen levels detected by these techniques will be evaluated to determine their utility as biomarkers of clinical disease pathophysiology.

Official Title
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A Study of Methodologies to Measure Blood Flow and Oxygenation as Potential Biomarkers in Adults With Sickle Cell Disease

Conditions
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Healthy, Sickle Cell Disease

Participation Criteria
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Eligibility Criteria
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Key Inclusion Criteria: Have a diagnosis of SCD confirmed by hemoglobin analysis. Be in stable clinical condition, as determined by the Investigator. Subjects enrolled in Part B must also meet the following eligibility criterion at Screening: Receiving scheduled standard of care RBC exchange transfusion therapy, with ≥3 transfusions already received. Be deemed healthy, as determined by the Investigator, based on the physical examination, medical history, vital signs, 12-lead electrocardiogram (ECG), and clinical laboratory measurements. Key Exclusion Criteria: Inability to lie still for ≥5 minutes, claustrophobia sufficient to interfere with generating reliable MRI scans, body weight exceeding 320.0 lbs., or girth exceeding the magnet bore. Presence of a metal device affected by MRI (e.g., any type of electronic, mechanical or magnetic implant, cardiac pacemaker, aneurysm clips, implanted cardiac defibrillator) or potential ferromagnetic foreign body (metal slivers, metal shavings, other metal objects) which would be a contraindication for MRI. Acute pain crisis requiring hospitalization, with a discharge ≤4 weeks prior to the first imaging visit, or when determined by the Investigator to not be at steady state. Recent (≤3 months) treatment with hydroxyurea therapy. NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Part A<br>Cohort 1- Participants with severe SCD (4-10 VOC/year) Cohort 2- Participants with milder SCD (<4-10 VOC/year) Cohort 3- Healthy volunteers Part A and B can occur in parallel | |
| Part B<br>Adults with SCD receiving chronic red blood cell exchange transfusion Part A and B can occur in parallel | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood flow in the brain of adults with severe SCD (4-10 vaso-occlusive crises [VOC]/ year) compared to healthy adults without SCD as assessed by MRI-ASL (arterial spin labeling) |  | Up to day 18 post screening visit | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Kidney blood flow rates as assessed by MRI-SWI (susceptibility-weighted imaging) |  | Up to day 21 post screening visit | 
| Skeletal muscle blood flow rates as assessed by NIRS |  | Up to day 21 post screening visit | 
| Skin blood flow rates as assessed by LSCI |  | Up to day 21 post screening visit | 
| Retinal blood flow rates as assessed by OI |  | Up to day 21 post screening visit | 
| Total oxygen levels in the brain as assessed by MRI-ASL |  | Up to day 21 post screening visit | 
| Total oxygen levels in the kidney as assessed by MRI-SWI |  | Up to day 21 post screening visit | 
| Total oxygen levels in the muscle as assessed by NIRS |  | Up to day 21 post screening visit | 
| Total oxygen levels in the skin as assessed by LSCI |  | Up to day 21 post screening visit | 
| Total oxygen levels in the retina as assessed by OI |  | Up to day 21 post screening visit |