A Study of Prasugrel in Pediatric Participants With Sickle Cell Disease

Exclusion Criteria

• •Known to have hemoglobin C sickle cell (HbSC) or hemoglobin S beta \^plus thalassemia (HbS β\^+ thalassemia) genotypes
• •Vaso-occlusive crisis (VOC) requiring medical attention within 15 days prior to screening
• •Have a concomitant medical illness (for example, terminal malignancy) that in the opinion of the investigator is associated with reduced survival
• •Hepatic dysfunction characterized by alanine aminotransferase (ALT) ≥ 3 times the upper limit of normal (ULN)
• •Renal dysfunction requiring chronic dialysis or creatinine ≥ 1.5 milligrams per deciliter (mg/dL)
• •Contraindication for antiplatelet therapy
• •History of intolerance or allergy to approved thienopyridines (clopidogrel, ticlopidine, or prasugrel)
• •Participants with a hematocrit \<18%
• •History of abnormal or conditional transcranial Doppler \[velocity in middle cerebral or carotid artery ≥170 centimeters per second (cm/sec)\] within the last year
• •Any history of bleeding diathesis
• •Any history of renal papillary necrosis
• •Active internal bleeding
• •History of spontaneous gastrointestinal bleeding
• •Gross hematuria or \> 300 red blood cells (RBC)/high-powered field (HPF) on urinalysis at the time of screening
• •Any history of vitreous hemorrhage
• •Prior history of hemorrhagic or ischemic stroke, a transient ischemic attack (TIA), or other intracranial hemorrhage
• •Have clinical findings, in the judgment of the investigator, associated with an increased risk of bleeding
• •Platelet count \<100,000 per microliter (μl) of blood
• •Have had recent surgery (within 30 days prior to screening) or are scheduled to undergo surgery within the next 60 days
• •History of dysfunctional uteral bleeding, in the judgment of the investigator
• •Treatment with packed RBC or whole blood transfusion therapy within 30 days prior to dosing
• •Any nonsteroidal anti-inflammatory drug (NSAID) use within 5 days prior to screening
• •Any aspirin, warfarin, thienopyridine, or other antiplatelet medication use within 10 days prior to dosing
• •Anticipated use of aspirin, warfarin, thienopyridine, or other antiplatelet medication during the study period