The Effect of Voxelotor on Cerebral Hemodynamic Response in Children With Sickle Cell Anemia

Inclusion Criteria: * Written informed parental/guardian consent and participant assent/consent has been obtained per institutional review board (IRB)/Ethics Committee (EC) policy and requirements, consistent with International Conference on Harmonization (ICH) guidelines * Stated willingness to comply with all study procedures and availability for the duration of the study * Male or female participants, ages 4 to 30 years, inclusive * Homozygous hemoglobin SS (HbSS) or hemoglobin S/beta\^0 thalassemia (HbS/β\^0 thal) * Hemoglobin (Hb) ≤10.5 g/dL at baseline * Concomitant hydroxyurea (HU) therapy is allowed if the dose has been stable for at least 3 months with no anticipated need for dose adjustments during the study and no sign of hematological toxicity * Ability to take oral medication and willingness to adhere to daily voxelotor and scheduled DCS/NIRS assessments * If sexually active and female, must agree to abstain from sexual intercourse or to use a highly effective method of contraception throughout the study period and for 30 days after discontinuation of study drug. If sexually active and male, must agree to abstain from sexual intercourse or willing to use barrier methods of contraception throughout the study period and for 30 days after discontinuation of study drug. * Females of child-bearing potential, i.e., who have begun menstruation and are sexually active, are required to have a negative pregnancy test at screening before the initial administration of study…