Please assess the completion status of the following clinical trial:

Trial Title: Sparing Conversion to Abnormal TCD (Transcranial Doppler) Elevation (SCATE)

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: PREVENTION
- Time Perspective: None
- Masking: NONE
- Phase: PHASE3
- Number of Arms: 2.0

Eligibility Criteria:
Inclusion Criteria:~1. Pediatric subjects with severe forms of sickle cell anemia (HbSS, HbSβ0 thalassemia, HbSD, HbSOArab)~2. Age: ≥ 2 and \< 11 years of age, at the time of enrollment~3. Conditional TCD Velocity (170 - 199cm/sec) by Transcranial Doppler ultrasonography examination within 3 months of enrollment~4. Parent or guardian willing and able to provide informed consent~5. Ability to comply with study related treatments, evaluations, and follow-up~Exclusion Criteria:~1. Prior abnormal TCD Velocity~2. History of clinical stroke~3. Inability to take or tolerate daily oral hydroxyurea, including~   * Known allergy to hydroxyurea therapy~  * Known positive serology to HIV infection~  * Known malignancy~  * Current lactation~4. Abnormal laboratory values at initial evaluation (temporary exclusions):~   * Hemoglobin concentration \< 6.0 gm/dL~  * Absolute reticulocyte count \< 100 x 10\^9/L with a hemoglobin concentration \< 8.0 gm/dL~  * WBC count \< 3.0 x 10\^9/L~  * Absolute neutrophil count (ANC) \< 1.0 x 10\^9/L~  * Platelet count \< 100 x 10\^9/L~5. Current use of therapeutic agents for sickle cell disease (e.g., hydroxyurea, arginine, decitabine, magnesium, chronic transfusions). Subjects must be off therapeutic agents for sickle cell disease for at least 3 months prior to enrollment.~6. Current participation in other therapeutic clinical trials~7. Serum creatinine more than twice the upper limit for age OR ≥ 1.0 mg/dL~8. Any condition or chronic illness, which in the opinion of the clinical investigator makes participation ill-advised~9. Pregnancy (for post-menarchal females only)~10. Erythrocyte transfusion within the past 2 months~11. Previous stem cell transplant or other myelosuppressive therapy

- Gender: ALL
- Minimum Age: 2 Years
- Maximum Age: 10 Years
- Healthy Volunteers: f

Study Arms:
- Standard Therapy: Observation (Type: NO_INTERVENTION): Half of the subjects will be randomized to clinical observation only, which includes monthly visits with clinical evaluations, laboratory tests, and TCD endpoint examinations
- Hydroxyurea (Type: EXPERIMENTAL): Half of the subjects will be randomized to hydroxyurea, taken as capsules (300 mg, 400 mg, or 500 mg), or as a liquid formulation (100 mg/mL). Hydroxyurea will be administered once daily by mouth. Subjects will be monitored monthly with clinical evaluations, laboratory tests, and TCD endpoint examinations.

Based on this trial design, predict the completion outcome and termination type (if applicable).