Please assess the completion status of the following clinical trial:

Trial Title: Lentiviral (LV) Gene Therapy for Adenosine Deaminase (ADA) Deficiency

Study Design Characteristics:
- Allocation: NON_RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: NONE
- Phase: PHASE1/PHASE2
- Number of Arms: 2.0

Eligibility Criteria:
Gene Therapy (On Trial)~Inclusion Criteria:~1. Diagnosis of ADA-SCID confirmed by DNA sequencing or by confirmed absence of \<3% of ADA enzymatic activity in peripheral blood (or for neonates) in umbilical cord blood erythrocytes and/or leukocytes or in cultured fetal cells derived from either chorionic villus biopsy or amniocentesis, prior to institution of Polyethylene glycol-modified ADA (PEG-ADA) replacement therapy~2. Patients who lack a fully Human leukocyte antigen (HLA)-matched family donor~3. Patients (male or female) \<5 years of age OR Patients (male or female) ≥ 5 years to 15 years of age who have preserved thymic function as evidenced by presence of \>10 % naïve T cells (CD4+45RA+27+ cells)~4. Parental/guardian signed informed consent~Exclusion Criteria:~1. Cytogenetic abnormalities on peripheral blood~2. Evidence of active malignant disease~3. Known sensitivity to busulfan~4. If applicable, confirmed pregnancy (to be tested in patients above 12 years old)~Gene Therapy (CUP)~A group of patients were treated under CUP (GOSH special license) either because the study was not yet open and patients needed urgent treatment, or because they were outside of the inclusion/exclusion criteria or received Investigational Medicinal Product (IMP) followed a different process (ie, received in two infusions). Patients followed the same protocol steps and study visits.~Historical Control Group~Inclusion Criteria:~1. Diagnosis of ADA-SCID confirmed by DNA sequencing OR by confirmed absence of \<3% of ADA enzymatic activity in peripheral blood or (for neonates) in umbilical cord blood erythrocytes and/or leucocytes or in cultured foetal cells derived from either chorionic villus biopsy or amniocentesis, prior to institution of PEG-ADA replacement therapy~2. Patients (male or female) between 0-18 years at time of treatment~3. Patient treated with allogeneic haematopoietic stem cell transplantation since 2000

- Gender: ALL
- Minimum Age: None
- Maximum Age: 15 Years
- Healthy Volunteers: f

Study Arms:
- Gene Therapy (Type: EXPERIMENTAL): Infusion of autologous EFS-ADA LV CD34+ cells
- Historical Control Group (Type: OTHER): Historical data from ADA-SCID patients who were treated with Hematopoietic Stem Cell Transplantation (HSCT)

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