Phase I/II Trial of Lentiviral Gene Transfer for SCID-X1 With Low Dose Targeted Busulfan Conditioning
Trial Parameters
Brief Summary
This is a phase I/II open label multi-center study in which patients will receive low dose targeted busulfan followed by infusion of autologous CD34+ selected bone marrow or mobilized peripheral blood cells transduced with the G2SCID vector. Subjects will be enrolled over 3 years and be followed for 2 years post-infusion on this protocol, then followed long-term on a separate long-term follow-up protocol. Enrollment of subjects will be agreed upon by representatives of both sites. Data will be collected uniformly from both sites through an electronic capture system and key laboratory studies will be centralized. Harvest, cellular manufacturing and infusion will occur at each site using the same SOPs. Key aspects of cellular product characterization will be centralized
Eligibility Criteria
Inclusion Criteria: \- 1. Diagnosis of SCID-X1 based on immunophenotype and lack of T cell function (proliferation to PHA \<10% of the lower limit of normal for the laboratory) AND confirmed by a mutation in IL2RG 2. Lack of an HLA identical (A, B, C, DR, DQ) related donor 3. Age 5 years old or younger 4. Signed informed consent 5. Documentation of willingness to follow up for 15 years post-infusion as currently required by the FDA 6. If the patient has previously undergone allogeneic transplant, lack of donor T cell engraftment must be documented. 7\. Age at least 8 weeks by the time of busulfan administration Exclusion Criteria: 1. Patients with an active, therapy-resistant infection. Infections that are known to be highly morbid in SCID patients will be considered active and therapy-resistant if the infectious agent is repeatedly isolated despite a minimum of 2 weeks of appropriate therapy and is associated with significant organ dysfunction (including but not limited to abnormaliti