Gene Therapy for Transfusion Dependent Beta-thalassemia

Study Overview
=================
Brief Summary
-----------------
This is a phase I/II study evaluating safety and efficacy of autologous hematopoietic stem cells genetically modified with GLOBE lentiviral vector encoding for the human beta-globin gene for the treatment of patients affected by transfusion dependent beta-thalassemia

Detailed Description
-----------------
Both adults and pediatric patients will be treated with genetically modified autologous hematopoietic stem cells collected from mobilized peripheral blood (or bone marrow for patients < 8 years in case mobilization will not be feasible) and transduced with GLOBE lentiviral vector encoding for the human beta-globin gene. This study will enroll 10 patients allocated in 3 groups, according to age and conditioning regimen: 3 adults (≥18 years) conditioned with treosulfan and thiotepa 3 elderly children (8-17 years) conditioned with treosulfan and thiotepa 4 younger children (3-7 years) conditioned with treosulfan and thiotepa Enrolment will start in adult patients. Pediatric patients will be included once evidence of preliminary safety and biological efficacy is shown in at least 2 adults. Patients are included regardless of the beta globin gene mutation, provided an adequate cardiac, renal, hepatic and pulmonary function is demonstrated. Patients with severe iron overload are excluded as well as patients with active viral infections. Pediatric patients can be enrolled only in absence of a human leukocyte antigen (HLA)-identical sibling or a suitable 10/10 matched unrelated donor. The treated patients will be followed for 2 years. After completion of the 2 years follow up, patients will be enrolled in a long term follow up study and followed up for at least other additional 6 years.

Official Title
-----------------
A Phase I/II Study Evaluating Safety and Efficacy of Autologous Hematopoietic Stem Cells Genetically Modified With GLOBE Lentiviral Vector Encoding for the Human Beta-globin Gene for the Treatment of Patients Affected by Transfusion Dependent Beta-thalassemia

Conditions
-----------------
Beta-Thalassemia

Intervention / Treatment
-----------------
* Genetic: Autologous hematopoietic stem cells genetically modified with GLOBE lentiviral vector encoding for the human beta-globin gene


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Written informed consent Transfusion-dependent beta-thalassemia (any genotype). Transfusion dependence is defined as receiving ≥ 8 transfusions of blood per year over a minimum of 2 years. Karnofsky Index or Lansky > 80% Age ≥ 3 years and < 65 years Adequate cardiac, renal, hepatic and pulmonary functions as evidenced by: Left ventricular ejection fraction (LVEF) greater than 45% by echo and normal ECG or presence of abnormalities not significant for cardiac disease. Absence of severe pulmonary hypertension Diffusing capacity of the lung for carbon monoxide (DLCO) > 50% and forced expiratory volume in 1 sec (FEV1) and forced expiratory vital capacity (FVC) > 60% predicted (if non cooperative: pulse oximetry > 95 % in room air) Serum creatinine < 1.5 upper limit of normal Absent-mild-moderate liver iron overload on T2*MRI (less than 12 months before enrolment) Absent-mild-moderate cardiac iron overload T2*MRI (less than 12 months before enrolment) Absence of severe liver fibrosis or cirrhosis on fibroscan or liver biopsy (less than 12 months before enrolment) Low risk thrombophilic screen and negative history of significant previous thrombotic events For all patients in reproductive age, agreement to use highly effective and adequate method of contraception while receiving treatment phase and for at least 12 months following drugs administration (including both females of child bearing potential and males with partners of child bearing potential) Good adherence to transfusion and chelation programme as indirect evidence of good adherence to treatment and follow-up evaluations for current trial Availability of an adequate and well documented transfusion history (at least previous 6 months) or availability to follow a regular transfusion regimen according to guidelines and provide a detailed transfusion record of the 6 months prior to intervention phase Exclusion Criteria: Use of other investigational agents within 4 weeks prior to study enrolment (within 6 weeks if use of long-acting agents) Severe, active viral, bacterial, or fungal infection at eligibility evaluation Malignant neoplasia (except local skin cancer or cervical intraepithelial neoplasia) or exceptional family history of familial cancer syndromes Myelodysplasia, cytogenetic alterations associated with neoplasia, or other serious haematological disorder than thalassemia History of uncontrolled seizures Other clinical conditions judged non compatible with the procedure and/or the treatment Positivity for HIV (serology or RNA), and/or HbsAg and/or HBV DNA and/or HCV RNA (or negative HCV RNA but on antiviral treatment) and/or Treponema Pallidum or Mycoplasma active infection Active alcohol or substance abuse within 6 months of the study Pregnancy or lactation Previous allogeneic bone marrow transplantation or gene therapy For paediatric patients only: availability of an HLA-matched donor (sibling or of a suitable 10/10 matched unrelated donor).

Ages Eligible for Study
-----------------
Minimum Age: 3 Years
Maximum Age: 64 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Adults<br>≥18 years (3 subjects) The ATIMP consists of autologous CD34+ cell enriched fraction containing hematopoietic stem cells (HSC) transduced with the GLOBE lentiviral vector encoding for the beta-globin gene re-suspended in their final formulation medium. Dosage indications The target dose in the transduced product is 5x10(6) cells/Kg CD34+cells, with a minimum dose of 2x10(6)/Kg and a maximum dose of 20x10(6)/Kg, depending on the yield of cells. The product will be injected intraosseously. | Genetic: Autologous hematopoietic stem cells genetically modified with GLOBE lentiviral vector encoding for the human beta-globin gene<br>* Autologous CD34+ cell enriched fraction containing hematopoietic stem cells (HSC) transduced with the GLOBE lentiviral vector encoding for the human beta-globin gene resuspended in their final formulation medium. The target dose in the transduced product is 5x10^6 cells/Kg CD34+ cells, with a minimum dose of 2 x 10^6/Kg and a maximum dose of 20 x 10^6/Kg, depending on the yield of cells. The product will be injected intraosseously.<br>|
| Experimental: Elderly children<br>8-17 years (3 subjects) The ATIMP consists of autologous CD34+ cell enriched fraction containing hematopoietic stem cells (HSC) transduced with the GLOBE lentiviral vector encoding for the beta-globin gene re-suspended in their final formulation medium. Dosage indications The target dose in the transduced product is 5x10(6) cells/Kg CD34+cells, with a minimum dose of 2x10(6)/Kg and a maximum dose of 20x10(6)/Kg, depending on the yield of cells. The product will be injected intraosseously. | Genetic: Autologous hematopoietic stem cells genetically modified with GLOBE lentiviral vector encoding for the human beta-globin gene<br>* Autologous CD34+ cell enriched fraction containing hematopoietic stem cells (HSC) transduced with the GLOBE lentiviral vector encoding for the human beta-globin gene resuspended in their final formulation medium. The target dose in the transduced product is 5x10^6 cells/Kg CD34+ cells, with a minimum dose of 2 x 10^6/Kg and a maximum dose of 20 x 10^6/Kg, depending on the yield of cells. The product will be injected intraosseously.<br>|
| Experimental: Younger children<br>3-7 years (4 subjects) The ATIMP consists of autologous CD34+ cell enriched fraction containing hematopoietic stem cells (HSC) transduced with the GLOBE lentiviral vector encoding for the beta-globin gene re-suspended in their final formulation medium. Dosage indications The target dose in the transduced product is 5x10(6) cells/Kg CD34+cells, with a minimum dose of 2x10(6)/Kg and a maximum dose of 20x10(6)/Kg, depending on the yield of cells. The product will be injected intraosseously. | Genetic: Autologous hematopoietic stem cells genetically modified with GLOBE lentiviral vector encoding for the human beta-globin gene<br>* Autologous CD34+ cell enriched fraction containing hematopoietic stem cells (HSC) transduced with the GLOBE lentiviral vector encoding for the human beta-globin gene resuspended in their final formulation medium. The target dose in the transduced product is 5x10^6 cells/Kg CD34+ cells, with a minimum dose of 2 x 10^6/Kg and a maximum dose of 20 x 10^6/Kg, depending on the yield of cells. The product will be injected intraosseously.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall survival | Number of patients alive all over the trial | 2 years | 
| Achievement of hematological engraftment | Haematological engraftment is defined as first day of neutrophil count >500/mm3 and platelets >20,000/mm3 on 3 consecutive blood counts. | within day +60 after gene therapy | 
| Safety of the administration of autologous haematopoietic stem cells transduced with LV-GLOBE | short-term tolerability: the percentage of patients not experiencing short-term (0-24 hours from injection) adverse events (of any grade) and systemic reactions. absence of Replication Competent Lentivirus (RCL): the percentage of subjects without RCL in the 24 months from injection. absence of abnormal clonal proliferation: the percentage of subjects without abnormal clonal proliferation in the 24 months from injection. | 0-24 months after gene therapy | 
| Short-term safety and tolerability of the different conditioning regimens | The percentage of patients with the following clinical events from day -5 to +100 days from injection: NCI (National Cancer Institute Common Terminology Criteria grading) ≥2 and metabolic/laboratory NCI ≥3. | from day -5 (first day of conditioning treatment) to day 100 after gene therapy | 
| Overall safety and tolerability measured by AE recording | The number of AEs (adverse events) and SAEs (serious adverse events) and the percentage of subjects experiencing AEs and SAEs in the 24 months post injection will be summarized by severity and within body system involved. | 0-24 months after gene therapy | 
| Polyclonal engraftment | The percentage of subjects with polyclonality of haematopoiesis will be estimated at 6, 12, 18 and 24 months from injection. Polyclonality of haematopoiesis will be defined as > 1000 unique integration sites retrieved from peripheral blood and/or bone marrow cells. | From 6 months to 2 years after gene therapy | 
| Reduction in transfusion frequency up to transfusion independence | Transfusions will be recorded as mLs of blood/kg/months | from -7 months before gene therapy to 2 years after gene therapy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Transfusion independence | Transfusion independence is defined as ≤ 1 transfusion in the previous 6 months | 9 months, 1, 1.5 and 2 years after gene therapy | 
| Adequate haemoglobin level | Haemoglobin level will be assessed by full blood counts in patients achieving transfusion independence. Adequate haemoglobin is defined as haemoglobin >9 g/dl in adults and >10 g/dl in children. | 0-24 months after gene therapy | 
| Adequate engraftment of genetically corrected cells | Engraftment will be assessed by vector-specific quantitative Polymerase Chain reaction (PCR) on bone marrow. Adequate engraftment is defined as ≥ 0.15 VCN/genome. (VCN = Vector Copy Number) | 6, 12, and 24 months after gene therapy | 
| Transgene expression | Transgene expression will be evaluated by globin chains and/or hemoglobin synthesis on peripheral blood and/or bone marrow samples by HPLC and/or electrophoresis analysis | 6, 12, and 24 months after gene therapy | 
| Improvement of health-related quality of life | Health-related quality of life will be assessed by the use of standardized questionnaires | 12 and 24 months | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Beta thalassemia, Gene therapy, Lentiviral vector