A Phase 1/2 Open Label Study Evaluating the Safety and Efficacy of Gene Therapy of the β-Hemoglobinopathies (Sickle Cell Anemia and β-Thalassemia Major) by Transplantation of Autologous CD34+ Stem Cells Transduced Ex Vivo With a Lentiviral β-A-T87Q Globin Vector (LentiGlobin BB305 Drug Product)
Trial Snapshot
- Phase
- Phase 1
- Status
- Completed
- Sponsor
- bluebird bio
- Enrollment
- 7
- Primary Endpoint
- Number of Treated Participants With Successful Neutrophil and Platelet Engraftment
Study Overview
Brief Summary
This is a Phase 1/2, open label, safety, and efficacy study of the administration of LentiGlobin BB305 Drug Product to participants with either transfusion dependent beta-thalassemia (TDT) or sickle cell disease (SCD).
Study Design
- Study Type
- Interventional
- Allocation
- Na
- Intervention Model
- Single Group
- Primary Purpose
- Treatment
- Masking
- None
Eligibility Criteria
- Ages
- 5 Years to 35 Years (Child, Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Be between 5 and 35 years of age, inclusive.
- •Have severe SCD or transfusion dependent beta-thalassemia major, regardless of the genotype with the diagnosis confirmed by Hb studies. Transfusion dependence is defined as requiring at least 100 mL/kg/year of packed red blood cells (pRBCs).
- •Be eligible for allogeneic hematopoietic stem cell transplant (HSCT) based on institutional medical guidelines, but without a matched related donor.
- •Be willing and able, in the Investigator's opinion, to comply with the study procedures outlined in the study protocol.
- •Have been treated and followed for at least the past 2 years in a specialized center that maintained detailed medical records, including transfusion history.
- •Participants with severe SCD also must:
- •Have failed to achieve adequate clinical benefit following hydroxyurea treatment with sufficient dosage, for at least 4 months unless this treatment was not indicated or not well tolerated.
- •Have 1 or more of the following poor prognostic risk factors:
- •Recurrent vaso occlusive crises (at least 2 episodes in the preceding year or in the year prior to start of a regular transfusion program).
- •Presence of any significant cerebral abnormality on magnetic resonance imaging (MRI) (such as stenosis or occlusions).
- •Stroke without any severe cognitive disability.
- •Osteonecrosis of 2 or more joints.
- •Anti-erythrocyte alloimmunization (>2 antibodies).
- •Presence of sickle cell cardiomyopathy documented by Doppler echocardiography.
- •Acute chest syndrome (at least 2 episodes) defined by an acute event with pneumonia-like symptoms (e.g., cough, fever [>38.5°C], acute dyspnea, expectoration, chest pain, findings upon lung auscultation, tachypnea, or wheezing) and the presence of a new pulmonary infiltrate. Participants with a chronic oxygen saturation <90% (excluding periods of SCD crisis) or carbon monoxide diffusing capacity (DLco) less than 60% in the absence of an infection should not be included in the study.
- •Participants with severe SCD and cerebral vasculopathy (defined by overt stroke; abnormal transcranial Doppler [> 170 cm/sec]; or occlusion or stenosis in the polygon of Willis; or presence of Moyamoya disease) may be enrolled only with approval by the Comite de Surveillance after review of safety and efficacy data from >or= 2 SCD participants without cerebral vasculopathy treated with LentiGlobin BB305 Drug Product
Exclusion Criteria
- •Availability of a willing 10 /10 matched human leukocyte antigen (HLA) identical sibling hematopoietic cell donor, unless recommendation for enrollment is provided by the Comite de Surveillance following a review of the case.
- •Clinically significant, active bacterial, viral, fungal, or parasitic infection.
- •Contraindication to anesthesia for bone marrow harvesting.
- •Any prior or current malignancy, myeloproliferative or immunodeficiency disorder.
- •A white blood cell (WBC) count <3×10^9/L and/or platelet count <120×10^9/L.
- •History of major organ damage including:
- •Liver disease, with transaminase levels >3× upper limit of normal.
- •This observation will not be exclusionary if a liver biopsy shows no evidence of extensive bridging fibrosis, cirrhosis, or acute hepatitis.
- •Histopathological evidence of extensive bridging fibrosis, cirrhosis, or acute hepatitis on liver biopsy.
- •Heart disease, with a left ventricular ejection fraction <25%.
- •Kidney disease with a calculated creatinine clearance <30% normal value.
- •Severe iron overload, which in the opinion of the physician is grounds for exclusion.
- •A cardiac T2* <10 ms by magnetic resonance imaging (MRI).
- •Evidence of clinically significant pulmonary hypertension requiring medical intervention.
Arms & Interventions
LentiGlobin BB305 Drug Product
Following myeloablative conditioning with IV busulfan for 4 consecutive days (dose may be adjusted as per protocol) and subsequent daily monitoring of busulfan levels for confirmation of adequate washout, a single dose cluster of differentiation (CD) 34+ cells/kg LentiGlobin BB305 Drug Product was administered to participants by IV infusion.
Intervention: LentiGlobin BB305 Drug Product (Drug)
Outcomes
Primary Outcomes
Number of Treated Participants With Successful Neutrophil and Platelet Engraftment
Time Frame: From time of drug product infusion through Month 24
Neutrophil engraftment was defined as the first of absolute neutrophil count (ANC) \> or = 0.5 × 10\^9/ liter (L) for 3 consecutive days (or 3 consecutive measurements done on separate days), after a post-transplant value less than (\<) 0.5 × 10\^9/L. Platelet engraftment was defined as the first of 3 consecutive platelet values \> or =20 × 10\^9/L for participants with TDT and values \> or =50 × 10\^9/L for participants with SCD obtained on different days with no platelet transfusions administered for 7 days immediately preceding and during the evaluation period. The day of engraftment is the first day of the 3 consecutive platelet measurements.
Time to Successful Neutrophil and Platelet Engraftment
Time Frame: From time of drug product infusion through Month 24
Neutrophil engraftment was defined as the first of ANC \> or = 0.5 × 10\^9/ liter (L) for 3 consecutive days (or 3 consecutive measurements done on separate days), after a post-transplant value \< 0.5 × 10\^9/L). Platelet engraftment was defined as the first of 3 consecutive platelet values \> or =20 × 10\^9/L for participants with TDT and values \> or =50 × 10\^9/L for participants with SCD obtained on different days with no platelet transfusions administered for 7 days immediately preceding and during the evaluation period. The day of engraftment is the first day of the 3 consecutive platelet measurements.
Incidence of Transplant Related Mortality
Time Frame: From screening through 365 days post-transplant
This was the safety outcome measure related to mortality. Transplant related mortality was defined as any death occurring in the study post drug product infusion deemed related to the transplant by the investigator.
Number of Participants With Overall Survival (OS) Events
Time Frame: From time of drug product infusion through Month 24
Overall survival was defined as time from date of LentiGlobin BB305 Drug Product infusion (Day 1) to date of death. Overall survival was censored at the date of last visit if the participant was still alive. Number of participants with OS events were reported.
Percentage of Participants With Vector-Derived Replication-Competent Lentivirus (RCL)
Time Frame: From time of drug product infusion through Month 24
Blood samples were analyzed for detection of RCL using RCL co-culture assay.
Number of Treated Participants With Greater Than (>) 30 Percent (%) Contribution of an Individual Clone As Per Integration Site Analysis (ISA)
Time Frame: From time of drug product infusion through Month 24
Clonal dominance was defined as an ISA result greater than (\>) 90% of the total insertion sites (IS) at any time and a vector copy number (VCN) \> or =0.3, or an initial ISA result of \> 30% of the total IS with a VCN \> or =0.3 followed by a result \> 30% and less than or equal to (\< or =) 90% at first repeat and a result \> 50% at second repeat.
Number of Participants With Adverse Events (AEs) and Serious Adverse Events (SAEs)
Time Frame: From date of Informed Consent signing up to Month 24
An AE was any untoward medical occurrence associated with the use of a drug in participants, whether or not considered drug related. An AE may include a change in physical signs, symptoms, and/or clinically significant laboratory change occurring in any phase of a clinical study. This definition includes inter-current illnesses or injuries, and exacerbation of pre-existing conditions. An SAE was any AE, occurring at any dose and regardless of causality, that resulted in death, was life-threatening, required in-patient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, a congenital anomaly/birth defect, or was considered an important medical event that may jeopardize the participant and may require medical or surgical intervention to prevent an outcome listed previously. The number of participants with AEs and SAEs were evaluated.
Secondary Outcomes
- Percentage of Treated Participants With Transfusion-Dependent β-Thalassemia (TDT) Who Achieved Transfusion Independence (TI)(From time of drug product infusion through Month 24)
- Weighted Average Hemoglobin (Hb) During Period of Transfusion Independence (TI) in Participants With Transfusion-Dependent β-Thalassemia (TDT)(From time of drug product infusion through Month 24)
- Duration of Transfusion Independence (TI) in Participants With Transfusion-Dependent β-Thalassemia (TDT)(From time of drug product infusion through Month 24)
- Time From LentiGlobin BB305 Drug Product Infusion to Last Packed Red Blood Cells (pRBC) Transfusion Prior to Achieving Transfusion Independence (TI) in Participants With Transfusion-Dependent β-Thalassemia (TDT)(From time of drug product infusion through Month 24)
- Time From LentiGlobin BB305 Drug Product Infusion to Achieving Transfusion Independence (TI) in Participants With Transfusion-Dependent β-Thalassemia (TDT)(From time of drug product infusion through Month 24)
- Weighted Average Nadir Hemoglobin (Hb) in Participants With Transfusion-Dependent β-Thalassemia (TDT)(From 6 months post-drug product infusion through Month 24)
- Percentage Change From Baseline in Annualized Packed Red Blood Cell (pRBC) Transfusion Volume(Baseline, From 6 months post-drug product infusion through Month 24)
- Percentage Change From Baseline in Annualized Number of Packed Red Blood Cell (pRBC) Transfusions(Baseline, From 6 months post-drug product infusion through Month 24)
- Number of Participants With Vaso-Occlusive Crisis (VOC) and/or Acute Chest Syndrome (ACS) Events Post Drug Product Infusion in Sickle Cell Disease Participants(From time of drug product infusion through Month 24)
- Therapeutic Globin Expression Measured by Hb Containing β^A -T87Q Globin (HbA^T87Q) in Peripheral Blood(From time of drug product infusion through Month 24)
- Vector Copy Number (VCN) in Peripheral Blood(From time of drug product infusion through Month 24)