Skip to content

A Study Evaluating the Safety and Efficacy of LentiGlobin BB305 Drug Product in β-Thalassemia Major (Also Referred to as Transfusion-dependent β-Thalassemia [TDT]) and Sickle Cell Disease

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)

Status
Completed
Phases
Phase 1Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02151526
Enrollment
7
Registered
2014-05-30
Start date
2013-06-07
Completion date
2019-02-26
Last updated
2022-04-26

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Beta-Thalassemia Major, Sickle Cell Disease

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).

Interventions

LentiGlobin BB305 Drug Product was administered by intravenous (IV) infusion.

Sponsors

Genetix Biotherapeutics Inc.
Lead SponsorINDUSTRY

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
5 Years to 35 Years
Healthy volunteers
No

Inclusion criteria

1. Be between 5 and 35 years of age, inclusive. 2. 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). 3. Be eligible for allogeneic hematopoietic stem cell transplant (HSCT) based on institutional medical guidelines, but without a matched related donor. 4. Be willing and able, in the Investigator's opinion, to comply with the study procedures outlined in the study protocol. 5. 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: 6. 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. 7. 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. 8. 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

1. 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. 2. Clinically significant, active bacterial, viral, fungal, or parasitic infection. 3. Contraindication to anesthesia for bone marrow harvesting. 4. Any prior or current malignancy, myeloproliferative or immunodeficiency disorder. 5. A white blood cell (WBC) count \<3×10\^9/L and/or platelet count \<120×10\^9/L. 6. 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.

Design outcomes

Primary

MeasureTime frameDescription
Number of Treated Participants With Successful Neutrophil and Platelet EngraftmentFrom time of drug product infusion through Month 24Neutrophil 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 EngraftmentFrom time of drug product infusion through Month 24Neutrophil 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 MortalityFrom screening through 365 days post-transplantThis 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) EventsFrom time of drug product infusion through Month 24Overall 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)From time of drug product infusion through Month 24Blood 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)From time of drug product infusion through Month 24Clonal 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)From date of Informed Consent signing up to Month 24An 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

MeasureTime frameDescription
Percentage Change From Baseline in Annualized Number of Packed Red Blood Cell (pRBC) TransfusionsBaseline, From 6 months post-drug product infusion through Month 24Percentage change from baseline in annualized number of pRBC transfusions from 6 months post-drug product infusion through last visit were reported.
Number of Participants With Vaso-Occlusive Crisis (VOC) and/or Acute Chest Syndrome (ACS) Events Post Drug Product Infusion in Sickle Cell Disease ParticipantsFrom time of drug product infusion through Month 24Number of VOCs, ACS, and vaso-occlusive events (VOEs; which included both VOC and ACS) through 24 months after drug product infusion.
Percentage of Treated Participants With Transfusion-Dependent β-Thalassemia (TDT) Who Achieved Transfusion Independence (TI)From time of drug product infusion through Month 24TI was defined as a weighted average hemoglobin (Hb) \> or =9 grams per deciliter (g/dL) without any pRBC transfusions for a continuous period of \> or =12 months at any time during the study after drug product infusion, where calculation of time period of TI starts when participants achieve a Hb \> or =9 g/dL with no transfusions in the preceding 60 days.
Vector Copy Number (VCN) in Peripheral BloodFrom time of drug product infusion through Month 24LentiGlobin BB305 lentiviral vector (LVV) transduction efficiency was measured by VCN. The presence of vector sequences in the genomic DNA of cells is detected using quantitative polymerase chain reaction (qPCR), and results were expressed as VCN.
Therapeutic Globin Expression Measured by Hb Containing β^A -T87Q Globin (HbA^T87Q) in Peripheral BloodFrom time of drug product infusion through Month 24Therapeutic globin expression was measured by HbA\^T87Q in peripheral blood and the ratio of alpha(α)- globin to all beta (β)-like-globins. The relative amount of each globin produced by a participant (including βA\^A-T87Q globin) was determined in peripheral blood throughout the study.
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 24TI was defined as a weighted average hemoglobin (Hb) \> or =9 grams per deciliter (g/dL) without any pRBC transfusions for a continuous period of \> or =12 months at any time during the study after drug product infusion, where calculation of time period of TI starts when participants achieve a Hb \> or =9 g/dL with no transfusions in the preceding 60 days.
Duration of Transfusion Independence (TI) in Participants With Transfusion-Dependent β-Thalassemia (TDT)From time of drug product infusion through Month 24TI was defined as a weighted average Hb \> or =9 grams per deciliter (g/dL) without any pRBC transfusions for a continuous period of \> or =12 months at any time during the study after drug product infusion, where calculation of time period of TI starts when participants achieve a Hb \> or =9 g/dL with no transfusions in the preceding 60 days. To meet the initial TI criteria, the weighted Hb must be \> or =9 g/dL at the end of the 12-month period, to remain in the TI state beyond the 12-month period, the treated participant needs to maintain a weighted Hb of \> or =9 g/dL from that point forward, without receiving a pRBC transfusion. This outcome measure reports the duration of TI and was evaluated in the TDT Transplant Population (TP) that reached TI.
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 24TI was defined as a weighted average Hb \> or =9 grams per deciliter (g/dL) without any pRBC transfusions for a continuous period of \> or =12 months at any time during the study after drug product infusion, where calculation of time period of TI starts when participants achieve a Hb \> or =9 g/dL with no transfusions in the preceding 60 days. To meet the initial TI criteria, the weighted Hb must be \> or =9 g/dL at the end of the 12-month period, to remain in the TI state beyond the 12-month period, the treated participant needs to maintain a weighted Hb of \> or =9 g/dL from that point forward, without receiving a pRBC transfusion. This endpoint reports the time from infusion to the last pRBC transfusion prior to achieving TI.
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 24TI was defined as a weighted average Hb \> or =9 grams per deciliter (g/dL) without any pRBC transfusions for a continuous period of \> or =12 months at any time during the study after drug product infusion, where calculation of time period of TI starts when participants achieve a Hb \> or =9 g/dL with no transfusions in the preceding 60 days. To meet the initial TI criteria, the weighted Hb must be \> or =9 g/dL at the end of the 12-month period, to remain in the TI state beyond the 12-month period, the treated participant needs to maintain a weighted Hb of \> or =9 g/dL from that point forward, without receiving a pRBC transfusion. This outcome measure reports the time from infusion to achievement of TI.
Weighted Average Nadir Hemoglobin (Hb) in Participants With Transfusion-Dependent β-Thalassemia (TDT)From 6 months post-drug product infusion through Month 24Weighted average Hb nadir was defined as an average area under the curve where the Hb closest but within 3 days prior to a transfusion was used as the Hb nadir. Hb values on the day of the transfusion were considered for nadir calculations.
Percentage Change From Baseline in Annualized Packed Red Blood Cell (pRBC) Transfusion VolumeBaseline, From 6 months post-drug product infusion through Month 24Percent change from baseline in the average annual transfusion volume from 6 months post-drug product infusion through last visit were reported.

Countries

France

Participant flow

Recruitment details

This study was conducted at a single site in France between 07 June 2013 (First participant signed informed consent) and 26 February 2019 (Last participant last visit).

Pre-assignment details

A total of 7 participants were treated in a single arm and completed the study. Data was planned, analyzed and reported separately for 3 participants with Sickle Cell Disease (SCD) and 4 participants with transfusion-dependent β-thalassemia (TDT).

Participants by arm

ArmCount
LentiGlobin BB305 Drug Product for SCD
Following myeloablative conditioning with a dose (dose may be adjusted as per protocol) of 3.2 milligram per kilogram per day (mg/kg/day) busulfan intravenous (IV) for 4 consecutive days and subsequent daily monitoring of busulfan levels for confirmation of adequate washout, a single dose of greater than or equal to (\> or =) 2.0×10\^6 cluster of differentiation (CD) 34+ cells/kg LentiGlobin BB305 Drug Product was administered to participants with SCD by IV infusion.
3
LentiGlobin BB305 Drug Product for TDT
Following myeloablative conditioning with a dose (dose may be adjusted as per protocol) of 3.2 mg/kg/day busulfan Intravenous (IV) for 4 consecutive days and subsequent daily monitoring of busulfan levels for confirmation of adequate washout, a single dose of \> or =3.0 × 10\^6 CD34+ cells/kg LentiGlobin BB305 Drug Product (betibeglogene autotemcel) was administered to participants with TDT by IV infusion.
4
Total7

Baseline characteristics

CharacteristicLentiGlobin BB305 Drug Product for SCDLentiGlobin BB305 Drug Product for TDTTotal
Age, Categorical
<=18 years
2 Participants3 Participants5 Participants
Age, Categorical
>=65 years
0 Participants0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
1 Participants1 Participants2 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants0 Participants0 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
3 Participants4 Participants7 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants2 Participants2 Participants
Race (NIH/OMB)
Black or African American
2 Participants0 Participants2 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
1 Participants2 Participants3 Participants
Sex: Female, Male
Female
2 Participants2 Participants4 Participants
Sex: Female, Male
Male
1 Participants2 Participants3 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 30 / 4
other
Total, other adverse events
3 / 34 / 4
serious
Total, serious adverse events
3 / 33 / 4

Outcome results

Primary

Incidence of Transplant Related Mortality

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.

Time frame: From screening through 365 days post-transplant

Population: This outcome measure was evaluated in the Transplant Population (TP).

ArmMeasureValue (NUMBER)
LentiGlobin BB305 Drug Product for SCDIncidence of Transplant Related Mortality0 Number of deaths reported
LentiGlobin BB305 Drug Product for TDTIncidence of Transplant Related Mortality0 Number of deaths reported
Primary

Number of Participants With Adverse Events (AEs) and Serious Adverse Events (SAEs)

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.

Time frame: From date of Informed Consent signing up to Month 24

Population: This outcome measure was evaluated in the ITT population.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
LentiGlobin BB305 Drug Product for SCDNumber of Participants With Adverse Events (AEs) and Serious Adverse Events (SAEs)Number of Participants with any Adverse Event3 Participants
LentiGlobin BB305 Drug Product for SCDNumber of Participants With Adverse Events (AEs) and Serious Adverse Events (SAEs)Number of participants with any SAE3 Participants
LentiGlobin BB305 Drug Product for TDTNumber of Participants With Adverse Events (AEs) and Serious Adverse Events (SAEs)Number of Participants with any Adverse Event4 Participants
LentiGlobin BB305 Drug Product for TDTNumber of Participants With Adverse Events (AEs) and Serious Adverse Events (SAEs)Number of participants with any SAE3 Participants
Primary

Number of Participants With Overall Survival (OS) Events

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.

Time frame: From time of drug product infusion through Month 24

Population: Intent to Treat (ITT) population consisted of all participants who initiated any study procedures, beginning with mobilization (by Granulocyte colony stimulating factor \[G-CSF\] with or without plerixafor), or bone marrow harvest.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
LentiGlobin BB305 Drug Product for SCDNumber of Participants With Overall Survival (OS) EventsCensored Participants3 Participants
LentiGlobin BB305 Drug Product for SCDNumber of Participants With Overall Survival (OS) EventsParticipants reported OS events0 Participants
LentiGlobin BB305 Drug Product for TDTNumber of Participants With Overall Survival (OS) EventsCensored Participants4 Participants
LentiGlobin BB305 Drug Product for TDTNumber of Participants With Overall Survival (OS) EventsParticipants reported OS events0 Participants
Primary

Number of Treated Participants With Greater Than (>) 30 Percent (%) Contribution of an Individual Clone As Per Integration Site Analysis (ISA)

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.

Time frame: From time of drug product infusion through Month 24

Population: This outcome measure was evaluated in the Transplant Population (TP).

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
LentiGlobin BB305 Drug Product for SCDNumber of Treated Participants With Greater Than (>) 30 Percent (%) Contribution of an Individual Clone As Per Integration Site Analysis (ISA)0 Participants
LentiGlobin BB305 Drug Product for TDTNumber of Treated Participants With Greater Than (>) 30 Percent (%) Contribution of an Individual Clone As Per Integration Site Analysis (ISA)0 Participants
Primary

Number of Treated Participants With Successful Neutrophil and Platelet Engraftment

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 frame: From time of drug product infusion through Month 24

Population: Transplant Population (TP) included all participants in the Intent to treat population who underwent LentiGlobin BB305 Drug Product infusion.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
LentiGlobin BB305 Drug Product for SCDNumber of Treated Participants With Successful Neutrophil and Platelet EngraftmentParticipants with Neutrophil Engraftment3 Participants
LentiGlobin BB305 Drug Product for SCDNumber of Treated Participants With Successful Neutrophil and Platelet EngraftmentParticipants with Platelet Engraftment3 Participants
LentiGlobin BB305 Drug Product for TDTNumber of Treated Participants With Successful Neutrophil and Platelet EngraftmentParticipants with Neutrophil Engraftment4 Participants
LentiGlobin BB305 Drug Product for TDTNumber of Treated Participants With Successful Neutrophil and Platelet EngraftmentParticipants with Platelet Engraftment4 Participants
Primary

Percentage of Participants With Vector-Derived Replication-Competent Lentivirus (RCL)

Blood samples were analyzed for detection of RCL using RCL co-culture assay.

Time frame: From time of drug product infusion through Month 24

Population: This outcome measure was evaluated in the ITT population.

ArmMeasureValue (NUMBER)
LentiGlobin BB305 Drug Product for SCDPercentage of Participants With Vector-Derived Replication-Competent Lentivirus (RCL)0 Percentage of participants
LentiGlobin BB305 Drug Product for TDTPercentage of Participants With Vector-Derived Replication-Competent Lentivirus (RCL)0 Percentage of participants
Primary

Time to Successful Neutrophil and Platelet Engraftment

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.

Time frame: From time of drug product infusion through Month 24

Population: This outcome measure was evaluated in the Transplant Population (TP).

ArmMeasureGroupValue (MEDIAN)
LentiGlobin BB305 Drug Product for SCDTime to Successful Neutrophil and Platelet EngraftmentTime to Neutrophil Engraftment32 Days
LentiGlobin BB305 Drug Product for SCDTime to Successful Neutrophil and Platelet EngraftmentTime to Platelet Engraftment51 Days
LentiGlobin BB305 Drug Product for TDTTime to Successful Neutrophil and Platelet EngraftmentTime to Neutrophil Engraftment16.5 Days
LentiGlobin BB305 Drug Product for TDTTime to Successful Neutrophil and Platelet EngraftmentTime to Platelet Engraftment23 Days
Secondary

Duration of Transfusion Independence (TI) in Participants With Transfusion-Dependent β-Thalassemia (TDT)

TI was defined as a weighted average Hb \> or =9 grams per deciliter (g/dL) without any pRBC transfusions for a continuous period of \> or =12 months at any time during the study after drug product infusion, where calculation of time period of TI starts when participants achieve a Hb \> or =9 g/dL with no transfusions in the preceding 60 days. To meet the initial TI criteria, the weighted Hb must be \> or =9 g/dL at the end of the 12-month period, to remain in the TI state beyond the 12-month period, the treated participant needs to maintain a weighted Hb of \> or =9 g/dL from that point forward, without receiving a pRBC transfusion. This outcome measure reports the duration of TI and was evaluated in the TDT Transplant Population (TP) that reached TI.

Time frame: From time of drug product infusion through Month 24

Population: This outcome measure was evaluated only in Transplant Population (TP) with TDT. The number of participants analyzed signifies participants who were evaluable for this specific outcome measure.

ArmMeasureValue (MEDIAN)
LentiGlobin BB305 Drug Product for SCDDuration of Transfusion Independence (TI) in Participants With Transfusion-Dependent β-Thalassemia (TDT)21.7 Month
Secondary

Number of Participants With Vaso-Occlusive Crisis (VOC) and/or Acute Chest Syndrome (ACS) Events Post Drug Product Infusion in Sickle Cell Disease Participants

Number of VOCs, ACS, and vaso-occlusive events (VOEs; which included both VOC and ACS) through 24 months after drug product infusion.

Time frame: From time of drug product infusion through Month 24

Population: This outcome measure was evaluated in ITT population. This outcome measure was only planned to evaluate in SCD participants. Events of VOC and ACS were from same participant.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
LentiGlobin BB305 Drug Product for SCDNumber of Participants With Vaso-Occlusive Crisis (VOC) and/or Acute Chest Syndrome (ACS) Events Post Drug Product Infusion in Sickle Cell Disease ParticipantsVaso-Occlusive Crisis (VOC)1 Participants
LentiGlobin BB305 Drug Product for SCDNumber of Participants With Vaso-Occlusive Crisis (VOC) and/or Acute Chest Syndrome (ACS) Events Post Drug Product Infusion in Sickle Cell Disease ParticipantsAcute Chest Syndrome (ACS)1 Participants
Secondary

Percentage Change From Baseline in Annualized Number of Packed Red Blood Cell (pRBC) Transfusions

Percentage change from baseline in annualized number of pRBC transfusions from 6 months post-drug product infusion through last visit were reported.

Time frame: Baseline, From 6 months post-drug product infusion through Month 24

Population: This outcome measure was evaluated in the Transplant Population (TP).

ArmMeasureValue (MEDIAN)
LentiGlobin BB305 Drug Product for SCDPercentage Change From Baseline in Annualized Number of Packed Red Blood Cell (pRBC) Transfusions-100.0 percentage change in pRBC transfusion
LentiGlobin BB305 Drug Product for TDTPercentage Change From Baseline in Annualized Number of Packed Red Blood Cell (pRBC) Transfusions-100.0 percentage change in pRBC transfusion
Secondary

Percentage Change From Baseline in Annualized Packed Red Blood Cell (pRBC) Transfusion Volume

Percent change from baseline in the average annual transfusion volume from 6 months post-drug product infusion through last visit were reported.

Time frame: Baseline, From 6 months post-drug product infusion through Month 24

Population: This outcome measure was evaluated in the Transplant Population (TP).

ArmMeasureValue (MEDIAN)
LentiGlobin BB305 Drug Product for SCDPercentage Change From Baseline in Annualized Packed Red Blood Cell (pRBC) Transfusion Volume-100.0 percent change in Annualized pRBC volume
LentiGlobin BB305 Drug Product for TDTPercentage Change From Baseline in Annualized Packed Red Blood Cell (pRBC) Transfusion Volume-100.0 percent change in Annualized pRBC volume
Secondary

Percentage of Treated Participants With Transfusion-Dependent β-Thalassemia (TDT) Who Achieved Transfusion Independence (TI)

TI was defined as a weighted average hemoglobin (Hb) \> or =9 grams per deciliter (g/dL) without any pRBC transfusions for a continuous period of \> or =12 months at any time during the study after drug product infusion, where calculation of time period of TI starts when participants achieve a Hb \> or =9 g/dL with no transfusions in the preceding 60 days.

Time frame: From time of drug product infusion through Month 24

Population: This outcome measure was evaluated only in Transplant Population (TP) with TDT.

ArmMeasureValue (NUMBER)
LentiGlobin BB305 Drug Product for SCDPercentage of Treated Participants With Transfusion-Dependent β-Thalassemia (TDT) Who Achieved Transfusion Independence (TI)75 Percentage of participants
Secondary

Therapeutic Globin Expression Measured by Hb Containing β^A -T87Q Globin (HbA^T87Q) in Peripheral Blood

Therapeutic globin expression was measured by HbA\^T87Q in peripheral blood and the ratio of alpha(α)- globin to all beta (β)-like-globins. The relative amount of each globin produced by a participant (including βA\^A-T87Q globin) was determined in peripheral blood throughout the study.

Time frame: From time of drug product infusion through Month 24

Population: This outcome measure was evaluated in the Transplant Population (TP).

ArmMeasureValue (MEAN)Dispersion
LentiGlobin BB305 Drug Product for SCDTherapeutic Globin Expression Measured by Hb Containing β^A -T87Q Globin (HbA^T87Q) in Peripheral Blood2.947 grams per deciliter (g/dL)Standard Deviation 2.4415
LentiGlobin BB305 Drug Product for TDTTherapeutic Globin Expression Measured by Hb Containing β^A -T87Q Globin (HbA^T87Q) in Peripheral Blood8.287 grams per deciliter (g/dL)Standard Deviation 1.5758
Secondary

Time From LentiGlobin BB305 Drug Product Infusion to Achieving Transfusion Independence (TI) in Participants With Transfusion-Dependent β-Thalassemia (TDT)

TI was defined as a weighted average Hb \> or =9 grams per deciliter (g/dL) without any pRBC transfusions for a continuous period of \> or =12 months at any time during the study after drug product infusion, where calculation of time period of TI starts when participants achieve a Hb \> or =9 g/dL with no transfusions in the preceding 60 days. To meet the initial TI criteria, the weighted Hb must be \> or =9 g/dL at the end of the 12-month period, to remain in the TI state beyond the 12-month period, the treated participant needs to maintain a weighted Hb of \> or =9 g/dL from that point forward, without receiving a pRBC transfusion. This outcome measure reports the time from infusion to achievement of TI.

Time frame: From time of drug product infusion through Month 24

Population: This outcome measure was evaluated only in Transplant Population (TP) with TDT. The number of participants analyzed signifies participants who were evaluable for this specific outcome measure.

ArmMeasureValue (MEDIAN)
LentiGlobin BB305 Drug Product for SCDTime From LentiGlobin BB305 Drug Product Infusion to Achieving Transfusion Independence (TI) in Participants With Transfusion-Dependent β-Thalassemia (TDT)14.9 Month
Secondary

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)

TI was defined as a weighted average Hb \> or =9 grams per deciliter (g/dL) without any pRBC transfusions for a continuous period of \> or =12 months at any time during the study after drug product infusion, where calculation of time period of TI starts when participants achieve a Hb \> or =9 g/dL with no transfusions in the preceding 60 days. To meet the initial TI criteria, the weighted Hb must be \> or =9 g/dL at the end of the 12-month period, to remain in the TI state beyond the 12-month period, the treated participant needs to maintain a weighted Hb of \> or =9 g/dL from that point forward, without receiving a pRBC transfusion. This endpoint reports the time from infusion to the last pRBC transfusion prior to achieving TI.

Time frame: From time of drug product infusion through Month 24

Population: This outcome measure was evaluated only in Transplant Population (TP) with TDT. The number of participants analyzed signifies participants who were evaluable for this specific outcome measure.

ArmMeasureValue (MEDIAN)
LentiGlobin BB305 Drug Product for SCDTime 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)11 Days
Secondary

Vector Copy Number (VCN) in Peripheral Blood

LentiGlobin BB305 lentiviral vector (LVV) transduction efficiency was measured by VCN. The presence of vector sequences in the genomic DNA of cells is detected using quantitative polymerase chain reaction (qPCR), and results were expressed as VCN.

Time frame: From time of drug product infusion through Month 24

Population: This outcome measure was evaluated in the Transplant Population (TP).

ArmMeasureValue (MEAN)Dispersion
LentiGlobin BB305 Drug Product for SCDVector Copy Number (VCN) in Peripheral Blood0.898 copies per diploid genome (c/dg)Standard Deviation 1.1655
LentiGlobin BB305 Drug Product for TDTVector Copy Number (VCN) in Peripheral Blood1.796 copies per diploid genome (c/dg)Standard Deviation 1.3665
Secondary

Weighted Average Hemoglobin (Hb) During Period of Transfusion Independence (TI) in Participants With Transfusion-Dependent β-Thalassemia (TDT)

TI was defined as a weighted average hemoglobin (Hb) \> or =9 grams per deciliter (g/dL) without any pRBC transfusions for a continuous period of \> or =12 months at any time during the study after drug product infusion, where calculation of time period of TI starts when participants achieve a Hb \> or =9 g/dL with no transfusions in the preceding 60 days.

Time frame: From time of drug product infusion through Month 24

Population: This outcome measure was evaluated only in Transplant Population (TP) with TDT. The number of participants analyzed signifies participants who were evaluable for this specific outcome measure.

ArmMeasureValue (MEDIAN)
LentiGlobin BB305 Drug Product for SCDWeighted Average Hemoglobin (Hb) During Period of Transfusion Independence (TI) in Participants With Transfusion-Dependent β-Thalassemia (TDT)11.3 grams per deciliter (g/dL)
Secondary

Weighted Average Nadir Hemoglobin (Hb) in Participants With Transfusion-Dependent β-Thalassemia (TDT)

Weighted average Hb nadir was defined as an average area under the curve where the Hb closest but within 3 days prior to a transfusion was used as the Hb nadir. Hb values on the day of the transfusion were considered for nadir calculations.

Time frame: From 6 months post-drug product infusion through Month 24

Population: This outcome measure was evaluated only in Transplant Population (TP) with TDT.

ArmMeasureValue (MEDIAN)
LentiGlobin BB305 Drug Product for SCDWeighted Average Nadir Hemoglobin (Hb) in Participants With Transfusion-Dependent β-Thalassemia (TDT)11 grams per deciliter (g/dL)

Source: ClinicalTrials.gov · Data processed: Mar 7, 2026