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EDIT-301 for Autologous Hematopoietic Stem Cell Transplant (HSCT) in Participants With Transfusion-Dependent Beta Thalassemia (TDT)

Phase 1
Active, not recruiting
Conditions
Hemoglobinopathies
Transfusion Dependent Beta Thalassemia
Thalassemia Intermedia
Thalassemia Major
Registration Number
NCT05444894
Lead Sponsor
Editas Medicine, Inc.
Brief Summary

The purpose of this study is to evaluate the safety, tolerability, and efficacy of treatment with EDIT-301 in adult participants with Transfusion Dependent beta Thalassemia

Detailed Description

This is a Phase 1/2 single-arm, open-label, multicenter study evaluating the safety, tolerability, and efficacy of a single unit dose of EDIT-301 for autologous hematopoietic stem cell transplant in adult participants with TDT, age 18 to 35 years, inclusive

Recruitment & Eligibility

Status
ACTIVE_NOT_RECRUITING
Sex
All
Target Recruitment
9
Inclusion Criteria

Diagnosis of Transfusion Dependent B-Thalassemia as defined by:

  • Documented homozygous β-thalassemia or compound heterozygous β-thalassemia including β-thalassemia/hemoglobin E (HbE) based on historical data in medical records, and
  • History of at least 100 mL/kg/year or 10 U/year of packed red blood cell (RBC) transfusions in the 2 years prior to signing informed consent
  • Clinically stable and eligible to undergo autologous HSCT
  • Karnofsky Performance Status ≥ 70

Key

Exclusion Criteria
  • Available 10/10 human leukocyte antigen (HLA)-matched related donor
  • Prior HSCT or contraindications to autologous HSCT
  • Participants with associated a history of α-thalassemia and > 1 alpha chain deletion, or alpha multiplications as documented in medical records
  • Participants with a history of other inherited hemoglobinopathy or thalassemic mutation (Hb S, C, D or other) as documented in medical records
  • Prior receipt of gene therapy
  • Inadequate bone marrow function, as defined by white blood cell count of < 3 x 10^9/L or a platelet count < 100 x 10^9/L (without hypersplenism), per investigator judgement
  • Inadequate organ function
  • Advanced liver disease
  • Any prior or current malignancy, or immunodeficiency disorder,
  • Immediate family member with a known or suspected Familial Cancer Syndrome
  • Clinically significant and active bacterial, viral, fungal, or parasitic infection

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Primary Outcome Measures
NameTimeMethod
Proportion of participants achieving engraftment defined as neutrophil engraftment (defined as demonstrating absolute neutrophil count (ANC) ≥ 0.5 x 10^9/L post EDIT-301 infusion for 3 consecutive measurements obtained on different days)EDIT-301 infusion (Day 0) to 42 days post EDIT-301 infusion
Frequency and severity of adverse events (AEs) (incidence of AEs and Grade 3 or higher serious adverse events, using National Cancer Institute Common Terminology Criteria for Adverse Events [NCI CTCAE] v.5.0)Screening through up to 24 months post EDIT-301 infusion
Secondary Outcome Measures
NameTimeMethod
Change in the fetal hemoglobin (HbF) concentration compared to baseline overtimeBaseline through up to 24 months post EDIT-301 infusion
Proportion of participants with hemoglobin concentration ≥ 9 g/dLEDIT-301 infusion (Day 0) through 3, 6, 12 months up to 24 months post EDIT-301 infusion
Proportion of alleles per participant with intended genetic modification present in bone marrow cells over timeEDIT-301 infusion (Day 0) through up to 24 months post EDIT-301 infusion
Incidence of all-cause mortalityScreening through up to 24 months post EDIT-301 infusion
Proportion of alleles per participant with intended genetic modification present in peripheral blood over timeEDIT-301 infusion (Day 0) through up to 24 months post EDIT-301 infusion
Change in the total hemoglobin concentration compared to baseline overtimeBaseline through up to 24 months post EDIT-301 infusion
Change in parameters of iron overload compared to baseline over timeBaseline through up to 24 months post EDIT-301 infusion
Kinetics of HSPC engraftmentEDIT-301 infusion (Day 0) to first day of 3 consecutive measurements of platelets ≥ 50 x 10^9/L for at least 1 week following the last platelet transfusion and 10 days following thrombopoietin mimetics use up to 24 months post EDIT-301 infusion.

Time to platelet engraftment

Proportion of participants achieving the sustained transfusion reduction (TR) for at least 6 months and at least 12 months from 3 months post-EDIT-301 infusion3 months post EDIT-301 infusion through up to 24 months post EDIT-301 infusion
Proportion of participants achieving the sustained transfusion independence (TI) for at least 6 months and, at least 12 months from 3 months post EDIT-301 infusion3 months through up to 24 months post EDIT-301 infusion
Proportion of participants receiving iron chelation therapy over timeEDIT-301 infusion (Day 0) through up to 24 months post EDIT-301 infusion
Incidence of transplant related mortalityEDIT-301 infusion (Day 0) through Day 100 post EDIT-301 infusion and from EDIT-301 infusion (Day 0) through 12 months post EDIT-301 infusion

Trial Locations

Locations (8)

University of California San Francisco

🇺🇸

Oakland, California, United States

University of Minnesota

🇺🇸

Minneapolis, Minnesota, United States

Columbia University Medical Center - Department of Pediatrics

🇺🇸

New York, New York, United States

Columbia University Medical Center

🇺🇸

New York, New York, United States

Cleveland Clinic

🇺🇸

Cleveland, Ohio, United States

Children's Hospital of Philadelphia

🇺🇸

Philadelphia, Pennsylvania, United States

Tristar Medical Group Children's Specialists/Sarah Cannon Center for Blood Cancers

🇺🇸

Nashville, Tennessee, United States

Princess Margaret Cancer Centre-University Health Network

🇨🇦

Toronto, Ontario, Canada

University of California San Francisco
🇺🇸Oakland, California, United States

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