A Phase 1/2 Study to Evaluate the Safety and Efficacy of a Single Dose of Autologous Clustered Regularly Interspaced Short Palindromic Repeats Gene-edited CD34+ Human Hematopoietic Stem and Progenitor Cells (EDIT-301) in Subjects With Severe Sickle Cell Disease

About the study

The purpose of this study is to evaluate the efficacy, safety and tolerability of treatment with EDIT-301 in adult subjects with severe sickle cell disease (SCD).

Study point of contact

Editas Medicine's Clinical Trial Team
[email protected]


18 Years - 50 Years


Phase 1/Phase 2

Study type






participation requirements

Diagnosis of severe sickle cell disease as defined by:

Documented severe SCD genotype (βS/βS, βS/β0, or βS/β+)
History of at least two severe vaso-occlusive crisis events per year requiring medical attention despite hydroxyurea or other supportive care measures in the two year-period prior to provision of informed consent

Karnofsky Performance Status ≥ 80


participation restrictions

Available 10/10 HLA-matched related donor
Prior HSCT or contraindications to autologous HSCT
Any contraindications to the use of plerixafor during the mobilization of hematopoietic stem cells (HSCs) and any contraindications to the use of busulfan and any other medicinal products required during the myeloablative conditioning, including hypersensitivity to the active substances or to any of the excipients
Unable to receive red blood cell (RBC) transfusion for any reason
Unable or unwilling to comply with standard of care changes in background medical treatment in preparation of, during, or following HSCT, including and not limited to discontinuation of hydroxyurea, voxelotor, crizanlizumab, or L-glutamine
Any history of severe cerebral vasculopathy
Inadequate end 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

Last updated 2023-01-10