MGTA-456 in Patients With Inherited Metabolic Disorders Undergoing Hematopoietic Stem Cell Transplantation (HSCT)

This phase 2 study is designed to evaluate the safety and efficacy of MGTA-456 in patients with IMD after receiving myeloablative conditioning and HSCT. MGTA-456 is an expanded CD34+ cell therapy product candidate given to induce rapid and sustained hematopoietic engraftment. In patients with selected IMDs, transplant is expected to replace defective or missing protein and preserve neurodevelopment. Since MGTA-456 offers increased numbers of HSCs over standard umbilical cord blood, it is expected to reduce the risks of prolonged neutropenia and thrombocytopenia and graft failure, and potentially transplant-related mortality (TRM). Patients with Hurler syndrome (also referred to as mucopolysaccharidosis-1H (MPS-1H)), cerebral adrenoleukodystrophy (cALD), metachromatic leukodystrophy (MLD) or globoid cell leukodystrophy (GLD) (also referred to as Krabbe disease) are eligible for this study.

Inclusion criteria

• Age < 2.5 years with Hurler syndrome, age 2-17 years with cerebral adrenoleukodystrophy (cALD), age < 16 years with metachromatic leukodystrophy (MLD) and age ≤ 10 years with globoid cell leukodystrophy (GLD) (also referred to as Krabbe)
• Cord blood grafts require genetic testing and/or demonstration of enzyme activity for patients with Hurler syndrome, MLD or GLD and are tested for very long chain fatty acids (VLCFA) to confirm there is no evidence of VLCFA consistent with ALD
• Adequate organ function
• Availability of eligible donor material

Exclusion criteria

• Availability of a matched-related donor who is not a carrier of the same genetic defect
• Active infection at screening
• Prior myeloablative conditioning
• History of human immunodeficiency virus (HIV) infection