Inclusion Criteria:

• Have a confirmed diagnosis of GD3 disease
• Have at least 2 impaired domains in the Modified Severity Scoring Tool (mSST) at Screening
• Be aged 4-30 years old at the time of informed consent
• Have the following symptoms of GD3 identified at Screening: GD-related anemia, thrombocytopenia, splenomegaly
• Female participants of childbearing potential who are sexually active and willing to follow contraceptive guidance
• Male participants with a female partner of childbearing potential who are willing to follow contraceptive guidance

Exclusion Criteria:

• Any condition at Screening or Baseline that, in the opinion of the Principal Investigator, could interfere with study assessments
• History of medical conditions other than GD3 that, in the opinion of the Principal Investigator, could confound scientific rigor or interpretation of results
• Body weight <10 kg at Screening
• Presence of a neurologic disease other than GD3
• Transfusion dependence
• Prior splenectomy
• The presence of severe renal impairment at Screening
• Prior use of an investigational drug within 3 months before Screening
• Prior participation in a clinical study involving gene therapy or stem cell transplantation
• Current treatment, or treatment in the last 12 months before Screening, with enzyme replacement therapy (ERT) and/or substrate reduction therapy (SRT)
• A positive serum pregnancy test (for women of childbearing potential)
• Electrocardiogram (ECG) with an average Fridericia-corrected QT interval (QTcF) of >450 msec for males and >470 msec for females at Screening
• Known allergies to azasugars or any study drug excipient