Gaucher disease is a rare lysosomal storage disorder caused by deficient activity of the enzyme acid β-glucosidase, causing glucosylceramide to accumulate within macrophages and leading to hepatosplenomegaly, anemia, thrombocytopenia, and bone disease. In the non-neuronpathic form (type 1), disease manifestations are mostly systemic, whereas in the neuronopathic forms, glucosylceramide also accumulates in the central nervous sysem and leads to acute (type 2) or chronic (type 3) neurodegeneration. The purpose of this Phase 1/2 first-in-human study is to initially evaluate the safety and tolerability of two doses of CAN103, and then barring any safety concerns, to evaluate the efficacy and safety of the two doses administered intravenously every other week in treatment-naive subjects with Gaucher disease type 1 or type 3.

Phase 1: 4 newly treated subjects with Type I Gaucher disease (GD1). Phase 2: 36 newly treated subjects with GD1 or Type III Gaucher disease (GD3)

Inclusion Criteria:

• Subjects have a confirmed clinical, enzymatic, and genetic diagnosis of Gaucher disease (Type 1 or Type 3);

• Phase 1: Subjects with GD1 aged ≥18 years; Phase 2: Subjects with GD1 or GD3 aged ≥12 years;

• Subjects have not received enzyme replacement therapy (ERT) or substrate replacement therapy (SRT) within 3 months before screening;

• Subjects have GD-related anemia and one or more of the following disease manifestations:

  1. Spleen volume ≥2 MN as measured by MRI, or
  2. Liver volume ≥1.5 MN as measured by MRI, or
  3. Platelet count ≥20 × 10^9/L and <100×10^9/L.

Exclusion Criteria:

• Subjects have received or stopped treatment with other investigational drugs or devices within 30 days before screening or less than 5 half-lives, whichever is longer (drugs only);
• Subjects have anemia due to other causes during screening, including nutritional anemia. Subjects whose nutritional anemia recovers with the treatment of iron, folic acid, or Vitamin B12 may be rescreened;
• Subjects have received hepatectomy or splenectomy;
• Subjects have had an allergic reaction to imiglucerase or other ERTs and their components;
• Subjects have received treatment with erythropoietin, whole blood or packed red blood cell transfusions, or chronic systemic corticosteroids within 3 months before screening, or have received a platelet transfusion within 1 month before screening.

Phase 2 is blinded to dose group. Except for the non-blind team, no other participants associated with this study should attempt to learn the treatment group assignment or which study treatment they are receiving. The unblinding of all subjects will take place after database lock.