The safety and efficacy of ELELYSO were assessed in 31 patients (26 adult and 5 pediatric patients) with Type 1 Gaucher disease who were switched from imiglucerase to ELELYSO (Trial 3). Trial 3 was a 9-month, multi-center, open-label, single arm study in patients who had been receiving intravenous treatment with imiglucerase at dosages ranging from 9.5 units/kg to 60 units/kg every other week for a minimum of 2 years. Patients were required to be clinically stable and have a stable biweekly dosage of imiglucerase for at least 6 months prior to enrollment. Imiglucerase therapy was stopped, and treatment with ELELYSO was administered every other week at the same number of units as each patient's previous imiglucerase dose (9.5 units/kg to 60 units/kg given intravenously every other week). If needed, adjustment of dosage was allowed during the study in order to maintain stability of clinical parameters (i.e., spleen volume, liver volume, platelet count, and hemoglobin).
- Eighteen of the 26 adult patients who completed the 9-month clinical trial continued treatment with ELELYSO (9.5 units/kg to 60 units/kg given intravenously every other week) in an open-label extension trial for additional 27 months (total duration of ELELYSO treatment was 36 months).
- Five of the pediatric patients who completed the 9-month trial continued open-label treatment with ELELYSO (9.5 units/kg to 60 units/kg given intravenously every other week) for additional 24 months (total duration of ELELYSO treatment was 33 months).
Baseline Demographics
In Trial 3, patients were 6 to 66 years of age (mean age 42 years, including pediatric patients), 55% were male, 97% were White, and 16% and 84% were Hispanic/Latino and non Hispanic/Latino, respectively.
Efficacy Results
In Trial 3, at baseline, spleen volume was 5.2 (4.5) MN, liver volume was 1.0 (0.3) MN, platelet count was 161,137 (73,387)/mm3, and hemoglobin was 13.5 (1.4) g/dL. Mean (SD) organ volumes and hematologic values remained stable through 9 months of ELELYSO treatment. After 9 months of ELELYSO treatment, spleen volume was 4.8 (4.6) MN, liver volume was 1.0 (0.2) MN, platelet count was 161,167 (80,820)/mm3, and hemoglobin was 13.4 (1.5) g/dL. The ELELYSO dosage remained unchanged in 30 of 31 patients. One patient required a dose increase at Week 24 (from 9.5 units/kg to 19 units/kg) for a platelet count of 92,000/mm3 at Week 22, which subsequently increased to 170,000/mm3 at Month 9.
During the 36‑month period, 18 ELELYSO-treated adult patients maintained stability in clinical parameters (spleen volume, liver volume, platelet count and hemoglobin); however only 10 of 18 adult patients completed 27 months of ELELYSO treatment in the extension trial and only 7 patients had their spleen and liver volumes assessed at 36 months.
During the 33-month period, the 5 ELELYSO-treated pediatric patients demonstrated stability in these clinical parameters.