Study of the Effect of Velaglucerase Alfa (VPRIV®) on Bone-related Pathology in Treatment-naïve Participants With Type 1 Gaucher Disease

An Open-label, Multicenter, Single-arm, Phase 4 Study of the Effect of Treatment With Velaglucerase Alfa on Bone-related Pathology in Treatment-naïve Patients With Type 1 Gaucher Disease

The primary purpose of this study is to evaluate the effect of VPRIV therapy (60 units per kilogram [U/kg] every other week [EOW]) in treatment-naive participants with type 1 Gaucher disease on change from baseline in lumbar spine (LS) bone mineral density (BMD) Z-score as measured by dual energy x-ray absorptiometry (DXA) after 24 months of treatment.

Inclusion Criteria:

• The participant has a documented diagnosis of type 1 Gaucher disease, as documented by deficient GCB activity in leukocytes (whole blood only) or cultured skin fibroblasts. Diagnosis by only dry blood spot test is insufficient. Diagnosis may be based on results obtained prior to screening if documented in the participant's medical history.
• Participants must have a LS BMD Z-score less than (<) -1 or BMD T-score of < -1 as measured by DXA during the screening phase.
• Participant is treatment-naive, that is (ie,) has not received ERT or SRT in the 12 months prior to enrollment.
• The participant is greater than or equal to (>=) 18 and less than or equal to (<=) 70 years of age.
• Female participants of childbearing potential must agree to use a medically acceptable method of contraception at all times during the study.
• The participant, or participant's legally authorized representative(s), if applicable, understands the nature, scope, and possible consequences of the study and has provided written informed consent that has been approved by the Institutional Review Board/Independent Ethics Committee (IRB/IEC).
• The participant must be sufficiently cooperative to participate in this clinical study as judged by the investigator.

Exclusion criteria

• Neurological symptoms indicating that the participant may have type 3 Gaucher disease.
• A significant comorbidity, which, as determined by the investigator, might affect study data or confound the study results (eg, malignancies, primary biliary cirrhosis, autoimmune liver disease, etc).
• Any osteoporosis-specific treatment (eg, bisphosphonates) or treatment with erythropoietin (or erythropoietin-like substances) during the past year.
• Structural, joint-associated bone damage of such extent and severity that the investigator deems it could impact participation in the study and assessment of relevant study endpoints (example, pain).
• The participant is pregnant or lactating.
• The participant has had a splenectomy. (This criterion is not meant to exclude participants who have accessory spleens.)
• The participant is enrolled in another clinical study that involves clinical investigations or use of any investigational product (drug or device) within 30 days prior to study enrollment or at any time during the study.
• Severe vitamin D deficiency to the level that would be expected to result in osteomalacia (vitamin D < 10 nanograms per milliliter [ng/mL] [25 nanomoles per liter {nmol/L}]). If there is mild vitamin D insufficiency at screening (vitamin D greater than [>] 10 and < 30 ng/mL) treat with 4000 IU vitamin D per day for 1 month and rescreen.
• The participant has previously interrupted ERT for safety reasons.
• The participant has had hypersensitivity to the active substance or to any of the excipients.