A retrospective and prospective observational study of MRI changes in bone in patients with type 1 Gaucher disease treated with velaglucerase alfa: the EIROS study.

Abstract

Abstract Background Gaucher disease type 1 (GD1) is a rare autosomal recessive disorder characterized by hepatosplenomegaly, thrombocytopenia, and disabling bone manifestations that require regular MRI monitoring to assess disease progression and treatment responses. Velaglucerase alfa therapy results in long-term improvements in hematologic and visceral manifestations, but more real-world data on its impact on bone manifestations are needed. The EIROS study aimed to address this knowledge gap by using MRI data collected in daily practice in France to assess the impact of velaglucerase alfa on GD1 bone disease. Methods Patients with GD1 and bone MRI data from around the time of velaglucerase alfa initiation were eligible for inclusion. All MRIs collected retrospectively from treatment initiation and prospectively to the end of follow-up (12 months) were analyzed centrally by a blinded expert radiologist to evaluate bone infiltration using the Bone Marrow Burden (BMB) score and a qualitative method (scored for the spine and femur: stable, improved or worsened). Abdominal MRIs were also centrally analyzed to assess hepatosplenomegaly. Reports from bone MRIs, X-rays, and abdominal ultrasounds made by local radiologists were also collected. Clinical (acute and chronic bone pain) and biological parameters were analyzed from medical records. Results MRI data were available for 20 patients from 9 hospital centers: 6 treatment-naive patients and 14 patients who switched to velaglucerase alfa from another GD treatment. Readable MRIs for BMB scoring were only available for 7 patients for the spine and 1 patient for the femur. Qualitative assessments, performed for 18 patients, revealed stability in spine and femur infiltration in 100.0% and 84.6% of treatment-switched patients (n = 13), respectively, and improvements in 80.0% and 60.0% of treatment-naive patients, respectively; no worsening of bone infiltration was observed. Liver, spleen and hematologic parameters improved in treatment-naive patients and remained stable in treatment-switched patients. Conclusions This study provided real-world evidence suggesting the long-term effectiveness of velaglucerase alfa treatment in GD1, including bone manifestations. The data indicate that if MRI assessment by a radiologist with experience of GD bone manifestations is not possible, a simplified qualitative assessment provides sufficient evidence in clinical practice for monitoring bone disease progression and treatment response.