Vestronidase alfa

Vestronidase alfa is an enzyme replacement therapy for Mucopolysaccharidosis 7 (MPS 7), also known as Sly Syndrome. 

MPS 7 is a genetic metabolic disorder caused by a deficiency of the lysosomal enzyme beta-glucuronidase, which is required for the breakdown of certain complex carbohydrates known as glycosaminoglycans (GAGs). The inability to break down GAGs leads to their accumulation in many tissues, resulting in serious disease.

Patients with MPS 7 may have abnormal coarsened facial features, enlargement of the liver and spleen, airway obstruction, lung disease, cardiovascular complications, joint stiffness, short stature, and skeletal disease. The severe cellular and organ dysfunction of MPS 7 typically leads to death in the teens or early adulthood.

Ultragenyx has licensed rights to vestronidase alfa from Saint Louis University.

Mechanism of Action

Vestronidase alfa is a therapy intended to replace the deficient lysosomal enzyme beta-glucuronidase to help break down the glycosaminoglycans that accumulate in the tissues of patients with MPS 7.

News & Other Information

Press Releases

• Ultragenyx Announces FDA Approval of MEPSEVII™ (vestronidase alfa), the First Therapy for Progressive and Debilitating Rare Genetic Disease Mucopolysaccharidosis VII (link)

• Ultragenyx Announces Positive Topline Data from Phase 3 Study of Recombinant Human Beta-Glucuronidase in Mucopolysaccharidosis Type 7 (link)

• Ultragenyx Announces Initiation of Phase 2 Study of Recombinant Human Beta-Glucuronidase in Patients Under Five Years Old With Mucopolysaccharidosis 7 (link)

• Ultragenyx Announces Completion of Enrollment in Phase 3 Study of Recombinant Human Beta-Glucuronidase in Mucopolysaccharidosis Type 7 (link)

• Ultragenyx Announces Positive 36-Week Data From Phase 1/2 Study of Recombinant Human Beta-Glucuronidase in Mucopolysaccharidosis 7 (link)

Data Presentations/Publications

• A Novel, Randomized, Placebo-Controlled, Blind-Start, Single-Crossover Phase 3 Study to Assess the Efficacy and Safety of UX003 (rhGUS) Enzyme Replacement Therapy in Patients with MPS VII- MPS Symposium (pdf)

• Enzyme Replacement Therapy With Investigational rhGUS (UX003) in an Infant With Non-immune Hydrops Fetalis (NIHF) and Mucopolysaccharidosis Type VII (MPS VII)- WORLD Symposium 2016* (pdf)
• Evidence of Early Bone Response After Initiation of ERT in a 3-Year Old Patient With MPS VII- WORLD Symposium 2016* (pdf)
• Phase 1/2 36-week results - WORLD Symposium 2015 (pdf)